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261.
Mosquitoes are important vectors that transmit pathogens to human and other vertebrates. Each mosquito species has specific ecological requirements and bionomic traits that impact human exposure to mosquito bites, and hence disease transmission and vector control. A study of human biting mosquitoes and their bionomic characteristics was conducted in West Sumba and Southwest Sumba Districts, Nusa Tenggara Timur Province, Indonesia from May 2015 to April 2018. Biweekly human landing catches (HLC) of night biting mosquitoes both indoors and outdoors caught a total of 73,507 mosquito specimens (59.7% non-Anopheles, 40.3% Anopheles). A minimum of 22 Culicinae species belonging to four genera (Aedes, Armigeres, Culex, Mansonia), and 13 Anophelinae species were identified. Culex quinquefasciatus was the dominant Culicinae species, Anopheles aconitus was the principal Anopheles species inland, while An. sundaicus was dominant closer to the coast. The overall human biting rate (HBR) was 10.548 bites per person per night (bpn) indoors and 10.551 bpn outdoors. Mosquitoes biting rates were slightly higher indoors for all genera with the exception of Anopheles, where biting rates were slightly higher outdoors. Diurnal and crepuscular Aedes and Armigeres demonstrated declining biting rates throughout the night while Culex and Anopheles biting rates peaked before midnight and then declined. Both anopheline and non-anopheline populations did not have a significant association with temperature (p = 0.3 and 0.88 respectively), or rainfall (p = 0.13 and 0.57 respectively). The point distribution of HBR and seasonal variables did not have a linear correlation. Data demonstrated similar mosquito–human interactions occurring outdoors and indoors and during early parts of the night implying both indoor and outdoor disease transmission potential in the area–pointing to the need for interventions in both spaces. Integrated vector analysis frameworks may enable better surveillance, monitoring and evaluation strategies for multiple diseases.  相似文献   
262.
Endothelial dysfunction is a hallmark of inflammation and is mediated by inflammatory factors that signal through G protein–coupled receptors including protease-activated receptor-1 (PAR1). PAR1, a receptor for thrombin, signals via the small GTPase RhoA and myosin light chain intermediates to facilitate endothelial barrier permeability. PAR1 also induces endothelial barrier disruption through a p38 mitogen-activated protein kinase–dependent pathway, which does not integrate into the RhoA/MLC pathway; however, the PAR1-p38 signaling pathways that promote endothelial dysfunction remain poorly defined. To identify effectors of this pathway, we performed a global phosphoproteome analysis of thrombin signaling regulated by p38 in human cultured endothelial cells using multiplexed quantitative mass spectrometry. We identified 5491 unique phosphopeptides and 2317 phosphoproteins, four distinct dynamic phosphoproteome profiles of thrombin-p38 signaling, and an enrichment of biological functions associated with endothelial dysfunction, including modulators of endothelial barrier disruption and a subset of kinases predicted to regulate p38-dependent thrombin signaling. Using available antibodies to detect identified phosphosites of key p38-regulated proteins, we discovered that inhibition of p38 activity and siRNA-targeted depletion of the p38α isoform increased basal phosphorylation of extracellular signal–regulated protein kinase 1/2, resulting in amplified thrombin-stimulated extracellular signal–regulated protein kinase 1/2 phosphorylation that was dependent on PAR1. We also discovered a role for p38 in the phosphorylation of α-catenin, a component of adherens junctions, suggesting that this phosphorylation may function as an important regulatory process. Taken together, these studies define a rich array of thrombin- and p38-regulated candidate proteins that may serve important roles in endothelial dysfunction.  相似文献   
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Abstract The c -type cytochrome and protein profiles were compared for a number of cultures of Paracoccus denitrificans obtained from a range of culture collections. The cultures fell into two groups corresponding to the two original isolates of this bacterial species. One group, which included NCIMB 8944, ATCC 13543, ATCC 17741, ATCC 19367, Pd 1222 and DSM 413, were similar or identical to LMD 22.21. The second group, including DSM 65 and LMG 4218, were similar or identical to LMD 52.44. These groupings were not compatible with the recorded history of culture deposition. Mass spectrometry and amino acid sequence comparisons showed that the cytochrome c -550 of the LMD 52.44 culture group differed by 16% from that of the LMD 22.21 group, and yet was only 1% different from the cytochrome c -550 of Thiosphaera pantotropha . These results suggest that consideration should be given to creation of a new species of Paracoccus pantotropha , which would include Thiosphaera pantotropha and Paracoccus denitrificans LMD 52.44.  相似文献   
265.
Abstract Cells of Pasteurella haemolytica A2 were harvested directly from the pleural fluid of sheep with pneumonic pasteurellosis and the protein composition of their envelopes was examined by SDS-PAGE. Several high molecular-weight proteins expressed in pleural fluid were absent when the same isolate was grown in nutrient broth, but were produced during culture in iron restricted media. When the cell wall envelopes were examined by immunoblotting with sera and lung washes of lambs recovering from pneumonic pasteurellosis, antibodies to the major outer membrane proteins, the iron-regulated proteins and one other 'in vivo'-expressed antigen were present. These results have implications for the formulation of effective vaccines against pasteurellosis in sheep.  相似文献   
266.
