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1.
Europace ; 26(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954426

RESUMO

AIMS: Prior case series showed promising results for cardioneuroablation in patients with vagally induced atrioventricular blocks (VAVBs). We aimed to examine the acute procedural characteristics and intermediate-term outcomes of electroanatomical-guided cardioneuroablation (EACNA) in patients with VAVB. METHODS AND RESULTS: This international multicentre retrospective registry included data collected from 20 centres. Patients presenting with symptomatic paroxysmal or persistent VAVB were included in the study. All patients underwent EACNA. Procedural success was defined by the acute reversal of atrioventricular blocks (AVBs) and complete abolition of atropine response. The primary outcome was occurrence of syncope and daytime second- or advanced-degree AVB on serial prolonged electrocardiogram monitoring during follow-up. A total of 130 patients underwent EACNA. Acute procedural success was achieved in 96.2% of the cases. During a median follow-up of 300 days (150, 496), the primary outcome occurred in 17/125 (14%) cases with acute procedural success (recurrence of AVB in 9 and new syncope in 8 cases). Operator experience and use of extracardiac vagal stimulation were similar for patients with and without primary outcomes. A history of atrial fibrillation, hypertension, and coronary artery disease was associated with a higher primary outcome occurrence. Only four patients with primary outcome required pacemaker placement during follow-up. CONCLUSION: This is the largest multicentre study demonstrating the feasibility of EACNA with encouraging intermediate-term outcomes in selected patients with VAVB. Studies investigating the effect on burden of daytime symptoms caused by the AVB are required to confirm these findings.


Assuntos
Bloqueio Atrioventricular , Sistema de Registros , Humanos , Masculino , Feminino , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Bloqueio Atrioventricular/cirurgia , Ablação por Cateter/métodos , Fatores de Tempo , Estimulação do Nervo Vago/métodos , Técnicas Eletrofisiológicas Cardíacas , Síncope/etiologia , Recidiva , Nó Atrioventricular/cirurgia , Nó Atrioventricular/fisiopatologia
2.
Pacing Clin Electrophysiol ; 46(7): 717-720, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37335091

RESUMO

BACKGROUND: The use of left bundle branch pacing (LBBP) has dramatically increased since it was first described in 2016, but to date there are no published data on the safety of performing magnetic resonance imaging (MRI) in these patients. METHODS: Patients with LBBP who underwent MRI between January 2016 and October 2022 were retrospectively studied in our clinical center, which has a special program for imaging patients with cardiac devices. All patients underwent close cardiac monitoring throughout the MRI scans. Occurrence of arrhythmias or other adverse effects during MRI were assessed. LBBP lead parameters immediately pre- and post-MRI and at an outpatient follow-up were compared. RESULTS: Fifteen patients with LBBP underwent a total of 19 MRI sessions during the study period. Lead parameters did not significantly change after the MRI or on follow-up, which took place at a median of 91 days after the MRI. No patient developed arrhythmias during the MRI sessions, and no adverse effects such as lead dislodgement were reported. CONCLUSION: Although larger studies are necessary to verify our findings, MRI in patients with LBBP appears safe based on this initial case series.


Assuntos
Fascículo Atrioventricular , Bloqueio de Ramo , Humanos , Bloqueio de Ramo/diagnóstico por imagem , Bloqueio de Ramo/terapia , Bloqueio de Ramo/etiologia , Estimulação Cardíaca Artificial/métodos , Estudos Retrospectivos , Eletrocardiografia/métodos , Resultado do Tratamento
3.
Pacing Clin Electrophysiol ; 46(7): 583-591, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37221975

RESUMO

BACKGROUND: Bradyarrhythmias including sinus node dysfunction (SND) and atrioventricular block (AVB) can necessitate pacemaker (PPM) implantation in orthotopic heart transplant (OHT) recipients. Prior studies have shown conflicting findings regarding the effect of PPM implantation on survival. We evaluated the effect of PPM indication on long-term re-transplant-free survival in OHT patients. METHODS: We conducted a retrospective cohort study of OHT patients at UCLA Medical Center from 1985 to 2018. Indication for PPM (SND, AVB) was identified. Cox proportional hazards model with pacemaker implantation as a time-varying covariate was used to evaluate its effect on the primary endpoint of retransplant or death. We included 1609 OHTs in 1511 adult patients with median follow-up of 12 years. RESULTS: At transplant, patients were aged 53 ± 13 years and 1125 (74.5%) were male. Pacemakers were implanted in 109 (7.2%) patients; 65 for SND (4.3%) and 43 for AVB (2.8%). Repeat OHT was performed in 103 (6.4%) cases and 798 (52.8%) patients died during the follow-up period. The risk of the primary endpoint was significantly higher in patients requiring PPM for AVB (HR 3.0, 95% CI 2.1-4.2, p < .01) after controlling for age at OHT, gender, hypertension, diabetes, renal disease, history of repeat OHT, acute rejection, transplant coronary vasculopathy, and atrial fibrillation, but not PPM for SND (HR 1.0, 95% CI 0.70-1.4, p = 1.0). CONCLUSIONS: Patients who required PPM for AVB, but not SND, were at significantly higher risk of death or retransplant compared to patients who did not require PPM.


