Ultra high field NMR spectroscopic studies on human seminal fluid, seminal vesicle and prostatic secretions.

Ultra high field 1H-NMR spectroscopic methods have been used to analyse the composition of seminal fluid and its component secretions, prostatic and seminal vesicle fluids from normal human subjects and those with vasal aplasia and non-obstructive infertility. The 1H-NMR spectrum of whole seminal fluid is extremely complex and many resonances are extensively overlapped in single pulse spectra even when measured at 600 or 750 MHz 1H resonance frequency. A combination of 2-D 1H-NMR methods (including J-Resolved and various 1H homonuclear correlation and 1H-13C heteronuclear correlation techniques) were applied at 600 or 750 MHz in order to extensively assign the signals from the organic components of seminal fluid.

Proton spectroscopy in HIV infection: relaxation times of cerebral metabolites.

In vivo proton spectroscopy has demonstrated abnormalities in the cerebral metabolite ratios from subjects with acquired immunodeficiency syndrome (AIDS). Some of the sequences employed are subject to T1 or T2 weighting, which may affect spectroscopic interpretation. The relaxation times of choline (Cho), creatine (Cr), and N-acetyl (NA) resonances have been estimated at 1.

The introduction of external cephalic version at term into routine clinical practice.

External cephalic version (ECV) at > or = 37 weeks' gestation in suitable women with breech presentation was introduced in 1991 as a new management option at a University Teaching Hospital. After 16 months, the policy was audited by analysing a prospectively collected database of women offered ECV at term and by a retrospective review of all breech deliveries during the same period. A total of 52 women had ECV attempted with an immediate success rate of 46%.

The effect of suppressive oral acyclovir on the psychological morbidity associated with recurrent genital herpes.

Objectives: To assess the psychological impact of recurrent genital herpes and to determine if longterm acyclovir has any impact on this morbidity.

Setting And Subjects: Patients with frequently recurring genital herpes attending a department of genitourinary medicine who were considered suitable for longterm acyclovir.

Methods: Patients completed an 80 item, self-administered psychological questionnaire before starting acyclovir and every three months for one year.

Acquired immunodeficiency syndrome (AIDS) risk in recent and long-standing human immunodeficiency virus type 1 (HIV-1)-infected patients with similar CD4 lymphocyte counts.

The loss of CD4 lymphocytes is known to be an important component of human immunodeficiency virus type 1 (HIV-1) pathogenesis. It remains unclear, however, whether the importance of the CD4 lymphocyte count is such that individuals who have been infected for widely different lengths of time, but for whom the CD4 lymphocyte count is the same, have the same risk of developing acquired immunodeficiency syndrome (AIDS). The authors directly addressed this question for 111 HIV-1-infected hemophiliacs who had been followed for up to 12 years from seroconversion and for whom a median of 16 CD4 lymphocyte counts had been made.

Uteroplacental resistance index: analysis of intra- and interobserver variability.

The aim of this study was to assess the intra- and interobserver variability of second-trimester uteroplacental continuous-wave flow velocity waveforms. The left and right uterine and arcuate resistance indices were measured in women having their routine booking scan at 16-24 weeks' gestation. Four experiments assessed the intra-observer between-frame variability, the intraobserver beat-to-beat variability, the intraobserver temporal variability, and the interobserver variability, using the limits-of-agreement method.

Can environmental factors explain the epidemiology of schizophrenia in immigrant groups?

Recent evidence suggests that high rates of schizophrenia in first- and second-generation immigrants could be due to exposure to environmental factors such as viral infections in the host country. These findings are discussed alongside parallel data relating to other diseases such as multiple sclerosis and diabetes mellitus. It is argued that in each case the interaction between the environmental agent and constitutional factors related to the immune system need to be considered.

The relationship of uterine and umbilical Doppler resistance to fetal and placental protein synthesis in the second trimester.

