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1.
Auris Nasus Larynx ; 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32576390

RESUMO

OBJECTIVE: "Clinical Practice Guidelines for the Diagnosis and Management of Acute Otitis Media in Children-2018 update (2018 Guidelines)" aim to provide appropriate recommendations about the diagnosis and management of children with acute otitis media (AOM), including recurrent acute otitis media (recurrent AOM), in children under 15 years of age. These evidence-based recommendations were created with the consensus of the subcommittee members, taking into consideration unique characteristics of bacteriology and antimicrobial susceptibilities of AOM pathogens in Japan, as well as global advances in vaccines. METHODS: The subcommittee re-evaluated key clinical issues based on SCOPE (a master plan of the guidelines) and created clinical questions (CQ) about the diagnosis and management of AOM patients. A literature search of the publications from 2013 to 2016 were added to the Guidelines 2013, not only to assess the evidence on the effectiveness of vaccines, but also to provide up to date information of the bacteriology and antimicrobial susceptibilities of AOM causative pathogens in Japan. RESULTS: We have proposed guidelines for disease severity-based management of AOM patients, after classifying AOM severity into mild, moderate, and severe, based on age, clinical manifestations, and otoscopic findings. CONCLUSIONS: Precise otoscopic findings are essential for judging AOM severity, which can lead to appropriate management of AOM patients.

2.
Blood Adv ; 4(12): 2631-2639, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32556284

RESUMO

Thrombomodulin functions as an anticoagulant through thrombin binding and protein C activation. We herein report the first case of hereditary functional thrombomodulin deficiency presenting with recurrent subcutaneous hemorrhage and old cerebral infarction. The patient had a homozygous substitution of glycine by aspartate at amino acid residue 412 (Gly412Asp) in the thrombin-binding domain of the thrombomodulin gene (designated thrombomodulin-Nagasaki). In vitro assays using a recombinant thrombomodulin with the same mutation as the patient showed a total lack of thrombin binding and activation of protein C and thrombin-activatable fibrinolysis inhibitor (TAFI). Marked clinical and laboratory improvement was obtained with recombinant human soluble thrombomodulin therapy.

3.
Biochem Biophys Res Commun ; 528(3): 612-619, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32505344

RESUMO

Substantial evidence has linked dehydroepiandrosterone (DHEA) levels to the anti-obesity and anti-diabetic effects of exercise. While 5'-adenosine monophosphate-activated protein kinase (AMPK) is a negative regulator of adipocyte differentiation and lipid accumulation, activation of mammalian target of rapamycin complex 1 (mTORC1), which is inhibited by AMPK, is required for adipocyte differentiation and positively regulates lipid accumulation. DHEA treatment activates the AMPK pathway in C2C12 myotubes. Hence, DHEA addition to preadipocytes and adipocytes might activate AMPK and inhibit mTORC1, resulting in the inhibition of adipogenesis and lipid accumulation. Therefore, we investigated the effect of DHEA on the AMPK pathway, mTORC1 activity, adipocyte differentiation, and lipid accumulation in 3T3-L1 cells. DHEA suppressed lipid accumulation and adipogenic marker expression during differentiation. It also activated AMPK signaling in preadipocytes and adipocytes and suppressed mTORC1 activity during differentiation. These results suggest that the activation of the AMPK pathway and inhibition of mTORC1 activity may mediate the anti-obesity effect of DHEA, providing novel molecular-level insights into its physiological functions.

