Racial and social predictors of longitudinal cervical measures: the Cervical Ultrasound Study.

OBJECTIVE: To evaluate whether the racial and socioeconomic disparities are present in adverse cervical parameters, and, if so, when such disparities develop. STUDY DESIGN: A prospective cohort study was conducted. 175 women with a prior preterm birth had up to four endovaginal ultrasounds between gestational weeks 16 and 24 (Cervical Ultrasound Trial of the MFMU). Each sociodemographic factor (race/ethnicity, marital status, insurance funding and education) was examined as a predictor of short cervix or U/funnel shape, using multiple logistic and linear regression. Changes in the cervical length and shape across pregnancy and after pressure were also examined. RESULTS: The strongest associations were seen between race and government-funded insurance and short cervix and U shape per funneling (race and length <25 mm per funnel: adjusted odds ratio (OR) 5.52, 2.24 to 13.63; government-funded insurance and length <30 mm per funnel: adjusted OR 3.10, 1.34 to 7.15). Changes in cervical length were not associated with sociodemographics. CONCLUSION: African-American race and, to a lesser extent, insurance funder, are associated with cervical length and shapes that have been associated with preterm birth, and those properties are present largely early in pregnancy.

Local versus global mechanical effects of intramural swelling in carotid arteries.

Glycosaminoglycans (GAGs) are increasingly thought to play important roles in arterial mechanics and mechanobiology. We recently suggested that these highly negatively charged molecules, well known for their important contributions to cartilage mechanics, can pressurize intralamellar units in elastic arteries via a localized swelling process and thereby impact both smooth muscle mechanosensing and structural integrity. In this paper, we report osmotic loading experiments on murine common carotid arteries that revealed different degrees and extents of transmural swelling. Overall geometry changed significantly with exposure to hypo-osmotic solutions, as expected, yet mean pressure-outer diameter behaviors remained largely the same. Histological analyses revealed further that the swelling was not always distributed uniformly despite being confined primarily to the media. This unexpected finding guided a theoretical study of effects of different distributions of swelling on the wall stress. Results suggested that intramural swelling can introduce highly localized changes in the wall mechanics that could induce differential mechanobiological responses across the wall. There is, therefore, a need to focus on local, not global, mechanics when examining issues such as swelling-induced mechanosensing.

Computational model of the in vivo development of a tissue engineered vein from an implanted polymeric construct.

Advances in vascular tissue engineering have been tremendous over the past 15 years, yet there remains a need to optimize current constructs to achieve vessels having true growth potential. Toward this end, it has been suggested that computational models may help hasten this process by enabling time-efficient parametric studies that can reduce the experimental search space. In this paper, we present a first generation computational model for describing the in vivo development of a tissue engineered vein from an implanted polymeric scaffold. The model was motivated by our recent data on the evolution of mechanical properties and microstructural composition over 24 weeks in a mouse inferior vena cava interposition graft. It is shown that these data can be captured well by including both an early inflammatory-mediated and a subsequent mechano-mediated production of extracellular matrix. There remains a pressing need, however, for more data to inform the development of next generation models, particularly the precise transition from the inflammatory to the mechanobiological dominated production of matrix having functional capability.

Predictors of mother-adolescent discussions about condoms: implications for providers who serve youth.

