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1.
J Pediatr Adolesc Gynecol ; 37(2): 217-219, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38110028

RESUMO

Ovarian tumors are rare in children; however, their incidence increases with age. Of these ovarian tumors, Leydig cell tumors are some of the rarest, accounting for less than 0.1% of all ovarian tumors across all ages. Leydig cell tumors predominantly occur in postmenopausal women and are characterized by nodular proliferation of Leydig cells in the ovarian hilum with intracytoplasmic Reinke crystals. These tumors secrete androgens, which can disrupt ovarian function, clinically presenting with abnormal uterine bleeding and virilization. Although they are generally benign, current recommendations are for treatment with a unilateral salpingo-oophorectomy. In adolescents, hyperandrogenism is most commonly caused by polycystic ovarian syndrome (PCOS); however, the differential for hyperandrogenism is broad. We present a case of a 15-year-old girl with a history of primary amenorrhea who presented with a Leydig cell tumor associated with recurrent ovarian torsion and virilization. This case reviews the challenges with diagnosis, management, and future implications of a rare androgen-secreting tumor in young patients.


Assuntos
Hiperandrogenismo , Tumor de Células de Leydig , Neoplasias Ovarianas , Masculino , Criança , Humanos , Feminino , Adolescente , Tumor de Células de Leydig/complicações , Tumor de Células de Leydig/cirurgia , Tumor de Células de Leydig/diagnóstico , Hiperandrogenismo/complicações , Virilismo/etiologia , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/cirurgia , Androgênios
2.
J Minim Invasive Gynecol ; 27(1): 166-172, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30930212

RESUMO

STUDY OBJECTIVE: To evaluate the efficacy of nontubal ectopic pregnancy (NTEP) management with direct methotrexate (MTX) injection into the gestational sac. DESIGN: A retrospective chart review. SETTING: A tertiary academic and teaching hospital. PATIENTS: All cases of confirmed NTEP were retrospectively identified from 2012 to 2017. INTERVENTIONS: Ultrasound-guided direct injection of MTX into the fetal pole and surrounding gestational sac and a single dose of systemic MTX with or without fetal intracardiac injection of potassium chloride. MEASUREMENTS AND MAIN RESULTS: Treatment failure, complications from treatment, operating time, and days to negative serum human chorionic gonadotropin (hCG) after treatment were measured. Fourteen women (age 34 ± 5.2 years) with NTEP underwent direct MTX injection (cesarean scar, n = 4; interstitial, n = 6; cervical, n = 4). The mean estimated gestational age was 49 ± 11, CI (43, 56 days). One patient required laparoscopic intervention with a failure rate of 1 of 14 (a double interstitial, heterotopic pregnancy). There were no other major complications. The time in the operating room was similar for all NTEP types. The average time to negative serum hCG was not different for cesarean scar (84.5 ± 36 days), cervical pregnancies (70.5 ± 19 days), or interstitial pregnancies (45.3 ± 38 days, p = .15). CONCLUSION: Direct MTX injection into the gestational sac for NTEP treatment is safe and effective. The failure rate of 7% is considerably lower than what was previously reported for a failure of systemic MTX in similar cases (25%). Resolution of serum hCG after treatment can be quite prolonged even in uncomplicated cases.


Assuntos
Abortivos não Esteroides/administração & dosagem , Saco Gestacional/efeitos dos fármacos , Injeções/métodos , Metotrexato/administração & dosagem , Gravidez Ectópica/tratamento farmacológico , Abortivos não Esteroides/efeitos adversos , Adulto , Feminino , Saco Gestacional/patologia , Humanos , Metotrexato/efeitos adversos , Gravidez , Gravidez Ectópica/patologia , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção , Ultrassonografia Pré-Natal
3.
J Clin Endocrinol Metab ; 99(5): E871-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24650013

RESUMO

CONTEXT: Assisted reproductive technology (ART) cycle cancelation rates are increased among overweight and obese women; however, the reasons for this are not completely clear. Premature luteinization due to inadequate endogenous gonadotropin suppression is a possibility for this higher risk of cancellation. OBJECTIVE: The objective of the study was to investigate the impact of female obesity on the pharmacokinetics of cetrorelix (GnRH antagonist). DESIGN: This was an interventional study. SETTING: The study was conducted at a university clinical and translational research center. PARTICIPANTS: Regularly menstruating obese (n = 10) and normal-weight (n = 10) women participated in the study. INTERVENTIONS: A frequent blood sampling study was performed after a GnRH antagonist was administered, followed by recombinant LH. MAIN OUTCOMES MEASURED: Pharmacokinetics of cetrorelix in obese vs normal weight women were measured. RESULTS: Five of the obese women (50%) and none of the normal-weight women had a rebound of LH (defined as >50% increase in LH level from nadir) over the 14-hour postdose observation period. The obese group had a significantly decreased distributional half-life of cetrorelix compared with the normal-weight group (8.1 ± 1.6 vs 12.7 ± 6.2 hours, P = .02). The obese group exhibited increased clearance of cetrorelix compared with the normal-weight group (25.8 ± 6.8 vs 20.1 ± 8.3 L/h, P = .058). CONCLUSIONS: The altered pharmacokinetics of cetrorelix in obese women may lead to premature ovulation during ART, and this could be one of the mechanisms that results in increased cycle cancelation in this group of women. In accordance with the higher gonadotropin requirements for obese women undergoing ART, weight-based dosing of GnRH antagonists may be required.


Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Antagonistas de Hormônios/farmacocinética , Hipotálamo/efeitos dos fármacos , Obesidade/metabolismo , Adulto , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/sangue , Hormônio Liberador de Gonadotropina/farmacocinética , Antagonistas de Hormônios/sangue , Humanos , Hormônio Luteinizante/sangue , Obesidade/sangue , Indução da Ovulação/métodos
4.
J Assist Reprod Genet ; 31(3): 355-62, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24390626

RESUMO

PURPOSE: To determine if microRNAs are differentially expressed in the follicular fluid of women with PCOS compared to fertile oocyte donors and identify associated altered gene expression. METHODS: Women undergoing IVF who met Rotterdam criteria for PCOS or who were fertile oocyte donors were recruited from a private IVF center. Individual follicle fluid was collected at the time of oocyte retrieval. MicroRNA analysis was performed using microarray and validated using real-time PCR on additional samples. Potential gene targets were identified and their expression analyzed by real time PCR. RESULTS: Microarray profiling of human follicular fluid revealed expression of 235 miRNAs, 29 were differentially expressed between the groups. Using PCR validation, 5 miRNAs (32, 34c, 135a, 18b, and 9) showed significantly increased expression in the PCOS group. Pathway analysis revealed genes involved in insulin regulation and inflammation. Three potential target genes were found to have significantly decreased expression in the PCOS group (interleukin 8, synaptogamin 1, and insulin receptor substrate 2). CONCLUSIONS: MicroRNAs are differentially expressed in the follicular fluid of women with PCOS when compared to fertile oocyte donors. There is also altered expression of potential target genes associated with the PCOS phenotype.


Assuntos
Fertilização in vitro , Regulação da Expressão Gênica/genética , MicroRNAs/biossíntese , Síndrome do Ovário Policístico/genética , Adulto , Feminino , Líquido Folicular/metabolismo , Células da Granulosa/metabolismo , Humanos , MicroRNAs/genética , Oócitos/metabolismo , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia
5.
Semin Reprod Med ; 31(4): 245-50, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23775379

RESUMO

Clomiphene citrate, a selective estrogen receptor modulator, has been used to treat infertility in women and men for 50 years. In men, clomiphene citrate has been employed in the management of unexplained infertility, oligo and asthenospermia, hypogonadism, and nonobstructive azoospermia. The available evidence reveals mixed results and suggests that clomiphene citrate may be appropriate for the management of male infertility in specific clinical scenarios. Further research is needed to clarify when clomiphene citrate is indicated in the treatment of male infertility.


Assuntos
Clomifeno/uso terapêutico , Medicina Baseada em Evidências , Infertilidade Masculina/prevenção & controle , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Astenozoospermia/tratamento farmacológico , Astenozoospermia/fisiopatologia , Azoospermia/tratamento farmacológico , Azoospermia/fisiopatologia , Humanos , Hipogonadismo/tratamento farmacológico , Hipogonadismo/fisiopatologia , Infertilidade Masculina/tratamento farmacológico , Infertilidade Masculina/etiologia , Masculino , Oligospermia/tratamento farmacológico , Oligospermia/fisiopatologia
6.
Obstet Gynecol ; 119(6): 1151-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22617579

RESUMO

OBJECTIVE: Many women with polycystic ovary syndrome (PCOS) experience infertility and hirsutism and often seek treatment for both concurrently. We investigated whether women who ovulate in response to treatment with clomiphene citrate, metformin, or both would have greater improvement in hirsutism compared with those who did not ovulate. METHODS: This is a secondary analysis evaluating the change in Ferriman-Gallwey score for the hirsute women (n=505 [80.7%]) from the Pregnancy in Polycystic Ovary Syndrome I study. This was a prospective, randomized, doubled-blind trial of 626 women with PCOS and infertility recruited from 12 university sites. They were treated with clomiphene citrate, metformin, or both (combination) for up to six cycles, and hirsutism evaluators were blinded to group assignment. RESULTS: There was a significant decrease in the Ferriman-Gallwey score between baseline and completion of the study in each of the three individual groups (clomiphene citrate, P=.024; metformin, P=.005; combination, P<.001). There was no significant difference in the degree to which the hirsutism score changed when comparing the three groups (P=.44). The change in hirsutism was not associated with the duration of treatment or with the presence or absence of ovulation. CONCLUSION: In infertile hirsute women with PCOS, treatment with clomiphene citrate, metformin, or both for up to six cycles does not alter hirsutism. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00068861. LEVEL OF EVIDENCE: II.


