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1.
Chemistry ; 29(48): e202301261, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37098116

RESUMEN

Liesegang patterns that develop as a result of reaction-diffusion can simultaneously form products with slightly different sizes spatially separated in a single medium. We show here a reaction-diffusion method using a dormant reagent (citrate) for developing Liesegang patterns of cobalt hexacyanoferrate Prussian Blue analog (PBA) particle libraries. This method slows the precipitation reaction and produces different-sized particles in a gel medium at different locations. The gel-embedded particles are still catalytically active. Finally, the applicability of the new method to other PBAs and 2D systems is presented. The method proves promising for obtaining similar inorganic framework libraries with catalytic abilities.

2.
Opt Express ; 30(6): 8794-8803, 2022 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-35299324

RESUMEN

Terahertz radiation as an upcoming carrier frequency for next-generation wireless communication systems has great potential to enable ultra-high-capacity transmissions with several tens of gigahertz bandwidths. Nevertheless, dispersion is one of the main impairments in achieving a higher bit rate. Here, we experimentally demonstrate a compact terahertz dispersion compensator based on subwavelength gratings. The gratings are fabricated from the low-loss cyclic olefin copolymer exploiting micro-machining fabrication techniques. With the strong index modulation introduced in the subwavelength grating, the high negative group velocity dispersion of -188 (-88) ps/mm/THz is achieved at 0.15 THz for x-polarization (y-polarization), i.e., 7.5 times increase compared to the state-of-the-art reported to date for terahertz. Such high negative dispersion is realized in a grating of 43 mm length. The asymmetric cross-section and periodic-structural modulation along propagation direction lead to considerable birefringence that maintains and filters two orthogonal polarization states, respectively. These polymer-based birefringent gratings can be integrated into terahertz communication systems for dispersion compensation of both long-haul wireless links and waveguide-based interconnect links.

3.
Plant J ; 79(6): 941-50, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24942184

RESUMEN

Drought is a major abiotic stress that affects the development and growth of most plants, and limits crop yield worldwide. Although the response of plants to drought has been well documented, much less is known about how plants respond to the water recovery process, namely rehydration. Here, we describe the spatio-temporal response of plant reproductive organs to rehydration using rose flowers as an experimental system. We found that rehydration triggered rapid and transient ethylene production in the gynoecia. This ethylene burst serves as a signal to ensure water recovery in flowers, and promotes flower opening by influencing the expression of a set of rehydration-responsive genes. An in-gel kinase assay suggested that the rehydration-induced ethylene burst resulted from transient accumulation of RhACS1/2 proteins in gynoecia. Meanwhile, RhMPK6, a rose homolog of Arabidopsis thaliana MPK6, is rapidly activated by rehydration within 0.5 h. Furthermore, RhMPK6 was able to phosphorylate RhACS1 but not RhACS2 in vitro. Application of the kinase inhibitor K252a suppressed RhACS1 accumulation and rehydration-induced ethylene production in gynoecia, and the protein phosphatase inhibitor okadaic acid had the opposite effect, confirming that accumulation of RhACS1 was phosphorylation-dependent. Finally, silencing of RhMPK6 significantly reduced ethylene production in gynoecia when flowers were subjected to rehydration. Taken together, our results suggest that temporal- and spatial-specific activation of an RhMPK6-RhACS1 cascade is responsible for rehydration-induced ethylene production in gynoecia, and that the resulting ethylene-mediated signaling pathway is a key factor in flower rehydration.


Asunto(s)
Flores/enzimología , Regulación de la Expresión Génica de las Plantas , Liasas/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Rosa/enzimología , Agua/fisiología , Carbazoles/farmacología , Sequías , Inhibidores Enzimáticos/farmacología , Etilenos/metabolismo , Flores/genética , Flores/fisiología , Silenciador del Gen , Alcaloides Indólicos/farmacología , Liasas/metabolismo , Sistema de Señalización de MAP Quinasas , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Datos de Secuencia Molecular , Especificidad de Órganos , Fosforilación , Filogenia , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Proteínas Recombinantes , Rosa/genética , Rosa/fisiología , Análisis de Secuencia de ADN , Factores de Tiempo
4.
Talanta ; 277: 126374, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38878514

