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131.
132.
Aaron M. Rohr William T. Kuo 《Journal of vascular and interventional radiology : JVIR》2019,30(10):1682-1685.e1
133.
Emma Jones Xiao Lin Zhu L. Ralph Rohr Robert A. Stephenson Arthur R. Brothman 《Genes, chromosomes & cancer》1994,11(3):163-170
Twenty prostate tumor specimens, obtained from radical prostatectomies, and two lymph node metastases were examined by classical and molecular cytogenetic methods. A sample from each tumor was analyzed histologically and used for touch preparations. Adjacent samples were used for preparation of single-cell suspensions before cell culture (DirFISH) and for establishing cell cultures, which were subsequently harvested for classical G-banding analysis. Fluorescence in situ hybridization (FISH) was performed on touch preparations, DirFISH, and cells obtained from tissue culture. Biotinylated pericentromeric probes for chromosomes 7 and 17, in addition to a digoxigenin-labeled X-chromosome probe, were used in a dual-color FISH assay. The results indicated that, in uncultured tumor cells, chromosome 17 was lost in 55% of specimens, chromosome 7 was gained in 16% of specimens, and 9% of specimens showed large tetraploid populations. After cell culture, 23% of specimens showed loss of chromosome 17, no specimens showed gain of chromosome 7, and no tetraploid populations were present. This study suggests that loss of chromosome 17 may play an important role in the development of prostate cancer, and that genetic changes observed after selection in vitro may not represent those in the original tumor. 相似文献
134.
Ph. de Moerloose M. Jeannet B. Martins-da-Silva Ch. Werner-Favre J. Rohr G. Gauthier 《Tissue antigens》1979,13(5):357-360
Previous studies of multiple sclerosis patients showed the existence of a positive association between multiple sclerosis and HLA--A3 and --B7, as well as a negative association with B12. These observations have been confirmed. In addition, a more marked association has been observed with two recently identified B-cell antigens, DRw2 and DRw3, closely related to the HLA--D locus. The presence of cold lymphocytotoxic antibodies was found to bear no relationship with those two specificities. These results suggest that two genes of the HLA--DR region may play a role in the pathogenesis of multiple sclerosis. 相似文献
135.
Hernia - To evaluate the usefulness and outcomes of hypnosis associated with local anesthesia during inguinal hernia repair procedure, notably on post-operative pain. A prospective study included... 相似文献
136.
Jason R. Rohr Christopher J. Salice Roger M. Nisbet 《Critical reviews in toxicology》2016,46(9):756-784
Ecological risk assessment (ERA) is the process used to evaluate the safety of manufactured chemicals to the environment. Here we review the pros and cons of ERA across levels of biological organization, including suborganismal (e.g., biomarkers), individual, population, community, ecosystem and landscapes levels. Our review revealed that level of biological organization is often related negatively with ease at assessing cause–effect relationships, ease of high-throughput screening of large numbers of chemicals (it is especially easier for suborganismal endpoints), and uncertainty of the ERA because low levels of biological organization tend to have a large distance between their measurement (what is quantified) and assessment endpoints (what is to be protected). In contrast, level of biological organization is often related positively with sensitivity to important negative and positive feedbacks and context dependencies within biological systems, and ease at capturing recovery from adverse contaminant effects. Some endpoints did not show obvious trends across levels of biological organization, such as the use of vertebrate animals in chemical testing and ease at screening large numbers of species, and other factors lacked sufficient data across levels of biological organization, such as repeatability, variability, cost per study and cost per species of effects assessment, the latter of which might be a more defensible way to compare costs of ERAs than cost per study. To compensate for weaknesses of ERA at any particular level of biological organization, we also review mathematical modeling approaches commonly used to extrapolate effects across levels of organization. Finally, we provide recommendations for next generation ERA, submitting that if there is an ideal level of biological organization to conduct ERA, it will only emerge if ERA is approached simultaneously from the bottom of biological organization up as well as from the top down, all while employing mathematical modeling approaches where possible to enhance ERA. Because top-down ERA is unconventional, we also offer some suggestions for how it might be implemented efficaciously. We hope this review helps researchers in the field of ERA fill key information gaps and helps risk assessors identify the best levels of biological organization to conduct ERAs with differing goals. 相似文献
137.
