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1.
Nat Commun ; 15(1): 4829, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844438

RESUMEN

Orientation or axial selectivity, the property of neurons in the visual system to respond preferentially to certain angles of visual stimuli, plays a pivotal role in our understanding of visual perception and information processing. This computation is performed as early as the retina, and although much work has established the cellular mechanisms of retinal orientation selectivity, how this computation is organized across the retina is unknown. Using a large dataset collected across the mouse retina, we demonstrate functional organization rules of retinal orientation selectivity. First, we identify three major functional classes of retinal cells that are orientation selective and match previous descriptions. Second, we show that one orientation is predominantly represented in the retina and that this predominant orientation changes as a function of retinal location. Third, we demonstrate that neural activity plays little role on the organization of retinal orientation selectivity. Lastly, we use in silico modeling followed by validation experiments to demonstrate that the overrepresented orientation aligns along concentric axes. These results demonstrate that, similar to direction selectivity, orientation selectivity is organized in a functional map as early as the retina.


Asunto(s)
Orientación , Retina , Animales , Retina/fisiología , Ratones , Orientación/fisiología , Estimulación Luminosa , Ratones Endogámicos C57BL , Simulación por Computador , Percepción Visual/fisiología , Modelos Neurológicos , Orientación Espacial/fisiología , Células Ganglionares de la Retina/fisiología
2.
bioRxiv ; 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38585937

RESUMEN

Orientation or axial selectivity, the property of neurons in the visual system to respond preferentially to certain angles of a visual stimuli, plays a pivotal role in our understanding of visual perception and information processing. This computation is performed as early as the retina, and although much work has established the cellular mechanisms of retinal orientation selectivity, how this computation is organized across the retina is unknown. Using a large dataset collected across the mouse retina, we demonstrate functional organization rules of retinal orientation selectivity. First, we identify three major functional classes of retinal cells that are orientation selective and match previous descriptions. Second, we show that one orientation is predominantly represented in the retina and that this predominant orientation changes as a function of retinal location. Third, we demonstrate that neural activity plays little role on the organization of retinal orientation selectivity. Lastly, we use in silico modeling followed by validation experiments to demonstrate that the overrepresented orientation aligns along concentric axes. These results demonstrate that, similar to direction selectivity, orientation selectivity is organized in a functional map as early as the retina. One Sentence Summary: Development and organization of retinal orientation selectivity.

3.
Curr Opin Obstet Gynecol ; 26(3): 151-61, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24751998

RESUMEN

PURPOSE OF REVIEW: Magnetic-resonance-guided focused ultrasound surgery (MRgFUS) is a minimally invasive technique for the treatment of uterine fibroids. The purpose of this review is to highlight the impact of MRgFUS on fertility and reproductive outcomes. RECENT FINDINGS: The role of MRgFUS in the treatment of fibroids has been evolving since its introduction in 2004. Several new devices and techniques including location-specific treatment, volumetric therapy, and vessel-targeted therapy have been introduced over the last few years. Several case series report uncomplicated pregnancy following MRgFUS; however, results of the ongoing studies will further elucidate the utility of MRgFUS in patients planning future fertility. A systematic review of the literature was completed and studies that reported quality of life at baseline and after 6 months were included in a meta-analysis. SUMMARY: MRgFUS represents a minimally invasive treatment for uterine fibroids that is able to improve the quality of life and fibroid size with durability. It is possible that MRgFUS could be the treatment of choice for patients desiring future fertility; however, further investigation is needed.


Asunto(s)
Fertilidad , Leiomioma/patología , Imagen por Resonancia Magnética , Terapia por Ultrasonido , Neoplasias Uterinas/patología , Adulto , Medicina Basada en la Evidencia , Femenino , Humanos , Leiomioma/terapia , Persona de Mediana Edad , Selección de Paciente , Embarazo , Calidad de Vida , Resultado del Tratamiento , Neoplasias Uterinas/terapia
5.
Semin Reprod Med ; 32(1): 43-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24390920

RESUMEN

Female genital tract microbiota play a crucial role in maintaining health. Disequilibrium of the microbiota has been associated with increased risk of pelvic infections. In recent years, culture-independent molecular techniques have expanded understanding of the composition of genital microbiota and the dynamic nature of the microbiota. There is evidence that upper genital tract may not be sterile and may harbor microflora in the physiologic state. The isolation of bacterial vaginosis-associated organisms in women with genital infections establishes a link between pelvic infections and abnormal vaginal flora. With the understanding of the composition of the microbiota in healthy and diseased states, the next logical step is to identify the function of the newly identified microbes. This knowledge will further expand our understanding of the causation of pelvic infections, which may lead to more effective prevention and treatment strategies.


