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1.
Morphologie ; 106(355): 252-259, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34924282

RESUMO

The anti-Müllerian hormone (AMH) is a heterodimeric glycoprotein belonging to the TGFb superfamily implicated in human embryonic development. This hormone was first described as allowing regression of the epithelial embryonic Müllerian structures in males, which would otherwise differentiate into the uterus and fallopian tubes. It activates a signaling pathway mediated by two transmembrane receptors. Binding of AMH to its receptor induces morphological changes leading to the degeneration of Müllerian ducts. Recently, new data has shown the role played by this hormone on structures other than the genital tract. If testicular AMH expression decreases in humans over the course of a lifetime, synthesis may persist in other tissues in adulthood. The mechanisms underlying its production have been unveiled. The aim of this review is to describe the different pathways in which AMH has been identified and plays a pivotal role.


Assuntos
Hormônio Antimülleriano , Ductos Paramesonéfricos , Masculino , Feminino , Humanos , Adulto , Hormônio Antimülleriano/metabolismo , Ductos Paramesonéfricos/metabolismo , Glicoproteínas/metabolismo , Testículo/metabolismo , Transdução de Sinais/fisiologia
2.
Hum Reprod ; 35(6): 1346-1362, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32531067

RESUMO

STUDY QUESTION: Do human granulosa cells (GCs) ingest and destroy apoptotic oocytes? SUMMARY ANSWER: Somatic GCs ingest and destroy apoptotic oocytes and other apoptotic substrates through unconventional autophagy-assisted phagocytosis. WHAT IS KNOWN ALREADY: Most (99%) ovarian germ cells undergo apoptosis through follicular atresia. The mode of cleaning of atretic follicles from the ovary is unclear. Ovarian GCs share striking similarities with testicular Sertoli cells with respect to their origin and function. Somatic Sertoli cells are responsible for the elimination of apoptotic spermatogenic cells through unconventional autophagy-assisted phagocytosis. STUDY DESIGN, SIZE, DURATION: Human GCs were tested for the ability to ingest and destroy the apoptotic oocytes and other apoptotic substrates. A systemic study of the main phagocytosis steps has been performed at different time points after loading of apoptotic substrates into the GC. PARTICIPANTS/MATERIALS, SETTING, METHODS: Primary cultures of GC retrieved following controlled ovarian stimulation of five women for IVF/ICSI and a human granulosa KGN cell line were incubated with different apoptotic substrates: oocytes which underwent spontaneous apoptosis during the cultivation of immature germ cells for IVF/ICSI; apoptotic KGN cells; and apoptotic membranes from rat retinas. Cultured GC were analyzed for the presence of specific molecular markers characteristic of different steps of phagocytic and autophagy machineries by immunocytochemistry, confocal microscopy, transmission electron microscopy and western blotting, before and after loading with apoptotic substrates. MAIN RESULTS AND THE ROLE OF CHANCE: Incubation of human GC with apoptotic substrates resulted in their translocation in cell cytoplasm, concomitant with activation of the phagocytosis receptor c-mer proto-oncogene tyrosine kinase MERTK (P < 0.001), clumping of motor molecule myosin II, recruitment of autophagy proteins: autophagy-related protein 5 (ATG5), autophagy-related protein 6 (Beclin1) and the rise of a membrane form of microtubule-associated protein 1 light chain 3 (LC3-II) protein. Ingestion of apoptotic substrates was accompanied by increased expression of the lysosomal protease Cathepsin D (P < 0.001), and a rise of lysosomes in the GCs, as assessed by different techniques. The level of autophagy adaptor, sequestosome 1/p62 (p62) protein remained unchanged. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: The number of patients described here is limited. Also the dependence of phagocytosis on reproductive hormone status of patients should be analyzed. WIDER IMPLICATIONS OF THE FINDINGS: Removal of apoptotic oocytes by surrounding GC seems likely to be a physiological mechanism involved in follicular atresia. Proper functioning of this mechanism may be a new strategy for the treatment of ovarian dysfunctions associated with an imbalance in content of germ cells in the ovaries, such as premature ovarian failure and polycystic ovary syndrome. STUDY FUNDING/COMPETING INTEREST(S): The study was funded by Rennes Metropole (AIS 2015) and Agence de BioMédecine. This work was supported by funding from Université de Rennes1, Institut National de la Santé et de la Recherche Médicale (INSERM) and CHU de Rennes. A.B. is funded in part by the program Actions Concertées Interpasteuriennes (ACIP) and a research grant from the European Society of Pediatric Endocrinology. This work is supported by the Agence Nationale de la Recherche Grants ANR-17-CE14-0038 and ANR-10-LABX-73. The authors declare no competing interests.


