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1.
Hum Reprod ; 39(6): 1316-1322, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38636947

RESUMEN

STUDY QUESTION: Does BMI of gestational carriers (GCs) affect perinatal outcomes after embryo transfer? SUMMARY ANSWER: Overweight and class I obesity in GCs does not affect the rate of good perinatal outcomes. WHAT IS KNOWN ALREADY: The use of GCs is increasing, but uniform guidance regarding optimal BMI for GCs is lacking. Women with obesity who conceive without fertility treatment or through autologous or donor in vitro fertilization are at higher risk of adverse maternal and fetal outcomes, but data on obesity in GCs are very limited. STUDY DESIGN, SIZE, DURATION: We performed a retrospective cohort study of 1121 GC cycles from January 2015 to December 2020 at US Fertility, the largest national partnership of fertility practices in the USA. PARTICIPANTS/MATERIALS, SETTING, AND METHODS: All GC cycles performed at a large network of fertility practices were reviewed. Same-sex partners undergoing co-IVF were excluded. The primary outcome was good perinatal outcome from the first embryo transfer, defined as a singleton live birth at ≥37 weeks of gestation with birth weight between 2500 and 4000 g. Secondary outcome measures included frequencies of live birth, clinical pregnancy, miscarriage, full-term birth, low birth weight, large for gestational age, and cesarean delivery. A generalized linear model (log-binomial) was used for each to compare outcomes across BMI groups using normal BMI (20-24.9 kg/m2) as the reference group. Risk ratios and 95% CIs were estimated for each category group relative to normal BMI. MAIN RESULTS AND THE ROLE OF CHANCE: We identified 1121 cycles in which GCs underwent first embryo transfer, of which 263 (23.5%) were in GCs with BMI >30. Demographics and reproductive history for GCs did not differ by BMI groups. The age of intended parents, use of frozen eggs, and fresh embryo transfers were higher with increasing BMI group. There were no statistically significant associations between BMI and good perinatal outcomes, live birth, clinical pregnancy, biochemical, spontaneous abortion, or low birth weight. However, among live births, higher BMI was significantly associated with birth by cesarean (P = 0.015) and large for gestational age infants (P = 0.023). LIMITATIONS, REASONS FOR CAUTION: This was a retrospective study, and there may be unmeasured confounders. The number of patients with BMI <20 or ≥35 was small, limiting the power for these groups. We were not able to assess all maternal and fetal outcomes. WIDER IMPLICATIONS OF THE FINDINGS: In this study, we did not identify any significant impact of BMI on the chances of having a good perinatal outcome. Prior research studies have been inconsistent and this is the largest study to date. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received for this work. The authors do not have any conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Índice de Masa Corporal , Transferencia de Embrión , Obesidad , Resultado del Embarazo , Humanos , Femenino , Embarazo , Estudios Retrospectivos , Adulto , Transferencia de Embrión/métodos , Transferencia de Embrión/estadística & datos numéricos , Resultado del Embarazo/epidemiología , Obesidad/complicaciones , Obesidad/epidemiología , Madres Sustitutas , Recién Nacido , Nacimiento Vivo , Fertilización In Vitro/métodos , Cesárea/estadística & datos numéricos , Complicaciones del Embarazo/epidemiología
2.
Reprod Biomed Online ; 49(1): 103976, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38733676

RESUMEN

RESEARCH QUESTION: Can immature oocytes vitrified and warmed using a short protocol survive and resume meiosis? DESIGN: This study examined modifications of oocyte vitrification and warming protocols that reduce the length of exposure to vitrification and warming solutions. In total, 561 germinal vesicles and 218 metaphase I oocytes that were immature at oocyte retrieval were vitrified at room temperature for 2 min. Warming was performed at 37°C for 2 min. Resumption of meiotic activity was evaluated after 24 and 48 h of culture. Two different commercially available vitrification and warming kits were used for comparison. RESULTS: Ninety-five percent of germinal vesicles survived, with no difference observed between the kits. The survival of metaphase I oocytes was, on average, 95.4% and did not differ significantly between the kits. Of the 533 germinal vesicles that survived, 491 converted to metaphase I oocytes (92.1%). After culture for 48 h, 54.4% converted to metaphase II oocytes. In addition, of the 208 metaphase I oocytes that survived warming, 84.1% converted to metaphase II oocytes after 24 h of culture. These maturation rates were similar to those of non-vitrified oocytes. CONCLUSIONS: Vitrification and warming of oocytes at different nuclear maturation stages can be performed with 2 min of exposure to hypertonic solution and 2 min of exposure to hypotonic solution, respectively. This approach reduces exposure of the oocytes to room temperature during dehydration and rehydration. Warming in 0.5M sucrose helps to maintain and support the potential of oocytes to resume nuclear meiotic activity, and conversion from germinal vesicles to metaphase I and metaphase II oocytes.


