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1.
Heart Lung Circ ; 33(10): 1383-1392, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38981831

RESUMEN

AIM: Although current guidelines recommend concomitant tricuspid annuloplasty for moderate or greater tricuspid regurgitation (TR) and/or dilated annulus, there remains significant variation in undertaking concomitant tricuspid valve surgery (TVA) across different centres. This meta-analysis aimed to compare the clinical outcomes of concomitant tricuspid valve surgery for patients with moderate or greater TR and/or dilated annulus at the time of mitral valve (MV) surgery. METHOD: A systematic review of the literature using six databases. Eligible studies include comparative studies on TVA concomitant with MV surgery versus MV surgery alone. A meta-analysis was performed on studies reporting outcomes of interest to quantify the effects of concomitant tricuspid ring annuloplasty. RESULTS: Two randomised controlled trials and six cohort studies were included in the analysis. 1,941 patients were included in the analysis, of whom, 1,090 underwent concomitant TVA and 851 underwent MV surgery alone. Pooled analysis demonstrated that there was less progression of moderate/severe TR in the concomitant group (3.0% vs 9.6%; odds ratio [OR] 0.29; 95% confidence interval [CI] 0.13-0.55; p=0.0001). There was no significant difference in in-hospital mortality (3.0% vs 3.8%; OR 0.79; 95% CI 0.47-1.34; p=0.38). The rate of permanent pacemaker implantation was higher in the concomitant group although this did not reach statistical significance (7.6% vs 5.3%; OR 1.30; 95% CI 0.85-1.98; p=0.23). Cardiopulmonary bypass was longer in the concomitant TVA group by 20 minutes (mean difference 13.9-26.0; p<0.00001). CONCLUSIONS: Our study demonstrated that concomitant tricuspid ring annuloplasty at the time of MV surgery is associated with a significantly lower rate of TR progression without increasing the operative mortality. There is a trend towards a higher permanent pacemaker implantation rate although this did not reach statistical significance.


Asunto(s)
Anuloplastia de la Válvula Cardíaca , Válvula Mitral , Insuficiencia de la Válvula Tricúspide , Válvula Tricúspide , Humanos , Anuloplastia de la Válvula Cardíaca/métodos , Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/cirugía , Válvula Tricúspide/cirugía , Insuficiencia de la Válvula Tricúspide/cirugía
2.
Water Sci Technol ; 86(8): 1969-1980, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36315089

RESUMEN

A surfactant-modified coal fly ash was developed as a multifunctional adsorbent for the removal of organic pollutants from wastewater. Sodium dodecyl sulfate (SDS) was used to modify the surface of coal fly ash (CFA). The modified CFA was characterized using scanning electron microscopy (SEM), surface porosity analyzer, thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopy. The results showed that loading CFA with SDS not only improved the functionality and surface morphology of the raw ash for the adsorption of organic pollutants, but also enhanced its thermal stability. The efficiency of the modified fly ash was tested in terms of removal of two non-polar organic pollutants namely chlorobenzene (CB) and nitrobenzene (NB) from aqueous phase. The maximum uptake capacity of chlorobenzene and nitrobenzene with SDS-modified coal fly ash (SCFA) was 225 mg/g and 90 mg/g, respectively. The kinetic analysis was done by controlled kinetic models, i.e., pseudo first and second order kinetic models. The results showed that adsorption of CB and NB onto SCFA followed a pseudo second order kinetic model. The adsorption of chlorobenzene was exothermic over the modified adsorbent while nitrobenzene showed an endothermic behavior. The isotherm analysis depicted the multilayer adsorption of both pollutants onto the surface of the surfactant modified adsorbent. This work has shown that surface modification using surfactants can be a viable option to enhance the adsorption capacity of fly ash for pollutants removal.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Aguas Residuales , Ceniza del Carbón/química , Benceno , Cinética , Tensoactivos , Contaminantes Químicos del Agua/química , Adsorción , Carbón Mineral , Nitrobencenos , Clorobencenos , Concentración de Iones de Hidrógeno
3.
Waste Manag Res ; 38(11): 1284-1294, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32347191

