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1.
Mol Cell ; 84(7): 1321-1337.e11, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38513662

RESUMO

Intracellular Mg2+ (iMg2+) is bound with phosphometabolites, nucleic acids, and proteins in eukaryotes. Little is known about the intracellular compartmentalization and molecular details of Mg2+ transport into/from cellular organelles such as the endoplasmic reticulum (ER). We found that the ER is a major iMg2+ compartment refilled by a largely uncharacterized ER-localized protein, TMEM94. Conventional and AlphaFold2 predictions suggest that ERMA (TMEM94) is a multi-pass transmembrane protein with large cytosolic headpiece actuator, nucleotide, and phosphorylation domains, analogous to P-type ATPases. However, ERMA uniquely combines a P-type ATPase domain and a GMN motif for ERMg2+ uptake. Experiments reveal that a tyrosine residue is crucial for Mg2+ binding and activity in a mechanism conserved in both prokaryotic (mgtB and mgtA) and eukaryotic Mg2+ ATPases. Cardiac dysfunction by haploinsufficiency, abnormal Ca2+ cycling in mouse Erma+/- cardiomyocytes, and ERMA mRNA silencing in human iPSC-cardiomyocytes collectively define ERMA as an essential component of ERMg2+ uptake in eukaryotes.


Assuntos
Adenosina Trifosfatases , ATPases do Tipo-P , Animais , Camundongos , Humanos , Adenosina Trifosfatases/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Transporte Biológico , ATPases do Tipo-P/metabolismo , Cálcio/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático
3.
J Clin Invest ; 131(4)2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33586686

RESUMO

Different fat depots have different physiologic functions. In a provocative study published in this issue of the JCI, Petrosino et al. investigate the role of paracardial fat in whole-body metabolism and exercise physiology. Petrosino et al. show that paracardial fat samples from older mice or mice fed a Western diet had decreased levels of alcohol dehydrogenase 1 (ADH1). Paracardial fat samples from humans with obesity also had decreased levels of ADH1 mRNA, supporting the translational relevance. Additional experiments with Adh1-KO mice and surgical fat transplantation experiments provide additional mechanistic insight. Paracardial fat may regulate exercise performance by altering circulating metabolites and/or endocrine effects. ADH1 appears to regulate the mitochondrial content of paracardial fat, a mechanism mediated by retinaldehyde. When ADH1 is active, the paracardial fat has characteristics of brown fat, which is beneficial for exercise performance. Further research is warranted to determine the translational potential of these findings, such as whether removing paracardial fat at the time of open-heart surgery might improve recovery time by increasing exercise capacity.


Assuntos
Obesidade , Vitamina A , Tecido Adiposo Marrom , Animais , Camundongos , Obesidade/genética
4.
Nat Commun ; 11(1): 3527, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32669538

RESUMO

Ca2+ signaling in pulmonary arterial smooth muscle cells (PASMCs) plays an important role in pulmonary hypertension (PH). However, the underlying specific ion channel mechanisms remain largely unknown. Here, we report ryanodine receptor (RyR) channel activity and Ca2+ release both are increased, and association of RyR2 by FK506 binding protein 12.6 (FKBP12.6) is decreased in PASMCs from mice with chronic hypoxia (CH)-induced PH. Smooth muscle cell (SMC)-specific RyR2 knockout (KO) or Rieske iron-sulfur protein (RISP) knockdown inhibits the altered Ca2+ signaling, increased nuclear factor (NF)-κB/cyclin D1 activation and cell proliferation, and CH-induced PH in mice. FKBP12.6 KO or FK506 treatment enhances CH-induced PH, while S107 (a specific stabilizer of RyR2/FKBP12.6 complex) produces an opposite effect. In conclusion, CH causes RISP-dependent ROS generation and FKBP12.6/RyR2 dissociation, leading to PH. RISP inhibition, RyR2/FKBP12.6 complex stabilization and Ca2+ release blockade may be potentially beneficial for the treatment of PH.


