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1.
Cell ; 150(4): 673-84, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22901802

RESUMO

A pharmacologic approach to male contraception remains a longstanding challenge in medicine. Toward this objective, we explored the spermatogenic effects of a selective small-molecule inhibitor (JQ1) of the bromodomain and extraterminal (BET) subfamily of epigenetic reader proteins. Here, we report potent inhibition of the testis-specific member BRDT, which is essential for chromatin remodeling during spermatogenesis. Biochemical and crystallographic studies confirm that occupancy of the BRDT acetyl-lysine binding pocket by JQ1 prevents recognition of acetylated histone H4. Treatment of mice with JQ1 reduced seminiferous tubule area, testis size, and spermatozoa number and motility without affecting hormone levels. Although JQ1-treated males mate normally, inhibitory effects of JQ1 evident at the spermatocyte and round spermatid stages cause a complete and reversible contraceptive effect. These data establish a new contraceptive that can cross the blood:testis boundary and inhibit bromodomain activity during spermatogenesis, providing a lead compound targeting the male germ cell for contraception.


Assuntos
Azepinas/farmacologia , Anticoncepcionais Masculinos/farmacologia , Proteínas Nucleares/antagonistas & inibidores , Triazóis/farmacologia , Animais , Azepinas/química , Barreira Hematotesticular , Anticoncepcionais Masculinos/química , Feminino , Humanos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Modelos Moleculares , Proteínas Nucleares/química , Estrutura Terciária de Proteína , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/citologia , Testículo/efeitos dos fármacos , Triazóis/química
2.
Pediatr Radiol ; 54(8): 1371-1390, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38520560

RESUMO

This publication provides an overview of current imaging indications and practices for patients undergoing gender-affirming surgery, with an emphasis on the importance of tailored, patient-specific care. Gender-affirming surgeries are performed with personalized approaches at various stages of life for those with intersex traits or differences in sex development (I/DSD) and transgender and gender diverse (TGD) individuals. For I/DSD patients, ultrasound, genitography, or MRI occurs during infancy and puberty to evaluate genital and gonadal anatomy. Facial harmonization involves bony and soft tissue modifications, guided by maxillofacial computerized tomography (CT) with three-dimensional reconstruction. Ultrasound is the main modality in assessing hormone-related and post-surgical changes in the chest. Imaging for genital reconstruction uses cross-sectional images and fluoroscopy to assess neoanatomy and complications.


Assuntos
Transtornos do Desenvolvimento Sexual , Cirurgia de Readequação Sexual , Humanos , Masculino , Transtornos do Desenvolvimento Sexual/diagnóstico por imagem , Feminino , Adolescente , Cirurgia de Readequação Sexual/métodos , Criança , Pessoas Transgênero
3.
J Urol ; 207(3): 694-700, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34791895

RESUMO

PURPOSE: We performed a retrospective, single-institution study to characterize the pathological findings of testis tissue specimens from older boys and adolescents with cryptorchidism. MATERIALS AND METHODS: With institutional review board approval, pathology reports were obtained for testicular specimens from patients age 10 years or older at a pediatric hospital from 1994 to 2016. Reports were excluded if they lacked clinical records, lacked testicular parenchyma, were from a descended testis or were from a patient with differences of sexual development. Variables of interest included age, testis location, procedure and pathological findings. Presence of malignancy among intra-abdominal versus extra-abdominal undescended testes was compared using Fisher's Exact Test. RESULTS: Seventy-one patients met inclusion criteria. The median age was 15.3 years (range 10.1-27.7). None had a history of testicular malignancy. Forty-five unilateral orchiectomies, 22 unilateral orchiopexies with biopsy and 4 bilateral procedures were performed. Seventeen testes (22.7%) were intra-abdominal, 42 (56.0%) were in the inguinal canal, 9 (12.0%) were at the external inguinal ring, 3 (4.0%) were in the superficial inguinal pouch and 4 (5.3%) were in the scrotum. Malignancy was detected in 2/71 patients (2.8%). By location, 2/16 patients (12.5%) with intra-abdominal testis and 0/55 patients (0%) with extra-abdominal testis demonstrated malignancy (p=0.048). CONCLUSIONS: Among males with cryptorchidism ages 10 years and older without differences of sexual development, 2/16 patients with intra-abdominal testis and 0/55 patients with extra-abdominal testis demonstrated malignancy. In older boys and adolescents, orchiectomy or biopsy is indicated for intra-abdominal testes but may not be necessary for extra-abdominal undescended testes.


