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1.
Circ Res ; 135(2): 301-313, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38860363

RESUMO

BACKGROUND: The tumor suppressor and proapoptotic transcription factor P53 is induced (and activated) in several forms of heart failure, including cardiotoxicity and dilated cardiomyopathy; however, the precise mechanism that coordinates its induction with accessibility to its transcriptional promoter sites remains unresolved, especially in the setting of mature terminally differentiated (nonreplicative) cardiomyocytes. METHODS: Male and female control or TRIM35 (tripartite motif containing 35) overexpression adolescent (aged 1-3 months) and adult (aged 4-6 months) transgenic mice were used for all in vivo experiments. Primary adolescent or adult mouse cardiomyocytes were isolated from control or TRIM35 overexpression transgenic mice for all in vitro experiments. Adenovirus or small-interfering RNA was used for all molecular experiments to overexpress or knockdown, respectively, target genes in primary mouse cardiomyocytes. Patient dilated cardiomyopathy or nonfailing left ventricle samples were used for translational and mechanistic insight. Chromatin immunoprecipitation and DNA sequencing or quantitative real-time polymerase chain reaction (qPCR) was used to assess P53 binding to its transcriptional promoter targets, and RNA sequencing was used to identify disease-specific signaling pathways. RESULTS: Here, we show that E3-ubiquitin ligase TRIM35 can directly monoubiquitinate lysine-120 (K120) on histone 2B in postnatal mature cardiomyocytes. This epigenetic modification was sufficient to promote chromatin remodeling, accessibility of P53 to its transcriptional promoter targets, and elongation of its transcribed mRNA. We found that increased P53 transcriptional activity (in cardiomyocyte-specific Trim35 overexpression transgenic mice) was sufficient to initiate heart failure and these molecular findings were recapitulated in nonischemic human LV dilated cardiomyopathy samples. CONCLUSIONS: These findings suggest that TRIM35 and the K120Ub-histone 2B epigenetic modification are molecular features of cardiomyocytes that can collectively predict dilated cardiomyopathy pathogenesis.


Assuntos
Insuficiência Cardíaca , Histonas , Camundongos Transgênicos , Miócitos Cardíacos , Proteína Supressora de Tumor p53 , Ubiquitinação , Animais , Miócitos Cardíacos/metabolismo , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Humanos , Masculino , Camundongos , Feminino , Histonas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Células Cultivadas , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/patologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Regiões Promotoras Genéticas , Camundongos Endogâmicos C57BL
2.
Bioorg Med Chem Lett ; 101: 129656, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38355061

RESUMO

To discover mode-selective TRPV1 antagonists as thermoneutral drug candidates, the previous potent antagonist benzopyridone 2 was optimized based on the pharmacophore A- and C-regions. The structure activity relationship was investigated systematically by modifying the A-region by incorporating a polar side chain on the pyridone and then by changing the C-region with a variety of substituted pyridine and pyrazole moieties. The 3-t-butyl and 3-(1-methylcyclopropyl) pyrazole C-region analogs provided high potency as well as mode-selectivity. Among them, 51 and 54 displayed potent and capsaicin-selective antagonism with IC50 = 2.85 and 3.27 nM to capsaicin activation and 28.5 and 31.5 % inhibition at 3 µM concentration toward proton activation, respectively. The molecular modeling study of 51 with our homology model indicated that the hydroxyethyl side chain in the A-region interacted with Arg557 and Glu570, the urea B-region engaged in hydrogen bonding with Tyr511 and Thr550, respectively, and the pyrazole C-region made two hydrophobic interactions with the receptor. Optimization of antagonist 2, which has full antagonism for activators of all modes, lead to mode-selective antagonists 51 and 54. These observations will provide insight into the future development of clinical TRPV1 antagonists without target-based side effects.


