Efficiency of epidural blood patches in the obstetrics.
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Biomedical subjects
Publications and source records attributed to E Williams.
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This article describes the preliminary experimental steps and clinical implementation of a purely pediatric liver transplantation (LT) program in a large public children's hospital in Buenos Aires, Argentina, a city with well over 10 million inhabitants and a referral population of over 30 million. Between 1993 and 1997, 84 LTs were performed in 81 patients, of which one-fourth weighed below 10 kg. The main indications were biliary atresia (n = 25, 30%) and fulminant liver failure (n = 23, 27%), followed by autoimmune cirrhosis (n = 14, 16%) and other liver diseases. Shortage of organs due to local conditions led to the use of liver-reduction techniques in 48 cases (57%), split liver in 2, and living-related donor (LRD) in 2. Retransplantation was necessary in 3 instances. Seventy-eight percent of the recipients survived for more than 1 year and 71% were alive after 4 years. The authors comment on the need for adaptation to local conditioning factors when developing a pediatric LT program in any country in which demographics and economic, medical, and sociological environments have a decisive influence on organ procurement, the actual performance of the operation, and the lifelong postoperative medication. In Buenos Aires, where the hospital setting is well-developed, the indications are in part determined by the high incidence of hepatitis A. Organ shortages in our area led to liberal use of liver reduction, split-liver, and LRD techniques. The overall results of the first years of such a program were largely satisfactory.
Artificial insemination with motile spermatozoa prepared from HIV-infected men using standard procedures has been employed with many HIV-discordant couples. We have demonstrated that processing semen from HIV positive men can reduce HIV levels, measured as HIV1 RNA copies/ml using nucleic acid based sequence amplification (NASBA), to undetectable levels (less than 400 copies/ml) but not in all samples. We believe that all processed samples should be tested prior to insemination.
Conservative surgical options for uterine myomata traditionally were abdominal myomectomy, laparoscopic myomectomy, and, more recently, myolysis. Each of these procedures has distinct advantages, but also apparent disadvantages. We attempted to introduce an additional option for conservative surgical treatment of fibroids by freezing the structures, a procedure termed cryomyolysis. In this pilot study, 14 women were pretreated with a gonadotropin-releasing hormone (GnRH) agonist for a minimum of 2 months preoperatively to minimize uterine and myoma size. Cryomyolysis was performed and the GnRH agonist was discontinued. Magnetic resonance imaging scans were performed in 10 of the 14 women after GnRH agonist treatment but before surgery, and 4 months postoperatively. Total uterine volume ranged from 41.3 to 1134.8 ml preoperatively, and 49.5 to 1320 ml postoperatively (mean increase 22% after discontinuation of GnRH agonist). Normal uterine volume ranged from 35.6 to 548.7 ml preoperatively and 45.1 to 729.6 ml postoperatively (mean increase 40%); however, myoma volume showed a mean decrease of 6% (range -87-28%). Analysis of only frozen myomata revealed a mean volume decrease of 10%. Cryomyolysis maintains at or slightly reduces these lesions to post-GnRH agonist size, and all other uterine tissue returns to pretreatment size. We believe cryomyolysis may be an effective conservative surgical approach to uterine fibroids.
This randomized controlled trial evaluated the efficacy of a brief intervention designed to reduce the harmful consequences of heavy drinking among high-risk college students. Students screened for risk while in their senior year of high school (188 women and 160 men) were randomly assigned to receive an individualized motivational brief intervention in their freshman year of college or to a no-treatment control condition. A normative group selected from the entire screening pool provided a natural history comparison. Follow-up assessments over a 2-year period showed significant reductions in both drinking rates and harmful consequences, favoring students receiving the intervention. Although high-risk students continued to experience more alcohol problems than the natural history comparison group over the 2-year period, most showed a decline in problems over time, suggesting a developmental maturational effect.
