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1.
Biol Trace Elem Res ; 201(9): 4558-4566, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36477658

RESUMO

Toxic metals (TMs) are serious health hazard and are known to accumulate in fruits, which are consumed by people, owning to their distinct sweet flavor and potential health benefits. In the present study, arsenic (As), lead (Pb), chromium (Cr), copper (Cu), cadmium (Cd), nickel (Ni), and mercury (Hg) were measured by atomic absorption spectrometry (AAS) techniques in orange samples from 11 farmhouses of Sargodha, Pakistan. Principal component analysis (PCA) is a very useful analysis and data-reducing tool. This technique was used to explore the relationship between different metal levels in the oranges. The conventional wet acid digestion method was validated and assured with two (02) certified reference materials NIST-SRM 1515-Apple and (CRM) NIST-1570a Spinach Leaves by recovery test coupled with standard addition procedure. The results showed that Cd and Cr average daily intakes are 0.084 and 0.15 mg slightly higher than World Health Organization/Food and Agriculture Organization of the United Nations (WHO/FAO) recommended tolerable daily intake respectively. The assessment of health risk was also carried out in form of total hazard quotient (THQ) and hazard index (HI), indicating three heavy metals (Pb, Cd, and Cr) have significant human health risk potential to consumers while Cu, As, Hg, and Ni have non-significant (THQ < 1) health risks.


Assuntos
Arsênio , Citrus sinensis , Citrus , Mercúrio , Metais Pesados , Humanos , Cádmio/análise , Paquistão , Chumbo/análise , Metais Pesados/análise , Níquel/análise , Cromo/análise , Mercúrio/análise , Arsênio/análise , Medição de Risco , Monitoramento Ambiental
2.
Molecules ; 27(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36235187

RESUMO

Ionic liquids (ILs) have emerged as active pharmaceutical ingredients because of their excellent antibacterial and biological activities. Herein, we used the green-chemistry-synthesis procedure, also known as the metathesis method, to develop three series of ionic liquids using 1-methyl-3-butyl imidazolium, butyl pyridinium, and diethyldibutylammonium as cations, and bromide (Br-), methanesulfonate (CH3SO3-), bis(trifluoromethanesulfonyl)imide (NTf2-), dichloroacetate (CHCl2CO2-), tetrafluoroborate (BF4-), and hydrogen sulfate (HSO4-) as anions. Spectroscopic methods were used to validate the structures of the lab-synthesized ILs. We performed an agar well diffusion assay by using pathogenic bacteria that cause various infections (Escherichia coli; Enterobacter aerogenes; Klebsiella pneumoniae; Proteus vulgaris; Pseudomonas aeruginosa; Streptococcus pneumoniae; Streptococcus pyogenes) to scrutinize the in vitro antibacterial activity of the ILs. It was established that the nature and unique combination of the cations and anions were responsible for the antibacterial activity of the ILs. Among the tested ionic liquids, the imidazolium cation and NTf2- and HSO4- anions exhibited the highest antibacterial activity. The antibacterial potential was further investigated by in silico studies, and it was observed that bis(trifluoromethanesulfonyl)imide (NTf2-) containing imidazolium and pyridinium ionic liquids showed the maximum inhibition against the targeted bacterial strains and could be utilized in antibiotics. These antibacterial activities float the ILs as a promising alternative to the existing antibiotics and antiseptics.


Assuntos
Compostos de Amônio , Anti-Infecciosos Locais , Líquidos Iônicos , Ágar , Ânions/química , Antibacterianos/farmacologia , Brometos/química , Dióxido de Carbono , Cátions/química , Escherichia coli , Hidrocarbonetos Fluorados , Hidrogênio , Imidazóis/química , Imidazóis/farmacologia , Imidas , Líquidos Iônicos/química , Líquidos Iônicos/farmacologia , Mesilatos , Preparações Farmacêuticas , Sulfatos
3.
Polymers (Basel) ; 13(22)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34833163

