Effect of a commercial anionic dietary supplement on urinary pH and concentrations of electrolytes and pH in blood of horses

Aims: To compare urine urinary pH, blood pH and concentration of electrolytes in blood of healthy horses fed an anionic salt supplement to achieve diets with a dietary cation-anion difference (DCAD) of -40 or 0 mEq/kg DM, with horses a fed a diet with a DCAD of 85 mEq/kg DM.Methods: Eight healthy horses received each of three diets in a randomised crossover design. Diets consisted of grass hay and concentrate feed, with a varying amount of an anionic supplement to achieve a DCAD of 85 (control), 0 or -40 mEq/kg DM. They were fed for 14 days each with a washout period of 7 days between. Urine pH was measured daily and blood samples were collected on Days 0, 7 and 14 of each study period for the measurement of pH and concentration of electrolytes.Results: Four horses voluntarily consumed the anionic supplement with their feed, but four horses required oral supplement administration via dose syringe. During the study period mean urine pH was lower in horses fed diets with a DCAD of 0 (6.91; SD 0.04) and -40 (6.83; SD 0.04) mEq/kg DM compared to the control diet (7.30; SD 0.04). Compared with horses fed the control diet, mean urine pH was lower in horses fed the 0 and -40 mEq/kg DM diets on Days 1-12 and 14 (p < 0.05) of the study period. On Day 13 it was only lower in horses fed the -40 mEq/kg DM diet (p < 0.01). Urine pH was similar for horses fed the 0 and -40 mEq/kg DM diets (p = 0.151). The DCAD of the diet had no effect on blood pH, ionised Ca or anion gap. Mean concentrations of bicarbonate in blood were affected by diet (p = 0.049); they were lower when horses were fed the 0 mEq/kg diet relative to the control diet on Day 14.Conclusions and clinical relevance: The anionic supplement reduced urine pH in horses fed diets with a DCAD of 0 or -40 mEq/kg DM compared with 85 mEq/kg DM. However as urinary pH did not fall below pH 6.5, the pH below which calcium carbonate uroliths do not form, this reduction in urine pH is unlikely to be clinically significant. The supplement was variably palatable and showed minimal promise as an effective urinary acidifier at the doses administered in this study.

Using cognitive pre-testing methods in the development of a new evidenced-based pressure ulcer risk assessment instrument

Background

Variation in development methods of Pressure Ulcer Risk Assessment Instruments has led to inconsistent inclusion of risk factors and concerns about content validity. A new evidenced-based Risk Assessment Instrument, the Pressure Ulcer Risk Primary Or Secondary Evaluation Tool - PURPOSE-T was developed as part of a National Institute for Health Research (NIHR) funded Pressure Ulcer Research Programme (PURPOSE: RP-PG-0407-10056). This paper reports the pre-test phase to assess and improve PURPOSE-T acceptability, usability and confirm content validity.

Methods

A descriptive study incorporating cognitive pre-testing methods and integration of service user views was undertaken over 3 cycles comprising PURPOSE-T training, a focus group and one-to-one think-aloud interviews. Clinical nurses from 2 acute and 2 community NHS Trusts, were grouped according to job role. Focus group participants used 3 vignettes to complete PURPOSE-T assessments and then participated in the focus group. Think-aloud participants were interviewed during their completion of PURPOSE-T.

After each pre-test cycle analysis was undertaken and adjustment/improvements made to PURPOSE-T in an iterative process. This incorporated the use of descriptive statistics for data completeness and decision rule compliance and directed content analysis for interview and focus group data. Data were collected April 2012-June 2012.

Results

Thirty-four nurses participated in 3 pre-test cycles. Data from 3 focus groups, 12 think-aloud interviews incorporating 101 PURPOSE-T assessments led to changes to improve instrument content and design, flow and format, decision support and item-specific wording. Acceptability and usability were demonstrated by improved data completion and appropriate risk pathway allocation. The pre-test also confirmed content validity with clinical nurses.

Conclusions

The pre-test was an important step in the development of the preliminary PURPOSE-T and the methods used may have wider instrument development application. PURPOSE-T proposes a new approach to pressure ulcer risk assessment, incorporating a screening stage, the inclusion of skin status to distinguish between those who require primary prevention and those who require secondary prevention/treatment and the use of colour to support pathway allocation and decision making. Further clinical evaluation is planned to assess the reliability and validity of PURPOSE-T and it’s impact on care processes and patient outcomes.

Feasibility of low radiation dose retrospectively-gated cardiac CT for functional analysis in adult congenital heart disease

Background:

The use of cardiac computed tomography (CT) in the evaluation of adult congenital heart disease patients is limited due to concerns of high radiation doses. The purpose of this study was to prospectively assess whether low radiation dose cardiac CT is feasible to evaluate ventricular systolic function in adults with congenital heart disease.

Methods:

The study group included 30 consecutive patients with significant congenital heart disease who underwent a total of 35 ECG-gated cardiac CT scans utilizing a 320-detector row CT scanner. Each study included a non-contrast scan and subsequent contrast-enhanced retrospectively-gated acquisition. Effective radiation dose was estimated by multiplying the dose length product by a k-factor of 0.014 mSv/mGy cm.

Results:

The mean age of the patients was 34.4 ± 8.9 years, 60% were men, and mean body mass index was 24.2 ± 4.3 kg/m². A majority of patients (n = 28, 93.3%) had contraindications to cardiac MRI. A tube potential of 80 kV was used in 27 (77.1%) of the contrast-enhanced scans. The mean signal-to-noise and contrast-to-noise ratios were 11.5 ± 3.9 and 10.3 ± 3.7, respectively. The median radiation dose for non-contrast and contrast-enhanced images were 0.1 mSv (0.07–0.2 mSv) and 0.94 mSv (0.5–2.1 mSv), respectively. All 35 CT scans were successfully analyzed for ventricular systolic function.

Conclusions:

A low radiation contrast-enhanced, retrospectively-gated cardiac CT with a median radiation dose of less than 1 mSv was successful in evaluating ventricular systolic function in 30 consecutive adult congenital heart disease patients who underwent a total of 35 scans.

Porcine epidemic diarrhea virus: An overview of current virological and serological diagnostic methods

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Molecular assays such as rRT-PCR are the method of choice for PEDV diagnosis.

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Multiplex rRT-PCR allow simultaneous testing for PEDV, TGEV and PDCoV.

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Serological assays provide valuable information on previous exposure to PEDV and population immunity.

Porcine epidemic diarrhea virus (PEDV) is the causative agent of an acute, highly contagious, and severe enteric disease that leads to high mortality rates in suckling piglets. Therefore, accurate diagnosis of PEDV infection is critical for the implementation of control measures for the virus. Many diagnostic tests have been recently developed and are currently available for the detection of PEDV, its proteins or nucleic acid, including virus isolation, immunofluorescence (IF) or immunohistochemistry (IHC), polymerase chain reaction (PCR) and isothermal amplification assays. Additionally, several serological assays have been developed and are currently used for the detection of antibodies against PEDV. Molecular assays such as real-time reverse transcriptase-PCR (rRT-PCR) became the methods of choice for the diagnosis of PEDV infection, providing sensitive, specific and rapid detection of the virus RNA in clinical samples. Whereas serological assays have been widely used to monitor prior exposure to the virus and to evaluate the efficacy of novel vaccine candidates or vaccination strategies. Here we discuss the properties of current PEDV diagnostic assays and prospects for improving diagnostic strategies in the future.

Spinal Cord Hamartomatous Myelodysplasia in 2 Horses With Clinical Neurologic Deficits

Two horses euthanized for neurologic deficits were diagnosed with hamartomatous myelodysplasia of the spinal cord. One was a 5-week-old Holsteiner colt exhibiting spasms of muscle rigidity in the extensor muscles of the limbs and epaxial muscles, and the other was a 3-year-old Thoroughbred colt exhibiting progressive ataxia and hypermetria in the pelvic limbs. Each had focal disorganization of the white and gray matter of the spinal cord forming a mass interspersed with neurons, glial cells, and disoriented axon bundles. In the Holsteiner colt, the mass was at the level of C5 and included islands of meningeal tissue contiguous with the leptomeninges. The mass occluded the central canal forming hydromyelia cranial to the occlusion. In the Thoroughbred colt, the mass was at the level of L1 on the dorsal periphery of the spinal cord and did not involve the central canal.

VenUS III: a randomised controlled trial of therapeutic ultrasound in the management of venous leg ulcers

OBJECTIVES

To compare the clinical effectiveness and cost-effectiveness of low-dose ultrasound delivered in conjunction with standard care against standard care alone in the treatment of hard-to-heal venous ulcers.

DESIGN

A multicentre, pragmatic, two-armed randomised controlled trial with an economic evaluation.

SETTING

Community nurse services; community leg ulcer clinics; hospital outpatient leg ulcer clinics, among both urban and rural settings in England, Scotland, Northern Ireland and Ireland.

PARTICIPANTS

Patients with a venous leg ulcer of > 6 months' duration or > 5 cm2 and an ankle-brachial pressure index of ≥ 0.8. In total, 337 patients were recruited to the study.

INTERVENTIONS

Participants in the intervention group received low-dose ultrasound (0.5 W/cm2) delivered at 1 MHz, pulsed pattern of 1 : 4, applied to periulcer skin (via a water-based contact gel) weekly for up to 12 weeks alongside standard care. Standard care consisted of low-adherent dressings and compression therapy, renewed as recommended by the patient's nurse and modified if required to reflect changes in ulcer and skin condition. The output of the ultrasound machines was checked every 3 months to confirm intervention fidelity.

MAIN OUTCOME MEASURES

The primary end point was time to healing of the largest eligible ulcer (reference ulcer). Secondary outcomes were time to healing of all ulcers, proportion of patients healed, percentage and absolute change in ulcer size, proportion of time patients were ulcer free, cost of treatments, health-related quality of life (HRQoL), adverse events, withdrawal and loss to follow-up.

RESULTS

There was a small, and statistically not significant, difference in the median time to complete ulcer healing of all ulcers in favour of standard care [median 328 days, 95% confidence interval (CI) 235 days, inestimable] compared with ultrasound (median 365 days, 95% CI 224 days, inestimable). There was no difference between groups in the proportion of patients with ulcers healed at 12 months (72/168 in ultrasound vs 78/169 standard care), nor in the change in ulcer size at 4 weeks. There was no evidence of a difference in recurrence of healed ulcers. There was no difference in HRQoL [measured using the Short Form questionnaire-12 items (SF-12)] between the two groups. There were more adverse events with ultrasound than with standard care. Ultrasound therapy as an adjuvant to standard care was found not to be a cost-effective treatment when compared with standard care. The mean cost of ultrasound was £197.88 (bias-corrected 95% CI -£35.19 to £420.32) higher than standard care per participant per year. There was a significant relationship between ulcer healing and area and duration at baseline. In addition, those centres with high recruitment rates had the highest healing rates.

