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1.
iScience ; 27(3): 109237, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38433896

RESUMO

Ductal progenitor-like cells are a sub-population of ductal cells in the adult human pancreas that have the potential to contribute to regenerative medicine. However, the microenvironmental cues that regulate their activation are poorly understood. Here, we establish a 3-dimensional suspension culture system containing six defined soluble factors in which primary human ductal progenitor-like and ductal non-progenitor cells survive but do not proliferate. Expansion and polarization occur when suspension cells are provided with a low concentration (5% v/v) of Matrigel, a sarcoma cell product enriched in many extracellular matrix (ECM) proteins. Screening of ECM proteins identified that collagen IV can partially recapitulate the effects of Matrigel. Inhibition of integrin α1ß1, a major collagen IV receptor, negates collagen IV- and Matrigel-stimulated effects. These results demonstrate that collagen IV is a key ECM protein that stimulates the expansion and polarization of human ductal progenitor-like and ductal non-progenitor cells via integrin α1ß1 receptor signaling.

2.
Stem Cells ; 42(4): 385-401, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38206366

RESUMO

Pancreatic ductal progenitor cells have been proposed to contribute to adult tissue maintenance and regeneration after injury, but the identity of such ductal cells remains elusive. Here, from adult mice, we identify a near homogenous population of ductal progenitor-like clusters, with an average of 8 cells per cluster. They are a rare subpopulation, about 0.1% of the total pancreatic cells, and can be sorted using a fluorescence-activated cell sorter with the CD133highCD71lowFSCmid-high phenotype. They exhibit properties in self-renewal and tri-lineage differentiation (including endocrine-like cells) in a unique 3-dimensional colony assay system. An in vitro lineage tracing experiment, using a novel HprtDsRed/+ mouse model, demonstrates that a single cell from a cluster clonally gives rise to a colony. Droplet RNAseq analysis demonstrates that these ductal clusters express embryonic multipotent progenitor cell markers Sox9, Pdx1, and Nkx6-1, and genes involved in actin cytoskeleton regulation, inflammation responses, organ development, and cancer. Surprisingly, these ductal clusters resist prolonged trypsin digestion in vitro, preferentially survive in vivo after a severe acinar cell injury and become proliferative within 14 days post-injury. Thus, the ductal clusters are the fundamental units of progenitor-like cells in the adult murine pancreas with implications in diabetes treatment and tumorigenicity.


Assuntos
Células Acinares , Ductos Pancreáticos , Camundongos , Animais , Pâncreas , Células-Tronco , Diferenciação Celular
3.
JBRA Assist Reprod ; 27(3): 355-359, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36749808

RESUMO

OBJECTIVE: Is self-detection of the endogenous LH surge using a urine testing a reliable method to confirm a successful gonadotropin-releasing hormone agonist (GnRHa) trigger in IVF cycles? METHODS: Prospective observational study including a total of 103 oocyte donation cycles between November 2019 and January 2020. Urine LH testing (Akralab SL, Spain, cut-of value 30 mIU/mL) was performed at home in samples from the first micturition in the morning after the GnRHa trigger and a picture of the result was sent to the nurse coordinator; this information was concealed and only disclosed after oocyte aspiration. RESULTS: From the total group, two cycles were excluded. A total of 101 oocyte donors performed the LH urine testing, all proceeded to oocyte aspiration and were included in final analysis. A total of 85 (84.2%) had a positive LH test and an uneventful oocyte retrieval with good retrieval rates (false positive rate: 0%). A total of 16 had a negative LH test (15.8%) and had a good oocyte retrieval rates (false negative rate: 15.8%). There were no cases of empty follicle syndrome. CONCLUSIONS: Due to a high false negative rate, self-testing of endogenous LH release using a LH urine test when performed approximately 12-hours after triggering does not seem to be a reliable method to predict a suboptimal response to gonadotropin-releasing hormone.