OBJECTIVE: To examine predictors of mother-adolescent communication about condoms. METHODS: Interviews were conducted with 907 mothers of adolescents aged 14 to 17 years in the Bronx, New York; Montgomery, Alabama; and San Juan, Puerto Rico, to determine whether mothers had talked with their adolescent about condoms. RESULTS: By univariate analysis, mother-adolescent communication about condoms was associated with greater knowledge about sexuality and acquired immunodeficiency syndrome, perception of having enough information to discuss condoms, information from a health-related source, less conservative attitudes about adolescent sexuality, perception that the adolescent was at risk for human immunodeficiency virus, greater ability and comfort in discussing condoms, stronger belief that condoms prevent human immunodeficiency virus/acquired immunodeficiency syndrome, and a more favorable endorsement of condoms. In multivariate analyses, mother-adolescent communication about condoms was associated with a less conservative attitude about abstinence until marriage (odds ratio [OR]: 0.73; 95% confidence interval [CI]: 0.54-0.74), greater skill in communicating about sex (OR: 1.13; 95% CI: 1.06-1.20), greater comfort in communicating about sex (OR: 1.31; 95% CI: 1.01-1.69), a more favorable endorsement of condoms (OR: 1.85; 95% CI: 1.17-2.78), and the perception that the adolescent's friends were sexually active (OR: 3.53; 95% CI: 1.97-7.16). CONCLUSION: Parents who communicate effectively about sexuality and safer sex behaviors can influence their adolescents' risk-taking behavior. Health care providers, particularly physicians, can facilitate this communication by providing to parents information about the sexual behavior of adolescents, the risks that adolescents encounter, condom use, condom effectiveness, and how to discuss condoms. They also can make referrals to programs that teach communication skills.

Adolescent sexual risk behavior: a multi-system perspective.

Adolescents are at high risk for a number of negative health consequences associated with early and unsafe sexual activity, including infection with human immunodeficiency virus, other sexually transmitted diseases, and unintended pregnancy. As a result, researchers have attempted to identify those factors that influence adolescent sexual risk behavior so that meaningful prevention and intervention programs may be developed. We propose that research efforts so far have been hampered by the adoption of models and perspectives that are narrow and do not adequately capture the complexity associated with the adolescent sexual experience. In this article, we review the recent literature (i.e., 1990-1999) pertaining to the correlates of adolescent sexual risk-taking, and organize the findings into a multisystemic perspective. Factors from the self, family, and extrafamilial systems of influence are discussed. We also consider several methodological problems that limit the literature's current scope, and consider implications of the adoption of a multisystemic framework for future research endeavors. We conclude with a discussion of the implications of the available research for practitioners working to reduce sexual risk behavior among adolescents.

Adolescent sexual behavior in two ethnic minority groups: a multisystem perspective.

Adolescents are at high risk for a number of negative health consequences associated with early and unsafe sexual activity, such as infection with HIV and other sexually transmitted diseases, as well as unintended pregnancy. In the present study, a multisystem model was applied to one adolescent sexual behavior, penile-vaginal intercourse. Nine hundred seven Black and Hispanic adolescents (aged 14 to 17 years) and their mothers were interviewed. Factors from three systems (self, family, and extrafamilial) that are influential in the lives of adolescents were evaluated using four outcome measures. Factors from most or all systems emerged as predictors of each outcome measure. A cumulative risk index suggested a linear relationship between the number of systems identified as being at risk and indicators of adolescent sexual behavior. The implications for prevention are discussed.

Reconceptualizing adolescent sexual behavior: beyond did they or didn't they?

CONTEXT: Adolescent sexual behavior is typically studied as a dichotomy: Adolescents have had sex or they have not. Broadening this view would lead to a greater understanding of teenagers' sexual behavior. METHODS: Interview data from 907 high school students in Alabama, New York and Puerto Rico were used to examine the relationships between sexual experience and a variety of social, psychological and behavioral variables. Four groups of teenagers are compared: those who did not anticipate initiating sex in the next year (delayers), those who anticipated initiating sex in the next year (anticipators), those who had had one sexual partner (singles) and those who had had two or more partners (multiples). RESULTS: Compared with delayers, anticipators reported more alcohol use and marijuana use; poorer psychological health; riskier peer behaviors; and looser ties to family school and church. Similarly, multiples reported more alcohol and marijuana use, riskier peer behaviors and looser ties to family and school than singles. Risk behaviors, peer behaviors, family variables, and school and church involvement showed a linear trend across the four categories of sexual behavior. CONCLUSIONS: The traditional sex-no sex dichotomy obscures differences among sexually inexperienced teenagers and among adolescents who have had sex. Prevention efforts must be tailored to the specific needs of teenagers with differing sexual experiences and expectations, and must address the social and psychological context in which sexual experiences occur.