Asunto(s)
Criopreservación , Meiosis , Oocitos , Vitrificación , Oocitos/citología , Oocitos/fisiología , Humanos , Meiosis/fisiología , Femenino , Criopreservación/métodos , Supervivencia Celular , Técnicas de Maduración In Vitro de los Oocitos/métodos , Adulto
3.
Laryngorhinootologie ; 92(9): 589-93, 2013 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-23996551

RESUMEN

OBJECTIVE: Peritonsillar abscess (PTA) is a common problem in otorhinolaryngology. The pathogenesis, supporting factors and optimal therapy are matter of numerous investigations. We studied retrospectively smoking habits, preoperative coagulation screening and the applied therapy of PTA. MATERIAL AND METHODS: Data from 460 patients who underwent treatment for PTA between 2000 and 2009 at Dessau Medical Center were retrospectively analysed. RESULTS: The highest incidence of PTA was found in young men, the prevalence of nicotine consumption was clearly increased in relation to the general population. The therapy of first choice was abscess tonsillectomy. Even with preoperative pathological coagulation-parameters no increased risk of secondary bleeding was shown. CONCLUSIONS: The part of smokers of patients with PTA is increased in comparison to the correspondent population of same age. A routine preoperative coagulation screening has a low benefit relating to the prediction of the risk of secondary bleeding. Abscess tonsillectomy is a safe method and has proved itself in clinical daily routine.


Asunto(s)
Pruebas de Coagulación Sanguínea , Tamizaje Masivo , Absceso Peritonsilar/etiología , Absceso Peritonsilar/cirugía , Hemorragia Posoperatoria/prevención & control , Cuidados Preoperatorios , Fumar/efectos adversos , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Estudios Transversales , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Absceso Peritonsilar/diagnóstico por imagen , Absceso Peritonsilar/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales , Fumar/epidemiología , Tomografía Computarizada por Rayos X , Tonsilectomía , Adulto Joven
4.
Neuron ; 5(6): 789-96, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2176510

RESUMEN

GABA, the major inhibitory neurotransmitter in the mammalian brain, binds to GABAA receptors, which form chloride ion channels. The predicted structure of the GABAA receptor places a consensus phosphorylation site for cAMP-dependent protein kinase (PKA) on an intracellular domain of the channel. Phosphorylation by various protein kinases has been shown to alter the activity of certain ligand- and voltage-gated ion channels. We have examined the role of phosphorylation by the catalytic subunit of PKA in the regulation of GABAA receptor channel function using whole-cell and excised outside-out patch-clamp techniques. Inclusion of the catalytic subunit of PKA in the recording pipettes significantly reduced GABA-evoked whole-cell and single-channel chloride currents. Both heat inactivation of PKA and addition of the specific protein kinase inhibitor peptide prevented the reduction of GABA-evoked currents by PKA. Neither mean channel open time nor channel conductance was affected by PKA. The reduction in GABA receptor current by PKA was primarily due to a reduction in channel opening frequency.


Asunto(s)
AMP Cíclico/farmacología , Neuronas/fisiología , Proteínas Quinasas/farmacología , Receptores de GABA-A/fisiología , Médula Espinal/citología , Animales , Membrana Celular/fisiología , Células Cultivadas , Canales de Cloruro , Conductividad Eléctrica , Calor , Activación del Canal Iónico/efectos de los fármacos , Proteínas de la Membrana/fisiología , Ratones , Péptidos/farmacología , Fosforilación , Cloruro de Potasio/farmacología , Inhibidores de Proteínas Quinasas , Proteínas Quinasas/metabolismo , Médula Espinal/embriología , Ácido gamma-Aminobutírico/farmacología
5.
Mol Cell Biol ; 20(10): 3442-8, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10779334

RESUMEN

Protein kinase inhibitor (PKI) is a potent endogenous inhibitor of the cyclic AMP (cAMP)-dependent protein kinase (PKA). It functions by binding the free catalytic (C) subunit with a high affinity and is also known to export nuclear C subunit to the cytoplasm. The significance of these actions with respect to PKI's physiological role is not well understood. To address this, we have generated by homologous recombination mutant mice that are deficient in PKIalpha, one of the three isoforms of PKI. The mice completely lack PKI activity in skeletal muscle and, surprisingly, show decreased basal and isoproterenol-induced gene expression in muscle. Further examination revealed reduced levels of the phosphorylated (active) form of the transcription factor CREB (cAMP response element binding protein) in the knockouts. This phenomenon stems, at least in part, from lower basal PKA activity levels in the mutants, arising from a compensatory increase in the level of the RIalpha subunit of PKA. The deficit in gene induction, however, is not easily explained by current models of PKI function and suggests that PKI may play an as yet undescribed role in PKA signaling.


