Regret and psychological well-being among voluntarily and involuntarily childless women and mothers

This study examines regret and psychological well-being among 72 middle-aged and older women who are either voluntarily childless, involuntarily childless, or mothers. Group comparisons indicate that, when compared to involuntarily childless women, voluntarily childless women show higher levels of overall well-being, rate themselves as more autonomous with greater environmental mastery, and are less likely to have a child-related regret. An unexpected finding is that about one-third of women categorized by researchers as involuntarily childless indicate that they are "childless by choice." These women report making an active decision to accept the childless lifestyle and focus on the future, in essence exerting control over their situations. Results from this small and selective sample should be interpreted cautiously. However, they do suggest that researchers' definitions of childlessness may not map directly onto those of participants, and they emphasize the importance of ascertaining respondents' perceptions of control over their situations.     

Outbreak of pertussis among healthcare workers in a hospital surgical unit.

BACKGROUND: In September 1999, a pertussis outbreak was detected among surgical staff of a 138-bed community hospital. Patients were exposed to Bordetella pertussis during the 3-month outbreak period. OBJECTIVE: To describe the outbreak among surgical staff, to evaluate implemented control measures, and to determine whether nosocomial transmission occurred. METHODS: Clinical pertussis was defined as acute cough illness with a duration of 14 days or more without another apparent cause; persons with positive culture, PCR, or serologic test results were defined as having laboratory-confirmed pertussis. Surgical healthcare workers (HCWs) were interviewed regarding pertussis symptoms, and specimens were obtained for laboratory analysis. Patients exposed to B. pertussis during an ill staff member's 3-week infectious period were interviewed by phone to determine the extent of nosocomial spread. PARTICIPANTS: A total of 53 HCWs assigned to the surgical unit and 146 exposed patients. HCWs with pertussis were defined as case subjects; HCWs without pertussis were defined as non-case subjects. RESULTS: Twelve (23%) of 53 HCWs had clinical pertussis; 6 cases were laboratory confirmed. The median cough duration in the 12 case subjects was 27 days (range, 20-120 days); 10 (83%) had paroxysms. Eleven (92%) of 12 case subjects and 28 (86%) of 41 non-case subjects received antibiotic treatment or prophylaxis. Seven case subjects (58%) reported they always wore a mask when near patients. Of 146 patients potentially exposed to pertussis from the 12 case subjects, 120 (82%) were interviewed; none reported a pertussis-like illness. CONCLUSIONS: Surgical staff transmitted B. pertussis among themselves; self-reported data suggests that these HCWs did not transmit B. pertussis to their patients, likely because of mask use, cough etiquette, and limited face-to-face contact. Control measures might have helped limit the outbreak once pertussis was recognized.     

Developmental role of static, dynamic, and contextual cues in speech perception.

The purpose of the current study was to examine the role of syllable duration context as well as static and dynamic acoustic properties in child and adult speech perception. Ten adults and eleven 4-5-year-old children identified a syllable as [ba] or [wa] (stop-glide contrast) in 3 conditions differing in synthetic continua. The 1st condition tested the potential existence of the syllable duration effect in young children, whereas the 2nd and 3rd conditions examined the developmental role of static and dynamic cues, respectively, as related to syllable duration context effects. In the 1st condition, the 1st and 2nd formant transition duration of stimuli varied from those appropriate for [ba] to those appropriate for [wa]. For the 2nd condition, a static burst was added to Condition 1 stimuli. For the 3rd condition, the dynamic transition frequency and transition duration for the first 3 formants varied as appropriate for [ba] and [wa]. In each condition, 3 syllable context durations of 105 ms, 170 ms, and 315 ms were tested. The results indicated that syllable duration context effects were present across all conditions for both adults and children. However, the adults and children did differ in the 3rd condition, in which both the transition frequency and the transition duration were altered. Thus, children used the dynamic formant transitions differently than adults when transition frequency was varied along with transition duration. These findings show that children have a bias toward formant transitions and indicate that young children of 4-5 years of age attend differently than adults to changes in dynamic cues such as formant transitions, as predicted by the developmental cue weighting shift model.     

Listening effort and fatigue in school-age children with and without hearing loss.

Parents, audiologists, and educators have long speculated that children with hearing loss must expend more effort and, therefore, fatigue more easily than their peers with normal hearing when listening in adverse acoustic conditions. Until now, however, very few studies have been conducted to substantiate these speculations. Two experiments were conducted with school-age children with mild-to-moderate hearing loss and with normal hearing. In the first experiment, salivary cortisol levels and a self-rating measure were used to measure fatigue. Neither cortisol measurements nor self-rated measures of fatigue revealed significant differences between children with hearing loss and their normal-hearing peers. In the second experiment, however, a dual-task paradigm used to study listening effort indicated that children with hearing loss expend more effort in listening than children with normal hearing. Results are discussed in terms of clinical application and future research needs.     

Chemokine receptor-5 (CCR5) is a receptor for the HIV entry inhibitor peptide T (DAPTA)

The chemokine receptor CCR5 plays a crucial role in transmission of HIV isolates, which predominate in the early and middle stages of infection, as well as those, which populate the brain and cause neuro-AIDS. CCR5 is therefore an attractive therapeutic target for design of entry inhibitors. Specific rapid filtration binding assays have been useful for almost 30 years both for drug discovery and understanding molecular mechanisms of drug action. Reported in 1986, prior to discovery of chemokine co-receptors and so thought to act at CD4, peptide T (DAPTA) appears to greatly reduce cellular viral reservoirs in both HAART experienced and treatment na?ve patients, without toxicities. We here report that DAPTA potently inhibits specific CD4-dependent binding of gp120 Bal (IC50=0.06 nM) and CM235 (IC50=0.32 nM) to CCR5. In co-immunoprecipitation studies, DAPTA (1 nM) blocks formation of the gp120/sCD4 complex with CCR5. Confocal microscopic studies of direct FITC-DAPTA binding to CCR5+, but not CCR5-, cells show that CCR5 is a DAPTA receptor. The capability of DAPTA to potently block gp120-CD4 binding to the major co-receptor CCR5 explains its molecular and therapeutic mechanism of action as a selective antiviral entry inhibitor for R5 tropic HIV-1 isolates.     