HIV/AIDS among African Americans: progress or progression?

OBJECTIVES: To review data on the extent of HIV infection and associated risk behaviors, the occurrence of AIDS, and HIV-related mortality in African Americans and to suggest what can be done to reduce HIV exposure and infection in this population. DESIGN/METHODS: Review of epidemiologic, published, multisite data on HIV infection in, and related behaviors of, African Americans. RESULTS: On every epidemiologic measure in common use, African Americans, compared with the four other federally recognized racial/ethnic groups, have the most severe epidemic. The trend data show continuing growth in the African American epidemic despite the availability of effective behavioral interventions and biomedical treatments. Few published intervention studies with African American populations have been adequately evaluated; nor have they focused proportionately on men who have sex with men, a group in the African American community with continuing high rates of infection. CONCLUSIONS: Rates of HIV transmission and disease among African Americans are high, disproportionate, and are not declining as significantly in response to effective interventions as they are among whites. Attention is urgently needed to increase our understanding of risk behaviors, social networks, and specific factors in the African American community that can be altered to reduce HIV infection. Macroenvironmental factors--poverty, social class, racism--need to be studied to suggest possible intervention components to reduce rates of HIV transmission and to increase the use of therapies that are more effectively slowing disease progression and lowering death rates among whites.

Teaching a foreign language using multisensory structured language techniques to at-risk learners: a review.

An overview of multisensory structured language (MSL) techniques used to teach a foreign language to at-risk students is outlined. Research supporting the use of MSL techniques is reviewed. Specific activities using the MSL approach to teach the phonology/orthography, grammar and vocabulary of the foreign language as well as reading and communicative activities in the foreign language are presented.

Evaluation of a fluorescent lectin-based staining technique for some acidophilic mining bacteria.

A fluorescence-labeled wheat germ agglutinin staining technique (R. K. Sizemore et al., Appl. Environ. Microbiol. 56:2245-2247, 1990) was modified and found to be effective for staining gram-positive, acidophilic mining bacteria. Bacteria identified by others as being gram positive through 16S rRNA sequence analyses, yet clustering near the divergence of that group, stained weakly. Gram-negative bacteria did not stain. Background staining of environmental samples was negligible, and pyrite and soil particles in the samples did not interfere with the staining procedure.

Survival of Anisakis simplex in microwave-processed arrowtooth flounder (Atheresthes stomias).

The purpose of this study was to define the relationship between survival and temperature of nematodes of the species Anisakis simplex in microwave-processed arrowtooth flounder (Atheresthes stomias). Ten fillets (each 126 to 467 g, 0.5 to 1.75 cm thick), with an average of five larvae of Anisakis simplex per fillet, were processed to target temperatures on high (100%) power using a commercial 700-W microwave oven. Fillets were neither covered nor rotated and had a temperature probe inserted to two-thirds depth into the thickest portion. After the fillet was digested using a 1% pepsin solution, the viability of nematodes was determined by viewing them under a dissecting microscope. Survival rates were 31% at 140 degrees F (60 degrees C), 11% at 150 degrees F (65 degrees C), 2% at 160 degrees F (71 degrees C), 3% at 165 degrees F (74 degrees C), and 0% at 170 degrees F (77 degrees C). Microwave processing of standardized fillet "sandwiches," 14 cm long, 4.5 cm wide, and approximately 1.75 cm high, each of which was preinoculated with 10 live nematodes, resulted in no survival at either 160 degrees F or 170 degrees F. Using ultraviolet light to detect both viable and nonviable nematodes in fillet sandwiches as an alternative method to pepsin digestion resulted in survival rates of 1% at 140 degrees F (60 degrees C), 3% at 145 degrees F (63 degrees C), and 0% at 150 degrees F (65 degrees C). Smaller fillet sandwiches, which most likely had fewer cold spots during microwave processing, required 150 degrees F (65 degrees C), whereas larger whole fillets required 170 degrees F (77 degrees C) to kill larvae of Anisakis simplex. The parasites were most likely inactivated by a thermal mechanism of microwave treatment. Damage to the nematodes was often evident from ruptured cuticles that were no longer resistant to digestive enzymes. The high hydrostatic pressure and low chloride content of the pseudocoelomic fluid probably contributed greatly to the damage incurred by the larvae.

