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1.
Int J Biol Macromol ; : 131762, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38657925

RESUMO

The present investigation describes the development of a novel Chitosan/Polyvinyl Alcohol/Montmorillonite Clay (CS/PVA/MMT) scaffold by adopting an electrospinning method, and their biocompatibility was evaluated in vitro with L929 fibroblast cell line to ascertain its use in wound healing applications. The fabricated scaffold was characterized using analytical techniques. FT-IR measurement exhibited the existence of relevant functional groups and XRD implies scaffolds' amorphous nature. The scaffold's morphology and pore diameter were assessed using TEM and SEM. The pore diameter of the as-prepared scaffold was approximately 125 nm. The antimicrobial assay of the scaffold was evaluated against selected pathogens which demonstrated higher antimicrobial efficacy. The scavenging activity tested using the DPPH assay showed remarkable scavenging capability. The wound healing properties were tested through the Cytotoxicity assay conducted on the L929 assay which proved the scaffold to be a suitable material for cell proliferation. Also, a Molecular docking investigation was carried out for CS/PVA/MMT ligand using human neutrophil elastase (HNE) 1H1B protein as a receptor in the CB-Dock server. Studies conducted in silico revealed strong interaction and high binding energy ratings of CS/PVA/MMT ligand with key residues of human neutrophil elastase (HNE) 1H1B proteins that help in tissue regeneration activity.

2.
Environ Geochem Health ; 46(5): 172, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592578

RESUMO

Advancement in bioinspired alloy nanomaterials has a crucial impact on fuel cell applications. Here, we report the synthesis of PtPd alloy nanoclusters via the hydrothermal method using Piper longum extract, representing a novel and environmentally friendly approach. Physicochemical characteristics of the synthesized nanoclusters were investigated using various instrumentation techniques, including X-ray photoelectron spectroscopy, X-ray diffraction, and High-Resolution Transmission electron microscopy. The electrocatalytic activity of the biogenic PtPd nanoclusters towards the oxidation of formic acid and methanol was evaluated chronoamperometry and cyclic voltammetry studies. The surface area of the electrocatalyst was determined to be 36.6 m2g-1 by Electrochemical Surface Area (ECSA) analysis. The biologically inspired PtPd alloy nanoclusters exhibited significantly higher electrocatalytic activity compared to commercial Pt/C, with specific current responses of 0.24 mA cm - 2 and 0.17 mA cm - 2 at synthesis temperatures of 180 °C and 200 °C, respectively, representing approximately four times higher oxidation current after 120 min. This innovative synthesis approach offers a promising pathway for the development of PtPd alloy nanoclusters with enhanced electrocatalytic activity, thereby advancing fuel cell technology towards a sustainable energy solution.


Assuntos
Formiatos , Metanol , Piper , Ligas , Extratos Vegetais
3.
Environ Geochem Health ; 46(4): 122, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483653

RESUMO

This study aims to explore the concentrations of Se and Hg in shellfish along the Gulf of Mannar (GoM) coast (Southeast India) and to estimate related risks and risk-based consumption limits for children, pregnant women, and adults. Se concentrations in shrimp, crab, and cephalopods ranged from 0.256 to 0.275 mg kg-1, 0.182 to 0.553 mg kg-1, and 0.176 to 0.255 mg kg-1, respectively, whereas Hg concentrations differed from 0.009 to 0.014 mg kg-1, 0.022 to 0.042 mg kg-1 and 0.011 to 0.024 mg kg-1, respectively. Se and Hg content in bamboo shark (C. griseum) was 0.242 mg kg-1 and 0.082 mg kg-1, respectively. The lowest and highest Se concentrations were found in C. indicus (0.176 mg kg-1) and C. natator (0.553 mg kg-1), while Hg was found high in C. griseum (0.082 mg kg-1) and low in P. vannamei (0.009 mg kg-1). Se shellfishes were found in the following order: crabs > shrimp > shark > cephalopods, while that of Hg were shark > crabs > cephalopods > shrimp. Se in shellfish was negatively correlated with trophic level (TL) and size (length and weight), whereas Hg was positively correlated with TL and size. Hg concentrations in shellfish were below the maximum residual limits (MRL) of 0.5 mg kg-1 for crustaceans and cephalopods set by FSSAI, 0.5 mg kg-1 for crustaceans and 1.0 mg kg-1 for cephalopods and sharks prescribed by the European Commission (EC/1881/2006). Se risk-benefit analysis, the AI (actual intake):RDI (recommended daily intake) ratio was > 100%, and the AI:UL (upper limit) ratio was < 100%, indicating that all shellfish have sufficient level of Se to meet daily requirements without exceeding the upper limit (UL). The target hazard quotient (THQ < 1) and hazard index (HI < 1) imply that the consumption of shellfish has no non-carcinogenic health impacts for all age groups. However, despite variations among the examined shellfish, it was consistently observed that they all exhibited a Se:Hg molar ratio > 1. This finding implies that the consumption of shellfish is generally safe in terms of Hg content. The health benefit indexes, Se-HBV and HBVse, consistently showed high positive values across all shellfish, further supporting the protective influence of Se against Hg toxicity and reinforcing the overall safety of shellfish consumption. Enhancing comprehension of food safety analysis, it is crucial to recognize that the elevated Se:Hg ratio in shellfish may be attributed to regular selenoprotein synthesis and the mitigation of Hg toxicity by substituting Se bound to Hg.


