RESUMO
We propose a novel, to the best of our knowledge, method to estimate the thickness and refractive index of a thin film by analyzing the reflectance as a function of the incidence angle. In most cases, interference fringes cannot be obtained from a film within a practical angular range unless it is much thicker than the wavelength. This problem was solved by adopting a high-index material as the medium of incidence, in which case several cycles of interference fringes were observed within a small range of incidence angles near the critical angle, allowing a fringe analysis. Consequently, the thicknesses, as well as the refractive indices of dielectric thin films, could be estimated. Our proposed method gave uncertainties of 20 nm and 0.0004 for the thickness and refractive index measurements, respectively.
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We demonstrate the quantitative pressure measurement of gas molecules in the mid-infrared using chip-based supercontinuum and cepstrum analysis without additional measurements for baseline normalization. A supercontinuum generated in an on-chip waveguide made of chalcogenide glass having high nonlinearity passes through CO gas and provides a transmission spectrum. The gas absorption information is deconvoluted from the original supercontinuum spectral information containing temporal fluctuation by cepstrum analysis and extracted simply by applying a bandpass filter in the temporal domain. The gas pressure estimated from the extracted absorption information is consistent with the value measured by a pressure gauge within a difference of 1.25%, despite spectral fluctuations in the supercontinuum baseline comparable to the spectral depth of the gas absorption lines.
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Fibroblast growth factor 21 (FGF21) has pharmaceutical potential against obesity-related metabolic disorders, including non-alcoholic fatty liver disease. Since thermal stability is a desirable factor for therapeutic proteins, we investigated the thermal behavior of human FGF21. FGF21 remained soluble after heating; thus, we examined its temperature-induced structural changes using circular dichroism (CD). FGF21 showed inter-convertible temperature-specific CD spectra. The CD spectrum at 100 °C returned to that at 20 °C when the heated FGF21 solution was cooled. Through loop swapping, the connecting loop between ß10 and ß12 in FGF21 was revealed to be associated with the unique thermal behavior of FGF21. According to surface plasmon resonance (SPR) experiments, in vitro cell-based assays, and model high-fat diet (HFD)-induced obesity studies, heated FGF21 maintained biological activities that were comparable to those of non-heated and commercial FGF21s. Based on sequence comparison and structural analysis, five point-mutations were introduced into FGF21. Compared with the wild type, the heated FGF21 variant displayed improved therapeutic potential in terms of body weight loss, the levels of hepatic triglycerides and lipids, and the degree of vacuolization of liver in HFD-fed mice.
Assuntos
Calefação , Hepatopatia Gordurosa não Alcoólica , Humanos , Animais , Camundongos , Fígado/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Dieta Hiperlipídica , Camundongos Endogâmicos C57BLRESUMO
Dietary uptake of folic acid (FA) improves cartilage regeneration. In this work, we discovered that three days of FA treatment is highly effective for promoting chondrogenic differentiation of tonsil-derived mesenchymal stem cells (TMSCs). In a three-dimensional pellet culture, the levels of typical chondrogenic biomarkers, sulfated glycosaminoglycan, proteoglycan, type II collagen (COL II), SRY box transcription factor 9 (SOX 9), cartilage oligomeric matrix protein (COMP), and aggrecan (ACAN) increased significantly in proportion to FA concentration up to 30 µM. At the mRNA expression level, COL II, SOX 9, COMP, and ACAN increased 3.6-6.0-fold with FA treatment at 30 µM compared with the control system that did not receive FA treatment, and the levels with FA treatment were 1.6-2.5 times greater than those in the kartogenin-treated positive control system. FA treatment did not increase type I collagen α1 (COL I α1), an osteogenic biomarker which is a concern with most chondrogenic promoters. At the high FA concentration of 100 µM, significant decreases in chondrogenic biomarkers were observed, which might be related to DNA methylation. A thermogel system incorporating TMSCs and FA provided sustained release of FA over several days, similar to the FA treatment. The thermogel system confirmed the efficacy of FA in promoting chondrogenic promotion of TMSCs. The increased nuclear translocation of core-binding factor ß subunit (CBFß) and the runt-related transcription factor 1 (RUNX1) expression after FA treatment, together with molecular docking studies, suggest that the chondrogenic enhancement mechanism of FA is mediated by CBFß and RUNX1.
Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core , Ácido Fólico , Biomarcadores/metabolismo , Diferenciação Celular , Células Cultivadas , Condrócitos/metabolismo , Condrogênese , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Ácido Fólico/metabolismo , Simulação de Acoplamento MolecularRESUMO
AmpC BER is an extended-spectrum (ES) class C ß-lactamase with a two-amino-acid insertion in the H10 helix region located at the boundary of the active site compared with its narrow spectrum progenitor. The crystal structure of the wild-type AmpC BER revealed that the insertion widens the active site by restructuring the flexible H10 helix region, which is the structural basis for its ES activity. Besides, two sulfates originated from the crystallization solution were observed in the active site. The presence of sulfate-binding subsites, together with the recognition of ring-structured chemical scaffolds by AmpC BER, led us to perform in silico molecular docking experiments with halisulfates, natural products isolated from marine sponge. Inspired by the snug fit of halisulfates within the active site, we demonstrated that halisulfate 3 and 5 significantly inhibit ES class C ß-lactamases. Especially, halisulfate 5 is comparable to avibactam in terms of inhibition efficiency; it inhibits the nitrocefin-hydrolyzing activity of AmpC BER with a Ki value of 5.87 µM in a competitive manner. Furthermore, halisulfate 5 displayed moderate and weak inhibition activities against class A and class B/D enzymes, respectively. The treatment of ß-lactamase inhibitors (BLIs) in combination with ß-lactam antibiotics is a working strategy to cope with infections by pathogens producing ES ß-lactamases. Considering the emergence and dissemination of enzymes insensitive to clinically-used BLIs, the broad inhibition spectrum and structural difference of halisulfates would be used to develop novel BLIs that can escape the bacterial resistance mechanism mediated by ß-lactamases.
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Curcumin is a yellow-colored ingredient in dietary spice turmeric ( Curcuma longa Linn). This nontoxic polyphenol has antitumor, anti-inflammatory, apoptotic, and antioxidant activities. The ingested curcumin is reduced to multihydrated forms with more potent therapeutic potentials by the curcumin reductase (CurA) from commensal Escherichia coli. In this study, we demonstrated that Vibrio vulnificus CurA ( VvCurA) with 87% sequence similarity to the E. coli CurA exhibits the curcumin-reducing activity through spectrophotometric detection of NADPH oxidation and high performance liquid chromatographic analysis of curcumin consumption and product generation. Afterward, we determined the crystal structures of VvCurA and the VvCurA/NADPH complex, and made the in silico model of the VvCurA/NADPH/curcumin ternary complex through induced fit docking. Based on structural information, active site residues that play critical roles in catalysis have been identified and characterized by mutational and kinetic studies, leading us to propose the reaction mechanism of CurA.
Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Curcumina/metabolismo , Oxirredutases/química , Oxirredutases/metabolismo , Vibrio vulnificus/enzimologia , Proteínas de Bactérias/genética , Biocatálise , Domínio Catalítico , Curcumina/química , Cinética , Simulação de Acoplamento Molecular , NADP/metabolismo , Oxirredutases/genética , Vibrio vulnificus/química , Vibrio vulnificus/genéticaRESUMO
Despite the increasing prevalence of inflammatory bowel disease (IBD), classified as immune-mediated disorders, the exact biological mechanisms leading to its development are undetermined, and treatment strategies remain elusive. Probiotics have been proposed as potential alternatives for treating IBD. The purpose of this research was to find therapeutic candidates of probiotics for colitis. We adopted dextran sulfate sodium (DSS)-induced colitis model to demonstrate the therapeutic effects of ID-JPL934, a mixture of three live bacterial strains at a 1:1:1 ratio: Lactobacillus johnsonii IDCC9203, Lactobacillus plantarum IDCC3501, and Bifidobacterium animalis subspecies lactis IDCC4301, on IBD. The severity was scored according to the disease activity index (DAI) for colitis by observing body weight (BW) and stool status of each mouse once a day. BALB/c mice given 3.5% DSS in drinking water suffered from symptoms of colitis such as weight loss, diarrhea, and bloody excrement. In our study, administration of ID-JPL934 reduced the DAI scores in a dose-dependent manner, and treatments with ID-JPL934 108 and 109 colony-forming unit per mouse per day showed similar inhibition compared with those of sulfasalazine 500 mg per kg BW per day. Moreover, the contraction of colon length improved. ID-JPL934 also suppressed inflammatory lesions such as infiltration of immune cells in mucosa and submucosa, severe crypt damage, and loss of goblet and epithelial cells on the histological analysis. These results might be due to downregulation of the expression of proinflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-1ß, and IL-6. From these results, ID-JPL934 might be an effective therapeutic candidate for IBD.