4.
J Cardiovasc Electrophysiol ; 31(7): 1597-1605, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32367545

RESUMO

INTRODUCTION: There are limited data focusing on pulmonary vein (PV) narrowing following ablation using a visually guided laser balloon (VGLB). We sought to assess the frequency and predictors of PV narrowing after VGLB ablation. METHODS AND RESULTS: Patients with paroxysmal atrial fibrillation treated with VGLB were screened. Study participants underwent contrast-enhanced computed tomography (CT) scanning before and 6 months after the procedure. We defined 25% to 49%, 50% to 74%, and 75% to 100% reduction in PV cross-sectional area as mild, moderate, and severe narrowing, respectively. Of 146 PVs in 38 patients analyzed, severe narrowing developed in two right superior and one right inferior PV. Moderate or severe narrowing occurred in 40 veins (27% of all PVs, 50% of the right superior, 22% of the right inferior, 21% of the left superior, and 14% of the left inferior PV). In PVs with moderate-severe narrowing, the baseline orifice area was significantly larger (4.1 [interquartile range, 3.2-4.8] vs 2.5 [1.9-3.3] cm2 , P < .0001), the narrowest region of stenosis was significantly more distal into the vessel (1.9 [0.7-2.9] vs 0 [0-1.7] mm from the orifice, P = .0006) and the total amount of energy delivered per vein was significantly greater (5190 ± 970 vs 4626 ± 1573 J, P = .018) than in PVs with mild or no significant narrowing. The baseline orifice area independently predicted moderate-severe narrowing in multivariate analysis (odds ratio, 1.8 [1.3-2.5] per 1 cm2 increase, P = .0003). No patient exhibited any signs or symptoms of PV stenosis. CONCLUSIONS: Baseline PV orifice area, ablating distally inside the veins, and total amount of laser energy are associated with PV narrowing after VGLB ablation.

5.
J Bone Miner Metab ; 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350615

RESUMO

INTRODUCTION: Disuse-induced bone loss is caused by a suppression of osteoblastic bone formation and an increase in osteoclastic bone resorption. There are few data available for the effects of environmental conditions, i.e., atmospheric pressure and/or oxygen concentration, on osteoporosis. This study examined the effects of mild hyperbaric oxygen at 1317 hPa with 40% oxygen on unloading-induced osteoporosis. MATERIALS AND METHODS: Eighteen 8-week old male Wistar rats were randomly divided into three groups: the control for 21 days without unloading and mild hyperbaric oxygen (NOR, n = 6), the unloading for 21 days and recovery for 10 days without mild hyperbaric oxygen (HU + NOR, n = 6), and the unloading for 21 days and recovery for 10 days with mild hyperbaric oxygen (HU + MHO, n = 6). RESULTS: The cortical thickness and trabecular bone surface area were decreased in the HU + NOR group compared to the NOR group. There were no differences between the NOR and HU + MHO groups. Osteoclast surface area and Sclerostin (Sost) mRNA expression levels were decreased in the HU + MHO group compared to the HU + NOR group. These results suggested that the loss of the cortical and trabecular bone is inhibited by mild hyperbaric oxygen, because of an inhibition of osteoclasts and enhancement of bone formation with decreased Sost expression. CONCLUSIONS: We conclude that exposure to mild hyperbaric oxygen partially protects from the osteoporosis induced by hindlimb unloading.

6.
Biochem Biophys Res Commun ; 527(1): 146-152, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32446358

RESUMO

The mitochondrial translation process, in which mitochondrial DNA (mtDNA)-encoded genes are translated into their corresponding proteins, is crucial for mitochondrial function, biogenesis, and integrity. This process is divided into four phases-initiation, elongation, termination, and mitoribosome recycling-which are regulated by specific translation factors, including mitochondrial initiation factor 2 and 3 (mtIF2 and mtIF3), mitochondrial elongation factor Tu, Ts, and G1 (mtEFTu, mtEFTs, and mtEFG1), mitochondrial translational release factor 1-like (mtRF1L), and mitochondrial recycling factor 1 and 2 (mtRRF1 and mtRRF2). Muscle denervation downregulates mitochondrial biomass and induces skeletal muscle atrophy. However, it is unknown whether denervation affects the expression of mitochondrial translation factors in skeletal muscle. In this study, we hypothesized that denervation decreases the expression of mitochondrial translation factors. Therefore, we investigated the effect of muscle denervation on mitochondrial protein and mitochondrial translation factor expression in soleus muscle after surgery. Denervation induced muscle atrophy and activated the ubiquitin-proteasome pathway in soleus muscle. Additionally, muscle denervation decreased the expression of mitochondrial translation factors as well as nuclear DNA and mtDNA-encoded mitochondrial proteins in soleus muscle. Further, a correlation was found between the expression of mitochondrial translation factors and mtDNA-encoded proteins three and seven days after denervation. Taken together, these results demonstrated that the denervation-induced decrease in mitochondrial biogenesis corresponded with changes in mitochondrial translation factors in murine skeletal muscle, providing novel molecular-level insight into the effects of muscle denervation on the mitochondrial translation process.