Assuntos
Capsaicina , Ureia , Ureia/química , Capsaicina/farmacologia , Relação Estrutura-Atividade , Modelos Moleculares , Pirazóis/farmacologia , Canais de Cátion TRPV
3.
Bioorg Med Chem Lett ; 106: 129735, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38588785

RESUMO

A series of 1,4-benzoxazin-3-one analogs were investigated to discover mode-selective TRPV1 antagonists, since such antagonists are predicted to minimize target-based adverse effects. Using the high-affinity antagonist 2 as the lead structure, the structure activity relationship was studied by modifying the A-region through incorporation of a polar side chain on the benzoxazine and then by changing the C-region with a variety of substituted pyridine, pyrazole and thiazole moieties. The t-butyl pyrazole and thiazole C-region analogs provided high potency as well as mode-selectivity. Among them, antagonist 36 displayed potent and capsaicin-selective antagonism with IC50 = 2.31 nM for blocking capsaicin activation and only 47.5 % inhibition at 3 µM concentration toward proton activation, indicating that more than a 1000-fold higher concentration of 36 was required to inhibit proton activation than was required to inhibit capsaicin activation. The molecular modeling study of 36 with our homology model indicated that two π-π interactions with the Tyr511 and Phe591 residues by the A- and C-region and hydrogen bonding with the Thr550 residue by the B-region were critical for maintaining balanced and stable binding. Systemic optimization of antagonist 2, which has high-affinity but full antagonism for activators of all modes, led to the mode-selective antagonist 36 which represents a promising step in the development of clinical TRPV1 antagonists minimizing side effects such as hyperthermia and impaired heat sensation.


Assuntos
Benzoxazinas , Canais de Cátion TRPV , Ureia , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/metabolismo , Relação Estrutura-Atividade , Benzoxazinas/química , Benzoxazinas/farmacologia , Benzoxazinas/síntese química , Ureia/análogos & derivados , Ureia/química , Ureia/farmacologia , Ureia/síntese química , Humanos , Estrutura Molecular , Animais , Capsaicina/farmacologia , Capsaicina/química , Descoberta de Drogas , Relação Dose-Resposta a Droga
4.
Cancer ; 129(18): 2864-2870, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37424308

RESUMO

BACKGROUND: Indigenous Peoples have higher morbidity rates and lower life expectancies than non-Indigenous Canadians. Identification of disparities between Indigenous and non-Indigenous men regarding prostate cancer (PCa) screening, diagnoses, management, and outcomes was sought. METHODS: An observational cohort of men diagnosed with PCa between June 2014 and October 2022 was studied. Men were prospectively enrolled in the province-wide Alberta Prostate Cancer Research Initiative. The primary outcomes were tumor characteristics (stage, grade, and prostate-specific antigen [PSA]) at diagnosis. Secondary outcomes were PSA testing rates, time from diagnosis to treatment, treatment modality, and metastasis-free, cancer-specific, and overall survivals. RESULTS: Examination of 1,444,974 men for whom aggregate PSA testing data were available was performed. Men in Indigenous communities were less likely to have PSA testing performed than men outside of Indigenous communities (32 vs. 46 PSA tests per 100 men [aged 50-70 years] within 1 year; p < .001). Among 6049 men diagnosed with PCa, Indigenous men had higher risk disease characteristics: a higher proportion of Indigenous men had PSA ≥ 10 ng/mL (48% vs. 30%; p < .01), TNM stage ≥ T2 (65% vs. 47%; p < .01), and Gleason grade group ≥ 2 (79% vs. 64%; p < .01) compared to non-Indigenous men. With a median follow-up of 40 months (interquartile range, 25-65 months), Indigenous men were at higher risk of developing PCa metastases (hazard ratio, 2.3; 95% CI, 1.2-4.2; p < .01) than non-Indigenous men. CONCLUSIONS: Despite receiving care in a universal health care system, Indigenous men were less likely to receive PSA testing and more likely to be diagnosed with aggressive tumors and develop PCa metastases than non-Indigenous men.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Neoplasias da Próstata/patologia , Antígeno Prostático Específico , Detecção Precoce de Câncer , Assistência de Saúde Universal , Canadá/epidemiologia
5.
Small ; 19(7): e2206407, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36464629