Assuntos
Atresia Folicular , Células da Granulosa , Animais , Autofagia , Feminino , Humanos , Masculino , Oócitos , Fagocitose , Proto-Oncogene Mas , Ratos
4.
Morphologie ; 98(320): 1-7, 2014 Mar.
Artigo em Francês | MEDLINE | ID: mdl-24656859

RESUMO

Renal carcinomas are histologically and prognostically heterogeneous. Genomic as well as chromosomal studies of these tumors have permitted a better comprehension of molecular mechanisms implicated in their development and progression. The most frequent histological subtypes are characterized by recurrent cytogenetic abnormalities, such as the loss of the chromosome 3 short arm involving a VHL gene copy in clear cell renal carcinomas, or trisomies 7 and 17 in papillary renal cell carcinomas. New histological subtypes like renal carcinomas associated with Xp11.2 translocations have also been individualized. Besides diagnosis, some chromosomal aberrations like the loss of a short arm of chromosome 9 in different renal carcinoma histological subtypes have a worse prognostic impact. The identification of chromosomal shuffles contributes in backing histological diagnosis and in precising the individual prognosis of patients. This review describes chromosomal abnormalities associated to renal carcinomas and their impact for an accurate classification of these tumors and the evaluation of their prognosis.


Assuntos
Carcinoma/genética , Carcinoma/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Análise Citogenética , Humanos , Cariotipagem
5.
Rev Pneumol Clin ; 69(1): 50-4, 2013 Feb.
Artigo em Francês | MEDLINE | ID: mdl-23333047

RESUMO

The catamenial pneumothorax (CP) is defined as recurrent pneumothorax occurring from the day before menstruations until 72 hours after their beginning, but remains a diagnostic and therapeutic problem. We herein report the cases of two young women who presented several episodes of pneumothorax. The first patient (28 years old) underwent 18 recurrent pneumothorax before the diagnosis of CP. The video-assisted mini-thoracotomy found many diaphragmatic perforations, which were sutured after resection and biopsy. The latter patient underwent four pneumothorax before diagnosis of CP. A video-assisted mini-thoracotomy associated with pleurectomy and pleural freshening was then performed. CP is a rare entity of spontaneous pneumothorax often associated with thoracic endometriosis. The difficulty remains in diagnosis (diagnostic delay before the start of appropriate care), as well as in the treatment. Overall, CP requires a multidisciplinary approach combining pulmonology, thoracic surgery and gynecology.


Assuntos
Diafragma/patologia , Endometriose/diagnóstico , Pleura/patologia , Pneumotórax/diagnóstico , Adulto , Diagnóstico Tardio , Diafragma/cirurgia , Endometriose/cirurgia , Feminino , Humanos , Pleura/cirurgia , Pneumotórax/cirurgia , Recidiva , Fatores de Risco , Cirurgia Torácica Vídeoassistida , Toracotomia , Resultado do Tratamento
6.
Biol Neonate ; 88(2): 73-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15785018

RESUMO

OBJECTIVE: Adaptation to extra-uterine life requires dramatic increase in pulmonary blood flow. Mechanisms that induce pulmonary vasodilatation at birth are incompletely understood but include alveolar ventilation, increase in PaO2, and production of vasoactive mediators. We hypothesized that antenatal glucocorticoids (GC) increase pulmonary vasodilatation to birth-related stimuli. STUDY DESIGN: To test this hypothesis, we studied the pulmonary hemodynamic response at birth to mechanical ventilation with low (<10%) and then with high (100%) FiO2 in chronically prepared late-gestation fetal lambs treated or not by antenatal maternal steroids. RESULTS: Basal mean aortic and pulmonary artery pressure (PAP), left pulmonary blood flow, pulmonary vascular resistance (PVR), and blood gas were similar between control and dexamethasone-treated animals (GC group). During mechanical ventilation with low FiO2, mean PVR decreased by 40% in the control group (from 0.44 +/- 0.01 to 0.25 +/- 0.01 mm Hg/ml/min) and by 60% in the GC group (from 0.44 +/- 0.02 to 0.19 +/- 0.02 mm Hg/ml/min) (p < 0.01). When subsequently ventilated with 100% O2, there was no difference in PVR decrease between groups (0.15 +/- 0.02 mm Hg/ml/min in the GC group vs. 0.14 +/- 0.01 mm Hg/ml/min in the control group). CONCLUSION: Antenatal GC enhance pulmonary vasodilatation induced by alveolar ventilation at birth but do not alter the pulmonary vascular response to O2. We speculate that antenatal steroids exposure improve adaptation at birth through acceleration of both parenchymal and vascular lung maturation.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Circulação Pulmonar/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Feminino , Feto/efeitos dos fármacos , Hemodinâmica , Oxigênio/análise , Gravidez , Prenhez , Ovinos , Vasodilatação/efeitos dos fármacos
7.
Br J Anaesth ; 93(6): 818-24, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15465842