Assuntos
Mercúrio , Selênio , Poluentes Químicos da Água , Gravidez , Animais , Criança , Adulto , Feminino , Humanos , Mercúrio/análise , Selênio/análise , Monitoramento Biológico , Peixes/metabolismo , Frutos do Mar/análise , Crustáceos , Medição de Risco , Poluentes Químicos da Água/análise
4.
Environ Geochem Health ; 46(3): 110, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38460044

RESUMO

The primary intent of the research is to comprehensively assess the environmental benefits and cost dynamics associated with the adsorption process of CS-RHA (Copper Slag and Rice Husk Ash) to produce a novel geopolymer adsorbent material for application in wastewater treatment. The geopolymer forms a polyiron sialate network under alkali activation by dissolving fayalite, and aluminium silicate to ferro-ferri silicate hydrate gel. The mechanical strength, leaching characteristics, and microstructure of the geopolymer were determined using XRD and FTIR, and magnetic properties by VSM as well surface properties were derived from BET surface area and zeta potential. Recognizing the critical role of sodium iron silicate hydrate (NFS) in the sorption of methylene blue (MB) dyestuff, batch experiments were carried out using different adsorbents. The results indicated that the dye removal efficiency increased from 60% in control samples (FS) to 98% for the blend (FS1) under different pH values. The data was found to fit with the nonlinear form of Freundlich isotherm and follow pseudo-second-order kinetics. The active adsorption sites were deduced as -O-Fe-O-Si-O-Na and Si-OH groups. The addition of RHA increases the adsorption capacity of the geopolymer in a short time through chemical adsorption. The significant negative surface charge promotes MB adsorption via improved electrostatic attraction. The spent adsorbents were recovered through magnetic separation with a retrieval rate of 80-85% and active sites were rejuvenated by calcination. Consequently, waste copper slag emerges as a promising adsorbent with minimum potential ecological risk and high effective recycling capacity.


Assuntos
Cobre , Poluentes Químicos da Água , Biomassa , Ácido Silícico , Reciclagem , Adsorção , Azul de Metileno/química , Cinética , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química
5.
Chemosphere ; 349: 140860, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38052312

RESUMO

Phenanthrene is a persistent organic pollutant released by numerous industries. The purpose of the study is to construct a batch reactor for phenanthrene degradation using a bimetallic (BM) ZnS-SnS nanoparticle as a photocatalyst. ZnS-SnS BM NPs were used as a photocatalyst, employed from precursors Zinc acetate dihydrate and tin (II) chloride dihydrate, with crystalline cubic-shaped particle sizes. ZnS-SnS BM NPs were utilized in batch adsorption assays to assess the impact of phenanthrene degradation parameters on various PAHs (Polycyclic aromatic hydrocarbons) concentrations, pH levels, and irradiation sources. Adsorption kinetic and isotherm tests revealed that the pseudo-first order kinetic model, pseudo-second order kinetic model, and Langmuir isotherm model all fit effectively with the effective phenanthrene degradation using ZnS-SnS BM NPs. The degraded product were analyzed for GC-MS, revealing that organic pollutant phenanthrene was converted into harmless by-products like n-hexadecenoic acid, oleic acid, and octadecanoic acid. The toxicity of phenanthrene was observed to decrease with an increase in ZnS-SnS BM NPs concentration. ZnS-SnS BM NP concentration of 150 µg/mL, the zone of inhibition values was recorded highest zone of inhibition (19 ± 1.2 mm) against the strains S. epidermis followed by B. cereus and Clostridium spp. Further adult zebrafish were found to be less toxic to ZnS-SnS BM NPs after 96 h of exposure, with an LD50 of 100 µg/L. The toxicity escalated as concentrations increased. Behavior test showed normal swimming, learning, and memory in open tank and T-maze tests, while 100 µg/L showed pausing/frozen time in zebra fish therefore low doses are considered safe. Hence by employing ZnS-SnS BM NPs can be engaged in waste water treatment for PAH degradation.


