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1.
Reprod Sci ; 30(10): 3071-3076, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37171775

RESUMO

To compare the rate of positive thyroid peroxidase antibodies (TPO Ab) between women with different polycystic ovary syndrome (PCOS) phenotypes and women without PCOS. This is a retrospective cohort study. Women with PCOS at My Duc Hospital between June 1, 2020, and March 27, 2021, were matched with non-PCOS women by age. TPO Ab (cut-off: 34 IU/mL) and thyroid-stimulating hormone (TSH) levels were measured as markers of Hashimoto thyroiditis and thyroid function, respectively. One thousand eight hundred eight infertile women were included, 904 with PCOS (mean age 29.0 ± 3.58 years) and 904 without PCOS (29.1 ± 3.4 years; controls). Women with PCOS had a higher body mass index (22.8 ± 3.84 vs. 19.9 ± 2.23 kg/m2, p < 0.001), but most were not overweight/obese. Rates of positive TPO Ab in women with versus without PCOS were 8.2% and 8.4%, respectively (p = 0.932). Rates of positive TPO Ab in patients with PCOS phenotype A, B, C, or D were not statistically different (7.5%, 2.9%, 20.0%, and 7.8%, respectively). Median TSH concentrations were similar in the PCOS and control groups (1.84 mIU/L vs. 1.78 mIU/L, respectively; p = 0.194). Based on a linear regression model, there was no correlation between either BMI or the estradiol to progesterone ratio and TPO Ab status. In a large population of infertile women with PCOS who were mostly lean patients, rates of positive TPO Ab across all four PCOS phenotypes did not differ significantly from those in women without PCOS. These findings did not support the hypothesis that PCOS is a risk factor for Hashimoto thyroiditis.


Assuntos
Doença de Hashimoto , Infertilidade Feminina , Síndrome do Ovário Policístico , Humanos , Feminino , Adulto , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/epidemiologia , Estudos Retrospectivos , Tireotropina , Iodeto Peroxidase
2.
Acta Obstet Gynecol Scand ; 102(5): 626-634, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36905390

RESUMO

INTRODUCTION: Preterm birth is the most common cause of neonatal morbidity and mortality. Women with twin pregnancies and a short cervical length are at high risk for preterm birth. Vaginal progesterone and cervical pessary have been proposed as potential strategies to reduce preterm birth in this high-risk population. Therefore, we aimed to compare the effectiveness of cervical pessary and vaginal progesterone in improving developmental outcomes of children born to women with twin pregnancies and mid-trimester short cervical length. MATERIAL AND METHODS: This was a follow-up study (NCT04295187) of all children at 24 months of age, born from women treated with cervical pessary or progesterone to prevent preterm birth in a randomized controlled trial (NCT02623881). We used a validated Vietnamese version of Ages & Stages Third Edition Questionnaires (ASQ-3) and a red flag questionnaire. In surviving children, we compared the mean ASQ-3 scores, abnormal ASQ-3 scores, the number of children with any abnormal ASQ-3 scores and red flag signs between the two groups. We reported the composite outcome of perinatal death or survival with any abnormal ASQ-3 score in offspring. These outcomes were also calculated in a subgroup of women with a cervical length ≤28 mm (<25th percentile). RESULTS: In the original randomized controlled trial, we randomized 300 women to pessary or progesterone. After counting the number of perinatal deaths and lost to follow-up, 82.8% parents in the pessary group and 82.5% parents in progesterone group returned the questionnaire. The mean ASQ-3 scores of the five skills and red flag signs did not differ significantly between the two groups. However, the percentage of children having abnormal ASQ-3 scores in fine motor skills was significantly lower in the progesterone group (6.1% vs 1.3%, P = 0.01). There were no significant differences in the composite outcome of perinatal death or survival with any abnormal ASQ-3 score in unselected women and in those with cervical length ≤28 mm. CONCLUSIONS: Cervical pessary and vaginal progesterone may have comparable effects on developmental outcomes in children at ≥24 months of age, born to women with twin pregnancies and short cervical length. However, this finding could be likely due to a lack of study power.


