Is smoking tobacco an independent risk factor for HIV infection and progression to AIDS? A systemic review

OBJECTIVES

To systematically review the evidence of the relation between smoking tobacco and HIV seroconversion and progression to AIDS.

METHODS

A systematic review was undertaken of studies to look at tobacco smoking as a risk factor for either HIV seroconversion or progression to AIDS.

RESULTS

Six studies were identified with HIV seroconversion as an outcome measure. Five of these indicated that smoking tobacco was an independent risk factor after adjusting for important confounders with adjusted odds ratios ranging from 1.6 to 3.5. 10 studies were identified using progression to AIDS as an end point of which nine found no relation with tobacco smoking.

CONCLUSIONS

Tobacco smoking may be an independent risk factor for HIV infection although residual confounding is another possible explanation. Smoking did not appear to be related to progression to AIDS although this finding may not be true in developing countries or with the longer life expectancies seen with highly active antiretroviral therapy.

Antibiotic resistance of retail food and human Campylobacter isolates on the island of Ireland from 2001-2002

The antimicrobial resistance profiles of Campylobacter isolates recovered from a range of retail food samples (n=374) and humans (n=314) to eight antimicrobial compounds were investigated. High levels of resistance in food C. jejuni isolates were observed for ceftiofur (58%), ampicillin (25%) and nalidixic acid (17%) with lower levels observed for streptomycin (7.9%) and chloramphenicol (8.3%). A total of 80% of human C. jejuni isolates were resistant to ceftiofur, while 17% showed resistance to ampicillin and nalidixic acid, 8.6% to streptomycin and 4.1% to chloramphenicol. Resistance to clinically relevant antimicrobials such as erythromycin, ciprofloxacin and tetracycline was 6.7, 12, and 15% respectively for all food isolates and was similar to corresponding resistance prevalences observed for human isolates, where 6.4, 12 and 13% respectively were found to be resistant. Comparisons of C. jejuni isolates in each location showed a high degree of similarity although some regional variations did exist. Comparison of total C. jejuni and C. coli populations showed minor differences, with C. jejuni isolates more resistant to ampicillin and ceftiofur. Multidrug resistance patterns showed some profiles common to human and clinical isolates.

Environmental survival mechanisms of the foodborne pathogen Campylobacter jejuni

Campylobacter spp. continue to be the greatest cause of bacterial gastrointestinal infections in humans worldwide. They encounter many stresses in the host intestinal tract, on foods and in the environment. However, in common with other enteric bacteria, they have developed survival mechanisms to overcome these stresses. Many of the survival mechanisms used by Campylobacter spp. differ from those used by other bacteria, such as Escherichia coli and Salmonella spp. This review summarizes the mechanisms by which Campylobacter spp. adapt to stress conditions and thereby increase their ability to survive on food and in the environment.

Comparison of a membrane surface adhesion recovery method with an IMS method for use in a polymerase chain reaction method to detect Escherichia coli O157:H7 in minced beef

In this study, enrichment procedures and two recovery methods, a membrane surface adhesion technique and an immunomagnetic separation (IMS), were compared for use in conjunction with a multiplex polymerase chain reaction (PCR) method with a view to describing a fast (24 h) and economical test for detection of Escherichia coli O157:H7 in meat samples. The study showed no significant difference between three different enrichment media (BHI, E. coli (E.C.) broth+novobiocin, modified tryptone soya broth (mTSB)+novobiocin) or two incubation temperatures (37 or 41.5 degrees C) for growth of E. coli O157:H7 in minced beef. Minced beef samples inoculated with E. coli O157:H7 at 40 cfu g(-1) were incubated at 37 degrees C for 16 h in E.C. broth+novobiocin reaching numbers of (log(10)7.82-8.70). E. coli O157:H7 were recovered by attachment to polycarbonate membranes immersed in the enriched cultures for 15 min or by immunomagnetic separation. Subsequent treatment of recovered membranes or IMS beads with lysis buffer and phenol/chloroform/isoamyl alcohol was used to extract the DNA from the extracted E. coli O157:H7 cells. The results show when E. coli O157:H7 was present at high levels in the enriched meat sample (log(10)9.6-7.5 cfu ml(-1); >16-h enrichment), the membrane and IMS techniques recovered similar levels of the pathogen and the microorganism was detectable by PCR using both methods. At lower levels of E. coli O157:H7 (log(10)6.4), only the IMS method could recover the pathogen but at levels below this neither method could recover sufficient numbers of the pathogens to allow detection. The conclusion of the study is that with sufficient enrichment time (16 h) the membrane surface adhesion membrane extraction method used in combination with multiplex PCR has the potential for a rapid and economical detection method.

