Poor sleep quality, antepartum depression and suicidal ideation among pregnant women.

To evaluate the independent and combined associations of maternal self-reported poor sleep quality and antepartum depression with suicidal ideation during the third trimester METHODS: A cross-sectional study was conducted among 1298 pregnant women (between 24 and 28 gestational weeks) attending prenatal clinics in Lima, Peru. Antepartum depression and suicidal ideation were assessed using the Patient Health Questionnaire-9 (PHQ-9). The Pittsburgh Sleep Quality Index (PSQI) questionnaire was used to assess sleep quality. Multivariate logistical regression procedures were used to estimate odds ratios (OR) and 95% confidence intervals (95% CI) after adjusting for putative confounders. Approximately, 17% of women were classified as having poor sleep quality (defined using the recommended criteria of PSQI global score of >5 vs. ≤5). Further, the prevalence of antepartum depression and suicidal ideation were 10.3% and 8.5%, respectively in this cohort. After adjusting for confounders including depression, poor sleep quality was associated with a 2.81-fold increased odds of suicidal ideation (OR=2.81; 95% CI 1.78-4.45). When assessed as a continuous variable, each 1-unit increase in the global PSQI score resulted in a 28% increase in odds for suicidal ideation, even after adjusting for depression (OR=1.28; 95% CI 1.15-1.41). The odds of suicidal ideation was particularly high among depressed women with poor sleep quality (OR=13.56 95% CI 7.53-24.41) as compared with women without either risk factor. This cross-sectional study utilized self-reported data. Causality cannot be inferred, and results may not be fully generalizable. Poor sleep quality, even after adjusting for depression, is associated with antepartum suicidal ideation. Our findings support the need to explore sleep-focused interventions for pregnant women

Assessing the Transport Properties of Organic Penetrants in Low-Density Polyethylene Using Free Volume Models

Three models, two of them relying on free volume - the Cohen-Turnbull-Fujita (CTF) model and the Vrentas-Duda (VD) model, and the third being empirical using an exponential concentration dependence of the diffusivity, were applied to desorption data for a series of alkane penetrants (2,2-dimethylbutane, cyclohexane, n-hexane, n-decane, and n-tetradecane) in low-density polyethylene. The CTF model described the desorption data very well and better than the exponential diffusion law. The VD model with the attractive feature of being based on independently determined parameters was successful in describing the desorpion data. Diffusivity data indicated that the three components outside the crystal core were less accessible to n-tetradecane than to the other penetrants. This indication was further substantiated by solubility data

FREE VOLUME AND TRANSPORT PROPERTIES OF HOMOGENEOUS POLY(ETHYLENE-CO-OCTENE)S

Liquid and vapour n-hexane sorption/desorption were studied on homogeneous poly(ethylene-co-octene)s produced by metallocenecatalyzed polymerisation covering a crystallinity range from 3.5 to 72.4%. Crystal core contents determined by Raman spectroscopy were lower than those determined by density assessments, particularly at low degrees of crystallinity. The solubility showed deviation from Henry’s law. The solubilities of n-hexane in the homogeneous copolymers depended in a non-linear manner on the content of penetrable polymer component and were lower than those earlier reported for heterogeneous copolymers at the same contents of penetrable component. The concentration dependence of the thermodynamic diffusivity predicted by the Cohen–Turnbull–Fujita free volume theory was confirmed by the data obtained by the differential method and the differences between the results obtained from the integral and differential methods were within the margins of experimental error. The fractional free volume of the penetrable polymer fraction increased with increasing fraction of penetrable polymer and with relative proportion of liquid-like component in the penetrable polymer fraction. The homogeneous copolymers showed a decreasing trend in the geometrical impedance factor with increasing degree of crystallinity