Assuntos
Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Animais , Peixe-Zebra , Adsorção , Fenantrenos/toxicidade , Fenantrenos/química , Hidrocarbonetos Policíclicos Aromáticos/toxicidade
6.
Chemosphere ; 343: 140075, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37678601

RESUMO

In this study, a trimetallic nanocomposite comprising Silver Copper-Nickel (Ag-Cu-Ni TNC) was synthesized and analysed for its efficiency in degrading benzene and benzopyrene, which has five fused benzene rings. Fabrication of trimetallic nanocomposites were characterized using UV spectroscopy, FTIR studies, SEM EDAX, and DLS results. XRD confirmed the cubic crystalline Fcc structure of Ag-Cu-Ni TNC. Photocatalytic degradation analysis revealed that Ag-Cu-Ni TNC has the efficient photocatalytic ability, and the optimum condition required for efficient degradation of benzene and benzopyrene was identified as 2 µg/mL of PAH molecule, 10 µg/mL of Ag-Cu-Ni TNC at pH 5, stirring time of 2 h placed under UV light. Based on these optimum conditions, kinetic and isotherm studies were performed, revealing that the adsorption of benzene and benzopyrene by Ag-Cu-Ni TNC fits well with the Pseudo-second order kinetic model and Freundlich isotherm model. Thus, our study's adsorption of PAH molecule from aqueous solution takes place through chemisorption and involves heterogeneous adsorption phenomena.

7.
Environ Res ; 235: 116672, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37453502

RESUMO

The heavy metals (HMs) in seafood are alarming due to their biomagnification in the food chain. The concentrations of As, Cd, Hg, Pb, Cr, and Ni in both fresh and dried fish were quantified, and the potential exposure and safe intake levels for human consumption were assessed by the European Commission (EC) and the Food Safety Standard Authority of India (FSSAI). HMs concentrations ranged from 0.003 mg/kg (Cr) to 2.08 mg/kg for (As) and 0.007 mg/kg (Hg) to 2.76 mg/kg (As). Cd, Hg, and Pb levels in fresh and dried fish were below the maximum residue limits (MRLs) set by the EC and FSSAI, which were 0.1 mg/kg, 0.5 mg/kg, and 0.3 mg/kg, respectively. Cr and As concentrations were also below the MRLs of 12 mg/kg and 76 mg/kg for aquatic products specified by FSSAI. The concentration of HMs in fresh and dried fish was found in the order of As > Cr > Ni > Pb > Cd > Hg and As > Cd > Cr > Ni > Pb > Hg, while the fresh and dried fishes contained HMs in the following order: E. areolatus > S. longiceps > L.lentjen > S. barracuda > E. affinis > S. javus and DA > DS > DR > DB > DSF. The metal pollution index (MPI) validates seafood is HMs free, while the single (Pi) and Nemerow integrated pollution index (Pnw) indicate that concentrations of Cd and As in fresh and dried fish have exceeded the threshold value. The target hazard quotient (THQ<1), hazard index (HI < 1), and target cancer risk (TCR<10-4) indicate that there are no non-carcinogenic and carcinogenic risks through the consumption of seafood and seafood products collected from the Tuticorin coast and marketed at the domestic and international levels. The preliminary findings emphasize the importance of formulating domestic legislation/government initiatives to promote seafood and its consumption. The attainment of this objective shall be facilitated by examining the levels of persistent organic pollutants (POPs) in seafood and evaluating its potential risk to consumers.


Assuntos
Mercúrio , Metais Pesados , Poluentes Químicos da Água , Animais , Humanos , Cádmio/análise , Chumbo , Alimentos Marinhos/análise , Contaminação de Alimentos/análise , Medição de Risco , Metais Pesados/análise , Mercúrio/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise
8.
Environ Res ; 231(Pt 1): 116033, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37142082