8.
Nutrients ; 12(3)2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32143525

RESUMO

The aim of the present study was to comprehensively investigate physical activity (PA), nutritional status, and autonomic nervous system (ANS) activity in healthy young adults with higher levels of depressive symptoms and in sex- and age-matched controls without depressive symptoms. We recruited 35 healthy young adults with higher levels of depressive symptoms (DEP group) and 35 controls (CON group). Measurement items were daily number of steps, the duration and amount of PA ≥3 metabolic equivalents (METs), exercise habits, the consumption of tryptophan (TRP) and/or vitamin B6-rich foods, plasma levels of total TRP and vitamin B6 levels, and ANS activity. The DEP group had fewer daily steps, as well as duration and amount of PA ≥3 METs, than the CON group, while there was no difference in exercise habits. The intake frequency of TRP and/or vitamin B6-rich foods and plasma vitamin B6 levels of the DEP group were rather higher than those in the control group. Plasma TRP levels and ANS activity were comparable in the two groups. Our findings suggest that a decline in overall PA, including daily steps as well as duration and amount of moderate-to-vigorous-intensity PA, could be associated with higher levels of depressive symptoms in healthy young adults. Their dietary intake of TRP and/or vitamin B6-rich foods was adequate, and there was no ANS activity dysfunction.

9.
JACC Clin Electrophysiol ; 6(2): 221-230, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32081227

RESUMO

OBJECTIVES: This study sought to examine clinical characteristics of procedural and long-term outcomes in patients undergoing catheter ablation (CA) of outflow tract ventricular arrhythmias (OT-VAs) over 16 years. BACKGROUND: CA is an effective treatment strategy for OT-VAs. METHODS: Patients undergoing CA for OT-VAs from 1999 to 2015 were divided into 3 periods: 1999 to 2004 (early), 2005 to 2010 (middle), and 2011 to 2015 (recent). Successful ablation site (right ventricular OT, aortic cusps/left ventricular OT, or coronary venous system/epicardium), VA morphology (right bundle branch block or left bundle branch block), and acute and clinical success rates were assessed. RESULTS: Six hundred eighty-two patients (336 female) were included (early: n = 97; middle: n = 204; recent: n = 381). Over time there was increase in use of irrigated ablation catheters and electroanatomic mapping, and more VAs were ablated from the aortic cusp/left ventricular OT or coronary venous system/epicardium (14% vs. 45% vs. 56%; p < 0.0001). Acute procedural success was achieved in 585 patients (86%) and was similar between groups (82% vs. 84% vs. 88%; p = 0.27). Clinical success was also similar between groups (86% vs. 87% vs. 88%; p = 0.94), but more patients in earlier periods required repeat ablation (18% vs. 17% vs. 9%; p = 0.02). Overall complication rate was 2% (similar between groups). CONCLUSIONS: Over a 16-year period there was an increase in patients undergoing CA for OT-VTs, with more ablations performed at non-right ventricular outflow tract locations using electroanatomic mapping and irrigated-tip catheters. Over time, single procedure success has improved and complications have remained limited.