Occurrence of Campylobacter in retail foods in Ireland

A surveillance study was carried out to determine the prevalence of Campylobacter in a range of retail foods purchased in three Irish cities over a 20-month period between March 2001 and October 2002. In total 2391 food samples were analysed during this period. Campylobacter was isolated from 444 raw chicken (49.9%), 33 turkey (37.5%) and 11 duck samples (45.8%). Lower isolation rates of 7/221 (3.2%), 10/197 (5.1%) and 31/262 (11.8%) were observed for raw beef, pork and lamb, respectively. One sample of pork paté from 120 samples analysed (0.8%) was Campylobacter-positive. A total of three shellfish samples (oysters) from 129 raw specimens examined (2.3%) were found to contain Campylobacter. Low prevalences of the organism (0.9%) were also isolated from fresh mushrooms. Of 62 raw bulk tank milk samples analysed, Campylobacter was recovered in a single sample (1.6%). Campylobacter was not detected in any of the comminuted pork puddings, prepared vegetables and salads, retail sandwiches or cheeses made from unpasteurised milk. In total, 543 Campylobacter were isolated from all of the food samples analysed, of which 453 (83.4%) were confirmed as Campylobacter jejuni and the remaining 90 (16.6%) as Campylobacter coli.

Application of real-time PCR and RT-PCR assays for the detection and quantitation of VT 1 and VT 2 toxin genes in E. coli O157:H7

Real-time PCR assays, based on hybridisation probes and LightCycler technology, were developed for VT 1 and VT 2 genes and applied to the detection and quantitation of DNA and mRNA of Escherichia coli O157:H7. The qualitative consensus PCR assay for the detection of VT 1 and/or VT 2 genes had a detection limit of 100 fg of E. coli O157:H7 genomic DNA and did not detect DNA from 13 non-VTEC isolates. When E. coli O157:H7 was inoculated into minced beef, enriched and recovered by immunomagnetic separation, the real-time consensus PCR assay had a detection limit of log(10)3.5 ml(-1) E. coli O157:H7 cells. Nineteen E. coli O157:H7 isolates, derived from food, bovine samples and human faeces, were analysed and compared for mRNA expression of three genes, VT 1, VT 2 and gapA (housekeeping gene), using quantitative real-time PCR assays. While there was no statistically significant difference for the expression of the VT 1 (p=0.134) or VT 2 (p=0.52) mRNA in the E. coli O157:H7 isolates from food, bovine and human sources, three clinical isolates did show lower expression of VT 2 compared to other isolates in the study. The study indicates that the consensus qualitative real-time PCR assay for VT 1 and VT 2 is rapid and sensitive and that the quantitative assays reported here have the potential to be used as an alternative method to more conventional methods for studying VT 1 and VT 2 virulence gene expression in E. coli O157:H7 with potential application in other pathogenic E. coli species.

Raised intracranial pressure presenting with spontaneous periorbital bruising: two case reports

The venous drainage of the orbit is known to be via the ophthalmic and vortex veins which communicate with the cavernous sinus. We describe two patients with raised intracranial pressure presenting with periorbital bruising. In one patient dural venous sinus thrombosis was demonstrated and it is suspected that the cause of the raised intracranial pressure may have been the same in the second. We suggest that the abrupt rise of pressure in the cerebral venous system was transmitted via the cavernous sinus to the orbital venous system.

