Traumatic renal artery dissection identified with dynamic helical computed tomography

Intimal tears in the renal arteries typically result from traumatic mechanisms that produce rapid deceleration. These injuries usually progress to secondary thrombosis of the vessel. When the tear leads to dissection with luminal stenosis, early diagnosis and repair will preserve parenchymal function. Computed tomography has replaced intravenous pyelography as the radiographic study of choice for renal trauma. We present two patients with unilateral delay of renal contrast enhancement during dynamic helical computed tomography scan due to arterial stenosis from intimal dissection confirmed with arteriography. Both vessel injuries were successfully managed with endovascular stent placement. No previous description of this diagnostic strategy is reported in the literature.

Chemiluminescence detection of ATP release from red blood cells upon passage through microbore tubing

A novel approach for the determination of adenosine triphosphate (ATP) released from red blood cells (RBCs) after passage through microbore capillaries is described. ATP is often released from RBCs in vessels and has been linked to the production of nitric oxide, a known vasodilator. The system described here uses a syringe pump to deliver microliter flow rates (5-15 microl min(-1)) of reagent and sample through fused silica capillary tubing of varying dimensions (25-75 microm) to a photomultiplier tube. The released ATP is characterized by the detection of chemiluminescent emission from the luciferin-luciferase reaction. The amount of ATP released is directly proportional to the number of RBCs injected into the system. Results also suggest that the amount of released ATP decreases from 6.9 microM to 1.4 microM as the tubing diameter is increased from 25 microm to 75 microm. An investigation of capillary lengths ranging from 15 to 35 cm resulted in ATP concentrations of 1.5 microM to 2.4 microM being released. Results also indicate that increases in flow rate also induce increased amounts of ATP release. These results are consistent with those of previous systems attempting to model the physiological release of ATP from red blood cells.

A comparison of the prevalence of respiratory illness and non-specific health symptoms in two Victorian cities

OBJECTIVE

To compare the prevalence of respiratory illness and non-specific health symptoms among adults and children aged 4-15 years living in Portland and Warrnambool, Victoria.

METHODS

A postal survey of 3,903 adults in Portland and Warrnambool systematically selected from the electoral roll was undertaken. Both an adults and children's questionnaire were enclosed in the mailing to each adult. If there were children aged 4-15 years in the household, an adult was asked to complete a questionnaire for the child who would next celebrate a birthday. Questionnaires were returned by 2,111 adults (54%) and for 585 children.

RESULTS

No significant differences in the prevalence of self-reported asthma or wheeze were observed among adults or children residing in Portland and Warrnambool. The likelihood of itchy eyes, skin rash and stuffy nose was significantly higher in Portland adults and children compared with those in Warrnambool. Dry cough at night was increased among Portland children, but not significantly so.

CONCLUSIONS

Higher rates of non-specific symptoms were observed in Portland but from a cross-sectional survey such as this, it is not possible to identify the cause of these higher rates. They may be related to environmental factors such as pollens or emissions from aluminium production, fertiliser production or bulk handling activities on the wharf, or they may be attributable to other factors such as response or recall bias.

Fourth-generation enzyme-linked immunosorbent assay for the simultaneous detection of human immunodeficiency virus antigen and antibody

The VIDAS HIV DUO Ultra, a fourth-generation immunoassay under development for the simultaneous detection of human immunodeficiency virus type 1 (HIV-1) p24 antigen and antibodies to HIV-1 and HIV-2, was evaluated. The enzyme-linked fluorescence immunoassay, performed on the automated VIDAS instrument, is claimed to detect early and established HIV infection. The assay was challenged with a total of 2,847 samples that included 74 members of 10 seroconversion panels, 9 p24 antigen-only-reactive members of a panel of group M clades, 503 consecutively collected samples from individuals seeking care in the University of Maryland Medical System, 1,010 samples from U.S. blood donors, 1,141 samples from patients in a high-incidence population in Trinidad, 83 samples from a clinic for sexually transmitted diseases in the Bahamas, 10 confirmed HIV-1 group O samples, and 16 confirmed HIV-2 samples from the Cote d'Ivoire. Reference tests were U.S. Food and Drug Administration-licensed HIV antibody screening, p24 antigen tests, HIV confirmatory assays, and the Roche Diagnostics Amplicor HIV-1 Monitor. The VIDAS HIV DUO Ultra demonstrated 100% sensitivity and 99.5% specificity overall, with a 99.7% specificity in low-risk individuals. The analytical sensitivity, as assessed by seroconversion panels and p24 antigen in samples, was equivalent to the sensitivity of the reference assays used to characterize these panels. The VIDAS HIV DUO Ultra is accurate, offers potential advantages over conventional HIV testing for time and cost savings, has walk-away capability, and correctly identifies both early and established HIV infections.