RESUMO

The current study aimed to investigate the effects of lead nitrate exposure on the enzymatical, haematological, and histological changes in the gill, liver, and kidney of Pangasius hypophthalmus. The fish were divided into six groups and treated with different Pb concentrations. The LC50 value of Pb was 55.57 mg/L at 96 h for P. hypophthalmus, and sublethal toxicity was assessed for 45 days at 1/5th (11.47 mg/L) and 1/10th (5.57 mg/L) of LC50 concentration. Enzymes such as aspartate aminotransferase (AST), alanine aminotransferase (ALT) levels, alkaline phosphate (ALP), and lactate dehydrogenase (LDH) content increased significantly during sublethal toxicity of Pb. The reduction of HCT and PCV indicates an anemic condition due to the toxicity of Pb. Differential leucocytes, lymphocytes, and monocytes and their % values significantly decreased, indicating Pb exposure. The main histological changes observed in the gills were the destruction of secondary lamellae, the fusion of adjacent gill lamellae, primary lamellae hypertrophy, and severe hyperplasia, while in kidney exposed to Pb showed melanomacrophages, increased periglomerular, peritubular space, vacuolation, shrunken glomerulus, destruction of tubular epithelium, and hypertrophy of distal convoluted segment. The liver showed severe necrosis and rupture of hepatic cells, hyper trepheoid bile duct, shifting of nuclei, and vascular hemorrhage, while in the brain, binucleus, mesoglea cells, vacuole, and ruptured nucleus were observed. In conclusion, P. hypophthalmus, which has been exposed to Pb has developed a number of toxicity markers. Consequently, prolonged exposure to higher Pb concentrations may be harmful to fish health. The findings strongly suggest that the lead had a detrimental impact on the P. hypophthalmus population, as well as on the water quality and non-target aquatic organisms.


Assuntos
Peixes-Gato , Metais Pesados , Poluentes Químicos da Água , Animais , Chumbo/toxicidade , Metais Pesados/toxicidade , Antioxidantes/farmacologia , Fígado , Brânquias , Poluentes Químicos da Água/toxicidade
9.
Environ Res ; 231(Pt 2): 116130, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37201702

RESUMO

Studies have investigating the detoxification and antioxidant enzymes with melatonin under pesticide stress in many vertebrates, whereas no reports produced in invertebrates. In this study possible role of melatonin and luzindole effect on fipronil toxicity and the detoxification, antioxidant enzymes in H. armigera has been reported. Result showed high toxicity of fipronil treatment (LC50 4.24 ppm), followed by increased LC50 value with melatonin pretreatment (6.44 ppm). Whereas decreased toxicity was observed with melatonin and luzindole combination (3.72 ppm). The detoxification enzymes AChE, esterase and P450 were increased in larval head and whole body with exogenous melatonin level compared to control 1-1.5 µmol/mg of protein. The antioxidant levels of CAT, SOD and GST in whole body and head tissue had been increased by melatonin and fipronil combination 1.1-1.4 unit/mg of protein followed by GPx and GR in larval head (1-1.2 µmol/mg of protein). Mean while the luzindole antagonist inhibits CAT, SOD, GST and GR oxidative enzyme level (1-1.5 fold) in most of the tissue compared to melatonin and fipronil treatment (p < 0.01). Hence this study concludes that the melatonin pretreatment can reduce the fipronil toxicity by enhanced detoxification and antioxidant enzyme system in H. armigera.


Assuntos
Melatonina , Mariposas , Animais , Antioxidantes/farmacologia , Melatonina/farmacologia , Larva/metabolismo , Mariposas/metabolismo , Superóxido Dismutase/metabolismo
10.
Environ Res ; 225: 115602, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36863656

RESUMO

The impact of ZnO/SnO2/reduced graphene oxide nanocomposites (ZnO/SnO2/rGO NCs) for improved photocatalytic degradation of organic dye pollution is examined in this study. The developed ternary nanocomposites had a variety of characteristics that were detected, such as crystallinity, recombination of photogenerated charge carriers, energy gap, and surface morphologies. When rGO was added to the mixture, the optical band gap energy of ZnO/SnO2 was lowered, which improved the photocatalytic activity. Additionally, in comparison to ZnO, ZnO/rGO, SnO2/rGO samples, the ZnO/SnO2/rGO nanocomposites demonstrated exceptional photocatalytic effectiveness for the destruction of orange II (99.8%) and reactive red 120 dye (97.02%), respectively after 120 min exposure to sunlight. The high electron transport properties of the rGO layers, which make it feasible to efficiently separate electron-hole pairs, are attributed to the enhanced photocatalytic activity of the ZnO/SnO2/rGO nanocomposites. According to the results, synthesized ZnO/SnO2/rGO nanocomposites are a cost-efficient option for removing dye pollutants from an aqueous ecosystem. Studies show that ZnO/SnO2/rGO nanocomposites are effective photocatalysts and may one day serve as the ideal material to reduce water pollution.


