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1.
IEEE Trans Nanobioscience ; 15(7): 756-764, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27740491

RESUMO

In this work, we demonstrate how an innovative, out-of-cleanroom customized CD/DVD fabrication process can be successfully used for mass production of biosensors with thin-film electrodes. We show that silver and gold electrodes can be used for impedimetric and voltammetric biosensing applications, both in presence and absence of a redox mediator. We modeled the redox/non-redox electrodes impedance through equivalent electrical circuits, and we evaluated their transfer function sensitivity with a one-factor-at-a-time approach. Using this approach, we introduced a new prediction method to find which equivalent electrical circuit elements contribute more to the transfer function variations, then we experimentally validated the predictions measuring the electrodes electrochemical impedance spectroscopy responses with relevant self-assembled monolayer molecules immobilized on them, i.e., MCH and DTSP. We also assess the silver electrodes long-term stability with impedance spectroscopy measurements over a period of 1200 hours, proving their possible use in point-of-care applications. Finally, we also prove that the sensors correctly perform in a practical case, i.e., as a lactic acid biosensor, by studying the optimization of the biosensor efficiency through different enzyme immobilization methods. By comparing lactate oxidase enzyme direct adsorption and covalent binding to DTSP self-assembling monolayers, we found that covalent binding to DTSP can boost the catalytic current of about 40% with respect to that obtained from the direct adsorption of the same enzyme concentration.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Ácido Láctico/análise , Prata/química , Impedância Elétrica , Eletrodos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Ácido Láctico/metabolismo , Oxigenases de Função Mista/química , Oxigenases de Função Mista/metabolismo
2.
Opt Lett ; 40(2): 221-4, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25679849

RESUMO

In this work we propose a method to enhance and control the angular sensitivity of a grating coupled surface plasmon resonance (GCSPR) sensor. We lighted a silver grating, mounted in conical configuration, with a laser source and we measured the transmittance of the grating as a function of the azimuthal angle. To evaluate the sensitivity, grating surface was functionalized with four different alkanethiol self assembled monolayers (SAM) and the correspondent azimuthal transmittance peak shifts were measured. The sensitivity control was performed by simply change the light incident angle. This method offers the possibility to design dynamic GCSPR sensor benches that can be used to amplify the SPR angle shift at any step of a biological detection process.


Assuntos
Ressonância de Plasmônio de Superfície/métodos , Ressonância de Plasmônio de Superfície/instrumentação
3.
Appl Opt ; 53(26): 5969-76, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25321677

RESUMO

This work presents an integrated plasmonic biosensing device consisting of a one-dimensional metallic lamellar grating designed to exploit extraordinary transmission of light toward an underlying silicon photodetector. By means of finite element simulations, the grating parameters have been optimized to maximize the light transmission variation induced by the functionalization of the gold nanostructures. An optimized grating was fabricated using an electron beam process and an optoelectronic test bench suitable for sample tests was developed. A clear difference in the grating transmitted light due to surface functionalization was observed in presence of TM polarized illumination.


Assuntos
Biopolímeros/análise , Técnicas Biossensoriais/instrumentação , Iluminação/instrumentação , Fotometria/instrumentação , Refratometria/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento
5.
J Urol ; 165(5): 1510-3, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11342907

RESUMO

PURPOSE: We determined whether varicocele treatment before intrauterine insemination significantly affects intrauterine insemination success rates. MATERIALS AND METHODS: A total of 58 infertile couples, of whom the women had normal evaluations and men had abnormal semen analyses and a history of varicocele, were included in this study. They were identified after reviewing the charts of all women undergoing intrauterine insemination for male factor infertility at our center. Of the men 24 participated in 63 intrauterine insemination cycles without varicocele treatment, while in the remaining 34 varicocele was treated before a total of 101 intrauterine insemination cycles. Variables associated with pregnancy or live birth were analyzed using repeat measures logistic regression with generalized estimating equation techniques. An initial stepwise generalized estimating equation was performed without including varicocele treatment status. Subsequently varicocele treatment status and the significant associated factors were included in analysis. The semen characteristics of untreated and treated varicocele groups were compared with repeat measures analysis of variance. RESULTS: On pre-wash semen analysis patients with untreated varicocele had significantly higher mean motility plus or minus standard error than patients whose varicoceles were treated (48.6% +/- 2.3% versus 38.1% +/- 1.8%, p = 0.02). However, no statistically significant difference was noted in the mean post-wash total motile sperm count in the treated and untreated groups (7.2 +/- 1.0 versus 14.8 +/- 2.6, p = 0.1). Despite these findings the pregnancy and live birth rates per cycle were significantly higher in patients in whom varicocele was treated than in those without varicocele treatment (11.8% versus 6.3%, p = 0.04 and 11.8% versus 1.6%, p = 0.007, respectively). CONCLUSIONS: Varicocele treatment may not improve semen characteristics in all men but it appears to improve pregnancy and live birth rates among couples undergoing intrauterine insemination for male factor infertility. A functional factor not measured on routine semen analysis may affect pregnancy rates in this setting. Men should be screened for varicocele before intrauterine insemination is initiated for male factor infertility.