Assuntos
Hormônio Luteinizante , Indução da Ovulação , Humanos , Indução da Ovulação/métodos , Fertilização in vitro/métodos , Hormônio Liberador de Gonadotropina , Oócitos/fisiologia , Gonadotropina Coriônica
4.
AJOG Glob Rep ; 2(4): 100103, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36275401

RESUMO

BACKGROUND: The factors associated with embryo aneuploidy have been extensively studied. Mostly maternal age and to a lesser extent male factor and ovarian stimulation have been related to the occurrence of chromosomal alterations in the embryo. On the other hand, the main factors that may increase the incidence of embryo mosaicism have not yet been established. OBJECTIVE: This study aimed to establish a machine learning model that would allow prediction of aneuploidies and mosaicism in embryos conceived via in vitro fertilization, and thus help to determine which variables are associated with these chromosomal alterations. STUDY DESIGN: The study design was observational and retrospective. A total of 6989 embryos from 2476 cycles of preimplantation genetic testing for aneuploidies were included (January 2013 to December 2020). The trophoectoderm biopsies on day-5, -6, or -7 blastocysts were analyzed by preimplantation genetic testing for aneuploidies (PGT-A). The different maternal, paternal, couple, embryo, and in vitro fertilization cycle characteristics were recorded in a database (22 predictor variables) from which predictive models of embryo aneuploidy and mosaicism were developed; 16 different unsupervised classification machine learning algorithms were used to establish the predictive models. RESULTS: Two different predictive models were performed: one for aneuploidy and the other for mosaicism. The predictor variable was of multiclass type because it included the segmental- and whole-chromosome alteration categories. The best predicting models for both aneuploidies and mosaicism were those obtained from the Random Forest algorithm. The area under ROC curve (AUC) value was 0.792 for the aneuploidy explanatory model and 0.776 for mosaicism. The most important variable in the final aneuploidy model was maternal age, followed by paternal and maternal karyotype and embryo quality. In the predictive model of mosaicism, the most important variable was the technique used in preimplantation genetic testing for aneuploidies and embryo quality, followed by maternal age and day of biopsy. CONCLUSION: It is possible to predict embryo aneuploidy and mosaicism from certain characteristics of the patients and their embryos.

5.
Syst Biol Reprod Med ; 67(4): 270-280, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34053384

RESUMO

The aim of our study was to investigate the effect of maternal and embryo MTHFR C677T and A1298C polymorphisms on embryo aneuploidies and mosaicism and the correlation between these genetic variants in transferred euploid embryos and IVF outcomes. MTHFR genotype was analyzed in 77 women who performed an IVF/ICSI cycle with PGT-A. Moreover, to evaluate the effect of embryo MTHFR polymorphisms on embryo aneuploidies and mosaicism, the MTHFR genotype was analyzed in 191 biopsied embryos from the PGT-A cycles of these patients. Additionally, 218 DNA samples from trophectoderm biopsies belonging to a different group of patients were also genotyped. MTHFR polymorphisms were analyzed in a total amount of 409 trophectoderm samples. The main parameters analyzed were embryo aneuploidy and mosaicism rates. Finally, the IVF outcomes of 241 single euploid embryo transfers were assessed and compared between different MTHFR embryo genotypes. The aneuploidy rates were similar in embryos from homozygous normal women and women with at least one mutated allele (54.7% vs. 30.2% in 677C>T and 37.8% vs. 42.7% in 1298A>C). Furthermore, no differences were observed in the mosaicism rate (24.0% vs. 13.8% in 677C>T and 17.1% vs. 17.3% in 1298A>C). A similar analysis was performed, taking into account the embryo genotype results. No differences in aneuploidy rate were observed between the study groups. The only significant difference was the mosaicism rate among 677C>T genotype (13.5% in 677CC group vs. 5.4% in 677CT/TT; p = 0.019). Implantation rate, biochemical and clinical miscarriage rates, and ongoing pregnancy rate were compared between different embryo genotypes, and no statistically significant differences were found. In conclusion, the maternal MTHFR genotype did not influence embryo chromosomal abnormalities. Moreover, the embryo MTHFR genotype was not associated with embryo aneuploidy or IVF outcomes such as implantation, pregnancy loss, and ongoing pregnancy when euploid embryos were transferred.Abbreviations: MTHFR: methylenetetrahydrofolate reductase; IVF: in vitro fertilization; PGT-A: preimplantation genetic testing for aneuploidies; SAM: S-adenosyl methionine; SNP: single nucleotide polymorphism; SPSS: Statistical Package for Social Sciences; RIF: recurrent implantation failure; RPL: recurrent pregnancy loss; hCG: human chorionic gonadotropin; PBS: phosphate buffered saline; CGH: comparative genomic hybridization; NGS: next generation sequencing.