Assuntos
Poluentes Ambientais , Nanocompostos , Óxido de Zinco , Ecossistema
11.
Environ Res ; 233: 115601, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36863657

RESUMO

The advancement of effective and long-lasting electrocatalysts for energy storage devices is crucial to reduce the impact of the energy crisis. In this study, a two-stage reduction process was used to synthesize carbon-supported cobalt alloy nanocatalysts with varying atomic ratios of cobalt, nickel and iron. The formed alloy nanocatalysts were investigated using energy-dispersive X-ray spectroscopy, X-ray diffraction, and transmission electron microscopy to determine their physicochemical characterization. According to XRD results, Cobalt-based alloy nanocatalysts form a face-centered cubic solid solution pattern, illustrating thoroughly mixed ternary metal solid solutions. Transmission electron micrographs also demonstrated that samples of carbon-based cobalt alloys displayed homogeneous dispersion at particle sizes ranging from 18 to 37 nm. Measurements of cyclic voltammetry, linear sweep voltammetry, and chronoamperometry revealed that iron alloy samples exhibited much greater electrochemical activity than non-iron alloy samples. The alloy nanocatalysts were evaluated as anodes for the electrooxidation of ethylene glycol in a single membraneless fuel cell to assess their robustness and efficiency at ambient temperature. Remarkably, in line with the results of cyclic voltammetry and chronoamperometry, the single-cell test showed that the ternary anode works better than its counterparts. The significantly higher electrochemical activity was observed for alloy nanocatalysts containing iron than for non-iron alloy catalysts. Iron stimulates nickel sites to oxidize cobalt to cobalt oxyhydroxides at lower over-potentials, which contributes to the improved performance of ternary alloy catalysts containing iron.


Assuntos
Etilenoglicol , Níquel , Cobalto , Ligas/química , Carbono/química
12.
Fish Physiol Biochem ; 49(5): 787-799, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36717424

RESUMO

Globally, the prevalence and pollution of pharmaceutical drugs in aquatic environments have been steadily increasing. This study sought to evaluate the effects of 14 days of exposure to environmental-relevant doses (ibuprofen 0.5, 5, and 50 µg/L, and carbamazepine 0.005, 1, and 10 µg/L) of the nonsteroidal anti-inflammatory drugs ibuprofen and carbamazepine in the freshwater fish Oreochromis mossambicus. The results showed a significant (P < 0.05) decrease in O. mossambicus superoxide dismutase, catalase, biotransformation enzymes, glutathione-s-transferase, glutathione peroxidase, oxidative stress lipid peroxidation, protein carbonyl activity, cellular damage metallothionine, reduced glutathione, immunological activities, and respiratory burst activity. Consequently, the acquired data revealed that O. mossambicus treated with ibuprofen and carbamazepine shows more significant alterations in metabolic depression, biochemical parameters, and oxidative stress. In addition, increased neurotoxic effects were observed in ibuprofen and carbamazepine treated O. mossambicus.


Assuntos
Tilápia , Animais , Tilápia/metabolismo , Antioxidantes/metabolismo , Ibuprofeno/toxicidade , Ibuprofeno/metabolismo , Estresse Oxidativo , Catalase/metabolismo , Superóxido Dismutase/metabolismo , Peroxidação de Lipídeos , Carbamazepina/toxicidade , Carbamazepina/metabolismo
13.
Toxics ; 10(11)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36422901

RESUMO

Massive quantities of unadvisable synthetic pesticides are used in modern agricultural industries in order to increase productivity to convene food demands. Wild birds are an excellent bio-indicator of environmental contaminations as pesticides and heavy metals are intentionally highly hazardous pollutants. Considerably, raptorial birds (owls) attract consumers in the food chain and food web because they have wider forager and foraging grounds. In the current investigation, owl pellets were used as a viable tool and novel approach to detecting environmental contaminants. In total, 30 pellets comprising five species were collected from selected farmlands, and 11 metals (Cr, Mn, Co, Mo, Se, V, Cu, Ni, Pb, Zn, and Fe) were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). Undeniably, the Brown Fish Owl showed more metal accumulation than the Barn Owl, Spotted Owl, Indian Eagle Owl, and Mottled Wood Owl. Among the species, the levels of metals such as Manganese (Mn), Molybdenum (Mo), Vanadium (V), Copper (Cu) and Zinc (Zn) varied significantly (p < 0.05). Nonetheless, the research revealed that the agroecosystem was contaminated with heavy metals. The present outcome highlights that the management of the environment, especially the agroecosystem, must be examined with a careful assessment of contaminants, and it is a vital resource for human and other related wildlife faunal communities.