CONCLUSIONS

Low-dose ultrasound, delivered weekly during dressing changes, added to the package of current best practice (dressings, compression therapy) did not increase ulcer healing rates, affect quality of life (QoL) or reduce recurrence. It was associated with higher costs and more adverse events. There is no evidence that adding low-dose ultrasound to standard care for 'hard-to-heal' ulcers aids healing, improves QoL or reduces recurrence. It increases costs and adverse events. The relationship between ulcer healing rates and patient recruitment is worthy of further study.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN21175670.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 15, No. 13. See the HTA programme website for further project information.

Economic evaluation of a randomized controlled trial of ultrasound therapy for hard-to-heal venous leg ulcers

Background

A pragmatic, multicentre randomized controlled trial (VenUS III) was conducted to determine whether low-dose ultrasound therapy increased the healing rate of hard-to-heal leg ulcers. This study was a cost-effectiveness analysis of the trial data.

Methods

Cost-effectiveness and cost–utility analyses were conducted alongside the VenUS III trial, in which patients were randomly allocated to either ultrasound treatment administered weekly for 12 weeks along with standard care, or standard care alone. The time horizon was 12 months and based on the UK National Health Service (NHS) perspective.

Results

The base-case analysis showed that ultrasound therapy added to standard care was likely to be more costly and provide no extra benefit over standard care alone. Individuals who received ultrasound treatment plus standard care took a mean of 14·7 (95 per cent confidence interval − 32·7 to 56·8) days longer to heal, had 0·009 (−0·042 to 0·024) fewer quality-adjusted life years and had higher treatment costs by £197·88 (−35·19 to 420·32). Based on these point estimates, ultrasound therapy plus standard care for leg ulcers was dominated by standard care alone. The analysis of uncertainty showed that this treatment strategy is unlikely to be cost-effective.

Conclusion

Ultrasound treatment was not cost-effective for hard-to-heal leg ulcers and should not be recommended for adoption in the NHS. Registration number: ISRCTN21175670 (http://www.controlled-trials.com) and N0484162339 (National Research Register).

Impact of multilayered compression bandages on sub-bandage interface pressure: a model

Background

Multi-component medical compression bandages are widely used to treat venous leg ulcers. The sub-bandage interface pressures induced by individual components of the multi-component compression bandage systems are not always simply additive. Current models to explain compression bandage performance do not take account of the increase in leg circumference when each bandage is applied, and this may account for the difference between predicted and actual pressures.

Objective

To calculate the interface pressure when a multi-component compression bandage system is applied to a leg.

Method

Use thick wall cylinder theory to estimate the sub-bandage pressure over the leg when a multi-component compression bandage is applied to a leg.

Results

A mathematical model was developed based on thick cylinder theory to include bandage thickness in the calculation of the interface pressure in multi-component compression systems. In multi-component compression systems, the interface pressure corresponds to the sum of the pressures applied by individual bandage layers. However, the change in the limb diameter caused by additional bandage layers should be considered in the calculation. Adding the interface pressure produced by single components without considering the bandage thickness will result in an overestimate of the overall interface pressure produced by the multi-component compression systems. At the ankle (circumference 25 cm) this error can be 19.2% or even more in the case of four components bandaging systems.

Conclusion

Bandage thickness should be considered when calculating the pressure applied using multi-component compression systems.

Abstract P6-15-12: Preclinical Evaluation of a STAT3 Inhibitor in Breast Cancer

Breast cancer often arises from inappropriate activation of transcription factors involved in normal mammary development, such as the signal transducers and activators of transcription (STAT) family of transcription factors. STAT3, which plays an important role in mammary remodeling, is activated (as assessed by tyrosine phosphorylation) in approximately 70% of primary breast cancers, with many of these tumors being highgrade. Furthermore, inhibition of STAT3 leads to a loss of tumorigenicity of breast cancer cells. Therefore, targeting STAT3 in breast cancer would be a potentially beneficial form of therapy.

To identify small molecule STAT3 inhibitors, we developed a high throughput cell-based assay to identify compounds that inhibit STAT3- dependent transcriptional activity. We screened approximately 200,000 compounds, and specificity for STAT3 was ensured by eliminating molecules that inhibited either STAT1- or NF-kappaB-dependent transcriptional activity. From this screen, we identified 4-[4-(phenylmethyl) piperidin-1-yl] thieno[2,3-d]pyrimidine (PMPTP) (Probe ID ML116) as a potent inhibitor of STAT3 transcriptional activity, which has no effect on STAT1 or NF-kappaB-dependent transcriptional activity. Treatment with PMPTP of MDA-MB-468 breast cancer cells, which contain constitutively activated STAT3, leads to inhibition of expression of STAT3 target genes including bcl-x and mcl1. Furthermore, PMPTP is a potent inhibitor of viability of MDA-MB-468 breast cancer cells. By contrast, SK-BR-3 cells, which do not contain constitutively active STAT3, were only minimally affected. This suggests that PMPTP reduces the viability of cells that depend on constitutively active STAT3. PMPTP has no effect on STAT3 tyrosine or serine phosphorylation or STAT3 nuclear translocation, suggesting that PMPTP may be inhibiting STAT3 at the level of DNA binding or co-factor recruitment.

Importantly, PMPTP lowers the apoptotic potential of breast cancer cells thereby making them more susceptible to other forms of therapy. Building on this observation, we identified a number of beneficial combinations of PMPTP with cytotoxic drugs currently used in breast cancer therapy as well as novel anti-cancer agents. Additionally, we analyzed a number of structural analogues of PMPTP, and we identified two compounds that had approximately 4-fold increased potency in inhibiting the viability of breast cancer cells containing STAT3 activation.

Taken together, these findings identify PMPTP as a potential new form of therapy for breast cancers containing activated STAT3, which can be enhanced using conventional and non-conventional chemotherapy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-15-12.

Impact of variation in limb shape on sub-bandage interface pressure

BACKGROUND

Sub-bandage interface pressure generated by medical compression bandages (MCB) and hosiery changes in mobile patients as they move due to the change in the limb size. However, the amount of variation in the interface pressure is dependent on the stiffness of the compression material. Researchers have proposed several indices to describe this change in interface pressure, including the static stiffness index (SSI) and the dynamic stiffness index (DSI). These indices can also be used to classify compression products.

OBJECTIVES

To explore the different proposed indices to describe the stiffness of a compression material and compare it to the engineering stress-strain modulus which is used for the same purpose; To estimate theoretically the change in the interface pressure which is caused by the change in the limb shape as a consequence of calf muscle activity and the associated transient variation in limb dimensions.

METHOD

Use Chord modulus to classify compression material; Use thin and thick cylinder wall theory to estimate the variation in the interface pressure due to changes in the limb shape secondary to muscle contraction; Use tensile test devices to obtain the Chord modulus for two different MCB at two different dynamic ranges.

RESULTS

Chord modulus (E) describes the change in tension in a dynamic situation, and this is labelled as stiffness in the bandaging literature; Chord modulus, with the help of a mathematical model that was developed based on thick wall cylinder theory, can be used to predict the change in sub-bandage interface pressure caused by the change in limb shape secondary to calf muscle activity; Chord modulus can be used to classify bandages and describe how they will behave when they are applied to a leg.

CONCLUSION

The dynamic pressure can be predicted using a simple mathematical model using Chord modulus, which can be calculated in vitro using standard tensile testing equipment. In addition, Chord modulus can be used to classify compression bandages and hosiery.

Vascular lesions in pigs experimentally infected with porcine circovirus type 2 serogroup B

Vasculitis is a hallmark lesion of the severe form of systemic porcine circovirus-associated disease (PCVAD). In 2 experimental studies with porcine circovirus type 2 serogroup b (PCV2b), 2 pigs developed fatal PCVAD with acute vasculitis, and 5 related pigs developed chronic lymphohistiocytic and plasmacytic peri- and endarteritis. Five of these pigs (1 with acute vasculitis and 4 with chronic vasculitis) had also been inoculated with bovine viral diarrhea virus type 1 (BVDV1) or BVDV1-like virus. Vascular lesions were similar, independent of whether pigs had been inoculated singly with PCV2b or dually with PCV2b and BVDV1 or BVDV1-like virus. The acute vasculitis was accompanied by marked pulmonary and mesenteric edema and pleural effusion. In situ hybridization demonstrated abundant intracytoplasmic porcine circovirus type 2 (PCV2) nucleic acid in endothelial, smooth muscle-like, and inflammatory cells within and around affected arteries. The pigs with lymphohistiocytic and plasmacytic vasculitis had lesions of systemic PCVAD, including multisystemic lymphoplasmacytic and histiocytic or granulomatous inflammation. PCV2 nucleic acid was detected in renal tubule epithelial cells, mononuclear inflammatory cells, and rare endothelial cells in noninflamed vessels in multiple tissues of these animals. The 2 pigs with acute vasculitis had no PCV2-specific antibodies (or a low titer of), whereas the pigs with lymphohistiocytic and plasmacytic vasculitis developed high antibody titers against this virus. These observations suggest that (1) acute vasculitis observed in the current studies is directly caused by PCV2b, (2) chronic vasculitis may in part be mediated by the subsequent immune response, and (3) host factors and viral strain may both contribute to vasculitis in animals infected with PCV2b.

VenUS II: a randomised controlled trial of larval therapy in the management of leg ulcers

OBJECTIVES

To compare the clinical effectiveness and cost-effectiveness of larval therapy with a standard debridement technique (hydrogel).

DESIGN

A pragmatic, three-arm, randomised controlled trial with an economic evaluation.

SETTING

Community nursing services, community leg ulcer clinics and hospital outpatient leg ulcer clinics. A range of urban and rural settings.

PARTICIPANTS

Patients with venous or mixed venous/arterial ulcers (minimum ankle brachial pressure index of 0.6) where a minimum of 25% of ulcer area was covered by slough and/or necrotic material.

INTERVENTIONS

Loose larval therapy and bagged larval therapy compared with hydrogel.

MAIN OUTCOME MEASURES

The primary end point was complete healing of the largest eligible ulcer. The primary outcome was time to complete healing of the reference ulcer. Secondary outcomes were: time to debridement, cost of treatments, health-related quality of life (including ulcer-related pain), bacterial load, presence of methicillin-resistant Staphylococcus aureus and staff and patient attitudes to and beliefs about larval therapy.