Assuntos
Ciclina D1/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Hipertensão Pulmonar/metabolismo , NF-kappa B/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Proteínas de Ligação a Tacrolimo/metabolismo , Animais , Sinalização do Cálcio , Proliferação de Células , Citosol/metabolismo , Humanos , Hipóxia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Miócitos de Músculo Liso/metabolismo , Oxigênio/metabolismo , Artéria Pulmonar/patologia , Espécies Reativas de Oxigênio/metabolismo , Transtornos Respiratórios/metabolismo , Transdução de Sinais
5.
J Visc Surg ; 157(5): 410-417, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32473822

RESUMO

Neoplastic gallbladder polyps (NGP) are rare; the prevalence in the overall population is less than 10%. NGP are associated with a risk of malignant degeneration and must be distinguished from other benign gallbladder polypoid lesions that occur more frequently. NGP are adenomas and the main risk associated with their management is to fail to detect their progression to gallbladder cancer, which is associated with a particular poor prognosis. The conclusions of the recent European recommendations have a low level of evidence, based essentially on retrospective small-volume studies. Abdominal sonography is the first line study for diagnosis and follow-up for NGP. To prevent the onset of gallbladder cancer, or treat malignant degeneration in its early phases, all NGP larger than 10mm, or symptomatic, or larger than 6mm with associated risk factors for cancer (age over 50, sessile polyp, Indian ethnicity, or patient with primary sclerosing cholangitis) are indications for cholecystectomy. Apart from these situations, simple sonographic surveillance is recommended for at least five years; if the NGP increases in size by more than 2mm in size, cholecystectomy is indicated. Laparoscopic cholecystectomy is possible but if the surgeon feels that the risk of intra-operative gallbladder perforation is high, conversion to laparotomy should be preferred to avoid potential intra-abdominal tumoral dissemination. When malignant NGP is suspected (size greater than 15mm, signs of locoregional extension on imaging), a comprehensive imaging workup should be performed to search for liver extension: in this setting, radical surgery should be considered.


Assuntos
Adenoma/terapia , Neoplasias da Vesícula Biliar/terapia , Pólipos/terapia , Adenoma/diagnóstico , Adenoma/patologia , Colecistectomia/métodos , Diagnóstico Diferencial , Progressão da Doença , Neoplasias da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/patologia , Humanos , Imageamento por Ressonância Magnética , Pólipos/diagnóstico , Pólipos/patologia , Prognóstico , Ultrassonografia , Conduta Expectante
6.
Am J Physiol Heart Circ Physiol ; 318(4): H778-H786, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32142354

RESUMO

Sepsis-induced cardiomyopathy (SIC) is associated with increased patient mortality. At present, there are no specific therapies for SIC. Previous studies have reported increased reactive oxygen species (ROS) and mitochondrial dysfunction during SIC. However, a unifying mechanism remains to be defined. We hypothesized that PKCδ is required for abnormal calcium handling and cardiac mitochondrial dysfunction during sepsis and that genetic deletion of PKCδ would be protective. Polymicrobial sepsis induced by cecal ligation and puncture (CLP) surgery decreased the ejection fraction of wild-type (WT) mice but not PKCδ knockout (KO) mice. Similarly, WT cardiomyocytes exposed to lipopolysaccharide (LPS) demonstrated decreases in contractility and calcium transient amplitude that were not observed in PKCδ KO cardiomyocytes. LPS treatment decreased sarcoplasmic reticulum calcium stores in WT cardiomyocytes, which correlated with increased ryanodine receptor-2 oxidation in WT hearts but not PKCδ KO hearts after sepsis. LPS exposure increased mitochondrial ROS and decreased mitochondrial inner membrane potential in WT cardiomyocytes. This corresponded to morphologic changes consistent with mitochondrial dysfunction such as decreased overall size and cristae disorganization. Increased cellular ROS and changes in mitochondrial morphology were not observed in PKCδ KO cardiomyocytes. These data show that PKCδ is required in the pathophysiology of SIC by generating ROS and promoting mitochondrial dysfunction. Thus, PKCδ is a potential target for cardiac protection during sepsis.NEW & NOTEWORTHY Sepsis is often complicated by cardiac dysfunction, which is associated with a high mortality rate. Our work shows that the protein PKCδ is required for decreased cardiac contractility during sepsis. Mice with deletion of PKCδ are protected from cardiac dysfunction after sepsis. PKCδ causes mitochondrial dysfunction in cardiac myocytes, and reducing mitochondrial oxidative stress improves contractility in wild-type cardiomyocytes. Thus, PKCδ is a potential target for cardiac protection during sepsis.


