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1.
Arch Biochem Biophys ; 752: 109889, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38215959

RESUMO

Hemolysis in red blood cells followed by hemoglobin degradation results in high hemin levels in the systemic circulation. Such a level of hemin is disastrous for cells and tissues and is considerably responsible for the pathologies of diseases like severe malaria. Hemin's hydrophobic chemical nature and structure allow it to bind several proteins leading to their functional modification. Such modifications in physiologically relevant proteins can have a high impact on various cellular processes. HSPA8 is a chaperone that has a protective role in oxidative stress by aiding protein refolding. Through ATPase activity assays we found that hemin can competitively inhibit ATP hydrolysis by the chaperone HSPA8. Hemin as such does not affect the structural integrity of the protein which is inferred from CD spectroscopy and Gel filtration but it hinders the ATP-dependent foldase function of the chaperone. HSPA8 was not able to cause the refolding of the model protein lysozyme in the presence of hemin. The loss in HSPA8 function was due to competition between hemin and ATP as the chaperone was able to regain the foldase function when the concentration of ATP was gradually increased with hemin present at the inhibitory concentration. In-silico studies to establish the competition for the specific binding site revealed that ATP was unable to replace hemin from the ATP binding pocket of HSPA8 and was forced to form a non-specific and unstable complex. In-vitro isothermal calorimetry revealed that the affinity of ATP for binding to HSPA8 was reduced 22 folds in the presence of hemin. The prevention of HSPA8's cytoprotective function by hemin can be a major factor contributing to the overall cellular damage during hemin accumulation in the case of severe malaria and other hemolytic diseases.


Assuntos
Hemina , Malária , Humanos , Hemina/farmacologia , Chaperonas Moleculares , Hemólise , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Choque Térmico HSC70
2.
Opt Express ; 31(5): 8465-8478, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859961

RESUMO

In this article we present modelling results of the amplification of High Order Harmonics (HOH) carrying orbital angular momentum (OAM) in plasma amplifiers created from krypton gas and silver solid targets. The resulting amplified beam is characterized in terms of intensity, phase and decomposition in helical and Laguerre-Gauss modes. Results show that the amplification process conserves OAM, although some degradation is apparent. Several structures appear in the intensity and phase profiles. These structures have been characterized with our model and related to refraction and interference with the plasma self-emission. Thus, these results not only demonstrate the capability of plasma amplifiers to deliver HOH amplified beams carrying OAM but also pave the way towards using HOH carrying OAM as a probe beam to diagnose the dynamics of hot, dense plasmas.

3.
Med J Armed Forces India ; 79(1): 64-71, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36605340

RESUMO

Background: We have been in constant search of novel innovations to decrease the high morbidity after Pancreaticoduodenectomy (PD). Pancreaticojejunostomy (PJ) and pancreaticogastrostomy (PG) are the two different methods of reconstruction after PD. However, the existing data is ambiguous in supporting either of them as the preferred technique of reconstruction. Methods: This was a single-center prospective observational study that included 64 patients who underwent PD over two years. We compared PG with PJ as a method of reconstruction after PD. The primary objective was to assess whether PG decreases the rate of postoperative pancreatic fistula (POPF) rates or not. Secondary objectives comprised analysis of perioperative outcomes, 30-day and 90-day mortality. Results: Pancreatic fistula was significantly lower in PG as compared to the PJ group (24% vs. 47%) with a p-value of 0.027. The incidence of clinically pertinent (grade B) fistula was only 3% in the PG group and 32% in the PJ group. PG group had a higher incidence of post pancreatectomy hemorrhage (PPH) and delayed gastric emptying (DGE). No statistically significant difference was seen between either group need for blood transfusion, re-exploration, re-admissions, ICU stay, or length of hospital stay, and 30-day and 90-day mortality. Pancreatic texture and high BMI were independent predictors for pancreatic fistula. Conclusion: PG when compared to PJ for reconstruction after PD, decreases the rate of POPF significantly; however, it is associated with an elevated risk of DGE and PPH. There was no difference in 30-day and 90-day mortality between both the treatment groups.