Teenage partners' communication about sexual risk and condom use: the importance of parent-teenager discussions.

CONTEXT: Teenagers' communication with their partners about sex and their use of condoms may be influenced by the discussions teenagers have with their parents about sex. However, little is known about the process of parent-teenager communication on this topic. Understanding both what parents discuss with their children and how they discuss it may lead to a greater understanding of teenagers' sexual behavior. METHODS: Interviews were conducted with 372 sexually active black and Hispanic youth aged 14-17 from Alabama, New York and Puerto Rico. Regression analyses were used to examine parent-teenager discussions about sexuality and about sexual risk, and parental communication skills as predictors of teenagers' discussions about sexual risk with a partner and teenagers' condom use. RESULTS: Parent-teenager discussions about sexuality and sexual risk were associated with an increased likelihood of teenager-partner discussions about sexual risk and of teenagers' condom use, but only if parents were open, skilled and comfortable in having those discussions. Teenagers' communication with their partner about sexual risk also was associated with greater condom use, but the relationship between parent-teenager communication and teenagers' condom use was independent of this association. CONCLUSIONS: The influence on teenagers of parent-teenager discussions about sexuality and sexual risk depends on both what parents say and how they say it. Programs that foster parent-teenager communication about sexuality and sexual risk must emphasize both of these aspects.

PIP: Teenagers' communication with their partners about sex, an important factor in sexual risk reduction, has been shown to be influenced by discussions teens have with their parents about sex. The present study confirmed that parent-teen communication about sex does indeed promote teenagers' discussions with their partners about sex and condom use, but only when parents communicate in a skilled, comfortable, and open manner. Interviews were conducted during 1993-94 with 372 sexually active Black and Hispanic US high school students 14-17 years old from Alabama, New York, and Puerto Rico. On average, teens had first intercourse at age 13.7 years and had had 3.9 partners. The association between parent-teen discussions about sexuality and sexual risk and teenager-partner communication about sex was high when parental responsiveness (openness, skill, comfort) was rated high by the teenager, but this association was weaker and of only marginal significance when responsiveness was rated as low. Similarly, when parental responsiveness was high, sexuality and risk discussions were significantly associated with increased condom use during most recent intercourse and lifetime condom use. However, at low levels of parental responsiveness, sexuality discussions were negatively associated with most recent and lifetime condom use. The association between parent-teen communication and condom use was direct and independent. These findings highlight the importance of communication skills training for parents.

Sexually transmitted diseases, unintended pregnancy, and adolescent health promotion.

Adolescence is a critical period in the development of sexual behaviors that may lead to acquiring sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV), and to unintended pregnancy. Understanding adolescent sexual behavior is essential for understanding adolescents' risk of pregnancy and STD/HIV infection and for planning and evaluating health promotion activities. This chapter reviews the sexual behaviors and psychosocial factors associated with STDs and unintended pregnancy among adolescents as well as school-, community-, and clinic-based interventions designed to reduce risk behaviors and promote adolescent sexual health.

Cell surface sialic acid and the regulation of immune cell interactions: the neuraminidase effect reconsidered.

