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1.
Kathmandu Univ Med J (KUMJ) ; 21(81): 79-84, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37800431

RESUMO

Background Low cardiac output syndrome (LCOS) is a serious complication after coronary artery bypass grafting (CABG) surgery. It is associated with 10 times to 17 times increase in mortality and markedly increase morbidity. Objective To find out the frequency of Low cardiac output syndrome following on pump coronary artery bypass grafting surgery, to determine the association of Low cardiac output syndrome with degree of pre-operative left ventricular dysfunction and to compare in hospital outcomes of coronary bypass surgery with and without low cardiac output syndrome. Method This prospective, descriptive study enrolled 200 patients who underwent on pump coronary artery bypass grafting surgery using antegrade St Thomas blood cardioplegia. Pre-operatively grouped into two groups consisting Group A of 100 patients with pre-operative left ventricular ejection fraction (LVEF) ≥ 40% and group B of 100 patients with pre-operative left ventricular ejection fraction (LVEF) < 40%. Post-operatively frequency of low cardiac output syndrome was compared between the groups and in-hospital outcomes were studied. Result The mean age of the patients in the study was 53.50±7.57 years. Male to female ratio was 1.8:1. Results showed overall frequency of low cardiac output syndrome was 21.5%. The frequency of LCOS was 15 vs 28% (p - 0.038) in patients with preoperative LV EF ≥ 40% and < 40% respectively. The outcomes of coronary artery bypass grafting surgery were stroke (3.82 vs. 30.23%, p - 0.001), acute kidney injury (5.09 vs. 23.25%, p - 0.001), respiratory failure (6.36 vs. 34.88%, p - 0.001), ICU stay days (4.75 ± 1.28 vs. 7.44 ± 4.66, p - 0.018), hospital stay days (9.56 ± 2.40 vs. 15.22 ± 3.89, p - 0.001) and mortality (4.45 vs. 32.55%, p - 0.001) in patients without and with low cardiac output syndrome respectively. Conclusion The frequency of low cardiac output syndrome following coronary artery bypass surgery is 21.5%. Left ventricular dysfunction pre-operatively is associated with high frequency of low cardiac output syndrome following surgery. There is significantly poor outcome of coronary artery bypass surgery with low cardiac output syndrome in terms of stroke, respiratory failure, acute kidney injury, mortality and significant ICU stay, hospital stay in compare to patients without low cardiac output syndrome.


Assuntos
Injúria Renal Aguda , Insuficiência Respiratória , Acidente Vascular Cerebral , Disfunção Ventricular Esquerda , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Baixo Débito Cardíaco/etiologia , Baixo Débito Cardíaco/complicações , Volume Sistólico , Função Ventricular Esquerda , Estudos Prospectivos , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/métodos , Disfunção Ventricular Esquerda/complicações , Insuficiência Respiratória/complicações , Acidente Vascular Cerebral/complicações , Resultado do Tratamento
3.
Rev Sci Instrum ; 94(2): 023303, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859052

RESUMO

The design and performance of an in-house developed double-solenoid magnetic bottle (MB) time-of-flight photoelectron spectrograph are presented. A combination of a strong permanent magnet (Sm2Co17) with a soft iron cone and a double-solenoid geometry is used to generate MB configuration. The first solenoid (length ∼150 mm) is placed inside the vacuum, and the second solenoid (length ∼1 m) is placed outside the vacuum. The double-solenoid geometry improves the effective conductance and reduces overall material outgassing. Due to this, an ultra-high vacuum (∼5 × 10-8 mbar) desirable for the working of the spectrograph was achieved using a small capacity (300 lps) turbo-molecular pump. An optimization of solenoid current generates a smooth magnetic field variation in MB, which keeps the adiabaticity parameter ∼0.6 at ∼25 eV photoelectron energy. The double-solenoid geometry also provides high collection efficiency as well as high energy resolution of the spectrograph. The experimentally measured energy resolution (ΔE) of the spectrograph is better than ∼60 meV at ∼15 eV photoelectron energy. The collection efficiency is estimated to be ∼25% under optimum conditions as compared with ∼10-4 in field-free configuration. The calibrated MB spectrograph is used for the characterization of the attosecond pulse train using a cross-correlation "RABBITT" technique. The attosecond pulse train is generated from 15th to 25th odd high-harmonic orders, in argon filled cell. Attosecond pulses of average duration ∼260 as (FWHM) have been measured. The proposed MB electron spectrograph design provides a compact experimental setup for attosecond metrology and pump-probe studies with a relaxed requirement on vacuum pump capacity.

