Search

Sequential paired samples of blood and seminal fluid were obtained from a cohort of 54 HIV-1-infected homosexual males. The prevalence of GBV-C/HGV RNA in the cell-free fractions of some of these patients was determined using reverse-transcription polymerase chain reaction (RT-PCR). To assess the effects of HIV-1 and HCV infection upon GBV-C/HGV RNA status, blood CD4 cell counts, HCV RNA status, and HIV-1 proviral DNA and viral RNA titres were also determined. GBV-C/HGV RNA was detected in 8/30 (27%) of the blood plasma samples obtained at the start of the study, and was present at a frequency of 14/64 (22%) in all the blood plasma samples tested. By contrast, GBV-C/HGV RNA was not detected in the 26 seminal fluid samples obtained at the start of the study, including 8 samples obtained from patients for which GBV-C/HGV RNA was detected in the corresponding blood sample. Of the samples tested for the presence of both GBV-C/HGV and HCV RNA, there was no evidence of coinfection. Although GBV-C/HGV RNA detection rates were significantly higher in individuals with blood CD4 cell counts greater than 200 cells per microlitre, there were no significant differences in the median blood CD4 cell counts or HIV-1 proviral DNA or viral RNA titres observed between the GBV-C/HGV-positive and -negative individuals. The failure to detect GBV-C/HGV RNA in seminal fluid samples obtained from this cohort would suggest that further studies need to be carried out to determine the roles of sexual transmission and of seminal fluid in GBV-C/HGV infection.

This article describes the biology of antiviral drug resistance with regard to herpes viruses, hepatitis B virus, and HIV. The emergence of antiviral drug resistance is testimony to the potency of current antiviral drugs. Natural selection of such viral variants occurs, such that the strains that are 'fittest' in the presence of the drug persist. Phenotypic and genotypic assays are now available to test clinical viral isolates for resistance. At present, the clearest indication for such testing is in aciclovir-resistant herpes simplex infection. It is important that other resistance assays are subject to studies of clinical utility before their widespread use.

It is accepted that blacks differ from white and Indian hypertensives in their response to hypotensive agents. Black hypertensives in the USA have lower urinary tissue kallikrein (TK) excretion levels than white hypertensives. It has been suggested that blacks respond better to thiazide diuretics than to beta-blockers because thiazides increase TK excretion whereas beta-blockers decrease it. This study compares the excretion of urinary TK in black and Indian hypertensive and normotensive subjects. Urinary TK levels were measured with the selective, synthetic peptic substrate with the sequence of H-D-Val-Leu-Arg-pNA. Ten hypertensive patients on placebo therapy and 10 normotensive black and Indian subjects provided 3 samples at weeks 0, 2 and 4 for the determination of urinary TK. The results were analysed and analysis of variance was used to compare the two racial groups. There were no significant differences in urinary TK values of the three biweekly individual samples. Urinary TK values (ng TK/microgram protein) in Indian hypertensives were generally lower than in black hypertensives.

Hepatitis G virus (HGV) is a newly described virus that has been implicated in transfusion-associated hepatitis. The prevalence of HGV in a group of multitransfused patients with hematological malignancy was studied using a reverse transcription polymerase chain reaction technique. Transfusion histories and serum aspartate aminotransferase (AST) levels were recorded. HGV was detected in 29 of 60 (48%) patients. There was no difference in HGV positivity rates between those with normal AST levels and those with raised AST levels. Analysis of patients by treatment type showed that 20 of 33 (61%) patients who received a bone marrow transplantation procedure were HGV positive compared with 9 of 27 (33%) treated with conventional combination chemotherapy (P = .036) despite similar transfusion histories. There was no significant difference in HGV positivity between patients treated before the introduction of United Kingdom blood donor screening for hepatitis C virus antibody:18 of 39 (46%) and those treated after the introduction of screening 11 of 21 (52%). HGV infection appears to be extremely common in these patients; however, the clinical significance of these findings with respect to liver dysfunction is not yet clear.

