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1.
Phys Chem Chem Phys ; 26(11): 8623-8630, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38426271

RESUMO

Using first-principles calculations and micro-magnetic simulations, we investigate the electronic structures, the effect of biaxial strain on the topological characteristics, magnetic anisotropy energy (MAE), Dzyaloshinskii-Moriya interaction (DMI) and spin textures in the Janus 1T phase VTeCl (1T-VTeCl) monolayer. Our results show that 1T-VTeCl has an intrinsic edge state, and a topological phase transition with a sizeable band gap is achieved by applying biaxial strain. Interestingly, the MAE can be switched from the in-plane to the off-plane with a compressive strain of -5%. Microscopically, the origin of MAE is mainly associated with the large spin-orbit coupling (SOC) from the heavy nonmagnetic Te atoms rather than that from the V atoms. Furthermore, the induced DMI (0.09 meV) can occur stabilizing magnetic merons without applying temperatures and magnetic fields. Then, the skyrmions, frustrated antiferromagnetism and vortex are induced after applying a suitable compressive strain. Our study provides compelling evidence that the 1T-VTeCl monolayer with topological properties holds great potential for application in spintronic devices, as well as information storage devices based on different magnetic phases achievable through strain engineering.

2.
Ecotoxicol Environ Saf ; 273: 116166, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38430577

RESUMO

Nanotechnology is one of the most recent approaches employed to defend plants against both biotic and abiotic stress including heavy metals such as Cadmium (Cd). In this study, we evaluated the effects of titanium dioxide (TiO2) nanoparticles (TiO2 NPs) in alleviating Cd stress in Tetrastigma hemsleyanum Diels et Gilg. Compared with Cd treatment, TiO2 NPs decreased leaf Cd concentration, restored Cd exposure-related reduction in the biomass to about 69% of control and decreased activities of antioxidative enzymes. Integrative analysis of transcriptome and metabolome revealed 325 differentially expressed genes associated with TiO2 NP treatment, most of which were enriched in biosynthesis of secondary metabolites. Among them, the flavonoid and phenylpropanoid biosynthetic pathways were significantly regulated to improve the growth of T. hemsleyanum when treated with Cd. In the KEGG Markup Language (KGML) network analysis, we found some commonly regulated pathways between Cd and Cd+TiO2 NP treatment, including phenylpropanoid biosynthesis, ABC transporters, and isoflavonoid biosynthesis, indicating their potential core network positions in controlling T. hemsleyanum response to Cd stress. Overall, our findings revealed a complex response system for tolerating Cd, encompassing the transportation, reactive oxygen species scavenging, regulation of gene expression, and metabolite accumulation in T. hemsleyanum. Our results indicate that TiO2 NP can be used to reduce Cd toxicity in T. hemsleyanum.


Assuntos
Antioxidantes , Nanopartículas , Cádmio/toxicidade , Titânio/farmacologia
3.
Int J Mol Sci ; 24(22)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-38003663

RESUMO

Transcription factor IIB (TFIIB) is a general transcription factor for RNA polymerase II, exerting its influence across various biological contexts. In the majority of eukaryotes, TFIIB typically has two homologs, serving as general transcription factors for RNA polymerase I and III. In plants, however, the TFIIB-related protein family has expanded greatly, with 14 and 9 members in Arabidopsis and rice, respectively. BRP5/pollen-expressed transcription factor 2 (PTF2) proteins belong to a subfamily of TFIIB-related proteins found only in plants and algae. The prior analysis of an Arabidopsis atbrp5 mutant, characterized by a T-DNA insertion at the 5' untranslated region, demonstrated the essential role of BRP5/PTF2 during the process of pollen germination and embryogenesis in Arabidopsis. Using a rice transformation system based on CRISPR/Cas9 technology, we have generated transgenic rice plants containing loss-of-function frameshift mutations in the BRP5/PTF2 gene. Unlike in the Arabidopsis atbrp5 mutant, the brp5/ptf2 frameshift mutations were not transmitted to progeny in rice, indicating an essential role of BRP5/PTF2 in both male and female gamete development or viability. The silencing of rice BRP5/PTF2 expression through RNA interference (RNAi) had little effect on vegetative growth and panicle formation but strongly affected pollen development and grain formation. Genetic analysis revealed that strong RNAi silencing of rice BRP5/PTF2 was still transmissible to progeny almost exclusively through female gametes, as found in the Arabidopsis atbrp5 knockdown mutant. Thus, reduced rice BRP5/PTF2 expression impacted pollen preferentially by interfering with male gamete development or viability. Drawing upon these findings, we posit that BRP5/PTF2 assumes a distinct and imperative function in the realm of plant sexual reproduction.