Assuntos
Cardiomiopatias/genética , Mitocôndrias Cardíacas/metabolismo , Proteína Quinase C-delta/genética , Sepse/complicações , Animais , Sinalização do Cálcio , Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Células Cultivadas , Feminino , Deleção de Genes , Lipopolissacarídeos/toxicidade , Masculino , Potencial da Membrana Mitocondrial , Camundongos , Contração Miocárdica , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Estresse Oxidativo , Proteína Quinase C-delta/metabolismo
7.
J Visc Surg ; 157(6): 469-474, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32088182

RESUMO

INTRODUCTION: Serious caustic burns of the stomach that present with no clinico-biological severity criteria (CBSC) can be treated conservatively. However, even if there are no CBSC at admission, 20% of patients still require delayed emergency surgery for peritonitis due to gastric perforation thus showing the limitations of this strategy in the diagnosis of irreversible gastric necrosis lesions. The aim of this study was to identify reliable computed tomography (CT) signs of irreversible gastric necrosis in patients with stage 3 endoscopic lesions. PATIENTS AND METHODS: In a prospective study from March 2014 to January 2017, thoraco-abdomino-pelvic CT scan was performed in 30 consecutive patients with stage 3 endoscopic gastric lesions. The CT results were concealed from the clinicians and compared to CBSC results. RESULTS: Twenty patients were treated conservatively and ten patients were operated on. Seventy percent of the patients underwent urgent delayed surgery for symptoms that developed late but before alterations in the CBSC. The CT scan showed a perfusion defect (PD) of gastric mucosal enhancement in all patients operated on for gastrointestinal distress, and could have provided an early diagnosis of irreversible gastric necrosis. CONCLUSION: CT was a more effective diagnostic tool for the diagnosis of irreversible gastric necrosis following caustic ingestion than a strategy based on digestive endoscopy and the use of CBSC. CT could eventually replace gastrointestinal endoscopy in the emergency evaluation of gastroesophageal caustic burns.


Assuntos
Queimaduras Químicas/etiologia , Queimaduras Químicas/cirurgia , Cáusticos/intoxicação , Gastrite/induzido quimicamente , Gastrite/cirurgia , Tomografia Computadorizada por Raios X , Algoritmos , Queimaduras Químicas/diagnóstico por imagem , Feminino , Gastrite/diagnóstico por imagem , Gastroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Estudos Prospectivos , Tentativa de Suicídio/psicologia
8.
Circ Arrhythm Electrophysiol ; 12(11): e007573, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31665913

RESUMO

BACKGROUND: Obesity and diets high in saturated fat increase the risk of arrhythmias and sudden cardiac death. However, the molecular mechanisms are not well understood. We hypothesized that an increase in dietary saturated fat could lead to abnormalities of calcium homeostasis and heart rhythm by a NOX2 (NADPH oxidase 2)-dependent mechanism. METHODS: We investigated this hypothesis by feeding mice high-fat diets. In vivo heart rhythm telemetry, optical mapping, and isolated cardiac myocyte imaging were used to quantify arrhythmias, repolarization, calcium transients, and intracellular calcium sparks. RESULTS: We found that saturated fat activates NOX (NADPH oxidase), whereas polyunsaturated fat does not. The high saturated fat diet increased repolarization heterogeneity and ventricular tachycardia inducibility in perfused hearts. Pharmacological inhibition or genetic deletion of NOX2 prevented arrhythmogenic abnormalities in vivo during high statured fat diet and resulted in less inducible ventricular tachycardia. High saturated fat diet activates CaMK (Ca2+/calmodulin-dependent protein kinase) in the heart, which contributes to abnormal calcium handling, promoting arrhythmia. CONCLUSIONS: We conclude that NOX2 deletion or pharmacological inhibition prevents the arrhythmogenic effects of a high saturated fat diet, in part mediated by activation of CaMK. This work reveals a molecular mechanism linking cardiac metabolism to arrhythmia and suggests that NOX2 inhibitors could be a novel therapy for heart rhythm abnormalities caused by cardiac lipid overload.


Assuntos
Arritmias Cardíacas/etiologia , Cálcio/metabolismo , Dieta Hiperlipídica/efeitos adversos , Miócitos Cardíacos/metabolismo , NADPH Oxidase 2/metabolismo , Estresse Oxidativo , Animais , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/metabolismo , Sinalização do Cálcio , Modelos Animais de Doenças , Ecocardiografia , Eletrocardiografia , Camundongos , Miócitos Cardíacos/patologia , Oxirredução
9.
Hum Mol Genet ; 28(15): 2486-2500, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31009944

