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1.
Mucosal Immunol ; 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31932715

RESUMO

Mice deficient in the IL-10 pathway are the most widely used models of intestinal immunopathology. IL-17A is strongly implicated in gut disease in mice and humans, but conflicting evidence has drawn IL-17's role in the gut into question. IL-22 regulates antimicrobial and repair activities of intestinal epithelial cells (IECs) and is closely associated with IL-17A responses but it's role in chronic disease is uncertain. We report that IL-22, like IL-17A, is aberrantly expressed in colitic Il10-/- mice. While IL-22+ Th17 cells were elevated in the colon, IL-22-producing ILC3s were highly enriched in the small intestines of Il10-/- mice. Remarkably, Il10-/-Il22-/- mice did not develop colitis despite retaining high levels of Th17 cells and remaining colonized with colitogenic Helicobacter spp. Accordant with IL-22-induced IEC proliferation, the epithelia hyperplasia observed in Il10-/- animals was reversed in Il10-/-Il22-/- mice. Also, the high levels of antimicrobial IL-22-target genes, including Reg3g, were normalized in Il10-/-Il22-/- mice. Consistent with a heightened antimicrobial environment, Il10-/- mice had reduced diversity of the fecal microbiome that was reestablished in Il10-/-Il22-/- animals. These data suggest that spontaneous colitis in Il10-/- mice is driven by IL-22 and implicates an underappreciated IL-10/IL-22 axis in regulating intestinal homeostasis.

2.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(11): 1130-1132, 2019 Nov 10.
Artigo em Chinês | MEDLINE | ID: mdl-31703143

RESUMO

OBJECTIVE: To analyze the hematological characteristics of a patient with Hb Ottawa in conjunction with ß -thalassemia. METHODS: Peripheral blood samples from the proband and her parents were collected and subjected to red blood cell analysis and hemoglobin electrophoresis. Genotypes of α - and ß -globin genes were also analyzed. RESULTS: The proband and her mother were both heterozygotes for Hb Ottawa and ß -thalassemia variant IVS II-654, and presented with typical ß -thalassemia trait featuring hypochromic microcytic anemia. An abnormal hemoglobin band was detected upon electrophoresis. CONCLUSION: Co-existence of Hb Ottawa and ß -thalassemia may not aggravate the phenotype.


Assuntos
Hemoglobinas Anormais/genética , Talassemia beta/genética , Feminino , Testes Genéticos , Heterozigoto , Humanos , alfa-Globinas/genética , Globinas beta/genética
3.
BMC Complement Altern Med ; 19(1): 151, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31242894

RESUMO

BACKGROUND: Costunolide, a sesquiterpene lactone extracted from Radix Aucklandiae, has the activity against multiple cancers. However, the effect of costunolide on gastric cancer (GC) have remained to be ambiguous. In this study, we investigated the underlying mechanisms of apoptosis induced by costunolide in human gastric adenocarcinoma BGC-823 cells in vitro and in vivo. METHODS: The viability of BGC-823 cells was detected by MTT assay. The apoptosis and mitochondrial membrane potential (ΔΨm) of BGC-823 cells induced by costunolide were analyzed by flow cytometry. The inhibiton of costunolide on human gastric adenocarcinoma was estimated in xenografts in nude mice. Apoptosis related proteins and genes were detected by Western blot and Q-PCR. RESULTS: Costunolide inhibited the viability of BGC-823 cells in a time and concentration dependent manner. Costunolide induced the apoptosis and lowered the ΔΨm of BGC-823 cells significantly. Costunolide increased the expression of Bax, cleaved caspase 9, cleaved caspase 7, cleaved caspase 3 and cleaved poly ADP ribose polymerase (PARP) proteins and decreased the expression of Bcl-2, pro-caspase 9, pro-caspase 7, pro-caspase 3 and PARP proteins. Costunolide upregulated the expression of puma, Bak1 and Bax mRNA and downregulated the expression of Bcl-2 mRNA. In addition, we demonstrated that costunolide inhibited the growth and induced apoptosis of BGC-823 cells xenografted in athymic nude mice. Costunolide increased the expression of cleaved caspase 9, cleaved caspase 3 and Bax proteins and decreased the expression of Bcl-2 protein in xenografted tumor. Costunolide upregulated the expression of puma and Bax mRNA and decreased the expression of Bcl-2 mRNA in xenografted tumor. CONCLUSIONS: Collectively, our results suggested that costunolide induced mitochondria-mediated apoptosis in human gastric adenocarcinoma BGC-823 cells and could be the candidate drug against GC in clinical practice.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Fitogênicos/administração & dosagem , Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Sesquiterpenos/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/fisiopatologia , Animais , Caspases/genética , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/fisiopatologia
4.
Nanomaterials (Basel) ; 9(2)2019 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-30781506