Recent advances in AIDS treatment have brought renewed optimism for prolonging the lives of those infected with HIV. This article examined beliefs about how new treatments may reduce HIV transmission risk among 298 HIV-negative gay and bisexual men attending a gay pride festival. Results from an anonymous survey showed that men who practiced unprotected anal intercourse as the receptive partner (UAR intercourse) were younger, less well educated, and more likely to believe that it is safe to have UAR intercourse with an HIV-positive man who has an undetectable viral load and that new treatments for HIV relieve their worries about unsafe sex. As HIV treatments continue to advance, new challenges for HIV prevention will likely emerge.
UNLABELLED: Amrinone and milrinone are phosphodiesterase inhibitors with positive inotropic effects useful for the treatment of ventricular dysfunction after cardiac surgery. Forty-four patients undergoing elective cardiac surgery at four centers received either amrinone (n = 22) or milrinone (n = 22) in a randomized, blind fashion. Immediately after separation from cardiopulmonary bypass (CPB), two bolus doses of either amrinone 0.75 mg/kg or milrinone 25 microg/kg were administered over 30 s, separated by 5 min. Hemodynamic measurements were recorded before each dose and at the end of the 10-min study. Both amrinone and milrinone increased the cardiac index (48% vs 52%, P = not significant [NS] for amrinone and milrinone, respectively). There was a small increase in mean arterial pressure (MAP) after amrinone administration (from 68 +/- 3 to 72 +/- 3 mm Hg at 10 min, P < 0.05) with no significant change in MAP after milrinone administration. Central venous pressure was significantly higher in the amrinone group at baseline and 5 min (12 vs 10 mm Hg and 11 vs 10 mm Hg, respectively; P < 0.05). Systemic and pulmonary vascular resistances decreased significantly and to a similar extent after either amrinone or milrinone administration. Phenylephrine was required in 11 of 22 patients receiving amrinone and in 11 of 22 patients receiving milrinone to maintain arterial blood pressure. The proportion of patients requiring an intravascular volume infusion (15 of 22 vs 17 of 22, P = NS) and the total fluid volume infused were similar (402 +/- 57 vs 350 +/- 49 mL, P = NS for amrinone and milrinone, respectively). Amrinone and milrinone seem to have similar hemodynamic effects after CPB, with the exception of blood pressure, although the need for vasopressor support of blood pressure did not differ. Selection between these two drugs may include nonhemodynamic considerations such as cost. IMPLICATIONS: Amrinone and milrinone are drugs that improve cardiac contraction. Their effects have never been directly compared in patients. We found that amrinone and milrinone produced similar hemodynamic effects in adult patients undergoing cardiac surgery. Choice between the two drugs can be based on nonhemodynamic considerations such as cost.
Four moderately thermophilic, carboxydotrophic streptomycetes were the subject of a comparative taxonomic investigation designed to establish their taxonomic relationships. Almost complete sequences of the 16S rRNA genes of the test strains were determined following the isolation and direct sequencing of the amplified genes. The resultant nucleotide sequences were aligned with the sequences of previously studied streptomycetes, and phylogenetic trees generated by using the neighbour-joining, Fitch-Margoliash, maximum-likelihood and maximum-parsimony methods. It was evident from the phylogenetic analyses that strains AT50, AT51 and AT52 were most closely related to Streptomyces thermodiastaticus DSM 40573T and strain AT37 to Streptomyces glaucescens DSM 40716 and Streptomyces pseudogriseolus NRRL 3985. Random DNA amplification profiles clearly distinguished strains AT50, AT51 and AT52 from Streptomyces thermodiastaticus and from strain AT37. The molecular systematic evidence, together with phenotypic data derived from this and previous studies, indicate that the test strains merit species status within the genus Streptomyces. The name Streptomyces thermocarboxydovorans sp. nov. is proposed for strains AT50, AT51 and AT52 (type strain) and Streptomyces thermocarboxydus sp. nov. for strain AT37.