Assuntos
Criptorquidismo/cirurgia , Neoplasias Testiculares/patologia , Adolescente , Criança , Hospitais Pediátricos , Humanos , Masculino , Orquiectomia , Orquidopexia , Estudos Retrospectivos , Adulto Jovem
4.
J Med Virol ; 94(11): 5434-5450, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35840493

RESUMO

Latently infected cells harboring replication-competent proviruses represent a major barrier to HIV-1 cure. One major effort to purge these cells has focused on developing the "shock and kill" approach for forcing provirus reactivation to induce cell killing by viral cytopathic effects, host immune responses, or both. We conducted kinetic and mechanistic studies of HIV-1 protein expression, virion production, and cell-to-cell virus transmission during provirus reactivation. Provirus-activated ACH-2 cells stimulated with romidepsin (RMD) or PMA produced Nef early, and then Env and Gag in parallel with the appearance of virions. Env on the surface of provirus-activated cells and cellular F-actin were critical in the formation of virological synapses to mediate cell-to-cell transmission of HIV-1 from provirus-activated cells to uninfected cells. This HIV-1 cell-to-cell transmission was substantially more efficient than transmission seen via cell-free virus spread and required F-actin remodeling and CD4, but not chemokine receptors. Resting human primary CD4+ T cells including naïve and memory subpopulations and, especially the memory CD4+ T cells, were highly susceptible to HIV-1 infection via cell-to-cell transmission. Cell-to-cell transmission of HIV-1 from provirus-activated cells was profoundly decreased by protease inhibitors (PIs) and neutralizing antibodies (nAbs) that recognize the CD4-binding site (CD4bs) such as VRC01, but not by reverse transcriptase (RT) inhibitor Emtricitabine (FTC). Therefore, our results suggest that PIs with potent blocking abilities should be used in clinical application of the "shock and kill" approach, most likely in combination with CD4bs nAbs, to prevent new HIV-1 infections.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Actinas/farmacologia , Anticorpos Neutralizantes , Antígenos CD4 , Linfócitos T CD4-Positivos , Humanos , Provírus/genética , Receptores de Quimiocinas , Latência Viral
5.
World J Urol ; 40(3): 849-855, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35034167

RESUMO

PURPOSE: To determine the prevalence of prostatic metaplasia in an expanded cohort of transmasculine individuals undergoing gender-affirming resection of vaginal tissue. METHODS: Institutional Review Board approval was obtained. Clinical records were reviewed for all transmasculine individuals undergoing vaginal tissue resection at our institution between January 2018 and July 2021. Corresponding pathology specimens were examined grossly and microscopically, including immunohistochemical stains for NKX3.1, prostate-specific antigen (PSA), and androgen receptor (AR). Vaginal specimens from three patients without androgen supplementation were used as controls. RESULTS: Twenty-one patients met inclusion criteria. The median age at surgery was 26.4 years (range 20.6-34.5 years). All patients had been assigned female gender at birth and lacked endocrine or genetic abnormalities. All were on testosterone therapy; median duration of therapy at surgery was 4.4 years (range 1.4-12.1 years). In the transmasculine group, no gross lesions were identified. Microscopically, all specimens demonstrated patchy intraepithelial glandular proliferation along the basement membrane and/or nodular proliferation of prostate-type tissue within the subepithelial stroma. On immunohistochemical staining, performed for a subset of cases, the glandular proliferation was positive for NKX3.1 (16/16 cases; 100%), PSA (12/14 cases; 85.7%), and AR (8/8 cases; 100%). Controls showed no evidence of prostatic metaplasia. CONCLUSION: One hundred percent of vaginal specimens obtained from transmasculine individuals on testosterone therapy (21/21 cases) demonstrated prostatic metaplasia. Further investigation is warranted to characterize the natural history and clinical significance of these changes. Patients seeking hormone therapy and/or gender-affirming surgery should be counseled on the findings and their yet-undetermined significance.