RESUMO

Seeking highly-efficient, non-pollutant, and chemically robust photocatalysts for visible-light-driven ammonia production still remained challenging, especially in pure water. The key bottle-necks closely correlate to the nitrogen activation, water oxidization, and hydrogen evolution reaction (HER) processes. In this study, a novel Bi decorated imine-linked COF-TaTp (Bi/COF-TaTp) through N-Bi-O coordination is reasonably designed to achieve a boosting solar-to-ammonia conversion of 61 µmol-1  g-1  h-1 in the sacrificial-free system. On basis of serial characterizations and DFT calculations, the incorporated Bi is conducive to the acceleration of charge carriers transfer and N2 activation through the donation and back-donation mode. The N2 adsorption energy of 5% Bi/COF-TaTp is calculated to be -0.19 eV in comparison with -0.09 eV of the pure COF-TaTp and the electron exchange between N2 and the modified catalyst is much more intensive. Moreover, the accompanied hydrogen production process is effectively inhibited by Bi modification, demonstrated by the higher energy barrier for HER over Bi/COF-TaTp (2.62 eV) than the pure COF-TaTp (2.31 eV) when using H binding free energy (ΔGH* ) as a descriptor. This work supplies novel insights for the design of photocatalysts for N2 reduction and intensifies the understanding of N2 adsorption and activation over covalent organic frameworks-based materials.

6.
Bioorg Med Chem Lett ; 91: 129353, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37271378

RESUMO

The natural products neorautenol and shinpterocarpin and their structural analogs were investigated as novel anticancer agents. Twenty-four analogs, including analogs containing a polar chain and simplified analogs, were synthesized efficiently by a modified method from previous reports. The antitumor screening of synthesized compounds toward six cancer cell lines indicated that compounds 37, 42 and 43 with a dialkylaminoethyl-type side chain exhibited more promising activity than neorautenol and shinpterocarpin against lung and colon cancer lines with a range of 4-9 µM. They showed selective toxicity in normal cells.


Assuntos
Antineoplásicos , Estrutura Molecular , Relação Estrutura-Atividade , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células , Antineoplásicos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral
7.
Environ Res ; 216(Pt 1): 114541, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36228690

RESUMO

Semiconductor-based solar-driven CO2 to fuels has been widely reckoned as an ingenious approach to tackle energy crisis and climate change simultaneously. However, the high carrier recombination rate of the photocatalyst severely dampens their photocatalytic uses. Herein, an inorganic-organic heterojunction was constructed by in-situ growing a dioxin-linked covalent organic framework (COF) on the surface of rod-shaped ß-Ga2O3 for solar-driven CO2 to fuel. This novel heterojunction is featured with an ultra-narrow bandgap COF-318 (absorption edge = 760 nm), which is beneficial for fully utilizing the visible light spectrum, and a wide bandgap ß-Ga2O3 (absorption edge = 280 nm) to directional conduct electrons from COF to reduce CO2 without electron-hole recombination occurred. Results showed that the solar to fuels performance over ß-Ga2O3/COF was much superb than that of COF. The optimized Ga2O3/COF achieved an outstanding CO evolution rate of 85.8 µmol h-1·g-1 without the need of any sacrificial agent or cocatalyst, which was 15.6 times more efficient than COF. Moreover, the analyses of photoluminescence electrochemical characterizations and density functional theory (DFT) calculations revealed that the fascinate construction of ß-Ga2O3/COF heterojunction significantly favored charge separation and the directional transfer of photogenerated electrons from COF to ß-Ga2O3 followed by CO2. This study paves the way for developing effective COF-based semiconductor photocatalysts for solar-to-fuel conversion.


Assuntos
Estruturas Metalorgânicas , Catálise , Dióxido de Carbono , Fotossíntese , Semicondutores
8.
Small ; 18(52): e2205388, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36344463

RESUMO

Exploiting cost-effective, high-efficiency, and contamination-free semiconductors for photocatalytic nitrogen reduction reaction (N2 RR) is still a great challenge, especially in sacrificial-free system. On basis of the electron "acceptance-donation" concept, a boron-doped and carbon-deficient g-C3 N4 (Bx CvN) is herein developed through precise dopant and defect engineering. The optimized B15 CvN exhibisted an NH3 production rate of 135.3 µmol h-1  g-1 in pure water with nine-fold enhancement to the pristine graphitic carbon nitride (g-C3 N4 ), on account of the markedly elevated visible-light harvesting, N2 activation, and multi-directional photoinduced carriers transfer. The decorated B atoms with coexistent occupied and empty sp3 hybridized orbitals are theoretically proved to be in charge of the increase of N2 adsorption energy from -0.08 to -0.26 eV and the change in N2 adsorption model from one-way to two-way end-on pattern. Noticeably, the elaborate coordination of doped B atoms and carbon vacancies greatly facilitated the interlayer interaction and vertical charge migration of Bx CvN, which is distinctly revealed through the charge density difference calculations. The current study provides an alternative groundbreaking perspective for advancing photocatalytic N2 RR through the targeted configuration of the defect and dopant sites.

