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Notes on Quantitative Structure-Properties Relationships （QSPR） Part Four： Quantum Multimolecular Polyhedra, Collective Vectors, Quantum Similarity, and Quantum QSPR Fundamental Equation

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Management Studies 2016年第1期4卷 33-47页

作者： Ramon Carbo-Dorca silvia gonzalez Universitat de Girona Girona Catalonia Spain Universidad Tecnica Particular de Loja Loja Ecuador

The nature and origin of a fundamental quantum QSPR （QQSPR） equation are discussed. In principle, as any molecular structure can be associated to quantum mechanical density functions （DF）, a molecular set can be reconstructed as a quantum multimolecular polyhedron （QMP）, whose vertices are formed by each molecular DF. According to QQSPR theory, complicated kinds of molecular properties, like biological activity or toxicity, of molecular sets can be calculated via the quantum expectation value of an approximate Hermitian operator, which can be evaluated with the geometrical information contained in the attached QMP via quantum similarity matrices. Practical ways of solving the QQSPR problem from the point of view of QMP geometrical structure are provided. Such a development results into a powerful algorithm, which can be implemented within molecular design as an alternative to the current classical QSPR procedures.

Ventriculo-atrial shunt with occlusion of the internal jugular vein: operative experience and surgical technique

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中华神经外科杂志(英文) 2024年第2期10卷 1-8页

作者： Quintero silvia Tatiana Ramirez-Velandia Felipe Moreno Andres Felipe Hortua Vera Lina Rugeles Paula gonzalez Rafael Augusto Azuero Pontificia Universidad Javeriana Clinica Medilaser S.A.S. Clinica Chicamocha Bucaramanga Santander Colombia Neurology and Neurosurgery Research Group Pontificia Universidad Javeriana Bogotá D.C. Colombia Universidad Industrial de Santander Clinica Chicamocha Bucaramanga Colombia Universidad Autónoma de Bucaramanga Clinica Chicamocha Bucaramanga Colombia Clinica Chicamocha Bucaramanga Santander Colombia

Background Ventricular shunts are one of the most frequent techniques used for the management of hydrocephalus. The ventriculoperitoneal shunt (VPS) is the most commonly performed procedure, and the ventriculoatrial shunt (VAS) is the second option in most medical centers. The main objective of this study is to introduce and describe a surgical approach for VAS outlining our experience and comparing it with traditional shunting *** In this retrospective cohort comparison study, we included patients with hydrocephalus treated with a surgical procedure between January 2010 and February 2021 at a single academic institution. We categorized the procedures into two groups: patients with VPS and conventional VAS grouped together into the conventional technique (CT) group, and the second group was patients with whom we performed VAS with complete internal jugular vein occlusion (IJVOT). We compared the surgical time, postoperative complications, and occurrence of shunt failure among the groups by performing univariate analysis using the Fisher exact *** Out of the 106 patients included in the analysis, IJVOT was performed in 66 patients, and CT in 40 patients. The median surgical time was 60 min (IQR 60-90) for IJVOT versus 100 min (IQR 60-120) for CT (p < 0.01). In the follow-up a month after the procedure, 83.3% of patients with IJVOT and 62.5% of patients with CT did not require shunt removal or shunt revision (p < 0.01). Shunt revision rates were 12.5% and 1.5% for CT while 1.5% and 2.5% for IJVOT at 1 and 6 months after the *** Our findings demonstrate that VAS with IJVOT is a safe method that exhibited shorter surgical times and outcomes comparable to CT. However, since the present study represents the first cohort evaluating IJVOT, it is imperative to conduct larger prospective studies, along with clinical trials, to fully explore and establish efficacy, long-term outcomes, and an in-depth comparison among shunting techniques

关键词： Hydrocephalus Ventriculoatrial shunting Internal jugular vein Operative time Complications Shunt removal

Estimation of Contraction Coefficient of Gorlin Equation for Assessment of Aortic Valve Area in Aortic Stenosis

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World Journal of Cardiovascular Diseases 2017年第4期7卷 119-130页