4.
Mutagenesis ; 37(1): 44-59, 2022 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-35230445

RESUMO

Incessant production, pervasive applications in different fields, and eventually unintended exposure of cobalt oxide nanoparticles (Co3O4 NPs) lead to rise in their toxicity studies toward human health. However, the information regarding the potential toxicity mechanisms of Co3O4 NPs especially genotoxicity is still sparse with missing interconnections. So far, only solitary reports on Co3O4 NPs are at hand, bearing witness to reactive oxygen species (ROS)-mediated DNA damage in lung cells. To address this, we evaluated the Co3O4 NP-induced cytotoxic and genotoxic potential in Chinese hamster lung fibroblast cell line (V79). Our preliminary results demonstrate that Co3O4 NPs at concentrations of 20-100 µg/ml induced moderate mortality after 24-h exposure. However, these low concentrations caused a significant reduction in various organelles' activity in a concentration-dependent manner. Mitochondrial activity and membrane potential were found to be compromised due to NP exposure in a concentration-dependent manner. The study affirms that Co3O4 NPs inhibited lysosomal activity in V79 cells. In addition to this, Co3O4 NPs are also found to stimulate free oxygen radical generation. Genotoxicity studies revealed a potent and dose-dependent effect of non-cytotoxic concentrations of Co3O4 NPs in the induction of DNA lesions. Interestingly, N-acetylcysteine, a free oxygen radical scavenger (5, 10 mM, pretreatment) inhibited the progression of free oxygen radicals and induction of Co3O4 NP-mediated DNA lesions. This suggests the ROS-mediated genotoxic potential of Co3O4 NPs.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Animais , Sobrevivência Celular , Cobalto , Cricetinae , Cricetulus , Dano ao DNA , Fibroblastos/metabolismo , Humanos , Pulmão/metabolismo , Nanopartículas Metálicas/toxicidade , Nanopartículas/toxicidade , Estresse Oxidativo , Óxidos , Espécies Reativas de Oxigênio/metabolismo
5.
Ecotoxicol Environ Saf ; 247: 114205, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306616

RESUMO

For many years, the impact of Particulate Matter (PM) in the ambient air has been one of the major concerns for the environment and human health. The consideration of the heterogeneity and complexity of different size fractions is notably important for the assessment of PM toxicological effects. The aim of the study was to present a comprehensive size-composition-morphology characterization and to assess the oxidative potential, genotoxicity, and mutagenicity of the atmospheric PM fractions, collected by using MOUDI near a busy roadside in Lucknow, India. Physicochemical characterization of ambient coarse particles (1.8-10 µm), fine particles (0.32-1.8 µm), quasi-ultrafine (0.1-0.32 µm) and ultrafine particles (≤0.1 µm) along with SRM 1649b was done using TEM, SEM, DLS, NTA, ICP-MS, and IC in parallel with the estimation of exogenous Reactive Oxygen Species (ROS) by acellular assays. In this study, two different acellular assays, dithiothreitol (DTT) and the CM-H2DCFDA assay, indicated stronger mass-normalized bioactivity for different size ranges. Enrichment factor analysis indicated that the different size fractions were highly enriched with elements of anthropogenic origin as compared to elements of crustal origin. The endotoxin concentration in different size fractions was also estimated. Cellular studies demonstrated significant uptake, cytotoxicity, ultrastructural changes, cellular ROS generation, and changes in the different phases of the cell cycle (Sub G1, G1, S, G2/M) exposed to different size fractions. The Comet assay and the Micronucleus assay were used to estimate genotoxicity. Mutagenic potential was revealed by the HGPRT gene forward mutation assay in V-97 cells. Conclusively, our results clearly indicate that the genotoxic and mutagenic potential of the coarse PM was greater than the other fractions, and interestingly, the ultrafine PM has higher bioactivity as compared to quasi-ultrafine PM.


