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951.
The Cham people are the major Austronesian speakers of Mainland Southeast Asia (MSEA) and the reconstruction of the Cham population history can provide insights into their diffusion. In this study, we analyzed non-recombining region of the Y chromosome markers of 177 unrelated males from four populations in MSEA, including 59 Cham, 76 Kinh, 25 Lao, and 17 Thai individuals. Incorporating published data from mitochondrial DNA (mtDNA), our results indicated that, in general, the Chams are an indigenous Southeast Asian population. The origin of the Cham people involves the genetic admixture of the Austronesian immigrants from Island Southeast Asia (ISEA) with the local populations in MSEA. Discordance between the overall patterns of Y chromosome and mtDNA in the Chams is evidenced by the presence of some Y chromosome lineages that prevail in South Asians. Our results suggest that male-mediated dispersals via the spread of religions and business trade might play an important role in shaping the patrilineal gene pool of the Cham people.  相似文献   
952.
HemaMax, a recombinant human interleukin-12 (IL-12), is under development to address an unmet medical need for effective treatments against acute radiation syndrome due to radiological terrorism or accident when administered at least 24 hours after radiation exposure. This study investigated pharmacokinetics, pharmacodynamics, and efficacy of m-HemaMax (recombinant murine IL-12), and HemaMax to increase survival after total body irradiation (TBI) in mice and rhesus monkeys, respectively, with no supportive care. In mice, m-HemaMax at an optimal 20 ng/mouse dose significantly increased percent survival and survival time when administered 24 hours after TBI between 8-9 Gy (p<0.05 Pearson's chi-square test). This survival benefit was accompanied by increases in plasma interferon-γ (IFN-γ) and erythropoietin levels, recovery of femoral bone hematopoiesis characterized with the presence of IL-12 receptor β2 subunit-expressing myeloid progenitors, megakaryocytes, and osteoblasts. Mitigation of jejunal radiation damage was also examined. At allometrically equivalent doses, HemaMax showed similar pharmacokinetics in rhesus monkeys compared to m-HemaMax in mice, but more robustly increased plasma IFN-γ levels. HemaMax also increased plasma erythropoietin, IL-15, IL-18, and neopterin levels. At non-human primate doses pharmacologically equivalent to murine doses, HemaMax (100 ng/Kg and 250 ng/Kg) administered at 24 hours after TBI (6.7 Gy/LD(50/30)) significantly increased percent survival of HemaMax groups compared to vehicle (p<0.05 Pearson's chi-square test). This survival benefit was accompanied by a significantly higher leukocyte (neutrophils and lymphocytes), thrombocyte, and reticulocyte counts during nadir (days 12-14) and significantly less weight loss at day 12 compared to vehicle. These findings indicate successful interspecies dose conversion and provide proof of concept that HemaMax increases survival in irradiated rhesus monkeys by promoting hematopoiesis and recovery of immune functions and possibly gastrointestinal functions, likely through a network of interactions involving dendritic cells, osteoblasts, and soluble factors such as IL-12, IFN-γ, and cytoprotectant erythropoietin.  相似文献   
953.
954.

Background

Survivors of physical and emotional trauma experience enduring occupational, psychological and quality of life impairments. Examining survivors from a large fire provides a unique opportunity to distinguish the impact of physical and emotional trauma on long-term outcomes. The objective is to detail the multi-dimensional long-term effects of a large fire on its survivor population and assess differences in outcomes between survivors with and without physical injury.

Methods and Findings

This is a survey-based cross-sectional study of survivors of The Station fire on February 20, 2003. The relationships between functional outcomes and physical injury were evaluated with multivariate regression models adjusted for pre-injury characteristics and post-injury outcomes. Outcome measures include quality of life (Burn Specific Health Scale–Brief), employment (time off work), post-traumatic stress symptoms (Impact of Event Scale–Revised) and depression symptoms (Beck Depression Inventory). 104 fire survivors completed the survey; 47% experienced a burn injury. There was a 42% to 72% response rate range. Although depression and quality of life were associated with burn injury in univariate analyses (p<0.05), adjusted analyses showed no significant relationship between burn injury and these outcomes (p = 0.91; p = .51). Post-traumatic stress symptoms were not associated with burn injury in the univariate (p = 0.13) or adjusted analyses (p = 0.79). Time off work was the only outcome in which physical injury remained significant in the multivariate analysis (p = 0.03).