RESUMO

BACKGROUND: This experimental study was performed to determine the effects of norepinephrine on: (i) the pulmonary vascular tone during the development of pulmonary hypertension (PH) in the fetus and (ii) the circulatory adaptation at birth after chronic intrauterine PH. METHODS: Chronically instrumented fetal lambs were randomized into two groups: (i) a group with PH obtained by antenatal partial ligation of the ductus arteriosus (DA) (n=9) and (ii) a control group without DA ligation (n=6). Pulmonary vascular responses to norepinephrine (1.5 microg min(-1)) were measured in utero 7 days after surgery. At day 8 post-surgery, after delivery, animals were ventilated for 3 h with oxygen 100%. The group with PH was randomly assigned to receive norepinephrine or saline. RESULTS: Mean pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR) were higher in the PH group (P<0.01). Norepinephrine-induced decrease in PVR was more pronounced in the PH group than in the control group (63 vs 35%, respectively; P<0.01). In the PH group, the decrease in PVR during mechanical ventilation was greater in the animals receiving norepinephrine than in the animal receiving saline (from 1.05 (0.12) to 0.1 (0.02) vs from 1.04 (0.1) to 0.2 (0.04) mm Hg ml(-1) min(-1), respectively; P<0.01). After 3 h of ventilation, mean PVR in the PH lambs treated by norepinephrine was similar to those measured in the control lambs. Aortic pressure was higher in the group treated with norepinephrine. CONCLUSION: The data suggest that norepinephrine may improve post-natal pulmonary adaptation in the newborn with persistent PH both by increasing systemic vascular pressure and by increasing pulmonary blood flow.


Assuntos
Doenças Fetais/tratamento farmacológico , Hipertensão Pulmonar/tratamento farmacológico , Pulmão/efeitos dos fármacos , Norepinefrina/uso terapêutico , Vasodilatadores/uso terapêutico , Adaptação Fisiológica/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Doenças Fetais/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Hipertensão Pulmonar/fisiopatologia , Pulmão/irrigação sanguínea , Circulação Pulmonar/efeitos dos fármacos , Carneiro Doméstico , Estatísticas não Paramétricas , Resistência Vascular/efeitos dos fármacos
9.
Am J Physiol Regul Integr Comp Physiol ; 281(2): R607-14, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11448866

RESUMO

High levels of circulating catecholamines are found in the fetus, and fetal stress and birth induce a marked surge in catecholamine secretion. Little is known about the role of catecholamines on the fetal pulmonary circulation. To determine the effects of catecholamines on the pulmonary vascular tone, we tested the hemodynamic response to norepinephrine and dopamine infusion in chronically prepared late-gestation fetal lambs. We found that norepinephrine infusion (0.5 microg. kg(-1). min(-1)) increased pulmonary artery pressure (PAP) by 10 +/- 1% (P < 0.01), left pulmonary artery blood flow by 73 +/- 14% (P < 0.01), and decreased pulmonary vascular resistance (PVR) by 33 +/- 6% (P < 0.01). The pulmonary vasodilator effect of norepinephrine was abolished after nitric oxide synthase inhibition. Dopamine infusion at 5 microg. kg(-1). min(-1) did not significantly change PVR. Conversely, dopamine infusion at 10 microg. kg(-1). min(-1) increased PAP (P < 0.01) and progressively increased PVR by 30 +/- 14% (P < 0.01). These results indicate that catecholamines may modulate basal pulmonary vascular tone in the ovine fetus. We speculate that catecholamines may play a significant role in the maintenance of the fetal pulmonary circulation and in mediating changes in the transitional pulmonary circulation.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Dopamina/farmacologia , Feto/fisiologia , Norepinefrina/farmacologia , Circulação Pulmonar/fisiologia , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Inibidores Enzimáticos/farmacologia , Feminino , Nitroarginina/farmacologia , Gravidez , Circulação Pulmonar/efeitos dos fármacos , Ovinos , Resistência Vascular/efeitos dos fármacos
10.
Eur J Cardiothorac Surg ; 18(3): 328-33, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10973543