Dental and dental hygiene students frequently interact with patients with herpes simplex virus (HSV) infections, often simply referred to as cold sores. The objectives of this study were to assess dental and dental hygiene students' knowledge, attitudes, and professional behavior concerning the treatment of patients with HSV infections and to investigate the relationships among knowledge, attitudes, and professional behavior. Questionnaire data were collected from 337 dental and seventy-three dental hygiene students at regularly scheduled classes. Dental and dental hygiene students did not differ in their overall knowledge concerning HSV infections. Dental hygiene students were more apprehensive about treating patients with these infections, but used more appropriate professional behavior compared to dental students. Dental students' knowledge and appropriateness of professional behavior increased over the course of their education. Overall, it was found that an increase in student knowledge was associated with increased apprehension related to treating these patients. However, the more apprehensive they were, the more they engaged in appropriate professional behavior. Educating future health care providers about the treatment of patients with infectious and communicable diseases can potentially increase the students' apprehension/negative attitudes concerning providing care, while at the same time increasing appropriate professional behavior during their education. Addressing students' apprehensions might be a crucial moderator that will determine whether they will provide the best possible care for these patients in their future professional lives. 相似文献
138.
Melissa Vos Marija Dulovic-Mahlow Frida Mandik Lisa Frese Yuliia Kanana Sokhna Haissatou Diaw Julia Depperschmidt Claudia Bhm Jonas Rohr Thora Lohnau Inke R. Knig Christine Klein 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(43)
Energy production via the mitochondrial electron transport chain (ETC) and mitophagy are two important processes affected in Parkinson’s disease (PD). Interestingly, PINK1, mutations of which cause early-onset PD, plays a key role in both processes, suggesting that these two mechanisms are connected. However, the converging link of both pathways currently remains enigmatic. Recent findings demonstrated that lipid aggregation, along with defective mitochondria, is present in postmortem brains of PD patients. In addition, an increasing body of evidence shows that sphingolipids, including ceramide, are altered in PD, supporting the importance of lipids in the pathophysiology of PD. Here, we identified ceramide to play a crucial role in PINK1-related PD that was previously linked almost exclusively to mitochondrial dysfunction. We found ceramide to accumulate in mitochondria and to negatively affect mitochondrial function, most notably the ETC. Lowering ceramide levels improved mitochondrial phenotypes in pink1-mutant flies and PINK1-deficient patient-derived fibroblasts, showing that the effects of ceramide are evolutionarily conserved. In addition, ceramide accumulation provoked ceramide-induced mitophagy upon PINK1 deficiency. As a result of the ceramide accumulation, β-oxidation in PINK1 mutants was decreased, which was rescued by lowering ceramide levels. Furthermore, stimulation of β-oxidation was sufficient to rescue PINK1-deficient phenotypes. In conclusion, we discovered a cellular mechanism resulting from PD-causing loss of PINK1 and found a protective role of β-oxidation in ETC dysfunction, thus linking lipids and mitochondria in the pathophysiology of PINK1-related PD. Furthermore, our data nominate β-oxidation and ceramide as therapeutic targets for PD.Loss of PINK1 function causes autosomal recessive early-onset Parkinson’s disease (PD). Most patients present with bradykinesia, rigidity, resting tremor, and dyskinesia and are responsive to dopamine replacement therapy (1). On the cellular level, PINK1 disease mutations result in impaired energy metabolism and a variety of mitochondrial defects that can partially be alleviated by stimulation of energy metabolism (2–4). Intriguingly, abnormal mitochondrial morphology, along with lipid aggregates, was recently discovered to be present in Lewy bodies of postmortem PD patients’ brains (5), challenging the previously held notion of alpha-synuclein being the almost exclusive neuropathological correlate. This finding confirms the involvement of mitochondrial dysfunction in PD and additionally suggests a critical role of lipids in the pathogenesis of PD.PINK1 is important for the phosphorylation of the Complex I subunit NdufA10 resulting in efficient Complex I and electron transport chain (ETC) activity (6, 7). This function is evolutionarily conserved between Drosophila and humans. Hence, in both flies and humans, loss of PINK1 results in an impaired ETC, reduced ATP levels, and defective mitochondrial morphology (6, 8, 9), all of which are ubiquitously observed in the fly already at the early larval stage. Furthermore, alongside Parkin, PINK1 plays a crucial role in mitophagy to remove defective mitochondria that appears to be defective in an age-dependent fashion (10–13). Pink1-mutant Drosophila melanogaster additionally show thorax muscle degeneration and defective flying ability (8, 9). These latter defects, together with impaired mitochondrial morphology, can be rescued by expressing the fission-promoting protein Drp1 (14). However, increased fission does not improve ETC-related defects (15). Furthermore, stimulation or facilitation of the ETC rescues ETC-related phenotypes in pink1-mutant Drosophila, including ATP levels and mitochondrial morphology (3, 4, 7, 15, 16). These data collectively suggest two parallel mechanisms that converge on a shared common pathway leading to the development of PD. However, the link between these two pathways has yet to be resolved.Recently, disrupted lipid homeostasis has garnered increasing attention in PD (16–18). Furthermore, ceramide, the basic sphingolipid, is altered in several PD models and has been implicated in PD-related alpha-synuclein toxicity (17–20). Interestingly, ceramide induces mitophagy that is facilitated by Drp1 (21). Furthermore, pathogenic variants in Glucocerebrosidase (GCase), an enzyme involved in ceramide synthesis, are known to be the most common risk factor for PD (22, 23). However, the exact mechanism remains enigmatic. We found increased ceramide levels in isolated mitochondria of Pink1−/− knockout (KO) mouse embryonic fibroblasts (MEFs) (16) and Pink1-deficient flies. Increased ceramide levels are detrimental for proper ETC function (24). Hence, we hypothesize that ceramide accumulation in PINK1 deficiency affects ETC function and mitophagy and constitutes the missing link between these two important processes affected in PD. 相似文献
139.
Jan Rohr Ulrich Pannicke Michaela Döring Annette Schmitt-Graeff Elisabeth Wiech Andreas Busch Carsten Speckmann Ingo Müller Peter Lang Rupert Handgretinger Paul Fisch Klaus Schwarz Stephan Ehl 《Journal of clinical immunology》2010,30(2):314-320
Introduction
We describe a girl presenting at age 6 years with a history of chronic ulcerating intestinal inflammation since 9 months of age. She exhibited a severe, steroid-dependent clinical course of intestinal inflammation over several years in the absence of serious infections.Results and Discussion
Immunodeficiency was first considered at 6 years of age due to chronic lymphopenia. Immunophenotyping revealed low B and T cell counts with few naïve T cells, a skewed TCR repertoire, and TCR γ/δ T cell predominance, suggesting a defect of lymphocyte development. Genetic and functional analyses identified a hypomorphic mutation in the DCLRE1C (ARTEMIS) gene compromising V(D)J recombination efficiency, but allowing residual T and B cell development. Hematopoetic stem cell transplantation reconstituted the lymphocyte compartment and cured the inflammatory bowel disease.Conclusion
This report illustrates that a genetic disorder of lymphocyte development can present with chronic inflammatory bowel disease as the dominant phenotype in the absence of severe infection susceptibility. 相似文献140.
Sandra S. Rohr Luís Arthur Flores Pelloso Aline dos Santos Borgo Jo?o Garibaldi de Rezende Jr. Maria Regina Regis Silva Mihoko Yamamoto Maria de Lourdes L. F. Chauffaille 《Medical oncology (Northwood, London, England)》2012,29(5):3570-3573
Transformation of myelodysplastic syndrome (MDS) into acute myelogenous leukemia occurs in approximately 30?% of cases, while progression into acute lymphoblastic leukemia (ALL) is rare. We report on a 67-year-old man with the diagnosis of MDS, subtype refractory anemia with ring sideroblasts (RARS), karyotype 20q-?, JAK-2 negative and grade III fibrosis on the bone marrow biopsy, who evolved into ALL 33?months after the diagnosis of MDS. RARS is one of the subtypes of MDS with most indolent course. Deletion of the long arm of chromosome 20 (20q-) is considered as good prognosis by the International Prognostic Scoring System, an important scoring system for predicting survival and evolution of MDS. Primary MDS with bone marrow fibrosis may represent a distinct clinicopathological and is supposed to have an unfavorable prognosis. The combined analysis of these features makes this rare report still more challenging and illustrates that biology of MDS is yet to be discovered. 相似文献