RESUMEN

Reactive oxygen species (ROS), reactive sulfur species (RSS), metal ions, and nitrogen species (RNS) play important roles in a variety of biological processes, such as a signal transduction, inflammation, and neurodegenerative damage. These species, while essential for certain functions, can also induce stress-related diseases. The interrelation between ROS, RSS, Metal ions and RNS underscores the importance of quantifying their concentrations in live cells, tissues, and organisms. The review emphasizes the use of small-molecule-based fluorescent/chemodosimeter probes to effectively measure and map the species' distribution with high temporal and spatial precision, paying particular attention to in vitro and in vivo environments. These probes are recognized as valuable tools contributing to breakthroughs in modern redox biology. The review specifically addresses the relationship of HOCl/ClO‾ (hypochlorous acid/Hypochlorite) with other reactive species. (Dual sensing probes).


Asunto(s)
Colorantes Fluorescentes , Ácido Hipocloroso , Especies Reactivas de Oxígeno , Ácido Hipocloroso/análisis , Ácido Hipocloroso/química , Colorantes Fluorescentes/química , Humanos , Animales , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/análisis , Especies de Nitrógeno Reactivo/análisis , Especies de Nitrógeno Reactivo/química , Especies de Nitrógeno Reactivo/metabolismo
5.
PeerJ Comput Sci ; 10: e1979, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38855242

RESUMEN

This article uses the Aczel-Alsina t-norm and t-conorm to make several new linguistic interval-valued intuitionistic fuzzy aggregation operators. First, we devised some rules for how linguistic interval-valued intuitionistic fuzzy numbers should work. Then, using these rules as a guide, we created a set of operators, such as linguistic interval-valued intuitionistic fuzzy Aczel-Alsina weighted averaging (LIVIFAAWA) operator, linguistic interval-valued intuitionistic fuzzy Aczel-Alsina weighted geometric (LIVIFAAWG) operator, linguistic interval-valued intuitionistic fuzzy Aczel-Alsina ordered weighted averaging (LIVIFAAOWA) operator, linguistic interval-valued intuitionistic fuzzy Aczel-Alsina ordered weighted geometric (LIVIFAAOWG) operator, linguistic interval-valued intuitionistic fuzzy Aczel-Alsina hybrid weighted averaging (LIVIFAAHWA) operator and linguistic interval-valued intuitionistic fuzzy Aczel-Alsina hybrid weighted geometric (LIVIFAAHWG) operators are created. Several desirable qualities of the newly created operators are thoroughly studied. Moreover, a multi-criteria group decision-making (MCGDM) method is proposed based on the developed operators. The proposed operators are then applied to real-world decision-making situations to demonstrate their applicability and validity to the reader. Finally, the suggested model is contrasted with the currently employed method of operation.

6.
PeerJ Comput Sci ; 10: e1938, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38660182

RESUMEN

Deep learning approaches are generally complex, requiring extensive computational resources and having high time complexity. Transfer learning is a state-of-the-art approach to reducing the requirements of high computational resources by using pre-trained models without compromising accuracy and performance. In conventional studies, pre-trained models are trained on datasets from different but similar domains with many domain-specific features. The computational requirements of transfer learning are directly dependent on the number of features that include the domain-specific and the generic features. This article investigates the prospects of reducing the computational requirements of the transfer learning models by discarding domain-specific features from a pre-trained model. The approach is applied to breast cancer detection using the dataset curated breast imaging subset of the digital database for screening mammography and various performance metrics such as precision, accuracy, recall, F1-score, and computational requirements. It is seen that discarding the domain-specific features to a specific limit provides significant performance improvements as well as minimizes the computational requirements in terms of training time (reduced by approx. 12%), processor utilization (reduced approx. 25%), and memory usage (reduced approx. 22%). The proposed transfer learning strategy increases accuracy (approx. 7%) and offloads computational complexity expeditiously.