Bullying and symptoms among school-aged children: international comparative cross sectional study in 28 countries

BACKGROUND: There have been no large-scale international comparisons on bullying and health among adolescents. This study examined the association between bullying and physical and psychological symptoms among adolescents in 28 countries. METHODS: This international cross-sectional survey included 123,227 students 11, 13 and 15 years of age from a nationally representative sample of schools in 28 countries in Europe and North America in 1997-98.The main outcome measures were physical and psychological symptoms. RESULTS: The proportion of students being bullied varied enormously across countries. The lowest prevalence was observed among girls in Sweden (6.3%, 95% CI: 5.2-7.4), the highest among boys in Lithuania (41.4%, 95% CI 39.4-43.5). The risk of high symptom load increased with increasing exposure to bullying in all countries. In pooled analyses, with sex stratified multilevel logistic models adjusted for age, family affluence and country the odds ratios for symptoms among students who were bullied weekly ranged from 1.83 (95% CI 1.70-1.97) to 2.11 (95% CI 1.95-2.29) for physical symptoms (headache, stomach ache, backache, dizziness) and from 1.67 (95% CI 1.55-1.78) to 7.47 (95% CI 6.87-8.13) for psychological symptoms (bad temper, feeling nervous, feeling low, difficulties in getting to sleep, morning tiredness, feeling left out, loneliness, helplessness). CONCLUSION: There was a consistent, strong and graded association between bullying and each of 12 physical and psychological symptoms among adolescents in all 28 countries.     

Diarrheal illnesses: a public health perspective

Diarrheal illnesses remain among the leading causes of morbidity in the United States. Approximately five million diarrheal cases occur annually (Chin, 2000; Ostroff & Leduc, 2000), with an estimated incidence of one diarrheal episode per person per year (Aranda-Michel & Giannella, 1999). Though the causes of diarrheal illnesses vary, infectious agents account for a majority of cases (Aranda-Michel & Giannella, 1999; Chin, 2000; Ostroff & Leduc, 2000). Most diarrhea-causing infectious agents are transmitted through food, water, or person-to-person via the fecal-oral route and are the cause of numerous diarrheal outbreaks. The risk for exposure to such pathogens within the general population is universal; however, persons in pediatric, geriatric, and other immunocompromised populations are at increased risk for subsequent illness and complications (Centers for Disease Control and Prevention, 2001; Ostroff & Leduc, 2000). Moreover, many persons with diarrheal illness do not seek medical care and self-treat with over-the-counter antidiarrheal agents, which have potentially serious side effects among high-risk individuals. The public health impact of diarrheal illness is apparent and emphasizes the need for early diagnosis and appropriate treatment, timely notification of illness with public health implications, and coordination between healthcare professionals and public health officials to prevent and control the spread of infection.     

Methodologic and statistical approaches to studying human fertility and environmental exposure

Although there has been growing concern about the effects of environmental exposures on human fertility, standard epidemiologic study designs may not collect sufficient data to identify subtle effects while properly adjusting for confounding. In particular, results from conventional time to pregnancy studies can be driven by the many sources of bias inherent in these studies. By prospectively collecting detailed records of menstrual bleeding, occurrences of intercourse, and a marker of ovulation day in each menstrual cycle, precise information on exposure effects can be obtained, adjusting for many of the primary sources of bias. This article provides an overview of the different types of study designs, focusing on the data required, the practical advantages and disadvantages of each design, and the statistical methods required to take full advantage of the available data. We conclude that detailed prospective studies allowing inferences on day-specific probabilities of conception should be considered as the gold standard for studying the effects of environmental exposures on fertility.     

Variable modulation of opioid brain uptake by P-glycoprotein in mice

The efflux transporter P-glycoprotein (P-gp) is an important component of the blood-brain barrier (BBB) that limits accumulation of many compounds in brain. Some opioids have been shown to interact with P-gp in vitro and in vivo. Genetic or chemical disruption of P-gp has been shown to enhance the antinociceptive and/or toxic effects of some opioids, although the extent of this phenomenon has yet to be understood. The purpose of this study was to assess quantitatively the influence of mdr1a P-gp on initial brain uptake of chemically diverse opioids in mice. The brain uptake of opioids selective for the mu (fentanyl, loperamide, meperidine, methadone, and morphine), delta (deltorphin II, DPDPE, naltrindole, SNC 121) and kappa (bremazocine and U-69593) receptor subtypes was determined in P-gp-competent (wild-type) and P-gp-deficient [mdr1a(-/-)] mice with an in situ brain perfusion model. BBB permeability of the opioids varied by several orders of magnitude in both mouse strains. The difference in brain uptake between P-gp-competent and P-gp-deficient mice ranged from no detectable effect (meperidine) to >/=8-fold increase in uptake (DPDPE, loperamide, and SNC 121). In addition, loperamide efflux at the BBB was inhibited by quinidine. These results demonstrate that P-gp modulation of opioid brain uptake varies substantially within this class of compounds, regardless of receptor subtype. P-gp-mediated efflux of opioids at the BBB may influence the onset, magnitude, and duration of analgesic response. The variable influence of P-gp on opioid brain distribution may be an important issue in the context of pharmacologic pain control and drug interactions.