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1.
Arch Microbiol ; 206(4): 134, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38433145

RESUMO

Acanthamoeba castellanii are opportunistic pathogens known to cause infection of the central nervous system termed: granulomatous amoebic encephalitis, that mostly effects immunocompromised individuals, and a sight threatening keratitis, known as Acanthamoeba keratitis, which mostly affects contact lens wearers. The current treatment available is problematic, and is toxic. Herein, an amphiphilic star polymer with AB2 miktoarms [A = hydrophobic poly(ℇ-Caprolacton) and B = hydrophilic poly (ethylene glycol)] was synthesized by ring opening polymerization and CuI catalyzed azide-alkyne cycloaddition. Characterization by 1H and 13C NMR spectroscopy, size-exclusion chromatography and fluorescence spectroscopy was accomplished. The hydrophobic drug itraconazole (ITZ) was incorporated in self-assembled micellar structure of AB2 miktoarms through co-solvent evaporation. The properties of ITZ loaded (ITZ-PCL-PEG2) and blank micelles (PCL-PEG2) were investigated through zeta sizer, scanning electron microscopy and Fourier-transform infrared spectroscopy. Itraconazole alone (ITZ), polymer (DPB-PCL), empty polymeric micelles (PCL-PEG2) alone, and itraconazole loaded in polymeric micelles (ITZ-PCL-PEG2) were tested for anti-amoebic potential against Acanthamoeba, and the cytotoxicity on human cells were determined. The polymer was able to self-assemble in aqueous conditions and exhibited low value for critical micelle concentration (CMC) 0.05-0.06 µg/mL. The maximum entrapment efficiency of ITZ was 68%. Of note, ITZ, DPB, PCL-PEG2 and ITZ-PCL-PEG2 inhibited amoebae trophozoites by 37.34%, 36.30%, 35.77%, and 68.24%, respectively, as compared to controls. Moreover, ITZ-PCL-PEG2 revealed limited cytotoxicity against human keratinocyte cells. These results are indicative that ITZ-PCL-PEG2 micelle show significantly better anti-amoebic effects as compared to ITZ alone and thus should be investigated further in vivo to determine its clinical potential.


Assuntos
Acanthamoeba castellanii , Micelas , Humanos , Itraconazol/farmacologia , Alcinos , Polímeros
2.
Biometals ; 37(1): 171-184, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37792257

RESUMO

The development of antibiotic alternatives that entail distinctive chemistry and modes of action is necessary due to the threat posed by drug resistance. Nanotechnology has gained increasing attention in recent years, as a vehicle to enhance the efficacy of existing antimicrobials. In this study, Chitosan copper oxide nanoparticles (CHI-CuO) were synthesized and were further loaded with Quercetagetin (QTG) to achieve the desired (CHI-CuO-QTG). Size distribution, zeta potential and morphological analysis were accomplished. Next, the developed CHI-CuO-QTG was assessed for synergistic antibacterial properties, as well as cytotoxic attributes. Bactericidal assays revealed that CHI-CuO conjugation showed remarkable effects and enhanced QTG effects against a range of Gram + ve and Gram - ve bacteria. The MIC50 of QTG against S. pyogenes was 107 µg/mL while CHI-CuO-QTG reduced it to 9 µg/mL. Similar results were observed when tested against S. pneumoniae. Likewise, the MIC50 of QTG against S. enterica was 38 µg/mL while CHI-CuO-QTG reduced it to 7 µg/mL. For E. coli K1, the MIC50 of QTG was 42 µg/mL while with CHI-CuO-QTG it was 23 µg/mL. Finally, the MIC50 of QTG against S. marcescens was 98 µg/mL while CHI-CuO-QTG reduced it to 10 µg/mL. Notably, the CHI-CuO-QTG nano-formulation showed limited damage when tested against human cells using lactate dehydrogenase release assays. Importantly, bacterial-mediated human cell damage was reduced by prior treatment of bacteria using drug nano-formulations. These findings are remarkable and clearly demonstrate that drug-nanoparticle formulations using nanotechnology is an important avenue in developing potential therapeutic interventions against microbial infections.


