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1.
Am J Obstet Gynecol ; 230(2): 199-212.e5, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37595823

RESUMEN

OBJECTIVE: This study aimed to investigate whether trophectoderm biopsy for preimplantation genetic testing is associated with an increased risk of adverse obstetrical and neonatal outcomes compared with conventional in vitro fertilization or intracytoplasmic sperm injection without preimplantation genetic testing. DATA SOURCES: Entries between January 1990 and August 2022 were searched using MEDLINE, Embase, Web of Science, the Cochrane Library, and Google Scholar. STUDY ELIGIBILITY CRITERIA: Publications comparing the outcomes of pregnancies after preimplantation genetic testing using trophectoderm biopsy and in vitro fertilization or intracytoplasmic sperm injection were included. Only human studies with a cohort or case-control design or randomized controlled trials were eligible for inclusion. METHODS: The study selection process was performed independently by 2 investigators. The quality of the observational studies was assessed using the Newcastle-Ottawa Scale, and the Cochrane risk-of-bias tool version 2 was used to grade the level of bias in randomized controlled trials. The pooled odds ratio and 95% confidence interval were calculated using a random-effects model when substantial heterogeneity occurred (indicated by I2 of >50% and P<.1). Otherwise, a fixed-effects model was used. RESULTS: This meta-analysis included 13 studies involving 11,469 live births after preimplantation genetic testing treatment with trophectoderm biopsy before embryo transfer and 20,438 live births after in vitro fertilization or intracytoplasmic sperm injection only. The odds ratio of preterm delivery was higher in the trophectoderm-biopsied group than in the routine in vitro fertilization or intracytoplasmic sperm injection group (pooled odds ratio, 1.12; 95% confidence interval, 1.03-1.21); however, the difference did not exist after sensitivity analysis (odds ratio, 0.97; 95% confidence interval, 0.84-1.11). The risk of low birthweight did not increase among the biopsied pregnancies (pooled odds ratio, 1.01; 95% confidence interval, 0.85-1.20). No marked difference was observed in the risk of other obstetrical or neonatal outcomes between the biopsy and control groups. Furthermore, no difference was noted in the perinatal outcomes between trophectoderm-biopsied and nonbiopsied groups in the subgroup analyses by intracytoplasmic sperm injection, frozen-thawed transfer, or single embryo transfer. CONCLUSION: Trophectoderm biopsy for preimplantation genetic testing treatment did not alter the risk of obstetrical or neonatal outcomes compared with conventional in vitro fertilization or intracytoplasmic sperm injection without preimplantation genetic testing. However, this study was limited by the large observational evidence base, and more randomized controlled trials are needed to further confirm these findings.


Asunto(s)
Diagnóstico Preimplantación , Embarazo , Recién Nacido , Femenino , Masculino , Humanos , Semen , Pruebas Genéticas , Fertilización In Vitro/efectos adversos , Biopsia , Estudios Retrospectivos
2.
Brain ; 146(3): 880-897, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36380488

RESUMEN

Distal hereditary motor neuropathies (dHMNs) are a group of inherited diseases involving the progressive, length-dependent axonal degeneration of the lower motor neurons. There are currently 29 reported causative genes and four disease loci implicated in dHMN. Despite the high genetic heterogeneity, mutations in the known genes account for less than 20% of dHMN cases, with the mutations identified predominantly being point mutations or indels. We have expanded the spectrum of dHMN mutations with the identification of a 1.35 Mb complex structural variation (SV) causing a form of autosomal dominant dHMN (DHMN1 OMIM %182906). Given the complex nature of SV mutations and the importance of studying pathogenic mechanisms in a neuronal setting, we generated a patient-derived DHMN1 motor neuron model harbouring the 1.35 Mb complex insertion. The DHMN1 complex insertion creates a duplicated copy of the first 10 exons of the ubiquitin-protein E3 ligase gene (UBE3C) and forms a novel gene-intergenic fusion sense transcript by incorporating a terminal pseudo-exon from intergenic sequence within the DHMN1 locus. The UBE3C intergenic fusion (UBE3C-IF) transcript does not undergo nonsense-mediated decay and results in a significant reduction of wild-type full-length UBE3C (UBE3C-WT) protein levels in DHMN1 iPSC-derived motor neurons. An engineered transgenic Caenorhabditis elegans model expressing the UBE3C-IF transcript in GABA-ergic motor neurons shows neuronal synaptic transmission deficits. Furthermore, the transgenic animals are susceptible to heat stress, which may implicate defective protein homeostasis underlying DHMN1 pathogenesis. Identification of the novel UBE3C-IF gene-intergenic fusion transcript in motor neurons highlights a potential new disease mechanism underlying axonal and motor neuron degeneration. These complementary models serve as a powerful paradigm for studying the DHMN1 complex SV and an invaluable tool for defining therapeutic targets for DHMN1.


