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1.
J Environ Manage ; 307: 114520, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35066193

RESUMO

Greenhouse gas (GHG) emissions from agriculture sector play an important role for global warming and climate change. Thus, it is necessary to find out GHG emissions mitigation strategies from rice cultivation. The efficient management of nitrogen fertilizer using urea deep placement (UDP) and the use of the water-saving alternate wetting and drying (AWD) irrigation could mitigate greenhouse gas (GHG) emissions and reduce environmental pollution. However, there is a dearth of studies on the impacts of UDP and the integrated plant nutrient system (IPNS) which combines poultry manure and prilled urea (PU) with different irrigation regimes on GHG emissions, nitrogen use efficiency (NUE) and rice yields. We conducted field experiments during the dry seasons of 2018, 2019, and 2020 to compare the effects of four fertilizer treatments including control (no N), PU, UDP, and IPNS in combination with two irrigation systems- (AWD and continuous flooding, CF) on GHG emissions, NUE and rice yield. Fertilizer treatments had significant (p < 0.05) interaction effects with irrigation regimes on methane (CH4) and nitrous oxide (N2O) emissions. PU reduced CH4 and N2O emissions by 6% and 20% compared to IPNS treatment, respectively under AWD irrigation, but produced similar emissions under CF irrigation. Similarly, UDP reduced cumulative CH4 emissions by 9% and 15% under AWD irrigation, and 9% and 11% under CF condition compared to PU and IPNS treatments, respectively. Across the year and fertilizer treatments, AWD irrigation significantly (p < 0.05) reduced cumulative CH4 emissions and GHG intensity by 28%, and 26%, respectively without significant yield loss compared to CF condition. Although AWD irrigation increased cumulative N2O emissions by 73%, it reduced the total global warming potential by 27% compared to CF irrigation. The CH4 emission factor for AWD was lower (1.67 kg ha-1 day-1) compared to CF (2.33 kg ha-1 day-1). Across the irrigation regimes, UDP increased rice yield by 21% and N recovery efficiency by 58% compared to PU. These results suggest that both UDP and AWD irrigation might be considered as a carbon-friendly technology.


Assuntos
Gases de Efeito Estufa , Oryza , Agricultura , Fertilizantes/análise , Gases de Efeito Estufa/análise , Metano/análise , Óxido Nitroso/análise , Solo , Água , Abastecimento de Água
2.
Ecotoxicol Environ Saf ; 200: 110756, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32464442

RESUMO

Arsenic is a recognized highly toxic contaminant, responsible for numerous human diseases and affecting many millions of people in different parts of the world. Contrarily, curcumin is a natural dietary polyphenolic compound and the main active ingredient in turmeric. Recently it has drawn great attention due to its diverse biological activities, strong antioxidant properties and therapeutic potential against many human ailments. In this study, we aimed to explore the protective effects and the regulatory role of curcumin on arsenic-induced toxicity and gain insights into biomolecular mechanism/s. Arsenic (10 µM) treatment in PC12 cells for 24 h induced cytotoxicity by decreasing cell viability and intracellular glutathione level and increasing lactate dehydrogenase activity and DNA fragmentation. In addition, arsenic caused apoptotic cell death in PC12 cells, which were confirmed from flow cytometry results. Moreover, arsenic (10 µM) treatment significantly down-regulated the inhibition factors of autophagy/apoptosis; mTOR, Akt, Nrf2, ERK1, Bcl-x, Xiap protein expressions, up-regulated the enhanced factors of autophagy/apoptosis; ULK, LC3, p53, Bax, cytochrome c, caspase 9, cleaved caspase 3 proteins and eventually caused autophagic and apoptotic cell death. However, curcumin (2.5 µM) pretreatment with arsenic (10 µM) effectively saves PC12 cells against arsenic-induced cytotoxicity through increasing cell viability, intracellular GSH level and boosting the antioxidant defense system, and limiting the LDH activity and DNA damage. Furthermore, pretreatment of curcumin with arsenic expressively alleviated arsenic-induced toxicity and cell death by reversing the expressions of proteins; mTOR, Akt, Nrf2, ERK1, Bcl-x, Xiap, ULK, LC3, p53, Bax, cytochrome c, caspase 9 and cleaved caspase 3. Our findings indicated that curcumin showed antioxidant properties through the Nrf2 antioxidant signaling pathway and alleviates arsenic-triggered toxicity in PC12 cells by regulating autophagy/apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Arsênio/toxicidade , Autofagia/efeitos dos fármacos , Curcumina/farmacologia , Poluentes Ambientais/toxicidade , Animais , Antioxidantes/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Glutationa/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos
3.
Int J Mol Sci ; 21(21)2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33171928