RESULTS

Between July 2004 and May 2007 the trial recruited 267 people aged 20-94 years at trial entry. There were more female (n = 158) than male (n = 109) participants and most ulcers were classified by the nurse as having an area greater than 5 cm(2). The time to healing for the three treatment arms was compared using the log rank test. The difference in time to healing in the three treatments was not statistically significant at the 5% level. Adjustment was then made for stratification and prespecified prognostic factors (centre, baseline ulcer area, ulcer duration and type of ulcer) using a Cox proportional hazards model. No difference was found in healing rates between the loose and bagged larvae groups. Results for larvae (loose and bagged pooled) compared with hydrogel showed no evidence of a difference in time to healing. When the same analytical steps were used to investigate time to debridement, larvae-treated ulcers debrided significantly more rapidly than hydrogel-treated ulcers; however, the difference in time to debridement between loose and bagged larvae was not significant. The adjusted analysis reported the hazard of debriding at any time for those in loose and bagged larvae groups as approximately twice that of the hydrogel group. No differences in health-related quality of life or bacteriology were observed between trial arms. Larval therapy was associated with significantly more ulcer-related pain than hydrogel. Our base-case economic evaluation showed large decision uncertainty associated with the cost-effectiveness of larval therapy compared with hydrogel, suggesting that larval therapy and hydrogel therapy have similar costs and effects in the treatment of sloughy and/or necrotic leg ulcers.

CONCLUSIONS

Larval therapy significantly reduced the time to debridement of sloughy and/or necrotic, chronic venous and mixed venous/arterial leg ulcers, compared with hydrogel; however, larval therapy did not significantly increase the rate of healing of the ulcers. It was impossible to distinguish between larval therapy and hydrogel in terms of cost-effectiveness. Future research should investigate the association of debridement and healing and the value of debridement as a clinical outcome for patients and clinicians. To inform decision-makers' selection of debriding agents where debridement is the treatment goal, decision analytic modelling of all alternative debridement treatments is required.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN55114812.

Evaluation of the risk of PRRSV transmission via ingestion of muscle from persistently infected pigs

The objectives of this experiment were to determine how long porcine reproductive and respiratory syndrome virus (PRRSV) could be detected in muscle tissues of experimentally infected pigs and to evaluate the transmissibility of PRRSV to pigs via ingestion of quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR)-positive muscle tissues. Serum, lymphoid tissues, and muscle (M. longissimus dorsi) samples were collected from 135 pigs (89 PRRSV-inoculated pigs and 46 negative control). Between 28 and 202 days post-inoculation, 13 of 89 (14.6%) muscle samples were positive by qRT-PCR. Among these 13, PRRSV was isolated from four of the 13 corresponding serum samples and three of 13 lymphoid tissue samples. In addition, infectious virus was detected in lymphoid tissue homogenates of six of 13 pigs by intramuscular bioassay. Swine transmissibility studies were performed by feeding thirteen 3-week-old PRRSV-naive pigs (recipient pigs) qRT-PCR-positive muscle and then monitoring recipients for evidence of PRRSV viremia by qRT-PCR. No transmission of PRRSV to recipient pigs via consumption of muscle samples was observed. These data suggested that qRT-PCR detected non-infectious PRRSV in pig meat and/or PRRSV is not highly transmissible to susceptible pigs via consumption of PRRSV-contaminated meat.

Immune response against porcine reproductive and respiratory syndrome virus during acute and chronic infection

A significant obstacle to the prevention and control of porcine reproductive and respiratory syndrome virus (PRRSV) is the inability of current diagnostic tests to provide information concerning the stage of PRRSV infection. To explore possible prognostic combinations of cell-mediated and humoral immune responses, 3-week-old pigs (n=10) were intramuscularly (IM) inoculated with PRRSV isolate VR-2332 and followed for 193 days post-inoculation (DPI). Negative control pigs (n=10) were IM inoculated with minimum essential medium (MEM). At approximately 2-week intervals, blood samples were collected from all animals and tested for the number of interferon (IFN)-gamma-secreting peripheral blood mononuclear cells (enzyme-linked immunosorbent spot, Elispot), PRRSV viremia (quantitative reverse-transcriptase polymerase chain reaction, qRT-PCR), and serum antibodies using PRRSV protein ELISAs (N, GP5 3', GP5 5', M 5', M 3', GP5-M, and nsp2p) and a commercial PRRSV ELISA (IDEXX Laboratories Inc.). All pigs were viremic by 7 days post-inoculation, with 50% of the pigs resolving viremia by 56 DPI. A PRRSV-specific IFN-gamma response was detected at DPI 28, reached a plateau at 42 DPI, declined slightly, and remained relatively stable from 56 to 193 DPI. On the basis of ROC area under the curve (AUC) analysis, the ELISAs that most reliably differentiated PRRSV-inoculated pigs from negative control pigs were the commercial ELISA (AUC=0.97), the N ELISA (AUC=0.96), and the M 3' ELISA (AUC=0.93). Multivariate analyses were performed to evaluate the relationship between the immune response and the duration and level of viremia. With all antibody assays and Elispot included in the models, the analysis determined that the serum-virus neutralizing antibody response was the best predictor of both level and duration of viremia. It was concluded that humoral antibody responses, particularly the commercial ELISA, N ELISA, and M 3' ELISA were good predictors of prior exposure to PRRSV, but provided little information regarding the ontogeny of the protective immune response. Likewise, cell-mediated immunity based on the number of IFN-gamma-secreting lymphocytes was a poor prognosticator of PRRSV infection status.

A systematic review of topical negative pressure therapy for acute and chronic wounds

BACKGROUND

Topical negative pressure (TNP) therapy is becoming increasingly popular for all kinds of wounds. Its clinical and cost effectiveness is unclear.

METHODS

A search of randomized controlled trials (RCTs) on TNP in adult patients with all kinds of wounds in all settings was undertaken in Medline, Embase, Cinahl (to October 2007) and the Cochrane Library (to issue 4, 2007). Information was also sought from manufacturer of the VAC device. Selection of trials for analysis, quality assessment, data abstraction and data synthesis were conducted by two authors independently. The primary endpoint was any measure of wound healing. Secondary endpoints were infection, pain, quality of life, oedema, microcirculation, bacterial load, adverse events, duration of hospital stay and cost.

RESULTS

The search identified 15 publications on 13 RCTs. These reported on patients with chronic wounds, diabetic wounds, pressure ulcers, skin grafts and acute wounds. In chronic and diabetic wounds, TNP did not allow earlier complete wound healing. It was, however, associated with a 1-10 day reduction in the time needed to prepare the wound for secondary closure surgery. In one trial on acute wounds, 17 (95 per cent confidence interval (c.i.) 0.02 to 0.32) per cent more wounds appeared to heal with TNP; the number needed to treat was six. This was, however, at the cost of an 11 (95 per cent c.i. 0.01 to 0.21) per cent higher complication rate; the number needed to harm was nine.

CONCLUSION

There is little evidence to support the use of TNP in the treatment of wounds.

Intermittent pneumatic compression for treating venous leg ulcers

BACKGROUND

Intermittent pneumatic compression (IPC) is a mechanical method of delivering compression to swollen limbs that can be used to treat venous leg ulcers and limb swelling due to lymphoedema. This review analyses the evidence for the effectiveness of IPC as a treatment for venous leg ulcers.

OBJECTIVES

To determine whether IPC increases the healing of venous leg ulcers. To determine the effects of IPC on health related quality of life of venous leg ulcer patients.

SEARCH STRATEGY

We searched the Cochrane Wounds Group Specialised Register (December 2007); the Cochrane Central Register of Controlled Trials (CENTRAL) - The Cochrane Library Issue 4, 2007; Ovid MEDLINE - 2006 to November Week 2 2007; Ovid EMBASE - 2006 to 2007 Week 49 and Ovid CINAHL - 2006 to December Week 1 2007.

SELECTION CRITERIA

Randomised controlled studies either comparing IPC with control (sham IPC or no IPC) or comparisons between IPC treatment regimens, in venous ulcer management were included.

DATA COLLECTION AND ANALYSIS

Data extraction and assessment of study quality were undertaken by one author and checked by a second.

MAIN RESULTS

Seven randomised controlled trials (including 367 people in total) were identified. Only one trial reported both allocation concealment and blinded outcome assessment. In one trial (80 people) more ulcers healed with IPC than with dressings (62% vs 28%; p=0.002). Four trials compared IPC with compression against compression alone. The first of these trials (45 people) found increased ulcer healing with IPC plus compression than with compression alone (relative risk for healing 11.4, 95% Confidence Interval 1.6 to 82). The remaining three trials (122 people) found no evidence of a benefit for IPC plus compression compared with compression alone. One small trial (16 people) found no difference between IPC (without additional compression) and compression bandages alone. One trial compared different ways of delivering IPC (104 people) and found that rapid IPC healed more ulcers than slow IPC (86% vs 61%; log rank p=0.003).

AUTHORS' CONCLUSIONS

IPC may increase healing compared with no compression, but it is not clear whether it increases healing when added to treatment with bandages, or if it can be used instead of compression bandages. Rapid IPC was better than slow IPC in one trial. Further trials are required to determine whether IPC increases the healing of venous leg ulcers when used in modern practice where compression therapy is widely used.

Skin grafting for venous leg ulcers

BACKGROUND

Venous leg ulceration is a recurrent, chronic, disabling condition. It affects up to one in 100 adults at some time. Standard treatments are simple dressings and compression bandages or stockings. Sometimes, despite treatment, ulcers remain open for months or years. Sometimes skin grafts are used to stimulate healing. These may be taken, or grown into a dressing, from the patient's own uninjured skin (autografts), or applied as a sheet of bioengineered skin grown from donor cells (allograft). Preserved skin from other animals, such as pigs, has also been used (xenografts).

OBJECTIVES

To assess the effect of skin grafts for treating venous leg ulcers.

SEARCH STRATEGY

We searched the Cochrane Wounds Group Specialised Register (February 2006) and the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2006).

SELECTION CRITERIA

Randomised controlled trials (RCTs) of skin grafts in the treatment of venous leg ulcers.

DATA COLLECTION AND ANALYSIS

Two reviewers independently undertook data extraction and assessment of study quality.

