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141.
Kalyanasundaram Aravindan Henry Cassandra Brym Matthew Z. Kendall Ronald J. 《Parasitology research》2018,117(9):2963-2969
Parasitology Research - Physaloptera spp. are common nematodes found in the stomach and muscles of mammals, reptiles, amphibians, and birds. Physaloptera spp. have a complicated life cycle with... 相似文献
142.
Maternal cocaine use during pregnancy continues to be of great concern for health care professionals. Research in this area has increased as investigators examine the effects of prenatal cocaine exposure in the infant/young child. This paper will critically review the literature, identify the primary care needs of infants and young children with a known history of prenatal cocaine exposure, and present guidelines for the primary care practitioner to monitor the infant's physiologic and developmental sequelae during the first 3 years of life. Findings in the literature demonstrate inconsistencies in regard to the physiologic and developmental outcomes of infants/young children prenatally exposed to cocaine. Further research is warranted, as it is evident from studies that not all investigators are controlling for confounding variables such as poly-drug use, which is necessary in isolating cocaine's effects. Subtle effects, however, have been reported from well-controlled studies and, thus, particular attention needs to be paid to early identification and interventions by primary care practitioners to prevent negative health outcomes. The guidelines proposed assist the practitioner with a thorough and focused approach to assessing the physiologic and developmental effects that are currently known to occur in the infant/young child prenatally exposed to cocaine. 相似文献
143.
Annemarie Steiner Cassandra R. Harapas Seth L. Masters Sophia Davidson 《Current rheumatology reports》2018,20(7):39
Purpose of Review
The nuclear factor κB (NF-κB) pathway is tightly regulated through multiple posttranslational mechanisms including ubiquitination. Mutations in these regulatory pathways can cause disease and are the focus of this review.Recent Findings
The linear ubiquitin chain assembly complex (LUBAC) is a trimer made up of HOIL-1L, SHARPIN, and the catalytic subunit HOIP. Loss of function mutations in HOIL-1L and HOIP result in largely overlapping phenotypes, characterized by multi-organ autoinflammation, immunodeficiency, and amylopectinosis. Interestingly, patient fibroblasts exhibited diminished IL-1β- and TNF-induced NF-κB activation, yet monocytes were hyper-responsive to IL-1β, hinting at cell type or target specific roles of LUBAC-mediated ubiquitination. Ubiquitin-driven signaling is counterbalanced by deubiquitinase enzymes (DUBs), such as OTULIN and A20. Hypomorphic mutations in OTULIN result in elevated NF-κB signaling causing an autoinflammatory syndrome. Similarly, patients with high-penetrance heterozygous mutations in the gene encoding A20 (haploinsufficiency of A20 (HA20)) display excessive ubiquitination and increased activity of NF-κB and of NLRP3 inflammasome activation. HA20 patients present with Behçet-like characteristics or an autoimmune lymphoproliferative syndrome (ALPS)-like phenotype, indicating diverse protein functions.Summary
This review summarizes recent discoveries in the field of NF-kB-related autoinflammatory diseases (relopathies) within the past 3 years and points to several questions that still remain unanswered.144.
145.
Cassandra D. Belair Thomas R. Yeager Patricia M. Lopez Catherine A. Reznikoff 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(25):13677-13682
Telomerase activity is readily detected in most cancer biopsies, but not in premalignant lesions or in normal tissue samples with a few exceptions that include germ cells and hemopoietic stem cells. Telomerase activity may, therefore, be a useful biomarker for diagnosis of malignancies and a target for inactivation in chemotherapy or gene therapy. These observations have led to the hypothesis that activation of telomerase may be an important step in tumorigenesis. To test this hypothesis, we studied telomerase activity in isogeneic samples of uncultured and cultured specimens of normal human uroepithelial cells (HUCs) and in uncultured and cultured biopsies of superficial and myoinvasive transitional cell carcinoma (TCC) of the bladder. Our results demonstrated that four of four TCC biopsies, representing both superficial and myoinvasive TCCs, were positive for telomerase activity, but all samples of uncultured HUC were telomerase negative. However, when the same normal HUC samples were established as proliferating cultures in vitro, telomerase activity was readily detected but usually at lower levels than in TCCs. Consistent with the above observation of the telomerase activity in HUCs, telomeres did not shorten during the HUC in vitro lifespan. Demonstration of telomerase in proliferating human epithelial cells in vitro was not restricted to HUCs, because it was also present in prostate and mammary cell cultures. Notably, telomerase activity was relatively low or undetectable in nonproliferating HUC cultures. These data do not support a model in which telomerase is inactive in normal cells and activated during tumorigenic transformation. Rather, these data support a model in which the detection of telomerase in TCC biopsies, but not uncultured HUC samples, reflects differences in proliferation between tumor and normal cells in vivo. 相似文献
146.