Assuntos
Poluentes Atmosféricos , Material Particulado , Humanos , Material Particulado/análise , Mutagênicos/toxicidade , Mutagênicos/análise , Poluentes Atmosféricos/análise , Espécies Reativas de Oxigênio/análise , Tamanho da Partícula , Dano ao DNA , Estresse Oxidativo
6.
Sensors (Basel) ; 22(1)2021 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-35009674

RESUMO

Light beams carrying Orbital Angular Momentum (OAM), also known as optical vortices (OV), have led to fascinating new developments in fields ranging from quantum communication to novel light-matter interaction aspects. Even though several techniques have emerged to synthesize these structured-beams, their detection, in particular, single-shot amplitude, wavefront, and modal content characterization, remains a challenging task. Here, we report the single-shot amplitude, wavefront, and modal content characterization of ultrashort OV using a Shack-Hartmann wavefront sensor. These vortex beams are obtained using spiral phase plates (SPPs) that are frequently used for high-intensity applications. The reconstructed wavefronts display a helical structure compatible with the topological charge induced by the SPPs. We affirm the accuracy of the optical field reconstruction by the wavefront sensor through an excellent agreement between the numerically backpropagated and experimentally obtained intensity distribution at the waist. Consequently, through Laguerre-Gauss (LG) decomposition of the reconstructed fields, we reveal the radial and azimuthal mode composition of vortex beams under different conditions. The potential of our method is further illustrated by characterizing asymmetric Gaussian vortices carrying fractional average OAM, and a realtime topological charge measurement at a 10Hz repetition rate. These results can promote Shack-Hartmann wavefront sensing as a single-shot OV characterization tool.

7.
Opt Express ; 28(20): 28924-28941, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33114801

RESUMO

We investigate the coherence of plasma-based soft X-ray laser (XRL) for different conditions that can alter the electron density in the gain region. We first measure the source temporal coherence in amplified spontaneous emission (ASE) mode. We develop a data analysis procedure to extract both its spectral width and pulse duration. These findings are in agreement with the spectral line shape simulations and seeded operation experimental results. Utilizing the deduced spectral width and pulse duration in a one-dimensional Bloch-Maxwell code, we reproduce the experimental temporal coherence properties of the seeded-XRL. Finally, we demonstrate efficient lasing in ASE and seeded mode at an electron density two times higher than the routine conditions. In this regime, using Bloch-Maxwell modeling, we predict the pulse duration of the seeded XRL to be ∼500fs.

8.
J Appl Toxicol ; 39(5): 735-750, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30618096

RESUMO

In recent years, the large-scale production of ZnO nanoparticles (NPs) for various applications is increasing exponentially and may pose serious health issues when inhaled either during occupational exposure or in consumer settings. The mechanisms underlying the toxicity of NPs have recently been studied intensively. Despite the existing studies, the mutagenicity of ZnO NPs in the eukaryotic system is still unclear. Therefore, the aim of the present study was to investigate the mutagenic potential of ZnO NPs using Chinese hamster lung fibroblast cells (V-79) as an in-vitro model. The study has demonstrated a significant uptake of ZnO NPs by flow cytometry with the confirmation of transmission electron microscopy. A reduction in cell viability was observed with a concomitant increase in reactive oxygen species (**P < 0.01, ***P < 0.001) after ZnO NP (1-20 µg/mL) exposure. Excessive reactive oxygen species can induce oxidative stress, which leads to genotoxic insult, and further gene mutation. Apart from measuring the genotoxicity by Comet assay, a change of 2.84-fold in the HGPRT gene mutant frequency was observed by the mammalian gene forward mutation assay. All the genotoxicity endpoints such as chromosomal break, DNA damage and mutagenicity were observed at 6 hours of ZnO NP exposure. Our results also showed that ZnO NPs manifested the cell cycle arrest, ultrastructural modifications and further cell death. A significant (**P < 0.01, ***P < 0.001) increase in the apoptotic cells was detected using annexin V-fluorescein isothiocyanate/propidium iodide double staining by flow cytometry. Our findings presented here clearly stimulate the need for careful regulations of ZnO NPs.