Asunto(s)
Proteínas Portadoras/genética , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular , Músculo Esquelético/fisiología , Animales , AMP Cíclico/farmacología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Inhibidores Enzimáticos , Regulación de la Expresión Génica , Homocigoto , Isoproterenol/farmacología , Ratones , Ratones Noqueados , Fosforilación , Isoformas de Proteínas/genética , Transducción de Señal , Activación Transcripcional
6.
Cell Prolif ; 39(1): 15-28, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16426419

RESUMEN

Recent research in cancer progression and treatment indicates that many forms of cancer arise from the development of a small subpopulation of abnormal cancer stem cells (CSCs) that promote cancer growth and spread. Many potential treatments preferentially interact with cells at certain stages of the cell cycle by either selective killing or halting the cell cycle, such as intense, nanosecond-duration pulsed electric fields (nsPEFs). Simple mathematical models of unfed cancer cell populations at the plateau of their growth characteristics may estimate the long-term consequences of these treatments on proliferating and quiescent cell populations. Applying such a model with no transition from the quiescent to proliferating state shows that it is possible for the proliferating cell population to fall below 1 if the quiescent cell population obtains a sufficient competitive advantage with respect to nutrient consumption and/or survival rate. Introducing small, realistic transition rates did not appreciably alter short-term or long-term population behaviour, indicating that the predicted small cell population behaviour (< 1 cell) is not an artefact of the simpler model. Experimental observations of nsPEF-induced effects on the cell cycle suggest that such a model may serve as a first step in assessing the viability of a given cancer treatment in vitro prior to clinical application.


Asunto(s)
Ciclo Celular , Modelos Biológicos , Neoplasias/patología , Células Madre Neoplásicas/citología , Animales , División Celular , Línea Celular Tumoral , Supervivencia Celular , Transformación Celular Neoplásica , Humanos
7.
Mol Endocrinol ; 5(9): 1246-56, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1770951

RESUMEN

Human cDNA clones for a heat-stable protein kinase inhibitor (PKI) protein of the cAMP-dependent protein kinase (PKA) were isolated using a mouse PKI cDNA fragment. Two human cDNA clones of 1.7 and 2.0 kb were sequenced and shown to encode the entire open reading frame of 228 nucleotides. Together these clones comprised 2147 nucleotides of the mRNA. The deduced amino acid sequence of the human clones showed 100% identity to the rabbit skeletal muscle PKI protein and 97% identity to the mouse brain PKI. The mouse and human PKI cDNAs shared nucleotide homology in their 3' untranslated regions as well as in the 32 nucleotides immediately 5' of the translation initiation site. Northern blot analysis of human skeletal muscle RNA with a human cRNA probe detected a major mRNA of approximately 4.0 kb. Transient overexpression in COS cells verified that a heat-stable inhibitor of protein kinase was produced by he human PKI cDNA, and protein extracts from the transfected COS cells inhibited both the C alpha and C beta isoforms of the PKA catalytic subunit with equal efficacy. Functional expression of the human PKI protein was further studied by assaying the ability of PKI expression vectors to inhibit PKA catalytic subunit stimulation of transcription from the human enkephalin promoter. In these studies, elimination of a conserved alternative translation start site in the 5' untranslated region of PKI was shown to potentiate the inhibitory activity of the PKI expression vector.


Asunto(s)
Proteínas Portadoras/genética , Péptidos y Proteínas de Señalización Intracelular , Inhibidores de Proteínas Quinasas , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Regulación de la Expresión Génica , Humanos , Ratones , Datos de Secuencia Molecular , Plásmidos , Biosíntesis de Proteínas , Conformación Proteica , Proteínas Recombinantes , Secuencias Reguladoras de Ácidos Nucleicos , Homología de Secuencia de Ácido Nucleico , Transcripción Genética , Transfección
8.
Mol Endocrinol ; 8(8): 970-82, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7997238

RESUMEN

The role of the cAMP-dependent kinase (AK) in neurotransmission was investigated by genetic alteration of AK subunit expression in AtT-20 clonal pituitary cells. We characterized and compared wild-type [AK(wt)] cells and two clones with different AK activities. The first stably expresses a gene for a mutant AK regulatory subunit (RI) that does not bind cAMP [AK(-)]; the second stably expresses a gene for the catalytic subunit (C) of AK [AK(+)]. Western blot analysis of RI and C subunit expression showed increased expression of both subunits in AK(+) and AK(-) cells relative to AK(wt), with the transfection-induced expression of one subunit producing a compensatory increase in the expression of the other. The basal AK activities varied among the cell types, with AK(+) cells possessing 3-fold higher basal AK activity than AK(wt) cells, and AK(-) cells possessing half the AK activity of AK(wt) cells. Preincubation of cultures with 300 microM 8-(4-chlorophenylthio)-cAMP increased AK activity approximately 4-fold in AK(wt) and AK(+) cells, but was without effect in AK(-) cells. Subsequent addition of 1 microM cAMP in vitro increased AK activity an additional 2- to 3-fold in all cell types. The higher basal AK activity found in AK(wt) and AK(+) cells was associated with larger whole cell calcium currents (approximately 43% and approximately 75% larger than in AK(-) cells, respectively) and faster rates of current rundown. The currents from each cell line had similar voltage-dependent and pharmacological properties, however, and [3H]PN200-110 binding was similar among the cell types. Maximal currents were evoked at clamp potentials of 0-10 mV; currents were inactivated approximately 30% in the steady state at holding potentials of -40 mV compared to -80 mV, and currents were reduced approximately 45% in the presence of nifedipine at -40 mV, but were insensitive to omega-conotoxin GVIA. AK(wt) and AK(+) cells also had higher basal and cAMP-stimulated release of beta-endorphin; control rates were approximately 50% greater, but stimulated rates were approximately 400% greater compared to those in AK(-) cells. We conclude that a greater number of calcium channels were activated by depolarization in the phosphorylated state, that current rundown was largely due to dephosphorylation, and that activation of calcium channels was coupled to the release of beta-endorphin.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Canales de Calcio/fisiología , Calcio/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/genética , Neoplasias Hipofisarias/patología , betaendorfina/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Sitio Alostérico , Animales , Sitios de Unión , Canales de Calcio/efectos de los fármacos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Proteínas de Unión al GTP/metabolismo , Ratones , Nifedipino/farmacología , Péptidos/farmacología , Fosforilación , Procesamiento Proteico-Postraduccional , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas , omega-Conotoxina GVIA
9.
Mol Endocrinol ; 5(7): 921-30, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1658633