Assuntos
Próstata , Pessoas Transgênero , Adulto , Androgênios/uso terapêutico , Feminino , Humanos , Recém-Nascido , Masculino , Metaplasia/induzido quimicamente , Metaplasia/tratamento farmacológico , Vagina , Adulto Jovem
6.
Environ Res ; 204(Pt A): 111924, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34487695

RESUMO

This study assessed the ability of phosphorus (P) fertilizer to remediate the rhizosphere of three wild plant species (Banksia seminuda, a tree; Chloris truncata, a grass; and Hakea prostrata, a shrub) growing in a soil contaminated with total (aliphatic) petroleum hydrocarbon (TPH). Plant growth, photosynthesis (via chlorophyll fluorescence), soil microbial activity, alkane hydroxylase AlkB (aliphatic hydrocarbon-degrading) gene abundance, and TPH removal were evaluated 120 days after planting. Overall, although TPH served as an additional carbon source for soil microorganisms, the presence of TPH in soil resulted in decreased plant growth and photosynthesis. However, growth, photosynthesis, microbial activities, and AlkB gene abundance were enhanced by the application of P fertilizer, thereby increasing TPH removal rates, although the extent and optimum P dosage varied among the plant species. The highest TPH removal (64.66%) was observed in soil planted with the Poaceae species, C. truncata, and amended with 100 mg P kg-1 soil, while H. prostrata showed higher TPH removal compared to the plant belonging to the same Proteaceae family, B. seminuda. The presence of plants resulted in higher AlkB gene abundance and TPH removal relative to the unplanted control. The removal of TPH was associated directly with AlkB gene abundance (R2 > 0.9, p < 0.001), which was affected by plant identity and P levels. The results indicated that an integrated approach involving wild plant species and optimum P amendment, which was determined through experimentation using different plant species, was an efficient way to remediate soil contaminated with TPH.


Assuntos
Petróleo , Poluentes do Solo , Biodegradação Ambiental , Citocromo P-450 CYP4A/genética , Hidrocarbonetos , Fósforo , Rizosfera , Solo , Microbiologia do Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
7.
Pediatr Radiol ; 52(4): 752-764, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34355264

RESUMO

When infants are identified with a difference of sex development (DSD), a thoughtful approach to imaging is essential to appropriate clinical management. This review provides a comprehensive guide for radiologists who are tasked with performing this critical assignment. We review the embryologic basis of DSDs, with attention to the imaging findings that can indicate specific diagnoses. We also discuss techniques for optimal imaging, including strategies for identifying the gonads by US, tactics for performing genitograms with fluoroscopy and contrast-enhanced US, and the appropriate utilization of MRI. Finally, we review the clinical data and imaging findings that characterize some of the most common DSDs, including congenital adrenal hyperplasia, complete androgen insensitivity syndrome and gonadal dysgenesis.


