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1.
Biosens Bioelectron ; 141: 111452, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31252259

RESUMO

A stable and sensitive electrochemical acetylcholinesterase (AChE) biosensor for detection of organophosphorus pesticides (OPs) was developed by doping Au nanorods (AuNRs)@mesoporous SiO2 (MS) core-shell nanoparticles into CS/TiO2-CS (CS denotes for chitosan) immobilization matrix. AuNRs@MS core-shell nanoparticles were synthesized and characterized. The doping and the biosensor fabrication process were probed and confirmed by scanning electron microscopy and electrochemistry techniques. The doping conditions were optimized. The matrix both before and after AChE immobilization had a mesoporous nanostructure. The nanoparticles dispersed homogeneously within the matrix. The doping significantly enhanced the electro-conductivity of the TiO2-CS hydrogel, and dramatically improved the bioelectrocatalytic activity and OPs detection sensitivity of the AChE immobilized matrix. The detection linear ranges for both dichlovos (DDVP) and fenthion were from 0.018 µM (4.0 ppb) to 13.6 µM, and the limit of detection (LOD) was 5.3 nM (1.2 ppb) and 1.3 nM (0.36 ppb), respectively. The biosensor exhibited high reproducibility and accuracy in detecting OPs spiked vegetable juice samples. In addition, it exhibited very high detection stability and storage stability. The developed AChE biosensor was provided to be a promisingly applicable tool for OPs detection with high reliability, simplicity, and rapidness.


Assuntos
Técnicas Biossensoriais/métodos , Ouro/química , Hidrogéis/química , Nanotubos/química , Compostos Organofosforados/análise , Praguicidas/análise , Acetilcolinesterase/química , Animais , Quitosana/química , Electrophorus , Enzimas Imobilizadas/química , Proteínas de Peixes/química , Limite de Detecção , Nanopartículas/química , Dióxido de Silício/química , Titânio/química
2.
Zhonghua Nan Ke Xue ; 24(2): 147-151, 2018 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30156075

RESUMO

OBJECTIVE: To investigate the prevalence of Ureaplasma urealyticum (UU) infection in infertile men, its influence on routine semen parameters and the distribution of antisperm antibody (AsAb) and its types in infertile patients with UU infection. METHODS: We detected the positive rate of UU infection, semen parameters, and the distribution of AsAb and its types in 662 infertile men and 25 normal fertile male controls followed by comparison of the obtained data between the two groups of subjects. RESULTS: The positive rate of UU infection was significantly higher in the infertile men than in the normal controls (52.87% ï¼»350/662ï¼½ vs 16.00% ï¼»4/25ï¼½, χ2 = 11.68, P <0.05). The semen volume, sperm count, sperm concentration and percentage of progressively motile sperm were remarkably lower in the UU-positive infertile males than in the control group (P <0.05). No statistically significant difference was observed between the UU-positive and UU-negative groups in the positive rates of total AsAb (43.4% vs 36.5%, χ2 = 3.25, P >0.05) and AsAb IgA, IgM and IgG in the seminal plasma, or in the percentages of serum AsAb IgM (16.9% vs 20.5%, χ2 = 1.22, P >0.05) and IgG (32.7% vs 28.9%, χ2 = 0.99, P >0.05) except in that of serum AsAb IgA (23.6% vs 17.0%, χ2 = 4.03, P <0.05). CONCLUSIONS: The UU infection rate is high in infertile males, which decreases the semen volume, total sperm count, motile sperm concentration and percentage of progressively motile sperm and increases the positive rate of serum AsAb IgA.


Assuntos
Anticorpos Antibacterianos/análise , Infertilidade Masculina/microbiologia , Espermatozoides/imunologia , Infecções por Ureaplasma/diagnóstico , Ureaplasma urealyticum/imunologia , Humanos , Infertilidade Masculina/imunologia , Masculino , Sêmen , Contagem de Espermatozoides , Infecções por Ureaplasma/imunologia
3.
Zhonghua Nan Ke Xue ; 23(4): 329-336, 2017 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29714418

RESUMO

OBJECTIVE: Sperm DNA fragmentation (SDF) is widely used to predict male infertility and the methods of detecting SDF are varied. This study aimed to compare two methods of SDF detection and investigate the correlation between SDF and sperm quality. METHODS: Using sperm chromatin structure assay (SCSA) and sperm chromatin dispersion test (SCD), we detected SDF in 108 semen samples collected in the Center of Reproduction and Genetics of Suzhou Municipal Hospital. We compared the results of the two methods and analyzed the correlations of SDF routine semen parameters, sperm morphology and the age of the patients. RESULTS: A significant consistency was found in the SDF index (DFI) between the two methods (P<0.01). The DFI was correlated negatively with sperm motility, the percentage of progressively motile sperm, and that of morphologically normal sperm (P <0.01), but positively with the teratozoospermia index (P <0.01 in SCSA and P <0.05 in SCD). The DFI measured by SCSA showed a significantly positive correlation with the patients' age (P <0.01), but not that obtained by SCD. CONCLUSIONS: The results of both SCSA and SCD play an important role in predicting sperm quality. As a clinical index, the DFI has a predictive value for male infertility. However, the results of different detecting methods vary widely, which calls for further studies on their standardization.


