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1.
Int J Mol Sci ; 25(13)2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-39000545

RESUMEN

Chemotherapy treatment against pancreatic ductal adenocarcinoma (PDAC) is thwarted by tumoral activation of multiple therapy resistance pathways. The growth hormone (GH)-GH receptor (GHR) pair is a covert driver of multimodal therapy resistance in cancer and is overexpressed in PDAC tumors, yet the therapeutic potential of targeting the same has not been explored. Here, we report that GHR expression is a negative prognostic factor in patients with PDAC. Combinations of gemcitabine with different GHR antagonists (GHRAs) markedly improve therapeutic outcomes in nude mice xenografts. Employing cultured cells, mouse xenografts, and analyses of the human PDAC transcriptome, we identified that attenuation of the multidrug transporter and epithelial-to-mesenchymal transition programs in the tumors underlie the observed augmentation of chemotherapy efficacy by GHRAs. Moreover, in human PDAC patients, GHR expression strongly correlates with a gene signature of tumor promotion and immune evasion, which corroborate with that in syngeneic tumors in wild-type vs. GH transgenic mice. Overall, we found that GH action in PDAC promoted a therapy-refractory gene signature in vivo, which can be effectively attenuated by GHR antagonism. Our results collectively present a proof of concept toward considering GHR antagonists to improve chemotherapeutic outcomes in the highly chemoresistant PDAC.


Asunto(s)
Carcinoma Ductal Pancreático , Desoxicitidina , Gemcitabina , Neoplasias Pancreáticas , Receptores de Somatotropina , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Humanos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Desoxicitidina/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Ratones , Receptores de Somatotropina/metabolismo , Receptores de Somatotropina/antagonistas & inhibidores , Receptores de Somatotropina/genética , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/genética , Línea Celular Tumoral , Ratones Desnudos , Resistencia a Antineoplásicos/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Femenino
2.
Dis Colon Rectum ; 65(3): e184-e190, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34856590

RESUMEN

BACKGROUND: We describe a natural orifice technique for simultaneous endoluminal lateral suspension of apical vaginal wall and rectal prolapse fixation with ultrasound and fluoroscopic assistance. IMPACT OF INNOVATION: The technique is minimally invasive, can be performed under regional anaesthesia, and avoids laparotomy or use of a mesh in addition to preserving the uterus. TECHNOLOGY MATERIALS AND METHODS: This technique involves suprapubic transvaginal ventral suture colposuspension, fixation of the anterior rectal wall to the undersurface of the anterior abdominal wall and tack fixation of the posterior rectal wall to the underlying sacral promontory through a submucosal tunnel performed endoscopically with fluoroscopic and ultrasound assistance. PRELIMINARY RESULTS: Seven patients with a mean age of 63 years were followed between 3 to 11 months. CONCLUSIONS: This is a novel minimally invasive transluminal procedure that repairs concomitant rectal and vaginal prolapse in the same sitting. FUTURE DIRECTIONS: Improvement in the instrument design and incorporation of endoluminal robotic systems will enhance the technical ease. The study needs validation in larger series of patients with longer follow-up.


Asunto(s)
Anestesia de Conducción/métodos , Cirugía Endoscópica por Orificios Naturales , Prolapso Rectal , Prolapso Uterino , Estudios de Factibilidad , Femenino , Fluoroscopía/métodos , Humanos , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Cirugía Endoscópica por Orificios Naturales/instrumentación , Cirugía Endoscópica por Orificios Naturales/métodos , Mejoramiento de la Calidad , Prolapso Rectal/diagnóstico por imagen , Prolapso Rectal/cirugía , Procedimientos Quirúrgicos Robotizados/instrumentación , Procedimientos Quirúrgicos Robotizados/métodos , Cirugía Asistida por Computador/métodos , Dispositivos de Fijación Quirúrgicos , Resultado del Tratamiento , Ultrasonografía Intervencional/métodos , Prolapso Uterino/diagnóstico por imagen , Prolapso Uterino/cirugía
3.
Sensors (Basel) ; 20(18)2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-32967094

