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1.
Pediatr Res ; 92(3): 888-898, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34853430

RESUMO

AIM: Genetic variants contribute to the pathogenesis of bronchopulmonary dysplasia (BPD). The aim of this study is to evaluate the association of 45 SNPs with BPD susceptibility in a Turkish premature infant cohort. METHODS: Infants with gestational age <32 weeks were included. Patients were divided into BPD or no-BPD groups according to oxygen need at 28 days of life, and stratified according to the severity of BPD. We genotyped 45 SNPs, previously identified as BPD risk factors, in 192 infants. RESULTS: A total of eight SNPs were associated with BPD risk at allele level, two of which (rs4883955 on KLF12 and rs9953270 on CHST9) were also associated at the genotype level. Functional relationship maps suggested an interaction between five of these genes, converging on WNT5A, a member of the WNT pathway known to be implicated in BPD pathogenesis. Dysfunctional CHST9 and KLF12 variants may contribute to BPD pathogenesis through an interaction with WNT5A. CONCLUSIONS: We suggest investigating the role of SNPs on different genes which are in relation with the Wnt pathway in BPD pathogenesis. We identified eight SNPs as risk factors for BPD in this study. In-silico functional maps show an interaction of the genes harboring these SNPs with the WNT pathway, supporting its role in BPD pathogenesis. TRIAL REGISTRATION: NCT03467828. IMPACT: It is known that genetic factors may contribute to the development of BPD in preterm infants. Further studies are required to identify specific genes that play a role in the BPD pathway to evaluate them as a target for therapeutic interventions. Our study shows an association of BPD predisposition with certain polymorphisms on MBL2, NFKBIA, CEP170, MAGI2, and VEGFA genes at allele level and polymorphisms on CHST9 and KLF12 genes at both allele and genotype level. In-silico functional mapping shows a functional relationship of these five genes with WNT5A, suggesting that Wnt pathway disruption may play a role in BPD pathogenesis.


Assuntos
Displasia Broncopulmonar , Lectina de Ligação a Manose , Displasia Broncopulmonar/genética , Predisposição Genética para Doença , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Fatores de Transcrição Kruppel-Like/genética , Lectina de Ligação a Manose/genética , Oxigênio , Polimorfismo de Nucleotídeo Único , Sulfotransferases/genética , Via de Sinalização Wnt/genética
2.
Cell Stem Cell ; 28(11): 1922-1935.e5, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34529935

RESUMO

Little is known about how interactions of diet, intestinal stem cells (ISCs), and immune cells affect early-stage intestinal tumorigenesis. We show that a high-fat diet (HFD) reduces the expression of the major histocompatibility complex class II (MHC class II) genes in intestinal epithelial cells, including ISCs. This decline in epithelial MHC class II expression in a HFD correlates with reduced intestinal microbiome diversity. Microbial community transfer experiments suggest that epithelial MHC class II expression is regulated by intestinal flora. Mechanistically, pattern recognition receptor (PRR) and interferon-gamma (IFNγ) signaling regulates epithelial MHC class II expression. MHC class II-negative (MHC-II-) ISCs exhibit greater tumor-initiating capacity than their MHC class II-positive (MHC-II+) counterparts upon loss of the tumor suppressor Apc coupled with a HFD, suggesting a role for epithelial MHC class II-mediated immune surveillance in suppressing tumorigenesis. ISC-specific genetic ablation of MHC class II increases tumor burden cell autonomously. Thus, HFD perturbs a microbiome-stem cell-immune cell interaction that contributes to tumor initiation in the intestine.


Assuntos
Antígenos de Histocompatibilidade Classe II , Intestinos , Carcinogênese , Dieta Hiperlipídica , Células Epiteliais , Humanos
3.
J Microencapsul ; 38(6): 381-393, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34189998

