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The unfolded protein response signaling and retinal müller cell metabolism

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Neural Regeneration Research 2018年第11期13卷 1861-1870页

作者： Kristen Kelly joshua j.Wang Sarah X.Zhang Department of Ophthalmology and Neuroscience Program Ross Eye InstituteUniversity at BuffaloState University of New York SUNY Eye Institute State University of New YorkBuffaloNYUSA

The retina is one of the most energy demanding tissues in the body. Like most neurons in the central nervous system, retinal neurons consume high amounts of adenosine-5′-triphosphate（ATP） to generate visual signal and transmit the information to the brain. Disruptions in retinal metabolism can cause neuronal dysfunction and degeneration resulting in severe visual impairment and even blindness. The homeostasis of retinal metabolism is tightly controlled by multiple signaling pathways, such as the unfolded protein response（UPR）, and the close interactions between retinal neurons and other retinal cell types including vascular cells and müller glia. The UPR is a highly conserved adaptive cellular response and can be triggered by many physiological stressors and pathophysiological conditions. Activation of the UPR leads to changes in glycolytic rate, ATP production, de novo serine synthesis, and the hexosamine biosynthetic pathway, which are considered critical components of müller glia metabolism and provide metabolic support to surrounding neurons. When these pathways are disrupted, neurodegeneration occurs rapidly. In this review, we summarize recent advance in studies of the UPR in müller glia and highlight the potential role of the UPR in retinal degeneration through regulation of müller glia metabolism.

关键词： unfolded protein response retina müller glia metabolism neurodegeneration X-box binding protein 1 glycolysis glucose transporter

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大学化学第5版

大学化学第5版

major Limb Amputations: Etiological and Clinical Profile in a Hospital in Sub-Saharan Africa

1967年

作者： m j.Sienko R A.Plane 沈克恒译

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Open journal of Orthopedics 2021年第2期11卷 40-46页

作者： S. Diao A. N. Kassé j. D. Diouf j. C. Sané B. Thiam m. B. Diallo m. H. Sy Department of Orthopedics and Trauma Surgery General Hospital Idrissa Pouye Dakar Sénégal

Introduction: During the 19th and 20th centuries, the Wars were the cause of many amputations among military and civilians. Despite the absence of armed conflict in our country, we notice a high frequency of major amputations in our activity. Objective: The aim of this work was to study the causes of major amputations observed in our practice in order to develop preventive measures. Materials and Method: This was a descriptive retrospective study over a 6-year period, from January 1, 2008 to December 31, 2014. The following parameters were studied: epidemiological aspects (age according to WHO age groups and gender of patients), type of amputation, level of amputation and causes. Results: Two hundred and fifty-two patients were included. The distribution of amputations by cause and age group showed two distinct entities: The forms of the young subject where there was a predominance of tumour and traumatic causes;and the forms of the elderly person caused by vascular infections and conditions. Infections were the main cause of amputation in both sexes. Conclusion: The causes of major limb amputations vary according to age and limb: tumor and trauma in young people and for the upper limb, infectious and vascular in the elderly and for the lower limb.

关键词： Diabetes Disarticulation Infections Limb major Amputation Tumors

Stable gravastars： Guilfoyle＇s electrically charged solutions

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Chinese Physics C 2018年第11期42卷 120-130页

作者： Ayan Banerjee j.R. Villanueva Phongpichit Channuie Kimet jusufi Department of mathematics Jadavpur University Kolkata-700032 India Instituto de Fisica y Astronomia Facultad de Ciencias Universidad de Valparaiso Gran Bretana 1111 Valparaiso Chile School of Science Walailak University Nakhon Si Thammarat 80160 Thailand Physics Department State University of Tetovo Ilinden Street nn 1200 Macedonia

Compelling alternatives to black holes, namely, gravitational vacuum stars （gravastars）, which are multilayered compact objects, have been proposed to avoid a number of theoretical problems associated with event horizons and singularities. In this work, we construct a spherically symmetric thin-shell charged gravastar model where the vacuum phase transition between the de Sitter interior and the external Reissner-Nordstrom spacetime （RN） are matched at a junction surface, by using the cut-and-paste procedure. Gravastar solutions are found among the Guilfoyle exact solutions where the gravitational potential We and the electric potential field Ф obey a particular relation in a simple form a（b-εФ）^2＋b1, where a, b and bl are arbitrary constants. The simplest ansatz of Guilfoyle＇s solution is implemented by the following assumption： that the total energy density 8πρm＋Q^2/r^4 is constant, where Q（r） is the electric charge up to a certain radius r. We show that, for certain ranges of the parameters, we can avoid the horizon formation, which allows us to study the linearized spherically symmetric radial perturbations around static equilibrium solutions. To lend our solution theoretical support, we also analyze the physical and geometrical properties of gravastar configurations.