Assuntos
Quitosana , Flavonas , Nanopartículas Metálicas , Nanopartículas , Humanos , Quitosana/farmacologia , Quitosana/química , Cobre/farmacologia , Cobre/química , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Óxidos , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana
3.
Biometals ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38705945

RESUMO

With the emergence of drug-resistance, there is a need for novel anti-bacterials or to enhance the efficacy of existing drugs. In this study, Patuletin (PA), a flavanoid was loaded onto Gallic acid modified Zinc oxide nanoparticles (PA-GA-ZnO), and evaluated for antibacterial properties against Gram-positive (Bacillus cereus and Streptococcus pneumoniae) and Gram-negative (Samonella enterica and Escherichia coli) bacteria. Characterization of PA, GA-ZnO and PA-GA-ZnO' nanoparticles was accomplished utilizing fourier-transform infrared spectroscopy, efficiency of drug entrapment, polydispersity index, zeta potential, size, and surface morphology analysis through atomic force microscopy. Using bactericidal assays, the results revealed that ZnO conjugation displayed remarkable effects and enhanced Patuletin's effects against both Gram-positive and Gram-negative bacteria, with the minimum inhibitory concentration observed at micromolar concentrations. Cytopathogenicity assays exhibited that the drug-nanoconjugates reduced bacterial-mediated human cell death with minimal side effects to human cells. When tested alone, drug-nanoconjugates tested in this study showed limited toxic effects against human cells in vitro. These are promising findings, but future work is needed to understand the molecular mechanisms of effects of drug-nanoconjugates against bacterial pathogens, in addition to in vivo testing to determine their translational value. This study suggests that Patuletin-loaded nano-formulation (PA-GA-ZnO) may be implicated in a multi-target mechanism that affects both Gram-positive and Gram-negative pathogen cell structures, however this needs to be ascertained in future work.

4.
Environ Res ; 252(Pt 1): 118862, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574984

RESUMO

The escalating issue of air pollution has become a significant concern in urban regions, including Islamabad, Pakistan, due to the rise in air pollutant emissions driven by economic and industrial expansion. To gain a deeper understanding of air pollution, a study was conducted during winter 2022-2023, assessing physical, chemical, and biological factors in Islamabad. The findings revealed that the average concentration of fine particulate matter (PM2.5) was notably greater than the World Health Organization (WHO) guidelines, reaching 133.39 µg/m³. Additionally, the average concentration of bacteria (308.64 CFU/m³) was notably greater than that of fungi (203.55 CFU/m³) throughout the study. Analytical analyses, including SEM-EDS and FTIR, showed that the PM2.5 in Islamabad is composed of various particles such as soot aggregates, coal fly ash, minerals, bio-particles, and some unidentified particles. EF analysis distinguished PM2.5 sources, enhancing understanding of pollutants origin, whereas Spearman's correlation analysis elucidated constituent interactions, further explaining air quality impact. The results from the Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-OES) indicated a gradual increase in the total elemental composition of PM2.5 from autumn to winter, maintaining high levels throughout the winter season. Furthermore, a significant variation was found in the mass concentration of PM2.5 when comparing samples collected in the morning and evening. The study also identified the presence of semi-volatile organic compounds (SVOCs) in PM2.5 samples, including polycyclic aromatic hydrocarbons (PAHs) and phenolic compounds, with notable variations in their concentrations. Utilizing health risk assessment models developed by the US EPA, we estimated the potential health risks associated with PM2.5 exposure, highlighting the urgency of addressing air quality issues. These findings provide valuable insights into the sources and composition of PM2.5 in Islamabad, contributing to a comprehensive understanding of air quality and its potential environmental and health implications.


Assuntos
Poluentes Atmosféricos , Material Particulado , Material Particulado/análise , Paquistão , Poluentes Atmosféricos/análise , Humanos , Monitoramento Ambiental , Cidades , Tamanho da Partícula , Poluição do Ar/análise
5.
Am J Primatol ; 86(2): e23580, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38012960

RESUMO

Stone tool use is a rare behavior across nonhuman primates. Here we report the first population of common long-tailed macaques (Macaca fascicularis fascicularis) who customarily used stone tools to open rock oysters (Saccostrea forskali) on a small island along the Thai Gulf in Koh Ped (KPE), eastern Thailand. We observed this population several times during the past 10 years, but no stone-tool use behavior was observed until our survey during the coronavirus disease 2019 (COVID-19) pandemic in July 2022. KPE is located in Pattaya City, a hotspot for tourism in Thailand. Tourists in this area frequently provided large amounts of food for the monkeys on KPE. During the COVID-19 curfew, however, tourists were not allowed to access the island, and monkeys began to face food scarcity. During this time, we observed stone-tool use behavior for the first time on KPE. Based on our observations, the first tool manipulation was similar to stone throwing (a known precursor of stone tool use). From our observations in March 2023, we found 17 subadult/adult animals performing the behavior, 15 of 17 were males and mostly solitary while performing the behavior. The M. f. fascicularis subspecies was confirmed by distribution, morphological characteristics, and mtDNA and SRY gene sequences. Taken together, we proposed that the stone tool use behavior in the KPE common long-tailed macaques emerged due to the COVID-19 food scarcity. Since traveling is no longer restricted many tourists have started coming back to the island, and there is a high risk for this stone tool-use behavior to disappear within this population of long-tailed macaques.