Sex and parity modulate cytokine production during murine ageing

We have previously shown that physiological hormone differences related to pregnancy or sex affect the age-related distribution of mononuclear cell populations during murine ageing. To determine whether such changes are involved in the age-related changes in functions of T cells, we examined the secretion of major T cell immunoregulatory cytokines (IL-2, IL-4, interferon-gamma (IFN-γ), IL-3, IL-6 and granulocyte-macrophage colony-stimulating factor (GM-CSF)) of in vitro concanavalin A-activated spleen cells of C57Bl/6 mice. The study included multiparous and virgin females and males at 2, 8, 15 and 23 months of age. Short-term effects of parity (8 months) were evidenced by the decrease of IFN-γ and the preserved IL-2 production in multiparous females (8 months), while IFN-γ was unchanged and IL-2 decreased in virgin mice. The increase in IL-4 production appeared earlier in multiparous females (15 months) than in virgin mice (23 months). The increase in IL-4/IFN-γ and IL-4/IL-2 ratios at 8 and 15 months, respectively, in multiparous females, suggests that pregnancy modifies the Th1/Th2 equilibrium. In late adulthood (15 months), IL-6 and GM-CSF production was higher in multiparous females than in virgin males or females. Sex differences were also noticed: IFN-γ secretion capacity was lower in males than in females during ageing. This study underlines that the onset, magnitude and kinetics of the age-related changes in cytokine production are parity- and sex-dependent. These changes probably influence the incidence of age-related diseases and may explain the greater longevity of females

Surface antigen expression in spleen cells of C57Bl/6 mice during ageing: influence of sex and parity

So far all studies on the murine ageing process have been conducted on virgin mice. Immune ageing may be influenced by sex hormone differences related to sex or pregnancies. The aim of this study was to investigate whether pregnancies and gender influence the cell changes observed during ageing in a peripheral lymphoid compartment of C57Bl/6 mice. Using flow cytometry, changes in (Thy1.2+) T cell, (B220+) B cell and (CD11b/Mac-1) macrophage spleen populations were monitored in 2, 8 (3 months after last pregnancy) 15 and 23-month-old mice including males, virgin and multiparous females. The development of naive (CDCD44low), memory (CD44high), activated/memory (MEL-14, CD62L) cells were investigated in CD4+ and CE8+ T cell subsets. Both short term (at 8 months) and long term (at 15 and 23 months) effects of multiparity were obvious in the lymphocyte/macrophage population changes associated with the ageing process. Short-term effects included delayed appearance of CD4+CD44high memory lymphocytes and increased numbers of both CD4+MEL-14low activated/memory cells and Mac-1+ macrophages when compared with virgin control mice. Later effects of multiparity were increased CD8αdull populations and increased T/B cell ratios and the ratio of memory to naive CD4+ cells (CD44+high/CD44+low). A sex effect was noticed: males exhibited lower Mac-1+ levels and memory/naive ratio in CD4+ subset than virgin females throughout life. These results suggest that gender and/or pregnancies affect the age-related distribution of lymphoid and macrophage cell populations in the spleen of C57Bl/6 mice

Pregnancies modulate B lymphopoiesis and myelopoiesis during murine ageing

We recently reported that pregnancy affects age‐related changes in the distribution of lymphoid and macrophage populations in the spleen of C57Bl/6 mice. In the present study, we examined the influence of pregnancies on the generation of various developmental B‐cell subsets and granulocyte/macrophage lineage cells during murine ageing. Using flow cytometry, changes in lymphoid (mature and early B‐cell precursors: B220high, B220low, surface immunoglobulin M (sIgM) µ chain +/−) and myeloid (monocyte/macrophage Mac‐1/CD11b, granulocyte Gr‐1/Ly‐6G) compartments were monitored in the bone marrow of young (2 months) and 15‐ and 23‐month‐old mice including male, multiparous and virgin female mice. Pregnancies delayed the age‐related decline in murine B lymphopoiesis and maintained B‐cell reserve capacity during ageing. We also found an increased production of myeloid cells induced by pregnancies at middle (15 months) and advanced (23 months) ages. This comparative study provides new information on changes in marrow lymphopoiesis and myelopoiesis with age. Our data emphasizes that the onset, magnitude and kinetics of age‐related changes in the haematopoietic marrow are parity dependent. These changes could influence the incidence of age‐related diseases and may account for the greater longevity of females