Assuntos
Oryza , Proteínas de Plantas , Fator de Transcrição TFIIB , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Gametogênese , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/metabolismo , Plantas/metabolismo , Pólen/metabolismo , Fator de Transcrição TFIIB/metabolismo , Proteínas de Plantas/metabolismo
4.
Int J Mol Sci ; 22(21)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34769103

RESUMO

Salicylic acid (SA) is an important plant hormone with a critical role in plant defense against pathogen infection. Despite extensive research over the past 30 year or so, SA biosynthesis and its complex roles in plant defense are still not fully understood. Even though earlier biochemical studies suggested that plants synthesize SA from cinnamate produced by phenylalanine ammonia lyase (PAL), genetic analysis has indicated that in Arabidopsis, the bulk of SA is synthesized from isochorismate (IC) produced by IC synthase (ICS). Recent studies have further established the enzymes responsible for the conversion of IC to SA in Arabidopsis. However, it remains unclear whether other plants also rely on the ICS pathway for SA biosynthesis. SA induces defense genes against biotrophic pathogens, but represses genes involved in growth for balancing defense and growth to a great extent through crosstalk with the growth-promoting plant hormone auxin. Important progress has been made recently in understanding how SA attenuates plant growth by regulating the biosynthesis, transport, and signaling of auxin. In this review, we summarize recent progress in the biosynthesis and the broad roles of SA in regulating plant growth during defense responses. Further understanding of SA production and its regulation of both defense and growth will be critical for developing better knowledge to improve the disease resistance and fitness of crops.


Assuntos
Desenvolvimento Vegetal , Plantas/metabolismo , Ácido Salicílico/metabolismo , Estresse Fisiológico , Ácidos Indolacéticos/metabolismo , Imunidade Vegetal , Receptor Cross-Talk
5.
BMC Genomics ; 20(1): 891, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752676

RESUMO

BACKGROUND: Barley yellow dwarf (BYD) is an important virus disease that causes significant reductions in wheat yield. For effective control of Barley yellow dwarf virus through breeding, the identification of genetic sources of resistance is key to success. In this study, 335 geographically diverse wheat accessions genotyped using an Illumina iSelect 90 K single nucleotide polymorphisms (SNPs) bead chip array were used to identify new sources of resistance to BYD in different environments. RESULTS: A genome-wide association study (GWAS) performed using all the generalised and mixed linkage models (GLM and MLM, respectively) identified a total of 36 significant marker-trait associations, four of which were consistently detected in the K model. These four novel quantitative trait loci (QTL) were identified on chromosomes 2A, 2B, 6A and 7A and associated with markers IWA3520, IWB24938, WB69770 and IWB57703, respectively. These four QTL showed an additive effect with the average visual symptom score of the lines containing resistance alleles of all four QTL being much lower than those with less favorable alleles. Several Chinese landraces, such as H-205 (Baimazha) and H-014 (Dahongmai) which have all four favorable alleles, showed consistently higher resistance in different field trials. None of them contained the previously described Bdv2, Bdv3 or Bdv4 genes for BYD resistance. CONCLUSIONS: This study identified multiple novel QTL for BYD resistance and some resistant wheat genotypes. These will be useful for breeders to generate combinations with and/or without Bdv2 to achieve higher levels and more stable BYD resistance.


Assuntos
Resistência à Doença/genética , Luteovirus , Doenças das Plantas/genética , Doenças das Plantas/virologia , Triticum/genética , Triticum/virologia , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas
6.
Theor Appl Genet ; 130(8): 1559-1568, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28447117

RESUMO

KEY MESSAGE: We report the first study on the unique allele from wild barley that can improve waterlogging tolerance in cultivated barley with a substantially higher contribution to aerenchyma formation. Waterlogging is one of the major abiotic stresses that dramatically reduce barley crop yield. Direct selection on waterlogging tolerance in the field is less effective due to its viability to environment. The most effective way of selection is to choose traits that make significant contributions to the overall tolerance and are easy to score. Aerenchyma formation under waterlogging stress is one of the most effective mechanisms to provide adequate oxygen supply and overcome stress-induced hypoxia imposed on plants. In this study, a new allele for aerenchyma formation was identified from a wild barley accession TAM407227 on chromosome 4H. Compared to that identified in cultivated barley, this allele not only produced a greater proportion of aerenchyma but made a greater contribution to the overall waterlogging tolerance. The QTL explained 76.8% of phenotypic variance in aerenchyma formation with a LOD value of 51.4. Markers co-segregating with the trait were identified and can be effectively used in marker assisted selection.