RESUMEN

Cyclic AMP regulates a variety of cellular responses through activation of the catalytic subunit of cAMP-dependent protein kinase. The cDNAs for two protein isoforms of the catalytic subunit, C alpha and C beta, were placed into expression vectors, and their ability to stimulate cAMP-dependent transcription of the human enkephalin promoter was examined in transiently transfected CV-1 cells. Expression vectors for C alpha and C beta that were directed by the human cytomegalovirus promoter produced up to 350- and 200-fold increases in chloramphenicol acetyltransferase activity, respectively, when cotransfected with the ENKAT-12 reporter plasmid. Transcriptional activation was shown to be dependent upon functional kinase activity by point mutations in catalytic subunit vectors which eliminated activation. Transcriptional activation by C alpha and C beta was eliminated when the cAMP response elements (CREs) were deleted from the native enkephalin promoter, but activation was recovered when this region was replaced with an oligonucleotide containing two copies of the somatostatin CRE consensus TGACGTCA. C alpha expression vectors were found to produce 2-fold greater transcriptional activation than C beta expression vectors. These results were most likely due to the cellular kinase activity produced by the catalytic subunit expression vectors and did not appear to be dependent on CRE motif or substrate specificity. In vitro mutagenesis indicates that neither C alpha nor C beta requires N-terminal myristylation for transcriptional activation, but threonine-197 is critical to subunit function.


Asunto(s)
AMP Cíclico/farmacología , Encefalinas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Regiones Promotoras Genéticas , Proteínas Quinasas/farmacología , Secuencia de Bases , Cloranfenicol O-Acetiltransferasa/genética , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Citomegalovirus/genética , Proteínas de Unión al ADN/farmacología , Humanos , Datos de Secuencia Molecular , Mutagénesis , Plásmidos , Transcripción Genética/efectos de los fármacos , Transfección
10.
Mol Endocrinol ; 4(10): 1488-96, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2178216

RESUMEN

Prodynorphin is one of three endogenous opioid peptide genes expressed in testis. Through the use of cell fractionation procedures and Northern blot analysis, Sertoli cells were found to be the primary site of prodynorphin mRNA synthesis in rat testis. In situ hybridization of a prodynorphin cRNA probe to fixed adult tissue confirmed this result. Treatment of primary cultures of rat Sertoli cells with a cAMP analog, 8-(4-chlorophenylthio)cAMP, resulted in a transient 5.6-fold increase in steady state prodynorphin mRNA levels relative to those in control cells. This increase was maximal at 48 h of treatment, after which mRNA levels gradually declined. Treatment of Sertoli cells with cAMP analogs resulted in concurrent 2.6-fold decreases in sulfated glycoprotein-2 mRNA levels. Culture medium from Sertoli cells showed a 3.1-fold increase in secreted dynorphin immunoreactivity after treatment with 8-(4-chlorophenylthio)cAMP. Chromatographic analysis indicates that the majority of the immunoreactive dynorphin peptide synthesized in Sertoli cells is present as high mol wt species, with some processing to bioactive peptides.


Asunto(s)
AMP Cíclico/análogos & derivados , Encefalinas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Chaperonas Moleculares , Precursores de Proteínas/genética , ARN Mensajero/metabolismo , Células de Sertoli/metabolismo , Testículo/metabolismo , Animales , Bucladesina/farmacología , Células Cultivadas , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Cromatografía , Clusterina , AMP Cíclico/farmacología , Encefalinas/metabolismo , Glicoproteínas/genética , Cinética , Masculino , Hibridación de Ácido Nucleico , Precursores de Proteínas/metabolismo , ARN Mensajero/análisis , Ratas , Tionucleótidos/farmacología , Distribución Tisular
11.
J Clin Endocrinol Metab ; 83(2): 410-4, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9467549