Assuntos
Infertilidade Masculina/terapia , Inseminação Artificial , Varicocele/cirurgia , Feminino , Humanos , Masculino , Gravidez , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Varicocele/fisiopatologia
6.
J Assist Reprod Genet ; 18(1): 26-9, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11292992

RESUMO

PURPOSE: Our purpose was to examine the effect of treated mild pelvic disease on the outcome of superovulation with intrauterine insemination (SO/IUI). METHODS: Three hundred cycles of SO/IUI were retrospectively reviewed for 118 women with laparoscopically treated minimal/mild endometriosis and 67 cycles for 28 women with minimal/mild distal tubal disease/adnexal adhesions and compared with 265 cycles in 111 couples with idiopathic infertility. RESULTS: The monthly fecundity rate (MFR) of 6.8% and live birth rate (LBR) of 6% in the endometriosis group were significantly lower (P = 0.002) than those in the idiopathic infertility group (MFR = 13.5%, LBR = 12.1%). The 10.9% MFR and 7.5% LBR in the minimal/mild tubal/adnexal disease were not significantly different from those in the other two groups. CONCLUSIONS: MFR and LBR were higher after SO/IUI in idiopathic infertility compared to those for treated mild/minimal endometriosis or mild/minimal tubal/adnexal adhesions. However, SO/IUI still remains a reasonable option for both these groups prior to IVF-ET.


Assuntos
Doenças dos Anexos/fisiopatologia , Endometriose/fisiopatologia , Inseminação Artificial Homóloga/métodos , Superovulação/fisiologia , Doenças dos Anexos/patologia , Doenças dos Anexos/cirurgia , Adulto , Endometriose/patologia , Endometriose/cirurgia , Feminino , Humanos , Modelos Logísticos , Masculino , Gravidez , Resultado da Gravidez , Estudos Retrospectivos
7.
Int J Fertil Womens Med ; 45(5): 314-20, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11092702

RESUMO

OBJECTIVE: To examine the presence of reactive oxygen species (ROS) in the follicular fluid of women undergoing in vitro fertilization (IVF) and identify its role in pregnancy outcome. STUDY DESIGN: In this prospective study, ROS and total antioxidant capacity (TAC) levels were measured by the chemiluminescence method in the follicular fluid of 53 women. Age, number of oocytes recovered, percentage of oocytes fertilized, ROS and TAC levels were compared in women who did and did not become pregnant. RESULTS: Patients who become pregnant had significantly higher log-transformed ROS levels (1.01 +/- 0.14, P = 0.031 than those who did not (0.69 +/- 0.08). Women with endometriosis or male factor infertility who became pregnant had significantly higher ROS levels (1.44 +/- 0.23 and 1.31 +/- 0.19) than those who did not (0.60 +/- 0.17 and 0.67 +/- 0.16; P < .006 and P < .01). CONCLUSION: Follicular fluid ROS, at low concentrations, may be a potential marker for predicting success in IVF patients.


Assuntos
Fertilização in vitro , Líquido Folicular/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores Etários , Análise de Variância , Feminino , Humanos , Folículo Ovariano/metabolismo , Gravidez , Resultado da Gravidez , Estatísticas não Paramétricas
8.
J Am Assoc Gynecol Laparosc ; 7(2): 201-9, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10806263

RESUMO

STUDY OBJECTIVES: To review diagnoses, complications, and surgical findings in women treated for abnormal uterine bleeding by operative hysteroscopy, and to assess the accuracy of preoperative transvaginal ultrasound (TVS), saline-infusion sonography (SIS), diagnostic hysteroscopy, and endometrial biopsy. DESIGN: Retrospective study (Canadian task force classification II-2). SETTING: Tertiary care academic medical center. PATIENTS: Three hundred seventy-five women. Intervention. Operative hysteroscopy for abnormal uterine bleeding. MEASUREMENTS AND MAIN RESULTS: Main indications for hysteroscopy were postmenopausal bleeding (164 patients, 43.7%) and abnormal premenopausal uterine bleeding (211, 56.3%). Main pathology findings were endometrial polyps (172, 45.9%) and submucous myomas (105, 28%). Polyps had histologic abnormalities in 18 patients. Sensitivity of preoperative diagnostic tools for all intrauterine abnormalities and specifically for myomas and polyps was TVS 74% and 39%, SIS 96% and 96%, hysteroscopy 100% and 99%, and Pipelle biopsy 24% and 10%. The complication rate was 1.3%. Postmenopausal women felt significantly more improvement in symptoms (p = 0.02), and were more satisfied (p