Assuntos
Aborto Habitual , Metilenotetra-Hidrofolato Redutase (NADPH2) , Diagnóstico Pré-Implantação , Aborto Habitual/genética , Aneuploidia , Hibridização Genômica Comparativa , Feminino , Fertilização in vitro , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo Genético , Gravidez
6.
Reprod Biomed Online ; 42(3): 555-563, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33454211

RESUMO

RESEARCH QUESTION: Are discordances in non-invasive preimplantation genetic testing for aneuploidies (niPGT-A) results attributable to the technique used for chromosomal analysis? DESIGN: A prospective blinded study was performed (September 2018 to December 2019). In total 302 chromosomal analyses were performed: 92 trophectoderm PGT-A biopsies and their corresponding spent embryo culture medium (SCM) evaluated by two methods (n = 184), negative controls (n = 8), and trophectoderm and inner cell mass biopsies from trophectoderm-aneuploid embryos (n = 18). Trophectoderm analyses were carried out using Veriseq (Illumina), and SCM was analysed using Veriseq and NICS (Yikon). RESULTS: Genetic results were obtained for 96.8% of trophectoderm samples versus 92.4% for both SCM techniques. The mosaicism rate was higher for SCM regardless of the technique used: 30.4% for SCM-NICS and 28.3% for SCM-Veriseq versus 14.1% for trophectoderm biopsies (P = 0.013, P = 0.031, respectively). No significant differences in diagnostic concordance were seen between the two SCM techniques (74.6% for SCM-NICS versus 72.3% for SCM-Veriseq; P = 0.861). For embryos biopsied on day 6, these rates reached 92.0% and 86.5%, respectively. On reanalysing trophectoderm-aneuploid embryos, the discrepancies were shown to be due to maternal DNA contamination (55.6%; 5/9), embryo mosaicism (22.2%; 2/9) and low resolution in SCM-NICS (11.1%; 1/9) and in both SCM techniques (11.1%; 1/9). CONCLUSIONS: This is the first study evaluating the consistency of different chromosomal analysis techniques for niPGT-A. In conclusion, the diagnostic concordance between PGT-A and niPGT-A seems independent of the technique used. Optimization of culture conditions and medium retrieval provides a potential target to improve the reliability of niPGT-A.


Assuntos
Aneuploidia , Análise Citogenética/métodos , Diagnóstico Pré-Implantação/métodos , Adulto , Biópsia , Meios de Cultivo Condicionados/análise , Técnicas de Cultura Embrionária , Feminino , Humanos , Estudos Prospectivos , Trofoblastos/patologia
7.
JBRA Assist Reprod ; 25(1): 122-127, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-32969212

RESUMO

OBJECTIVE: Monozygotic twinning incidence following preimplantation genetic testing in embryos at cleavage-stage does not appear to increase; however, data regarding the possible impact of the blastocyst-stage preimplantation genetic testing is lacking. We compared the incidence of monozygotic twinning in preimplantation genetic testing cycles performed at the blastocyst-stage, versus cycles without PGT, following single embryo transfer. METHODS: In this retrospective cohort study, we analyzed the incidence of twin pregnancies in patients undergoing intracytoplasmic sperm injection and blastocyst-preimplantation genetic testing (253 cycles), versus a period-matched control population of patients undergoing intracytoplasmic sperm injection and single embryo transfer without preimplantation genetic testing (606 cycles). RESULTS: The overall monozygotic twinning rate was 14/859 (1.6%) per clinical pregnancy. The incidence of zygotic splitting following intracytoplasmic sperm injection and preimplantation genetic testing was 3.5% (95% Confidence interval 1.8%-6.6%) versus 0.8% (95% Confidence interval 0.3%-1.9%) following intracytoplasmic sperm injection without preimplantation sperm injection. After adjusting for potential confounders, preimplantation genetic testing cycles were associated with an increase in the incidence of monozygotic twinning when compared to cycles without embryo biopsy (Odd ratio 3.44, 95% Confidence interval 1.05-11.27, p=0.041). CONCLUSIONS: Our findings indicate that embryo biopsy for preimplantation genetic testing performed at the blastocyst stage is associated to an increase in the incidence of monozygotic twinning. Further validation in larger sample size studies is warranted. Patients undergoing preimplantation genetic testing must receive proper counselling about the potential risks of the technique.