Assuntos
Fibrilação Atrial , Bloqueio Atrioventricular , Transplante de Coração , Marca-Passo Artificial , Adulto , Humanos , Masculino , Feminino , Estudos Retrospectivos , Fatores de Risco , Transplante de Coração/efeitos adversos , Bloqueio Atrioventricular/terapia , Bloqueio Atrioventricular/etiologia , Fibrilação Atrial/etiologia , Síndrome do Nó Sinusal/terapia
4.
Anim Biotechnol ; 34(5): 1822-1827, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35400297

RESUMO

The objective of this study was to evaluate the effects of supplemental levels of compound minerals (CM), which was formulated from a mixture of 300 mg calcium, 150 mg magnesium, 25 mg zinc, 15 mg iron, 4 mg manganese, and 2 mg copper per gram, on the growth performance and feed conversion ratio of Duroc × (Landrace × Yorkshire) fattening pigs. A total of 53 female pigs and 45 male pigs at 35 days of age were individually notched and randomly allocated to three treatments, including0 (basal diet), 0.5 (basal diet with 0.5 mg CM/kg feed), and 1 (basal diet with 1 mg CM/kg feed). There were three replicates for each of the three treatments with 28, 34, and 36 pigs in the first, second, and third treatments, respectively. The experiment was divided into two phases, the growing stage, and the finishing stage. Supplementation of compound minerals in the diet led to an increased average daily weight gain and improved feed conversion ratio and meat quality without effects on the lean meat percentage. An addition of 1 mg of compound minerals per 1 kg of feed is the recommended dose to improve the production performance of fattening pigs. These results suggest that the use of compound minerals could improve the growth traits of fattening pigs under tropical environmental conditions.


Assuntos
Oligoelementos , Feminino , Masculino , Suínos , Animais , Oligoelementos/farmacologia , Dieta/veterinária , Minerais/farmacologia , Carne/análise , Aumento de Peso , Ração Animal/análise , Composição Corporal
5.
J Toxicol Environ Health A ; 84(24): 987-1003, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34384338

RESUMO

Anoectochilus roxburghii Lind. (A. roxburghii) has promising anti-oxidant, hyperglycemic, hepatoprotective, and immunomodulatory activities as well as anti-tumor effects. However, the pharmacological actions of in vitro cultured plants remain to be determined. Therefore, the objective of the study was to assess in vitro cytotoxicity and in vivo potential toxicity of an extract derived from in vitro cultivated A. roxburghii, termed as iARE. The total flavonoid content and predominant flavonoid compounds of extract were identified and quantitatively analyzed. The in vitro cytotoxicity of iARE was examined using several cancer and normal cell lines. The apoptotic activity and expression of apoptosis-associated genes were also examined in MCF7 cells to determine the underlying mechanisms related to anti-proliferative effects. In vivo potential toxicity of iARE was assessed following acute and subchronic oral administration in Sprague Dawley rats. Quercetin, kaempferol, and isorhamnetin were three flavonoid components identified in iARE. The extract exerted cytotoxic effects on various cancer cells but not normal fibroblasts. Apoptosis in MCF7 cells was induced by iARE in a concentration-dependent manner associated with increased Bax/Bcl-2 ratio and reduced mitochondrial membrane potential ΔΨm, leading to release of cytochrome c, activation of caspase-3/7 and caspase-9, and cleavage of PARP. In the acute oral toxicity study, no mortality or toxicological signs were observed in rats at 1000 or 5000 mg/kg. In a subchronic oral toxicity study, iARE at a dosage of up to 1000 mg/kg produced no mortality or treatment-related adverse effects on general behavior, food intake, body weight, relative organ weights. No apparent marked changes in the histopathology of the liver and kidney were detected. Data demonstrated that iARE induced in vitro cytotoxic effects in cancer cells are associated with lackof invivo toxicity. Thus, iARE was suggested to be considered as apotential therapeutic candidate for cancer treatment.


