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1.
Proc Natl Acad Sci U S A ; 120(46): e2310883120, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37934818

RESUMO

Development of single-component organic phosphor attracts increasing interest due to its wide applications in optoelectronic technologies. Theoretically, activating efficient intersystem crossing (ISC) via 1(π, π*) to 3(π, π*) transitions, rather than 1(n, π*) → 3(π, π*) transitions, is an alternative access to purely organic phosphors but remains challenging. Herein, we designed and successfully synthesized the sila-8-membered ring fused biaryl benzoskeleton by transition metal catalysis, which served as a new organic phosphor with efficient 1(π, π*) to 3(π, π*) ISC. We first found that such a compound exhibits a record-long phosphorescence lifetime of 6.5 s at low temperature for single-component organic systems. Then, we developed two strategies to tune their decay channels to evolve such nonemissive molecules into bright phosphors with elongated lifetimes at room temperature: 1) Physic-based design, where quantitative analyses of electron-phonon coupling led us to reveal and hinder the major nonradiative channels, thus lighted up room temperature phosphorescence (RTP) with a lifetime of 480 ms at 298 K; 2) chemical geometry-driven molecular engineering, where a geometry-based descriptor ΔΘT1-S0/ΘS0 was developed for rational screening RTP candidates and further improved the RTP lifetime to 794 ms. This study clearly shows the power of interdiscipline among synthetic methodology, physics-based rational design, and computational modeling, which represents a paradigm for the development of an organic emitter.

2.
Ecotoxicol Environ Saf ; 278: 116400, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38718725

RESUMO

Evidence increasingly suggests molybdenum exposure at environmental levels is still associated with adverse human health, emphasizing the necessity to establish a more protective reference dose (RfD). Herein, we conducted a study measuring 15 urinary metals and 30 clinical health indicators in 2267 participants residing near chemical enterprises across 11 Chinese provinces to investigate their relationships. The kidney and cystatin-C emerged as the most sensitive organ and critical effect indicator of molybdenum exposure, respectively. Odds of cystatin-C-defined chronic kidney disease (CKD) in the highest quantile of molybdenum exposure significantly increased by 133.5% (odds ratio [OR]: 2.34, 95% CI: 1.78, 3.11) and 75.8% (OR: 1.76, 95% CI: 1.24, 2.49) before and after adjusting for urinary 14 metals, respectively. Intriguingly, cystatin-C significantly mediated 15.9-89.5% of molybdenum's impacts on liver and lung function, suggesting nephrotoxicity from molybdenum exposure may trigger hepatotoxicity and pulmonary toxicity. We derived a new RfD for molybdenum exposure (0.87 µg/kg-day) based on cystatin-C-defined estimated glomerular filtration rate by employing Bayesian Benchmark Dose modeling analysis. This RfD is significantly lower than current exposure guidance values (5-30 µg/kg-day). Remarkably, >90% of participants exceeded the new RfD, underscoring the significant health impacts of environmental molybdenum exposure on populations in industrial regions of China.


Assuntos
Molibdênio , Molibdênio/urina , Molibdênio/toxicidade , Molibdênio/análise , Humanos , China/epidemiologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Exposição Ambiental/estatística & dados numéricos , Exposição Ambiental/análise , Cistatina C , Medição de Risco , Poluentes Ambientais/urina , Poluentes Ambientais/análise , Adulto Jovem , Teorema de Bayes , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/induzido quimicamente , Idoso , Indústria Química , Rim/efeitos dos fármacos , Taxa de Filtração Glomerular/efeitos dos fármacos
3.
Ecotoxicol Environ Saf ; 274: 116203, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38479313

