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91.
BACKGROUND: Osmotic nephrosis is a form of renal tubular injury that has been found in patients treated with intravenous immunoglobulin (IVIG). CASE: A 46-year-old male who had two courses of chemotherapy for acute myelogenous leukemia was found to have refractory thrombocytopenia. After IVIG (Sandoglobulin 12%, Novartis) administration (1 g/kg) for five consecutive days, the patient became oliguric and eventually anuric on the fifth dose. Hemodialysis was initiated, and urine production was noted on day 2 of hospitalization. Routine cytologic examination of fresh, voided urine showed numerous macrophagelike, bland epithelial cells with abundant, multivacuolated cytoplasm. Cytokeratin immunostain revealed positivity, thus confirming the epithelial origin of these cells. CONCLUSION: To our knowledge, this is the first such case reported in the English-language cytology literature. Awareness of a patient's clinical history may be helpful in avoiding an incorrect diagnosis. Urine cytology may be useful in obtaining an early diagnosis of osmotic nephrosis in patients receiving high-dose IVIG therapy that may eliminate the need for a renal biopsy.  相似文献   
92.
Lithium–sulfur (Li–S) batteries are promising candidates for energy storage, but suffer from capacity and cycling challenges caused by the serious shuttling effect of polysulfide (PS) ions. To address these issues, a sodium alginate (SA)‐derived affinity laminated chromatography membrane built‐in electrode is designed. This is the first attempt to utilize this type of membrane, which is widely used for the selective adsorption of proteins, in the battery field. An ordered multilayer structure throughout the electrode can easily be obtained, and the number of membrane layers can be also conveniently controlled by varying the cross‐linking time of SA. The PS shuttling effect is efficiently suppressed and the permeability of PSs is reduced by enveloping the carbon/sulfur powder in ultrathin laminated chromatography membranes. As a result, these designed electrodes deliver a superhigh initial capacity of 1492 mA h g?1, with a capacity retention almost 20% higher than the contrast. This low‐cost and easily mass‐producible strategy inspired by affinity chromatography is expected to effectively solve the PS shuttling problem toward high‐loading and long‐lifetime Li–S batteries in practice.  相似文献   
93.
The interfacial instability between a thiophosphate solid electrolyte and oxide cathodes results in rapid capacity fade and has driven the need for cathode coatings. In this work, the stability, evolution, and performance of uncoated, Li2ZrO3‐coated, and Li3B11O18‐coated LiNi0.5Co0.2Mn0.3O2 cathodes are compared using first‐principles computations and electron microscopy characterization. Li3B11O18 is identified as a superior coating that exhibits excellent oxidation/chemical stability, leading to substantially improved performance over cells with Li2ZrO3‐coated or uncoated cathodes. The chemical and structural origin of the different performance is interpreted using different microscopy techniques which enable the direct observation of the phase decomposition of the Li2ZrO3 coating. It is observed that Li is already extracted from the Li2ZrO3 in the first charge, leading to the formation of ZrO2 nanocrystallites with loss of protection of the cathode. After 50 cycles separated (Co, Ni)‐sulfides and Mn‐sulfides can be observed within the Li2ZrO3‐coated material. This work illustrates the severity of the interfacial reactions between a thiophosphate electrolyte and oxide cathode and shows the importance of using coating materials that are absolutely stable at high voltage.  相似文献   
94.
95.
In vitro drug testing requires long‐term maintenance of hepatocyte liver specific functions. Hepatocytes cultured at a higher seeding density in a sandwich configuration exhibit an increased level of liver specific functions when compared to low density cultures due to the better cell to cell contacts that promote long term maintenance of polarity and liver specific functions. However, culturing hepatocytes at high seeding densities in a standard 24‐well plate poses problems in terms of the mass transport of nutrients and oxygen to the cells. In view of this drawback, we have developed a polydimethylsiloxane (PDMS) bioreactor that was able to maintain the long‐term liver specific functions of a hepatocyte sandwich culture at a high seeding density. The bioreactor was fabricated with PDMS, an oxygen permeable material, which allowed direct oxygenation and perfusion to take place simultaneously. The mass transport of oxygen and the level of shear stress acting on the cells were analyzed by computational fluid dynamics (CFD). The combination of both direct oxygenation and perfusion has a synergistic effect on the liver specific function of a high density hepatocyte sandwich culture over a period of 9 days. Biotechnol. Bioeng. 2013; 110: 1663–1673. © 2012 Wiley Periodicals, Inc.  相似文献   
96.
