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Biomedical subjects

J A Ford

Publications and source records attributed to J A Ford.

At least 19 recordsLinked to original sources
PubMed2006

Estrogenic effects of genistein on reproductive tissues of ovariectomized gilts.

The soybean phytoestrogen genistein has a range of estrogenic actions demonstrated in various species; however, only limited research has been done to investigate its effects in swine. The objective of this study was to characterize the effects of a graded dose of genistein on estrogen-sensitive uterine and cervical tissues in ovariectomized gilts. Thirty-four postpubertal gilts were ovariectomized and assigned randomly to 1 of 6 treatment groups 15 d postovariectomy. Treatment groups received vehicle, estradiol benzoate (2 mg/d), or genistein (50, 100, 200, or 400 mg/d) via intramuscular injection at 12-h intervals for 10 d. Following the treatment period, gilts were euthanized, and uterine and cervical tissues were collected and processed for chemical or histological analysis. Uterine and cervical tissue mass, as indicated by wet, dry, and protein weights and total DNA content (expressed per 100 kg of BW), increased as the dosage of genistein increased (P < 0.001 for each regression). Uterine and cervical wet weights were increased by a dosage of 200 mg of genistein/d (P < 0.001 and P < 0.01, respectively) but not by 100 mg of genistein/d (P = 0.38 and P = 0.14, respectively) compared with those of control gilts. Height of epithelial cells lining the uterine glands and the lumen of uterus and cervix increased when gilts were treated with estradiol benzoate or 400 mg of genistein/d (P < 0.01). When the gilts were treated with estradiol benzoate or 400 mg of genistein/d, immunohistochemical staining demonstrated an increase in the percentage of cells that stained positive for progesterone receptor in the uterine glands and in the cells lining the vaginal cervix (P < 0.05). In gilts treated with 400 mg of genistein/d, the percentage of cells stained positive for proliferating cell nuclear antigen increased in the epithelium of the uterine glands, uterine lumen, and vaginal cervix (P < 0.05). Tissue growth was stimulated by genistein in a dosage-dependent manner, although no dosage of genistein induced a response as great as that of estradiol benzoate. Estrogen-sensitive tissues of the ovariectomized gilt, such as the cervix and uterus, are affected by injection of large dosages of the phytoestrogen genistein. The sensitivity of the uterus of the gilt to estrogenic substances makes it a potential model to examine the impact of environmental endocrine modulators on reproductive tissues.

Animals↗
PubMed2003

Quantification of mammary gland tissue size and composition changes after weaning in sows.

The objectives of this study were to characterize the tissue compositional changes in porcine mammary glands after weaning and to determine whether administration of estradiol alters the profile of these tissue changes. Forty-five primiparous sows were assigned randomly to one of two treatment groups after weaning, control or estrogen treated. Estrogen-treated sows received twice-daily injections of estradiol-17beta (0.125 mg/kg of BW); control sows received vehicle injections. Sows were weaned at d 21 of lactation and killed on either d 0 (d of weaning; n = 5) or on d 2, 3, 4, 5, or 7 after weaning (n = 4 per treatment on each day). Teat order relative to suckling behavior was observed on the day before weaning to determine which mammary glands the piglets suckled. Suckled and non-suckled glands were identified from the teat order observation, and individual mammary glands were collected at slaughter. Mammary glands were trimmed of skin and extraneous fat pad, individually weighed, and bisected to measure cross-sectional area. The remaining half of each gland was ground and stored at -20 degrees C for chemical analyses. Frozen tissue was used for measuring tissue DNA, DM, protein, fat, and ash contents. Suckled mammary glands of sows undergo significant and dramatic changes during the initial 7 d after weaning, with significant changes occurring even by d 2 after weaning. Mean cross-sectional area of parenchymal tissue in suckled mammary glands decreased from 59.7 +/- 2.1 cm2 on the day of weaning to 26.8 +/- 2.3 cm2 by d 7 after weaning (P < 0.0001). Mammary gland wet weight decreased from 485.9 +/- 22.0 g on the day of weaning to 151.5 +/- 24.8 g by d 7 after weaning (P < 0.0001), whereas DNA decreased from 838.8 +/- 46.2 g on the day of weaning to 278.4 +/- 52.5 g by d 7 after weaning (P < 0.0001). The changes in gland wet weight and DNA during the period of mammary gland involution in the sow represent loses of over two-thirds of the parenchymal mass and nearly two-thirds of the cells that were present on the day of weaning. Estrogen treatment did not affect overall mammary involution during the first 7 d after weaning. Mammary glands that were not suckled during lactation had no further loss of parenchymal tissue during the first 7 d after weaning. Mammary gland involution in the sow is a rapid process and is probably irreversible within 2 or 3 d after weaning.

