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Biomedical subjects

C Williams

Publications and source records attributed to C Williams.

At least 271 records · Page 15Linked to original sources
PubMed1997

Effect of milk-borne epidermal growth factor on the hepatic microcirculation and Kupffer cell function in suckling rats.

Epidermal growth factor (EGF) is contained in breast milk, is transported intact across the gastrointestinal mucosa during the suckling period, retains its biological activity, and affects hepatic growth. Whether or not EGF also influences postnatal hepatic development by affecting nonparenchymal cells or by modifying intrahepatic blood is not clear. As a result, the effect of EGF on the hepatic microvasculature was studied in suckling rats fed rat milk substitute (RMS) with and without EGF (100 ng/ml, i.e. twice the normal intake in breast milk) between days 11 and 14 and compared to pups breast-fed for 14 days. The livers of anesthetized pups were examined by in vivo microscopy to determine the numbers of sinusoids with flow (SCF) in each of 10 microscopic fields and the numbers of phagocytic Kupffer cells (KC) in the same fields following an intraportal injection of fluorescent 1-micron latex particles. Phagocytic activity was expressed as the ratio KC/SCF. In pups fed RMS without EGF, SCF and KC/SCF was 75 and 45%, respectively, of that in breast-fed animals. The addition of EGF to the RMS restored SCF and KC/SCF nearly to the levels measured in breast-fed pups. Thus, the results suggest that milk-borne EGF plays a role in the development of KC phagocytic function and affects the amount of blood that perfuses the sinusoidal bed in the suckling.

Animals↗
PubMed1997

Psychiatric dilemmas--surgery and the Mental Health Act (1983).

Clinicians commonly face an ethical conundrum when the patient declines a treatment they believe to be necessary. The decision, whether to give or to withhold treatment, may also have legal repercussions. Two illustrative cases are presented. Although the Mental Health Act (1983) is concerned with treatment of mental disorder, treatments for physical disorders may be given in certain circumstances if the patient is deemed to lack the competence to understand the issues involved in the decision, and treatment is deemed to be in their best interests.

Adult↗
PubMed1997

Variations in pigment and carbohydrate content of gallbladder bile affect accurate quantitation of total protein when using the fluorescamine method.

BACKGROUND: Despite solute dilution and reduced total lipid concentrations, an unexplained increase in protein concentration has been reported to occur in the gallbladder bile of cholesterol gallstone patients. METHODS: Solutes in gallbladder bile from gallstone-free controls and from four study groups were measured using standard methods. Total proteins were measured using amino acid analysis and a conventional fluorescamine method. RESULTS: Bile salts and pigment content were greater in gallstone-free controls than in all other study groups, including morbidly obese gallstone-free subjects. Total biliary protein concentration, as determined by amino acid analysis in the gallstone-free control group was higher than in non-obese gallstone patients with multiple stones and in morbidly obese gallstone-free subjects. Total biliary proteins as measured with fluorescamine, however, did not show intergroup differences. A major problem of the conventional fluorescamine assay is shown to be an artefact arising from the high pigment content of the more concentrated samples. CONCLUSIONS: Very dilute gallbladder bile samples are often found in the presence of gallstone disease. This also occurs in morbidly obese subjects, even in the absence of gallstones. Although the contribution of protein secretion/absorption by the gallbladder can also be relevant, especially in the presence of morbid obesity, the protein concentration in gallbladder bile, when accurately measured, generally parallels the concentrations of non-absorbed biliary solutes, reflecting the efficiency of fluid absorption. Measurement of biliary proteins by the conventional fluorescamine method is unreliable in clinical studies in which intergroup differences in pigment content are commonly present.

Adult↗
PubMed1997

Differences in physician compensation for cardiovascular services by age, sex, and race.

The purpose was to determine whether physicians receive substantially less compensation from patient groups (women, older patients, and nonwhite patients) that are reported to have low rates of utilization of cardiovascular services. Over an 18-month period we collected information on payments to physicians by 3,194 consecutive patients who underwent stress testing an 833 consecutive patients who underwent percutaneous coronary angioplasty at the Yale University Cardiology Practice. Although the charges for procedures were not related to patient characteristics, there were large and significant differences in payment to physicians based on age, sex, and race. For example, physicians who performed percutaneous transluminal coronary angioplasty received at least $2,500 from, or on behalf of, 72% of the patients 40 to 64 years old, 22% of the patients 65 to 74 years old, and 3% of the patients 75 years and older (P < 0.001); from 49% of the men and 28% of the women (P < 0.001); and 42% of the whites and 31% of the nonwhites (P < 0.001). Similar differences were observed for stress testing. These associations were largely explained by differences in insurance status.

Age Factors↗
PubMed1997

Clinical efficacy of an optimized stannous fluoride dentifrice, Part 3: A 6-month plaque/gingivitis clinical study, southeast USA.

This 6-month, double-blind clinical study, also following the American Dental Association guidelines, investigated the efficacy of Colgate Optimized Stannous Fluoride (COSF) dentifrice in controlling supragingival dental plaque and gingivitis. The same dentifrice, containing 0.454% stannous fluoride, stannous chloride, polyphosphate, and citrate in a silica base was used. Adult men and women from the Atlanta, Georgia, area received an oral prophylaxis and were instructed to brush their teeth twice daily (morning and evening) for 1 minute with their assigned dentifrice, using a soft-bristled toothbrush. As in the first study, plaque and gingivitis examinations were conducted after 3 months and again after 6 months of using the dentifrices. At both the 3- and 6-month study examinations, the COSF dentifrice group exhibited statistically significant reductions in both plaque and gingivitis compared to the control dentifrice group. At the 6-month examination, the magnitude of these percent reductions exceeded 20% for all 4 parameters measured. Thus, the results of this study reflect those found in the New Jersey study, i.e., supporting the conclusion that the COSF dentifrice is efficacious for the control of supragingival plaque and gingivitis.

