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1.
J Biomed Mater Res B Appl Biomater ; 110(6): 1391-1399, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35080336

RESUMO

The sperm selection stage is what assisted reproductive technologies have in common and is crucial as it affects the success of the treatment cycle. The employment of microfluidic platforms for sperm selection has emerged showing promising results. In microfluidic platforms, sperm cells encounter micro-confined environments meanwhile having contact with channel walls and surfaces. Modification of contact surfaces using nanoparticles leads to the alteration of surface characteristics which in turn affects sperm behavior especially motility which is an indicator for sperm health. In this article, we present the results of investigating the motility parameters of sperm cells in contact with surface-modified glass substrates using nanodiamond particles. The results show that the sperm swimming velocities are significantly improved within the range of 12%-52% compared to the control surface (untreated). Reactive oxygen species production is also decreased by 14% justifying the increase in swimming speed. Taken together, bonding these modified surfaces to sperm selection microfluidic devices could enhance their efficiency and further improve their outcomes offering new solutions to patients facing infertility.


Assuntos
Nanodiamantes , Humanos , Masculino , Microfluídica , Espécies Reativas de Oxigênio , Motilidade dos Espermatozoides , Espermatozoides
2.
Sci Rep ; 11(1): 18327, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526568

RESUMO

Sperm selection is crucial to assisted reproduction, influencing the success rate of the treatment cycle and offspring health. However, in the current clinical sperm selection practices, bypassing almost all the natural selection barriers is a major concern. Here, we present a biomimicry microfluidic method, inspired by the anatomy of the female reproductive tract, that separates motile sperm based on their rheotaxis behavior to swim against the flow into low shear rate regions. The device includes micropocket geometries that recall the oval-shaped microstructures of the female fallopian tube to create shear protected zones for sperm separation. Clinical tests with human samples indicate that the device is capable of isolating viable and highly motile sperm based on their rheotaxis responses, resulting in a separation efficiency of 100%. The device presents an automated alternative for the current sperm selection practices in assisted reproduction.


Assuntos
Separação Celular/métodos , Dispositivos Lab-On-A-Chip , Microfluídica/métodos , Espermatozoides/citologia , Algoritmos , Tubas Uterinas , Feminino , Humanos , Masculino , Modelos Teóricos , Óvulo , Motilidade dos Espermatozoides , Espermatozoides/fisiologia
3.
Comput Biol Med ; 127: 104061, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33126127

RESUMO

Spectrophotometry is an indirect non-invasive and quantitative method for specifying materials with unknown contents based on absorption behavior. This paper presents the first application of artificial neural network in spectrophotometry for quantification of human sperm concentration. A well-trained full spectrum neural network (FSNN) model is developed by examining the absorption response of sperm samples from 41 human subjects to different light spectra (wavelength from 390 to 1100 nm). It is shown that this FSNN accurately estimates sperm concentration based on the full absorption spectrum with over 93% prediction accuracy, and provides 100% agreement with clinical assessments in differentiating the samples of healthy donor from patient samples. We suggest the machine learning-based spectrophotometry approach with the trained FSNN model as a rapid, low-cost, and powerful technique to quantify sperm concentration. The performance of this technique is superior to available spectrophotometry methods currently used for semen analysis and will provide novel research and clinical opportunities for tackling male infertility.


Assuntos
Infertilidade Masculina , Análise do Sêmen , Humanos , Aprendizado de Máquina , Masculino , Espectrofotometria , Motilidade dos Espermatozoides , Espermatozoides
4.
Epilepsy Behav ; 19(3): 290-5, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20880756

RESUMO

In the present study, the effects of tramadol on pentylenetetrazole (PTZ)-induced seizures and involvement of nitric oxide (NO) were assessed in mice. To determine the threshold for clonic seizures, PTZ was administered intravenously. Tramadol was administered intraperitoneally (0.5-50mg/kg) 30 minutes prior to induction of seizures. The effects of the nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME; 0.5, 1, 5, and 10mg/kg), the nitric oxide precursor L-arginine (10, 30, and 60 mg/kg), and the nonspecific opioid receptor antagonist naloxone (0.1, 0.5, 1, and 5mg/kg) on the anticonvulsant effect of tramadol were investigated. Administration of tramadol (1mg/kg) increased the threshold for seizures induced with PTZ in a monophasic, dose-independent, and time-dependent manner. Acute administration of L-NAME (5 and 10mg/kg) inhibited the anticonvulsant effect of tramadol (1mg/kg), whereas L-arginine, in the noneffective dose range (30 and 60 mg/kg), potentiated the seizure threshold when co-administered with a subeffective dose of tramadol (0.5mg/kg). Naloxone partially and dose-independently antagonized the anticonvulsant effect of tramadol (1mg/kg). These results indicate that the anticonvulsant effect of tramadol is mediated by the nitric oxide pathway and also by classic opioid receptors.


