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PubMed1997

Condom use and first-time urinary tract infection.

We evaluated the effects of condom use, lubricated condom use, and spermicide use on risk of acquiring first urinary tract infection in a case-control study of sexually active college women ages 18-39 years. Cases (N = 144) were women with first urinary tract infection that was confirmed by culture recruited at the student health service; controls (N = 286) were women without a history of urinary tract infection who were randomly sampled from all women enrolled at the university. Participants completed a self-administered questionnaire regarding type and frequency of condom use during the previous 2 weeks. Condoms and spermicides usually were used in combination with each other or oral contraceptives. After adjusting for frequency of vaginal intercourse, using unlubricated condoms compared with using no birth control method strongly increased the risk of first urinary tract infection (odds ratio = 29.1; 95% confidence interval = 3.1-1,335). Using a lubricated condom (with or without spermicide in the lubricant) or a spermicidal cream or gel with an unlubricated condom was associated with two- to eightfold risk of first urinary tract infection. Unlubricated condom use was strongly associated with risk of first urinary tract infection, but this effect was largely neutralized by using a spermicidal cream or gel with the unlubricated condom or by using a lubricated condom.

Adolescent↗
PubMed1991

Sexual behaviour and use of the condom among Ugandan students.

HIV infection is widespread in Uganda. Have its university students, the country's leaders of tomorrow, taken appropriate action? A questionnaire was completed by 661 men and 270 women in a one-in-four sample of Makerere University undergraduates (93% response rate). More than 60% of the men and 36% of the women reported at least two sexual partners in the past year. Over 18% of respondents reported at least one episode of sexually transmitted disease in the past year. Most respondents correctly identified the main routes of HIV transmission but risk was also often incorrectly associated with non-penetrative sex. Only a minority saw the condom as an effective preventive method: most saw it as unsafe or an encouragement to promiscuity. Condoms had been used by 35% of men and 24% of women but were currently always used by only 9% of men and 11% of women. The condom was approved of by only one quarter of respondents. Condom use increased with the number of sexual partners but was less likely if the respondent had seen official publicity about the condom. Whilst there were some encouraging signs of behaviour change, opportunities for the spread of HIV continued to abound in this important group. More positive promotion of the condom is urgently required.

Adult↗
PubMed1996

Knowledge about sexually transmitted diseases in rural and periurban communities of the Asaro Valley of Eastern Highlands Province: the health education component of an STD study.

Community health education played a major role in a study of sexually transmitted diseases (STDs) and other reproductive tract infections which we conducted in rural and periurban communities of the Asaro Valley near Goroka in the Eastern Highlands Province of Papua New Guinea. We found that most women had little knowledge about STDs, which they often did not realize were sexually transmitted. Even major signs and symptoms were thought to be normal and many women had not sought treatment until irreversible damage was done. Knowledge of the complications of STDs, such as infertility and stillbirth, was also slight in these women. It is apparent that there is a desperate need for more reproductive health education at the community level. In developing our health education methods, we found that simple line drawings of male and female reproductive organs and of people with different signs of STDs proved useful. These were quick and easy to produce from readily available materials. It was important to separate men and women into different groups with educators of the same sex, and to create a very informal atmosphere, encouraging free-ranging discussion. Following health education and sensitive interviewing, almost all the women selected for the community-based study of the prevalence of reproductive tract infections consented to vaginal examination, even if they were asymptomatic. Additionally, many nonselected women requested examination.

Adolescent↗
PubMed1996

A primary culture model of rabbit conjunctival epithelial cells exhibiting tight barrier properties.