Assuntos
Orchidaceae/química , Extratos Vegetais/toxicidade , Animais , Antineoplásicos/química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Apoptose/genética , Caspases/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/análise , Flavonoides/toxicidade , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Orchidaceae/crescimento & desenvolvimento , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Testes de Toxicidade , Proteína X Associada a bcl-2/metabolismo
6.
J Dairy Sci ; 104(8): 9037-9051, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33985777

RESUMO

The objective of this cross-sectional study was to determine the prevalence of disorders in preweaned calves in 3 regions in Germany, exemplary for structural diversity in dairy farming. A farm visit was performed on a single occasion on 731 dairy farms in the northern, eastern, and southern regions of Germany between December 2016 and July 2019. Farms differed in herd size, geographical location, and management. In the northern region, the farms had a median of 90 milking cows and were often run as full-time family businesses, partly with external workers. The eastern region tended to have larger farms (a median of 251 milking cows), which were often large-scale agricultural enterprises with employees. In the southern region, the farms had a median of 39 milking cows and were often traditional family businesses, some of these being part-time businesses. Clinical examinations were performed on 14,164 preweaned dairy calves (median 12 calves per farm) by trained veterinarians. A complete data set was available for 13,656 calves. Almost half (42.0%) of the evaluated calves were classified as being affected by at least 1 of the common calf disorders. Omphalitis (O, 20.9%; n = 2,876) and diarrhea (D, 18.5%; n = 2,670) were the most frequently recorded diagnoses, whereas respiratory diseases (RD) were observed to a lesser extent (8.7%; n = 1,100). A striking feature was the fact that 7.1% (n = 987) of the calves were affected by more than 1 disorder at the same time (multimorbidity, M). The following combinations of disorders were frequently observed: O and D (n = 596), O and RD (n = 164), and D and RD (n = 140). Disorders such as O and D, as well as M, were predominantly observed in calves aged 2 wk. A gradual increase in the frequency of RD was observed with age. For all disorders except RD, male calves were more often affected than females. Omphalitis was predominantly diagnosed in the summer months, whereas RD, D, and M were more common in the fall. We detected several statistically significant differences in the prevalence of clinical signs and disorders in preweaned dairy calves between the 3 exemplary regions. The prevalence of RD was higher in the south (10.8%) than in the north (8.2%) and east (7.4%). In the north (33.2%), O was observed more frequently than in the other regions (east: 18.9%; south: 10.5%), whereas D was found less frequently in the north (13.8%) than in the east (21.6%) and south (20.0%).


Assuntos
Doenças dos Bovinos , Indústria de Laticínios , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Estudos Transversais , Fazendas , Feminino , Alemanha/epidemiologia , Masculino , Leite , Prevalência
7.
J Cardiovasc Electrophysiol ; 31(9): 2382-2392, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32558054

RESUMO

INTRODUCTION: Cardiac sympathetic denervation (CSD) is utilized for the management of ventricular tachycardia (VT) in structural heart disease when refractory to radiofrequency ablation (RFA) or when patient/VT characteristics are not conducive to RFA. METHODS: We studied consecutive patients who underwent CSD at our institution from 2009 to 2018 with VT requiring repeat RFA post-CSD. Patient demographics, VT/procedural characteristics, and outcomes were assessed. RESULTS: Ninety-six patients had CSD, 16 patients underwent RFA for VT post-CSD. There were 15 male and 1 female patients with mean age of 54.2 ± 13.2 years. Fourteen patients had nonischemic cardiomyopathy. A mean of 2.0 ± 0.8 RFAs for VT was unsuccessful before the patient undergoing CSD. The median time between CSD and RFA was 104 days (interquartile range [IQR] = 15-241). The clinical VT cycle length was significantly increased after CSD both spontaneously on ECG and/or ICD interrogation (355 ± 73 ms pre-CSD vs. 422 ± 94 ms post-CSD, p = .001) and intraprocedurally (406 ± 86 ms pre-CSD vs. 457 ± 88 ms post-CSD, p = .03). Two patients had polymorphic and 14 had monomorphic VT (MMVT) pre-CSD, and all patients had MMVT post-CSD. The proportion of mappable, hemodynamically stable VTs increased from 35% during pre-CSD RFA to 58% during post-CSD RFA (p = .038). At median follow-up of 413 days (IQR = 43-1840) after RFA, eight patients had no further VT. CONCLUSION: RFA for recurrent MMVT post-CSD is a reasonable treatment option with intermediate-term clinical success in 50% of patients. Clinical VT cycle length was significantly increased after CSD with associated improvement in mappable, hemodynamically tolerated VT during RFA.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Adulto , Idoso , Arritmias Cardíacas/cirurgia , Ablação por Cateter/efeitos adversos , Feminino , Coração , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Simpatectomia , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/cirurgia , Resultado do Tratamento
8.
Cancer Invest ; 38(2): 85-93, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31939681

RESUMO

The identification and quantification of actionable mutations are critical for guiding targeted therapy and monitoring drug response in colorectal cancer. Liquid biopsy (LB) based on plasma cell-free DNA analysis has emerged as a noninvasive approach with many clinical advantages over conventional tissue sampling. Here, we developed a LB protocol using ultra-deep massive parallel sequencing and validated its clinical performance for detection and quantification of actionable mutations in three major driver genes (KRAS, NRAS and BRAF). The assay showed a 92% concordance for mutation detection between plasma and paired tissues and great reliability in quantification of variant allele frequency.