RESUMO

Metal⁻organic framework (MOF)-based derivatives are attracting increased interest in various research fields. In this study, nano-cellulose MOF-derived carbon-doped CuO/Fe3O4 nanocomposites were successfully synthesized via direct calcination of magnetic Cu-BTC MOF (HKUST-1)/Fe3O4/cellulose microfibril (CMF) composites in air. The morphology, structure, and porous properties of carbon-doped CuO/Fe3O4 nanocomposites were characterized using SEM, TEM, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), and vibrating sample magnetometry (VSM). The results show that the as-prepared nanocomposite catalyst is composed of Fe3O4, CuO, and carbon. Compared to the CuO/Fe3O4 catalyst from HKUST-1/Fe3O4 composite and CuO from HKUST-1, this carbon-doped CuO/Fe3O4 nanocomposite catalyst shows better catalytic efficiency in reduction reactions of 4-nitrophenol (4-NP), methylene blue (MB), and methyl orange (MO) in the presence of NaBH4. The enhanced catalytic performance of carbon-doped CuO/Fe3O4 is attributed to effects of carbon preventing the aggregation of CuO/Fe3O4 and providing high surface-to-volume ratio and chemical stability. Moreover, this nanocomposite catalyst is readily recoverable using an external magnet due to its superparamagnetic behavior. The recyclability/reuse of carbon-doped CuO/Fe3O4 was also investigated.

5.
Nanoscale Res Lett ; 13(1): 202, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-29987472

RESUMO

A facile process to prepare zinc oxide (ZnO) nanoparticles from an aqueous zinc chloride (ZnCl2) solution and an aqueous hydroxide solution under a glycerol stabilizer at room temperature was developed. ZnCl2 aqueous solutions as concentrated as 65-80 wt% were used as the concentrated zinc source. The concentration of ZnCl2 solutions and the molar ratio of glycerol to Zn2+ had obvious effects on the sizes and shapes of the ZnO nanoparticles. The shape of ZnO nanoparticles changed from rods approximately 50-120 nm long and 30-70 nm in diameter to globular with diameters of approximately 20 nm with the increasing of the concentration of the ZnCl2 solution and the mole ratio of glycerol to Zn2+. Glycerol, as a stabilizer, played an important role in the formation of ZnO nanostructures at room temperature, even for a highly concentrated zinc source.

6.
Membranes (Basel) ; 7(3)2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-28895877

RESUMO

Membrane-based separation technology has attracted great interest in many separation fields due to its advantages of easy-operation, energy-efficiency, easy scale-up, and environmental friendliness. The development of novel membrane materials and membrane structures is an urgent demand to promote membrane-based separation technology. Graphene oxide (GO), as an emerging star nano-building material, has showed great potential in the membrane-based separation field. In this review paper, the latest research progress in GO-based membranes focused on adjusting membrane structure and enhancing their mechanical strength as well as structural stability in aqueous environment is highlighted and discussed in detail. First, we briefly reviewed the preparation and characterization of GO. Then, the preparation method, characterization, and type of GO-based membrane are summarized. Finally, the advancements of GO-based membrane in adjusting membrane structure and enhancing their mechanical strength, as well as structural stability in aqueous environment, are particularly discussed. This review hopefully provides a new avenue for the innovative developments of GO-based membrane in various membrane applications.

7.
Nanoscale Res Lett ; 11(1): 200, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27075342

RESUMO

A new production method of zinc oxide (ZnO)-starch nanocomposite was invented in this study. Starch was dissolved in zinc chloride (ZnCl2) solution (65 wt%) at 80 °C. Then, ZnO-starch nanocomposite was achieved when the pH of the solution was adjusted to 8.4 by NaOH solution (15 wt%). ZnO nanoparticles were also obtained when the generated ZnO-starch nanocomposite was calcined at 575 °C. The properties of ZnO-starch nanocomposite and ZnO nanoparticle were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results indicated that the sizes of ZnO-starch composite and ZnO particle were 40-60 nm. UV blocking effect was observed from both ZnO-starch nanocomposite and ZnO nanoparticle. The ZnO-starch nanocomposite was used to directly coat the surface of plain paper with a laboratory paper coater. The surface strength and smoothness of paper were improved by the coating of ZnO-starch nanocomposite. The antibacterial property was also identified from the coated paper.