RESUMEN

This prospective, randomized, double blind, parallel study was undertaken to elucidate further the potential mechanisms through which estrogens could promote the formation of cholesterol gallstones and to compare the impact of nonoral (transdermal) and oral estrogens on serum, hepatic, and biliary markers of estrogen action. Ninety-seven postmenopausal women were randomized to receive either transdermal estradiol (E2; 0.1 mg every 3.5 days; n = 48) or oral conjugated equine estrogens (1.25 mg every day; n = 49) for 8 weeks. Blood samples were drawn, and bile samples were obtained by cholecystokinin-stimulated duodenal drainage before and after 8 weeks of estrogen administration. The main outcome measures included serum FSH, LH, E2, estrone, estrone sulfate, sex hormone-binding globulin, lipid profiles, biliary cholesterol saturation index, cholesterol nucleation time, presence of cholesterol crystals in bile, as well as biliary arachidonate, PGE2, and mucous glycoproteins. Estrogens administered by both routes increased circulating estrogens and resulted in similar suppression of both gonadotropins. Sex hormone-binding globulin was clearly increased, and the changes in serum lipids were more pronounced with oral conjugated equine estrogens than with transdermal E2. The biliary cholesterol saturation index was significantly increased compared to the baseline values with both transdermal E2 (1.08 +/- 0.04 vs. 1.00 +/- 0.03; mean change, 8%) and oral conjugated equine estrogens (1.04 +/- 0.03 vs. 0.99 +/- 0.03; mean change, 6%); however, there was no difference between the treatments. The number of patients with cholesterol crystals detected in bile was similar after both estrogen regimens. Transdermal and oral estrogens decreased nucleation time in vitro, increased arachidonate and PGE2 levels, and minimally raised total glycoprotein concentrations. In conclusion, transdermal and oral estrogens exerted comparable nonhepatic effects, as evidenced by similar reductions of gonadotropin levels, but oral therapy exhibited substantially greater actions on hepatic markers of estrogen action. Both transdermal E2 and oral conjugated equine estrogens significantly elevated the biliary cholesterol saturation index and reduced the nucleation time. These results suggest that estrogens at the doses studied could promote gallstone formation by alteration of biliary lipids and cholesterol nucleation time that have been incriminated in this process.


Asunto(s)
Biomarcadores , Colelitiasis/inducido químicamente , Estrógenos/administración & dosificación , Estrógenos/efectos adversos , Posmenopausia , Administración Cutánea , Adulto , Anciano , Animales , Bilis/metabolismo , Colesterol/metabolismo , Cristalización , Método Doble Ciego , Femenino , Caballos , Humanos , Lípidos/sangre , Persona de Mediana Edad , Estudios Prospectivos
12.
Invest Ophthalmol Vis Sci ; 41(9): 2766-73, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10937596

RESUMEN

PURPOSE: To examine the expression of the major isoforms of cyclic guanosine monophosphate (cGMP)-dependent protein kinase (cGK) in mouse eye. METHODS: Immunohistochemical localization of cGMP in mouse eye cryosections was performed using an anti-cGMP antibody, followed by visualization with indirect fluorescence microscopy. The presence of types Ialpha, Ibeta, and II cGK mRNAs in mouse eye extracts was determined initially by RNase protection analysis. Further localization of cGK I and II mRNAs on cryosections was accomplished by in situ hybridization using digoxigenin-labeled cRNA probes and an alkaline phosphatase-conjugated anti-digoxigenin antibody. Finally, cGK I protein was localized to subcellular areas within the retina using an anti-cGK I-specific primary antibody. RESULTS: In initial immunohistochemical experiments cGMP was present in numerous regions and layers within the eye and retina. Subsequent RNase protection studies demonstrated that cGK Ialpha, Ibeta, and II mRNAs were present in mouse eye and that type Ibeta mRNA were 6.6 and 30 times more abundant than type Ialpha and type II, respectively. By in situ hybridization, cGK I mRNA was localized to photoreceptor inner segments and the ganglion cell and inner nuclear layers of the retina, and lesser amounts were found in the ciliary epithelium, lens, and cornea. The cGK II mRNA expression pattern was similar but not identical with that of cGK I. Finally, within the retina, cGK I protein was most abundant in the inner plexiform layer, with significant amounts in ganglion cells and photoreceptor inner segments as well. CONCLUSIONS: The presence of these cGK isoforms in discrete areas throughout the eye suggests multiple roles for the cGMP-dependent signal transduction system in the regulation of physiologic and pathologic ocular processes.


