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1.
Hum Reprod ; 36(3): 560-570, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33393586

RESUMO

STUDY QUESTION: Does AZD5904, a myeloperoxidase inhibitor (MPOi), have any effect on human sperm function in vitro? SUMMARY ANSWER: AZD5904 improves sperm function in an in vitro model of oxidative stress (OS) and potentially offers a novel treatment approach for male infertility. WHAT IS KNOWN ALREADY: Male infertility is an underlying or contributory cause in half of all couples experiencing difficulties conceiving, yet there is currently no effective treatment or cure. OS is a common pathology in a significant proportion of infertile men. It can negatively affect sperm motility and the ability to fertilize a mature oocyte, as well as DNA integrity, and therefore represents an attractive target for therapeutic intervention. STUDY DESIGN, SIZE, DURATION: This study included population-based samples from men (23-50 years) attending Ninewells Assisted Conception Unit, Dundee for diagnostic semen analysis, July 2017-September 2018. Semen samples (n = 47) from 45 patients were used. PARTICIPANTS/MATERIALS, SETTING, METHODS: Neutrophils activated using zymosan were incubated with prepared human spermatozoa for 2 h (T2) and 24 h (T24) to create an in vitro model of OS. Parallel samples were co-incubated with AZD5904, an MPOi, to examine its effects. Sperm motility was assessed by computer-assisted sperm analysis at T2 and T24. Functional motility was assessed by sperm penetration assay. Statistical analysis was performed using GraphPad Prism. MAIN RESULTS AND THE ROLE OF CHANCE: There was no significant difference in total or progressive sperm motility between any treatment and control groups at T2 or T24. Nonetheless, significant positive effects on sperm function were observed with AZD5904, with 16/45 (35.6%) samples (with both normal and abnormal baseline semen analysis characteristics) displaying a ≥20% increase in sperm penetrated through viscous media (P < 0.003). LIMITATIONS, REASONS FOR CAUTION: This was an in vitro study. WIDER IMPLICATIONS OF THE FINDINGS: Treatment with AZD5904 resulted in significant increased sperm penetration in one of three samples treated, which is likely to represent improvement in sperm function required for fertilization. We are now planning a clinical trial to validate these results and hope that this could represent a new treatment for male infertility. STUDY FUNDING/COMPETING INTEREST(S): AZD5904 was shared through the AstraZeneca Open Innovation program. The study was funded by AstraZeneca and sponsored by the University of Dundee. Additional funding was provided by Chief Scientist Office/NHS Research Scotland (S.J.M.d.S.). A.W. and H.J.S. are both full time employees of AstraZeneca. A.W. and H.J.S. are inventors on a patent filed by AstraZeneca titled MPOi for use in medicine which includes MPOi for use in the treatment of male infertility (WO 2019/016074 Al). S.J.M.d.S. is Associate Editor of Human Reproduction and Editorial Board member of Reproduction & Fertility. C.L.R.B. is Editor of RBMO and has received lecturing fees from Merck and Ferring and is on the Scientific Advisory Panel for Ohana BioSciences. C.L.R.B. was chair of the World Health Organization Expert Synthesis Group on Diagnosis of Male infertility (2012-2016). C.L.R.B. has a patent WO2013054111 A1 issued. The other authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Infertilidade Masculina , Motilidade dos Espermatozoides , Humanos , Infertilidade Masculina/tratamento farmacológico , Masculino , Peroxidase , Escócia , Análise do Sêmen , Espermatozoides
2.
Int J Oral Maxillofac Surg ; 42(1): 89-98, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23131461

RESUMO

Salivary gland small cell carcinoma is a rare neoplasm, accounting for less than 1% of salivary gland tumours. Little is known about the epidemiologic factors and treatment of this lesion. The authors report two cases and perform a systematic literature search from 1960 to 2011 for articles on salivary gland small cell carcinoma. Once the papers were reviewed, a database was generated to analyse clinical and pathological features, treatments and outcomes, and an attempt was made to identify prognostic factors. Available data were retrieved for 44 cases which fully satisfied the inclusion criteria; the median age was 64.25 years and the male:female ratio was 2.4:1. The parotid gland was the most common site (79.6%). The overall 1-, 2- and 5-year survival rates were 75.3%, 56.4% and 36.6%, respectively. According to the present review, patient age, tumour size, distant metastasis and cytokeratin-20 positive immunostaining were all significant prognostic factors in a univariate analysis. No particular treatment approach appeared to improve survival. This work reinforces knowledge about salivary gland small cell carcinoma's epidemiologic features, and identifies new prognostic markers. The optimal management of this lesion remains controversial.


