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1.
1.  At 28°C conversion efficiency of total nitrogen (TN) was inversely related to size.
2.  In the pre-adult stage protein nitrogen (PN) conversion efficiency was high whereas in the Post-adult stage non-protein nitrogen (NPN) conversion efficiency was high.
3.  Lower temperature (20°C) was not congenial for PN conversion.
4.  Higher temperature favoured PN conversion for smaller fish but NPN for larger fish.
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Background

Malawi ratified a compulsory birth and death registration system in 2009. Until it captures complete coverage of vital events, Malawi relies on other data sources to calculate mortality estimates. We tested a community-based method to estimate annual under-five mortality rates (U5MR) through the Real-Time Monitoring of Under-Five Mortality (RMM) project in Malawi. We implemented RMM in two phases, and conducted an independent evaluation of phase one after 21 months of implementation. We present results of the phase two validation that covers the full project time span, and compare the results to those of the phase one validation.

Methods and Findings

We assessed the completeness of the counts of births and deaths and the accuracy of disaggregated U5MR from the community-based method against a retrospective full pregnancy history for rolling twelve-month periods after the independent evaluation. We used full pregnancy histories collected through household interviews carried out between November 2013 and January 2014 as the validation data source. Health Surveillance Agents (HSAs) across the 160 catchment areas submitted routine reports on pregnancies, births, and deaths consistently. However, for the 15-month implementation period post-evaluation, average completeness of birth event reporting was 76%, whereas average completeness of death event reporting was 67% relative to that expected from a comparable pregnancy history. HSAs underestimated the U5MR by an average of 21% relative to that estimated from a comparable pregnancy history.

Conclusions

On a medium scale, the community-based RMM method in Malawi produced substantial underestimates of annualized U5MR relative to those obtained from a full pregnancy history, despite the additional incentives and quality-control activities. We were not able to achieve an optimum level of incentive and support to make the system work while ensuring sustainability. Lessons learned from the implementation of RMM can inform programs supporting community-based interventions through HSAs in Malawi.  相似文献   
4.

Background

Diarrhea is one of the leading causes of childhood morbidity and mortality. Hospitalization for diarrhea can pose a significant burden to health systems and households. The objective of this study was to estimate the economic burden attributable to hospitalization for diarrhea among children less than five years old in Rwanda. These data can be used by decision-makers to assess the impact of interventions that reduce diarrhea morbidity, including rotavirus vaccine introduction.

Methods

This was a prospective costing study where medical records and hospital bills for children admitted with diarrhea at three hospitals were collected to estimate resource use and costs. Hospital length of stay was calculated from medical records. Costs incurred during the hospitalization were abstracted from the hospital bills. Interviews with the child’s caregivers provided data to estimate household costs which included transport costs and lost income. The portion of medical costs borne by insurance and household were reported separately. Annual economic burden before and after rotavirus vaccine introduction was estimated by multiplying the reported number of diarrhea hospitalizations in public health centers and district hospitals by the estimated economic burden per hospitalization. All costs are presented in 2014 US$.

Results

Costs for 203 children were analyzed. Approximately 93% of the children had health insurance coverage. Average hospital length of stay was 5.3 ± 3.9 days. Average medical costs for each child for the illness resulting in a hospitalization were $44.22 ± $23.74 and the total economic burden was $101, of which 65% was borne by the household. For households in the lowest income quintile, the household costs were 110% of their monthly income. The annual economic burden to Rwanda attributable to diarrhea hospitalizations ranged from $1.3 million to $1.7 million before rotavirus vaccine introduction.

