Two doses of subcutaneous methadone for postoperative analgesia in dogs undergoing tibial plateau levelling osteotomies.

OBJECTIVES: To evaluate analgesia, sedation and adverse effects of two doses of subcutaneous methadone in dogs undergoing tibial plateau levelling osteotomy. MATERIALS AND METHODS: Seventeen client-owned dogs undergoing unilateral tibial plateau levelling osteotomy were randomly allocated to receive either 0.25 mg/kg methadone (eight dogs) or 0.5 mg/kg methadone (nine dogs). All dogs were premedicated with methadone and 2 to 6 mcg/kg dexmedetomidine subcutaneously. They were induced and maintained on a standard protocol. All animals received a second dose of methadone subcutaneously 4 hours after premedication and a 4.4 mg/kg dose of carprofen subcutaneously at 8 hours after premedication. During surgery, blood pressure, heart rate and temperature were assessed every 5 minutes. Postoperatively, sedation scores, temperature, heart rate and Glasgow composite modified pain score - short form were assessed for 12 hours postoperatively. RESULTS: One of 17 (5.9%) dogs had intraoperative hypotension, nine of 17 dogs had intra-operative bradyarrhythmias and 17 of 17 dogs had intra-operative hypothermia. No dogs required intra-operative rescue. Composite modified pain score - short form scores were below the threshold for intervention in 16 of 17 (94.1%) animals. Only one of 17 (5.9%) dogs required rescue analgesia. Median sedation score was 0 by the T8 time point. Adverse events were rare in both groups with only vocalisation and hypothermia reported commonly postoperatively. CLINICAL SIGNIFICANCE: Two doses of methadone at either 0.25 or 0.5 mg/kg administered via subcutaneous injections pre-operatively and 4 hours later, along with 4.4 mg/kg carprofen subcutaneously 8 hours after the first methadone dose appear to provide sufficient pain control for up to 12 hours in dogs undergoing tibial plateau levelling osteotomy.

Clinical findings for dogs undergoing elective and nonelective cholecystectomies for gall bladder mucoceles.

OBJECTIVES: The purpose of this study was to describe elective and nonelective post-cholecystectomy complications and mortality rates in dogs with a gall bladder mucocele. The secondary purpose was to report complications and mortality rates for different methods of common bile duct catheterisation. MATERIALS AND METHODS: A multi-institutional retrospective case series was performed to identify dogs with a gall bladder mucocele between 2004 and 2018 that underwent a cholecystectomy. Dogs were classified into nonelective or elective based on the presence or absence, respectively, of gall bladder rupture, biliary duct distension, clinical signs or hyperbilirubinemia. Each cholecystectomy was classified into three groups: duodenotomy and retrograde catheterisation, normograde catheterisation or no catheterisation. Complications were divided into four grades based on increasing severity and mortality rates were assessed for each. RESULTS: The mortality rate was 2 (6%) out of 31 for dogs undergoing an elective cholecystectomy and 21 (23%) out of 90 for dogs undergoing a nonelective cholecystectomy. The complication rate was 52% for the elective cholecystectomy and 50% for nonelective cholecystectomy. The majority of the complications in the elective category were grade 1 (mild). Post-operative hyperthermia developed in 35% of dogs that had a duodenotomy and retrograde common bile duct catheterisation, in 4% of dogs with a normograde common bile duct catheterisation and in 7% of dogs that did not have the common bile duct catheterised. CLINICAL SIGNIFICANCE: Elective cholecystectomy in dogs with a gall bladder mucocele in this study carried a low mortality rate and a relatively high frequency of minor complications.

Nuclear factor-kappaB is constitutively activated in primitive human acute myelogenous leukemia cells.