Adolescent↗
PubMed1997

Wound-measuring methods.

Measurement of a wound is an integral part of the overall holistic wound assessment. Wound assessment is essential for effective wound management. Wound measurement can be described as either contact or non-contact. Many measurements are subjective but remain a useful and practical indication of wound healing. For many community and hospital nurses the best method is tracing, to measure area in conjunction with a depth gauge.

Humans↗
PubMed1996

The role of the cyclic AMP-responsive element binding protein (CREB) in hypoxic-ischemic brain damage and repair.

The cyclic AMP-responsive element binding protein (CREB) is a basally expressed, post-translationally activated transcription factor that has been implicated in the trans-activation of a number of genes in response to cAMP and calcium signals. A unilateral hypoxic-ischemic (HI) injury in the 21 day old rat was used to examine a potential role for CREB (phosphorylated and unphosphorylated) in neuronal programmed cell death or cell survival. The selectively vulnerable CAI pyramidal cells, which undergo delayed neuronal death following mild HI, show a loss of CREB and phosphorylated CREB (pCREB) immunoreactivity on the injured side 48 and 72 h following HI. In contrast the resistant dentate granule cells and cortical cells produce a bimodal increase in pCREB immunoreactivity, peaking 6 and 48 h following HI. The fact that cells surviving the HI insult are showing increased activation of CREB suggests that this protein might be involved in the process of neuroprotection.

Animals↗
PubMed1996

Teaching of human rights in US medical schools.

OBJECTIVE: To determine the extent to which human rights issues are included in required bioethics curricula in US medical schools and to identify medical school characteristics associated with the extent of human rights issues covered. DESIGN: Cross-sectional survey. PARTICIPANTS: Bioethics course directors and bioethics section directors of 125 US medical schools. MAIN OUTCOME MEASURE: The extent of human rights teaching at each school was measured as the percentage of 16 human rights issues. RESULTS: Course directors at 113 (90%) of the 125 US medical schools responded to the survey. Medical schools included about half (45%; 95% confidence interval, 41%-49%) of 16 human rights issues in their required bioethics curricula. Domestic human rights issues, such as discrimination in the provision of health care to minorities (82% of medical schools), were covered much more frequently than international human rights issues, such as physician participation in torture (17% of schools). Public medical schools included substantially fewer human rights issues than private medical schools (F[1,112]=7.7; P<.01). CONCLUSIONS: Required courses in medical education do not adequately address the medical aspects of human rights issues, especially international issues.

Analysis of Variance↗
PubMed1996

A mutation that allows endosperm development without fertilization.

The mechanisms that initiate reproductive development after fertilization are not understood. Reproduction in higher plants is unique because it is initiated by two fertilization events in the haploid female gametophyte. One sperm nucleus fertilizes the egg to form the embryo. A second sperm nucleus fertilizes the central cell to form the endosperm, a unique tissue that supports the growth of the embryo. Fertilization also activates maternal tissue differentiation, the ovule integuments form the seed coat, and the ovary forms the fruit. To investigate mechanisms that initiate reproductive development, a female-gametophytic mutation termed fie (fertilization-independent endosperm) has been isolated in Arabidopsis. The fie mutation specifically affects the central cell, allowing for replication of the central cell nucleus and endosperm development without fertilization. The fie mutation does not appear to affect the egg cell, suggesting that the processes that control the initiation of embryogenesis and endosperm development are different. FIE/fie seed coat and fruit undergo fertilization-independent differentiation, which shows that the fie female gametophyte is the source of signals that activates sporophytic fruit and seed coat development. The mutant fie allele is not transmitted by the female gametophyte. Inheritance of the mutant fie allele by the female gametophyte results in embryo abortion, even when the pollen bears the wild-type FIE allele. Thus, FIE carries out a novel, essential function for female reproductive development.

Journal Article↗
PubMed1996

Older adults. An 11-year longitudinal study of adult protective service use.

BACKGROUND: Little is known about the epidemiology of adult protective services agency (APS) utilization, the state entities charged with assessment and advocacy for disenfranchised older adults. OBJECTIVE: To determine the prevalence of utilization by older adults and risk factors for APS. METHODS: A longitudinal study using the New Haven Established Population for Epidemiologic Studies in the Elderly population, a cohort of 2812 community-dwelling adults who were older than 65 years in 1982. The main outcome measure was referral to the state ombudsman on aging for protective services. RESULTS: Over the 11-year follow-up period, 209 cohort members (7.4%) were referred to the ombudsman 302 times as protective service cases for a community prevalence of 6.4% after adjusting for the sampling strategy of the cohort. Self-neglect was the most common indication for referral (73% of the cases). While in bivariate analyses a variety of baseline sociodemographic features, functional impairments, medical conditions, and social network factors were associated with APS use, in multivariable analysis only sociodemographic variables remained independent risk factors including low income (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.8 to 3.9), nonwhite race (OR, 2.2; 95% CI, 1.3 to 3.7), and age older than 75 years at cohort inception (OR, 1.9; 95% CI, 1.1 to 3.0). CONCLUSIONS: Prevalence of APS use by older adults is substantial, and sociodemographic features were the most compelling risk factors in our cohort. As the population ages, the number of older adults at risk for abuse, neglect, self-neglect, exploitation, and abandonment will increase; physicians will need to become familiar with APS referral pathways and mandatory reporting laws in their states.

Aged↗