RESUMEN

As the expenses of medical care administrations rise and medical services experts are becoming rare, it is up to medical services organizations and institutes to consider the implementation of medical Health Information Technology (HIT) innovation frameworks. HIT permits health associations to smooth out their considerable cycles and offer types of assistance in a more productive and financially savvy way. With the rise of Cloud Storage Computing (CSC), an enormous number of associations and undertakings have moved their healthcare data sources to distributed storage. As the information can be mentioned whenever universally, the accessibility of information becomes an urgent need. Nonetheless, outages in cloud storage essentially influence the accessibility level. Like the other basic variables of cloud storage (e.g., reliability quality, performance, security, and protection), availability also directly impacts the data in cloud storage for e-Healthcare systems. In this paper, we systematically review cloud storage mechanisms concerning the healthcare environment. Additionally, in this paper, the state-of-the-art cloud storage mechanisms are critically reviewed for e-Healthcare systems based on their characteristics. In short, this paper summarizes existing literature based on cloud storage and its impact on healthcare, and it likewise helps researchers, medical specialists, and organizations with a solid foundation for future studies in the healthcare environment.


Asunto(s)
Nube Computacional , Almacenamiento y Recuperación de la Información , Telemedicina , Reproducibilidad de los Resultados
4.
Sensors (Basel) ; 20(21)2020 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-33153217

RESUMEN

The health industry is one of the most auspicious domains for the application of Internet of Things (IoT) based technologies. Lots of studies have been carried out in the health industry field to minimize the use of resources and increase the efficiency. The use of IoT combined with other technologies has brought quality advancement in the health sector at minimum expense. One such technology is the use of wireless body area networks (WBANs), which will help patients incredibly in the future and will make them more productive because there will be no need for staying at home or a hospital for a long time. WBANs and IoT have an integrated future as WBANs, like any IoT application, are a collection of heterogeneous sensor-based devices. For the better amalgamation of the IoT and WBANs, several hindrances blocking their integration need to be addressed. One such problem is the efficient routing of data in limited resource sensor nodes (SNs) in WBANs. To solve this and other problems, such as transmission of duplicate sensed data, limited network lifetime, etc., energy harvested and cooperative-enabled efficient routing protocol (EHCRP) for IoT-WBANs is proposed. The proposed protocol considers multiple parameters of WBANs for efficient routing such as residual energy of SNs, number of hops towards the sink, node congestion levels, signal-to-noise ratio (SNR) and available network bandwidth. A path cost estimation function is calculated to select forwarder node using these parameters. Due to the efficient use of the path-cost estimation process, the proposed mechanism achieves efficient and effective multi-hop routing of data and improves the reliability and efficiency of data transmission over the network. After extensive simulations, the achieved results of the proposed protocol are compared with state-of-the-art techniques, i.e., E-HARP, EB-MADM, PCRP and EERP. The results show significant improvement in network lifetime, network throughout, and end-to-end delay.

