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11.
Capillaria hepatica parasitism 总被引:1,自引:0,他引:1
Capillaria hepatica is rarely encountered in humans, with fewer than 30 documented cases. The clinico-pathological features
of capillaria hepatica infection, diagnosed on liver biopsy of a 6-year-old child are discussed. Pathologically, it is characterised
by prominent granulomatous lesions in the liver surrounding the eggs, which on cursory examination may be confused withSchistosoma mansoni. 相似文献
12.
Nirmala Chandrasekar Sanjeeva Mohanam S Sajani Lakka Dzung H Dinh William C Olivero Meena Gujrati Jasti S Rao 《Clinical cancer research》2003,9(6):2342-2349
PURPOSE: Tumor vasculature provides the infrastructure by which malignant tissue can be nourished; therefore, targeting angiogenesis may be an effective means of treating cancer. We showed previously that SNB19 glioblastoma cells modulate bovine retinal endothelial cells in cocultures to form capillary-like network structures, that matrix metalloproteinase-9 (MMP-9) expression is critical for endothelial morphogenesis, and that MMP-9 expression in glioblastoma cells is regulated by extracellular signal-regulated kinase-1 (ERK-1). In the present study, we investigated whether interfering with the activation of this mitogen-activated protein (MAP) kinase would repress MMP-9 synthesis and inhibit capillary formation. EXPERIMENTAL DESIGN: Cocultures of bovine retinal endothelial and SNB19 cells were analyzed for MMP-9 secretion, and phospho- and total ERK levels. These cocultures were treated with PD98059, a specific inhibitor of MAP/ERK kinase 1, or transfected with dominant-negative ERK-1 mutant containing expression vector. Alterations in capillary-like structure formation, and actin cytoskeleton and secretion of vascular endothelial growth factor (VEGF), MMP-9, and tissue inhibitor of metalloproteinase-1 were determined by immunofluorescence, gelatin zymography, and Western blotting. RESULTS: We found that inhibition of the ERK-1/2 pathway with PD98059 abrogated glial cell-mediated capillary formation by the endothelial cells and reduced the levels of MMP-9 in the coculture. Strikingly, the abrogation of MAP kinase signaling by a dominant-negative ERK-1 mutant inhibited glial-induced capillary network formation by reducing VEGF levels and MMP-9 activity and increasing the levels of tissue inhibitor of metalloproteinase-1. Inhibition of ERK activity also disrupted the formation of the actin cytoskeleton, a prerequisite for endothelial cell migration. CONCLUSION: The mechanism underlying activation of ERK is involved in reorganization of the actin cytoskeleton, and induction of VEGF and MMP-9, thereby stimulating endothelial cell morphogenesis. These studies clearly provide experimental evidence that ERK inhibition diminishes glial-induced endothelial-cell morphogenesis; therefore, interfering with ERK signaling may be a viable approach to target angiogenesis. 相似文献
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Thirunavukarasu Kajana Arumugam Pirashanthan Dhayalan Velauthapillai Akila Yuvapragasam Shivatharsiny Yohi Punniamoorthy Ravirajan Meena Senthilnanthanan 《RSC advances》2022,12(28):18041
Electrochemical energy storage has attracted much attention due to the common recognition of sustainable energy development. Transition metal sulfides and post-transition metal sulfides have been intensively been focused on due to their potential as electrode materials for energy storage applications in different types of capacitors such as supercapacitors and pseudocapacitors, which have high power density and long cycle life. Herein, the physicochemical properties of transition and post-transition metal sulfides, their typical synthesis, structural characterization, and electrochemical energy storage applications are reviewed. Various perspectives on the design and fabrication of transition and post-transition metal sulfides-based electrode materials having capacitive applications are discussed. This review further discusses various strategies to develop transition and/or post-transition metal sulfide heterostructured electrode-based self-powered photocapacitors with high energy storage efficiencies.Electrochemical energy storage has attracted much attention due to the common recognition of sustainable energy development. 相似文献