4.
Sci Rep ; 12(1): 16636, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36198707

RESUMO

In regions with limited potable water availability, membrane desalination is being employed to filter water using a pressure-driven approach. Because of the high energy consumption required to produce the pressure differential needed for this method, researchers have been trying different geometric designs of spacer filaments to enhance the amount of permeate flux in terms of energy utilization. The purpose of spacer filaments is to support membranes structurally and induce turbulent mixing in spiral wound membrane desalination. In this paper, the improvement of mass transfer in desalination driven by reverse osmosis has been studied using Computational Fluid Dynamics (CFD) with the introduction of spiral wound membranes that are lined with spacer filaments in a zig-zag formation having alternating diameters for strands. The fluid flow characteristics for a 2-dimensional geometric model were resolved using the open-source program OpenFOAM by changing the Reynolds number to just before the inception of instabilities. Ratios of alternate strand diameters were also varied between one and two. Based on a detailed analysis of velocity contours, pressure distribution, wall shear stresses, and steady-state vortex systems, the research findings offer guidance for employing alternating strand design in zig-zag formation for optimum mass transfer and minimal pressure drop when accounting for concentration polarization.


Assuntos
Incrustação Biológica , Água Potável , Purificação da Água , Membranas Artificiais , Osmose , Purificação da Água/métodos
5.
Chemosphere ; 306: 135649, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35817183

RESUMO

In recent years groundwater modelling has become a major part of many projects dealing with groundwater exploitation, protection and remediation. Coimbatore city is located along the Noyyal River which is grown in size and population on either side of the river and the dumping of wastes very close to the river banks, leads to pollution of both surface and groundwater. Study on the quality of groundwater along the Noyyal River in Coimbatore city of Tamilnadu, is necessary to safeguard the interest of the people with respect to quality and quantity of water. The objective of the research is to develop Groundwater quality models to suggest ways and means to contain and remediate the polluted groundwater under various conditions. Data related to the groundwater quality, rainfall and well log were collected from the reputed government departments and fifteen sample well locations are identified near the noyyal river basin. The quality parameters such as pH, TDS, EC, TH, chlorides, alkalinity, sodium, calcium, magnesium, sulphates and nitrates are considered for the study. Groundwater quality modelling is attempted by using MODFLOW/MT3DMS with different scenarios. This study revealed that in all the scenarios the center portion of study area is more affected i.e. from P·N.Palayam to Kalangal. The groundwater flow is moving towards and along the river flow. Hence the pollutants are moving easily from upstream to the downstream side. necessary measures has to be taken to control the groundwater contamination.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental , Humanos , Nitratos/análise , Rios , Poluentes Químicos da Água/análise , Qualidade da Água
6.
Tech Coloproctol ; 26(4): 291-300, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35094202

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) is used as a standard for assessment of complex perianal fistulas. Apart from textual description of the case, 3D reconstructed models from MRI further aid in understanding the entire anatomy of the fistula tract and its relation to the pelvic floor. This information is crucial as it helps surgeons to understand the extent and complexity of the disease before surgical treatment. However, 3D model generation from MRI is a time-consuming step for a radiologist as it requires tedious manual delineations to be performed on every slice of the images. The aim of this study was to develop a method that could enable radiologists to present enhanced information to surgeons for treatment of complex perianal fistulas while simultaneously reducing the manual efforts and time required to generate the information. METHODS: A method was proposed to depict relevant anatomies of complex perianal fistula as parametric models in three-dimensional (3D) space. A plugin inside 3D Slicer software was developed for the generation of the parametric models from MRI. The levator ani muscle, internal sphincter, and external sphincter are represented as tubular structures, whereas fistula tracks and abscess are presented as splines. RESULTS: Parametric models were generated to depict three cases of complex perianal fistulas and similarity measures were computed for ten cases. Visual comparison of the parametric models was made with the 3D models generated by the standard approach. The parametric models took less time to create and were able to visually present enriched information as compared to the 3D models generated by the standard approach. CONCLUSIONS: The proposed method, using parametric models, shows potential for faster generation and better visualization of the 3D information required for the treatment of complex perianal fistula cases.


