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111.
Lucio Díaz-Flores Ricardo Gutirrez Miriam Gonzlez-Gmez Maria Pino García Lucio Díaz-Flores Jr. Jos Luís Carrasco Pablo Martín-Vasallo 《International journal of molecular sciences》2021,22(7)
Several origins have been proposed for cancer-associated fibroblasts (CAFs), including resident CD34+ stromal cells/telocytes (CD34+SCs/TCs). The characteristics and arrangement of mammary CD34+SCs/TCs are well known and invasive lobular carcinoma of the breast (ILC) is one of the few malignant epithelial tumours with stromal cells that can express CD34 or αSMA, which could facilitate tracking these cells. Our objective is to assess whether tissue-resident CD34+SCs/TCs participate in the origin of CAFs in ILCs. For this purpose, using conventional and immunohistochemical procedures, we studied stromal cells in ILCs (n:42) and in normal breasts (n:6, also using electron microscopy). The results showed (a) the presence of anti-CD34+ or anti-αSMA+ stromal cells in varying proportion (from very rare in one of the markers to balanced) around nests/strands of neoplastic cells, (b) a similar arrangement and location of stromal cells in ILC to CD34+SCs/TCs in the normal breast, (c) both types of stromal cells coinciding around the same nest of neoplastic cells and (d) the coexpression of CD34 and αSMA in stromal cells in ILC. In conclusion, our findings support the hypothesis that resident CD34+SCs/TCs participate as an important source of CAFs in ILC. Further studies are required in this regard in other tumours. 相似文献
112.
Ahmed Abdelaal Ahmed Mahmoud M. Alkhatip Michail Georgakis Lucio R. Montero Valenzuela Mohamed Hamza Ehab Farag Jaqui Hodgkinson Hisham Hosny Ahmed M. Kamal Mohamed Wagih Amr Naguib Hany Yassin Haytham Algameel Mohamed Elayashy Mohamed Abdelhaq Mohamed I. Younis Hassan Mohamed Mohammed Abdulshafi Mohamed A. Elramely 《International journal of molecular sciences》2021,22(6)
SARS-CoV-2 currently lacks effective first-line drug treatment. We present promising data from in silico docking studies of new Methisazone compounds (modified with calcium, Ca; iron, Fe; magnesium, Mg; manganese, Mn; or zinc, Zn) designed to bind more strongly to key proteins involved in replication of SARS-CoV-2. In this in silico molecular docking study, we investigated the inhibiting role of Methisazone and the modified drugs against SARS-CoV-2 proteins: ribonucleic acid (RNA)-dependent RNA polymerase (RdRp), spike protein, papain-like protease (PlPr), and main protease (MPro). We found that the highest binding interactions were found with the spike protein (6VYB), with the highest overall binding being observed with Mn-bound Methisazone at −8.3 kcal/mol, followed by Zn and Ca at −8.0 kcal/mol, and Fe and Mg at −7.9 kcal/mol. We also found that the metal-modified Methisazone had higher affinity for PlPr and MPro. In addition, we identified multiple binding pockets that could be singly or multiply occupied on all proteins tested. The best binding energy was with Mn–Methisazone versus spike protein, and the largest cumulative increases in binding energies were found with PlPr. We suggest that further studies are warranted to identify whether these compounds may be effective for treatment and/or prophylaxis. 相似文献
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A nonlinear design procedure for microwave power amplifiers is presented. The methodology makes use of a complete nonlinear model for the active device and an exact nonlinear analysis method. Suitable harmonic loading conditions for efficient power performance are imposed simultaneously and consistently with the analysis. The procedure is much faster than conventional repeated nonlinear analyses. © 1995 John Wiley & Sons, Inc. 相似文献
117.