The effect of cannabis on tremor in patients with multiple sclerosis

BACKGROUND

Disabling tremor is common in patients with multiple sclerosis (MS). Data from animal model experiments and subjective and small objective studies involving patients suggest that cannabis may be an effective treatment for tremor associated with MS. To our knowledge, there are no published double-blind randomized controlled trials of cannabis as a treatment for tremor in MS patients.

METHODS

The authors conducted a randomized double-blind placebo-controlled crossover trial to examine the effect of oral cannador (cannabis extract) on 14 patients with MS with upper limb tremors. There were eight women and six men, with a mean age of 45 years and mean Expanded Disability Status Scale score of 6.25. Patients were randomly assigned to receive each treatment and the doses escalated over a 2-week period before each assessment. The primary outcome was change on a tremor index, measured using a validated tremor rating scale. The study was powered to detect a functionally significant 50% improvement in the tremor index. Secondary outcomes included accelerometry, an ataxia scale, spiral drawing, finger tapping, and nine-hole pegboard test performance.

RESULTS

Analysis of the data showed no significant improvement in any of the objective measures of upper limb tremor with cannabis extract compared to placebo. Finger tapping was faster on placebo compared to cannabis extract (p < 0.02). However, there was a nonsignificant trend for patients to experience more subjective relief from their tremors while on cannabis extract compared to placebo.

CONCLUSIONS

Cannabis extract does not produce a functionally significant improvement in MS-associated tremor.

Stroke in Devon: knowledge was good, but action was poor

BACKGROUND AND AIM

Effective implementation of early treatment strategies for stroke requires prompt admission to hospital. There are several reasons for delayed admission. Good awareness should facilitate early admission. We identified local targets for education.

METHODS

Four groups, each of 40 people, completed questionnaires to determine their knowledge of stroke symptoms and risk factors, and the action they took or would take in the event of a stroke. The groups were: patients with a diagnosis of stroke or TIA (within 48 hrs of admission); patients at risk of stroke; the general population; and nurses.

RESULTS

Forty per cent of stroke patients identified their stroke. Median time from onset of symptoms to seeking medical help was 30 minutes. Medical help was sought by the patient themselves in only 15% of cases. In 80% of cases the GP was called rather than an ambulance. Of the at risk group, 93% were able to list at least one symptom of acute stroke, as were 88% of the general population. An ambulance would be called by 73% of the at risk group in the event of a stroke. Patients with self reported risk factors for stroke were largely unaware of their increased risk. Only 7.5% of at risk patients acquired their stroke information from the medical profession.

CONCLUSIONS

Public knowledge about stroke is good. However, stroke patients access acute services poorly. At risk patients have limited awareness of their increased risk. A campaign should target people at risk, reinforcing the diagnosis of stroke and access to medical services.

Provision of 24 hour acute neurology care by neurologists: manpower requirements in the UK

OBJECTIVES

The ABN has published standards of care for patients with acute neurological disease. Derriford Hospital provides a 24 hour neurology intake service to a population of 500,000 with the equivalent of four consultants, three specialist registrars (SpRs), and four senior house officers (SHOs) with a 37 bed ward. The authors undertook a prospective study of all neurology admissions to enable calculation of manpower necessary to meet the ABN guidelines.

METHODS

All admissions to the neurology department were analysed prospectively for a three month period (March to May 2002).

RESULTS

There were 629 admissions (equating to 2500 per year); data were collected for 93%. 78% of admissions were emergency, 16% elective. The mean number of neurology inpatients at any time was 76, with three (4%) being elective. The main diagnostic categories were stroke (29%), headache syndrome (13%), and epilepsy or seizures (12%). With regard to emergency admissions, 94% were seen by a neurology SHO within 6 hours and 81% by an SpR or consultant within 24 hours. Twenty five percent of emergency admissions were not seen by a consultant. 55% of patients were cared for on non-neurological wards for their entire admission. Median length of stay for stroke patients was 9.5 days, compared with 4 days for other patients. 37% of patients received a neurology follow up appointment. Currently each SpR spends 18 hours per week involved in the care of acute neurology admissions.

