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1.
Multimed Tools Appl ; : 1-24, 2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-37362742

RESUMO

Sentiment Analysis is a highly crucial subfield in Natural Language Processing that attempts to extract the public sentiment from the accessible user opinions. This paper proposes a hybridized neural network based sentiment analysis framework using a modified term frequency-inverse document frequency approach. After preprocessing of data, the basic term frequency-inverse document frequency scheme is improved by introducing a non-linear global weighting factor. This improved scheme is combined with the k-best selection method to vectorize textual features. Next, the pre-trained embedding technique is employed for the mathematical representation of the textual features to process them efficiently by the Deep Learning methodologies. The embedded features are then passed to the deep neural network, consisting of Convolutional Neural Network and Long Short Term Memory. Convolutional Neural Networks can build hierarchical representations for capturing locally embedded features within the feature space, and Long Short Term Memory tries to recall useful historical information for sentiment polarization. This deep neural network finally provides the sentiment label. The proposed model is compared with different state-of-the-art baseline models in terms of various performance metrics using several datasets to demonstrate its efficacy.

2.
New Gener Comput ; 41(1): 25-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36439303

RESUMO

Early and fast detection of disease is essential for the fight against COVID-19 pandemic. Researchers have focused on developing robust and cost-effective detection methods using Deep learning based chest X-Ray image processing. However, such prediction models are often not well suited to address the challenge of highly imabalanced datasets. The current work is an attempt to address the issue by utilizing unsupervised Variational Auto Encoders (VAEs). Firstly, chest X-Ray images are converted to a latent space by learning the most important features using VAEs. Secondly, a wide range of well established data resampling techniques are used to balance the preexisting imbalanced classes in the latent vector form of the dataset. Finally, the modified dataset in the new feature space is used to train well known classification models to classify chest X-Ray images into three different classes viz., "COVID-19", "Pneumonia", and "Normal". In order to capture the quality of resampling methods, 10-folds cross validation technique is applied on the dataset. Extensive experimental analysis have been carried out and results so obtained indicate significant improvement in COVID-19 detection using the proposed VAE based method. Furthermore, the ingenuity of the results have been established by performing Wilcoxon rank test with 95% level of significance.

3.
IEEE Trans Fuzzy Syst ; 30(8): 2902-2914, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36345371

RESUMO

A global pandemic scenario is witnessed worldwide owing to the menace of the rapid outbreak of the deadly COVID-19 virus. To save mankind from this apocalyptic onslaught, it is essential to curb the fast spreading of this dreadful virus. Moreover, the absence of specialized drugs has made the scenario even more badly and thus an early-stage adoption of necessary precautionary measures would provide requisite supportive treatment for its prevention. The prime objective of this article is to use radiological images as a tool to help in early diagnosis. The interval type 2 fuzzy clustering is blended with the concept of superpixels, and metaheuristics to efficiently segment the radiological images. Despite noise sensitivity of watershed-based approach, it is adopted for superpixel computation owing to its simplicity where the noise problem is handled by the important edge information of the gradient image is preserved with the help of morphological opening and closing based reconstruction operations. The traditional objective function of the fuzzy c-means clustering algorithm is modified to incorporate the spatial information from the neighboring superpixel-based local window. The computational overhead associated with the processing of a huge amount of spatial information is reduced by incorporating the concept of superpixels and the optimal clusters are determined by a modified version of the flower pollination algorithm. Although the proposed approach performs well but should not be considered as an alternative to gold standard detection tests of COVID-19. Experimental results are found to be promising enough to deploy this approach for real-life applications.

4.
RSC Adv ; 12(8): 4605-4614, 2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35425513

RESUMO

An economically efficient and environmentally benign approach for the direct oxidative transformation of aldehydes to nitriles has been developed using commercially available non-toxic copper acetate as an inexpensive catalyst and ammonium acetate as the source of nitrogen in the presence of aerial oxygen as an eco-friendly oxidant under ligand-free conditions. The reactions were associated with high yield and various sensitive moieties like allyloxy, benzyloxy, t-butyldimethylsilyloxy, hetero-aryl, formyl, keto, chloro, bromo, methylenedioxy and cyano were well tolerated in the aforesaid method. The kinetic studies showed first order dependency on the aldehyde substrate in the reaction rate. The reaction was faster with the electron deficient aldehydes as confirmed by Hammett analysis. Moreover, the present oxidative method was effective on larger scales showing potential for industrial application.