RESUMO

Mutations in LMNA encoding lamin A/C and EMD encoding emerin cause cardiomyopathy and muscular dystrophy. Lmna null mice develop these disorders and have a lifespan of 7-8 weeks. Emd null mice show no overt pathology and have normal skeletal muscle but with regeneration defects. We generated mice with germline deletions of both Lmna and Emd to determine the effects of combined loss of the encoded proteins. Mice without lamin A/C and emerin are born at the expected Mendelian ratio, are grossly normal at birth but have shorter lifespans than those lacking only lamin A/C. However, there are no major differences between these mice with regards to left ventricular function, heart ultrastructure or electrocardiographic parameters except for slower heart rates in the mice lacking both lamin A/C and emerin. Skeletal muscle is similarly affected in both of these mice. Lmna+/- mice also lacking emerin live to at least 1 year and have no significant differences in growth, heart or skeletal muscle compared to Lmna+/- mice. Deletion of the mouse gene encoding lamina-associated protein 1 leads to prenatal death; however, mice with heterozygous deletion of this gene lacking both lamin A/C and emerin are born at the expected Mendelian ratio but had a shorter lifespan than those only lacking lamin A/C and emerin. These results show that mice with combined deficiencies of three interacting nuclear envelope proteins have normal embryonic development and that early postnatal defects are primarily driven by loss of lamin A/C or lamina-associated polypeptide 1 rather than emerin.


Assuntos
Proteínas de Transporte/genética , Coração/fisiopatologia , Lamina Tipo A/genética , Proteínas de Membrana/genética , Músculo Esquelético/fisiopatologia , Distrofia Muscular de Emery-Dreifuss/genética , Mutação , Proteínas Nucleares/genética , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Feminino , Haploinsuficiência , Masculino , Camundongos , Camundongos Knockout , Músculo Esquelético/metabolismo , Distrofia Muscular de Emery-Dreifuss/fisiopatologia , Miocárdio/metabolismo , Miocárdio/patologia
10.
J Dairy Sci ; 101(2): 1638-1647, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29224860

RESUMO

The objectives of this observational study were to assess the ability of automated activity monitoring (AAM) to detect estrus for first insemination, the accuracy of detection, and the optimum interval from the estrus alert from the AAM system to insemination. Four commercial farms using 1 of 2 commercial AAM systems were studied over 1 yr. Cows were inseminated between 55 and 80 d in milk (DIM) based on AAM only, then by a combination of AAM and timed artificial insemination (AI). Blood progesterone was measured in 1,014 cows at wk 5, 7, and 9 postpartum; purulent vaginal discharge (PVD) was assessed at wk 5; and lameness and BCS at wk 7. Overall, AAM detected 83% of cows in estrus by 80 DIM. Cows that had 3 serum progesterone <1 ng/mL, had PVD, or were both lame and had BCS ≤2.5 has lesser odds of being detected in estrus by 80 DIM (62, 68, and 53%, respectively). Blood samples were collected on the day of 445 AI based on AAM and 323 timed AI. The proportion of cows not in estrus (progesterone >1 ng/mL) on the day of AI was similar between AAM (4 ± 1.8%) and timed AI (3 ± 1.2%). Managers elected, based on subjective criteria, not to inseminate 17% of cows for which an AAM estrus alert was issued, of which 43% were not in estrus. Activity data were extracted from AAM software for 1,399 AI. Onset of estrus was calculated using the same or similar data processing criteria as the AAM system. Producers recorded the time of AI. The interval from onset of estrus to AI was categorized as 0 to 8, 8 to 16, or 16 to 24 h. We found no effect of AAM system on the probability of pregnancy per AI, but noted an interaction of interval with parity. For multiparous cows, the probability of pregnancy per AI was 31%, which did not differ with the interval to AI. For primiparous cows, the odds of pregnancy were greater if AI occurred 0 to 8 h (49%) than 8 to 16 (36%) or 16 to 24 h (31%) after the estrus alert from the AAM. Automated activity monitoring can detect estrus for first AI in just over the length of 1 estrous cycle for over 80% of cows, but the remainder would likely require intervention for timely insemination. For multiparous cows, performing AI based on AAM once per day would not affect pregnancy per AI, but for primiparous cows AI within 8 h of the onset of estrus may be advantageous.


