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1.
Med Oncol ; 41(5): 112, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592510

RESUMO

Despite recent advancements in the diagnosis and treatment of breast cancer (BC), patient outcomes in terms of survival, recurrence, and disease progression remain suboptimal. A significant factor contributing to these challenges is the cellular heterogeneity within BC, particularly the presence of breast cancer stem cells (BCSCs). These cells are thought to serve as the clonogenic nexus for new tumor growth, owing to their hierarchical organization within the tumor. This descriptive review focuses on the evolving strategies to target BCSCs, which have become a pivotal aspect of therapeutic development. We explore a variety of approaches, including targeting specific tumor surface markers (CD133 and CD44), transporters, heat shock proteins, and critical signaling pathways like Notch, Akt, Hedgehog, KLF4, and Wnt/ß-catenin. Additionally, we discuss the modulation of the tumor microenvironment through the CXCR-12/CXCR4 axis, manipulation of pH levels, and targeting hypoxia-inducible factors, vascular endothelial growth factor, and CXCR1/2 receptors. Further, this review focuses on the roles of microRNA expression, strategies to induce apoptosis and differentiation in BCSCs, dietary interventions, dendritic cell vaccination, oncolytic viruses, nanotechnology, immunotherapy, and gene therapy. We particularly focused on studies reporting identification of BCSCs, their unique properties and the efficacy of various therapeutic modalities in targeting these cells. By dissecting these approaches, we aim to provide insights into the complex landscape of BC treatment and the potential pathways for improving patient outcomes through targeted BCSC therapies.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/terapia , Fator A de Crescimento do Endotélio Vascular , Mama , Imunoterapia , Apoptose , Biomarcadores Tumorais , Microambiente Tumoral
2.
J Infect Public Health ; 17(5): 906-917, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569270

RESUMO

BACKGROUND: With the global increase in antibacterial resistance, the challenge faced by developing countries is to utilize the available antibiotics, alone or in combination, against resistant bacterial strains. We aimed to encapsulate the levofloxacin (LVX) into polymeric nanoparticles using biodegradable polymers i.e. Chitosan and PLGA, estimating their physicochemical characteristics followed by functional assessment as nanocarriers of levofloxacin against the different resistant strains of bacteria isolated from biological samples collected from tertiary care hospital in Lahore, Pakistan. METHODS: LVX-NPs were synthesized using ion gelation and double emulsion solvent-evaporation method employing chitosan (CS) and poly-lactic-co-glycolic acid (PLGA), characterized via FTIR, XRD, SEM, and invitro drug release studies, while antibacterial activity was assessed using Kirby-Bauer disc-diffusion method. RESULTS: Data revealed that the levofloxacin-loaded chitosan nanoparticles showed entrapment efficiency of 57.14% ± 0.03 (CS-I), 77.30% ± 0.08(CS-II) and 87.47% ± 0.08 (CS-III). The drug content, particle size, and polydispersity index of CS-I were 52.22% ± 0.2, 559 nm ± 31 nm, and 0.030, respectively, whereas it was 66.86% ± 0.17, 595 nm ± 52.3 nm and 0.057, respectively for CS-II and 82.65% ± 0.36, 758 nm ± 24 nm and 0.1, respectively for CS-III. The PLGA-levofloxacin nanoparticles showed an entrapment efficiency of 42.80% ± 0.4 (PLGA I) and 23.80% ± 0.4 (PLGA II). The drug content, particle size and polydispersity index of PLGA-I were 86% ± 0.21, 92 nm ± 10 nm, and 0.058, respectively, whereas it was 52.41% ± 0.45, 313 nm ± 32 nm and 0.076, respectively for PLGA-II. The XRD patterns of both polymeric nanoparticles showed an amorphous nature. SEM analysis reflects the circular-shaped agglomerated nanoparticles with PLGA polymer and dense spherical nanoparticles with chitosan polymer. The in-vitro release profile of PLGA-I nanoparticles showed a sustained release of 82% in 120 h and it was 58.40% for CS-III. Both types of polymeric nanoparticles were found to be stable for up to 6 months without losing any major drug content. Among the selected formulations, CS-III and PLGA-I, CS-III had better antibacterial potency against gram+ve and gram-ve bacteria, except for K. pneumonia, yet, PLGA-I demonstrated efficacy against K. pneumonia as per CSLI guidelines. All formulations did not exhibit any signs of hemotoxicity, nonetheless, the CS-NPs tend to bind on the surface of RBCs. CONCLUSION: These data suggested that available antibiotics can effectively be utilized as nano-antibiotics against resistant bacterial strains, causing severe infections, for improved antibiotic sensitivity without compromising patient safety.


