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Crystal Structure and Synthesis of 3β-(p-Iodobenzoyloxy)-16α,17α-Epoxypregn-4-En-6,20-Dione

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Crystal Structure Theory and Applications 2014年第2期3卷 39-47页

作者： Alejandra Chávez-Riveros Marisa Cabeza Eugene Bratoeff manuel soriano-garcía Departamento de Sistemas Biológicos Universidad Autónoma Metropolitana Unidad Xochimilco México D. F. México Facultad de Química UNAM Ciudad Universitaria México D. F. México Instituto de Química Universidad Nacional Autónoma de México Circuito Exterior Ciudad Universitaria México D. F. México

3β-(p-iodobenzoyloxy)-16α,17α-epoxypregn-4-en-6,20-dione (7), C28H31O5I, was synthesized from the commercially available 16-dehydropregnenolone acetate. X-ray diffraction analysis of (1) demonstrated that it consisted of four rings, three six-membered rings (A, B and C) and one five-membered ring (D). A, B, C and D rings occur in an envelope, deformed chair, deformed chair, and the half chair conformations, respectively. The absolute configurations of 7 for the chiral centers are 3S, 8S, 9S, 10R, 13S and 14S. The crystal of 3β-(p-iodobenzoyloxy)-16α,17α-epoxypregn-4-en-6,20-dione is in monoclinic crystal system with space group P21, lattice constants: a = 10.8567 (11), b = 7.5479 (7), c = 16.0391 (16) Å, β = 109.473 (1)°, V = 1239.1 (2) Å3, Dx = 1.518 g/cm3 and Z = 2. The molecules in the crystal are stabilized by C-H···O interactions and van der Waals forces.

关键词： Progesterone Derivatives Androgen Receptor 5-Alpha-Reductase Inhibitors Human Prostate

Peptides and Peptidomics: A Tool with Potential in Control of Plant Viral Diseases

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Advances in Microbiology 2014年第9期4卷 539-548页

作者： José Silvestre Mendoza-Figueroa manuel soriano-garcía Laura Beatriz Valle-Castillo Jesús Méndez-Lozano Instituto de Química Universidad Nacional Autónoma de México Ciudad Universitaria Coyoacán Mexico City Mexico Instituto Politécnico Nacional CIIDIR Unidad Sinaloa Guasave Mexico

Plant viruses are the most infectious agents in commercially important crops worldwide. Plant viral diseases are important because both decreased yielding and quality of fruits, flowers or vegetables lead to million-dollar losses in production. At present there are no reports which suggest a direct control of plant virus. A new strategy for plant virus control has been raised since 13 years ago—the use of peptides. Peptides could offer a direct interaction by affinity selection against viral proteins involved in infection cycle, like capsid or movement protein (e.g.) and affect viral replication. Peptidomics, as a new tool to study peptides, led us screening and selecting the best peptide with antiviral activity, and re-designing it to enhance the biological effect as well as the potential of bioactivity of those peptides secreted by microbes present in soil. In this paper we review current aspects in the use of peptides and peptidomics as a strategy to study new methods that lead a direct control against plant viral diseases.

关键词： Peptidomics Plant Virus Peptides Peptaiboles Mass Spectrometry Aptamers

Facile Preparation of 1,2-Diols from Chalcones: An NMR Spectroscopy and X-Ray Crystallography Study

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International Journal of Organic Chemistry 2015年第3期5卷 137-146页

作者： Marco A. Obregón-Mendoza María Miriam Estévez-Carmona Carolina Escobedo-Martínez manuel soriano-garcía Raúl G. Enríquez Instituto de Química Universidad Nacional Autónoma de México Ciudad Universitaria México City México Departamento de Farmacia División de Ciencias Naturales y Exactas del Campus Guanajuato Universidad de Guanajuato México

Structures of 2-(naphthalen-2-ylmethyl)-2,3-dihydro-1H-indene-1,2-diol (C20H18O2), compound 1 and 1-(3,4-dimethoxyphenyl)-3-methoxy-3-(4-nitrophenyl)propane-1,2-diol chloroform (C18H21NO7·CHCl3) compound 2 were established by spectral and X-ray diffraction studies. Compound 1 crystallizes in the orthorhombic space group P212121 with unit cell parameters a = 5.2177 (6), b = 13.903 (2), c = 21.121 (2) A, Z = 4. Compound 2 crystallizes in the triclinic space group P-1 with unit cell parameters a = 9.238 (1), b = 9.879 (1), c = 12.636 (1) A, α = 102.004 (1), β = 92.356 (1), γ = 90.779 (1)o, Z = 2. These two new molecules arise from a facile preparation of 1,2-diols from chalcones and have been fully characterized. Based on the crystallographic information obtained for compound 1, the relative configuration for the chiral centers is 1S and 2S. In structure 1, both hydroxyl groups adopt an anti-conformation with a torsion angle O1-C1-C2-O2 value of 93.1 (2)o [in molecule 2, both hydroxyl groups adopt a trans-conformation with a torsion angle O1-C1-C2-O2 value of -171.0 (2)。]. In both structures, the molecules in the crystal are linked by intermolecular hydrogen bonds O-H···O and C-H···O interactions and adjacent molecules are interconnected by intermolecular weak C-H···π and C-H···Cl interactions which give additional support to molecular packing stability.