RESUMO

A poly(l-lactic acid)/nanohydroxyapatite (PLLA/nHA) scaffold works as a bioactive, osteoconductive scaffold for bone-tissue engineering, but its low degradation rate limits embedded HA in PLLA to efficiently interact with body fluids. In this work, nano-hydroxyapatite (nHA) was added in lower filler loadings (1, 5, 10, and 20 wt%) in a poly(l-lactic acid)/cyclo olefin copolymer10 wt% (PLLA/COC10) blend to obtain novel poly(l-lactic acid)/cyclo olefin copolymer/nanohydroxyapatite (PLLA/COC10-nHA) scaffolds for bone-tissue regeneration and repair. Furthermore, the structure-activity relationship of PLLA/COC10-nHA (ternary system) nanocomposites in comparison with PLLA/nHA (binary system) nanocomposites was systematically studied. Nanocomposites were evaluated for structural (morphology, crystallization), thermomechanical properties, antibacterial potential, and cytocompatibility for bone-tissue engineering applications. Scanning electron microscope images revealed that PLLA/COC10-nHA had uniform morphology and dispersion of nanoparticles up to 10% of HA, and the overall nHA dispersion in matrix was better in PLLA/COC10-nHA as compared to PLLA/nHA. Fourier transformation infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), and differential scanning calorimetry (DSC) studies confirmed miscibility and transformation of the α-crystal form of PLLA to the ά-crystal form by the addition of nHA in all nanocomposites. The degree of crystallinity (%) in the case of PLLA/COC10-nHA 10 wt% was 114% higher than pure PLLA/COC10 and 128% higher than pristine PLLA, indicating COC and nHA are acting as nucleating agents in the PLLA/COC10-nHA nanocomposites, causing an increase in the degree of crystallinity (%). Moreover, PLLA/COC10-nHA exhibited 140 to 240% (1-20 wt% HA) enhanced mechanical properties in terms of ductility as compared to PLLA/nHA. Antibacterial activity results showed that 10 wt% HA in PLLA/COC10-nHA showed substantial activity against P. aeruginosa, S. aureus, and L. monocytogenes. In vitro cytocompatibility of PLLA/COC10 and PLLA nanocomposites with nHA osteoprogenitor cells (MC3T3-E1) and bone mesenchymal stem cells (BMSC) was evaluated. Both cell lines showed two- to three-fold enhancement in cell viability and 10- to 30-fold in proliferation upon culture on PLLA/COC10-nHA as compared to PLLA/nHA composites. It was observed that the ternary system PLLA/COC10-nHA had good dispersion and interfacial interaction resulting in improved thermomechanical and enhanced osteoconductive properties as compared to PLLA/nHA.

4.
Int J Biol Macromol ; 185: 419-433, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34166695

RESUMO

Hydrogels were prepared by mixing protein and carbohydrate-based biopolymers to increase the mechanical properties and efficient cell adhesion and proliferation for wound healing applications. Microcrystalline cellulose (MCC) and its 6-deoxy-aminocellulose derivatives (6-deoxy-6-hydrazide Cellulose (Cell-Hyd), 6-deoxy-6-diethylamide Cellulose (Cell-DEA), and 6-deoxy-6-diethyltriamide Cellulose (Cell-DETA)) were embedded in methacrylated gelatin (GelMA). GelMA and 6-deoxy-aminocellulose derivatives were synthesized and characterized by spectroscopic techniques. MCC and cellulose derivatives embedded GelMA gels were characterized by FTIR, SEM and Tensile mechanical testing. SEM images revealed that, porosity of the amine MCC incorporated GelMA was decreased compared to GelMA and MCC incorporated GelMA. Tensile strain of GelMA 61.30% at break was increased to 64.3% in case of GelMA/Cell-HYD. In vitro cytocompatibility and cell proliferation using NIH-3T3 cell lines showed cell density trend on scaffold as GelMA/Cell-DETA>GelMA/Cell-Hyd > GelMA. Scratch assay for wound healing revealed that GelMA/Cell-DETA showed complete wound closure, while GelMA/Cell-Hyd and GelMA exhibited 85.7%, and 66.1% wound healing, respectively in 8 h. In vivo tests on rats revealed that GelMA/Cell-DETA exhibited 98% wound closure on day 9, whereas GelMA/Cell-Hyd exhibited 97.7% and GelMA 66.1% wound healing on day 14. Our findings revealed that GelMA embedded amine MCC derivatives hydrogels can be applied for achieving accelerated wound healing.