9.
Future Oncol ; 18(29): 3311-3322, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36047424

RESUMO

Background: Bladder cancer is one of the most prevalent malignancies. Due to the disadvantage of existing bladder cancer diagnostic tools, miRNAs hold promise as new diagnostic markers. Materials & methods: A total of 224 participants were involved in this three-cohort trial. A total of 15 candidate miRNAs were selected, and miRNAs with diagnostic ability were screened out with quantitative reverse transcription PCR. Diagnostic capability was ascertained by the receiver operating characteristic curve and area under the curve. Bioinformatics analysis was constructed for target gene prediction and functional annotation. Results: Six candidate miRNAs showed significantly different expression between bladder cancer patients and normal controls, and the final diagnostic panel comprised miR-181b-5p, miR-183-5p, miR-199-5p and miR-221-3p. Conclusion: This four-miRNA panel could represent a stable biomarker for bladder cancer diagnosis.


Bladder cancer is one of the most prevalent malignancies. Due to the disadvantage of existing bladder cancer diagnostic tools, miRNAs hold promise as new diagnostic markers. After an experiment composed of 224 participants, the authors screened out six candidate miRNAs that may contribute to diagnosing bladder cancer. The authors also repeatedly verified the reliability of candidate miRNAs. Finally, a combination of multiple miRNAs, consisting of miR-181b-5p, miR-183-5p, miR-199-5p, and miR-221-3p, was better and more reliable in predicting bladder cancer occurrence.


Assuntos
MicroRNAs , Neoplasias da Bexiga Urinária , Humanos , Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica , MicroRNAs/genética , Curva ROC , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética
10.
J Clin Lab Anal ; 36(2): e24194, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35028969

RESUMO

BACKGROUND: Nasopharyngeal carcinoma is cancer with unique epidemiological characteristics, showing obvious ethnicity, gender, and geographical prevalence. More and more evidence shows that microRNAs are stable in serum and are specific to different tumor types. Therefore, miRNA is a new non-invasive biomarker for cancer detection. METHODS: The experiment is divided into three stages, namely, the screening stage, the training stage, and the verification stage. We took 54 patients with nasopharyngeal carcinoma and 108 healthy controls as the research objects. We use the receiver-operating characteristic (ROC) curve and area under the ROC curve (AUC) to evaluate the diagnostic value of miRNA. Finally, a three-miRNA panel with high diagnostic efficiency was constructed. In addition, we conducted biological information analysis of these miRNAs to explore their functions. RESULTS: In NPC patients, the expression of five serum miRNAs (miR-29c-3p, miR-143-5p, miR-150-5p, miR-145-3p, and miR-205-5p) is significantly dysregulated. Among them, the diagnostic value of these three miRNAs (miR-29c-3p, AUC = 0.702; miR-143-5p, AUC = 0.733; and miR-205-5p, AUC = 787) is more prominent. The diagnostic panel constructed by them has a higher diagnostic value (AUC = 0.902). Through the analysis of the TCGA data set, the target gene of the three-miRNA panel may be KLF7, NRG1, SH3BGRL2, and SYNPO2. CONCLUSION: The three-miRNA panel (miR-29c-3p, miR-143-5p, and miR-205-5p) may become a novel non-invasive biological marker for nasopharyngeal cancer screening.