8.
PLoS One ; 10(10): e0140603, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26465917

RESUMO

This paper describes self-reinforced antibacterial and oil-resistant properties that were successfully prepared by surface selective dissolution of filter paper in a NaOH/Urea/ZnO (weight ratio of 8:12:0.25) aqueous solution. The effect of the processing time on the mechanical properties of this paper was evaluated at -12°C. The paper morphologies were characterized using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The oil-resistance and antibacterial properties of the produced paper were also investigated. Excellent mechanical properties were observed for an optimized handling time. The tensile and burst strengths of the modified paper were in excess of 100% of the original. Meanwhile, the treated paper was completely oil-resistant within 24 h and demonstrated good antibacterial properties when exposed to Staphylococcus aureus. The traces of residual zinc oxide were found to be safe for food.


Assuntos
Antibacterianos , Óleos , Papel , Hidróxido de Sódio , Ureia , Óxido de Zinco , Fenômenos Mecânicos , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
9.
PLoS One ; 10(6): e0129623, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26070149

RESUMO

Malaria, the disease caused by Plasmodium parasites, remains a major global health burden. The liver stage of Plasmodium falciparum infection is a leading target for immunological and pharmacological interventions. Therefore, novel approaches providing specific detection and isolation of live P. falciparum exoerythrocytic forms (EEFs) are warranted. Utilizing a recently generated parasite strain expressing green fluorescent protein (GFP) we established a method which, allows for detection and isolation of developing live P. falciparum liver stages by flow cytometry. Using this technique we compared the susceptibility of five immortalized human hepatocyte cell lines and primary hepatocyte cultures from three donors to infection by P. falciparum sporozoites. Here, we show that EEFs can be detected and isolated from in vitro infected cultures of the HC-04 cell line and primary human hepatocytes. We confirmed the presence of developing parasites in sorted live human hepatocytes and characterized their morphology by fluorescence microscopy. Finally, we validated the practical applications of our approach by re-examining the importance of host ligand CD81 for hepatocyte infection by P. falciparum sporozoites in vitro and assessment of the inhibitory activity of anti-sporozoite antibodies. This methodology provides us with the tools to study both, the basic biology of the P. falciparum liver stage and the effects of host-derived factors on the development of P. falciparum EEFs.


Assuntos
Citometria de Fluxo , Fígado/parasitologia , Malária Falciparum/parasitologia , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/isolamento & purificação , Linhagem Celular , Linhagem Celular Transformada , Células Cultivadas , Citometria de Fluxo/métodos , Expressão Gênica , Genes Reporter , Hepatócitos/metabolismo , Hepatócitos/parasitologia , Humanos , Estágios do Ciclo de Vida , Esporozoítos , Tetraspanina 28/metabolismo
10.
PLoS One ; 8(9): e75321, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24086507

RESUMO

Control of parasite replication exerted by MHC class I restricted CD8+ T-cells in the liver is critical for vaccination-induced protection against malaria. While many intracellular pathogens subvert the MHC class I presentation machinery, its functionality in the course of malaria replication in hepatocytes has not been characterized. Using experimental systems based on specific identification, isolation and analysis of human hepatocytes infected with P. berghei ANKA GFP or P. falciparum 3D7 GFP sporozoites we demonstrated that molecular components of the MHC class I pathway exhibit largely unaltered expression in malaria-infected hepatocytes until very late stages of parasite development. Furthermore, infected cells showed no obvious defects in their capacity to upregulate expression of different molecular components of the MHC class I machinery in response to pro-inflammatory lymphokines or trigger direct activation of allo-specific or peptide-specific human CD8+ T-cells. We further demonstrate that ectopic expression of circumsporozoite protein does not alter expression of critical genes of the MHC class I pathway and its response to pro-inflammatory cytokines. In addition, we identified supra-cellular structures, which arose at late stages of parasite replication, possessed the characteristic morphology of merosomes and exhibited nearly complete loss of surface MHC class I expression. These data have multiple implications for our understanding of natural T-cell immunity against malaria and may promote development of novel, efficient anti-malaria vaccines overcoming immune escape of the parasite in the liver.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Genes MHC Classe I/imunologia , Hepatócitos/imunologia , Malária/imunologia , Plasmodium/crescimento & desenvolvimento , Primers do DNA/genética , Genes MHC Classe I/genética , Hepatócitos/parasitologia , Humanos , Malária/metabolismo , Vacinas Antimaláricas/imunologia , Proteínas de Protozoários/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reprodução/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Cell Mol Life Sci ; 69(17): 2833-42, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22415323