10.
J Inflamm Res ; 12: 293-299, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31754309

RESUMO

Purpose: In rodents, dextran sulfate sodium (DSS)-induced diarrhea and colonic inflammation have similar symptoms to those of ulcerative colitis in humans. We examined the effects of exposure to mild hyperbaric oxygen (MHO) at an atmospheric pressure of 1317 hPa with 40% oxygen on DSS-induced diarrhea and colonic inflammation in rats. Methods: Five-week-old male Kyoto Apc Delta (KAD) rats (n = 12) were administered 2% DSS through drinking water for 1 week. Subsequently, DSS-treated male rats were not subjected to any further treatment (n = 6) or exposed to MHO (n = 6) for 2 weeks. Age-matched KAD rats not subjected to DSS treatment or exposed to MHO were used as the control group (n = 6). Results: Control rats did not exhibit diarrhea and colonic inflammation. However, DSS-treated rats exhibited diarrhea and colonic inflammation, regardless of exposure to MHO. Exposure to MHO for 2 weeks led to decreased incidence of diarrhea in DSS-treated rats (p < 0.05). Exposure to MHO had no effect on colonic inflammation in DSS-treated rats (p = 0.12). Conclusion: Exposure to MHO for 2 weeks can improve diarrhea but cannot attenuate colonic inflammation, possibly due to the short exposure duration (2 weeks) used in this study.

11.
Biopsychosoc Med ; 13: 26, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695730

RESUMO

Background: A majority of women from all cultures and socioeconomic levels experience myriad symptoms known as premenstrual syndrome during the days prior to menstruation. The present study investigated commonly reported symptoms in the premenstrual phase among college students. The authors further scrutinized potential factors, including subjective perceptions of health, which may be related to the premenstrual-symptom constellation. Methods: We conducted a cross-sectional survey, which included 200 participants (mean age: 19.8 ± 0.1 years old). The subjects completed a rating of their premenstrual experiences relative to 46 symptoms in eight categories of the self-reporting menstrual distress questionnaire (MDQ) to evaluate the prevalence and severity of premenstrual symptoms. The participants also answered a standardized health questionnaire regarding subjective perceptions of health, self-rating stress, lifestyle, and demographic variables. Results: Regardless of severity, the 10 symptoms most often occurring among the participants included skin disorders, irritability, fatigue, mood swings, general aches and pains, lowered school or work performance, backache, painful breasts, weight gain, and swelling. Stepwise multiple regression analysis revealed subjective perception of health (ß = 0.28; p <  0.001) and self-rating stress (ß = 0.18; p = 0.008) as the factors most strongly related to the MDQ total scores. In addition, the 19 women who evaluated themselves as "unhealthy and stressed" had greater prevalence of severe or extremely severe physical (general aches and pains) and psychosocial symptoms (confusion, lowered school or work performance, decreased efficiency, loneliness, anxiety, restlessness, mood swings, and depression), compared to the healthy and non-stressed women. Conclusions: The present study indicates the prevalence of premenstrual symptoms, regardless of severity and number, among college students and suggests that negative subjective perceptions of health and stress may be related to the intensity of premenstrual symptomatology.

12.
Foods ; 8(10)2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31557885

RESUMO

We investigated the protective effect of Brazilian propolis, a natural resinous substance produced by honeybees, against glycation stress in mouse skeletal muscles. Mice were divided into four groups: (1) Normal diet + drinking water, (2) Brazilian propolis (0.1%)-containing diet + drinking water, (3) normal diet + methylglyoxal (MGO) (0.1%)-containing drinking water, and (4) Brazilian propolis (0.1%)-containing diet + MGO (0.1%)-containing drinking water. MGO treatment for 20 weeks reduced the weight of the extensor digitorum longus (EDL) muscle and tended to be in the soleus muscle. Ingestion of Brazilian propolis showed no effect on this change in EDL muscles but tended to increase the weight of the soleus muscles regardless of MGO treatment. In EDL muscles, Brazilian propolis ingestion suppressed the accumulation of MGO-derived advanced glycation end products (AGEs) in MGO-treated mice. The activity of glyoxalase 1 was not affected by MGO, but was enhanced by Brazilian propolis in EDL muscles. MGO treatment increased mRNA expression of inflammation-related molecules, interleukin (IL)-1ß, IL-6, and toll-like receptor 4 (TLR4). Brazilian propolis ingestion suppressed these increases. MGO and/or propolis exerted no effect on the accumulation of AGEs, glyoxalase 1 activity, and inflammatory responses in soleus muscles. These results suggest that Brazilian propolis exerts a protective effect against glycation stress by inhibiting the accumulation of AGEs, promoting MGO detoxification, and reducing proinflammatory responses in the skeletal muscle. However, these anti-glycation effects does not lead to prevent glycation-induced muscle mass reduction.