Assuntos
Biomarcadores Tumorais/sangue , MicroRNA Circulante/sangue , Carcinoma Nasofaríngeo/genética , Adulto , Detecção Precoce de Câncer/métodos , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/sangue , Carcinoma Nasofaríngeo/diagnóstico , Curva ROC , Sensibilidade e Especificidade
11.
Opt Express ; 29(16): 25365-25376, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34614869

RESUMO

A practical direct-view scheme for generating arbitrary high-order cylindrical vector (HCV) beams by cascading vortex half-wave plates (VHPs) is presented. The combination of odd number 2n-1 VHPs for n≥1 can realize (m2n-1-m2n-2+…+m1)-order CV beams, in which m is the order number of VHP and the corresponding subscript 2n-1 represents the arrangement number of VHPs, and the cascading of even number 2n ones can obtain (m2n-m2n-1+…+m2-m1)-order CV beams. All 1-12 order CV beams, including the high-order anti-vortex CV (ACV) beams, are generated only by selectively cascading the VHPs with m=1, 3 and 8. The polarization properties of the generated HCV beams are investigated by measuring the corresponding Stokes parameters. It is experimentally demonstrated that arbitrary HCV beams are effectively achieved by the proposed method. The order numbers of CV beams can be greatly expanded by cascading limited types of VHPs.

12.
J Clin Lab Anal ; 35(2): e23599, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33247622

RESUMO

The diagnosis of renal cell carcinoma (RCC) is often made late since there is no early symptom, which thus results in dismal patient prognosis. As a result, new biomarkers are urgently needed and efforts should be made to identify their functions in predicting RCC prognosis. microRNAs (miRNAs) are a class of small noncoding RNAs that are about 20-22 nucleotides in length, and they have been demonstrated to function as prognostic markers in numerous tumors. This study aimed to assess the role of miR-30b-5p in predicting the prognosis of RCC postoperatively. In this study, RNA was extracted from 284 formalin-fixed and paraffin-embedded kidney cancer tissue samples. After cDNA synthesis, real-time quantitative PCR (RT-qPCR) was adopted for detecting the relative miR-30b-5p level. Then, the Kaplan-Meier method, Cox regression analysis, and the receiver operating characteristic curve analysis were applied in analyzing the miR-30b-5p effect on the prognosis for patients. Our findings indicated that, following adjustment for age, gender, tumor stage, and tumor size, patients with low miR-30b-5p expression had remarkably longer overall survival. Thus, the miR-30b-5p level might be related to RCC prognosis.


Assuntos
Carcinoma de Células Renais/genética , Carcinoma de Células Renais/mortalidade , Neoplasias Renais/genética , Neoplasias Renais/mortalidade , MicroRNAs/genética , Idoso , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Regulação para Cima
13.
Environ Res ; 190: 110018, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32810495

RESUMO

Photocatalytic bacterial inactivation under visible light emerges as a new alternative to control microbial contamination by utilizing free and renewable sunlight. However, the exploration of highly effective and safe visible-light-driven (VLD) photocatalysts remains an important step toward accessing this new technology. Herein, an eco-friendly photocatalyst, namely Indium Sulfide (In2S3), was fabricated through a facile hydrothermal method for VLD photocatalytic inactivation of bacteria. The energy band gap of the as-prepared In2S3 was measured as 2.25 eV. As expected, the obtained In2S3 photocatalyst showed remarkable inactivation efficiency toward E. coli under fluorescent tubes irradiation. The photocatalytic inactivation kinetic was perfectly fitted by a mathematical model for bacteria inactivation. In addition, In2S3 exhibited high stability and could be reused. The leakage of In3+ was not significant and showed no toxic effect to the bacteria. Based on the results of scavenger study and ESR technology, the dominant reactive species causing In2S3 VLD photocatalytic bacterial inactivation were proposed as O2-, h+, H2O2 and e-, rather than OH. The SEM study suggested that the damages to the intracellular components occurred prior to the destruction of cell wall. This study provides novel application of In2S3 for VLD photocatalytic inactivation of bacteria as well as comprehensive insight into the inactivation mechanism.


Assuntos
Escherichia coli , Peróxido de Hidrogênio , Catálise , Cinética , Luz
14.
J Am Chem Soc ; 141(7): 2872-2877, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30721058

RESUMO

The first asymmetric total synthesis of the highly strained compound cerorubenic acid-III is reported. A type II intramolecular [5 + 2] cycloaddition allowed efficient and diastereoselective construction of the synthetically challenging bicyclo[4.4.1] ring system with a strained bridgehead (anti-Bredt) double bond in the final product. A unique transannular cyclization installed the vinylcyclopropane moiety with retention of the desired stereochemistry.