RESUMO

The world of RNAs is much more complex than previously thought, and has rapidly emerged as one of the most actively researched topics in the life sciences. Recently, two findings in this field were reported and given special attention: promoter-associated RNAs (paRNAs), a novel class of RNAs with numerous potential functions; and promoter-targeted RNA-induced transcriptional gene regulation, a new regulatory mechanism to control transcription. In this review, we summarize the studies in these two areas, and outline the current understanding with respect to the potential biological functions of paRNAs, and the molecular mechanisms of promoter-targeted RNA-induced transcriptional gene silencing and activation. Additionally, we seek to integrate these two areas, as paRNAs may have potential biological links with promoter-targeted RNA-induced transcriptional gene regulation. Finally, we will discuss the significance of identifying paRNAs and the possible use of promoter-targeted RNAs in gene regulation and therapy.


Assuntos
Regulação da Expressão Gênica , Regiões Promotoras Genéticas/genética , RNA/genética , Transcrição Genética , Animais , Humanos
12.
J Cell Mol Med ; 16(1): 129-41, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21342435

RESUMO

The syntaxin 11 (STX11) gene is mutated in a proportion of patients with familial haemophagocytic lymphohistiocytosis (FHL) and exocytosis of cytotoxic granules is impaired in STX11-deficient NK cells. However, the subcellular localization, regulation of expression and molecular function of STX11 in NK cells and other cytotoxic lymphocytes remain unknown. Here we demonstrate that STX11 expression is strictly controlled by several mechanisms in a cell-type-specific manner and that the enzymatic activity of the proteasome is required for STX11 expression in NK cells. In resting NKL cells, STX11 was localized in the cation-dependent mannose-6-phosphate receptor (CD-M6PR)-containing compartment, which was clearly distinct from cytotoxic granules or Rab27a-expressing vesicles. These subcellular structures appeared to fuse at the contact area with NK-sensitive target cells as demonstrated by partial colocalization of STX11 with perforin and Rab27a. Although STX11-deficent allo-specific cytotoxic T-lymphocytes efficiently lysed target cells and released cytotoxic granules, they exhibited a significantly lower extent of spontaneous association of perforin with Rab27a as compared with STX11-expressing T cells. Thus, our results suggest that STX11 promotes the fusion of Rab27a-expressing vesicles with cytotoxic granules and reveal an additional level of complexity in the spatial/temporal segregation of subcellular structures participating in the process of granule-mediated cytotoxicity.


Assuntos
Grânulos Citoplasmáticos/metabolismo , Sinapses Imunológicas/imunologia , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Proteínas Qa-SNARE/metabolismo , Linhagem Celular , Humanos , Linfo-Histiocitose Hemofagocítica/genética , Linfo-Histiocitose Hemofagocítica/fisiopatologia , Perforina/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Qa-SNARE/genética , Frações Subcelulares/metabolismo , Linfócitos T Citotóxicos/imunologia , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab27 de Ligação ao GTP
13.
J Mol Biol ; 395(5): 1102-13, 2010 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-19962991

RESUMO

Linear DNAs of any sequence can be packaged into empty viral procapsids by the phage T4 terminase with high efficiency in vitro. Packaging substrates of 5 kbp and 50 kbp, terminated by energy transfer dye pairs, were constructed from plasmid and lambda phage DNAs. Nuclease and fluorescence correlation spectroscopy (FCS) assays showed that approximately 20% of the substrate DNA was packaged and that the DNA dye ends of the packaged DNA were protected from nuclease digestion. Upon packaging, both 5-kbp and 50-kbp DNAs produced comparable fluorescence resonance energy transfer (FRET) between Cy5 and Cy5.5 double-dye terminated DNAs. Single-molecule FRET (sm-FRET) and photobleaching analysis shows that FRET is intramolecular rather than intermolecular upon packaging of most procapsids and demonstrates that single-molecule detection allows mechanistic analysis of packaging in vitro. FRET-FCS and sm-FRET measurements are comparable and show that both the 5-kbp and the 50-kbp packaged DNA ends are held within 8-9 nm of each other, within the dimensions of the long axis of the procapsid portal. The calculated distribution of FRET distances is relatively narrow for both FRET-FCS and sm-FRET, suggesting that the two packaged DNA ends are held at the same fixed distance relative to each other in most capsids. Because one DNA end is known to be positioned for ejection through the portal, it can be inferred that both DNAs ends are held in proximity to the portal entrance and ejection channel. The analysis suggests that a DNA loop, rather than a DNA end, is translocated by the packaging motor to fill the procapsid.