Human acute myelogenous leukemia (AML) is thought to arise from a rare population of malignant stem cells. Cells of this nature, herein referred to as leukemic stem cells (LSCs), have been documented for nearly all AML subtypes and appear to fulfill the criteria for stem cells in that they are self-renewing and give rise to the cells found in many leukemic populations. Because these cells are likely to be critical for the genesis and perpetuation of leukemic disease, the present studies sought to characterize unique molecular properties of the LSC population, with particular emphasis on the transcription factor, nuclear factor-kappaB (NF-kappaB). Previous experiments have shown that unstimulated human CD34(+) progenitor cells do not express NF-kappaB. In contrast, primary AML CD34(+) cells display readily detectable NF-kappaB activity as assessed by electrophoretic mobility shift assay and gene expression studies. Furthermore, detailed analyses of enriched AML stem cells (CD34(+)/CD38(-)/CD123(+)) indicate that NF-kappaB is also active in the LSC population. Given the expression of NF-kappaB in leukemic, but not normal primitive cells, the hypothesis that inhibition of NF-kappaB might induce leukemia-specific apoptosis was tested by treating primary cells with the proteasome inhibitor MG-132, a well-known inhibitor of NF-kappaB. Leukemic CD34(+)/CD38(-) cells displayed a rapid induction of cell death in response to MG-132, whereas normal CD34(+)/CD38(-) cells showed little if any effect. Taken together, these data indicate that primitive AML cells aberrantly express NF-kappaB and that the presence of this factor may provide unique opportunities to preferentially ablate LSCs.

Expression of tumor-suppressor genes interferon regulatory factor 1 and death-associated protein kinase in primitive acute myelogenous leukemia cells.

Previous studies indicate that human acute myelogenous leukemia (AML) arises from a rare population of leukemic stem cells. Cells of this nature can initiate and maintain leukemic cell growth in both long-term cultures and nonobese diabetic/severe combined immune-deficient mice. To characterize the biology of primitive AML cells, gene expression screens were performed with 7 primary AML and 3 normal specimens. For each sample, stem cell populations (CD34(+)/CD38(-)) were isolated and used to synthesize radiolabeled complementary DNA (cDNA). AML vs normal probes were then hybridized to cDNA arrays containing genes related to cancer and apoptosis. Of approximately 1400 genes analyzed, 2 tumor-suppressor genes were identified that were overexpressed in all 7 of the AML CD34(+)/CD38(-) cell populations: death-associated protein kinase and interferon regulatory factor 1. Expression of each gene was confirmed by reverse-transcription polymerase chain reaction and immunoblot analysis. It is proposed that tumor-suppressor proteins play a role in the biology of primitive AML cells. (Blood. 2001;97:2177-2179)

The interleukin-3 receptor alpha chain is a unique marker for human acute myelogenous leukemia stem cells.

Recent studies suggest that the population of malignant cells found in human acute myelogenous leukemia (AML) arises from a rare population of leukemic stem cells (LSCs). LSCs have been documented for nearly all AML subtypes and have been phenotypically described as CD34+/CD38- or CD34+/HLA-DR-. Given the potentially critical role of these primitive cells in perpetuating leukemic disease, we sought to further investigate their molecular and cellular characteristics. Flow cytometric studies using primary AML tissue showed that the interleukin-3 receptor alpha chain (IL-3Ralpha or CD123) was strongly expressed in CD34+/CD38- cells (98 +/- 2% positive) from 16 of 18 primary specimens. Conversely, normal bone marrow derived CD34+/CD38- cells showed virtually no detectable expression of the CD123 antigen. To assess the functional role of IL-3Ralpha positive cells, purified CD34+/CD123+ leukemia cells were transplanted into immune deficient NOD/SCID mice. These experiments showed that CD123+ cells were competent to establish and maintain leukemic populations in vivo. To begin to elucidate a biological role for CD123 in leukemia, primary AML samples were analyzed with respect to signal transduction activity in the MAPK, Akt, and Stat5 pathways. Phosphorylation was not detected in response to IL-3 stimulation, thereby suggesting CD123 is not active in conventional IL-3-mediated signaling. Collectively, these data indicate that CD123 represents a unique marker for primitive leukemic stem cells. Given the strong expression of this receptor on LSCs, we propose that targeting of CD123 may be a promising strategy for the preferential ablation of AML cells.