15.
Bioorg Med Chem Lett ; 28(17): 2945-2948, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30006066

RESUMO

We report herein the design, synthesis and antimycobacterial activity of 3,5-dinitrobenzamide derivatives containing fused ring moieties. Results reveal that many of the target compounds have considerable in vitro antitubercular activity. Especially, N-((2-(4-fluorophenyl)/N-((2-(3-fluorobenzyl)-1,2,3,4-tetrahydroisoquilin-6-yl)methyl)-3,5-dinitrobenzamides 18a and 20e exhibit potent MIC values of 0.056-0.078 µg/mL against both drug-sensitive Mycobacterium tuberculosis (MTB) H37Rv strain and two clinically isolated multidrug-resistant MTB (MDR-MTB) strains, opening a new direction for further SAR studies.


Assuntos
Antibacterianos/farmacologia , Benzamidas/farmacologia , Desenho de Fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Benzamidas/síntese química , Benzamidas/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium tuberculosis/isolamento & purificação , Relação Estrutura-Atividade
16.
Environ Sci Technol ; 51(24): 14342-14351, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29135237

RESUMO

A clear understanding of membrane aging process is essential for the optimization of chemical cleaning in membrane-based facilities. In this study, two-dimensional (2D) Fourier transformation infrared (FTIR) correlation spectroscopy (CoS) analysis was first used to decipher the sequential order of functional group changes of NaOCl-aged poly(ether sulfone)/polyvinylpyrrolidone (PES/PVP) membranes. The synchronous maps showed 12 major autopeaks in total. Based on the asynchronous maps, a similar aging sequence of membrane groups was clearly identified at three pHs (i.e., 6, 8, and 10): 1463, 1440, and 1410 (cyclic C-H structures) > 1662 (amide groups) > 1700 (succinimide groups) > 1320, 1292 (S═O asymmetric) > 1486, 1580 (aromatic structures) > 1241 (aromatic ether bands) > 1105, 1150 cm-1 (O═S═O symmetric). Among them, membrane chlorination occurred at 1241, 1410, and 1440 cm-1. Moreover, the initial degradation of PVP and the subsequent transformation of PES could be highly responsible for the increased water permeability and the enlargement of membrane pores, respectively, both leading to serious fouling with humic acid filtration. In summary, the 2D-FTIR-CoS analysis is a powerful approach to reveal the interaction mechanisms of NaOCl-membrane and could be also useful to probe the process of membrane fouling and chemical cleaning.


Assuntos
Povidona , Espectroscopia de Infravermelho com Transformada de Fourier , Éter , Éteres , Membranas Artificiais , Sulfonas
17.
Int J Vitam Nutr Res ; 87(5-6): 1-10, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27866467

RESUMO

Mushrooms are a great source of vitamin D and vitamin B2; however, the content of these vitamins in dried mushrooms has not fully been investigated. Thus, the objectives of this study were to determine the contents of vitamin D2, ergosterol, and vitamin B2 in commercially dried edible mushrooms in China and to investigate the effect of UV-C irradiation on fresh mushrooms. Among the 35 species of dried mushrooms considered for this study, the average ergosterol content was 1.98 mg/g, while the average vitamin D2 content was 16.88 µg/g. The average vitamin B2 content in dried mushrooms was 12.68 µg/g. Fresh shaggy ink caps and oyster mushrooms, when exposed to UV-C at 254 nm at a dose of 0.25 J/cm2 for 10, 30, and 60 min, showed significantly (p < 0.05) increased vitamin D2 content (229.7 and 67.0 µg/g, respectively) as compared to its fresh counterparts. The conversion of ergosterol to vitamin D2 induced by UV-C irradiation at 0.25 J/cm2 was significant (p < 0.05). In conclusion, dried commercial mushrooms have higher contents of ergosterol and vitamin D2 than fresh mushrooms. UV-C radiation can be used to increase vitamin D2 content in mushrooms.

