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1.
Funct Integr Genomics ; 23(4): 302, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37721631

RESUMO

Women's most frequent type of cancer is breast cancer, second only to lung cancer. This paper summarizes changes in genomics and epigenetics and incremental biological activities. A tumour develops through a series of phases involving a separate abnormal gene. Even though many diseases cause DNA mutations, most treatments are designed to relieve symptoms rather than change the DNA. Clustering short palindromic repeats (CRISPR) or Cas9 is the primary approach for discovering and confirming tumorigenic genomic targets. A Kohonen neural network with an expression programming model was developed for gene selection. The main problem in genetic selection is reducing the number of features chosen while maintaining accuracy. This purpose is accomplished systematically. In the end, the approach method performed better than the existing quantum squirrel-inspired algorithm and the recurrent neural network oppositional call search algorithm for genetic selection. The KNNet-EPM model used an expression programming approach to identify gene biomarkers for breast cancer. This method was achieved with RAE of 42%, sensitivity of 93%, f1 score of 88%, accuracy of 98%, kappa score of 83%, specificity of 92% and MAE of 30%.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Feminino , Humanos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Inteligência Artificial , Algoritmos , Carcinogênese
2.
Nano Lett ; 11(3): 1014-9, 2011 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-21287999

RESUMO

We report a versatile all optical technique to excite and read-out a distributed nanoelectromechanical systems (NEMS) array. The NEMS array is driven by a distributed, intensity modulated optical pump through the photothermal effect. The ensuing vibrational response of the array is multiplexed onto a single probe beam in the form of a high frequency phase modulation. The phase modulation is optically down converted to a low frequency intensity modulation using an adaptive full-field interferometer, and subsequently detected using a CCD array. Rapid and single step mechanical characterization of ∼44 nominally identical high-frequency resonators is demonstrated. The technique may enable sensitivity improvements over single NEMS resonators by averaging signals coming from a multitude of devices in the array. In addition, the diffraction limited spatial resolution may allow for position-dependent read-out of NEMS sensor chips for sensing multiple analytes or spatially inhomogeneous forces.

3.
Comput Intell Neurosci ; 2022: 2898061, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35341197

RESUMO

In recent times, the Internet of Medical Things (IoMT) is a new loomed technology, which has been deliberated as a promising technology designed for various and broadly connected networks. In an intelligent healthcare system, the framework of IoMT observes the health circumstances of the patients dynamically and responds to backings their needs, which helps detect the symptoms of critical rare body conditions based on the data collected. Metaheuristic algorithms have proven effective, robust, and efficient in deciphering real-world optimization, clustering, forecasting, classification, and other engineering problems. The emergence of extraordinary, very large-scale data being generated from various sources such as the web, sensors, and social media has led the world to the era of big data. Big data poses a new contest to metaheuristic algorithms. So, this research work presents the metaheuristic optimization algorithm for big data analysis in the IoMT using gravitational search optimization algorithm (GSOA) and reflective belief network with convolutional neural networks (DBN-CNNs). Here the data optimization has been carried out using GSOA for the collected input data. The input data were collected for the diabetes prediction with cardiac risk prediction based on the damage in blood vessels and cardiac nerves. Collected data have been classified to predict abnormal and normal diabetes range, and based on this range, the risk for a cardiac attack has been predicted using SVM. The performance analysis is made to reveal that GSOA-DBN_CNN performs well in predicting diseases. The simulation results illustrate that the GSOA-DBN_CNN model used for prediction improves accuracy, precision, recall, F1-score, and PSNR.


Assuntos
Ciência de Dados , Mídias Sociais , Algoritmos , Simulação por Computador , Humanos , Redes Neurais de Computação
4.
J Acoust Soc Am ; 130(5): 3389-95, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22088012

RESUMO

An experimental setup for nucleating clouds of bubbles in a high-pressure spherical resonator is described. Using nanosecond laser pulses and multiple phase gratings, bubble clouds are optically nucleated in an acoustic field. Dynamics of the clouds are captured using a high-speed CCD camera. The images reveal cloud nucleation, growth, and collapse and the resulting emission of radially expanding shockwaves. These shockwaves are reflected at the interior surface of the resonator and then reconverge to the center of the resonator. As the shocks reconverge upon the center of the resonator, they renucleate and grow the bubble cloud. This process is repeated over many acoustic cycles and with each successive shock reconvergence, the bubble cloud becomes more organized and centralized so that subsequent collapses give rise to stronger, better defined shockwaves. After many acoustic cycles individual bubbles cannot be distinguished and the cloud is then referred to as a cluster. Sustainability of the process is ultimately limited by the detuning of the acoustic field inside the resonator. The nucleation parameter space is studied in terms of laser firing phase, laser energy, and acoustic power used.


