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201.
Bone marrow endothelial progenitor cells activate hepatic stellate cells and aggravate carbon tetrachloride induced liver fibrosis in mice via paracrine factors 下载免费PDF全文
202.
Carys S. Kenway-Lynch Arpita Das Diganta Pan Andrew A. Lackner Bapi Pahar 《Journal of virology》2013,87(21):11916-11923
Loss of intestinal CD4+ T cells was associated with decreased production of several T-helper 1 (TH1) and TH2 cytokines and increased production of interleukin 17 (IL-17), gamma interferon (IFN-γ), CCL4, and granulocyte-macrophage colony-stimulating factor (GM-CSF) by CD8+ T cells 21 days after simian immunodeficiency virus (SIV) infection in rhesus macaques. Shifting of mucosal TH1 to TH2 or T-cytotoxic 1 (TC1) to TC2 cytokine profiles was not evident. Additionally, both CD4+ and CD8+ T cells showed upregulation of macrophage migration inhibition factor (MIF) and basic fibroblast growth factor (FGF-basic) cytokines that have been linked to HIV disease progression. 相似文献
203.
Arpita Das 《Bioethics》2020,34(6):585-592
Intersexuality, particularly in the global South, remains an under-researched field of study. In my in-progress doctoral research project, I explore the cultural, social, and medical discourses that influence how key stakeholders such as healthcare providers make decisions about the sex and gender assignment of the intersex child in India. In this paper I interrogate some of these ideas around gender assignment of intersex people in India, paying particular attention to the context of son preference. I am interested in exploring how decisions of gender assignment by medical professionals are guided by ideas of son preference. Focusing on four qualitative, semi-structured, in-depth interviews across two cities with medical doctors from different specializations, this paper is a preliminary attempt to examine some of the factors that guide medical professionals in making decisions about gender assignment of intersex children and explore the dynamics of the decision-making process. Specifically, I explore the factors that inform doctors’ decision-making and locate these decision-making processes within the broader socio-cultural context of India. 相似文献
204.
Arpita Roy 《Dialectical Anthropology》2012,36(3-4):291-316
On September 19, 2008, the Large Hadron Collider (LHC) at CERN, Switzerland, began the world’s highest energy experiments as a probe into the structure of matter and forces of nature. Just nine days after the gala start-up, an explosion occurred in the LHC tunnel that brought the epic collider to a complete standstill. In light of the catastrophic incident that disrupted the operation of the LHC, the paper investigates the relation of temporality to the cycle of work in science, and raises the question: What kind of methodological value should we ascribe to events such as crises or breakdowns? Drawing upon and integrating classical anthropological themes with two and a half years of fieldwork at the LHC particle accelerator complex, the paper explores how the incident in September, which affected the instrument, acquaints us with the distribution of work in the laboratory. The incident discloses that the organization of science is not a homogenous ensemble, but marked by an enormous diversity of tasks and personnel, at the heart of which lies the opposition of theory and practice, or pure and applied. This opposition not only forms the source and sanction of the intricate division of labor found in high-energy physics, but also provides a satisfactory answer to every question involving the interface of experimental science and engineering skill. 相似文献
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206.
Arpita Patel 《Soil & Sediment Contamination》2015,24(7):786-795
Chlorobenzene (CB), a dense nonaqeuous phase liquid (DNAPL), is categorized as a priority pollutant by the US EPA. It enters into ecosystems via solid and liquid waste discharge. Bioremediation is a key technique to remediate such contaminated sites. The present study aimed to isolate a chlorobenzene-degrading bacterium, determine the metabolic pathway for chlorobenzene degradation, and characterize biosurfactant production. Microbacterium sp. strain TAS1CB was isolated from contaminated sites and identified by 16S rRNA gene sequencing. Cells possessing positive chemotaxis for CB indicated their ability to degrade CB. Cells degraded CB via production of chlorobenzene dioxygenase, which converted CB to chlorocatechol. Chlorobenzene dioxygenase production was higher at 7 pH and 30°C. Intermediate metabolite analysis by UV scanning, HPLC, and GC-MS analysis revealed production of chlorocatechol and cis-cis muconate. Thus, Microbacterium was able to degrade CB via an ortho-cleavage pathway. In addition to chlorobenzene dioxygenase production, cells also produced biosurfactant which pseudosolubilized CB and increased degradation rate. Chemical characterization showed it to be a glycolipid-type biosurfactant. A phytotoxity study showed 60% of toxicity decreased after 72 hrs of degradation by isolate. 相似文献
207.