Assuntos
Quitosana , Glicolatos , Nanopartículas , Pneumonia , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ácido Poliglicólico/química , Levofloxacino/farmacologia , Quitosana/química , Glicóis , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Ácido Láctico/química , Antibacterianos/farmacologia , Bactérias/metabolismo , Nanopartículas/química
3.
Saudi J Biol Sci ; 31(3): 103942, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38327660

RESUMO

In the current study the assessment of the antimicrobial and phytochemical properties of Cassia fistula, Musa paradisiaca, Ficus religiosa and Murraya koenigii plants extracts was carried out. The antibacterial potential of these plants extracts was tested against S. aureus and E. coli. The Cassia fistula and Ficus religiosa leaves showed the larger zone of inhibition in aqueous and butanolic extract respectively against Escherichia coli. Musa paradisiaca and Murraya koenigii leaves showed larger zone of inhibition in ethanolic extract against S. aureus. Qualitative phytochemical analysis showed the presence of alkaloids, flavonoids, phenols, terpenoids, steroids, glycosides, saponins, carbohydrates, proteins and tannins in all extracts while phylobatannins, emodins, anthocyanins and leucoanthocyanins were not present in these extracts. Quantitative phytochemical analysis showed the highest alkaloid content in the Murraya koenigii leaves. Highest tannin content and flavonoid content was found in Ficus religiosa leaves, while highest phenolic content was found in case of Cassia fistula. In addition to this antioxidant potential of all the extracts was determined. Musa paradisiaca leaves showed highest antioxidant potential as compared to other plant extracts. In silico analysis of bioactive components present in plant extracts was performed by molecular docking. The rutin and Glu from Musa paradisiaca and Murraya koenigii respectively, were docked with Glycogen Synthase Kinase 3 beta (1GSK-3beta) protein. Quercetin and rutin from Cassia fistula and Ficus religiosa respectively, were docked with C- reactive protein (CRP). The tested bioactive compounds showed good binding affinity with significant number of hydrogen bonds and can be used as a good alternative of synthetic drugs to treat rheumatism and wounds.

4.
Pharmaceuticals (Basel) ; 16(11)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38004465

RESUMO

This study aimed to synthesize and characterize DTX-mPEG-PLA-NPs along with the development and validation of a simple, accurate, and reproducible method for the determination and quantification of DTX in mPEG-PLA-NPs. The prepared NPs were characterized using AFM, DLS, zetasizer, and drug release kinetic profiling. The RP-HPLC assay was developed for DTX detection. The cytotoxicity and anti-clonogenic effects were estimated using MTT and clonogenic assays, respectively, using both MCF-7 and MDA-MB-231 cell lines in a 2D and 3D culture system. The developed method showed a linear response, high precision, accuracy, RSD values of ≤2%, and a tailing factor ≤2, per ICH guidelines. The DTX-mPEG-PLA-NPs exhibited an average particle size of 264.3 nm with an encapsulation efficiency of 62.22%. The in vitro drug kinetic profile, as per the Krosmeyers-Peppas model, demonstrated Fickian diffusion, with initial biphasic release and a multistep sustained release over 190 h. The MTT assay revealed improved in vitro cytotoxicity against MCF-7 and MDA-MB-231 in the 2D cultures and MCF-7 3D mammosphere cultures. Significant inhibitions of the clonogenic potential of MDA-MB-231 were observed for all concentrations of DTX-mPEG-PLA-NPs. Our results highlight the feasibility of detecting DTX via the robust RP-HPLC method and using DTX-mPEG-PLA-NPs as a perceptible and biocompatible delivery vehicle with greater cytotoxic and anti-clonogenic potential, supporting improved outcomes in BC.