Three groups of young male Wistar rats were maintained on diets consisting of 7 mg pyridoxine hydrochloride/kg diet (control and pair-fed groups) and 0 mg pyridoxine hydrochloride/ kg diet (deficient group) for six weeks. The zinc status of all rats was assessed by measuring their erythrocyte zinc-metallothionein-1 (Zn-Mt-1) and plasma zinc levels. A significant difference (p0.001) in plasma zinc levels was observed between the deficient group and the control and pair-fed groups (1.35 micrograms/ml +/- 0.08, 1.99 micrograms/ml +/- 0.06 and 2.03 micrograms/ml +/- 0.07 respectively). Erythrocyte Zn-Mt-1 levels were significantly lower in vitamin B6 deficient rats when compared to control animals. No significant difference in Zn-Mt-1 levels existed between vitamin B6 deficient and pair-fed groups suggesting that the reduced Zn-Mt-1 levels in vitamin B6 deficient rats may be due entirely to their decreased food intake (8.9 g/day compared to 15 g/day of control rats).

Five strains of Xanthomonas albilineans, causal agent of leaf scald disease in sugarcane from various geographical regions, were compared using random amplification of polymorphic DNA (RAPD) to determine whether they could be differentiated at the DNA level. CsCl-purified genomic DNA from these strains were amplified by the polymerase chain reaction (PCR) using arbitrary 10-mer primers according to standard RAPD conditions and the amplification product profiles analysed by conventional agarose gel electrophoresis. Although most RAPD markers were common to all five strains, unique profiles for each strain were discernible using four 10-mer arbitrary primers individually. Reproducible DNA fingerprints indicate that RAPD analysis can be used to identify and differentiate the X. albilineans strains. This technique has the potential for use in monitoring the appearance of foreign strains of X. albilineans in various geographical regions and could be used for the construction of phylogenetic trees.

The relatively unsophisticated approaches at the beginnings of antimicrobial therapy development, although important at the time, have been replaced by ever more complex and ingenious methods as the medical profession and the pharmaceutical industries face up to the realities of the emerging problems of antimicrobial resistance.

ObjectiveThis study aimed to compare self-reported weight and body mass index (BMI) in order to determine discrepancies between subjective and objective obesity-related markers, and possible explanatory factors of overweight and obesity underestimation, in urban, rural and migrant populations.Materials and methodsData from the PERU MIGRANT study, a cross-sectional study, in low-income settings, of urban, migrant (rural-to-urban), and rural groups, including BMI, self-reported weight and socio-demographic indicators were analyzed. Percentage of concurrences between BMI and self-reported weight and Kappa coefficients for inter-rater agreement were calculated. Univariate and standardized descriptive analyses were performed to identify potential explanatory variables for weight underestimation in only overweight and obese individuals, using established BMI and waist circumference cut offs.Results983 Participants-199 urban, 583 migrants and 201 rural-were analyzed. Based on BMI, overall prevalence of obesity was 20.1% (95% CI 17.6%-22.6%), and overweight was 38.3% (95% CI 35.2%-41.2%), with differences between study groups (pDiscussionOverall, high levels of overweight, obesity, and underestimation of BMI status were found, with poor agreement between BMI and self-reported weight, showing the unawareness of weight status severity in this low-income setting.

Background Insufficient PA has been shown to cluster with other CVD risk factors including insufficient fruit and vegetable intake, overweight, increased serum cholesterol concentrations and elevated blood pressure. This paper describes the development of Working on Wellness (WOW), a worksite intervention program incorporating motivational interviewing by wellness specialists, targeting employees at risk. In addition, we describe the evaluation the effectiveness of the intervention among employees at increased risk for cardiovascular disease. Methods The intervention mapping (IM) protocol was used in the planning and design of WOW. Focus group discussions and interviews with employees and managers identified the importance of addressing risk factors for CVD at the worksite. Based on the employees’ preference for individual counselling, and previous evidence of the effectiveness of this approach in the worksite setting, we decided to use motivational interviewing as part of the intervention strategy. Thus, as a cluster-randomised, controlled control trial, employees at increased risk for CVD (N = 928) will be assigned to a control or an intervention group, based on company random allocation. The sessions will include motivational interviewing techniques, comprised of two face-to-face and four telephonic sessions, with the primary aim to increase habitual levels of PA. Measures will take place at baseline, 6 and 12 months. Secondary outcomes include changes in nutritional habits, serum cholesterol and glucose concentrations, blood pressure and BMI. In addition, healthcare expenditure and absenteeism will be measured for the economic evaluation. Analysis of variance will be performed to determine whether there were significant changes in physical activity habits in the intervention and control groups at 6 and 12 months. Discussion The formative work on which this intervention is based suggests that the strategy of targeting employees at increased risk for CVD is preferred. Importantly, this study extends the work of a previous, similar study, Health Under Construction, in a different setting. Finally, this study will allow an economic evaluation of the intervention that will be an important outcome for health care funders, who ultimately will be responsible for implementation of such an intervention. Trial registration United States Clinical Trails Register NCT 01494207