A GDP-fucose-protected, pyridoxal-5'-Phosphate/NaBH(4)-sensitive lys residue common to human alpha1-->3Fucosyltransferases corresponds to Lys(300) in FucT-IV.

Human alpha1-->3/4fucosyltransferases (FucTs) contain a common essential pyridoxal-5'-phosphate(PLP)/NaBH(4) reactive, GDP-fucose-protectable Lys. For identification, site-directed mutants at lysines of FucT-IV and -VII were prepared and tested. Non conserved lysine mutants K119Y and K394Q were similar to wild-type FucT-IV. However, mutants of conserved lysines K228R and K300R were distinct. The specific activity of K228R was 2- to 3-fold lower but retained K(m) values for donor and acceptor substrates as wild-type FucT-IV. The specific activity of K300R was reduced over 400-fold with an apparent K(m) for GDP-fucose over 200 microM. FucT-VII mutants K169R and K240R (equivalent to K228R and K300R for FucT-IV, respectively) were inactive. No change in PLP/NaBH(4) sensitivity occurred with K119Y, K228R, and K394Q compared to wild-type FucT-IV. These and previous results (A. L. Sherwood, A. T. Nguyen, J. M. Whitaker, B. A. Macher, M. R. Stroud, and E. H. Holmes, J. Biol. Chem. 273, 25256-25260, 1998) demonstrate that of three conserved lysines in FucT-IV, two (Lys(228) and Lys(283)) are not involved in substrate binding but perhaps in catalysis. The third site, Lys(300), is involved in GDP-fucose binding and PLP/NaBH(4) inactivation.

Position and degree of mismatches and the mobility of DNA heteroduplexes.

Heteroduplex mobility assay (HMA) is a fast and inexpensive method for determining relatedness between DNA sequences. Rapidly evolving viruses such as HIV-1 develop marked sequence differences in their genomes over the course of the epidemic and infection in a single individual. HMA can be used to monitor both processes. Here, we systematically evaluated the influence of single base mismatches on heteroduplex mobility. The impact of mismatches at nine different positions in 559 bp double-stranded DNA molecules, within a background of overall sequence divergence ranging from 1.97 to 9.65%, was evaluated in both non-denaturing and partially-denaturing acrylamide gels. We found that the electrophoretic mobility of heteroduplexes was proportional to the level of mismatch when that level exceeded 4.5%. Overall, mismatches near the center of the fragment and clustered mismatches tended to have an exaggerated influence on the mobility of heteroduplexes. Thus, the use of HMA for quantitative inference of genetic distances under the conditions we describe is of greatest utility at levels of mismatch >5%.

Large-scale monitoring of host cell gene expression during HIV-1 infection using cDNA microarrays.

Human immunodeficiency virus type 1 (HIV-1) infection alters the expression of host cell genes at both the mRNA and protein levels. To obtain a more comprehensive view of the global effects of HIV infection of CD4-positive T-cells at the mRNA level, we performed cDNA microarray analysis on approximately 1500 cellular cDNAs at 2 and 3 days postinfection (p.i.) with HIV-1. Host cell gene expression changed little at 2 days p.i., but at 3 days p.i. 20 cellular genes were identified as differentially expressed. Genes involved in T-cell signaling, subcellular trafficking, and transcriptional regulation, as well as several uncharacterized genes, were among those whose mRNAs were differentially regulated. These results support the hypothesis that HIV-1 infection alters expression of a broad array of cellular genes and provides a framework for future functional studies on the differentially expressed mRNA products.

Consistent viral evolutionary changes associated with the progression of human immunodeficiency virus type 1 infection.