6.
Saudi J Biol Sci ; 30(2): 103556, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36698857

RESUMO

The new concept of functional foods has led to the varieties in the production of foods that provide not only basic nutrition, but can also warrant good health and longevity. This study deals with the production and evaluation of fortified yogurts' with Cinnamomum verum, Elettaria cardamomum, Beta vulgaris and Brassica oleracea. The qualitative and quantitative phytochemical analysis of above mentioned plant extracts before using them into the preparation of functional yoghurt was carried out. The sensory evaluation of enriched yogurts with plant extracts carried out using 9 point hedonic scale. Comparative analysis between enriched yogurts and plain yogurt was carried. The results indicated increase in ash contents, water holding capacity, titratable acidity, total soluble solids, total phenolic content, tannin content, and total flavonoid content in fortified yogurt as compared to plain yogurt. In addition to this fortified yogurts showed greater antioxidant and antibacterial activity in contrast to plain yogurt. However, moisture contents, pH and susceptibility to syneresis of yogurt decreases with the addition of plant extracts. Shelf life of plain and fortified yogurt was determined both at room and refrigerated temperature. The results revealed that shelf life of fortified yogurt was greater as compared to plain yogurt. In silico analysis was carried out by using the galaxy web software. The results indicated that bioactive compounds including ascorbic acid, sinapinic acid, cinnamaldehyde and linalool acetate present in the flavored yogurts binds with angiotensin converting enzyme. All enriched yogurts showed higher anti-Angiotensin converting enzyme activity as compared to plain-yogurt.

7.
Saudi J Biol Sci ; 29(12): 103483, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36389206

RESUMO

Cellulases involved in the hydrolysis of cellulose and plays a vital role in different industries like textile, detergent paper and Feed industry. Cellulases have been a prospective target for research by both the academic and industrial sectors because of the intricacy of the enzyme system and the enormous industrial potential. In the present work Thermomyces dupontii, which had previously been isolated and recorded as a promising cellulase producer were used. Both endoglucanases and betaglucosidases were purified to its homogeneity by ammonium sulfate followed by anion exchange and gel filtration chromatography. The recovery and purification fold for endoglucanases and betaglucosidases were 13.7, 10.7 % and 5.9, 2.7, respectively. The molecular weight of endoglucanases and betaglucosidases were estimated as 37 and 66 kDa on SDS-PAGE. Upon kinetic analysis the purified endoglucanases and betaglucosidases showed Km 0.63; 28.56 mg/ml and Vmax 82; 80 U/ml/min, respectively. Characterization revealed that enzyme was found to be acidophilic cellulase having optimal pH of 5.5 and 70 °C. Furthermore, cellulases were accelerated in the presence of Ca2+ and EDTA. The cellulases had activation energy (Ea) of -44.55; -50.02 kJ/mol for carboxy-methyl-cellulose hydrolysis and Enthalpy (ΔH) 42.20; 47.70 kJ/mol and entropy ΔS -5.1 and -5.7 kJ/mol for EG and BGL, respectively. In addition to this the enzyme had a secondary structure of protein as represented by FTIR spectrum The current study suggested that purified cellulases can be used as a detergent additive to improve washing. Furthermore, it shows the biostoning ability when applied on jean fabric.

8.
PLoS One ; 17(8): e0273685, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36037197

RESUMO

AIM: To identify the molecular basis of Congenital Hereditary Endothelial Dystrophy CHED caused by mutations in SLC4A11, in the consanguineous Pakistani families. METHODS: A total of 7 consanguineous families affected with Congenital Hereditary Endothelial Dystrophy were diagnosed and registered with the help of ophthalmologists. Blood samples were collected from affected and unaffected members of the enrolled families. Mutational analysis was carried out by DNA sequencing using both Sanger and Whole Exome Sequencing (WES). Probands of each pedigree from the 7 families were used for WES. Results were analyzed with the help of different bioinformatics tools. RESULTS: The sequencing results demonstrated three known homozygous mutations in gene SLC4A11 in probands of 7 families. These mutations p.Glu675Ala, p.Val824Met, and p.Arg158fs include 2 missense and 1 frameshift mutation. The mutations result in amino acids that were highly conserved in SLC4A11 across different species. The mutations were segregated with the disease phenotype in the families. CONCLUSION: This study reports 3 mutations in 7 families. One of the pathogenic mutations (p.R158fs) was identified for the first time in the Pakistani population. However, two mutations (p.Glu675Ala, p.Val824Met) were previously reported in two and one Pakistani family respectively. As these mutations segregate with the disease phenotype and bioinformatics tool also liable them as pathogenic, they are deemed as probable cause of underlying disease.


