PubMed Health⌕ Search

Biomedical subjects

A Shirley

Publications and source records attributed to A Shirley.

18 recordsLinked to original sources
PubMed2005

The control of hypertension by use of coconut water and mauby: two tropical food drinks.

In this study, the authors investigated the effect of regular consumption of two tropical food drinks, coconut (Cocos nucifera) water and mauby (Colubrina arborescens), on the control of hypertension. Twenty-eight hypertensive subjects were assigned to four equal groups and their systolic and diastolic blood pressures recorded for two weeks before and then for another two weeks while receiving one of four interventions. One group (the control) received bottled drinking water, the second group received coconut water, the third received mauby and the fourth group, a mixture of coconut water and mauby. Significant decreases in the mean systolic blood pressure were observed for 71%, 40% and 43% respectively of the groups receiving the coconut water, mauby and the mixture (p < or = 0.05). For these groups, the respective proportions showing significant decreases in the mean diastolic pressure were 29%, 40% and 57%. For the group receiving the mixture, the largest decreases in mean systolic and mean diastolic pressure were 24 mmHg and 15 mmHg respectively; these were approximately double the largest values seen with the single interventions.

Beverages↗
PubMed2002

Problem-based compared with traditional methods at the Faculty of Medical Sciences, University of the West Indies: a model study.

The University of the West Indies (UWI) comprises three campuses located on three different islands. Two of the Campuses, Mona in Jamaica and St Augustine in Trinidad & Tobago offer full medical programmes, i.e. both basic sciences and clinical training. At Cave Hill, where basic sciences courses are not offered, students are drawn from the traditional school at Mona or the Problem Based Learning (PBL) school at St Augustine to follow a common clinical programme. After 24 months of clinical training consisting of a minimum of 12 clerkships these students take identical examinations in Medicine & Therapeutics, Surgery and Obstetrics & Gynaecology. In this paper the results of the final clinical examinations at Cave Hill for the five-year period 1995-99 have been analysed, comparing the performances of students drawn from Mona with those from St Augustine. We found that, except for a few isolated cases, there were no significant differences in the performance of the two groups of students. These results suggest that the delivery of a significant component of a basic sciences programme by a well-planned PBL system is unlikely to produce substandard students at the end of their clinical training.

Clinical Clerkship↗
PubMed2000

Drug treatment of hypertension in older people: relieving the pressure.

Hypertension is very common, occurring in over 50% of older people, and is a major risk factor for stroke and ischaemic heart disease. Based on systematic reviews there is evidence to show that drug treatment of hypertension in older people saves lives and prevents unnecessary morbidity. There is also strong evidence to support the use of diuretics as first line agents. Quality of life does not appear to be reduced by antihypertensive drug therapy, although more high quality research is needed. Through the use of drug treatment older people with hypertension can continue to contribute to society and live active lives.

Aged↗
PubMed2000

Functional motor unit failure precedes neuromuscular degeneration in canine motor neuron disease.

Hereditary canine spinal muscular atrophy (HCSMA) features rapidly progressive muscle weakness that affects muscles in an apparent proximal-to-distal gradient. In the medial gastrocnemius (MG) muscle of homozygous HCSMA animals, motor unit tetanic failure is apparent before the appearance of muscle weakness and appears to be presynaptic in origin. We determined whether structural changes in neuromuscular junctions or muscle fibers were apparent at times when tetanic failure is prevalent. We were surprised to observe that, at ages when motor unit tetanic failure is common, the structure of neuromuscular junctions and the appearance of muscle fibers in the MG muscle were indistinguishable from those of symptom-free animals. In contrast, in more proximal muscles, many neuromuscular junctions were disassembled, with some postsynaptic specializations only partially occupied by motor nerve terminals, and muscle fiber atrophy and degeneration were also apparent. These observations suggest that the motor unit tetanic failure observed in the MG muscle in homozygous animals is not due to synaptic degeneration or to pathological processes that affect muscle fibers directly. Together with previous physiological analyses, our results suggest that motor unit failure is due to failure of neuromuscular synaptic transmission that precedes nerve or muscle degeneration.