作者： Ricardo A. Migliore María E. Adaniya Miguel Barranco Guillermo Miramont silvia gonzalez Horacio Tamagusuku Laboratory of Echocardiography Department of Cardiology Hospital Eva Perón San Martín Argentina

Background: The Gorlin equation is the reference method for the assessment of aortic valve area in aortic stenosis and is calculated using a constant, called the coefficient of contraction, which is empirically assumed to be 1. This coefficient is the ratio of effective aortic area to anatomic aortic area, and a value of 1 indicates that both are the same. The purpose of this study was to estimate the actual coefficient of contraction in patients with aortic stenosis and to evaluate its impact on aortic area as calculated by the Gorlin equation. Methods: We studied 17 patients with moderate to severe aortic stenosis. Effective aortic area was calculated using the continuity equation. Anatomic aortic area was obtained by planimetry with transesophageal echocardiography. Aortic valve area by the Gorlin equation was calculated from echocardiography data. The coefficient of contraction was derived as above. Results: The coefficient of contraction was inversely related to the pressure recovery. Effective area was correlated with anatomic area (r = 0.86, P 2). Aortic area by the Gorlin equation was not correlated with anatomic area, but the correlation became significant when the Gorlin equation was corrected for coefficient of contraction and pressure recovery. Conclusions: Using a coefficient of contraction of 1 in the Gorlin equation gives a poor correlation with anatomic area. Using the calculated coefficient of contraction for each patient and the mean gradient for pressure recovery improves the correlation with anatomic area. These facts could be taken in account when Gorlin equation is considered as the reference method.

关键词： Aortic Stenosis Echocardiography Hemodynamics Assessment

In vitro and in vivo trypanocidal action of aescin and aescin liposomes against Trypanosoma evansi in experimental mice

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Asian Pacific Journal of Tropical Biomedicine 2014年第12期4卷 947-951页

作者： Matheus Dellamea Baldissera Nathieli Bianchin Bottari Thirssa Helena Grando Roberto Christ Vianna Santos Ana Julia Figueiro Dalcin Patrfcia Gomes Renata Platcheck Raffin Carine Eloise Prestes Zimmerman Janio Morais Santurio silvia gonzalez Monteiro Aleksandro Schafer Da Silva Department of Microbiology and Parasitology Universidade Federal de Santa Maria(UFSM) Laboratory of Microbiology Centro Universitdrio Franciscano Laboratory of Nanotechnology Centro Universitdrio Franciscano Department of Animal Science Universidade do Estado de Santa Catarina(UDESC)

Objective:To verify the trypanocidal effectiveness of aescin and aescin liposomes against Trypanosoma evansi in vitro and in ***:Aescin and aescin liposomes were used in vitro on trypomastigotes at different concentrations(0.5%,1.0%and 2.0%) and exposure times(0,1,3,6 and 9 h).In vivo tests were performed using mice as the experimental *** evansi infected mice were treated with aescin and aescin liposomes with doses of 60 and 100 mg/kg during 4 ***:The three concentrations tested in free form and nanoencapsulated showed trypanocidal activity in vitro,completely eliminating the parasites in small concentration after6 h of *** treated with aescin(100 mg/kg) and aescin liposomes(100 mg/kg)showed increase in longevity,however without curative ***:Active compounds present in natural products,such as aescin,may potentiate the treatment of trypanosomosis when used in association with other trypanocidal drugs.

关键词： Surra Nanotechnology Aesculus hippocastanum Trypanosome

拉普拉塔河流域以及巴塔哥尼亚地区及相关海域水生态栖息地的改变

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AMBIO－人类环境杂志 2004年第1期33卷 67-75页

作者： Ana Cristina Mugetti Alberto Tomás Calcagno Carlos Alberto Brieva María silvia Giangiobbe Andrea Pagani silvia gonzalez 石秋池阿根廷水资源研究所 HIDRONOR(北巴塔哥尼亚水电局)董事会阿根廷国立Mar del Plata大学阿根廷国立Mar del Plata大学经济系布宜诺斯艾利斯大学

本文描述了南美大陆南部陆地和东南沿海地区环境特性及水生栖息地和群落的现状(GIWA巴塔哥尼亚大陆架亚区),结果来自一项GIWA项目框架任务所完成的一份全面评估,绝大部分依据的是公开发表的数据。分析主要集中在跨边界水资源目前的情况... 详细信息