Assuntos
Distrofias Hereditárias da Córnea , Simportadores , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Antiporters/metabolismo , Boratos/metabolismo , Distrofias Hereditárias da Córnea/genética , Análise Mutacional de DNA , Humanos , Mutação , Paquistão , Linhagem , Sódio/metabolismo , Simportadores/genética
9.
Cell Mol Biol (Noisy-le-grand) ; 68(9): 51-56, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36905275

RESUMO

The study revealed enhanced production of α 1, 4 D glucan glucanohydrolase utilizing the synergistic phenomena of bacterial hetero-culture. For this purpose, 101 hetero-cultures were screened qualitatively and quantitatively. The bacterial hetero-culture showing the highest amylolytic potential was identified as Bacillus subtilis and Bacillus amyloliquefeciens by 16S rDNA sequencing technique. Different fermentation media were evaluated and M 5 gave maximum GGH production. Different physicochemical parameters like incubation time, temperature, initial pH and inoculum size was optimized. The optimal enzyme production was obtained at 24 h, 37oC, pH 7.0 and 3% inoculum size. Glucose (3%), ammonium sulphate (1.5%) and yeast extract (2.0%) was selected as best carbon and nitrogen source, respectively. The novelty of the present piece of research was the application of the hetero-culture technique for enhanced GGH production using submerged fermentation which was not experienced before with these strains.


Assuntos
Bacillus , Glucanos , Fermentação , Bacillus subtilis , Glucose , Concentração de Íons de Hidrogênio , Temperatura , Meios de Cultura , Carbono
10.
Protein Pept Lett ; 28(12): 1349-1364, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34749601

RESUMO

Lignocellulosic biomass, one of the most valuable natural resources, is abundantly present on earth. Being a renewable feedstock, it harbors a great potential to be exploited as a raw material, to produce various value-added products. Lignocellulolytic microorganisms hold a unique position regarding the valorization of lignocellulosic biomass as they contain efficient enzyme systems capable of degrading this biomass. The ubiquitous nature of these microorganisms and their survival under extreme conditions have enabled their use as an effective producer of lignocellulolytic enzymes with improved biochemical features crucial to industrial bioconversion processes. These enzymes can prove to be an exquisite tool when it comes to the eco-friendly manufacturing of value-added products using waste material. This review focuses on highlighting the significance of lignocellulosic biomass, microbial sources of lignocellulolytic enzymes and their use in the formation of useful products.


Assuntos
Biomassa , Hidrolases/química , Lignina/química , Hidrolases/metabolismo , Lignina/metabolismo
11.
PLoS One ; 16(8): e0255523, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34351937

RESUMO

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is one of the key targets for atherosclerosis drug development as its binding with low-density lipoprotein receptor leads to atherosclerosis. The protein-ligand interaction helps to understand the actual mechanism for the pharmacological action. This research aims to discover the best inhibitory candidates targeting PCSK9. To start with, reported ACE inhibitors were incorporated into pharmacophore designing using PharmaGist to produce pharmacophore models. Selected models were later screened against the ZINC database using ZINCPHARMER to define potential drug candidates that were docked with the target protein to understand their interactions. Molecular docking revealed the top 10 drug candidates against PCSK9, with binding energies ranging from -9.8 kcal·mol-1 to -8.2 kcal·mol-1, which were analyzed for their pharmacokinetic properties and oral bioavailability. Some compounds were identified as plant-derived compounds like (S)-canadine, hesperetin or labetalol (an antihypertensive drug). Molecular dynamics results showed that these substances formed stable protein-ligand complexes. (S)-canadine-PCSK9 complex was the most stable with the lowest RMSD. It was concluded that (S)-canadine may act as a potential inhibitor against atherosclerosis for the development of new PCSK9 inhibitory drugs in future in vitro research.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Ensaios de Triagem em Larga Escala/métodos , Simulação de Acoplamento Molecular , Inibidores de PCSK9 , Domínio Catalítico , Técnicas de Química Combinatória , Humanos , Modelos Moleculares , Pró-Proteína Convertase 9/química , Conformação Proteica
12.
Electron. j. biotechnol ; 51: 79-87, May. 2021. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1343441