CONCLUSION

Meeting the ABN guidelines will require an increase in total neurology bed provision to at least 15 per 100,000 population, with the equivalent of 3 consultant sessions (11 hours/week). Meeting the European Working Time Directive will require a minimum of 8-10 SpRs working a full shift system, which will have a significant impact on training and other aspects of service delivery.

Identification of a novel stress resistance mechanism in Campylobacter jejuni

AIM

To study stress resistance mechanisms in Campylobacter spp.

METHODS AND RESULTS

Campylobacter strains were grown to the appropriate phase in Brucella broth. The cells were diluted into either cell-free spent medium (obtained by filtration of a grown culture) or a freshly prepared medium and the pH reduced to 4.5, a lethal pH value. At suitable time intervals survivors were enumerated on Campylobacter blood free selective agar base. The cell-free spent medium from mid-exponential and stationary phase had a protective effect on acid and thermal stress in Campylobacter jejuni CI 120, a natural isolate. The protective effect of the extracellular compound was not significantly inactivated by boiling, but was inactivated by proteinase.

CONCLUSIONS

The present study suggests that a protein (or proteins) accumulated by C. jejuni CI 120 during growth may play an active role in the induction of stress responses and that this protein is heat stable.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results indicate that C. jejuni CI 120, a natural isolate, has the ability to use extracellular signalling mechanisms to induce tolerance to stress factors. This is a major advancement in the understanding of the physiological basis for survival of C. jejuni in the environment.

A comparison of two culture media for the recovery of thermophilic campylobacters in broiler farm samples

A study to evaluate the performance of two different brands of media (Oxoid, Basingstoke, UK, and Mast Diagnostics, Merseyside, UK) for the isolation of thermophilic campylobacters from a range of broiler farm samples was undertaken. Oxoid media performed significantly better than the Mast formulations with overall Campylobacter recovery rates of 46% and 30.5%, respectively, observed from 213 samples tested (p< or =0.05). Consistently higher recoveries of campylobacters were observed from all samples when the results using both types of media were combined.

Antimicrobial resistance of Campylobacter jejuni and Campylobacter coli isolates from broiler chickens isolated at an Irish poultry processing plant

AIMS

The antibiotic susceptibility of Campylobacter jejuni and Campylobacter coli isolates from broiler chickens were determined in order to evaluate the level of antibiotic resistance of Campylobacter species in the Irish poultry industry.

METHODS AND RESULTS

Seventy-eight Camp. jejuni and 22 Camp. coli strains were examined for susceptibility to eight antibiotics using the disc diffusion assay. The highest level of resistance of the Camp. jejuni isolates was recorded to ampicillin (35.9%), followed by 20.5% to tetracycline, 20.5% to naladixic acid, 17.9% to ciprofloxacin, 10.2% to erythromycin, 2.5% to streptomycin and 1.2% to kanamycin. Multidrug resistance to two or more antibiotics was seen for 30.7% of Camp. jejuni strains. Resistance of the Camp. coli isolates was shown to ampicillin (9%) and tetracycline (18.2%).

CONCLUSIONS

The majority of Camp. jejuni strains were susceptible to antibiotics commonly used for human therapy. Camp. coli strains showed very low resistance levels and were susceptible to six of the eight antimicrobial agents studied.

SIGNIFICANCE AND IMPACT OF THE STUDY

Levels of Camp. jejuni and Camp. coli antimicrobial resistance in Irish poultry production was assessed to determine the current situation in Ireland. The prevalence of antibiotic resistance of Campylobacter strains isolated from broiler chickens was low.

Disease severity and associated family impact in childhood atopic dermatitis

AIM

To examine the association between childhood atopic dermatitis (AD) severity and family impact at baseline and after an intervention by a physician specialist, using validated measures of both severity and family impact.