Animals↗
PubMed1999

Sexual dimorphism in the rabbit masseter muscle: myosin heavy chain composition of neuromuscular compartments.

The myosin heavy chain (MyHC) isoform composition of six adult (>7 months old) male and female rabbit masseter muscles was studied using seven monoclonal antibodies. In matched serial tissue sections, muscle fibers in 10 different neuromuscular compartments were analyzed. Nearly all fibers were found to express one of five phenotypes. They either contained one of four different slow/beta MyHC phenotypes (I(1)-I(4)), nearly all of which co-express cardiac alpha MyHC, or they contained type IIa MyHC. Very few fibers contained slow/beta or cardiac alpha MyHC only or both the alpha/slow/beta and IIa isoforms. Most, but not all, of the compartments studied contained similar proportions of fibers of the five major phenotypes, at least within sex. For 7 of the 10 compartments studied, significant sex differences in the proportion of I(1) and IIa fibers were found. Males contained more IIa fibers and fewer I(1) fibers than females. Fibers of the IIa phenotype were significantly larger than fibers of all of the other phenotypes and larger in males than females.

Animals↗
PubMed1998

Different phenotypes among slow/beta myosin heavy chain-containing fibres of rabbit masseter muscle: a novel type of diversity in adult muscle.

Difference in the phenotype of different mammalian muscle fibres are usually attributed to differences in the expression of the product of different myosin heavy chain (MyHC) genes, which are known as isoforms. We studied differences in phenotype among fibres containing a single MyHC isoform (slow/beta) of the masseter muscle of adult rabbits. Four different monoclonal antibodies to slow/beta MyHC were used to stain serial sections from muscles in males and females. All antibodies recognize a single band on immunoblots and stain the same set of fibres in rabbit postcranial muscles. However, differential staining was observed in the masseter muscles. Antibody BA-D5 reacts with the most fibres, antibody A4.951 reacts with a subset of these fibres, and antibody A4.840 reacts with a subset of these fibres, and antibody A4.840 reacts with a subset of A4.951-positive fibres. Antibody S58 reacts only with an even smaller subset of fibres. Even though differential staining using four antibodies might allow for the expression of as many as 15 different staining patterns, or patterns, or phenotypes, only four were observed on > 99% of over 30 000 fibres studied. In females, nearly 40% of the fibres stain exclusively with antibody BA-D5, while in males, fewer than 8% of the fibres express this phenotype. The proportions of fibres of the other phenotypes do not differ so strikingly with gender. We conclude that an epitope diversity exists among muscle fibres in the adult rabbit masseter and that it is not necessarily a consequence of differences in gene expression. We feel that it is a regulated process and that, at least for some phenotypes, this regulation may be hormonally influenced.

Age Factors↗
PubMed1996

Predictors of African American adolescents' condom use and HIV risk behavior.

This study evaluated predictors of risky and safer behavior in a sample of low-income African American adolescents, assessed their perceptions of the risk associated with their sexual behavior, and examined differences between adolescents who used condoms consistently, inconsistently, or engaged only in unprotected intercourse. African American adolescents (N = 312) completed measures related to AIDS knowledge, frequency of condom use, attitudes toward condoms, and sexual behavior over the preceding 2 months. Multiple regression analyses for the sexually active youths (N = 114) revealed that lower self-efficacy, higher perceived risk, and male gender were associated with high-risk behavior. Positive attitudes toward condoms and younger age had the strongest association with condom use. Consistent condom users were more knowledgeable and held more positive attitudes toward condoms, and nonusers were older. Regardless of their behavior, the adolescents generally did not perceive themselves to be a risk for HIV infection. The findings suggest that precautionary practices (condom use) and high-risk behavior (unprotected sex with multiple partners) may have different correlates. In addition, the data indicate that theoretical models developed with homosexual male populations may also be generalizable to African American adolescents' sexual behavior.