Asunto(s)
Proteínas Quinasas Dependientes de GMP Cíclico/metabolismo , Ojo/enzimología , Animales , Western Blotting , Proteínas Quinasas Dependientes de GMP Cíclico/genética , Técnica del Anticuerpo Fluorescente Indirecta , Hibridación in Situ , Isoenzimas/genética , Isoenzimas/metabolismo , Ratones , Microscopía Fluorescente , Plásmidos , ARN Mensajero/metabolismo
13.
Menopause ; 7(3): 162-7, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10810961

RESUMEN

OBJECTIVE: To examine the role of estrogen replacement therapy on the development of gallbladder disease in postmenopausal women. DESIGN: Systematic review of the English literature was conducted. All studies that addressed the association between hormone replacement therapy and gallbladder disease published from 1970 to the present were reviewed. RESULTS: Seven observational studies, two clinical trials, two case series, and one nonrandomized and three randomized investigations were reviewed. The results of each study were reported and analyzed. CONCLUSIONS: Estrogen replacement therapy in postmenopausal women increased the chances for gallstone formation.


Asunto(s)
Terapia de Reemplazo de Estrógeno/efectos adversos , Enfermedades de la Vesícula Biliar/etiología , Posmenopausia , Bilis/efectos de los fármacos , Colelitiasis/química , Colelitiasis/etiología , Colesterol/análisis , Femenino , Humanos , Factores de Riesgo
14.
Obstet Gynecol ; 82(4 Pt 2 Suppl): 687-9, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8378013

RESUMEN

BACKGROUND: Hepatic rupture during pregnancy has a high rate of maternal and fetal mortality. Most cases occur as a complication of severe pregnancy-induced hypertension, and maternal survival has been highest in patients managed with conservative surgical therapy. CASE: A woman in late pregnancy experienced hepatic rupture associated with cocaine use. She underwent emergency cesarean delivery and was treated with topical hemostatic agents, perihepatic packing, and hepatic artery embolization. Reexploration with perihepatic packing was performed three times during the first 48 hours after delivery to control hepatic hemorrhage. Vasopressor support, blood product replacement, and prolonged assisted ventilation were used, and the patient was discharged on hospital day 42. CONCLUSION: Liver damage may result from the potent vasoconstrictor property of cocaine, leading to vasospasm and ischemia. Conservative surgical management of hepatic rupture and supportive measures resulted in maternal survival.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Cocaína/efectos adversos , Complicaciones del Embarazo/inducido químicamente , Adulto , Femenino , Humanos , Embarazo , Rotura Espontánea
15.
Peptides ; 4(5): 651-6, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6318201

RESUMEN

Opioid peptides are synthesized in the form of large precursors, which contain the information for more than one biologically active peptide. Using recombinant DNA technology, three opioid precursors have been sequenced: pro-opiomelanocortin (POMC), proenkephalin and prodynorphin. Analysis of the structures of these three precursors and their corresponding genes show striking similarities suggesting a common evolutionary mechanism. Regulation of POMC gene expression has been analyzed in different rat tissues. Detection of POMC mRNA in brain tissues supports the hypothesis that ACTH and endorphin peptides are synthesized in these tissues. Quantitation of POMC mRNA levels in pituitaries of rats subjected to adrenalectomy and glucocorticoid treatment shows that the feedback effect of the glucocorticoids occurs at the level of the rate of transcription of POMC mRNA.


Asunto(s)
Encéfalo/metabolismo , ADN Recombinante/metabolismo , Endorfinas/genética , Encefalinas/genética , Genes , Hormonas Adenohipofisarias/genética , Precursores de Proteínas/genética , Adrenalectomía , Hormona Adrenocorticotrópica/genética , Animales , Secuencia de Bases , Clonación Molecular , ADN/genética , Dexametasona/farmacología , Humanos , Hibridación de Ácido Nucleico , Adenohipófisis/efectos de los fármacos , Adenohipófisis/metabolismo , Proopiomelanocortina , ARN Mensajero/genética , Ratas
16.
Brain Res ; 535(2): 214-20, 1990 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-1963568

RESUMEN

We studied the effects of ATP-gamma-S on the T, N and L calcium current components of nodose ganglion neurons using the whole cell variation of the patch clamp technique. ATP-gamma-S can serve as a phosphate donor in kinase-mediated reactions, the donated phosphate group being resistant to the action of phosphatases. We therefore compared the effect of ATP-gamma-S to that of the catalytic subunit of the cyclic AMP-dependent protein kinase (AK-C), included in the recording pipette with 5 mM ATP. AK-C (50 micrograms/ml) had no effect on the T current, and caused a approximately 30% increase in currents containing the N and L components during a 20-min recording, as compared to a approximately 45% decrease in control currents. In contrast, in the presence of 2.5 mM ATP-gamma-S, T currents declined approximately 30%, and currents containing the N and L components declined to a greater extent than control currents, about 65%. In addition, the time to peak current was increased from approximately 14 ms to approximately 40 ms. This effect of ATP-gamma-S on calcium currents was similar to that of certain neurotransmitters or GTP-gamma-S, an activator of G proteins, except that the effects of ATP-gamma-S were delayed 5-7 min relative to GTP-gamma-S. The effects of both ATP-gamma-S and GTP-gamma-S were reduced or abolished in neurons treated with pertussis toxin. We conclude that AK-C regulates neuronal calcium currents, presumably by phosphorylation of channels or associated proteins, and that the ATP-gamma-S-induced reduction of calcium currents cannot be due to its serving as a phosphate donor for endogenous AK.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Adenosina Trifosfato/análogos & derivados , Canales de Calcio/efectos de los fármacos , Proteínas de Unión al GTP/fisiología , Neuronas/metabolismo , Proteínas Quinasas/metabolismo , Adenosina Trifosfato/farmacología , Animales , Potenciales Evocados/efectos de los fármacos , Neuronas/efectos de los fármacos , Ganglio Nudoso/citología , Ganglio Nudoso/efectos de los fármacos , Ganglio Nudoso/metabolismo , Toxina del Pertussis , Ratas , Factores de Virulencia de Bordetella/farmacología
17.
Fertil Steril ; 58(6): 1191-8, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1459270