Assuntos
Clomifeno/uso terapêutico , Fármacos para a Fertilidade Feminina/uso terapêutico , Hirsutismo/tratamento farmacológico , Metformina/uso terapêutico , Indução da Ovulação/métodos , Síndrome do Ovário Policístico/tratamento farmacológico , Adulto , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Adulto Jovem
7.
J Am Chem Soc ; 134(20): 8416-9, 2012 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-22564208

RESUMO

A detailed study of the eight-electron/eight-proton catalytic reaction of nitrogenase has been hampered by the fact that electron and proton flow in this system is controlled by ATP-dependent protein-protein interactions. Recent studies have shown that it is possible to circumvent the dependence on ATP through the use of potent small-molecule reductants or light-driven electron injection, but success has been limited to two-electron reductions of hydrazine, acetylene, or protons. Here we show that a variant of the molybdenum-iron protein labeled with a Ru-photosensitizer can support the light-driven, six-electron catalytic reduction of hydrogen cyanide into methane and likely also ammonia. Our findings suggest that the efficiency of this light-driven system is limited by the initial one- or two-electron reduction of the catalytic cofactor (FeMoco) to enable substrate binding, but the subsequent electron-transfer steps into the FeMoco-bound substrate proceed efficiently.


Assuntos
Azotobacter vinelandii/enzimologia , Cianeto de Hidrogênio/metabolismo , Metano/metabolismo , Molibdoferredoxina/metabolismo , Amônia/metabolismo , Azotobacter vinelandii/química , Azotobacter vinelandii/genética , Azotobacter vinelandii/metabolismo , Modelos Moleculares , Molibdoferredoxina/química , Molibdoferredoxina/genética , Oxirredução , Mutação Puntual , Conformação Proteica
8.
J Am Chem Soc ; 132(39): 13672-4, 2010 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-20843032

RESUMO

We report here the light-driven activation of the molybdenum-iron-protein (MoFeP) of nitrogenase for substrate reduction independent of ATP hydrolysis and the iron-protein (FeP), which have been believed to be essential for catalytic turnover. A MoFeP variant labeled on its surface with a Ru-photosensitizer is shown to photocatalytically reduce protons and acetylene, most likely at its active site, FeMoco. The uncoupling of nitrogenase catalysis from ATP hydrolysis should enable the study of redox dynamics within MoFeP and the population of discrete reaction intermediates for structural investigations.


Assuntos
Trifosfato de Adenosina/química , Luz , Molibdoferredoxina/química , Nitrogenase/metabolismo , Trifosfato de Adenosina/metabolismo , Biocatálise , Ativação Enzimática , Hidrólise , Modelos Moleculares , Estrutura Molecular , Molibdoferredoxina/metabolismo , Nitrogenase/química , Compostos Organometálicos/química , Fármacos Fotossensibilizantes/química , Ligação Proteica , Rutênio/química , Especificidade por Substrato
9.
Biophys Chem ; 126(1-3): 86-93, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16750290

RESUMO

The structure of a novel acetylcitrulline deacetylase from the plant pathogen Xanthomonas campestris has been solved by multiple-wavelength anomalous dispersion (MAD) using crystals grown from selenomethionine-substituted protein and refined at 1.75 A resolution. The asymmetric unit of the crystal contains one monomer consisting of two domains, a catalytic domain and a dimerization domain. The catalytic domain is able to bind a single Co(II) ion at the active site with no change in conformation. The dimerization domain forms an interface between two monomers related by a crystallographic two-fold symmetry axis. The interface is maintained by hydrophobic interactions between helices and hydrogen bonding between two beta strands that form a continuous beta sheet across the dimer interface. Because the dimers are also related by two-fold crystallographic axes, they pack together across the crystal via the dimerization domain, suggesting that higher order oligomers may form in solution. The polypeptide fold of the monomer is similar to the fold of Pseudomonas sp. carboxypeptidase G2 and Neisseria meningitidis succinyl diaminopimelate desuccinylase. Structural comparison among these enzymes allowed modeling of substrate binding and suggests a possible catalytic mechanism, in which Glu130 functions as a bifunctional general acid-base catalyst and the metal ion polarizes the carbonyl of the acetyl group.


Assuntos
Amidoidrolases/química , Sequência de Aminoácidos , Sítios de Ligação , Domínio Catalítico , Cobalto/química , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Neisseria meningitidis/enzimologia , Conformação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Pseudomonas/enzimologia
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