Assuntos
Fístula Cutânea , Fístula Retal , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Diafragma da Pelve , Fístula Retal/diagnóstico por imagem , Fístula Retal/cirurgia
10.
J Pharm Policy Pract ; 13: 45, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695427

RESUMO

Drug repositioning is the scientific strategy of investigating existing drugs for additional clinical indications. The advantages of drug repositioning are that it benefits patients and that it adds new indications to existing drugs for lower costs compared to de novo drug development. Clinical research groups recognizing efficacy of these "old" drugs for a new indications often face an uphill struggle due to a lack of funding and support because of poor structural and regulatory support for clinical drug development. The current framework for drug repositioning allows "venture capital" companies to abuse loopholes in the legislation to gain long-term market authorization among with excessive high pricing. A new regulatory framework is needed to prevent abuse of the legislation and promote clinical investigator-driven drug repositioning. The COVID-19 pandemic has boosted funding and regulatory support for drug repositioning. The lessons learned from the COVID-19 pandemic should be implemented in a new clear blueprint for drug repositioning. This blueprint should guide clinicians through legislation for drug repositioning in the EU. This review summarizes the routes for registration and discusses the current state of drug repositioning in Europe.

11.
Saudi J Biol Sci ; 27(4): 1124-1129, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32256174

RESUMO

The phenomenal increase in the demand of herbal drugs, leads to over exploitation of medicinal plants which ultimately resulted in the scarcity and endangerment of many valuable plant species. On observing the difficulties in procuring genuine herbal drugs arose the concept of substitution which was documented in many classical Ayurvedic texts. The present study made a comparative evaluation of the gastroprotective potential of hydroalcoholic extracts of an original drug Aconitum heterophyllum (HAAH) and its substitute Cyperus rotundus (HACR) in the treatment of gastric ulcer under in vivo experimental conditions. The anti-ulcer property of the plant extracts was investigated against pylorus ligation induced ulcer in Wistar albino rats. The results confirmed that both A. heterophyllum and C. rotundus deliver comparable significant protection against gastric ulcer, indicated by a decrease in the free and total acidity, volume of gastric content, total proteins and increase in pH of gastric content, total carbohydrates and total carbohydrates to total proteins ratio. The observed anti-ulcer potential of both the drugs is attributed mainly to prevention of the generation of damaging free radical cascades and oxidant radical release.

13.
Health Phys ; 119(2): 163-175, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913861

RESUMO

In the event of a radiological incident, the release of fission products into the surrounding environment and the ensuing external contamination present a challenge for triage assessment by emergency response personnel. Reference exposure rate and skin dose rate calibration data for emergency response personnel are currently lacking for cases where receptors are externally contaminated with fission products. Simulations were conducted to compute reference exposure rate coefficients and skin dose rate coefficients from photon-emitting fission products of radiological concern. To accomplish this task, simplified mathematical skin phantoms were created using surface area and height specifications from International Commission on Radiological Protection Publication 89. Simulations were conducted using Monte Carlo radiation transport code using newborn, 1-y-old, 5-y-old, 10-y-old, 15-y-old, and adult phantoms for 22 photon-emitting radionuclides. Exposure rate coefficient data were employed in a case study simulating the radionuclide inventory for a 17 × 17 Westinghouse pressurized water reactor, following three burn-up cycles at 14,600 MWd per metric ton of uranium. The decay times following the final cycle represent the relative activity fractions over a period of 0.5-30 d. The resulting data can be used as calibration standards for triage efforts in emergency response protocols.


Assuntos
Exposição à Radiação/prevenção & controle , Proteção Radiológica/métodos , Adolescente , Adulto , Calibragem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Cinética , Masculino , Modelos Estatísticos , Método de Monte Carlo , Imagens de Fantasmas , Fótons , Doses de Radiação , Proteção Radiológica/estatística & dados numéricos , Liberação Nociva de Radioativos , Medição de Risco , Pele
14.
J Chem Phys ; 151(22): 224707, 2019 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-31837670

RESUMO

Pt and Rh nanoclusters, grown on deposition of Pt and Rh vapors onto graphene/Pt(111), show separate reactivity toward the decomposition of methanol-d4. The Pt (Rh) clusters had a mean diameter 2.0-3.5 nm (2.1-4.0 nm) and height 0.45-0.94 nm (0.41-0.9 nm) evolving with the coverage; they were structurally ordered, having an fcc phase and growing in (111) orientation, and had lattice constants similar to their bulk values. Methanol-d4 on the Pt clusters did not decompose but desorbed mostly, disparate from that on Pt(111) surface; the disparity arose as the adsorption energies of methanol-d4 on most surface sites of the Pt clusters became smaller than their single crystal counterpart. This size effect, nevertheless, did not apply on the Rh clusters, despite their similar atomic stacking; the Rh clusters showed a reactivity similar to that of the Rh(111) surface because the adsorption energies of methanol-d4 on both Rh clusters and Rh(111) are comparable. The distinct size dependence was rationalized through their electronic structures and charge distribution of Fukui function mapping. Our results suggest that reactive transition metals do not necessarily become more reactive while they are scaled down to nanoscale; their reactivity evolves with their size in a manner largely dependent on their electronic nature.