Assuntos
Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Dano ao DNA , Fibroblastos/efeitos dos fármacos , Hipoxantina Fosforribosiltransferase/genética , Nanopartículas/toxicidade , Óxido de Zinco/toxicidade , Animais , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular , Ensaio Cometa , Cricetulus , Fibroblastos/patologia , Testes para Micronúcleos , Mutação , Nanopartículas/química , Tamanho da Partícula , Propriedades de Superfície , Óxido de Zinco/química
9.
Ecotoxicol Environ Saf ; 182: 109375, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299474

RESUMO

The continuous and extensive use of pesticides, particularly in the field of agriculture, leads to contamination of all ecosystems (water, soil, and atmosphere). Among pesticides, fungicides constitute a larger group whose impact on the environment are still poorly studied. Difenoconazole belongs to triazole group of fungicides having high photochemical stability and have low biodegradability, which makes them persistent in water bodies. The present study focuses on the physiological and cytotoxic impact of difenoconazole fungicide on ciliated protozoa, Tetrahymena pyriformis with reference to growth, morphology, behaviour and its generation time. Morphological studies showed changes in the shape and size of T. pyriformis. Our result showed an inhibitory effect on population growth of T. pyriformis and the IC50 concentration was found to be 6.8 µg mL-1.The numbers of generations decreased and generation time was found to be extended in a concentration and time dependent manner. Difenoconazole caused significant depletion in phagocytic activity and also ultra-structural changes were observed by Transmission electron microscopy (TEM) analysis. The results indicate that the Tetrahymena toxicity assay could be used as a complementary system to rapidly elucidate the cytotoxic potential of fungicide.


Assuntos
Dioxolanos/toxicidade , Fungicidas Industriais/toxicidade , Tetrahymena pyriformis , Triazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Tetrahymena pyriformis/efeitos dos fármacos , Tetrahymena pyriformis/fisiologia , Tetrahymena pyriformis/ultraestrutura
10.
Part Fibre Toxicol ; 14(1): 15, 2017 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-28454554

RESUMO

BACKGROUND: Graphite carbon nanofibers (GCNF) have emerged as a potential alternative of carbon nanotubes (CNT) for various biomedical applications due to their superior physico-chemical properties. Therefore in-depth understanding of the GCNF induced toxic effects and underlying mechanisms in biological systems is of great interest. Currently, autophagy activation by nanomaterials is recognized as an emerging toxicity mechanism. However, the association of GCNF induced toxicity with this form of cell death is largely unknown. In this study, we have assessed the possible mechanism; especially the role of autophagy, underlying the GCNF induced toxicity. METHODS: Human lung adenocarcinoma (A549) cells were exposed to a range of GCNF concentrations and various cellular parameters were analyzed (up to 48 h). Transmission electron microscopy, immunofluorescent staining, western blot and quantitative real time PCR were performed to detect apoptosis, autophagy induction, lysosomal destabilization and cytoskeleton disruption in GCNF exposed cells. DCFDA assay was used to evaluate the reactive oxygen species (ROS) production. Experiments with N-acetyl-L-cysteine (NAC), 3-methyladenine (3-MA) and LC3 siRNA was carried out to confirm the involvement of oxidative stress and autophagy in GCNF induced cell death. Comet assay and micronucleus (MN) assay was performed to assess the genotoxicity potential. RESULTS: In the present study, GCNF was found to induce nanotoxicity in human lung cells through autophagosomes accumulation followed by apoptosis via intracellular ROS generation. Mechanistically, impaired lysosomal function and cytoskeleton disruption mediated autophagic flux blockade was found to be the major cause of accumulation rather than autophagy induction which further activates apoptosis. The whole process was in line with the increased ROS level and their pharmacological inhibition leads to mitigation of GCNF induced cell death. Moreover the inhibition of autophagy attenuates apoptosis indicating the role of autophagy as cell death process. GCNF was also found to induce genomic instability. CONCLUSION: Our present study demonstrates that GCNF perturbs various interrelated signaling pathway and unveils the potential nanotoxicity mechanism of GCNF through targeting ROS-autophagy-apoptosis axis. The current study is significant to evaluate the safety and risk assessment of fibrous carbon nanomaterials prior to their potential use and suggests caution on their utilization for biomedical research.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Grafite/toxicidade , Lisossomos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Nanofibras/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Células A549 , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Humanos , Pulmão/efeitos dos fármacos , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície
11.
J Environ Manage ; 181: 728-736, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27558829