The results of 5018 surveillance cultures for the detection of cytomegalovirus (CMV) from 177 patients undergoing allogeneic T cell-depleted bone marrow transplantation (BMT) were analysed to determine their value in predicting future development of CMV pneumonitis. Twenty-two patients were diagnosed as having CMV pneumonitis. The median times of a positive CMV culture result from urine, saliva or blood before disease in these patients were 32, 8 and 23 days, respectively. The positive predictive value of CMV viraemia for the development of CMV pneumonitis was 0.64. Multivariate analysis showed that recipient pretransplant CMV seropositivity and increasing recipient age were independent risk factors for CMV pneumonitis. By contrast, donor CMV seropositivity was protective against disease, supporting the hypothesis that immunity against CMV can be adopted from donor T cell-depleted marrow. It is concluded that detection of CMV viraemia in a surveillance protocol can predict subsequent CMV pneumonitis but that it is of low sensitivity. This might be improved by more frequent sampling or by the use of a more sensitive assay, such as the polymerase chain reaction, thus identifying individuals who may benefit from 'pre-emptive' therapy.

Renal transplant recipients are at risk of severe morbidity and mortality from CMV disease. We have undertaken routine surveillance for CMV shedding on 133 transplant recipients, using a rapid culture technique, in order to assess the incidence of CMV infection and disease in these patients and to assess the prognostic significance of detection in whole blood, throat swab specimens, or urine. Donor CMV seropositivity was associated with posttransplant CMV infection (P < 0.05) and disease (P = 0.06). CMV infection and disease were associated with the receipt of anti-T-cell antibodies (P < 0.0001 and P = 0.08, respectively). First shedding of virus from any site occurred earlier posttransplant in those recipients who developed disease (median 39 days) than in those who did not (median 55 days)(P < 0.05). Detection of virus in blood occurred at a median time of 16 days before onset of symptoms, compared with 9 days before symptoms in urine, and 3 days after onset of symptoms from throat swab. A positive blood culture represented a relative risk of 7.1 for the subsequent development of disease, compared with 2.1 and 1.8 for positive urine and saliva cultures, respectively. The addition of urine cultures to blood cultures increased the sensitivity for identification of those at risk--however, the relative risk was reduced to 5.8. We conclude that routine surveillance for CMV shedding, especially in blood and urine, can identify recipients at high risk of CMV disease, and propose a trial in which those with asymptomatic viremia are allocated to receive ganciclovir or placebo, in order to assess the efficacy of "preemptive" therapy in this group of patients.

Objective: To determine the prevalence of opportunistic viral infections in multiple tissues at postmortems of HIV-infected patients, and to relate these findings to their antemortem clinical course.Design: A study of viral infections in 16 tissues of HIV-positive postmortem cases, by a combination of histology and cell culture (virus isolation). Clinical details were abstracted retrospectively from patient records.Patients: Forty-seven consecutive autopsies, performed between 1985 and 1992.Setting: Autopsies were conducted by a single pathologist in a single London teaching hospital.Results: Opportunistic viral infections were detected in 72% of all cases, comprising cytomegalovirus (CMV, 66%), herpes simplex virus (11%), JC virus (6%) and adenovirus (2%). The most commonly infected tissues were lung, adrenal, gastrointestinal tract and central nervous system, although all tissue sites sampled could potentially support viral replication. Of 464 tissues tested by both histology and cell culture, histology alone detected CMV in 45 tissues and cell culture alone detected CMV in 31 tissues. We determined that CMV detection in postmortem gastrointestinal tissues and central nervous tissue was significantly associated with antemortem undiagnosed diarrhoea and encephalitis, respectively.Conclusion: There is a high prevalence of opportunistic viral infections in late-stage HIV disease, which is best detected postmortem by the use of both histology and cell culture. Many of these infections correlate with undiagnosed symptoms antemortem. The ability of sensitive methods for virus detection to alert the clinician to such cases antemortem should be critically evaluated, as should attempts to influence the natural history of these infections by antiviral drugs. Continuing clinico-pathological audit is important for AIDS patients in order to monitor the impact of known opportunistic viral infections and to identify others which may emerge as immunosuppression becomes more profound.