PURPOSE: The present study was conducted to develop and characterize a functional primary culture of pigmented rabbit conjunctival epithelial cells on permeable support exhibiting tight barrier properties. METHODS: Conjunctival epithelial cells were isolated by 0.2% protease treatment, cultured at 0.5-1.8 x 10(6) cells/cm2 onto collagen-treated Transwell filters, and were maintained either in the presence of 1% fetal bovine serum throughout or serum-free media from day 3 onwards. Transepithelial potential difference (PD) and transepithelial electrical resistance (TEER) were measured and equivalent short-circuit current (Ieq = PD/TEER) estimated. RESULTS: There appears to be a critical plating density of 1.5 x 10(6) cells/cm2 for functional development of tight epithelial cell cultures. The culture conditions as noted above did not affect either the time when peak bioelectric parameters were attained (days 8-10) or the magnitude of these parameters at a plating density of 1.5 x 10(6) cells/cm2. Specifically, cells grown in a serum-free media showed a peak TEER of 1.9 +/- 0.2 k omega.cm2, a PD of 14.2 +/- 1.6 V (apical side negative), and and Ieq of 8.0 +/- 0.4 microA/cm2 (mean +/- SEM, n = 45). Electron microscopy of serum-weaned cultures revealed a multilayered epithelium with numerous microvilli on the outermost layer of cells, while sporadic positive Periodic Acid Schiff (PAS) staining under light microscopy suggested the presence of mucin-secretory goblet cells. CONCLUSIONS: A functional, tight, epithelial barrier of the pigmented rabbit conjunctiva on a permeable support has been developed, which may be useful for mechanistic studies of ion and drug transport at the cellular level.

Animals↗
PubMedDate not supplied

Contraceptive use and fertility in Guatemala.

In 1983, one-quarter of married Guatemalan women aged 15-44 years were using contraception, and female sterilization was the most prevalent method. Fertility rates for the population were at correspondingly high levels, with an overall total fertility rate of about six births per woman. Contraceptive prevalence varied by residence and ethnic group; less than 5 percent of currently married Indian women and about 50 percent of married women in the capital city area were using contraception. From 1978 to 1983, prevalence increased overall by six percentage points, with surgical contraception accounting for most of the increase. Findings of the study suggest that different strategies need to be employed among Ladino and Indian women in order to increase contraceptive prevalence in these subgroups.

Adolescent↗
PubMed2002

[Effect of infrasound on ultrastructure and permeability of rat's blood-retinal barrier].

OBJECTIVE: To investigate the possible effect of infrasound on the ultra-structure and permeability of rat's blood-retinal barrier (BRB). METHODS: Ultra-structural changes of BRB were observed through the injection of lanthanum nitrate (La), which was used as a tracer to demonstrate the breakdown of the BRB, into blood vessels. Fifteen mature male rats divided into 5 groups were exposed to infrasound at a 8 Hz frequency, 130 dB sound pressure level in a pressure chamber especially designed for the experiment for 0, 1, 7, 14, 21 days, respectively. RESULTS: Under the action of infrasound, along with the prolongation of exposure, the damage of BRB was severer and severer. On the 1st day, there was no significant change in La leakage. On the 7th day, La diffused in the interphotoreceptor space at nuclear level. On the 14th day, La granules could be seen in the space of nervous cells. Finally, on the 21st day, La was found between synapses, synapses and nerve cells, as well as between the nerve cells and supporting cells, then sometimes reached vitreous body. Under the electron microscope, there were no significant morphological changes, but changes related to metabolism, such as edematous mitochondria, dilated rough endoplasmic reticula, precipitation of glycogen grandules, widening of perinuclear space, etc. CONCLUSIONS: The results thus suggest that the exposure to infrasound cause the breakdown of rat's blood-retinal barrier and visual impairment.

Animals↗
PubMed2002

Effects of various principles from Chinese herbal medicine on rhodamine123 accumulation in brain capillary endothelial cells.