Assuntos
DNA Tumoral Circulante/genética , Neoplasias Colorretais/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Biópsia Líquida/métodos , Neoplasias Colorretais/sangue , GTP Fosfo-Hidrolases/genética , Humanos , Proteínas de Membrana/genética , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Reprodutibilidade dos Testes
9.
Europace ; 22(11): 1680-1687, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32830247

RESUMO

AIMS: Catheter ablation is an effective treatment for post-infarction ventricular tachycardia (VT). However, some patients may experience a worsened arrhythmia phenotype after ablation. We aimed to determine the prevalence and prognostic impact of arrhythmia exacerbation (AE) after post-infarction VT ablation. METHODS AND RESULTS: A total of 1187 consecutive patients (93% men, median age 68 years, median ejection fraction 30%) who underwent post-infarction VT ablation at six centres were included. Arrhythmia exacerbation was defined as post-ablation VT storm or incessant VT in patients without prior similar events. During follow-up (median 717 days), 426 (36%) patients experienced VT recurrence. Events qualifying as AE occurred in 67 patients (6%). Median times to VT recurrence with and without AE were 238 [interquartile range (IQR) 35-640] days and 135 (IQR 22-521) days, respectively (P = 0.25). Almost half of the patients (46%) who experienced AE experienced it within 6 months of the index procedure. Patients with AE had had longer ablation times during the ablation procedures compared to the rest of the patients (median 42 vs. 34 min, P = 0.02). Among patients with VT recurrence, the risk of death or heart transplantation was significantly higher in patients with than without AE (hazard ratio 1.99, 95% CI 1.28-3.10; P = 0.002) after adjusting for age, gender, ejection fraction, cardiac resynchronization therapy, post-ablation non-inducibility, and post-ablation amiodarone use. CONCLUSION: Arrhythmia exacerbation after ablation of infarct-related VT is infrequent but is independently associated with an adverse long-term outcome among patients who experience a VT recurrence. The mechanisms and mitigation strategies of AE after catheter ablation require further investigation.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Idoso , Ablação por Cateter/efeitos adversos , Feminino , Humanos , Infarto , Masculino , Prevalência , Prognóstico , Recidiva , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/epidemiologia , Taquicardia Ventricular/etiologia , Resultado do Tratamento
10.
Scand J Med Sci Sports ; 30(6): 1017-1023, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32077131

RESUMO

PURPOSE: Single-leg cycling exercise is one of the most potent, but underutilized, stimuli for promoting peripheral muscle respiratory capacity. Special ergometers used to facilitate single-leg cycling, while maintaining biomechanics similar to double-leg cycling, are not widely available. This lack of availability of specialized ergometers may explain why single-leg cycling has not been widely implemented as standard clinical practice. Therefore, we explored the extent to which participants could emphasize one leg and de-emphasize the other to perform "single-leg emphasis cycling" using standard cycle ergometers. METHODS: Sixteen athletic participants performed single-leg emphasis cycling, emphasizing each leg in separate trials, and double-leg cycling. Pedal forces and limb kinematics were collected and used to calculate joint-specific work and power at the ankle, knee, and hip. RESULTS: Study participants were able to produce approximately three times as much power with their emphasized leg compared to the de-emphasized leg during single-leg emphasis cycling. Ankle plantar flexion, dorsiflexion, knee extension, and hip extension work produced during single-leg emphasis cycling did not differ from those during double-leg cycling (all P > .60). Hip and knee flexion work during single-leg emphasis cycling exhibited small but significant differences (both P < .05) from double-leg cycling. CONCLUSIONS: These results demonstrate that single-leg emphasis cycling provides a convenient alternative to single-leg cycling requiring specialized ergometers, therefore, facilitating improved training in clinical and athletic populations using commonly available equipment. Further, biomechanics during single-leg emphasis cycling closely approximated double-leg cycling ensuring that training adaptations are highly applicable to double-leg cycling.


Assuntos
Atletas , Ciclismo/fisiologia , Ergometria/métodos , Perna (Membro)/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino
11.
Mol Vis ; 25: 215-221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30996590