RESUMO

Nonthermal, biocompatible plasma (NBP) is a promising unique state of matter that is effective against a wide range of pathogenic microorganisms. This study focused on a sterilization method for bacteria that used the dielectric barrier discharge (DBD) biocompatible plasma cabinet sterilizer as an ozone generator. Reactive oxygen species play a key role in inactivation when air or other oxygen-containing gases are used. Compared with the untreated control, Escherichia coli(E. coli), Staphylococcus aureus (S. aureus), and Salmonella typhimurium (sepsis) were inhibited by approximately 99%, or were nondetectable following plasma treatment. Two kinds of plasma sterilizers containing six- or three-chamber cabinets were evaluated. There was no noticeable difference between the two configurations in the inactivation of microorganisms. Both cabinet configurations were shown to be able to reduce microbes dramatically, i.e., to the nondetectable range. Therefore, our data indicate that the biocompatible plasma cabinet sterilizer may prove to be an appropriate alternative sterilization procedure.


Assuntos
Gases em Plasma/farmacologia , Esterilização/instrumentação , Esterilização/métodos , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Materiais Biocompatíveis , Desinfecção/instrumentação , Desinfecção/métodos , Escherichia coli/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Oxigênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
4.
Ecotoxicol Environ Saf ; 168: 146-163, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30384162

RESUMO

Metals are ubiquitous in the environment due to huge industrial applications in the form of different chemicals and from extensive mining activities. The frequent exposures to metals and metalloids are crucial for the human health. Trace metals are beneficial for health whereas non-essential metals are dangerous for the health and some are proven etiological factors for diseases including cancers and neurological disorders. The interactions of essential trace metals such as selenium (Se) and zinc (Zn) with non-essential metals viz. lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) in biological system are very critical and complex. A huge number of studies report the protective role of Se and Zn against metal toxicity, both in animal and cellular levels, and also explain the numerous mechanisms involved. However, it has been considered that a tiny dyshomeostasis in the metals/trace metals status in biological system could induce severe deleterious effects that can manifest to numerous diseases. Thus, in this particular review, we have demonstrated the critical protection mechanism/s of Se and Zn against Cd, Pb, As and Hg toxicity in a one by one manner to clarify the up-to-date findings and perspectives. Furthermore, biomolecular consequences are comprehensively presented in light of particular cellular/biomolecular events which are somehow linked to a subsequent disease. The analyzed reports support significant protection potential of Se and Zn, either alone or in combination with other agents, against each of the abovementioned non-essential metals. However, Se and Zn are still not being used as detoxifying agents due to some unexplained reasons. We hypothesized that Se could be a potential candidate for detoxifying As and Hg regardless of their chemical speciations, but requires intensive clinical trials. However, particularly Zn-Hg interaction warrants more investigations both in animal and cellular level.


Assuntos
Substâncias Protetoras/farmacologia , Selênio/farmacologia , Zinco/farmacologia , Animais , Arsênio/toxicidade , Cádmio/toxicidade , Exposição Ambiental/efeitos adversos , Humanos , Chumbo/toxicidade , Mercúrio/toxicidade , Metais Pesados/toxicidade , Modelos Animais , Saúde Pública , Oligoelementos/farmacologia
5.
Trop Med Int Health ; 23(1): 26-33, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121442