RESUMO

OBJECTIVE: Extracorporeal membrane oxygenation (ECMO) is a technique of extracorporeal oxygenation used in newborn infants with refractory hypoxemia after failure of maximal conventional medical management, when mortality risk is higher than 80%. We retrospectively reviewed all the neonates treated by ECMO between October 1991 and September 1997 in our newborn intensive care unit. METHODS: Fifty-seven patients were treated with ECMO for severe respiratory failure: congenital diaphragmatic hernia (CDH) (n=23), neonatal sepsis (NS) (n=14), meconium aspiration syndrome (MAS) (n=12), and others (n=8). Mean gestational age and birth weight were 38+/-2 weeks and 3200+/-500 g, respectively. Oxygenation index was 61+/-8. Both venovenous (n=28) or venoarterial ECMO (n=29) were used. The mean time at ECMO initiation was 47 h (range 8 h-2 months). The mean duration was 134+/-68 h. In each case of VA ECMO, carotid reconstruction was performed. Survival at 2 years was 40/57 (70%) (CDH 12/23 (52%), NS 11/14 (79%), MAS 12/12 (100%), others 5/8). Follow-up at 2 years was available in 36 survivors. RESULTS: Neurodevelopmental outcome was not related to the initial diagnosis: normal neurologic development (n=30), cerebral palsy (n=5), and neurologic developmental delay (n=1). Two patients remained oxygen dependant at 2 years, and four required surgical treatment for severe gastroesophageal reflux. Respiratory and digestive sequelae were more frequent in the CDH group (P<0.01). Patency and flow of the repaired carotid artery was assessed in 20 infants at 1 year of age using Doppler ultrasonography: normal (n=10), <50% stenosis (n=9), and >50% stenosis (n=1). CONCLUSION: ECMO increased survival of newborn infants with refractory hypoxemia. However, higher a survival rate and lower morbidity were found in non-CDH infants than in congenital diaphragmatic hernia.


Assuntos
Oxigenação por Membrana Extracorpórea , Insuficiência Respiratória/terapia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/etiologia , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/prevenção & controle , Circulação Cerebrovascular , Oxigenação por Membrana Extracorpórea/métodos , Seguimentos , Idade Gestacional , Humanos , Hipóxia/complicações , Hipóxia/mortalidade , Hipóxia/terapia , Recém-Nascido , Estudos Prospectivos , Insuficiência Respiratória/complicações , Insuficiência Respiratória/mortalidade , Taxa de Sobrevida , Ultrassonografia Doppler Transcraniana
11.
Eur J Cardiothorac Surg ; 18(3): 334-41, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10973544

RESUMO

OBJECTIVE: The purpose of this study was to examine whether inhaled nitric oxide (iNO) may change lung injury in moderate hyaline membrane disease (HMD). METHODS: Fifteen moderately premature lambs (128 days gestation, term=147 days) were randomly assigned to treatment with 20 ppm inhaled NO (n=7) from the onset of ventilation or control (n=8). Except for inhaled NO, treatments were intentionally similar to those applied in clinical situations. After porcine surfactant administration (Curosurf, 100 mg/kg), mechanical ventilator settings were modified during the course of the study to maintain PaCO(2) between 40 and 50 mmHg and post-ductal SpO(2) between 90 and 95%. The main studied parameters were gas exchanges parameters, respiratory mechanics (static compliance and functional residual capacity) and pulmonary vascular permeability and/or filtration rate indices. RESULTS: We found that 20 ppm of inhaled NO for 5 h significantly reduce ventilatory and oxygen requirements, but only during the first hour of mechanical ventilation. No increase in extravascular lung water content (5.41+/-0.96 vs. 5.46+/-1.09 ml/g bloodless dry lung in the control group and in the NO group, respectively) and no impairment of the respiratory mechanics could be found in the NO-treated group. However, inhaled NO increased the albumin lung leak index in this model (6.09+/-1.51 in the NO-treated group vs. 4.08+/-1.93 in the control group; P<0.05). CONCLUSIONS: Our results do not therefore support a detrimental effect of short-term exposure to low doses of NO inhalation in moderate HMD. However, it may induce an increase in lung vascular protein leakage. The pathophysiological consequences of this finding remain to be elucidated.