关键词： gravastar Guilfoyle exact solutions stability analysis

Evaluation of Daily Gridded meteorological Datasets over the Niger Delta Region of Nigeria and Implication to Water Resources management

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Atmospheric and Climate Sciences 2020年第1期10卷 21-39页

作者： Ibrahim Hassan Robert m. Kalin Christopher j. White jamiu A. Aladejana Department of Civil and Environmental Engineering University of Strathclyde Glasgow UK Department of Civil Engineering Abubakar Tafawa Balewa University Bauchi Nigeria Department of Geology University of Ibadan Ibadan Nigeria

Hydro-climatological study is difficult in most of the developing countries due to the paucity of monitoring stations. Gridded climatological data provides an opportunity to extrapolate climate to areas without monitoring stations based on their ability to replicate the Spatio-temporal distribution and variability of observed datasets. Simple correlation and error analyses are not enough to predict the variability and distribution of precipitation and temperature. In this study, the coefficient of correlation (R2), Root mean square error (RmSE), mean bias error (mBE) and mean wet and dry spell lengths were used to evaluate the performance of three widely used daily gridded precipitation, maximum and minimum temperature datasets from the Climatic Research Unit (CRU), Princeton University Global meteorological Forcing (PGF) and Climate Forecast System Reanalysis (CFSR) datasets available over the Niger Delta part of Nigeria. The Standardised Precipitation Index was used to assess the confidence of using gridded precipitation products on water resource management. Results of correlation, error, and spell length analysis revealed that the CRU and PGF datasets performed much better than the CFSR datasets. SPI values also indicate a good association between station and CRU precipitation products. The CFSR datasets in comparison with the other data products in many years overestimated and underestimated the SPI. This indicates weak accuracy in predictability, hence not reliable for water resource management in the study area. However, CRU data products were found to perform much better in most of the statistical assessments conducted. This makes the methods used in this study to be useful for the assessment of various gridded datasets in various hydrological and climatic applications.

关键词： Climate Research Unit (CRU) Princeton University Global meteorological Forcing Dataset (PGF) Climate Forecast System Reanalysis (CFSR) Standardised Precipitation Index (SPI)

Dispersal of the Zhujiang River(Pearl River) derived sediment in the Holocene

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Acta Oceanologica Sinica 2014年第8期33卷 1-9页

作者： GE Qian LIU j.P. XUE Zuo CHU Fengyou Key Laboratory of Submarine Geosciences State Oceanic AdministrationSecond Institute of OceanographyState Oceanic Administration Department of marine Earth and Atmospheric SciencesNorth Carolina State UniversityRaleighNC 27695USA

High-resolution Chirp profiling and coring reveals an elongated （ca. 400 km） Holocene Zhujiang River （Pearl River）-derived mud area （maximum thickness 〉 20 m） extending from the Zhujiang River Delta, southwest-ward off the Guangdong coast, to the Leizhou Peninsula. Two depo-centers, one proximal and one distal, are identified. On the continental shelf off the west Guangdong Province, the mud is deposited in water depth shallower than 50 m; while to the southeast of the Zhujiang River Estuary, the mud area can extend to the -120 m isobath. A combined analysis with the stratigraphic sequences of other muddy deposits in the West-ern Pacific marginal seas （mainly Changjiang （Yangtze） and Huanghe （Yellow） Rivers derived） indicates that the initiation of the Zhujiang River muddy deposit can be further divided into two stages： Stage 1 is before the mid-Holocene sea-level highstand （ca. 7.0 cal. ka BP）, the proximal mud was mostly deposited after 9.0 cal. ka BP, when the sea-level rose slowly after the meltwater Pulse -1C; Stage 2, after the mid-Holocene sea-level highstand, clinoform developed on the continental shelf off the west Guangdong Province, extending ca. 400 km from the Zhujiang River Estuary. The proximal clinoform thins offshore, from ca. 10 m thickness around 5-10 m water depth to less than 1-2 m around 20-30 m water depth. In addition, we also find a de-veloped distal clinoform in the east of the Leizhou Peninsula.