13.
Nutrients ; 11(8)2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31394740

RESUMO

Exercise has beneficial effects on our health by stimulating metabolic activation of skeletal muscle contraction. Caffeine is a powerful metabolic stimulant in the skeletal muscle that has ergogenic effects, including enhanced muscle power output and endurance capacity. In the present study, we aim to characterize the metabolic signatures of contracting muscles with or without caffeine stimulation using liquid chromatography-mass spectrometry and capillary electrophoresis coupled to mass spectrometry. Isolated rat epitrochlearis muscle was incubated in the presence or absence or of 3 mM caffeine for 30 min. Electrical stimulation (ES) was used to induce tetanic contractions during the final 10 min of incubation. Principal component analysis and hierarchical clustering analysis detected 184 distinct metabolites across three experimental groups-basal, ES, and ES with caffeine (ES + C). Significance Analysis of Microarray identified a total of 50 metabolites with significant changes in expression, and 23 metabolites significantly changed between the ES and ES + C groups. Changes were observed in metabolite levels of various metabolic pathways, including the pentose phosphate, nucleotide synthesis, ß-oxidation, tricarboxylic acid cycle, and amino acid metabolism. In particular, D-ribose 5-phosphate, IMP, O-acetylcarnitine, butyrylcarnitine, L-leucine, L-valine, and L-aspartate levels were higher in the ES + C group than in the ES group. These metabolic alterations induced by caffeine suggest that caffeine accelerates contraction-induced metabolic activations, thereby contributing to muscle endurance performance and exercise benefits to our health.


Assuntos
Cafeína/farmacologia , Metabolômica , Contração Muscular/fisiologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Animais , Estimulação Elétrica , Masculino , Contração Muscular/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
14.
Sci Rep ; 9(1): 8764, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217445

RESUMO

The purpose of this study is to evaluate the accuracy for classification of hepatic tumors by characterization of T1-weighted magnetic resonance (MR) images using two radiomics approaches with machine learning models: texture analysis and topological data analysis using persistent homology. This study assessed non-contrast-enhanced fat-suppressed three-dimensional (3D) T1-weighted images of 150 hepatic tumors. The lesions included 50 hepatocellular carcinomas (HCCs), 50 metastatic tumors (MTs), and 50 hepatic hemangiomas (HHs) found respectively in 37, 23, and 33 patients. For classification, texture features were calculated, and also persistence images of three types (degree 0, degree 1 and degree 2) were obtained for each lesion from the 3D MR imaging data. We used three classification models. In the classification of HCC and MT (resp. HCC and HH, HH and MT), we obtained accuracy of 92% (resp. 90%, 73%) by texture analysis, and the highest accuracy of 85% (resp. 84%, 74%) when degree 1 (resp. degree 1, degree 2) persistence images were used. Our methods using texture analysis or topological data analysis allow for classification of the three hepatic tumors with considerable accuracy, and thus might be useful when applied for computer-aided diagnosis with MR images.