RESUMO

OBJECTIVE: To investigate the relationship between faecal contamination in child play spaces, enteric infections, environmental enteropathy (EE) and impaired growth among young children. METHODS: A prospective cohort study was conducted of 203 children 6-30 months of age in rural Bangladesh. Stool samples were analysed by quantitative PCR for Shigella, Enterotoxigenic Escherichia coli (ETEC), Campylobacter jejuni, Giardia intestinalis and Cryptosporidium spp. Four faecal markers of intestinal inflammation were also measured: alpha-1-antitrypsin, myeloperoxidase, neopterin and calprotectin. Child growth was measured at baseline and 9 months after enrolment. E. coli was measured in soil in child play spaces. RESULTS: Forty-seven percent of study children had three or more enteric pathogens in their stool. Thirty five percent (71/203) of children had Shigella, 30% (61/203) had ETEC, 73% (148/203) had C. jejuni, 79% (160/203) had Giardia intestinalis and none had Cryptosporidium. Children with ETEC had significantly higher calprotectin concentrations (Coefficient: 1.35, 95% Confidence Interval [CI]: 1.005, 1.82). Children with Shigella had a significantly higher odds of being stunted at our 9-month follow-up (OR: 2.01, 95% CI: 1.02, 3.93). Children with Giardia intestinalis had significantly higher E.coli counts in the soil collected from their play spaces (OR: 1.23, 95% CI: 1.02, 1.48). CONCLUSION: Enteric infections were significantly associated with EE and impaired growth in rural Bangladesh. These findings provide further evidence to support the hypothesis that contaminated soil in child play spaces can lead to enteric infections, many of which are likely subclinical, resulting in EE and impaired growth in young children.


Assuntos
Deficiências do Desenvolvimento/etiologia , Diarreia/etiologia , Exposição Ambiental/efeitos adversos , Jogos e Brinquedos , Microbiologia do Solo , Pré-Escolar , Deficiências do Desenvolvimento/microbiologia , Diarreia/microbiologia , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Solo
6.
Trop Med Int Health ; 22(6): 670-678, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28319300

RESUMO

OBJECTIVE: To characterise childhood mouthing behaviours and to investigate the association between object-to-mouth and food-to-mouth contacts, diarrhoea prevalence and environmental enteropathy. METHODS: A prospective cohort study was conducted of 216 children ≤30 months of age in rural Bangladesh. Mouthing contacts with soil and food and objects with visible soil were assessed by 5-h structured observation. Stool was analysed for four faecal markers of intestinal inflammation: alpha-1-antitrypsin, myeloperoxidase, neopterin and calprotectin. RESULTS: Overall 82% of children were observed mouthing soil, objects with visible soil, or food with visible soil during the structured observation period. Sixty two percent of children were observed mouthing objects with visible soil, 63% were observed mouthing food with visible soil, and 18% were observed mouthing soil only. Children observed mouthing objects with visible soil had significantly elevated faecal calprotectin concentrations (206.81 µg/g, 95% confidence interval [CI]: 6.27, 407.36). There was also a marginally significant association between Escherichia coli counts in soil from a child's play space and the prevalence rate of diarrhoea (diarrhoea prevalence ratio: 2.03, 95% CI 0.97, 4.25). CONCLUSION: These findings provide further evidence to support the hypothesis that childhood mouthing behaviour in environments with faecal contamination can lead to environmental enteropathy in susceptible paediatric populations. Furthermore, these findings suggest that young children mouthing objects with soil, which occurred more frequently than soil directly (60% vs. 18%), was an important exposure route to faecal pathogens and a risk factor for environmental enteropathy.


Assuntos
Comportamento Infantil , Diarreia/etiologia , Exposição Ambiental/efeitos adversos , Inflamação/etiologia , Enteropatias/etiologia , Boca , Solo , Bangladesh/epidemiologia , Pré-Escolar , Diarreia/epidemiologia , Diarreia/microbiologia , Escherichia coli , Fezes/química , Feminino , Humanos , Lactente , Inflamação/metabolismo , Enteropatias/patologia , Mucosa Intestinal/metabolismo , Intestinos/microbiologia , Intestinos/patologia , Complexo Antígeno L1 Leucocitário/metabolismo , Masculino , Jogos e Brinquedos , Estudos Prospectivos , População Rural , Microbiologia do Solo
7.
Artigo em Inglês | MEDLINE | ID: mdl-26521522

