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1.
Biochemistry ; 63(5): 660-670, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38385972

RESUMO

Bacterial cells tightly regulate the intracellular concentrations of essential transition metal ions by deploying a panel of metal-regulated transcriptional repressors and activators that bind to operator-promoter regions upstream of regulated genes. Like other zinc uptake regulator (Zur) proteins, Acinetobacter baumannii Zur represses transcription of its regulon when ZnII is replete and binds more weakly to DNA when ZnII is limiting. Previous studies established that Zur proteins are homodimeric and harbor at least two metal sites per protomer or four per dimer. CdII X-ray absorption spectroscopy (XAS) of the Cd2Zn2 AbZur metalloderivative with CdII bound to the allosteric sites reveals a S(N/O)3 first coordination shell. Site-directed mutagenesis suggests that H89 and C100 from the N-terminal DNA binding domain and H107 and E122 from the C-terminal dimerization domain comprise the regulatory metal site. KZn for this allosteric site is 6.0 (±2.2) × 1012 M-1 with a functional "division of labor" among the four metal ligands. N-terminal domain ligands H89 and C100 contribute far more to KZn than H107 and E122, while C100S AbZur uniquely fails to bind to DNA tightly as measured by an in vitro transcription assay. The heterotropic allosteric coupling free energy, ΔGc, is negative, consistent with a higher KZn for the AbZur-DNA complex and defining a bioavailable ZnII set-point of ≈6 × 10-14 M. Small-angle X-ray scattering (SAXS) experiments reveal that only the wild-type Zn homodimer undergoes allosteric switching, while the C100S AbZur fails to switch. These data collectively suggest that switching to a high affinity DNA-binding conformation involves a rotation/translation of one protomer relative to the other in a way that is dependent on the integrity of C100. We place these findings in the context of other Zur proteins and Fur family repressors more broadly.


Assuntos
Acinetobacter baumannii , Isoquinolinas , Sulfonamidas , Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Proteínas de Bactérias/química , Sítios de Ligação , Cádmio , Subunidades Proteicas , Espalhamento a Baixo Ângulo , Zinco/metabolismo , Difração de Raios X , Proteínas Repressoras/metabolismo , Metais , DNA/metabolismo
2.
Chin J Integr Med ; 21(7): 500-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25672502

RESUMO

OBJECTIVES: Lao Juan (LJ, ) is a syndrome described in Chinese medicine (CM) that manifests with fatigue, fever, spontaneous sweating, indigestion, work-induced pain, weakness of the limbs, and shortness of breath. The present study was conducted to examine the reliability and validity of a Lao Juan Questionnaire (LJQ). METHODS: A total of 151 outpatients and 73 normal subjects were asked to complete the LJQ. Seventy-three normal subjects were additionally asked to complete the Chalder Fatigue Scale (CFS). Twelve clinicians determined whether the 151 outpatients exhibited LJ or not. The internal consistency and construct validity for the LJQ were estimated using data from the outpatient subjects. The CFS data were used to examine the concurrent validity of the LJQ. Total LJQ scores and the clinicians᾿diagnoses of the outpatients were used to perform receiver operating characteristics (ROC) curve analyses and to define an optimum cut-off score for the LJQ. RESULTS: The 19-item LJQ had satisfactory internal consistency (α=0.828) and concurrent validity, with significant correlations between the LJQ and the CFS subscales. In the test of construct validity using principal component analysis, a total of six factors were extracted, and the overall variance explained by all factors was 59.5%. In ROC curve analyses, the sensitivity, specificity, and area under the curve were 76.0%, 59.2%, and 0.709, respectively. The optimum cut-off score was defined as six points. CONCLUSIONS: Our results suggest that the LJQ is a reliable and valid instrument for evaluating LJ.