本文描述了南美大陆南部陆地和东南沿海地区环境特性及水生栖息地和群落的现状(GIWA巴塔哥尼亚大陆架亚区),结果来自一项GIWA项目框架任务所完成的一份全面评估,绝大部分依据的是公开发表的数据。分析主要集中在跨边界水资源目前的情况和人类活动带来的影响。内陆水体的栖息地和群落变化主要是由为发电和其他用途而建的水坝和水库引起的。从活水环境到净水环境影响了生境,造成了生物群落的改变。在拉普拉塔(La Plata)河流域,外来入侵物种使本地物种消失。过度捕捞和污染影响了生物多样性,造成了海洋栖息地质量下降。本篇文章讨论了相关的原因,讨论了布宜诺斯艾利斯省和渔业资源由两国共享的阿根廷—乌拉圭公共渔业区对沿海生态环境的政策选择。

关键词：拉普拉塔河流域生态系统 GIWA 食物链环境保护

Altered Expression of Aromatase, Estrogen Receptors and Progesterone Receptors in Human Leydig Cell Hyperplasia

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Advances in Bioscience and Biotechnology 2015年第1期6卷 1-10页

作者： Candela Rocío González Pablo Ignacio Felipe Inserra Claudio Terradas Roberto Ponzio Elisa Puigdomenech Oscar Levalle Alfredo Daniel Vitullo Ricardo Saúl Calandra silvia Ines gonzalez-Calvar Research Center of Biomedical Biotechnology Environmental and Diagnostic Studies Maimónides University Buenos Aires Argentina División Endocrinología Hospital Durand Buenos Aires Argentina Facultad de Medicina Universidad de Buenos Aires Buenos Aires Argentina Instituto Medico PREFER Calle 995 No 2348 San Martin Argentina Laboratorio de Endocrinología Molecular de la Reproducción Instituto de Biología y Medicina Experimental (CONICET) Buenos Aires Argentina Laboratorio de Endocrinología Molecular de la Reproducción Instituto de Biología y Medicina Experimental (CONICET) Facultad de Medicina Universidad de Buenos Aires Buenos Aires Argentina

Testicular function is regulated by pituitary hormones and also by paracrine and autocrine factors. A number of reports have pointed out the importance of estrogens and progesterone in male reproductive tract. Recently, we have reported in testicular biopsies from men with Sertoli Cell Only Syndrome (SCO) or Hypospermatogenesis (H) with Leydig cell hyperplasia (LCH) an increase in the expression of the TGFB1 and its receptors ALK1 and endoglin, which are involved in the proliferation of Leydig cells. The aim of the present work was to analyze the expression of aromatase, estrogen and progesterone receptors (ERs, PR) in pathological testicular biopsies with SCO or H with and without LCH. The ERs and CYP19 proteins were detected in the Leydig cells from all pathological biopsies analyzed. Biopsies with SCO or H with LCH showed an increment in the immunostaining of CYP19 and ERs in the Leydig cells respect to biopsies without LCH. The gene expression of CYP19 was increased in SCO or H biopsies with LCH respect to SCO and H biopsies without LCH. PR was localized in Leydig cells and showed a significant increment in biopsies with LCH respect from biopsies without LCH. The gene expression of both PRA and PRB was increased in biopsies with LCH respect to biopsies without LCH. In concussion, alterations in the gene expression of aromatase, ERs, and PR and the likely interactions of these systems with locally produced factors such as growth factors and cytokines, might lead to Leydig cell proliferation in testicular pathology.