RESUMO

PCDD/Fs are dioxins produced by waste incineration and pose risks to human health. We aimed to detail the health risks of airborne and soil PCDD/Fs near a municipal solid-waste incinerator (MSWI) for the surrounding population and develop a new model that improves upon existing methods. Thus, we conducted field sampling and then investigated a MSWI in the Pearl River Delta (2016-2018). Our results showed that the carcinogenic and non-carcinogenic risk values of PCDD/Fs exposed to residents in nearby areas were acceptable, with hazard index (HI) values lower than 1.0 and a total carcinogenic risk lower than 1.0E-6. Notably, the results raised concerns regarding higher non-carcinogenic risks in children than in adults. Comparative analysis of the frequency accumulation diagram, accumulated probability risk, and the absolute value of error (δ) between the 95% confidence interval (CI) and the 90% CI of the Monte Carlo stochastic simulation-triangular fuzzy number (MCSS-TFN) and the MCSS model, respectively, demonstrated that the MCSS-TFN exhibited less uncertainty than the MCSS model, regardless of the health risk value of PCDD/Fs in ambient air or in soil. This observation underscores the superiority of the MCSS-TFN model over other models in assessing the health risks associated with PCDD/Fs in situations with limited data. Our new method overcomes the limited dataset size and high uncertainty in assessing the health risks of dioxin substances, providing a more comprehensive understanding of their associated health risks than MCSS models.


Assuntos
Poluentes Atmosféricos , Dioxinas , Dibenzodioxinas Policloradas , Adulto , Criança , Humanos , Resíduos Sólidos , Monitoramento Ambiental/métodos , Dibenzodioxinas Policloradas/toxicidade , Dibenzodioxinas Policloradas/análise , Dibenzofuranos , Poluentes Atmosféricos/análise , Incineração , Dioxinas/toxicidade , Medição de Risco , Dibenzofuranos Policlorados/análise , Solo
4.
Biochem Biophys Res Commun ; 658: 44-54, 2023 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-37023614

RESUMO

Some genes are delivered to cochleae by adenoviruses to restore partial hearing function. This provides promising prospects for gene therapies for hearing loss from hair cell damage. To study the adenovirus (AD)-mediated effect of the Wnt and Notch signalling pathways on hair cell regeneration in the mouse cochlea, we constructed a ß-catenin-adenovirus (ß-catenin-AD) to increase the activity of the Wnt signalling pathway and a NICD (intracellular domain of Notch1)-RNAi-adenovirus to decrease the activity of the Notch signalling pathway (NICD-RNAi-AD). Our study indicated that approximately 40% of supporting cells in the cochleae damaged by gentamicin were infected with the adenoviruses. Following the ß-catenin-AD-mediated increase in Wnt signalling pathway activity, mitotic regeneration was increased, while direct transdifferentiation was increased after the NICD-RNAi-AD-mediated decrease in Notch signalling pathway activity. The expected synergistic interaction on hair cell regeneration was not obtained after coinfection of ß-catenin-AD and NICD-RNAi-AD into the damaged cochleae, which might be due to the low cotransfection efficiency to supporting cells. Our study indicated that it may be possible to develop AD mediated gene therapies for hearing loss that act by regulating the Wnt and Notch signalling pathways.


Assuntos
Perda Auditiva , beta Catenina , Animais , Camundongos , beta Catenina/genética , beta Catenina/metabolismo , Adenoviridae/genética , Adenoviridae/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Via de Sinalização Wnt/fisiologia
5.
Environ Sci Technol ; 57(21): 7938-7949, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37202343

RESUMO

Obesity is prevalent in rural areas of China, and there are inconsistent findings regarding the association between metal(loid) exposure and the risk of obesity. Abdominal obesity (AOB), which reflects visceral fat abnormity, is a crucial factor in studying obesity-related diseases. We conducted a study measuring 20 urinary metal(loid)s, 13 health indicators, and the waist circumference (WC) in 1849 participants from 10 rural areas of China to investigate their relationships. In the single exposure models, we found that urinary chromium (Cr) was significantly associated with the odds of having AOB [adjusted odds ratio (OR) = 1.81 (95% confidence interval (CI): 1.24, 2.60)]. In the mixture exposure models, urinary Cr consistently emerged as the top contributor to AOB, while the overall effect of mixed metal(loid)s was positive toward the odds of having AOB [adjusted OR: 1.33 (95% CI: 1.00, 1.77)], as revealed from the quantile g-computation model. After adjusting for the effects of other metal(loid)s, we found that the elevation of apolipoprotein B and systolic blood pressure significantly mediated the association between urinary Cr and the odds of having AOB by 9.7 and 19.4%, respectively. Our results suggest that exposure to metal(loid)s is a key factor contributing to the prevalence of AOB and WC gain in rural areas of China.