Upper-airway collapsibility: measurements and sleep effects

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is characterized by repetitive pharyngeal collapse during sleep. Several techniques have been proposed to assess the collapsibility of the upper airway in awake humans, but sleep-wake comparisons have rarely been attempted and there are few studies comparing OSA patients to control subjects. We sought to compare two collapsibility measurement techniques between normal and apneic subjects, and between wakefulness and sleep.

DESIGN

We conducted three studies. First, we examined whether collapsibility assessed by negative pressure pulses (NPPs) during wakefulness reflected values during sleep in 21 normal subjects. Second, we determined in these normal subjects whether collapsibility during sleep assessed by NPPs was predictive of collapsibility measured by inspiratory resistive loading (IRL). Finally, we compared upper-airway collapsibility between apnea patients (n = 22) and normal volunteers (n = 38) during wakefulness by NPPs.

SETTING

Clinical and research laboratories at the Brigham and Women's Hospital.

PARTICIPANTS

Two populations of normal subjects (n = 21 and n = 38) and OSA patients (n = 22).

MEASUREMENTS AND RESULTS

Collapsibility during wakefulness, as measured by NPPs, correlated significantly with collapsibility during sleep (r = 0.62; p = 0.003). There was also a significant correlation between the two measures of collapsibility (IRL and NPP) during sleep (r = 0.53; p = 0.04). Both measures revealed a significant increase in pharyngeal collapsibility during sleep as compared to wakefulness. Finally, apnea patients had significantly greater pharyngeal collapsibility than control subjects during wakefulness (p = 0.017).

CONCLUSIONS

These data suggest that upper-airway collapsibility measured during wakefulness does provide useful physiologic information about pharyngeal mechanics during sleep and demonstrates clear differences between individuals with and without sleep apnea.

Use of Exu-Dry in the management of a variety of exuding wounds

Exu-Dry is a relatively new product that is designed to manage a variety of exuding wounds. It is a one-piece, multilayer, highly absorbent, non-adherent wound dressing. It is unique in construction, and incorporates a non-adherent wound contact layer which, it is suggested, makes dressing changes less painful and traumatic. This article explores the use of Exu-Dry in wounds, including heavily exuding wounds, burns, pressure ulcers, skin grafts, donor sites and fungating wounds.

Potential dermal and inhalation exposure to chlorpyrifos in Australian pesticide workers

Chlorpyrifos inhalation, dermal exposure and working practices of 28 pesticide applicators in Western Australia were assessed during a series of single property applications of a 0.5% (n=2) or 1% (n=26) concentration of active ingredient in water solution. Deposition on new cotton gloves worn beneath applicators' usual protective gloves was 2.4 (range 0.12-86.1) mg h(-1). Median deposition of chlorpyrifos onto a new cotton overall worn over other clothing (24 sections removed, corrected for body proportions) was 11.1 (range 0.2-41.9) mg h(-1). Deposition onto seven patches taped to the applicators' skin was 0.04 (range 0.01-4.7) mg h(-1). Inhalation concentration was 5.7 (range 0.7-219) microg m(-3) time weighted average. In one group of 17 applicators' applying to existing properties, breathing zone air concentration correlated (P<0.05) with ambient air temperature (15-38 degrees C). The questionnaire results (29 respondents) indicated applicators' practices led to increased exposure, in particular concerning poor usage and condition of protective equipment and a high frequency of splashes and spills onto the body. Prevention of deposition on clothing, in particular on the lower body is suggested, as well as improved working practices.