Assuntos
Bovinos/fisiologia , Estro/fisiologia , Inseminação Artificial/veterinária , Monitorização Fisiológica/veterinária , Atividade Motora , Animais , Detecção do Estro/métodos , Fazendas , Feminino , Monitorização Fisiológica/instrumentação , Gravidez , Progesterona/sangue , Fatores de Tempo
11.
Curr Pharm Teach Learn ; 9(3): 353-359, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-29233271

RESUMO

INTRODUCTION: The objective of this article is to describe the efforts of the student pharmacist organization called Know Your Medicine (KYM) as they conduct medication therapy management (MTM) for older adults and underserved communities. METHODS: Patients brought medications, immunization records, and health concerns to KYM events during academic years 2012-2013 and 2013-2014. Student pharmacists performed health screenings, created personalized medication records (PMR), made recommendations, created personal action plans (PAP), and conducted follow-up phone calls. RESULTS: Student pharmacists provided MTM services for a total of 107 patients. The mean duration of a KYM appointment was 62±21min, and student pharmacists provided a mean of 3.5±2.1 recommendations per patient. Patients had a mean age of 78±11 years, 4.5±3.2 disease states, 6.9±4.6 prescriptions, 1.9±1.9 OTC medications, and 2.8±2.6 vitamins or herbals. At the time of the follow-up phone call, a mean of 2.6±1.9 recommendations per patient had been followed. DISCUSSION AND CONCLUSIONS: Student pharmacists successfully implemented a new MTM program for older adults and underserved communities. This program can serve as an example of how other pharmacy colleges and schools might implement MTM training and real-world MTM experience for their student pharmacists.


Assuntos
Conduta do Tratamento Medicamentoso/organização & administração , Conduta do Tratamento Medicamentoso/estatística & dados numéricos , Estudantes de Farmácia , Idoso , Idoso de 80 Anos ou mais , Relações Comunidade-Instituição , Comorbidade , Prescrições de Medicamentos/estatística & dados numéricos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Educação em Farmácia , Feminino , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Polimedicação , Seguridade Social , Telefone , Fatores de Tempo
12.
JCI Insight ; 2(17)2017 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-28878116

RESUMO

Cardiomyopathy frequently complicates sepsis and is associated with increased mortality. Increased cardiac oxidative stress and mitochondrial dysfunction have been observed during sepsis, but the mechanisms responsible for these abnormalities have not been determined. We hypothesized that NADPH oxidase 2 (NOX2) activation could be responsible for sepsis-induced oxidative stress and cardiomyopathy. Treatment of isolated adult mouse cardiomyocytes with low concentrations of the endotoxin lipopolysaccharide (LPS) increased total cellular reactive oxygen species (ROS) and mitochondrial superoxide. Elevated mitochondrial superoxide was accompanied by depolarization of the mitochondrial inner membrane potential, an indication of mitochondrial dysfunction, and mitochondrial calcium overload. NOX2 inhibition decreased LPS-induced superoxide and prevented mitochondrial dysfunction. Further, cardiomyocytes from mice with genetic ablation of NOX2 did not have LPS-induced superoxide or mitochondrial dysfunction. LPS decreased contractility and calcium transient amplitude in isolated cardiomyocytes, and these abnormalities were prevented by inhibition of NOX2. LPS decreased systolic function in mice, measured by echocardiography. NOX2 inhibition was cardioprotective in 2 mouse models of sepsis, preserving systolic function after LPS injection or cecal ligation and puncture (CLP). These data show that inhibition of NOX2 decreases oxidative stress, preserves intracellular calcium handling and mitochondrial function, and alleviates sepsis-induced systolic dysfunction in vivo. Thus, NOX2 is a potential target for pharmacotherapy of sepsis-induced cardiomyopathy.


Assuntos
Cálcio/metabolismo , Cardiomiopatias/prevenção & controle , Mitocôndrias Cardíacas/metabolismo , NADPH Oxidase 2/antagonistas & inibidores , Sepse/complicações , Animais , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/etiologia , Modelos Animais de Doenças , Ecocardiografia , Lipopolissacarídeos/farmacologia , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Knockout , Miócitos Cardíacos/metabolismo , NADPH Oxidase 2/genética , Fosforilação Oxidativa , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
13.
Neuroimage Clin ; 14: 591-601, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28367403