RESUMO

BACKGROUND: At present, cellulases are the most important enzymes worldwide, and their demand has been increasing in the industrial sector owing to their notable hydrolysis capability. RESULTS: In the present study, contrary to conventional techniques, three physical parameters were statistically optimized for the production of cellulase by thermophilic fungi by using response surface methodology (RSM). Among all the tested thermophilic strains, the best cellulase producing fungus was identified as Talaromyces thermophilus ­ both morphologically and molecularly through 5.8S/ITS rDNA sequencing. The central composite design (CCD) was used to evaluate the interactive effect of the significant factors. The CCD was applied by considering incubation period, pH, and temperature as the model factors for the present investigation. A second-order quadratic model and response surface method revealed that the independent variables including pH 6, temperature 50 C, and incubation period 72 h significantly influenced the production of cellulases. The analysis of variance (ANOVA) indicated that the established model was significant (P 0.05) and showed the high adequacy of the model. The actual and predicted values of CMCase and FPase activity showed good agreement with each other and also confirmed the validity of the designed model. CONCLUSIONS: We believe the present findings to be the first report on cellulase production by exploiting Kans grass (Saccharum spontaneum) as a substrate through response surface methodology by using thermophilic fungus, Talaromyces thermophilus.


Assuntos
Talaromyces/metabolismo , Celulases/biossíntese , Análise de Variância , Saccharum , Fermentação , Temperatura Alta , Concentração de Íons de Hidrogênio
13.
Turk J Chem ; 45(1): 92-103, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679156

RESUMO

This study was conducted to investigate the physicochemical, phytochemical, in vitro antidiabetic and anticancer potential of Olea ferruginea R bark. After extraction using Soxhlet, in vitro antidiabetic and cytotoxic activity on human hepatocellular carcinoma (HepG2) cells was assessed by nonenzymatic glycosylation of hemoglobin assay, alpha-amylase inhibition assay, glucose uptake by yeast cells, and 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay, respectively, and gene expression via real-time polymerase chain reaction. Primary and secondary metabolites were present in the extractants; polyphenols (35.61 ± 0.03) and flavonoids (64.33 ± 0.35 ) in the chloroform; and polysaccharides in the ethanol (268.75 ± 0.34), and glycosaponins (78.01 ± 0.07) in the methanol. The chloroform extract exhibited maximum antidiabetic potential, showing inhibition of nonenzymatic glycosylation of hemoglobin (65%), and alpha-amylase inhibition (32%) with maximum percent glucose uptake by the ethanol extract (78%). Only the ethanol extract had dose-dependent cytotoxic potential against the HepG2 cells. After 24-h exposure to the ethanol-extract, the expression of protein kinase B (Akt) remained unchanged, while the expression of B-cell lymphoma 2 (BCL2) and BCL2 associated X (BAX) changed significantly. After 48-h exposure, the expression of Akt decreased significantly, while that of BCL2 and BAX increased significantly. Olea ferruginea R bark possessed in vitro antidiabetic potential and anticancer/cytotoxic effects, attributable to the decline in the prosurvival signals of the Akt signaling pathway.

14.
Biosci. j. (Online) ; 37: e37021, Jan.-Dec. 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1359538

RESUMO

Cellulase has myriad applications in various sectors like pharmaceuticals, textile, detergents, animal feed and bioethanol production, etc. The current study focuses on the isolation, screening and optimization of fungal strain through one factor at a time technique for enhanced cellulase production. In current study sixteen different fungal cultures were isolated and the culture which quantitatively exhibits higher titers of cellulase activity was identified both morphologically and molecularly by 18S rDNA and designated as Aspergillus niger ABT11. Different parameters like fermentation medium, volume, temperature, pH and nutritional components were optimized. The highest CMCase and FPase activities was achieved in 100ml of M5 medium in the presence of 1% lactose and sodium nitrate at 30 oC, pH5 after 72 hours. The result revealed A. niger can be a potential candidate for scale up studies.


Assuntos
Aspergillus niger , Celulase , Fermentação
15.
Biosci. j. (Online) ; 37: e37023, Jan.-Dec. 2021. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1359541

