Prevalence of genital chlamydial infection in young women entering a national job training program, 1990-1997.

OBJECTIVES: This analysis describes trends in the prevalence of genital chlamydial infection in economically disadvantaged young women entering a national job training program. METHODS: We examined chlamydia test data for May 1990 through June 1997 for women aged 16 to 24 years who enrolled in the program. The significance of trends was evaluated with the chi 2 test for trend. RESULTS: Prevalence of chlamydial infection declined 32.9%, from 14.9% in 1990 to 10.0% in 1997 (P < .001). Prevalence decreased significantly in all age groups, racial/ethnic groups, and geographic regions. CONCLUSIONS: The decrease in prevalence of chlamydial infection suggests that prevention activities have reached disadvantaged women across the United States; however, prevalence of chlamydial infection remains high, and enhanced prevention efforts in disadvantaged communities are urgently needed.

Screening for sexually transmitted infections among economically disadvantaged youth in a national job training program.

PURPOSE: To evaluate results of screening for syphilis, gonorrhea, and chlamydia among youth in a federally funded job training program. METHODS: Data were evaluated from medical records of 12,881 randomly selected students in 54 U.S. job training centers during 1996. The intake medical evaluation includes serologic testing for syphilis. The policy was for females to receive a pelvic examination with gonorrhea and chlamydia testing and for males to be first screened with a urine leukocyte esterase (LE) assay, with follow-up gonorrhea and chlamydia testing for those with positive LE results. RESULTS: Adjusting for our sampling strategy, among females, an estimated 9.2% had a positive chlamydia test, 2.7% a positive gonorrhea test, and 0.4% had a positive syphilis test. Gonorrhea and chlamydia rates among females were highest in African-American followed by Native American students. Chlamydia infection was most common in younger women < or = 17 years of age. An estimated 0.1% of males had a positive syphilis test, and 4.8% of males a positive urine LE test. Of 103 LE-positive males tested for gonorrhea and chlamydia, only 27 (26%) had a positive test for one of these STDs. CONCLUSIONS: Our study supports routine screening of adolescents for gonorrhea and chlamydia, including those youth from socioeconomically disadvantaged backgrounds. Because individuals from such backgrounds may not regularly interact with traditional clinical health care systems, screening and treatment should be offered in alternative settings, such as the job training program described in this study.

Tuberculin skin testing among economically disadvantaged youth in a federally funded job training program.

Low income, medically underserved communities are at increased risk for tuberculosis. Limited population-based national data are available about tuberculous infection in young people from such backgrounds. To determine the prevalence of a positive tuberculin skin test among economically disadvantaged youth in a federally funded job training program during 1995 and 1996, the authors evaluated data from medical records of 22,565 randomly selected students from over 100 job training centers throughout the United States. An estimated 5.6% of students had a documented positive skin test or history of active tuberculosis. Rates were highest among those who were racial/ethnic minorities, foreign born, and (among foreign-born students) older in age (p < 0.001). Weighted rates (adjusting for sampling) were 1.3% for white, 2.2% for Native American, 4.0% for black, 9.6% for Hispanic, and 40.7% for Asian/Pacific Islander students; rates were 2.4% for US-born and 32.7% for foreign-born students. Differences by geographic region of residence were not significant after adjusting for other demographic factors. Tuberculin screening of socioeconomically disadvantaged youth such as evaluated in this study provides important sentinel surveillance data concerning groups at risk for tuberculous infection and allows recommended public health interventions to be offered.

HIV infection in disadvantaged out-of-school youth: prevalence for U.S. Job Corps entrants, 1990 through 1996.

To describe HIV infection prevalence and prevalence trends for disadvantaged out-of-school youth in the United States, we analyzed the HIV prevalence for and demographic characteristics of youth, aged 16 through 21 years, who entered the U.S. Job Corps from January 1990 through December 1996. Job Corps is a federally funded jobs training program for socially and economically disadvantaged out-of-school youth. All 357,443 entrants residing at Job Corps centers during their training were tested for HIV infection; 822 (2.3 per 1000) were HIV-positive. HIV prevalence was higher for women than for men (2.8 per 1000 versus 2.0 per 1000; relative risk [RR]=1.4; 95% confidence interval [CI]=1.2-1.6). Among racial/ethnic groups, prevalence was highest for African Americans (3.8 per 1000). Prevalence was higher for African American women (4.9 per 1000) than for any other gender and racial/ethnic group. From 1990 through 1996, standardized HIV prevalence-stratified by age, race/ethnicity, home region, population of home metropolitan statistical area, and year of entry--declined for women and for men: for women, from 4.1 per 1000 in 1990 to 2.1 per 1000 in 1996 (p=.001); and for men, from 2.8 per 1000 in 1990 to 1.4 per 1000 in 1996 (p=.001). These data suggest that HIV prevalence for disadvantaged out-of-school youth declined from 1990 through 1996. However, considering their youth, prevalence was still high, particularly for women and African Americans, most notably African American women. These data support the need for ongoing HIV prevention programs targeting such youth.