Asunto(s)
Microbiota/fisiología , Enfermedad Inflamatoria Pélvica/microbiología , Biodiversidad , Femenino , Enfermedades de los Genitales Femeninos/microbiología , Genitales Femeninos/microbiología , Infecciones por VIH/complicaciones , Infecciones por VIH/microbiología , VIH-1 , Humanos , Embarazo , Factores de Riesgo , Vaginitis por Trichomonas/microbiología , Vagina/microbiología , Vaginosis Bacteriana/microbiología
6.
Int J Gynaecol Obstet ; 122(3): 253-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23820030

RESUMEN

OBJECTIVE: To determine use of and attitudes toward complementary and alternative medicine (CAM) among infertility patients and subspecialty physicians. METHODS: Infertility patients were asked to complete anonymous written surveys at an academic infertility practice; members of the Society for Reproductive Endocrinology and Infertility were electronically surveyed. Both groups were assessed regarding their use of and attitudes toward CAM. RESULTS: The response rate was 32.1% (115/358) among patients and 22.6% (225/995) among physicians (P<0.05). In total, 105 (91.3%; 95% confidence interval [CI], 85.8-96.2) patients used CAM, and 84 (73.0%; 95% CI, 64.9-81.1) regarded it as beneficial to their fertility treatment. However, only 30 (26.1%; 95% CI, 18.0-34.0) patients reported CAM use to physicians, with the most common reason being that they were "never asked." Overall, 202 (89.8%; 95% CI, 85.9-93.8) physicians reported inquiring about CAM. CONCLUSION: Significant discrepancies exist between subfertile patients and physicians in attitudes toward the use of CAM. The current prevalence of CAM use among infertility patients requires greater physician attention and justifies further study on the risks and benefits of integrating CAM into the biomedical treatment of infertility.


Asunto(s)
Actitud del Personal de Salud , Actitud Frente a la Salud , Terapias Complementarias/métodos , Infertilidad/terapia , Adulto , Terapias Complementarias/estadística & datos numéricos , Recolección de Datos , Encuestas de Atención de la Salud , Humanos , Masculino , Persona de Mediana Edad , Relaciones Médico-Paciente , Pautas de la Práctica en Medicina
7.
Int J Gynaecol Obstet ; 122(3): 202-6, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23796256

RESUMEN

BACKGROUND: The use of complementary and alternative medicine (CAM) by patients and physicians has increased markedly in recent years. Many case reports, case series, and uncontrolled trials of varying quality have been completed; however, there is now a slowly increasing number of randomized controlled trials (RCTs) examining the use of CAM. OBJECTIVES: To identify, survey, and review RCTs investigating the use of CAM for infertility treatment. SEARCH STRATEGY: The MEDLINE and Cochrane databases were electronically searched. SELECTION CRITERIA: RCTs examining modalities for treatment or improvement of health status were reviewed. DATA COLLECTION AND ANALYSIS: RCTs were included based on use of objective measures, articles written in English, availability through the University of Michigan database, and clear published clinical outcomes. MAIN RESULTS: Thirty-seven articles assessing a variety of CAM modalities met inclusion criteria. Acupuncture, selenium supplementation, weight loss, and psychotherapeutic intervention had 3 or more studies demonstrating beneficial effect. Other interventions had been studied less and evidence for them was limited. CONCLUSIONS: Although there is preliminary evidence of the effectiveness of some CAM interventions among infertile patients, many of these interventions require further investigation before they can be considered for routine clinical use.


Asunto(s)
Terapias Complementarias/métodos , Infertilidad Femenina/terapia , Infertilidad Masculina/terapia , Terapia por Acupuntura/métodos , Suplementos Dietéticos , Femenino , Estado de Salud , Humanos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Selenio/administración & dosificación
8.
J Assist Reprod Genet ; 30(7): 865-75, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23779099

RESUMEN

PURPOSE: To highlight emerging techniques aimed at improving oocyte cryopreservation. METHODS: Review of available and relevant literature through Pubmed and Medline searches. RESULTS: Oocyte cryopreservation is an increasingly common procedure utilized for assisted reproduction and may benefit several patient populations. Therefore, improving efficiency is paramount in realizing the tremendous promise of this approach. However, in addition to numerous studies looking to improve oocyte cryopreservation efficacy via examination of variables involved with protocol methodology, such as type/concentration of cryoprotectant (CPA), type of storage device, or cooling/warming rates, there are more novel approaches for improvement. These alternate approaches include utilizing different the stages of oocytes, examining alteration of basal media and buffer composition, optimizing CPA exchange protocols and device loading through use of automated technology, as well as examination/manipulation of oocyte cellular composition to improve cryotolerance. Finally, elucidating more accurate or insightful indicators of "success" is crucial for continued improvement of oocyte cryopreservation. CONCLUSION: Oocyte cryopreservation has improved dramatically in recent years and is receiving widespread clinical use. Novel approaches to further improve success, as well as improved methods to assess this success will aid in continued improvement.


