Ultrasonic plaque character and outcome after lower limb angioplasty.

Purpose: The value of ultrasonic plaque characteristics in identifying patients at "high-risk" of restenosis after percutaneous transluminal angioplasty (PTA) was studied.

Methods: Thirty-one arterial stenoses (6 common iliac, 2 external iliac, 1 profunda femoris, 21 superficial femoral, and 1 popliteal) in 17 patients who underwent angioplasty were studied by means of duplex scanning. With a computer-based program, B-mode images were digitized and normalized using 2 reference points, blood and adventitia.

Comparison of the antibody repertoire generated in healthy volunteers following immunization with a monomeric recombinant gp120 construct derived from a CCR5/CXCR4-using human immunodeficiency virus type 1 isolate with sera from naturally infected individuals.

We have characterized sera from healthy volunteers immunized with a monomeric recombinant gp120 (rgp120) derived from a CCR5/CXCR4 (R5X4)-using subtype B isolate of human immunodeficiency virus type (HIV-1), HIV-1W61D, in comparison to sera from long-term HIV-1-infected individuals, using homologous reagents. Sera from vaccinees and HIV-1 positive subjects had similar binding titers to native monomeric rgp120W61D and showed a similar titer of antibodies inhibiting the binding of soluble CD4 (sCD4) to rgp120W61D. However, extensive peptide binding studies showed that the overall pattern of recognition of vaccinee and HIV-1-positive sera is different, with vaccinee sera displaying a wider and more potent recognition of linear V1/V2 and V3 domain epitopes.

Interindividual variability in P450-dependent generation of neoantigens in halothane hepatitis.

Halothane hepatitis occurs because susceptible patients mount immune responses to trifluoroacetylated protein antigens, formed following cytochrome P450-mediated bioactivation of halothane to trifluoroacetyl chloride. In the present study, an in vitro approach has been used to investigate the cytochrome P450 isozyme(s) which catalyze neoantigen formation and to explore the protective role of non-protein thiols (cysteine and reduced glutathione). Significant levels of trifluoroacetyl protein antigens were generated when human liver microsomes, and also microsomes from livers of rats pre-treated with isoniazid, phenobarbital or beta-naphtoflavone, were incubated with halothane plus a nicotinamide adenine dinucleotidephosphate (NADPH) generating system.

Detection of genital mycoplasmas by PCR.

Mycoplasmas are the smallest prokaryotes capable of self-replication. They belong to the class Mollicutes (meaning soft-skin) and have evolved regressively, by genome reduction, from Gram-positive bacterial ancestors, namely certain clostridia (1). The taxonomy of the class Mollicutes containing four orders, five families, and eight genera, is shown in Table 1 (2).

Sexual histories, partnerships and networks associated with the transmission of gonorrhoea.

We aimed to describe and compare sexual links among people with gonorrhoea, by studying patients in 2 UK departments of genitourinary medicine. Interviews were completed for 510 and 235 cases in London and Sheffield respectively. There was a greater proportion of cases in men, homosexual men, non-white and non-British people and fewer female sex workers in London.

Porphyrins in urine, plasma, erythrocytes, bile and faeces in a case of congenital erythropoietic porphyria (Gunther's disease) treated with blood transfusion and iron chelation: lack of benefit from oral charcoal.

Congenital erythropoietic porphyria is a rare genetic disorder in which deficiency of uroporphyrinogen III synthase results in excessive production of Type I porphyrins. The main clinical features are severe photodestruction of the skin and haemolytic anaemia. Treatment consists of shielding from light, blood transfusions and splenectomy, but is generally unsatisfactory.

Chlamydia pneumoniae in vascular tissue.

This review summarizes the evidence for the presence of Chlamydia pneumoniae organisms in atherosclerotic lesions. A total of 17 publications are mentioned concerning this topic. In all but two, both from the same group, evidence is presented by means of various techniques for the existence of the organisms in atherosclerotic tissue.

The in-vitro generation of dendritic cells from blast cells in acute leukaemia.

Dendritic cells (DC) are potent antigen-presenting cells responsible for the initiation of primary antigen-specific immune responses. In chronic myeloid leukaemia DC have been generated from Ph+ cells and these Ph+ DC are capable of stimulating cytolytic T-cell responses against the parent leukaemia cells. The prevalence of this phenomenon in acute leukaemia (AL) is unknown and we have therefore studied a variety of acute leukaemias to determine their potential for DC development.

Other methods of laparoendoscopic hernia repair: mini-hernia--inguinal hernia repair through a 2-cm incision.

Mini-hernia repair is an endoscopic modification of the Lichtenstein tension-free repair. Clinical trials are warranted to determine the efficacy of this procedure and any advantages it may have over the original operation.

Cell cycle arrest following exposure of EBV-immortalised B-cells to gamma irradiation correlates with inhibition of cdk2 activity.

The exposure of Epstein-Barr virus immortalised B cells (LCLs) to the genotoxic effects of gamma irradiation causes a decreased proliferation of the cells. The early events in this process have been investigated here. The induction of p53 expression correlates with a cell cycle arrest in the G1 and G2/M phases of the cell cycle within 24 h of exposure.

Characterization of sera from subjects infected with HIV-1 subtypes B and E in Thailand by antibody binding and neutralization.

