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22.
Kim J. Brolin Ribacke Alex J. van Duinen Helena Nordenstedt Jonas H?ijer Ragnhild Molnes Torunn Wigum Froseth AP Koroma Elisabeth Darj H?kon Angel Bolkan AnnaMia Ekstr?m 《PloS one》2016,11(2)
Background
As Sierra Leone celebrates the end of the Ebola Virus Disease (EVD) outbreak, we can begin to fully grasp its impact on already weak health systems. The EVD outbreak in West Africa forced many hospitals to close down or reduce their activity, either to prevent nosocomial transmission or because of staff shortages. The aim of this study is to assess the potential impact of EVD on nationwide access to obstetric care in Sierra Leone.Methods and Findings
Community health officers collected weekly data between January 2014—May 2015 on in-hospital deliveries and caesarean sections (C-sections) from all open facilities (public, private for-profit and private non-profit sectors) offering emergency obstetrics in Sierra Leone. This was compared to official data of EVD cases per district. Logistic and Poisson regression analyses were used to compute risk and rate estimates. Nationwide, the number of in-hospital deliveries and C-sections decreased by over 20% during the EVD outbreak. The decline occurred early on in the EVD outbreak and was mainly attributable to the closing of private not-for-profit hospitals rather than government facilities. Due to difficulties in collecting data in the midst of an epidemic, limitations of this study include some missing data points.Conclusions
Both the number of in-hospital deliveries and C-sections substantially declined shortly after the onset of the EVD outbreak. Since access to emergency obstetric care, like C-sections, is associated with decreased maternal mortality, many women are likely to have died due to the reduced access to appropriate care during childbirth. Future research on indirect health effects of health system breakdown should ideally be nationwide and continue also into the recovery phase. It is also important to understand the mechanisms behind the deterioration so that important health services can be reestablished. 相似文献23.
AP Shoko SM Limbu HA Lamtane MA Kishe-Machumu B Sekadende EE Ulotu 《African Journal of Aquatic Science》2019,44(1):15-24
Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system. 相似文献
24.
Minich DM Bland JS Katke J Darland G Hall A Lerman RH Lamb J Carroll B Tripp M 《Canadian journal of physiology and pharmacology》2007,85(9):872-883
In this report, we examine the clinical safety and efficacy of NG440, a phytochemical-based antiinflammatory formula consisting of a combination of rho iso-alpha acids from hops, rosemary, and oleanolic acid. In a previous study, we demonstrated that NG440 significantly decreased pain by 50% in patients with osteoarthritis. Consistent with these data, results from a multicentre trial indicate that NG440 reduced pain scores in patients with joint discomfort, as measured by VAS (visual analog scale) methodology. As demonstrated in an ex vivo clinical study, these effects on pain relief may be due to reduced inflammatory cytokine production including lower prostaglandin E2 formation. Finally, strong data exist to suggest that NG440 is a safe formula for human consumption. Animal toxicity data revealed no adverse effects of NG440 at dosages < or =250 mg.kg-1.day-1 for 21 days. Furthermore, human trial data suggest that NG440 does not negatively impact cardiovascular and gastrointestinal markers normally affected by selective COX-2 enzyme inhibitors, including platelet function, blood pressure, blood cell count, or fecal calprotectin, a measure of gastrointestinal injury. In conclusion, NG440 may serve as a safe and efficacious alternative in some areas where specific COX-2 inhibitors have been traditionally used. 相似文献
25.
Substitution rates of organelle and nuclear genes in sharks: implicating metabolic rate (again) 总被引:7,自引:4,他引:3
Rates of nucleotide substitution for nuclear genes are thought to be
governed primarily by the number of germ line replication events (the
so-called "generation time" hypothesis). In contrast, rates of
mitochondrial DNA evolution appear to be set primarily by DNA damage
pathways of mutation mediated by mutagenic by-products of oxidative
phosphorylation (the so-called "metabolic-rate" hypothesis). Comparison of
synonymous substitution rates estimated for the mitochondrial cytochrome b
gene and nuclear-encoded dlx, hsp70, and RAG-1 genes in mammals and sharks
shows that rates of molecular evolution for sharks are approximately an
order of magnitude slower than those for mammals for both nuclear and
mitochondrial genes. In addition, there is significant positive covariation
of substitution rate for mitochondrial and nuclear genes within sharks.
These results, interpreted in light of the pervasiveness of DNA damage by
mutagenic by-products of oxygen metabolism to both nuclear and
mitochondrial genes and coupled with increasing evidence for cross-genome
activity of DNA repair enzymes, suggest that molecular clocks for
mitochondrial and nuclear genes may be set primarily by common mutational
mechanisms.
相似文献
26.
Slit is the midline repellent for the robo receptor in Drosophila 总被引:22,自引:0,他引:22
Previous studies suggested that Roundabout (Robo) is a repulsive guidance receptor on growth cones that binds to an unknown midline ligand. Here we present genetic evidence that Slit is the midline Robo ligand; a companion paper presents biochemical evidence that Slit binds Robo. Slit is a large extracellular matrix protein expressed by midline glia. In slit mutants, growth cones enter the midline but never leave it; they abnormally continue to express high levels of Robo while at the midline. slit and robo display dosage-sensitive genetic interactions, indicating that they function in the same pathway. slit is also required for migration of muscle precursors away from the midline. Slit appears to function as a short-range repellent controlling axon crossing of the midline and as a long-range chemorepellent controlling mesoderm migration away from the midline. 相似文献
27.