RESUMO

This study assessed the potential of termite gut inhabiting bacteria towards bioconversion of cellulosic waste into biofuel. Total seven bacterial isolates from the gut of Heterotermes indicola were isolated. Among all the isolates, HI-1 produced the largest zone upon primary screening. Untreated paper had more cellulose content (73.03%) than acid (0.5%) treated paper that was used as a lignocellulosic substrate for saccharification. Among all the isolates tested, glucose yield (1.08mg/mL) was high for HI-1 isolate. Several factors were considered for optimizing augmented glucose yield (8.57mg/mL) and growth (8.07×108cfu/mL), such as temperature 37°C, pH 4.5, 5% (w/v) substrate concentration, 6 % bacterial inoculum size, agitation 150 rpm with PEG 0.25 % and Ca2+ ions 0.002 g/L. Overall 8-fold increase in glucose yield was achieved. Enzyme activity of HI-1 showed higher endoglucanase 0.29 ± 0.01 (U/mL/min) and exoglucanase 0.15±0.01 (U/mL/min) activity under optimum conditions, mentioned above. temperature 37°C, pH 4.5, substrate concentration 5%, inoculum size 6%, surfactants PEG 0.01%, ions Ca2+(0.002g/L) and agitation (120 rpm). Simultaneous saccharification and fermentation (SSF) of hydrolyzed office paper yielded 5.43mg/mL bioethanol. According to 16S rRNA sequence homology, the bacterial isolate H1 was identified as Alcaligenes faecalis. Bioethanol production from office paper untreated waste proved an effective strategy. Bacteria having natural tendency towards cellulosic waste consumption are promising for bioconversion of cellulosic waste to valuable products.


Assuntos
Isópteros/microbiologia , Alcaligenes faecalis , Bioetanol
16.
Biosci. j. (Online) ; 37: e37022, Jan.-Dec. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1359872

RESUMO

Thyroid hormones play a significant role in normal human body growth. Abnormalities in thyroid stimulating hormone (TSH) levels can result in pregnancy loss due to miscarriages and intrauterine death (IUD). The objective of the study was to assess the levels of association of thyroid stimulating hormone with miscarriages and IUD. The descriptive study involving 110 samples between 18-40 years of age fulfilling inclusion criteria were sampled for TSH testing (2ml blood) after attaining their written informed consent. The mean age of participants was 29.49±4.26 year. The prevalence of hypothyroidism and hyperthyroidism was 3.64% and 2.73%, respectively. Complications like gestational hypertension, depression and oligomenorrhea were found prevalent in these females. Majority of females were taking high/low iodine than recommended iodine level (150mcg). This work shows that there is a significant association between pregnancy loss and disturbed TSH levels among pregnant females.


Assuntos
Tireotropina , Aborto Espontâneo , Dispositivos Intrauterinos , Gestantes , Hipertireoidismo , Hipotireoidismo
17.
Protein Pept Lett ; 28(3): 333-339, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32798372

RESUMO

BACKGROUND: The prevalence of the chronic metabolic disorder Type 2 diabetes mellitus (T2DM) is increasing steadily, and has even turned into an epidemic in some countries. T2DM results from defective responses to insulin and obesity is a major factor behind insulin resistance in T2DM. Insulin receptor substrate (IRS) proteins are adaptor proteins in the insulin receptor signalling pathway. The insulin signalling is controlled through tyrosine phosphorylation of IRS-1 and IRS-2, and dysregulation of IRS proteins signalling may lead to glucose intolerance and eventually insulin resistance. OBJECTIVE: In this work, we suggest that both glycosylation (O-GlcNAc modification) and phosphorylation of IRS-1 and -2 are involved in the pathogenesis of T2DM. METHODS: Phosphorylation and O-GlcNAc modifications (Ser1101 in IRS-1 and Ser1149 in IRS-2) proteins were determined experimentally by sandwich ELISA with specific antibodies and with bioinformatics tools. RESULTS: When IRS-1 (on Ser1101) and IRS-2 (Ser1149) become glycosylated following an increase in UDP-GlcNAc pools, it may contribute to insulin resistance. Whereas when the same (IRS-1 on Ser1101 and IRS-2 on Ser1149) are phosphorylated, the insulin signalling is inhibited. DISCUSSION: In this work OGlcNAc-modified proteins were specifically detected using O-Glc- NAc-specific antibodies, suggesting that elevated levels of O-GlcNAc-modified proteins are found, independently of their possible involvement in Advanced Glycation End products (AGEs). CONCLUSION: This study suggests a mechanism, which is controlled by posttranslational modifications, and may contribute to the pathogenesis of type II diabetes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Insulina/metabolismo , Transdução de Sinais , Feminino , Glicosilação , Humanos , Masculino , Fosforilação
18.
Biosci. j. (Online) ; 35(5): 1552-1559, sept./oct. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1049051