RESUMEN

OBJECTIVE: To study the direct effects of progesterone (P) and its antagonist RU486 (mifepristone) on sperm hyperactivation (HA) and acrosome reaction. DESIGN: Prospective evaluation of semen samples incubated in capacitation media with P and/or RU486. SETTING: University-affiliated tertiary care center. PATIENTS: Normal healthy volunteers. INTERVENTIONS: Semen samples were incubated in media with P or RU486 alone or in combination, and aliquots were taken at 10 minutes, 1, 5, and 24 hours for HA analyses by computer-aided sperm analysis system, and at 0, 5, and 24 hours for assessment of acrosome reaction by fluorescein-labeled Pisum sativum (pea) agglutinin. MAIN OUTCOME MEASURES: HA and acrosome reaction. RESULTS: Sperm HA was significantly increased at 10 minutes by P both at 10(-7) M (9.27 +/- 1.59%; mean +/- SEM) and 10(-6) M (9.39 +/- 1.94%) when compared with untreated spermatozoa (5.62 +/- 1.59%). The stimulatory effect of P on sperm HA was transient because this was not observed after 1, 5, and 24 hours of incubation. The antiprogesterone RU486 (10(-6) M) alone had no effect and did not abolish the stimulatory effect of P on HA. The %HA was further enhanced by the addition of RU486 at 10(-6) M to P at 10(-7) M (12.43 +/- 3.31%) or P at 10(-6) M (13.52 +/- 4.10%); however, this effect was not significantly different from P alone. Coincubation of P or RU486 with spermatozoa during capacitation did not stimulate the acrosome reaction in the concentrations tested. CONCLUSION: Progesterone directly stimulates human sperm HA transiently. Progesterone has no significant effect on acrosome reaction in capacitating spermatozoa. The effects of P are rapid and not counteracted by RU486, suggesting that the mechanism of action of P may not be mediated by specific P nuclear receptors.


PIP: Reproductive endocrinologists at the University of California, Los Angeles Medical Center, obtained semen samples from healthy volunteers to examine the direct effects of progesterone and the antiprogesterone RU-486 on sperm hyperactivation and acrosome reaction, which they hoped would elucidate progesterone's mechanism of action. They used progesterone concentrations which match those of the female reproductive tract. Progesterone induced a considerable increase in sperm hyperactivation at 10 millionths M and 1 millionth M after 10 minutes (9.27% and 9.39% vs. 5.62% for untreated spermatozoa; p .05). The ability of progesterone to increase sperm hyperactivation was only temporary, however. In fact, progesterone had no effect at 1, 5, and 24 hours. RU-486 alone did not affect sperm hyperactivation. Addition of RU-486 at 1 millionth M to progesterone further did strengthen the stimulatory effect, however, but it was not significant (13.52% vs. 9.39%). When progesterone or RU-486 were coincubated with spermatozoa during the process by which they become able to fertilize the ovum after they are at the ampullar portion of the uterine tube, neither chemical stimulated the acrosome reaction, regardless of the concentration. These results indicated that progesterone can only directly stimulate sperm hyperactivation temporarily and rapidly (within about 10 minutes) and does not influence acrosome reaction during capacitation. They also demonstrated that RU-486 cannot counteract progesterone. Thus, specific progesterone receptors do not mediate progesterone's mechanism of action.


Asunto(s)
Acrosoma/efectos de los fármacos , Acrosoma/fisiología , Mifepristona/farmacología , Progesterona/farmacología , Motilidad Espermática/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Masculino , Mifepristona/administración & dosificación , Progesterona/administración & dosificación , Progesterona/antagonistas & inhibidores , Estudios Prospectivos , Capacitación Espermática/fisiología
18.
Fertil Steril ; 60(6): 1076-81, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8243689