To understand the high variability of the asymptomatic interval between primary human immunodeficiency virus type 1 (HIV-1) infection and the development of AIDS, we studied the evolution of the C2-V5 region of the HIV-1 env gene and of T-cell subsets in nine men with a moderate or slow rate of disease progression. They were monitored from the time of seroconversion for a period of 6 to 12 years until the development of advanced disease in seven men. Based on the analysis of viral divergence from the founder strain, viral population diversity within sequential time points, and the outgrowth of viruses capable of utilizing the CXCR4 receptor (X4 viruses), the existence of three distinct phases within the asymptomatic interval is suggested: an early phase of variable duration during which linear increases ( approximately 1% per year) in both divergence and diversity were observed; an intermediate phase lasting an average of 1.8 years, characterized by a continued increase in divergence but with stabilization or decline in diversity; and a late phase characterized by a slowdown or stabilization of divergence and continued stability or decline in diversity. X4 variants emerged around the time of the early- to intermediate-phase transition and then achieved peak representation and began a decline around the transition between the intermediate and late phases. The late-phase transition was also associated with failure of T-cell homeostasis (defined by a downward inflection in CD3(+) T cells) and decline of CD4(+) T cells to

Genetic manipulation of primitive leukemic and normal hematopoietic cells using a novel method of adenovirus-mediated gene transfer.

Gene transfer into early hematopoietic cells has been problematic due to the quiescent nature of primitive cells and the lack of gene transfer vehicles with high efficiency for hematopoietic cell types. Previously, we have shown that adenoviral vectors can be used for the transduction of normal human progenitors with gene transfer efficiencies of approximately 30%. However, this approach is limited by relatively slow uptake kinetics (24-48 h) and a strong dependence on the presence of exogenous cytokines. Thus, we have modified this approach by combining adenoviral vectors with polycations to generate a virus-polycation complex, or VPC. Vehicles of this nature, when composed of conventional adenoviral vectors and polyamidoamine dendrimers, are a highly efficient means of transducing both normal and acute myelogenous leukemia (AML) cells. Moreover, the kinetics of gene transfer are markedly increased using the VPC strategy, with approximately 70% of transduction complete within 2 h. In this study, using viruses that encode green fluorescence protein (GFP), or the T cell costimulatory molecule B7.1 (CD80), we show that VPC-mediated gene transfer is an effective means of transducing normal and AML cells, including those with a highly primitive phenotype. Our data suggest that transient genetic manipulation of primitive hematopoietic cells can readily be achieved and should therefore permit a variety of research and clinical endeavors.

Gender and ethnic differences in the timing of first sexual intercourse.

CONTEXT: Whether the effect of gender on the risk of first intercourse in influenced by adolescents ethnicity has received limited attention in research on age at first sex. Such information could provide a more complete understanding of adolescent sexual behavior. METHODS: Life-table analysis using data from a population-based, ethnically diverse sample of 87/Los Angeles County youths was employed to estimate the median age at first sex for each gender-and-ethnicity group. Multivariate analysis using proportional hazards techniques was conducted to determine the relative risk of sexual activity among teenagers in each group. RESULTS: Overall, the teenagers in the sample had a median age at first sex of 16.9 years. Black males had the lowest observed median (15.0), and Asian American males the highest (18.1); white and Hispanic males, and white and black females, reported similar ages (about 16.5 years). Hispanic and Asian American females had rates of first sex about half that of white females, although these protective effects were explained by differences in family structure. Even after controlling for background characteristics, black males had rates of first sex that were about 3-5 times the rates of the other gender-and-ethnicity groups. In addition, Asian American males were less likely than Hispanic males to be sexually experienced, and Hispanic males had almost twice the rates of sexual activity of Hispanic females. CONCLUSIONS: Socioeconomic conditions account for ethnic differences among females in the age at first sex, and cultural influences may contribute to the difference between Hispanic males and females; explanations for black males, however, remain elusive.