A dissociation in the effects of study modality on tests of implicit and explicit memory.

Three experiments investigated variables affecting explicit and implicit memory for study modality. Explicit memory for modality was compared with implicit memory for modality (modality-specific priming) following the study manipulation of modality and level of processing. Explicit recall of modality showed the same pattern of dissociations that has been observed between other measures of episodic memory and priming measures of memory. Manipulations of meaning at study that facilitated recognition and fragment-cued recall increased the accuracy of modality recall, but had no effect on primed fragment-completion performance. In contrast, changing modality between study and test affected fragment-cued performance, but had no effect on recognition or on modality recall. Successive tests of fragment-cued recall and modality recall were found to be highly dependent, whereas successive tests of fragment-completion and modality recall were essentially independent. The results are interpreted as evidence that (1) factors relevant to episodic memory of modality are unrelated to factors that produce modality-specific priming and (2) episodic memory for incidental attributes of an episode, such as modality of study, interacts with and is dependent upon memory for the episode as a whole.

Abnormal glycine betaine content of the blood and urine of diabetic and renal patients.

In normal human plasma the concentrations of the renal osmolyte, glycine betaine, are usually between 20 and 70 mumol/l, in adult males (median 44 mumol/l) higher than in females (34 mumol/l). Concentrations are lower in renal disease (median 28 mumol/l) and normal in diabetes. Urinary excretion of glycine betaine shows no sex difference and is frequently elevated both in renal disease and in diabetes (medians: normal, 6.2, renal 12.3 and diabetes, 39.7 mmol/mol creatinine). The elevation in diabetes does not strongly correlate with known renal disease, nor with either urinary microalbumin or plasma creatinine. There is no correlation with glycated haemoglobin. The positive correlation with the excretions of another renal osmolyte, sorbitol, was highly significant in diabetic subjects. In the diabetic group there was also a significant negative correlation between plasma glycine betaine and urine microalbumin.

Glycine betaine and proline betaine in human blood and urine.

In healthy human subjects, glycine betaine concentrations in the blood plasma are normally between 20 and 60 mumol/l, adult males tending to have higher concentrations than females. Proline betaine concentrations are more variable, ranging from undetectable to about 50 mumol/l. Both betaines are present in urine. Whereas the urinary excretion of proline betaine reflects plasma concentrations, with high clearance rates, there is no correlation between plasma and urine glycine betaine concentrations. The apparent clearance rates are low (usually less than 5%). The proline betaine content of human kidney tissue is less than 0.1% of the glycine betaine content, and this is true also of rabbit tissue despite high concentrations of both betaines in rabbit circulation and urine. These data suggest that glycine betaine, but not proline betaine, is important in human and other mammalian biochemistry.

Relationship between osmoprotection and the structure and intracellular accumulation of betaines by Escherichia coli.

Naturally occurring betaines, especially glycine betaine and proline betaine, were accumulated by Escherichia coli from urine. In synthetic hyperosmotic medium, with an homologous series of added betaines, (CH3)3N(+)-(CH2)n-COO-, osmoprotective activity and intracellular accumulation decreased monotonically as n increased from 1 to 5. In contrast, alpha-substituted glycine betaines were accumulated in a similar manner to glycine betaine, but with different osmoprotective activities. Arsenobetaine, with a quaternary arsonium group, was also accumulated but amino acids which can become negatively charged in a chemically basic environment were not.

Trends in HIV prevalence among disadvantaged youth. Survey results from a national job training program, 1988 through 1992.

OBJECTIVE: To describe trends in the prevalence of human immunodeficiency virus (HIV) among socially and educationally disadvantaged US youth. DESIGN: Analysis of demographic and geographic trends of HIV infection among Job Corps students from January 1988 through December 1992. SETTING: The Job Corps is a national training program for disadvantaged and out-of-school youth. POPULATION SCREENED: Youths aged 16 to 21 years who entered the Job Corps residential training centers during the survey period. MAIN OUTCOME MEASURE: Trends in prevalence of HIV infection among Job Corps students stratified by sex, age, race, and region of the country. RESULTS: Of the 269,956 Job Corps students screened, 812 (0.3%) tested positive for the antibody to HIV type 1. Seroprevalence of HIV for young men decreased from 3.6 per 1000 in 1988 to 2.2 per 1000 in 1992 (chi 2 test for trend, P < .001). Seroprevalence for young women increased from 2.1 per 1000 in 1988 to 4.2 per 1000 in 1990 (P = .001), with seroprevalence remaining stable from 1990 through 1992. The decreasing trends in HIV prevalence among men and increasing trends among women were primarily due to changes in seroprevalence in African-American students. CONCLUSIONS: The overall prevalence of HIV infection of three per 1000 is high, given the youth of Job Corps students. The significant rise in HIV rates among female Job Corps students provides evidence of the increasing risk of infection for socioeconomically disadvantaged young women. Reasons for the declining trend in HIV prevalence among male Job Corps students are not clear. Efforts to prevent the spread of HIV infection among adolescents must focus on the group that is hardest to reach--out-of-school and impoverished youth.