AIM: To search for novel effective P-glycoprotein (P-gp) reversal agents in the blood-brain barrier (BBB). METHODS: Using rhodamine123 (Rh123) to examine the functional activity of P-gp in cultured bovine brain capillary endothelial cells (BCEC) and screen various principles on P-gp modulation in BBB. RESULTS: All of tested compounds (1-10 micromol/L) increased the intracellular accumulation of Rh123 in a concentration-dependent manner. The rank order of these agents in increasing Rh123 accumulation in BCEC was: cyclosporin A (CsA) > tetrandrine (Tet) > vincrinstine (VCR) approximate, equals flunarizine (Flu) > dl-tetrahydropalmatine (dl-THP) > dauricine (DRC) > azithromycin (Azi) > verapamil (Ver) approximate, equals berbamine (BBM) > daurisoline (DRS) > berberine (BBR) approximate, equals doxorubicin (Dox) > l-tetrahydropalmatine (l-THP) > tetramethylpyrazine (TMP). These agents at concentration of 10 micromol/L increased Rh123 accumulation by 346 %, 203 %, 136 %, 129 %, 115 %, 103 %, 92 %, 87 %, 81 %, 75 %, 67 %, 67 %, 63 %, and 54 %, respectively. The effects of CsA, Tet, Ver, Flu, Azi, and dl-THP on cellular accumulation of Rh123 in BCEC were reversible. When CsA, Tet, Ver, Flu, Azi, or dl-THP-pretreated BCEC were examined at 48, 36, 24, 36, 36, or 12 h, respectively, after removing the agent, the amount of cellular Rh123 accumulation in BCEC returned to control levels (no drug treatment). CONCLUSION: The functional activity of P-gp on the blood-brain barrier could be modulated by various MDR-reversing agents and some principles with low toxicity extracted from medicinal herbs, such as some isoquinoline alkaloids without permanent modifying effects on the intrinsic level of P-gp function.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1999

Condom practices of urban teens using Norplant contraceptive implants, oral contraceptives, and condoms for contraception.

OBJECTIVES: The availability of long-acting hormonal birth control methods has created new contraceptive options for adolescents. The purpose of this study was to determine whether teens initiating these methods use condoms less frequently than teens using oral contraceptive pills or condoms alone and may therefore be at an increased risk of acquiring sexually transmitted infections. STUDY DESIGN: To investigate ongoing condom behavior in teens using levonorgestrel (Norplant) contraceptive implants, oral contraceptives, and condoms alone, we examined data from a 2-year prospective cohort study of 399 urban teens. The study consisted of 3 clinic-based cohorts of adolescent female contraceptive users: Norplant contraceptive implants (n = 200), oral contraceptives (n = 100), and condoms alone (n = 99). Data were collected at an admission interview and at 1- and 2-year follow-up from method continuers. RESULTS: Norplant contraceptive implant users were less likely than oral contraceptive or condom users to report condom use at last sex or consistent condom use at 1- and 2-year follow-up. The implant group showed a significant decrease in condom use from admission to 2 years after method initiation. The proportion of implant users self-reporting new sexually transmitted infections at 2-year follow-up, however, was not significantly greater than that of oral contraceptive or condom users. CONCLUSIONS: Our findings indicate that teen users of Norplant contraceptive implants are less likely to use condoms than teens who choose oral contraceptives but, probably because of differences in sexual behavior, are no more likely to self-report sexually transmitted infections. Our findings also indicate that teens who choose oral contraceptives and condoms do not use them consistently enough to avoid pregnancies or sexually transmitted infections.

Adolescent↗
PubMed1998

Assessing condom use practices. Implications for evaluating method and user effectiveness.

BACKGROUND: Consistent and correct condom use remains important to human immunodeficiency virus (HIV) prevention. Although many studies evaluate consistent condom use, few examine how condoms are used during intercourse. GOALS: Assess how user practices affect exposure to risks of pregnancy and infection during condom use. STUDY DESIGN: A cross-sectional survey on condom behaviors in the past month was conducted among 98 male students attending two Georgia universities. RESULTS: Altogether, 35 of 270 total condom uses (13.0%, 95% confidence interval, 7.4-18.5) resulted in potential exposure to sexually transmitted disease and/or HIV infection or pregnancy. Both consistent and inconsistent users were similarly likely to report potential exposures during condom use. CONCLUSION: These findings suggest condom problems occur among both consistent and inconsistent users. Future studies of condom effectiveness must distinguish whether condoms were used both consistently and correctly.

Adolescent↗
PubMed2003

Closure of the blood-brain barrier by matrix metalloproteinase inhibition reduces rtPA-mediated mortality in cerebral ischemia with delayed reperfusion.