MAIN RESULTS

We identified 15 trials - generally of poor methodological quality - involving 768 participants. In 11 trials participants also received compression bandaging. One trial (31 participants) compared a dressing with an autograft. Three trials (74 participants) compared frozen allografts with dressings, and three trials (47 participants) compared fresh allografts with dressings. Two trials (345 participants) compared tissue-engineered skin (bilayer artificial skin) with a dressing. In two trials (71 participants) a single-layer dermal replacement was compared with standard care. Four trials compared skin grafting techniques: one trial (92 participants) compared autografts with frozen allograft, a second (51 participants) compared a pinch graft (autograft) with a porcine dermis (xenograft), the third (seven participants, 12 ulcers) compared tissue-engineered skin with a split-thickness graft, the fourth (10 participants) compared a fresh allograft with a frozen allograft. The trials comparing bilayer artificial skin with a dressing reported a significantly higher proportion of ulcers healing with artificial skin. There was not enough evidence from the other trials to determine whether other types of skin grafting increased the healing of venous ulcers.

AUTHORS' CONCLUSIONS

Bilayer artificial skin, used in conjunction with compression bandaging, increases the chance of healing a venous ulcer compared with compression and a simple dressing. Further research is needed to assess whether other forms of skin grafts increase ulcer healing.

Diversity and evolution of a newly emerged North American Type 1 porcine arterivirus: analysis of isolates collected between 1999 and 2004

European-like Type 1 porcine reproductive and respiratory syndrome virus (PRRSV) isolates, known as North American (NA) Type 1 PRRSV, appeared in United States (U.S.) swine herds in 1999. Their diversity and evolution were studied over a five-year period by constructing phylogenetic trees using nsp2 and ORF5 sequences of 20 NA Type 1 isolates, including the only known isolate from Hawaii. All but two of the isolates possessed the same 51-nt deletion in nsp2, suggesting a clonal origin. Parsimony and distance analysis showed that viruses could be placed into two distinct sub-clades, which were similar for both nsp2 and ORF5. An incongruity between the two trees identified one isolate, 04-41, as the product of recombination. Recombination analysis using SimPlot identified a break point located downstream of the nsp2/3 junction. Results from this study suggest that NA Type 1 PRRSV in the U.S. is a well-established and rapidly evolving group. However, the forces driving genetic diversity and separation are complex and remain to be elucidated.

Dressings and topical agents for arterial leg ulcers

BACKGROUND

It is estimated that people in industrialised countries have a 1% chance of suffering from a leg ulcer at some time in their life. The majority of leg ulcers are associated with circulation problems; poor blood return in the veins causes venous ulcers (around 70% of ulcers) and poor blood supply to the legs causes arterial ulcers (around 25% of ulcers). Treatment of arterial leg ulcers is directed towards correcting the poor arterial blood supply, for example, by surgically correcting arterial blockages, and by supporting ulcer healing using topical agents (medicines in cream/ointment) and wound dressings. There are a large number of topical agents and wound dressings available and it is unclear what impact these have on ulcer healing.

OBJECTIVES

To determine whether topical agents and wound dressings affect the rate of healing in arterial ulcers. To compare healing rates, costs and patient-centred outcomes between wound dressings and topical agents.

SEARCH STRATEGY

Potential trials were sought through the Specialised Trials Registers of the Cochrane Wounds Group (last searched April 2002), the Cochrane Peripheral Vascular Diseases Group (last searched November 2006) and the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, Issue 4, 2006

SELECTION CRITERIA

Randomised controlled trials (RCTs), or controlled clinical trials (CCTs) of dressings and topical agents for arterial leg ulcers were eligible for inclusion. The participants had to have ulcers that were described as arterial, and the time to healing, proportion completely healed, or rate of reduction in ulcer area had to be reported. All wound dressings and topical agents were eligible for inclusion in this review.

DATA COLLECTION AND ANALYSIS

Information on the participants' characteristics, the interventions, and outcomes, as well as data on the trial methods, such as blinding of patients and clinicians, and allocation concealment were extracted using a standardised data extraction form.

MAIN RESULTS

One trial met the inclusion criteria. This small trial compared ketanserin ointment with vehicle alone, changed twice a day. The trial was too small and for too short a follow-up period to be able to determine whether there was any difference in healing rates.

AUTHORS' CONCLUSIONS

There is insufficient evidence to determine whether the choice of topical agent or dressing affects the healing of arterial leg ulcers. Inadequate description of the people in the one included trial means that the results cannot be easily applied to other clinical populations.

Patient acceptability of larval therapy for leg ulcer treatment: a randomised survey to inform the sample size calculation of a randomised trial

BACKGROUND

A trial was commissioned to evaluate the effectiveness of larval therapy to debride and heal sloughy and necrotic venous leg ulcers. Larval therapy in the trial was to be delivered in either loose or bagged form. Researchers were concerned that resistance to larval therapy may threaten the feasibility of the trial. Additionally there was concern that the use of larval therapy may require a larger effect size in time to healing than originally proposed by the investigators.

METHODS

To formally evaluate patient preferences a survey using two randomly allocated, nurse administered questionnaires was undertaken. Patients were randomised to receive one of the two following questionnaires (i) preferences between loose larvae and standard treatment (hydrogel) or (ii) patient preferences between bagged larvae and standard therapy (hydrogel). The study was undertaken in a Vascular Clinic, in an Outpatients Department of a large teaching hospital in the North of England. The sample consisted of 35 people aged 18 years and above with at least one leg ulcer of venous or mixed (venous and arterial) aetiology.

RESULTS

Approximately 25% of participants would not consider the use of larval therapy as an acceptable treatment option for leg ulcers, regardless of the method of containment. For the patients that would consider the use of larval therapy, different preferences in healing times required to use the therapy were observed depending upon the method of containment. The median response of those participants questioned about bagged larvae found that they would be willing to use this therapy even if they were equally able to achieve healing with the use of hydrogel by 20 weeks. For those participants questioned about the use of loose larvae complete healing would have to have taken place over 17 weeks for them to choose larvae as their preferred option rather than hydrogel. This difference was not significant (p = 0.075).

CONCLUSION

We found no evidence of widespread resistance to the utilisation of larval therapy from patients regardless of the method of larval therapy containment. These methods have the potential to inform sample size calculations where there are concerns of patient acceptability.

Dressings for healing venous leg ulcers

BACKGROUND

Venous leg ulcers, sometimes called varicose or stasis ulcers, are a consequence of damage to the valves in the veins of the legs, leading to raised venous pressure. Venous ulcers are characterised by a cyclical pattern of healing and recurrence. The main treatment is the application of compression, either in the form of compression bandages or hosiery. Dressings are usually applied beneath the compression to aid healing, comfort and to control exudate. Wounds heal quicker in a moist environment and dressings are used to absorb excess fluid or retain fluid in an otherwise dry wound in order to achieve a 'moist wound environment'. There are a large number of dressing products and types available. It is unclear whether particular dressings aid healing of leg ulcers.

OBJECTIVES

To assess the effectiveness of wound dressings for the treatment of venous leg ulcers.

SEARCH STRATEGY

We searched the Cochrane Wounds Group Specialised Register (April 2006) and CENTRAL (issue 1, 2006) and several other electronic databases (up to April 2005). Manufacturers of dressing products were contacted for unpublished studies.

SELECTION CRITERIA

Randomised controlled trials that evaluated dressings for the treatment of venous leg ulcers. There was no restriction in terms of source, date of publication or language. Ulcer healing was the primary endpoint.

DATA COLLECTION AND ANALYSIS

Data from eligible studies were extracted and summarised using a data extraction sheet by two authors independently.

MAIN RESULTS

42 randomised controlled studies were identified that met the inclusion criteria. The main dressing types that were evaluated were hydrocolloids (n = 23), foams (n = 6), alginates (n = 4), hydrogel dressings (n = 6) and a group of miscellaneous dressings (n = 3). In none of the comparisons was there evidence that any one dressing type was better than others in terms of number of ulcers healed. Current evidence does not suggest that hydrocolloids are more effective than simple low adherent dressings used beneath compression (9 trials; relative risk for healing with hydrocolloid 1.09 (95% CI 0.89 to 1.34)). For other comparisons there was insufficient evidence.

AUTHORS' CONCLUSIONS

The type of dressing applied beneath compression has not been shown to affect ulcer healing. For the majority of dressing types there was insufficient data to allow us to draw strong conclusions except for hydrocolloid compared with a low adherent dressing. The result of the meta-analysis indicate no significant difference in healing rates between hydrocolloid dressings and simple, low-adherent dressings when used beneath compression. Decisions regarding which dressing to apply should be based on local costs of dressings and practitioner or patient preferences.

STAT5 represses BCL6 expression by binding to a regulatory region frequently mutated in lymphomas

Deregulated expression of BCL6 is a pathogenic event in many lymphomas. BCL6 blocks cellular differentiation by repressing transcription of its target genes, and this may promote tumorigenesis. Conversely, the transcription factor signal transducers and activators of transcription (STAT)5 promotes differentiation in many systems. STAT5 upregulates a number of genes repressed by BCL6, raising the possibility that STAT5 and BCL6 have opposing roles in transcriptional regulation. Therefore, we sought to determine the effects of STAT5 activation on BCL6 expression and function. We found that activation of STAT5 downregulates BCL6 expression in B-lymphoma cells and other hematopoietic cell lines. We identified two potential STAT-binding regions in the first exon and first intron of BCL6 that fell within regions of high inter-species homology, suggesting conservation of regulatory function. STAT5 can bind inducibly and regulate transcription at one of these regions, identifying BCL6 as a STAT5 target gene. Additionally, STAT5-mediated downregulation of BCL6 results in loss of BCL6 repression of its target genes, confirming that STAT5 is a negative regulator of BCL6 function. The STAT5 responsive region of the BCL6 gene is mutated frequently in B-cell lymphomas, suggesting that loss of the repressive effects of STAT5 on BCL6 might contribute to the pathogenesis of these cancers.

Pressure relieving support surfaces: a randomised evaluation

OBJECTIVES

To determine differences between alternating pressure overlays and alternating pressure replacement mattresses with respect to the development of new pressure ulcers, healing of existing pressure ulcers, patient acceptability and cost-effectiveness of the different pressure-relieving surfaces. Also to investigate the specific additional impact of pressure ulcers on patients' well-being.

DESIGN

A multicentre, randomised, controlled, open, fixed sample, parallel-group trial with equal randomisation was undertaken. The trial used remote, concealed allocation and intention-to-treat (ITT) analysis. The main trial design was supplemented with a qualitative study involving a purposive sample of 20-30 patients who developed pressure ulcers, to assess the impact of the pressure ulcers on their well-being. In addition, a focus group interview was carried out with clinical research nurses, who participated in the PRESSURE (Pressure RElieving Support SUrfaces: a Randomised Evaluation) Trial, to explore the experiences of their role and observations of pressure area care.

SETTING

The study took place in 11 hospital-based research centres within six NHS trusts in England.