Complications Common to Ventricular Assist Device Support Are Rare with 90 Days of DeBakey VAD® Support in Calves

The DeBakey VAD is a miniaturized, electromagnetically driven axial flow pump intended for long-term ventricular assist. Safety and performance data from six calves implanted with the complete DeBakey VAD system are reported elsewhere; here we describe complications and necropsy findings for these same six animals, all of which survived 90 days. The study was conducted according to a uniform protocol, which included anticoagulation and antibiotic prophylaxis. Clinical complications tracked included bleeding, cardiovascular abnormalities (e.g., arrhythmias, tachycardia unrelated to pain, bradycardia), hemolysis, hepatic dysfunction, renal dysfunction, thromboembolism (neurologic or peripheral), or infection. Each adverse event was retrospectively categorized with regard to severity (mild, moderate, severe) and relationship to device. Clinical findings were confirmed by necropsy. There was no evidence of systemic infection, thromboembolism, hemolysis, or renal or hepatic dysfunction in these six animals during the study period. A single adverse event was noted in each of two of the calves. Both events were considered mild according to the predefined criteria. Bleeding related to the surgical implantation procedure and requiring reoperation occurred in one animal. The other animal had evidence of a superficial infection at the exit site of the cables on the left lateral thoracic wall; the infection did not extend into the thoracic cavity. Chronic, healed small renal infarct scars were present in several animals. Mild valvular endocardiosis was observed in two calves and mild fibroelastosis was present in the endocardium at the site of the inflow cannula in three calves; however, these lesions were not considered clinically significant. No other gross or histologic abnormalities were noted at necropsy. In conclusion, calves implanted with the complete DeBakey VAD for 90 days demonstrated few complications and had no significant necropsy findings. Complications common to ventricular assist device (VAD) support (i.e., hemolysis, infection, bleeding, thromboembolism) were rare during long-term support (90 days) with the DeBakey VAD.

Isolation of bovine viral diarrhea virus from a free-ranging mule deer in Wyoming

A noncytopathic type 1a bovine viral diarrhea virus (BVDV) was isolated from a free-ranging yearling female mule deer (Odocoileus hemionus) from northwestern Wyoming (USA). The mule deer was emaciated, weak, and salivating, and Arcanobacterium pyogenes was cultured from lung abscesses. Bovine viral diarrhea virus was isolated from lung, however, BVDV antigen was not detected by immunohistochemistry. The BVDV genotype was determined by reverse transcriptase polymerase chain reaction and the RNA sequences from the 5'UTR and E2 genes compared with sequences of a type 1a BVDV isolated from cattle from the same area as the deer. The sequences from the deer BVDV were distinct from those of the bovine type 1a BVDV, but similar to other bovine type 1a BVDVs. Seventy-four (60%) of 124 sera collected from mule deer in this area had serum neutralizing antibody titers to type 1a BVDV of > or = 1:32. The high prevalence of seropositive mule deer and isolation of BVDV suggests that this virus circulates in the mule deer population. The isolate described in this report is the second reported BVDV isolate from free-ranging deer in North America and the first from a mule deer.

Facial affect and affective prosody recognition in first-episode schizophrenia

Individuals with schizophrenia experience problems in the perception of emotional material; however, the specificity, extent, and nature of the deficits are unclear. Facial affect and affective prosody recognition were examined in representative samples of individuals with first-episode psychosis, assessed as outpatients during the early recovery phase of illness, and non-patients. Perception tasks were selected to allow examination of emotion category results across face and voice modalities. Facial tasks were computerised modifications of the Feinberg et al. procedure (Feinberg, T.E., Rifkin, A., Schaffer, C., Walker, E., 1986. Arch. Gen. Psychiatry 43, 276--279). Prosody tasks were developed using four professional actors, and item selections were based on responses of undergraduates. Participant groups did not differ in their understanding of the words used to describe emotions. Findings supported small but consistent deficits in recognition of fear and sadness across both communication channels for the combined schizophrenia (n=29) and other psychotic disorders (n=28) groups as compared to the affective psychoses (n=23) and non-patients (n=24). A diagnostic effect was evident that was independent of the contribution of intelligence. The detection of emotion recognition impairments in first-episode schizophrenia suggests a trait deficit. The pattern of results is consistent with amygdala dysfunction in schizophrenia and related psychoses.

Seeking a simple measure of analgesia for mega-trials: is a single global assessment good enough?

