The impact of duplex scanning on vascular practice.

Duplex ultrasonography has gained enormous importance in the vascular practice over the last decade. Technological development with the colour application as well as the high resolution imaging have altered the diagnostic approach, treatment and follow-up of the vascular patients. Research on the epidemiology and natural history of atherosclerosis and thrombosis has also been founded based on the ultrasonic applications, improving our understanding in the pathophysiology of the vascular disease.

General practitioners' immediate management of men presenting with urethral symptoms.

Objectives: To describe the immediate reported management, by general practitioners (GPs), of men presenting with symptoms of urethral discharge, or dysuria only.

Subjects: All 692 GPs in practice in Brent, Harrow, Ealing, Hammersmith, and Hounslow (UK).

Method: Data were collected using a GP completed questionnaire concerning the management of the last male patient seen, aged less than 40 years, complaining of urethral discharge, and the last male patient under 40 years complaining of dysuria only.

Refining treatment approaches in obsessive-compulsive disorder.

Obsessive-compulsive disorder (OCD) has emerged as a common but frequently hidden psychiatric disorder which inflicts an intolerable burden on sufferers and demands effective management. For many years, however, OCD was considered treatment resistant and it is only in the past 15 years that effective therapy has become available. The discovery that the symptoms of OCD could be controlled with clomipramine, but not with other tricyclic antidepressants, was a crucial step in the development of effective management of the condition.

Cardiovascular and catecholamine changes induced by supine exercise and upright posture in vasovagal syncope. Comparisons with normal subjects and subjects with sympathetic denervation.

The haemodynamic and catecholamine responses to supine leg exercise were studied in vasovagal syncope (n = 10), pure autonomic failure (n = 10) and in control (n = 10) subjects. With exercise, blood pressure increased in controls; with a smaller rise in vasovagal syncope, and a substantial fall in pure autonomic failure. Heart rate increased similarly in controls and vasovagal syncope, but less in pure autonomic failure.

Recovery from depressive illness does fit an exponential model.

A very large number of therapeutic trials of antidepressant drugs have been reported in the scientific literature. Until now, the comparison of one drug with another, or with placebo, has been performed typically by comparing the scores on depression rating scales of the two groups of patients at fixed points of time after the beginning of therapy. It was postulated in 1989 that the curves of the recovery scores followed an exponential curve of the formula y = ae-bx + c.

Dendritic shrinkage and dye-coupling between rat hippocampal CA1 pyramidal cells in the tetanus toxin model of epilepsy.

A small dose of tetanus toxin injected into the rat hippocampus produces a chronic model of temporal lobe epilepsy. We have examined whether morphological changes occur in hippocampal CA1 pyramidal cells in this model by using intracellular injections of biocytin. Eight weeks after the injection of tetanus toxin, significantly more "dye-coupled' cells were found in this group than in the buffer (control) injected group (63% compared with 7%).

No evidence for linkage of chromosome 22 markers to schizophrenia in southern African Bantu-speaking families.

Previous studies have demonstrated possible linkage between chromosome 22 and one of the hypothesized schizophrenia susceptibility genes. Interpretation of these data, however, is not straightforward: although not significant at the level traditionally accepted to demonstrate linkage, reported lod scores were greater than should have occurred by chance for an unlinked marker based on simulation studies. Further, these studies used sample populations which were either of mixed nationality and ethnicity, or mixed ethnic ancestry from one country.

Intra-observer and inter-observer variation in the histopathological assessment of chronic viral hepatitis.

Background/aims: The way in which liver biopsies showing chronic hepatitis are reported is undergoing re-evaluation. A related question is how the inflammatory and fibrotic changes in these liver biopsies can be semi-quantitatively assessed so that comparisons can be made between groups of patients and the effect of treatment on disease progression studied.

Methods: We have carried out a blinded trial in which 20 cases of chronic viral hepatitis were assessed by five histopathologists, using the Knodell and Scheuer scoring systems (two of the most commonly used systems), on two separate occasions.

Impaired absorption of zidovudine in patients with AIDS-related small intestinal disease.

Objectives: To investigate the effect of small intestinal disease (SID) on the absorption of zidovudine (ZDV) in patients with AIDS.

Methods: Fourteen fasted homosexual men with AIDS received a single oral dose of ZDV (5 mg/kg). Nine subjects had clinical evidence of intestinal disease (chronic diarrhoea with wasting) confirmed by reduced fat absorption measured indirectly using the 14C-triolein test.

Platelet-derived growth factor (PDGF): actions and mechanisms in vascular smooth muscle.

1. PDGF is a highly hydrophilic cationic glycoprotein (M(r) 28-35kDa) produced by platelets, monocyte/macrophages, endothelial cells and vascular smooth muscle cells under some conditions. 2.