Assuntos
Transferência Embrionária , Gemelaridade Monozigótica , Biópsia , Blastocisto , Feminino , Humanos , Gravidez , Estudos Retrospectivos
8.
Hum Fertil (Camb) ; 23(2): 117-122, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30332901

RESUMO

Recurrent pregnancy loss (RPL; defined as the loss of three or more consecutive pregnancies) and recurrent implantation failure (RIF; when implantation is not achieved after at least three cycles of IVF) are two of the major challenges that reproductive medicine faces. Some polymorphisms have been identified as possible causes of an increased risk of these diseases. This paper studies the prevalence of the polymorphisms in p53, VEGF, IL-10, IL-11 and APOE in RIF and RPL patients that determines the risk for these pathologies. A total of 255 patients were selected (89 RPL patients, 77 RIF patients and 89 controls) and genotyped for p53-R72P; IL-11-1082-AG; VEGF-1154-AG; IL-10; APOE-R112C; APOE-R158C. Statistically significant differences were found in the prevalence of the E4 isoform (R122-R158) of the APOE gene in RPL patients (p < 0.05), and in RIF patients, the R72P polymorphism of the p53 gene and the 1154-AG of the VEGF gene showed different distribution (p < 0.05). Regarding the p53 and IL-11 studied polymorphisms, PP of p53 gene and GG of IL-11 are more prevalent in RPL patients without reaching statistical significance. In conclusion, our results suggest patients carrying variants in p53 and VEGF would be at risk of RIF, and those carrying variants in APOE gene would suffer RPL.


Assuntos
Aborto Habitual/genética , Interleucina-10/genética , Interleucina-11/genética , Polimorfismo de Nucleotídeo Único , Proteína Supressora de Tumor p53/genética , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Apolipoproteínas E/genética , Implantação do Embrião/genética , Feminino , Regulação da Expressão Gênica , Predisposição Genética para Doença , Genótipo , Humanos , Gravidez
9.
Pharmacogenet Genomics ; 29(9): 216-223, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31568130

RESUMO

OBJECTIVE: To investigate if polymorphisms of some genes involved in folliculogenesis predict ovarian response. METHODS: This prospective randomized study includes 124 egg donors genotyped for six SNPs ESR1 (rs2234693), AMHR2 (rs2002555), GDF-9 (rs10491279 and rs254286), AMH (rs10407022) and LHCBR (rs229327) genes and four STRs in ESR1 rs3138774), SHBG (rs6761), CYP19A1 (rs60271534) and AR genes (CAG repeats in exon 1). All donors followed standard ovarian stimulation protocol using a daily dose of 225 UI. The genotypes obtained were compared with the ovarian stimulation outcome. RESULTS: Regarding the number of retrieved oocytes, we found statistical differences for the ESR1 SNP and STR (19.3 ± 8.9 for TT vs 15.3 ± 6.2 for CC/CT, P = 0.027; 19.1 ± 8.3 for <17repeats vs 14.7 ± 6.2 for >17repeats, P = 0.020). Moreover, women carrying TT in the ESR1 at position c.-397T>C with ESR1 (TA)n=17 retrieved the highest number of oocytes (20.4 ± 9.3) (P = 0.001). Concerning AMHR2, we observed an association with the length of stimulation (9.1 ± 1.4 d for AA vs 9.7 ± 1.3 d for AG/GG, P = 0.021) and gonadotropin received (2050 ± 319 for AA vs 2188 ± 299 for AG/GG, P = 0.017). No significant differences were observed for the other polymorphisms (P > 0.05). CONCLUSION: The polymorphisms in ESR1 and AMHR2 genes showed a clear association with the number of retrieved oocytes and the stimulation data, respectively. Our results suggest that polymorphisms in the genes for key reproductive hormones receptors could be used to predict the ovarian response and to personalize the stimulation prior the treatment.


Assuntos
Testes Genéticos , Variação Genética , Ovário/fisiologia , Feminino , Humanos , Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores de Estrogênio/metabolismo , Adulto Jovem
10.
Pharmacogenomics ; 15(6): 885-93, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24897293

RESUMO

Effective controlled ovarian stimulation (COS) is crucial for IVF outcome. Ovarian response to follicle-stimulating hormone, however, varies widely among women undergoing ovarian stimulation. Advance identification of patients who will elicit a poor or high response to standard treatment would be of great clinical benefit for such patients. Application of pharmacogenetics to ovarian response may predict stimulation success but also help in the adjustment and design of doses prior to treatment. Different studies have examined the impact of variations in follicle-stimulating hormone receptor, biochemical pathways involved in estrogen production and action, folliculogenesis and other aspects. Recently, gene-association studies have tried to identify a number of genetic variations affecting interindividual variability in COS.