The characterization and application of a nested polymerase chain reaction (PCR) assay for the detection of human parvovirus B19 DNA is described. The assay was evaluated with 149 diagnostic serum samples (collected up to 150 days after the onset of symptoms) previously tested by dot blot hybridization for B19 DNA and by class-specific capture radioimmunoassays for the detection of B19 immunoglobulin M (IgM) and IgG. B19 DNA was detectable by the PCR in 70% of the sera. There was a statistically significant association between the detection of B19 DNA by PCR and high B19 IgM values (P < 0.005), low B19 IgG values (P < 0.05), and a short interval between onset of symptoms and serum collection (P < 0.005). Serial serum samples, throat swabs, and peripheral blood mononuclear cells collected from 10 individuals during an outbreak of parvovirus B19 were also tested by the nested PCR. B19 DNA was detectable in the throat swabs at the time of the clinical illness and in the peripheral blood mononuclear cell fraction up to the end point of the study 6 months after infection. The location of the B19 DNA could not be determined in cytocentrifuge preparations of peripheral blood mononuclear cells with nonisotopic in situ hybridization and immunolabelling.

A monoclonal antibody cocktail, directed against immediate early antigens of cytomegalovirus, was assessed in a rapid culture system for detection of CMV (DEAFF) in clinical samples. The antibody cocktail was shown to be equivalent in sensitivity and specificity to our currently used monoclonal antibody. A comparison of DEAFF (using either monoclonal preparation) and conventional cell culture shows that DEAFF detects a smaller proportion of CMV positive samples from those receiving antiviral chemotherapy. The reasons for the discrepancies observed between these techniques are discussed.

The identification of risk factors for viral reactivation following transplantation is essential in order that antiviral prophylactic regimes may be allocated rationally. In the pretransplant period qualitative serological assessment of recipient and donor is informative with regard to the risk of post-transplant reactivation and disease. In addition, the quantitative level of herpes simplex virus (HSV) IgG in the pretransplant recipient is predictive of post-transplant HSV excretion, although this relationship does not exist for other viruses of the herpes group. We discuss the value of surveillance cultures for cytomegalovirus in the post-transplant period in predicting the development of CMV disease, and how this may allow effective intervention to prevent what is a major cause of morbidity and mortality in the transplant population.

Introduction Cytomegalovirus (CMV) infects between 40100% of adults throughout the world, depending primarily on socio-economic status. However, other relevent factors include the degree and form of sexual activity such that, in the UK, homosexual men have a seroprevalence of 80% compared with 42% of sexually active male heterosexuals.' These individuals may present to genitourinary medicine clinics with CMV-related symptoms, most of whom will be infected with HIV. As a member of the herpes group of viruses, infection with CMV leads to a state of latency with the capacity to reactivate at any time. Primary infection in the immunocompetent is usually asymptomatic but may be associated with a mononucleosis-type illness. Reactivation is of major consequence in those who are immunocompromised in whom it may be associated with retinitis, colitis, pneumonitis or encephalitis, all of which carry significant morbidity.2 The availability of effective anti-CMV therapy has heightened the requirement for rapid, sensitive methods of CMV detection, and these will be discussed in detail. By contrast, serological diagnosis of CMV infection (ie antibody determination) depends on a functional immune system and, we believe, plays little role in CMV diagnosis in the immunocompromised individual. Despite the severe symptomatology associated with CMV, it is important to realise that infection does not equate with disease. Thus, virological evidence of CMV infection must always be interpreted within the clinical context before treatment is considered.

Infection with cytomegalovirus is a major cause of morbidity and mortality following orthotopic liver transplantation. In order that preventive strategies may be devised, a detailed assessment of risk factors for infection and disease is required. We have prospectively assessed 46 orthotopic liver transplant recipients for CMV excretion from multiple sites in order to determine incidence of, and risk factors for, CMV infection and disease. Risk factors for posttransplant CMV infection were donor CMV seropositivity, an increased volume of peritransplant whole-blood transfusion and an increased dose of extra steroid therapy to treat rejection episodes. These findings implicate, respectively, transfer of virus with donor organ, transfer of virus with blood transfusion, and stimulation of reactivation of latent virus in recipients through augmented immunosuppression. The possible ways of preventing or ameliorating these effects are discussed.