Assuntos
Hiperplasia Suprarrenal Congênita , Transtornos do Desenvolvimento Sexual , Síndrome de Turner , Hiperplasia Suprarrenal Congênita/diagnóstico , Transtornos do Desenvolvimento Sexual/diagnóstico por imagem , Feminino , Humanos , Lactente , Masculino , Radiologistas , Desenvolvimento Sexual
8.
Int J Mol Sci ; 23(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36142120

RESUMO

High-temperature requirement A1 (HtrA1) has been identified as a disease-susceptibility gene for age-related macular degeneration (AMD) including polypoidal choroidal neovasculopathy (PCV). We characterized the underlying phenotypic changes of transgenic (Tg) mice expressing ubiquitous CAG promoter (CAG-HtrA1 Tg). In vivo imaging modalities and histopathology were performed to investigate the possible neovascularization, drusen formation, and infiltration of macrophages. Subretinal white material deposition and scattered white-yellowish retinal foci were detected on CFP [(Tg­33% (20/60) and wild-type (WT)­7% (1/15), p < 0.05]. In 40% (4/10) of the CAG-HtrA1 Tg retina, ICGA showed punctate hyperfluorescent spots. There was no leakage on FFA and OCTA failed to confirm vascular flow signals from the subretinal materials. Increased macrophages and RPE cell migrations were noted from histopathological sections. Monocyte subpopulations were increased in peripheral blood in the CAG-HtrA1 Tg mice (p < 0.05). Laser induced CNV in the CAG-HtrA1 Tg mice and showed increased leakage from CNV compared to WT mice (p < 0.05). Finally, choroidal explants of the old CAG-HtrA1 Tg mice demonstrated an increased area of sprouting (p < 0.05). Signs of subclinical inflammation was observed in CAG-HtrA1 Tg mice. Such subclinical inflammation may have resulted in increased RPE cell activation and angiogenic potential.


Assuntos
Neovascularização de Coroide , Degeneração Macular , Animais , Corioide/irrigação sanguínea , Neovascularização de Coroide/genética , Neovascularização de Coroide/patologia , Serina Peptidase 1 de Requerimento de Alta Temperatura A/genética , Inflamação/genética , Inflamação/patologia , Degeneração Macular/genética , Degeneração Macular/patologia , Camundongos , Camundongos Transgênicos , Retina/patologia
9.
Lancet Oncol ; 22(2): e57-e67, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33539754

RESUMO

Male patients with childhood, adolescent, and young adult cancer are at an increased risk for infertility if their treatment adversely affects reproductive organ function. Future fertility is a primary concern of patients and their families. Variations in clinical practice are barriers to the timely implementation of interventions that preserve fertility. As part of the PanCareLIFE Consortium, in collaboration with the International Late Effects of Childhood Cancer Guideline Harmonization Group, we reviewed the current literature and developed a clinical practice guideline for fertility preservation in male patients who are diagnosed with childhood, adolescent, and young adult cancer at age 25 years or younger, including guidance on risk assessment and available methods for fertility preservation. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to grade the available evidence and to form the recommendations. Recognising the need for global consensus, this clinical practice guideline used existing evidence and international expertise to rigorously develop transparent recommendations that are easy to use to facilitate the care of male patients with childhood, adolescent, and young adult cancer who are at high risk of fertility impairment and to enhance their quality of life.


Assuntos
Preservação da Fertilidade/tendências , Neoplasias/epidemiologia , Neoplasias/terapia , Adolescente , Adulto , Sobreviventes de Câncer , Criança , Guias como Assunto , Humanos , Masculino , Neoplasias/complicações , Neoplasias/patologia , Medição de Risco , Adulto Jovem
10.
Mol Syst Biol ; 14(4): e7390, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618636