5.
Cureus ; 16(4): e58982, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38800254

RESUMEN

INTRODUCTION: When acute kidney damage occurs during pregnancy, it poses a difficult clinical problem. One of the main causes of maternal and fetal morbidity and death is pregnancy-related acute kidney injury (AKI), a significant obstetric complication characterized by a fast deterioration in renal function and several subsequent clinical problems. The objective of the study is to analyze the etiological factors, clinical manifestations, and maternal and fetal outcomes of AKI during pregnancy. MATERIALS AND METHODS: This prospective observational research involved patients hospitalized in the General Medicine and Obstetrics and Gynecology departments at Indira Gandhi Institute of Medical Sciences, Patna, for a year (October 2021 to September 2022) due to obstetric difficulties resulting in acute renal damage. RESULTS: The study included 62 patients with a mean age of 25.08±4.25 years. The majority of patients in our study were aged 18-25 years (38, 61.3%), followed by 26-30 years (19, 30.6%) and >30 years (5, 8.1%). The majority of patients in our study were non-booked (52, 83.9%) and presented as emergency cases, whereas 10 (16.1%) patients had booked. In addition, 34 (54.8%) patients were primigravida, while 28 (45.1%) were multigravida. There were 25 patients in their third trimester (40.3%), 19 who were postpartum (30.6%), 10 who were post-abortion (16.1%), and eight in their second trimester (12.9%). Upon admission, the majority of the patients showed signs of oliguria, accounting for 45 cases (72.6%). This was followed by nine cases of abnormal kidney function (14.5%) and eight cases of anuria (12.9%). Among the other symptoms, fever was observed in 25 cases (40.32%), whereas breathlessness increased to 15 cases (24.19%), edema was present in 14 cases (22.58%), vomiting and altered sensorium were observed in four cases (6.45%), abdominal pain was observed in three cases (4.83%), and burning micturition was observed in two cases (3.22%). The most common causes of AKI in pregnancy in the present study were puerperal sepsis (18 cases, 29.0%), followed by preeclampsia/eclampsia (14 cases, 22.6%), hemorrhagic shock (10 cases, 16.1%), septic abortion (six cases, 9.7%), hyperemesis gravidarum (four cases, 6.5%), acute fatty liver of pregnancy (three cases, 4.8%), disseminated intravascular coagulation (three cases, 4.8%), drug-induced sepsis (two cases, 3.2%), and urosepsis (two cases, 3.2%). Modes of delivery in this study were normal vaginal delivery (32 cases, 51.6%), lower segment cesarean section (21 cases, 33.9%), dilation and evacuation (seven cases, 11.3%), and total hysterectomy (two cases, 3.2%). Hemodialysis was performed in 39 patients (62.9%), and 51 (82.3%) received blood transfusions. The mean systolic and diastolic BP (mmHg) were 111.37±22.60 and 71.40±18.88, respectively. Maternal outcome data revealed that 48 (77.4%) women had fully recovered, eight (12.9%) had not recovered, 43 (69.4%) were lost to follow-up, and two (3.2%) had died. Neonatal outcomes in the present study were as follows: live birth, 43 (69.4%); abortion, eight (12.9%); intrauterine death of the fetus, five (8.1%); and neonatal mortality, six (9.7%). CONCLUSION: The diagnosis and treatment of AKI during pregnancy is a significant challenge for the treating physician because of the pathophysiological changes that occur during pregnancy, the variability of symptoms, and the fact that clinical and laboratory features may occasionally overlap.

6.
Cureus ; 16(6): e62690, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39036153

RESUMEN

Background Acute kidney injury (AKI) is a common and serious condition affecting elderly patients. Despite its significance, comprehensive research focusing specifically on the clinical profile and short-term outcomes of AKI in this vulnerable population is lacking. Objective This study aimed to evaluate the clinical profile and short-term outcomes of AKI in elderly patients admitted to a tertiary care center. Methods A prospective observational study was conducted from December 2023 to March 2024, involving 75 elderly patients (aged ≥65 years) diagnosed with AKI. Baseline demographic data, clinical profiles, laboratory investigations, mortality rate among elderly patients diagnosed with AKI within 30 days of diagnosis, and short-term outcomes were recorded and analyzed. Descriptive statistics and appropriate statistical tests were used for the data analysis. Results The study cohort had a mean age of 72.6 years. Hypertension was present in 55 patients (73.3%), and diabetes mellitus was observed in 30 patients (40.0%). Prerenal causes of AKI were identified in 40 patients (53.3%), while acute tubular necrosis was found in 25 patients (33.3%). Stage 2 AKI was the most common, affecting 35 patients (46.7%). Out of the 75 patients, 15 patients (20.0%) succumbed to AKI within the study period. Deceased patients had longer hospital stays, with a median of 16 days compared to 10 days for survivors. ICU admission was required for 13 of the deceased patients (86.7%), compared to 32 of the surviving patients (53.3%). The need for renal replacement therapy was higher among the deceased patients, with 11 out of 15 patients (73.3%) requiring it, compared to 19 out of 60 surviving patients (31.7%). Renal function recovery was notably lower in the deceased patients. Conclusion AKI in elderly patients was associated with significant morbidity and mortality, highlighting the need for early recognition, appropriate management, and preventive strategies. A comprehensive evaluation of the clinical profile and short-term outcomes of AKI in the elderly population provides valuable insights for optimizing patient care and improving outcomes.