Asunto(s)
Atrofia Muscular Espinal , Ubiquitina-Proteína Ligasas , Animales , Atrofia Muscular Espinal/genética , Mutación , Ubiquitina/genética , Ubiquitina-Proteína Ligasas/genética , Humanos
3.
J Assist Reprod Genet ; 41(3): 683-691, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38403803

RESUMEN

PURPOSE: This study aimed to investigate the association between mild elevation of thyroid-stimulating hormone (TSH) levels and pregnancy outcomes of in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatments in women with the first fresh embryo transfer. METHODS: Large single-center retrospective cohort study of 15,728 patients from January 2018 to December 2022 were enrolled in the analyses. Clinical pregnancy rates, live birth rates, miscarriage rates, and ectopic pregnancy rates were compared between the TSH levels < 2.5 mIU/L group (N = 10,932) and TSH levels ≥ 2.5 mIU/L group (N = 4796). Subgroup analysis was performed for patients with TSH levels ≥ 2.5 mIU/L, dividing them into the thyroid peroxidase antibody (TPO)-negative group (N = 4524) and the TPO-positive group (N = 272). RESULTS: There were no significant differences in the aforementioned pregnancy outcomes between the TSH levels < 2.5 mIU/L group and TSH levels ≥ 2.5 mIU/L group. Similarly, no significant differences were observed in the pregnancy outcomes between the TPO-negative group and the TPO-positive group. CONCLUSION: Mildly elevated pre-conception TSH levels in thyroid-normal infertile patients did not have an impact on pregnancy outcomes of IVF/ICSI treatments.


Asunto(s)
Inyecciones de Esperma Intracitoplasmáticas , Tirotropina , Masculino , Embarazo , Humanos , Femenino , Estudios Retrospectivos , Semen , Fertilización In Vitro , Transferencia de Embrión , Índice de Embarazo
4.
J Biol Chem ; 295(36): 12573-12587, 2020 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-32605924

RESUMEN

The herb dwarf lilyturf tuber (Maidong, Ophiopogonis Radix) is widely used in Chinese traditional medicine to manage diabetes and its complications. However, the role of Maidong polysaccharide extract (MPE) in pancreatic ß-cell function is unclear. Here, we investigated whether MPE protects ß-cell function and studied the underlying mechanisms. We treated db/db and high-fat diet (HFD)-induced obese mice with 800 or 400 mg/kg MPE or water for 4 weeks, followed by an oral glucose tolerance test. Pancreas and blood were collected for molecular analyses, and clonal MIN6 ß-cells and primary islets from HFD-induced obese mice and normal chow diet-fed mice were used in additional analyses. In vivo, MPE both increased insulin secretion and reduced blood glucose in the db/db mice but increased only insulin secretion in the HFD-induced obese mice. MPE substantially increased the ß-cell area in both models (3-fold and 2-fold, p < 0.01, for db/db and HFD mice, respectively). We observed reduced nuclear translocation of the p65 subunit of NF-κB in islets of MPE-treated db/db mice, coinciding with enhanced glucose-stimulated insulin secretion (GSIS). In vitro, MPE potentiated GSIS and decreased interleukin 1ß (IL-1ß) secretion in MIN6 ß-cells. Incubation of MIN6 cells with tumor necrosis factor α (TNFα), interferon-γ, and IL-1ß amplified IL-1ß secretion and inhibited GSIS. These effects were partially reversed with MPE or the IκB kinase ß inhibitor PS1145, coinciding with reduced activation of p65 and p-IκB in the NF-κB pathway. We conclude that MPE may have potential for therapeutic development for ß-cell protection.