5.
Vet Res Commun ; 46(3): 757-767, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35107723

RESUMO

Probiotics have emerged as biotherapeutic adjuncts to combat neonatal calf gastrointestinal disorders. Therefore, they are considered a suitable alternative to antibiotics for maintaining a healthy and balanced gut microbiota. Hence, the current investigation was carried out to evaluate the effect of autochthonous probiotics on Murrah buffalo calves. Sixteen calves (5-7 days of age) were randomly divided into four groups. Group I served as control (CT), fed a basal diet with no supplementation. Groups II (LR), III (LS), and IV (CS) were supplemented with Limosilactobacillus reuteri BF-E7, Ligilactobacillus salivarius BF-17, and a consortium of both probiotic strains at a rate of 1x108 CFU/g/calf per day along with the basal diet, respectively. Two previously isolated potential probiotic strains, Limosilactobacillus reuteri BF-E7 and Ligilactobacillus salivarius BF-17, were found to be compatible in vitro. Dietary supplementation of probiotics for sixty days significantly increased (P<0.05) dry matter intake (DMI, g/d), average daily gain (ADG, g/d), net body weight gain (kg), feed conversion efficiency (FCE), and structural growth measurements as compared to control. Furthermore, a considerable (P<0.05) increase in the abundance of beneficial intestinal microbiota (lactobacilli and bifidobacteria) was observed along with improvement in fecal biomarkers like lactate and ammonia, immune status, and reduced fecal score. Upon comparative analysis among treatment groups, the results were found to be better in the probiotic consortium fed group compared to the LR and LS treated groups. The present findings conclusively deduced that autochthonous probiotic consortium might serve as potential candidate for fostering performance, immunity, and gut health biomarkers in Murrah buffalo calves.


Assuntos
Búfalos , Probióticos , Ração Animal/análise , Animais , Biomarcadores , Dieta/veterinária , Lactobacillaceae , Probióticos/farmacologia
6.
Zoo Biol ; 41(4): 328-339, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35014724

RESUMO

Indian leopards kept in zoos are fed solely on carabeef on bone (CBB) diets. Carabeef contains lesser or no carotenoids. Hence, the captive Indian leopard diets are suspected to be deficient in carotenoids while their wild counterparts acquire these pigments from their natural prey. Lutein is a vital carotenoid that plays its role as an antioxidant and immunomodulator. This experiment investigates the effect of lutein supplementation on antioxidant status, immunity, and stress in captive Panthera fusca fed CBB diets. Nine leopards were used based on 3 × 3 replicated Latin square designs in the experiment. Groups CON, LUT20, and LUT40 were supplemented with 0, 20, and 40 ppm of lutein, respectively. Each experiment comprised of 10 days of wash-out period, 11 days of adaptation, and 4 days of collection. Digestibility of crude protein (CP) was higher (p < .01) in groups LUT20 and LUT40. Serum concentration of protein, globulin, urea (p < .05), total carotenoids, total antioxidant capacity (TAC), catalase (CAT) activity, and lymphocyte transformation test (LTT) index were higher (p < .001) in groups LUT20 and LUT40. Activity of superoxide dismutase (SOD) and serum concentration of immunoglobulin were higher (p < .001) in group LUT20. Serum concentration of malonaldehyde (MDA) and fecal concentration of cortisol decreased (p < .001) in groups LUT20 and LUT40. Serum concentration of total immunoglobulin (µg/ml) and LTT were higher in group LUT20. Fecal concentration of cortisol (ng/g) was lower in LUT20 and LUT40. The study concludes that supplementation of lutein at 20 ppm would improve antioxidant status and immunity and alleviate stress in captive Indian leopards.