The role of repetition and associative interference in new semantic learning in amnesia: a case experiment.

Abstract The question of whether globally amnesic subjects can learn new semantic (factual) information is controversial. Some students of amnesia believe that they can, others that they cannot. In this article we report an extensive experiment conducted with the amnesic patient K.C. in which we examined the role of repetition and associative interference in his learning of new semantic information. In the course of 8 study sessions distributed over 4 weeks, we taught K.C. novel, amusing definitions of 96 target words (e.g., "a talkative featherbrain-PARAKEET"). We varied systematically the degree of both pre-experimental and intraexperimental associative interference, as well as the amount of study. The results of the experiment showed that K.C. can learn new semantic knowledge, and retain it over a period as long as 30 months indistinguishably from control subjects. The results further showed that the efficacy of such learning depends critically on both repetition of the material and the absence, or minimization, of pre-experimental and intraexperimental associative interference. These findings suggest that the extent to which at least some amnesic patients can acquire and retain new semantic knowledge depends on the conditions under which learning occurs, and that unqualified statements regarding the deficiency or absence of such learning in amnesia are not justified.

Same-day batch measurement of glycine betaine, carnitine, and other betaines in biological material.

Glycine betaine, carnitine, carnitine esters, butyrobetaine, and proline betaine (stachydrine) concentrations in biological materials can be reliably measured in 100-microliters samples, with a detection limit below 1 mumol/liter. The procedure is suitable for batches of more than 30 specimens and it is possible to obtain a single result within 2 h. The betaines are extracted into an acetonitrile:methanol mixture, dried with anhydrous disodium hydrogen phosphate containing argentous oxide. The 4-bromophenacyl ester derivatives are formed using 4-bromophenacyl triflate as reagent, in the presence of solid magnesium oxide as base. The derivatives are separated by high-performance chromatography on a silica column, in a mixed partition and ion-exchange mode.

Human immunodeficiency virus infection in disadvantaged adolescents. Findings from the US Job Corps.

UNLABELLED: OBJECTIVE--To describe the human immunodeficiency virus (HIV) epidemic among socially and educationally disadvantaged young persons in the United States. DESIGN: -We analyzed demographic and geographic findings from the screening of Job Corps students for antibody to HIV. SETTING--The Job Corps is a federal training program for disadvantaged, out-of-school youth. POPULATION SCREENED--Residential students aged 16 to 21 years who entered the Job Corps from October 1987 through February 1990. MAIN OUTCOME MEASURE--Rates of observed HIV infection in entering students, stratified by demographic and geographic features. RESULTS--Of 137,209 Job Corps students screened, 488 were HIV seropositive (3.6 per 1000), a seroprevalence rate higher than that among military applicants of the same age. Overall seroprevalence was slightly higher in male (3.7 per 1000) than in female (3.2 per 1000) Job Corps students, but among those students aged 16 and 17 years, seroprevalence was higher among females (2.3 per 1000) than among males (1.5 per 1000) (P less than .05). For students aged 16 to 21 years, seroprevalence increased with year of age: 1.8 per 1000 per year for males and 0.7 per 1000 per year for females. Among those aged 21 years, HIV prevalence was 8.9 per 1000. For black and Hispanic students from large Northeastern cities, seroprevalence increased by 4.3 per 1000 per year of age and reached 24.8 per 1000 (one of 40) in students aged 21 years. However, among students from rural areas and small towns, HIV seroprevalence was disproportionately high in the Southeast. Compared with recently described US patients with the acquired immunodeficiency syndrome, HIV-infected students who entered the Job Corps were much more likely to be female. CONCLUSIONS--These findings show that disadvantaged, out-of-school adolescents are at high risk for HIV infection. The screening results identified surprisingly high seroprevalence in the southeastern United States and demonstrated a marked shift in the HIV epidemic to young women. Controlling the HIV epidemic among teenagers must include interventions that will reach adolescents early and outside of the formal educational system.

Long-lasting perceptual priming and semantic learning in amnesia: a case experiment.