Assuntos
Inquéritos e Questionários , Adulto , Fadiga/diagnóstico , Feminino , Humanos , Masculino , Projetos Piloto , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
3.
Biosci Biotechnol Biochem ; 78(2): 279-87, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25036682

RESUMO

Theasaponin E1 (TSE1) has been suggested to have higher biological activity than other saponins present in tea seed. Saponins have recently been considered as a potential chemotherapeutic agent for treating cancer. We examined the anti-angiogenic and anti-obesity properties of TSE1 contributing to anti-cancer efficacy. Treating with a 10 µg/mL concentration of TSE1 completely inhibited tube formation in human umbilical vein endothelial cells (HUVECs). TSE1 showed toxicity toward cancer cells and inhibited in vivo growth of the tumor. The vascular endothelial growth factor (VEGF) receptor complex was suppressed, leading to the inhibition of protein kinase B (Akt) expression and down-regulation of nuclear factor-kappa B (NF-kB) activation. The differentiating 3T3-L1 cells treated with TSE1 had decreased lipid droplet formation measured by Oil Red O staining. Reduced weight was measured in mice fed with a TSE1 plus high-fat diet. The results taken together, and particularly the NF-kB inhibition, suggest that TSE1 may have multi-target action for treating cancer as a novel chemotherapeutic agent.


Assuntos
Inibidores da Angiogênese/farmacologia , Fármacos Antiobesidade/farmacologia , Antineoplásicos/farmacologia , Ácido Oleanólico/análogos & derivados , Saponinas/farmacologia , Adipogenia/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Ácido Oleanólico/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Immunopharmacol Immunotoxicol ; 36(3): 202-10, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24754510

RESUMO

The anti-cancer activity of saponins and phenolic compounds present in green tea was previously reported. However, the immunomodulatory and adjuvanticity activity of tea saponin has never been studied. In this study, we investigated the immunomodulatory effect of tea saponin in T-lymphocytes and EL4 cells via regulation of cytokine response and mitogen-activated protein kinases (MAPK) signaling pathway. Quantitative analysis of mRNA expression level of cytokines were performed by reverse transcription polymerase chain reaction following stimulation with tea saponin, ovalbumin (OVA) alone or tea saponin in combination with OVA. Tea saponin inhibited the proliferation of EL4 cells measured in a dose-dependent manner. No cytotoxicity effect of tea saponin was detected in T-lymphocytes; rather, tea saponin enhanced the proliferation of T-lymphocytes. Tea saponin with OVA increased the expression of interleukin (IL)-1, IL-2, IL-12, interferon-γ and tumor necrosis factor (TNF)-α and decreased the expression level of IL-10 and IL-8 in T-lymphocytes. Furthermore, tea saponin, in the presence of OVA, downregulated the MAPK signaling pathway via inhibition of IL-4, IL-8 and nuclear factor kappaB (NF-κB) in EL4 cells. Th1 cytokines enhancer and Th2 cytokines and NF-κB inhibitor, tea saponin can markedly inhibit the proliferation and invasiveness of T-lymphoma (EL4) cells, possibly due to TNF-α- and NF-κB-mediated regulation of MAPK signaling pathway.


Assuntos
Antineoplásicos/farmacologia , Fatores Imunológicos/farmacologia , Linfoma de Células T/imunologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Saponinas/farmacologia , Linfócitos T/efeitos dos fármacos , Chá/química , Animais , Hemólise/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Linfócitos T/imunologia , Células Th1/imunologia , Células Th2/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia
5.
J Altern Complement Med ; 17(9): 851-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21834661

RESUMO

OBJECTIVES: The present study was conducted to examine the reliability and validity of a Phlegm Pattern Questionnaire (PPQ) that was developed within the context of Traditional Chinese Medicine. METHODS: A total of 292 normal subjects and 61 inpatients were asked to complete the PPQ. Among the 292 normal subjects, 73 college students were additionally asked to complete the Profile of Mood States (POMS) and the Chalder Fatigue Scale (CFS). Three (3) clinicians determined whether the 61 inpatients exhibited the Phlegm Pattern (PP). The authors estimated the internal consistency and construct validity for the PPQ using data from the normal and inpatient subjects. The POMS and CFS data were used to evaluate the concurrent validity of the PPQ. PPQ data and the clinicians' diagnoses of the inpatient subjects were used to estimate the sensitivity and specificity and to define the optimum cut-off point of the PPQ. RESULTS: The PPQ had satisfactory internal consistency (α=0.902 in normal subjects, α=0.919 in inpatient subjects) and concurrent validity, with significant correlations between the total score of the PPQ and all of the POMS and CFS subscales. In a test of construct validity using principal component analysis, a total of six factors were extracted, and the overall variance explained by all factors was 58.9%. In the test of discriminant validity using receiver operating characteristic curve analysis, the sensitivity, specificity, and area under the curve were 83.78%, 83.33%, and 0.860, respectively. The optimum cut-off level was defined as five points. CONCLUSIONS: These results suggest that the PPQ is a reliable and valid self-rating instrument for estimating the severity of PP.