In the initial step of sugar metabolism, sugar-specific transporters play a decisive role in the passage of sugars through plasma membranes into cytoplasm. The SecY complex (SecYEG) in bacteria forms a membrane channel responsible for protein translocation. The present work shows that permeabilized SecY channels can be used as nonspecific sugar transporters in Escherichia coli. SecY with the plug domain deleted allowed the passage of glucose, fructose, mannose, xylose, and arabinose, and, with additional pore-ring mutations, facilitated lactose transport, indicating that sugar passage via permeabilized SecY was independent of sugar stereospecificity. The engineered E. coli showed rapid growth on a wide spectrum of monosaccharides and benefited from the elimination of transport saturation, improvement in sugar tolerance, reduction in competitive inhibition, and prevention of carbon catabolite repression, which are usually encountered with native sugar uptake systems. The SecY channel is widespread in prokaryotes, so other bacteria may also be engineered to utilize this system for sugar uptake. The SecY channel thus provides a unique sugar passageway for future development of robust cell factories for biotechnological applications.  相似文献   
97.
Numbers of emerging evidence suggest that variable microRNA (miRNA) expression facilitates the aging process. In this study, we distinguished aberrant miRNA expression in aged skin and explored the biological functions and potential mechanism of upregulated miR-302b-3p. At first, miRNA microarray analysis was examined to explore miRNA expression profiling in the skin of aging mice model by D -galactose (d -gal) injection. We identified 29 aberrant miRNAs in aged mice skin. Next, KEGG enrichment analysis was conducted with DIANA-miPath v3.0, which was revealed that enrichment pathways involved in such processes as extracellular matrix-receptor interaction, MAPK signaling pathway, and mammalian target of rapamycin (mTOR) signaling pathway. The target genes of deregulated miRNAs were predicted from four bioinformatic algorithms (miRDB, Targetscan, miRwalk, and Tarbase). The interaction network of miRNAs and their targets were visualized using Cytoscape software. As a result, we found that some hub genes (including JNK2, AKT1/2/3, PAK7, TRPS1, BCL2L11, and IKZF2) were targeted by 12 potential miRNAs (including miR-302b-3p, miR-291a-5p, miR-139-3p, miR-467c-3p, miR-186-3p, etc.). Subsequently, we identified five upregulated miRNA via quantitative polymerase chain reaction and all of them were confirmed increased significantly in aged skin tissues compared with young control tissues. Among them, high expression of miR-302b-3p was verified in both aged skin tissues and senescence fibroblasts. Furthermore, miR-302b-3p mimic accelerated skin fibroblast senescence and suppressed the longevity-associated gene Sirtuin 1(Sirt1) expression, whereas miR-302b-3p inhibitor could delay skin fibroblast senescence and contribute Sirt1 expression. In addition, we demonstrated that c-Jun N-terminal kinase 2(JNK2) is a direct target of miR-302b-3p by a luciferase reporter assay. An inverse correlation was verified in fibroblasts between miR-302b-3p and JNK2. Most importantly, siRNA JNK2 confirmed that low expression of JNK2 could accelerate fibroblasts senescence. In conclusion, our results indicated that overexpressed miR-302b-3p plays an important biological role in accelerating skin aging process via directly targeting JNK2 gene.  相似文献   
98.
Shen  He  Wu  Shuyu  Chen  Xi  Xu  Bai  Ma  Dezun  Zhao  Yannan  Zhuang  Yan  Chen  Bing  Hou  Xianglin  Li  Jiayin  Cao  Yudong  Fu  Xianyong  Tan  Jun  Yin  Wen  Li  Juan  Meng  Li  Shi  Ya  Xiao  Zhifeng  Jiang  Xingjun  Dai  Jianwu 《中国科学:生命科学英文版》2020,63(12):1879-1886
Science China Life Sciences - Spinal cord injury (SCI), especially complete transected SCI, leads to loss of cells and extracellular matrix and functional impairments. In a previous study, we...  相似文献   
99.
F Zhu  XH Ma  C Qin  L Tao  X Liu  Z Shi  CL Zhang  CY Tan  YZ Chen  YY Jiang 《PloS one》2012,7(7):e39782
Due to extensive bioprospecting efforts of the past and technology factors, there have been questions about drug discovery prospect from untapped species. We analyzed recent trends of approved drugs derived from previously untapped species, which show no sign of untapped drug-productive species being near extinction and suggest high probability of deriving new drugs from new species in existing drug-productive species families and clusters. Case histories of recently approved drugs reveal useful strategies for deriving new drugs from the scaffolds and pharmacophores of the natural product leads of these untapped species. New technologies such as cryptic gene-cluster exploration may generate novel natural products with highly anticipated potential impact on drug discovery.  相似文献   
100.
Zhuang  G. S.  Wang  Y. S.  Tan  M. G.  Zhi  M.  Pan  W. Q.  Cheng  Y. D. 《Biological trace element research》1990,26(1):729-736

In order to study the relationships between trace element concentrations of hair and internal body burdens, a radiochemical NAA technique has been used for determination of the elements As, Cd, and Hg in autopsy samples of liver, kidney-cortex, lung, and hair from 24 male persons who died by accident. High significant positive correlations were observed between the As concentration in hair and in kidney-cortex, and between Cd and Zn concentrations in kidney-cortex. The contents of Cd, both for lung and kidney-cortex, were related to the smoking habits of the subjects.

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