RESUMO

The microbiological quality of street vended food samples from Dhaka, Bangladesh was evaluated. The objective of the study was to identify the presence of common pathogens (Escherichia coli, Shigella spp, Salmonella and Vibrio spp) and to describe the molecular characterization of E coli, a commonly found pathogen in various street foods. Fifty food samples were collected from fixed and mobile vendors from two sampling locations (Mohakhali and Aftabnagar) in Dhaka city, Bangladesh. The tested samples included deep fried and fried snacks; quick lunch items; pickles; fruit chutney; baked items; spicy, sour and hot snacks etc: Juices, tamarind water and plain drinking water were also tested. Sterile polythene bags were used for collecting 200 g of each category of samples. They were tested for the presence of microorganisms following conventional microbiological processes. Biochemical tests followed by serology were done for the confirmation of Shigella and Salmonella. Serological reaction was carried out for confirmation of Vibrio spp. DNA was isolated for the molecular characterization to detect the pathogenic E. coli by polymerase chain reaction (PCR). Out of 50 food samples, six (12%) were confirmed to contain different species of E. coli and Shigella. Molecular characterization of E. coli revealed that three samples were contaminated with enteroaggregative E. coli (EAEC) and one was contaminated with enterotoxigenic E. coli (ETEC). Shigellaflexneri X variant was detected in one food item and Shigella flexneri 2a was found in drinking water. All these enteric pathogens could be the potential cause for foodborne illnesses.


Assuntos
Escherichia coli/isolamento & purificação , Contaminação de Alimentos , Microbiologia de Alimentos , Salmonella/isolamento & purificação , Shigella/isolamento & purificação , Vibrio/isolamento & purificação , Bangladesh , Escherichia coli/genética , Manipulação de Alimentos , Humanos , Reação em Cadeia da Polimerase , Universidades
8.
Polymers (Basel) ; 16(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891430

RESUMO

This paper presents an experimental investigation of nanocomposites composed of three ratios of epoxy/graphene nanoplatelets (GNPs) by weight. The 0.1, 0.2, and 0.3 wt.% specimens were carefully manufactured, and their mechanical and thermal conductivity properties were examined. The tensile strength and modulus of epoxy/GNPs were enhanced by the large surface area of graphene nanoplatelets, causing crack deflection that created new fracture fronts and friction because of the rough fracture surface. However, the compressive strength was gradually reduced as GNP loading percentages increased. This was probably due to severe plastic yielding on the epoxy, leading to catastrophic axial splitting caused by premature fractures. Furthermore, the highest thermal conductivity was 0.1283 W/m-K, representing a 20.92% improvement over neat epoxy (0.1061 W/m-K) when 0.3 wt.% GNPs were added to the epoxy. This was because of efficient heat propagation in the GNPs due to electron movement through percolative paths. The tensile failure mode in epoxy/GNP nanocomposites showed a few deflected and bifurcated rough cracks and brittle, dimple-like fractures. Contrarily, compressive failure mode in GNP-added epoxy showed plastic flexural buckling and brittle large-axial splitting. The epoxy/GNP nanocomposites were considered a damage-tolerant material.

9.
Heliyon ; 10(11): e29766, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38828360

RESUMO

Nanoparticles have recently become considered as a crucial player in contemporary medicine, with therapeutic uses ranging from contrast agents in imaging to carriers for the transport of drugs and genes into a specific target. Nanoparticles have the ability to have more precise molecular interactions with the human body in order to target specific cells and tissues with minimal adverse effects and maximal therapeutic outcomes. With the least number of side effects and the greatest possible therapeutic benefit, nanoparticles can target particular cells and tissues through more precise molecular interactions with the human body. The majority of global public health problems are now treated with green synthesized silver nanoparticles (AgNPs), which substantially affect the fundamental structure of DNA and proteins and thus display their antimicrobial action. AgNPs can inhibit the proliferation of tumor cells and induce oxidative stress. By inhibiting vascular endothelial growth factor (HIF)-1, pro-inflammatory mediators generated by silver nanoparticles are reduced, mucin hypersecretion is lessened, and gene activity is subsequently regulated to prevent infections. The biogenic synthesis of silver nanoparticles (AgNPs) using various plants and their applications in antibacterial, antifungal, antioxidant, anticancer, anti-inflammatory, and antidiabetic activities have been extensively discussed in this article. Also, because only natural substances are utilized in the manufacturing process, the particles that are created naturally are coated, stabilized, and play a vital role in these biomedical actions. The characterization of AgNPs, possibility of preparing AgNPSs with different shapes using biological method and their impact on functions and toxicities, impact of size, shape and other properties on AgNPs functions and toxicity profiles, limitations, and future prospects of green-mediated AgNPs have also been reported in this study. The major goal of this study is to provide readers with a comprehensive, informed, and up-to-date summary of the various AgNPs production and characterization methods and their under-investigational antioxidant, antibacterial, and anticancer, antidiabetic, antifungal and anti-inflammatory properties. This review provides instructions and suggestions for additional studies based on AgNPs. This evaluation also pushes researchers to look into natural resources like plant parts in order to create useful nanobiotechnology.