Assuntos
Morte Perinatal , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Criança , Humanos , Progesterona , Gravidez de Gêmeos , Seguimentos , Nascimento Prematuro/prevenção & controle , Pessários , Colo do Útero , Administração Intravaginal
3.
Angew Chem Int Ed Engl ; 62(9): e202211794, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36524997

RESUMO

A flurry of recent research has centered on harnessing the power of nickel catalysis in organic synthesis. These efforts have been bolstered by contemporaneous development of well-defined nickel (pre)catalysts with diverse structure and reactivity. In this report, we present ten different bench-stable, 18-electron, formally zero-valent nickel-olefin complexes that are competent pre-catalysts in various reactions. Our investigation includes preparations of novel, bench-stable Ni(COD)(L) complexes (COD=1,5-cyclooctadiene), in which L=quinone, cyclopentadienone, thiophene-S-oxide, and fulvene. Characterization by NMR, IR, single-crystal X-ray diffraction, cyclic voltammetry, thermogravimetric analysis, and natural bond orbital analysis sheds light on the structure, bonding, and properties of these complexes. Applications in an assortment of nickel-catalyzed reactions underscore the complementary nature of the different pre-catalysts within this toolkit.

4.
ACS Chem Biol ; 17(5): 1249-1258, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35417146

RESUMO

Recent clinical trials have revealed that the chimeric peptide hormones simultaneously activating glucagon-like peptide-1 receptor (GLP-1R) and glucose-dependent insulinotropic polypeptide receptor (GIPR) demonstrate superior efficacy in glycemic control and body weight reduction, better than those activating the GLP-1R alone. However, the linear peptide-based GLP-1R/GIPR dual agonists are susceptible to proteolytic cleavage by common digestive enzymes present in the gastrointestinal tract and thus not suitable for oral administration. Here, we report the design and synthesis of biaryl-stapled peptides, with and without fatty diacid attachment, that showed potent GLP-1R/GIPR dual agonist activities. Compared to a linear peptide dual agonist and semaglutide, the biaryl-stapled peptides displayed drastically improved proteolytic stability against the common digestive enzymes. Furthermore, two stapled peptides showed excellent efficacy in an oral glucose tolerance test in mice, owing to their potent receptor activity in vitro and good pharmacokinetics exposure upon subcutaneous injection. By exploring a more comprehensive set of biaryl staplers, we expect that this stapling method could facilitate the design of the stapled peptide-based dual agonists suitable for oral administration.


Assuntos
Receptores dos Hormônios Gastrointestinais , Animais , Polipeptídeo Inibidor Gástrico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Camundongos , Peptídeos/farmacologia , Receptores Acoplados a Proteínas G , Receptores dos Hormônios Gastrointestinais/agonistas
5.
Angew Chem Int Ed Engl ; 59(51): 23306-23312, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-32894810

RESUMO

A nickel-catalyzed regiodivergent hydroarylation and hydroalkenylation of unactivated alkenyl carboxylic acids is reported, whereby the ligand environment around the metal center dictates the regiochemical outcome. Markovnikov hydrofunctionalization products are obtained under mild ligand-free conditions, with up to 99 % yield and >20:1 selectivity. Alternatively, anti-Markovnikov products can be accessed with a novel 4,4-disubstituted Pyrox ligand in excellent yield and >20:1 selectivity. Both electronic and steric effects on the ligand contribute to the high yield and selectivity. Mechanistic studies suggest a change in the turnover-limiting and selectivity-determining step induced by the optimal ligand. DFT calculations reveal that in the anti-Markovnikov pathway, repulsion between the ligand and the alkyl group is minimized (by virtue of it being 1° versus 2°) in the rate- and regioselectivity-determining transmetalation transition state.


Assuntos
Alcenos/química , Ácidos Carboxílicos/química , Hidrocarbonetos/síntese química , Níquel/química , Catálise , Teoria da Densidade Funcional , Hidrocarbonetos/química , Ligantes , Estrutura Molecular , Estereoisomerismo
6.
Molecules ; 25(11)2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32481528

RESUMO

Owing to their pleiotropic metabolic benefits, glucagon-like peptide-1 receptor (GLP-1R) agonists have been successfully utilized for treating metabolic diseases, such as type 2 diabetes and obesity. As part of our efforts in developing long-acting peptide therapeutics, we have previously reported a peptide engineering strategy that combines peptide side chain stapling with covalent integration of a serum protein-binding motif in a single step. Herein, we have used this strategy to develop a second generation extendin-4 analog rigidified with a symmetrical staple, which exhibits an excellent in vivo efficacy in an animal model of diabetes and obesity. To simplify the scale-up manufacturing of the lead GLP-1R agonist, a semisynthesis protocol was successfully developed, which involves recombinant expression of the linear peptide followed by attachment of a polyethylene glycol (PEG)-fatty acid staple in a subsequent chemical reaction step.