Assuntos
Acústica/instrumentação , Efeito Doppler , Desenho de Equipamento , Gases , Lasers de Estado Sólido , Movimento (Física) , Fotografação , Pressão , Processamento de Sinais Assistido por Computador , Propriedades de Superfície , Fatores de Tempo , Vibração
5.
Science ; 350(6257): 198-203, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26450210

RESUMO

Cellulose biosynthesis in plant secondary cell walls forms the basis of vascular development in land plants, with xylem tissues constituting the vast majority of terrestrial biomass. We used plant lines that contained an inducible master transcription factor controlling xylem cell fate to quantitatively image fluorescently tagged cellulose synthase enzymes during cellulose deposition in living protoxylem cells. The formation of secondary cell wall thickenings was associated with a redistribution and enrichment of CESA7-containing cellulose synthase complexes (CSCs) into narrow membrane domains. The velocities of secondary cell wall-specific CSCs were faster than those of primary cell wall CSCs during abundant cellulose production. Dynamic intracellular of endomembranes, in combination with increased velocity and high density of CSCs, enables cellulose to be synthesized rapidly in secondary cell walls.


Assuntos
Proteínas de Arabidopsis/análise , Arabidopsis/enzimologia , Parede Celular/enzimologia , Glucosiltransferases/análise , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Proteínas de Bactérias/análise , Parede Celular/ultraestrutura , Celulose/biossíntese , Celulose/metabolismo , Fluorescência , Glucosiltransferases/química , Glucosiltransferases/metabolismo , Complexo de Golgi/enzimologia , Proteínas Luminescentes/análise , Microtúbulos/enzimologia , Transporte Proteico , Xilema/enzimologia , Xilema/crescimento & desenvolvimento
6.
J Thorac Cardiovasc Surg ; 104(5): 1264-7, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1434703

RESUMO

The hemodynamic response to closed mitral commissurotomy, single-balloon, and double-balloon mitral valvuloplasty was compared using 20 patients in each group. All patients had symptomatic rheumatic mitral stenosis with a mitral valve area < 1 cm2, without any left atrial clot, mitral valve calcification, or mitral regurgitation. There was a significant improvement in hemodynamics following intervention in all three groups. The mean pulmonary artery pressure decreased from 49.1 +/- 17.5 to 28.6 +/- 8.3 mm Hg (p < 0.001), 48.8 +/- 12.3 to 34.0 +/- 13.9 mm Hg (p < 0.001), and 46.7 +/- 18.0 to 26.3 +/- 13.7 mm Hg (p < 0.001) in the closed mitral commissurotomy, single-balloon, and double-balloon mitral valvuloplasty groups, respectively. The mitral valve area increased from 0.62 +/- 0.27 to 1.5 +/- 0.5 cm2 (p < 0.001), 0.68 +/- 0.24 to 1.5 +/- 0.4 cm2 (p < 0.001), and 0.68 +/- 0.25 to 1.9 +/- 0.8 cm2 (p < 0.001) in the closed mitral commissurotomy, single-balloon, and double-balloon mitral valvuloplasty groups, respectively. The increase in the mitral valve area was maximum in the group with double-balloon mitral valvuloplasty. In the closed mitral commissurotomy group there was a significant rise in left ventricular end-diastolic pressure, from 6.8 +/- 3.9 to 9.3 +/- 3.1 mm Hg (p < 0.001), but this remained unchanged in the single-balloon and double-balloon mitral valvuloplasty groups. Our study shows that single-balloon and double-balloon mitral valvuloplasty are comparable to closed mitral commissurotomy in the immediate hemodynamic response, with a larger valve area in the double-balloon mitral valvuloplasty group.