10.
iScience ; 26(12): 108408, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38058301

RESUMO

Canonical pyroptosis is type of programmed cell death depending on active caspase-1, and the inflammasome carries out caspase-1 activation. Here, we showed that docosahexaenoic acid (DHA) induced ovarian cancer cell deaths in caspase-1-dependent manner. DHA increased caspase-1 activity and led to interleukin-1ß secretion and gasdermin D cleavage while disulfiram inhibited DHA-induced cell death, suggesting that DHA triggered pyroptosis. Intriguingly, ASC, the molecule recruiting caspase-1 to inflammasome for activation, was dispensable for DHA-induced pyroptosis. Instead, we observed remarkable elevation in caspase-1 abundance concurrent with the activation of caspase-1 in DHA-treated cells. As ectopically overexpressing caspase-1 resulted in robust amount of active caspase-1, we reason that DHA activates caspase-1 and pyroptosis through the generation of excessive amount of caspase-1 protein. Mechanistically, DHA increased caspase-1 by specifically accelerating caspase-1 protein synthesis via the p38MAPK/Mnk1 signaling pathway. We have uncovered an unknown pyroptosis mechanism in which caspase-1-dependent pyroptosis can occur without the participation of ASC/inflammasome.

11.
IEEE J Biomed Health Inform ; 26(12): 5805-5816, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35857737

RESUMO

Federated learning methods offer secured monitor services and privacy-preserving paradigms to end-users and organisations in the Internet of Things networks such as smart healthcare systems. Federated learning has been coined to safeguard sensitive data, and its global aggregation is often based on a centralised server. This design is vulnerable to malicious attacks and could be breached by privacy attacks such as inference and free-riding, leading to inefficient training models. Besides, uploaded analysing parameters by patients can reveal private information and the threat of direct manipulation by the central server. To address these issues, we present a three-fold Federated Edge Aggregator, the so-called Edge Intelligence, a federated learning-based privacy protection framework for safeguarding Smart Healthcare Systems at the edge against such privacy attacks. We employ an iteration-based Conventional Neural Network (CNN) model and artificial noise functions to balance privacy protection and model performance. A theoretical convergence bound of Edge Intelligence on the trained federated learning model's loss function is also introduced here. We evaluate and compare the proposed framework with the recently established methods using model performance and privacy budget on popular and recent datasets: MNIST, CIFAR10, STL10, and COVID19 chest x-ray. Finally, the proposed framework achieves 90% accuracy and a high privacy rate demonstrating better performance than the baseline technique.


Assuntos
COVID-19 , Privacidade , Humanos , Fenbendazol , Inteligência , Internet
12.
PLoS One ; 17(8): e0272625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35944036

RESUMO

FOXP2 encodes the forkhead transcription factor that plays a significant role in language development. Single nucleotide polymorphisms in FOXP2 have been linked to speech- language disorder, autism, cancer and schizophrenia. So, scrutinizing the functional SNPs to better understand their association in disease is an uphill task. The purpose of the current study was to identify the missense SNPs which have detrimental structural and functional effects on the FOXP2 protein. Multiple computational tools were employed to investigate the deleterious role of non-synonymous SNPs. Five variants as Y531H, L558P, R536G and R553C were found to be associated with diseases and located at the forkhead domain of the FOXP2 protein. Molecular docking analysis of FOXP2 DNA binding domain with its most common target sequence 5'-CAAATT-3' predicted that R553C and L558P mutant variants destabilize protein structure by changing protein-DNA interface interactions and disruption of hydrogen bonds that may reduce the specificity and affinity of the binding. Further experimental investigations may need to verify whether this kind of structural and functional variations dysregulate protein activities and induce formation of disease.