RESUMO

Populations of isogenic cells often respond coherently to signals, despite differences in protein abundance and cell state. Previously, we uncovered processes in the Saccharomyces cerevisiae pheromone response system (PRS) that reduced cell-to-cell variability in signal strength and cellular response. Here, we screened 1,141 non-essential genes to identify 50 "variability genes". Most had distinct, separable effects on strength and variability of the PRS, defining these quantities as genetically distinct "axes" of system behavior. Three genes affected cytoplasmic microtubule function: BIM1, GIM2, and GIM4 We used genetic and chemical perturbations to show that, without microtubules, PRS output is reduced but variability is unaffected, while, when microtubules are present but their function is perturbed, output is sometimes lowered, but its variability is always high. The increased variability caused by microtubule perturbations required the PRS MAP kinase Fus3 and a process at or upstream of Ste5, the membrane-localized scaffold to which Fus3 must bind to be activated. Visualization of Ste5 localization dynamics demonstrated that perturbing microtubules destabilized Ste5 at the membrane signaling site. The fact that such microtubule perturbations cause aberrant fate and polarity decisions in mammals suggests that microtubule-dependent signal stabilization might also operate throughout metazoans.


Assuntos
Sistema de Sinalização das MAP Quinases/genética , Proteínas dos Microtúbulos/genética , Microtúbulos/genética , Análise de Célula Única , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Ciclo Celular/genética , Microtúbulos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Feromônios/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Transdução de Sinais/genética
11.
Curr Opin Urol ; 29(5): 477-480, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31232741

RESUMO

PURPOSE OF REVIEW: Long-term survival rates from childhood cancers approach 85% with many of these patients now reaching adulthood and facing the consequences of prior cancer treatment including infertility. This highlights the importance of discussing fertility risk and presenting fertility preservation options prior to initiation of cancer treatment. This article reviews the current literature on fertility preservation in adolescents, young adults, and prepubertal patients. RECENT FINDINGS: Sperm banking remains the gold standard for fertility preservation in adolescents and young adults. Testicular sperm extraction and electroejaculation may also be utilized in patients that are unable to produce a semen sample. Fertility preservation options for prepubertal patients remain experimental but recent data illustrate the potential to restore spermatogenesis using spermatogonial stem cells. SUMMARY: Fertility risk and fertility preservation options for pediatric patients should be routinely discussed at the time of cancer diagnosis. Sperm preservation should be routinely offered to adolescents and young adults at risk for infertility from cancer treatment. Preservation of prepubertal spermatogonial stem cells can be offered as an experimental option.


Assuntos
Criopreservação , Preservação da Fertilidade/métodos , Infertilidade Masculina/terapia , Neoplasias/terapia , Preservação do Sêmen , Adolescente , Criança , Consenso , Criopreservação/ética , Criopreservação/métodos , Preservação da Fertilidade/ética , Humanos , Infertilidade Masculina/etiologia , Masculino , Preservação do Sêmen/ética , Preservação do Sêmen/métodos , Adulto Jovem
13.
J Minim Invasive Gynecol ; 25(1): 76-83, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28734971

RESUMO

STUDY OBJECTIVE: To examine whether a robotic surgical platform can complement the fine motor skills of the nondominant hand, compensating for the innate difference in dexterity between surgeon's hands, thereby conferring virtual ambidexterity. DESIGN: Crossover intervention study (Canadian Task Force classification II-1). SETTING: Centers for medical simulation in 2 tertiary care hospitals of Harvard Medical School. PARTICIPANTS: Three groups of subjects were included: (1) surgical novices (medical graduates with no robotic/laparoscopic experience); (2) surgeons in training (postgraduate year 3-4 residents and fellows with intermediate robotic and laparoscopic experience); and (3) advanced surgeons (attending surgeons with extensive robotic and laparoscopic experience). INTERVENTIONS: Each study group completed 3 dry laboratory exercises based on exercises included in the Fundamentals of Laparoscopic Surgery (FLS) curriculum. Each exercise was completed 4 times: using the dominant and nondominant hands, on a standard laparoscopic FLS box trainer, and in a robotic dry laboratory setup. Participants were randomized to the handedness and setting order in which they tackled the tasks. MEASUREMENTS AND MAIN RESULTS: Performance was primarily measured as time to completion, with adjustments based on errors. Means of performance for the dominant versus nondominant hand for each task were calculated and compared using repeated-measures analysis of variance. A total of 36 subjects were enrolled (12 per group). In the laparoscopic setting, the mean overall time to completion of all 3 tasks with the dominant hand differed significantly from that with the nondominant hand (439.4 seconds vs 568.4 seconds; p = .0008). The between-hand performance difference was nullified with the robotic system (374.4 seconds vs 399.7 seconds; p = .48). The evaluation of performance for each individual task also revealed a statistically significant disparate performance between hands for all 3 tasks when the laparoscopic approach was used (p = .003, .02, and .01, respectively); however, no between-hand difference was observed when the tasks were performed robotically. On analysis across the 3 surgeon experience groups, the performance advantage of robotic technology remained significant for the surgical novice and intermediate-level experience groups. CONCLUSION: Robot-assisted laparoscopy may eliminate the operative handedness observed in conventional laparoscopy, allowing for virtual ambidexterity. This ergonomic advantage is particularly evident in surgical trainees. Virtual ambidexterity may represent an additional aspect of surgical robotics that facilitates mastery of minimally invasive skills.