Asunto(s)
Quinasa I-kappa B/metabolismo , Secreción de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Interleucina-1beta/metabolismo , Obesidad/metabolismo , Ophiopogon/química , Extractos Vegetales , Tubérculos de la Planta/genética , Factor de Transcripción ReIA/metabolismo , Animales , Línea Celular , Grasas de la Dieta/efectos adversos , Grasas de la Dieta/farmacología , Inflamación/metabolismo , Inflamación/patología , Células Secretoras de Insulina/patología , Ratones , Obesidad/inducido químicamente , Obesidad/tratamiento farmacológico , Obesidad/patología , Extractos Vegetales/química , Extractos Vegetales/farmacología
5.
J Am Chem Soc ; 142(3): 1142-1146, 2020 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-31899620

RESUMEN

We accidentally found that YM-53601, a known small-molecule inhibitor of squalene synthase (SQS), selectively depletes SQS from mammalian cells upon UV irradiation. Further analyses indicated that the photodepletion of SQS requires its short peptide segment located at the COOH terminus. Remarkably, when the 27 amino acid peptide was fused to green fluorescent protein or unrelated proteins at either the NH2 or COOH terminus, such fusion proteins were selectively depleted when the cells were treated with both YM-53601 and UV exposure. Product analysis and electron spin resonance experiments suggested that the UV irradiation promotes homolytic C-O bond cleavage of the aryl ether group in YM-53601. It is likely that the radical species generated from UV-activated YM-53601 abstract hydrogen atoms from the SQS peptide, leading to the photolysis of the entire protein. The pair of the SQS peptide and YM-53601 discovered in the present study paves the way for the design of a new small-molecule-controlled optogenetic tool.


Asunto(s)
Farnesil Difosfato Farnesil Transferasa/antagonistas & inhibidores , Péptidos/farmacología , Fotólisis , Quinuclidinas/farmacología , Células HEK293 , Humanos
6.
Zhongguo Zhong Yao Za Zhi ; 44(14): 2947-2952, 2019 Jul.
Artículo en Zh | MEDLINE | ID: mdl-31602838

RESUMEN

The aim of this paper was to discuss the protective effect and mechanism of Acanthopanax senticosus polysaccharides( ASPs) on immunological liver injury caused by conanavalin A( Con A). BALB/c mice were randomly divided into seven groups: control group,model group( Con A),low-,medium-,and high-dose( 36. 25,72. 5,145 mg·kg~(-1)) ASPs groups,bifendate( 200 mg·kg~(-1),positive drug) group and pyrrolidinedithiocarbamate( PDTC,NF-κB inhibitor,200 mg·kg~(-1)) group. ASPs groups and bifendate group were given with corresponding drugs by ig administration once daily for 7 d. Control group,model group and PDTC group were given with normal saline by ig administration once daily for 7 d. After the last ig administration,PDTC was given in DTC group by iv administration( 200 mg·kg~(-1)); 0. 5 h after that,Con A( 20 mg·kg~(-1)) was injected via the tail vein to induce immunological liver injury in all the mice except normal control group. The mice were killed 8 h later and their liver tissues were collected for histopathological examination. The contents of nitric oxide( NO),superoxide dismutase( SOD),malondialdehyde( MDA),reduced glutathione( GSHPX),interleukin( IL-1ß) and tumor necrosis factor( TNF-α) in liver tissues were detected by kit assay. Western blot method was used to detect TNF-α,intercellular cell adhesion molecule-1( ICAM-1),inducible nitric oxide synthase( i NOS) and nuclear factor( NF-κB) protein expression in liver tissues. As compared with model group,ASPs not only could reduce the activity of MDA,NO,IL-1ß and TNF-α,but also increase the content of GSH-PX and SOD; at the same time,the protein expression levels of TNF-α,ICAM-1,i NOS and NF-κB were reduced in liver tissues; in addition,inflammatory cell infiltration was alleviated,hepatocyte cytoplasm was loose and swollen,and nuclear condensation and staining were improved. ASPs has a protective effect on immunological liver injury,and the mechanism may be associated with regulating secretion of inflammatory cytokines and the expression of adhesion factor through NF-κB signaling pathway.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Citocinas/metabolismo , Eleutherococcus/química , Polisacáridos/farmacología , Animales , Conotoxinas , Hígado/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , FN-kappa B/metabolismo , Péptidos Cíclicos , Distribución Aleatoria , Transducción de Señal
7.
Angew Chem Int Ed Engl ; 56(7): 1765-1770, 2017 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-28067441