Assuntos
Panthera , Animais , Animais de Zoológico , Antioxidantes , Carotenoides , Dieta/veterinária , Suplementos Nutricionais , Hidrocortisona , Luteína
7.
J Arrhythm ; 37(5): 1139-1147, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34621412

RESUMO

BACKGROUND: Left bundle branch (LBB) area pacing emerged as a promising alternative to His bundle (HB) pacing in difficult cases of physiological pacing and failed cases of cardiac resynchronization. So, it is important to understand ECG features of LBB area pacing in various subsets of patients. OBJECTIVE: We wanted to find out different morphological patterns and characteristic ECG features of LBB area pacing. METHOD: Medtronic 3830 pacing lead was used to pierce the interventricular septum 1-2 cm distal towards the RV cavity to a previously placed electrophysiology catheter at distal HB region to reach the LBB area in the right anterior oblique (RAO) 30 degree projection. We observed paced QRS morphology in lead V1 and paced QRS duration. RESULTS: We have analyzed ECG features of 60 patients who had undergone LBB area pacing and 60 patients with RV apical pacing. LBB area pacing resulted in narrower-paced QRS complex than conventional RV apical pacing. In patients with baseline LBBB QRS shortening from LBB area pacing was more in comparison to patients with RBBB (34.45 ± 8.07 ms vs 19.78 ± 10.24 ms, P value .004). Paced QRS morphological pattern in lead V1 was most commonly qR pattern followed by Qr pattern. CONCLUSIONS: LBB area pacing results in narrower-paced QRS duration than RV apical pacing. The morphological pattern is most commonly a qR or Qr pattern in lead V1. Patients with baseline RBBB showed lesser paced QRS shortening in comparison to patients with baseline LBBB.

8.
Trop Anim Health Prod ; 53(2): 291, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33909188

RESUMO

The objective of this study was to evaluate the effects of synbiotic formulation of Cichorium intybus root powder (C) with Lactobacillus acidophilus NCDC15 (LA) and Lactobacillus reuteri BFE7 (LR) on growth performance in Murrah buffalo calves via monitoring selective gut health indices. Twenty-four Murrah buffalo calves of 5-7 days old and 33 ± 2.0 kg of body weight were distributed randomly into three groups adopting complete randomized design (CRD) as follows: (1) group I served as control (CON) provided with a basal diet alone; (2) group II supplemented with synbiotic formulation of 200 mL L. acidophilus NCDC15 fermented milk with 8 g of Cichorium intybus root powder (LAC) along with basal diet; (3) group III supplemented with synbiotic formulation of 200 mL L. reuteri BFE7 fermented milk with 8 g of Cichorium intybus root powder (LRC) along with basal diet. The final body weight (BW), average dry matter intake (DMI) and structural body measurements were significantly increased (P < 0.05) in LAC and LRC groups by synbiotic as compared to the CON. No effect was registered on apparent nutrient digestibility coefficient of various nutrients in supplemented groups. Faecal score was reduced by the supplementation of synbiotic being lowest in LRC followed by LAC and CON. Calves supplemented synbiotic showed lower (P < 0.05) faecal pH and ammonia with a concomitant increase in faecal lactate levels and faecal short chain fatty acids (SCFA) as compared to control. The faecal Lactobacillus and Bifidobacterium population was increased (P < 0.05) in synbiotic fed groups as compared to control. Additionally, coliform and clostridia count was decreased (P < 0.05) in treatment groups compared to CON. Overall, it may be concluded that synbiotic supplementation was effective in improving the growth performance in Murrah buffalo calves via altering selective gut health indices.


Assuntos
Cichorium intybus , Limosilactobacillus reuteri , Simbióticos , Ração Animal/análise , Animais , Búfalos , Dieta/veterinária , Lactobacillus acidophilus , Pós
9.
Interdiscip Sci ; 13(2): 229-259, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33576956

RESUMO

The amount of information in the scientific literature of the bio-medical domain is growing exponentially, which makes it difficult in developing a smart medical system. Summarization techniques help for efficient searching and understanding of relevant information from the medical documents. In the paper, an evolutionary algorithm based ensemble extractive summarization technique is devised as a smart medical application with the idea of hybrid artificial intelligence on natural language processing. We have considered the abstracts of the target article and its cited articles as the base summaries and a multi-objective evolutionary algorithm is applied for generating the ensemble summary of the target article. Each sentence of the base summaries is represented by a concept vector of the medical terms contained in it with the help of the Unified Modelling Language System (UMLS) tool which is widely used in various smart medical applications. These terms carry the key information of the sentence which is very useful to find out the semantic similarity among the sentences. Fitness functions of the evolutionary algorithm are mainly defined using clustering coefficient and sparsity index, the concepts of graph theory. After the convergence of the algorithm, the best solution of the final population gives the ensemble summary. Next, the semantic similarity of each sentence in the target article with the ensemble summary is calculated and the sentences which are most similar to the ensemble summary are considered as the summary of the target article. The method is applied to the articles available in the PubMed MEDLINE database system and experimental results are compared with some state of the art methods applied in the Bio-medical domain. Experimental results and comparative study based on the performance evaluation show that the method competes with some recently proposed summarization methods and outperforms others, which express the effectiveness of the proposed methodology. Different statistical tests have also been made to observe that the method is statistically significant.