Assuntos
Inundações , Hordeum/genética , Locos de Características Quantitativas , Estresse Fisiológico , Alelos , Mapeamento Cromossômico , Ligação Genética , Marcadores Genéticos , Hordeum/fisiologia , Fenótipo , Água/fisiologia
7.
Biol Reprod ; 92(2): 38, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25505202

RESUMO

Recent studies on the eNOS gene and male infertility show that expression of eNOS regulates normal spermatogenesis in the testis, and the eNOS gene variants (T-786C, 4a4b, and G894T) are potentially involved in impairment of spermatogenesis and sperm function. Thus, we conducted this association and meta-analysis study to further validate whether variants of those three loci affected the risk of idiopathic asthenozoospermia (AZS) and male infertility. Approximately 340 Chinese idiopathic AZS patients and 342 healthy men were included for this case-control study, genotyped by gel electrophoresis analysis or direct sequencing of PCR products. The eNOS mRNA isolated from the semen of patients was further examined by quantitative real-time PCR. Also, a meta-analysis of association between eNOS gene polymorphisms and male infertility was performed. A significant association was identified on allelic level between 4a4b variant and AZS in our study (chi-squared = 7.53, corrected P = 0.018, odds ratio (OR) = 1.808), while there were no significant difference of T-786C and G894T for asthenozoospermia in both genotype and allele distributions. In addition, expression of eNOS was up-regulated in patients compared with controls (about 2.4-fold, P < 0.001). Furthermore, the results of the meta-analysis support the conclusion that the T-786C and 4a4b loci were associated with male infertility in both Asian and Caucasian populations. Our study provides genetic evidence for the eNOS gene being a risk factor for idiopathic AZS and male infertility. Considering genetic differences among populations and complex pathogenesis of male infertility, more validating studies using independent samples are suggested in the future.


Assuntos
Astenozoospermia/genética , Predisposição Genética para Doença , Infertilidade Masculina/genética , Óxido Nítrico Sintase Tipo III/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Estudos de Casos e Controles , Frequência do Gene , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
8.
Biol Reprod ; 90(5): 96, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24648396

RESUMO

A previous genomewide association study of nonobstructive azoospermia (NOA) in the Han Chinese population identified three risk loci (rs12097821, rs2477686, and rs10842262) and provided strong evidence for a genetic influence in male infertility. However, recently, a follow-up study of these single nucleotide polymorphism (SNP) loci in the Japanese population showed that none of them were significantly associated with NOA. Therefore, we conducted an association study, consisting of 550 NOA cases and 555 normal controls, to further validate whether the risk of those three SNPs still existed in an independent Han Chinese male population. The association studies did not support the association of rs12097821 and rs2477686 with NOA for both genotype and allele distributions, but rs10842262 in the SOX5 gene was significantly associated with NOA (chi square = 9.31; P = 0.0095 and chi square = 9.27; P = 0.0023, respectively). Our study provides genetic evidence for SOX5 polymorphism in NOA, contributing to predicting males at high risk of NOA in Han Chinese population. Considering genetic differences among populations, future validating studies in independent samples are suggested.


Assuntos
Povo Asiático/genética , Azoospermia/genética , Infertilidade Masculina/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único/genética , Proteína-Arginina N-Metiltransferases/genética , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Transcrição SOXD/genética , Adulto , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , DNA/química , DNA/genética , Seguimentos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Peroxinas , Reação em Cadeia da Polimerase , Adulto Jovem
9.
Zhonghua Nan Ke Xue ; 20(1): 30-6, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-24527534