RESUMO

Purpose: Retinoblastoma (RB) is a rare childhood malignant disorder caused by the biallelic inactivation of the RB1 gene. Early diagnosis and identification of carriers of heritable mutations in RB1 can improve disease outcome and management. In this study, we present the spectrum of mutations in the RB1 gene in Vietnamese patients with RB. Methods: Tumor RNA from 50 probands with RB, including 12 bilateral and 38 unilateral cases, was extracted. cDNA, after reverse transcription, was sequenced to identify the RNA mutation of the RB1 gene. At the genomic DNA level, mutational analysis of all RB1 exons, exon-intron boundaries, and the promoter region was conducted using PCR and direct sequencing. Multiplex ligation-dependent probe amplification (MLPA) analysis was performed for patients for whom the first two results were negative. For patients for whom either the sequencing or MLPA results were positive for a tumor mutation, patients' and their parents' blood DNA was analyzed to determine the germline mutation. Results: Forty-one different kinds of RB1 tumor mutations were identified in 41 probands (82.0%), including 11 of 12 bilateral cases (91.7%) and 30 of 38 unilateral cases (78.9%). The majority of the detected mutations were nonsense (15 different kinds), followed by frameshift (11 kinds), and splice site mutations (nine kinds). Each splice site mutation was confirmed to create a deletion of the corresponding exon with RNA sequencing. The single promoter mutation c.-197G>A was reported previously; however, both missense mutations identified in exon 6 (c.601G>C: p.A201P) and exon 22 (c.2264T>C: p.F755S) were novel. Gross deletions were detected with MLPA in three probands. The detection rate of germline mutations in bilateral and unilateral cases with mutations were 81.8% and 30.0%, respectively. Only one father out of the 20 parents tested was positive for a germline mutation. Conclusions: Mutations in the RB1 gene in Vietnamese patients were heterogeneous and highly prevalent with pathogenic truncated mutations. With advancement in therapeutics, early detection of RB is important for eye salvation.


Assuntos
Mutação , Retina/metabolismo , Neoplasias da Retina/genética , Proteínas de Ligação a Retinoblastoma/genética , Retinoblastoma/genética , Ubiquitina-Proteína Ligases/genética , Povo Asiático , Pré-Escolar , Análise Mutacional de DNA , Éxons , Feminino , Expressão Gênica , Humanos , Lactente , Íntrons , Masculino , Regiões Promotoras Genéticas , Retina/patologia , Neoplasias da Retina/etnologia , Neoplasias da Retina/patologia , Retinoblastoma/etnologia , Retinoblastoma/patologia
12.
PLoS Comput Biol ; 14(7): e1006318, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30011266

RESUMO

MicroRNAs (miRNAs) inhibit expression of target genes by binding to their RNA transcripts. It has been recently shown that RNA transcripts targeted by the same miRNA could "compete" for the miRNA molecules and thereby indirectly regulate each other. Experimental evidence has suggested that the aberration of such miRNA-mediated interaction between RNAs-called competing endogenous RNA (ceRNA) interaction-can play important roles in tumorigenesis. Given the difficulty of deciphering context-specific miRNA binding, and the existence of various gene regulatory factors such as DNA methylation and copy number alteration, inferring context-specific ceRNA interactions accurately is a computationally challenging task. Here we propose a computational method called Cancerin to identify cancer-associated ceRNA interactions. Cancerin incorporates DNA methylation, copy number alteration, gene and miRNA expression datasets to construct cancer-specific ceRNA networks. We applied Cancerin to three cancer datasets from the Cancer Genome Atlas (TCGA) project. Our results indicated that ceRNAs were enriched with cancer-related genes, and ceRNA modules in the inferred ceRNA networks were involved in cancer-associated biological processes. Using LINCS-L1000 shRNA-mediated gene knockdown experiment in breast cancer cell line to assess accuracy, Cancerin was able to predict expression outcome of ceRNA genes with high accuracy.


Assuntos
Neoplasias da Mama/genética , Simulação por Computador , Redes Reguladoras de Genes , Genes Neoplásicos , RNA Neoplásico/genética , Atlas como Assunto , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Metilação de DNA , Conjuntos de Dados como Assunto , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Proteínas de Neoplasias/metabolismo , Prognóstico , Ligação Proteica , Processamento Pós-Transcricional do RNA
13.
Soft Matter ; 15(8): 1825-1832, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30693355

RESUMO

We have investigated fine details of evaporation of free microdroplets of liquid binary mixtures comprising ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), glycerol and water. The microdroplets were kept and studied in an electrodynamic trap. Several phenomena associated with their evaporation are identified, discussed and modelled analytically. In particular, we've observed distillation at the microscale manifesting as a sigmoid transition of the evaporation rate (surface change rate). Sigmoid transition is known to be a characteristic feature for the evolution of the population (amount) with limited resources. We have shown that the transition itself can be comprehended using a stationary evaporation model under instantaneous mixing conditions. The condition is discussed and justified. The more general findings are primarily exemplified by a practical case of DEG contaminated with water by considering a humid and a dry ambient atmosphere. The influence of the composition of the droplet and the ambient atmosphere on the initial (pre-transition) stage of evaporation is considered in a general manner. Three types of conditions are discussed concerning the presence of an admixture in liquid and vapour phases (exemplified by the DEG/water system): (i) "dry" liquid - dry atmosphere, (ii) "wet" liquid - dry atmosphere, and (iii) "wet" liquid - wet atmosphere. Case (i) has been successfully verified against the theoretical prediction. Case (ii) has the requirement of considering non-stationary liquid-in-liquid diffusion. Case (iii) has led to a study of evaporation of a liquid mixture microdroplet with the more volatile component in equilibrium with its vapour.