关键词： South China Sea Zhujiang River mud clinoform

HBsAg无症状携带者乙型肝炎病毒核心基因启动子突变的研究

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中国预防医学杂志 2011年第6期12卷 464-467页

作者：王学燕李国坚董柏青杨进业陈钦艳方孔雄方钟燎 Tim j harrison 广西壮族自治区疾病预防控制中心广西南宁530028 广西壮族自治区卫生厅隆安县疾病预防控制中心英国伦敦大学学院

目的了解HBsAg无症状携带者乙型肝炎病毒(HBV)核心基因启动子双突变(nt1762 A→T,nt1764 G→A)发生情况及其与基因型、病毒量和HBeAg的关系。方法 HBsAg无症状携带者从隆安研究队列中选择,用套式聚合酶链反应(nested PCR)对研究对象血清... 详细信息

目的了解HBsAg无症状携带者乙型肝炎病毒(HBV)核心基因启动子双突变(nt1762 A→T,nt1764 G→A)发生情况及其与基因型、病毒量和HBeAg的关系。方法 HBsAg无症状携带者从隆安研究队列中选择,用套式聚合酶链反应(nested PCR)对研究对象血清HBV核心基因启动子、S基因扩增、序列分析及基因分型,用HBV引物和双标记的Taqman探针扩增和定量病毒DNA。结果观察开始时核心基因启动子为野毒株的109例观察对象,3年后双突变平均年发生率为2.8%;观察开始时已发生nt1762或nt1764点突变的59例对象,3年后另一个位点也发生突变的平均年发生率为6.8%,两率差异有统计学意义(χ2=5.109 0,P0.05)。5例双突变发生后HBeAg仍然阳性者病毒量有下降趋势,而另5例突变发生后HBeAg阴性者其病毒量有升有降。结论 HBV核心基因启动子双突变年发生率较高,这两个位点中的任何一个发生突变是双突变的过渡形式,双突变与基因型无关,nt1764 G→A突变与HBeAg阴性有关。

关键词：乙型肝炎病毒核心基因启动子突变

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大学化学

大学化学

Visual ＂playback＂ of colorful signals in the field supports sensory drive for signal detectability

1978年

作者： m j.Sienko RA.Plane 沈克恒译

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Current Zoology 2018年第4期64卷 493-498页

作者： Alex R. GUNDERSON Leo j. FLEISHmAN manuel LEAL Department of Integrative Biology University of California Berkeley CA 94720 USA Department of Biology Union College Schenectady NY 12308 USA Division of Biological Sciences University of Missouri 105 Tucker Hall Columbia MO 65211 USA

Colorful visual signals are important systems for investigating the effects of signaling environ ments and receiver physiology on signal evolution as predicted by the sensory drive hypothesis. Support for the sensory drive hypothesis on color signal evolution is mostly based on document ing correlations between the properties of signals and habitat conditions under which the signals are given （i.e., a correlational approach） and less commonly on the use of mathematical models that integrate representations of visual environments, signal properties, and sensory systems （i.e., a functional approach）. Here, we used an experimental approach in the field to evaluate signal efficacy of colorful lizard throat fans called dewlaps that show geographic variation in the lizard Anolis cristatellus. We used a remote controlled apparatus to display ＂fake dewlaps＂ to wild lizards to test for adaptive divergence in dewlap brightness （i.e., perceived intensity） among populations in situ. We found evidence of local adaptation in dewlap brightness consistent with the sensory drive hypothesis. Specifically, dewlaps that had the brightness characteristics of local lizards were more likely to be detected than those with the brightness characteristics of nonlocal lizards. Our findings indicate that simplified mathematical representations of visual environments may allow robust estimates of relative detectability or conspicuousness in natural habitats. We have shown the feasibility of evaluating color signal efficacy experimentally under natural conditions and dem onstrate the potential advantages of presenting isolated components of signals to an intended re ceiver to measure their contribution to signal function.

关键词： Anolis color signal sensory drive signal evolution