RESUMO

OBJECTIVE: To investigate sperm function indexes that can be used to effectively evaluate the sperm donors' fertility so as to select healthy post-thaw semen samples and improve the success rate of assisted reproductive technology. METHODS: According to the pregnancy outcomes, we divided 40 donor semen samples into a high-fertility group (n = 20) and a low-fertility group (n = 20). We measured and compared the concentration, progressive motility, morphology, acrosome intactness, DNA integrity and mitochondrial membrane potential (MMP) of the post-thaw sperm between the two groups. RESULTS: There were statistically significant differences between the high- and low-fertility groups in the percentages of morphologically normal sperm ([18.50 +/- 6.10]% vs [14.42 +/- 6.44]%, P < 0.01), acrosome intactness ([86.17 +/- 4.49]% vs [80.04 +/- 7.52]%, P < 0.05) and DNA fragmentation index ([9.21 +/- 3.22]% vs [15.72 +/- 8.20]%, P < 0.05), but not in MMP ([56.75 +/- 18.80]% vs [52.23 +/- 18.86]%, P > 0.05). A significantly positive correlation was found between MMP and sperm motility (r = 0.760, P < 0.05), but not between other sperm functions and sperm concentration and motility. CONCLUSION: Sperm concentration, motility, morphology, acrosome intactness rate and DNA integrity contribute effectively to the evaluation of the fertilization capacity of post-thaw donor semen samples.


Assuntos
Criopreservação , Fertilização , Preservação do Sêmen , Espermatozoides/fisiologia , Adulto , Feminino , Humanos , Masculino , Gravidez , Bancos de Esperma , Contagem de Espermatozoides , Motilidade dos Espermatozoides
10.
Dev Biol ; 369(2): 308-18, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22819676

RESUMO

It is generally thought that vertebral patterning and identity are globally determined prior to somite formation. Relatively little is known about the regulators of vertebral specification after somite segmentation. Here, we demonstrated that Ndrg2, a tumor suppressor gene, was dynamically expressed in the presomitic mesoderm (PSM) and at early stage of differentiating somites. Loss of Ndrg2 in mice resulted in vertebral homeotic transformations in thoracic/lumbar and lumbar/sacral transitional regions in a dose-dependent manner. Interestingly, the inactivation of Ndrg2 in osteoblasts or chondrocytes caused defects resembling those observed in Ndrg2(-/-) mice, with a lower penetrance. In addition, forced overexpression of Ndrg2 in osteoblasts or chondrocytes also conferred vertebral defects, which were distinct from those in Ndrg2(-/-) mice. These genetic analyses revealed that Ndrg2 modulates vertebral identity in segmented somites rather than in the PSM. At the molecular level, combinatory alterations of the amount of Hoxc8-11 gene transcripts were detected in the differentiating somites of Ndrg2(-/-) embryos, which may partially account for the vertebral defects in Ndrg2 mutants. Nevertheless, Bmp/Smad signaling activity was elevated in the differentiating somites of Ndrg2(-/-) embryos. Collectively, our findings unveiled Ndrg2 as a novel regulator of vertebral specification in differentiating somites.


Assuntos
Proteínas/metabolismo , Somitos/embriologia , Somitos/metabolismo , Coluna Vertebral/embriologia , Coluna Vertebral/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Sequência de Bases , Padronização Corporal/genética , Padronização Corporal/fisiologia , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Primers do DNA/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Marcação de Genes , Genes Homeobox , Mesoderma/embriologia , Mesoderma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes , Camundongos Transgênicos , Gravidez , Proteínas/genética , Transdução de Sinais , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
11.
Zhonghua Nan Ke Xue ; 19(10): 886-9, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24218940

RESUMO

OBJECTIVE: To investigate the effect of pre-freezing equilibration on the cryo-survival of human sperm and to optimize the protocol of direct fumigation for the freeze-thawing of human sperm. METHODS: We collected 50 semen samples from healthy donors, each subjected to cryopreservation with 3 different methods: non-equilibration freezing (Group A), 10-min equilibration at room temperature before freezing (Group B), and 10-min equilibration at 4 degrees C before freezing (Group C). We examined all the post-thaw semen samples by computer-assisted semen analysis for the sperm motility parameters, and detected the sperm vitality and deformity index (SDI). RESULTS: The recovery rate of progressive sperm motility was (61.88 +/- 16.94)% in Group C, remarkably higher than in A ([48.61 +/- 16.44]%) and B ([49.41 +/- 13.77]%) (P < 0.05), but with no significant difference between the latter two. And there were no significant differences in sperm vitality and SDI among the three groups. CONCLUSION: Ten-minute equilibration at 4 degrees C before freezing can evidently improve the progressive motility of sperm in addition to its advantages of easy operation and controllable experimental condition.