RESUMO

AIM: This study aimed to synthesise quercetin- caffeic-acid phenethyl ester (CAPE)-co-loaded poly(lactic-co-glycolic-acid) (PLGA) nanoparticles (QuCaNP) and investigate their anti-cancer activity on human colorectal carcinoma HT-29 cells. METHODS: QuCaNPs were synthesised using single-emulsion (o/w) solvent evaporation method. Particle size, zeta potential, polydispersity index, in vitro release profile, and surface morphology of QuCaNPs were determined. Cytotoxicity, anti-migration, anti-proliferation and apoptotic activities of QuCaNPs were studied. RESULTS: Mean diameter of QuCaNP was 237.8 ± 9.670 nm, with a polydispersity index (PDI) of 0.340 ± 0.027. Encapsulation efficiency was 74.28% (quercetin) and 65.24% (CAPE). Particle size and drug content of QuCaNP remained stable for 30 days at -20 °C. The half-maximal inhibitory concentration (IC50) values of QuCaNP-treated HT-29 cells were calculated as 11.2 µg/mL (24 h) and 8.2 µg/mL (48 h). QuCaNP treatment increased mRNA levels of caspase-3 (2.38 fold) and caspase-9 (2-fold) and expressions of key proteins in the intrinsic apoptosis pathway in HT-29 cells. CONCLUSION: Overall, our results demonstrated QuCaNPs exhibits improved anti-cancer activity on HT-29 cells.


Assuntos
Neoplasias do Colo , Nanopartículas , Neoplasias do Colo/tratamento farmacológico , Ésteres , Humanos , Tamanho da Partícula , Ácido Poliglicólico , Quercetina/farmacologia
4.
Protein Pept Lett ; 28(10): 1138-1147, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34132177

RESUMO

BACKGROUND: Brucellosis is a zoonotic disease that causes serious economic losses due to factors, such as miscarriages and decreased milk yield in animals. Existing live vaccines have some disadvantages, so effective vaccines need to be developed with new technological approaches. OBJECTIVE: The primary objectives of this study were the expression and purification of recombinant Omp25 fusion protein from B. abortus, and the evaluation of the effect of the Omp25 protein on cell viability and inflammatory response. METHODS: The omp25 gene region was amplified by a polymerase chain reaction and cloned into a Pet102/D-TOPO expression vector. The protein expression was carried out using the prokaryotic expression system. The recombinant Omp25 protein was purified with affinity chromatography followed by GPC (Gel Permeation Chromatography). The MTS assay and cytokine-release measurements were carried out to evaluate cell viability and inflammatory response, respectively. RESULTS: It was determined that doses of the recombinant Omp25 protein greater than 0.1 µg/mL are toxic to RAW cells. Doses of 1 µg/mL and lower significantly increased inflammation due to Nitric Oxide (NO) levels. ELISA results showed that IFN-γ was produced in stimulated RAW 264.7 cells at a dose that did not affect the viability (0.05 µg/mL). However, IL-12, which is known to have a dual role in the activation of macrophages, did not show a statistically significant difference at the same dose. CONCLUSION: Studies on cell viability and Th1-related cytokine release suggest Omp25 protein to be a promising candidate molecule for vaccine development.


Assuntos
Brucella abortus/genética , Brucelose/tratamento farmacológico , Proteínas de Membrana/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Vacinas Sintéticas/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Escherichia coli/química , Escherichia coli/genética , Humanos , Imunogenicidade da Vacina , Proteínas de Membrana/química , Proteínas de Membrana/genética , Camundongos , Óxido Nítrico/metabolismo , Células RAW 264.7 , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Desenvolvimento de Vacinas , Vacinas Sintéticas/química , Vacinas Sintéticas/genética
5.
Pharm Dev Technol ; 25(6): 757-766, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32192406

RESUMO

Quercetin (Qu) is a natural flavonoid present in many commonly consumed food items. The dietary phytochemical quercetin prevents tumor proliferation and is a potent therapeutic cancer agent. The purpose of this study was to synthesize and characterize quercetin-loaded poly(lactic-co-glycolic acid) nanoparticles (Qu1NP, Qu2NP, and Qu3NP) with different size and encapsulation properties and to evaluate their in vitro activity on C6 glioma cells. Nanoparticles were synthesized by single emulsion solvent evaporation method. Then, particle size, zeta potential, polydispersity index and encapsulation efficiency of nanoparticles were determined. Particle size of Qu1NP, Qu2NP, and Qu3NPs were determined as 215.2 ± 6.2, 282.3 ± 7.9, and 584.5 ± 15.2 nm respectively. Treating C6 glioma cells with all nanoparticle formulations effectively inhibited the cell proliferation. Qu1NPs were showed the lowest IC50 value in 48 h with 29.9 µg/ml and achieved higher cellular uptake among other nanoparticles and Qu. Additionally, 48-h treatment with Qu1NPs significantly decreased MDA level (14.90 nmol/µg protein) on C6 glioma cells which is related to reduced oxidative stress in cells. Findings of this study revealed that quercetin's cellular uptake and anti-oxidant activity is improved by small-sized Qu1NPs in C6 glioma cells.