Assuntos
Ovário/metabolismo , Estrogênios/genética , Estrogênios/metabolismo , Feminino , Hormônio Foliculoestimulante/metabolismo , Variação Genética/genética , Humanos , Indução da Ovulação , Farmacogenética/métodos , Receptores do FSH/genética , Receptores do FSH/metabolismo
12.
J Assist Reprod Genet ; 31(2): 169-72, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24327010

RESUMO

PURPOSE: Investigate whether R72P on p53 gene polymorphism has a higher prevalence among women with a history of recurrent implantation failure (RIF) and pregnancy loss (RPL) and its influence in their IVF cycle outcome. MATERIAL AND METHODS: p53 polymorphism R72P has been studied in 181 women. The control group included 83 oocyte donors. In the study group 98 women were included: 44 with RIF and 54 with RPL. From the study group, 76 patients underwent IVF-cycles (55 RPL and 21 RIF). RESULTS: The frequency of PP genotypes on p53 among RIF was 11.4% compared with 18.5% for RPL and 6% in controls (p < 0.01). There were no significant differences with respect to patient characteristics. Significant differences were reported in pregnancy rate (69.4% for RR/RP and 33.3% for PP; p < 0.05), embryo implantation rate (33.3% for RR/RP and 7.3% for PP; p < 0.05) and ongoing pregnancy rate (53.1% for RR/RP and 14.3% for PP; p < 0.05) among RIF and RPL. CONCLUSIONS: This investigation reveals that in RIF and RPL patients R72P on p53 gene is more prevalent than fertile population. Moreover, patients carrying a PP genotype on p53 codon 72 will have less chance to achieve an ongoing pregnancy. This information together with some additional markers will allow development of diagnostic tests for detects risk for RIF and RPL before infertility treatment is initiated.


Assuntos
Aborto Espontâneo/genética , Implantação do Embrião/genética , Fertilização in vitro , Genes p53 , Polimorfismo Genético , Adulto , Estudos de Casos e Controles , Códon , Feminino , Frequência do Gene , Humanos , Masculino , Gravidez , Taxa de Gravidez , Falha de Tratamento
13.
Pharmacogenet Genomics ; 23(5): 262-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23470615

RESUMO

OBJECTIVE: The aim of this study was to investigate whether N680S FSHR polymorphism has a predictive value for the ovarian response to stimulation with gonadotropins and cycle outcome in our egg donor program. METHODS: The oocyte donor candidates were selected according to the Instituto Bernabeu egg donation program requirements and ASRM and ESHRE guidelines for oocyte donation. The FSHR polymorphism N680S was studied in 145 oocyte donors. All donors underwent controlled ovarian hyperstimulation (COH) (n=355) using urinary follicle-stimulating hormone in a GnRH antagonist protocol and receiving a GnRH agonist triggering. The main outcome measures were oocyte yield, days of stimulation, gonadotropin doses, biochemical pregnancy, ongoing pregnancy, and miscarriage rates. RESULTS: Significant differences were reported in the antral follicle count (16.5 ± 5.0 for NN, 14.5 ± 4.7 for NS, and 14.1 ± 3.8 for SS), number of eggs retrieved (21.5 ± 9.2 for NN, 18.5 ± 8.2 for NS, and 19.8 ± 8.9 for SS), and gonadotropin doses (2098.5 ± 639.4 IU for NN, 2023 ± 490.1 IU for NS, and 2149.5 ± 552.3 IU for SS) between the genotypes. The clinical outcome was not affected by the N680S polymorphism of the FSHR gene in the egg donors. CONCLUSION: In a population of fertile egg donors, the FSHR gene polymorphism at position 680 is associated with different ovarian responses to COH. The genotype of the FSHR gene is an important factor for determining the prognosis of the COH cycles in normo-ovulatory fertile women.


