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71.
Y. P. Cruz R. S. Treichel E. Harsay K. D. Chi 《In vitro cellular & developmental biology. Animal》1993,29(8):671-675
Summary Immunosurgery is a useful technique for the isolation of inner cell masses from murine blastocysts. Conventionally, rabbit
antisera made ad hoc against murine splenic or fetal cells or fibroblasts have been used as antibody sources. We investigated
the feasibility of using commercially available rabbit antiserum to murine erythrocytes (anti-RBC) and compared it with rabbit
antiserum generated ad hoc to murine L-cells (anti-L-cell). Our results indicate that anti-RBC is at least as effective as
anti-L-cell serum for the immunosurgical isolation of inner cell masses, which became either miniblastocysts (later forming
outgrowths) or embryoid bodies (undergoing ectoderm-endodermlike differentiation within 48 h). Because anti-RBC is commercially
available, the technical modification described herein increases the accessibility of the immunosurgical protocol for the
isolation of murine inner cell masses. 相似文献
72.
We have isolated and characterized an antigen from normal human brain called p80, so called because it migrated with an Mr of 80 kDa on SDS PAGE. The Mr of 80 kDa consists of a protein of about 55-60 kDa and carbohydrate (20-25 kDa). The carbohydrate is almost entirely of the N-linked type, although a small amount of O-linked carbohydrate was detected. Cross-reactivity with monoclonal antibodies A3D8 and A1G3 showed that p80 could therefore be considered an isoform of the CD44 adhesion molecules. In addition, specific binding to hyaluronate which was not competed for by proteoglycan demonstrated that it involved different sites than the proteoglycan binding sites. We also observed that fucoidan and dextran sulphate increased the binding by 200-250% while chondroitin sulphate C also increased the binding but to a lesser extent. Heparin, heparan sulphate and chondroitin sulphates A and B did not have such an effect. The binding of p80 to hyaluronate was pH dependent with a maximum at pH 6.4. We concluded that p80 was an astrocyte specific adhesion molecule. 相似文献
73.
David Julian Arias-Chávez Patrick Mailloux-Salinas Jessica Ledesma Aparicio Elihu Campos-Pérez Omar Noel Medina-Campos José Pedraza-Chaverri Guadalupe Bravo 《Journal of cellular and molecular medicine》2023,27(20):3147-3156
Benign prostatic hyperplasia (BPH) is the most common adenoma in old men. Tomatoes are a rich source of bioactive compounds that, as well as selenium (Se), possess antioxidant and antiproliferative activity. The aim was to evaluate the therapeutic effect of Se in combination with a tomato extract in aged rats with BPH. Aged male Wistar rats were divided in the following groups (n = 10 rats/group): Control (C), BPH, BPH + Finasteride (BPH + F), BPH + Tomato Lipidic Extract (BPH + E), BPH + Selenium (BPH + S) and BPH plus E plus S (BPH + E + S). After 4 weeks of treatment, prostate weight, diuresis, antioxidants enzymes, prooxidants and inflammatory markers, growth factors and androgens were determined. BPH + E + S reduced prostate weight by 59.29% and inhibited growth by 99.35% compared to BPH + F which only decreased weight and inhibited growth by 15.31% and 57.54%, respectively. Prooxidant markers were higher with BPH + F (49.4% higher vs. BPH), but BPH + E + S decreased these markers (94.27% vs. BPH) and increased antioxidant activity. Finally, diuresis was higher with the BPH + E + S combination and markers of inflammation and growth factors were significantly lower with respect to BPH + F. Our findings provide a beneficial and protective therapeutic option of E + S directed against androgens, oxidative stress and inflammation that regulates cell proliferation in the prostate gland. 相似文献
74.