Assuntos
Criopreservação/métodos , Análise do Sêmen , Preservação do Sêmen/métodos , Adulto , Humanos , Masculino , Bancos de Esperma , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Adulto Jovem
12.
Front Microbiol ; 14: 1292896, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38163074

RESUMO

Tetrastigma hemsleyanum Diels et Gilg, commonly known as Sanyeqing (SYQ), is an important traditional Chinese medicine. The content of bioactive constituents varies in different cultivars of SYQ. In the plant growth related researches, rhizosphere microbiome has gained significant attention. However, the role of bacterial communities in the accumulation of metabolites in plants have not been investigated. Herein, the composition of bacterial communities in the rhizosphere soils and the metabolites profile of different SYQ cultivars' roots were analyzed. It was found that the composition of microbial communities varied in the rhizosphere soils of different SYQ cultivars. The high abundance of Actinomadura, Streptomyces and other bacteria was found to be associated with the metabolites profile of SYQ roots. The findings suggest that the upregulation of rutin and hesperetin may contribute to the high bioactive constituent in SYQ roots. These results provide better understanding of the metabolite accumulation pattern in SYQ, and also provide a solution for enhancing the quality of SYQ by application of suitable microbial consortia.

13.
Micromachines (Basel) ; 15(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38276829

RESUMO

Telluriums (Te) with various nanostructures, including particles, wires, and sheets, are controllably synthesized by adjusting the content of polyvinylpyrrolidone (PVP) in a facile solvothermal reaction. Te nanostructures all have complete grain sizes with excellent crystallinity and mesopore structures. Further, the formation mechanisms of Te nanostructures are proposed to be that the primary nuclei of Te are released from the reduction of TeO32- using N2H4·H2O, and then grow into various nanostructures depending on the different content of PVP. These nanostructures of Te all exhibit the photocatalytic activities for the degradation of MB and H2 production under visible light irradiation, especially Te nanosheets, which have the highest efficiencies of degradation (99.8%) and mineralization (65.5%) at 120 min. In addition, compared with pure Te nanosheets, the rate of H2 production increases from 412 to 795 µmol∙h-1∙g-1 after the introduction of Pt, which increases the output by nearly two times. The above investigations indicate that Te with various nanostructures is a potential photocatalyst in the field of degradation of organic pollutants and H2 fuel cells.

14.
Materials (Basel) ; 16(24)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38138657

RESUMO

At present, it is known that when there is clay in concrete, polycarboxylates (PCE) will preferably adsorb in the clay, so that PCE cannot be fully combined with cement particles, which reduces the workability of the cement slurry. In this paper, a new type of maltitol-ammonium salt cationic (KN-lm) sacrificial agent (SA) has been successfully developed via a simple method, which makes PCE easier to bond with cement particles in the cement slurry containing clay. The effect of KN-lm on the fluidity of clay-containing cement paste is studied, and the experimental results show that KN-lm, as an efficient SA of cement slurry, makes PCE more compatible with clay-containing cement slurry, and increases the initial fluidity of cement slurry by about 19%. Further investigations of TOC, XRD, and zeta potential measurements reveal that a KN-lm ion is only preferably adsorbed into clay compared to PCE through electrostatic adsorption but without having any crystal structure change, thus resulting in good dispersion of cement particles. The addition of KN-lm plays an important role in hindering the hydration expansion of the clay by preferential electrostatic adsorption, which means PCE cannot easily insert into the interlayer of the clay.

15.
Zhonghua Nan Ke Xue ; 18(2): 172-5, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22568218

RESUMO

Hedgehog signaling pathway plays an important role in regulating the development of endocrine glands. Desert hedgehog (Dhh) has become a recent focus for its regulation of testis development, especially of Leydig cells. Dhh, as a Sertoli cell product, regulates the proliferation and differentiation of Leydig cell lineage and functions to secrete testosterone through a paracrine signaling mechanism. Testosterone, as the most important sex hormone of the male, plays a critical role in testis development, spermatogenesis and maintenance of normal masculinization. Therefore, normal Dhh signaling pathway ensures normal spermatogenic function. Researches on the Hedgehog signaling pathway in the testis have a potential significance for studying the pathophysiological mechanisms of androgen deficiency and dyszoospermia, as well as for the clinical treatment of these diseases.