RESUMO

Microbial degradation is a useful tool to prevent chemical pollution in soil. In the present study, in-situ bioremediation of polyaromatic hydrocarbons (PAHs) by microbial consortium consisting of Serratia marcescens L-11, Streptomyces rochei PAH-13 and Phanerochaete chrysosporium VV-18 has been reported. In preliminary studies, the consortium degraded nearly 60-70% of PAHs in broth within 7 days under controlled conditions. The same consortium was evaluated for its competence under natural conditions by amending the soil with ammonium sulphate, paddy straw and compost. Highest microbial activity in terms of dehydrogenase, FDA hydrolase and aryl esterase was recorded on the 5(th) day. The degradation rate of PAHs significantly increased up to 56-98% within 7 days under in-situ however almost complete dissipation (83.50-100%) was observed on the 30(th) day. Among all the co-substrates evaluated, faster degradation of PAHs was observed in compost amended soil wherein fluorene, anthracene, phenanthrene and pyrene degraded with half-life of 1.71, 4.70, 2.04 and 6.14 days respectively. Different degradation products formed were also identified by GC-MS. Besides traces of parent PAHs eleven non-polar and five polar products were identified by direct and silylation reaction respectively. Various products formed indicated that consortium was capable to degrade PAHs by oxidation to mineralization.


Assuntos
Biodegradação Ambiental , Hidrocarbonetos Aromáticos/metabolismo , Consórcios Microbianos , Compostos Policíclicos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Solo/química , Meia-Vida , Hidrocarbonetos Aromáticos/química , Phanerochaete/metabolismo , Compostos Policíclicos/química , Poluentes do Solo/análise , Poluentes do Solo/química , Streptomyces/metabolismo
12.
J Appl Toxicol ; 35(10): 1179-88, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26086747

RESUMO

Chromium oxide (Cr2 O3 ) nanoparticles (NPs) are being increasingly used as a catalyst for aromatic compound manufacture, abrading agents and as pigments (e.g., Viridian). Owing to increased applications, it is important to study the biological effects of Cr2 O3 NPs on human health. The lung is one of the main exposure routes to nanomaterials; therefore, the present study was designed to determine the genotoxic and apoptotic effect of Cr2 O3 NPs in human lung epithelial cells (A549). The study also elucidated the molecular mechanism of its toxicity. Cr2 O3 NPs led to DNA damage, which was deduced by comet assay and cytokinesis block micronucleus assay. The damage could be mediated by the increased levels of reactive oxygen species. Further, the oxygen species led to a decrease in mitochondrial membrane potential and an increase in the ratio of BAX/Bcl-2 leading to mitochondria-mediated apoptosis induced by Cr2 O3 NPs, which ultimately leads to cell death. Hence, there is a need of regulations to be imposed in NP usage. The study provided insight into the caspase-dependent mechanistic pathway of apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Compostos de Cromo/toxicidade , Genes p53/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Mutagênicos/toxicidade , Alvéolos Pulmonares/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaio Cometa , Citocinese , Dano ao DNA , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Testes para Micronúcleos , Estresse Oxidativo/efeitos dos fármacos , Alvéolos Pulmonares/citologia , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2/biossíntese
13.
Environ Monit Assess ; 187(6): 391, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26026847