The relation of uteroplacental and umbilical Doppler resistance index (RI) to peripheral levels of alphafetoprotein (AFP), human chorionic gonadotrophin (hCG), human placental lactogen (HPL), Schwangerswaft protein (SP1), pregnancy-associated placental protein A (PAPP-A) and insulin-like growth factor binding protein 1 (IGP-BP1) at 16-24 weeks was established in a cross-sectional study of 183 unselected singleton pregnancies. There was an association between high values of uteroplacental RI and high hCG levels, and high umbilical RI values with high hCG and HPL levels. Thus, in the mid-trimester, the levels of some placental proteins seem to be related to placental resistance.

The design of prospective epidemiological studies: more subjects or better measurements?

Prospective epidemiological studies which seek to relate potential risk factors to the risk of disease are subject to appreciable biases which are often unrecognized. The inability to precisely measure subjects' true values of the risk factors under consideration tends to result in bias towards unity in the univariate relative risks associated with them--the more imprecisely a risk factor is measured, the greater the bias. When correlated risk factors are measured with different degrees of imprecision the adjusted relative risk associated with them can be biased towards or away from unity.

Height, occupation and back pain in a national prospective study.

Back pain is an important public health problem but there is a paucity of knowledge about risk factors and causal mechanisms. Previous studies have shown that tall men are more at risk of back pain, although observations in women have been less consistent. This paper presents findings from a national longitudinal study of 3262 men and women aged 43 yr.

Flow cytometric observations on the in vivo use of Fab fragments of a chimaeric monoclonal antibody to platelet glycoprotein IIb-IIIa.

Fluorescence flow cytometry (FC) was employed to monitor the platelet surface in humans receiving intravenous infusions of Fab fragments of a chimaeric (murine/human) construct of monoclonal antibody 7E3, which binds to the fibrinogen receptor (glycoprotein IIb-IIIa) and inhibits platelet aggregation. Platelet surface-bound chimaeric 7E3-Fab (c7E3-Fab) was measured using a fluorescein-conjugated polyclonal anti-7E3 antibody and residual c7E3-Fab binding capacity was measured using fluorescein-conjugated c7E3-Fab. Turbidometrically measured platelet aggregation response to ADP was shown to be a linear function (r = 0.

Combined 17 alpha-hydroxylase/17,20-lyase deficiency caused by heterozygous stop codons in the cytochrome P450 17 alpha-hydroxylase gene.

Objective: To determine the genetic defect underlying congenital adrenal hyperplasia due to 17 alpha-hydroxylase deficiency in a genetic female.

Design: Blood samples were used as a source of genomic DNA. A library of size selected genomic DNA sequences was prepared.

Measurement of hemoglobin flow and blood flow by near-infrared spectroscopy.

A noninvasive method of measuring hemoglobin flow through an organ by near-infrared spectroscopy (NIRS) is described that allows blood flow to be calculated. The method is derived from the Fick principle and uses a small change in arterial oxyhemoglobin concentration (brought about by a change in the fractional inspired O2 concentration) as an intravascular tracer. Changes in deoxyhemoglobin and oxyhemoglobin concentrations are quantified by monitoring variations in the absorption of near-infrared light in the organ, thus providing a measure of tracer accumulation.

Hypoglycaemia: a common problem among uncomplicated newborn infants in Nepal.

Among a cross-sectional sample (stratified by weight and age after birth) of 226 uncomplicated term newborns from the delivery and postnatal wards of a busy government maternity hospital in Kathmandu, the period prevalence of hypoglycaemia (corrected blood glucose of < 2.6 mmol/l) during the first 50 hours after birth was 38 per cent. (This compares with a reported prevalence rate of 12 per cent from studies of uncomplicated term newborns in the UK.

Ultrasonic fetal weight estimation: analysis of inter- and intra-observer variability.

Standard ultrasound measurements were performed by two observers in 40 third-trimester fetuses. Observers were blinded to the results of the measurements. Estimated fetal weight (EFW) was calculated using two published formulae.

Chemical analysis of post-lithotripsy stone fragments: a critical evaluation.