Assuntos
Proteínas Hedgehog/metabolismo , Células Intersticiais do Testículo/citologia , Transdução de Sinais , Testículo/metabolismo , Diferenciação Celular , Proliferação de Células , Humanos , Masculino , Espermatogênese , Testículo/citologia
16.
Zhonghua Nan Ke Xue ; 18(7): 606-10, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-22994045

RESUMO

OBJECTIVE: To investigate the value and clinical application of the Three-Step Sperm Retrieval method in improving the sperm retrieval rate for non-obstructive azoospermia (NOA) patients. METHODS: Seventy-three NOA patients underwent Three-Step Sperm Retrieval in the following order of procedures: testicular fine needle aspiration (TFNA), testicular sperm extraction (TSE), and microdissection testicular sperm extraction (MD-TSE). The testicular tissue obtained from each step was observed for spermatozoa under the 400-fold inverted microscope. If spermatozoa were found in one step, the operation would be stopped; otherwise, the next step would be carried out. The testicular tissue was subjected to pathological examination. RESULTS: Spermatozoa was found in the testicular tissue in 38.4% of the cases (28/73) at TFNA as the first step, in 52.1% (38/73) at TFNA and TSE, and in 64.4% (47/73) at TFNA, TSE and MD-TSE. Pathological examination showed 25 of the cases to be Sertoli cell-only syndrome, 21 to be sperm maturation arrest and the other 27 to be hypospermatogenesis, in which spermatozoa were found in 10, 14 and 23 cases, respectively. CONCLUSION: The Three-Step Sperm Retrieval method can significantly improve the sperm retrieval rate for NOA patients. And the sperm retrieval rate is associated with the pathological type of the testicular tissue, a higher rate with hypospermatogenesis.


Assuntos
Azoospermia , Recuperação Espermática , Testículo/cirurgia , Adulto , Humanos , Masculino , Testículo/patologia
17.
Zhonghua Nan Ke Xue ; 18(3): 227-30, 2012 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-22474987

RESUMO

OBJECTIVE: To study the effect of direct fumigation on the post-thaw recovery rate of cryopreserved spermatozoa, and to search for a best method for human sperm cryopreservation. METHODS: We collected semen samples from 100 donors conforming to the normal reference values in WHO Laboratory Manual for the Examination and Processing of Human Semen (5th Ed), divided them into two groups, and subjected them to cryopreservation by programmable freezing (Group A) and direct fumigation (Group B), respectively. We detected the progressive motility of pre-freezing and post-thaw sperm with a computer-assisted semen analyzer, and compared the effects of the two methods on the functional integrity of sperm membrane and the rate of abnormal sperm using the percentage of hypo-osmotic swelling sperm and modified Papanicolaou staining. RESULTS: Statistically significant differences were found in post-thaw sperm progressive motility between the Groups A and B ([34.0 +/- 18.4]% vs [43.0 +/- 19.5]%, P<0.05), both remarkably decreased as compared with pre-freezing ([57.0 +/- 16.7]%, P<0.05). Such differences were also found in the post-thaw recovery rate of progressively motile sperm between the two groups ([52.2 +/- 20.6]% vs [67.1 +/- 20.0]%, P<0.05). The post-thaw percentage of hypo-osmotic swelling sperm was obviously decreased in both Groups A and B ([67.1 +/- 11.1]% and [70.6 +/- 10.0]%) in comparison with pre-freezing ([84.5 +/- 7.5]%, P<0.05), with significant differences between A and B (P<0.05). However, the rate of sperm abnormality was evidently increased in Groups A and B ([85.0 +/- 8.7% and [85.7 +/- 9.1]%), significantly higher than pre-freezing ([77.8 +/- 9.6]%, P<0.05), but with no significant differences between A and B (P>0.05). CONCLUSION: Direct fumigation is superior to programmable freezing for its easier operation, wider application, and higher sperm recovery rate.


Assuntos
Criopreservação/métodos , Preservação do Sêmen/métodos , Espermatozoides , Adulto , Humanos , Masculino , Análise do Sêmen , Motilidade dos Espermatozoides , Adulto Jovem
18.
Zhonghua Nan Ke Xue ; 18(5): 400-3, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22741435

