A simple method for assessing muscle function in common marmosets.

A novel method of assessing muscle function in the common marmoset was developed as part of a multidisciplinary long-term study. The method involved home cage presentation of a weight-pulling task. Over a 4-5 month period, 38 of 42 animals were successfully trained to displace weights of up to 920 g (mean 612+/-20 g). Performance, following initial training, was stable and independent of gender or body weight.

An extensive monoclonal antibody panel for the phenotyping of leukocyte subsets in the common marmoset and the cotton-top tamarin.

New World monkeys are valuable animal models to study human diseases. To determine the phenotype of cells involved in immune responses, we used flow cytometry to screen a large panel of anti-human monoclonal antibodies (mAb) for cross-reactivity with cells of the common marmoset and the cotton-top tamarin. Certain antigens (e.g., CD2, CD8, CD20) are well conserved. However, CD10, CD23, and CD33 showed a clear discrepancy in their reaction patterns in both species, indicating that significant differences on the epitope level occurred during evolution. Epstein-Barr virus-transformed B-cell lines were shown to be a valuable tool for screening B-cell-specific reagents. In some cases, fluorescein isothiocyanate (FITC) and phycoerythrin (PE) modification of mAbs had a negative effect on the binding capacity, which stressed the importance of choosing the right label. Despite the fact that some CD antigens were not detected, adequate numbers of cross-reactive mAbs were identified to perform extensive studies on immunological functions in both the common marmoset and the cotton-top tamarin.

Biological consequences of multiple vaccine and pyridostigmine pretreatment in the guinea pig.

An investigation of the possible interactions between combinations of vaccines and pyridostigmine bromide (PB) has been undertaken in the guinea pig. This study is part of a research programme funded by the UK Government to determine any effects of the pretreatment regimes given to UK Forces during the Persian Gulf conflict of 1990-1991. The study was designed to simulate PB administration and to model multiple vaccination protocols that were experienced by UK Forces, modelling a "worst case" situation in which all ten vaccines and PB were administered within a short period of time. Seven of the vaccines were health and hygiene (H+H) vaccines given to protect against endemic diseases and two vaccines to protect against the biological warfare agents anthrax and plague. In addition, pertussis vaccine was administered as an adjuvant to reduce the time to achieve immunity against anthrax. Four groups of eight animals were treated with 1/20th, 1/10th or 1/5th human doses of vaccines or vehicles, respectively. The PB or saline was delivered by implanted 28 day mini-osmotic pumps to achieve a mean red blood cell acetylcholinesterase (AChE) inhibition of around 30%. Body weight, temperature, immunological response, biochemical indices and spontaneous activity were monitored for 72 days. Although immunological responses to bacterial vaccines were observed, there were no remarkable findings in the parameters measured other than minor changes in body weight (4.9% decrease at the 1/5th human dose of vaccines) and temperature increases in response to vaccination. Animals in all groups remained generally healthy and active without visible adverse signs throughout the study. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.

Captopril and hydrochlorthiazide--a safe antihypertensive for use in general practice?

The combination of captopril and hydrochlorthiazide was assessed in 15 hypertensive patients in a general practice setting. The first aim was to determine whether the fall in blood pressure, noted after the first dose of an ACE inhibitor given alone, became unacceptable when the drug was given with a diuretic. The second aim was to assess the impact of the ACE inhibitor on the biochemical abnormalities associated with thiazide diuretic therapy. The drug combination markedly reduced blood pressure but not below 110 systolic after the first dose. In the long-term the treatment significantly lowered blood pressure but did not produce any significant or clinically relevant changes in serum chemistry.

Alcohol consumption--a risk factor for hemorrhagic and non-hemorrhagic stroke.

