Priming and boosting of the rabbit intestinal immune system with live and killed, smooth and rough Vibrio cholerae cells

Cholera disease can be induced in the rabbit by ligation of the cecum (C) followed by duodenal inoculation (DI) of virulent Vibrio cholerae organisms (DIC model). When the cecum is not ligated, DI does not induce disease. In contrast, the animals are primed which becomes apparent upon challenge with live V. cholerae in the DIC model. Such animals are vibriocidally protected. This protection is characterized by absence of disease symptoms, rapid disappearance of V. cholerae from the feces and presence of high levels of anti-lipopolysaccharide Immunoglobulin A in the bile. The present study shows that primed rabbits can also be boosted by duodenal administration of killed, smooth V. cholerae cells. On the other hand, killed cells cannot prime. The minimal lethal dose of a rough derivative of a smooth strain C5, designated R5 and lacking the O antigen part of the LPS, was 100,000 times higher than that of its parent strain C5, in the DIC model. Rabbits which had been duodenally immunized with strain R5 and were subsequently challenged with the smooth strain C5, all developed diarrhea and two out of eight died. This result supports an earlier observation that the specific O antigen part of the V. cholerae LPS is an essential prerequisite for the induction of protective immunity in the rabbit.     

Women's Lives After an HIV-Positive Diagnosis: Disclosure and Violence

Objectives: This research addresses four questions: (1) What role do health care providers play in women's disclosure to others of their HIV-positive status? (2) What are women's concerns and experiences with disclosure? (3) What violence do women living with HIV experience? (4) How is the violence related to their diagnosis and disclosures? Methods: Participants were 310 HIV-positive women enrolled in an HIV primary care clinic in an urban teaching hospital. Women were interviewed once using both quantitative and qualitative methods. Results: Women had known they were HIV-positive for an average of 5.8 years; 22% had an HIV-positive partner; 58% had disclosed their status to more than 10 people; and 68% had experienced physical abuse and 32% sexual abuse as an adult. Fifty-seven percent of the sample reported that a health care provider had told them to disclose to their sex partners. Women who were afraid of disclosure-related violence (29%) were significantly more likely than those who were not to report that a health care provider helped them with disclosure (21% vs. 10%). Although 4% reported physical abuse following a disclosure event, 45% reported experiencing emotional, physical, or sexual abuse at some time after their diagnosis. Risk factors for experiencing abuse after diagnosis were a prior history of abuse, drug use, less income, younger age, length of time since diagnosis, and having a partner whose HIV status was negative or unknown. Conclusions: Identifying women at risk for abuse after an HIV-positive diagnosis is important for those who provide HIV testing and care. Routine screening for interpersonal violence should be incorporated into HIV posttest counseling and continuing primary care services.

     

Sauvagine regulates Ca2+ oscillations and electrical membrane activity of melanotrope cells of Xenopus laevis

Ca2+ oscillations regulate secretion of the hormone alpha-melanphore-stimulating hormone (alpha-MSH) by the neuroendocrine pituitary melanotrope cells of the amphibian Xenopus laevis. These Ca2+ oscillations are built up by discrete increments in the intracellular Ca2+ concentration, the Ca2+ steps, which are generated by electrical membrane bursting firing activity. It has been demonstrated that the patterns of Ca2+ oscillations and kinetics of the Ca2+ steps can be modulated by changing the degree of intracellular Ca2+ buffering. We hypothesized that neurotransmitters known to regulate alpha-MSH secretion also modulate the pattern of Ca2+ oscillations and related electrical membrane activity. In this study, we tested this hypothesis for the secretagogue sauvagine. Using high temporal-resolution Ca2+ imaging, we show that sauvagine modulated the pattern of Ca2+ signalling by increasing the frequency of Ca2+ oscillations and inducing a broadening of the oscillations through its effect on various Ca2+ step parameters. Second, we demonstrate that sauvagine caused a small but significant decrease in K+ currents measured in the whole-cell voltage-clamp, whereas Ca2+ currents remained unchanged. Third, in the cell-attached patch-clamp mode, a stimulatory effect of sauvagine on action current firing was observed. Moreover, sauvagine changed the shape of individual action currents. These results support the hypothesis that the secretagogue sauvagine stimulates the frequency of Ca2+ oscillations in Xenopus melanotropes by altering Ca2+ step parameters, an action that likely is evoked by an inhibition of K+ currents.     

Women's opinions about domestic violence screening and mandatory reporting

BACKGROUND: The purpose of this paper is to describe women's opinions and policy preferences concerning domestic violence screening and mandatory reporting. METHODS: This case-control study included 202 abused women and 240 randomly selected non-abused women recruited from a large metropolitan health maintenance organization who were interviewed by telephone. Of these women, 46.6% had a college degree, 53.4% were white, and 60% had a household income of $50,000 or more. RESULTS: Forty-eight percent of the sample agreed that health care providers should routinely screen all women, with abused women 1.5 times more likely than non-abused women to support this policy. For mandatory reporting, 48% preferred that it be the woman's decision to report abuse to the police. Women thought it would be easier for abused women to get help with routine screening (86%) and mandatory reporting (73%), although concerns were raised about increased risk of abuse with both screening (43%) and reporting (52%) policies. Two thirds of the sample thought women would be less likely to tell their health care providers about abuse under a mandatory reporting policy. Interventions offered in managed care settings that would be well received, according to the women in this study, include counseling services, shelters, and confidential hotlines. CONCLUSIONS: Women expressed fears and concerns about negative consequences of routine screening and, even more so, for mandatory reporting. Domestic violence policies and protocols need to address the safety, autonomy, and confidentiality issues that concern women.     

Cocaine use in pregnancy in Amsterdam

To study the effects of cocaine use in pregnancy in Amsterdam, clinical data on cocaine-using pregnant women ( n = 21) and their offspring ( n = 23) were obtained retrospectively (1987–1994) at the Academic Medical Center, Amsterdam. Infants exposed to cocaine had a median gestational age of 39 weeks and a median birth weight of 3090 g. There were six preterm infants, two small-for-gestational-age infants and five infants with a small head circumference. Three infants had a congenital malformation. One infant (Potter's syndrome) died shortly before birth. One infant had congenital syphilis, four had intracerebral abnormalities on ultrasound and four had abnormal neurologic symptoms in the neonatal period. One infant died after 21 days of life. At follow-up four infants showed abnormal development. In 12 of the 23 infants (52%), one or more possible effects of cocaine were found.