14.
Life (Basel) ; 12(9)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36143338

RESUMO

Host genetic variability plays a pivotal role in modulating COVID-19 clinical outcomes. Despite the functional relevance of protein-coding regions, rare variants located here are less likely to completely explain the considerable numbers of acutely affected COVID-19 patients worldwide. Using an exome-wide association approach, with individuals of European descent, we sought to identify common coding variants linked with variation in COVID-19 severity. Herein, cohort 1 compared non-hospitalized (controls) and hospitalized (cases) individuals, and in cohort 2, hospitalized subjects requiring respiratory support (cases) were compared to those not requiring it (controls). 229 and 111 variants differed significantly between cases and controls in cohorts 1 and 2, respectively. This included FBXO34, CNTN2, and TMCC2 previously linked with COVID-19 severity using association studies. Overall, we report SNPs in 26 known and 12 novel candidate genes with strong molecular evidence implicating them in the pathophysiology of life-threatening COVID-19 and post-recovery sequelae. Of these few notable known genes include, HLA-DQB1, AHSG, ALOX5AP, MUC5AC, SMPD1, SPG7, SPEG,GAS6, and SERPINA12. These results enhance our understanding of the pathomechanisms underlying the COVID-19 clinical spectrum and may be exploited to prioritize biomarkers for predicting disease severity, as well as to improve treatment strategies in individuals of European ancestry.

15.
Conserv Biol ; 36(4): e13918, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35554972

RESUMO

The pink pigeon (Nesoenas mayeri) is an endemic species of Mauritius that has made a remarkable recovery after a severe population bottleneck in the 1970s to early 1990s. Prior to this bottleneck, an ex situ population was established from which captive-bred individuals were released into free-living subpopulations to increase population size and genetic variation. This conservation rescue led to rapid population recovery to 400-480 individuals, and the species was twice downlisted on the International Union for the Conservation of Nature (IUCN) Red List. We analyzed the impacts of the bottleneck and genetic rescue on neutral genetic variation during and after population recovery (1993-2008) with restriction site-associated sequencing, microsatellite analyses, and quantitative genetic analysis of studbook data of 1112 birds from zoos in Europe and the United States. We used computer simulations to study the predicted changes in genetic variation and population viability from the past into the future. Genetic variation declined rapidly, despite the population rebound, and the effective population size was approximately an order of magnitude smaller than census size. The species carried a high genetic load of circa 15 lethal equivalents for longevity. Our computer simulations predicted continued inbreeding will likely result in increased expression of deleterious mutations (i.e., a high realized load) and severe inbreeding depression. Without continued conservation actions, it is likely that the pink pigeon will go extinct in the wild within 100 years. Conservation rescue of the pink pigeon has been instrumental in the recovery of the free-living population. However, further genetic rescue with captive-bred birds from zoos is required to recover lost variation, reduce expression of harmful deleterious variation, and prevent extinction. The use of genomics and modeling data can inform IUCN assessments of the viability and extinction risk of species, and it helps in assessments of the conservation dependency of populations.


La paloma rosada (Nesoenas mayeri) es una especie endémica de Mauricio que se ha recuperado impresionantemente después de un grave cuello de botella poblacional a principios de la década de 1970 que duró hasta inicios de la década de 1990. Antes de este cuello de botella se había establecido una población ex situ de la cual se liberaban individuos reproducidos en cautiverio a las subpoblaciones en libertad para incrementar la variación genética y el tamaño poblacional. Este rescate de conservación derivó en una recuperación rápida de la población (400-480 individuos) y la especie cambió positivamente de categoría dos veces en la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza (UICN). Analizamos los impactos del cuello de botella y el rescate genético sobre la variación genética neutral durante y después de la recuperación poblacional (de 1993 a 2008) mediante secuenciación RAD, análisis de microsatélites y análisis genéticos cuantitativos de los datos del libro genealógico de 1112 aves ubicadas en zoológicos de Europa y los Estados Unidos. Usamos simulaciones por computadora para estudiar los cambios pronosticados en la variación genética y en la viabilidad poblacional del pasado hacia el futuro. La variación genética declinó rápidamente, a pesar de la recuperación poblacional, y el tamaño efectivo de la población fue aproximadamente un orden de magnitud más pequeño que el tamaño del censo. La especie contó con una carga genética elevada de casi 15 equivalentes letales para la longevidad. Nuestras simulaciones pronostican que la endogamia continua probablemente resultará en un incremento en la expresión de mutaciones deletéreas (es decir, una carga realizada elevada) y en una depresión endogámica severa. Sin acciones continuas para la conservación, es probable que la paloma rosada esté extinta en vida libre dentro de cien años. El rescate de conservación de la paloma rosada ha sido fundamental en la recuperación de la población silvestre; sin embargo, se requiere de un rescate genético adicional con las aves de reproducción en cautiverio de los zoológicos para recuperar la variación perdida, reducir la expresión de la variación deletérea dañina y prevenir la extinción. El uso de la genómica y los datos modelados puede orientar las valoraciones de la UICN sobre la viabilidad y el riesgo de extinción de las especies, además de que ayuda en la evaluación de la dependencia que tienen las poblaciones de la conservación.