PURPOSE: The risks of alcohol consumption and its association with stroke were studied in 621 patients with stroke and 573 control subjects using case-control methods. PATIENTS AND METHODS: Patients with stroke were subdivided into 193 with subarachnoid hemorrhage, 91 with intracerebral hemorrhage, and 337 with cerebral infarction. Data on recent alcohol consumption were obtained by questionnaire in patients with stroke and compared with data from an occupational screening survey in control subjects. RESULTS: Relative risks, adjusted for confounding variables, exhibited J-shaped associations with increasing levels of alcohol consumption classified into four categories--abstainer, 1 to 90 g, 100 to 390 g, and greater than or equal to 400 g weekly). The individual risks were 1, 0.7, 0.5, and 1.3 for subarachnoid hemorrhage; 1.0, 0.6, 0.5., and 2.5 for intracerebral hemorrhage, and 1.0, 0.6, 0.7, and 2.4 for cerebral infarction for men and women combined. CONCLUSIONS: The results suggest that low levels of alcohol consumption may have some protective effect upon the cerebral vasculature, whereas heavy consumption predisposes to both hemorrhagic and non-hemorrhagic stroke.

Sodium, potassium, body mass, alcohol and blood pressure in three United Kingdom centres (the INTERSALT study).

Standardised data on blood pressure, 24 h urinary electrolyte excretion, body mass index (BMI) and alcohol intake were collected as part of the INTERSALT study in 598 men and women aged 20-59 years, selected randomly from three population groups in the United Kingdom. For the three centres combined, mean systolic blood pressure was 121.4 mm Hg and diastolic pressure 72.1 mm Hg, urinary sodium excretion 152.1 mmol/24 h, urinary potassium excretion 61.0 mmol/24 h, urinary sodium/potassium ratio 2.64 and BMI 25.2 kg/m2. Prevalence of heavy alcohol drinking in men (greater than or equal to 300 ml/week) was 27.5 per cent. Applying overall INTERSALT regression coefficients to the United Kingdom data suggested that modest changes in average sodium and potassium intakes, together with reductions in the prevalence of obesity and (in men) of heavy alcohol drinking could lead to important reductions in average population blood pressures and the prevalence of hypertension. The potential of this multifactorial approach to blood pressure control was illustrated by stratifying individuals within each of the United Kingdom centres by sodium and potassium excretion, BMI and alcohol intake. The 20 (out of 299) men considered at 'lower risk' for high blood pressure with respect to the above variables had systolic pressure lower by 11 mm Hg (P less than 0.01); for the 27 (out of 299) 'lower risk' women, systolic pressure was lower by 5 mm Hg (P = 0.06). These non-pharmacological approaches towards more favourable blood pressure levels could be accompanied by reductions in mortality from stroke and coronary heart disease.

Cigarette smoking. A risk factor for hemorrhagic and nonhemorrhagic stroke.

Cigarette smoking habit was studied in 621 patients with stroke and in 573 control subjects using case control methods. There was an excess of smokers among the stroke group when compared with control subjects. Relative risks of cigarette smokers compared with nonsmokers, after adjustment for the possible confounding variables for subarachnoid hemorrhage, intracerebral hemorrhage, and cerebral infarction, were 4.5, 1.8, and 3.2 for men and 2.5, 1.3, and 2.3 for women, respectively. For all subtypes of stroke combined, the increased relative risk was related to the daily intake of cigarettes, the heaviest smokers having a higher relative risk than that for light smokers. The estimated increase in relative risk among smokers was 1.5 for each 10 cigarettes smoked daily in both men and women. We conclude that cigarette smoke may be an important preventable factor for both hemorrhagic and nonhemorrhagic stroke.

Operative or conservative treatment for trochanteric fractures of the femur. A randomised epidemiological trial in elderly patients.

All elderly patients with extracapsular hip fractures seen in hospitals in Newcastle upon Tyne over a 12-month period were studied and followed up for six months. At one of the hospitals, patients were randomised to treatment by AO dynamic hip-screw or by traction. Complications specific to the two treatments were low, and general complications, six-month mortality and prevalence of pain, leg swelling and unhealed sores, showed no difference between the two modes of treatment. Operative treatment gave better anatomical results and a shorter hospital stay, but significantly more of the patients treated by traction showed loss of independence six months after injury.

A community case-control study of alcohol consumption in stroke.