RESUMEN

A major hurdle in stem cell therapy is the tumorigenic risk of residual undifferentiated stem cells. This report describes the design and evaluation of synthetic hybrid molecules that efficiently reduce the number of human induced pluripotent stem cells (hiPSCs) in cell mixtures. The design takes advantage of Kyoto probe 1 (KP-1), a fluorescent chemical probe for hiPSCs, and clinically used anticancer drugs. Among the KP-1-drug conjugates we synthesized, we found an exceptionally selective, chemically tractable molecule that induced the death of hiPSCs. Mechanistic analysis suggested that the high selectivity originates from the synergistic combination of transporter-mediated efflux and the cytotoxicity mode of action. The present study offers a chemical and mechanistic rationale for designing selective, safe, and simple reagents for the preparation of non-tumorigenic clinical samples.


Asunto(s)
Antineoplásicos/química , Separación Celular/métodos , Colorantes Fluorescentes/química , Células Madre Pluripotentes Inducidas/citología , Rodaminas/química , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Antineoplásicos/farmacología , Muerte Celular/efectos de los fármacos , Línea Celular , Colorantes Fluorescentes/farmacología , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/metabolismo , Rodaminas/farmacología
8.
Nat Chem Biol ; 10(2): 141-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24316738

RESUMEN

Cell replacement therapy for diabetes mellitus requires cost-effective generation of high-quality, insulin-producing, pancreatic ß cells from pluripotent stem cells. Development of this technique has been hampered by a lack of knowledge of the molecular mechanisms underlying ß-cell differentiation. The present study identified reserpine and tetrabenazine (TBZ), both vesicular monoamine transporter 2 (VMAT2) inhibitors, as promoters of late-stage differentiation of Pdx1-positive pancreatic progenitor cells into Neurog3 (referred to henceforth as Ngn3)-positive endocrine precursors. VMAT2-controlled monoamines, such as dopamine, histamine and serotonin, negatively regulated ß-cell differentiation. Reserpine or TBZ acted additively with dibutyryl adenosine 3',5'-cyclic AMP, a cell-permeable cAMP analog, to potentiate differentiation of embryonic stem (ES) cells into ß cells that exhibited glucose-stimulated insulin secretion. When ES cell-derived ß cells were transplanted into AKITA diabetic mice, the cells reversed hyperglycemia. Our protocol provides a basis for the understanding of ß-cell differentiation and its application to a cost-effective production of functional ß cells for cell therapy.