14.
BMC Vet Res ; 15(1): 442, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31805933

RESUMO

BACKGROUND: In the past years, it became apparent that health status and performance differ considerably within dairy farms in Northern Germany. In order to obtain clues with respect to possible causes of these differences, a case-control study was performed. Case farms, which showed signs of health and performance problems, and control farms, which had none of these signs, were compared. Risk factors from different areas such as health management, housing, hygiene and nutrition were investigated as these are known to be highly influential. The aim of this study was to identify major factors within these areas that have the strongest association with health and performance problems of dairy herds in Northern Germany. RESULTS: In the final model, a lower energy density in the roughage fraction of the diet, more pens with dirty lying areas and a low ratio of cows per watering spaces were associated with a higher risk for herd health problems. Moreover, case farms were affected by infections with intestinal parasites, lungworms, liver flukes and Johne's Disease numerically more often than control farms. Case farms more often had pens with raised cubicles compared to the deep bedded stalls or straw yards found in control farms. In general, the hygiene of the floors and beddings was worse in case farms. Concerning nutrition, the microbiological and sensory quality of the provided silages was often insufficient, even in control farms. Less roughage was provided to early lactating cows and the feed was pushed to the feeding fence less frequently in case farms than in control farms. CONCLUSIONS: The results show that milk yield and health status were associated with various factors from different areas stressing the importance of all aspects of management for good animal health and performance. Moreover, this study confirmed well-known risk factors for health problems and performance losses. These should better be taken heed of in herd health management.


Assuntos
Doenças dos Bovinos/epidemiologia , Lactação , Criação de Animais Domésticos , Bem-Estar do Animal , Animais , Estudos de Casos e Controles , Bovinos , Feminino , Alemanha/epidemiologia , Fatores de Risco
15.
J Electrocardiol ; 51(6S): S83-S87, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30177367

RESUMO

BACKGROUND: Accurate and timely detection of atrial fibrillation (AF) episodes is important in primarily and secondary prevention of ischemic stroke and heart-related problems. In this work, heart rate regularity of ECG inter-beat intervals was investigated in episodes of AF and other rhythms using a wavelet leader based multifractal analysis. Our aim was to improve the detectability of AF episodes. METHODS: Inter-beat intervals from 25 ECG recordings available in the MIT-BIH atrial fibrillation database were analysed. Four types of annotated rhythms (atrial fibrillation, atrial flutter, AV junctional rhythm, and other rhythms) were available. A wavelet leader based multifractal analysis was applied to 5 min non-overlapping windows of each recording to estimate the multifractal spectrum in each window. The width of the multifractal spectrum was analysed for its discrimination power between rhythm episodes. RESULTS: In 10 of 25 recordings, the width of multifractal spectrum was significantly lower in episodes of AF than in other rhythms indicating increased regularity during AF. High classification accuracy (95%) of AF episodes was achieved using a combination of features derived from the multifractal analysis and statistical central moment features. CONCLUSIONS: An increase in the regularity of inter-beat intervals was observed during AF episodes by means of multifractal analysis. Multifractal features may be used to improve AF detection accuracy.


Assuntos
Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Eletrocardiografia/métodos , Fractais , Bases de Dados Factuais , Diagnóstico por Computador , Frequência Cardíaca/fisiologia , Humanos
16.
Med Princ Pract ; 27(6): 501-507, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30173215

RESUMO

Rheumatoid arthritis (RA) is a chronic, inflammatory, systemic autoimmune disease, affecting the joints with varying severity among patients. The risk factors include age, gender, genetics, and environmental exposure (cigarette smoking, air pollutants, and occupational). Many complications can follow, such as permanent joint damage requiring arthroplasty, rheumatoid vasculitis, and Felty syndrome requiring splenectomy if it remains unaddressed. As there is no cure for RA, the treatment goals are to reduce the pain and stop/slow further damage. Here, we present a brief summary of various past and present treatment modalities to address the complications associated with RA.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Corticosteroides/efeitos adversos , Corticosteroides/uso terapêutico , Analgésicos Opioides/uso terapêutico , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Antirreumáticos/efeitos adversos , Antirreumáticos/uso terapêutico , Artrite Reumatoide/complicações , Artrite Reumatoide/cirurgia , Humanos , Imunossupressores/uso terapêutico , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Leflunomida/uso terapêutico , Modalidades de Fisioterapia , Fatores de Risco , Fator de Necrose Tumoral alfa/uso terapêutico
17.
J Cardiovasc Electrophysiol ; 27(4): 453-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26643285