关键词： C20H18O2 C18H21NO7·CHCl3 Diols Chal-cones

Crystal Structure, Synthesis and Biological Activity of Ether and Ester Trans-Ferulic Acid Derivatives

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International Journal of Organic Chemistry 2018年第4期8卷 359-377页

作者： Marco A. Obregón-Mendoza M. Mirian Estévez-Carmona Yair Alvarez-Ricardo William Meza-Morales Carolina Escobedo-Martínez manuel soriano-garcía Raúl G. Enríquez Instituto de Química Universidad Nacional Autónoma de México Ciudad de México México Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional México City México Departamento de Farmacia División de Ciencias Naturales y Exactas Universidad de Guanajuato Guanajuato México

The structures of methoxymethyl (E)-3-(4-hydroxy-3-methoxyphenyl)acrylate, 2;(E)-3-(3-methoxy-4-(methoxymethoxy)phenyl)acrylic acid, 3;methyl (E)- 3-(4-(benzyloxy)-3-methoxyphenyl)acrylate, 4;benzyl (E)-3-(4-(benzyloxy)- 3-methoxyphenyl)acrylate, 6;and (E)-3-(4-(benzyloxy)-3-methoxyphenyl)- acrylic acid, 7;were established by spectroscopic and X-ray diffraction studies. Structure 2 is a new com-pound. Compounds with free phenolic hydroxyls ***. methyl (E)-3-(4-hydroxy-3-methoxyphenyl)acrylate 1, 2 and ben-zyl(E)-3-(4-hydroxy-3-methoxyphenyl)acrylate 5, showed scavenging free- radical and antioxidant activity while moderate scavenging free-radical was observed in compound 3. Moderate inhibition of lipid peroxidation was observed for 7. Compound 5 exerted significant inhibition of cell growth in PC-3, K562 tumor cell lines and 4 exhibited the largest cytotoxic effect upon the K562 cell line.

关键词： Trans-Ferulic Acid Crystal Structures Antioxidant Activity Antitumor Scavenging Free-Radicals

Assessing Joint Simulation and Estimation Approaches in Geometallurgical Modeling

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Journal of Geoscience and Environment Protection 2025年第1期13卷 316-330页

作者： Farzaneh Khorram Gabriel Pais manuel Reyes Facultad de Ingeniera Universidad Andres Bello Santiago Chile

Given that energy costs are a significant component of overall processing costs in mineral plants, reducing these costs through process optimization or technology adoption enhances the technical and financial feasibility of a deposit. Geometallurgical modeling plays a key role in understanding the relationship between material characteristics, mine planning, and processing stages, ultimately contributing to more efficient resource management and cost reduction in mineral processing. This study aims to develop a block model for evaluating comminution energy consumption (CEC) and identifying blocks with the highest energy usage potential during the grinding process in a specified region. Therefore, by applying advanced geostatistical techniques, including joint estimation and simulation based on geometallurgical data from multiple mineral processing stages, we predict CEC across the study area. The dataset encompasses 2.754 drill samples and a block model with 4.680 blocks. In this effort, imulation techniques, such as Plurigaussian and Turning Bands, provided more realistic outcomes than cokriging, considering the unique characteristics of geometallurgical data and the limitations of kriging methods.

关键词： Geometallurgy Multivariate Analysis Plurigaussian Turning Band Method Cokriging

First Occurrence of Paragordius varius in Different Species of Acrididae in Irapuato, Guanajuato, Mexico

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Advances in Entomology 2025年第1期13卷 120-125页

作者： manuel Dario Salas-Araiza Ilse Alejandra Huerta-Arredondo Rafael Guzmán-Mendoza Itzel Berenice Aguilar-Campos Daniela de Jesús Bustos-Gallaga Miguel Angel Rocha-garcía David Isaías Rodríguez-Vázquez Agronomy Department Life Sciences Division University of Guanajuato Irapuato Mexico

Acridid populations have increased significantly in recent years, causing damage to crops. Having biocontrol tools is important as it will help reduce the use of insecticides. This study reports the presence of Paragordius varius in grasshoppers for the first time in Irapuato, Guanajuato, Mexico. Samples were taken from the grass around a water pond. A total of 1,225 grasshoppers were dissected to observe the presence of the worm. Seven species of grasshoppers were identified, with the most abundant species being Melanoplus differentialis. The parasitoid Paragordius varius, a nematomorph, parasitized male M. differentialis in greater numbers. This work is the first record of this parasitoid in Mexico and contributes to the knowledge of the biological control of acridids in Mexico.

关键词： Grasshoppers Paragordius varius Parasitism Nematomorph Biological Control

Cerebral cortex contributions to Parkinson's disease tremor:what exactly generates the tremor?