Animals↗
PubMed2001

Drinking patterns among Hispanic adolescents: results from a national household survey.

OBJECTIVE: This is one of the first studies to examine and compare alcohol use for adolescent Cubans, Mexican Americans, Puerto Ricans and other Hispanics. METHOD: The data come from the 1993 National Household Survey on Drug Abuse (NHSDA), a national probability sample of the U.S. household population. The sample examined here (N = 1,865, 52% male) comprises 200 Cubans, 1,133 Mexican Americans, 255 Puerto Ricans and 277 Central/South Americans who were 12 to 17 years old. Drinking patterns are measured using a quantity-frequency index, and analyses are conducted using Stata. RESULTS: In the cross-tabulations, no ethnic differences in drinking patterns are found for males or females, nor is there evidence of gender differences within ethnic groups, although there are some age differences in alcohol use. In the logistic regression analyses, two ethnic differences emerge, although the factors most consistently associated with drinking behaviors in these analyses are age, Spanish language use and urban residence. Additional analyses using the 1998 NHSDA suggest that ethnic differences in alcohol use may emerge in late adolescence/early adulthood. CONCLUSIONS: Given the established findings of ethnic and gender differences in drinking among adult Hispanics, it is surprising that few differences are evidenced in adolescence. Future research should explore whether such differences emerge during the transition into adulthood and, if so, identify factors that produce them. In addition, to increase understanding of these ethnic groups' drinking patterns, future research should further investigate the factors associated with Hispanic adolescents' alcohol use, including both consideration of whether the predictors are the same across groups and of the role of sociocultural factors.

Acculturation↗
PubMed2001

Nutritionally directed compensatory growth enhances heifer development and lactation potential.

The objectives of this study were 1) to examine the interactive influence of a compensatory nutrition regimen and lasalocid supplementation on dairy heifer growth performance and 2) to document the extent to which compensatory growth sustains lactation potential over the first two lactation cycles. Twelve Holstein heifers, weighing an average of 160 kg (about 6 mo of age) were randomly assigned to treatments arranged in a 2 x 2 factorial design. Treatment variables were two dietary regimens (control and stair-step compensatory nutrition) and two levels of lasalocid (0 and 200 mg/d). The control heifers were fed a diet containing 12% crude protein (CP) and 2.35 Mcal of metabolizable energy (ME) per kilogram of dry matter. The stair-step compensatory nutrition heifers were subjected to a phased nutrition regimen and reared according to an alternating 3-2-4-3-4-2-mo schedule. The first stair-step (prepubertal phase) consisted of energy restriction [17% CP and 2.35 Mcal/kg of ME] for 3 mo followed by realimentation (12% CP and 3.05 Mcal/kg of ME) for 2 mo. The second step (puberty and breeding) consisted of energy restriction for 4 mo followed by realimentation for 3 mo. The third step (gestation period) was energy restriction for 4 mo concluding with realimentation for 2 mo. Dry matter intake of heifers during the restriction phase was limited to 70% of the control intake. Heifers were given ad libitum access to a high energy density diet during realimentation to allow compensatory development. Stair-step heifers supplemented with lasalocid had the highest efficiency of growth (body weight gain/dry matter intake), suggesting synergistic metabolism of lasalocid with compensatory growth action. Compensatory growth induced during the last trimester enhanced metabolic status by increasing circulating insulin and decreasing triglyceride levels. Heifers on the stair-step regimen had a significant increase in milk yield during the first (21%) and second (15%) lactation cycles. These results support our thesis that compensatory growth induced during an allometric growth phase improves mammary development and energy and protein metabolic status of dairy heifers.

Age Factors↗
PubMed1999

Under the influence: risky sexual behavior and substance abuse among driving under the influence offenders.

