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91.
Weisleder N Soumaka E Abbasi S Taegtmeyer H Capetanaki Y 《Journal of molecular and cellular cardiology》2004,36(1):121-128
Mice deficient in desmin, the muscle-specific member of the intermediate filament gene family, display defects in all muscle types and particularly in the myocardium. Desmin null hearts develop cardiomyocyte hypertrophy and dilated cardiomyopathy (DCM) characterized by extensive myocyte cell death, calcific fibrosis and multiple ultrastructural defects. Several lines of evidence suggest impaired vascular function in desmin null animals. To determine whether altered capillary function or an intrinsic cardiomyocyte defect is responsible for desmin null DCM, transgenic mice were generated to rescue desmin expression specifically to cardiomyocytes. Desmin rescue mice display a wild-type cardiac phenotype with no fibrosis or calcification in the myocardium and normalization of coronary flow. Cardiomyocyte ultrastructure is also restored to normal. Markers of hypertrophy upregulated in desmin null hearts return to wild-type levels in desmin rescue mice. Working hearts were perfused to assess coronary flow and cardiac power. Restoration of a wild-type cardiac phenotype in a desmin null background by expression of desmin specifically within cardiomyocyte indicates that defects in the desmin null heart are due to an intrinsic cardiomyocytes defect rather than compromised coronary circulation. 相似文献
92.
Lancaster JM Powell CB Kauff ND Cass I Chen LM Lu KH Mutch DG Berchuck A Karlan BY Herzog TJ;Society of Gynecologic Oncologists Education Committee 《Gynecologic oncology》2007,107(2):159-162
Women with germline mutations in the cancer susceptibility genes, BRCA1 or BRCA2, associated with Hereditary Breast/Ovarian Cancer syndrome, have up to an 85% lifetime risk of breast cancer and up to a 46% lifetime risk ovarian cancer. Similarly, women with mutations in the DNA mismatch repair genes, MLH1, MSH2 or MSH6, associated with the Lynch/Hereditary Non-Polyposis Colorectal Cancer (HNPCC) syndrome, have up to a 40-60% lifetime risk of both endometrial and colorectal cancer as well as a 9-12% lifetime risk of ovarian cancer. Genetic risk assessment enables physicians to provide individualized evaluation of the likelihood of having one of these gynecologic cancer predisposition syndromes, as well the opportunity to provide tailored screening and prevention strategies such as surveillance, chemoprevention, and prophylactic surgery that may reduce the morbidity and mortality associated with these syndromes. Hereditary cancer risk assessment is a process that includes assessment of risk, education and counseling conducted by a provider with expertise in cancer genetics, and may include genetic testing after appropriate consent is obtained. This commentary provides guidance on identification of patients who may benefit from hereditary cancer risk assessment for Hereditary Breast/Ovarian Cancer and the Lynch/Hereditary Non-Polyposis Colorectal Cancer syndrome. 相似文献
93.
Ahmed Noah Badr Marwa M. El-Attar Hatem S. Ali Manal F. Elkhadragy Hany M. Yehia Amr Farouk 《Toxins》2022,14(2)
Spent coffee grounds (SCGs), which constitute 75% of original coffee beans, represent an integral part of sustainability. Contamination by toxigenic fungi and their mycotoxins is a hazard that threatens food production. This investigation aimed to examine SCGs extract as antimycotic and anti-ochratoxigenic material. The SCGs were extracted in an eco-friendly way using isopropanol. Bioactive molecules of the extract were determined using the UPLC apparatus. The cytotoxicity on liver cancer cells (Hep-G2) showed moderate activity with selectivity compared with human healthy oral epithelial (OEC) cell lines but still lower than the positive control (Cisplatin). The antibacterial properties were examined against pathogenic strains, and the antifungal was examined against toxigenic fungi using two diffusion assays. Extract potency was investigated by two simulated models, a liquid medium and a food model. The results of the extract showed 15 phenolic acids and 8 flavonoids. Rosmarinic and syringic acids were the most abundant phenolic acids, while apigenin-7-glucoside, naringin, epicatechin, and catechin were the predominant flavonoids in the SCGs extract. The results reflected the degradation efficiency of the extract against the growth of Aspergillus strains. The SCGs recorded detoxification in liquid media for aflatoxins (AFs) and ochratoxin A (OCA). The incubation time of the extract within dough spiked with OCA was affected up to 2 h, where cooking was not affected. Therefore, SCGs in food products could be applied to reduce the mycotoxin contamination of raw materials to the acceptable regulated limits. 相似文献
94.
D’Amico Randy S. Khatri Deepak Reichman Noah Patel Nitesh V. Wong Tamika Fralin Sherese R. Li Mona Ellis Jason A. Ortiz Rafael Langer David J. Boockvar John A. 《Journal of neuro-oncology》2020,147(2):261-278
Journal of Neuro-Oncology - Intra-arterial (IA) delivery of therapeutic agents across the blood-brain barrier (BBB) is an evolving strategy which enables the distribution of high concentration... 相似文献
95.