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Neural Regeneration Research 2025年第12期20卷 3535-3536页

作者： manuel Bange Hao Ding Muthuraman Muthuraman Informatics for Medical Technology Institute of Computer ScienceUniversity AugsburgAugsburgGermany Department of Neurology Neural Engineering with Signal Analytics and Artificial Intelligence(NESA-AI)University Clinic WürzburgWürzburgGermany

Pathological tremor is one of the cardinal symptoms in Parkinson's disease (PD).Tremor is comprised of involuntary,rhythmic,a nd oscillating movements that can vary according to the circumstances under which they occur,the body parts that are involved,and the frequency at which they *** example,tremors can be mild to severe,are stress sensitive,and can affect arms,legs,or the head (Dirkx and Bologna,2022).

关键词： tremor cortex exactly

An update on iron physiology

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World Journal of Gastroenterology 2009年第37期15卷 4617-4626页

作者： manuel Muoz Isabel Villar José Antonio garcía-Erce Transfusion Medicine School of Medicine University of Málaga Málaga 29071 Spain Department of Hospital Pharmacy University Hospital Miguel Servet Zaragoza 50009 Spain Hematology and Hemotherapy University Hospital Miguel Servet Zaragoza 50009 Spain

Iron is an essential micronutrient, as it is required for adequate erythropoietic function, oxidative metabolism and cellular immune responses. Although the absorption of dietary iron (1-2 mg/d) is regulated tightly, it is just balanced with losses. Therefore, internal turnover of iron is essential to meet the requirements for erythropoiesis (20-30 mg/d). Increased iron requirements, limited external supply, and increased blood loss may lead to iron deficiency (ID) and iron-deficiency anemia. Hepcidin, which is made primarily in hepatocytes in response to liver iron levels, inflammation, hypoxia and anemia, is the main iron regulatory hormone. Once secreted into the circulation, hepcidin binds ferroportin on enterocytes and macrophages, which triggers its internalization and lysosomal degradation. Thus, in chronic inflammation, the excess of hepcidin decreases iron absorption and prevents iron recycling, which results in hypoferremia and iron-restricted erythropoiesis, despite normal iron stores (functional ID), and anemia of chronic disease (ACD), which can evolve to ACD plus true ID (ACD + ID). In contrast, low hepcidin expression may lead to iron overload, and vice versa. Laboratory tests provide evidence of iron depletion in the body, or reflect iron-deficient red cell production. The appropriate combination of these laboratory tests help to establish a correct diagnosis of ID status and anemia.

关键词： Iron metabolism Iron deficiency Functionaliron deficiency, Hepcidin Anemia of chronic disease

Blood transfusion for the treatment of acute anaemia in inflammatory bowel disease and other digestive diseases

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World Journal of Gastroenterology 2009年第37期15卷 4686-4694页

作者： José Antonio garcía-Erce Fernando Gomollón manuel Muoz Transfusion Medicine and Apheresis Unit Haematology and Haemotherapy Regional Service "Miguel Servet" University Hospital Zaragoza 50009 Spain Gastroenterology Unit University Clinical Hospital and Biomedical Investigation Center at Digestive and Hepatic Disease Network c/San Juan Bosco 15 Zaragoza 50009 Spain Transfusion Medicine School of Medicine University of Málaga Málaga 29071 Spain

Allogeneic blood transfusion (ABT) is frequently used as the first therapeutic option for the treatment of acute anaemia in patients with inflammatory bowel disease (IBD), especially when it developed due to gastrointestinal or perioperative blood loss, but is not risk-free. Adverse effects of ABT include, but are not limited to, acute hemolytic reaction (wrong blood or wrong patient), febrile non-hemolytic transfusional reaction, bacterial contamination, transfusion-related acute lung injury, transfusion associated circulatory overload, transfusion-related immuno-modulation, and transmission of almost all infectious diseases (bacteria, virus, protozoa and prion), which might result in increased risk of morbidity and mortality. Unfortunately, the main physiological goal of ABT, i.e. to increase oxygen consumption by the hypoxic tissues, has not been well documented. In contrast, the ABT is usually misused only to increase the haemoglobin level within a f ixed protocol [mostly two by two packed red blood cell (PRC) units] independently of the patient' s tolerance to normovolemic anaemia or his clinical response to the transfusion of PRC units according to a "one-by-one" administration schedule. Evidencebased clinical guidelines may promote best transfusion practices by implementing restrictive transfusion protocols, thus reducing variability and minimizing the avoidable risks of transfusion, and the use of autologous blood and pharmacologic alternatives. In this regard, preoperative autologous blood donation (PABD) consistently diminished the frequency of ABT, although its contribution to ABT avoidance is reduced when performed under a transfusion protocol. In addition, interpretation of utility of PABD in surgical IBD patients is hampered by scarcity of published data. However, the role of autologous red blood cells as drug carriers is promising. Finally, it must be stressed that a combination of methods used within wellconstructed protocols will offer better prospe

关键词： Anaemia Blood transfusion Autologous blood transfusion Inflammatory bowel diseases Risk assessment