It has been known for over a decade that sialidase (neuraminidase) treatment could substantially enhance the capacity of resting B cells to stimulate the proliferation of allogeneic and antigen specific, syngeneic T cells. Thus, cell-surface sialic acid was implicated as a potential modulator of immune cell interaction. However, little progress has been made in either identifying explicit roles for sialic acid in this system or in hypothesizing mechanisms to explain the "neuraminidase effect." Here we show for the first time that cell surface sialic acid on medium incubated B cells blocks access to costimulatory molecules on the B cell surface, and that this is the most likely explanation for the neuraminidase effect. Further, we show that it is likely to be upregulation of ICAM-1 and its subsequent engagement of LFA-1 rather than loss of cell surface sialic acid that in part regulates access to CD86 and other costimulatory molecules. However, we cannot exclude a role for CD86-bound sialic acid on the B cell in modulating binding to T cell CD28. Because sialidase treatment of resting B cells but not resting T cells enables T cell activation, we suggest that sialidase treatment may still be an analogue for an authentic step in B cell activation, and show that for highly activated B cells (activated with polyclonal anti-IgM plus INF-gamma) there is specific loss 2, 6-linked sialic acid. Potential roles for sialic acid in modulating B cell/T cell collaboration are discussed.

Family communication about sex: what are parents saying and are their adolescents listening?

CONTEXT: Communication between parents and adolescents about sex, particularly in minority families, has been understudied; more information is needed both on which sex-related topics are discussed and on how their content is transmitted. METHODS: Parent-adolescent communication about 10 sex-related topics was examined in a sample of 907 Hispanic and black 14-16-year-olds. Chi-square analyses were performed to test for significant differences across the 10 topics in discussions reported by the adolescents (with either parent) and by the mothers. The openness of communication, parent-adolescent agreement about communication of topics and differences by gender and ethnicity were also examined. RESULTS: Significantly higher proportions of mothers and adolescents reported discussions of HIV or AIDS (92% by mothers and 71% by adolescents, respectively) and STDs (85% and 70%, respectively) than of issues surrounding sexual behavior, contraceptive use and physical development (27-74% for these other eight topics as reported by mothers vs. 15-66% as reported by adolescents). The gender of the adolescent and of the parent holding the discussion, but not the family's ethnicity, significantly influenced findings, with adolescents of both sexes more likely to report discussions with mothers than with fathers, and with parents more likely to discuss any of the 10 topics with an adolescent of the same gender than of the opposite gender. The likelihood of a topic being discussed and of mother-adolescent agreement that a topic was discussed both increased with an increasing degree of openness in the communication process. CONCLUSIONS: Consistent with research among white samples, mothers of black and Hispanic adolescents are the primary parental communicators about sexual topics. To facilitate communication, educational programs for parents should cover not only what is discussed, but how the information is conveyed.

PIP: In the US, Black and Hispanic adolescents have an increased risk of a number of negative consequences of sexual activity, but most studies about parent-adolescent sex communication have been based on White samples, have failed to examine specific content of discussions, have considered the adolescent's perspective only, and have focused on whether (but not how) sexual information is transmitted. This analysis used data from interviews with 982 mother-adolescent pairs who took part in the 1993-94 Family Adolescent Risk Behavior and Communication Study. Sexual communication with either parent was measured by 10 questions to adolescents, sexual communication with adolescent was measured by rewording these questions for mothers, and another 10 questions measured the process of sexual communication. It was found that the topics of HIV/AIDS and sexually transmitted diseases were covered significantly more than other issues. Findings were influenced by the gender of the adolescent and the parent but not by ethnicity. Adolescents of both sexes were more likely to report discussions with mothers than with fathers, and parents were more likely to discuss the 10 topics with adolescents of the same gender. As openness in the communication process increased, so did the likelihood of a topic being discussed and of mother-adolescent agreement that the discussion took place. It was concluded that educational programs for parents should include the topic of how information is conveyed.

Patterns of condom use among adolescents: the impact of mother-adolescent communication.

OBJECTIVES: The association between the timing of discussions about condoms between mother and adolescent and adolescents' condom use during their first and subsequent sexual encounters was examined. METHODS: Sexually active adolescents reported whether and when they discussed condoms with their mother and answered questions about their own condom use. RESULTS: Mother-adolescent discussions about condoms that occurred prior to sexual debut were strongly associated with greater condom use during first intercourse and most recent intercourse, along with greater lifetime regular condom use. CONCLUSIONS: Discussions about condoms prior to sexual debut are important in promoting condom use among adolescents.

