The semantics of sexual behavior and their implications for HIV/AIDS research and sexual health: US and UK gay men's definitions of having "had sex".

Understanding the definition and meaning of the word "sex" has implications for sexual medicine, HIV/AIDS research, and clinical practices. Previous studies have reported variations in the definition of having "had sex" and the necessity of using behaviorally specific terminology when taking sexual histories and assessing sexual risk. The purpose of the current study is to assess gay men's definitions of what constitutes having "had sex." Two international convenience samples are compared: a UK sample of 180 self-identified gay men ranging from 18 to 56 years of age (M=36 years; SD=8.29) and a US sample of 190 self-identified gay men ranging 18-74 years of age (M=33.9 years; SD=12.49). Both groups were asked to indicate whether each of a list of sexual behaviors was considered having "had sex." Almost all participants (~95%) believed that penile-anal intercourse constituted having "had sex." US and UK gay men differed in defining the following as having "had sex": giving oral-genital stimulation (US 71.6%, UK 84.9%, P=0.002); giving (G) and receiving (R) manual-anal stimulation (G: US 53.4%, UK 70.9%, P=0.001; R: US 53.7%, UK 71.2%, P=0.001); giving and receiving oral-anal stimulation (G: US 61.2%, UK 78.4%, P<0.001; R: US 59.3%, UK 78.1, P<0.001); and giving and receiving sex-toy stimulation (G: US 55%, UK 77.1%, P<0.001; R: US 56.1%, UK 77.7%, P<0.001). It is important to note that regardless of country there was not overall consensus on which behaviors constituted having "had sex." These findings reinforce the need for behavioral specificity in documenting sexual histories and assessing sexual risk. Further, researchers and clinicians should exercise caution by not assuming that their own definitions of the term "sex" is shared by their gay male participants or patients.

Thiophene systems. 9. Thienopyrimidinedione derivatives as potential antihypertensive agents.

A series of thieno[3,4-d]-, thieno[3,2-d]-, and thieno[2,3-d]pyrimidine-2,4-diones with (phenylpiperazinyl)alkyl substitution at N-3 have been synthesized and evaluated for antihypertensive effects in spontaneously hypertensive rats (SHR). These 49 compounds were compared to the vasodilator standards prazosin and the isosteric quinazoline-2,4-dione SGB 1534. Substitution at the 2-, 3-, or 4-position of the phenyl ring was examined, with that at the 2-position more potent than 4-substitution while the isomeric 3-substituted compounds were least potent. Neither alkylation nor acylation at the N-1 position improved the antihypertensive effects as compared to hydrogen. The three thienopyrimidine-2,4-diones (3-5) that contain a [(2-methoxyphenyl)piperazinyl]ethyl moiety at N-3 and hydrogen at N-1 were found to be potent oral antihypertensive agents in the SHR with doses (mg/kg, po) for reducing systolic blood pressure (SBP) by 50 mmHg (ED-50SBP) of 0.21, 0.19, and 1.0, respectively. The compounds 1-5 were further evaluated for alpha blocking potency by measuring the iv doses necessary to antagonize the phenylephrine pressor response by 50% (ED50) in the SHR. The ED50 values (micrograms/kg) are 10.4, 3.3, 1.7, 2.1, and 15.4, respectively. These results clearly show that all three thiophene systems have potent activity as antihypertensive agents and that 3 and 4 are more potent than 1 or 2 as alpha 1-antagonists in vivo.

The effects of allopurinol and superoxide dismutase in a rat model of skin flap necrosis.

Oxygen-free radicals have been implicated as mediators of ischemic damage in a number of tissues, including heart, kidney, small intestine, and skin. Superoxide dismutase, a free radical scavenger, and allopurinol, an inhibitor of xanthine oxidase (a catalyst in the formation of superoxide) have been shown separately to decrease ischemic damage to tissue. Sixty-two male Sprague-Dawley rats (220 to 280 g) were divided into five groups: control, superoxide dismutase only, allopurinol only, high-dose combined allopurinol and superoxide dismutase, and low-dose combined allopurinol and superoxide dismutase. An 18-cm2 ventral island skin flap, based on a single inferior epigastric vessel, was raised and replaced. Blood flow was assessed with a perfusion fluorometer immediately after the flap was replaced, and on postoperative days 1 and 3. Gross necrosis was assessed on postoperative day 7. Gross necrosis was reliably reduced in all groups as compared with the control; however, necrosis in any one experimental group was not significantly different from any other experimental group. Necrosis (expressed as a percentage of the area of the random [distal] half of the flap) was as follows for each group: control, 74%; superoxide dismutase, 43%; allopurinol, 43%; high-dose combined, 48%; low-dose combined, 33%. Blood flow, as represented by the dermofluorescence index, was not changed by any of the treatments. Blood flow was also related to the eventual survival or necrosis for any one portion of tissue. All experimental groups survived with significantly less blood flow than the control.(ABSTRACT TRUNCATED AT 250 WORDS)

Extension of neuromuscular pedicles and direct nerve implants in the rabbit.