Assuntos
Colite/tratamento farmacológico , Citocinas/genética , Probióticos/administração & dosagem , Animais , Bifidobacterium/fisiologia , Colite/induzido quimicamente , Colite/genética , Colite/imunologia , Citocinas/imunologia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Lactobacillus/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologiaRESUMO
Osteoarthritis is a disease that affects the articular cartilage and osseous tissue, and can be worsened by aging, overweight status, and post-traumatic arthritis. The present study aimed to evaluate the effect of ID-CBT5101 (tyndallized Clostridium butyricum) on bone metabolism and the inflammatory response in a monosodium iodoacetate-induced rat model of osteoarthritis. ID-CBT5101 was administered orally at doses of 108 or 1010 CFU/day for 2 weeks before direct injection of monosodium iodoacetate (3 mg/50 µl of 0.9% saline) into the intra-articular space of the rats' right knees. The rats subsequently received the same doses of oral ID-CBT5101 for another 4 weeks. We evaluated the treatment effects based on serum biomarkers, mRNA expression, morphological and histopathological analyses of the knee joints, and weight-bearing distribution analysis. Compared with those in control rats, the ID-CBT5101 treatments significantly reduced the serum concentration of inflammation and bone metabolism markers (i.e., COX-2, IL-6, LTB4, and COMP), and significantly increased the concentration of IFN-γ and glycosaminoglycans. In addition, the ID-CBT5101 treatments inhibited the mRNA expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases (i.e., MMP-2, MMP-3, MMP-9, MMP-13, TIMP-1, and TIMP-2). Furthermore, the ID-CBT5101 treatments effectively preserved the knee cartilage and synovial membrane, and significantly decreased the amount of fibrous tissue. Moreover, compared with that of the negative control group, the ID-CBT5101 treatments increased the weight-bearing distribution by ≥20%. The results indicate that ID-CBT5101 prevented and alleviated osteoarthritis symptoms. Thus, ID-CBT5101 may be a novel therapeutic option for the management of osteoarthritis.
Assuntos
Clostridium butyricum , Iodoacetatos/efeitos adversos , Traumatismos do Joelho/tratamento farmacológico , Osteoartrite/tratamento farmacológico , Administração Oral , Animais , Vacinas Bacterianas , Osso e Ossos/patologia , Citocinas , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Inflamação/tratamento farmacológico , Articulação do Joelho/patologia , Masculino , Metaloproteinases da Matriz/metabolismo , Metaloproteases/metabolismo , RNA Mensageiro/metabolismo , RatosRESUMO
ß-Lactamase-mediated resistance to ß-lactam antibiotics has been significantly threatening the efficacy of these clinically important antibacterial drugs. Although some ß-lactamase inhibitors are prescribed in combination with ß-lactam antibiotics to overcome this resistance, the emergence of enzymes resistant to current inhibitors necessitates the development of novel ß-lactamase inhibitors. In this study, we evaluated the inhibitory effect of dinucleotides on an extended-spectrum class C ß-lactamase, AmpC BER. Of the dinucleotides tested, NADPH, a cellular metabolite, decreased the nitrocefin-hydrolyzing activity of the enzyme with a Ki value of 103 µM in a non-covalent competitive manner. In addition, the dissociation constant (KD) between AmpC BER and NADPH was measured to be 40 µM. According to our in vitro susceptibility study based on growth curves, NADPH restored the antibacterial activity of ceftazidime against a ceftazidime-resistant Escherichia coli BER strain producing AmpC BER. Remarkably, a single dose of combinatory treatment with NADPH and ceftazidime conferred marked therapeutic efficacy (100% survival rate) in a mouse model infected by the E. coli BER strain although NADPH or ceftazidime alone failed to prevent the lethal bacterial infection. These results may offer the potential of the dinucleotide scaffold for the development of novel ß-lactamase inhibitors.