BACKGROUND AND OBJECTIVES: The purpose of this study was to examine the associations between alcohol and drug abuse and risky sexual practice in a sample of 366 driving under the influence (DUI) offenders. STUDY DESIGN: Data were collected from a sample of participants at a university-operated drunk driving intervention program. Specific indicators included established or severe alcohol/drug use problems, multiple drugs used, multiple alcohol/drug related arrests, and early regular alcohol use. Multiple sexual partners, condom use, and having sex while under the influence of alcohol or drugs were used to measure risky sexual behavior patterns. Correlation and logistic regression analyses examined associations between these substance abuse and sexual risk taking measures. RESULTS: Substance abuse in general was unrelated to risky sexual behavior such as multiple sexual partners or lack of condom use. However, having sex while high from alcohol or drugs was significantly associated with substance abuse. Moreover, having sex while high was significantly related to both risky sex and a history of sexually transmitted disease. CONCLUSIONS: Having sex while high may be an important behavior to address to prevent STDs in the DUI population. Assessing relationships between substance abuse and risky sexual behavior poses a challenge to researchers because any estimates about this association may be dependent on the measure of sexual behavior that is used. An integrated intervention approach that addresses both substance abuse prevention and safe sexual practice appears crucial and effective for educating "risk takers" such as DUI offenders. However, these data caution that for those who are dependent upon alcohol and/or other drugs, education solely emphasizing risk reduction procedures is likely to be inefficient until their chemical dependency is addressed.

Adult↗
PubMed1998

Illicit drug use by women with disabilities.

As in the general female population, women with disabilities face a number of situations that encourage illicit drug use, such as low self-esteem, peer pressure, and family history of substance abuse. In addition, women with disabilities more frequently encounter problems of personal adjustment, unusual developmental experiences, easy access to prescription drugs, unemployment, and medical or health-related difficulties. Using a random sample of 900 women with disabilities, we conducted a study of the patterns of illicit drug use and risk factors relating to illicit drug use among women with various disabilities. Multiple regression analyses revealed that age, illicit drug use by a best friend, being a victim of substance-abuse-related violence, and attitudes toward substance use by people with disabilities were significantly related to illicit drug use by the study population. The implications of these findings are discussed.

Adult↗
PubMed1996

Late acute rejection occurring in liver allograft recipients.

To study the effect of immunosuppressive reduction on the incidence and consequence of late acute rejection (LAR) in liver allograft recipients, mean daily prednisone dose, mean cyclosporine A (CsA) trough and nadir levels were retrospectively reviewed for the nearest 12-week period preceding six episodes of LAR in five liver allograft recipients (group 1). Results were compared with those from a cohort of 12 liver allograft recipients who did not develop LAR (group 2). LAR was defined as acute rejection occurring more than 365 days post-transplantation. Median follow-up for both groups was similar (504 days, range 367 to 1050, versus 511 days, range 365 to 666, not significant). Mean trough CsA levels were lower in patients with LAR compared with those without (224 +/- 66 ng/mL versus 233 +/- 49 ng/mL) but the difference was not statistically significant. In contrast, mean daily prednisone dose (2.5 +/- 1.6 mg/day versus 6.5 +/- 2.9 mg/day, P = 0.007) and CsA nadir values (129 +/- 60 ng/mL versus 186 +/- 40 ng/mL, P = 0.03) were significantly lower in patients who developed LAR compared with those who did not. Five of six episodes (83%) of LAR occurred in patients receiving less than 5 mg/day of prednisone, versus a single LAR episode in only one of 12 patients (8%) receiving prednisone 5 mg/day or more (P = 0.004). In all but one instance, LAR responded to pulse methylprednisolone without discernible affect on long term graft function. The authors conclude that liver allograft recipients remain vulnerable to acute rejection beyond the first post-transplant year; and reduction of immunosuppressive therapy, particularly prednisone, below a critical, albeit low dose, threshold increases the risk of LAR.

Acute Disease↗
PubMed1981

Policy for prevention of Asian rickets in Britain: a preliminary assessment of the Glasgow rickets campaign.