7.
Int Immunopharmacol ; 126: 111259, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37992446

RESUMEN

Multiple studies in the literature have demonstrated that synthetic compounds containing heterocyclic rings possess a reparative potential against acute and chronic inflammation. In the present study, two novel thiosemicarbazone derivatives based on l-ethyl-6-(thiophen-2-yl)indoline-2,3-dione with different phenyl substituted thiosemicarbazides were synthesized by condensation reaction and the structures of proposed target compounds (KP-2 and KP-5) were confirmed by UV-VIS, FTIR, 1H-NMR and 13C-NMR. In-vitro anti-inflammatory behavior of KP-2 and KP-5 was confirmed by bovine serum albumin (BSA) and ovine serum albumin (OSA) analysis. Acute and chronic anti-inflammatory potential of synthesized compounds were evaluated by using carrageenan and complete Freund's adjuvant (CFA) as inflammation-inducing agents, respectively. Inhibition of pro-inflammatory mediators and prevention of protein denaturation owing to synchronization of more electronegative flouro-groups substituted on phenyl rings along with heterocyclic indoline ring provides anti-inflammatory effects and are corroborated by radiological, histopathological analysis. Additional support was provided through density functional theory (DFT) and molecular docking. KP-5 exhibited excellent lead-likeness based on its physicochemical parameters, making it a viable drug candidate. The synthesized compounds also showed promising ADMET properties, enhancing their potential as therapeutic agents. These findings emphasize the pivotal role of new compounds for drug design and development.


Asunto(s)
Tiosemicarbazonas , Animales , Ovinos , Humanos , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad , Tiosemicarbazonas/farmacología , Tiosemicarbazonas/uso terapéutico , Antiinflamatorios/uso terapéutico , Inflamación/tratamiento farmacológico , Carragenina , Estructura Molecular , Edema/inducido químicamente , Edema/tratamiento farmacológico , Inhibidores de la Ciclooxigenasa 2/farmacología
9.
Eur J Gastroenterol Hepatol ; 34(1): 11-17, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33405425

RESUMEN

BACKGROUND: Patients with gastrointestinal angiodysplasia (GIA)-related bleeding are at high risk for readmissions, resulting in significant morbidity and an economic burden on the healthcare system. AIM: The aim of the study was to determine the 30-day readmission rate with reasons, predictors, and costs associated with GIA-related bleeding in the USA. METHODS: We queried the National Readmission Database to identify patients hospitalized with GIA-related bleeding in the year 2016 using the International Classification of Diseases, Tenth Revision (ICD-10) codes. Primary outcomes included the 30-day readmission rate, and secondary outcomes were in-hospital mortality and resource utilization for index and re-hospitalizations. We also performed univariate and multivariate cox regression analysis to identify predictors of readmissions. RESULTS: A total of 25 079 index hospitalizations for GIA-related bleeding were identified in 2016. Out of these, 5047 (20.34%) patients got readmitted within the next 30 days. The most common diagnosis associated with readmissions were related to recurrent gastrointestinal bleeding. Readmissions compared to index hospitalization has significantly higher length of stay (5.38 vs. 5.11 days, P = 0.03), but mean hospitalization charges ($52 114 vs. $49 691, P = 0.11) and mean total hospitalization costs ($12 870 vs. $12 405, P = 0.16) were similar. Patients with multiple co-morbidities, length of stay >5 days, and end-stage renal disease were found to be independent predictors for 30-day readmissions. CONCLUSION: Our study shows that one in five patients hospitalized with GIA-related bleeding was readmitted within 30 days of index hospitalization, placing a heavy economic burden on the healthcare system. Further research identifying strategies to reduce readmissions in these patients is needed.


Asunto(s)
Angiodisplasia , Enfermedades del Colon , Angiodisplasia/complicaciones , Angiodisplasia/diagnóstico , Angiodisplasia/terapia , Bases de Datos Factuales , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/terapia , Hospitalización , Humanos , Readmisión del Paciente , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos/epidemiología
10.
Cancer Manag Res ; 14: 1323-1329, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35392356

RESUMEN

Breast cancer (BC) is the most common malignancy affecting women, and its incidence in younger women is rising worldwide. Early-onset of BC is a multi-step process involving various biological aggressive tumors such as triple negative and human epidermal growth factor 2 (HER2)-positive cancers. BC prevention is still arduous across the globe. A series of observational studies have established a conclusive non-genetic clinical link between hypertension (HTN) and the development of invasive BC. Those clinical associations have driven a pharmacological seek to use the anti-hypertension (AHTN) drugs as an effective adjunctive in BC therapy. The use of AHTN, especially beta-blockers and thiazides, has been recognized as a potent anti-tumor drug to mitigate BC progression, reduce the side effects of cancer treatment, and stop the reoccurrence of cancer in the survivors. Considering the dire need to disseminate the research on how AHTN drugs can be opted as the effective adjunctive therapy to cure the BC, the current review aimed to provide an update on novel understandings on association and mechanisms of AHTN-drugs against BC as an additional cancer therapy.

