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991.
992.
Summary An echovirus type 30 (E30) outbreak occurred in Taiwan in 2001. In this study, one 1998 and nineteen 2001 enterovirus isolates
from cerebrospinal fluid (CSF) of children with meningitis were genetically analyzed. Although negative results were obtained
using the E30-specific monoclocal antibody in an immunofluorescent assay (IFA) test of all 20 isolates, molecular typing by
partial VP1 sequences and subsequent neutralization test identified them as E30. Among those, seven of them were misidentified
as echovirus type 4 (E4) when E4-specific monoclonal antibody was used. Complete genome sequences of one E30 isolate (TW-2513)
that were IFA-positive to E4 and another (TW-3182) that was IFA-negative to both E30 and E4 were determined and analyzed.
The overall percentage nucleotide identity in the structural coding region (P1) between these two isolates is 98.4, while
those in the nonstructural regions P2 and P3 are only 83.2 and 84.4, respectively, indicating that the two 2001 Taiwanese
E30 strains were probably recombinant. Recombination analysis of these two E30 genomes revealed that their genome structures
are mosaic, which might have been formed gradually and frequently over time. 相似文献
993.
Goldstein AM Chan M Harland M Hayward NK Demenais F Bishop DT Azizi E Bergman W Bianchi-Scarra G Bruno W Calista D Albright LA Chaudru V Chompret A Cuellar F Elder DE Ghiorzo P Gillanders EM Gruis NA Hansson J Hogg D Holland EA Kanetsky PA Kefford RF Landi MT Lang J Leachman SA MacKie RM Magnusson V Mann GJ Bishop JN Palmer JM Puig S Puig-Butille JA Stark M Tsao H Tucker MA Whitaker L Yakobson E;Lund Melanoma Study Group;Melanoma Genetics Consortium 《Journal of medical genetics》2007,44(2):99-106
Background
The major factors individually reported to be associated with an increased frequency of CDKN2A mutations are increased number of patients with melanoma in a family, early age at melanoma diagnosis, and family members with multiple primary melanomas (MPM) or pancreatic cancer.Methods
These four features were examined in 385 families with ⩾3 patients with melanoma pooled by 17 GenoMEL groups, and these attributes were compared across continents.Results
Overall, 39% of families had CDKN2A mutations ranging from 20% (32/162) in Australia to 45% (29/65) in North America to 57% (89/157) in Europe. All four features in each group, except pancreatic cancer in Australia (p = 0.38), individually showed significant associations with CDKN2A mutations, but the effects varied widely across continents. Multivariate examination also showed different predictors of mutation risk across continents. In Australian families, ⩾2 patients with MPM, median age at melanoma diagnosis ⩽40 years and ⩾6 patients with melanoma in a family jointly predicted the mutation risk. In European families, all four factors concurrently predicted the risk, but with less stringent criteria than in Australia. In North American families, only ⩾1 patient with MPM and age at diagnosis ⩽40 years simultaneously predicted the mutation risk.Conclusions
The variation in CDKN2A mutations for the four features across continents is consistent with the lower melanoma incidence rates in Europe and higher rates of sporadic melanoma in Australia. The lack of a pancreatic cancer–CDKN2A mutation relationship in Australia probably reflects the divergent spectrum of mutations in families from Australia versus those from North America and Europe. GenoMEL is exploring candidate host, genetic and/or environmental risk factors to better understand the variation observed. 相似文献994.
Conserved characteristics of the rhabdovirus nucleoprotein 总被引:1,自引:1,他引:0
Rhabdovirus is a negative strand RNA virus that packages a ribonucleoprotein (RNP) complex. The RNP is composed of a genome that is encapsidated completely by the nucleoprotein (N). Structural comparisons of the RNA-nucleoprotein complexes from two members, vesicular stomatitis virus (VSV) and rabies virus (RABV), revealed highly conserved characteristics of folding, RNA binding, and assembly despite their lack of significant homology in amino acid sequence. The RNA binding cavity is located between two conserved domains formed by alpha-helices, but the positively charged residues that coordinate with the phosphate groups are at different sites. The intermolecular interactions among N molecules have a conserved pattern that is rendered, however, by different residues. The curvature of the RABV N-RNA complex in the crystal structure is larger than that of the VSV N-RNA complex. The more relaxed curvature allows the bases in the RNA to stack more tightly, and at the same time, the helices near the C-terminus move into the created space in order to cover the bound RNA. This may explain how the RNP can adopt different conformations from being packed as a superhelix in the virion to a relaxed linear structure once being delivered into the cytoplasm. 相似文献
995.
996.