18.
Molecules ; 22(7)2017 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-28703766

RESUMO

A series of novel 8-OMe ciprofloxacin (CPFX)-hydrazone/azole hybrids were designed, synthesized, and evaluated for their in vitro biological activities. Our results reveal that all of the hydrozone-containing hybrids (except for 7) show potency against Mycobacterium tuberculosis (MTB) H37Rv (minimum inhibitory concentration (MIC): <0.5 µM), which is better than the parent drug CPFX, and comparable to moxifloxacin and isoniazid, some of the tested Gram-positive strains (MIC: 0.06-4 µg/mL), and most Gram-negative strains (MIC: ≤0.03-4 µg/mL).


Assuntos
Ciprofloxacina/química , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antituberculosos/síntese química , Antituberculosos/química , Antituberculosos/farmacologia , Azóis/síntese química , Azóis/química , Azóis/farmacologia , Ciprofloxacina/análogos & derivados , Ciprofloxacina/síntese química , Ciprofloxacina/farmacologia , Humanos , Hidrozoários/química , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/patogenicidade , Tuberculose/microbiologia
19.
Appl Environ Microbiol ; 81(15): 5174-83, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26002903

RESUMO

The dual roles of capsular extracellular polymeric substances (EPS) in the photocatalytic inactivation of bacteria were demonstrated in a TiO2-UVA system, by comparing wild-type Escherichia coli strain BW25113 and isogenic mutants with upregulated and downregulated production of capsular EPS. In a partition system in which direct contact between bacterial cells and TiO2 particles was inhibited, an increase in the amount of EPS was associated with increased bacterial resistance to photocatalytic inactivation. In contrast, when bacterial cells were in direct contact with TiO2 particles, an increase in the amount of capsular EPS decreased cell viability during photocatalytic treatment. Taken together, these results suggest that although capsular EPS can protect bacterial cells by consuming photogenerated reactive species, it also facilitates photocatalytic inactivation of bacteria by promoting the adhesion of TiO2 particles to the cell surface. Fluorescence microscopy and scanning electron microscopy analyses further confirmed that high capsular EPS density led to more TiO2 particles attaching to cells and forming bacterium-TiO2 aggregates. Calculations of interaction energy, represented by extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) potential, suggested that the presence of capsular EPS enhances the attachment of TiO2 particles to bacterial cells via acid-base interactions. Consideration of these mechanisms is critical for understanding bacterium-nanoparticle interactions and the photocatalytic inactivation of bacteria.


Assuntos
Cápsulas Bacterianas/efeitos dos fármacos , Cápsulas Bacterianas/efeitos da radiação , Escherichia coli/efeitos dos fármacos , Escherichia coli/efeitos da radiação , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Oxidantes Fotoquímicos/toxicidade , Carga Bacteriana , Escherichia coli/citologia , Escherichia coli/fisiologia , Microscopia , Titânio/toxicidade , Raios Ultravioleta
20.
Environ Sci Technol ; 49(10): 6264-73, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25894494

RESUMO

Earth-abundant red phosphorus was found to exhibit remarkable efficiency to inactivate Escherichia coli K-12 under the full spectrum of visible light and even sunlight. The reactive oxygen species (•OH, •O2(-), H2O2), which were measured and identified to derive mainly from photogenerated electrons in the conduction band using fluorescent probes and scavengers, collectively contributed to the good performance of red phosphorus. Especially, the inactivated-membrane function enzymes were found to be associated with great loss of respiratory and ATP synthesis activity, the kinetics of which paralleled cell death and occurred much earlier than those of cytoplasmic proteins and chromosomal DNA. This indicated that the cell membrane was a vital first target for reactive oxygen species oxidation. The increased permeability of the cell membrane consequently accelerated intracellular protein carboxylation and DNA degradation to cause definite bacterial death. Microscopic analyses further confirmed the cell destruction process starting with the cell envelope and extending to the intracellular components. The red phosphorus still maintained good performance even after recycling through five reaction cycles. This work offers new insight into the exploration and use of an elemental photocatalyst for "green" environmental applications.


Assuntos
Escherichia coli K12 , Luz , Isótopos de Fósforo/farmacologia , Purificação da Água , Escherichia coli K12/efeitos dos fármacos , Escherichia coli K12/efeitos da radiação , Oxirredução , Espécies Reativas de Oxigênio , Microbiologia da Água
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