15.
JACC Clin Electrophysiol ; 5(6): 719-727, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31221360

RESUMO

OBJECTIVES: This study sought to determine the impact of repeat catheter ablation (CA) prior to hospital discharge based on inducibility of clinical ventricular tachycardia (VT) during noninvasive programmed ventricular stimulation (NIPS). BACKGROUND: Inducibility of clinical VT during NIPS performed several days after CA identifies patients at high risk of recurrence. The impact of NIPS-guided repeat CA has not been reported. METHODS: Consecutive patients with structural heart disease undergoing CA of VT followed by NIPS were studied. Clinical VT was defined by comparison with 12-lead electrocardiograms and stored implantable cardioverter-defibrillator electrograms from spontaneous VT episodes. Among those with inducible clinical VT at NIPS, VT-free survival was compared between those in whom ablation was repeated (group 1) versus those in whom ablation was not repeated (group 2) prior to hospital discharge. RESULTS: Among 469 patients (64 ± 12 years of age; 85% males; 60% ischemic), 216 patients (46%) underwent NIPS 3 days (interquartile range: 2 to 4 days) after CA. Clinical VT was induced in 45 patients (21%). Among those 45, CA was repeated in 11 patients (24%). There were no significant differences in baseline clinical or index CA characteristics between groups 1 and 2. Over a median 36-month follow-up, only 1 patient (9%) in group 1 experienced VT recurrence compared to 24 patients (71%) in group 2 (p < 0.01). In univariate Cox regression, repeat CA guided by NIPS (hazard ratio: 0.07; 95% confidence interval: 0.01 to 0.58; p = 0.01) was the only predictor of VT-free survival. CONCLUSIONS: In patients with inducible clinical VT during post-ablation NIPS, repeat CA was associated with significantly lower risk of subsequent recurrence.

16.
Cell Immunol ; 341: 103925, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31088610

RESUMO

IgA nephropathy (IgAN) is a tonsil-related disease. We previously showed that oligodeoxynucleotides with CpG (CpG-ODN) and B-cell activation factor (BAFF) are involved in hyperproduction of IgA from tonsillar mononuclear cells of patients with IgAN (IgAN-TMCs). In this study, we focused on a proliferation-inducing ligand (APRIL), homologous to BAFF. IgAN-TMCs produced more APRIL than non IgAN-TMCs in the presence of both CpG-ODN and control-ODN. TLR9 expression was higher in B-cells of IgAN-TMCs, and treatment with CpG-ODN enhanced transmembrane activator and CAML interactor (TACI) expression. IgA production from IgAN-TMCs was inhibited by APRIL neutralization antibody or TACI blocking antibody, and enhanced by co-treatment of APRIL and CpG-ODN. Serum APRIL levels were higher in patients with IgAN, and decreased after tonsillectomy. These findings suggest that APRIL is involved in the hyperproduction of IgA from IgAN-TMCs, and that CpG-ODN enhanced APRIL-induced IgA production by increasing TACI expression on B-cells of IgAN-TMCs.


Assuntos
Linfócitos B/imunologia , Glomerulonefrite por IGA/genética , Tonsila Palatina/imunologia , Proteína Transmembrana Ativadora e Interagente do CAML/genética , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Adolescente , Adulto , Idoso , Anticorpos Neutralizantes/farmacologia , Fator Ativador de Células B/genética , Fator Ativador de Células B/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/patologia , Regulação da Expressão Gênica , Glomerulonefrite por IGA/imunologia , Glomerulonefrite por IGA/patologia , Glomerulonefrite por IGA/cirurgia , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/patologia , Masculino , Pessoa de Meia-Idade , Oligodesoxirribonucleotídeos/farmacologia , Tonsila Palatina/patologia , Tonsila Palatina/cirurgia , Transdução de Sinais , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/imunologia , Tonsilectomia , Proteína Transmembrana Ativadora e Interagente do CAML/antagonistas & inibidores , Proteína Transmembrana Ativadora e Interagente do CAML/imunologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/antagonistas & inibidores , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia
17.
Heart Rhythm ; 16(8): 1174-1181, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31085181