Assuntos
Cateterismo/métodos , Hemodinâmica , Estenose da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Cardiopatia Reumática/cirurgia , Adolescente , Adulto , Procedimentos Cirúrgicos Cardíacos/métodos , Criança , Feminino , Humanos , Masculino , Valva Mitral/patologia , Estenose da Valva Mitral/fisiopatologia , Período Pós-Operatório , Cardiopatia Reumática/fisiopatologia
7.
J Thorac Cardiovasc Surg ; 91(2): 168-73, 1986 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3945083

RESUMO

Fourteen patients underwent thrombectomy for thrombosis of implanted Björk-Shiley valves (13 in the mitral and one in the aortic position) between January, 1975, and July, 1984. There was no operative mortality or perioperative embolism. Over a follow-up period of 1 to 96 months (average 23.5 months), there was no late mortality. Serial evaluation of valve function by cinefluoroscopy and echocardiography has shown no evidence of rethrombosis or valve dysfunction in any of the patients. Cardiac catheterization and angiocardiography done in 10 patients at various intervals (1 month to 6 years) postoperatively have shown normal valve function in all and normalization of elevated preoperative intracardiac pressures in the majority. Our experience suggests that thrombectomy of thrombosed Björk-Shiley valves provides excellent early and long-term results in terms of patient survival and valve function.


Assuntos
Cardiopatias/cirurgia , Próteses Valvulares Cardíacas/efeitos adversos , Trombose/cirurgia , Adulto , Angiocardiografia , Valva Aórtica/fisiopatologia , Valva Aórtica/cirurgia , Cateterismo Cardíaco , Cinerradiografia , Ecocardiografia , Feminino , Seguimentos , Cardiopatias/etiologia , Cardiopatias/fisiopatologia , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/fisiopatologia , Valva Mitral/cirurgia , Desenho de Prótese , Trombose/etiologia , Trombose/fisiopatologia
8.
Ann Thorac Surg ; 31(1): 28-35, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7006534

RESUMO

Ninety patients, operated on from May, 1978, through June, 1979, underwent coronary endarterectomy and early recatheterization. Patency of grafts to endarterectomized arteries was 103 of 118 (87.3%) and patency of conventional vein grafts in the same patients was 217 of 233 (93.1%). Myocardial blood flow using xenon 133 washout, at rest and with isoproterenol-induced stress, was measured in 7 normal coronary arteries, 28 conventional saphenous vein grafts, and 33 saphenous vein grafts to endarterectomized coronary arteries. The increase in myocardial blood flow, from rest to isoproterenol-induced stress, was comparable for the three groups. The endarterectomized group was divided further by separating out the 10 patients with heavy scarring or residual disease. The remaining patients had a flow response identical to those with conventional saphenous vein grafts. The rate of perioperative infarction in patients receiving endarterectomy was 3 of 113 (2.6%), as measured by appearance of new persistent Q waves on the serial postoperative electrocardiogram. Positive pyrophosphate scans were noted in 12 of 105 (12.4%) patients. It is concluded that, in the early stages at least, grafts to endarterectomized coronary arteries stay open and perfuse the myocardium as well as conventional saphenous vein grafts unless the myocardium is heavily scarred or unless residual disease remains.


Assuntos
Arteriosclerose/cirurgia , Vasos Coronários/cirurgia , Endarterectomia , Revascularização Miocárdica/métodos , Circulação Coronária , Coração/diagnóstico por imagem , Coração/efeitos dos fármacos , Humanos , Isoproterenol/farmacologia , Técnica de Diluição de Radioisótopos , Cintilografia , Tecnécio , Radioisótopos de Xenônio
9.
Int J Cardiol ; 20(2): 279-82, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3209260

RESUMO

Massive mitral valvular and myocardial calcification is rare. Successful valve replacement poses a technical challenge. One such case is described with a 5-year follow-up.