BACKGROUND AND PURPOSE: Intravenous recombinant tissue plasminogen activator (rtPA) can be beneficial in ischemic stroke despite an increased risk of hemorrhage and potential neurotoxic effects. We hypothesized that rtPA-mediated adverse effects depend on the timing of reperfusion and injury to the blood-brain barrier (BBB). METHODS: Male Wistar rats had middle cerebral artery occlusion (MCAO) by intraluminal thread placement. Intervals of ischemia/reperfusion, respectively, in hours were 0/18, 1.5/16.5, 3/15, 6/12, 18/0, and 6/1. Animals received either rtPA or saline for 1 hour at the time of reperfusion or, for the 18/0 trial, starting 1 hour after MCAO. Outcome parameters were mortality, matrix metalloproteinase-2 and -9 (MMP-2 and -9) concentrations, tissue hemoglobin, and brain water content. We analyzed the permeability of the BBB by using the brain 14C[sucrose] uptake method. Effects of the MMP inhibitor BB-94 on the BBB without rtPA treatment and on mortality with rtPA were tested in animals with 6/1 and 6/12, respectively. RESULTS: In delayed reperfusion (6/12), rtPA increased mortality from 17% to 83% (P<0.01) without significantly affecting other outcome parameters. In 6/1, sucrose uptake in the ischemic hemisphere was markedly increased (8.80+/-1.14% vs 2.15+/-0.26%; P<0.01). This uptake was reduced by treatment with BB-94 (3.95+/-1.48%, P<0.01). Furthermore, BB-94 reduced rtPA-mediated mortality in 6/12 to 33% (P<0.05). CONCLUSIONS: rtPA-mediated mortality in delayed reperfusion is associated with early opening of the BBB. Closure of the BBB with BB-94 given before rtPA treatment reduced mortality, suggesting that treatment with MMP inhibitors might reduce the risk associated with thrombolysis.

Animals↗
PubMedDate not supplied

The effectiveness of video-based interventions in promoting condom acquisition among STD clinic patients.

GOAL OF THIS STUDY: This study examined the effectiveness of video-based patient education interventions on promoting condom use among men and women seeking services at a large public STD clinic in New York City. METHODS: Culturally sensitive video-based interventions designed to promote safer sex behaviors were evaluated in a randomized study of black and Hispanic male and female STD clinic patients. Subjects (n = 1,653) were randomly assigned to one of three groups: 1) control, 2) video viewing, and 3) video viewing followed by participation in an interactive group session led by a trained facilitator. The authors examined 1) the effectiveness of interventions in increasing STD and condom-related knowledge, positive attitudes about condoms, human immunodeficiency virus/STD risk perceptions, and self-efficacy and 2) the relationships among these variables, level of intervention, and condom acquisition, a behavioral measure of condom use. RESULTS: Compared with a control group, subjects assigned to video viewing demonstrated greater knowledge about condoms and STDs, more positive attitudes about condom use, increased human immunodeficiency virus/STD risk perceptions, greater self-efficacy, and higher rates of condom acquisition. Subjects assigned to video viewing followed by interactive sessions demonstrated still further increases in risk perceptions, self-efficacy, and condom acquisition, but not in knowledge or condom attitudes. A significant proportion of the association between the behavioral outcome of condom acquisition and level of intervention is attributable to the impact of interventions on risk perception and self-efficacy. CONCLUSIONS: Based on extensive formative research that identified barriers to safer sex behaviors, video-based interventions were developed to promote condom use among black and Hispanic men and women attending STD clinics. Designed to be integrated into clinic services, these interventions help improve knowledge, promote positive attitudes about condoms, and increase condom acquisition among individuals at high risk of acquiring and transmitting human immunodeficiency virus infection and other STDs.

Black or African American↗
PubMed1995

A cross-sectional survey of condom use in conjunction with other contraceptive methods.

A cross-sectional survey of 3,136 women attending family planning clinics in Texas was conducted to examine past use of and future plans for use of condoms by partners during sexual intercourse for disease prevention in conjunction with other contraceptive methods. Following the receipt of clinical services, including counseling about family planning and disease prevention, both contraceptive and planned condom use reporting increased for the majority of subjects. However 22% of the sample indicated that they intended to reduce condom use in the future and instead use a contraceptive which protects from pregnancy but not from disease. Condom use was indicated more frequently for those who reported at least one risk factor for HIV, but 17% of those at risk indicated lower future condom use than past use. This suggests that without changes in risk behavior, these women will be at increased risk of HIV or another sexually transmitted disease.

Adolescent↗
PubMed1990

Sexual behavior of college women in 1975, 1986, and 1989.