Asunto(s)
Diferenciación Celular , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/metabolismo , Proteínas de Transporte Vesicular de Monoaminas/metabolismo , Inhibidores de Captación Adrenérgica/farmacología , Animales , Diabetes Mellitus Experimental , Células Madre Embrionarias/efectos de los fármacos , Humanos , Hiperglucemia/terapia , Ratones , Estructura Molecular , Reserpina/química , Reserpina/farmacología , Tetrabenazina/química , Tetrabenazina/farmacología , Proteínas de Transporte Vesicular de Monoaminas/antagonistas & inhibidores , Proteínas de Transporte Vesicular de Monoaminas/genética
9.
J Am Chem Soc ; 136(28): 9798-801, 2014 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-24992689

RESUMEN

One of the current obstacles to stem cell therapy is the tumorigenic potential of residual undifferentiated stem cells. The present study reports rediscovery of a synthetic derivative of okadaic acid, a marine polyether toxin, as a reagent that selectively induces the death of human pluripotent stem cells. Cell-based screening of 333 cytotoxic compounds identified methyl 27-deoxy-27-oxookadaate (molecule 1) as a substrate of two ATP-binding cassette (ABC) transporters, ABCB1 (MDR1) and ABCG2 (BCRP), whose expression is repressed in human embryonic stem cells and induced pluripotent stem cells. The results demonstrate that selective elimination of human pluripotent stem cells can be achieved by designing cytotoxic small molecules with appropriate ABC-transporter selectivity.


Asunto(s)
Productos Biológicos/farmacología , Ácido Ocadaico/análogos & derivados , Ácido Ocadaico/farmacología , Células Madre Pluripotentes/efectos de los fármacos , Rodaminas/química , Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Colorantes Fluorescentes , Humanos , Neuronas/efectos de los fármacos
10.
Hum Reprod Open ; 2024(2): hoae024, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38764909

RESUMEN

STUDY QUESTION: Is SARS-CoV-2 infection in IVF-conceived early pregnancy associated with a higher risk of miscarriage? SUMMARY ANSWER: Infection with SARS-CoV-2 during early pregnancy in women conceiving by IVF may not be associated with an increased rate of miscarriage. WHAT IS KNOWN ALREADY: In naturally conceived pregnancies, most findings have shown that SARS-CoV-2 infection does not increase the risk of miscarriage, while some studies have shown that SARS-CoV-2 infection is associated with a higher risk of miscarriage. STUDY DESIGN SIZE DURATION: A matched retrospective cohort study was conducted in a tertiary hospital-based reproductive medicine center. The infection group included women who contracted coronavirus disease 2019 (COVID-19) before 20 weeks gestation from 6 December 2022 to 10 January 2023. Each infected woman was matched with three historical control subjects from 1 January 2018 to 31 May 2022. PARTICIPANTS/MATERIALS SETTING METHODS: The infection group was matched with historical control subjects based on female age (±1 year), number of gestational sacs, number of previous miscarriages, BMI (±2 kg/cm2), main causes of infertility, gestational week, and fresh versus frozen embryo transfer. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 150 pregnant women infected with COVID-19 before 20 weeks of gestation were included in the infection group, which was matched at a 3:1 ratio with 450 historically pregnant controls. There were no significant differences in age, BMI, and endometrial thickness between the two groups. The overall incidence of miscarriage was not significantly different between the infection group and the control group (4.7% versus 5.8%, P = 0.68). When the infection group was stratified into three subgroups based on the gestational age at the onset of infection (0-7 + 6, 8-11 + 6, and 12-19 + 6 weeks), no significant differences were observed in the incidence of miscarriage between the infection group and the matched control group in any of the subgroups (9.8% versus 13.8%, P = 0.60; 5.4% versus 4.5%, P = 1.00; and 1.4% versus 1.9%, P = 1.00, respectively). LIMITATIONS REASONS FOR CAUTION: The major limitation of this study is the relatively small sample size; therefore, caution is suggested when drawing any definitive conclusions. Nonetheless, our study is the largest sample study of the influence of COVID-19 infection on the miscarriage rate in early pregnancy after IVF. WIDER IMPLICATIONS OF THE FINDINGS: Our findings may provide important insights for reproductive physicians and obstetricians during preconception and early pregnancy counseling. STUDY FUNDING/COMPETING INTERESTS: This study was supported by the Natural Science Foundation of Guangdong Province (No. 2023A1515010250). The authors report no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

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