Assuntos
Histeroscopia , Distúrbios Menstruais/diagnóstico , Biópsia , Neoplasias do Endométrio/patologia , Endométrio/patologia , Feminino , Humanos , Hiperplasia , Leiomiossarcoma/patologia , Distúrbios Menstruais/diagnóstico por imagem , Pessoa de Meia-Idade , Pólipos/patologia , Pós-Menopausa , Estudos Retrospectivos , Cloreto de Sódio , Ultrassonografia
9.
J Assist Reprod Genet ; 16(9): 476-82, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10530401

RESUMO

PURPOSE: This study sought (i) to investigate the relationship between postwash total motile sperm count and postwash percentage motile sperm in predicting successful intrauterine insemination and (ii) to determine the minimal postwash total motile sperm count required to achieve pregnancy with intrauterine insemination. METHODS: Five hundred four women, who underwent 1636 intrauterine insemination cycles with their partner's sperm for infertility treatment from 1993 through 1995, were included in this retrospective study. All patient charts were reviewed for age, infertility etiology, ovarian stimulation regimens, semen characteristics, and treatment outcome. To determine the relationship between total motile sperm count and intrauterine insemination outcome, patients were grouped as (1) less than 0.5 million, (2) 0.5 to 1 million, (3) 1 to 5 million, (4) greater than 5 million, and (5) greater than 20 million. RESULTS: Similar live birth rates (per cycle) were seen among the postwash total motile sperm count groups: group 1, 3.5%; group 2, 2.4%; group 3, 7.0%; group 4, 6.9%; and group 5, 7.0% (P = 0.37). However, regardless of the postwash total motile sperm count, the postwash motility predicted intrauterine insemination success at a cutoff value of 40%. CONCLUSIONS: The percentage of postwash sperm motility, and not the postwash total motile sperm count, can predict successful intrauterine insemination outcome. Such information can be useful in counseling patients regarding their chance of success with intrauterine insemination and in determining when alternate methods of assisted reproduction may be a better approach.


Assuntos
Infertilidade Masculina , Inseminação Artificial Homóloga , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Feminino , Humanos , Masculino , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Retrospectivos
10.
Fertil Steril ; 72(4): 613-8, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10521097

RESUMO

OBJECTIVE: To identify whether sperm characteristics after washing and/or ovulation induction cycle characteristics can predict the occurrence of multiple conception in patients undergoing ovarian stimulation and IUI. DESIGN: Retrospective study. SETTING: A gynecology clinic and an andrology laboratory at a tertiary care facility. PATIENT(S): One hundred patients with single pregnancies and 22 patients with multiple pregnancies. INTERVENTION(S): Patients underwent ovarian stimulation and IUI with their partner's sperm. MAIN OUTCOME MEASURE(S): Relation of patient characteristics, ovarian stimulation, and sperm characteristics after washing to the occurrence of multiple pregnancy. RESULT(S): The mean serum E2 level on the day of hCG injection was significantly higher in the multiple conception group, but the number of follicles was not. The total sperm count, total motile sperm count, and sperm motility after washing did not differ between the groups. However, couples with multiple pregnancies had sperm with a significantly higher amplitude of lateral head movement than couples with single pregnancies. A peak E2 level of >583 pg/mL on the day of hCG injection and sperm with an ALH of >4 microm after washing predicted the occurrence of multiple pregnancy. CONCLUSION(S): Sperm with an amplitude of lateral head movement of >4 microm and a peak E2 level of >583 pg/mL are significant risk factors for multiple pregnancy in patients undergoing IUI.


Assuntos
Inseminação Artificial Homóloga , Ovário/fisiologia , Gravidez Múltipla , Adulto , Gonadotropina Coriônica/uso terapêutico , Clomifeno/uso terapêutico , Estradiol/sangue , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Humanos , Masculino , Menotropinas/uso terapêutico , Análise Multivariada , Ovário/efeitos dos fármacos , Gravidez , Estudos Retrospectivos , Fatores de Risco , Sêmen/fisiologia , Cabeça do Espermatozoide/fisiologia , Motilidade dos Espermatozoides/fisiologia
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