208.
Danny Reible Don Hayes Cecil Lue-Hing James Patterson Nani Bhowmik Martin Johnson 《Soil & Sediment Contamination》2003,12(3):325-344
The long-term potential risks of environmental dredging vs. in situ contaminated sediment management practices are discussed and compared for the Lower Fox River, Wisconsin. The risks are identified as being largely associated with the residual sediment contamination associated with either approach. The integral of the surface area-weighted average contaminant concentration in surface sediment is proposed as a metric to compare these risks. Capping is shown to exhibit significantly reduced exposure and risk relative to the dredging scenarios, even if potential undetected erosion of 5% of the cap is considered. Even with the improbable event of undetected failure of 25% of the cap, the exposure and risk associated with capping is approximately equal to or below all dredging scenarios. A preference for dredging due to the perception that it eliminates the long-term risk of in situ capping is not supported by this analysis. Although strictly applicable only to the Lower Fox River, the results suggest sitespecific analyses must be conducted to determine which sediment management approaches minimize the potential for long-term exposure and risk. 相似文献
209.
Venus Singh Mithu Bidyut Sarkar Debanjan Bhowmik Muralidharan Chandrakesan Sudipta Maiti Perunthiruthy K. Madhu 《Biophysical journal》2011,(11):2825
Observations like high Zn2+ concentrations in senile plaques found in the brains of Alzheimer's patients and evidences emphasizing the role of Zn2+ in amyloid-β (Aβ)-induced toxicity have triggered wide interest in understanding the nature of Zn2+-Aβ interaction. In vivo and in vitro studies have shown that aggregation kinetics, toxicity, and morphology of Aβ aggregates are perturbed in the presence of Zn2+. Structural studies have revealed that Zn2+ has a binding site in the N-terminal region of monomeric Aβ, but not much is precisely known about the nature of binding of Zn2+ with aggregated forms of Aβ or its effect on the molecular structure of these aggregates. Here, we explore this aspect of the Zn2+-Aβ interaction using one- and two-dimensional 13C and 15N solid-state NMR. We find that Zn2+ causes major structural changes in the N-terminal and the loop region connecting the two β-sheets. It breaks the salt bridge between the side chains of Asp23 and Lys28 by driving these residues into nonsalt-bridge-forming conformations. However, the cross-β structure of Aβ42 aggregates remains unperturbed though the fibrillar morphology changes distinctly. We conclude that the salt bridge is not important for defining the characteristic molecular architecture of Aβ42 but is significant for determining its fibrillar morphology and toxicity. 相似文献
210.
Arpita Jana Malabika Nayak Supriya Dutta Sasankasekhar Mohanta 《Inorganica chimica acta》2011,365(1):71-214
Reaction of [CuIIL⊂(H2O)] (H2L = N,N′-ethylenebis(3-ethoxysalicylaldimine)) with nickel(II) perchlorate in 1:1 ratio in acetone produces the trinuclear compound [(CuIIL)2NiII(H2O)2](ClO4)2 (1). On the other hand, on changing the solvent from acetone to methanol, reaction of the same reactants in same ratio produces the pentametallic compound [(CuIIL)2NiII(H2O)2](ClO4)2·2[CuIIL⊂(H2O)]·2MeOH (2A), which loses solvated methanol molecules immediately after its isolation to form [(CuIIL)2NiII(H2O)2](ClO4)2·2[CuIIL⊂(H2O)] (2B). Clearly, formation of 1 versus 2A and 2B is solvent dependent. Crystal structures of 1 and 2A have been determined. Interestingly, compound 2A is a [3 × 1 + 1 × 2] cocrystal. The cryomagnetic profiles of 1 and 2B indicate that the two pairs of copper(II)···nickel(II) ions in the trinuclear cores in both the complexes are coupled by almost identical moderate antiferromagnetic interaction (J = −22.8 cm−1 for 1 and −26.0 cm−1 for 2B). 相似文献