RESUMO

BACKGROUND: In patients with ischemic ventricular tachycardia (VT), substrate may be "protected" by the posteromedial papillary muscle (PMPM), explaining failure of endocardial-only ablation. OBJECTIVE: We sought to characterize the arrhythmogenic substrate and ablation approach in patients with ischemic VT mapped to the inferior left ventricle in which endocardial ablation failed because of inaccessible substrate underlying the PMPM. METHODS: We included 10 patients with recurrent ischemic VT, evidence of inferior scar, and failed endocardial ablation. In all patients, epicardial mapping was performed via a percutaneous (n = 9) or surgical (n = 1) approach, and VT elimination was achieved by ablation opposite to the PMPM. Clinical characteristics, electrocardiographic characteristics, and procedural data were analyzed. RESULTS: In all patients, intracardiac echocardiography showed hyperechoic scar below the PMPM, and 5 exhibited a pattern characterized by subendocardial basal scar that became intramural and epicardial at distal segments. In 4 patients, VT remained inducible despite endocardial scar isolation, manifested by the absence of electrograms, dissociated potentials, and/or exit block. Eleven inducible VTs were mapped to the epicardium underlying the PMPM: 8 had a right bundle branch block configuration with variable transition, while 3 exhibited left bundle branch block with negative concordance. An inferior QS pattern was present in 10 of 11 VTs. Noninducibility was achieved in 8 patients, and 7 patients remained arrhythmia-free after a mean follow-up of 27 ± 23 months. CONCLUSION: In patients with inferior ischemic scar, VT may arise from the area underneath the PMPM, limiting endocardial ablation. Intracardiac echocardiography accurately defines the substrate distribution, and an epicardial approach may eliminate VT. A pattern of "basal-endocardial/apical-epicardial" ischemic involvement is described.

19.
J Cardiovasc Electrophysiol ; 30(6): 827-835, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30843306

RESUMO

BACKGROUND: Mitral valve prolapse (MVP) is a common valve condition and has been associated with sudden cardiac death. Premature ventricular contractions (PVCs) from the papillary muscles (PMs) may play a role as triggers for ventricular fibrillation (VF) in these patients. OBJECTIVES: To characterize the electrophysiological substrate and outcomes of catheter ablation in patients with MVP and PM PVCs. METHODS: Of 597 patients undergoing ablation of ventricular arrhythmias during the period 2012-2015, we identified 25 patients with MVP and PVCs mapped to the PMs (64% female). PVC-triggered VF was the presentation in 4 patients and a fifth patient died suddenly during follow-up. The left ventricle ejection fraction (LVEF) was 50.5% ± 11.8% and PVC burden was 24.4% ± 13.1%. A cardiac magnetic resonance imaging was performed in nine cases and areas of late gadolinium enhancement were found in four of them. A detailed LV voltage map was performed in 11 patients, three of which exhibited bipolar voltage abnormalities. Complete PVC elimination was achieved in 19 (76%) patients and a significant reduction in PVC burden was observed in two (8%). In patients in which the ablation was successful, the PVC burden decreased from 20.4% ± 10.8% to 6.3% ± 9.5% (P = 0.001). In 5/6 patients with depressed LVEF and successful ablation, the LV function improved postablation. No significant differences were identified between patients with and without VF. CONCLUSIONS: PM PVCs are a source of VF in patients with MVP and can induce PVC-mediated cardiomyopathy that reverses after PVC suppression. Catheter ablation is highly successful with more than 80% PVC elimination or burden reduction.

20.
Proteomes ; 7(1)2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30781840

RESUMO

In healthy cells, proteolysis is orderly executed to maintain basal homeostasis and normal physiology. Dyscontrol in proteolysis under severe stress condition induces cell death, but the dynamics of proteolytic regulation towards the critical phase remain unclear. Teleosts have been suggested an alternative model for the study of proteolysis under severe stress. In this study, horse mackerel (Trachurus japonicus) was used and exacerbated under severe stress conditions due to air exposure. Although the complete genome for T. japonicus is not available, a transcriptomic analysis was performed to construct a reference protein database, and the expression of 72 proteases were confirmed. Quantitative peptidomic analysis revealed that proteins related to glycolysis and muscle contraction systems were highly cleaved into peptides immediately under the severe stress. Novel analysis of the peptide terminome using a multiple linear regression model demonstrated profiles of proteolysis under severe stress. The results indicated a phase transition towards dyscontrol in proteolysis in T. japonicus skeletal muscle during air exposure. Our novel approach will aid in investigating the dynamics of proteolytic regulation in skeletal muscle of non-model vertebrates.

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