Assuntos
Metaloides , Metais Pesados , Humanos , Obesidade Abdominal/epidemiologia , Metais/análise , Obesidade/epidemiologia , Cromo , China/epidemiologia , Gordura Abdominal/química , Medição de Risco , Monitoramento Ambiental/métodos
6.
Bull Math Biol ; 85(4): 28, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36853371

RESUMO

Hosts can activate a defensive response to clear the parasite once being infected. To explore how host survival and fecundity are affected by host-parasite coevolution for chronic parasitic diseases, in this paper, we proposed an age-structured epidemic model with infection age, in which the parasite transmission rate and parasite-induced mortality rate are structured by the infection age. By use of critical function analysis method, we obtained the existence of the host immune evolutionary singular strategy which is a continuous singular strategy (CSS). Assume that parasite-induced mortality begins at infection age [Formula: see text] and is constant v thereafter. We got that the value of the CSS, [Formula: see text], monotonically decreases with respect to infection age [Formula: see text] (see Case (I)), while it is non-monotone if the constant v positively depends on the immune trait c (see Case (II)). This non-monotonicity is verified by numerical simulations and implies that the direction of immune evolution depends on the initial value of immune trait. Besides that, we adopted two special forms of the parasite transmission rate to study the parasite's virulence evolution, by maximizing the basic reproduction ratio [Formula: see text]. The values of the convergence stable parasite's virulence evolutionary singular strategies [Formula: see text] and [Formula: see text] increase monotonically with respect to time lag L (i.e., the time lag between the onset of transmission and mortality). At the singular strategy [Formula: see text] and [Formula: see text], we further obtained the expressions of the case mortalities [Formula: see text] and how they are affected by the time lag L. Finally, we only presented some preliminary results about host and parasite coevolution dynamics, including a general condition under which the coevolutionary singular strategy [Formula: see text] is evolutionarily stable.


Assuntos
Parasitos , Animais , Virulência , Conceitos Matemáticos , Modelos Biológicos , Número Básico de Reprodução
7.
PLoS Genet ; 16(10): e1009157, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33108367

RESUMO

In rice (Oryza sativa), caryopses located on proximal secondary branches (CSBs) have smaller grain size and poorer grain filling than those located on apical primary branches (CPBs), greatly limiting grain yield. However, the molecular mechanism responsible for developmental differences between CPBs and CSBs remains elusive. In this transcriptome-wide expression study, we identified the gene Aspartic Protease 1 (OsAsp1), which reaches an earlier and higher transcriptional peak in CPBs than in CSBs after pollination. Disruption of OsAsp1 expression in the heterozygous T-DNA line asp1-1+/-eliminated developmental differences between CPBs and CSBs. OsAsp1 negatively regulated the transcriptional inhibitor of auxin biosynthesis, OsTAA1 transcriptional inhibition factor 1 (OsTIF1), to preserve indole-3-acetic acid (IAA) apical dominance in CPBs and CSBs. IAA also facilitated OsTIF1 translocation from the endoplasmic reticulum (ER) to the nucleus by releasing the interaction of OsTIF1 with OsAsp1 to regulate caryopses IAA levels via a feedback loop. IAA promoted transcription of OsAsp1 through MADS29 to maintain an OsAsp1 differential between CPBs and CSBs during pollination. Together, these findings provide a mechanistic explanation for the distributed auxin differential between CPBs and CSBs to regulate distinct caryopses development in different rice branches and potential targets for engineering yield improvement in crops.