Assuntos
Exenatida/análogos & derivados , Exenatida/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Animais , Diabetes Mellitus Tipo 2 , Exenatida/química , Ácidos Graxos/química , Masculino , Camundongos , Estrutura Molecular , Obesidade , Peptídeos/química , Peptídeos/metabolismo , Polietilenoglicóis/química
7.
Sci Adv ; 6(20): eaaz4988, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32440547

RESUMO

Existing long α-helix mimicking necessitates the retention of most natural amino acid residues to maintain their biological activity. Here, we report the exploration of helical sulfono-γ-AApeptides with entire unnatural backbones for their ability to structurally and functionally mimic glucagon-like peptide 1 (GLP-1). Our findings suggest that efficient construction of novel GLP-1 receptor (GLP-1R) agonists could be achieved with nanomolar potencies. In addition, the resulting sulfono-γ-AApeptides were also proved to display remarkable stability against enzymatic degradation compared to GLP-1, augmenting their biological potential. This alternative strategy of α-helix mimicking, as a proof of concept, could provide a new paradigm to prepare GLP-1R agonists.


Assuntos
Peptídeo 1 Semelhante ao Glucagon , Peptidomiméticos , Peptídeos/química , Peptidomiméticos/química , Conformação Proteica em alfa-Hélice
8.
Angew Chem Int Ed Engl ; 59(19): 7409-7413, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32065839

RESUMO

We report that Ni(COD)(DQ) (COD=1,5-cyclooctadiene, DQ=duroquinone), an air-stable 18-electron complex originally described by Schrauzer in 1962, is a competent precatalyst for a variety of nickel-catalyzed synthetic methods from the literature. Due to its apparent stability, use of Ni(COD)(DQ) as a precatalyst allows reactions to be conveniently performed without use of an inert-atmosphere glovebox, as demonstrated across several case studies.

9.
Angew Chem Int Ed Engl ; 59(18): 7029-7034, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-31958202

RESUMO

Allylation and conjunctive cross-coupling represent two useful, yet largely distinct, reactivity paradigms in catalysis. The union of these two processes would offer exciting possibilities in organic synthesis but remains largely unknown. Herein, we report the use of allyl electrophiles in nickel-catalyzed conjunctive cross-coupling with a non-conjugated alkene and dimethylzinc. The transformation is enabled by weakly coordinating, monodentate aza-heterocycle directing groups that are useful building blocks in synthesis, including saccharin, pyridones, pyrazoles, and triazoles. The reaction occurs under mild conditions and is compatible with a wide range of allyl electrophiles. High chemoselectivity through substrate directivity is demonstrated by the facile reactivity of the ß-γ alkene of the starting material, whereas the ϵ-ζ alkene of the product is preserved. The generality of this approach is further illustrated through the development of an analogous method with alkyne substrates. Mechanistic studies reveal the importance of the dissociation of the weakly coordinating directing group to allow the allyl moiety to bind and facilitate C(sp3 )-C(sp3 ) reductive elimination.


Assuntos
Compostos Alílicos/química , Níquel/química , Pirazóis/síntese química , Piridonas/síntese química , Sacarina/síntese química , Triazóis/síntese química , Alcenos/química , Alquilação , Catálise , Estrutura Molecular , Compostos Organometálicos/química , Pirazóis/química , Piridonas/química , Sacarina/química , Estereoisomerismo , Triazóis/química
10.
Chem Sci ; 11(17): 4287-4296, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-34122886

RESUMO

Nickel-catalyzed three-component alkene difunctionalization has rapidly emerged as a powerful tool for forging two C-C bonds in a single reaction. Building upon the powerful modes of bond construction in traditional two-component cross-coupling, various research groups have demonstrated the versatility of nickel in enabling catalytic 1,2-dicarbofunctionalization using a wide range of carbon-based electrophiles and nucleophiles and in a fully intermolecular fashion. Though this area has emerged only recently, the last few years have witnessed a proliferation of publications on this topic, underscoring the potential of this strategy to develop into a general platform that offers high regio- and stereoselectivity. This minireview highlights the recent progress in the area of intermolecular 1,2-dicarbofunctionalization of alkenes via nickel catalysis and discusses lingering challenges within this reactivity paradigm.