RESUMO

INTRODUCTION: The safety of ventricular tachycardia (VT) ablation in patients with laminated left ventricular (LV) thrombus has not been examined. METHODS: Patients with laminated LV thrombus on transthoracic echocardiogram who underwent scar-mediated VT ablation at two centers from 2010 to 2013 were retrospectively analyzed. All patients had failed medical therapy. Acute procedural outcomes, complications, and clinical outcomes at 1 year were assessed. RESULTS: Eight patients (four ischemic, four nonischemic cardiomyopathy) underwent VT ablation in the presence of laminated intracavitary thrombus. Six out of eight (75%) had electrical storm (ES). The mapping and ablation approach was LV endocardial-only in three patients, epicardial-only in two, combined epicardial-RV endocardial in two, and combined epicardial-LV endocardial in one. Major complication (ischemic stroke) occurred in one patient 9 days post-procedure. There was no procedural mortality. Complete acute procedural success (noninducibility of any VT after ablation) was achieved in five (63%), and partial success (ablation of only clinical VT) in an additional three (37%). At 1 year, freedom from VT and survival were achieved in six (75%) and seven (88%) patients, respectively. CONCLUSION: Initial data suggest that ablation of VT in the presence of intracavitary thrombus is feasible, is associated with a similar success rate to historical studies in patients without thrombus, and has an acceptable risk of complications given the high-risk nature of patients with ES. Further data are needed; however, the presence of a laminated thrombus should not necessarily preclude ablation in patients who have failed medical therapy for VT in whom ablation is otherwise indicated.


Assuntos
Ablação por Cateter/mortalidade , Complicações Pós-Operatórias/mortalidade , Taquicardia Ventricular/mortalidade , Taquicardia Ventricular/cirurgia , Trombose/mortalidade , Trombose/cirurgia , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/prevenção & controle , Prevalência , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Taquicardia Ventricular/diagnóstico , Trombose/diagnóstico , Resultado do Tratamento , Estados Unidos/epidemiologia , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/mortalidade , Disfunção Ventricular Esquerda/cirurgia
18.
Eur Heart J ; 36(7): 440-8, 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25112662

RESUMO

AIMS: Previous studies on biventricular (BIV) pacing and cardiac resynchronization therapy-defibrillator (CRT-D) efficacy have used arbitrarily chosen BIV pacing percentages, and no study has employed implantable cardioverter defibrillator (ICD) patients as a control group. METHODS AND RESULTS: Using Kaplan-Meier plots, we estimated the threshold of BIV pacing percentage needed for CRT-D to be superior to ICD on the end-point of heart failure (HF) or death in 1219 left bundle branch block (LBBB) patients in the MADIT-CRT trial. Patients were censored at the time of crossover. In multivariable Cox analyses, no difference was seen in the risk of HF/death between ICD and CRT-D patients with BIV pacing ≤90% [HR = 0.78 (0.47-1.30), P = 0.344], and with increasing BIV pacing the risk of HF/death was decreased [CRT-D BIV 91-96% vs. ICD: HR = 0.63 (0.42-0.94), P = 0.024 and CRT-D BIV ≥97% vs. ICD: HR = 0.32 (0.23-0.44), P < 0.001]. The risk of death alone was reduced by 52% in CRT-D patients with BIV ≥97% (HR = 0.48, P < 0.016), when compared with ICD patients. Within the CRT-D group, for every 1 percentage point increase in BIV pacing, the risk of HF/death and death alone significantly decreased by 6 and 10%, respectively. Increasing BIV pacing percentage was associated with significant reductions in left ventricular volume. CONCLUSION: In patients with LBBB, who were in sinus rhythm at enrolment, BIV pacing exceeding 90% was associated with a benefit of CRT-D in HF/death when compared with ICD patients. Furthermore, BIV pacing ≥97% was associated with an even further reduction in HF/death, a significant 52% reduction in death alone, and increased reverse remodelling. Clinical trials.gov identifier: NCT00180271.


Assuntos
Bloqueio de Ramo/terapia , Terapia de Ressincronização Cardíaca/métodos , Desfibriladores Implantáveis , Insuficiência Cardíaca/terapia , Idoso , Bloqueio de Ramo/mortalidade , Terapia de Ressincronização Cardíaca/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Remodelação Ventricular/fisiologia
19.
PLoS Pathog ; 9(10): e1003658, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24130482