It has been proposed that teenage girls often smoke cigarettes to protect themselves from the impulse to binge eat, with its feared weight-gain consequences, particularly when other measures such as greater dietary restraint have failed. The present study looked at the relationship between body mass index and standardised questionnaire responses concerning smoking, alcohol consumption, moods, weight changes, attitudes to body weight and shape, dietary patterns and menstruation in 1936 British (London) and 832 Canadian (Ottawa) schoolgirls. Data analysis revealed links between cigarette smoking and body weight/shape concerns, and awareness by subjects of these links; there was also a tendency for smokers in these two populations to be overweight but not grossly obese. Smoking was also related at all ages to being postmenarchal. The London population in particular revealed an association between smoking and a weight loss of 7 kg or more at some stage since puberty. Smoking was also linked, in a minority, with regular vomiting undertaken as a further defence against weight gain when overeating had occurred. These associations existed alongside the major and predictable association found between alcohol consumption and smoking. Similarities between the British and Canadian schoolgirls were striking in respect of rank order of reasons given for smoking and consequences of giving it up. Since smoking amongst older women is reportedly associated with below-average body weight it may indeed be effective in helping to curb weight gain. Our study provided little evidence of association between smoking and generalised anxiety or social anxiety (in either population), or depression (in the British cohort). We suggest that any preventive psychological approach to teenage female smoking should include attention to weight gain anxiety and consequent pursuit of thinness.
BACKGROUND: Despite the growing belief that "the community" should play a larger role in the work of physicians, there is no clear understanding of exactly how physicians should participate in their communities. The primary goals of this study were to propose and test an organizing framework that identified four distinct categories of activities whereby physicians can interact with their communities: (1) identifying and intervening in the community's health problems; (2) responding to the particular health issues of local cultural groups when caring for patients; (3) coordinating local community health resources in the care of patients; and (4) assimilating into the community and its organizations. Other goals were to characterize physicians' level of involvement in each of these four types of community activities, and to identify the correlates of greater and lesser involvement. METHODS: A questionnaire was mailed to a random sample of 500 young primary care physicians in the United States. The response rate was 66.6%. Physicians reported how confident they were in performing each of 15 specific community-relevant activities. Confidence ratings were factor-analyzed to test the hypothesis that physician involvement in community activities can be organized into the four proposed categories. Physicians also self-rated their involvement in various community activities within each of these four categories, and predictors of involvement were identified through ordinary least-squares regression models. RESULTS: Using factor analysis, the community activities sorted cleanly into the four postulated community dimensions of medical practice, providing a measure of validation for the distinctiveness of the four dimensions. Physicians reported active involvement in some activities (eg, speaking to community groups and gaining acceptance in their communities) and little involvement in other activities (eg, working with community groups to address local health problems, familiarity with local women's shelters). Contrary to expectations, physicians who worked with minority and poorer patient populations and counties generally reported less community involvement. Physicians caring for more patients covered by HMO or capitated health insurance plans also reported lower participation in their communities. CONCLUSIONS: This study provides support for the hypothesis that the community plays a role in the work of physicians that can be categorized into four types of activities. This framework may help physicians and practices recognize the breadth of ways they can meet the growing demand that they approach their work with a community perspective.
A case of angiomyofibroblastoma of the vulva in a 23-year-old woman is presented. Clinical, histological and immunohistochemical features as well as the differential diagnosis and prognosis of this rare but distinct entity are discussed. Only about 65 cases are documented in the literature and to our knowledge this is the first case to be reported from the Caribbean.