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Germline mutations of the Apc tumor suppressor gene result in increased risk for gastrointestinal carcinogenesis. The Apc1638N [+/-] mouse exhibits accelerated gastrointestinal carcinogenesis that is modifiable by select pharmacological and dietary agents. Experiments in the present study were conducted on a subculturable epithelial 1638NCOL cell line established from histologically normal colon of Apc1638N [+/-] mouse to examine the effects of selected chemopreventive agents that differ in their mechanism of action. Extent of growth arrest, number of cell population doublings, cell cycle progression and aneuploid G0/G1: S + G2/M ratio represented the quantitative endpoints for the susceptibility and efficacy of chemopreventive agents. Treatment of exponentially growing 1638NCOL cells with maximum cytostatic dose of 9cisRA, DFMO or SUL (100 microM) produced a 60-70% growth arrest, that with TAM and AMF (10 microM) produced a 20-40% growth arrest, while that with OLT (100 microM) produced a 25% growth arrest. This response was associated with corresponding decrease in the number of cell population doubling. 9cisRA, SUL or AMF increased the aneuploid G0/G1: S + G2/M ratio by inducing G1 checkpoint arrest, while DFMO, TAM and OLT decreased the ratio by inducing G2 checkpoint arrest. Thus, cell cycle phase-dependent susceptibility of the Apc [+/-] 1638NCOL cell line to mechanistically distinct chemopreventive agents validates a novel colon epithelial cell culture model for mechanistic, preventive or therapeutic studies on Apc regulated colon carcinogenesis. 相似文献
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Community mobility supports occupational participation among older adults and promotes active ageing. This study aimed to explore community mobility of older adults within an urban Indian context in view of the limited available literature in this area. A cross-sectional survey was conducted on a convenience sample of 75 older adults residing in Chennai city using a questionnaire and a non-retrospective, open format, two-day time diary. Participants engaged in community mobility and activities outside home for 10 % of time over two days. Activities and roles related to religious and spiritual activities and expression, social participation, leisure and informal personal education participation occupied most time and were engaged in most frequently. Walking was the most frequently used mode of transportation and participants reported numerous road-related hazards (lack of proper pavements, disobedience of traffic rules, difficulty crossing roads, crowded roads, and poor condition of roads). Participants used public transport less often. Public transport-related barriers (difficulty boarding and alighting buses/trains due to high steps/insufficient time, inadequate seat reservation for older adults, overcrowding and increased expense on auto rickshaws/taxis) were also expressed as concerns. Participants linked their ability to use public transport with independence and assigned relatively less value to driving. The findings emphasize the significance of community mobility to promote participation in older adults and recommend age-friendly environments in Indian cities. 相似文献
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Shelly Choo Henry Perry Afua A. J. Hesse Francis Abantanga Elias Sory Hayley Osen Charles Fleischer‐Djoleto Rachel Moresky Colin W. McCord Meena Cherian Fizan Abdullah 《Tropical medicine & international health : TM & IH》2010,15(9):1109-1115
Objectives To survey infrastructure characteristics, personnel, equipment and procedures of surgical, obstetric and anaesthesia care in 17 hospitals in Ghana. Methods The assessment was completed by WHO country offices using the World Health Organization Tool for Situational Analysis to Assess Emergency and Essential Surgical Care, which surveyed infrastructure, human resources, types of surgical interventions and equipment in each facility. Results Overall, hospitals were well equipped with general patient care and surgical supplies. The majority of hospitals had a basic laboratory (100%), running water (94%) and electricity (82%). More than 75% had the basic supplies needed for general patient care and basic intra‐operative care, including sterilization. Almost all hospitals were able to perform major surgical procedures such as caesarean sections (88%), herniorrhaphy (100%) and appendectomy (94%), but formal training of providers was limited: a few hospitals had a fully qualified surgeon (29%) or obstetrician (36%) available. Conclusions The greatest barrier to improving surgical care at district hospitals in Ghana is the shortage of adequately trained medical personnel for emergency and essential surgical procedures. Important future steps include strengthening their number and qualifications. 相似文献