A scheme for the chemical microanalysis of renal stone fragments recovered from urine voided immediately after lithotripsy has been developed and evaluated. The analytical procedure includes assay of calcium, magnesium, phosphate, oxalate and urate and has been applied to 78 such urine samples. Problems relating to co-existing crystalluria and blood and urine contaminants have been recognised and overcome.

Genetically engineered kidneys.

We review the available methods of creating genetically engineered kidneys. These include transgenic technology to introduce novel genes or delete existing genes and methods of gene transfer into the post-natal or adult kidney. The use of such technology has provided insights into renal development and growth and created new animal models of human diseases.

Role of beta 2-glycoprotein I and anti-phospholipid antibodies in activation of protein C in vitro.

Aims: To investigate the effect of beta 2-glycoprotein I (beta 2 GPI) on the thrombin/thrombomodulin dependent activation of protein C; and to determine whether beta 2 GPI dependent anticardiolipin antibodies have any effect.

Methods: Protein C was activated by thrombin in the presence of thrombomodulin and phospholipid vesicles in an in vitro system. The effect of adding purified beta 2 GPI to this system was observed.

Physical health status at 36 years in a British national birth cohort.

In a nationally representative British sample of over 3000 men and women aged 36 years, those in the best or worst of health were identified on the basis of measured blood pressure, lung function and body weight, self reported health problems and disability, and recent hospital admission. Serious illness in earlier life was strongly predictive of current adult health status. Even after adjusting for this and for current social circumstances and health related behaviour, those who came from poorer family backgrounds or were least well educated did not have an equal chance of being in the best of health at 36 years.

Effects of intermittent pneumatic compression of the foot on the microcirculatory function in arterial disease.

Objective: The venous pump of the foot assists blood returning to the heart. The aim of this study was to evaluate the effect of mechanical activation of the foot pump on the microcirculation of the skin in patients with peripheral occlusive arterial disease.

Design: Single parallel group comparing patients with arterial disease to normal control subjects.

Two patterns of calcification in primary (physeal) and secondary (epiphyseal) growth cartilage.

It is generally stated that the process of cartilage calcification and ossification is the same in the physeal (primary growth center) and epiphyseal (secondary growth center) growth plates. Reexamination of osteophyte growth led to the proposal that these growth plates differ. This proposition was tested by examining rabbit and human material from both sites before and after maceration; both tissue preparations were processed for light microscopy, and the macerated tissues were also studied by scanning electron microscopy (SEM).

Ultrasonic estimation of fetal weight: use of targeted formulas in small for gestational age fetuses.

Objective: To derive a formula for calculating fetal weight in small for gestational age (SGA) fetuses and to determine prospectively whether the use of such a targeted formula reduces birth weight prediction errors.

Methods: Standard ultrasonic measurements were made in 159 SGA fetuses within 7 days of delivery. Three classes of fetal weight formulas (linear, quadratic, and cubic) were fitted to the data using stepwise regression analysis.

FGF-4 maintains polarizing activity of posterior limb bud cells in vivo and in vitro.

The polarizing region is a major signalling tissue involved in patterning the tissues of the vertebrate limb. The polarizing region is located at the posterior margin of the limb bud and can be recognized by its ability to induce additional digits when grafted to the anterior margin of a chick limb bud. The signal from the polarizing region operates at the tip of the bud in the progress zone, a zone of undifferentiated mesenchymal cells, maintained by interactions with the apical ectodermal ridge.

Assessment of elderly people in general practice. 4. Depression, functional ability and contact with services.

The aim of this study was to look at the interrelationship between depression, physical disability and contact with services. In a random sample of 239 people aged 75 years and over from nine general practices in north London, depression (as measured by a shortened version of the comprehensive assessment and referral evaluation schedule) was found to be significantly associated with being a woman, and inability to perform a number of activities of daily living. Consumption of three or more prescribed medicines, a home visit by the general practitioner in the previous three months and contact with health visitors and home helps were all significantly more likely among depressed patients.