Assuntos
Aves , Conservação dos Recursos Naturais , Animais , Aves/genética , Espécies em Perigo de Extinção , Europa (Continente) , Variação Genética , Genômica , Densidade Demográfica
16.
J Family Community Med ; 28(2): 77-84, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194271

RESUMO

BACKGROUND: General practitioners (GPs) and family medicine physicians (FMPs) have a vital role to play in co-ordinating the care for mental disorders. The objective of this study was to determine the perception of GPs and FMPs on the use of cognitive-behavioral therapy (CBT) for depression in Saudi Arabia, and the barriers against the implementation of CBT in such settings. MATERIALS AND METHODS: All physicians working in Primary Healthcare Centers and Family Medicine Clinics in Saudi Arabia were targeted and invited to participate in this cross-sectional study. A self-administered online questionnaire was sent via E-mail through the Saudi Commission for Health Specialties and the Saudi Society of Family and Community Medicine. Data was collected using an existing validated questionnaire and was modified to fit the objectives of current study. RESULTS: A total of 469 FMPs and GPs completed the survey; the mean age of respondents was 38 years. More than half of the FMPs' and GPs' (53%) showed a positive perception of the use of CBT in primary healthcare settings. Most participants (91.9%) were willing to use CBT if they had adequate education and training. More than half of the participants (59.5%) thought it was time-consuming, while 39% thought that CBT training was a very time-intensive process. CONCLUSION: We conclude that more than half of the physicians clearly had a good perception of the effectiveness of CBT administration in primary healthcare settings. Younger physicians were more perceptive. The most agreed-on barrier to CBT implementation was the lack of training and education.

17.
Chemosphere ; 278: 130372, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33839399

RESUMO

In recent times, agricultural practices mainly rely on agrochemicals and pesticides to safe-guard edible crops against various pests and to ensure high yields. However, their indiscriminate use may cause severe environmental hazards that directly and negatively affect soil microorganisms and crop productivity. Considering these, present study was aimed to assess the toxicity of carbamate pesticides namely carbamoyl (CBL), methomyl (MML) and carbofuran (CBN) using bacterial and plant (Vigna mungo L.) bioassays. All pesticide doses (25-100 µg mL-1) showed negative effect on bacteria as well as plant. Growth, morphology, survival, cellular respiration and inner membrane permeability of Sinorhizobiumsaheli was hampered when exposed to pesticides. Pesticide induced morphological changes viz. aberrant margins; cellular cracking and distortion/damage in S. saheli were obvious under scanning electron microscope (SEM). The 100 µgCBNmL-1 had maximum inhibitory effect and it reduced survivability of S. saheli by 75%. In addition, biofilm formation ability of S. saheli was inhibited in a pesticides-dose dependent manner and it was statistically (p ≤ 0.05) significant. Pesticides indorsed significant changes in biomarker enzymatic assays and oxidative stress parameters towards S. saheli. Furthermore, at 100 µgCBNmL-1, germination efficiency, root, shoot length, plant survival and tolerance index of V. mungo were decrease by 50, 75, 65, 70 and 66%, respectively over control. Staining of pesticide treated roots with fluorescently labeled dyes propidium iodide (PI) and acridine orange (AO) showed increased oxidative stress, ROS generation and membrane permeability as revealed under confocal laser scanning microscope (CLSM). Furthermore, stressor metabolites and antioxidant enzymes in plant seedlings were progressively enhanced with increasing concentration of pesticides. Conclusively, present finding bestow an insights into a mechanistic approach of carbamate pesticide induced phyto, morpho and cellular toxic effects towards soil bacterium as well as plant with forthcoming implications for designing the pesticides to reduce their toxic/harmful effects.