Assuntos
Doação de Oócitos , Síndrome de Hiperestimulação Ovariana/genética , Indução da Ovulação , Receptores do FSH/genética , Adulto , Feminino , Fertilização in vitro , Genótipo , Hormônio Liberador de Gonadotropina , Gonadotropinas/administração & dosagem , Humanos , Síndrome de Hiperestimulação Ovariana/patologia , Polimorfismo Genético , Gravidez , Taxa de Gravidez
15.
Acta méd. costarric ; 50(4): 248-250, oct.-dic. 2008. ilus, graf
Artigo em Espanhol | LILACS | ID: lil-581277

RESUMO

Se presenta el caso de una mujer de 52 años sedentaria y con sobrepeso, índice de masa corporal igual 28.3, que tiene, según ATP-III, las 5 características del síndrome metabólico: diabetes tipo 2, glicemia en ayunas igual 294 mg/dL, trialcilglicerol igual 162 mg/dL, HDL-colesterol igual 44 mg/dL y obesidad central, perímetro de la cintura igual 90 cm. La diabetes tipo 2 le fue diagnosticada hace 17 años, recibe medicamento para la hipertensión desde hace 7 años y presenta hipercolesterolemia, colesterol total igual 283 mg/dL, para lo que no recibe tratamiento farmacológico. A pesar de su condición, la paciente se considera saludable lo cual le impide modificar su estilo de vida y mejorar la calidad de vida lo que aumenta el costo de su tratamiento médico para el sistema de seguridad social.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Pressão Sanguínea , Diabetes Mellitus , Hipertensão/complicações , Hipertensão/psicologia , Hipertensão/terapia , Obesidade , Percepção , Costa Rica
16.
Rev. costarric. cardiol ; 9(3): 17-22, sept.-dic. 2007. ilus
Artigo em Espanhol | LILACS | ID: lil-581147

RESUMO

La obesidad es un padecimiento complejo que ha alcanzado niveles de epidemia mundial y constituye un importante riesgo de enfermedad cardiovascular. En el 2005, el 40.5 por ciento de la población adulta estadounidense era físicamente inactiva, sedentaria, un año antes la prevalencia de obesidad, en la misma población, era de 32.1 por ciento, un aumento de 37.8 por ciento en una década. Existen pocos trabajos publicados que valoran el efecto de la actividad física, AF en la pérdida inicial peso y en el mantenimiento del nuevo peso después de un período de seguimiento igual o mayor a 1 año. La evidencia indica que el efecto del gasto de energía por AF incrementa la pérdida de peso, mejora la conservación del nuevo peso durante el período de seguimiento, 2 años, disminuye la pérdida de masa magra que produce la pérdida de peso, mejora el control de la ingesta de energía y no produce un incremento compensatorio en el corto plazo en la ingesta de energía. Los programas exitosos de pérdida de peso y mantenimiento del peso perdido incluyen un aumento en la AF. Es necesario hacer estudios aleatorizados y controlados de pérdida de peso y mantenimiento del nuevo peso que incluyan aumentos en la AF antes, durante y después de la restricción de la ingesta de calorías y sus diferentes combinaciones que permita estimar la magnitud de cada efecto.


Assuntos
Humanos , Peso Corporal , Doenças Cardiovasculares , Exercício Físico , Obesidade , Esforço Físico , Fatores de Risco
17.
J Neurochem ; 95(6): 1585-96, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16238698

RESUMO

Using a yeast two-hybrid screening we report the isolation of a novel human protein, hCRELD2beta, that interacts specifically with the large cytoplasmic regions of human nicotinic acetylcholine receptor (nAChR) alpha4 and beta2 subunits, both in yeast cells and in vitro. This interaction is not detected with nAChR alpha7 and alpha3 subunits. The hCRELD2 gene encodes for multiple transcripts, likely to produce multiple protein isoforms. A previously reported one has been renamed as CRELD2alpha. Isoforms alpha and beta are expressed in all tissues examined and have the same N-terminal and central regions but alternative C-terminal regions. Both isoforms interact with the alpha4 subunit. Within this subunit the interaction was localized to the N-terminal region of the large cytoplasmic loop. The CRELD2beta protein is present at the endoplasmic reticulum where colocalized with alpha4beta2 nAChRs upon cell transfection. Immunohistochemistry experiments demonstrated the presence of CRELD2 in the rat brain at sites where alpha4beta2 receptors have been previously detected. Labeling was restricted to neuronal perikarya. Finally, CRELD2 decreases the functional expression and impairs membrane transport of alpha4beta2 nAChRs in Xenopus leavis oocytes, without affecting alpha3beta4 and alpha7 nAChR expression. These results suggest that CRELD2 can act as a specific regulator of alpha4beta2 nAChR expression.