Assuntos
Fatores de Transcrição Forkhead , Polimorfismo de Nucleotídeo Único , DNA/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Humanos , Simulação de Acoplamento Molecular , Domínios Proteicos
13.
J Infect Dev Ctries ; 16(12): 1835-1844, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36753649

RESUMO

INTRODUCTION: Shigella continues to cause significant morbidity and mortality each year, mostly in under-five children living in developing countries. We investigated the association between Shigella virulence genes and shigellosis. METHODOLOGY: We randomly selected 61 S. flexneri strains isolated from patients in Bangladesh between 2009 and 2013, and evaluated the presence of 140 MDa large-virulence-plasmid (p140), and 22 virulence genes including ipaH, ial, toxin, and T3SS-related genes. RESULTS: We found p140 in 79% (n = 48) and ipaBCD in 90% (n = 55) strains, while seven strains were missing the p140. The prevalence of ial was 89%, ipgC and ipgE was 85%, and the prevalence for the remaining genes was < 85%. During the multivariate analysis, we found that instead of sen, the Shigella enterotoxin gene set along with several other virulence genes such as ipgA, icsB, ipgB1, spa15, and mxiC, were significantly influencing multiple clinical features relevant to shigellosis, including bloody stool, mucoid stool, and rectal straining. CONCLUSIONS: We believe our model will help to determine the actual disease burden by directly looking for the genetic material in clinically suggestive patients, especially when detecting the causative organisms by traditional means is difficult.


Assuntos
Disenteria Bacilar , Shigella , Humanos , Disenteria Bacilar/epidemiologia , Disenteria Bacilar/diagnóstico , Plasmídeos , Shigella/genética , Shigella flexneri/genética , Virulência/genética , Fatores de Virulência/genética
14.
Cells ; 10(2)2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530311

RESUMO

Glioblastoma multiforme (GBM) is a highly malignant and rapidly advancing astrocytic brain tumor in adults. Current therapy possibilities are chemotherapy, surgical resection, and radiation. The complexity of drug release through the blood-brain barrier, tumor reaction to chemotherapy, and the inherent resistance of tumor cells present challenges. New therapies are needed for individual use or combination with conventional methods for more effective treatment and improved survival for patients. GBM is difficult to treat because it grows quickly, spreads finger-shaped tentacles, and creates an irregular margin of normal tissue surrounding the tumor. Non-thermal biocompatible plasma (NBP) has recently been shown to selectively target cancer cells with minimal effects on regular cells, acting by generating reactive oxygen species (ROS) and reactive nitrogen species (RNS). We applied a soft jet plasma device with a syringe shape to U87 MG cells and astrocytes. Our results show that NBP-J significantly inhibits cell proliferation and changes morphology, induces cell cycle arrest, inhibits the survival pathway, and induces apoptosis. Our results indicate that NBP-J may be an efficient and safe clinical device for brain cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Neoplasias Encefálicas/patologia , Gases em Plasma/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo
15.
Biol Trace Elem Res ; 199(9): 3272-3286, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33236292

RESUMO

Green synthesized silver nanoparticles (Ag-NPs) have demonstrated promising effects, including cytotoxicity and anticancer potential, in different cell lines. Therefore, in our previous study, Ag-NPs were synthesized from the reduction of AgNO3 using Brassica rapa var. japonica (Bj) leaf extract as a reducing and stabilizing agent. The synthesized Ag-NPs were spherical in shape, with a size range of 15-30 nm. They had phase-centered cubic structure with strong growth inhibition potential against some bacteria. In continuation with our previous study, in the present study, we aimed to investigate the autophagy-regulated cytotoxic effect of Ag-NPs against human epithelial colorectal adenocarcinoma cells (Caco-2 cells). We found that the Bj leaf aqueous extract facilitated Brassica silver nanoparticles (Brassica Ag-NPs)-induced NF-κB mediated autophagy in Caco-2 cells. Results showed that Ag-NPs reduced cell viability of Caco-2 cells by inducing oxidative stress and DNA damage. Therefore, to understand the mechanism underlying the death-promoting activity of Ag-NPs in Caco-2 cells, western blotting was performed. Western blot analysis showed decreased expression of NFκB and increased expression of IκB, which is a sign of autophagy initiation. In addition, autophagosome formation was accelerated by the activity of p53 and light chain 3 (LC3) II. In addition, inhibition of Akt and mTOR also played a pivotal role in autophagy formation. Finally, excessive expansion of autophagy promoted apoptosis, which subsequently resulted in necrosis. These findings support a novel cell death-promoting function of autophagy by Ag-NPs in Caco-2 cells.