Parvovirus B19 infection can cause severe complications in pregnant women, individuals with haemolytic anaemia, and those who are immunocompromised. In a hospital outbreak of this infection, a balance should be struck between protection of these individuals and the maintenance of medical services. The index case of an outbreak of parvovirus B19 infection among staff and patients of a paediatric ward was not identified. 58 members of staff were screened for B19 markers and 4 of the 6 susceptible men and 6 of the 24 susceptible women became infected (p = 0·05) as defined by serum IgM and viraemia. 1 of the 11 adults (10 members of staff and 1 parent) infected remained symptom-free. 12 immunocompromised patients were also assessed, and symptom-free infection developed in 2 of these. During the outbreak staff with symptoms were put on sick leave, immunocompromised patients (there were none with haemolytic anaemia) were given normal human immunoglobulin and nursed in single rooms by B19 IgG-positive, IgM-negative staff, and the ward was closed to B19 IgG-negative pregnant women. However, the limitation of spread of infection cannot be attributed with certainty to the measures taken.

The relationship of pre-bone-marrow transplant recipient and donor cytomegalovirus (CMV) antibody level to post-transplant recipient CMV excretion was investigated. CMV excretion was found to be related to pre-transplant recipient serological status, but not to level of antibody. This therefore contrasts with herpes simplex virus (HSV), for which pre-transplant antibody level in recipients predicts post-transplant HSV excretion.

Atenolol is a commonly used beta-blocker that may affect serum thyroid hormone concentrations.' However its influence on the wellrecognized within-subject variation':' of the free levels of thyroxine (free T4), tri-iodothyronine (free T3) and thyroid stimulating hormone (TSH) has not been previously documented. Knowledge of this effect may be important when monitoring thyroid status in relevant patients, Twelve clinically euthyroid men (mean age 53 years, range 37-64; mean wt 80 kg, 61-95), who were receiving 100mg of atenolol daily for stable angina, and a closely matched group (n = 12; mean age 48 years, 35-61; mean wt 79 kg, 59-99) not receiving atenolol were studied. Serum levels of free T4 (Amerlex-M RIA, reference range 8·525·0 pmol/L), free T3 (Amerlex-M RIA, reference range 2·6-8,0 pmol/L) and TSH (Amerlite RIA, reference range 0·3-4'OmU/L) were measured in the cases and controls on four separate occasions (six-month intervals) over an 18-month period; inter-assay CVs 4-6%. None of the patients from either group suffered major illness, received additional medication, or showed a significant change in body weight during the study; serum creatinine remained < 120J1.mol/L. Compliance with atenolol was confirmed by direct questioning and occasional packet counts, The values of FT4, FT3 and TSH were compared between the groups by Student's t-test. Within-subject variance was estimated by analysis of variance and compared between the groups using the F-test;4 this analysis was not factored for analytical variance. The ratio of within-subject variance (including analytical variance) to total variance was also calculated, Although there were no significant differences in the mean levels of the three hormones between the groups, the within-subject variance of FT4 and FT 3 was significantly greater in the atenololtreated patients than in controls (see Table I), With the control group, the ratio of withinsubject variance to total variance for FT4, FT3 and TSH was 25, 45 and 25%, respectively, By contrast, with atenolol treatment the ratio of variances for FT4, FT 3 and TSH increased by a factor of 2,2'1, and 1,8, respectively. However, even after allowing for analytical variance, the within-subject variance for FT3 in this group was higher than that reported by Browning et al? This might have been due to differences in the characteristics of the sample population and to the smaller number of observations made in the present study

The influence of acetoacetate, 3-hydroxybutyrate, and glucose on the assay of urinary creatinine by Jaffe-type and enzymatic methods was studied in vitro. Acetoacetate (greater than or equal to 5 mmol l-1) led to significant overestimation of low concentration urinary creatinine measured by an end-point and a kinetic Jaffe reaction, but neither 3-hydroxybutyrate nor glucose influenced these reactions. None of the metabolites interfered with an enzymatic creatininase assay. It is recommended that, when employing the urinary albumin/creatinine ratio to screen for microalbuminuria in diabetes mellitus, an enzymatic method be used to measure creatinine in Ketostix positive samples, particularly those that are dilute or obtained from patients with a low lean body mass.

Resistance to aciclovir (ACV) among Herpes simplex virus (HSV) isolates is increasingly being reported in the literature particularly in immunocompromised patients. However, there is only limited data available from India despite widespread use of ACV in our hospital. A cross-sectional study was hence conducted to determine the aciclovir (ACV) susceptibility of HSV 1 and 2 isolates using a dye uptake (DU) assay. This study showed a 3.0% prevalence of ACV resistance among HSV-1 strains (2/66, median IC 50 0.098 µg/mL) while in HSV-2 strains, it was 7.8% (5/64, median IC 50 0.195 µg/mL). The IC 50 for the HSV-1 and HSV-2 strains resistant to ACV was greater than or equal to 6.25 µg/mL.