11.
Angew Chem Int Ed Engl ; 59(3): 1201-1205, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-31693286

RESUMO

A nickel-catalyzed conjunctive cross-coupling of alkenyl carboxylic acids, aryl iodides, and aryl/alkenyl boronic esters is reported. The reaction delivers the desired 1,2-diarylated and 1,2-arylalkenylated products with excellent regiocontrol. To demonstrate the synthetic utility of the method, a representative product is prepared on gram scale and then diversified to eight 1,2,3-trifunctionalized building blocks using two-electron and one-electron logic. Using this method, three routes toward bioactive molecules are improved in terms of yield and/or step count. This method represents the first example of catalytic 1,2-diarylation of an alkene directed by a native carboxylate group.

12.
J Am Chem Soc ; 140(51): 17878-17883, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30525575

RESUMO

A nickel-catalyzed conjunctive cross-coupling of simple alkenyl amides with aryl iodides and aryl boronic esters is reported. The reaction is enabled by an electron-deficient olefin (EDO) ligand, dimethyl fumarate, and delivers the desired 1,2-diarylated products with excellent regiocontrol. Under optimized conditions, a wide range of amides derived from 3-butenoic acid, 4-pentenoic acid, and allyl amine are compatible substrates. This method represents the first example of regiocontrolled 1,2-diarylation directed by a native amide functional group. Computational analysis sheds light on the potential substrate binding mode and the role of the EDO ligand in the reductive elimination step.


Assuntos
Alcenos/síntese química , Amidas/síntese química , Ácidos Borônicos/química , Complexos de Coordenação/química , Iodobenzenos/química , Níquel/química , Catálise , Fumarato de Dimetilo/química , Ligantes , Modelos Químicos
13.
Chem Sci ; 9(23): 5278-5283, 2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-29997883

RESUMO

A nickel-catalyzed conjunctive cross-coupling of non-conjugated alkenes, alkyl halides, and alkylzinc reagents is reported. Regioselectivity is controlled by chelation of a removable bidentate 8-aminoquinoline directing group. Under optimized conditions, a wide range of 1,2-dialkylated products can be accessed in moderate to excellent yields. To the best of our knowledge, this report represents the first example of three-component 1,2-dialkylation of non-conjugated alkenes to introduce differentiated alkyl fragments.

14.
J Am Chem Soc ; 139(31): 10657-10660, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28738150

RESUMO

A nickel-catalyzed conjunctive cross-coupling between non-conjugated alkenes, aryl iodides, and alkylzinc reagents is reported. Excellent regiocontrol is achieved utilizing an 8-aminoquinoline directing group that can be readily cleaved to unmask net ß,γ-dicarbofunctionalized carboxylic acid products. Under optimized conditions, both terminal and internal alkene substrates provided the corresponding alkyl/aryl difunctionalized products in moderate to excellent yields. The methodology developed herein represents the first three-component 1,2-dicarbofunctionalization of non-conjugated alkenes involving a C(sp3)-C(sp3) reductive elimination step.

15.
J Thorac Cardiovasc Surg ; 129(5): 1050-5, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15867779

RESUMO

OBJECTIVE: The study's objective was to comparatively evaluate surgery and stent-graft repair of acute or subacute traumatic aortic rupture. METHODS: A total of 76 patients (14-76 years old; mean, 37 years; male/female ratio, 63/11) with a traumatic aortic injury were admitted to our hospital between 1981 and 2003. Six patients died within 1 to 9 days of another associated severe traumatic lesion. The 70 remaining patients were divided according to the type of rupture repair. In group 1, 35 patients were treated surgically: 28 with immediate repair and 7 with delayed repair (average time interval 66 days, 5-257 days). In group 2, 29 patients were treated with stent grafting of the aortic isthmus. In group 3, 6 patients with minor aortic lesions were treated medically with a close follow-up. RESULTS: In the 28 patients treated surgically in the emergency department, the mortality and paraplegia rates were 21% and 7%, respectively. No death or paraplegia was observed in the group with delayed surgical repair. With stent grafting, complete exclusion of the pseudoaneurysmal sac was observed in all patients. Except for 1 iliac rupture treated during the same procedure, there was no major morbidity or mortality during the mean follow-up of 46 months (13-90 months). No major complication was observed in group 3. CONCLUSIONS: In stable rupture of the aorta, initial conservative treatment is safe and allows management of the major associated lesions. Stent grafting of the aortic isthmus is a valuable therapeutic alternative to surgical repair, especially in patients considered high risk for conventional thoracotomy.