We sought to investigate the potential of using a simple global estimation ('How effective do you think the treatment was?') as a measure of efficacy by comparing it with at least 50%maxTOTPAR (at least 50% of the maximum possible pain relief) in acute pain studies. One hundred and fifty randomized, double-blind trials included in 11 systematic reviews of single dose, oral analgesics for postoperative pain were used as a source of data. The relationship between the proportion of patients reporting the top two or three values on a five-point global scale and the proportion with at least 50%maxTOTPAR was investigated. Twenty-six trials provided data on the proportion reporting the top two categories (very good or excellent) and 27 gave data on the top three categories (good, very good or excellent). The relationship between the percentage of patients recording the top two categories on a five-point global scale and the proportion with at least 50%maxTOTPAR was fair (r(2)=0.67). That for the top three categories was less good (r(2)=0.57). Similar numbers-needed-to-treat were calculated for aspirin 600/650 mg and ibuprofen 400 mg using at least 50%maxTOTPAR and the top two categories. No real difference was seen in the correlation for standard wording compared to non-standard wording. Individual patient data were also used from four randomized, placebo-controlled, double-blind trials in postoperative pain. The frequency distribution for %maxTOTPAR was plotted for patients reporting each of the five categories on the global scale. A global assessment provides similar measures of analgesic efficacy as TOTPAR derived from hourly measurements, but the effects of adverse effects have yet to be understood.

Cognitively oriented psychotherapy for early psychosis (COPE): a 1-year follow-up

OBJECTIVES

Cognitively oriented psychotherapy for early psychosis (COPE) is aimed at facilitating the adjustment of the person, and at preventing or alleviating secondary morbidity in the wake of the first psychotic episode.

DESIGN

A total of 80 people participated in the initial trial and completed assessments on a range of outcome measures. Post-treatment assessment results from a non-randomized controlled trial of COPE have been previously reported. The present paper describes the results obtained from 51 patients who attended a follow-up assessment 1 year subsequent to the end-of-treatment assessment.

METHOD

The 51 patients formed three groups: (1) those who were offered and accepted COPE; (2) those who were offered COPE but refused it, and continued to receive other services from the Early Psychosis Prevention and Intervention Centre (EPPIC) (refusal subjects); and (3) those who were offered neither COPE nor any other continuing treatment from EPPIC (control subjects).

RESULTS

At 1-year follow-up, there was only one significant difference and this was between the COPE and refusal groups on the Integration/Sealing Over (I/SO) measure (p = .008). End-of-treatment differences were mostly sustained over the 1-year follow-up period. When the complete sample of 80 was considered, there were no differences between the three groups in terms of hospital admissions, community episodes, or time taken to first in-patient re-admission.

CONCLUSIONS

The study was weakened by the poor follow-up rates in the two control groups. This reduced power to detect differences between groups on the seven major measures. However, the relapse data gathered on the complete set of 80 patients were discouraging and suggest that the present formulation of COPE does not confer any advantage to those patients receiving the therapy over those not receiving the therapy.

The experience of patients with rheumatoid arthritis admitted to hospital

OBJECTIVE

To describe the experiences of patients with rheumatoid arthritis (RA) when admitted to hospital.

METHODS

A selected sample of 9 women with RA of at least 3 years duration, who had experienced at least 5 days of inpatient care within the previous 2 years, underwent unstructured interviews in this qualitative, phenomenological study. Information from the interviews was analyzed using Colaizzi's 6 procedural steps.

RESULTS

Five major themes emerged from the study: uncertainty during the first admission to hospital; the process of becoming an experienced patient on subsequent admissions; the evident experience and knowledge of staff; the effect, both positive and negative, of other patients; and the loss of privacy.

CONCLUSION

These findings throw important new light on the experience of patients with RA receiving inpatient rheumatologic care and have the potential to significantly advance nursing practice within rheumatology.

Ovarian cancer models : technical review

Perhaps the most fundamental question that faces the laboratory scientist is, "Which model system should I use to investigate the problem?" Failure to adequately address this issue can compromise even the most meticulous and inspired research program. If this is such a thorny issue, why use model systems at all? As with most biological systems, ovarian cancer is a complex disorder comprising tumor cells, stromal tissues, neovascularization, inflammatory responses, and other host responses to the tumor. Experimental science best progresses by controling all but a single variable and observing what occurs when that variable is modulated. Almost by definition, this requires a homogenous group of samples to work with. Using human cancer patients for research, it becomes rapidly apparent that the diverse nature of the tumors and the hosts greatly complicates such an approach, hence the development of various model systems. The problem with model systems is simple, they are models-not the true disease states, by their very nature they are less than perfect reflections of the way in which the system under investigation performs in vivo in the normal host. Model systems are essential research tools, but have to be used appropriately.