Assuntos
Inteligência Artificial , Processamento de Linguagem Natural , Análise por Conglomerados , Semântica
10.
J Anim Physiol Anim Nutr (Berl) ; 105(2): 406-417, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33258509

RESUMO

This experiment was conducted to study nutrient and mineral utilization in greater one-horned rhinoceros fed season-specific diets. Nine adult greater one-horned rhinoceros (774-2407 kg BW) of Sanjay Gandhi Biological Park, Patna, Bihar, India, were used in this experiment. Three digestion trials of 60-d duration were conducted per animal, out of which 55 days was adaptation period and 5 days was collection period. The amount of concentrate was kept constant during all the trials. Green fodder sources were sugarcane, berseem (Trifolium alexndrinum) and chari (Sorghum bicolor) during trials I, II and III respectively. Green fodders were offered 20% in excess of previous day's intake in the afternoon. Apparent digestibility of dry matter and crude fibre was higher (p < .01) in group II as compared to other groups. Apparent digestibility of crude protein was lowest (p < .01) in group I, followed by group III, and the highest value was observed in group II. Apparent digestibility of Ca and P was lower in greater one-horned rhinoceros fed sugarcane and sorghum as green fodder source. In spite of this, sugarcane and sorghum-based diets were able to meet the requirement of Ca, P, Fe and Mn. Berseem supplied Ca in excess of requirement. All the diets were deficient in Zn. Hence, a suitable supplement of Zn should be added to the conventional zoo diet of greater one-horned rhinoceros.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Digestão , Ração Animal/análise , Animais , Dieta/veterinária , Minerais , Nutrientes , Perissodáctilos , Estações do Ano
11.
Heart Vessels ; 35(11): 1563-1572, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32458055

RESUMO

Chronic RV pacing may lead to pacing induced cardiomyopathy in some patients and results in a higher risk of development of LV systolic dysfunction, heart failure, mitral regurgitation and atrial fibrillation. His bundle pacing emerged as the most physiologic form of ventricular pacing. However, wide adoption of this technique in routine clinical practice is limited by higher capture thresholds at implant sometimes, lower R wave amplitudes, atrial over sensing and increased risk for late rise in pacing thresholds (resulting in the need for lead revisions). Some recent studies have focused on left bundle branch area pacing as a solution to these problems. In our study, we have compared left bundle branch area pacing (in 22 patients) with conventional right ventricular apical pacing (in 28 patients) who presented to us with conventional indications for pacemaker implantations in term of procedure and fluoroscopy time and short-term lead performance and left ventricular function. The results of our study showed that left bundle branch area pacing is associated with shortened QRS duration (22.36 ± 9.36 ms) and better LV function (higher left ventricular ejection fraction 64.00 ± 3.03 vs. 59.73 ± 6.73 with a p value of 0.013 and lower left ventricular diastolic internal diameter 4.58 ± 0.32 vs. 5.23 ± 0.40 cm with a p value of < 0.001) in comparison to right ventricular apical pacing. The total procedure time and fluoroscopy time was similar (63.15 ± 7.02 vs. 55.15 ± 6.16 min, p value 0.142 and 6.08 ± 1.42 vs. 5.06 ± 1.30 min, p value 0.332 respectively) in left bundle branch area pacing group. The results of this study indicate that left bundle branch area pacing may be an option for physiological pacing in patients requiring a high percentage of ventricular pacing.