RESUMO

OBJECTIVE: To analyze the distribution characteristics of the main semen parameters of healthy semen donors and normal fertile men in Shanghai, compare the semen quality between the two groups, and investigate the normal reference values of the semen parameters of the fertile population in Shanghai. METHODS: We obtained semen samples from 100 healthy donors and 41 fertile men, performed semen analyses according to the WHO (2010) guidelines, and determined the semen volume, sperm concentration, sperm progressive motility, total sperm count and total progressively motile sperm count. We analyzed the distribution of the semen parameters of the normal fertile men, and obtained the lower limits of their normal reference values. RESULTS: There were no statistically significant differences in the main semen parameters between the healthy donors and normal fertile men (P < 0.05). The lower reference limits for the semen parameters of normal fertile men in Shanghai (P < 0.05) were as follows: sperm concentration > or = 27.3 x 10(6)/ml, sperm progressive motility > or = 8.1%, semen volume > or = 0.82 ml, total sperm count > or = 44.73 x 10(6) per ejaculate, and total progressively motile sperm count > or = 24.68 x 10(6) per ejaculate. CONCLUSION: For the evaluation of male fecundity, total sperm count and total progressively motile sperm count may be two better predictors than others.


Assuntos
Análise do Sêmen , Sêmen , Espermatozoides , Adulto , China , Fertilidade , Humanos , Masculino , Valores de Referência , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Doadores de Tecidos , Adulto Jovem
19.
Medicine (Baltimore) ; 101(52): e32604, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36596069

RESUMO

As one of the knee preservation surgical approaches, good clinical outcomes of high tibial osteotomy were reported. Aims of this study were to analyze the clinical outcome and pre- and postoperative radiographical parameter and knee functional score between distal tibial tubercle high tibial osteotomy (DTTHTO) and open wedge- high tibial osteotomy (OWHTO) in patients with varus knee osteoarthritis after more than 1 year following-up. A total of 194 consecutive patients in our joint center from March 2016 to October 2021 were enrolled, according to the surgical method, patients were divided into DDTHTO and OWHTO groups. Radiographic parameters of Kellgren-Lawrence grading, hip-knee-ankle angle, weight bearing line ratio and medial tibial plateau angle, knee functional score of American knee society (AKS) score, western Ontario and McMaster universities arthritis index (WOMAC) score, visual analogue score (VAS) were introduced to evaluate clinical outcome for patients who received DDTHTO and OWHTO. There were 103 knees and 89 knees in the OWHTO and DTTHTO group, respectively. Mean weight bearing line ratio for OWHTO and DTTHTO were 25.1 ±â€…11.7 and 25.2 ±â€…12.0% respectively, medial tibial plateau angle and hip-knee-ankle angle angle demonstrated that all patients in the present study inherited a varus angle ranges from 3.4° to 9.5°. Preoperative AKS, WOMAC and VAS were 68.4 ±â€…5.7 versus 69.0 ±â€…5.9, 109.3 ±â€…15.0 versus 107.7 ±â€…14.0 and 6.8 ±â€…1.0 versus 6.9 ±â€…0.8, and there was no significant difference between 2 groups (P > .05). Mean postoperative AKS and WOMAC score for patients in both OWHTO and DTTHTO group were significantly improved, moreover, postoperative VAS of DTTHTO patients was lower than that in OWHTO group (P < .05). When comparing the operation time, intraoperative blood loss and bone union time, DHHTO group shows a superiority in these variables over patients in OWHTO (121 ±â€…29.6 vs 145.7 ±â€…35.2 minutes, 115.0 ±â€…20.8 vs 103.3 ±â€…17.3 mL, 13.7 ±â€…4.1 vs 12.0 ±â€…2.8 weeks; P < .005) and incidence of complication was lower for DTTHTO group. DTTHTO in patients with varus knee osteoarthritis has good clinical outcomes, and it can achieve a better postoperative alignment. Operation time and surgical trauma were also less in patients who underwent DTTHTO.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/cirurgia , Articulação do Joelho/cirurgia , Estudos Retrospectivos , Extremidade Inferior , Tíbia/cirurgia , Osteotomia/métodos
20.
Zhonghua Nan Ke Xue ; 17(4): 356-60, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21548216

RESUMO

male gametes play a critical role in transmitting hereditary information to the offspring. Gametogenesis, especially spermatogenesis, is a complicated differentiation process including mitosis and meiosis. However, for lack of an efficient and reproducible model, the mechanism of male germ development is not yet clear. Researches on stem cells'differentiation into male gametes in vitro will promote the study of germ cell development and even reproductive biology. This article updates the researches on the culture of primordial germ cells and stem cells' differentiation into male gametes.


Assuntos
Diferenciação Celular , Células Germinativas/citologia , Células-Tronco/citologia , Técnicas de Cultura de Células , Humanos , Masculino
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