Assuntos
COVID-19 , Comportamento de Utilização de Ferramentas , Masculino , Animais , Feminino , Macaca fascicularis , Tailândia/epidemiologia , COVID-19/epidemiologia , Alimentos
6.
J Sci Food Agric ; 104(10): 6100-6107, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38445779

RESUMO

BACKGROUND: Dietary selenium (Se) deficiency, stemming from low Se concentrations in agricultural products, threatens human health. While Se-containing fertilizers can enhance the Se content in crops, the key factors governing Se biofortification with Se fertilization remain unclear. RESULTS: This study constructed a global meta-analysis dataset based on field experiments comprising 364 entries on Se content in agricultural products and 271 entries on their yield. Random forest models and mixed effects meta-analyses revealed that plant types (i.e., cereals, vegetables, legumes, and forages) primarily influenced Se biofortification, with Se fertilization rates being the next significant factor. The random forest model, which included variables like plant types, Se fertilization rates, methods and types of Se application, initial soil conditions (including Se content, organic carbon content, and pH), soil types, mean annual precipitation, and temperature, explained 82.14% of the variation in Se content and 48.42% of the yield variation in agricultural products. For the same agricultural products, the increase in Se content decreased with higher rates of Se fertilization. The increase in Se content in their edible parts will be negligible for cereals, forages, legumes, and vegetable crops, when Se fertilization rates were 164, 103, 144, and 147 g Se ha-1, respectively. Conversely, while low Se fertilization rates enhanced yields, high rates led to a yield reduction, particularly in cereals. CONCLUSION: Our findings highlight the need for balanced and precise Se fertilization strategies to optimize Se biofortification benefits and minimize the risk of yield reduction. © 2024 Society of Chemical Industry.


Assuntos
Biofortificação , Produtos Agrícolas , Fertilizantes , Selênio , Solo , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Grão Comestível/química , Grão Comestível/metabolismo , Fabaceae/química , Fabaceae/metabolismo , Fabaceae/crescimento & desenvolvimento , Fertilizantes/análise , Selênio/análise , Selênio/metabolismo , Solo/química , Verduras/química , Verduras/metabolismo , Verduras/crescimento & desenvolvimento
7.
Arch Microbiol ; 205(5): 170, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37017767

RESUMO

Balamuthia mandrillaris and Naegleria fowleri are protist pathogens that can cause fatal infections. Despite mortality rate of > 90%, there is no effective therapy. Treatment remains problematic involving repurposed drugs, e.g., azoles, amphotericin B and miltefosine but requires early diagnosis. In addition to drug discovery, modifying existing drugs using nanotechnology offers promise in the development of therapeutic interventions against these parasitic infections. Herein, various drugs conjugated with nanoparticles were developed and evaluated for their antiprotozoal activities. Characterizations of the drugs' formulations were accomplished utilizing Fourier-transform infrared spectroscopy, efficiency of drug entrapment, polydispersity index, zeta potential, size, and surface morphology. The nanoconjugates were tested against human cells to determine their toxicity in vitro. The majority of drug nanoconjugates exhibited amoebicidal effects against B. mandrillaris and N. fowleri. Amphotericin B-, Sulfamethoxazole-, Metronidazole-based nanoconjugates are of interest since they exhibited significant amoebicidal effects against both parasites (p < 0.05). Furthermore, Sulfamethoxazole and Naproxen significantly diminished host cell death caused by B. mandrillaris by up to 70% (p < 0.05), while Amphotericin B-, Sulfamethoxazole-, Metronidazole-based drug nanoconjugates showed the highest reduction in host cell death caused by N. fowleri by up to 80%. When tested alone, all of the drug nanoconjugates tested in this study showed limited toxic effects against human cells in vitro (less than 20%). Although these are promising findings, prospective work is warranted to comprehend the mechanistic details of nanoconjugates versus amoebae as well as their in vivo testing, to develop antimicrobials against the devastating infections caused by these parasites.