Assuntos
Antioxidantes/toxicidade , Citotoxinas/toxicidade , Glioma/metabolismo , Nanopartículas/metabolismo , Nanopartículas/toxicidade , Quercetina/toxicidade , Animais , Antioxidantes/farmacocinética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Citotoxinas/farmacocinética , Glioma/tratamento farmacológico , Tamanho da Partícula , Quercetina/farmacocinética , Ratos
6.
Artif Cells Nanomed Biotechnol ; 47(1): 319-329, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30688095

RESUMO

The aim of this study was to evaluate anti-cancer properties of hesperetin (Hsp) and hesperetin-loaded poly(lactic-co-glycolic acid) nanoparticles (HspNPs) for glioblastoma treatment. Nanoparticles prepared by single emulsion method had a size of less than 300 nm with 70.7 ± 3.9% reaction yield and 26.4 ± 1.1% Hsp loading capacity. Treatment of C6 glioma cells with HspNPs for 24 and 48 h resulted in dose- and time-dependent decrease in cell viability, with approximate IC50 of 28 and 21 µg/mL, respectively (p = .036 for 24 h, p = .025 for 48 h). The percentage of PCNA positive cells decreased to 20% and 10%, respectively, for Hsp- and HspNP-treated cells at concentration of 100 µg/mL. Treatment with increasing concentrations of HspNPs (25, 50, 75 and 100 µg/mL) resulted in 9.1-, 7-, 12.5- and 12.7-fold in increase in apoptotic cell number. Optimum doses of Hsp and HspNPs were found to increase oxidative damage in C6 glioma cells. MDA levels, an indicator of lipid peroxidation, were found to be significantly elevated at 75 and 100 µg/mL exposure concentration of HspNPs with (p = .002) and (p = .018), respectively for 48-h treatment. The results obtained with this study showed biocompatible polymeric nanoparticle systems has great advantages to enhance anti-cancer activity and poor solubility of therapeutic agents. Overall our findings suggest that Hsp-loaded PLGA nanoparticle systems showed significant anti-cancer activity and HspNPs could be used as promising novel anti-cancer agent.


Assuntos
Portadores de Fármacos/química , Glioma/patologia , Hesperidina/química , Hesperidina/farmacologia , Nanopartículas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Humanos , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Solubilidade , Superóxido Dismutase/metabolismo
7.
Cell Stem Cell ; 22(5): 769-778.e4, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29727683

RESUMO

Diet has a profound effect on tissue regeneration in diverse organisms, and low caloric states such as intermittent fasting have beneficial effects on organismal health and age-associated loss of tissue function. The role of adult stem and progenitor cells in responding to short-term fasting and whether such responses improve regeneration are not well studied. Here we show that a 24 hr fast augments intestinal stem cell (ISC) function in young and aged mice by inducing a fatty acid oxidation (FAO) program and that pharmacological activation of this program mimics many effects of fasting. Acute genetic disruption of Cpt1a, the rate-limiting enzyme in FAO, abrogates ISC-enhancing effects of fasting, but long-term Cpt1a deletion decreases ISC numbers and function, implicating a role for FAO in ISC maintenance. These findings highlight a role for FAO in mediating pro-regenerative effects of fasting in intestinal biology, and they may represent a viable strategy for enhancing intestinal regeneration.


Assuntos
Envelhecimento , Jejum/metabolismo , Ácidos Graxos/metabolismo , Homeostase , Intestinos/citologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Animais , Células Cultivadas , Camundongos , Camundongos Endogâmicos , Oxirredução
8.
J Mol Graph Model ; 74: 344-351, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28477574

RESUMO

Lactate dehydrogenase (LDH) is an important metabolic enzyme in glycolysis and it has been considered as the main energy source in many organisms including apicomplexan parasites. Differences at the active site loop of the host and parasite LDH's makes this enzyme an attractive target for drug inhibitors. In this study, five amino acid insertions in the active site pocket of Theileria annulata LDH (TaLDH) were deleted by PCR-based site-directed mutagenesis, expression and activity analysis of mutant and wild type TaLDH enzymes were performed. Removal of the insertion at the active site loop caused production of an inactive enzyme. Furthermore, structures of wild and mutant enzymes were predicted by comparative modeling and the importance of the insertions at the active site loop were also assigned by molecular docking and dynamics simulations in order to evaluate essential role of this loop for the enzymatic activity. Pentapeptide insertion removal resulted in loss of LDH activity due to deletion of Trp96 and conformational change of Arg98 because of loop instability. Analysis of wild type and mutant enzymes with comparative molecular dynamics simulations showed that the fluctuations of the loop residues increase in mutant enzyme. Together with in silico studies, in vitro results revealed that active site loop has a vital role in the enzyme activity and our findings promise hope for the further drug design studies against theileriosis and other apicomplexan parasite diseases.