An investigation of perceptual priming and semantic learning in the severely amnesic subject K.C. is reported. He was taught 64 three-word sentences and tested for his ability to produce the final word of each sentence. Despite a total lack of episodic memory, he exhibited (a) strong perceptual priming effects in word-fragment completion, which were retained essentially in full strength for 12 months, and (b) independent of perceptual priming, learning of new semantic facts, many of which were also retained for 12 months. K.C.'s semantic learning may be at least partly attributable to repeated study trials and minimal interference during learning. The findings suggest that perceptual priming and semantic learning are subserved by two memory systems different from episodic memory and that both systems (perceptual representation and semantic memory) are at least partially preserved in some amnesic subjects.

Contingent dissociation between recognition and fragment completion: the method of triangulation.

Two experiments conforming to the logic of the method of triangulation were conducted. Following the study of a list of words, the first of two successive tests (recognition) was identical for two groups of subjects, but the second one, in which the same word-fragment cues were presented to both groups, differed with respect to retrieval instructions. Subjects in one group engaged in cued recall of study-list words, whereas those in the second group completed the fragments with the first word that came to mind. Both experiments yielded the same result: The dependency between the first and second tests, indexed by Yule's Q statistic, was greater for recognition and cued recall than it was for recognition and fragment completion. These results speak to the controversial issue of the usefulness of contingency analyses of data from successive memory tests. The results are interpreted in a theoretical framework consisting of an integration of the idea of a hypothetical quasi-memory system with the transfer-appropriate procedural approach.

Specific word transfer as a measure of processing in the word-superiority paradigm.

Explanations of context effects in the Reicher-Wheeler task and the letter-identification task appeal to word-based processing, yet these tasks provide no explicit measure of word processing. An experiment is reported which was designed to investigate the use of transfer in the word-identification task as a measure of word-based processing in letter-identification tasks. It was found that encoding manipulations that determined whether a word-superiority effect was or was not found in a letter-identification task (e.g., Thompson & Massaro, 1973) also determined whether transfer was or was not found in a subsequent word-identification task. The results of the experiment are discussed in terms of the utility of using transfer experiments as converging evidence about the presence and/or absence of processes that cannot be directly measured in other experimental paradigms.

Low-pressure, metastable growth of diamond and "diamondlike" phases.

Diamond may be grown at low pressures where it is the metastable form of carbon. Recent advances in a wide variety of plasma and electrical discharge methods have led to dramatic increases in growth rates. All of these methods have certain aspects in common, namely, the presence of atomic hydrogen and the production of energetic carbon-containing fragments under conditions that support high mobilities on the diamond surface. Some understanding of the processes taking place during nucleation and growth of diamond has been achieved, but detailed molecular mechanisms are not yet known. Related research has led to the discovery of a new class of materials, the "diamondlike" phases. Vapor-grown diamond and diamondlike materials may have eventual applications in abrasives, tool coatings, bearing surfaces, electronics, optics, tribological surfaces, and corrosion protection.

Pathology and glutathione status in 3-methylindole-treated rodents.

Light and electron microscopic studies were performed to assess the pathology induced by 3-methylindole (3MI) in Sprague-Dawley rats and Swiss-Webster mice. Rats have not been established as a susceptible species to 3MI-induced pulmonary damage, whereas mice are known to be a good model for this pneumotoxicity. Therefore, mice were used as a comparison species for pneumotoxicity studies in the rat. Rats were as susceptible to 3MI-mediated toxicity as mice. The loss of Clara cells in the bronchiolar epithelium was the major pulmonary lesion in both species. Alveolar cells in the lungs of either species were not damaged. The only other lesion in the rat was that the nasal epithelium was totally eroded in caudal areas of the sinuses. Glutathione was depleted by 3MI in pulmonary tissues of mice and rats. Maximal depletion (53% of control values) occurred in rat lung. This work demonstrates that both rodent species are susceptible to 3MI-induced pulmonary damage.

Health status of disadvantaged adolescents entering the Job Corps program.

The health status of 2,203 disadvantaged young people entering the Job Corps was studied by reviewing the medical information collected during examinations performed upon entering the Job Corps. The study was conducted from February 1980 through January 1981. The sample records were obtained from eight representative Job Corps centers. The Job Corps is a federally funded residential vocational training program for youths between 16 and 22 years of age. During the study period, 100 Job Corps centers were in operation, serving a population of 38,000 corpsmembers. Long-term, chronic physical disease or disability was not prevalent among the applicants. The most common physical defect, affecting 10 percent of the youths examined, was uncorrected defective visual acuity. Obesity, defined as weight for height 20 percent or more over nationally calculated "desirable" weights, was present in 16.6 percent of the female trainees. In contrast, only 9.6 percent of a national sample of females have weights this high. Anemia, probably caused by iron deficiency, was prevalent among both sexes; sexually transmitted diseases were found to be common, especially among the females entering the Job Corps. Findings from this study were used by Job Corps staff to make changes in the health program as well as to provide instruction to its health personnel.