Assuntos
Potenciais de Ação , Fascículo Atrioventricular/fisiopatologia , Estimulação Cardíaca Artificial/métodos , Bloqueio Cardíaco/terapia , Frequência Cardíaca , Idoso , Estimulação Cardíaca Artificial/efeitos adversos , Feminino , Bloqueio Cardíaco/diagnóstico , Bloqueio Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Volume Sistólico , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda , Função Ventricular Direita
12.
IEEE Trans Cybern ; 50(11): 4821-4834, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31265425

RESUMO

Differential evolution (DE) has established itself as a simple but efficient population-based, nonconvex optimization algorithm for continuous search spaces. Unlike the conventional real-coded genetic algorithms (GAs) and evolution strategies (ESs), DE uses a mandatory self-referential mutation for its population members, each of which are perturbed with the scaled difference(s) of the individuals from the current generation (iteration). These difference vectors determine the direction of the search moves for the individuals. However, unlike the better individuals, they are not retained in the elitist evolution cycle of DE. In this paper, we show that by archiving the most promising difference vectors from past generations and then by reusing them for generating offspring in the subsequent generations, we can strikingly improve the performance of DE. This strategy can be integrated with any classical or advanced DE variant with no serious overhead in time or space complexity. We demonstrate that when combined with the DE-based winners of the IEEE Congress on Evolutionary Computation (CEC) 2013, 2014, and 2017 competitions on real parameter optimization, the simple reuse strategy leads to a statistically significant performance improvement in the majority of test cases. We further showcase the efficacy of our proposal on a practical optimization problem concerning the design of circular antenna arrays with a prespecified radiation pattern.

13.
Heart Vessels ; 34(9): 1552-1558, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30963301

RESUMO

Several studies have reported the adverse effects of right ventricular apical pacing. Permanent His bundle pacing is proved to be the most physiological. But it can be technically difficult sometimes. One recent large multicenter randomized trial showed that pacing from left ventricular apex or mid-lateral wall has the greatest potential to prevent pacing-induced reduction of cardiac pump function (by maintaining left ventricular mechanical synchrony) and, therefore, can be considered as physiological site. In our study, we have wanted to see the outcome of left ventricular pacing through coronary sinus branch with active fixation bipolar lead as a routine pacing technique in patients with symptomatic left bundle branch block. In our study we have recruited 27 patients for left ventricular pacing through coronary sinus branch (as done in cardiac resynchronization therapy) with active fixation bipolar lead and 33 patients for right ventricular apical pacing (control) and compared left ventricular pacing with right ventricular apical pacing in patients with history of syncope with left bundle branch block in baseline electrocardiography who presented with atrio-ventricular block or prolonged HV interval (≥ 70 ms) on electrophysiology study in term of procedure and fluoroscopy time and short-term lead performance and left ventricular function. The results of our study showed that left ventricular pacing through a tributary of coronary sinus is associated with shortened QRS duration (21.10 ± 3.92 ms) and better LV function (higher left ventricular ejection fraction 64.00 ± 3.03 vs. 59.73 ± 6.73 and lower left ventricular diastolic internal diameter 4.58 ± 0.32 vs. 5.23 ± 0.40 cm) in comparison to right ventricular apical pacing. However, the total procedure time and fluoroscopy time was significantly higher (73.75 ± 11.02 vs. 63.32 ± 6.06 min and 7.08 ± 1.48 vs. 5.02 ± 1.39 min, respectively) in left ventricular pacing group. The results of this study indicate that transvenous left ventricular epicardial pacing may be an option for physiological pacing in patients with symptomatic left bundle branch block.


Assuntos
Fascículo Atrioventricular/fisiopatologia , Bloqueio de Ramo/terapia , Estimulação Cardíaca Artificial/métodos , Ventrículos do Coração/fisiopatologia , Função Ventricular Esquerda/fisiologia , Idoso , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/fisiopatologia , Cateterismo Cardíaco , Ecocardiografia , Eletrocardiografia , Estudos de Viabilidade , Feminino , Fluoroscopia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
14.
Zoo Biol ; 38(3): 292-304, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30955226

RESUMO

This experiment was conducted to study the effect of gradual replacement of dietary buffalo meat on the bone (BMB) with chicken carcass (CC) on nutrient utilization, serum cortisol, and total serum antioxidant profile of zoo-housed Indian leopard. Twelve adult leopards were randomly distributed into a replicated Latin square design comprising three treatments, three periods, four animals, and three sequences. Leopards in group T1 were fed normal zoo diet of BMB. On the basis of dry matter, 10% and 20% of BMB was replaced with CC in groups T2 and T3 , respectively. Each experimental period comprised 21 days. During each period, a digestion trial of 4-day collection period was conducted after an adaptation period of 17 days. On Day 21 of each experimental period, blood was collected from all the animals by puncturing the ventral coccygial vein. Intake and apparent digestibility of major nutrients were similar among the groups. Replacement of 20% BMB with addition of CC increased (p < 0.001) the calculated supply of I, niacin, and vitamin A. Carotenoid intake increased (p < 0.01) with increased level of CC in the diet. Serum concentration of cortisol decreased (p < 0.01) whereas serum concentration of total carotenoids increased (p < 0.001) with increased level of CC in the diet. Serum concentration of antioxidant enzymes increased (p < 0.001) with increased level of CC in the diet. It was concluded that replacement of 20% of BMB with CC increased antioxidant profile. This may reduce oxidative stress in zoo-housed Indian leopards without any adverse effect on nutrient utilization.