PARTICIPANTS

Acute and elective patients aged 55 years or older and admitted to vascular, orthopaedic, medical or care of the elderly wards in the previous 24 hours were investigated.

INTERVENTIONS

Patients were randomised to either an alternating pressure overlay or an alternating pressure mattress replacement, with mattress specifications clearly defined to enable the inclusion of centres using products from different manufacturers, and to exclude hybrid mattress systems (which either combine foam or constant low pressure with alternating pressure in one mattress, or can be used as either an overlay or a replacement mattress).

MAIN OUTCOME MEASURES

Development of a new pressure ulcer (grade < or =2, i.e. partial-thickness wound involving epidermis/dermis only) on any skin site. Also healing of existing pressures ulcers, patient acceptability and cost-effectiveness.

RESULTS

In total, 6155 patients were assessed for eligibility to the trial and 1972 were randomised: 990 to the alternating pressure overlay (989 after one postrandomisation exclusion) and 982 to the alternating pressure mattress replacement. ITT analysis found no statistically significant difference in the proportions of patients developing a new pressure ulcer of grade 2 or above [10.7% overlay patients, 10.3% mattress replacement patients, a difference of 0.4%, 95% confidence interval (CI) -2.3 to 3.1%, p = 0.75]. When logistic regression analysis was used to adjust for minimisation factors and prespecified baseline covariates, there was no difference between the mattresses with respect to the odds of ulceration (odds ratio 0.94, 95% CI 0.68 to 1.29). There was no evidence of a difference between the mattress groups with respect to time to healing (p = 0.86). The Kaplan-Meier estimate of the median time to healing was 20 days for each intervention. More patients allocated overlays requested mattress changes due to dissatisfaction (23.3%) than mattress replacement patients (18.9%, p = 0.02) and more than one-third of patients reporting difficulties associated with movement in bed and getting into or out of bed. There is a higher probability (64%) that alternating mattress replacements are cost-saving; they were associated with lower overall costs (74.50 pounds sterling per patient on average, mainly due to reduced length of stay) and greater benefits (a delay in time to ulceration of 10.64 days on average). Patients' accounts highlighted that the development of a pressure ulcer could be pivotal in the trajectory from illness to recovery, by preventing full recovery or causing varied impacts on their quality of life.

CONCLUSIONS

There is no difference between alternating pressure mattress replacements and overlays in terms of the proportion of patients developing new pressure ulcers; however, alternating pressure mattress replacements are more likely to be cost-saving. The results suggest that when renewing alternating pressure surfaces or ordering equipment within a rental contract, mattress replacements should be specified; however, overlays are acceptable if no replacement mattress is available. Similarly, patient preferences can be supported, without any great increase in risk, if individual patients request an overlay rather than a replacement mattress. Further research could include a randomised controlled trial comparing alternating pressure mattress replacements and high-specification foam mattresses in patients at moderate to high risk; an accurate costing study to understand better how much pressure ulcers cost health and social services in the UK; and trials in higher risk groups of patients. Also future trials should measure time to ulceration as the primary end-point, since this is more informative economically and possibly also from a patient and clinical perspective.

A series of systematic reviews to inform a decision analysis for sampling and treating infected diabetic foot ulcers

OBJECTIVES

To review systematically the evidence on the performance of diagnostic tests used to identify infection in diabetic foot ulcers (DFUs) and of interventions to treat infected DFUs. To use estimates derived from the systematic reviews to create a decision analytic model in order to identify the most effective method of diagnosing and treating infection and to identify areas of research that would lead to large reductions in clinical uncertainty.

DATA SOURCES

Electronic databases covering period from inception of the database to November 2002.

REVIEW METHODS

Selected studies were assessed against validated criteria and described in a narrative review. The structure of a decision analytic model was derived for two groups of patients in whom diagnostic tests were likely to be used.

RESULTS

Three studies that investigated the performance of diagnostic tests for infection on populations including people with DFUs found that there was no evidence that single items on a clinical examination checklist were reliable in identifying infection in DFUs, that wound swabs perform poorly against wound biopsies, and that semi-quantitative analysis of wound swabs may be a useful alternative to quantitative analysis. However, few people with DFUs were included, so it was not possible to tell whether diagnostic performance differs for DFUs relative to wounds of other aetiologies. Twenty-three studies investigated the effectiveness (n = 23) or cost-effectiveness (n = 2) of antimicrobial agents for DFUs. Eight studied intravenous antibiotics, five oral antibiotics, four different topical agents such as dressings, four subcutaneous granulocyte colony stimulating factor (G-CSF), one evaluated oral and topical Ayurvedic preparations and one compared topical sugar versus antibiotics versus standard care. The majority of trials were underpowered and were too dissimilar to be pooled. There was no strong evidence for recommending any particular antimicrobial agent for the prevention of amputation, resolution of infection or ulcer healing. Topical pexiganan cream may be as effective as oral antibiotic treatment with ofloxacin for the resolution of local infection. Ampicillin and sulbactam were less costly than imipenem and cilastatin, a growth factor (G-CSF) was less costly than standard care and cadexomer iodine dressings may be less costly than daily dressings. A decision analytic model was derived for two groups of people, those for whom diagnostic testing would inform treatment--people with ulcers which do not appear infected but whose ulcer is not progressing despite optimal concurrent treatment--and those in whom a first course of antibiotics (prescribed empirically) have failed. There was insufficient information from the systematic reviews or interviews with experts to populate the model with transition probabilities for the sensitivity and specificity of diagnosis of infection in DFUs. Similarly, there was insufficient information on the probabilities of healing, amputation or death in the intervention studies for the two populations of interest. Therefore, we were unable to run the model to inform the most effective diagnostic and treatment strategy.

CONCLUSIONS

The available evidence is too weak to be able to draw reliable implications for practice. This means that, in terms of diagnosis, infection in DFUs cannot be reliably identified using clinical assessment. This has implications for determining which patients need formal diagnostic testing for infection, on whether empirical treatment with antibiotics (before the results of diagnostic tests are available) leads to better outcomes, and on identifying the optimal methods of diagnostic testing. With respect to treatment, it is not known whether treatment with systemic or local antibiotics leads to better outcomes or whether any particular agent is more effective. Limited evidence suggests that both G-CSF and cadexomer iodine dressings may be less expensive than 'standard' care, that ampicillin/sulbactam may be less costly than imipenem/cilastatin, and that an unlicensed cream (pexiganan) may be as effective as oral ofloxacin. Further research is needed to ascertain the characteristics of infection in people with DFUs that influence healing and amputation outcomes, to determine whether detecting infection prior to treatment offers any benefit over empirical therapy, and to establish the most effective and cost-effective methods for detecting infection, as well as the relative effectiveness and cost-effectiveness of antimicrobial interventions for DFU infection.

Systematic review of antimicrobial treatments for diabetic foot ulcers

BACKGROUND

Foot ulcers in diabetes are associated with increased mortality, illness and reduced quality of life. Ulcer infection impairs healing and antimicrobial interventions may cure infection, aid healing and reduce amputation rates.

OBJECTIVES

To systematically review the evidence for antimicrobial interventions for foot ulcers in diabetes.

METHODS

We searched 16 databases, 11 Internet sites, three books, conference proceedings, a journal and bibliographies in November 2002. We included randomized controlled trials (RCTs) or controlled clinical trials (CCTs).

RESULTS

Twenty-three studies investigated the effectiveness or cost-effectiveness of antimicrobial agents: intravenous antibiotics (n = 8); oral antibiotics (n = 5); topical antimicrobials (n = 4); subcutaneous granulocyte-colony stimulating factor (G-CSF) (n = 4); Ayurvedic preparations (n = 1): and sugar vs. antibiotics vs. standard care (n = 1). The trials were small and too dissimilar to be pooled. There is no strong evidence for any particular antimicrobial agent for the prevention of amputation, resolution of infection, or ulcer healing. Pexiganan cream may be as effective as oral ofloxacin for resolution of infection. Ampicillin and sulbactam cost less than imipenem/cilastatin, G-CSF cost less than standard care and cadexomer iodine dressings may cost less than daily dressings.

CONCLUSIONS

The evidence is too weak to recommend any particular antimicrobial agent. Large studies are needed of the effectiveness and cost-effectiveness of antimicrobial interventions.

Systematic review of methods to diagnose infection in foot ulcers in diabetes

AIM

To undertake a systematic review of the diagnostic performance of clinical examination, sample acquisition and sample analysis in infected foot ulcers in diabetes.

METHODS

Nineteen electronic databases plus other sources were searched. To be included, studies had to fulfil the following criteria: (i) compare a method of clinical assessment, sample collection or sample analysis with a reference standard; (ii) recruit diabetic individuals with foot ulcers; (ii) present 2 x 2 diagnostic data. Studies were critically appraised using a 12-item checklist.

RESULTS

Three eligible studies were identified, one each on clinical examination, sample collection and sample analysis. For all three, study groups were heterogeneous with respect to wound type and a small proportion of participants had foot ulcers due to diabetes. No studies identified an optimum reference standard. Other methodological problems included non-blind interpretation of tests and the time lag between index and reference tests. Individual signs or symptoms of infection did not prove to be useful tests when assessed against punch biopsy as the reference standard. The wound swab did not perform well when assessed against tissue biopsy. Semiquantitative analysis of wound swab might be a useful alternative to quantitative analysis. The limitations of these findings and their impact on recommendations from relevant clinical guidelines are discussed.

CONCLUSION

Given the importance of this topic, it is surprising that only three eligible studies were identified. It was not possible to describe the optimal methods of diagnosing infection in diabetic patients with foot ulceration from the evidence identified in this systematic review.

An exploration of the use of ultrasound in the treatment of chronic venous leg ulcers

A nurse-led multicentre randomised controlled trial will compare the clinical effectiveness of weekly ultrasound combined with standard care in the treatment of 'hard-to-heal' venous leg ulcers. Recruitment started last autumn.

Skin grafting for venous leg ulcers

BACKGROUND

Venous leg ulceration is a common and disabling condition which often recurs. It affects up to one in 100 adults at some time. The usual treatments are simple dressings and compression bandages or stockings. Unfortunately, in some cases this treatment is unsuccessful, with ulcers remaining open for months or years. Sometimes skin grafts are used to stimulate healing. These skin grafts may be taken from the patient's own uninjured skin, may be grown from the patient's skin cells into a dressing (autografts), or applied as a sheet of bioengineered skin grown from donor cells (allograft). Preserved skin from other animals, such as pigs, has also been used; these grafts are known as xerografts.

OBJECTIVES

To assess the effect of skin grafts for treating venous leg ulcers.