Assuntos
Proteínas de Bactérias/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , NADP/farmacologia , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Ceftazidima/administração & dosagem , Ceftazidima/farmacologia , Cefalosporinas/metabolismo , Modelos Animais de Doenças , Quimioterapia Combinada/métodos , Inibidores Enzimáticos/administração & dosagem , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Hidrólise , Indicadores e Reagentes/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , NADP/administração & dosagem , Análise de Sobrevida , Resultado do Tratamento , beta-LactamasesRESUMO
We determined the effect of ketosis treatment with propylene glycol (PG) or PG plus l-carnitine and methionine (Metabolase®, Fatro, Bologna, Italy) on the resolution, postpartum health, milk yield, and reproductive performances of dairy cows. Blood from 475 Holstein cows was collected weekly until 4 weeks after calving to measure blood ß-hydroxybutyrate (BHBA) concentrations. Cows with blood BHBA concentration ≥1.2 mmol/L were diagnosed with ketosis and were enrolled. One hundred and fifty cows diagnosed with ketosis were randomly assigned to three treatment groups (Day 0): (1) PG (300 g, PO) for 3 days (PG group, n = 50), (2) PG (300 g, PO) plus l-carnitine (1.25 g) plus methionine (5 g, IV) for 3 days (PG + CM group, n = 50), and (3) no treatment (control group, n = 50). On Day 3, blood was collected to evaluate whether the ketosis had resolved. Cows in the PG and PG + CM groups with blood BHBA ≥1.2 mmol/L were retreated for an additional 2 days, and then blood BHBA concentration was evaluated on Days 5 and 10. Blood glucose and haptoglobin concentrations, rumen fill score (RFS), and body condition score (BCS) were measured on Days 0, 3, 5, and 10. Postpartum complications, milk yield during the first 2 months, and reproductive outcomes were evaluated. The probability of resolution from ketosis was higher (P < 0.05) in the PG + CM group than in the control group on Days 3, 5, and 10 (odds ratio: 2.6-6.3). Blood BHBA in the PG + CM group was lower (P < 0.05) than that of the control group on Days 3 and 5, whereas blood glucose in the PG + CM group was higher (P < 0.05) than that of the control group on Days 3 and 5. RFS in the PG and PG + CM groups was higher than that of the control group on Day 10 (P < 0.01), while BCS loss from Day 0-10 in the control group was higher than those of the PG and PG + CM groups (P < 0.05). Milk yields on the 30th and 60th days postpartum were higher in the PG + CM group than the control and PG groups (P < 0.05). Postpartum complications and intervals between calving and first postpartum insemination or pregnancy did not differ among the groups (P > 0.05). In conclusion, treatment of dairy cows with PG plus l-carnitine and methionine improved the chances of resolution of ketosis and increased milk yield, while affecting neither the incidence of postpartum complications nor reproductive performance.
Assuntos
Carnitina/uso terapêutico , Doenças dos Bovinos/tratamento farmacológico , Cetose/veterinária , Lactação/fisiologia , Metionina/uso terapêutico , Propilenoglicol/uso terapêutico , Ácido 3-Hidroxibutírico/sangue , Animais , Carnitina/administração & dosagem , Bovinos , Feminino , Haptoglobinas/metabolismo , Metionina/administração & dosagem , Leite/fisiologia , Período Pós-Parto , Gravidez , Propilenoglicol/administração & dosagemRESUMO
IDP-73152, a novel inhibitor of a bacterial peptide deformylase, was recently approved as a new, investigational drug in Korea for the clinical management of infections caused by Gram positive bacteria. The objective of this study was to develop/validate a simple and robust analytical method for the determination of IDP-73152 in plasma samples from rodents and humans, and to assess the feasibility of the assay for use in pharmacokinetic studies using animal models. Plasma samples were processed using a standard method for protein precipitation and an aliquot of the extract then injected onto an UHPLC-MS/MS system. The drug and IDP-117293, an internal standard, were analyzed in the positive ion-mode by electrospray ionization and quantified by monitoring the transition at m/z 555.2â245.2 for IDP-73152 and 563.3â253.1 for the internal standard, respectively. The lower and upper limit of the assay was determined to be 5 and 10000ng/ml, respectively, with an acceptable linearity (R>0.999) in the response-concentration relationship. Validation parameters, including accuracy, precision, dilution, recovery, matrix effect and stability were found to be within the acceptable ranges recommended by the assay validation guidelines of the United States FDA. The method was successfully applied to the quantification of IDP-73152 in plasma from mice/rats that had received a single oral administration of 80mg/kg IDP-73152, in the form of the mesylate salt. These findings suggest that the validated assay can be used in preclinical and clinical pharmacokinetic studies of IDP-73152.