11.
ACS Omega ; 7(27): 23643-23652, 2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35847279

RESUMEN

Simvastatin (SIM) is a diet drug to treat high lipid levels in the blood. It has the drawback of being metabolized in humans' gastrointestinal tract (GIT) when taken in an oral dosage form. To enhance the role of SIM in treating hyperlipidemias and bypassing its metabolism in GIT, a biodegradable nanocarrier as a SIM-loaded lipid emulsion nanoparticle via the solvent injection method was designed. Cholesterol acts as a lipid core, and Tween 80 was utilized to stabilize the core. The optimized nanoformulation was characterized for its particle diameter, zeta potential, surface morphology, entrapment efficiency, crystallinity, and molecular interaction. Furthermore, the transdermal hydrogel was characterized by physical appearance, rheology, pH, and spreadability. In vitro assays were executed to gauge the potential of LENPs and olive oil for transdermal delivery. The mean particle size and zeta potential of the optimized nanoparticles were 174 nm and -22.5 mV 0.127, respectively. Crystallinity studies and Fourier transform infrared analyses revealed no molecular interactions. Hydrogels showed a sustained release compared to SIM-loaded LENPs that can be proposed as a better delivery system for SIM. We encourage further investigations to explore the effect of reported formulations for transdermal delivery by in vivo experiments.

12.
ACS Omega ; 7(36): 32410-32417, 2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36120013

RESUMEN

Graphene oxide (GO)-based membranes with tunable microstructure and controlled nanochannels have attracted an increasing interest for various applications in wastewater treatment, desalination, gas separation, organic nanofiltration, etc. However, they showed limited use in water desalination due to their lower stability and separation efficiency. In this work, a class of two-dimensional (2D) GO lamellar membranes have been prepared with controlled pores for efficient and fast separation of ions and dye molecules. The GO membranes are fucntionalized with a star-like 6-armed poly(ethylene oxide) using the simple amidation route under mild conditions. The as-prepared covalently cross-linked networks are chemically steady in aqueous medium and show remarkable selectivity (∼100%) for several probe molecules and 10-100 higher permeance than those of the reported GO-based membranes. Further, such membranes are also used for salt separation and show more than 80% rejection for Pb2+ and Ni2+ salts. Moreover, a 1360 nm-thick membrane shows >99% rejection for NaCl with a good water permeance of up to 120 L m-2 h-1 bar-1. Additionally, these membranes are stable for more than 20 days under different conditions.

13.
J Adv Res ; 36: 223-247, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35127174

RESUMEN

Background: Skin cancer has been the leading type of cancer worldwide. Melanoma and non-melanoma skin cancers are now the most common types of skin cancer that have been reached to epidemic proportion. Based on the rapid prevalence of skin cancers, and lack of efficient drug delivery systems, it is essential to surge the possible ways to prevent or cure the disease. Aim of review: Although surgical modalities and therapies have been made great progress in recent years, however, there is still an urgent need to alleviate its increased burden. Hence, understanding the precise pathophysiological signaling mechanisms and all other factors of such skin insults will be beneficial for the development of more efficient therapies. Key scientific concepts of review: In this review, we explained new understandings about onset and development of skin cancer and described its management via polymeric micro/nano carriers-based therapies, highlighting the current key bottlenecks and future prospective in this field. In therapeutic drug/gene delivery approaches, polymeric carriers-based system is the most promising strategy. This review discusses that how polymers have successfully been exploited for development of micro/nanosized systems for efficient delivery of anticancer genes and drugs overcoming all the barriers and limitations associated with available conventional therapies. In addition to drug/gene delivery, intelligent polymeric nanocarriers platforms have also been established for combination anticancer therapies including photodynamic and photothermal, and for theranostic applications. This portfolio of latest approaches could promote the blooming growth of research and their clinical availability.