Adolescent↗
PubMed1995

Cognitive-behavioral intervention to reduce African American adolescents' risk for HIV infection.

Two hundred forty-six African American adolescents were randomly assigned to an educational program or an 8-week intervention that combined education with behavior skills training including correct condom use, sexual assertion, refusal, information provision, self-management, problem solving, and risk recognition. Skill-trained participants (a) reduced unprotected intercourse, (b) increased condom-protected intercourse, and (c) displayed increased behavioral skills to a greater extent than participants who received information alone. The patterns of change differed by gender. Risk reduction was maintained 1 year later for skill-trained youths. It was found that 31.1% of youths in the education program who were abstinent at baseline had initiated sexual activity 1 year later, whereas only 11.5% of skills training participants were sexually active. The results indicate that youths who were equipped with information and specific skills lowered their risk to a greater degree, maintained risk reduction changes better, and deferred the onset of sexual activity to a greater extent than youths who received information alone.

Adolescent↗
PubMed1995

Special needs of vulnerable and underserved populations: models, existing and proposed, to meet them.

The rapidly changing environment in the health care industry offers great challenges, especially to those providers who traditionally have cared for vulnerable and underserved populations. These populations have special health care needs resulting from various factors, including race, geography, environment, and lack of access. Some promising existing publicly funded models serve these populations well. Partnerships between these programs and private practitioners would be mutually beneficial to the practices and improve access to care.

Acquired Immunodeficiency Syndrome↗
PubMed1981

Oestrogen stimulated neurophysin in pregnancy and lactation.

Serum concentrations of oestrogen stimulated neurophysin (ESN) were measured throughout pregnancy in thirty-one women and until 6 weeks post-partum in a further twenty-three. During pregnancy ESN rose progressively and values during labour were similar to those immediately before delivery. There were significant correlations (P less than 0.05) between serum ESN and oestradiol values measured in samples from four patients. After delivery the concentration of ESN fell rapidly to the range for non-pregnant women by 5 days post-partum, whether the mothers lactated or not, and remained fairly constant for the next 6 weeks. Bromocriptine or metoclopramide, drugs which affect prolactin secretion, were without effect on ESN values. At 8 days post-partum in sixteen of the eighteen patients studied there was an increase in ESN concentration 30 min after suckling commenced. At 6 weeks similar changes occurred in five of the ten subjects studied. In contrast, at 8 days there was no significant change in ESN in four mothers who bottle fed their babies over the 90 min studied. The relationship between ESN and hormonal changes during pregnancy and lactation is discussed in the light of these results.

Estradiol↗
PubMed1975

A radioimmunoassay for the estimation of serum dehydroepiandrosterone sulphate in normal and pathological sera.

A radioimmunoassay is described for the measurement of dehydroepiandrosterone sulphate in serum. The method requires 0.1 ml of serum that needs no purification other than a single ether extraction. It is both rapid and economical, procedural losses are small and precision and accuracy are acceptable for both normal and pathological sera. Normal values have been established for children and adults which show a relationship to chronological age, values rising steadily as puberty intevenes, peak values occurring between 20 and 27 years, with a decline thereafter. An empirical curve was fitted to the data and approximate normal limits were obtained. The mean value for pregnanat women in the age range 20-40 years, was statistically significantly lower than in non-pregnant, premenopausal women. The levels of dehydroepiandrosterone sulphate in cord and newborn blood, were higher than at any other time during childhood until signs of puberty were demonstrable. Elevated levels are reported in six patients with untreated congenital adrenal hyperplasia and in one patient with a tumour of the adrenal cortex. It is suggested that this assay provides a useful and precise index of adrenal androgen secretion.

Adolescent↗