Assuntos
Moléculas de Adesão Celular/metabolismo , Cisteína/fisiologia , Citoplasma/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Neurônios/metabolismo , Receptores Nicotínicos/metabolismo , Sequência de Aminoácidos , Northern Blotting , Western Blotting , Química Encefálica/fisiologia , Células Cultivadas , DNA Complementar/biossíntese , DNA Complementar/genética , DNA Recombinante/biossíntese , DNA Recombinante/genética , Retículo Endoplasmático/metabolismo , Biblioteca Gênica , Humanos , Imuno-Histoquímica , Microscopia Confocal , Dados de Sequência Molecular , Plasmídeos/genética , Dobramento de Proteína , Frações Subcelulares/metabolismo , Transfecção , Leveduras/genética , beta-Galactosidase/metabolismo
18.
J Biol Chem ; 278(39): 37249-55, 2003 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-12860975

RESUMO

The alpha9 subunit is a component of the neuronal nicotinic acetylcholine receptor gene superfamily that is expressed in very restricted locations. The promoter of the human gene has been analyzed in the human neuroblastoma SH-SY5Y, where alpha9 subunit expression was detected, and in C2C12 cells that do not express alpha9. A proximal promoter region (from -322 to +113) showed maximal transcriptional activity in SH-SY5Y cells, whereas its activity in C1C12 cells was much lower. Two elements unusually located at the 5'-noncoding region exhibited opposite roles. A negative element located between +15 and +48 appears to be cell-specific because it was effective in C2C12 but not in SH-SY5Y cells, where it was counterbalanced by the presence of the promoter region 5' to the initiation site. An activating element located between +66 and +79 and formed by two adjacent Sox boxes increased the activity of the alpha9 promoter about 4-fold and was even able to activate other promoters. This element interacts with Sox proteins, probably through a cooperative mechanism in which the two Sox boxes are necessary. We propose that the Sox complex provides an initial scaffold that facilitates the recruiting of the transcriptional machinery responsible for alpha9 subunit expression.


Assuntos
Regiões 5' não Traduzidas/fisiologia , Regulação da Expressão Gênica , Receptores Nicotínicos/genética , Transcrição Gênica , Regiões 5' não Traduzidas/química , Sequência de Bases , Linhagem Celular , Proteínas de Ligação a DNA/fisiologia , Proteínas de Grupo de Alta Mobilidade/fisiologia , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Subunidades Proteicas , Fatores de Transcrição SOXE , Fatores de Transcrição , Ativação Transcricional
19.
Med. interna Méx ; 15(2): 61-4, mar.-abr. 1999. tab
Artigo em Espanhol | LILACS | ID: lil-266670

RESUMO

Objetivo: analizar los resultados de la apendicectomía laparoscópica y la apendicectomía abierta para comparar y evaluar ambos procedimientos realizados por el mismo equipo médico Sede: servicio de cirugía general del Hospital Regional 1§ de octubre y practica privada en la Ciudad de México. Diseño: estudio retrospectivo, observacional, con grupo control y seguimiento longiudinal. Material y métodos: se estudiaron los expedientes clínicos de 150 pacientes intervenidos quirúrgicamente de apendicectomía; todos procedían del servicio de urgencias con diagnóstico de apendicitis aguda y se dividieron en dos grupos: uno de 75 pacientes operados por vía tradicional y otro de 75 sujetos intervenidos por apendicectomía laparoscópica. Se excluyeron del estudio pacientes con operaciones previas en hemiabdomen inferior, con alteraciones que contraindicaban la anestesia general y mujeres embarazadas. Las variables analizadas fueron las siguientes: comienzo del tratamiento por vía oral, analgésico usados, estancia hospitalaria, complicaciones transoperatorias, reintervenciones quirúrgicas, índice de conversión, resultados histopatológicos y días de incapacidad posoperatoria. Resultados: éstos no mostraron diferencias estadísticas significativas en ambos grupos. Con la laparoscopia se obtienen mejores resultados estéticos y la reincorporación a las actividades normales se da en menor tiempo, lo que se traduce en menos días de incapacidad laboral


Assuntos
Humanos , Masculino , Feminino , Apendicectomia , Apendicite/cirurgia , Tempo de Internação , Complicações Intraoperatórias , Reoperação
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