Assuntos
L-Lactato Desidrogenase/química , Oligopeptídeos/química , Proteínas de Protozoários/química , Sequência de Aminoácidos , Sequência de Bases , Domínio Catalítico , Escherichia coli , Ligação de Hidrogênio , L-Lactato Desidrogenase/genética , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , Conformação Proteica em alfa-Hélice , Proteínas de Protozoários/genética , Ácido Pirúvico/química , Theileria annulata/enzimologia
9.
Mol Biotechnol ; 58(4): 256-67, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26921192

RESUMO

Theileria annulata is a parasite that causes theileriosis in cattle. Reports about drug resistance made essential to develop new drug. LDH of Theileria schizonts is the vital enzyme for its anaerobic metabolism. TaLDH gene was first cloned into pGEM-T cloning vector with two introns in our previous study. Here we report cloning of TaLDH without introns into pLATE 31 vector in E. coli BL21(DE3). Protein was in an inactive form. Two mutations were fixed to express the active protein. Protein was purified by affinity chromatography and evaluated by SDS-PAGE and size exclusion chromatography. Optimum pH of enzyme was performed in pH 7.5, and enzyme was stabilized at 20-40 °C. Enzyme kinetics of recombinant TaLDH were found to be in the direction of pyruvate to lactate K m 0.1324 and K i 4.295 mM, k cat, 44.55/s and k cat /K m, 3.3693 × 10(5)/M/s. 3D structure of TaLDH was predicted, and possible drug binding sites were determined by homology modelling.


Assuntos
L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Theileria annulata/enzimologia , Sítios de Ligação , Simulação por Computador , Estabilidade Enzimática , Modelos Moleculares , Mutação , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia Estrutural de Proteína , Theileria annulata/genética
10.
Mol Biotechnol ; 56(8): 689-96, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24664479

RESUMO

Tropical theileriosis is a disease caused by infection with an apicomplexan parasite, Theileria annulata, and giving rise to huge economic losses. In recent years, parasite resistance has been reported against the most effective antitheilerial drug used for the treatment of this disease. This emphasizes the need for alternative methods of treatment. Enolase is a key glycolytic enzyme and can be selected as a macromolecular target of therapy of tropical theileriosis. In this study, an intron sequence present in T. annulata enolase gene was removed by PCR-directed mutagenesis, and the gene was first cloned into pGEM-T Easy vector and then subcloned into pLATE31 vector, and expressed in Escherichia coli cells. The enzyme was purified by affinity chromatography using Ni-NTA agarose column. Steady-state kinetic parameters of the enzyme were determined using GraFit 3.0. High quantities (~65 mg/l of culture) of pure recombinant T. annulata enolase have been obtained in a higly purified form (>95 %). Homodimer form of purified protein was determined from the molecular weights obtained from a single band on SDS-PAGE (48 kDa) and from size exclusion chromatography (93 kDa). Enzyme kinetic measurements using 2-PGA as substrate gave a specific activity of ~40 U/mg, K m: 106 µM, kcat: 37 s(-1), and k cat/K m: 3.5 × 10(5) M(-1) s(-1). These values have been determined for the first time from this parasite enzyme, and availability of large quantities of enolase enzyme will facilitate further kinetic and structural characterization toward design of new antitheilerial drugs.