Assuntos
Neoplasias Colorretais , Nanopartículas Metálicas , Apoptose , Autofagia , Células CACO-2 , Neoplasias Colorretais/tratamento farmacológico , Humanos , NF-kappa B , Prata/farmacologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-33671655

RESUMO

α-Lipoic acid (ALA) and its reduced form dihydrolipoic acid (DHLA) are endogenous dithiol compounds with significant antioxidant properties, both of which have the potential to detoxify cells. In this study, ALA (250 µM) and DHLA (50 µM) were applied to reduce metal (As, Cd, and Pb)-induced toxicity in PC12 and Caco-2 cells as simultaneous exposure. Both significantly decreased Cd (5 µM)-, As (5 µM)-, and Pb (5 µM)-induced cell death. Subsequently, both ALA and DHLA restored cell membrane integrity and intracellular glutathione (GSH) levels, which were affected by metal-induced toxicity. In addition, DHLA protected PC12 cells from metal-induced DNA damage upon co-exposure to metals. Furthermore, ALA and DHLA upregulated the expression of survival-related proteins mTOR (mammalian target of rapamycin), Akt (protein kinase B), and Nrf2 (nuclear factor erythroid 2-related factor 2) in PC12 cells, which were previously downregulated by metal exposure. In contrast, in Caco-2 cells, upon co-exposure to metals and ALA, Nrf2 was upregulated and cleaved PARP-1 (poly (ADP-ribose) polymerase-1) was downregulated. These findings suggest that ALA and DHLA can counterbalance the toxic effects of metals. The protection of ALA or DHLA against metal toxicity may be largely due to an enhancement of antioxidant defense along with reduced glutathione level, which ultimately reduces the cellular oxidative stress.


Assuntos
Ácido Tióctico , Animais , Antioxidantes , Células CACO-2 , Humanos , Estresse Oxidativo , Células PC12 , Ratos , Ácido Tióctico/análogos & derivados , Ácido Tióctico/farmacologia
17.
Front Microbiol ; 12: 613529, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868187

RESUMO

Antimicrobial resistance (AMR) is a major problem globally. The main bacterial organisms associated with urinary tract infection (UTI) associated sepsis are E. coli and Klebsiella along with Enterobacter species. These all have AMR strains known as ESBL (Extended Spectrum Beta-Lactamase), which are featured on the WHO priority pathogens list as "critical" for research. Bacteriophages (phages), as viruses that can infect and kill bacteria, could provide an effective tool to tackle these AMR strains. There is currently no "gold standard" for developing a phage cocktail. Here we describe a novel approach to develop an effective phage cocktail against a set of ESBL-producing E. coli and Klebsiella largely isolated from patients in United Kingdom hospitals. By comparing different measures of phage efficacy, we show which are the most robust, and suggest an efficient screening cascade that could be used to develop phage cocktails to target other AMR bacterial species. A target panel of 38 ESBL-producing clinical strains isolated from urine samples was collated and used to test phage efficacy. After an initial screening of 68 phages, six were identified and tested against these 38 strains to determine their clinical coverage and killing efficiency. To achieve this, we assessed four different methods to assess phage virulence across these bacterial isolates. These were the Direct Spot Test (DST), the Efficiency of Plating (EOP) assay, the planktonic killing assay (PKA) and the biofilm assay. The final ESBL cocktail of six phages could effectively kill 23/38 strains (61%), for Klebsiella 13/19 (68%) and for E. coli 10/19 (53%) based on the PKA data. The ESBL E. coli collection had six isolates from the prevalent UTI-associated ST131 sequence type, five of which were targeted effectively by the final cocktail. Of the four methods used to assess phage virulence, the data suggests that PKAs are as effective as the much more time-consuming EOPs and data for the two assays correlates well. This suggests that planktonic killing is a good proxy to determine which phages should be used in a cocktail. This assay when combined with the virulence index also allows "phage synergy" to inform cocktail design.