Assuntos
Bacteriófago T4/fisiologia , Capsídeo/fisiologia , Empacotamento do DNA/fisiologia , DNA Viral/fisiologia , Bacteriófago T4/genética , Bacteriófago lambda/genética , Sequência de Bases , Carbocianinas , Primers do DNA/genética , DNA Viral/genética , Endodesoxirribonucleases/fisiologia , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes , Espectrometria de Fluorescência , Montagem de Vírus/fisiologia
14.
Virology ; 391(1): 44-50, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19541336

RESUMO

Bacteriophage T4 terminase packages DNA in vitro into empty small or large proheads (esps or elps). In vivo maturation of esps yields the more stable and voluminous elps required to contain the 170 kb T4 genome. Functional proheads can be assembled containing portal-GFP fusion proteins. In the absence of terminase activity these accumulated in esps in vivo, whereas wild-type portals were found in elps. By nuclease protection assay dsDNAs of lengths 0.1, 0.2, 0.5, 5, 11, 20, 40 or 170 kb were efficiently packaged into wild-type elps in vitro, but less so into esps and gp20-GFP elps; particularly with DNAs shorter than 11 kb. However, 0.1 kb substrates were equally efficiently packaged into all types of proheads as judged by fluorescence correlation spectroscopy. These data suggest the portal controls the expansion of the major capsid protein lattice during prohead maturation, and that this expansion is necessary for DNA protection but not for packaging.


Assuntos
Bacteriófago T4/fisiologia , Empacotamento do DNA , Endodesoxirribonucleases/metabolismo , Proteínas Virais/metabolismo , Proteínas do Capsídeo/metabolismo , DNA Viral/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Montagem de Vírus
15.
J Cell Biochem ; 105(1): 136-46, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18465785

RESUMO

In flowering plants, pollen formation depends on the differentiation and interaction of two cell types in the anther: the reproductive cells, called microsporocytes, and somatic cells that form the tapetum. Previously, we cloned a pollen specific gene, zm401, from a cDNA library generated from the mature pollen of Zea mays. Expression of partial cDNA of zm401 in maize and ectopic expression of zm401 in tobacco suggested it may play a role in anther development. Here we present the expression and functional characterization of this pollen specific gene in maize. Zm401 is expressed primarily in the anthers (tapetal cells as well as microspores) in a developmentally regulated manner. That is, it is expressed from floret forming stage, increasing in concentration up to mature pollen. Knockdown of zm401 significantly affected the expression of ZmMADS2, MZm3-3, and ZmC5, critical genes for pollen development; led to aberrant development of the microspore and tapetum, and finally male-sterility. Zm401 possesses highly conserved sequences and evolutionary conserved stable RNA secondary structure in monocotyledon. These data show that zm401 could be one of the key growth regulators in anther development, and functions as a short-open reading-frame mRNA (sORF mRNA) and/or noncoding RNA (ncRNA).


Assuntos
Flores/crescimento & desenvolvimento , Flores/metabolismo , Fases de Leitura Aberta/genética , RNA não Traduzido/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Flores/genética , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , RNA Mensageiro/genética , Zea mays/genética
16.
Zhonghua Nan Ke Xue ; 9(2): 122-3, 2003 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12749133

RESUMO

OBJECTIVES: To study the effect of cryopreservative period on the cryosurvival of human spermatozoa and find out the optimal recovery time of cryopreservation. METHODS: Eighty-eight semen samples were collected from normal donors and divided randomly into 5 groups according to the period of cryopreservative storage (1 d, 7 d, 30 d, 180 d, 300 d) in liquid nitrogen after being frozen by the programized, three-step freezing method. Fresh and frozen-thawed semen were examined by the routine analysis of semen and then the sperm recovery rate were calculated. RESULTS: There were no significant differences in sperm recovery rate between group I and the others (P > 0.05). The period of cryopreservative storage in liquid nitrogen had no correlation with the cryosurvival of human spermatozoa (r = 0.05, P > 0.05). CONCLUSIONS: It was indicated that freezing-thawing after 24 h would be helpful to the screening of semen donors in batches for donor insemination of human sperm bank.


Assuntos
Criopreservação , Preservação do Sêmen , Espermatozoides/fisiologia , Humanos , Masculino , Bancos de Esperma , Fatores de Tempo
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