RESUMO

Cognitive deficits in Parkinson's disease are thought to be related to altered functional brain connectivity. To date, cognitive-related changes in Parkinson's disease have never been explored with dense-EEG with the aim of establishing a relationship between the degree of cognitive impairment, on the one hand, and alterations in the functional connectivity of brain networks, on the other hand. This study was aimed at identifying altered brain networks associated with cognitive phenotypes in Parkinson's disease using dense-EEG data recorded during rest with eyes closed. Three groups of Parkinson's disease patients (N = 124) with different cognitive phenotypes coming from a data-driven cluster analysis, were studied: G1) cognitively intact patients (63), G2) patients with mild cognitive deficits (46) and G3) patients with severe cognitive deficits (15). Functional brain networks were identified using a dense-EEG source connectivity method. Pairwise functional connectivity was computed for 68 brain regions in different EEG frequency bands. Network statistics were assessed at both global (network topology) and local (inter-regional connections) level. Results revealed progressive disruptions in functional connectivity between the three patient groups, typically in the alpha band. Differences between G1 and G2 (p < 0.001, corrected using permutation test) were mainly frontotemporal alterations. A statistically significant correlation (ρ = 0.49, p < 0.001) was also obtained between a proposed network-based index and the patients' cognitive score. Global properties of network topology in patients were relatively intact. These findings indicate that functional connectivity decreases with the worsening of cognitive performance and loss of frontotemporal connectivity may be a promising neuromarker of cognitive impairment in Parkinson's disease.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiopatologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/patologia , Vias Neurais/fisiopatologia , Doença de Parkinson/complicações , Idoso , Análise de Variância , Estudos Transversais , Progressão da Doença , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Análise Espectral , Estatística como Assunto
14.
Methods Enzymol ; 588: 31-40, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28237108

RESUMO

Macroautophagy, a major lysosomal degradative pathway for cytoplasmic components, is a process that can be stimulated in response to many stressful situations including cancer treatment. The central autophagic organelle is the autophagosome, a double-membrane-bound vacuole that sequesters cytoplasmic material. The ultimate destiny of the autophagosome is fusion with the lysosomal compartment, where cargo, including proteins, is degraded. Here, we report a method to measure the lysosomal degradation of long-lived proteins along the autophagic pathway.


Assuntos
Autofagia , Lisossomos/metabolismo , Proteínas/metabolismo , Proteólise , Animais , Bioquímica/métodos , Humanos , Neoplasias/metabolismo
15.
Basic Clin Androl ; 26: 14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27833751

RESUMO

BACKGROUND: Secreting interstitial cell (Leydig cell) tumors are rare. In adults, the clinical picture and steroid levels are variable. CASE PRESENTATION: This paper presents a case of left testicular tumor, showing azoospermia with normal serum level of total testosterone, collapsed FSH and LH, and high delta4 androstenedione. Histopathological investigation revealed a Leydig cell tumor. TESE allowed spermatozoa extraction and freezing. Testicular histology found hypospermatogenesis and germ-cell aplasia with interstitial fibrosis. Surgical resection of the tumor resulted in normalization of gonadotropins and fall in serum delta4 androstenedione to subnormal levels in the postoperative period confirming that the tumor was secreting delta4 androstenedione. It was hypothesized that high delta4 androstenedione resulted in intra tumoral 17 ß-HSD overtaken by delta4 androstenedione or that 17 ß-HSD activity in the tumor was different from that of normal Leydig cells. Three months after surgery sperm analysis found a complete recovery of spermatogenesis. A spontaneous pregnancy occurred 3 months after surgery and a girl was born. CONCLUSIONS: In this case, the diagnosis of testicular Leydig cell tumor secreting delta4 androstenedione was made in a context of azoospermia.


INTRODUCTION: Les tumeurs testiculaires interstitielles (ou tumeurs testiculaires à cellules de Leydig) à expression endocrine sont rares. Chez l'adulte le tableau clinique et le bilan hormonal sont variables. PRÉSENTATION DU CAS: Cet article présente le cas d'une tumeur testiculaire gauche dans un contexte d'azoospermie. Le bilan hormonal montre des gonadotrophines effondrées, une testostéronémie normale et une delta4 androstenedione augmentée. L'examen anatomopathologique a mis en évidence une tumeur à cellule de Leydig. La TESE a permis l'extraction et la congélation de spermatozoïdes. L'histologie a retrouvé un aspect mixte d'hypospermatogenèse diminuée incomplète et d'aplasie. Dans les suites de l'orchidectomie partielle gauche les taux de gonadotrophines se sont normalisés ainsi que le taux de delta4 androstenedione. L'hypothèse physiopathologique est que l'augmentation de la delta4 androstenedione résulte de la sursaturation de la 17 ß-HSD intra-tumoral ou que l'activité de la 17 ß-HSD intra-tumoral est différente de celle dans les cellules de Leydig normales. Trois mois après la chirurgie, le spermogramme a montré une normalisation des paramètres spermatiques et une grossesse spontanée est survenue permettant la naissance d'une petite fille. CONCLUSION: Dans ce cas clinique, le diagnostic de tumeur testiculaire à cellule de Leydig sécrétant de la delta4 androstenedione a été fait dans un contexte d'azoospermie.