15.
Urol Case Rep ; 27: 100916, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31687352

RESUMO

Melanosis of the bladder, also known as melanosis vesicae, refers to presence of pigment in bladder mucosa. A rare phenomenon, however, it can be confused with the primary or metastatic melanoma of the bladder. Therefore, knowledge of the entity can prevent over diagnosis of this benign entity. We are reporting a case of melanosis of bladder in a 69 year old male with prolonged history of LUTS and bladder diverticulae. Cystoscopic examination showed black patches and biopsy revealed pigmentation in the epithelium and underlying lamina propria. Special stains identified the pigment to be melanin. No malignant cells were identified.

16.
J Neurol ; 266(11): 2890-2892, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31598874
17.
Sci Rep ; 9(1): 9684, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-31273258

RESUMO

Establishing a cytokine signature associated to some medical condition is an important task in immunology. Increasingly, large numbers of cytokines are used for signatures, via lists of reference ranges for each individual cytokine or ratios of cytokines. Here we argue that this common approach has weaknesses, especially when many different cytokines are analysed. Instead, we propose that establishing signatures can be framed as a multivariate anomaly detection problem, and hence exploit the many statistical methods available for this. In this framework, whether or not a given subject's profile matches the cytokine signature of some condition is determined by whether or not the profile is typical of reference samples of that condition, as judged by an anomaly detection algorithm. We examine previously published cytokine data sets associated to pregnancy complications, brain tumours, and rheumatoid arthritis, as well as normal healthy control samples, and test the performance of a range of anomaly detection algorithms on these data, identifying the best performing methods. Finally, we suggest that this anomaly detection approach could be adopted more widely for general multi-biomarker signatures.


Assuntos
Algoritmos , Artrite Reumatoide/metabolismo , Neoplasias Encefálicas/metabolismo , Citocinas/metabolismo , Hipertensão/metabolismo , Mediadores da Inflamação/metabolismo , Complicações na Gravidez/metabolismo , Artrite Reumatoide/genética , Neoplasias Encefálicas/genética , Citocinas/genética , Conjuntos de Dados como Assunto , Feminino , Perfilação da Expressão Gênica , Humanos , Hipertensão/genética , Análise Multivariada , Gravidez , Complicações na Gravidez/genética
19.
Aging Male ; 22(4): 219-227, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30614347

RESUMO

With prostate cancer not observed in eunuchs and total androgen suppression by castration an effective first-line treatment for advanced prostate cancer, the dramatic regression seen in tumour symptoms after castration, lead to the theory that high levels of circulating androgens were a risk factor for prostate cancer. This theory however, ignored the effects testosterone variations within a physiologic range could have on early tumour events and since the early 2000s, clinical evidence discounting testosterone as a linear mechanistic cause of prostate cancer growth mounted, with alternative mechanistic hypotheses such as the saturation model being proposed. Together with a growing understanding of the negative health effects and decreased quality of life in men with testosterone deficiency or hypogonadism, a paradigm shift away from testosterone as a prostate cancer inducer occurred allowing clinicians to use testosterone therapy as potential treatment for men with difficult and symptomatic hypogonadism that had been previously treated for prostate cancer. In this review we contextualise the idea of testosterone as a risk factor for prostate cancer inducement and compile the most current literature with regards to the influence of testosterone and testosterone therapy in prostate cancer.


Assuntos
Androgênios , Hipogonadismo , Neoplasias da Próstata , Qualidade de Vida , Testosterona , Androgênios/sangue , Androgênios/farmacologia , Humanos , Hipogonadismo/sangue , Hipogonadismo/psicologia , Hipogonadismo/terapia , Masculino , Neoplasias da Próstata/sangue , Neoplasias da Próstata/psicologia , Neoplasias da Próstata/terapia , Fatores de Risco , Testosterona/sangue , Testosterona/farmacologia
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