To compare sexual practices in college women before and after the start of the current epidemics of Chlamydia trachomatis, genital herpesvirus, and human immunodeficiency virus type 1 infection, we surveyed 486 college women who consulted gynecologists at a student health service in 1975, 161 in 1986, and 132 in 1989 at the same university. There were no statistically significant differences in age, age at menarche, or reason for visiting the gynecologist. The percentages of women in this population who were sexually experienced were the same in all three years (88 percent in 1975, 87 percent in 1986, and 87 percent in 1989). Oral contraceptives were used by 55 percent of the women in 1975, 34 percent in 1986, and 42 percent in 1989; the use of condoms as the usual method of birth control increased (6 percent in 1975, 14 percent in 1986, and 25 percent in 1989; P less than 0.001). In 1975, only 12 percent reported the regular use of condoms during sexual intercourse, in some cases in conjunction with other methods of contraception, as compared with 21 percent in 1986 and 41 percent in 1989 (P = 0.0014). No significant differences were found in the three surveys in the number of male sexual partners or the frequency of fellatio, cunnilingus, or anal intercourse. An additional sample of 189 college women who did not consult the health service was surveyed in 1989, and similar sexual behavior was reported by those who were sexually experienced (65 percent). We conclude that in this population there has been little change in sexual practices in response to new and serious epidemics of sexually transmitted diseases, with the exception of an increase in the use of condoms (which still does not reach 50 percent).

Adolescent↗
PubMed1996

Relationship of alcohol use and risky sexual behavior: a review and analysis of findings.

In this review article, three methodologic approaches that have been used to examine the association between adolescents' alcohol use and their involvement in risky sex are discussed: global correlation studies, situational covariation studies, and event analyses. The strengths and limitations of each of these research methods are discussed. An extensive review of the most rigorous studies, which used event analysis to examine the alcohol-risky sex link, reveals positive results for first-time sexual events but equivocal findings for other types of sexual relationships. It is argued that differences in the types of sexual relationships studied have been confounded, limiting our ability to evaluate the extent to which alcohol has a causal influence on adolescents' condom use. It is suggested that future investigations consider the nature of the sexual relationship, and go beyond studying the length or status of the relationship to explore how variation in relationship dimensions such as trust and intimacy affect adolescents' sexual behavior.

Adolescent↗
PubMed1992

Polyethylene glycol superoxide dismutase and catalase attenuate increased blood-brain barrier permeability after ischemia in piglets.

BACKGROUND AND PURPOSE: Transport of urea across the blood-brain barrier is increased during postischemic cerebral reperfusion in the piglet. Ischemia/reperfusion also has been observed to increase apparent superoxide anion generation on the surface of the brain. The present study was designed to address the hypothesis that the increased transfer of urea into the brain after ischemia/reperfusion could be due to superoxide anion-induced alterations in blood-brain barrier permeability. METHODS: Blood-to-brain transfer of carbon-14-labeled urea was measured in four groups (n = 7 each) of newborn pigs: 1) control (no ischemia, no pretreatment), 2) pretreatment with polyethylene glycol superoxide dismutase (1,000 IU/kg) and polyethylene glycol catalase (10,000 IU/kg i.v.) but no ischemia, 3) no pretreatment and 20 minutes of ischemia followed by 2 hours of reperfusion, and 4) pretreatment with polyethylene glycol superoxide dismutase and polyethylene glycol catalase in addition to ischemia/reperfusion. The following brain regions were investigated: cerebrum, caudate, midbrain, pons, medulla, and cerebellum. RESULTS: Polyethylene glycol superoxide dismutase inhibited generation of superoxide anion by the brain during reperfusion after ischemia. Regional transfer of [14C]urea from blood to brain increased at 2 hours' reperfusion. This ischemia-induced increase in blood-to-brain transfer of [14C]urea was attenuated by pretreatment with polyethylene glycol superoxide dismutase and polyethylene glycol catalase: e.g., cerebrum Kin was 28 +/- 2 in the control group, 26 +/- 3 in the pretreated/no ischemia group, 67 +/- 5 in the untreated/ischemia group, and 40 +/- 2 ml.g-1.s-1.10(6) in the pretreated/ischemia group. After ischemia/reperfusion, cerebral blood flow was unchanged by pretreatment with polyethylene glycol superoxide dismutase and polyethylene glycol catalase. CONCLUSIONS: These data suggest that production of a partially reduced species of oxygen contributes to the increased urea transfer across the blood-brain barrier after ischemia in the newborn pig.