Assuntos
Antibacterianos/análise , Animais , Cromatografia Líquida de Alta Pressão , Humanos , Inosina Difosfato , Camundongos , Ratos , Espectrometria de Massas em TandemRESUMO
The therapeutic effect of oral administration of Lactobacillus rhamnosus IDCC 3201 tyndallizate (RHT3201) on atopic dermatitis (AD)-like skin lesions in NC/Nga mice were investigated. After induction of dermatitis in NC/Nga mice with house-dust mite extract, each group was fed RHT3201 with 1 × 10(8) , 1 × 10(9) , or 1 × 10(10) cells orally once a day for 8 weeks. Dermatitis scores and frequency of scratching were improved by oral feeding with RHT3201. In contrast to the control group, RHT3201-fed mice showed significantly down-regulated mast cell numbers and serum immunoglobulin E (IgE) concentrations had significantly less IL4 in their axillary lymph node cells. The therapeutic effect of RHT3201 was found to be dose-dependent. These findings indicate that RHT3201 has potential for treating AD.
Assuntos
Dermatite Atópica/imunologia , Imunoglobulina E/imunologia , Lacticaseibacillus rhamnosus/imunologia , Probióticos/administração & dosagem , Administração Oral , Animais , Biópsia , Citocinas/sangue , Citocinas/metabolismo , Dermatite Atópica/diagnóstico , Dermatite Atópica/terapia , Modelos Animais de Doenças , Feminino , Imunoglobulina E/sangue , Imunoterapia , Lacticaseibacillus rhamnosus/ultraestrutura , Linfonodos/imunologia , Linfonodos/metabolismo , Camundongos , FenótipoRESUMO
We have previously reported amidopiperidine derivatives as a novel peptide deformylase (PDF) inhibitor and evaluated its antibacterial activity against Gram-positive bacteria, but poor pharmacokinetic profiles have resulted in low efficacy in in vivo mouse models. In order to overcome these weaknesses, we newly synthesized aminopiperidine derivatives with remarkable antimicrobial properties and oral bioavailability, and also identified their in vivo efficacy against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE) and penicillin-resistant Streptococcus pneumoniae (PRSP).
Assuntos
Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Piperidinas/farmacologia , Administração Oral , Amidoidrolases/antagonistas & inibidores , Amidoidrolases/metabolismo , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Bactérias Gram-Positivas/enzimologia , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piperidinas/administração & dosagem , Piperidinas/química , Relação Estrutura-AtividadeRESUMO
A herd of Berkshire pigs was established in 2003 and subjected to selection without introduction of any genetic resources until 2007. The complete pedigree, including 410 boars and 916 sows, as well as the records from 5,845 pigs and 822 litters were used to investigate the results obtained from the selections. The index of selection for breeding values included days to 90 kg (D90kg), backfat thickness (BF) and number of piglets born alive (NBA). The average inbreeding coefficients of pigs were found to be 0.023, 0.008, 0.013, 0.025, 0.026, and 0.005 from 2003 to 2007, respectively. The genetic gains per year were 12.1 g, -0.04 mm, -3.13 days, and 0.181 head for average daily gain (ADG), BF, D90kg, and NBA, respectively. Breeding values of ADG, BF and D90kg were not significantly correlated with inbreeding coefficients of individuals, except for NBA (-0.21). The response per additional 1% of inbreeding was 0.0278 head reduction in NBA. The annual increase of inbreeding was 0.23% and the annual decrease in NBA due to inbreeding was 0.0064 head. This magnitude could be disregarded when compared with the annual gain in NBA (0.181 head). These results suggest that inbreeding and inbreeding depression on ordinary farms can be controlled with a proper breeding scheme and that breeding programs are economical and safe relative to the risks associated with importation of pigs.