Conclusions

Survivors of this large fire experienced significant life disruption, including occupational, psychological and quality of life sequelae. The findings suggest that quality of life, depression and post-traumatic stress outcomes are related to emotional trauma, not physical injury. However, physical injury is correlated with employment outcomes. The long-term impact of this traumatic event underscores the importance of longitudinal and mental health care for trauma survivors, with attention to those with and without physical injuries.  相似文献   
955.
Six strains of lactobacilli belonging to three species (Lactobacillus casei, Lactobacillus acidophilus and Lactobacillus helveticus) were evaluated for probiotic attributes viz. acid tolerance, bile tolerance and cell surface hydrophobicity. All the six strains exhibited probiotic attributes with considerable degree of variation. Three Lactobacillus strains selected on the basis of probiotic attributes were used for preparing three different fermented milks. In order to evaluate the effect of feeding these probiotic fermented milks on macrophage cell function, an in-vivo trial was conducted in mice for a period of 2, 5 and 8?days. The control group of mice was fed with skim milk. The phagocytic activity of macrophages increased significantly (P?<?0.05) on feeding fermented milk prepared using L. acidophilus, L. casei and L. helveticus as compared to milk group (control) on 2nd, 5th and 8th day of feeding, respectively. Likewise, the release of ??-glucuronidase and ??-galactosidase from peritoneal macrophages increased significantly (P?<?0.05) on 2nd, 5th and 8th day of feeding as compared to their respective control group (milk). The results thus depict that feeding of probiotic fermented milk enhances phagocytic activity of the macrophages.  相似文献   
956.
From the MeOH extract of the leaves of Artocarpus altilis (Moraceae), three new aurones, altilisin H (1), I (2), and J (3), have been isolated together with two known flavonoids. Their structures were elucidated on the basis of spectroscopic data. All compounds possessed tyrosinase inhibitory activity with IC50 values less than 100 μM, while compounds 13 displayed potent α-glucosidase inhibitory activity with IC50 values ranging from 4.9 to 5.4 μM.  相似文献   
957.

Background

Knowledge, clinical practice, and professional motivation of medical providers relating to H5N1 infection have an important influence on care for H5N1 patients who require early diagnosis and early medical intervention.

Methods/Principal Findings

Novel educational programs including training and workshops for medical providers relating to H5N1 infection in Vietnam were originally created and implemented in 18 provincial hospitals in northern Vietnam between 2008 and 2010. A self-administered, structured questionnaire survey was conducted in 8 provincial hospitals where both educational training and workshops were previously provided. A total of 326 medical providers, including physicians, nurses, and laboratory technicians who attended or did not attend original programs were enrolled in the survey. Knowledge, clinical attitudes and practice (KAP), including motivation surrounding caring for H5N1 patients, were evaluated. The study indicated a high level of knowledge and motivation in all professional groups, with especially high levels in laboratory technicians. Conferences and educational programs were evaluated to be the main scientific information resources for physicians, along with information from colleagues. The chest radiographs and the initiation of antiviral treatment in the absence of RT-PCR result were identified as gaps in education. Factors possibly influencing professional motivation for caring for H5N1 patients included healthcare profession, the hospital where the respondents worked, age group, attendance at original educational programs and at educational programs which were conducted by international health-related organizations.

Conclusions

Educational programs provide high knowledge and motivation for medical providers in Vietnam caring for H5N1 patients. Additional educational programs related to chest radiographs and an initiation of treatment in the absence of RT-PCR are needed. Networking is also necessary for sharing updated scientific information and practical experiences. These enhanced KAPs by educational programs and integrated systems among hospitals should result in appropriate care for H5N1 patients and may reduce morbidity and mortality.  相似文献   
958.
959.
The species B human adenoviruses (HAdVs) infect cells upon attaching to CD46 or desmoglein 2 (DSG-2) by one or several of their 12 fiber knob trimers (FKs). To test whether DSG-2 and CD46 simultaneously serve as virus receptors for adenovirus type 3 (Ad3), we performed individual and combined CD46/DSG-2 loss-of-function studies in human lung A549 and 16HBE14o cells. Our results suggest that in these cells, DSG-2 functions as a major attachment receptor for Ad3, whereas CD46 exerts a minor contribution to virus attachment and uptake in the range of ~10%. However, in other cells the role of CD46 may be more pronounced depending on, e.g., the expression levels of the receptors. To test if avidity allows Ad3/7 to use CD46 as a receptor, we performed gain-of-function studies. The cell surface levels of ectopically expressed CD46 in CHO or human M010119 melanoma cells lacking DSG-2 positively correlated with Ad3/7 infections, while Ad11/35 infections depended on CD46 but less on CD46 levels. Antibody-cross-linked soluble CD46 blocked Ad3/7/11/35 infections, while soluble CD46 alone blocked Ad11/35 but not Ad3/7. Soluble Ad3/7-FKs poorly inhibited Ad3/7 infection of CHO-CD46 cells, illustrating that Ad3/7-FKs bind with low affinity to CD46. This was confirmed by Biacore studies. Ad3/7-FK binding to immobilized CD46 at low density was not detected, unlike that of Ad11/35-FK. At higher CD46 densities, however, Ad3/7-FK bound to CD46 with only 15-fold-higher dissociation constants than those of Ad11/35-FK. These data show that an avidity mechanism for Ad3/7 binding to CD46 leads to infection of CD46-positive cells.  相似文献   
960.
To better understand the qualitative features of effective human immunodeficiency virus (HIV)-specific immunity, we examined the TCR clonal composition of CD8(+) T cells recognizing conserved HIV p24-derived epitopes in HLA-B*5701-positive long-term nonprogressors/elite controllers (LTNP/EC) and HLA-matched progressors. Both groups displayed oligoclonal HLA-B5701-restricted p24-specific CD8(+) T-cell responses with similar levels of diversity and few public clonotypes. Thus, HIV-specific CD8(+) T-cell responses in LTNP/EC are not differentiated from those of progressors on the basis of clonal diversity or TCR sharing.  相似文献   
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