We established a novel animal model for rheumatoid arthritis (RA) by following backcrossing to DBA/1 of (SWR/J x DBA/1)F1 TCR-beta Tg mice, previously reported to be highly susceptible to collagen-induced arthritis. These mice evolved, upon collagen type II immunization, into a chronic arthritis that histopathologically resembles RA. The availability of such a model prompted us to study the role of CD4+ T cells throughout the evolution of disease. Here, we show that administration of nondepleting anti-CD4 not only prevented the evolution of disease but also treated established arthritis. Moreover, functional analyses of T cells isolated from anti-CD4-treated mice demonstrated that the mechanism of protection is not achieved by suppression of the Th1 population but is mediated by induction of collagen type II-specific T cell anergy. Our study suggests that: 1) CD4+ T cells have a fundamental role both in the induction and in the perpetuation of disease; 2) targeting T cells may be an appropriate therapeutic option; and 3) a suitable and well-balanced anti-CD4 treatment may be a valid approach to the control of RA. 相似文献
118.
Positive and negative rates of change of attenuation are studied jointly with the in-between fade duration using Sirio 11.6 GHz beacon four-year data for several attenuation thresholds, collected in northern Italy. The letter shows that the rate conditional distributions are log-normal, and that little correlation exists between negative and positive rates and durations. 相似文献
119.
Many researchers install Campbell-Stokes sunshine recorders to evaluate the global irradiation from heliophany measurements using the well-known Ångström linear regression. Because of the statistical nature of this relation, the actual solar irradiation values are determined with some given standard deviation, the fluctuation of which a poor empirical solar radiation database can contribute to. In this paper a procedure (“cross-validation”) has been devised, based on 8 years of daily sunshine and daily global solar radiation data, in order to investigate the dependence of the general standard deviation on the size of the database. Therefore one can infer that a database of at least 14 years is necessary and may be sufficient not only to obtain, by Ångström regression, a trustworthy and statistically stable estimation of the daily global solar irradiation but, further, to set up a “theoretical” and statistically stable distribution of any climatic quantity. Beyond this limit, the variability of the climatological quantities originates from only their intrinsic statistical nature, independently of the size of the database used 相似文献
120.
R Dezi S Niveloni E Sugai S Pedreira E Smecuol H Vazquez I Doldan A Cabanne L Boerr J Valero Z Kogan E Mauri?o JC Bai 《Canadian Metallurgical Quarterly》1997,92(8):1326-1330
BACKGROUND/AIMS: Rectal gluten challenge is a simple, sensitive, and specific test of mucosal gluten sensitivity. Our aims in this study were to evaluate gluten sensitivity in a group of relatives of celiac patients and to compare these findings with those obtained on small bowel histology, celiac disease-related serology, and HLA typing. METHODS: A 4-h rectal gluten challenge was performed with 6 g of crude gluten in saline solution in 29 first-degree relatives, 20 well-diagnosed celiac patients, and 10 subjects in whom celiac disease had been excluded. The number of intraepithelial lymphocytes in pre- and postchallenge frozen rectal biopsies (pan T-cell immunocytochemistry) was quantified by computerized image analysis. RESULTS: The intraepithelial lymphocyte response after gluten instillation was significantly higher in celiac disease patients (median, 126% increase above the baseline count; 95% confidence interval: 61-213%) compared with control subjects (median, -5%; 95% confidence interval: -29-5%). Using a cut-off of 20% change in intraepithelial lymphocyte count, 14 relatives (48%) showed a celiac-like response. Two of these subjects had partial villous atrophy and increased lymphocyte counts in the small bowel mucosa. One of them also exhibited a positive celiac disease-related serology and the typical celiac human lymphocyte antibody (HLA) DQ2. The remaining 12, and all those relatives with a negative challenge, had normal small bowel mucosa and were negative for antigliadin and endomysial antibodies. The characteristic celiac HLA (DQA1 0501 DQB1 0201 heterodimer) was identified in five relatives with positive challenge (including the patient with more severe mucosal atrophy) but was also present in eight relatives with no evidence of gluten sensitivity in the rectal mucosa. CONCLUSIONS: Our study characterizes a subgroup of relatives of celiac patients who show mucosal evidence of sensitization after local instillation of gluten in the rectum but who have no other features of celiac disease. 相似文献