Assuntos
Diagnóstico Diferencial , Medicina Tradicional Chinesa/métodos , Escarro , Inquéritos e Questionários/normas , Adulto , Afeto , Idoso , Fadiga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Artigo em Inglês | MEDLINE | ID: mdl-22254483

RESUMO

The pulmonary function test (PFT) is a widely used test in patients or for those who are at risk of respiratory dysfunction. In this study, we aimed to develop a more convenient system, namely, the impedance pulmonary function measurement system (IPFS), for overcoming the restrictions posed by the prevalent spirometric PFT. IPFS employs tetra polar electrodes that can measure pulmonary function using the subjects' hands alone. The impedance measured by IPFS extracts AC values of pulmonary impedance from DC values of body impedance in respiration. This system yields changes in the impedance of volume and flow. In order to verify IPFS, we compared the continuous waveforms obtained from the PFT module and developed IPFS using Pearson linear correlation coefficients (p < 0.01) for volume and flow. Further, we evaluated the potential application of IPFS for detecting pulmonary functions such as volume (FEV(1)/FVC Ratio) and flow (PEF), and compared the measured parameters between IPFS and spirometric PFT. Our results demonstrate that the measurements obtained using IPFS reflect pulmonary function parameters.


Assuntos
Algoritmos , Diagnóstico por Computador/métodos , Medidas de Volume Pulmonar/métodos , Pletismografia de Impedância/métodos , Troca Gasosa Pulmonar , Testes de Função Respiratória/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Sci Total Environ ; 408(6): 1295-307, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19906407

RESUMO

The concentrations of total gaseous mercury (TGM) and relevant environmental parameters were measured at a remote area on Jeju Island, Korea from May 2006 to May 2007. The hourly mean concentration of Hg for the entire study period was 3.85+/-1.68ng m(-3) (range of 0.10-17.9: n=7450). The temporal patterns of Hg at the island site were characterized by the relative dominance in spring/fall over summer/winter and in daytime over nighttime. The possible impact of Asian dust (AD) on Hg distribution was examined by assessing its relationship with PM(10) data. Because of a strong inverse log-log correlation between Hg and PM(10) levels (above 200microg m(-3)), a direct relationship between the two parameters is difficult to account for. However, the analysis of air mass movement patterns confirmed that the Hg levels on Jeju Island were affected most by the combined effects of major source processes in the surrounding areas: industrial and AD (China), industrial (Korea), and volcanic activity (Japan).


Assuntos
Poluentes Atmosféricos/análise , Atmosfera/química , Mercúrio/análise , Material Particulado/análise , Movimentos do Ar , Monitoramento Ambiental , Cinética , Coreia (Geográfico) , Estações do Ano
8.
J Microbiol Biotechnol ; 17(6): 979-84, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18050916

RESUMO

The physicochemical properties of the exopolysaccharide (EPS) produced by marine bacterium Zoogloea sp. KCCM10036 were investigated. Two types of isolated EPSs were shown to have average relative molecular masses (Mr) of 4.07 x 10(6) of CBP (cell-bound polysaccharide) and 3.43 x 10(6) of WSP (water-soluble polysaccharide), respectively. When the CBP was utilized as an emulsifier, it stabilized the emulsion for up to 148 h. Compared with other commercially available hydrocolloids such as xanthan gum, the Tween series, and Triton, the CBP showed much better emulsifying capability on a water-in-oil system. Phase separation occurred in the Tween series after 24 h, whereas the emulsion was better stabilized by the CBP. The CBP thus has potential as an emulsifying agent in commercial emulsions. The flocculating activity was also greatest at 0.01% (w/v) and decreased at higher concentrations than the optimized concentration of the WSP and CBP. The results also showed that both types of exopolysaccharides from Zoogloea sp. had excellent flocculating activity.


Assuntos
Polissacarídeos Bacterianos/química , Microbiologia da Água , Zoogloea/metabolismo , Emulsões , Floculação , Peso Molecular
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