16.
Gynecol Obstet Fertil ; 44(9): 505-16, 2016 Sep.
Artigo em Francês | MEDLINE | ID: mdl-27475410

RESUMO

The stimulation of spermatogenesis is the best treatment of infertility for male hypogonadotropic-hypogonadism. The results are very pleasing because a real improvement of semen is sometimes obtained with spontaneous pregnants describing in the literature but after a long duration of treatment, often many months. Sometimes, the treatment improves the technical conditions of ICSI for the embryologists. Stimulation of spermatogenesis by gonadotrophins rFSH and/or hCG is the most used but others treatments, like pulsatile GnRH therapy or clomifene citrate can be used. The purpose of this review is to described the different protocols of stimulation of spermatogenesis and explain their results and finally to see if others indications of stimulation of spermatogenesis are existing.


Assuntos
Hipogonadismo/tratamento farmacológico , Infertilidade Masculina/tratamento farmacológico , Espermatogênese , Gonadotropina Coriônica/uso terapêutico , Clomifeno/uso terapêutico , Hormônio Foliculoestimulante/uso terapêutico , Hormônio Liberador de Gonadotropina/administração & dosagem , Humanos , Hipogonadismo/etiologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Infertilidade Masculina/etiologia , Masculino , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Testículo/fisiopatologia
17.
Lab Chip ; 16(7): 1157-60, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-26974287

RESUMO

The effect of mixing calcium and oxalate precursors by diffusion at miscible liquid interfaces on calcium oxalate crystalline phases, and in physiological conditions (concentrations and flow rates), is studied using a microfluidic channel. This channel has similar dimensions as the collection duct in human kidneys and serves as a biomimetic model in order to understand the formation of pathological microcalcifications.


Assuntos
Biomimética , Calcinose/patologia , Oxalato de Cálcio/química , Precipitação Química , Difusão , Rim/patologia , Técnicas Analíticas Microfluídicas , Oxalato de Cálcio/isolamento & purificação , Humanos , Técnicas Analíticas Microfluídicas/instrumentação , Tamanho da Partícula , Propriedades de Superfície
18.
PLoS One ; 11(1): e0145750, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26756466

RESUMO

Obesity and high saturated fat intake increase the risk of heart failure and arrhythmias. The molecular mechanisms are poorly understood. We hypothesized that physiologic levels of saturated fat could increase mitochondrial reactive oxygen species (ROS) in cardiomyocytes, leading to abnormalities of calcium homeostasis and mitochondrial function. We investigated the effect of saturated fat on mitochondrial function and calcium homeostasis in isolated ventricular myocytes. The saturated fatty acid palmitate causes a decrease in mitochondrial respiration in cardiomyocytes. Palmitate, but not the monounsaturated fatty acid oleate, causes an increase in both total cellular ROS and mitochondrial ROS. Palmitate depolarizes the mitochondrial inner membrane and causes mitochondrial calcium overload by increasing sarcoplasmic reticulum calcium leak. Inhibitors of PKC or NOX2 prevent mitochondrial dysfunction and the increase in ROS, demonstrating that PKC-NOX2 activation is also required for amplification of palmitate induced-ROS. Cardiomyocytes from mice with genetic deletion of NOX2 do not have palmitate-induced ROS or mitochondrial dysfunction. We conclude that palmitate induces mitochondrial ROS that is amplified by NOX2, causing greater mitochondrial ROS generation and partial depolarization of the mitochondrial inner membrane. The abnormal sarcoplasmic reticulum calcium leak caused by palmitate could promote arrhythmia and heart failure. NOX2 inhibition is a potential therapy for heart disease caused by diabetes or obesity.