Hany Elmariah Yvette L. Kasamon Marianna Zahurak Karen W. Macfarlane Noah Tucker Gary L. Rosner Javier Bolaños-Meade Ephraim J. Fuchs Nina Wagner-Johnston Lode J. Swinnen Carol Ann Huff William H. Matsui Douglas E. Gladstone Shannon R. McCurdy Ivan Borrello Christian B. Gocke Satish Shanbhag Kenneth R. Cooke Richard F. Ambinder 《Biology of blood and marrow transplantation》2018,24(5):1099-1102
Outcomes of nonmyeloablative (NMA) haploidentical (haplo) blood or marrow transplant (BMT) with post-transplantation cyclophosphamide (PTCy) using non–first-degree relatives are unknown. We evaluated 33 consecutive adult patients (median age, 56 years) with hematologic malignancies who underwent NMA haplo T cell–replete BMT with PTCy at Johns Hopkins using second- or third-degree related donors. Donors consisted of 10 nieces (30%), 9 nephews (27%), 7 first cousins (21%), 5 grandchildren (15%), and 2 uncles (6%). Thirty-one patients (94%) reached full donor chimerism by day 60. The estimated cumulative incidence (CuI) of grades II to IV acute graft-versus-host disease (aGVHD) at day 180 was 24% (90% confidence interval [CI], 9% to 38%). Only 1 patient experienced grades III to IV aGVHD. At 1 year the CuI of chronic GVHD was 10% (90% CI, 0% to 21%). The CuI of nonrelapse mortality at 1 year was 5% (90% CI, 0% to 14%). At 1 year the probability of relapse was 31% (90% CI, 12% to 49%), progression-free survival 64% (90% CI, 48% to 86%), and overall survival 95% (90% CI, 87% to 100%). The 1-year probability of GVHD-free, relapse-free survival was 57% (90% CI, 41% to 79%). NMA haplo BMT with PTCy from non–first-degree relatives is an acceptably safe and effective alternative donor platform, with results similar to those seen with first-degree relatives. 相似文献
96.
F Klein C Gaebler H Mouquet DN Sather C Lehmann JF Scheid Z Kraft Y Liu J Pietzsch A Hurley P Poignard T Feizi L Morris BD Walker G Fätkenheuer MS Seaman L Stamatatos MC Nussenzweig 《The Journal of experimental medicine》2012,209(8):1469-1479
Two to three years after infection, a fraction of HIV-1-infected individuals develop serologic activity that neutralizes most viral isolates. Broadly neutralizing antibodies that recognize the HIV-1 envelope protein have been isolated from these patients by single-cell sorting and by neutralization screens. Here, we report a new method for anti-HIV-1 antibody isolation based on capturing single B cells that recognize the HIV-1 envelope protein expressed on the surface of transfected cells. Although far less efficient than soluble protein baits, the cell-based capture method identified antibodies that bind to a new broadly neutralizing epitope in the vicinity of the V3 loop and the CD4-induced site (CD4i). The new epitope is expressed on the cell surface form of the HIV-1 spike, but not on soluble forms of the same envelope protein. Moreover, the new antibodies complement the neutralization spectrum of potent broadly neutralizing anti-CD4 binding site (CD4bs) antibodies obtained from the same individual. Thus, combinations of potent broadly neutralizing antibodies with complementary activity can account for the breadth and potency of naturally arising anti-HIV-1 serologic activity. Therefore, vaccines aimed at eliciting anti-HIV-1 serologic breadth and potency should not be limited to single epitopes. 相似文献
97.
Background: First-year college students appear to be at particular risk for experiencing negative alcohol-related consequences. This risk has fostered a need to identify malleable factors associated with first-year student alcohol consumption. Studies have shown significant positive associations between perceived parental approval of drinking and alcohol use and associated consequences. However, researchers have not yet identified the exact mechanism responsible for this relationship.Objectives: This study examined a potential vehicle by which parents may communicate approval of drinking to their college aged children. Specifically, we tested if less parent communication about alcohol use would be perceived as tacit approval on the part of first-year college students.Methods: Two hundred seventy-nine first-year undergraduate students age 18–20 answered online surveys of perceived parental approval of drinking, negative alcohol-related consequences, perceived parental knowledge, and parent–student communication regarding alcohol use.Results: Contrary to hypothesis, our findings indicate the amount of parent–student communication regarding alcohol use did not predict perceived parental approval of drinking in first-year students, after controlling for the influence of gender, perceived parental knowledge, and negative consequences of alcohol use.Conclusions: Results suggest that first-year college students may not interpret less parent–student communication regarding alcohol as tacit approval of drinking. 相似文献
98.