Assuntos
Amebíase , Amebicidas , Balamuthia mandrillaris , Naegleria fowleri , Humanos , Anfotericina B/farmacologia , Metronidazol/farmacologia , Metronidazol/uso terapêutico , Nanoconjugados/química , Nanoconjugados/uso terapêutico , Estudos Prospectivos , Amebicidas/química , Amebicidas/farmacologia , Sulfametoxazol/farmacologia , Sulfametoxazol/uso terapêutico , Amebíase/tratamento farmacológico , Amebíase/parasitologia
8.
J Appl Microbiol ; 134(4)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37024269

RESUMO

AIM: Herein, the anti-parasitic activity of azoles (fluconazole and itraconazole) and 5-nitroimdazole (metronidazole) against the brain-eating amoebae: Naegleria fowleri and Balamuthia mandrillaris was elucidated. METHODS AND RESULTS: Azoles and 5-nitroimidazole based nanoformulations were synthesized and characterized using a UV-visible spectrophotometer, atomic force microscopy, and fourier transform infrared spectroscopy. H1-NMR, EI-MS, and ESI-MS were performed to determine their molecular mass and elucidate their structures. Their size, zeta potential, size distribution, and polydispersity index (PDI) were assessed. Amoebicidal assays revealed that all the drugs and their nanoformulations, (except itraconazole) presented significant anti-amoebic effects against B. mandrillaris, while all the treatments indicated notable amoebicidal properties against N. fowleri. Amoebicidal effects were radically enhanced upon conjugating the drugs with nanoparticles. The IC50 values for KM-38-AgNPs-F, KM-20-AgNPs-M, and KM-IF were 65.09, 91.27, and 72.19 µg.mL-1, respectively, against B. mandrillaris. Whereas against N. fowleri, the IC50 values were: 71.85, 73.95, and 63.01 µg.mL-1, respectively. Additionally, nanoformulations significantly reduced N. fowleri-mediated host cell death, while nanoformulations along with fluconazole and metronidazole considerably reduced Balamuthia-mediated human cell damage. Finally, all the tested drugs and their nanoformulations revealed limited cytotoxic activity against human cerebral microvascular endothelial cell (HBEC-5i) cells. CONCLUSION: These compounds should be developed into novel chemotherapeutic options for use against these distressing infections due to free-living amoebae, as currently there are no effective treatments.


Assuntos
Amebicidas , Amoeba , Antiprotozoários , Naegleria fowleri , Humanos , Azóis/farmacologia , Fluconazol/farmacologia , Metronidazol/farmacologia , Itraconazol/farmacologia , Antiprotozoários/farmacologia , Amebicidas/farmacologia , Amebicidas/química , Encéfalo
9.
Exp Parasitol ; 246: 108474, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36708943

RESUMO

Acanthamoeba castellanii causes granulomatous amoebic encephalitis, an uncommon but severe brain infection and sight-threatening Acanthamoeba keratitis. Most of the currently used anti-amoebic treatments are not always effective, due to persistence of the cyst stage, and recurrence can occur. Here in this study we synthesize cinnamic acid and lactobionic acid-based magnetic nanoparticles (MNPs) using co-precipitation technique. These nanoformulations were characterized by Fourier transform infrared spectroscopy and Atomic form microscopy. The drugs alone (Hesperidin, Curcumin and Amphotericin B), magnetic NPs alone, and drug-loaded nano-formulations were evaluated at a concentration of 100 µg/mL for antiamoebic activity against a clinical isolate of A. castellanii. Amoebicidal assays revealed that drugs and conjugation of drugs and NPs further enhanced amoebicidal effects of drug-loaded nanoformulations. Drugs and drug-loaded nanoformulations inhibited both encystation and excystation of amoebae. In addition, drugs and drug-loaded nanoformulations inhibited parasite binding capability to the host cells. Neither drugs nor drug-loaded nanoformulations showed cytotoxic effects against host cells and considerably reduced parasite-mediated host cell death. Overall, these findings imply that conjugation of medically approved drugs with MNPs produce potent anti-Acanthamoebic effects, which could eventually lead to the development of therapeutic medications.


Assuntos
Acanthamoeba castellanii , Amebíase , Amebicidas , Nanopartículas Metálicas , Humanos , Nanopartículas Metálicas/química , Amebíase/parasitologia , Amebicidas/química
10.
BMC Public Health ; 23(1): 1487, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542311