Assuntos
Angioplastia com Balão/métodos , Aorta Torácica/lesões , Ruptura Aórtica/terapia , Implante de Prótese Vascular/métodos , Stents , Ferimentos não Penetrantes/complicações , Acidentes de Trânsito , Doença Aguda , Análise de Variância , Angiografia Digital , Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/instrumentação , Angioplastia com Balão/mortalidade , Ruptura Aórtica/diagnóstico , Ruptura Aórtica/etiologia , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Ecocardiografia Transesofagiana , Feminino , Seguimentos , Humanos , Escala de Gravidade do Ferimento , Masculino , Seleção de Pacientes , Estudos Retrospectivos , Stents/efeitos adversos , Toracotomia/efeitos adversos , Toracotomia/instrumentação , Toracotomia/métodos , Toracotomia/mortalidade , Fatores de Tempo , Tomografia Computadorizada Espiral , Resultado do Tratamento
16.
Clin Nephrol ; 63(5): 405-7, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15909603

RESUMO

We report on the first case of acute renal failure related to obstructive urinary tract lithiasis involving sulfadiazine crystals in a kidney transplant recipient. This patient had disseminated toxoplasmosis which was treated by sulfadiazine (4 g/day) and pyrimethamine (50 mg/day). In the fourth week of anti-toxoplasmosis therapy, he presented with obstructive acute renal failure: the plasma creatinine level increased from 220 micromol/l to 547 micromol/l. Apercutaneous pyelography was conducted showing the presence of a lithiasis located at the junction between the graft ureter and the bladder. Six days later, he underwent surgery to retrieve an orange-colored, friable stone. Its spectrophotometric analysis confirmed that the stone consisted of N-acetyl sulfadiazine crystals.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Sulfadiazina/efeitos adversos , Cálculos Urinários/induzido quimicamente , Cálculos Urinários/terapia , Injúria Renal Aguda/fisiopatologia , Adulto , Drenagem/métodos , Seguimentos , Fungemia/diagnóstico , Fungemia/tratamento farmacológico , Humanos , Testes de Função Renal , Transplante de Rim , Litotripsia/métodos , Masculino , Medição de Risco , Índice de Gravidade de Doença , Sulfadiazina/uso terapêutico , Toxoplasmose/diagnóstico , Toxoplasmose/tratamento farmacológico , Resultado do Tratamento , Cálculos Ureterais/induzido quimicamente , Cálculos Ureterais/patologia , Cálculos Ureterais/terapia , Cálculos da Bexiga Urinária/induzido quimicamente , Cálculos da Bexiga Urinária/patologia , Cálculos da Bexiga Urinária/terapia , Cálculos Urinários/patologia
18.
Arch Mal Coeur Vaiss ; 79(6): 888-91, 1986 Jun.
Artigo em Francês | MEDLINE | ID: mdl-3099706

RESUMO

Use of converting-enzyme inhibitors in patients with hypertension and bilateral renal artery stenosis or renal artery stenosis in a single kidney may be complicated by acute renal failure (ARF). The aim of this work was to find a simple test to predict this accident. PAH clearance (CPAH), Inuline clearance (CIn) and Glomerular Filtration Fraction (GFF) were measured before and three hours after a single oral dose of Captopril (50 mg) in 7 hypertensive patients (sodium intake = 6 g/24 h). All these patients presented significant stenosis (greater than 60%) of the artery of a transplanted kidney (5), of a single kidney (1) or a bilateral renal artery stenosis (1). During the following three days, 50 mg captopril was given twice a day. ARF with creatinine serum level higher than 300 mumoles/l was seen in 4 patients (Group II); in 3 patients (Group I) creatinine serum level didn't change. Values measured before the single dose of captopril and variations after three hours are reported in the table: (Table: see text). Before captopril, in Group II CPAH and CIn are lower and GFF is higher, but these is not significant difference between the two groups. After Captopril CIn and GFF are significantly decreased in Group II (29.1 and 36.6% vs 7.8 and 10%). These results allow two conclusions: 1) Basal values of Glomerular Filtration Rate plasma flow and filtration fraction are not predictive parameters for acute renal failure after captopril therapy.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Injúria Renal Aguda/induzido quimicamente , Captopril/efeitos adversos , Hipertensão Renovascular/tratamento farmacológico , Creatinina/sangue , Humanos , Hipertensão Renovascular/patologia , Hipertensão Renovascular/fisiopatologia , Rim/fisiopatologia , Artéria Renal/patologia , Sistema Renina-Angiotensina
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