Assuntos
Calcinose/cirurgia , Próteses Valvulares Cardíacas , Estenose da Valva Mitral/cirurgia , Adulto , Humanos , Masculino , Desenho de Prótese
10.
Int J Cardiol ; 23(1): 19-26, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2714910

RESUMO

Seventy-eight patients undergoing mitral valve surgery with or without replacement of the aortic valve also underwent procedures on the tricuspid valve over a period of 10 years. All patients were in functional class III or IV preoperatively. The procedures were performed in all patients with organic disease of the tricuspid valve (N = 44) and in those with moderate or severe functional tricuspid valvar regurgitation (N = 34). Seventy-one patients underwent DeVega's annuloplasty with or without commissurotomy. The overall mortality was 11.5%. 65 long-term survivors were followed up for a period of 6 months to 10 years (mean 5.3 years). Sixty-three patients were in functional class I or II at the last follow-up. Six patients had clinical evidence of mild to moderate tricuspid regurgitation. Regression of cardiomegaly (as judged by the chest radiograph and right ventricular hypertrophy seen in the electrocardiogram) was evident in most cases. Fifty-one of 54 patients evaluated by cross-sectional echocardiography were reported to have a functionally normal tricuspid valve. Doppler echocardiography in 28 patients showed no significant tricuspid regurgitation or stenosis in 26 patients. Eleven consecutive patients undergoing DeVega's annuloplasty were studied prospectively with pre- and postoperative Doppler echocardiography. Good correlation existed between right ventricular systolic pressures predicted by Doppler with those obtained preoperatively at cardiac catheterization. Postoperative Doppler echocardiography in these 11 patients showed complete restoration of competence of the tricuspid valve as well as normalisation of the right ventricular systolic pressure in 10 patients.


Assuntos
Doenças das Valvas Cardíacas/cirurgia , Valva Tricúspide/cirurgia , Adulto , Ecocardiografia , Ecocardiografia Doppler , Feminino , Doenças das Valvas Cardíacas/diagnóstico , Doenças das Valvas Cardíacas/mortalidade , Humanos , Estudos Longitudinais , Masculino , Valva Tricúspide/patologia
11.
Int J Cardiol ; 18(3): 317-25, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3360519

RESUMO

Eighteen patients underwent surgery for intracardiac myxoma (16 left atrial and 2 right atrial) during the last 10 years. Seventeen patients had tumour stalk attached to the oval fossa. The myxoma was excised along with a cuff of the atrial septum, which was reconstructed using a Dacron patch in 15 patients and by direct suture in 2 patients. In the remaining case the myxoma was attached to the left atrial wall and adjacent atrioventricular junction. There was only one early death in a patient who underwent a concomitant lobectomy for lung abscess and one late death due to a noncardiac cause. During the follow-up period of 3-96 months (average 36 months) all the survivors were in New York Heart Association Class I. Scanning electron microscopy of tumour tissue was done in 8 cases. The morphological findings did not help in categorizing the tumours into any pathological subgroups. Postoperative cardiac catheterization done in 3 patients (30-50 months postoperatively) showed return of haemodynamics to normal. Echocardiographic studies done postoperatively have not revealed recurrence of tumour in any patient. Surgical excision of myxomas is possible with very gratifying long-term results.


Assuntos
Neoplasias Cardíacas/cirurgia , Mixoma/cirurgia , Adolescente , Adulto , Ecocardiografia , Feminino , Seguimentos , Átrios do Coração/patologia , Átrios do Coração/cirurgia , Neoplasias Cardíacas/patologia , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Mixoma/patologia
12.
Indian Heart J ; 42(6): 415-7, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2098313

RESUMO

Presence of Aschoff nodules and other chronic inflammatory cells in the left atrial appendage even in the absence of rheumatic activity has been reported in a high percentage of patients with chronic rheumatic valvular heart disease. This study was conducted on 37 left atrial appendages resected at the time of closed mitral valvotomy. Aschoff nodules were present in 61.2 percent of resected appendages, positivity being 71.4 percent in the age group of 20 years of less and 53.3 percent in patients more than 20 years of age. The histological findings did not change significantly in the presence of activity. The frequency of Aschoff nodules and chronic inflammatory cells and their subtypes also did not show any correlation with age, sex, duration of symptoms or severity of mitral stenosis.