Assuntos
Anticonvulsivantes/uso terapêutico , Óxido Nítrico/metabolismo , Convulsões/tratamento farmacológico , Convulsões/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tramadol/uso terapêutico , Análise de Variância , Animais , Arginina/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos , NG-Nitroarginina Metil Éster/farmacologia , Naloxona/uso terapêutico , Pentilenotetrazol/efeitos adversos , Convulsões/induzido quimicamente , Fatores de Tempo
5.
Reprod Sci ; 17(4): 391-400, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20228383

RESUMO

INTRODUCTION: In this study, we explained that exogenous cannabinoid, Delta(9)-tetrahydrocannabinol (THC), has a preventive effect in a murine model of lipopolysaccharide (LPS)-induced preterm delivery and the contribution of nitric oxide (NO) pathway as a mechanism involved in this process. STUDY DESIGN: Preterm delivery was induced by double dose of 35 microg/kg LPS with 3-hour interval on gestational day (gd) 15. Delta(9)-tetrahydrocannabinol was administered with (a) double dose (0.02, 0.05, 0.1, 0.5, 1, and 5 mg/kg) 1 hour before each LPS injection, on gd 15 and (b) single administration (0.05, 0.1, and 0.5 mg/kg,) on gds 13 and 14, and the double administration, 1 hour before each LPS injection. To assess the involved mechanism, either AM281 (CB1 receptor antagonist, 2 mg/kg) and AM630 (CB2 receptor antagonist, 5 mg/kg) or N(omega)-nitro-L-arginine methyl ester (L-NAME, 2 mg/kg) was administered 1 hour before each THC injection on gds 13, 14, and 15. The main outcome measurement was the incidence of preterm delivery after injection of last LPS dose. Any interaction in the incidence and time of preterm delivery was ruled out by administration of AM281, AM630, or L-NAME alone. RESULTS: Chronic THC treatment (0.5 mg/kg) significantly decreased the incidence of LPS-induced premature labor and increased the delivery time. Both AM281 and L-NAME reversed THC-induced attenuation of preterm delivery rate and pregnancy duration. Unlike AM281, AM630 did not influence the rate of preterm delivery in THC-treated mice. CONCLUSION: Delta(9)-Tetrahydrocannabinol contributes to the regulation of gestational duration in LPS-induced preterm delivery probably by NO coupling through the CB1 receptor.


Assuntos
Dronabinol/administração & dosagem , Óxido Nítrico/fisiologia , Nascimento Prematuro/prevenção & controle , Tocolíticos/administração & dosagem , Animais , Arginina/administração & dosagem , Arginina/análogos & derivados , Feminino , Lipopolissacarídeos , Camundongos , NG-Nitroarginina Metil Éster/administração & dosagem , Gravidez , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores
6.
Eur J Obstet Gynecol Reprod Biol ; 147(2): 166-72, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19744765

RESUMO

OBJECTIVES: This study evaluated the preventive effect of morphine on lipopolysaccharide (LPS)-induced preterm delivery and the contribution of the nitric oxide pathway as a mechanism involved in this process. STUDY DESIGN: Pregnant mice were treated with LPS: (a) single doses of 35, 50 and 75 microg/kg; (b) double doses of 25, 35 and 50 microg/kg with a 3-h interval, on gestational day 15. Each treatment group consisted of 5-10 mice and the main outcome measurements were the incidence and gestational duration after injection of the last LPS dose. Administration of LPS (35 microg/kg, with a 3-h interval) induced the highest incidence of preterm delivery in mice. For investigation of morphine effects on preterm delivery, animals were treated either with a single dose (10 or 20 mg/kg), or with double doses (5 or 10 mg/kg; with a 3-h interval) of morphine, 1h before each LPS injection. To assess the involved mechanism, either naltrexone (5 and 10 mg/kg) or N(omega)-nitro-l-arginine methyl ester (l-NAME, 2-10 mg/kg) was administered 1h before the first morphine administration. Any interaction in the incidence and/or time of preterm delivery was ruled out by other groups which received naltrexone or l-NAME, each alone. Data were analyzed by the Fisher's exact test for determination of preterm delivery incidences and by the one-way analysis of variance, followed by post-test Tukey, for determination of gestational duration. RESULTS: Although LPS induced premature labor and decreased the delivery time to gestational day 16, morphine treatment significantly decreased the incidence of LPS-induced premature labor by 50% and increased the delivery time to gestational day 17.6. Naltrexone (5 mg/kg) did not influence morphine-induced attenuation of preterm delivery rate and pregnancy duration. Unlike naltrexone, l-NAME (2 mg/kg) increased the rate of preterm delivery to 100% and decreased pregnancy duration to gestational day 16 in morphine-treated mice. In fact, l-NAME significantly attenuated morphine's preventive effect on preterm delivery. CONCLUSION: Morphine increases the gestational duration and decreases the preterm delivery rate induced by LPS probably through modulation in NO release. l-NAME, unlike naltrexone, reversed the effect of morphine on preterm delivery, demonstrating the involvement of nitric oxidergic pathway.


Assuntos
Lipopolissacarídeos/toxicidade , Morfina/farmacologia , Óxido Nítrico/fisiologia , Tocolíticos/farmacologia , Animais , Feminino , Masculino , Camundongos , NG-Nitroarginina Metil Éster/farmacologia , Naltrexona/farmacologia , Trabalho de Parto Prematuro/induzido quimicamente , Placenta/patologia , Gravidez
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