RESUMO

Polyaromatic hydrocarbons (PAHs) utilizing bacteria were isolated from soils of seven sites of Mathura refinery, India. Twenty-six bacterial strains with different morphotypes were isolated. These strains were acclimatized to utilize a mixture of four polycyclic aromatic hydrocarbons, i.e., anthracene, fluorene, phenanthrene, and pyrene, each at 50 mg/L concentration as sole carbon source. Out of total isolates, 15 potent isolates were subjected to 16S rDNA sequencing and identified as a member of diverse genera, i.e., Bacillus, Acinetobacter, Stenotrophomonas, Alcaligenes, Lysinibacillus, Brevibacterium, Serratia, and Streptomyces. Consortium of four promising isolates (Acinetobacter, Brevibacterium, Serratia, and Streptomyces) were also investigated for bioremediation of PAH mixture. This consortium was proved to be efficient PAH degrader resulting in 40-70 % degradation of PAH within 7 days. Results of this study indicated that these genera may play an active role in bioremediation of PAHs.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bacillus/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Monitoramento Ambiental , Indústrias Extrativas e de Processamento , Fluorenos , Índia , Poluição por Petróleo , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos/análise , Pirenos , Solo/química , Poluentes do Solo/análise
14.
Protein J ; 43(1): 48-61, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38066289

RESUMO

Hemin, a byproduct of hemoglobin degradation, inflicts oxidative insult to cells. Following its accumulation, several proteins are recruited for heme detoxification with heme oxygenase playing the key role. Chaperones play a protective role primarily by preventing protein degradation and unfolding. They also are known to have miscellaneous secondary roles during similar situations. To discover a secondary role of chaperones during heme stress we studied the role of the chaperone HSPA8 in the detoxification of hemin. In-silico studies indicated that HSPA8 has a well-defined biophoric environment to bind hemin. Through optical difference spectroscopy, we found that HSPA8 binds hemin through its N-terminal domain with a Kd value of 5.9 ± 0.04 µM and transforms into a hemoprotein. The hemoprotein was tested for exhibiting peroxidase activity using guaiacol as substrate. The complex formed reacts with H2O2 and exhibits classical peroxidase activity with an ability to oxidize aromatic and halide substrates. HSPA8 is dose-dependently catalyzing heme polymerization through its N-terminal domain. The IR results reveal that the polymer formed exhibits structural similarities to ß-hematin suggesting its covalent nature. The polymerization mechanism was tested through optical spectroscopy, spin-trap, and activity inhibition experiments. The results suggest that the polymerization occurs through a peroxidase-H2O2 system involving a one-electron transfer mechanism, and the formation of free radical and radical-radical interaction. It highlights a possible role of the HSPA8-hemin complex in exhibiting cytoprotective function during pathological conditions like malaria, sickle cell disease, etc.


Assuntos
Heme , Hemina , Hemina/química , Hemina/metabolismo , Heme/química , Peróxido de Hidrogênio , Polimerização , Peroxidases
15.
Biol Trace Elem Res ; 202(3): 927-940, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37440118