Assuntos
Ácidos Indolacéticos/metabolismo , Proteínas Nucleares/genética , Oryza/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Ácido Aspártico Proteases/genética , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Retículo Endoplasmático/genética , Regulação da Expressão Gênica de Plantas/genética , Oryza/crescimento & desenvolvimento , Desenvolvimento Vegetal/genética , Reguladores de Crescimento de Plantas/genética , Polinização/genética
8.
J Exp Bot ; 73(1): 413-428, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34499162

RESUMO

Ethylene response factor (ERF) Group VII members generally function in regulating plant growth and development, abiotic stress responses, and plant immunity in Arabidopsis; however, the details of the regulatory mechanism by which Group VII ERFs mediate plant immune responses remain elusive. Here, we characterized one such member, ERF72, as a positive regulator that mediates resistance to the necrotrophic pathogen Botrytis cinerea. Compared with the wild-type (WT), the erf72 mutant showed lower camalexin concentration and was more susceptible to B. cinerea, while complementation of ERF72 in erf72 rescued the susceptibility phenotype. Moreover, overexpression of ERF72 in the WT promoted camalexin biosynthesis and increased resistance to B. cinerea. We identified the camalexin-biosynthesis genes PAD3 and CYP71A13 and the transcription factor WRKY33 as target genes of ERF72. We also determined that MPK3 and MPK6 phosphorylated ERF72 at Ser151 and improved its transactivation activity, resulting in increased camalexin concentration and increased resistance to B. cinerea. Thus, ERF72 acts in plant immunity to coordinate camalexin biosynthesis both directly by regulating the expression of biosynthetic genes and indirectly by targeting WRKK33.


Assuntos
Proteínas de Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Botrytis , Regulação da Expressão Gênica de Plantas , Indóis , Fosforilação , Doenças das Plantas/genética , Tiazóis
9.
Transgenic Res ; 30(6): 811-820, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34146237

RESUMO

Drought and salt are two major abiotic stresses that severely impact plant growth and development, as well as crop production. A previous study showed that OsOSCA1.4, one of eleven rice OSCAs (OsOSCAs), complements hyperosmolality-induced [Ca2+]cyt increases (OICIcyt), salt stress-induced [Ca2+]cyt increases (SICIcyt) and the associated growth phenotype in Arabidopsis osca1 (reduced hyperosmolality-induced [Ca2+]cyt increase 1). In this study, Except for OsOSCA2.3 and OsOSCA4.1, we generated independent transgenic lines overexpressing eight other OsOSCAs in the osca1 to explore their functions in osmotic Ca2+ signalling, stomatal movement, leaf water loss, and root growth in response to hyperosmolality and salt stress. Similar to OsOSCA1.4, overexpression of OsOSCA1.1 or OsOSCA2.2 in osca1 complemented OICIcyt and SICIcyt, as well as stomatal closure and root growth in response to hyperosmolality and salt stress treatments, and drought-related leaf water loss. In addition, overexpression of OsOSCA1.2, OsOSCA1.3 or OsOSCA2.1 in osca1 restored OICIcyt and SICIcyt, whereas overexpression of OsOSCA2.5 or OsOSCA3.1 did not. Moreover, osca1 overexpressing these five OsOSCAs exhibited various abiotic stress-associated growth phenotypes. However, overexpression of OsOSCA2.4 did not have any of these effects. These results indicated that multiple members of the OsOSCA family have redundant functions in osmotic sensing and diverse roles in stress adaption.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Oryza , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Secas , Regulação da Expressão Gênica de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Salino/genética , Estresse Fisiológico/genética , Água/metabolismo
10.
Angew Chem Int Ed Engl ; 59(22): 8471-8475, 2020 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-32124524

RESUMO

An enantioselective aldehyde α-alkylation/semipinacol rearrangement was achieved through organo-SOMO catalysis. The catalytically generated enamine radical cation serves as a carbon radical electrophile that can stereoselectively add to the alkene of an allylic alcohol and initiate ensuing ring-expansion of cyclopropanol or cyclobutanol. This tandem reaction enables the production of a wide range of nonracemic functionalizable α-quaternary-δ-carbonyl cycloketones in high yields and excellent enantioselectivity from simple aldehydes and allylic alcohols. As a key step, the intramolecular reaction was also successfully applied in the asymmetric total synthesis of (+)-cerapicol.