Assuntos
Glicoproteínas de Membrana/antagonistas & inibidores , Glicoproteínas de Membrana/genética , Mitocôndrias/metabolismo , Miócitos Cardíacos/citologia , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/genética , Estresse Oxidativo/efeitos dos fármacos , Palmitatos/efeitos adversos , Animais , Antimicina A/química , Antioxidantes/química , Apoptose , Cálcio/metabolismo , Linhagem Celular , Transporte de Elétrons , Deleção de Genes , Ventrículos do Coração/patologia , Homeostase , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/patologia , Células Musculares/citologia , NADPH Oxidase 2 , Consumo de Oxigênio , Palmitatos/química , Proteína Quinase C/química , Espécies Reativas de Oxigênio/química , Retículo Sarcoplasmático/metabolismo , Transdução de Sinais
19.
Arch Womens Ment Health ; 19(1): 41-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25647071

RESUMO

Antenatal mental health assessment is increasingly common in high-income countries. Despite lacking evidence on validation or acceptability, the Whooley questions (modified PHQ-2) and Arroll 'help' question are used in the UK at booking (the first formal antenatal appointment) to identify possible cases of depression. This study investigated validation of the questions and women's views on assessment. Women (n = 191) booking at an inner-city hospital completed the Whooley and Arroll questions as part of their routine clinical care then completed a research questionnaire containing the Edinburgh postnatal depression scale (EPDS). A purposive subsample (n = 22) were subsequently interviewed. The Whooley questions 'missed' half the possible cases identified using the EPDS (EPDS threshold ≥ 10: sensitivity 45.7 %, specificity 92.1 %; ≥ 13: sensitivity 47.8 %, specificity 86.1 %), worsening to nine in ten when adopting the Arroll item (EPDS ≥ 10: sensitivity 9.1 %, specificity 98.2 %; ≥ 13: sensitivity 9.5 %, specificity 97.1 %). Women's accounts indicated that under-disclosure relates to the context of assessment and perceived relevance of depression to maternity services. Depression symptoms are under-identified in current local practice. While validated tools are needed that can be readily applied in routine maternity care, psychometric properties will be influenced by the context of disclosure when implemented in practice.


Assuntos
Depressão/diagnóstico , Transtorno Depressivo/diagnóstico , Programas de Rastreamento/métodos , Cuidado Pré-Natal/métodos , Testes Psicológicos , Adulto , Estudos de Coortes , Depressão/psicologia , Depressão Pós-Parto/prevenção & controle , Depressão Pós-Parto/psicologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Saúde Mental , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Gravidez , Complicações na Gravidez/prevenção & controle , Complicações na Gravidez/psicologia , Pesquisa Qualitativa , Sensibilidade e Especificidade , Inquéritos e Questionários , Reino Unido
20.
Cell Death Dis ; 6: e1769, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25996296

RESUMO

Upon activation by its ligand hepatocyte growth factor/scatter factor, the receptor tyrosine kinase Met promotes survival, proliferation, and migration of epithelial cells during embryogenesis. Deregulated Met signaling can also promote cancer progression and metastasis. Met belongs to the functional family of dependence receptors whose activity switches from pro-survival to pro-apoptotic during apoptosis upon caspase cleavage. Although apoptosis resistance is a hallmark of cancer cells, some remain sensitive to other cell death processes, including necrosis induced by calcium stress. The role and fate of Met during necrotic cell death are unknown. Following treatment with calcium ionophores, cell lines and primary cells undergo necrosis, and the full-length Met receptor is efficiently degraded. This degradation is achieved by double cleavage of Met in its extracellular domain by a metalloprotease of the A disintegrin and metalloproteinase (ADAM) family and in its intracellular domain by calpains (calcium-dependent proteases). These cleavages separate the Met extracellular region from its kinase domain, thus preventing Met activity and its potential pro-survival activity. Although the intracellular fragment is very similar to the fragment generated by caspases, it displays no pro-apoptotic property, likely because of the presence of the last few amino acids of Met, known to inhibit this pro-apoptotic function. The fragments identified here are observed in lung tumors overexpressing the Met receptor, along with fragments previously identified, suggesting that proteolytic cleavages of Met are involved in its degradation in tumor tissues. Thus, Met is a modulator of necrosis, able to protect cells when activated by its ligand but efficiently degraded by proteolysis when this process is engaged.


Assuntos
Apoptose/fisiologia , Neoplasias Pulmonares/patologia , Necrose/patologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Proteínas ADAM/metabolismo , Animais , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Calpaína/metabolismo , Caspases/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Ativação Enzimática , Células Epiteliais/metabolismo , Células HEK293 , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Ionomicina/farmacologia , Camundongos , Metástase Neoplásica/patologia , Interferência de RNA , RNA Interferente Pequeno , Transdução de Sinais
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