Extension of neuromuscular pedicles and direct nerve implants was investigated in ten rabbits. All rabbits underwent facial nerve resection bilaterally. In five rabbits a neuromuscular pedicle, based on the ansa cervicalis nerve, was implanted into the denervated mentalis muscle unilaterally. On the opposite side, reinnervation was attempted using a neuromuscular pedicle with an interposed nerve graft. In the other five rabbits, reinnervation was attempted using a direct nerve implant on one side and a direct nerve implant extended with a nerve graft on the opposite side. Evoked electromyographic muscle tension and histologic studies were used to evaluate reinnervation. Functional neuromuscular units were consistently produced with neuromuscular pedicles, direct nerve implants, and extended direct nerve implants, while extended neuromuscular pedicles failed to produce detectable reinnervation.

Acute blood flow changes in rapidly expanded and adjacent skin.

Random flaps raised in expanded skin demonstrate increased survival lengths when compared with flaps raised on an acute basis. Nutritive blood flow studies performed after skin expansion and elevation show augmented blood flows similar to those seen in conventionally delayed skin flaps. We utilized dermofluorometric analysis to study acute blood flow changes in sequentially, rapidly expanded porcine skin. Four subcutaneous pockets were developed in each of six pigs. The pockets were divided into the following three groups: (1) those with placement of a tissue expander inflated sequentially to 300 mL over four days and then totally deflated on day 6, (2) those with placement of a tissue expander that was not inflated, and (3) those with no tissue expander placed. Measurements were taken immediately before and after tissue expander manipulation in group 1 and daily in groups 2 and 3. Fluorescence was determined at points over and 4, 7, and 10 cm distal to the expander. Blood flow decreased immediately after skin expansion in areas over the tissue expander on days 0 and 1 and returned to baseline levels within 24 hours. Blood flow increased after tissue expander deflation on day 6 but returned to predeflation levels within 24 hours. Capillary blood flow increased over the duration of the study in all three groups. There was no significant difference in blood flow between and among the three groups on day 8, nor was there a significant difference in blood flow between and among sites over and distal to the tissue expander.

Contaminant risks from biosolids land application: contemporary organic contaminant levels in digested sewage sludge from five treatment plants in Greater Vancouver, British Columbia.

This study examines the potential for environmental risks due to organic contaminants at sewage sludge application sites, and documents metals and various potential organic contaminants (volatile organics, chlorinated pesticides, PCBs, dioxins/furans, extractable petroleum hydrocarbons, PAHs, phenols, and others) in current production biosolids from five wastewater treatment plants (WWTPs) within the Greater Vancouver Regional District (GVRD). There has been greater focus in Europe, North America and elsewhere on metals accumulation in biosolids-amended soil than on organic substances, with the exception of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans. Another objective, therefore, was to evaluate the extent to which management of biosolids re-use based on metal/metalloid levels coincidentally minimizes environmental risks from organic contaminants. Historical-use contaminants such as chlorophenols, PCBs, and chlorinated pesticides were not detected at environmentally relevant concentrations in any of the 36 fresh biosolids samples, and appear to have virtually eliminated from sanitary collection system inputs. The few organic contaminants found in freshly produced biosolids samples that exhibited high concentrations relative to British Columbia and Canadian soil quality benchmarks included p-cresol, phenol, phenanthrene, pyrene, naphthalene, and heavy extractable petroleum hydrocarbons (HEPHs--nCl9-C34 effective carbon chain length). It was concluded that, with the exception of these petroleum hydrocarbon constituents or their microbial metabolites, the mixing of biosolids with uncontaminated soils during land application and based on the known metal concentrations in biosolids from the Greater Vancouver WWTPs investigated provides adequate protection against the environmental risks associated with organic substances such as dioxins and furans, phthalate esters, or volatile organics. Unlike many other organic contaminants, the concentrations of petroleum hydrocarbon derived substances in biosolids has not decreased within the last decade or more in the WWTPs studied, and--unlike persistent chlorinated compounds--the associated PAHs and other hydrocarbon constituents merit careful consideration, especially in the context of repeated land-application of biosolid.

Effects of local and distant contaminant sources: polychlorinated biphenyls and other organochlorines in bottom-dwelling animals from an Arctic estuary.