Assuntos
Antioxidantes/análise , Dieta/veterinária , Panthera/sangue , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais de Zoológico/sangue , Búfalos , Carotenoides/sangue , Galinhas , Hidrocortisona/sangue , Índia , Panthera/fisiologia , Distribuição Aleatória
15.
Indian Heart J ; 70(5): 713-720, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30392512

RESUMO

Adverse hemodynamics of right ventricular (RV) pacing is known for years. Several studies have revealed that adverse outcomes of RV apical pacing are directly linked to cumulative percentage of ventricular pacing. Algorithms to minimize ventricular pacing are only effective if there is good atrioventricular (AV) conduction. A need for an alternate site for ventricular pacing is evident in patients with high presumed ventricular pacing burden. Most studied alternate site for ventricular pacing is ventricular septum (outflow tract septum and mid-septum). Conventionally septal position of the ventricular pacing lead is confirmed by fluoroscopic appearance of the lead and characteristics electrocardiographic (ECG) features. However, several recent studies have challenged these fluoroscopic and ECG features as to be inadequate. So, there is need for a systematic approach for septal positioning of the ventricular lead.


Assuntos
Algoritmos , Arritmias Cardíacas/terapia , Estimulação Cardíaca Artificial/métodos , Eletrocardiografia , Eletrodos Implantados , Sistema de Condução Cardíaco/fisiopatologia , Septo Interventricular , Arritmias Cardíacas/fisiopatologia , Humanos
16.
Indian Heart J ; 69(6): 725-730, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29174249

RESUMO

BACKGROUND: Sinus node disease is associated with widespread structural and electrophysiological changes in the atria in addition to abnormalities at the sinus node. The atrial conduction disorder in patients with atrial pacing results in higher incidence of atrial fibrillation. Studies have shown that low interatrial septal pacing is superior to right atrial appendage pacing in preventing persistent or permanent atrial fibrillation in these patients. However, implantation of active fixation lead in low interatrial septal position is difficult and time consuming with conventional stylet, inhibiting application of this method in routine practice. METHOD: The technique of implanting atrial pacing lead in low interatrial septum with hand-made stylet is presented in this study with emphasis on fluoroscopic landmark and electrocardiographic P wave pattern. RESULTS: The results indicate acute and short-term success of low interatrial septal pacing in 10 patients out of 11 patients without major complications. Pacing parameters during implantation and 3 months post procedure were within normal limits. CONCLUSION: The initial favorable results of this study indicate low interatrial septal pacing with conventional active fixation lead using fluoroscopic landmark and electrocardiographic characteristics is feasible and reproducible with a simple technique.


Assuntos
Fibrilação Atrial/terapia , Septo Interatrial/fisiopatologia , Estimulação Cardíaca Artificial/métodos , Sistema de Condução Cardíaco/fisiopatologia , Idoso , Fibrilação Atrial/fisiopatologia , Septo Interatrial/diagnóstico por imagem , Eletrocardiografia , Feminino , Fluoroscopia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
17.
Indian Heart J ; 69(5): 675-680, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29054201

RESUMO

Atrial pacing is done for either symptomatic sinus node dysfunction (SND) or for maintenance of atrio-ventricular synchrony in a dual chamber pacemaker. Conventionally, atrial lead is placed in the right atrial appendage. Atrial conduction disorder in patients with permanent pacing results in higher incidence of atrial fibrillation. Atrial septal pacing has emerged as a solution to this problem. So, it is extremely important to understand the different features of paced P wave from various atrial pacing sites. Conventional right atrial appendage pacing in presence of atrial conduction disorder results in marked latency with prolonged P wave duration with reduced amplitude. The morphology is similar to sinus rhythm. Atrial septal pacing causes short and sharp P wave with negative polarity in inferior leads and positive polarity in lead V1 in lower septal pacing, whereas positive polarity in inferior leads and negative polarity in lead V1 during pacing from upper septum.