Asunto(s)
Nanoestructuras , Neoplasias Cutáneas , Biología , Sistemas de Liberación de Medicamentos , Humanos , Nanoestructuras/química , Polietilenglicoles/química , Polímeros/química , Neoplasias Cutáneas/tratamiento farmacológico
14.
Eur J Gastroenterol Hepatol ; 34(5): 478-487, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35170533

RESUMEN

Benign biliary strictures (BBS) are usually treated with endoscopic retrograde cholangiopancreatography (ERCP) with the placement of multiple plastic stents (MPS) or a covered self-expandable metal stent (CSEMS). In this meta-analysis, we compared the efficacy and safety of MPS and CSEMS in the management of BBS. We reviewed several databases from inception to 28 April 2021 to identify RCTs that compared MPS with CSEMS in the management of BBS. Our outcomes of interest were stricture resolution, stricture recurrence, adverse events, stent migration and mean number of ERCPs to achieve stricture resolution. Data were analyzed using a random-effects model. We included eight RCTs with 524 patients. We found no significant difference in the rate of stricture resolution (risk ratio, 1.02; 95% CI, 0.96-1.10), stricture recurrence (risk ratio, 1.68; 95% CI, 0.72-3.88) or adverse events (risk ratio, 1.17; 95% CI, 0.73-1.87) between groups. Mean number of ERCPs was significantly lower in the CSEMS group (SMD, -1.99; 95% CI, -3.35 to -0.64). The rate of stent migration was significantly higher in the CSEMS group. CSEMS are comparable in efficacy and safety to MPS in the management of BBS but require fewer ERCPs to achieve stricture resolution.


Asunto(s)
Colestasis , Stents Metálicos Autoexpandibles , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Colestasis/diagnóstico por imagen , Colestasis/etiología , Colestasis/cirugía , Constricción Patológica , Humanos , Metales , Plásticos , Ensayos Clínicos Controlados Aleatorios como Asunto , Stents Metálicos Autoexpandibles/efectos adversos , Stents/efectos adversos , Resultado del Tratamiento
15.
Cureus ; 13(6): e16029, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34336516

RESUMEN

Introduction Non-alcoholic fatty liver disease (NALFD) has become one of the most pervasive causes of hepatic pathology. Because of its marked association with metabolic syndrome, type II diabetes and cardiovascular disease, NAFLD has gained substantial focus recently. Its prevalence and incidence are on the rise in Pakistan. However, due to its indolent and mostly asymptomatic course, NAFLD is often overlooked. This reckless behavior towards a potentially deadly disease is influenced most notably by disinformation or flawed perception, although there are a number of other complex socioeconomic components to this as well. With respect to NAFLD, the gap between disease understanding and steps for management is growing in the Pakistani society. With this study, we hoped and aimed to evaluate just how far and wide these shortcomings were found and how was NAFLD perceived in the local populace via a self-administered survey. Methods This was a cross-sectional observational cohort study undertaken at the Department of Gastroenterology, Jinnah Postgraduate Medical Centre, and Medical Unit II, Dow University of Health Sciences, Ojha Campus, Karachi, Pakistan. All patients ≥18 years with a diagnosis of NAFLD were included in the study. NAFLD was diagnosed on the basis of sonographic evidence. All ultrasounds were done by a senior expert radiologist with at least 10 years of postgraduate experience. Ultrasounds were performed twice in all patients to rule out human error and bias. Perceptions regarding the knowledge of NAFLD were assessed using a self-administered survey questionnaire. Results The female-to-male ratio in our cohort was 3:1. The mean age and body mass index (BMI) recorded were 39.85 ± 9.79 years and 31.21 ± 3.6 kg/m2, respectively. Sixty participants (26.4%) knew about their disease (NAFLD) while only 36 (15.9%) knew what NAFLD was and only 33 (14.5%) participants knew about the cardiovascular risk associated with it. Nearly two-thirds of the patients considered themselves overweight, while 180 (79.3%) of them were willing to lose weight. However, just about half of the cohort admitted the need for improved eating habits and increased physical activity/exercise in their daily lives. Fifty-seven (25.1%) patients admitted to using alternative or quack medications and only 45 (19.8%) patients considered them harmful. Conclusions Patients harboring NAFLD have little to no knowledge about the disease and its nature or the fact that they are suffering from it despite being diagnosed clinically. Furthermore, while the general populace is willing to accept being overweight and having unhealthy eating habits, their willingness in initiating real-life practical steps to manage NAFLD is lacking.