This study examines the hypothesis that there may be a clinically important association between alcohol intake and stroke. Alcohol consumption and the haematological and biochemical markers of alcohol intake were studied in hospital admissions for stroke and compared with community based control subjects from an occupational screening survey. In males, moderate to heavy alcohol consumption (greater than 30 units per week) was associated with an increased relative risk of stroke. Light drinking (less than 30 units per week) was associated with reduced relative risk when compared to teetotallers. The relative risk of stroke in moderate and heavy consumers of alcohol compared with teetotallers was elevated 1.8 times. Similar patterns of risk were present for increasing levels of aspartate transaminase and uric acid. Relative risk was increased for all levels of gamma-glutamyl transferase above the lowest. There was a decrease in relative risk associated with increasing levels of mean erythrocyte cell volume though this did not achieve statistical significance. There were few heavy drinkers among the female cases or controls. We conclude that high alcohol intake may be a significant preventable risk factor particularly among male strokes.

The complications of surgical treatment of displaced fractures of the olecranon.

Forty-eight patients who had undergone internal fixation of a displaced fracture of the olecranon by either a tension band technique (34 patients) or screwing (14 patients) were reviewed. The functional results after at least 2 years were equally good with both methods, but there was a considerably higher rate of separation at the fracture after screwing than after inserting a tension band. The technical quality of the fixation was open to criticism in half the cases in each group, and the implications of this are discussed.

The measurement of skin blood flow in peripheral vascular disease by epicutaneous application of Xenon133.

Radioactive xenon133 applied epicutaneously was used to study the skin blood flow below the knee in sixteen normal subjects, in eight patients with peripheral vascular disease not requiring amputation, and in a blind study of twenty-nine patients requiring amputation. Following these twenty-nine amputations, the flow rates were made known and correlated with the rates of healing. When the flow rates were above 1.5 milliliters per minute per 100 grams of tissue (skin), the wounds generally healed. In thirteen other patients, Syme or below-the-knee amputations were performed on the basis of the flow rates, and all of the wounds healed. The test, therefore, is now used routinely prior to amputation for peripheral vascular disease as an adjunct to clinical judgment in the determination of the level of amputation.

Syme's amputation. Follow-up study of weight-bearing in sixty-eight patients.

Sixty-eight patients with Syme amputations resulting from industrial injuries were reviewed. The amount of end-weight-bearing was measured with a capacitance transducer. The majority of patients required fitting with a prosthesis designed to relieve end-weight-bearing. The old-fashioned prosthesis with a leather corset was the most effective in achieving reduction of end-weight-bearing.

Effect of prolonged saline-exposure on sodium transport across frog skin.

1. Differences in Na transport between skins from Rana temporaria and R. esculenta maintained for up to several weeks in water or 0.7% saline (0.7 g NaCl in 100 ml. H(2)O), with and without daily injections of 4% saline (4 g NaCl in 100 ml. H(2)O), were measured, in vitro.2. In saline-treated skins, the following changes were found:(a) An increased Na content.(b) A consistent decrease in short-circuit current (I(sc)).(c) An increased d.c. resistance, R, the consistency of which varied with the anion content of the Ringer solution.(d) A highly significant fall in Na influx, accounting for the reduced I(sc); a small reduction in Na efflux was not significant, statistically.(e) The Pitressin-induced increment in I(sc) was usually considerably lower compared with that in water-exposed skins; considered relative to the pre-Pitressin values, however, there were no clear differences.(f) By calculation from the changes in resistance (R) caused by replacement of outer Na(2)SO(4) Ringer by K(2)SO(4) Ringer solution,I. E(0), the electromotive force of the active sodium transport system, was moderately, but significantly, reduced,II. R(shunt), the shunt path resistance, was moderately, but significantly, increased, andIII. R(ser), the series path resistance, was considerably, and highly significantly, increased.(g) K influx from outer K(2)SO(4) Ringer solution was reduced.3. Differences between skins from water-exposed and saline-treated frogs persisted, in vitro, despite the occurrence of anionic-dependent acute changes after mounting in Ringer solution.4. There were seasonal changes in I(sc), and in the effects of saline treatment.5. The findings are discussed in terms of decreased permeability of outer barriers to ion-diffusion, and reduced activity of a Na pump.