7.
Membranes (Basel) ; 13(1)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36676912

RESUMEN

A composite proton conducting membrane (PCM) was prepared by radiation-induced grafting (RIG) of binary mixtures of 4-vinyl pyridine (4-VP) and 1-vinylimidazole (1-VIm) onto poly(ethylene-co-tetrafluoroethylene) (ETFE) film followed by phosphoric acid (PA) doping. The grafting parameters such as absorbed dose, temperature, monomer concentration, time, and monomer ratio were varied to control the degree of grafting (DG%). The effect of the reactivity ratio of 4-VP and 1-VIm on the composition and degree of monomer unit alternation in the formed graft copolymer was investigated. The changes in the chemical and physical properties endowed by grafting and subsequent PA acid doping were monitored using analytical instruments. The mechanical properties and proton conductivity of the obtained membrane were evaluated and its performance was tested in H2/O2 fuel cell at 120 °C under anhydrous and partially wet conditions. The acid doping level was affected by the treatment parameters and enhanced by increasing DG. The proton conductivity was boosted by incorporating the combination of pyridine and imidazole rings originating from the formed basic graft copolymer of 4-VP/1-VIm dominated by 4-VP units in the structure. The proton conductivity showed a strong dependence on the temperature. The membrane demonstrated superior properties compared to its counterpart obtained by grafting 4-VP alone. The membrane also showed a strong potential for application in proton exchange membrane fuel cells (PEMFC) operating at 120 °C.

8.
Cureus ; 15(7): e41511, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37551236

RESUMEN

Introduction Thrombocytopenia is a commonly observed condition in clinical practice, and its diagnosis is often challenging due to numerous aetiologies and variations in clinical presentation. Early identification of thrombocytopenia and its causes can help prevent life-threatening haemorrhagic manifestations. Methodology A prospective observational study was conducted at a tertiary care hospital from February 2019 to January 2020. This evaluation aimed to determine the causes and prevalence of thrombocytopenia in a tertiary care setting. Patients aged 15 or older with a platelet count of fewer than 150,000/ µL were eligible for inclusion in this evaluation. Investigations for aetiology detection were recommended. Results During the one-year study period, a total of 100 patients, including 58 males and 42 females, with thrombocytopenia were selected for the study. The most common age group affected by thrombocytopenia in this study was between 46 and 55 years old. The most common clinical manifestations observed were generalised weakness (70%), haemorrhagic manifestations (60%), fever (50%), joint pain (37%), splenomegaly (35%), headache (30%), breathlessness (23%), lymphadenopathy (22%), hepatomegaly (24%), and abdominal pain (12%). The most prevalent causes of thrombocytopenia were megaloblastic anaemia (19 cases), dengue fever (15 cases), malaria (11 cases), enteric fever (nine cases), immune thrombocytopenia (ITP) (eight cases), and leukaemia (seven cases). Bleeding was reported as a symptom of thrombocytopenia in 60% of individuals in this study. Conclusion In the study, thrombocytopenia was more common in people aged 46-55 years, and males were more commonly affected than females. Megaloblastic anaemia and infectious disease were the most common causes of thrombocytopenia. Bleeding manifestations were found in 60% of patients with thrombocytopenia.

9.
Environ Sci Pollut Res Int ; 30(55): 116906-116920, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37121947

RESUMEN

A series of fibrous aminated adsorbents for CO2 adsorption were prepared by covalent incorporation of poly (glycidyl methacrylate) (PGMA) by graft copolymerization of GMA onto electron beam (EB) irradiated polyethylenepolypropylene (PE/PP) fibrous sheets and subsequent amination with ethylenediamine (EDA), diethylenetriamine (DETA), or tetraethylenepentamine (TEPA). The physico-chemical properties of the adsorbents were evaluated using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric (TGA), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) analysis. All the adsorbents displayed typic primary and secondary amine features combined with a decrease in both of crystallinity and surface area of PE/PP, and such a decrease was higher in adsorbents with longer aliphatic chain of the amine. Of all adsorbents, TEPA-containing fibres showed the highest CO2 adsorption capacity and thus was further investigated for CO2 capture from CO2/CH4 mixtures of different gas ratios under various pressures and temperatures. The selectivity of CO2 over CH4 and equilibrium isotherms, kinetics, and thermodynamics of the adsorption on the fibrous aminated adsorbent were all investigated. The Sips model was found to best fit the isotherm of CO2 adsorption suggesting the presence of a combination of monolayer and multilayer adsorptions. The adsorption kinetic data was found to best fit Elovich model reflecting chemisorption. The ΔG°, ΔS°, and ΔH° showed positive values suggesting that the adsorption of CO2 on the present fibrous adsorbent was non-spontaneous with an increase in randomness implying that the process was endothermic. Overall, it can be suggested that PE/PP-g-PGMA/TEPA adsorbent has a strong potential for separation of CO2 from NG.