16.
Polymers (Basel) ; 13(3)2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33499265

RESUMEN

Flexible substrates have become essential in order to provide increased flexibility in wearable sensors, including polymers, plastic, paper, textiles and fabrics. This study is to comprehensively summarize the bending capabilities of flexible polymer substrate for general Internet of Things (IoTs) applications. The basic premise is to investigate the flexibility and bending ability of polymer materials as well as their tendency to withstand deformation. We start by providing a chronological order of flexible materials which have been used during the last few decades. In the future, the IoT is expected to support a diverse set of technologies to enable new applications through wireless connectivity. For wearable IoTs, flexibility and bending capabilities of materials are required. This paper provides an overview of some abundantly used polymer substrates and compares their physical, electrical and mechanical properties. It also studies the bending effects on the radiation performance of antenna designs that use polymer substrates. Moreover, we explore a selection of flexible materials for flexible antennas in IoT applications, namely Polyimides (PI), Polyethylene Terephthalate (PET), Polydimethylsiloxane (PDMS), Polytetrafluoroethylene (PTFE), Rogers RT/Duroid and Liquid Crystal Polymer (LCP). The study includes a complete analysis of bending and folding effects on the radiation characteristics such as S-parameters, resonant frequency deviation and the impedance mismatch with feedline of the flexible polymer substrate microstrip antennas. These flexible polymer substrates are useful for future wearable devices and general IoT applications.

17.
iScience ; 24(6): 102539, 2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34142047

RESUMEN

The high variability and intermittency of wind and solar farms raise questions of how to operate electrolyzers reliably, economically, and sustainably using predominantly or exclusively variable renewables. To address these questions, we develop a comprehensive cost framework that extends to include factors such as performance degradation, efficiency, financing rates, and indirect costs to assess the economics of 10 MW scale alkaline and proton-exchange membrane electrolyzers to generate hydrogen. Our scenario analysis explores a range of operational configurations, considering (i) current and projected wholesale electricity market data from the Australian National Electricity Market, (ii) existing solar/wind farm generation curves, and (iii) electrolyzer capital costs/performance to determine costs of H2 production in the near (2020-2040) and long term (2030-2050). Furthermore, we analyze dedicated off-grid integrated electrolyzer plants as an alternate operating scenario, suggesting oversizing renewable nameplate capacity with respect to the electrolyzer to enhance operational capacity factors and achieving more economical electrolyzer operation.

18.
Cureus ; 13(7): e16558, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34430162

RESUMEN

Introduction Hepatitis B virus (HBV) is the leading cause of cirrhosis in the developing world. Despite the development of effective vaccine(s) and direct-acting antivirals (DAAs) such as tenofovir and entecavir, the eradication of chronic HBV remains a distant dream in endemic regions. Factors such as treatment naivety, longer duration of disease, late diagnosis, family history of liver disorders and hepatocellular carcinoma, fatty liver disease, multiple comorbidities, alcoholism, use of tobacco products, noncompliance to drugs, and loss to follow-up all contribute to disease progression and development of complications. In order to promote a better understanding of the treatment initiation, duration, and eventual outcomes, the European Association for the Study of the Liver (EASL) updated its guidelines in 2017 and introduced a new staging system for chronic HBV. Since these guidelines are relatively recent, data regarding the new staging is virtually absent in local/regional settings. Moreover, it has been observed that patients presenting to secondary care setups at major urban centers have disease characteristics quite distinct from those of their rural counterparts or patients presenting to tertiary care setups, even in the same cities. Additionally, there is scarce published data with regard to this aspect. With this study, we hope to make progress on all of those fronts. Objective We aimed to evaluate the demographics, biochemical characteristics, and phases of chronic HBV at the secondary care level. Methods This was a retrospective observational cohort conducted at the Sindh Government Hospital, Liaquatabad from January to December 2020. Patients of either gender who were aged ≥12 years, and diagnosed as a case of chronic HBV were eligible to be enrolled in the study. Only treatment-naive patients were enrolled in the study. Demographics, biochemical characteristics, and phases of HBV (in light of the updated guidelines issued by EASL in 2017 with respect to HBV) were recorded and analyzed. Patient confidentiality was ensured at all times. Results A total of 102 patients were enrolled in the study. The mean age of our cohort was 34.31 ±12.42 years, and the male-to-female ratio was 3:2. All referrals were made from within the city district. Housewives and laborers made up the majority of our patients. The mean alanine transaminase (ALT) levels were 39.83 ±21.33 IU/L; otherwise, the biochemical profile of the patients was unremarkable. Phase III was the most frequently recorded stage of chronic HBV; 41 (40.19%) of the patients were diagnosed with it. However, nearly half of the patients had chronic active hepatitis (phases II and IV). Only a single case each of hepatitis Delta virus and decompensated liver disease (DCLD) was recorded. Conclusions All patients of chronic HBV presenting at the secondary care level were referred locally, were relatively older, and exhibited a higher frequency of chronic active hepatitis (phases II and IV). This corresponded to borderline elevations of ALT. But the remainder of the biochemical profile was largely unremarkable due to the very low prevalence of cirrhosis among these patients.