Assuntos
Competência Clínica , Lateralidade Funcional/fisiologia , Laparoscopia/educação , Procedimentos Cirúrgicos Robóticos/métodos , Cirurgiões/educação , Adulto , Criança , Estudos Cross-Over , Currículo , Ergonomia , Feminino , Procedimentos Cirúrgicos em Ginecologia/educação , Procedimentos Cirúrgicos em Ginecologia/instrumentação , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Laparoscopia/instrumentação , Laparoscopia/métodos , Masculino , Pediatria/educação , Pediatria/instrumentação , Pediatria/métodos , Treinamento por Simulação/métodos , Análise e Desempenho de Tarefas , Procedimentos Cirúrgicos Urológicos/educação , Procedimentos Cirúrgicos Urológicos/instrumentação , Procedimentos Cirúrgicos Urológicos/métodos
14.
Pediatr Radiol ; 48(8): 1155-1166, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29748933

RESUMO

Catheters are commonly used to treat and diagnose urinary tract abnormalities in the pediatric population. This pictorial essay reviews commonly placed genitourinary catheters imaged by radiography, fluoroscopy, computed tomography (CT) and ultrasonography (US). The purpose of the catheter, how the catheter is placed, and the imaging findings associated with appropriately positioned catheters as well as misplaced and displaced catheters are described. It is important for radiologists to recognize common genitourinary catheters, and be familiar with their normal and abnormal positions as displacement is often first recognized by diagnostic imaging.


Assuntos
Cateteres de Demora , Cateterismo Urinário/métodos , Doenças Urológicas/diagnóstico por imagem , Doenças Urológicas/terapia , Criança , Meios de Contraste , Desenho de Equipamento , Feminino , Fluoroscopia , Humanos , Masculino , Cateterismo Urinário/efeitos adversos , Sistema Urogenital/lesões
15.
J Urol ; 207(2): 439-440, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34775794
17.
J Pediatr ; 170: 260-5.e1-2, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26746120

RESUMO

OBJECTIVE: To assess sperm retrieval rates in adolescents and young adults with Klinefelter syndrome, with the ultimate goal of improving fertility in this population. Secondary aims were to evaluate other clinical characteristics of the cohort and identify predictors of sperm retrieval. STUDY DESIGN: Patients 12-25 years of age with Klinefelter syndrome (47,XXY) were recruited at the Boston Children's Hospital. Physical examination, biochemical evaluation, scrotal ultrasonography, and semen analysis were performed. Neurocognitive data were collected. Microdissection sperm extraction (unilateral micro-testicular sperm extraction) was offered to individuals with no sperm in their ejaculates. Given the small sample size, analysis was primarily descriptive. RESULTS: Fifteen patients were enrolled. None had sperm in their ejaculates. Ten patients underwent unilateral micro-testicular sperm extraction. Sperm retrieval rate was 50%. From a neurocognitive standpoint, subjects reported problems with peers, conduct, and overall difficulties. Incidentally, one-third of the patients were found to have testicular microlithiasis and 17% of subjects with renal ultrasound imaging had bilateral renal medullary nephrocalcinosis. CONCLUSIONS: This pilot study suggests that sperm retrieval rates in adolescents and young adults with Klinefelter syndrome are comparable with those reported in older men. However, larger studies are needed to confirm our findings. The clinical significance of the scrotal and renal ultrasound findings merits further investigation. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01817296.