Felisa Rey Paulo Cartaxana Sónia Cruz Tânia Melo M. Rosário Domingues 《Journal of phycology》2023,59(5):1025-1040
Marine algae are one of the most important sources of high-value compounds such as polar lipids, omega-3 fatty acids, photosynthetic pigments, or secondary metabolites with interesting features for different niche markets. Acetabularia acetabulum is a macroscopic green single-celled alga, with a single nucleus hosted in the rhizoid. This alga is one of the most studied dasycladalean species and represents an important model system in cell biology studies. However, its lipidome and pigment profile have been overlooked. Total lipid extracts were analyzed using hydrophilic interaction liquid chromatography-high resolution mass spectrometry (HILIC-HRMS), tandem mass spectrometry (MS/MS), and high-performance liquid chromatography (HPLC). The antioxidant capacity of lipid extracts was tested using DPPH and ABTS assays. Lipidomics identified 16 polar lipid classes, corresponding to glycolipids, betaine lipids, phospholipids, and sphingolipids, with a total of 191 lipid species, some of them recognized by their bioactivities. The most abundant polar lipids were glycolipids. Lipid classes less studied in algae were identified, such as diacylglyceryl-carboxyhydroxymethylcholine (DGCC) or hexosylceramide (HexCer). The pigment profile of A. acetabulum comprised carotenoids (17.19%), namely cis-neoxanthin, violaxanthin, lutein and β,β-carotene, and chlorophylls a and b (82.81%). A. acetabulum lipid extracts showed high antioxidant activity promoting a 50% inhibition (IC50) with concentrations of 57.91 ± 1.20 μg · mL−1 (438.18 ± 8.95 μmol Trolox · g−1 lipid) in DPPH and 20.55 ± 0.60 μg · mL−1 in ABTS assays (918.56 ± 27.55 μmol Trolox · g−1 lipid). This study demonstrates the potential of A. acetabulum as a source of natural bioactive molecules and antioxidant compounds. 相似文献
75.
da Cunha Cruz Yasmini Scarpa Ana Lívia Martins Díaz Alejandro Sandria Pereira Marcio Paulo de Castro Evaristo Mauro Pereira Fabricio José 《Journal of plant research》2023,136(5):665-678
Journal of Plant Research - Precipitation is an important climatic element that defines the hydrological regime, and its seasonal variation produces annual dry and wet periods in some areas. This... 相似文献
76.
Janaine Almeida Neto Daniel Amando Nery Katia Simoni Bezerra Lima Maria Eduarda Gomes da Cruz Silva Tarcísio Cícero de Lima Araújo Nathália Andrezza Carvalho de Souza Rodolfo Hideki Vicente Nishimura Camila de Souza Araújo Ana Paula de Oliveira Jackson Roberto Guedes da Silva Almeida Larissa Araújo Rolim 《化学与生物多样性》2023,20(3):e202201039
This article describes the phytochemical study of Cannabis sativa roots from northeastern Brazil. The dried plant material was pulverized and subjected to exhaustive maceration with ethanol at room temperature, obtaining the crude ethanolic extract (Cs-EEBR). The volatile compounds were analyzed by gas chromatography coupled with mass spectrometry (GC/MS), which allowed to identify 22 compounds by comparing the linear retention index (LRI), the similarity index (SI) and the fragmentation pattern of the constituents with the literature. By this technique the major compounds identified were: friedelan-3-one and β-sitosterol. In addition, two fractions were obtained from Cs-EEBR by classical column chromatography and preparative thin layer chromatography. These fractions were analyzed by NMR and IR and together with the mass spectrometry data allowed to identify the compounds: epifriedelanol, friedelan-3-one, β-sitosterol and stigmasterol. The study contributed to the phytochemical knowledge of Cannabis sativa, specifically the roots, as there are few reports on the chemical constituents of this part of the plant. 相似文献
77.