PIP: This study estimated the effects of gender and ethnic differences on the risk of first intercourse (FI) among a population-based sample of Los Angeles County youths aged 12-17 years. Longitudinal surveys were conducted during 1992-94 and 1994-95. The sample was of the multistage, stratified probability type. The sample included 877 interviewed adolescents in the 1st round and 675 in the 2nd. Almost 50% of respondents were Hispanic. 58% lived with both parents. The median age of intercourse was 16.9 years; 16.6 years for males and 17.2 years for females. Blacks reported the youngest age of FI at 15.8 years. Asian adolescents had the oldest age of FI at 17.6 years. The same pattern occurred for median age at FI. Age at FI did not vary as much by ethnicity for females. White and Black females had younger ages of FI than Asian females. Black males had significantly higher rates of FI than White females. Asian males were less likely than White females to be sexually experienced. Hispanic and Asian females had significantly lower rates of sexual activity than White females. Family structure was significantly associated with risk of sexual activity. With controls for differences in family background, rates of FI differed significantly by ethnicity among males, but not females. Teenagers living with a single parent or step family had significantly higher rates of transition to first sex than those living with both parents. Family structure may measure the effects of family disruption, rather than parenting behaviors. Findings demonstrate that ethnicity and gender are key factors that predict adolescents' risk of becoming sexually active.

Violence and injury in marital arguments: risk patterns and gender differences.

OBJECTIVES: Community-based research on violence against women typically focuses on marital arguments rather than on resulting injuries. This study investigated patterns of victimization, violence perpetration, and injury in marital arguments. METHODS: Data from the National Survey on Families and Households and binomial and multinomial logit models were used to analyze characteristics of those who experienced physical violence, as well as to determine who was the perpetrator and who was the victim. RESULTS: Men and women reported similar behaviors during verbal arguments. Young persons, urban dwellers, the less educated, those with low incomes, and Blacks were more likely to report that there had been physical violence in their marriages in the past year. Ethnicity, income, education, and number and age of children at home were not associated consistently with injury of the wife, the husband, or both. CONCLUSIONS: Persons who report physical violence in their marriage are very similar to those who are at increased risk of interpersonal violence in general. The co-occurrence of street and other nonfamily violence with spousal violence may be a fruitful area for future research.

Condom use to prevent incident STDs: the validity of self-reported condom use.

BACKGROUND: Studies of sexual behavior and of interventions designed to reduce human immunodeficiency virus risk usually depend on self-report. Validation of self-reported condom use measures has not been previously reported in an urban population at high risk for sexually transmitted diseases and human immunodeficiency virus. METHODS: A prospective cohort study was performed in subjects recruited from sexually transmitted disease clinics in Baltimore. At enrollment, a questionnaire was administered that assessed human immunodeficiency virus risk factors and sexually transmitted disease history, and used a retrospective calendar to assess sexual events and condom use over the previous 30 days. Clinical evaluation was performed for sexually transmitted diseases. At follow-up 3 months later, the same procedures were repeated. Incident sexually transmitted diseases at follow-up were defined as new culture or serologically documented diagnoses of gonorrhea, chlamydia, syphilis, or trichomoniasis. RESULTS: In the 323 male and 275 female (total = 598) subjects who completed a follow-up visit, 21% reported using condoms for every act of sexual intercourse over the previous 30 days, 21% reported occasionally using condoms, and 59% reported not using condoms. At follow-up, 21% of subjects had new incident gonorrhea, chlamydia, syphilis, or trichomoniasis. Fifteen percent of the men who were "always" condom users had incident sexually transmitted diseases compared with 15.3% of "never users;" 23.5% of women who were "always" users had incident sexually transmitted diseases compared with 26.8% of "never" users. CONCLUSIONS: In this high-risk population, self-reported condom use is not associated with lower sexually transmitted disease incidence. This finding suggests that self-reported condom use measures, even in a research setting, may be subject to substantial reporting bias.

Comparative behavioral epidemiology of gonococcal and chlamydial infections among patients attending a Baltimore, Maryland, sexually transmitted disease clinic.