RESUMEN

Biomass is considered as the largest renewable energy source in the world. However, some of its inherent properties such as hygroscopicity, lower energy content, low mass density and bio-degradation on storage hinder its extensive application in energy generation processes. Torrefaction, a thermochemical process carried out at 200-300°C in a non-oxidative environment, can address these inherent problems of the biomass. In this work, torrefaction of bagasse was performed in a bench-scale tubular reactor at 250°C and 275°C with residence times of 30, 60 and 90 mins. The effects of torrefaction conditions on the elemental composition, mass yield, energy yield, oxygen/carbon (O/C) and hydrogen/carbon (H/C) ratios, higher heating values and structural composition were investigated and compared with the commercially available 'Thar 6' and 'Tunnel C' coal. Based on the targeted mass and energy yields of 80% and 90% respectively, the optimal process conditions turned out to be 250°C and 30 mins. Torrefaction of the bagasse conducted at 275°C and 90 min raised the carbon content in bagasse to 58.14% and resulted in a high heating value of 23.84 MJ/kg. The structural and thermal analysis of the torrefied bagasse indicates that the moisture, non-structural carbohydrates and hemicellulose were reduced, which induced the hydrophobicity in the bagasse and enhanced its energy value. These findings showed that torrefaction can be a sustainable pre-treatment process to improve the fuel and structural properties of biomass as a feedstock for energy generation processes.


Asunto(s)
Carbono , Celulosa , Biomasa , Hidrógeno , Temperatura
4.
Waste Manag Res ; 37(7): 737-745, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30945613

RESUMEN

Torrefaction, is a pretreatment process in the conversion of various biomass feedstocks into an efficient solid fuel. In the present research, rice husk was torrefied at 200°C, 250°C, and 300°C for 10, 30, 90, and 150 minutes under a non-oxidative environment. The energy yield and mass yield of torrefied solid residues ranged from 51.3% to 96.8%, and 49.1% to 95.1%, respectively, under torrefaction conditions. Increasing the residence time and temperature of thermal treatment causes a rise in carbon content from 32.45% to 48.5%, and raises the calorific value from 16.48 MJ/kg to 19.82 MJ/kg. The torrefaction process also reduced the swelling tendency of the biomass in water from its initial value of 308% to 92% only. Various other characterizations including Fourier transform infrared radiation, thermogravimetric analysis (TGA) and scanning electron microscopy were performed to analyze the structural and textural aspects of torrefied biomass. The TGA and derivative thermogravimetric analysis curves indicated that torrefaction affected the hemicellulose fraction of biomass significantly. The surface morphology of thermolyzed samples revealed the rupture of the surface induced by the torrefaction process. Overall, the torrefaction process has not only improved the fuel characteristics of the rice husk but also enhanced its hydrophobicity.


Asunto(s)
Oryza , Biomasa , Temperatura , Agua
5.
Drug Metab Dispos ; 42(12): 2016-22, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25233858

RESUMEN

Due to the rapid turnover of the small intestinal epithelia, the rate at which enterocyte renewal occurs plays an important role in determining the level of drug-metabolizing enzymes in the gut wall. Current physiologically based pharmacokinetic (PBPK) models consider enzyme and enterocyte recovery as a lumped first-order rate. An assessment of enterocyte turnover would enable enzyme and enterocyte renewal to be modeled more mechanistically. A literature review together with statistical analysis was employed to establish enterocyte turnover in human and preclinical species. A total of 85 studies was identified reporting enterocyte turnover in 1602 subjects in six species. In mice, the geometric weighted combined mean (WX) enterocyte turnover was 2.81 ± 1.14 days (n = 169). In rats, the weighted arithmetic mean enterocyte turnover was determined to be 2.37 days (n = 501). Humans exhibited a geometric WX enterocyte turnover of 3.48 ± 1.55 days for the gastrointestinal epithelia (n = 265), displaying comparable turnover to that of cytochrome P450 enzymes in vitro (0.96-4.33 days). Statistical analysis indicated humans to display longer enterocyte turnover as compared with preclinical species. Extracted data were too sparse to support regional differences in small intestinal enterocyte turnover in humans despite being indicated in mice. The utilization of enterocyte turnover data, together with in vitro enzyme turnover in PBPK modeling, may improve the predictions of metabolic drug-drug interactions dependent on enzyme turnover (e.g., mechanism-based inhibition and enzyme induction) as well as absorption of nanoparticle delivery systems and intestinal metabolism in special populations exhibiting altered enterocyte turnover.