RESUMO

BACKGROUND: In Sub-Saharan Africa, the nutritional status of children born to teenage mothers deserves critical attention. Maternal knowledge and attitudes concerning infant and young child feeding (IYCF) may predict actual practices and child nutritional status. This study created and validated the Teen Moms Child Feeding Questionnaire for Sub-Saharan Africa. METHODS: A literature search on IYCF knowledge and attitude gaps in teenage mothers generated scale items. Ten nutrition experts and six teenage mothers assessed content validity and comprehensibility, respectively. Construct validation was conducted by item response theory (IRT) and confirmatory factor analysis (CFA), in 150 teenage mothers in rural communities of Abuja, Nigeria. Model fit parameters were estimated by standardized chi-square tests. Internal consistency reliability was determined by marginal reliability and Cronbach's alpha. In a sub-sample of 40 women who completed the questionnaire two weeks later, test-retest reliability was assessed via intraclass correlations. RESULTS: The IRT analysis retained 23 knowledge items on infant food type, breastfeeding and complementary feeding, with acceptable discrimination and difficulty. CFA produced a six-factor solution (exclusive breastfeeding, breast milk expression, meal frequency, responsive feeding, dietary diversity, and barriers) with 17 attitude items. Confirmatory fit and Tucker Lewis indices > 0.9; Root Mean Square Errors of Approximation and Standardized Root Mean Square Residuals < 0.08, showed good model fit. Overall Cronbach's alpha of the attitude scale (0.843), subscales (≥ 0.6) and high intraclass correlation coefficients (> 0.75) indicated reliability. CONCLUSION: The Teen Moms Child Feeding Questionnaire for Sub-Saharan Africa is a valid assessment tool for IYCF knowledge and attitudes of teenage mothers.


Assuntos
Aleitamento Materno , Fenômenos Fisiológicos da Nutrição do Lactente , Lactente , Humanos , Feminino , Criança , Adolescente , Reprodutibilidade dos Testes , Inquéritos e Questionários , África Subsaariana
11.
J Pak Med Assoc ; 73(10): 2073-2076, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37876074

RESUMO

To assess the effects of excessive screen time on the health of medical and dental students due to online teaching during the COVID-19 pandemic. It was a descriptive cross-sectional study, conducted in Bahria University of Health Sciences from June 2022 to September 2022 after getting ethical approval. A total of 200 students who attended online teaching modules for at least one year through online teaching Apps, were included. A structured questionnaire was distributed using google forms. The results revealed that factors including strain on the eyes, restlessness, declined academic performance and exercise during lockdown, along with feeling connected as a group had a significant association with increased screen time. Excessive screen time has various adverse effects on the physical and mental health of medical and dental students. For improving students' physical and mental health during online teaching we need to change teaching strategies and support the introduction of flipped classroom.


Assuntos
Saúde Mental , Estudantes de Medicina , Humanos , Estudos Transversais , Pandemias , Tempo de Tela , Estudantes de Odontologia
12.
Pak J Med Sci ; 39(6): 1647-1651, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37936786

RESUMO

Objective: To investigate the Bioequivalence of Anplag® 90mg (Ticagrelor) tablet and Brilinta® 90 mg (Ticagrelor) tablet under fasting conditions in healthy Pakistani subjects. Method: This was an open-label, cross-over, randomized, single-dose, two-period, single-center Bioequivalence Study conducted at Center of Bioequivalence Studies and Clinical Research (CBSCR), ICCBS, University of Karachi, Karachi, Pakistan from September 2020 to January 2021. This was an open-label, randomized, single-dose, two-period, cross-over Bioequivalence Study. After randomization, a single dose of Ticagrelor 90mg tablet (test or reference drug) were administered orally in 1:1 ratio to each subject under fasting conditions. Seven days washout period was kept between the two periods in order to avoid carry over. Blood samples were then taken up to 48th hours post-dose. Point estimates and 90% confidence intervals (CI) for the ratio of the log-transformed values were calculated. Bioequivalence assessment of both, the reference and the test drugs were based on the primary Pharmacokinetic PK metrics including peak maximum concentration (Cmax), area under the curve (AUC) from zero to last quantifiable concentration (AUClast), and AUC from zero to infinity (AUCtotal) after log-transformation of data with ANOVA. In this bioequivalence study, the primary pharmacokinetic parameters were assessed for both Ticagrelor and its Active Metabolite (AR-C124910XX). Safety endpoints were evaluated by monitoring adverse events (AEs). Results: The 90% Confidence Intervals (CIs) of the Geometric Mean Ratio for primary PK parameters including Cmax, AUClast, and AUCtotal all were within the accepted bioequivalence range of 80%- 125%. In the current study, no serious adverse events were reported. Conclusion: Our results showed that the two tested formulations of Ticagrelor tablets were bioequivalent and well tolerated.Trial Registration: ClinicalTrials.gov Identifier: NCT04941196.