SEARCH STRATEGY

We searched the Cochrane Wounds Group Specialised Register (June 2004) and the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 2, 2004).

SELECTION CRITERIA

Randomised controlled trials (RCTs) of skin grafts in the treatment of venous leg ulcers.

DATA COLLECTION AND ANALYSIS

Two reviewers independently undertook data extraction and assessment of study quality.

MAIN RESULTS

Nine trials of skin grafts for venous leg ulcers were identified, involving 579 participants. The trials were generally of poor methodological quality. In eight trials participants also received compression bandaging. Two trials (98 participants) evaluated split thickness autografts (one against a dressing and one against a xerograft), four trials (119 participants) evaluated cultured keratinocyte grafts (3 allografts and 1 autograft) , two compared tissue engineered skin (bilayer artificial skin) with a dressing (345 participants), and one compared it with a split thickness skin graft (7 participants, 13 ulcers). The trials comparing bilayer artificial skin with a dressing reported a significantly higher proportion of ulcers healing with artificial skin. There was not enough evidence from the other trials to determine whether other types of skin grafting increased the healing of venous ulcers.

AUTHORS' CONCLUSIONS

There is evidence that a bilayer artificial skin, used in conjunction with compression bandaging, increases the chance of healing a venous ulcer compared with compression and a simple dressing. Further research is needed to assess whether other forms of skin grafts increase ulcer healing.

VenUS I: a randomised controlled trial of two types of bandage for treating venous leg ulcers

OBJECTIVES

To compare the clinical and cost-effectiveness of two different compression bandages for the healing of venous leg ulcers.

DESIGN

A pragmatic, randomised controlled trial with an economic evaluation.

SETTING

Community, district nurse-led services; community leg ulcer clinics; hospital leg ulcer clinics with community outreach. A range of urban and rural settings in England and Scotland.

PARTICIPANTS

Patients with a venous leg ulcer of at least 1-week's duration, at least 1 cm in length or width and an ankle:brachial pressure index of at least 0.8.

INTERVENTIONS

The four-layer bandage (4LB) (which is multilayer elastic compression) compared with the short-stretch bandage (SSB) (multilayer, inelastic compression).

MAIN OUTCOME MEASURES

The primary end-point was complete healing of all the ulcers on the trial leg. Secondary outcomes were the proportion of patients healed at 12 and 24 weeks, rate of recurrence, costs of leg ulcer treatment and quality of life.

RESULTS

Between April 1999 and December 2000 the trial recruited 387 people aged from 23 to 97 years at trial entry. The majority of patients in this trial (82%; 316/387) had a reference ulcer of area </=10 cm(2). To test the difference over time of Kaplan--Meier curves for the two bandage groups, the distribution of the cumulative times to healing of individuals in the two trial groups was compared using the log-rank test. The difference in the distribution of cumulative healing times between the individuals in the two groups was not statistically significant at the 5% level. Adjusting for the effects of variables which may influence healing (centre, baseline ulcer area, duration, episodes, ankle mobility, weight) in a Cox proportional hazards model, a statistically significant treatment effect in favour of the 4LB was identified. At any point in time, the probability of healing for individuals in the SSB treatment arm is significantly lower than that for people treated with the 4LB. Our base case economic analysis showed that the 4LB is the dominant strategy, that is, it is associated with a greater health benefit and lower costs than the SSB, although the differences are not statistically significant. This result is explained largely by the greater number of community nurse visits required by participants in the short-stretch arm.

CONCLUSIONS

The 4LB, which is currently the UK standard compression bandage for people with venous leg ulcers, was more clinically and cost-effective than the SSB. The bandage costs were less important than the costs of treatment visits, and patients in SSBs required more treatment overall. Generally, this trial supports the use of the 4LB in preference to the SSB. Recommendations for future research include: exploration of the relationship between bandager skill, application technique and ulcer healing; the relative cost-effectiveness of community leg ulcer clinics; and the study of nurse decision-making in venous ulcer management.

Economic analysis of VenUS I, a randomized trial of two bandages for treating venous leg ulcers

BACKGROUND

The study investigated the cost-effectiveness of four-layer and short-stretch compression bandages for treating venous leg ulcers.

METHODS

Cost-effectiveness and cost-utility analyses were performed using patient-level data collected alongside the VenUS I leg ulcer study. The perspective for the economic analysis was that of the UK National Health Service (NHS) and Personal Social Service. The time horizon for the analysis was 1 year after recruitment. Health benefit was measured as differences in ulcer-free days and quality-adjusted life years (QALYs).

RESULTS

The mean healing time for ulcers treated with four-layer bandages was 10.9 (95 per cent confidence interval (c.i.) -6.8 to 29.1) days less than that for ulcers treated with short-stretch bandages. Mean average difference in QALYs between compression systems was -0.02 (95 per cent c.i. -0.08 to 0.04). The four-layer bandage cost a mean of pound 227.32 (95 per cent c.i. pound 16.53 to pound 448 .30) less per patient per year than the short-stretch bandage.

CONCLUSION

On average, four-layer bandaging was associated with greater health benefits and lower costs than short-stretch bandaging.

Randomized clinical trial of four-layer and short-stretch compression bandages for venous leg ulcers (VenUS I)

BACKGROUND

A randomized clinical trial was undertaken to determine the relative effectiveness of four-layer and short-stretch bandaging for venous ulceration.

METHODS

A total of 387 adults with a venous ulcer, who were receiving leg ulcer treatment either in primary care or as a hospital outpatient, were recruited to this parallel-group open study and randomized to either four-layer or short-stretch bandages. Follow-up continued until the patient's reference leg was ulcer free or for a minimum of 12 months. The primary endpoint was time to complete healing of all ulcers on the reference leg. Secondary outcomes included proportion of ulcers healed, health-related quality of life, withdrawals and adverse events. Analysis was by intention to treat.

RESULTS

Unadjusted analysis identified no statistically significant difference in median time to healing: 92 days for four-layer and 126 days for short-stretch bandages. However, when prognostic factors were included in a Cox proportional hazards regression model, ulcers treated with the short-stretch bandage had a lower probability of healing than those treated with the four-layer bandage: hazard ratio 0.72 (95 per cent confidence interval 0.57 to 0.91). More adverse events and withdrawals were reported with the short-stretch bandage.

CONCLUSION

Venous leg ulcers treated using a four-layer bandage healed more quickly than those treated with a short-stretch bandage.

Dressings and topical agents for arterial leg ulcers

BACKGROUND

It is estimated that people in industrialised countries have a 1% chance of suffering from a leg ulcer at some time in their life. The majority of leg ulcers are associated with circulation problems; poor blood return in the veins causes venous ulcers (around 70% of ulcers) and poor blood supply to the legs causes arterial ulcers (around 25% of ulcers). Treatment of arterial leg ulcers is directed towards correcting the poor arterial blood supply, for example, by surgically correcting arterial blockages, and by supporting ulcer healing using topical agents (medicines in cream/ointment) and wound dressings. There are a large number of topical agents and wound dressings available and it is unclear what impact these have on ulcer healing.

OBJECTIVES

To determine whether topical agents and wound dressings affect the rate of healing in arterial ulcers. To compare healing rates, costs and patient-centred outcomes between wound dressings and topical agents.

SEARCH STRATEGY

Publications describing (or potentially describing) randomised controlled trials (RCTs), or controlled clinical trials (CCTs) of dressings and topical agents for arterial leg ulcers were sought through the Specialised Trials Registers of the Cochrane Wounds Group (last searched January 2002) and the Cochrane Peripheral Vascular Diseases Group (last searched April 2002).

SELECTION CRITERIA

RCTs or CCTs (trials with non-randomised concurrent comparison groups) were eligible for inclusion. The participants had to have ulcers that were described as arterial, and the time to healing, proportion completely healed, or rate of reduction in ulcer area had to be reported. All wound dressings and topical agents were eligible for inclusion in this review.

DATA COLLECTION AND ANALYSIS

Information on the participants' characteristics, the interventions, and outcomes, as well as data on the trial methods, such as blinding of patients and clinicians, and allocation concealment were extracted using a standardised data extraction form.

MAIN RESULTS

One trial met the inclusion criteria. This small trial compared ketanserin ointment with vehicle alone, changed twice a day. The trial was too small and for too short a follow-up period to be able to determine whether there was any difference in healing rates.

REVIEWER'S CONCLUSIONS

There is insufficient evidence to determine whether the choice of topical agent or dressing affects the healing of arterial leg ulcers. Inadequate description of the people in the one included trial means that the results cannot be easily applied to other clinical populations.

Topical agents or dressings for pain in venous leg ulcers

BACKGROUND

Venous leg ulcers affect up to 1 per cent of people at some time in their life. These ulcers are often painful and some clinicians choose dressings and topical treatments (analgesia/ local anaesthetic) to reduce the pain both during and between dressing changes.

OBJECTIVES

To assess the effectiveness of dressings, local anaesthetics or topical analgesia for pain relief in venous leg ulceration.

SEARCH STRATEGY

Cochrane Wounds Group Register and the Cochrane Collaboration Field in Complementary Medicine were searched in June 2002. Cochrane Pain Palliative and Supportive Care Group and Cochrane Wounds Group strategy were combined and used.

SELECTION CRITERIA

All randomised controlled trials which evaluated local interventions used to relieve venous leg ulcer pain were considered. Pain was defined as either persistent pain or pain at dressing changes or debridement.

DATA COLLECTION AND ANALYSIS

Eligibility for inclusion was confirmed by two reviewers who independently assessed the potential trials. Details of eligible studies were summarised using a data extraction sheet which was checked by the second reviewer.

MAIN RESULTS

No trials evaluating interventions for persistent pain were identified for the initial review in 1999 nor the update in 2002. Three trials were included in the 1999 review comparing a eutectic mixture of local anaesthetic (EMLA) versus placebo for pain at debridement. In 2002 a further 3 trials were available (6 trials in total with 317 patients). The studies were considered sufficiently similar to pool and meta analysis found a statistically significant reduction in debridement pain scores with EMLA 5% cream. EMLA was associated with a reduction in pain scores (measured on a 100 mm scale) of 20.6 mm (95% Confidence Interval 29.11-12.19). One small trial measured healing as an outcome and found no difference in numbers of ulcers healed at the end of the study.

REVIEWER'S CONCLUSIONS

EMLA provides effective pain relief for venous leg ulcer debridement however, the effect of the product on ulcer healing is unknown. Research is required to determine the impact of debridement and of EMLA on ulcer healing. There were no trials addressing the treatment of persistent pain (between and at dressing changes) and further research is warranted.

