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51.
Summary Capsid polypeptides of all six types (B1–6) of group B coxsackieviruses were compared by high-resolution gel electrophoresis, and synthesis of protein and RNA in B4- or B5-infected HeLa cells was analyzed. Four polypeptides, VP1–4, were detected in each type. Another polypeptide, VP0, slightly larger than VP1, was also detected in trace amounts in some types. VP1–3 showed different but characteristic molecular weights (VP1, 34,500 to 37,000; VP2, 31,000 to 36,000; VP3, 26,000 to 32,500), and presented well-defined and reproducible differences in electrophoretic mobility. The molecular weight of VP4 ranged from 5,000 to 5,500. VP1 was largest in B2 and B4, smallest in B1, and of intermediate size in the other types. VP2 was largest in B4 and smallest in B2; VP3 was largest in B5 and B6 and smallest in B4. In B4- or B5-infected HeLa cells, host protein synthesis began to decline after 2 hours postinfection and was less than 20 percent of the control by 6 hours postinfection. Actinomycin D-resistant viral RNA synthesis started at about 2 hours postinfection, peaked by 5 hours, and then declined rapidly. Virus-specific protein synthesis began while host protein synthesis was declining, increased during the ensuing period, and declined in late infection. A number of virus-specific proteins with molecular weights from 23,500 to >92,500 were detected in the host cytoplasm. At least three of these proteins were also present in the nucleus. The kinetics of processing of virus-specific proteins were examined by pulse-chase experiments in B5-infected cells. The relative intensities of [35S]-methionine-labeled polypeptides suggest that a number of smaller, stable chains (MW 23,500 to 38,000) are generated by cleavage of a precursor polypeptide (MW 92,500 to 100,000).With 7 Figures 相似文献
52.
Satyanarayana S Kalghatgi AT Malaviya AK Bhardwaj JR Muralidhar A Jawed KZ Chatterjee T Trehan A Sirohi D 《Indian journal of pathology & microbiology》2003,46(3):416-419
The value of autopsy in understanding the natural course of any disease is beyond any argument. The reluctance of pathologists to perform autopsy in HIV infected cadavers is justified due to the risks involved to the prosector and the morgue attendants. A relative low risk needle necropsy protocol is proposed using fine needle aspiration cytology, tru-cut biopsies and microbiological examination. Diagnosis could be offered in all the forty-four needle necropsies performed. Disseminated tuberculosis in 18/44 (40.9%) cases, disseminated cryptococcosis in 12/44 (27.2%) cases, poly-microbial infections in 27.2% cases and non-Hodgkin's lymphoma in 9% cases were detected in the study. Infectious agents like Histoplasma capsulatum, Isospora belli, tachyzoites of Toxoplasma gondii, Candida sp and Cryptococcus sp could be demonstrated in the samples obtained in the study. Lack of material for study of gross pathology, inaccessibility of deep-seated lesions and risk of needle stick injury to the prosector though low are the limitations of this procedure. 相似文献
53.
The significant advances in our understanding of color vision has been due to the convergence of information from behavioral
and molecular genetic analyses. The molecular biology of the visual pigments; molecular genetic basis of variation in normal
and abnormal color vision, and regulation of the genes at the LWS-MWS pigment gene locus are discussed. 相似文献
54.
Elena Formisano Andrea Pasta Anna Laura Cremonini Ilaria Di Lorenzo Samir Giuseppe Sukkar Livia Pisciotta 《Nutrients》2021,13(4)
Background: Dyslipidemia is one of the major causes of atherosclerotic cardiovascular disease (ASCVD) and a Mediterranean Diet (MD) is recommended for its prevention. The objectives of this study were to evaluate adherence to an MD at baseline and follow-up, in a cohort of dyslipidemic patients, and to evaluate how different food intakes can influence lipid profile, especially how different sources of saturated fatty acids impact lipid phenotype. Methods: A retrospective analysis was conducted on 106 dyslipidemic patients. Clinical characteristics, lipid profile, and food habits data were collected at baseline and after three months of follow-up with counseling. Adherence to an MD was evaluated with a validated food-frequency questionnaire (MEDI-LITE score). Results: The cross-sectional analysis showed that higher consumption of dairy products correlated independently with higher levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) and with lower triglycerides (TG) levels. Instead, lower HDL-C and TG levels and higher TC levels were independently associated with higher consumption of meat products. Adherence to an MD significantly improved after the follow-up period, from a mean value of 10 ± 3 (median 10, IQR 8–12) to 13 ± 2 (median 14, IQR 12–15), p < 0.0001. Conclusions: Dyslipidemic patients benefit from counseling for improving their adherence to an MD. The high intake of dairy products was associated with less atherogenic hyperlipidemia, which was characterized by higher levels of TC and HDL-C as compared withs the intake of an excessive amount of meat products, which was associated with higher levels of TC and TG and lower levels of HDL-C. 相似文献
55.
Vikram Sharma Kevin Chen Shehab A.R. Alansari Beni Verma Edward G. Soltesz Douglas R. Johnston Michael Zhen-Yu Tong Eric E. Roselli Per Wierup Gösta B. Pettersson A. Marc Gillinov Stephen G. Ellis Conrad Simpfendorfer Eugene H. Blackstone Samir Kapadia Lars G. Svensson Faisal G. Bakaeen 《The Annals of thoracic surgery》2021,111(5):1494-1501
56.