RESUMO

Zirconia nanoparticles are used in various industrial and biomedical applications such as dental implants, thermal barrier sprays, and fuel cells. The interaction of nanoparticles with the environment and humans is inevitable. Despite the enormous application potential of these nanoparticles, there are still some gaps in the literature regarding potential toxicological mechanisms and the genotoxicity of zirconia nanoparticles. The lung is one of the main exposure routes to nanomaterials; therefore, the present study was designed to determine the genotoxic and mutagenic effect of zirconia NPs in V-79 lung cells. Zirconia nanoparticles showed significant internalization in cells at 100 µg/mL and 150 µg/mL concentrations. Zirconia nanoparticles showed low cytotoxicity and were found to generate ROS in V-79 cells. In alkaline comet assay, zirconia nanoparticles (10 µg/mL, 50 µg/mL, and 100 µg/mL) exposed cells exhibited significant DNA strand breaks, while the neutral comet assay, which was used for double-strand break assessment, only revealed significant damage at 100 µg/mL. Chromosomal aberration induced by zirconia nanoparticles mainly resulted in the generation of gaps, few fragments, and breaks which signifies the low clastogenic activity of these nanoparticles in the V-79 cell line. In MN assay, zirconia nanoparticles resulted in no significant micronuclei induction at any given concentration. In the HPRT mutation assay, the particle shows a dose-dependent increase in the mutant frequency. It is evident from the result that zirconia nanoparticles cause dose-dependent cytotoxicity and genotoxicity, but still, more studies are needed to evaluate the clastogenic potential and the possible mechanism involved.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Zircônio , Humanos , Mutagênicos/toxicidade , Testes para Micronúcleos , Dano ao DNA , Nanopartículas/toxicidade , Ensaio Cometa , Nanopartículas Metálicas/toxicidade
16.
Vector Borne Zoonotic Dis ; 23(3): 113-118, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36827423

RESUMO

Objective: Tribal malaria is well known for its substantial share in the overall malarial load of the country. This paper examines the levels and trends of malaria incidence and mortality in the tribal population for the past two decades. Methods: Data on malaria incidence and mortality were collected from an online e-repository that provides statistical data and information on 19 sectors, including health. Results: The analysis showed that the malaria incidence and mortality in tribal-dominated regions declined at an average annual rate of 4.3% per annum between 2000 and 2020, which accompanies the tremendous progress made in malaria control at the country level during this time period. The results also showed that between 2016 and 2020, the decline in tribal-dominated regions was consistent and noteworthy in terms of magnitude, a period that marks the implementation of the national framework for malaria elimination in the country. Conclusion: The decisive fall in the incidence and mortality of malaria in the tribal-dominated region has put India on track to achieve the target of 3.3 of the Sustainable Development Goals. However, with the pandemic impacting service delivery, monitoring, and reporting, including malaria control programs, it is important to maintain the momentum of progress in malaria control.


Assuntos
Malária , Animais , Incidência , Malária/epidemiologia , Malária/veterinária , Índia/epidemiologia
17.
Environ Sci Pollut Res Int ; 30(14): 39708-39723, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36598724

RESUMO

The current study projects the increase in surface temperature and CO2 emissions using the EGM (1,1, α, θ) grey model for the six most significant CO2 contributing countries, namely China, the USA, India, Russia, Japan, and Germany. The study uses time series data for surface temperature (in degree celsius) from 2010 to 2020, and CO2 emission (metric tons per capita) data from 2009 to 2019. The empirical results show a downward trend in CO2 emissions from Japan, Germany, the USA, and Russia by 2028. However, in the same time period, CO2 emissions are expected to increase for India and remain nearly constant for China. This study indicates an increase in surface temperature at a significant rate in all the 6 countries: by 6.70 °C for China, 7.52 °C for Germany, 2.95 °C for India, 2.66 °C for Japan, 3.61 °C for Russia, and 13.48 °C for the USA by the end of 2028. The study compares the EGM (1,1, α, θ) grey model with the general EGM (1,1) grey model and finds that the EGM (1,1, α, θ) model performs better in both in-sample and out-of-sample forecasting. The paper also puts forward policy suggestions to mitigate, manage, and reduce increases in surface temperature as well as CO2 emissions.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Dióxido de Carbono/análise , Temperatura , China , Índia , Japão
18.
Environ Sci Pollut Res Int ; 30(3): 8188-8206, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36053427