Asunto(s)
Dióxido de Carbono , Contaminantes Químicos del Agua , Dióxido de Carbono/química , Adsorción , Termodinámica , Temperatura , Espectroscopía Infrarroja por Transformada de Fourier , Trietilenofosforamida , Cinética , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/química
10.
Math Biosci Eng ; 20(5): 8208-8225, 2023 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-37161193

RESUMEN

Facial expression is a type of communication and is useful in many areas of computer vision, including intelligent visual surveillance, human-robot interaction and human behavior analysis. A deep learning approach is presented to classify happy, sad, angry, fearful, contemptuous, surprised and disgusted expressions. Accurate detection and classification of human facial expression is a critical task in image processing due to the inconsistencies amid the complexity, including change in illumination, occlusion, noise and the over-fitting problem. A stacked sparse auto-encoder for facial expression recognition (SSAE-FER) is used for unsupervised pre-training and supervised fine-tuning. SSAE-FER automatically extracts features from input images, and the softmax classifier is used to classify the expressions. Our method achieved an accuracy of 92.50% on the JAFFE dataset and 99.30% on the CK+ dataset. SSAE-FER performs well compared to the other comparative methods in the same domain.


Asunto(s)
Aprendizaje Profundo , Reconocimiento Facial , Humanos , Comunicación , Miedo , Procesamiento de Imagen Asistido por Computador
11.
Artículo en Inglés | MEDLINE | ID: mdl-36429909

RESUMEN

Oil spills are environmental pollution events that occur due to natural disasters or human activities, resulting in a liquid petroleum hydrocarbon release in the environment, especially into the marine ecosystem. Once oil spills happen, they cause detrimental consequences to the environment, living organisms, and humans. Although there are increasing oil and gas activities in the Arctic region, which is abundant with undiscovered oil and gas resources, the harsh environmental conditions of the region, such as the ice coverage, cold temperatures, long periods of darkness, and its remoteness, pose significant challenges to managing the risk of accidental oil spills in ice-infested waters. In this paper, a bibliometric analysis has been applied to study the global work on oil spill research in ice-infested waters. The paper aims to present an overview of the available oil spill response methods in ice-infested waters, identify the current trends of the research on oil spills in ice-infested waters, and determine the challenges with the future research directions based on the bibliometric analysis. The analysis includes a total number of 77 articles that have been published in this research field which were available in the Scopus database, involving 193 authors from 17 countries dating from 1960 to September 2022. During the bibliometric analysis, the top five most productive authors and countries as well as the most cited publications on oil spills in ice-infested waters have been identified; the authors' cooperation network and the cooperation network between the countries in oil spills research in ice-infested waters have been created; a co-citation analysis and a terms analysis have been performed to identify the popular terms and topics. For future directions, it is recommended for researchers (1) to study real oil spills as much as possible to obtain a good overview through replication under different situations; (2) to develop a new technique for the careful examination and management of the potential risks; (3) to study oil separation from the recovered oil-ice mixture.


Asunto(s)
Contaminación por Petróleo , Humanos , Contaminación por Petróleo/análisis , Hielo , Ecosistema , Accidentes , Bibliometría
12.
Nanoscale Adv ; 4(13): 2836-2843, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-36131999