Assuntos
Átrios do Coração/patologia , Valva Mitral/patologia , Cardiopatia Reumática/patologia , Nódulo Reumático/patologia , Adulto , Feminino , Doenças das Valvas Cardíacas/metabolismo , Doenças das Valvas Cardíacas/patologia , Doenças das Valvas Cardíacas/cirurgia , Humanos , Imuno-Histoquímica , Masculino , Valva Mitral/cirurgia , Cardiopatia Reumática/metabolismo , Cardiopatia Reumática/cirurgia
14.
18.
Clin Radiol ; 43(3): 162-5, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2013190

RESUMO

Extracranial carotid artery aneurysms secondary to accidental injury are rare. We have seen eight lesions of this type in the last 10 years. The aneurysm was produced by blunt trauma in four patients, penetrating shrapnel injury in two, stabbing and electrical injury in one each. The left side was involved in seven patients. The internal and common carotid artery were each involved in four patients and the lesion was unilocular in five. These lesions often produce non-specific symptoms and may mimic neoplastic or inflammatory masses: a mistaken diagnosis of tonsillar abscess in one patient resulted in incision and drainage before an intravenous digital subtraction angiogram (IV-DSA) correctly identified the abnormality. IV-DSA is ideal for pre-operative assessment of these patients. Awareness of these lesions is essential since definitive surgical repair is possible. All patients in the present study underwent successful surgical repair.


Assuntos
Aneurisma/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Adolescente , Adulto , Aneurisma/etiologia , Angiografia Digital , Doenças das Artérias Carótidas/etiologia , Lesões das Artérias Carótidas , Criança , Traumatismos por Eletricidade/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ferimentos não Penetrantes/complicações , Ferimentos Penetrantes/complicações
19.
Artigo em Inglês | MEDLINE | ID: mdl-3387943

RESUMO

Closed mitral valvotomy for rheumatic mitral stenosis was performed on 126 pregnant women (average duration of pregnancy c. 21 weeks), 91% of whom were in NYHA functional class III or IV. Associated functional tricuspid regurgitation was present in 47 (37%) of the women, and 102 (81%) had critical mitral stenosis (digitally assessed valve area less than 1 cm2). There was no surgical mortality. Postoperatively 84% of the women were in NYHA class I. Clinical evidence of pulmonary artery hypertension and tricuspid regurgitation regressed postoperatively in most patients. Full-term normal delivery was achieved in 82% of the pregnancies, with total fetal mortality 6%. There were no congenital abnormalities and the infants' progress was normal. At 5-year follow-up 86% of the women were in NYHA class I or II and at 10 years the figure was 60%. The restenosis rate was 2%/year and the late mortality 3.3%. Closed mitral valvotomy during pregnancy thus was safe and reliable, giving significant functional and clinical improvement without adversely affecting the fetus.


Assuntos
Estenose da Valva Mitral/cirurgia , Complicações Cardiovasculares na Gravidez/cirurgia , Adulto , Fibrilação Atrial/etiologia , Feminino , Morte Fetal/etiologia , Seguimentos , Humanos , Complicações Pós-Operatórias , Gravidez , Resultado da Gravidez , Fibrilação Ventricular/etiologia
20.
Scand J Thorac Cardiovasc Surg ; 22(1): 19-22, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3387945

RESUMO

Pregnancy after valve replacement has been considered hazardous because of maternal and fetal complications secondary to anticoagulant medication, in addition to basic myocardial problems. Of 229 females aged 15-45 years with prosthetic valve replacement, 37 (including 34 with Björk-Shiley valve and anticoagulants) subsequently had a total of 47 pregnancies. Fullterm delivery of a normal infant was achieved in 40 cases. There were three premature births, two spontaneous abortions, one stillbirth and one ectopic pregnancy. The fetal mortality was 8.5%. Valve thrombosis developed in two cases, but surgical treatment was successful. Oral anticoagulants (acenocoumarin and dipyridamole) were continued throughout pregnancy. Heparin was substituted before labour began, but discontinued after delivery, when effective oral anticoagulation was resumed. Our experience showed that pregnancy in women with mechanical heart valve prosthesis and continued oral intake of anticoagulants is safe and successful in most cases.


Assuntos
Próteses Valvulares Cardíacas , Gravidez , Acenocumarol/uso terapêutico , Adolescente , Adulto , Valva Aórtica , Feminino , Morte Fetal/epidemiologia , Doenças das Valvas Cardíacas/etiologia , Doenças das Valvas Cardíacas/prevenção & controle , Humanos , Valva Mitral , Complicações Cardiovasculares na Gravidez/etiologia , Complicações Cardiovasculares na Gravidez/prevenção & controle , Resultado da Gravidez , Trombose/etiologia , Trombose/prevenção & controle
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