OBJECTIVE: To assess the impact of the comprehensive HIV/STD Control Program established in Jamaica since the late 1980s on the HIV/AIDS epidemic. METHODS: AIDS case reports, HIV testing of blood donors, antenatal clinic attenders (ANC), food service workers, sexually transmitted disease (STD) clinic attenders, female prostitutes, homosexuals and other groups were used to monitor the HIV/AIDS epidemic. Primary and secondary syphilis and cases of congenital syphilis were also monitored. National knowledge, attitude and practice (KAP) surveys were conducted in 1988, 1989, 1992, 1994 and 1996. RESULTS: The annual AIDS incidence rate in Jamaica increased only marginally in the past three years from 18.5 per 100000 population to 21.4 in 1997. HIV prevalence in the general population groups tested has been about 1% or less. Among those at high risk, HIV prevalence rates have risen to 6.3% (95% confidence interval 5.0-8.0) in STD clinic attenders, around 10% and 21% in female prostitutes in Kingston and Montego Bay respectively and approximately 30% among homosexuals. Syphilis rates and congenital syphilis cases have declined. The proportion of men aged 15-49 years reporting sex with a non-regular partner declined from 35% in 1994 to 26% in 1996 (P< 0.001). Women ever having used condoms increased from 51% in 1988 to 62.5% in 1992 and 73% in 1994 and 1996 (P< 0.001), while condom use with a non-regular partner increased from 37% in 1992 to 73% in 1996 (P= 0.006). Condom use among men was high over the period: around 81% had ever used condoms and 77% used them with non-regular partners. Gay men, inner-city adults and adolescents aged 12-14 years all reported increases in condom use while condom sales and distribution increased from around 2 million in 1985 to 10 million in 1995. CONCLUSION: HIV/STD control measures appear to have slowed the HIV/AIDS epidemic in Jamaica, however a significant minority of persons continue to have unprotected sex in high risk situations.
The poor outlook for gastric cancer in Britain is largely due to late diagnosis. Earlier diagnosis will require both easy access to endoscopy and increased public awareness of dyspeptic symptoms. We used information by personal letter to encourage reporting of potentially significant symptoms in patients over 40 years of age. The aim of this study was to measure the acceptability and effect on gastroscopy rates of home letter information. Patients over 40 registered with 12 general practices were used in the study (practice population 80,000). Patients over 40 from another nine practices (practice population 46,500) acted as controls. A letter encouraging consultation for new dyspeptic symptoms was sent to all study subjects. Gastroscopy rates were compared in both study and control populations. Questionnaires on symptoms were sent to 500 study subjects. The principal outcome measure was the gastroscopy rate in people over 40 in both populations, before and during the intervention. The gastroscopy rate was 23% higher in the study than in the control population during the study (3.32 vs. 2.7%, P = 0.00016, chi 2 = 14.25). Gastroscopy uptake increased by 85% from 1991/2 to 1993/4 in the study group and by 34% in the control group (chi 2 = 14.02, P = 0.00018). Thirty-one per cent of questionnaire respondents had dyspeptic symptoms; only 3% had 'significant' symptoms of between 2 and 52 weeks duration. Home letters are an acceptable and efficient method of increasing gastroscopy uptake in dyspeptic patients over 40.
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3,5-Dichloroaniline is an intermediate in the production of certain fungicides. This study characterized the capacity of 3,5-dichloroaniline and two putative metabolites to induce methemoglobin formation. In vivo intraperitoneal (i.p.) administration of 0.8 mmol/kg 3,5-dichloroaniline resulted in elevated (P < 0.05) methemoglobin levels at 2 and 4 h after injection and returned to control values within 8 h. In vitro methemoglobin generation was monitored in washed erythrocytes incubated for 60 min at 37 degrees C with 4 and 8 mM 3,5-dichloroaniline. Methemoglobin generation in vitro was higher (P < 0.05) than control values in erythrocytes incubated for 30 min with 0.2-0.6 mM 4-amino-2,6-dichlorophenol or 5-100 microM 3,5-dichlorophenylhydroxylamine. The in vitro methemoglobin generating capacity in decreasing order was: 3,5-dichlorophenylhydroxylamine > 4-amino-2,6-dichlorophenol > > 3,5-dichloroaniline. The results of the in vitro studies further indicated that none of the compounds tested induced lipid peroxidation. Erythrocytes incubated with 5-100 microM 3,5-dichlorophenylhydroxylamine in vitro were associated with depletion of glutathione. These results indicated that: (a) 3,5-dichloroaniline and its metabolites can induce methemoglobin formation; (b) the N-hydroxy metabolite was the most potent inducer of hemoglobin oxidation and (c) glutathione depletion was associated with methemoglobin formation by 3,5-dichlorophenylhydroxylamine.