Hepatitis C and bile duct loss.

Aim: To assess whether bile duct loss is associated with the bile duct damage induced by chronic hepatitis C.

Methods: Sections were examined from 171 liver biopsy specimens from patients with chronic hepatitis C, 98 biopsy specimens from patients with chronic hepatitis B, 25 postmortem specimens from patients with no evidence of liver disease, and 23 patients who underwent protocol liver biopsy at the time of cholecystectomy.

Results: The bile duct:portal tract ratio for the hepatitis C group was 0.

Correlation between total and CD4 lymphocyte counts in HIV infection: not making the good an enemy of the not so perfect.

The aim of this study was to assess the correlation and average cost of total lymphocyte count compared with CD4 count as a broad estimate of immunosuppression in HIV-1 infected individuals. Spearman's partial rank correlation were calculated between total lymphocyte count, absolute CD4 count and CD4 per cent stratified by stage of HIV-1 infection for routinely collected samples. Data were collected prospectively from a T cell-subset register combined with clinical data obtained retrospectively from case notes of HIV-infected patients managed at St Mary's Hospital, London 1982-1991.

Transport of macromolecules through microvascular walls.

This review addresses the long-standing controversy over the principal mechanisms of transport of macromolecules through the endothelium of microvessels of 'normal' permeability. Two types of mechanism have been proposed: convective transport through 'large pores' in the endothelium: transport via vesicles (transcytosis). The different techniques for estimating microvascular permeability to macromolecules are described and values for microvascular permeability to serum albumin in different tissues are tabulated.

Neurohumoral, peptidergic and biochemical responses to supine exercise in two groups with primary autonomic failure: Shy-Drager syndrome/multiple system atrophy and pure autonomic failure.

The neurohumoral, peptidergic and biochemical responses to supine leg exercise were studied in two groups with primary autonomic failure: Shy-Drager syndrome (SDS, n = 15) and pure autonomic failure (PAF, n = 15), to determine if these accounted for exercise-induced hypotension and the greater blood pressure (BP) fall in PAF. Responses were compared to normal subjects (controls, n = 15), in whom BP rose with exercise. Resting plasma noradrenaline (NA) was higher in controls than SDS, and was lowest in PAF.

Variation in the tumor necrosis factor-alpha gene promoter region may be associated with death from meningococcal disease.

Tumor necrosis factor-alpha (TNF-alpha) plays a central role in the pathophysiology of sepsis. Levels of TNF-alpha are directly correlated with severity in meningococcal disease (MD). A polymorphism in the promoter region of the TNF-alpha gene is associated with differences in the secretion of TNF-alpha.

Pseudopyropoikilocytosis: a striking artefact.

The blood films both of patients with hereditary pyropoikilocytosis and of those with severe thermal burns are characterised by budding erythrocytes and the presence of microspherocytes. Recently, a fourth example of similar morphological features, caused by overheating of a blood specimen in a motor vehicle during transport to the laboratory, has been observed. It is important to be aware of this artefact as failure to recognise it is likely to lead to diagnostic confusion and unnecessary further testing, causing inconvenience to the patient.

Regulation of aromatase and sulphatase in breast tumour cells.

In situ oestrogen synthesis makes an important contribution to the high oestrogen concentration found in breast tumours. Cytokines, including interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF alpha), have been shown to regulate aromatase activity in fibroblasts derived from normal and malignant breast tissues. In the present study, the ability of other cytokines in the IL-6 superfamily (IL-11 and oncostatin M) to stimulate aromatase activity has been confirmed.

Theoretical studies of steady-state transcapillary exchange in countercurrent systems.

Objective: As a first step in modeling microvascular exchange in the renal medulla, we developed mathematical models to explore the effects of blood flow, permeability, and anatomical arrangement of microvessels on the steady-state distribution of solute in the blood and the interstitial fluid (ISF).

Methods: Single capillaries and countercurrent capillary loops were used to model microvessels that were surrounded by a secretory epithelium over either the whole or part of the capillary length. Solute concentration in the vessels and the ISF were derived analytically.

Efficacy and tolerability of milnacipran: an overview.

The relative benefits and risks of milnacipran, a novel antidepressant which selectively inhibits the reuptake of serotonin and noradrenaline, have been evaluated in comparative trials against tricyclic antidepressants (TCAs) or selective serotonin reuptake inhibitors (SSRIs). A total of 2462 patients with major depressive disorders have been investigated. At the optimal dose (50 mg twice a day), the efficacy of milnacipran was equivalent to that of the TCAs, with response rates of approximately 65% in both cases.