13.
J Biol Inorg Chem ; 27(4-5): 471-483, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35821138

RESUMO

A sensitive scheme was established for the detection of vitamin C (Ascorbic acid) and vitamin B1 (Thiamin HCl) using Maltol capped AgNPs (McAgNPs) as colorimetric sensor. The designed scheme showed an instant alteration in color from yellow to orange and green for vitamin-C and vitamin B1 sequentially. The probe was sensitive in a concentration range of (0-1 µM) with limit of detection 0.064 and 0.038 µM for vitamin C and vitamin B1 sequentially. The interaction mechanism between vitamin C and vitamin B1 and McAgNPs was evaluated by visible spectroscopy, FTIR, and AFM. Vitamin C attaches on the surface of nanoparticles by C=O group, while OH, C-S-C, and NH2 groups are involved in the binding of vitamin B1 with McAgNPs. The Vit-C/Vit-B1-McAgNPs complexes were stable over a wide range of pHs. The size of McAgNPs increased after the interaction of vitamin C/vitamin B1 from 30-40 nm to 500 and 400 nm sequentially. The scheme was successfully applied for the detection of vitamin C and vitamin B1 in urine, plasma, water, and commercial pharmaceutical tablets with good recoveries. The scheme was ascertained to be more sensitive than many other formerly described schemes.


Assuntos
Colorimetria , Nanopartículas Metálicas , Ácido Ascórbico , Colorimetria/métodos , Aromatizantes , Nanopartículas Metálicas/química , Prata/química , Tiamina , Vitaminas
14.
Environ Res ; 212(Pt A): 113138, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35364043

RESUMO

Recent trends in adsorption of Chromium (Cr), Copper (Cu), Lead (Pb) and Mercury (Hg) in wastewater using (i) carbonaceous materials including activated carbon (AC) and biochar (BC), and (ii) nanomaterials including nano zero-valent iron (nZVI) and MXenes have been discussed in this paper. It has been found that adsorption capacity depends largely on the adsorbent modification technique, initial pH of wastewater, dosage of adsorbent, contact time and initial concentration of the pollutants. The pH value ranges for maximum removal of Cr, Cu, Pb and Hg have been reported as 2-4, 5-6, 5-8 and 3-8, respectively. Up to 99% removal of metals has been reported using AC, BC, nZVI and MXene. The mechanism involves the reduction and chemical adsorption of metals. AC and BC have a higher surface area (up to 5000 m2/g) compared to nZVI (up to 500 m2/g) and MXene (up to 67.66 m2/g). However, the higher reactivity and regeneration capacity of nZVI and MXene make them suitable adsorbents. From a practical point of view the application of adsorbents for real effluents, cost analysis, regeneration capability and reuse of heavy metals are some aspects that need attention in future studies. The removal efficiencies of AC and BC are comparable to the nZVI and MXene. The cost analysis may be an attractive aspect to decide the future application of these adsorbents at large scale.


Assuntos
Mercúrio , Nanoestruturas , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Cromo/análise , Cobre/análise , Íons/análise , Ferro/análise , Chumbo/análise , Mercúrio/análise , Águas Residuárias/análise , Água/análise , Poluentes Químicos da Água/análise
15.
BMC Vet Res ; 18(1): 375, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261856

RESUMO

BACKGROUND: This study aimed to evaluate the ameliorative effects of dietary supplementation of local bentonite clay (BN) and distillery sludge (DS) alone and in combination on ochratoxin-A (OTA) induced toxicity in broilers. For this purpose, day-old-broiler chicks (n = 270) were procured from the local market and reared under standard management conditions. After 7 days of acclimatization, birds were divided into 2 main groups A and B with respect to OTA inclusion level in feed, each with four sub-groups viz. A1-A4, each challenged with OTA at a dietary inclusion level of 250 µg/kg feed and B1-B4, each challenged with OTA at the level of 500 µg/kg feed and a common control group that was fed with basal feed throughout the experiment. In groups A and B, BN and DS were administered with feed at the rate of 10 g/kg of feed and 5 g/kg of feed alone and in combination, respectively. RESULTS: Results showed that OTA administration alone resulted in poor feed conversion ratio (FCR) and immunological responses along with increased serum levels of alanine transaminase (ALT), Aspartate transaminase (AST), urea and creatinine (P < 0.05). A significant decrease (P < 0.05) in serum protein levels (albumin, globulin and total protein) was also observed in OTA-fed groups in a dose-dependent manner. The addition of BN at 10 g/kg of OTA-contaminated feed resulted in better FCR and immunological responses as compared to those fed OTA only. The BN supplementation also conferred protection against elevation of serum biochemical parameters when compared with OTA-fed groups. However, the addition of DS could not provide significant protection (P > 0.05) on alteration of serum biochemical parameters in response to the OTA induced toxicity. The combined supplementation of BN and DS resulted in amelioration of OTA-induced toxicity and showed improved FCR, immunological, hematological and serum biochemical parameters (P < 0.05) when compared with other groups. Similarly, BN and DS resulted in a significant decline (P < 0.05) in the OTA tissue residues compared with other groups and control. CONCLUSION: In conclusion, combined dietary supplementation of BN (10 mg/kg) and DS (05 mg/kg) in feed reduced the toxic effects of OTA contamination at levels of 250 and 500 µg/kg of feed in broilers. So, the combination products of BN and DS may be successfully developed for use in poultry for protection against OTA-induced toxicity in broilers.