Between April 1988 and May 1989, 400 males and 400 females attending a Baltimore, Maryland, sexually transmitted disease clinic were enrolled in a study evaluating and comparing behaviors associated with culture-proven gonococcal or chlamydial infection. The subjects were enrolled consecutively, and were all seen by the same clinician. Among participants of each sex, gonorrhea but not chlamydia was associated with increasing numbers of recent (the past 30 days) sexual partners. Compared with males with neither infection, factors independently associated with increased risk of gonorrhea included age less than 20 years (odds ratio (OR) = 1.93), the presence of genitourinary symptoms (OR = 8.07), and recent exposure to a new sexual partner (OR = 2.78); risk for chlamydial infection in males was associated with genitourinary symptoms (OR = 2.83) and was significantly reduced in those reporting multiple recent (OR = 0.19) or new (OR = 0.07) sexual partners. Among females, age less than 20 years was independently associated with gonococcal (OR = 1.86) and chlamydial (OR = 7.79) infections in comparison with females with neither infection. No other behavioral factors were associated with chlamydial infection for females in this study; however, having a regular sexual partner was associated with significantly elevated risk of gonorrhea (OR = 3.85), while the presence of genital tract symptoms was associated with diminished risk (OR = 0.29) for gonorrhea. These data suggest that there are differences in the behaviors associated with gonorrheal and chlamydial infections and that different strategies may be useful in efforts to control these infections.

Prevalence and patterns of condom use among patients attending a sexually transmitted disease clinic.

The purpose of this study is to evaluate prevalence and patterns of condom use among patients attending a sexually transmitted disease (STD) clinic, who are at increased risk of developing STDs. Interviews of 800 patients attending a Baltimore STD clinic were conducted. The prevalence of condom use was dependent on the measure of use employed. For example, 9 out of 10 patients reported ever having used condoms, slightly less than one-third of the patients reported having used condoms in the past 30 days, and only 17% of the patients reported using a condom at last sex. Use also varied somewhat by type of sexual partner, and within any given relationship, from first to last sexual encounter. The most significant factor corresponding to condom use in the 30 days prior to the interview was number of sexual partners (lifetime and in the last month). Multivariate analyses revealed number of lifetime partners to be the most significant predictor of condom use for men, whereas age was the most significant variable for women. These findings suggest that interventions should focus not only on the individual, but the couple.

PIP: This study evaluated the prevalence and patterns of condom use among patients attending a sexually transmitted disease (STD) clinic who are at increased risk for developing STDs. Interviews were conducted with 800 patients attending a Baltimore STD clinic. The prevalence of condom use was dependent on the measure of use employed; e.g., 9 of 10 patients reported ever having used condoms, slightly less than 1/3 of the patients reported having used condoms in the past 30 days, and only 17% of the patients reported using a condom at last sexual encounter. Use also varied somewhat by type of sexual partner, and within any given relationship, from 1st to last sexual encounter. The most significant factor corresponding to condom use in the 30 days prior to the interview was the number of sexual partners (lifetime and in the last month). Multivariate analyses revealed the number of lifetime partners to be the most significant predictor of condom use for men, whereas age was the most significant variable for women. These findings suggest that interventions should focus not only on the individual but on the couple.

Interpartner reliability of reporting of recent sexual behaviors.

Epidemiologic studies exploring risks for sexually transmitted diseases, including human immunodeficiency virus infection, typically rely on self-report of sexual behaviors. Estimates of the incidence and prevalence of sexual practices are important measures for assessment of behavioral interventions as well as for examining disease transmission. This study examined the degree of agreement within heterosexual couples reporting frequency and type of sexual behaviors, including condom use. Self-reports were obtained from 71 couples attending Baltimore sexually transmitted disease clinics in 1989-1990 regarding the number of days and number of episodes of three specific sexual practices (any type of sexual activity, vaginal sex, and vaginal sex with condom use) over a 30-day period. Paired t test analysis revealed both sexes to be very consistent in their reporting of recent sexual experiences. Multivariate analysis showed that agreement did not vary by socioeconomic status, by whether the partners were married to each other, or by age. These findings suggest that reliable information regarding sexual behaviors may be obtained from men or women.

Cultured Ovules as Models for Cotton Fiber Development under Low Temperatures.