Assuntos
Infertilidade Masculina/diagnóstico , Síndrome de Klinefelter/complicações , Recuperação Espermática , Adolescente , Adulto , Criança , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/terapia , Síndrome de Klinefelter/diagnóstico , Masculino , Projetos Piloto , Estudos Prospectivos , Adulto Jovem
18.
J Urol ; 204(5): 1060, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32779994
19.
New Phytol ; 205(3): 1342-1349, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25367754

RESUMO

Paternal biocontainment methods (PBMs) act by preventing pollen-mediated transgene flow. They are compromised by transgene escape via the crop-maternal line. We therefore assess the efficacy of PBMs for transgenic rapeseed (Brassica napus) biocontainment across the United Kingdom by estimating crop-maternal hybridization with its two progenitor species. We used remote sensing, field surveys, agricultural statistics, and meta-analysis to determine the extent of sympatry between the crop and populations of riparian and weedy B. rapa and B. oleracea. We then estimated the incidence of crop-maternal hybridization across all settings to predict the efficacy of PBMs. Evidence of crop chloroplast capture by the progenitors was expanded to a national scale, revealing that crop-maternal gene flow occurs at widely variable rates and is dependent on both the recipient and setting. We use these data to explore the value that this kind of biocontainment can bring to genetic modification (GM) risk management in terms of reducing the impact that hybrids have on the environment rather than preventing or reducing hybrid abundance per se.


Assuntos
Brassica rapa/genética , Hibridização Genética , Cloroplastos/metabolismo , Produtos Agrícolas/genética , Cruzamentos Genéticos , Geografia , Plantas Daninhas/genética , Inquéritos e Questionários , Simpatria , Reino Unido
20.
Environ Sci Technol ; 49(2): 1138-47, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25496461

RESUMO

Environmental hypoxia can occur in both natural and occupational environments. Over the recent years, the ability of hypoxia to cause endocrine disruption via perturbations in steroid synthesis (steroidogenesis) has become increasingly clear. To further understand the molecular mechanism underlying hypoxia-induced endocrine disruption, the steroid-producing human cell line H295R was used to identify microRNAs (miRNAs) affecting steroidogenic gene expression under hypoxia. Hypoxic treatment of H295R cells resulted in the downregulation of seven steroidogenic genes and one of these, CYP19A1 (aromatase), was shown to be regulated by the transcription factor hypoxia-inducible factor-1 (HIF-1). Using bioinformatic and luciferase reporter analyses, miR-98 was identified to be a CYP19A1-targeting miRNA from a subset of HIF-1-inducible miRNAs. Gain- and loss-of-function analysis suggested that under hypoxia, the increased expression of miR-98 led to the downregulation of CYP19A1 mRNA and protein expression and that it may have contributed to a reduction in estradiol (E2) production. Intriguingly, luciferase reporter assays using deletion constructs of a proximal 5'-flanking region of miR-98 did not reveal a hypoxia-responsive element (HRE)-containing promoter. Overall, this study provided evidence for the role of miRNAs in regulating steroidogenesis and novel insights into the molecular mechanisms of hypoxia-induced endocrine disruption.


Assuntos
Aromatase/metabolismo , Regulação da Expressão Gênica , MicroRNAs/metabolismo , Esteroides/biossíntese , Regiões 3' não Traduzidas , Hipóxia Celular , Linhagem Celular , Regulação para Baixo , Estradiol/biossíntese , Estrogênios/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo
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