Cassandra A. Stanton Alyson B. Moadel Ryung S. Kim Andrea H. Weinberger 《AIDS care》2015,27(2):268-272
Loneliness is common in persons living with HIV (PLWH). Lonely people smoke at higher rates than the general population, and loneliness is a likely contributor to the ongoing smoking epidemic among PLWH. We explored factors associated with loneliness in a cohort of 272 PLWH smokers enrolled in two separate tobacco treatment trials. Loneliness was independently associated with lack of a spouse or partner, lower educational attainment, “other or unknown” HIV exposure category, depression, anxiety, recent alcohol consumption, and higher daily cigarette consumption. Referral to group therapy reduced loneliness, whereas referral to an individual web-based tobacco treatment did not. 相似文献
147.
148.
Taylor Enochs Anne E. Hill Cassandra E. Worley Crisnicaw Veríssimo Daranee Tantbirojn Antheunis Versluis 《Dental materials》2018,34(1):152-160
Objective
The relationship between post-gel shrinkage, total shrinkage, and cuspal flexure was examined. Cuspal flexure was measured on restored typodont teeth, which offered a standardized tooth shape for comparison of shrinkage stress effects among restorative composites.Methods
Six restorative composites were compared (Filtek LS, Venus Flowable, Tetric EvoCeram, Filtek Flowable, Esthet-X, and Filtek Supreme). Total shrinkage was determined from changes in projected surface area before and after polymerization (n = 10). Post-gel shrinkage was determined with a biaxial strain gauge that measured strain development during polymerization (n = 10). Cuspal flexure was determined using typodont maxillary second premolars with standard MOD slot preparation (n = 10). Flexure was determined by comparing the three-dimensionally scanned cuspal surfaces before and after restoration. Restoration bonding to the typodont cavity was achieved by sandblasting and adhesive application. Bond integrity was verified by measuring dye penetration. Results were analyzed using ANOVA and Student–Newman–Keuls post hoc test (significance level 0.05). Pearson was used for correlations.Results
Total and post-gel shrinkage were significant different for all composites (t-test; P < 0.001). Depending on the composite, only 9–41% of the total shrinkage was recorded as post-gel shrinkage. Bond integrity of restored typodont teeth was 96–99%. Cuspal flexure correlated strongly with post-gel shrinkage, but there was no correlation with total shrinkage.Significance
Cuspal flexure of restored typodont teeth showed the effect of shrinkage stress caused by polymerizing composite restorations, ensuring standardization while maintaining the effects of tooth/cavity geometry. Post-gel shrinkage gave a good indication to screen composites for the stress they may generate; total shrinkage had no direct correlation with stress. 相似文献149.
150.
Montaniel KR Billaud M Graham C Kim SK Carlson M Zeng W Zeng O Pan W Isakson BE Hall JL Adhikari N 《Journal of cardiovascular translational research》2012,5(3):274-279
Heparan sulfate proteoglycans are abundant matrix and membrane molecules. Smooth muscle specific deletion of one heparan sulfate biosynthetic enzyme, N-deacetylase-N-sulfotransferase1 leads to decreased vascular smooth muscle cell proliferation, and vascular wall thickness. We hypothesized that this may lead to changes in blood pressure in conscious mice. Blood pressure was measured via telemetry in SM22αCre(+)Ndst1(-/-)(n = 4) and wild type (n = 8) mice. Aorta and thoracodorsal artery luminal area is significantly smaller in SM22αCre(+)Ndst1(-/-) (n = 4-8, P = 0.02, P = 0.0002) compared to wild type (n = 7) mice. Diurnal differences were observed in both cohorts for systolic, diastolic, mean arterial blood pressure, and heart rate (P < 0.001 from T test). No significant differences were found in the above parameters between the cohorts in either light or dark times using a linear mixed model. In conclusion, deletion of N-deacetylase-N-sulfotransferase1 in smooth muscle did not influence any of the blood pressure parameters measured despite significant decrease in aorta and thoracodorsal artery luminal area. 相似文献