Cotton fibers (Gossypium hirsutum L.) developing in vitro responded to cyclic temperature change similarly to those of field-grown plants under diumal temperature fluctuations. Absolute temperatures and rates of temperature change were similar under both conditions. In vitro fibers exhibited a "growth ring" for each time the temperature cycled to 22 or 15 degrees C. Rings were rarely detected when the low point was 28 degrees C. The rings seemed to correspond to alternating regions of high and low cellulose accumulation. Fibers developed in vitro under 34 degrees C/22 degrees C cycling developed similarly to constant 34 degrees C controls, but 34 degrees C/22 degrees C and 34 degrees C/15 degrees C cycling caused delayed onset and prolonged periods of elongation and secondary wall thickening. Control fiber length and weight were finally achieved under 34 degrees C/22 degrees C cycling, but both parameters were reduced at the end of the experiment under 34 degrees C/15 degrees C cycling. Fibers developed under all conditions had equal bundle tensile strength. These results demonstrate that: (a) cool temperature effects on fiber development are at least partly fiber/ovule-specific events; they do not depend on whole-plant physiology; and (b) cultured ovules are valid models for research on the regulation of the field cool temperature response.

Behavioral contributions to acquisition of gonorrhea in patients attending an inner city sexually transmitted disease clinic.

To begin to define the behaviors that influence gonorrhea acquisition, a case-series of patients attending a sexually transmitted disease clinic was surveyed. Although gonorrhea rates were similar, men and women differed in sexual behaviors predictive of infection. Men with a new or casual partner were more likely to have gonorrhea than men with no such partners (adjusted odds ratio = 2.7); this finding did not hold true for women. Condom use in the previous month reduced the chances of gonorrhea acquisition for both men and women. More than 33% continued to engage in sexual activity after onset of symptoms or knowledge of sexually transmitted disease exposure. Individuals with repeated episodes of gonorrhea exhibited an array of risk-taking behaviors, such as intravenous drug use and casual sex partners. These data suggest the complex nature of the behaviors and sexual contexts within which gonorrhea acquisition occurs.

Adolescent childbearing and high school completion in the 1980s: have things changed?

More adolescent mothers are now graduating from high school than ever before. Since the 1950s, the high school completion rate of women who became mothers at age 17 or younger has nearly tripled--from 19 percent in 1958 to 56 percent in 1986. However, graduation rates did not increase equally for all racial and socioeconomic groups, and the increases did not occur in the same periods for all groups. Black mothers who were school-age when they had their first child made their greatest gains in graduation rates between 1958 and 1975, while their white counterparts made their greatest gains between 1975 and 1986. By 1986, black women who were 17 or younger when their first child was born were more likely to have graduated than similar white women--61 percent and 54 percent, respectively. Nevertheless, when overall levels of high school graduation are considered, white women were more likely than black women to have graduated. Regardless of race, women from more advantaged backgrounds were more likely to be graduates than were those from less advantaged backgrounds, and the younger the women were when their first child was born, the less likely they were to be graduates.

Determinants of emergence of antibiotic-resistant Neisseria gonorrhoeae.

Studies were carried out to evaluate the prevalence and risk factors for antibiotic-resistant Neisseria gonorrhoeae infections. Monthly surveillance of gonococcal isolates showed the prevalence of gonococci with high-level, plasmid-mediated tetracycline resistance (TRNG) to be about 15% for three consecutive 6-mo periods. Over the same period, the prevalence of gonococci with chromosomally mediated resistance to penicillin G steadily increased, from 0% to 9% and then to 21%. From April to July 1987, while chromosomally mediated penicillin resistance was rapidly increasing, a more intensive study was conducted. Patients infected with TRNG reported significantly more lifetime sexual partners (P less than .05) but otherwise resembled patients infected with antibiotic-sensitive gonococci. Patients infected with chromosomally mediated penicillin-resistant gonococci differed from other patients. In addition to reporting more lifetime partners (P less than .05), patients with chromosomally mediated penicillin-resistant gonorrhea were more likely to be older (P less than .05) and more often reported past episodes of gonorrhea (P less than .05), greater numbers of recent sexual partners (P less than .05), new sexual partners (P less than .05), prostitute contact (P = .06), and parenteral drug use or sexual partners who were drug users (P = .07). The introduction of antibiotic-resistant N. gonorrhoeae into communities may be attributable to a subset of patients who practice "risky behaviors" and who could be targeted for disease intervention activities.