Use of compression hosiery in venous leg ulceration

Venous leg ulceration is a common problem in older people that adversely affects their quality of life. It is also a major cause of morbidity for many patients in hospital and community settings. Patients experience considerable pain and distress as a result of this condition and annual costs to the NHS are high. However, good nursing management and the correct use of compression therapy can lead to faster healing rates (Effective Health Care 1997), and reduced nursing time. This article discusses the use of compression hosiery in the prevention and treatment of venous leg ulcers.

Measurement of body fat using leg to leg bioimpedance

AIMS

(1) To validate a leg to leg bioimpedance analysis (BIA) device in the measurement of body composition in children by assessment of its agreement with dual energy x ray absorptiometry (DXA) and its repeatability. (2) To establish a reference range of percentage body fat in Hong Kong Chinese children.

METHODS

Sequential BIA and DXA methods were used to determine body composition in 49 children aged 7-18 years; agreement between the two methods was calculated. Repeatability for the BIA method was established from duplicate measurements. Body composition was then determined by BIA in 1139 girls and 1243 boys aged 7-16 years, who were randomly sampled in eight local primary and secondary schools to establish reference ranges.

RESULTS

The 95% limits of agreement between BIA and DXA methods were considered acceptable (-3.3 kg to -0.5 kg fat mass and -3.9 to 0.6% body fat). The percentage body fat increased with increasing age. Compared to the 1993 Hong Kong growth survey, these children had higher body mass index. Mean (SD) percentage body fat at 7 years of age was 17.2% (4.4%) and 14.0% (3.4%) respectively for boys and girls, which increased to 19.3% (4.8%) and 27.8% (6.3%) at age 16.

CONCLUSION

Leg to leg BIA is a valid alternative method to DXA for the measurement of body fat. Provisional reference ranges for percentage body fat for Hong Kong Chinese children aged 7-16 years are provided.

A 10-kDa structural protein of porcine reproductive and respiratory syndrome virus encoded by ORF2b

The major structural proteins of porcine reproductive and respiratory syndrome virus (PRRSV) are derived from ORFs 5, 6, and 7. Western blots of sucrose gradient-purified virions and PRRSV-infected MARC-145 cells, probed with immune pig serum, showed the presence of an additional 10-kDa protein. Nucleotide sequence analysis of North American PRRSV isolate SDSU-23983 revealed a small ORF within ORF2, named ORF2b, which, when translated, produced a 73-amino-acid nonglycosylated protein. Recombinant 2b protein expressed by a baculovirus clone, AcVR2, comigrated with the 10-kDa virus-associated protein. The loss of 10-kDa protein immunoreactivity after absorption of immune sera with lysates from AcVR2-infected insect cells demonstrated that the 2b and 10-kDa proteins are immunologically similar. Immunoblots were also used for the detection of anti-2b activity in serum samples from experimentally infected adult pigs. Antibodies against PRRSV were apparent by 14 days postinfection, followed by anti-2b activity and serum neutralizing activity. The putative ORF2b start codon is only 6 nucleotides downstream of the adenine of the ORF2a start codon. The expression of ORF2a and 2b as enhanced green fluorescent fusion proteins showed that both proteins were translated; however, the ORF2b was preferentially expressed. These results suggest that the 2b protein is virion associated and the principal product of ORF2.

International Child Care Practices Study: infant sleep position and parental smoking

The International Child Care Practices Study (ICCPS) collected descriptive data from 21 centres in 17 countries. In this report, data are presented on the key sudden infant death syndrome (SIDS) risk factors of infant sleep position and parental smoking.

METHODS

Using a standardised protocol, parents of infants were surveyed at birth by interview, and at 3 months of age mainly by postal questionnaire. Data entry and descriptive analysis were undertaken with Epi Info. Centres were grouped according to geographic location. Also indicated was the level of SIDS awareness in the community, i.e. whether any campaigns or messages to "reduce the risks of SIDS" were available at the time of the survey.

RESULTS

Birth interview data were available for 5488 individual families, and 4656 (85%) returned questionnaires at 3 months. Overall, 52.5% (95% CI, 43.5-61.3) of infants were placed in the supine or back sleep position, 37.8% (95% CI, 30.6-45.7) in the side position and 13% (95% CI, 9.3-17.9) in the prone or front position. The prevalence of supine sleeping ranged from 14% (Santiago, Chile) to 89% (Tokyo/Yokohama, Japan). The prevalence of reported smoking was between 0% and 34% for mothers and 10% and 64% for fathers. In samples from Western countries, there was a trend for rates of maternal smoking to be similar to paternal smoking, whereas in other samples, low rates of maternal smoking contrasted with high rates of paternal smoking.

CONCLUSIONS

These data highlight considerable variations and interesting patterns in the prevalence of these two important SIDS risk factors in these diverse samples. Impressive differences in rates of smoking within and between these communities may reflect different stages of the inevitable progression of the smoking epidemic, but may also provide some encouragement that reduction in smoking rates, in both mothers and fathers, is possible.

Systematic reviews of wound care management: (5) beds; (6) compression; (7) laser therapy, therapeutic ultrasound, electrotherapy and electromagnetic therapy

BACKGROUND

Chronic wounds such as leg ulcers, diabetic foot ulcers and pressure sores are common in both acute and community healthcare settings. The prevention and treatment of these wounds involves many strategies: pressure-relieving beds, mattresses and cushions are universally used as measures for the prevention and treatment of pressure sores; compression therapy in a variety of forms is widely used for venous leg ulcer prevention and treatment; and a whole range of therapies involving laser, ultrasound and electricity is also applied to chronic wounds. This report covers the final three reviews from a series of seven.

AIMS

To assess the clinical effectiveness and cost- effectiveness of: (1) pressure-relieving beds, mattresses and cushions for pressure sore prevention and treatment; (2) compression therapy for the prevention and treatment of leg ulcers; (3) low-level laser therapy, therapeutic ultrasound, electrotherapy and electromagnetic therapy for the treatment of chronic wounds. METHODS - DATA SOURCES: Nineteen electronic databases, including MEDLINE, CINAHL, EMBASE and the Cochrane Controlled Trials Register (CENTRAL), were searched. Relevant journals, conference proceedings and bibliographies of retrieved papers were handsearched. An expert panel was also consulted.

METHODS - STUDY SELECTION

Randomised controlled trials (RCTs) which evaluated these interventions were eligible for inclusion in this review if they used objective measures of outcome such as wound incidence or healing rates. RESULTS - BEDS, MATTRESSES AND CUSHIONS FOR PRESSURE SORE PREVENTION AND TREATMENT: A total of 45 RCTs were identified, of which 40 compared different mattresses, mattress overlays and beds. Only two trials evaluated cushions, one evaluated the use of sheepskins, and two looked at turning beds/kinetic therapy. RESULTS - COMPRESSION FOR LEG ULCERS: A total of 24 trials reporting 26 comparisons were included (two of prevention and 24 of treatment strategies). RESULTS - LOW-LEVEL LASER THERAPY, THERAPEUTIC ULTRASOUND, ELECTROTHERAPY AND ELECTROMAGNETIC THERAPY: Four RCTs of laser (for venous leg ulcers), 10 of therapeutic ultrasound (for pressure sores and venous leg ulcers), 12 of electrotherapy (for ischaemic and diabetic ulcers, and chronic wounds generally) and five of electromagnetic therapy (for venous leg ulcers and pressure sores) were included. Studies were generally small, and of poor methodological quality. CONCLUSIONS (1) Foam alternatives to the standard hospital foam mattress can reduce the incidence of pressure sores in people at risk, as can pressure-relieving overlays on the operating table. One study suggests that air-fluidised therapy may increase pressure sore healing rates. (2) Compression is more effective in healing venous leg ulcers than is no compression, and multi-layered high compression is more effective than single-layer compression. High-compression hosiery was more effective than moderate compression in preventing ulcer recurrence. (3) There is generally insufficient reliable evidence to draw conclusions about the contribution of laser therapy, therapeutic ultrasound, electrotherapy and electromagnetic therapy to chronic wound healing.

Postnatal iron status of Hong Kong Chinese women in a longitudinal study of maternal nutrition

OBJECTIVE

To report postnatal iron nutritional status of Hong Kong Chinese women during the first 6 months postpartum.

DESIGN AND SUBJECTS

A longitudinal study examining postnatal calcium and iron status of Hong Kong Chinese breastfeeding and formula-feeding women was conducted during 1998. Postpartum women aged 20-40 y, with no bone or blood disorders were recruited and interviewed at 0 (baseline), 2, 6 weeks, 3 and 6 months postpartum. Dietary intake was assessed by a 3 day dietary record and cross checked by a 24 h recall. Complete blood count and serum ferritin level were measured to assess anaemia and iron status. In this report, subjects were divided into an anaemic group (haemoglobin level < 10 g/dl) and a non-anaemic group (haemoglobin level > or = 10 g/dl) according to baseline haemoglobin levels.

RESULTS

At baseline, 13/47 (27.7%) subjects were anaemic. Two of these 13 anaemic subjects were still anaemic at 3 and 6 months postpartum. Anaemic subjects showed significantly (P < 0.01) greater amounts of blood loss and a higher rate of primary postpartum haemorrhage than the non-anaemic subjects. Daily food intake and dietary nutrient intake did not differ significantly between the two groups. During the first 6 weeks postpartum, subjects in both groups consumed more poultry and egg, and comparable amounts of meat, compared with women in the Hong Kong general population. Iron and vitamin C intakes for the majority of subjects reached 60% of the US Recommended Daily Allowances. Regression analysis suggested that the rate of change in haemoglobin level in the first 6 weeks postpartum was positively correlated with baseline MCV level and serum ferritin level, but negatively correlated with baseline haemoglobin level.

CONCLUSIONS

Blood loss at delivery is an important factor for postpartum anaemia. Postnatal recovery of iron status of this group of women appeared to be more related to physiological factors than to dietary factors. The role of diet as well as other physiological changes in postpartum women requires further investigation. Finding ways to minimise blood loss at delivery could be the most practical strategy to reduce the rate of postpartum anaemia.

SPONSORSHIP

CSM was supported by a research studentship from the Research Grants Council, Hong Kong.

International Child Care Practices Study: infant sleeping environment

BACKGROUND

The International Child Care Practices Study (ICCPS) has collected descriptive data from 21 centres in 17 countries. In this report, data are presented on the infant sleeping environment with the main focus being sudden infant death syndrome (SIDS) risk factors (bedsharing and infant using a pillow) and protective factors (infant sharing a room with adult) that are not yet well established in the literature.