RESUMO

The role of Type I interferon (IFN) during pathogenic HIV and SIV infections remains unclear, with conflicting observations suggesting protective versus immunopathological effects. We therefore examined the effect of IFNα/ß on T cell death and viremia in HIV infection. Ex vivo analysis of eight pro- and anti-apoptotic molecules in chronic HIV-1 infection revealed that pro-apoptotic Bak was increased in CD4+ T cells and correlated directly with sensitivity to CD95/Fas-mediated apoptosis and inversely with CD4+ T cell counts. Apoptosis sensitivity and Bak expression were primarily increased in effector memory T cells. Knockdown of Bak by RNA interference inhibited CD95/Fas-induced death of T cells from HIV-1-infected individuals. In HIV-1-infected patients, IFNα-stimulated gene expression correlated positively with ex vivo T cell Bak levels, CD95/Fas-mediated apoptosis and viremia and negatively with CD4+ T cell counts. In vitro IFNα/ß stimulation enhanced Bak expression, CD95/Fas expression and CD95/Fas-mediated apoptosis in healthy donor T cells and induced death of HIV-specific CD8+ T cells from HIV-1-infected patients. HIV-1 in vitro sensitized T cells to CD95/Fas-induced apoptosis and this was Toll-like receptor (TLR)7/9- and Type I IFN-dependent. This sensitization by HIV-1 was due to an indirect effect on T cells, as it occurred in peripheral blood mononuclear cell cultures but not purified CD4+ T cells. Finally, peak IFNα levels and viral loads correlated negatively during acute SIV infection suggesting a potential antiviral effect, but positively during chronic SIV infection indicating that either the virus drives IFNα production or IFNα may facilitate loss of viral control. The above findings indicate stage-specific opposing effects of Type I IFNs during HIV-1 infection and suggest a novel mechanism by which these cytokines contribute to T cell depletion, dysregulation of cellular immunity and disease progression.


Assuntos
Apoptose/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Interferon-alfa/imunologia , Interferon beta/imunologia , Regulação para Cima/imunologia , Proteína Killer-Antagonista Homóloga a bcl-2/imunologia , Adolescente , Adulto , Animais , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Criança , Pré-Escolar , Feminino , Infecções por HIV/metabolismo , Infecções por HIV/patologia , HIV-1/metabolismo , Humanos , Imunidade Celular , Lactente , Interferon-alfa/metabolismo , Interferon beta/metabolismo , Macaca mulatta , Masculino , Receptor 7 Toll-Like/imunologia , Receptor 7 Toll-Like/metabolismo , Receptor Toll-Like 9/imunologia , Receptor Toll-Like 9/metabolismo , Carga Viral/imunologia , Viremia/imunologia , Viremia/metabolismo , Proteína Killer-Antagonista Homóloga a bcl-2/biossíntese , Receptor fas/imunologia , Receptor fas/metabolismo
20.
J Biomed Inform ; 53: 81-92, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25240252

RESUMO

Patient monitors in modern hospitals have become ubiquitous but they generate an excessive number of false alarms causing alarm fatigue. Our previous work showed that combinations of frequently co-occurring monitor alarms, called SuperAlarm patterns, were capable of predicting in-hospital code blue events at a lower alarm frequency. In the present study, we extend the conceptual domain of a SuperAlarm to incorporate laboratory test results along with monitor alarms so as to build an integrated data set to mine SuperAlarm patterns. We propose two approaches to integrate monitor alarms with laboratory test results and use a maximal frequent itemsets mining algorithm to find SuperAlarm patterns. Under an acceptable false positive rate FPRmax, optimal parameters including the minimum support threshold and the length of time window for the algorithm to find the combinations of monitor alarms and laboratory test results are determined based on a 10-fold cross-validation set. SuperAlarm candidates are generated under these optimal parameters. The final SuperAlarm patterns are obtained by further removing the candidates with false positive rate>FPRmax. The performance of SuperAlarm patterns are assessed using an independent test data set. First, we calculate the sensitivity with respect to prediction window and the sensitivity with respect to lead time. Second, we calculate the false SuperAlarm ratio (ratio of the hourly number of SuperAlarm triggers for control patients to that of the monitor alarms, or that of regular monitor alarms plus laboratory test results if the SuperAlarm patterns contain laboratory test results) and the work-up to detection ratio, WDR (ratio of the number of patients triggering any SuperAlarm patterns to that of code blue patients triggering any SuperAlarm patterns). The experiment results demonstrate that when varying FPRmax between 0.02 and 0.15, the SuperAlarm patterns composed of monitor alarms along with the last two laboratory test results are triggered at least once for [56.7-93.3%] of code blue patients within an 1-h prediction window before code blue events and for [43.3-90.0%] of code blue patients at least 1-h ahead of code blue events. However, the hourly number of these SuperAlarm patterns occurring in control patients is only [2.0-14.8%] of that of regular monitor alarms with WDR varying between 2.1 and 6.5 in a 12-h window. For a given FPRmax threshold, the SuperAlarm set generated from the integrated data set has higher sensitivity and lower WDR than the SuperAlarm set generated from the regular monitor alarm data set. In addition, the McNemar's test also shows that the performance of the SuperAlarm set from the integrated data set is significantly different from that of the SuperAlarm set from the regular monitor alarm data set. We therefore conclude that the SuperAlarm patterns generated from the integrated data set are better at predicting code blue events.


Assuntos
Alarmes Clínicos , Coleta de Dados , Processamento Eletrônico de Dados , Adulto , Idoso , Algoritmos , California , Simulação por Computador , Sistemas Computacionais , Cuidados Críticos/métodos , Mineração de Dados , Reações Falso-Positivas , Feminino , Parada Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas On-Line , Distribuição de Poisson , Curva ROC , Insuficiência Respiratória/diagnóstico
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