Assuntos
Fibrilação Atrial/terapia , Estimulação Cardíaca Artificial/métodos , Eletrocardiografia , Átrios do Coração/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Fibrilação Atrial/fisiopatologia , Humanos
18.
Indian Heart J ; 68(5): 678-684, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27773407

RESUMO

BACKGROUND: Pacing in the Bachmann's bundle (BB) area (upper atrial septum) appears superior to right atrial appendage or free wall stimulation for the prevention of paroxysmal atrial fibrillation in patients with atrial conduction delay. However, insertion of active fixation lead in the upper atrial septal position is difficult and time consuming with conventional stylet, inhibiting application of this pacing method in routine practice. METHODS: The technique of positioning the atrial lead in BB with hand-made stylet is presented with emphasis on electrocardiographic P-wave pattern and fluoroscopic landmarks. RESULTS: The results demonstrate an acute implantation and short-term success of BB pacing of 14 patients out of 15 patients without major complications. Pacing parameters at implantation and 3 months postprocedure were noted which were within normal limits. CONCLUSION: These favorable initial results indicate that the positioning of active fixation atrial lead in BB with fluoroscopic landmarks is feasible and reproducible with a simple technique.


Assuntos
Apêndice Atrial/fisiopatologia , Fibrilação Atrial/terapia , Estimulação Cardíaca Artificial/métodos , Eletrodos Implantados , Sistema de Condução Cardíaco/fisiopatologia , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Eletrocardiografia , Desenho de Equipamento , Feminino , Fluoroscopia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
19.
Zoo Biol ; 35(6): 522-532, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27623542

RESUMO

This experiment was conducted to evaluate the effects of feeding different levels of green forages on feed consumption, nutrient and mineral utilization in Golden pheasants (GP). Twenty-seven female GP (BW 617-635 g) were randomly distributed into three groups of nine birds each in an experiment based on completely randomized design (CRD). Birds in group T1 were fed a conventional zoo diet containing 1.4% green forages; however, the diets of the birds in groups T2 and T3 contained 2.7% and 5.0% of green forages, respectively. Intake of total carotenoids increased with increased level of green forages in the diet. Apparent retention of N, Ca, and Zn was higher in GP laying hens fed diet containing 5.0% green forages as compared to those fed conventional diet containing 1.4% green forages. Results of the present study indicate that inclusion of 5% green forage in the diet of GP would improve the utilization of N, Ca, and Zn without any adverse effect on intake and utilization of other nutrients. Data related to nutrient intake, basal endogenous losses (BEL) and coefficient of retention (COR) of N, Ca, P, Mg, Fe, Cu, Mn, and Zn are novel and may be of use for future research. Zoo Biol. 35:522-532, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Animais de Zoológico/fisiologia , Carotenoides/metabolismo , Suplementos Nutricionais , Galliformes/fisiologia , Minerais/metabolismo , Nitrogênio/metabolismo , Ração Animal/normas , Animais , Dieta/veterinária , Feminino , Galliformes/metabolismo , Distribuição Aleatória
20.
Indian Heart J ; 68(4): 552-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27543481

RESUMO

Adverse hemodynamics of right ventricular (RV) pacing is a well-known fact. It was believed to be the result of atrio-ventricular (AV) dyssynchrony and sequential pacing of the atrium and ventricle may solve these problems. However, despite maintenance of AV synchrony, the dual chamber pacemakers in different trials have failed to show its superiority over single chamber RV apical pacing in terms of death, progression of heart failure, and atrial fibrillation (AF). As a consequence, investigators searched for alternate pacing sites with a more physiological activation pattern and better hemodynamics. Direct His bundle pacing and Para-Hisian pacing are the most physiological ventricular pacing sites. But, this is technically difficult. Ventricular septal pacing compared to apical pacing results in a shorter electrical activation delay and consequently less mechanical dyssynchrony. But, the study results are heterogeneous. Selective site atria pacing (atrial septal) is useful for patients with atrial conduction disorders in prevention of AF.


Assuntos
Fibrilação Atrial/terapia , Fascículo Atrioventricular/fisiopatologia , Estimulação Cardíaca Artificial/métodos , Hemodinâmica , Fibrilação Atrial/fisiopatologia , Eletrocardiografia , Humanos
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