Asunto(s)
Criopreservación/métodos , Oocitos/fisiología , Animales , División Celular , Supervivencia Celular , Crioprotectores , Humanos , Ratones , Oocitos/citología , Técnicas Reproductivas Asistidas
9.
PLoS One ; 7(8): e42451, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22900022

RESUMEN

BACKGROUND: TC10 is a small GTPase found in lipid raft microdomains of adipocytes. The protein undergoes activation in response to insulin, and plays a key role in the regulation of glucose uptake by the hormone. METHODOLOGY/PRINCIPAL FINDINGS: TC10 requires high concentrations of magnesium in order to stabilize guanine nucleotide binding. Kinetic analysis of this process revealed that magnesium acutely decreased the nucleotide release and exchange rates of TC10, suggesting that the G protein may behave as a rapidly exchanging, and therefore active protein in vivo. However, in adipocytes, the activity of TC10 is not constitutive, indicating that mechanisms must exist to maintain the G protein in a low activity state in untreated cells. Thus, we searched for proteins that might bind to and stabilize TC10 in the inactive state. We found that Caveolin interacts with TC10 only when GDP-bound and stabilizes GDP binding. Moreover, knockdown of Caveolin 1 in 3T3-L1 adipocytes increased the basal activity state of TC10. CONCLUSIONS/SIGNIFICANCE: Together these data suggest that TC10 is intrinsically active in vivo, but is maintained in the inactive state by binding to Caveolin 1 in 3T3-L1 adipocytes under basal conditions, permitting its activation by insulin.


Asunto(s)
Adipocitos/metabolismo , Caveolinas/metabolismo , Proteínas de Unión al GTP rho/metabolismo , Células 3T3-L1 , Animales , Sitios de Unión , Caveolina 1/metabolismo , Caveolinas/genética , Estabilidad de Enzimas , Guanosina Difosfato/metabolismo , Magnesio/química , Magnesio/metabolismo , Ratones , Simulación del Acoplamiento Molecular , Nucleótidos/metabolismo , Unión Proteica , Interferencia de ARN , Proteína de Unión al GTP cdc42/química , Proteína de Unión al GTP cdc42/metabolismo , Proteínas de Unión al GTP rho/química
10.
J Assist Reprod Genet ; 28(8): 711-24, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21614519

RESUMEN

PURPOSE: Minimizing environmental stress helps maintain cellular homeostasis and is a crucial component in optimizing embryo development in vitro and resulting ART success. One stressor of particular interest is pH. Biologic buffers, such as HEPES and MOPS, are valuable tools for stabilizing pH. The objective of this manuscript is to summarize efficacy and impact of various pH buffers used during IVF lab procedures METHODS: Keyword searches were performed using Pubmed and Medline and relevant literature reviewed. RESULTS: Various pH buffers have been used with varying degrees of success for gamete and embryo processing in a variety of animal species, as well as in human. CONCLUSION: Though biologic buffers off a means to improve pH stability, not all buffers may be appropriate for use with gametes and embryos. Specific buffers may have undesired effects, and these may be buffer, species, cell type or concentration dependent. Continued research is needed to further refine and improve the use of biologic buffers for use in human ART.


Asunto(s)
Medios de Cultivo/química , Fertilización In Vitro/métodos , Animales , Tampones (Química) , Criopreservación/métodos , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , HEPES , Humanos , Concentración de Iones de Hidrógeno , Ratones , Morfolinas , Ácidos Sulfónicos , Temperatura
11.
Am J Obstet Gynecol ; 203(6): 595.e17-22, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20869037

RESUMEN

OBJECTIVE: The purpose of this study was to determine the effect of levator defects on perineal position and movement irrespective of prolapse status. STUDY DESIGN: Forty women from an ongoing study were divided into 2 groups of 20 women with and without severe levator defects. Prolapse status was matched between groups, with 50% of the women having stage III or greater anterior wall prolapse. Perineal structure locations were measured against standard axes on magnetic resonance scans at rest, maximum contraction (Kegel), and maximum Valsalva maneuver. Differences in location were calculated and compared. RESULTS: In women with levator defects, independently of prolapse status: (1) At rest, the perineal body was 1.3 cm, and the anal sphincter was 1.0 cm more caudal (P ≤ .01); at maximum contraction, the perineal body and the anal sphincter were both 1.2 cm more caudal (P ≤ .01); with maximum Valsalva maneuver, the perineal body was 1.3 cm more caudal, and the anal sphincter was 1.2 cm more caudal (P ≤ .01). (2) At rest, the levator hiatus was 0.8 cm larger, and the urogenital hiatus was 1.0 cm larger (P ≤ .01). (3) At rest, the bladder was 0.07 cm more posterior (P ≤ .02); with maximum contraction, it was 1.9 cm lower (P ≤ .02). (4) With maximum Valsalva maneuver, the bladder was 1.5 cm lower and displaced further caudally (P ≤ .03). CONCLUSION: When we controlled for prolapse, the women with levator defects had a more caudal location of their perineal structures and larger hiatuses at rest, maximum contraction, and maximum Valsalva maneuver.


Asunto(s)
Canal Anal/anomalías , Diafragma Pélvico/anomalías , Prolapso de Órgano Pélvico/diagnóstico , Prolapso de Órgano Pélvico/cirugía , Adulto , Anciano , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Procedimientos Quirúrgicos Ginecológicos/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Perineo/fisiopatología , Embarazo , Valores de Referencia , Medición de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
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