RESUMEN

OBJECTIVE: To determine the applicability of flow cytometry to assess human sperm acrosome reaction. DESIGN: Prospective evaluation of semen samples incubated overnight for the development of spontaneous acrosome reaction or exposed to the calcium ionophore A23187 (5 microM) for 3 hours for induction of the acrosome reaction. SETTING: University-affiliated tertiary care center. PATIENTS: Normal healthy volunteers. INTERVENTIONS: The spermatozoa were stained with fluorescein isothiocyanate (FITC)-labeled pea agglutinin. The labeled samples were assessed visually and also subjected to analytic flow cytometry and fluorescence-activated cell sorting. MAIN OUTCOME MEASURES: Acrosome reaction assessed visually and by flow cytometry. RESULTS: Flow cytometric analysis showed a single peak of FITC fluorescence in the washed semen samples. A second peak of lower FITC fluorescence intensity was noted after overnight incubation or exposure to A23187, suggesting loss of fluorescence, which indicated the occurrence of the acrosome reaction. There was a statistically significant correlation between the assessment by the two methods (n = 41). However, although the mean difference between the methods was small (2.49%), the difference between the two methods for each individual sample can vary between -24% to +29%. When the sperm cells were subjected to cell sorting based on green fluorescence intensity, reanalysis and visual scoring verified that the low intensity peak contained a majority of acrosome-reacted spermatozoa (77.52% +/- 2.39%). CONCLUSION: These results validated the flow cytometric method for assessment of acrosome-reacted spermatozoa. Although flow cytometry is more objective and less time consuming when many samples are assessed at the same time, the visual method remains a useful and practical procedure in the clinical andrology laboratory.


Asunto(s)
Acrosoma/fisiología , Citometría de Flujo , Lectinas de Plantas , Acrosoma/efectos de los fármacos , Calcimicina/farmacología , Separación Celular , Fluoresceína-5-Isotiocianato , Colorantes Fluorescentes , Humanos , Lectinas , Masculino , Estudios Prospectivos , Espermatozoides/citología
19.
Fertil Steril ; 76(5): 957-61, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11704117

RESUMEN

OBJECTIVE: To assess the effect of ibuprofen, a nonspecific inhibitor of prostaglandin synthesis, on ovulation. DESIGN: Prospective, randomized, double-blind, placebo-controlled cross-over study. SETTING: University Medical Center. PATIENT(S): Twelve normally cycling women between ages 20 and 40. INTERVENTION(S): Subjects were randomized to either oral ibuprofen (800 mg) or placebo three times per day, beginning when the maximum diameter of the leading follicle reached 16 mm by ultrasound, and continuing for 10 days total. The second cycle was a washout period, and in the third cycle, the subjects were crossed over to the alternate regimen from the first cycle. The probability of delayed follicular collapse was determined using the binomial distribution, and changes in P levels were compared using the paired t test. MAIN OUTCOME MEASURE(S): Urinary LH surge, follicular collapse by serial transvaginal ultrasonography, and serum midluteal P levels. RESULT(S): Eleven of 12 subjects detected an LH surge with both ibuprofen and placebo. Five of 11 women demonstrated a >or=2-day increase in time interval from detection of the LH surge to follicular collapse, and 3 of those 5 had been randomized to ibuprofen. This represents a 27% (3 of 11; 95% confidence limits: 1%, 53%) rate of delay for follicular collapse for ibuprofen. There was no difference in average midluteal P levels for ibuprofen or placebo. CONCLUSION(S): If ibuprofen inhibits follicular collapse, this effect is seen in a small group of study subjects, and this information should be clinically reassuring to patients who take nonsteroidal anti-inflammatory drugs. Serum midluteal P levels were unaffected by administration of ibuprofen.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Ibuprofeno/farmacología , Ovulación/efectos de los fármacos , Adulto , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Folículo Ovárico/diagnóstico por imagen , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Estudios Prospectivos , Factores de Tiempo , Ultrasonografía
20.
J Androl ; 17(3): 288-92, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8792219

RESUMEN

This study was undertaken to compare a new fluorescent stain-based computer-assisted semen analysis (CASA) system (IDENT) for determining human sperm concentration to the manual hemacytometric method and to conventional CASA (CASA-CONV). Normal healthy semen donors as well as patients provided samples that were evaluated for sperm concentration with the CASA-IDENT method, the hemacytometer method, and CASA-CONV. Each field was examined visually to determine the sources of overcounting and undercounting for the two CASA methods. Four ranges of sperm concentration were examined: 0-10, > 10-30, > 30-100, and > 100 x 10(6)/ml. The main outcome measures were sperm concentration, debris counted as sperm, and missed sperm. Our results showed that significantly more debris was counted as sperm and more sperm were missed with CASA-CONV than CASA-IDENT. As the sperm density increased, so did the number of counting errors for the CASA-CONV system. The error rate was much greater using CASA-CONV (12.1 +/- 42.2%) than with CASA-IDENT (0.4 +/- 0.7%) when compared to hemacytometer counts (P = 0.068). We conclude that the CASA-IDENT method of sperm counting is highly accurate and less time-consuming when compared to the hemacytometer method. There are significant differences in the amount of debris counted as sperm and number of missed sperm between CASA-CONV and CASA-IDENT with varying sperm density. With both parameters, the counts are more accurate using the CASA-IDENT method.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Semen/citología , Recuento de Espermatozoides/métodos , Bencimidazoles , Estudios de Evaluación como Asunto , Colorantes Fluorescentes , Humanos , Masculino , Coloración y Etiquetado
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