RESUMEN

The effect of the copper (Cu) content on Cu oxide loaded onto a carbon nanotube (CuO/CNT) catalyst on the mechanistic, kinetic, and photonic efficiency of the photodegradation of p-chloroaniline (PCA) under visible (Vis) and ultraviolet (UV) light irradiation has been explored. For low-loading (1-5 wt%) CuO/CNTs, photodegradation performed better under UV (>84%) rather than the Vis system; this may be due to the presence of abundant defect sites on both CuO and CNTs, which allowed the multielectron reduction of oxygen at their impurity levels to generate more hydrogen peroxide and subsequent ·OH radicals. The active species under UV were in the following order: h+ ≫ e- > ·OH, while it was vice versa for the Vis system with a well-balanced 50 wt% CuO/CNT catalyst that exhibited a similar performance. The kinetic study showed the transition of the kinetic order from the zeroth to the first order on increasing the PCA concentration under the Vis system and vice versa for the UV system. The Thiele modulus (ϕ) further confirmed that the effect of internal mass transfer was negligible under UV light. In contrast, the transition from mass transfer to kinetic control limitation was observed under the Vis system. The optimum PCA degradation predicted from the response surface analysis was 97.36% at the reaction pH of 7.3, catalyst dosage of 0.45 g L-1, and initial PCA concentration of 11.02 mg L-1. The condition obtained was fairly close to the forecasted value with an error of 0.26%.

13.
Membranes (Basel) ; 11(11)2021 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-34832039

RESUMEN

Hydrogen is a zero-carbon footprint energy source with high energy density that could be the basis of future energy systems. Membrane-based water electrolysis is one means by which to produce high-purity and sustainable hydrogen. It is important that the scientific community focus on developing electrolytic hydrogen systems which match available energy sources. In this review, various types of water splitting technologies, and membrane selection for electrolyzers, are discussed. We highlight the basic principles, recent studies, and achievements in membrane-based electrolysis for hydrogen production. Previously, the Nafion™ membrane was the gold standard for PEM electrolyzers, but today, cheaper and more effective membranes are favored. In this paper, CuCl-HCl electrolysis and its operating parameters are summarized. Additionally, a summary is presented of hydrogen production by water splitting, including a discussion of the advantages, disadvantages, and efficiencies of the relevant technologies. Nonetheless, the development of cost-effective and efficient hydrogen production technologies requires a significant amount of study, especially in terms of optimizing the operation parameters affecting the hydrogen output. Therefore, herein we address the challenges, prospects, and future trends in this field of research, and make critical suggestions regarding the implementation of comprehensive membrane-based electrolytic systems.

14.
Sci Rep ; 11(1): 3764, 2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33580110

RESUMEN

Two novel types of anion exchange membranes (AEMs) having imidazolium-type functionalised nanofibrous substrates were prepared using the facile and potentially scalable method. The membranes' precursors were prepared by graft copolymerization of vinylbenzyl chloride (VBC) onto syndiotactic polypropylene (syn-PP) and polyamide-66 (PA-66) nanofibrous networks followed by crosslinking with 1,8-octanediamine, thermal treatment and subsequent functionalisation of imidazolium groups. The obtained membranes displayed an ion exchange capacity (IEC) close to 1.9 mmol g-1 and ionic (OH-) conductivity as high as 130 mS cm-1 at 80 °C. This was coupled with a reasonable alkaline stability representing more than 70% of their original conductivity under accelerated degradation test in 1 M KOH at 80 °C for 360 h. The effect of ionomer binder on the performance of the membrane electrode assembly (MEA) in AEM fuel cell was evaluated with the optimum membrane. The MEA showed a power density of as high as 440 mW cm-2 at a current density is 910 mA cm-2 with diamine crosslinked quaternized polysulfone (DAPSF) binder at 80 °C with 90% humidified H2 and O2 gases. Such performance was 2.3 folds higher than the corresponding MEA performance with quaternary ammonium polysulfone (QAPS) binder at the same operating conditions. Overall, the newly developed membrane was found to possess not only an excellent combination of physico-chemical properties and a reasonable stability but also to have a facile preparation procedure and cheap ingredients making it a promising candidate for application in AEM fuel cell.