RESUMO

ß-glucosidase has wide spectrum of biotechnological applications in different industries including food, textile, laundry detergents, pulp and paper, pharmaceutical and biofuel industry. The present investigation related to isolation, screening, and process optimization of fungal strain for enhanced production of ß-glucosidase (BGL). For this purpose, different fungal stains were isolated from different sources including soil, fruits, bark of tree as well as from the compost. The screening of fungal strain for BGL production was carried out via submerged fermentation. All the tested strains were identified on the basis of micro and macroscopic features. The fungal strain having greater ability for BGL synthesis among tested ones wasidentified as Aspergillus niger and given the code SBT-15. The process parameter including fermentation media, temperature, pH, rate of fermentation, carbon and nitrogen sources, volume of media were optimized. Five different fermentation media were evaluatedM3medium gave maximum production. The optimal conditions for BGL production was 72 hours of incubation at 40°C, pH 6 and 50 ml fermentation medium. Glucose (1%) and ammonium sulphate(3%) were optimized as best carbon and nitrogen sources, respectively.


A ß-glicosidase possui amplo espectro de aplicações biotecnológicas em diferentes indústrias, incluindo alimentos, têxteis, detergentes para lavanderia, papel e celulose, indústria farmacêutica e de biocombustíveis, etc. A presente investigação relaciona-se ao isolamento e triagem e otimização de processos de cepas fúngicas para produção aumentada de ß- glucosidase (BGL). Para este efeito, diferentes manchas fúngicas foram isoladas a partir de diferentes fontes, incluindo solo, frutos, casca de árvore, bem como a partir do composto. A triagem da linhagem fúngica para produção de BGL foi realizada via fermentaçãosubmersa. Todas as cepas testadas foram identificadas com base em características micro e macroscópicas. A linhagem fúngica com maior capacidade de síntese de BGL entre os testados foi identificada como Aspergillus niger e recebeu o código SBT-15. O parâmetro do processo, incluindo meios de fermentação, temperatura, pH, taxa de fermentação, fontes de carbono e nitrogênio, volume de mídia foram otimizados. Cinco meios de fermentação diferentes foram avaliados. O meio M3 deu a produção máxima. As condições ótimas para a produção de BGL foram 72 horas de incubação a 40 ° C, pH 6 e 50ml de meio de fermentação. Glicose (1%) e sulfato de amônio (3%) foram otimizados como melhores fontes de carbono e nitrogênio, respectivamente.


Assuntos
Aspergillus niger , Fermentação , Fungos , Glucosidases
19.
Biosci. j. (Online) ; 35(4): 1237-1244, july/aug. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1048926

RESUMO

Industrialization has added extremely toxic metalloid arsenic into the environment which at high concentration severely threatens the biota. Naturally, some microbes possess the ability to bio-accumulate metals and also to transform arsenite (As III) a toxic form to a non-toxic arsenate As V. The present study aimed to isolate arsenic resistant bacterias from the arsenic contaminated soil and water. Among eleven bacterial isolates, three FAs 1, 4 and 9 exhibited tolerance against sodium arsenite at 100mM concentration by achieving growth of 7.48×109,1.57×109 and 2.23×109 C.F.U./ml, respectively. Optimization at differentconditions such as temperature, pH and arsenic concentration revealed high arsenic tolerance from isolate FAs 4 (5.33×108) at 37°C and FAs 1 (4.43×108 C.F.U./ml) at pH 7. Arsenic resistance at optimum conditions for the bacterial strains FAs 1, FAs 4 and FAs 9 showed maximum growth at 80mM concentration of arsenite. These bacterial isolates did not show redox ability to oxidize arsenite As III to arsenate As V. However bacterial isolates FAs 1, FAs 4 and FAs 9 were able to accumulate arsenic 39.16, 148 and 125 µ g/L on the 4th, 3rd and 5thday of incubation, respectively. The isolates FAs 1, FAs 4 and FAs 9 were identified as Gram negative non endospore forming rods. In future, these novel isolates possess a great potential in biotechnology field, as bioremediation of arsenic contaminated soil and water can be done by employing arsenic accumulating bacteria which is an eco-friendly and cost effective method.