Richard E Overman Cory N Criss Zubin J Modi Samir K Gadepalli 《Journal of pediatric surgery》2021,56(2):328-331
IntroductionAutosomal recessive polycystic kidney disease (ARPKD) is a rare cause of renal failure with a highly variable clinical course. Patients who are symptomatic early in life frequently require early nephrectomy and peritoneal dialysis. In these patients there are little data to guide clinicians on whether to select unilateral nephrectomy or bilateral nephrectomy at the initial operative intervention. We review our experience with this disease process.MethodsA retrospective review was performed of 11 patients at our institution with ARPKD symptomatic within the first month of life. Charts were reviewed for relevant clinical data, and patients were divided into groups based on undergoing either unilateral or bilateral nephrectomy at their initial intervention. The decision for unilateral versus bilateral nephrectomy was decided by the clinical team without any available guidelines.ResultsOf the 11 patients reviewed, two patients died within the first two weeks from other complications. The remaining 9 all required nephrectomy, with 5 undergoing synchronous bilateral nephrectomy, and 4 undergoing initial unilateral nephrectomy. All four patients required removal of their contralateral kidney, a median of 25.5 days later. There was no difference in mortality, ventilator free days, or time to full feeds between the two groups, although the group undergoing initial unilateral nephrectomy had more TPN days than their counterparts (28 vs 17 days, p = 0.014).ConclusionsIn our cohort, there were few significant differences between the groups based on choice of initial unilateral or bilateral nephrectomy, and all children ultimately required removal of both kidneys. These data suggest that anesthetic exposures and other clinical outcomes might be optimized by initial bilateral nephrectomy.Level of evidenceIII. 相似文献
57.
58.
Kyriakos Chatzopoulos Sotiris Sotiriou Andrea R. Collins Panagiotis Kartsidis Alessandra C. Schmitt Xianfeng Chen Khashayarsha Khazaie Michael L. Hinni Colleen A. Ramsower Matthew A. Zarka Samir H. Patel Joaquin J. Garcia 《Head and neck pathology》2021,15(2):509
The tumor immune microenvironment of oral tongue squamous cell carcinoma may be accountable for differences in clinical behavior, particularly between different age groups. We performed RNA expression profiling and evaluated tumor infiltrating lymphocytes (TILs) and their T-cell subsets in order to assess the functional status of oral tongue squamous cell carcinoma tumor microenvironment and detect potentially clinically useful associations. Archival surgical pathology material from sixteen oral tongue squamous cell carcinoma patients was microscopically evaluated for TIL densities. RNA was extracted from macrodissected whole tumor sections and normal controls and RNA expression profiling was performed by the NanoString PanCancer IO 360 Gene Expression Panel. Immunostains for CD4, CD8 and FOXP3 were evaluated manually and by digital image analysis. Oral tongue squamous cell carcinomas had increased TIL densities, numerically dominated by CD4 + T cells, followed by CD8 + and FOXP3 + T cells. RNA expression profiling of tumors versus normal controls showed tumor signature upregulation in inhibitory immune signaling (CTLA4, TIGIT and PD-L2), followed by inhibitory tumor mechanisms (IDO1, TGF-β, B7-H3 and PD-L1). Patients older than 44 years showed a tumor microenvironment with increased Tregs and CTLA4 expression. Immunohistochemically assessed CD8% correlated well with molecular signatures related to CD8 + cytotoxic T-cell functions. FOXP3% correlated significantly with CTLA4 upregulation. CTLA4 molecular signature could be predicted by FOXP3% assessed by immunohistochemistry (R2 = 0.619, p = 0.026). Oral tongue squamous cell carcinoma hosts a complex inhibitory immune microenvironment, partially reflected in immunohistochemically quantified CD8 + and FOXP3 + T-cell subsets. Immunohistochemistry can be a useful screening tool for detecting tumors with upregulated expression of the targetable molecule CTLA4.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01229-w) contains supplementary material, which is available to authorized users. 相似文献
59.
Identification of a new genotype H wild-type mumps virus strain and its molecular relatedness to other virulent and attenuated strains 总被引:6,自引:0,他引:6
A single clinical isolate of mumps virus designated 88-1961 was obtained from a patient hospitalized with a clinical history of upper respiratory tract infection, parotitis, severe headache, fever and lymphadenopathy. We have sequenced the full-length genome of 88-1961 and compared it against all available full-length sequences of mumps virus. Based upon its nucleotide sequence of the SH gene 88-1961 was identified as a genotype H mumps strain. The overall extent of nucleotide and amino acid differences between each individual gene and protein of 88-1961 and the full-length mumps samples showed that the missense to silent ratios were unevenly distributed. Upon evaluation of the consensus sequence of 88-1961, four positions were found to be clearly heterogeneous at the nucleotide level (NP 315C/T, NP 318C/T, F 271A/C, and HN 855C/T). Sequence analysis revealed that the amino acid sequences for the NP, M, and the L protein were the most conserved, whereas the SH protein exhibited the highest variability among the compared mumps genotypes A, B, and G. No identifying molecular patterns in the non-coding (intergenic) or coding regions of 88-1961 were found when we compared it against relatively virulent (Urabe AM9 B, Glouc1/UK96, 87-1004 and 87-1005) and non-virulent mumps strains (Jeryl Lynn and all Urabe Am9 A substrains). 相似文献
60.
A computer-optimized experimental design was used to study the effect of incorporating a "super disintegrant", croscarmellose sodium, intragranularly, extragranularly, or distributed equally between the two phases of a tablet in which a poorly soluble drug constituted at least 92.5% of the formulation. The results were analyzed by means of a general quadratic response surface model and suggest that tablets with the same total concentration of super disintegrant dissolve at a faster rate when the super disintegrant is included intragranularly. Tablet friability was not affected by the method of super disintegrant incorporation. 相似文献