Assuntos
Carcinoma de Células Pequenas/patologia , Neoplasias Parotídeas/patologia , Neoplasias da Glândula Submandibular/patologia , Idoso , Biópsia por Agulha Fina , Carcinoma de Células Pequenas/secundário , Quimioterapia Adjuvante , Evolução Fatal , Humanos , Metástase Linfática/patologia , Imageamento por Ressonância Magnética , Masculino , Esvaziamento Cervical , Estadiamento de Neoplasias , Neoplasias Pancreáticas/secundário , Radiografia Torácica , Radioterapia Adjuvante , Tomografia Computadorizada por Raios X
3.
J Clin Endocrinol Metab ; 90(8): 4664-70, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15914527

RESUMO

CONTEXT: The regulation of germ cell proliferation and loss during human ovarian development is poorly understood. This is of particular interest at the time leading up to the formation of primordial follicles, at 18 wk gestation onward. OBJECTIVE: The objective of the study was to identify and quantify germ cell proliferation and apoptosis and expression of caspases in the human fetal ovary. DESIGN: This study was a laboratory investigation. SETTING: The study was conducted at a research institute. METHODS: Cell proliferation and apoptosis were detected using immunohistochemical localization of phosphorylated histone H3 and cleaved caspase-3, respectively. Caspases were also detected by immunoblotting. RESULTS: The overall proportion of germ cells in mitosis remained constant between 14 and 19 wk but showed increasing clustering. Caspase-2, -3, -7, -8, and -9 were detected by immunoblotting. There was a significant increase in germ cell apoptosis. A specimen of 20 wk gestation showed similar phosphorylated histone H3 but markedly lower cleaved caspase-3 expression than earlier gestations. Cleaved caspase-3 was not expressed in oocytes that had formed primordial follicles. CONCLUSIONS: These results indicate that as primordial follicle formation is initiated and progresses, there is an increase in both mitotic activity and apoptosis of those germ cells that have not reached the apparently protective environment of the primordial follicle.


Assuntos
Apoptose/fisiologia , Ovário/citologia , Ovário/embriologia , Óvulo/citologia , Caspases/metabolismo , Contagem de Células , Divisão Celular/fisiologia , Feminino , Histonas/metabolismo , Humanos , Mitose/fisiologia , Óvulo/enzimologia , Fosforilação , Gravidez
4.
Reproduction ; 129(4): 423-34, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15798017

RESUMO

The ability of an oocyte to support early embryonic development requires both nuclear and cytoplasmic maturation. We have investigated the effects of brain-derived neurotrophic factor (BDNF) on maturation of the bovine oocyte and embryo development after parthenogenetic activation. By RT-PCR and immunohistochemistry, cumulus and oocytes were shown to express mRNA and protein for BDNF and the p75 common neurotrophin receptor. However, mRNA for the BDNF-specific full length and truncated isoforms of the TrkB receptor are only detected in cumulus, suggesting that oocytes and cumulus differ in their capacity to respond to neurotrophin signalling. In in vitro maturation experiments, the proportion of cumulus oocyte complexes maturing to metaphase II was not altered by BDNF in groups lacking fetal calf serum (FCS), but was significantly lower than the positive control containing 10% FCS (P < 0.01). However, after maturation, the proportion of parthenogenetically activated oocytes forming blastocysts was highest for 10 ng/ml BDNF (24%, n = 95) followed by 100 ng/ml BDNF (18%, n = 91) and 10% FCS (15%, n = 103), which in turn were greater than no serum (10%, n = 83; P < 0.01). Maturation in the presence of a BDNF blocking antibody resulted in a blastocyst yield that was comparable to the absence of serum, and lower than in the presence of BDNF (P < 0.01). Similar effects on progression to metaphase II and blastocyst formation were observed using oocytes matured without cumulus. Together, these results provide the first evidence for a role for neurotrophins in promoting oocyte cytoplasmic competence to support embryonic development, despite being insufficient in the absence of serum to enhance nuclear maturation.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Citoplasma/química , Oócitos/química , Oogênese/fisiologia , Animais , Anticorpos Monoclonais/farmacologia , Fator Neurotrófico Derivado do Encéfalo/análise , Fator Neurotrófico Derivado do Encéfalo/genética , Bovinos , Técnicas de Cultura de Células , Meios de Cultura , Desenvolvimento Embrionário , Feminino , Imuno-Histoquímica/métodos , Metáfase , Oócitos/ultraestrutura , Partenogênese , RNA/análise , Receptor trkB/análise , Receptor trkB/genética , Estimulação Química
5.
Dev Biol ; 266(2): 334-45, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-14738881

RESUMO

The formation of the essential functional unit of the ovary, the primordial follicle, occurs during fetal life in humans. Factors regulating oogonial proliferation and interaction with somatic cells before primordial follicle formation are largely unknown. We have investigated the expression, localisation and functional effects of activin and its receptors in the human fetal ovary at 14-21 weeks gestation. Expression of mRNA for the activin betaA and betaB subunits and the activin receptors ActRIIA and ActRIIB was demonstrated by RT-PCR. Expression of betaA mRNA increased 2-fold across the gestational range examined. Activin subunits and receptors were localised by immunohistochemistry. The betaA subunit was expressed by oogonia, and the betaB subunit and activin receptors were expressed by both oogonia and somatic cells. BetaA expression was increased in larger oogonia at later gestations, but was low in oocytes within newly formed primordial follicles. Treatment of ovary fragments with activin A in vitro increased both the number of oogonia present and oogonial proliferation, as detected by bromodeoxyuridine (BrdU) incorporation. These data indicate that activin may be involved in the autocrine and paracrine regulation of germ cell proliferation in the human ovary during the crucial period of development leading up to primordial follicle formation.