18.
Cancers (Basel) ; 12(1)2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31963881

RESUMO

Nonthermal plasma is a promising novel therapy for the alteration of biological and clinical functions of cells and tissues, including apoptosis and inhibition of tumor progression. This therapy generates reactive oxygen and nitrogen species (RONS), which play a major role in anticancer effects. Previous research has verified that plasma jets can selectively induce apoptosis in various cancer cells, suggesting that it could be a potentially effective novel therapy in combination with or as an alternative to conventional therapeutic methods. In this study, we determined the effects of nonthermal air soft plasma jets on a U87 MG brain cancer cell line, including the dose- and time-dependent effects and the physicochemical and biological correlation between the RONS cascade and p38/mitogen-activated protein kinase (MAPK) signaling pathway, which contribute to apoptosis. The results indicated that soft plasma jets efficiently inhibit cell proliferation and induce apoptosis in U87 MG cells but have minimal effects on astrocytes. These findings revealed that soft plasma jets produce a potent cytotoxic effect via the initiation of cell cycle arrest and apoptosis. The production of reactive oxygen species (ROS) in cells was tested, and an intracellular ROS scavenger, N-acetyl cysteine (NAC), was examined. Our results suggested that soft plasma jets could potentially be used as an effective approach for anticancer therapy.

19.
Sci Total Environ ; 734: 139382, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32460078

RESUMO

Alternate wetting and drying (AWD) irrigation in lowland rice cultivation increases water use efficiency and could reduce greenhouse gas (GHG) emissions compared to the farmers' practice of continuous flooding (CF). However, there is a dearth of studies on the impacts of water management on methane (CH4) and nitrous oxide (N2O) emissions in Bangladesh. Multi-location field experiments were conducted during the dry seasons of 2018 and 2019 to determine the baseline emissions of CH4 and N2O from rice fields and compare the emissions from AWD irrigation and CF. CH4 and N2O emissions were measured using the closed chamber technique and their concentrations were determined using a gas chromatograph. CH4 and N2O emissions varied across water management schemes and sites. AWD irrigation significantly (p < 0.05) reduced cumulative CH4 emissions (37%, average across sites) without affecting grain yields compared to CF. The CH4 emission factor for AWD was lower (1.39 kg ha-1 day-1) compared to CF (2.21 kg ha-1 day-1). Although AWD irrigation increased seasonal cumulative N2O emissions by 46%, it did not offset reduced CH4 emissions. AWD reduced the total global warming potential (GWP) by 36% compared to CF. Similarly, GHG intensity (GHGI) in AWD was 34% smaller compared to that in CF. Emissions varied across sites and the magnitudes of seasonal cumulative CH4 and N2O emissions were higher at the Gazipur site compared to the Mymensingh site. AWD, which saves irrigation water without any yield penalty, could be considered a promising strategy to mitigate GHG emissions from rice fields in Bangladesh.

20.
Environ Toxicol Pharmacol ; 74: 103302, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31786496

RESUMO

Arsenic is awfully toxic metalloid responsible for many human diseases all over the world. Contrastingly, D-pinitol is a naturally occurring bioactive dietary compound has antioxidant properties. The objective of this study is to elucidate the protective actions of D-pinitol on arsenic-induced cytotoxicity and explore its controlling role in biomolecular mechanisms in PC12 cells. Obtained results demonstrated that co-exposure of D-pinitol with arsenic increases cell viability, decreases DNA damage and protects PC12 cells from arsenic-induced cytotoxicity by increasing glutathione (GSH) level and glutathione reductase (GR). Protein expression of western blot analysis showed that co-exposure of D-pinitol and arsenic significantly inhibited arsenic-induced autophagy which further suppressed apoptosis through up-regulation of survival factors; mTOR, p-mTOR, Akt, p-Akt, NF-кB, Nrf2, ERK1, GR, Bcl-x and down-regulation of death factors; p53, Bax, cytochrome c, LC3, although arsenic regulated those factors negatively. These results of this study suggested that D-pinitol protects PC12 cells from arsenic-induced cytotoxicity.


Assuntos
Arsênio/toxicidade , Inositol/análogos & derivados , Substâncias Protetoras/farmacologia , Animais , Autofagia , Sobrevivência Celular , Glutationa , Humanos , Inositol/farmacologia , Células PC12 , Ratos
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