A industrialização adicionou arsênico metalóide extremamente tóxico ao ambiente que, em alta concentração, ameaça severamente a biota. Naturalmente, alguns micróbios possuem a capacidade de bio-acumular metais e também transformar arsenito (As III) uma forma tóxica a um arsenato não-tóxico Como V. O presente estudo visa o isolamento de bactérias resistentes ao arsênico do solo contaminado com arsênico e água . Entre onze isolados bacterianos, três FAs 1, 4 e 9 exibiram tolerância à concentração de 100 mM de arseatura de sódio, obtendo crescimento de 7,48 × 109,157 × 109 e 2,23 × 109 C.F.U./ml, respectivamente. Otimização em diferentes condições como temperatura, pH e concentração de arsênio revelaram alta tolerância ao arsênico do isolado FAs 4 (5,33 × 108) a 37 ° C e FAs 1 (4,43 × 108 UFC / ml) em pH 7. Resistência ao arsênico em condições ótimas para as cepas bacterianas FAs 1, FAs 4 e FAs 9 apresentaram crescimento máximo na concentração de 80 mM de arsenito. Estes isolados bacterianos não mostraram capacidade redoxpara oxidar o arsenito As III para arseniar como V. No entanto, os isolados bacterianos FAs 1, FAs 4 e FAs 9 foram capazes de acumular arsênico 39,16, 148 e 125 µ g / L no 4º, 3º e 5º dia de incubação, respectivamente. Os isolados FAs 1, FAs 4 e FAs 9 foram identificados como bastonetes gram-negativos não endoscópicos. No futuro, esses novos isolados possuem um grande potencial no campo da biotecnologia, já que a biorremediação de solo e água contaminados com arsênico pode ser feita empregando-se bactérias que acumulam arsênico, o que é um método ecologicamente correto e econômico.


Assuntos
Arsênio , Biodegradação Ambiental , Poluição Ambiental , Bioacumulação
20.
Pol J Microbiol ; 68(1): 35-42, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31050251

RESUMO

The present study was carried out to reduce the size of silver nanoparticles (AgNPs) by optimizing physico-chemical conditions of the Aspergillus fumigatus BTCB10 growth based on central composite design (CCD) through response surface methodology (RSM). Variables such as a concentration of silver nitrate (mM), NaCl (%) and the wet weight of biomass (g) were controlled to produce spherical, monodispersed particles of 33.23 nm size, observing 78.7% reduction in size as compared to the initially obtained size that was equal to 356 nm. The obtained AgNPs exhibited negative zeta potential of -9.91 mV with a peak at 420 nm in the UV-Vis range whereas Fourier Transform Infrared (FT-IR) analysis identified O-H, C = C, C ≡ C, C-Br and C-Cl groups attached as capping agents. After conducting RSM experiments, a high nitrate reductase activity value of 179.15 nmol/h/ml was obtained; thus indicating a likely correlation between enzyme production and AgNPs synthesis. The F-value (significant at 3.91), non-significant lack of fit and determination coefficient (R2 = 0.7786) is representative of the good relation between the predicted values of response. We conclude that CCD is an effective tool in obtaining significant results of high quality and efficiency.The present study was carried out to reduce the size of silver nanoparticles (AgNPs) by optimizing physico-chemical conditions of the Aspergillus fumigatus BTCB10 growth based on central composite design (CCD) through response surface methodology (RSM). Variables such as a concentration of silver nitrate (mM), NaCl (%) and the wet weight of biomass (g) were controlled to produce spherical, monodispersed particles of 33.23 nm size, observing 78.7% reduction in size as compared to the initially obtained size that was equal to 356 nm. The obtained AgNPs exhibited negative zeta potential of ­9.91 mV with a peak at 420 nm in the UV-Vis range whereas Fourier Transform Infrared (FT-IR) analysis identified O­H, C = C, C ≡ C, C­Br and C­Cl groups attached as capping agents. After conducting RSM experiments, a high nitrate reductase activity value of 179.15 nmol/h/ml was obtained; thus indicating a likely correlation between enzyme production and AgNPs synthesis. The F-value (significant at 3.91), non-significant lack of fit and determination coefficient (R2 = 0.7786) is representative of the good relation between the predicted values of response. We conclude that CCD is an effective tool in obtaining significant results of high quality and efficiency.


Assuntos
Aspergillus fumigatus/metabolismo , Nanopartículas Metálicas/microbiologia , Nitrato Redutase/metabolismo , Nitrato de Prata/química , Biomassa , Microscopia de Força Atômica , Prata/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
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