Membranes from the coryneform were prepared by an optimized chemical procedure using EDTA and lysozyme and isolated upon equilibrium sucrose density gradient ultracentrifugation. Four bands, I to IV, of peak densities 1.15, 1.19, 1.21 and 1.245 g. cm−3 respectively, were reproducibly obtained. Immunodiffusion of the isolated membrane bands against bacterial antiserum showed that the immunological integrity of the isolated membranes was retained. Membrane bands I and II had similar precipitin arcs having one major component. A shift towards greater immunological complexity in band IV was observed. Similarly, a change in polypeptide composition established by polyacrylamide gel electrophoresis was found. The major group of polypeptides inband I ranging in size from 39 to 67 kdal were successively reduced in bands II, III and IV whereas the polypeptide of 15.7 kdal and of those in the region of 140 kdal showed respective increases. Transmission electron microscopy revealed similar membrane, structures in all membrane bands with only minor differences between them.

An enzyme-linked immunosorbent assay (ELISA) was developed for the coryneform bacterium isolated from ratoon stunted surgarcane. Parameters governing the ELISA were optimized. These included antibody coating concentration, conjugate concentration and diluent, antigen diluent, the washing procedure, incubation temperature for sample and conjugate, pH and time. The level of detectability of the cultured bacterium by the ELISA was ≥ 1 × 104 Zellen · ml-1.

Offspring of diabetic mothers have been investigated with regard to fetal hepatic and brown adipose tissue lipogenesis in the rat. Results, which cannot be explained by existing theory, are obtained from offspring of subdiabetic mothers and manifest diabetic mothers. In re-evaluating the effect of exogenous insulin on perinatal lipogenesis, we find important differences in hormone sensitivity between liver and brown adipose tissue.

A coryneform bacterium, isolated from ratoon stunted sugarcane, has been obtained in pure culture. Its identification by immunological means was investigated. Optimum conditions for the light microscopic observation of bacterial agglutination by specific antiserum, immunofluorescence and the microcapillary haemagglutination of IgG-sensitized erythrocytes by the bacterium were established. All three assay procedures are simple and rapid. By comparison, more samples can be handled at any one time bythe microcapillary haemagglutination method. Based on bacterial agglutination, the antiserum is specific for the coryneform isolated from ratoon-stunted sugarcane.

Both starvation of and feeding a high linoleic acid content diet to rats during late pregnancy resulted in (relative to stock diet fed controls) a decrease in maternal hepatic glycogen content and lipogenesis, reduced blood glucose levels and an increase in blood ketone levels whereas only fat feeding caused an increase in blood triglyceride levels and only starvation resulted in a decrease in the amount of brown adipose tissue. Maternal starvation resulted in decreased fetal body, liver and brown adipose tissue weights, diminished liver and brown adipose glycogen content and lipogenesis and lowered blood glucose levels. Both maternal fat feeding and starvation caused triglyceride accumulation in fetal liver, elevated blood ketone levels and an increased proportion of fetal liver and carcass fatty acids accounted for by linoleic acid.

Lipopolysaccharides (LPS) were extracted from the type species of the sugarcane leaf scald pathogen Xanthomonas albilineans from Fiji and additional isolates from Australia, Mauritius and South Africa. After resolution by sodium dodecyl sulphate-polyacrylamide gel electrophoresis, the LPS were visualized using a modified silver staining method and analysed by densitometric scanning. Three distinct electrophoretic patterns were identified: the LPS pattern of the Fijian isolate differed from those of the other isolates. Immunological cross-reactivity of the LPS and gamma globulins was assessed by immunoblotting. Immunoblotting showed that although IgG raised against other isolates cross-reacted with the LPS of one another, they did not react with the purified LPS of the Fijian isolate. Differences in LPS patterns and serological cross-reactivity may be due to differences in the length and conformation of the O-polysaccharide chains of the LPS.

Background Europe is seeing more non-B subtype HIV, reflecting patterns of migration. In France in 2003, 19% of new infections were non-B subtype [1] and UK data showed a rise in infection acquired heterosexually in Africa: 19% in 1992, to 33% in 2006 [2]. With the roll-out of antiretrovirals (ART) in the developing world and use of single dose nevirapine for prevention of mother-to-child transmission, reports of emerging transmitted drug resistance (TDR) among non-B subtypes have followed.