28.
Although immune responses following soft-tissue trauma-hemorrhage are markedly different in young (6-8 weeks) and aged (18-20 months) mice, it remains unknown if there are any differences in immune responses in middle-aged and young mice following bone fracture, soft-tissue trauma-hemorrhage (Fx-TH). To study this, young (6-8 weeks) and middle-aged (approximately 12 months) C3H/HeN male mice were subjected to sham operation or Fx-TH followed by resuscitation with Ringer's lactate. The mice were sacrificed 2 h thereafter and splenocytes, bone marrow cells (BM) and Kupffer cells (KC) were harvested, purified and stimulated with ConA (for splenocytes) or LPS (for BM and KC) in vitro. Splenocyte release of Th1 (IL-2 and IFN-gamma) cytokines was decreased and Th2 (IL-4 and IL-10) cytokine release was increased following Fx-TH in both young and middle-aged mice. However, the decrease in IL-2 and increase in IL-10 were significantly more in middle-aged mice compared to young mice (p < 0.05). Furthermore, splenocyte proliferation was decreased more in middle-aged mice compared to young mice following Fx-TH (p < 0.05). Additionally, TNF-alpha production was more in BM from middle-aged compared to BM from young mice after Fx-TH (p < 0.05). The production of IL-6 and IL-10 was also significantly higher in KC from middle-aged mice compared to young ones following Fx-TH. These results suggest that at middle age, the immune responses to Fx-TH are significantly different from those observed in young mice in different compartments of the body. Although the mechanism of the difference in various compartments in middle-aged vs. young mice following Fx-TH remains unknown, the decreased IL-2 production along with other altered T cell and macrophage functions may contribute to an increased susceptibility to sepsis in middle-aged vs. young individuals. 相似文献
29.
MacRitchie AN Albertine KH Sun J Lei PS Jensen SC Freestone AA Clair PM Dahl MJ Godfrey EA Carlton DP Bland RD 《American journal of physiology. Lung cellular and molecular physiology》2001,281(4):L1011-L1020
Nitric oxide (NO), produced in lung vascular endothelium and airway epithelium, has an important role in regulating smooth muscle cell growth and tone. Chronic lung disease, a frequent complication of premature birth, is characterized by excess abundance, tone, and reactivity of smooth muscle in the pulmonary circulation and conducting airways, leading to increased lung vascular and airway resistance. Whether these structural and functional changes are associated with diminished pulmonary expression of endothelial nitric oxide synthase (eNOS) protein is unknown. Both quantitative immunoblot analysis and semiquantitative immunohistochemistry showed that there was less eNOS protein in the endothelium of small intrapulmonary arteries and epithelium of small airways of preterm lambs that were mechanically ventilated for 3 wk compared with control lambs born at term. No significant differences were detected for other proteins (inducible NOS, alpha-smooth muscle actin, and pancytokeratin). Lung vascular and respiratory tract resistances were greater in the chronically ventilated preterm lambs compared with control term lambs. These results support the notion that decreased eNOS in the pulmonary circulation and respiratory tract of preterm lambs may contribute to the pathophysiology of chronic lung disease. 相似文献
30.
Decreased 5alpha-dihydrotestosterone catabolism suppresses T lymphocyte functions in males after trauma-hemorrhage 总被引:1,自引:0,他引:1
Zheng R Samy TS Schneider CP Rue LW Bland KI Chaudry IH 《American journal of physiology. Cell physiology》2002,282(6):C1332-C1338
Trauma-hemorrhage producesprofound immunosuppression in males but not in proestrus females.Prior castration or flutamide treatment of males followingtrauma-hemorrhage prevents immunosuppression, implicating5-dihydrotestosterone for the immunosuppressive effects. 5-Dihydrotestosterone, a high-affinity androgen receptor-binding steroid, is synthesized in tissues as needed and seldom accumulates. The presence of steroidogenic enzymes in T lymphocytes suggests bothsynthesis and catabolism of 5-dihydrotestosterone. We hypothesized, therefore, that the basis for high 5-dihydrotestosterone activity inT lymphocytes of males following trauma-hemorrhage is due to decreasedcatabolism. Accordingly, catabolism of 5-dihydrotestosterone wasassessed in splenic T lymphocytes by examining the activity andexpression of enzymes involved. Analysis showed increased synthesis anddecreased catabolism of 5-dihydrotestosterone in intact male Tlymphocytes following trauma-hemorrhage. In contrast, reduced5-reductase activity and increased expression of17-hydroxysteroid dehydrogenase oxidative isomers suggestinactivation of 5-dihydrotestosterone in precastrated males. Thusour study suggests increased synthesis and decreased catabolism of5-dihydrotestosterone as a reason for loss of T lymphocyte functionsin intact males following trauma-hemorrhage, as evidenced by decreasedrelease of interleukin-2 and -6. 相似文献