关键词： Aromatase Progesterone Estrogen Leydig

Preparation and characterization of phosphate-modified mesoporous TiO2 incorporated in a silica matrix and their photocatalytic properties in the photodegradation of Congo red

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Frontiers of Materials Science 2017年第3期11卷 250-261页

作者： Alberto ESTRELLA gonzalez Maximiliano ASOMOZA Ulises ARELLANO Sandra CIPAGAUTA DiAZ silvia SOLíS Department of Chemistry Metropolitan Autonomous University-lztapalapa P.O. Box 55-532 C.P. 09340 México City México

This study describes the development of mesostructured TiO2 photo- catalysts modified with PO4^3- to improve its specific surface area and reduce the recombination rate of the electron-hole pairs. The mesoporous photocatalyst was successfully incorporated into a high specific surface area silica matrix by the hydrolysis reaction of tetraethyl orthosilicate （TEOS）. Pluronic 123 and phosphoric acid were used as the directing agent for the structure of the mesoporous TiO2 and as a source of phosphorus, respectively, TiO2, P/TiO2, TiO2-SiO2 and P/TiO2-SiO2 materials were characterized by BET, XRD, TEM-EDS, FTIR and UV-vis DRS measurements. The photoactivity of TiO2-SiO2 nanocomposites containing 15 wt.% photocatalystJsilica was evaluated in the degradation reaction of anionic dyes with UV radiation. The proposed nanomaterials showed high potential for applications in the remediation of wastewater, being able to reuse in several cycles of reaction, maintaining its photoactivity and stability. The separation and recovery time of the material is reduced between cycles since no centrifugation or filtration processes are required after the photooxidation reaction.

关键词： photocatalysis phosphated TiO2 TiO2-SiO2 Congo red dye

Three-dimensional acoustic propagation model for shallow waters based on an indirect boundary element method

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Chinese Physics B 2023年第5期32卷 485-495页

作者： Edmundo F.Lavia Juan D.gonzalez silvia Blanc Acoustic Propagation Department Argentinian Navy Research Office(DIIV)Buenos Aires 1638Argentina UNIDEF(National Council of Scientific and Technical Research/Ministry of Defense) Buenos AiresArgentina

This work has a two-fold *** the one hand,the theoretical formulation of a three-dimensional(3D)acoustic propagation model for shallow waters with a constant sound speed is presented,based on the boundary element method(BEM),which uses a half-space Green function instead of the more conventional free-space Green *** the other hand,a numerical implementation is illustrated to explore the formulation in simple idealized cases,controlled by a few parameters,which provides necessary tests for the accuracy and performance of the *** half-space Green's function,which has been previously used in scattering and diffraction,adds terms to the usual expressions of the integral operators without altering their continuity *** against the wavenumber integration solution of the Pekeris waveguide suggest that the model allows an adequate prediction for the acoustic ***,numerical experiments in relation to the necessary mesh size for the description of the water-marine sediment interface lead to the conclusion that a transmission loss prediction with acceptable accuracy can be obtained with the use of a limited mesh around the desired evaluation region.

关键词： three-dimensional acoustic propagation boundary element method half-space Green function

Testicular expression of the TGF-<i>β</i>1 system and the control of Leydig cell proliferation

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Advances in Bioscience and Biotechnology 2013年第10期4卷 1-7页

作者： gonzalez Candela Rocio Calandra Ricardo Saul gonzalez-Calvar silvia Ines Institute of Biology and Experimental Medicine National Council for Scientific and Technical Research Buenos Aires Argentina Research Center of Biomedical Biotechnology Environmental and Diagnostic Studies Maimónides University Buenos Aires Ar- gentina

Transforming growth factor beta 1 (TGF-β1) is a key regulator that modulates male reproductive function. Testicular TGF-β1 modulates the steroidogenesis of Leydig cells, the organization of peritubular myoid cells, testis development and spermatogenesis. Several studies have indicated that TGF-β1 is involved in the tight balance between proliferative and apoptotic responses in the Leydig cells. In the present review, we summarize the direct effects of this cytokine in Leydig cells under normal and pathological conditions. We analyze the effect of TGF-β1 inLeydig cells depending on the type of receptors involved in the signaling pathway of TGF-β1. Our group has been analyzing the canonical and non canonical intracellular signaling pathways of TGF-β1 that are involved in the expression of proliferative and apoptotic markers in Leydig cells. On the basis of our studies and from those of other authors we conclude that the balance between the expression of TGF-β1 receptors and co receptors is of relevance in Leydig cell physiology and pathophisiology.

关键词： TGF-β1 Leydig ALK Endoglin