Eastern equine encephalitis virus (EEEV) is mosquito-borne virus that produces fatal encephalitis in humans. We recently conducted a first of its kind study to investigate EEEV clinical disease course following aerosol challenge in a cynomolgus macaque model utilizing the state-of-the-art telemetry to measure critical physiological parameters. Here, we report the results of a comprehensive pathology study of NHP tissues collected at euthanasia to gain insights into EEEV pathogenesis. Viral RNA and proteins as well as microscopic lesions were absent in the visceral organs. In contrast, viral RNA and proteins were readily detected throughout the brain including autonomic nervous system (ANS) control centers and spinal cord. However, despite presence of viral RNA and proteins, majority of the brain and spinal cord tissues exhibited minimal or no microscopic lesions. The virus tropism was restricted primarily to neurons, and virus particles (~61–68 nm) were present within axons of neurons and throughout the extracellular spaces. However, active virus replication was absent or minimal in majority of the brain and was limited to regions proximal to the olfactory tract. These data suggest that EEEV initially replicates in/near the olfactory bulb following aerosol challenge and is rapidly transported to distal regions of the brain by exploiting the neuronal axonal transport system to facilitate neuron-to-neuron spread. Once within the brain, the virus gains access to the ANS control centers likely leading to disruption and/or dysregulation of critical physiological parameters to produce severe disease. Moreover, the absence of microscopic lesions strongly suggests that the underlying mechanism of EEEV pathogenesis is due to neuronal dysfunction rather than neuronal death. This study is the first comprehensive investigation into EEEV pathology in a NHP model and will provide significant insights into the evaluation of countermeasure.  相似文献   
267.
Optimal and orthogonal Latin hypercube designs for computer experiments   总被引:1,自引:0,他引:1  
Butler  Neil A. 《Biometrika》2001,88(3):847-857
  相似文献   
268.
269.
ObjectiveTo investigate the association between migraine and ischaemic or haemorrhagic stroke in young women.DesignHospital based case-control study.SettingFive European centres participating in the World Health Organisation Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception.Subjects291 women aged 20-44 years with ischaemic, haemorrhagic, or unclassified arterial stroke compared with 736 age and hospital matched controls.InterventionQuestionnaire.ResultsAdjusted odds ratios associated with a personal history of migraine were 1.78 (95% confidence intervals, 1.14 to 2.77), 3.54 (1.30 to 9.61), and 1.10 (0.63 to 1.94) for all stroke, ischaemic stroke, and haemorrhagic stroke respectively. Odds ratios for ischaemic stroke were similar for classical migraine (with aura) (3.81, 1.26 to 11.5) and simple migraine (without aura) (2.97, 0.66 to 13.5). A family history of migraine, irrespective of personal history, was also associated with increased odds ratios, not only for ischaemic stroke but also haemorrhagic stroke. In migrainous women, coexistent use of oral contraceptives or a history of high blood pressure or smoking had greater than multiplicative effects on the odds ratios for ischaemic stroke associated with migraine alone. Change in the frequency or type of migraine on using oral contraceptives did not predict subsequent stroke. Between 20% and 40% of strokes in women with migraine seemed to develop directly from a migraine attack.ConclusionsMigraine in women of childbearing age significantly increases the risk of ischaemic but not haemorrhagic stroke. The coexistence of oral contraceptive use, high blood pressure, or smoking seems to exert a greater than multiplicative effect on the risk of ischaemic stroke associated with migraine.

Key messages

  • A personal history of migraine was associated with increased risk of ischaemic but not haemorrhagic stroke
  • Coexistence of risk factors—use of oral contraceptives, high blood pressure, or smoking had more than multiplicative effects on odds ratios for ischaemic stroke associated with migraine alone
  • A family history of migraine, irrespective of a personal migraine history, was associated with increased risk of ischaemic and haemorrhagic stroke
  • Up to 40% of strokes in migrainous women develop directly out of a migraine attack—so called migrainous strokes
  • A change in type or frequency of migraine with use of oral contraceptives did not predict subsequent stroke
  相似文献   
270.
The oligo-O-acetylation of sialic acids found in normal colonic mucins is greatly reduced in colorectal cancer. Mucins prepared from cancer tissue in adenocarcinoma showed this reduction, while normal O-acetylation was detected in resection margin and control cases and total mucin sialic acid content was significantly decreased in cancer vs control samples. A reduction of the O-acetyl transferase activity catalysing the O-acetylation reaction was also found. A series of cultured human colorectal cell lines derived from the same premalignant adenomatous line, and representative of the adenoma-carcinoma sequence were examined and revealed a depletion of oligo-O-acetylation in the original diploid premalignant line, re-expression in a further premalignant line and reduction in malignant mucinous and adenocarcinoma cell lines. Reduction of sialic acid O-acetylation appears as an early event in the process of malignant transformation in human colorectal cancer.  相似文献   
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