Conclusion

Households often bear the largest share of the economic burden attributable to diarrhea hospitalization and the burden can be substantial, especially for households in the lowest income quintile.  相似文献   
5.
The coastal forests of Kenya are conservation priorities hosting high levels of biodiversity. Monitoring of biodiversity in these forests is therefore necessary to understand and reverse negative trends in good time. Using the Important Bird Area (IBA) monitoring framework, a participatory approach, state (habitat condition), pressure (threats) and response (conservation action) indicators of twelve coastal Kenya forest IBAs were assessed from 2004 to 2011. Trends for these indicators were assessed at six sites for which sufficient data existed: Arabuko‐Sokoke, Dakatcha Woodlands, Gede Ruins, Lower Tana River, Shimba Hills and Taita Hills, and baselines were described for remaining six. Changes were always small, but state deteriorated in Gede, Lower Tana and Shimba Hills, remained the same (unfavourable) in Arabuko‐Sokoke and Dakatcha, and improved in Taita Hills. Pressure reduced in Arabuko‐Sokoke, Dakatcha and Taita Hills, deteriorated in Lower Tana and Shimba Hills and remained the same (medium) in Gede. Response improved in Dakatcha, remained the same (medium) in Shimba Hills, and deteriorated in the rest. As there was an apparent overall deterioration in the forests assessed, improved management of the protected sites and increased conservation action through community engagement around protected areas and within the nonprotected IBAs are recommended.  相似文献   
6.
Mitochondrial damage is a well known cause of mitochondria-related diseases. A major mechanism underlying the development of mitochondria-related diseases is thought to be an increase in intracellular oxidative stress produced by impairment of the mitochondrial electron transport chain (ETC). However, clear evidence of intracellular free radical generation has not been clearly provided for mitochondrial DNA (mtDNA)-damaged cells. In this study, using the novel fluorescence dye, 2-[6-(4'-hydroxy)phenoxy-3H-xanthen-3-on-9-yl]benzoic acid (HPF), which was designed to detect hydroxyl radicals (*OH), intracellular free radical formation was examined in 143B cells (parental cells), 143B-rho(0) cells (mtDNA-lacking cells), 87 wt (cybrid), and cybrids of 4977-bp mtDNA deletion (common deletion) cells containing the deletion with 0%, 5%, 50% and >99% frequency (HeLacot, BH5, BH50 and BH3.12, respectively), using a laser confocal microscope detection method. ETC inhibitors (rotenone, 3-nitropropionic acid, thenoyltrifluoroacetone, antimycin A and sodium cyanide) were also tested to determine whether inhibitor treatment increased intracellular reactive oxygen species (ROS) generation. A significant increase in ROS for 143B-rho(0) cells was observed compared with 143B cells. However, for the 87 wt cybrid, no increase was observed. An increase was also observed in the mtDNA-deleted cells BH50 and BH3.12. The ETC inhibitors increased intracellular ROS in both 143B and 143B-rho(0) cells. Furthermore, in every fluorescence image, the fluorescence dye appeared localized around the nuclei. To clarify the localization, we double-stained cells with the dye and MitoTracker Red. The resulting fluorescence was consistently located in mitochondria. Furthermore, manganese superoxide dismutase (MnSOD) cDNA-transfected cells had decreased ROS. These results suggest that more ROS are generated from mitochondria in ETC-inhibited and mtDNA-damaged cells, which have impaired ETC.  相似文献   
7.
Recent research communications indicate that the adult human brain contains undifferentiated, multipotent precursors or neural stem cells. It is not known, however, whether these cells can develop into fully functional neurons. We cultured cells from the adult human ventricular wall as neurospheres and passed them at the individual cell level to secondary neurospheres. Following dissociation and plating, the cells developed the antigen profile of the three main cell types in the brain (GFAP, astrocytes; O2, oligodendrocytes; and beta-III-tubulin/NeuN, neurons). More importantly, the cells developed the electrophysiological profiles of neurons and glia. Over a period of 3 weeks, neuron-like cells went through the same phases as neurons do during development in vivo, including up-regulation of inward Na+ -currents, drop in input resistance, shortening of the action potential, and hyperpolarization of the cell membrane. The cells developed overshooting action potentials with a mature configuration. Recordings in voltage-clamp mode displayed both the fast inactivating TTX-sensitive sodium current (INa) underlying the rising phase of the action potential and the two potassium currents terminating the action potential in mature neurons (IA and IK, sensitive to 4-AP and TEA, respectively). We have thus demonstrated that the human ventricular wall contains multipotent cells that can differentiate into functionally mature neurons.  相似文献   
8.
To develop an inducible and progressive model of mammary gland tumorigenesis, transgenic mice were generated with a mouse mammary tumor virus-long terminal repeat-driven, conditional, fibroblast growth factor (FGF)-independent FGF receptor (FGFR)1 (iFGFR1) that can be induced to dimerize with the drug AP20187. Treatment of transgenic mice with AP20187 resulted in iFGFR1 tyrosine phosphorylation, increased proliferation, activation of mitogen-activated protein kinase and Akt, and lateral budding. Lateral buds appeared as early as 3 d after AP20187 treatment and initially consisted of bilayered epithelial cells and displayed apical and basolateral polarity appeared after 13 d of AP20187 treatment. Invasive lesions characterized by multicell-layered lateral buds, decreased myoepithelium, increased vascular branching, and loss of cell polarity were observed after 2-4 wk of treatment. These data indicate that acute iFGFR1 signaling results in increased lateral budding of the mammary ductal epithelium, and that sustained activation induces alveolar hyperplasia and invasive lesions.  相似文献   
9.
Hepatitis B virus core antigen (HBcAg) plays a critical role in terminating acute Hepatitis B virus infection and may be used as a potential vaccine candidate. The cell surface major histocompatibility complex (MHC) class 1 molecules are thought to be involved in the presentation of HBcAg. Surface MHC class 1 HLA A2 heavy chain (HC) and trimeric molecules were characterized on transfected Hela cells used as antigen presenting cells (APC) for the presentation of HBcAg. The results show that antibodies against HC HLA A2 and trimeric HLA-A2 molecules resulted in increased activation of HBcAg 18-27 minimal peptide specific cytotoxic T lymphocytes (CTLs), while the addition of exogenous beta2-microglobulin decreased the activation of HBcAg specific CTLs. Further, specific CD8+ T cells were activated only when Hela cells as APCs were primed with HBcAg (peptide, soluble or embedded on virosomes) at pH 6.5.  相似文献   
10.
An extension of our previously reported series of macrocyclic ortho-aminobenzamide Hsp90 inhibitors is reported. Addition of a second methyl group to the tether provided analogs that show increased potency in binding as well as cell-proliferation assays and, more importantly, are stable toward microsomes. We wish to disclose the discovery of a macrocycle which showed impressive biomarker activity 24-h post dosing and which demonstrated prolonged exposure in tumors. When studied in a lung cancer xenograft model, the compound demonstrated significant tumor size reduction.  相似文献   
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