Medical education with the Internet: a pilot training programme in reproductive medicine

Following a detailed information technology survey in the South West Deanery, an Internet educational programme in reproductive medicine was constructed, delivered and assessed. The course followed a problem-based approach using case studies, using an education website and electronic mail (e-mail) to communicate between trainees and trainers. Independent evaluation revealed a high level of satisfaction for both trainees and trainers with an increase in trainees' confidence to deal with patients following the course. This study suggests that the Internet may be used effectively to deliver postgraduate medical education, if the training programme is designed appropriately to computer infrastructure and the computer literacy of the users.

Phosphotyrosine Kinase Assays as a Prescreen for Inhibitors of EGFr

The epidermal growth factor receptor (EGFr) is a 170-kDa glycosylated transmembrane protein found in a wide variety of tissues (1). It is the receptor for epidermal growth factor (EGF), transforming growth factor α (TGFα), and other related growth factor peptides (2,3). In 1980, EGF binding activity of receptor preparations was shown to be associated with a protein kinase activity. Subsequent studies demonstrated that the EGF binding activity and kinase activity were properties of the same protein (4). In the absence of EGF, tyrosine kinase activity is low. Binding of EGF to the receptor domain results in receptor dimerisation and subsequent autophosphorylation of the cytoplasmic domain of EGFr at specific tyrosine residues. This autophosphorylation results in an activation of the tyrosine kinase activity of the EGFr. The phosphorylated tyrosine residues of the EGFr are involved in binding enzymes containing SH2 or SH3 domains (5). Enzymes identified to date that bind tightly to EGFr phosphotyrosine residues include phosphatidyl inositol 3 kinase, phospholipase Cγ and ras GTPase activating protein (6). Binding of these enzymes occurs at highly specific phosphotyrosine residues of the receptor and is believed to be a mechanism for signal transduction from the receptor to the final intracellular target.

vimA gene downstream of recA is involved in virulence modulation in Porphyromonas gingivalis W83

A 0.9-kb open reading frame encoding a unique 32-kDa protein was identified downstream of the recA gene of Porphyromonas gingivalis. Reverse transcription-PCR and Northern blot analysis showed that both the recA gene and this open reading frame are part of the same transcriptional unit. This cloned fragment was insertionally inactivated using the ermF-ermAM antibiotic resistance cassette to create a defective mutant by allelic exchange. When plated on Brucella blood agar, the mutant strain, designated P. gingivalis FLL92, was non-black pigmented and showed significant reduction in beta-hemolysis compared with the parent strain, P. gingivalis W83. Arginine- and lysine-specific cysteine protease activities, which were mostly soluble, were approximately 90% lower than that of the parent strain. Expression of the rgpA, rgpB, and kgp protease genes was the same in P. gingivalis FLL92 as in the wild-type strain. In contrast to the parent strain, P. gingivalis FLL92 showed increased autoaggregration in addition to a significant reduction in hemagglutinating and hemolysin activities. In in vivo experiments using a mouse model, P. gingivalis FLL92 was dramatically less virulent than the parent strain. A molecular survey of this mutant and the parent strain using all known P. gingivalis insertion sequence elements as probes suggested that no intragenomic changes due to the movement of these elements have occurred in P. gingivalis FLL92. Taken together, these results suggest that the recA downstream gene, designated vimA (virulence-modulating gene), plays an important role in virulence modulation in P. gingivalis W83, possibly representing a novel posttranscriptional or translational regulation of virulence factors in P. gingivalis.

Feeding back surveillance data to prevent hospital-acquired infections

We describe the Centers for Disease Control and Prevention's National Nosocomial Infections Surveillance system. Elements of the system critical for successful reduction of nosocomial infection rates include voluntary participation and confidentiality; standard definitions and protocols; identification of populations at high risk; site-specific, risk- adjusted infection rates comparable across institutions; adequate numbers of trained infection control professionals; dissemination of data to health-care providers; and a link between monitored rates and prevention efforts.