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To understand how the protein and chromophore components of a light-sensing protein interact to create a light cycle, we performed time-resolved spectroscopy on site-directed mutants of photoactive yellow protein (PYP). Recently determined crystallographic structures of PYP in the ground and colorless I2 states allowed us to design mutants and to study their photosensing properties at the atomic level. We developed a system for rapid mutagenesis and heterologous bacterial expression for PYP apoprotein and generated holoprotein through formation of a covalent thioester linkage with the p-hydroxycinnamic acid chromophore as found in the native protein. Glu46, replaced by Gln, is buried in the active site and hydrogen bonds to the chromophore's phenolate oxygen in the ground state. The Glu46Gln mutation shifted the ground state absorption maximum from 446 to 462 nm, indicating that the color of PYP can be fine-tuned by the alteration of hydrogen bonds. Arg52, which separates the active site from solvent in the ground state, was substituted by Ala. The smaller red shift (to 452 nm) of the Arg52Ala mutant suggests that electrostatic interactions with Arg52 are not important for charge stabilization on the chromophore. Both mutations cause interesting changes in light cycle kinetics. The most dramatic effect is a 700-fold increase in the rate of recovery to the ground state of Glu46Gln PYP in response to a change in pH from pH 5 to 10 (pKa = 8). Prompted by this large effect, we conducted a careful reexamination of pH effects on the wild-type PYP light cycle. The rate of color loss decreased about 3-fold with increasing pH from pH 5 to 10. The rate of recovery to the colored ground state showed a bell-shaped pH dependence, controlled by two pKa values (6.4 and 9.4). The maximum recovery rate at pH 7.9 is about 16 times faster than at pH 5. The effect of pH on Arg52Ala is like that on wild type except for faster loss of color and slower recovery. These kinetic effects of the mutations and the changes with pH demonstrate that both phases in PYP's light cycle are actively controlled by the protein component.
The ecotoxicity of styrene was evaluated in acute toxicity studies of fathead minnows (Pimephales promelas), daphnids (Daphnia magna), amphipods (Hyalella azteca), and freshwater green algae (Selenastrum capricornutum), and a subacute toxicity study of earthworms (Eisenia fostida). Stable exposure levels were maintained in the studies with fathead minnows, daphnids, and amphipods using sealed, flowthrough, serial dilution systems and test vessels. The algae were evaluated in a sealed, static system. The earthworms were exposed in artificial soil which was renewed after 7 days. Styrene concentrations in water and soil were analyzed by gas chromatography with flame ionization detection following extraction into hexane. Test results are based on measured concentrations. Styrene was moderately toxic to fathead minnows, daphnids, and amphipods: fathead minnow: LC50 (96 hr), 10 mg/liter, and NOEC, 4.0 mg/liter; daphnids: EC50 (48 hr), 4.7 mg/liter, and NOEC, 1.9 mg/liter; amphipods: LC50 (96 hr), 9.5 mg/liter, and NOEC, 4.1 mg/liter. Styrene was highly toxic to green algae: EC50 (96 hr), 0.72 mg/liter, and NOEC, 0.063 mg/liter; these effects were found to be algistatic rather than algicidal. Styrene was slightly toxic to earthworms: LC50 (14 days), 120 mg/kg, and NOEC, 44 mg/kg. There was no indication of a concern for chronic toxicity based on these studies. Styrene's potential impact on aquatic and soil environments is significantly mitigated by its volatility and biodegradability.