METHODS

Cross sectional self administered survey of parent-caregivers of 49 randomly selected children with AD; 35 parents were available for follow up. Family impact was measured using a modified AD Family Impact Scale completed by the parent-caregiver. The child's disease severity was measured using both the investigator's assessment via the Eczema Area and Severity Index (EASI) and the caregiver's assessment via the recently validated Self Assessment Eczema Area and Severity Index (SA-EASI).

RESULTS

The parent-caregiver's assessment of severity of the child was the most significant correlate of the family impact of the child's AD (p = 0.65 at baseline and p = 0.38 at follow up). In multivariate regression models, the parent-caregiver's estimate of severity remained the single strongest predictor of family impact before and after receipt of dermatologist care, as well as the difference in impact between pre and post-dermatologist care.

CONCLUSIONS

There is evidence to support the ability of parent-caregivers of children with AD to accurately determine severity of their child's AD; perceived severity is the driver of the family impact of this condition. Treatment of a child by a physician specialist is associated with reductions in both perceived severity, as well as family impact of this condition.

How do people with Type 2 diabetes perceive and respond to cardiovascular risk?

OBJECTIVES

To explore how people with Type 2 diabetes perceive cardiovascular risk, and how those perceptions might affect their motivation to make lifestyle changes.

METHODS

The setting was a diabetes clinic in a UK teaching hospital. A qualitative study was conducted, using semistructured individual interviews and template analysis of content. The participants were 20 Type 2 diabetic patients, aged between 52 and 77 years, half with and half without cardiovascular disease (CVD).

RESULTS

Whether they had CVD or not, most people were aware they were at risk of it, of its causative factors, and possible effects. However, they were more likely to attribute it to unchangeable factors like 'stress' and 'heredity', than medical risk factors like cholesterol and smoking. Patients with pre-existing CVD correctly regarded their risk as higher than those without. Few saw any direct link between being diabetic per se and cardiovascular risk. Lifestyle changes were precipitated by major life events and motivated by family support, fear of complications, and a belief that one should follow doctors' advice. A common reaction to CVD and diabetes was stoical acceptance, allowing patients to view their lives positively, whilst living with unpredictable potentially disabling diseases.

CONCLUSIONS

Patients were unaware how strongly diabetes influences cardiovascular risk. Their ideas about risk were very different from those of conventional medicine, and provided individual rationales for making choices about treatment and risk-influencing behaviour. Contextual factors, such as family milieu, also influenced their behaviour. Clinicians should not assume patients share the same mental model of risk as they, and must be prepared to explore peoples' individual constructs and health beliefs.

Neighbourhood catchments: a new approach for achieving ownership and change in catchment and stream management

The Neighbourhood Catchment approach integrates land and stream management practices at a property and through to a local catchment scale, links production and environmental goals, and is a building block to achieve ownership and change at a sub-catchment scale and larger. Research conducted in two 'focus' Neighbourhood Catchments has shown that land management practices that retain >30% soil cover reduce sediment movement to streams. The Neighbourhood Catchment approach engages both early and cautious adopters, and enables continuous improvement of resource management to take place, and be recorded at an individual property and local catchment scale.

Cellular determinants of the mutational specificity of 1-nitroso-6-nitropyrene and 1-nitroso-8-nitropyrene in the lacI gene of Escherichia coli

We have characterized 202 lacI(-) mutations, and 158 dominant lacI(-d) mutations following treatment of Escherichia coli strains NR6112 and EE125 with 1-nitroso-6-nitropyrene (1,6-NONP), an activated metabolite of the carcinogen 1,6-dinitropyrene. In all, 91% of the induced point mutations occurred at G:C residues. The -(G:C) frameshifts were the dominant mutational class in the lacI(-) collections of both NR6112 and EE125, and in the lacI(-d) collection of NR6112. Frameshift mutations occurred preferentially in runs of guanine residues, and their frequency increased with the length of the reiterated sequence. In strain EE125, which contained the plasmid pKM101, there was a marked stimulation in the frequency of base substitution mutations that was particularly apparent in the lacI(-d) collection. This study completes a comprehensive analysis of 1194 lacI(-) and 348 lacI(-d) mutations induced by either 1,6-NONP or its positional isomer 1-nitroso-8-nitropyrene (1,8-NONP) in strains of E. coli that differ with regard to their ability to carry out nucleotide excision repair and/or their ability to express the translesion synthesis DNA polymerase RI (MucAB) encoded by plasmid pKM101. Among the mutations are 763 frameshift mutations, 367 base substitutions and 47 deletions; these mutations have been characterized at more than 300 distinct sites in the lacI gene. Our studies provide detailed insight into the DNA sequence alterations and mutational mechanisms associated with dinitropyrene mutagenesis. We review the mutational spectra, and discuss cellular lesion repair or tolerance mechanisms that modulate the observed mutational specificity.