Evidence of continuing hospital admissions of patients with Asian rickets and osteomalacia led to a further attempt to provide more effective preventive measures for the Glasgow Asian community. Dose-response studies showed that the equivalent of 10 microgram of vitamin D daily would provide effective prophylaxis, and a general practice survey showed that self-administered vitamin D supplements would reduce the prevalence and severity of Asian rickets. A multidisciplinary working group devised a preventive campaign based on the free issue of vitamin D supplements on demand to children who required them. Supported by a health education programme for community health personnel and the Asian community, the first 16 months of the campaign produced an eight-fold rise in the issue of supplements to older Asian children and a 33% increase in their issue to infants of all ethnic groups. Because more children are receiving vitamin D supplementation the campaign seems likely to reduce the prevalence of Asian rickets in Glasgow.

Adolescent↗
PubMed1981

The role of cereals in the aetiology of nutritional rickets: the lesson of the Irish National Nutrition Survey 1943-8.

1. Review of the evidence of the Irish Nutrition Survey concerning a market rise in the incidence of rickets in Dublin in 1942 concludes that a rise in the extraction rate of the national flour from 70 to 100% was principally responsible. 2. This rise and subsequent decrease in incidence as the extraction rate of flour was reduced is not explained by changes in the proportion of children protected by vitamin D supplements or by small changes in dietary vitamin D intake. 3. The evidence suggests that nutritional rickets in man cannot be explained on the basis of deficient vitamin D intake alone, whether derived from diet or u.v. radiation.

Aged↗
PubMed1980

The insulin response to intravenous fructose in maturity-onset diabetes mellitus and in normal subjects.

Insulin responses to intravenous fructose and glucose were measured in 15 patients with maturity-onset diabetes mellitus. In eight patients given fructose first the insulin responses to fructose and glucose were similar. In seven patients given glucose first the insulin response to subsequently infused fructose was significantly greater than to glucose. Multiple regression analysis showed that the ratio of the fructose to glucose insulin response, assessed by area under the insulin serum concentration-time curve (F/G ratio) in individual patients, correlated most closely with prefructose infusion plasma glucose. Similar analysis, applied to results in 27 normal subjects, showed that the most important determinant of the insulin response to fructose in this group also was the immediate prefructose infusion plasma glucose. Thus in diabetics, as in normal controls, the response of the beta cell to intravenous fructose appears to be sensitively set by the ambient plasma glucose concentration at the onset of fructose infusion.

Adult↗
PubMed1979

Natural history of placenta previa ascertained by diagnostic ultrasound.

Placental localization by diagnostic ultrasound was performed at 16 to 18 weeks' gestation in 1,098 patients prior to amniocentesis for genetic indications. Placenta previa was diagnosed in 58 patients, 47 of whom went on to delivery uncomplicated by placenta previa. There were five patients with placenta previa at delivery, four of whom had third-trimester bleeding. One patient was diagnosed as having a normal placental implantation at midtrimester but placenta previa was demonstrated at delivery. The incidence of placenta previa at 16 to 18 weeks' was 5.3% and fell to 0.58% at delivery, indicating a 90% conversion rate. Thus the vast majority of cases of asymptomatic placenta previa remain so and convert before delivery. These patients should be observed with serial ultrasound at 6 to 8 week intervals until delivery or unequivocal conversion. No restriction in activity seems indicated unless the placenta previa persists beyond 30 weeks or becomes clinically manifest.

Adult↗
PubMed1979

Amniotic fluid lecithin/sphingomyelin ratio, palmitic acid, palmitic acid/stearic acid ratio, total cortisol, creatinine, and percentage of lipid-positive cells in assessment of fetal maturity and fetal pulmonary maturity: a comparison.

Lecithin/sphingomyelin (L/S) ratio, creatinine, percentage of lipid-positive cells, palmitic acid, palmitic acid/stearic acid (P/S) ratio, and total cortisol were analyzed as tests for fetal maturity and fetal pulmonary maturity in 164 samples of amniotic fluid from 121 patients. Fifty samples were taken within 72 hours of delivery. The best tests for fetal maturity (37 weeks) with differential percentages were L/S ratio, palmitic acid, and P/S ratio. In the assessment of fetal pulmonary maturity, we studied an additional 174 samples in which only L/S ratio, creatinine, and lipid-positive cells were analyzed. All tests showed a high predictive value of an immature (positive) result was much less for all six parameters; the three best tests were total cortisol (33%), lipid-positive cells (26%) and L/S ratio (14%).

Amniotic Fluid↗