Asunto(s)
Mucosa Intestinal/metabolismo , Preparaciones Farmacéuticas/metabolismo , Animales , Simulación por Computador , Sistema Enzimático del Citocromo P-450/metabolismo , Interacciones Farmacológicas/fisiología , Enterocitos/metabolismo , Humanos , Absorción Intestinal/fisiología , Intestino Delgado/metabolismo , Ratones , Modelos Biológicos , Ratas
6.
J Coll Physicians Surg Pak ; 34(9): 1051-1055, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39262004

RESUMEN

OBJECTIVE: To establish the diagnostic utility of immunohistochemistry markers p16 along with MDM2 and CDK-4 in confirming the diagnosis of well-differentiated and de-differentiated liposarcoma while taking Fluorescent in situ Hybridisation (FISH) as a gold standard. STUDY DESIGN: A cross-sectional study. Place and Duration of the Study: Department of Histopathology, Armed Forces Institute of Pathology, Rawalpindi, Pakistan, from 30th January 2022 to 30th June 2023. METHODOLOGY: A standard panel of three immunohistochemistry markers p16, MDM2, and CDK4 were applied to 36 cases of atypical lipomatous tumours, well-differentiated liposarcoma (WDLPS), and de-differentiated liposarcoma (DDLPS), on which the gold standard FISH was already performed. The sample size was calculated with the help of a WHO calculator taking prevalence 1-2% in Pakistani population. Qualitative variables such as gender and site of tumour were presented by calculating frequency and percentages and comparison of Immunohistochemistry results with FISH was done by using a 2x2 table. RESULTS: The sensitivity and specificity of this triple marker panel for detecting WDLPS/DDLPS were 43.47% and 15.38%, respectively. The sensitivity and specificity of CDK4 for detecting WDLPS / DDLPS were 82.6% and 15.4%, those of MDM2 were 73.9% and 61.5 %, and those of p16 were 60.9% and 53.8%, respectively. CONCLUSION: Among all three markers, CDK4 was the most sensitive and MDM2 was the most specific marker for detecting WDLPS-DDLPS. It also showed that a combination of these three markers improves the diagnostic credibility of the immunohistochemistry in diagnosing DDLPS and WDLPS but FISH is the most reliable and confirmatory method. KEY WORDS: De-differentiated liposarcoma, Well-differentiated liposarcoma, P16, CDK4, MDM2.


Asunto(s)
Biomarcadores de Tumor , Quinasa 4 Dependiente de la Ciclina , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Inmunohistoquímica , Hibridación Fluorescente in Situ , Liposarcoma , Proteínas Proto-Oncogénicas c-mdm2 , Humanos , Liposarcoma/diagnóstico , Liposarcoma/patología , Liposarcoma/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Quinasa 4 Dependiente de la Ciclina/metabolismo , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Femenino , Masculino , Biomarcadores de Tumor/metabolismo , Estudios Transversales , Persona de Mediana Edad , Adulto , Sensibilidad y Especificidad , Anciano
7.
Clin Case Rep ; 11(5): e7177, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37215969

RESUMEN

Management of infective endocarditis (IE) in intravenous drug users (IVDUs) can be challenging due to risk of reinfection following surgery. Although complex repair techniques that can be utilized to reconstruct the tricuspid valve after extensive debridement, treatment of active IVDU is incomplete without effective post-operative harm reduction intervention program.

8.
Environ Sci Pollut Res Int ; 30(31): 77165-77180, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37249783

RESUMEN

In this research study, waste fly ash (WFA) underwent acid activation and subsequent amine functionalization using ammonia solution. This treatment improves the porosity, thermal tendency and crystallinity of WFA. Modified WFA was tested under different experimental conditions to treat the wastewater consisting of different concentrations of cationic (methylene blue and rhodamine 6G) and anionic (methyl orange) dyes. As an individual, methylene blue (MB) and rhodamine 6G (Rh) showed ~ 100% and ~ 82% removal efficiencies respectively in an alkaline medium while methyl orange (MO) exhibited only ~ 20% adsorption in the same medium. An antagonistic effect was observed in adsorption when wastewater contains both cationic dyes whereas the combination of cationic and anionic dyes in solution manifested a synergistic effect. For all individual and binary dye combinations, there is a close agreement in observed and calculated uptakes when the data was fitted to the fractional order kinetic rate equation. The adsorption of all dyes is spontaneous and endothermic in nature except for MB/MO combination where the process is exothermic in nature. 24.93 mg/g, 24.83 mg/g, and 14.95 mg/g monolayer uptake capacities of MB, Rh, and MO were found respectively from isothermal analysis of single dye adsorption data. Further, extended sips model gave higher correlation coefficient (R2 = 0.99) and addressed the failed assumptions of both the Langmuir and Freundlich models. Overall, in the experimental results, the modified waste fly ash could act as successful adsorbent to treat dye bearing wastewater.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Colorantes , Ceniza del Carbón , Azul de Metileno , Cinética , Adsorción , Cationes
9.
J Cardiothorac Surg ; 16(1): 78, 2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-33849600