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Hanwoo (Korean cattle) is the native, taurine type of cattle breed of Korea and its history as a draft animal dates back to 5000 Years. In earlier times Hanwoo was used extensively for farming, transportation. Over the period of time, Hanwoo has changed to be meat type cattle. Full-scale production of Hanwoo as meat-type cattle has occurred since 1960s with the rapid growth of the Korean economy. Hanwoo is one of the most economically important species in Korea as it is a significant source of nutrition to the Korean people. Hanwoo beef is the most cherished food of Korea. One of the main goals of researchers is to increase the meat quality, quantity and taste of the beef. In this review we describe the origin, domestication of Hanwoo cattle and breeding program initiated from 1980's. Moreover the advent of technological advancement had provided us a platform to perform genome wide selection on economic traits and its implementation into traditional breeding programs.
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Differentially regulated proteins within porcine somatic cell nuclear transfer (SCNT)-derived conceptuses were compared with conceptuses that were derived from natural matings on day 14 of pregnancy. Proteins that were expressed prominently on day 14 were identified in SCNT-derived conceptuses using 2-D PAGE and MALDI-TOF MS. Sixty eight proteins were identified as being differentially regulated in the SCNT-derived conceptuses. Among these, 62 were down-regulated whereas the other six proteins were up-regulated. Glycolytic proteins, such as pyruvate dehydrogenase, malate dehydrogenase and lactate dehydrogenase, were down-regulated in the SCNT-derived conceptuses whereas apoptosis-related genes as annexin V, Hsp60, and lamin A were up-regulated. Thus, apoptosis-related genes are expressed at significantly higher levels in the SCNT-derived conceptuses than in the control conceptuses, whereas metabolism-related genes are significantly reduced.
Assuntos
Animais Geneticamente Modificados/metabolismo , Embrião de Mamíferos/metabolismo , Técnicas de Transferência Nuclear , Proteoma/metabolismo , Proteômica/métodos , Análise de Variância , Animais , Animais Geneticamente Modificados/genética , Eletroforese em Gel Bidimensional , Embrião de Mamíferos/química , Embrião de Mamíferos/patologia , Feminino , Proteoma/análise , Proteoma/química , Proteoma/genética , Suínos/genética , Suínos/metabolismoRESUMO
Tobacco-specific nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N-nitrosonicotine (NNN) are potent carcinogens believed to contribute to the development of lung tumors in smokers. NNK and NNN are metabolized to DNA-reactive species that form a range of nucleobase adducts, including bulky O(6)-[4-oxo-4-(3-pyridyl)but-1-yl]deoxyguanosine (O(6)-POB-dG) lesions. If not repaired, O(6)-POB-dG adducts induce large numbers of G â A and G â T mutations. Previous studies have shown that O(6)-POB-dG can be directly repaired by O(6)-alkylguanine-DNA alkyltransferase (AGT), which transfers the pyridyloxobutyl group from O(6)-alkylguanines in DNA to an active site cysteine residue within the protein. In the present study, we investigated the influence of DNA sequence context and endogenous cytosine methylation on the kinetics of AGT-dependent repair of O(6)-POB-dG in duplex DNA. Synthetic oligodeoxynucleotide duplexes containing site-specific O(6)-POB-dG adducts within K-ras and p53 gene-derived DNA sequences were incubated with recombinant human AGT protein, and the kinetics of POB group transfer was monitored by isotope dilution HPLC-ESI(+)-MS/MS analysis of O(6)-POB-dG remaining in DNA over time. We found that the second-order rates of AGT-mediated repair were influenced by DNA sequence context (10-fold differences) but were only weakly affected by the methylation status of neighboring cytosines. Overall, AGT-mediated repair of O(6)-POB-dG was 2-7 times slower than that of O(6)-Me-dG adducts. To evaluate the contribution of AGT to O(6)-POB-dG repair in human lung, normal human bronchial epithelial cells (HBEC) were treated with model pyridyloxobutylating agent, and O(6)-POB-dG adduct repair over time was monitored by HPLC-ESI(+)-MS/MS. We found that HBEC cells were capable of removing O(6)-POB-dG lesions, and the repair rates were significantly reduced in the presence of an AGT inhibitor (O(6)-benzylguanine). Taken together, our results suggest that AGT plays an important role in protecting human lung against tobacco nitrosamine-mediated DNA damage and that inefficient AGT repair of O(6)-POB-dG at a specific sequences contributes to mutational spectra observed in smoking-induced lung cancer.