11.
Opt Express ; 27(26): 38451-38462, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878612

RESUMO

We investigate circularly polarized photoluminescence (PL) in the MoS2/MoO3 heterostructure, which was fabricated by transferring MoS2 monolayer to cover the MoO3 few layers on the SiO2/Si substrate. It is shown that the PL with the same helicity as the excitation light is dominant due to the inherent chiral optical selectivity, which allows exciting one of the valleys in MoS2 monolayer. The degree of polarization (DP), which characterizes the intensity difference of two chiral components of PL, is unequal for the right-handed and left-handed circularly polarized excitations in the MoS2/MoO3 heterostructure. This effect is different from the one in pristine MoS2. Our Raman spectra results together with ab initio calculations indicate the p-doped features of the MoS2 when it covers the MoO3 layers. Thus the possible explanation of the unequal DP is that the p-doping process generates a built-in voltage and therefore brings the difference of electron-hole overlaps between K and K' valleys. Namely the asymmetric valley polarization may be obtained in the MoS2/MoO3 heterostructure. Consequently, the circularly polarized PL caused by the electron-hole recombination at K and K' valleys manifests unequal DP for the right-handed and left-handed helix excitations. This asymmetric effect is further enhanced by decreasing the temperature in the MoS2/MoO3 heterostructure. Our investigation provides a unique platform for developing novel two-dimensional valleytronic devices.

12.
Ecotoxicol Environ Saf ; 178: 105-112, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30999178

RESUMO

Human hair, flue gas and fly ash from a municipal solid waste incinerator (MSWI) in south China were collected and analyzed for polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF). The ΣPCDD/F level in hair from male workers were higher than those from residents. The Principal Component Analysis (PCA) suggested that ΣPCDD/F in flue gas is an external source of male workers' hair ΣPCDD/F. Results of daily intake of ΣPCDD/F by inhaling flue gas suggested that the inhalation exposure of ΣPCDD/F was at a slight health risk. For the male workers directly exposed to the MSWI power plant, ΣPCDD/F levels in their hair were significantly higher than those who were non-directly exposed. Moreover, a significantly positive relationship was obtained between ΣPCDD/F levels in male workers' hair and the working time. The result of correlation analysis suggested that 1,2,3,4,6,7,8-HpCDD and OCDD could be level indicator congeners to estimate ΣPCDD/F levels. In addition, 2,3,7,8-TCDD could be applied as TEQ indicator congener to characterize the hair of MSWI male workers.


Assuntos
Dibenzofuranos Policlorados/análise , Cabelo/química , Incineração , Exposição por Inalação/análise , Exposição Ocupacional/análise , Dibenzodioxinas Policloradas/análise , China , Cinza de Carvão/análise , Humanos , Masculino , Resíduos Sólidos/análise
13.
Zhonghua Nan Ke Xue ; 25(6): 489-495, 2019 Jun.
Artigo em Zh | MEDLINE | ID: mdl-32223081

RESUMO

OBJECTIVE: To investigate the correlation between the behavioral performance and the expressions of substance P (SP) and neurokinin-1 receptor (NK-1R) in the posterior horn of the L5-S2 spinal cord in rats with chronic prostatitis (CP). METHODS: A CP model was made in 30 adult male SD rats by intraperitoneal injection of 0.5 ml dyphtheria pertussis tetanus (DPT) vaccine and mixed solution of 1 ml prostatein extract and complete adjuvant in a 1∶1 ratio, and another 10 rats were injected with the same volume of normal saline as controls. At 45 (n = 10), 60 (n = 10) and 90 days (n = 10) after modeling, the behavioral changes of the rats were observed by open-field and sucrose consumption tests, the prostatic indexes and levels of serum TNF-α, IL-1ß, IL-2 and IL-10 were obtained, and the expressions of SP and NK1-R in the L5-S2 spinal cord were determined by immunohistochemistry. RESULTS: Compared with the controls, the CP model rats showed obviously decreased horizontal and vertical movement scores and sucrose consumption, particularly in the 90 d group (P < 0.05), significantly reduced prostatic indexes in the 45 d, 60 d and 90 d groups (all P < 0.05), even lower in the 90 d than in the 45 d and 60 d groups (P < 0.05). Edema and lymphocytes were increased in the prostatic tissue with the prolonged time of modeling. The levels of serum TNF-α, IL-1ß, IL-2 and IL-10 were markedly elevated in all the CP rats as compared with those in the controls (P < 0.05), and so were the expressions of SP and NK-1R in the L5-S2 spinal cord (P < 0.05), even more significantly in the 90 d than in the 45 d and 60 d groups (P < 0.05). CONCLUSIONS: Rats with chronic prostatitis are characterized by behavioral manifestation of depression, increased levels of serum TNF-α, IL-1ß, IL-2 and IL-10, and a time-dependent upregulation of the expressions of SP and NK-1R in the posterior horn of the L5-S2 spinal cord, which suggests a correlation between the behavioral performance and the expressions of SP and NK-1R in the L5-S2 spinal cord of the rats.