Organ procurement 1999-2000: how is Hawaii doing?

With the advent of The Final Rule, the state of Hawaii should have potential organ donor identification and referral rates of 100%. However, a retrospective chart review of 4,697 deaths in 1999 and 4,730 deaths in 2000, revealed identification rates of 80% and 84%, and referral rates of 53% and 71%, respectively. Proper recognition and referral of all potential donors is essential to bridging the enormous gap between the supply of organs and its demand.

Resistance training improves single muscle fiber contractile function in older women

The purpose of this study was to 1) examine single cell contractile mechanics of skeletal muscle before and after 12 wk of progressive resistance training (PRT) in older women (n = 7; 74 +/- 2 yr) and 2) to compare these results to our previously completed single cell PRT work with older men (n = 7; 74 +/- 2 yr) (Trappe S, Williamson D, Godard M, Porter D, Rowden G, and Costill D. J Applied Physiol 89:143--152, 2000). Knee extensor PRT was performed 3 days/wk at 80% of one-repetition maximum. Muscle biopsies were obtained from the vastus lateralis before and after the PRT. Chemically skinned single muscle fibers (n = 313) were studied at 15 degrees C for peak tension (P(o)), unloaded shortening velocity (V(o)), and power. Due to the low number of hybrid fibers identified post-PRT, direct comparisons were limited to MHC I and IIa fibers. Muscle fiber diameter increased 24% (90 +/- 2 to 112 +/- 6 microm; P < 0.05) in MHC I fibers with no change in MHC IIa fibers. P(o) increased (P < 0.05) 33% in MHC I (0.76 +/- 0.04 to 1.01 +/- 0.09 mN) and 14% in MHC IIa (0.73 +/- 0.04 to 0.83 +/- 0.05 mN) fibers. Muscle fiber V(o) was unaltered in both fiber types with PRT. MHC I and IIa fiber power increased (P < 0.05) 50% [11 +/- 2 to 17 +/- 2 microN. fiber length (FL). s(-1)] and 25% (40 +/- 8 to 51 +/- 6 microN. FL. s(-1)), respectively. However, when peak power was normalized to cell size, no pre- to postimprovements were observed. These data indicate that PRT in elderly women increases muscle cell size, strength, and peak power in both slow and fast muscle fibers, which was similar to the older men. However, in contrast to the older men, no change in fiber V(o) or normalized power was observed in the older women. These data suggest that older men and women respond differently at the muscle cell level to the same resistance-training stimulus.

Role of the sternocleidomastoid muscle flap preventing Frey's syndrome and maintaining facial contour following superficial parotidectomy

The sternocleidomastoid muscle flap may play a significant role in reducing the incidence of Frey's syndrome and maintaining facial contour after parotidectomy. Patients who underwent superficial parotidectomy from August 1992 to March 1999 were divided into two groups (N = 26). One group had sternocleidomastoid muscle flap reconstruction. A historical cohort study was designed with the two groups being matched for sex, age, pathology, postoperative radiation, date of surgery, and extent of dissection. The starch iodine test was used to evaluate for gustatory sweating, and the Observer Rated Disfigurement Scale was used to assess facial contour and aesthetics. The results of our study suggest that the sternocleidomastoid flap reconstruction following parotidectomy surgery does not alter the incidence of Frey's syndrome and does not significantly improve facial contour and aesthetics.