RESUMO

Renewable energy delivers reliable power supplies and fuel diversification, enhancing energy security and lowering fuel spill risk. Renewable energy also helps conserve the nation's natural resources. Solar and other renewable energy sources have become increasingly prominent in recent years. India has achieved the 20 GW capacity solar energy production target before 2022. It is presently producing the lowest-cost solar power at the global level. Thermal energy has dominated the energy market. Countries have decided on energy generation from renewable sources and adopting green energy. This study forecasted non-renewable and renewable energy from multiple sources (hydropower, solar, wind and bioenergy) using grey forecasting model DGM (1,1,α). The comparative analyses with the classical models DGM (1,1) and EGM (1,1) revealed the superiority of the DGM (1,1,α). We also used CAGR for 2009-2019 to compare the actual and predicted data growth rate. The results show that non-renewable and renewable energy production is expected to increase. However, renewable energy generation wind sources continue to increase faster than hydropower, solar and bioenergy.


Assuntos
Energia Renovável , Energia Solar , Vento , Fontes de Energia Elétrica , Índia
19.
Environ Sci Pollut Res Int ; 30(59): 123039-123054, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37980320

RESUMO

Plastic pollution has become a prominent and pressing environmental concern within the realm of pollution. In recent times, microplastics have entered our ecosystem, especially in freshwater. In the contemporary global landscape, there exists a mounting apprehension surrounding the manifold environmental and public health issues that have emerged as a result of the substantial accumulation of microplastics. The objective of the current study is to employ an enhanced grey prediction model in order to forecast global plastic production and microplastic emissions. This study compared the accuracy level of the four grey prediction models, namely, EGM (1,1, α, θ), DGM (1,1), EGM (1,1), and DGM (1,1, α) models, to evaluate the accuracy levels. As per the estimation of the study, DGM (1,1, α) was found to be more suitable with higher accuracy levels to predict microplastic emission. The EGM (1,1, α, θ) model has slightly better accuracy than the DGM (1,1, α) model in predicting global plastic production. Various accuracy measurement tools (MAPE and RMSE) were used to determine the model's efficiency. There has been a gradual growth in both plastic production and microplastic emission. The current study using the DGM (1,1, α) model predicted that microplastic emission would be 1,084,018 by 2030. The present study aims to provide valuable insights for policymakers in formulating effective strategies to address the complex issues arising from the release of microplastics into the environment and the continuous production of plastic materials.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Poluição Ambiental , Plásticos , Poluentes Químicos da Água/análise
20.
Environ Sci Pollut Res Int ; 29(17): 25461-25472, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34841483

RESUMO

This paper compares four prediction methods, namely random forest regressor (RFR), SARIMAX, Holt-Winters (H-W), and the support vector regression (SVR), to forecast the total CO2 emission from the paddy crop in India. The major objective of this study is to compare these four models and suggest an effective model for the prediction of total CO2 emission. Data from 1961 to 2018 has been categorised into two parts: training and test data. The study forecasts total CO2 emission from paddy crops in India from 2019 to 2025. A comparison of mean absolute percentage error (MAPE) and the mean square error (MSE) highlights the differences in accuracy among the four models. The mean absolute percentage eror (MAPE) and the mean square error (MSE) for the four methods are RFR (MAPE: 5.67; MSE: 549,900.02), SARIMAX (MAPE: 1.67; MSE:70,422.35), H-W (MAPE:0.75; MSE:16,648.58), and SVR (MAPE: 0.91; MSE: 17,832.4). The values of MAPE and MSE with the Holt-Winters (H-W) and the support vector regression (SVR) are relatively low as compared to SARIMAX and RFR. Based on these results, it can be inferred that H-W and SVR were found suitable models to forecast the total CO2 emission from paddy crops. Holt-Winters model predicted 14,364.97 for the year 2025, and SVR predicted 13,696.67 for the year 2025. The decision-maker can use these predictions to build a suitable policy for the future. This approach can be contrasted with other forecasting methods, such as the neural network, and train the model to achieve better forecast accuracy.


Assuntos
Dióxido de Carbono , Modelos Estatísticos , Previsões , Índia , Redes Neurais de Computação
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