Assuntos
Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Theileria annulata/enzimologia , Theileria annulata/genética , Animais , Antiprotozoários/farmacologia , Sequência de Bases , Biotecnologia , Bovinos , Clonagem Molecular , DNA de Protozoário/genética , Desenho de Fármacos , Genes de Protozoários , Íntrons , Cinética , Dados de Sequência Molecular , Peso Molecular , Fosfopiruvato Hidratase/química , Estrutura Quaternária de Proteína , Proteínas de Protozoários/química , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Theileria annulata/efeitos dos fármacos , Theileriose/tratamento farmacológico , Theileriose/parasitologia
11.
Mol Biotechnol ; 54(2): 602-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23011788

RESUMO

One of the most important step in structure-based drug design studies is obtaining the protein in active form after cloning the target gene. In one of our previous study, it was determined that an internal Shine-Dalgarno-like sequence present just before the third methionine at N-terminus of wild type lactate dehydrogenase enzyme of Plasmodium falciparum prevent the translation of full length protein. Inspection of the same region in P. vivax LDH, which was overproduced as an active enzyme, indicated that the codon preference in the same region was slightly different than the codon preference of wild type PfLDH. In this study, 5'-GGAGGC-3' sequence of P. vivax that codes for two glycine residues just before the third methionine was exchanged to 5'-GGAGGA-3', by mimicking P. falciparum LDH, to prove the possible effects of having an internal SD-like sequence when expressing an eukaryotic protein in a prokaryotic system. Exchange was made by site-directed mutagenesis. Results indicated that having two glycine residues with an internal SD-like sequence (GGAGGA) just before the third methionine abolishes the enzyme activity due to the preference of the prokaryotic system used for the expression. This study emphasizes the awareness of use of a prokaryotic system to overproduce an eukaryotic protein.


Assuntos
Células Eucarióticas/metabolismo , L-Lactato Desidrogenase/genética , Mutação , Plasmodium falciparum/genética , Células Procarióticas/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Códon , Células Eucarióticas/enzimologia , Expressão Gênica , Glicina/genética , Glicina/metabolismo , L-Lactato Desidrogenase/metabolismo , Metionina/genética , Metionina/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida/métodos , Plasmodium falciparum/metabolismo , Células Procarióticas/enzimologia , Alinhamento de Sequência
12.
Vesalius ; 16(1): 41-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20977154

RESUMO

Cholera spread all over the world starting from India and made major outbreaks. Cholera, a highly effective disease, also had been a pioneer effect on taking health measures worldwide.The first international health organization and health conferences organized in different countries to determine preventive measures and treatments for cholera. In this article, preventive measures and treatments for cholera in the 19th century in the Ottoman period were analyzed according to Republic of Turkey Prime Ministry Ottoman Archives and compared with the current methods.


Assuntos
Cólera/história , Cólera/prevenção & controle , Cólera/terapia , Controle de Doenças Transmissíveis/história , História do Século XIX , Humanos , Império Otomano , Medicina Preventiva/história
13.
Acta Orthop Traumatol Turc ; 44(6): 469-75, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21358254

RESUMO

OBJECTIVES: We aimed to evaluate the effectiveness of the consent process and the retention of relevant information in patients with orthopedic trauma and those undergoing elective surgery. METHODS: The study enrolled 142 consecutive patients (79 women, 63 men; mean age 52.02±20.05 years) undergoing either elective or trauma-related surgery. The patients were introduced to the consent process, which involves a verbal and written explanation of the orthopedic condition, surgical procedure, and intraoperative and postoperative risks. At postoperative 1-3 days, patients were asked to recall the orthopedic condition, procedure they underwent, and risks of the surgery. RESULTS: The rate of recall by patients was 131/142 patients (92.3%) for diagnosis, 86/142 patients (60.6%) for surgical procedure, and 32/142 patients (22.5%) for potential complications. Fifty-nine patients (41.5%) could not recall any potential complications. Gender did not influence the ability to describe the operation or potential complications (p>0.05). Advanced age negatively affected recall of information about the surgery and complications (p<0.01), and educational level was correlated with the recall rate (p<0.05). Forty-two patients (29.6%) claimed to have read the consent form before signing it. A greater percentage of patients undergoing elective surgery had read the consent form (p<0.05). Rate of not recalling any potential complications was higher in the trauma group compared with the elective surgery group (p<0.01). CONCLUSION: Patients had poor retention of information presented during the consent procedure. Further attention should be focused on enhancing patients' understanding of several components of the informed consent process for surgery.


Assuntos
Consentimento Livre e Esclarecido , Rememoração Mental , Procedimentos Ortopédicos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Artroplastia , Escolaridade , Procedimentos Cirúrgicos Eletivos , Feminino , Humanos , Consentimento Livre e Esclarecido/psicologia , Consentimento Livre e Esclarecido/normas , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos/legislação & jurisprudência , Período Pré-Operatório , Adulto Jovem
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