Animals↗
PubMedDate not supplied

Condom use and attitudes among heterosexual college students.

INTRODUCTION: This paper analyzes differences between heterosexual male and female college students' behaviour, attitudes and knowledge about condom use. METHOD: A convenience sample of 707 students were recruited at sexual health displays to complete an anonymous questionnaire. RESULTS: Based on reported sexual partners in the previous year, 486 students (51.2% male and 48.8% female) were classified as heterosexual. No significant differences were found between the sexes in reported risk behaviour. Females reported more appropriate condom use techniques than males, and more positive attitudes toward condoms. Males rated sexual enjoyment to be more important. A greater proportion of males than females gave reasons for not using condoms. CONCLUSION: Differences between male and female attitudes and behaviour are important to address in AIDS prevention. Along with an emphasis on the improvement of condom use techniques, it is critical to focus on gender issues of assertiveness, power and trust.

Adolescent↗
PubMed2004

[Effect of borneol on the intercellular tight junction and pinocytosis vesicles in vitro blood-brain barrier model].

OBJECTIVE: To explore the mechanism of borneol in opening the blood-brain barrier (BBB). METHODS: Borneol contained serum was prepared and using Matin-Darby canine kidney epithelium (MDCKE) cell line as the in vitro BBB model to observe the effects of borneol on intercellular tight junction (ICTJ) and pinocytosis vesicles of BBB model. RESULTS: Borneol reduced the ICTJ and caused increase of the number and enlarged the diameter of vesicles. The ICTJ was opened firstly 4 hrs after borneol treatment, then the pinocytosis was affected 24 hrs later. The effects disappeared 24 hrs after removal of the borneol contained serum, indicating that the above-mentioned effects were reversible. CONCLUSION: Borneol could obviously loosen the ICTJ in BBB, accelerate the transportation of substance through the intercellular passage, it also could increase the number and volume of pinocytosis vesicles in BBB cells, thus to accelerate the transportation of substance by way of cell pinocytosis.

Animals↗
PubMedDate not supplied

Corneal epithelial permeability after excimer laser photorefractive keratectomy.

PURPOSE: To evaluate the effect of excimer laser photorefractive keratectomoy (PRK) on the corneal epithelial barrier function. METHOD: Corneal uptake of 5,6 carboxyfluorescein (CF) was measured by Bernal and Ubels' method after excimer laser PRK in New Zealand white rabbits (N = 40). One cornea in each rabbit was treated, and the fellow cornea was used as a control. In both eyes, the central 7.0 mm of the corneal epithelium was removed. Myopic PRK treatments were performed at 37.75 microns (3.3 diopters [D]) and at 52.50 microns (5.0 D). The animals were euthanized and the eyes placed in CF for 5 minutes at 3 days, and at 1, 2, and 4 weeks following PRK. The corneas were then excised and dialyzed in balanced salt solution. The CF concentration in the dialysate was measured by fluorometry. Four corneas were also prepared for transmission electron microscopy using fixative containing ruthenium red. RESULTS: Three days after PRK, CF uptake increased in all study eyes compared with normal eyes (n = 5). One week after PRK, the control corneas showed a decreased CF uptake while the study corneas still had an increased CF uptake (P < .05). Two weeks after PRK, CF uptake in corneas with a 5.0 D ablation remained increased but decreased in corneas with a 3.3 D ablation (P < .05). Four weeks after PRK, CF uptake returned to normal in all corneas. The ruthenium red penetrated into the deeper layers of the corneal epithelium 1 week after PRK; only the superficial cell layer was stained 4 weeks after PRK. CONCLUSIONS: Excimer laser PRK affected the corneal epithelial barrier function at 1 and 2 weeks postoperatively even though the corneal epithelium covered the ablated area. Deeper laser ablations showed higher corneal CF uptake for longer periods than shallower ablations.

Animals↗