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991.
Mark K. Brannon J. Muse Davis Jonathan R. Mathias Chris J. Hall Julia C. Emerson Philip S. Crosier Anna Huttenlocher Lalita Ramakrishnan Samuel M. Moskowitz 《Cellular microbiology》2009,11(5):755-768
Pseudomonas aeruginosa is an opportunistic human pathogen that can cause serious infection in those with deficient or impaired phagocytes. We have developed the optically transparent and genetically tractable zebrafish embryo as a model for systemic P. aeruginosa infection. Despite lacking adaptive immunity at this developmental stage, zebrafish embryos were highly resistant to P. aeruginosa infection, but as in humans, phagocyte depletion dramatically increased their susceptibility. The virulence of an attenuated P. aeruginosa strain lacking a functional Type III secretion system was restored upon phagocyte depletion, suggesting that this system influences virulence through its effects on phagocytes. Intravital imaging revealed bacterial interactions with multiple blood cell types. Neutrophils and macrophages rapidly phagocytosed and killed P. aeruginosa , suggesting that both cell types play a role in protection against infection. Intravascular aggregation of erythrocytes and other blood cells with resultant circulatory blockage was observed immediately upon infection, which may be relevant to the pathogenesis of thrombotic complications of human P. aeruginosa infections. The real-time visualization capabilities and genetic tractability of the zebrafish infection model should enable elucidation of molecular and cellular details of P. aeruginosa pathogenesis in conditions associated with neutropenia or impaired phagocyte function. 相似文献
992.
Yaron J. Lidor Feng J. Xu Otoniel Martínez-Maza George J. Olt Jeffrey R. Marks Andrew Berchuck Sundaram Ramakrishnan Jonathan S. Berek Robert C. Bast Jr. 《Experimental cell research》1993,207(2)
Normal and neoplastic epithelial cells produce growth factors that can affect cells from different lineages. Epithelial ovarian cancers produce M-CSF and IL-6. In the present study, production of these cytokines has been measured in the apparently normal epithelial cells from which epithelial ovarian neoplasms are thought to arise. Epithelial cells from the surface of premenopausal human ovaries were established in short-term cultures. The cells bound anti-cytokeratin antibodies and exhibited characteristic epithelial morphology by light and transmission electron microscopy. M-CSF and IL-6 were detected in supernatants from cultures of these cells, using assays specific for each factor. Cytokine levels were comparable to those in supernatants from ovarian and breast cancer cell lines. M-CSF expression could also be demonstrated by immunohistochemical analysis with specific rabbit heteroantiserum. Thus, M-CSF and IL-6 are produced constitutively by normal as well as by neoplastic ovarian epithelium. 相似文献
993.
Riya Bhattacharya Vijay Parthasarthy Debajyoti Bose Khushabu Gulia Siddhant Srivastava Kadirvel Ramesh Roshan Ramakrishnan Shankar 《Biotechnology and bioengineering》2023,120(6):1455-1464
In plant microbial fuel cells (p-MFCs) electrochemically active microbes present around the plant root convert rhizodeposits or the organic matter into electrons, protons, and CO2. This work covers the increasing trend in research with p-MFCs with their mechanism of operation. Different plant species and their selection criteria are also covered. Furthermore, the long-term evaluation of such systems with its cost effectiveness and commercial and environmental perspectives are also presented. A critical aspect for bioelectricity production is the photosynthetic pathway of the plant. Additionally, the microbial communities and reactor configurations employed across different capacities are also reviewed. The challenges with bioelectricity production and the opportunity for developing p-MFCs in conjunction with traditional MFCs are also covered. These electrogenic reactor systems harness bioelectricity without harvesting the plant and has the capacity to utilize this energy for remote power applications. 相似文献
994.
Kevin K. Takaki Gabriel Rinaldi Matthew Berriman Antonio J. Pagán Lalita Ramakrishnan 《Cell host & microbe》2021,29(1):58-67.e5
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995.
996.
A total of 171 plant species used by the Nishis, the Hill M iris, the Sulungs, and the Apatanis of Lower Subansiri district of Arunachal Pradesh in northeastern India; 12 animal species used by the Nishis were identified. Of the total plant species recorded 38% of the total were leafy vegetables and 28% were edible fruits. Others were used for food, liquor, medicine, household goods, traditional dresses, dyes, tattoos, fish and animal poisons, or for salt extraction. The Sulungs use starch obtained from the pith ofMetroxylon sagu as a staple food. The extensive use of wild plants and animals suggests that the tribes of northeastern India rely heavily on forest resources. The importance of conserving these in the light of rapid conversion of rainforests is emphasized. 相似文献
997.
998.
Sophie Dream Sandra Park Tina W. Yen William Rilling Lisa Rein Kara Doffek James W. Findling Steven B. Magill Srividya Kidambi Douglas B. Evans Tracy S. Wang 《Endocrine practice》2022,28(3):276-281
ObjectiveIn patients with primary aldosteronism, adrenal venous sampling (AVS) is performed to determine the presence of unilateral or bilateral adrenal disease. During AVS, verification of catheter positioning within the left adrenal vein (AV) and the right AV by comparison of AV and inferior vena cava (IVC) cortisol levels can be variable. The objective of this study was to determine the utility of AV epinephrine levels in assessing successful AV cannulation.MethodsThis was a single institution, retrospective review of patients who underwent AVS with cosyntropin stimulation for primary aldosteronism between 2009 and 2018. Successful cannulation of the AV was defined by an AV/IVC cortisol ratio selectivity index (SI) ≥3:1. Epinephrine thresholds to predict catheter placement in the AV were determined using logistic regression. The calculated epinephrine thresholds were compared with previously published thresholds.ResultsAVS was performed on 101 consecutive patients and, based on the SI, successful cannulation of the left AV and right AV occurred in 98 (97%) and 91(90%) patients, respectively. The calculated optimal epinephrine threshold to predict AV cannulation was 364 pg/mL (sensitivity, 92.1%; specificity, 94.6%) and the calculated optimal AV/IVC epinephrine ratio threshold was 27.4, (sensitivity, 92.1%; specificity, 91.3%). Among the 14 patients with failed AV cannulation, 3 patients would have been considered to have successful AVS using AV epinephrine levels >364 pg/mL and AV/IVC epinephrine ratio >27.4 thresholds.ConclusionObtaining 2 right AV samples routinely as well as AV and IVC epinephrine levels during AVS could prevent unnecessary repeat AVS in patients with failed AV cannulation based on cortisol-based SI <3:1. 相似文献
999.
1000.