Assuntos
Receptores de Activinas Tipo II/metabolismo , Ativinas/metabolismo , Células Germinativas/fisiologia , Subunidades beta de Inibinas/metabolismo , Ovário/fisiologia , Subunidades Proteicas/metabolismo , Receptores de Activinas Tipo II/genética , Ativinas/genética , Divisão Celular/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Feminino , Idade Gestacional , Humanos , Subunidades beta de Inibinas/genética , Folículo Ovariano/citologia , Folículo Ovariano/embriologia , Folículo Ovariano/metabolismo , Ovário/citologia , Ovário/embriologia , Subunidades Proteicas/genética
6.
Cloning Stem Cells ; 6(4): 375-85, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15671666

RESUMO

While not fulfilling the criterion of a "stem cell" in being capable of self-renewal, mature and fertilized oocytes are the original "toti-potent" cells, whose capacity for expansion and differentiation can only be approximated by stem cells of embryonic or adult origin in vitro. As such, the mechanisms by which oocytes acquire and manifest competence to support embryo development is of fundamental interest to efforts to control and re-specify somatic cell fate and toti-potency. This is underscored by the unparalleled capacity of oocyte cytoplasm to successfully re-specify the genetic program of animal development following cell nuclear replacement (i.e., cloning). Thus, the knowledge gained by understanding the acquisition of oocyte developmental competence could ultimately facilitate the creation of adult stem cells in vitro from terminally differentiated cells, ex ovo. In this paper, we review the concept of oocyte developmental competence, and focus on our own research and that of others implicating a role for neurotrophins in this process, and that of oocyte cell survival. Lastly we propose a role for neurotrophin signalling in embryo stem cell survival.


Assuntos
Citoplasma/fisiologia , Fatores de Crescimento Neural/fisiologia , Oócitos/citologia , Transdução de Sinais/fisiologia , Células-Tronco Totipotentes/fisiologia , Zigoto/fisiologia , Núcleo Celular/fisiologia , Sobrevivência Celular/fisiologia , Clonagem de Organismos , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Técnicas de Transferência Nuclear
7.
Rev Assoc Med Bras (1992) ; 42(1): 2-6, 1996.
Artigo em Português | MEDLINE | ID: mdl-8935667

RESUMO

UNLABELLED: The malign thyroid nodules identification, in the middle of a large number of innocent ones, by usual methods of exploration, is expensive, inespecific and of low accuracy. The fine needle aspiration biopsy, accepted in other places, is beginning to be used in our country. OBJECTIVE: To evaluate the diagnostic efficiency of 915 fine needle aspiration biopsies (FNAB) of patients with thyroid nodules in a period of 10 years at a 400 bed general teaching hospital. MATERIAL AND METHOD: 915 cytologic examinations and comparison of 126 of them with the histologic ones. RESULTS: Sensitivity, 91.2%; specificity, 47%; accuracy, 90.9%; false-positive, 3.6%; false negative, 5.5%. The proportion of neoplasms found in thyroidectomies was 20% when FNAB was not available yet and 48% after the introduction of this procedure. Patient acceptance was quite good, complications were infrequent and with no gravity. CONCLUSIONS: FNAB of the thyroid is efficient, safe, well tolerated and easily applied even in a small hospital, but its limitations must be emphasized, mainly when we analyse the negative results.


Assuntos
Nódulo da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha/métodos , Criança , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Nódulo da Glândula Tireoide/cirurgia , Tireoidectomia
8.
Mem Inst Oswaldo Cruz ; 82(1): 43-9, 1987.
Artigo em Português | MEDLINE | ID: mdl-3507565

RESUMO

From 13,196 faecal cultures made in Recife-Pernambuco during the period from 1978 to 1980, 1,720 strains of Salmonella were isolated. Serological typing on 1,387 of the isolates recognized 63 serotypes, 73.18% of which belonged to group B. The prevalent serotypes adding up to 1,231 strains (88.75% of the total of the isolates) were: S. typhimurium, S. saint-paul, S. poona, S. derby, S. agona, S. newport, S. oranienburg, S. infantis, S. tshiongwe and S. ndolo.


Assuntos
Diarreia/microbiologia , Salmonella/classificação , Adulto , Brasil , Criança , Fezes/microbiologia , Humanos , Salmonella/isolamento & purificação , Infecções por Salmonella/microbiologia , Sorotipagem
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