RESUMEN

BACKGROUND: Congenital pulmonary airway malformation (CPAM) with partial anomalous pulmonary venous connection presenting as episodic retrosternal chest pain on exertion in an adult has not been described. CASE PRESENTATION: A 21-year-old female, non-smoker, presented with a 4-year history of sharp, episodic, retrosternal chest pains brought on with exercise. A contrast-enhanced computed tomography (CT) scan showed a grossly overinflated left lower lobe with partial anomalous pulmonary venous drainage into the left hemi-azygos vein. Lobectomy, the recommended treatment of choice, carried out thoracoscopically, was curative with satisfactory mid-term results. Histology confirmed type-II congenital pulmonary airway malformation. CONCLUSIONS: CPAM can present in young adults with unusual symptoms of chest pain on exertion. When suspected a contrast-enhanced CT scan is the gold standard for establishing the diagnosis. An anatomical lung resection is curative with satisfactory medium term results.


Asunto(s)
Dolor en el Pecho/etiología , Malformación Adenomatoide Quística Congénita del Pulmón/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Malformación Adenomatoide Quística Congénita del Pulmón/complicaciones , Malformación Adenomatoide Quística Congénita del Pulmón/cirugía , Femenino , Humanos , Adulto Joven
10.
Rice (N Y) ; 12(1): 61, 2019 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-31399885

RESUMEN

BACKGROUND: Arsenic (As) is an unwanted toxic mineral that threatens the major rice-growing regions in the world, especially in South Asia. Rice production in Bangladesh and India depends on As-contaminated groundwater sources for irrigating paddy fields, resulting in elevated amounts of As in the topsoil. Arsenic accumulating in rice plants has a significant negative effect on human and animal health. Here, we present a quantitative trait locus (QTL) mapping study to identify candidate genes conferring As toxicity tolerance and accumulation in rice (Oryza sativa L.) seedlings. An early backcross breeding population consisting of 194 lines derived from a cross between WTR1 (indica) and Hao-an-nong (japonica) was grown in hydroponics for 25 days, from the seventh day exposed to an environmentally relevant concentration of 10 ppm As. RESULTS: Arsenic toxicity leads to significantly negative plant responses, including reduced biomass, stunted plant growth, reduced leaf chlorophyll content, and increased shoot As concentration ranging from 9 to 20 mg kg- 1. Marker-trait association was determined for seven As-related traits using 704 single nucleotide polymorphism (SNP) markers generated from a 6 K SNP-array. One QTL was mapped on chromosome 1 for relative chlorophyll content, two QTLs for As content in roots were mapped on chromosome 8, and six QTLs for As content in shoots were mapped on chromosomes 2, 5, 6, and 9. Using the whole-genome sequence of the parents, we narrowed down the number of candidate genes associated with the QTL intervals based on the existence of a non-synonymous mutation in genes between the parental lines. Also, by using publicly available gene expression profiles for As stress, we further narrowed down the number of candidate genes in the QTL intervals by comparing the expression profiles of genes under As stress and control conditions. Twenty-five genes showing transcription regulation were considered as candidate gene nominees for As toxicity-related traits. CONCLUSIONS: Our study provides insight into the genetic basis of As tolerance and uptake in the early seedling stage of rice. Comparing our findings with the previously reported QTLs for As toxicity stress in rice, we identified some novel and co-localized QTLs associated with As stress. Also, the mapped QTLs harbor gene models of known function associated with stress responses, metal homeostasis, and transporter activity in rice. Overall, our findings will assist breeders with initial marker information to develop suitable varieties for As-contaminated ecosystems.