Assuntos
Sequestradores de Radicais Livres/administração & dosagem , Doença da Membrana Hialina/fisiopatologia , Pulmão/fisiopatologia , Óxido Nítrico/administração & dosagem , Troca Gasosa Pulmonar/efeitos dos fármacos , Administração por Inalação , Animais , Animais Recém-Nascidos , Gasometria , Permeabilidade Capilar/efeitos dos fármacos , Modelos Animais de Doenças , Água Extravascular Pulmonar/efeitos dos fármacos , Feminino , Humanos , Recém-Nascido , Pulmão/irrigação sanguínea , Circulação Pulmonar/fisiologia , Edema Pulmonar/fisiopatologia , Distribuição Aleatória , Respiração Artificial , Mecânica Respiratória/efeitos dos fármacos , Ovinos
12.
Arch Pediatr ; 7(2): 132-42, 2000 Feb.
Artigo em Francês | MEDLINE | ID: mdl-10701057

RESUMO

BACKGROUND: During the last ten years, new therapeutic strategies have been used in order to improve the management of congenital diaphragmatic hernia (CDH). CDH is associated with pulmonary hypoplasia, abnormal pulmonary vascular reactivity and pulmonary immaturity. Between 1985 and 1990, mechanical hyperventilation and early surgery were provided systematically. Since 1991, the management of CDH in our institution has involved a preoperative stabilization with exogenous surfactant replacement, gentle ventilation, high-frequency oscillation, nitric oxide or extracorporeal membrane oxygenation. PURPOSE: To analyse the impact of the new therapeutic strategy on the survival and outcome of newborns with CDH. METHODS: Retrospective review of all infants with CDH admitted to our institution from 1985 through 1996. Mortality and morbidity were compared between period I (1985-1990) and period II (1991-1996). RESULTS: Between 1985 and 1996, 123 neonates were admitted to our Neonatal Department. Nine of them had another severe congenital malformation and were excluded from the study. Survival was 23% (12/52) in period I and 56% (35/62) in period II (p < 0.001). In period II, complications were more frequent among survivors in whom an extracorporeal membrane oxygenation was required (13 infants): bronchopulmonary dysplasia 77% (10/13), gastroesophageal reflux 61% (8/13), and hypotrophy 61% (8/13). CONCLUSION: These data demonstrate a significant improvement in survival in CDH since the implementation of new therapeutic modalities. Nevertheless, a significant morbidity exists among the infants who survive a severe respiratory failure.


Assuntos
Hérnias Diafragmáticas Congênitas , Displasia Broncopulmonar/complicações , Oxigenação por Membrana Extracorpórea , Maturidade dos Órgãos Fetais , França , Refluxo Gastroesofágico/congênito , Hérnia Diafragmática/cirurgia , Hérnia Diafragmática/terapia , Ventilação em Jatos de Alta Frequência , Humanos , Recém-Nascido , Pulmão/anormalidades , Pulmão/irrigação sanguínea , Pulmão/embriologia , Hipotonia Muscular/congênito , Óxido Nítrico/uso terapêutico , Surfactantes Pulmonares/uso terapêutico , Respiração Artificial/métodos , Insuficiência Respiratória/complicações , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Vasodilatadores/uso terapêutico
14.
Ann Pathol ; 15(6): 438-42, 1995.
Artigo em Francês | MEDLINE | ID: mdl-8720840

RESUMO

Acinar cell carcinoma of the pancreas is a rare tumor of the exocrine pancreas that may be associated with a characteristic syndrome of disseminated fat necrosis with a bad prognosis. We report a case of this tumor occurring in a 63 year-old man who presented with polyarthralgia and panniculitis of the legs. The histological features and the differential diagnosis of acinar cell carcinoma are discussed.


Assuntos
Carcinoma de Células Acinares/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Paniculite Nodular não Supurativa/etiologia , Carcinoma de Células Acinares/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/complicações , Paniculite Nodular não Supurativa/patologia
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