Sexual initiation with older male partners and subsequent HIV risk behavior among female adolescents.

Data from a 1993-1994 survey of 150 black and Hispanic teenagers were used to examine differences in HIV risk-related behavior between young women who have a first sexual partner three or more years older than themselves and those whose first partner is their age. Compared with teenagers whose first partner had been roughly their age, the 35% of adolescents with an older partner had been younger at first intercourse (13.8 years vs. 14.6) and less likely to use a condom at first intercourse (63% vs. 82%). They also were less likely to report having used a condom at last intercourse (29% vs. 44%) or having used condoms consistently over their lifetime (37% vs. 56%) or in the previous six months (44% vs. 66%). Some 38% of teenagers with an older first partner had ever been pregnant, compared with 12% of those with a peer-age first partner. The mean number of partners and history of sexually transmitted diseases did not differ between the two groups.

Adolescent heterosexual experience: a new typology.

PURPOSE: The purpose of this paper is to define a typology that encompasses the full range of adolescent heterosexual behavior; to compare the usefulness of the new typology with that of the traditional dichotomy of "sexually active"/"sexually inactive" for understanding sexual behavior among adolescents; and to determine the implications of the new typology for the design and implementation of HIV prevention programs targeting adolescents. METHODS: Detailed face-to-face interviews were conducted with a cross-sectional sample of 907 mothers and their adolescents, ages 14-17 years, recruited from public high schools in Alabama, New York, and Puerto Rico. Information from the adolescent survey on precoital sexual behaviors and STD/HIV sexual risk and risk reduction behaviors was examined. A typology of adolescent heterosexual experiences was constructed using four behavioral dimensions. RESULTS: Ninety-nine percent (n = 894) of the sample was classified into one of the five patterns of sexual experience: Delayers, Anticipators, One-timers, Steadies, and Multiples. Among the participants who were not sexually active, precoital behaviors differed significantly between the 22% who anticipated initiating sexual intercourse in the next year (Anticipators) and those who did not (Delayers). Among those traditionally classified as "sexually active", One-timers and Steadies were significantly older when they first had penile-vaginal intercourse than those who had multiple partners. One-timers were more likely to use condoms than Steadies or Multiples, and only Multiples reported previous STDs. CONCLUSION: A typology that defines a range of adolescent heterosexual experiences was developed, and it was possible to classify 99% of our sample. The traditional dichotomy between "sexually active" vs. "not active" hides important behavioral intentions and sexual practices. These differences must be taken into account in the development and implementation of HIV prevention programs that target adolescents.

Reports of severe physical punishment and exposure to animal cruelty by inmates convicted of felonies and by university students.

A self-report questionnaire designed to assess abusive childhood environments and exposure to animal cruelty was administered to 314 inmates in a prisoner classification center. Although high rates of physical punishment characterized the entire sample, persons charged with violent, but nonhomicidal crimes reported more severely punitive childhood histories than those charged with homicidal crimes, sex offenses, and nonviolent offenses. Some exposure to animal cruelty was widespread in the sample, but there was no association between experiencing animal cruelty and the type of crime committed. Moreover, there were only modest associations between animal cruelty experiences and the aversive childhood histories of the subjects, as well as the subjects' reported use of physical and sexual coercion in dating and intimate relationships. To determine whether the high base rate of exposure to animal cruelty was unique to the incarcerated sample, a follow-up study was completed with university undergraduates. Widespread exposure to some animal cruelty was reported by undergraduates; there were modest associations between reporting animal cruelty and reporting punitive and acrimonious childhood histories. In general, the findings were consistent with the hypothesis that there is an association between punitive childhood histories and antisocial behavior but not consistent with the hypothesis that exposure to animal cruelty is importantly related to antisocial behavior or child maltreatment.