Assuntos
Adutos de DNA/química , Desoxiguanosina/análogos & derivados , O(6)-Metilguanina-DNA Metiltransferase/química , Piridinas/química , Sequência de Bases , Brônquios/citologia , Carcinógenos/química , Carcinógenos/farmacologia , Células Cultivadas , Adutos de DNA/metabolismo , Metilação de DNA , Reparo do DNA , Desoxiguanosina/química , Desoxiguanosina/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/enzimologia , Guanina/análogos & derivados , Humanos , Cinética , Nitrosaminas/química , Nitrosaminas/farmacologia , O(6)-Metilguanina-DNA Metiltransferase/antagonistas & inibidores , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , Polinucleotídeos/química , Ligação Proteica , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Piridinas/metabolismo , Mucosa Respiratória/enzimologia , Temperatura de Transição , Proteínas ras/genéticaRESUMO
Design, synthesis and biological evaluation of the imidazopyridine analogs as novel GSK3ß inhibitors for treatment of type 2 diabetes mellitus are described. Most of the analogs exhibited excellent inhibitory activities (IC50<44 nM) against glycogen synthase kinase 3ß (GSK3ß). The structure-activity relationship (SAR) of the imidazopyridine analogs and the binding mode of analog 23 in the catalytic domain of GSK3ß, based on our X-ray crystallography study, are described. In particular, analog 28, which was selected as a potential drug candidate for treatment of type 2 diabetes mellitus, exhibited excellent GSK3ß inhibition, pharmacokinetic profiles and blood glucose lowering effect in mouse.
Assuntos
Aminopiridinas/síntese química , Desenho de Fármacos , Hipoglicemiantes/síntese química , Imidazóis/química , Imidazóis/síntese química , Piridinas/química , Administração Oral , Aminopiridinas/farmacocinética , Aminopiridinas/uso terapêutico , Animais , Sítios de Ligação , Glicemia/análise , Cristalografia por Raios X , Diabetes Mellitus Experimental/tratamento farmacológico , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/uso terapêutico , Imidazóis/farmacocinética , Imidazóis/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos ICR , Microssomos/metabolismo , Estrutura Terciária de Proteína , Piridinas/farmacocinética , Piridinas/uso terapêutico , Relação Estrutura-AtividadeRESUMO
We investigated phenotypic differences in Hanwoo cattle cloned from somatic cells of a single adult. Ten genetically identical Hanwoo were generated by somatic cell nuclear transfer from a single adult. Weights at birth, growing pattern, horn and noseprint patterns were characterized to investigate phenotypic differences. The weights of clones at 6 and 12 months were slightly heavier than that of the donor. A horn pattern analysis revealed that seven clones had exactly the same horn pattern as the donor cow, whereas three were different. Although similarities such as general appearance can often be used to identify individual cloned animals, no study has characterized noseprint patterns for this end. A noseprint pattern analysis of all surviving clones showed that all eight animals had distinct noseprints. Four were similar to the donor, and the remaining four had more secondary-like characteristics.
Assuntos
Clonagem de Organismos , Técnicas de Transferência Nuclear , Fenótipo , Animais , Bovinos , Coreia (Geográfico)RESUMO
Granulocyte colony-stimulating factor (G-CSF) is a cytokine secreted by stromal cells and plays a role in the differentiation of bone marrow stem cells and proliferation of neutrophils. Therefore, G-CSF is widely used to reduce the risk of serious infection in immunocompromised patients; however, its use in such patients is limited because of its non-persistent biological activity. We created an N-linked glycosylated form of this cytokine, hG-CSF (Phe140Asn), to assess its biological activity in the promyelocyte cell line HL60. Enhanced biological effects were identified by analyzing the JAK2/STAT3/survivin pathway in HL60 cells. In addition, mutant hG-CSF (Phe140Asn) was observed to have enhanced chemoattractant effects and improved differentiation efficiency in HL60 cells. These results suggest that the addition of N-linked glycosylation was successful in improving the biological activity of hG-CSF. Furthermore, the mutated product appears to be a feasible therapy for patients with neutropenia.