99.
Min Chen Daniel T. Ohm Jeffrey S. Phillips Corey T. McMillan Noah Capp Claire Peterson Emily Xie David A. Wolk John Q. Trojanowski Edward B. Lee James Gee Murray Grossman David J. Irwin 《The Journal of neuroscience》2022,42(18):3868
Network analyses inform complex systems such as human brain connectivity, but this approach is seldom applied to gold-standard histopathology. Here, we use two complimentary computational approaches to model microscopic progression of the main subtypes of tauopathy versus TDP-43 proteinopathy in the human brain. Digital histopathology measures were obtained in up to 13 gray matter (GM) and adjacent white matter (WM) cortical brain regions sampled from 53 tauopathy and 66 TDP-43 proteinopathy autopsy patients. First, we constructed a weighted non-directed graph for each group, where nodes are defined as GM and WM regions sampled and edges in the graph are weighted using the group-level Pearson''s correlation coefficient for each pairwise node comparison. Additionally, we performed mediation analyses to test mediation effects of WM pathology between anterior frontotemporal and posterior parietal GM nodes. We find greater correlation (i.e., edges) between GM and WM node pairs in tauopathies compared with TDP-43 proteinopathies. Moreover, WM pathology strongly correlated with a graph metric of pathology spread (i.e., node-strength) in tauopathies (r = 0.60, p < 0.03) but not in TDP-43 proteinopathies (r = 0.03, p = 0.9). Finally, we found mediation effects for WM pathology on the association between anterior and posterior GM pathology in FTLD-Tau but not in FTLD-TDP. These data suggest distinct tau and TDP-43 proteinopathies may have divergent patterns of cellular propagation in GM and WM. More specifically, axonal spread may be more influential in FTLD-Tau progression. Network analyses of digital histopathological measurements can inform models of disease progression of cellular degeneration in the human brain.SIGNIFICANCE STATEMENT In this study, we uniquely perform two complimentary computational approaches to model and contrast microscopic disease progression between common frontotemporal lobar degeneration (FTLD) proteinopathy subtypes with similar clinical syndromes during life. Our models suggest white matter (WM) pathology influences cortical spread of disease in tauopathies that is less evident in TDP-43 proteinopathies. These data support the hypothesis that there are neuropathologic signatures of cellular degeneration within neurocognitive networks for specific protienopathies. These distinctive patterns of cellular pathology can guide future efforts to develop tissue-sensitive imaging and biological markers with diagnostic and prognostic utility for FTLD. Moreover, our novel computational approach can be used in future work to model various neurodegenerative disorders with mixed proteinopathy within the human brain connectome. 相似文献
100.
Joseph Driver Samantha E Hoffman Sherwin Tavakol Eleanor Woodward Eduardo A Maury Varun Bhave Noah F Greenwald Farshad Nassiri Kenneth Aldape Gelareh Zadeh Abrar Choudhury Harish N Vasudevan Stephen T Magill David R Raleigh Malak Abedalthagafi Ayal A Aizer Brian M Alexander Keith L Ligon David A Reardon Patrick Y Wen Ossama Al-Mefty Azra H Ligon Adrian M Dubuc Rameen Beroukhim Elizabeth B Claus Ian F Dunn Sandro Santagata Wenya Linda Bi 《Neuro-oncology》2022,24(5):796
BackgroundMeningiomas are the most common primary intracranial tumor in adults. Clinical care is currently guided by the World Health Organization (WHO) grade assigned to meningiomas, a 3-tiered grading system based on histopathology features, as well as extent of surgical resection. Clinical behavior, however, often fails to conform to the WHO grade. Additional prognostic information is needed to optimize patient management.MethodsWe evaluated whether chromosomal copy-number data improved prediction of time-to-recurrence for patients with meningioma who were treated with surgery, relative to the WHO schema. The models were developed using Cox proportional hazards, random survival forest, and gradient boosting in a discovery cohort of 527 meningioma patients and validated in 2 independent cohorts of 172 meningioma patients characterized by orthogonal genomic platforms.ResultsWe developed a 3-tiered grading scheme (Integrated Grades 1-3), which incorporated mitotic count and loss of chromosome 1p, 3p, 4, 6, 10, 14q, 18, 19, or CDKN2A. 32% of meningiomas reclassified to either a lower-risk or higher-risk Integrated Grade compared to their assigned WHO grade. The Integrated Grade more accurately identified meningioma patients at risk for recurrence, relative to the WHO grade, as determined by time-dependent area under the curve, average precision, and the Brier score.ConclusionWe propose a molecularly integrated grading scheme for meningiomas that significantly improves upon the current WHO grading system in prediction of progression-free survival. This framework can be broadly adopted by clinicians with relative ease using widely available genomic technologies and presents an advance in the care of meningioma patients. 相似文献