Assuntos
Cromatina/fisiologia , Fragmentação do DNA , Infertilidade Masculina/diagnóstico , Sêmen/fisiologia , Espermatozoides/fisiologia , Cromatina/genética , Humanos , Masculino , Análise do Sêmen , Motilidade dos Espermatozoides , Espermatozoides/ultraestrutura
4.
Zhonghua Nan Ke Xue ; 20(8): 690-6, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25195363

RESUMO

OBJECTIVE: To study the application value of normal sperm morphology on the outcomes of classic in vitro fertilization and embryo transfer (IVF-ET). METHODS: This study included 659 infertile couples admitted to our center for IVF-ET. Based on the percentage of morphologically normal sperm (MNS), we divided the patients into groups A (n = 112, MNS < 2%), B (n = 180, MNS > or = 2 - < 4%), C (n = 74, MNS > or = 4 - < 5%), and D (n = 293, MNS > or = 5%), and compared the rates of fertilization, normal fertilization, embryos obtained, biochemical pregnancy, clinical pregnancy, implantation, and live birth among different groups. RESULTS: The mean fertilization rate was significantly higher in groups C (71.90%) and D (72.89%) than in A (57.97%) and B (63.29%) (P < 0.05), with no remarkable differences either between A and B (P > 0.05) or between C and D (P > 0.05). The normal fertilization rate was also significantly higher in group D (57.16%) than in A (46.52%) and B (50.89%) (both P < 0.05) as well as in C (54.67%) than in A (P < 0.05). The rate of embryos obtained, too, was markedly higher in group D (55.62%) than in B (45.75%) (P < 0.05), but none with remarkable difference from other groups (all P > 0.05). There were no statistically significant differences among the four groups in the rates of biochemical pregnancy, clinical pregnancy, implantation, abortion, and live birth (all P > 0.05). CONCLUSION: The rate of MNS had some influence on IVF-ET, and 5% MNS exhibited a higher value than 4% MNS in predicting the outcomes of IVF.


Assuntos
Implantação do Embrião , Fertilização in vitro , Espermatozoides/citologia , Adulto , Feminino , Humanos , Masculino , Gravidez , Resultado da Gravidez , Estudos Retrospectivos
5.
Food Chem Toxicol ; 50(10): 3521-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22828241

RESUMO

Selenium (Se) is an essential trance element in testis. However, the potential protective effects of Se against cadmium (Cd)-induced reproductive toxicity remained to be elucidated. Male ICR mice were orally administered by gavage with Na2SeO3 (0.1, 0.2, 0.4 mg/kg BW) for 1h prior to CdCl2 (5 mg/kg BW) alone or in combination for 15, 25 or 35 days. Cd exposure caused a significant decrease in body weight, sperm concentration and motility as well as plasma testosterone level which was accompanied by decreased antioxidant enzymatic activity of SOD and GSH-Px and by increased lipid peroxidation (as malondialdehyde, MDA). Se pretreatment compensated deficits in the sperm parameters (concentration, motility and morphology) induced by Cd. Se (0.4 mg/kg BW) treatment significantly increased serum testosterone level that was reduced by Cd (on 15th, 25th and 35th day) (P<0.01). Se treatment ameliorated Cd-induced reduction in testicular steroidogenic acute regulatory (StAR) and 17ß-hydroxysteroid dehydrogenase (17ß-HSD) activities. The present study suggest that the protective potential of Se against Cd-induced reprotoxicity might be due to up-regulation StAR and testosterone synthetic enzyme activity, which could be useful for increasing testosterone synthesis for achieving optimum protection in sperm quality and spermatogenesis.


Assuntos
Cádmio/toxicidade , Selênio/farmacologia , Espermatogênese/efeitos dos fármacos , Testosterona/biossíntese , Animais , Antioxidantes/metabolismo , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Poluentes Ambientais/toxicidade , Regulação da Expressão Gênica , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Tamanho do Órgão , Selênio/administração & dosagem , Motilidade dos Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Superóxido Dismutase/metabolismo , Testículo/efeitos dos fármacos , Testículo/patologia , Testículo/fisiologia
6.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): o322, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22346956

RESUMO

In the title mol-ecule, C(11)H(11)N(3)O(2), the dihedral angle between the benzene and triazole rings is 76.47 (10)°. The crystal structure exhibits inter-molecular O-H⋯N hydrogen bonds, which lead to the formation of helical chains along [001].

7.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): o3001, 2010 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-21589162

RESUMO

The title compound, C(8)H(11)N(3)O(4)·H(2)O, was synthesized by reaction of 2-azido-acetic acid and ethyl acetyl-acetate. In the crystal packing, mol-ecules are linked by strong inter-molecular O-H⋯N and O-H⋯O hydrogen bonds into double layers parallel to the ab plane.

8.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): o3077, 2010 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-21589386

RESUMO

In the title compound, C(12)H(12)N(2), the dihedral angle between the benzene and pyridine rings is 67.63 (8)°. Mol-ecules are linked into centrosymmetric dimers by a simple inter-molecular N-H⋯N hydrogen bond with graph-set motif R(2) (2)(8).

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