Assuntos
Ocratoxinas , Animais , Ocratoxinas/toxicidade , Ocratoxinas/química , Galinhas , Bentonita , Argila , Esgotos , Ração Animal/análise , Alanina Transaminase , Creatinina , Dieta/veterinária , Suplementos Nutricionais , Aspartato Aminotransferases , Ureia , Albuminas
16.
Molecules ; 27(19)2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36235305

RESUMO

Hydrazones are active compounds having an azomethine -NHN=CH group and are widely studied owing to their ease of preparation and diverse pharmacological benefits. Novel isonicotinic hydrazone derivatives of vanillin aldehyde and salicyl aldehyde were synthesized that had azomethine linkages and were characterized by UV-Visible, FTIR, EI-MS, 1H-NMR and 13C-NMR spectroscopy. The compounds were screened for their antibacterial activity against Staphylococcus aureus, Bacillus subtilus, and Escherichia coli using disc diffusion and minimum inhibitory concentration (MIC) methods. For cytotoxicity, a brine shrimp lethality test was performed to calculate the lethal concentration (LC50). The results demonstrated appreciable antibacterial activities against the applied strains, amongst which the compounds coded NH3 and NH5 showed maximum inhibition and MIC responses. In terms of cytotoxic activity, the maximum effect was observed in compound NH5 and NH6 treatments with minimum survival percentages of 36.10 ± 3.45 and 32.44 ± 2.0, respectively. These hydrazones could be potential candidates in antitumorigenic therapy against various human cancer cells.


Assuntos
Antineoplásicos , Hidrazonas , Aldeídos/farmacologia , Antibacterianos/química , Antineoplásicos/farmacologia , Compostos Azo , Escherichia coli , Humanos , Hidrazonas/química , Testes de Sensibilidade Microbiana , Tiossemicarbazonas
17.
BMC Microbiol ; 21(1): 51, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33596837

RESUMO

BACKGROUNDS: Escherichia coli K1 causes neonatal meningitis. Transcriptome studies are indispensable to comprehend the pathology and biology of these bacteria. Recently, we showed that nanoparticles loaded with Hesperidin are potential novel antibacterial agents against E. coli K1. Here, bacteria were treated with and without Hesperidin conjugated with silver nanoparticles, and silver alone, and 50% minimum inhibitory concentration was determined. Differential gene expression analysis using RNA-seq, was performed using Degust software and a set of genes involved in cell stress response and metabolism were selected for the study. RESULTS: 50% minimum inhibitory concentration with silver-conjugated Hesperidin was achieved with 0.5 µg/ml of Hesperidin conjugated with silver nanoparticles at 1 h. Differential genetic analysis revealed the expression of 122 genes (≥ 2-log FC, P< 0.01) in both E. coli K1 treated with Hesperidin conjugated silver nanoparticles and E. coli K1 treated with silver alone, compared to untreated E. coli K1. Of note, the expression levels of cation efflux genes (cusA and copA) and translocation of ions, across the membrane genes (rsxB) were found to increase 2.6, 3.1, and 3.3- log FC, respectively. Significant regulation was observed for metabolic genes and several genes involved in the coordination of flagella. CONCLUSIONS: The antibacterial mechanism of nanoparticles maybe due to disruption of the cell membrane, oxidative stress, and metabolism in E. coli K1. Further studies will lead to a better understanding of the genetic mechanisms underlying treatment with nanoparticles and identification of much needed novel antimicrobial drug candidates.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Perfilação da Expressão Gênica , Hesperidina/farmacologia , Nanopartículas Metálicas/química , Prata/farmacologia , Hesperidina/química , Testes de Sensibilidade Microbiana , Estresse Oxidativo/efeitos dos fármacos , Transcriptoma
18.
Environ Res ; 196: 110427, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33221307