Alexander Augustyn Daniel L. Adams Jianzhong He Yawei Qiao Vivek Verma Zhongxing Liao Cha-Mei Tang John V. Heymach Anne S. Tsao Steven H. Lin 《Clinical lung cancer》2021,22(3):e451-e465
BackgroundCancer-associated macrophage-like cells (CAMLs) are a potential peripheral blood biomarker for disease progression. This study used data from a phase 2 clinical trial to evaluate prognostic utility of CAMLs for locally advanced non–small-cell lung cancer treated with definitive chemoradiotherapy (CRT) and atezolizumab (DETERRED; ClinicalTrials.gov NCT02525757).Patients and MethodsSample collection occurred at baseline (T0), during CRT (T1), at end of CRT (T2), and at first follow-up (T3). CAMLs were captured and quantified by the CellSieve system using multiplex immunostaining. Giant CAMLs were defined as characteristic CAMLs ≥ 50 μm. Kaplan-Meier methodology estimated progression-free survival, distant failure-free survival, relapse-free survival, and overall survival at 30 months.ResultsThirty-nine patients were evaluated between December 2015 and March 2018. Median follow-up was 27 months. Most disease was stage III (85%) and comprised squamous-cell carcinoma (38%) or adenocarcinoma (59%). In total, 267 blood samples were analyzed. Giant CAMLs were identified in 57%, 60%, 64%, and 63% of patients at T0, T1, T2, and T3, respectively. Patients with giant CAMLs at T3, occurring at a median of 30 days after completion of CRT, had significantly worse distant failure-free survival (hazard ratio [HR] 4.9, P = .015), progression-free survival (HR 2.5, P = .025), recurrence-free survival (HR 2.4, P = .036), and overall survival (HR 3.5, P = .034) compared to patients with small or no CAMLs.ConclusionsPresence of giant CAMLs after CRT completion was associated with development of metastatic disease and poorer survival despite the use of maintenance immunotherapy. Monitoring CAMLs may help risk-stratify patients for adaptive treatment strategies. 相似文献
997.
The purpose of this study is to evaluate the non-ionizing radiation (NIR) exposure, especially optical radiation levels, and potential health hazard from aluminum arc welding processes based on the American Conference of Governmental Industrial Hygienists (ACGIH) method. The irradiance from the optical radiation emissions can be calculated with various biological effective parameters [i.e., S(lambda), B(lambda), R(lambda)] for NIR hazard assessments. The aluminum arc welding processing scatters bright light with NIR emission including ultraviolet radiation (UVR), visible, and infrared spectra. The UVR effective irradiance (Eeff) has a mean value of 1,100 microW cm at 100 cm distance from the arc spot. The maximum allowance time (tmax) is 2.79 s according to the ACGIH guideline. Blue-light hazard effective irradiance (EBlue) has a mean value of 1840 microW cm (300-700 nm) at 100 cm with a tmax of 5.45 s exposure allowance. Retinal thermal hazard effective calculation shows mean values of 320 mW cm(-2) sr(-1) and 25.4 mW (cm-2) (380-875 nm) for LRetina (spectral radiance) and ERetina (spectral irradiance), respectively. From this study, the NIR measurement from welding optical radiation emissions has been established to evaluate separate types of hazards to the eye and skin simultaneously. The NIR exposure assessment can be applied to other optical emissions from industrial sources. The data from welding assessment strongly suggest employees involved in aluminum welding processing must be fitted with appropriate personal protection devices such as masks and gloves to prevent serious injuries of the skin and eyes upon intense optical exposure. 相似文献
998.
The quantitative determination of estrogen and progesterone receptors (PR and ER) in breast tumor cytosol has been routinely performed in clinical laboratories to aid in the selection between hormonal and chemotherapy and also to predict prognosis. However, the small amount of tissue available from the increasingly popular fine-needle aspiration and core biopsies from breast cancer patients requires more sensitive immunoassays for receptor quantification. We have developed two sensitive immuno-assays for ER and PR on microplate with the use of recently available anti-ER and anti-PR antibodies of higher affinity and a powerful signal magnification agent, namely Amdex. The calibrator was a pooled breast tumor cytosol used as calibrator and calibrated against Abbott kits. The protein concentration of the cytosol and the upper normal cutoffs for our assays were reduced to approximately 0.2 mg/mL and 3 fmol/0.2 mg/mL, respectively. Both assays have sensitivities close to 1 fmol/mL, which are sufficiently sensitive for the receptor quantification in fine-needle aspiration biopsies and cord biopsies of breast tumor. 相似文献
999.
1000.
Hsuan-Yin Ma Chun-Yi Lu Kuo-Chien Tsao Hsiu-Ming Shih Ai-Ling Cheng Li-Min Huang Luan-Yin Chang 《Journal of microbiology, immunology, and infection》2018,51(5):608-613