Assuntos
Celulose/farmacologia , Gelatina/química , Metacrilatos/química , Cicatrização/efeitos dos fármacos , Animais , Proliferação de Células , Celulose/química , Modelos Animais de Doenças , Feminino , Hidrogéis/química , Camundongos , Células NIH 3T3 , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração , Alicerces Teciduais
5.
Polymers (Basel) ; 12(11)2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33182562

RESUMO

Cellulose based materials are emerging in the commercial fields and high-end applications, especially in biomedicines. Aminated cellulose derivatives have been extensively used for various applications but limited data are available regarding its cytotoxicity studies for biomedical application. The aim of this study is to synthesize different 6-deoxy-amino-cellulose derivatives from Microcrystalline cellulose (MCC) via tosylation and explore their cytotoxic potential against normal fibroblasts, melanoma and breast cancer. 6-deoxy-6-hydrazide Cellulose (Cell Hyd) 6-deoxy-6-diethylamide Cellulose (Cell DEA) and 6-deoxy-6-diethyltriamine Cellulose (Cell DETA) were prepared and characterized by various technologies like Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR), nuclear magnetic resonance spectroscopy (NMR), X-ray diffractogram (XRD), Scanning Electron microscopy (SEM), Elemental Analysis and Zeta potential measurements. Cytotoxicity was evaluated against normal fibroblasts (NIH3T3), mouse skin melanoma (B16F10), human epithelial adenocarcinoma (MDA-MB-231) and human breast adenocarcinoma (MCF-7) cell lines. IC50 values obtained from cytotoxicity assay and live/dead assay images analysis showed MCC was non cytotoxic while Cell Hyd, Cell DEA and Cell DETA exhibited noncytotoxic activity up to 200 µg/mL to normal fibroblast cells NIH3T3, suggesting its safe use in medical fields. The mouse skin melanoma (B16F10) are the most sensitive cells to the cytotoxic effects of Cell Hyd, Cell DEA and Cell DETA, followed by human breast adenocarcinoma (MCF-7). Based on our study, it is suggested that aminated cellulose derivatives could be promising candidates for tissue engineering applications and in cancer inhibiting studies in future.

6.
J Vasc Access ; 11(1): 26-30, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20119921

RESUMO

BACKGROUND AND OBJECTIVE: The rising prevalence of end-stage renal disease has added to the demands of renal replacement therapy in the form of hemodialysis (HD) in lieu of unmitigated needs of renal transplants. The best available angioaccess for HD is the autogenous arteriovenous fistula. Many techniques for arteriovenous anastomosis have been reported, but there is dearth of data which study the side-to-side arteriovenous anastomosis with concomitant ligation and division of the distal venous arm. This study aimed to describe the clinical outcome of the fistulae constructed with this particular technique. METHODS: It is a descriptive and retrospective review in which all patients who underwent the operation with this particular technique in a certain time period were included. The data entry and analysis was done using SPSS 15. Only descriptive statistics are used. Demographic details, primary patency, end point patency and fistula survival were calculated. RESULTS: There were 77 patients, 61 males and 16 females. Radiocephalic arteriovenous anastomosis was constructed in 65 patients, brachiocephalic in 11 patients and brachiobasilic in one patient. Primary patency was 96.1% and end point patency was 90.9% with a median survival of 44 weeks at the end point. CONCLUSION: This particular technique of fistula construction has excellent patency rates, fistula survival and lesser complications when compared to what has been reported for other methods. It is therefore recommended that the technique of angioaccess reported in this study may be considered as a first option.


Assuntos
Derivação Arteriovenosa Cirúrgica , Falência Renal Crônica/terapia , Diálise Renal , Extremidade Superior/irrigação sanguínea , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Artéria Braquial , Veias Braquiocefálicas/cirurgia , Criança , Feminino , Humanos , Ligadura , Masculino , Pessoa de Meia-Idade , Paquistão , Artéria Radial/cirurgia , Fluxo Sanguíneo Regional , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular , Adulto Jovem
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