RESUMO

Interior settled dust is one of the greatest threats of potentially toxic metal(oid)s (PTMs) exposure to the children, especially in the school environment. Therefore, it is more worthy of having in-depth knowledge of compositional characteristics of school dust. Forty schools were selected of Lahore city for dust sampling. The school dust was analyzed to determine the PTMs (As, Cd, Cr, Cu, Ge, Mo, Ni, Pb, Sb, Sn, Sr, V, and Zn) concentrations using ICP-MS. The morphological characteristics, PTMs speciation, and mineralogy of school dust were examined using SEM with EDS, XPS, and XRD, respectively. Moreover, the geo-accumulation index (Igeo), potential ecological risk index (PERI), and multivariate statistical analysis were employed to assess the pollution levels, ecological risk, and source identification of PTMs, respectively. The Igeo indicated a heavily-extreme pollution level of Cd (Igeo = 4.92), moderate-heavy pollution of Zn (Igeo = 3.22), and Pb (Igeo = 2.78), and slight-moderate pollution of Cr (Igeo = 1.62), and Cu (Igeo = 1.53). The ecological risk has been found extremely high for Cd and moderately high for Pb and As, while potential ecological risk found extremely high posed by cumulatively all selected PTMs. Multivariate statistical analysis showed that sources of PTMs comprise of natural processes as well as several anthropogenic processes like vehicular emissions, agricultural and industrial activities. The SEM, XRD, and XPS analyses demonstrated the presence of airborne particles and PTMs containing minerals with several toxic chemical species in school dust. This study can help to develop strategies to reduce school indoor pollution and hence to establish an eco-friendly learning environment for children.


Assuntos
Poeira , Metais Pesados , Criança , China , Cidades , Poeira/análise , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Paquistão , Medição de Risco , Instituições Acadêmicas
19.
Biotechnol Appl Biochem ; 68(5): 992-1002, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32885506

RESUMO

This study reports the green synthesis and urease inhibitory activities of Ag and Au nanoparticles (NPs) using Crataegus oxyacantha extract. The synthesized NPs were characterized by UV-visible, FT-IR spectroscopy, atomic force microscopy, and scanning electron microscopy. The obtained NPs were spherical in shape, and their size was around 85 nm. A strong correlation between the phytochemicals present in the extract and their capability for the synthesis of NPs was observed. Furthermore, the shape, size, stability, and bioactivity of the NPs were strongly influenced by the stabilizing phytochemicals. The experimental analysis suggested that these NPs have substantial stability in a diverse range of physiological conditions such as pH, salinity, and temperature. The NPs exhibited potent urease enzyme inhibitory activities with percent inhibition of 99.25 and IC50 value of 1.38 ± 0.3, comparable to the standard (thiourea percent inhibition, that is, 98.2% and IC50 value 5.3 ± 0.04). These results suggested that the proposed NPs could be used in the homeopathic and pharmaceutical industries for biomedical applications.


Assuntos
Crataegus/química , Inibidores Enzimáticos/farmacologia , Química Verde , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Urease/antagonistas & inibidores , Canavalia/enzimologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Ouro/química , Ouro/farmacologia , Nanopartículas Metálicas/química , Tamanho da Partícula , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Prata/química , Prata/farmacologia , Urease/metabolismo
20.
Sensors (Basel) ; 21(21)2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34770608

RESUMO

Highly stable, small-sized and evenly distributed solid mercury nanoparticles capped with ibuprofen (Ibu-HgNPs) were prepared via reduction with hydrazine and capped with ibuprofen as a stabilizing agent. Characterization of Ibu-HgNPs was carried out by UV-Vis spectrophotometry and transmission electron microscopy (TEM). The prepared Ibu-HgNPs were immobilized onto a glassy carbon electrode (GCE) and used for the first time as the sensing element for voltammetric determination of low concentrations of acrylamide (AA) in aqueous solutions. Various parameters such as the type of supporting electrolyte, voltammetric mode, frequency, deposition time, stirring rate and initial potential were optimized to obtain the highest peak current of AA. The sensor delivered the best results in combination with the square wave voltammetry (SWV) mode, with good repeatability (relative standard deviation (RSD) of 25 repetitions was 1.4% for 1000 ppb AA). The study further revealed that Ibu-HgNPs are strongly adhered to GCE and hence do not contaminate the environment even after several runs. The newly developed AA sensor provides linear calibration dependence in the range of 100-1300 ppb with an R2 value of 0.996 and limit of detection (LOD) of 8.5 ppb. Negligible interference was confirmed from several organic compounds, cations and anions. The developed sensor was successfully applied for AA determination in various types of environmental real water samples to prove its practical usefulness and applicability.


Assuntos
Mercúrio , Nanopartículas , Acrilamida , Técnicas Eletroquímicas , Eletrodos , Ibuprofeno
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