Assuntos
Comportamento Animal , Prostatite/patologia , Receptores da Neurocinina-1/metabolismo , Medula Espinal/metabolismo , Substância P/metabolismo , Animais , Depressão , Interleucina-10/sangue , Interleucina-1beta/sangue , Interleucina-2/sangue , Masculino , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/sangue
14.
Cell Physiol Biochem ; 49(2): 645-652, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30165350

RESUMO

BACKGROUND/AIMS: Excess energy intake leads to metabolic dysfunction, accompanied by oxidative stress and poly(ADP-ribose) polymerase (PARP) activation. METHODS: To determine the role of PARP activation in the incidence of metabolic dysfunction, PJ34, the PARP inhibitor, was administered to the oleic acid-treated hepatoma cells and high-fat diet-fed mice. The expression of genes was detected by quantitative real-time PCR and western blotting. Lipid droplets in the cells and tissues were stained with Oil Red O. RESULTS: PJ34 treatment aggravated oleic acid-induced lipid accumulation in hepatoma cells and induced SREBP1 expression by modulating the modification of transcription factor specificity protein 1 (Sp1). The high-fat diet-mice exhibited hyperglycemia, insulin resistance and lipid accumulation after 3 months of feeding. Although the serum level of lipid was not altered after PJ34 treatment, the expression level of lipogenic gene was up-regulated and the lipid accumulation was increased in the liver tissues of high-fat diet + PJ34-treated mice. In the high-fat diet + PJ34-treated mice, the insulin sensitivity was slightly changed and the levels of blood glucose and serum insulin were decreased compared with the mice fed with a high-fat diet alone. CONCLUSION: Taken together, PARP inhibition up-regulated the expression level of lipogenic gene and significantly induced lipid accumulation in the liver, which might worsen lipid metabolism disorders. These data will guide future research into the application of PARP inhibitors in the management of metabolic diseases.


Assuntos
Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Glicemia/análise , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Dieta Hiperlipídica , Glucose/metabolismo , Insulina/sangue , Lipídeos/sangue , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ácido Oleico/farmacologia , Fenantrenos/farmacologia , Poli(ADP-Ribose) Polimerases/química , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
15.
Anal Chem ; 89(18): 9712-9721, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28826211

RESUMO

Protein glycosylation is an important post-translational modification that plays a crucial role in many biological processes. Because of the low abundance of glycoproteins and high complexity of clinical samples, the development of methods to selectively capture glycoproteins/glycopeptides is crucial to glycoproteomics study. In this work, a kind of highly cross-linked chitosan microspheres (CSMs) was prepared using epichlorhydrine as a cross-linker from chitosan solution in an alkaline/urea aqueous system. The results showed that CSMs had high amino groups content, large surface area, mesoporous structure, good acidic resistance, and high strength by various tests. On the basis of hydrophilic interaction between the polar groups (amino groups and hydroxyl groups) on CSMs and glycan moieties on glycopeptides, the prepared CSMs were applied to specific capture of N-glycopeptides from standard protein digests and complex biological samples (body fluids and tissues). The CSMs exhibited high selectivity (HRP/BSA = 1:100), good sensitivity (4.5 × 10-10 M of HRP), good recovery yield (74.9-106.4%), and high binding capacity (100 mg g-1) in glycopeptides enrichment. Because of the excellent performance in glycopeptides enrichment, CSMs were applied to selectively enrich N-glycopeptides from tryptic digests of human serum and rat brain followed by nanoLC-MS/MS analysis. We identified 194 and 947 unique N-glycosylation sites from 2 µL of human serum and 0.1 mg of rat brain, respectively. Additionally, the extraction time of our method was much shorter than the previously reported methods. Therefore, the fabricated CSMs with desirable properties will find broad application in large-scale and in-depth N-glycoproteome analysis.