Elevated concentrations of organochlorines in the tissues of large marine predators in the Canadian Arctic are well documented. This paper presents some of the first data on the composition and distribution of chlorinated organic compounds in some arctic coastal animals found at lower levels of the marine food chain. Organisms include bottom-dwelling invertebrates: clams (Mya truncata), mussels (Mytilus edulis), sea urchins (Strongylocentrotus droebachiensis) and fish: sculpins (Myoxocephalus quadricornis). The majority of samples were collected in the vicinity of Cambridge Bay, Northwest Territories (NWT), Canada; however, samples were also collected near another inhabited area (Hall Beach, NWT) and at a reference site (Wellington Bay, NWT). PCBs and other organochlorines typically originate in more industrialized parts of the northern hemisphere, enter the Arctic, and are subsequently biomagnified. In this study, differences in the PCB congener compositions and concentrations, as well as the relative concentrations of a larger suite of organochlorines in biota, allowed the discrimination between local and distant PCB sources. Terrestrial runoff from southern Victoria Island, NWT, has resulted in localized elevation of PCBs and chlorinated pesticides in marine sediment and bottom-dwelling animals. The major inputs of PCBs to coastal waters within Cambridge Bay were derived from local sources (the hamlet dump and DEW Line site). In addition, transport from more distant sources via riverine input accounts for locally elevated concentrations of other organochlorines in upper Cambridge Bay. This process may also account for concentrations of all measured organochlorines that are higher in Wellington Bay than in Queen Maud Gulf. The high PCB concentrations in the whole tissue (excluding liver) or livers of four-horned sculpins in Cambridge Bay (up to 220 ng/g and 1950 ng/g, respectively) and, to a lesser extent, Wellington Bay (3.8 ng/g and 47 ng/g, respectively) reflect a strong tendency for biomagnification of PCBs in coastal benthic communities.

Epidural analgesia for labor in a community hospital.

Epidural analgesia offers excellent relief from the pain of uterine contractions during labor. It is well tolerated by both mother and baby. However, recent reports suggest that epidurals increase the rate of both cesarean sections and instrumental deliveries, with their attendant costs and morbidities. At our community hospital, 100 consecutive labors using epidural anesthetics were contrasted with 100 consecutive labors managed without them. No significant differences were found in birth weights, Apgar scores, cesarean section rate, or complications. Forceps use was greatly increased, from 13% to 37% (p < 0.01).

Postpartum mental disorders.

As many as 85 percent of women have some type of postpartum mental illness. Puerperal mental difficulties may have an adverse effect on the relationship between a mother and her newborn. The three categories of postpartum mental illness are the "blues," depression and psychosis. Postpartum blues is a mild, transient disorder that may be a variant of normal maternal behavior following delivery. Depression and psychosis in the postpartum period cannot clearly be distinguished from the same disorders occurring at other times of life, but they respond to traditional modes of therapy.

Heterotopic pregnancy: a reevaluation.

Heterotopic pregnancies, or combined intrauterine and extrauterine pregnancies, were first reported in 1708. Traditionally, the rate of occurrence has been thought to be 1:30,000 pregnancies. It has even been said in the recent literature that an intrauterine pregnancy would rule out an ectopic pregnancy. There is good evidence that this is no longer true. The reported incidence in Western Europe and the United States is most probably 1:2600 pregnancies and much higher in certain high-risk groups. Because heterotopic pregnancy is no longer a medical curiosity, it needs to be considered in the differential diagnosis of abdominal pain in pregnancy, in the management of ectopic pregnancy, and in ovulation induction. This report presents a case encountered in a typical family practice. The literature is reviewed, and probable factors responsible for the markedly increased rate (ovulation induction and increase in ectopics in general) are addressed.

Evaluation of calcium entry blockers and alpha 2-adrenergic antagonists on B-HT 920-induced pressor responses in the autonomically blocked dog.

Several calcium entry blockers and alpha 2-adrenergic receptor antagonists were evaluated for inhibition of pressor responses induced by the selective alpha 2 agonist B-HT 920 in pentobarbital-anesthetized dogs pretreated with prazosin (0.5 mg/kg, i.v.), propranolol (0.5 mg/kg, i.v.), and hexamethonium (10 mg/kg i.v.). In this preparation, autonomic blockade (alpha 1, beta, and ganglionic block) persists for approximately 4 hr. The B-HT 920 administered intravenously causes dose-related increases in mean arterial blood pressure (ED50 = 4.90 micrograms/kg, i.v., dose causing a 50 mm Hg rise in mean arterial blood pressure). Maximum increases in mean arterial pressure approximate 80 mm Hg at 100 micrograms/kg, i.v. Repeated bolus administration of B-HT 920 over a 4-hr period shows no significant reduction in the pressor response, suggesting good stability of this experimental model and no rapidly developing tolerance. Calcium entry blockers (nifedipine, D-600, and diltiazem) and alpha 2-adrenergic receptor antagonists (yohimbine and idazoxan) inhibit the B-HT 920-induced pressor response in a dose-related manner. The ED50 values (dose of antagonist that causes a 50% inhibition of B-HT 920-induced pressor response) were calculated. Idazoxan and yohimbine have ED50 values (mg/kg, i.v.) of 0.086 and 0.063, respectively, whereas D-600, nifedipine, and diltiazem have values of 0.074, 0.111, and 0.542, respectively. The data show that calcium entry blockers and alpha 2-adrenergic blockers are potent inhibitors of B-HT 920 pressor responses in the autonomically blocked dog. This experimental model is appropriate for the evaluation of calcium entry blockers and/or alpha 2-adrenergic antagonists in vivo.