METHODS

Using a standardised protocol, parents of infants were surveyed at birth by interview and at 3 months of age mainly by postal questionnaire. Centres were grouped according to geographic location. Also indicated was the level of SIDS awareness in the community, i.e. whether any campaigns or messages to "reduce the risks of SIDS" were available at the time of the survey.

RESULTS

Birth interview data were available for 5488 individual families and 4656 (85%) returned questionnaires at 3 months. Rates of bedsharing varied considerably (2-88%) and it appeared to be more common in the samples with a lower awareness of SIDS, but not necessarily a high SIDS rate. Countries with higher rates of bedsharing appeared to have a greater proportion of infants bedsharing for a longer duration (>5 h). Rates of room sharing varied (58-100%) with some of the lowest rates noted in centres with a higher awareness of SIDS. Rates of pillow use ranged from 4% to 95%.

CONCLUSIONS

It is likely that methods of bedsharing differ cross-culturally, and although further details were sought on different bedsharing practices, it was not possible to build up a composite picture of "typical" bedsharing practices in these different communities. These data highlight interesting patterns in child care in these diverse populations. Although these results should not be used to imply that any particular child care practice either increases or decreases the risk of SIDS, these findings should help to inject caution into the process of developing SIDS prevention campaigns for non-Western cultures.

Detection and duration of porcine reproductive and respiratory syndrome virus in semen, serum, peripheral blood mononuclear cells, and tissues from Yorkshire, Hampshire, and Landrace boars

Because transmission of porcine reproductive and respiratory syndrome virus (PRRSV) can occur through boar semen, it is important to identify persistently infected boars. However, even for boars given the same PRRSV strain and dose, variability in the duration of viral shedding in semen has been observed, suggesting that host factors are involved in PRRSV persistence. To determine whether there are host genetic factors, particularly litter and breed differences related to the persistence of PRRSV, 3 litters from 3 purebred swine breeds were used for this study. It was also determined whether PRRSV could be detected for a longer period of time in serum, semen, or peripheral blood mononuclear cells (PBMC) and if PRRSV could still be detected in tissues after these antemortem specimens were PRRSV negative for a minimum of 2-3 weeks. Three Hampshire, 3 Yorkshire, and 2 Landrace PRRSV-naive boars were obtained and inoculated intranasally with a wild-type PRRSV isolate (SD-23983). All boars within each breed were from the same litter, and litters were within 9 days of age. Serum and PBMC were collected twice weekly from each boar and analyzed for the presence of PRRSV by virus isolation and the polymerase chain reaction (PCR). Serum was also used to obtain virus neutralization titers and enzyme-linked immunosorbent assay S/P values. Semen was collected twice weekly from 7 of 8 boars and analyzed by PCR. After all specimens were PRRSV negative for a minimum of 2-3 weeks, each boar was euthanized, and 21 tissues plus saliva, serum, feces, and urine were collected. All postmortem specimens were evaluated by virus isolation. Specimens that were PRRSV negative by virus isolation were then evaluated by PCR. The mean number of days (+/-SD) for the duration of PRRSV shedding in semen was 51+/-26.9 days, 7.5+/-4.9 days, and 28.3+/-17.5 days for Landrace, Yorkshire, and Hampshire boars, respectively. Because of small sample sizes and large SDs, the differences in duration of PRRSV shedding in semen between breeds were not considered significant. However, the trend suggested that Yorkshire boars were more resistant to PRRSV shedding in semen than were Landrace boars, requiring further investigation using a larger numbers of boars. PRRSV was detected for a longer period in semen than in serum or PBMC in 4 of 7 boars. Viremia could be detected for a longer period in serum than in PBMC in 6 of 8 boars. After a minimum of 2-3 weeks of PRRSV-negative serum, semen, and PBMC, PRRSV could still be detected in the tonsil of 3 of 8 boars by virus isolation, indicating that boars still harbor PRRSV within the tonsil even though antemortem specimens are PRRSV negative.

Preliminary results of a pilot program on depression in patients with congestive heart failure

While the sample size is too small to warrant conclusions, these preliminary results suggest that assessment of depression would be worthwhile for patients diagnosed with congestive heart failure. 32 out of 54 patients with congestive heart failure scored positive for depression. When psychiatric treatment was given, there was a decrease in depressive symptoms for four of the six patients at the 6-mo, retest. A decrease in depressive symptoms was found for two of the six untreated patients, and the remaining four patients had worse scores on the Zung Depression Inventory. Primary care physicians, who typically meet with such patients regularly, are encouraged to screen for depression, as their clinical assessments in this study were associated with scores on the Zung Depression Inventory. These observations support a full scale investigation with a much larger sample size and a requisite medical cost comparison.

Intermittent pneumatic compression for treating venous leg ulcers

BACKGROUND

Intermittent pneumatic compression (IPC) is a mechanical method of delivering compression to swollen limbs. This technique has been used to treat venous leg ulcers and limb swelling due to lymphoedema. The effectiveness of IPC, and the appropriate duration and frequency of IPC therapy are unknown as are the differences between various types of IPC. This review analyses the evidence for the effectiveness of IPC as a treatment for venous leg ulcers.

OBJECTIVES

To determine whether IPC increases the healing of venous leg ulcers. To determine the effects of IPC on health related quality of life of venous leg ulcer patients.

SEARCH STRATEGY

The Cochrane Wound Group Trials Register was searched for RCTs of intermittent pneumatic compression in February 2001. Journals and relevant conference proceedings were searched by hand. Companies were also contacted for relevant unpublished data or ongoing studies.

SELECTION CRITERIA

Randomised controlled studies either comparing IPC with control (sham IPC or no IPC) or comparisons between IPC treatment regimens, in venous ulcer management were included.

DATA COLLECTION AND ANALYSIS

Data extraction and assessment of study quality were undertaken by two reviewers independently.

MAIN RESULTS

Four randomised controlled trials were identified. One small trial (45 people) found increased ulcer healing with IPC plus compression than with compression alone (relative risk for healing 11.4, 95% Confidence Interval 1.6 to 82). Two small trials with a total of 75 people found no evidence of a benefit for IPC plus compression compared with compression alone. One small trial (16 people) found no difference between IPC (without additional compression) and compression bandages alone.

REVIEWER'S CONCLUSIONS

Further trials are required to determine whether IPC increases the healing of venous leg ulcers.

Physician attitudes toward and prevalence of the hospitalist model of care: results of a national survey

PURPOSE

We sought to determine the availability and utilization of, as well as physician attitudes toward, the hospitalist model in the United States.

SUBJECTS AND METHODS

Using a telephone survey, we asked physicians who were board certified in internal medicine about their inpatient practice arrangements, the availability of hospitalist services, and their attitudes toward the hospitalist model. All physicians were generalists in active clinical practice. Using multivariable methods, we determined factors associated with attitudes toward the hospitalist model.

RESULTS

We were able to contact 787 of 2,829 physicians who were randomly selected from a national list of board-certified internists, of whom 400 agreed to participate. Most respondents were familiar with the term "hospitalist" and had hospitalist services available in their community, and 28% used hospitalists for their inpatients. Few (2%) reported the presence of the "mandatory" hospitalist model. Physicians reported that the model was more commonly available in Western states (84% vs. 55% to 63% in other regions, P<0.0001). Seventy-three percent thought hospitalist systems would reduce continuity of care. Only 28% thought that patients would prefer care from an inpatient specialist, but 51% thought patients might get better care, and 47% thought patients might get more cost-effective care in a hospitalist system. In multivariable models, physicians who were in solo practice, those in specialties with more inpatient practice, and those who had more patients hospitalized each month responded more negatively about the model, whereas those with hospitalists in their community were more positive.

CONCLUSIONS

Although agreeing that quality of care and efficiency might be improved, physicians were concerned about patient-doctor relationships and patient satisfaction in a hospitalist model. Future studies should determine the effect of the hospitalist model on these outcomes.

Increased density of gutta-percha using a controlled heat instrument with lateral condensation

The purpose of this study was to compare quantitatively the density of standard cold lateral gutta-percha condensation and warm lateral gutta-percha condensation using the System B heating instrument in a low-heat warm lateral condensation technique in an artificial root canal in vitro. Thirty-degree simulated root canals in 30 transparent acrylic blocks were instrumented using Gates-Glidden burs and Quantec (NT Company, Chattanooga, TN) rotary files. The canals were then obturated with gutta-percha using standard cold lateral condensation without sealer. Warm lateral condensation without sealer using the System B instrument at 101 degrees C was then performed on the same 30 canals. A second treatment of warm lateral condensation was then applied to these same canals. The blocks were weighed after the initial canal preparation and after each obturation treatment. Results showed warm lateral condensation of gutta-percha using the System B resulted in a significant increase in density by weight when compared with standard cold lateral condensation. A 23.97% increase in weight was realized after the first heat application, compared with standard lateral condensation. A second heat application produced an additional 2.59% increase in weight over that produced by the first heat application. Data were analyzed using a t test for repeated measures. Both increases were statistically significant (p < 0.001). Warm lateral condensation using the System B instrument results in denser gutta-percha fills by weight when compared with standard cold lateral condensation.

Measurement of immunoglobulin G, A and M concentrations in boar seminal plasma

How the immune system relates to the boar reproductive tract is not well defined. This is an important area of study because disease-causing agents may be transmitted through boar semen. We have previously identified porcine reproductive and respiratory syndrome virus (PRRSV) in boar semen and wanted to identify PRRSV-specific antibodies within seminal plasma. However, literature documenting total immunoglobulin concentration or the predominant immunoglobulin isotype in boar semen was not available. Therefore, we developed a sandwich enzyme-linked immunoassay (ELISA) to quantitate total IgG, IgA and IgM in seminal plasma from 16 healthy, nonvaccinated, adult boars (n = 102 semen samples). In seminal plasma, IgG was the predominant isotype followed by IgA and IgM. Mean levels +/- the standard deviation followed by the 95% confidence interval of IgG, IgA and IgM were 23.2 +/- 14 microg/mL (15.5 to 31.0), 4.8 +/- 2.5 microg/mL (3.5 to 6.2) and 3.7 +/- 1.7 microg/mL (2.7 to 4.7), respectively. These concentrations of immunoglobulins in seminal plasma were considerably lower than in other swine secretions, which might allow for the survival of infectious agents in boar semen.

The synthesis and SAR of rhodanines as novel class C beta-lactamase inhibitors

Beta-lactam antibiotics such as the cephalosporins and penicillins have diminished clinical effectiveness due to the hydrolytic activity of diverse beta-lactamases, especially those in molecular classes A and C. A structure activity relationship (SAR) study of a high-throughput screening lead resulted in the discovery of a potent and selective non-beta-lactam inhibitor of class C beta-lactamases.