19.
Cureus ; 13(5): e14828, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-34104581

RESUMEN

Introduction Asthma is a clinical syndrome characterized by reversible and recurrent airway obstruction leading to the symptoms of wheezing, cough, shortness of breath, fatigue, and respiratory distress. It is one of the most common lung pathologies worldwide. Its incidence is on the rise in Pakistan, which may be due to overt environmental pollution or improving screening protocols. Irrespective more and more patients are now being diagnosed as cases of asthma and this has led to renewed interest in research for the subject locally. Vitamin D plays a key component of the immune system and its deficiency has been associated with diseases, such as inflammatory bowel disease, celiac disease, rheumatoid arthritis, depression, sepsis, and coronavirus disease 2019 (COVID-19) pneumonia. The role of vitamin D in exacerbation, prevention, causation, and treatment of asthma is still up for debate. However, as more data emerges, it is becoming evident that vitamin D in one way or another is linked to outcomes in asthma. Especially the deficiency of vitamin D in asthma and its supplementation has garnered great attention in scientific trials. Our research is just one small step in this direction. This study aims to evaluate the frequency of vitamin D deficiency in patients with asthma. Methods This was a retrospective cross-sectional cohort conducted at the Department of Medicine of Abbasi Shaheed Hospital Karachi (ASHK) during March 2019 to August 2019. Patients of either gender aged ≥18 years that were diagnosed with cases of asthma were eligible to be included in the study. Asthma was defined in accordance with the latest guidelines issued by the Pakistan Chest Society. A vitamin D level of <20 ng/dl was considered deficient. Patient confidentiality was made certain.  Results A total of 97 (62.98%) of the 154 patients included in the study had <20 ng/ml of vitamin D level. The mean vitamin D level recorded in this study was 15.34±4.21 ng/dl. The male-to-female ratio was 1:5. The mean age of our cohort was 42.78±4.56 years. The mean duration of disease, i.e., asthma was 6.7±3.68 years. Both the age of the patients and duration of the disease were found to be statistically significant with respect to vitamin D levels in asthmatics. Conclusions The frequency of vitamin D deficiency is very high in patients with asthma. These suboptimal levels are significantly influenced by the age of the patient and the duration of the disease.

20.
Artículo en Inglés | MEDLINE | ID: mdl-33442283

RESUMEN

To look superior and acceptable in society, people from all over the world use various types of cosmetic products to enhance or alter their facial appearance and body texture. In recent times, an exponential surge in cosmetic use has been observed in Pakistan, and hence spending money on personal-care products is high. However, there are many reported facts about high loads of lead, mercury, copper, and others hazardous and cancerous elements in local Pakistani cosmetic brands. Consumers of these brands are at high risk of many clinical issues, including cancer. As such, it is a necessity to make people aware of the devastating harmful effects related to cosmetic use. The aim of this study was to provide information for stakeholders and raise awareness in the general public about the use of these local unauthorized personal-care cosmetic products, along with government strategies to stop this cosmetic blight on human health.

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