The range and specificity of the humoral immune response to HIV-1 subtypes B and E was investigated in Thai samples. Sera from HIV-1-positive subjects, consisting of subtypes B (n = 24) and E (n = 138), were characterized in relation to the neutralization of primary isolates and T-cell line-adapted (TCLA) strains and binding to monomeric gp120, the CD4/gp120 binding site (BS), and V3 peptides. A subtype-specific pattern of antibody binding was observed with the exception of the CD4/gp 120MN BS.

Molecular screening of sheep for bovine spongiform encephalopathy.

Bovine spongiform encephalopathy (BSE) may have transmitted to sheep through feed and pose a risk to human health. Sheep BSE cannot be clinically distinguished from scrapie, and conventional strain typing would be impractical on a significant scale. As human prion strains can be distinguished by differences in prion protein (PrPsc) conformation and glycosylation we have applied PrP(Sc) typing to sheep.

Variation amongst human isolates of Brachyspira (Serpulina) pilosicoli based on biochemical characterization and 16S rRNA gene sequencing.

Brachyspira pilosicoli (formerly Serpulina pilosicoli) causes swine spirochaetosis and can also be isolated fro human faeces, although its role in human disease remains unclear. The genetic and biochemical variations amongst 19 isolates of human spirochaetes from five different countries were evaluated and compared to those found amongst swine isolates of B. pilosicoli.

Regulation of epidermal growth factor receptor by androgens in human endometrial cells in culture.

Women with polycystic ovaries (PCO) have a thicker endometrium than women with normal ovaries. This cannot be due to unopposed oestrogen, as it occurs in ovulatory cycles. Androgens may be involved, as these are raised in women with PCO.

Avoidable deficiencies in the delivery of health care to children with meningococcal disease.

Objectives: It is apparent that delays and inadequate or inappropriate management occur frequently and may contribute to the continued high mortality seen in meningococcal disease. An attempt has been made to define the major sources of delay or inappropriate treatment.

Methods: A prospective, descriptive study of children with meningococcal disease referred to a tertiary centre paediatric intensive care and infectious disease unit.

The pharmacokinetics of saquinavir: a Markov chain Monte Carlo population analysis.

Saquinavir is an HIV proteinase inhibitor marketed as a treatment for HIV infection. The drug has potent (Ki approximately 0.1 nM) antiviral activity and acts by inhibiting the processing of gag and gag-pol polyproteins, thus blocking the maturation of replicated viral particles.

Plasma antioxidants: evidence for a protective role against reactive oxygen species following cardiac surgery.

Total plasma antioxidant status (TPAS), lipid peroxide concentration (LPX) and cardiac troponin T (cTnT) were measured in 24 patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). Samples were obtained preoperatively and at 1.5 h, 6 h, 24 h and 72 h after CPB.

Financing HIV service provision in England: estimated impact of the cost of antiretroviral combination therapy.

The objective of this study was to provide population-based estimates on the cost of HIV service provision in England and the use of dual or triple antiretroviral combination therapy. Contemporary cost estimates of treating HIV-infected individuals by clinical stage of HIV infection (indexed to 1995/96 prices) were linked to the number of diagnosed HIV-infected individuals using statutory medical services in England during 1996. Two cost measures were used: the first one was based on average hospital prices derived from a number of English HIV units.

Reduced adenosine uptake accelerates ischaemic block of population spikes in hippocampal slices from streptozotocin-treated diabetic rats.

We have used rats with streptozotocin-induced diabetes to investigate the effects of hyperglycaemia-mediated impaired nucleoside uptake on the actions of endogenous adenosine in hippocampal slices. In control tissue under conditions of anoxia and aglycaemia the rise in the extracellular adenosine concentration resulted in complete inhibition of synaptic activity in about 2 min. In slices from previously hyperglycaemic rats the inhibition of synaptically mediated responses occurred significantly faster, although this change could be prevented by insulin treatment.

Natural history and molecular biology of hepatitis G virus/GB virus C.

Background: The hepatitis G virus (HGV) or GB virus C (GBV-C) is a new member of the Flaviviridae family. The virus is transmitted by transfusion of blood, infusion of some blood products, and by parenteral exposure to blood during intravenous drug use (IVDU) and haemodialysis. Transmission from mother to infant and by sexual contact has also been documented.

Peter B. Samuels Award. Restenosis after percutaneous transluminal angioplasty.

Background: Determine the feasibility of studying the natural history of the atherosclerotic plaque following percutaneous transluminal angioplasty (PTA), using duplex scanning.

Methods: Twenty-three patients with 40 stenoses (>70% and <5 cm in length) in the iliac and femoro-popliteal segments were studied by duplex scanning before PTA, on day 1, weekly for 8 weeks, and at 3 months, 6 months, and 1 year. The following measurements were made: thickness of the plaque, minimal lumen diameter (MLD), and peak systolic velocity ratio (PSVR).

Structure of chordae tendineae in the left ventricle of the human heart.

The bicuspid (mitral) valve complex of the human heart consists of functional units which include the valve leaflets, chordae tendineae and the papillary muscles. The mechanical properties of these functional units depend to a large extent on the link between the muscle and the valve. This link is usually arranged in a branching network of avascular tendinous chordae composed of collagen and elastic fibres, which transmit contractions of the papillary muscle to the valve leaflets.

Selective regulation of Bcl-XL by a Jak kinase-dependent pathway is bypassed in murine hematopoietic malignancies.

Bcl-2 family proteins are key regulators of apoptosis and function as cell death antagonists (e.g., Bcl-2, Bcl-XL, and Mcl-1) or agonists (e.