Assuntos
Quitosana/química , Reagentes de Ligações Cruzadas/química , Glicopeptídeos/análise , Microesferas , Resistência à Tração , Animais , Encéfalo , Quitosana/síntese química , Reagentes de Ligações Cruzadas/síntese química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Tamanho da Partícula , Porosidade , Ratos , Propriedades de Superfície
16.
Arch Microbiol ; 199(9): 1231-1235, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28573482

RESUMO

A novel actinomycete strain, designated XHU 5301T, was isolated from a hypersaline habitat, China. The strain was aerobic, Gram-stain positive and the optimum NaCl concentration for growth was 7-9% (w/v). Phylogenetic analysis based on an almost-complete 16S rRNA gene sequence of strain XHU 5301T showed that the organism was most closely related to Glycomyces halotolerans TRM 40137T (96.0%). The whole-cell sugar pattern consisted of glucose and galactose. The predominant menaquinone was MK-10(H4), MK-10(H2), and MK-9(H4). The major fatty acids were anteiso-C15: 0, iso-C15: 0, iso-C16: 0, and methyl-C19: 0. The polar lipids consist of diphosphatidylglycerol, phosphatidylglycerol, and one unknown phospholipid. The G+C content of the genomic DNA was 72.5 mol %. The novel species Glycomyces xinjiangensis sp. nov. was proposed, with strain XHU 5301T (=CCTCC AA 2016043T =KCTC 39689T) as the type strain of Glycomyces xinjiangensis.


Assuntos
Actinomycetales , DNA Bacteriano/genética , Actinomycetales/classificação , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases/genética , China , Ecossistema , Ácidos Graxos/análise , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio/análise , Vitamina K 2/análise
17.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 48(2): 309-313, 2017 Mar.
Artigo em Zh | MEDLINE | ID: mdl-28612547

RESUMO

OBJECTIVES: To evaluate the effectiveness of repetitive transcranial magnetic stimulation (rTMS) and sensory cueing (SC) for improving hemi-spatial attention deficits related to unilateral neglect, upper limb function and independence of stroke patients. METHODS: An assessor-blinded randomized controlled trial (RCT) was conducted. Eligible stroke patients were treated with rTMS (n =17) or rTMS combined with SC (n =16) in addition to conventional rehabilitation measures. rTMS was applied with low frequency (1 Hz) over the posterior parietal cortex (P5) of the lefthemisphere, 90% resting motor threshold, 900 pulses each session, one session per day, and 5 d per week for 2 weeks. SC was emitted using a wristwatch device attached to the hemiplegic arm for 2 weeks with a cumulative wear time of 3 h per day. The severity of unilateral neglect [behavioral inattention test conventional subtests (BITC), Catherine Bergego scale (CBS)], activity of daily living [modified Barthel index (MBI)], and upper limb function [Fugl-Meyer assessment (FMA), action research arm test (ARAT)] of the patients were measured pre- and post-interventions (immediately after 2 weeks' treatment) by an occupational therapist. RESULTS: BIT-C was relieved significantly over time in both groups. But rTMS+SC had greater improvement than rTMS alone (P <0.05). No significant differences was found between the two groups in other outcomes (CBS, FMA, ARAT). CONCLUSION: rTMS combined with SC is better than rTMS alone for treating unilateral neglect in stroke patients.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/terapia , Estimulação Magnética Transcraniana , Humanos , Lobo Parietal , Resultado do Tratamento
18.
Pestic Biochem Physiol ; 134: 8-13, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27914544