Assuntos
Praguicidas , Bactérias , Bioensaio , Carbamatos/toxicidade , Praguicidas/toxicidade , Plantas
18.
Chemosphere ; 268: 129348, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33360001

RESUMO

A novel adsorbent was developed based on nitrile functionalized calix [4]arene grafted onto magnetic graphene oxide (N-Calix-MGO) for remediation of arsenic (III) ions from aqueous media. The nanocomposite was characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The effective parameters on adsorption efficiency such as pH, adsorbent dosage, contact time, initial concentration, and temperature were studied. The adsorption process was provided with a high removal efficiency up to (90%) at pH 6 which followed by IUPAC Type II pattern. The mathematical models of kinetics and isotherm validated the experimental process. The adsorption kinetic is followed pseudo-first-order model with R2 > 0.9. The adsorption equilibrium was well fitted on the Freundlich model (R2 ∼ 0.96) as compared Langmuir model (R2 ∼ 0.75). Hence, the Freundlich model suggested a multilayer sorption pattern with a physisorption mechanism for arsenic (III) uptake ono developed nanocomposite with a sorption capacity of 67 mg/g for arsenic. The Gibbs free energy (ΔG° < -20 kJ/mol) showed As(III) uptake ono N-Calix-MGO nanocomposite was the physical adsorption mechanism.


Assuntos
Arsênio , Calixarenos , Poluentes Químicos da Água , Adsorção , Grafite , Concentração de Íons de Hidrogênio , Cinética , Fenômenos Magnéticos , Nitrilas , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
19.
Avian Dis ; 64(2): 130-134, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32550612

RESUMO

Trichomonas gallinae, a single-celled protozoan parasite, is a causative agent of the disease trichomonosis, which is distributed worldwide and has recently been highlighted as a pandemic threat to several wild bird species. The aim of this study was to determine the prevalence and genotypic diversity of T. gallinae in Riyadh, Saudi Arabia. For this purpose, 273 oral swab samples from different bird species (feral pigeon Columba livia, common mynah Acridotheres tristis, chicken Gallus gallus domesticus, turkey Meleagris gallopavo, and ducks Anatidae) were collected and tested for T. gallinae infection with InPouch™ TV culture kits. The results showed that the overall prevalence of T. gallinae in these samples was 26.4% (n = 72). The PCRs were used to detect the internal transcribed spacer (ITS) region of T. gallinae, and the results of the sequence analysis indicated genetic variation. Among 48 sequences, we found 15 different ribotypes, of which 12 were novel. Three had been previously described as ribotypes A, C, and II. To our knowledge, this study demonstrated the presence of T. gallinae strain diversity in Saudi Arabian birds for the first time and revealed that ribotypes A and C are predominant among Riyadh birds.


Aislamiento y caracterización de nuevos ribotipos de Trichomonas gallinae que infectan aves domésticas y silvestres en Riad, Arabia Saudita. Trichomonas gallinae, un parásito protozoario unicelular, es un agente causal de la enfermedad tricomonasis, que se distribuye en todo el mundo y recientemente se ha destacado como una amenaza pandémica para varias especies de aves silvestres. El objetivo de este estudio fue determinar la prevalencia y la diversidad genotípica de T. gallinae en Riad, Arabia Saudita. Para este propósito, se recolectaron y analizaron 273 muestras de hisopos orales de diferentes especies de aves (paloma silvestre Columba livia, miná común Acridotheres tristis, pollos Gallus gallus domesticus, pavos Meleagris gallopavo y patos Anatidae) para detectar la infección por T. gallinae mediante cultivo con el estuche InPouch ™ TV. Los resultados mostraron que la prevalencia general de T. gallinae en estas muestras fue del 26.4% (n = 72). Se utilizó la técnica de PCR para detectar la región espaciadora transcrita interna (ITS) de T. gallinae, y los resultados del análisis de secuencias indicaron variación genética. Entre 48 secuencias, se encontraron 15 ribotipos diferentes, de los cuales 12 eran nuevos. Tres habían sido descritos previamente como ribotipos A, C y II. Hasta donde se conoce, este estudio demostró la presencia de diversidad entre cepas de T. gallinae en aves de Arabia Saudita por primera vez y reveló que los ribotipos A y C son los predominantes entre las aves de Riad.


Assuntos
Doenças das Aves/epidemiologia , Aves , Genótipo , Tricomoníase/veterinária , Trichomonas/genética , Animais , Doenças das Aves/parasitologia , Galinhas , Columbidae , Patos , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/parasitologia , Prevalência , Arábia Saudita/epidemiologia , Estorninhos , Tricomoníase/epidemiologia , Tricomoníase/parasitologia , Perus
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