11.
Front Plant Sci ; 9: 849, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29988489

RESUMEN

This study demonstrates genotyping-by-sequencing-based single-nucleotide polymorphism (SNP)-typing in 11 early-backcross introgression populations of rice (at BC1F5), comprising a set of 564 diverse introgression lines and 12 parents. Sequencing using 10 Ion Proton runs generated a total of ∼943.4 million raw reads, out of which ∼881.6 million reads remained after trimming for low-quality bases. After alignment, 794,297 polymorphic SNPs were identified, and filtering resulted in LMD50 SNPs (low missing data, with each SNP, genotyped in at least 50% of the samples) for each sub-population. Every data point was supported by actual sequencing data without any imputation, eliminating imputation-induced errors in SNP calling. Genotyping substantiated the impacts of novel breeding strategy revealing: (a) the donor introgression patterns in ILs were characteristic with variable introgression frequency in different genomic regions, attributed mainly to stringent selection under abiotic stress and (b) considerably lower heterozygosity was observed in ILs. Functional annotation revealed 426 non-synonymous deleterious SNPs present in 102 loci with a range of 1-4 SNPs per locus and 120 novel SNPs. SNP-typing this diversity panel will further assist in the development of markers supporting genomic applications in molecular breeding programs.

12.
J Surg Educ ; 74(2): 372-376, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27789191

RESUMEN

BACKGROUND: The cardiothoracic surgical (CTS) specialty has witnessed a decline in the applicant pool. Early exposure, positive experiences, inspiring role models, and career insight are key in the decision-making process for specialty choice. Our objective was to assess the effect of high tutor:student ratio interactive CTS workshops in influencing the career choice of UK undergraduate medical students. METHODS: Medical students attended a workshop comprising (1) guided dissection of fresh animal hearts, (2) surgical skills practice on models and fresh hearts, (3) operative videos (adult, congenital, transplant, and aortic) with interactive commentary, and (4) careers seminar. The tutor:student ratio was very high (between 3-1 and 5-1). A questionnaire was completed at the end of each workshop to assess its effect, including a 10-point Likert scale on the perceived attraction to CTS before and after the workshop. RESULTS: A total of 96 delegates attended 5 workshops in 3 UK medical schools. Response rate was 83% from 80 undergraduate students. In all, 58% were male (46/80). There was an equal proportion of sexes in the early years of medical school, but was significantly skewed toward male in the later years. There was a statistically significant increase of 2.1 (standard deviation [SD] = 1.5) in the Likert scores before (µ = 5.0, SD = 2.1) and after (µ = 7.1, SD = 1.9) (p = 0.001). This represents a 42% increase in the perceived attraction to the CTS specialty because of the workshops. CONCLUSIONS: Our workshops have a significant effect in stimulating undergraduate medical students toward a career in cardiothoracic surgery. We encourage national take-up of these easily organized daylong workshops to foster interest in the next generation of cardiothoracic surgeons.


Asunto(s)
Selección de Profesión , Educación de Pregrado en Medicina/métodos , Educación/organización & administración , Encuestas y Cuestionarios , Procedimientos Quirúrgicos Torácicos/educación , Toma de Decisiones , Femenino , Humanos , Masculino , Innovación Organizacional , Evaluación de Programas y Proyectos de Salud , Facultades de Medicina/organización & administración , Estudiantes de Medicina/psicología , Estudiantes de Medicina/estadística & datos numéricos , Reino Unido , Adulto Joven
13.
Ann Thorac Surg ; 101(1): 329-32, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26694267

RESUMEN

PURPOSE: We report a technique of finite-element multidimensional modeling that was used to help with the planning of and the resection of an angiosarcoma in a single patient. DESCRIPTION: A patient was referred to our department with suspected aortic angiosarcoma. We visualized and reconstructed the computed tomography and magnetic resonance imaging scans of this patient to create finite-element multidimensional models of his diseased aorta. EVALUATION: This technique and the multidimensional models were very helpful in assessing the tumor size and its extension. It also facilitated preoperative planning of the aortic resection and repair. CONCLUSION: Finite-element multidimensional modeling is a useful technique for preoperative planning of aortic operations in patients with angiosarcoma.


Asunto(s)
Simulación por Computador , Hemangiosarcoma/diagnóstico , Imagenología Tridimensional , Imagen por Resonancia Cinemagnética/métodos , Tomografía Computarizada Multidetector/métodos , Estadificación de Neoplasias/métodos , Neoplasias Vasculares/diagnóstico , Análisis de Elementos Finitos , Hemangiosarcoma/cirugía , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Neoplasias Vasculares/cirugía , Procedimientos Quirúrgicos Vasculares/métodos
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