Roberto de la Herrán Miguel Hermida Juan Andres Rubiolo Jèssica Gómez-Garrido Fernando Cruz Francisca Robles Rafael Navajas-Pérez Andres Blanco Paula Rodriguez Villamayor Dorinda Torres Pablo Sánchez-Quinteiro Daniel Ramirez Maria Esther Rodríguez Alberto Arias-Pérez Ismael Cross Neil Duncan Teresa Martínez-Peña Ana Riaza Adrian Millán M. Cristina De Rosa Davide Pirolli Marta Gut Carmen Bouza Diego Robledo Laureana Rebordinos Tyler Alioto Carmelo Ruíz-Rejón Paulino Martínez 《Molecular ecology resources》2023,23(4):886-904
Sex determination (SD) shows huge variation among fish and a high evolutionary rate, as illustrated by the Pleuronectiformes (flatfishes). This order is characterized by its adaptation to demersal life, compact genomes and diversity of SD mechanisms. Here, we assembled the Solea senegalensis genome, a flatfish of great commercial value, into 82 contigs (614 Mb) combining long- and short-read sequencing, which were next scaffolded using a highly dense genetic map (28,838 markers, 21 linkage groups), representing 98.9% of the assembly. Further, we established the correspondence between the assembly and the 21 chromosomes by using BAC-FISH. Whole genome resequencing of six males and six females enabled the identification of 41 single nucleotide polymorphism variants in the follicle stimulating hormone receptor (fshr) consistent with an XX/XY SD system. The observed sex association was validated in a broader independent sample, providing a novel molecular sexing tool. The fshr gene displayed differential expression between male and female gonads from 86 days post-fertilization, when the gonad is still an undifferentiated primordium, concomitant with the activation of amh and cyp19a1a, testis and ovary marker genes, respectively, in males and females. The Y-linked fshr allele, which included 24 nonsynonymous variants and showed a highly divergent 3D protein structure, was overexpressed in males compared to the X-linked allele at all stages of gonadal differentiation. We hypothesize a mechanism hampering the action of the follicle stimulating hormone driving the undifferentiated gonad toward testis. 相似文献
78.
79.
M. G. Carneiro-da-Cunha E. P. Melo J. M. S. Cabral M. R. Aires-Barros 《Bioprocess and biosystems engineering》1996,15(3):151-157
This work reports the extraction and back-extraction of an intracellular recombinant cutinase from complex biological media using AOT reversed micelles in isooctane. Cutinase was recovered from different complex media namely, fermentation broths and supernatants after cell disruption by osmotic shock and sonication. The application of the AOT reversed micellar system to the extraction of cutinase allowed activity yields and purification factors ranging from about 5% to 50% and 1.2 to 10.2, respectively, depending on the biological medium.Maria das Graças Carneiro da Cunha, from ITEP-Instituto Tecnológico do Estado de Pernambuco, acknowledges a Ph.D fellowship from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and Centro de Pesquisa Aggeu Magalhães, Recife — PE — Brasil. E. P. Melo thanks Junta Nacional de Investigação Científica, Lisboa, Portugal, for providing a Ph.D. fellowship. The scientific support given by Prof. Sílvia M. B. Costa for the spectroscopic data and further discussions are particularly acknowledged.This work was partly financed by the BRIDGE and BIOTECHNOLOGY Programmes (Contracts BIOT-CT91-0274(DTEE) and BIOT 2 CT-943016). 相似文献
80.
Viral coat protein is targeted to, but does not gate, plasmodesmata during cell-to-cell movement of potato virus X 总被引:4,自引:0,他引:4
K.J. Oparka A.G. Roberts I.M. Roberts D.A.M. Prior S. Santa Cruz 《The Plant journal : for cell and molecular biology》1996,10(5):805-813
The coat protein (CP) of potato virus X was localized immunocytochemically in infected leaves of susceptible Nicotiana species and shown to be targeted to the central cavity of plasmodesmata in virus-infected cells. A viral deletion mutant, in which the CP gene was replaced with the gene for the green fluorescent protein (GFP), was restricted to single, inoculated cells. However, movement of the mutant virus was rescued on transgenic plants constitutively expressing the CP gene, and the CP was again targeted to plasmodesmata. The CP was not localized to plasmodesmata in uninfected transgenic plants and, in contrast to the plasmodesmata of PVX-infected cells, the plasmodesmata of the transgenic plants did not allow the passage of 10 kDa fluorescent dextrans. We propose that the CP is not involved in plasmodesmal gating per se , but is necessary for transport of the viral RNA to, and possibly through, plasmodesmata. 相似文献