RESUMO

Three rice planthoppers, brown planthopper, Nilaparvata lugens, white-backed planthopper, Sogatella furcifera and small brown planthopper, Laodelphax striatellus, are important pests of cultivated rice in tropical and temperate Asia. They have caused severe economic loss and developed resistance to insecticides from most chemical classes. Dinotefuran is the third neonicotinoid which possesses a broad spectrum and systemic insecticidal activity. We determined the susceptibility of dinotefuran to field populations from major rice production areas in China from 2013 to 2015. All the populations of S. furcifera and L. striatellus were kept susceptible to dinotefuran (0.7 to 1.4-fold of S. furcifera and 1.1-to 3.4-fold of L. striatellus) However, most strains of N. lugens (except FQ15) collected in 2015 had developed moderate resistance to dinotefuran, with resistance ratios (RR) ranging from 23.1 to 100.0 folds. Cross-resistance studies showed that chlorpyrifos-resistant and buprofezin-resistant Sogatella furcifera, chlorpyrifos-resistant and fipronil-resistant L. striatellus, imidacloprid-resistant and buprofezin-resistant Nilaparvata lugens exhibited negligible or no cross-resistance to dinotefuran. Synergism tests showed that piperonyl butoxide (PBO) produced a high synergism of dinotefuran effects in the DY15 and JS15 populations (2.14 and 2.52-fold, respectively). The obvious increase in resistance to dinotefuran in N. lugens indicates that insecticide resistance management strategies are urgently needed to prevent or delay further increase of insecticide resistance in N. lugens.


Assuntos
Guanidinas/toxicidade , Hemípteros/efeitos dos fármacos , Resistência a Inseticidas , Inseticidas/toxicidade , Nitrocompostos/toxicidade , Animais , China , Imidazóis/toxicidade , Neonicotinoides , Oryza , Sinergistas de Praguicidas/toxicidade , Butóxido de Piperonila/toxicidade , Pirazóis/toxicidade , Tiadiazinas/toxicidade
19.
Biomed Environ Sci ; 29(4): 248-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27241735

RESUMO

OBJECTIVE: To compare the performance of MTBDRplus V2 and Xpert MTB/RIF for detecting smear negative pulmonary tuberculosis (PTB). METHODS: Clinical PTB suspects were enrolled consecutively in Anhui Chest Hospital and Xi'an Chest Hospital from January to December in 2014. The sputum samples of smear negative PTB suspects were collected and decontaminated. The sediment was used to conduct MTBDRplus V2, Xpert MTB/RIF and drug susceptibility test (DST). All the samples with discrepant drug susceptibility result between molecular methods and phenotypic method were confirmed by DNA sequencing. RESULTS: A total of 1973 cases were enrolled in this study. The detection rates of Mycobacterium tuberculosis complex (MTBC) by MTBDRplus V2 and Xpert MTB/RIF were 27.67% and 27.98%, respectively. When setting MGIT culture result as a gold standard, the sensitivity and specificity of MTBDRplus V2 were 86.74% and 93.84%, and the sensitivity and specificity of Xpert MTB/RIF were 86.55% and 93.43%, respectively. For the detection of the resistance to rifampin, the sensitivity and specificity of MTBDRplus V2 were 94.34% and 96.62%, and the sensitivity and specificity of Xpert MTB/RIF were 88.68% and 95.96%, respectively. For the detection of the resistance to isoniazid, the sensitivity and specificity of MTBDRplus V2 were 77.38% and 98.02%, respectively. CONCLUSION: MTBDRplus V2 and Xpert MTB/RIF can be used to detect MTBC in smear negative samples with satisfactory performance.


Assuntos
Técnicas Bacteriológicas/métodos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Pulmonar/diagnóstico , Antituberculosos/farmacologia , Farmacorresistência Bacteriana , Humanos , Isoniazida/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Sensibilidade e Especificidade , Tuberculose Pulmonar/microbiologia
20.
Angew Chem Int Ed Engl ; 55(14): 4456-60, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-26937844

RESUMO

Total syntheses of the biologically important and structurally unique tetracyclic diterpenes conidiogenone, conidiogenol, and conidiogenone B of the cyclopiane class are reported. The absolute configuration of naturally occurring conidiogenone B was also corrected. The key step of our strategy involved the highly efficient construction of both ring C and the quaternary carbon center shared by rings A and C through a one-step regioselective and diastereoselective cycloenlargement in the form of a semipinacol-type rearrangement. In particular, the desired regioselectivity was made possible by properly adjusting the migratory aptitude of the migrating carbon atom through the introduction of an electron-donating phenylthio group at this position.


Assuntos
Diterpenos/síntese química , Cristalografia por Raios X , Diterpenos/química , Estrutura Molecular
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