15.
Indian J Thorac Cardiovasc Surg ; 35(1): 36-40, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33060967

RESUMEN

INTRODUCTION: Chronic pleural empyema is usually a consequence of in adequate treatment of acute pleural empyema. The incidence of tubercular and post-intervention empyema has increased in underdeveloped or developing countries adding to economic burden on the society. We have performed a retrospective analysis on role of intervention in chronic empyema to improve respiratory functional outcomes. METHODS: We retrospectively reviewed data of 115 patients of chronic tubercular and parapneumonic empyema thoracis to evaluate change in functional outcome parameters based on their treatment modalities during follow-up in department of surgery, King George's Medical University, Lucknow, India. Accordingly, four groups were made-group 1 (tube thoracostomy), group 2 (decortication by video-assisted thoracoscopic surgery (VATS)), group 3 (decortication by open thoracotomy), and group 4 (window thoracostomy followed by thoracomyoplasty). RESULTS: Significant improvement was noted in forced expiratory volume in one second (FEV1)% and forced vital capacity (FVC)% in all groups. In spirometry, percent change in mean FEV1 from pre-intervention to post-intervention was increase of 55.4%, 38.3%, 47.2, and 59.21% in group 1, group 2, group 3, and group 4 respectively, and percent change in mean FVC from pre-intervention to post-intervention was increase of 53.30%, 38.11%, 51.23, and 54.21% in group 1, group 2, group 3, and group 4 respectively. CONCLUSION: Our study showed that a significant increase was observed in FVC and FEV1 from pre to post among all the groups. Comparable improvement of functional outcomes with non-operative intervention in properly selected patients can be achieved.

17.
Nanoscale ; 10(27): 13212-13222, 2018 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-29971298

RESUMEN

A novel polyoxometalate-based electrode was developed by incorporating phosphotungstic acid (PWA) in nylon-6,6 nanofiber, followed by carbonization. The developed PWA-carbon nanofiber (PWA-CNF) showed the characteristics of the dual-scale porosity of micro- and mesoporous substrate with surface area of around 684 m2 g-1. The compound exhibited excellent stability in vanadium electrolyte and battery cycling. Evaluation of electrocatalytic properties toward V2+/V3+ and VO2+/VO2+ redox couples indicated promising advantages in electron transfer kinetics and increasing energy efficiency, particularly for the VO2+/VO2+ couple. Moreover, the developed electrode exhibited substantially improved energy efficiency (14% higher than that of pristine carbon felt) in the single cell vanadium redox flow battery. This outstanding performance was attributed to high surface area and abundant oxygen-containing linkages in the developed electrode.

19.
BMJ Case Rep ; 2016: 10.1136/bcr-2016-214811, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-27084900

RESUMEN

Spontaneous prolapse of the sigmoid colon and evisceration of the small bowel through a rupture in the rectosigmoid is a rare presentation. We report a case of a 60-year-old man presenting with massive small bowel evisceration through a perforation in a prolapsed sigmoid colon. The patient had a 2-year history of rectal prolapse. He was also incontinent for flatus and liquid stool. There was no other significant medical history. After reduction of the small intestine, a large perforation was seen in the prolapsed sigmoid colon. The sigmoid colon was identified by presence of appendices epiploicae and taeniae coli. After initial resuscitation, an emergency laparotomy was performed. The perforated sigmoid colon was resected and a Hartmann's colostomy was created. This resulted in complete recovery. Reversal of the Hartmann's colostomy was performed after 6 weeks.


Asunto(s)
Colon Sigmoide , Perforación Intestinal/complicaciones , Intestino Delgado , Prolapso Rectal/complicaciones , Enfermedades del Sigmoide/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Rotura Espontánea/etiología
20.
ACS Appl Mater Interfaces ; 7(31): 17008-15, 2015 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-26196374

RESUMEN

High level of phosphotungstic acid (PWA) was self-immobilized on electrospun nylon nanofiberous sheet to fabricate highly selective methanol barrier layer for sandwich structured proton conducting membranes. Simple tuning for the assembly conditions of central layer and thickness of outer Nafion layers allowed obtaining different composite membranes with superior methanol barrier properties (namely, P=3.59×10(-8) cm2 s(-1)) coupled with proton conductivities reaching 58.6 mS cm(-1) at 30 °C. Comparable activation energy for proton transport and more than 20 times higher selectivity than Nafion 115 confirm the effectiveness of the central layer and resulting membranes for application in direct methanol fuel cells (DMFCs). When tested in DMFC single cell, the performance of hybrid membrane was far better than Nafion 115 especially at higher methanol concentrations.

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