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1.
Ren Fail ; 46(1): 2294151, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38178374

RESUMO

BACKGROUND: Previous studies have shown that intravenous normal saline (NS) may be associated with the incidence of acute kidney injury (AKI). This study aimed to evaluate the association between the volume of NS infusion and AKI in heat stroke (HS) patients. METHODS: This multicenter retrospective cohort study included 138 patients with HS. The primary outcome was the incidence of AKI. Secondary outcomes included the need for continuous renal replacement therapy (CRRT), admission to the intensive care unit (ICU), length of stay in the ICU and hospital, and in-hospital mortality. Multivariate regression models, random forest imputation, and genetic and propensity score matching were used to explore the relationship between NS infusion and outcomes. RESULTS: The mean volume of NS infusion in the emergency department (ED) was 3.02 ± 1.45 L. During hospitalization, 33 patients (23.91%) suffered from AKI. In the multivariate model, as a continuous variable (per 1 L), the volume of NS infusion was associated with the incidence of AKI (OR, 2.51; 95% CI, 1.43-4.40; p = .001), admission to the ICU (OR, 3.46; 95% CI 1.58-7.54; p = .002), and length of stay in the ICU (ß, 1.00 days; 95% CI, 0.44-1.56; p < .001) and hospital (ß, 1.41 days; 95% CI, 0.37-2.45; p = .008). These relationships also existed in the forest imputation cohort and matching cohort. There were no differences in the use of CRRT or in-hospital mortality. CONCLUSIONS: The volume of NS infusion was associated with a significant increase in the incidence of AKI, admission to the ICU, and length of stay in the ICU and hospital among patients with HS.


Assuntos
Injúria Renal Aguda , Golpe de Calor , Humanos , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Serviço Hospitalar de Emergência , Unidades de Terapia Intensiva , Estudos Retrospectivos , Solução Salina
2.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612657

RESUMO

Huntington's disease (HD) arises from the abnormal expansion of CAG repeats in the huntingtin gene (HTT), resulting in the production of the mutant huntingtin protein (mHTT) with a polyglutamine stretch in its N-terminus. The pathogenic mechanisms underlying HD are complex and not yet fully elucidated. However, mHTT forms aggregates and accumulates abnormally in neuronal nuclei and processes, leading to disruptions in multiple cellular functions. Although there is currently no effective curative treatment for HD, significant progress has been made in developing various therapeutic strategies to treat HD. In addition to drugs targeting the neuronal toxicity of mHTT, gene therapy approaches that aim to reduce the expression of the mutant HTT gene hold great promise for effective HD therapy. This review provides an overview of current HD treatments, discusses different therapeutic strategies, and aims to facilitate future therapeutic advancements in the field.


Assuntos
Doença de Huntington , Humanos , Doença de Huntington/genética , Doença de Huntington/terapia , Terapia Genética , Proteínas Mutantes
3.
Infect Immun ; 91(9): e0021323, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37607057

RESUMO

Streptococcus pneumoniae, a common cause of community-acquired bacterial pneumonia, can cross the respiratory epithelial barrier to cause lethal septicemia and meningitis. S. pneumoniae pore-forming toxin pneumolysin (PLY) triggers robust neutrophil (PMN) infiltration that promotes bacterial transepithelial migration in vitro and disseminated disease in mice. Apical infection of polarized respiratory epithelial monolayers by S. pneumoniae at a multiplicity of infection (MOI) of 20 resulted in recruitment of PMNs, loss of 50% of the monolayer, and PMN-dependent bacterial translocation. Reducing the MOI to 2 decreased PMN recruitment two-fold and preserved the monolayer, but apical-to-basolateral translocation of S. pneumoniae remained relatively efficient. At both MOI of 2 and 20, PLY was required for maximal PMN recruitment and bacterial translocation. Co-infection by wild-type S. pneumoniae restored translocation by a PLY-deficient mutant, indicating that PLY can act in trans. Investigating the contribution of S. pneumoniae infection on apical junction complexes in the absence of PMN transmigration, we found that S. pneumoniae infection triggered the cleavage and mislocalization of the adherens junction (AJ) protein E-cadherin. This disruption was PLY-dependent at MOI of 2 and was recapitulated by purified PLY, requiring its pore-forming activity. In contrast, at MOI of 20, E-cadherin disruption was independent of PLY, indicating that S. pneumoniae encodes multiple means to disrupt epithelial integrity. This disruption was insufficient to promote bacterial translocation in the absence of PMNs. Thus, S. pneumoniae triggers cleavage and mislocalization of E-cadherin through PLY-dependent and -independent mechanisms, but maximal bacterial translocation across epithelial monolayers requires PLY-dependent neutrophil transmigration.


Assuntos
Junções Aderentes , Streptococcus pneumoniae , Animais , Camundongos , Proteínas de Bactérias , Caderinas
4.
J Org Chem ; 88(13): 8400-8412, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37350730

RESUMO

An unprecedented copper and in situ-generated triflic acid relay-promoted four-component cascade reaction of cyanamides, diaryliodonium triflates, propargylic amines, and H2O was established for rapid and concise construction of diverse five-membered cycloguanidines. Copper-catalyzed guanidination/intramolecular hydroamination and in situ-generated HOTf-accelerated hydration proceeded sequentially with high level of chemoselectivity and regioselectivity, and six new bonds were simultaneously built in high yields. Thus, diaryliodonium triflates served not only as an arylation reagent but also as an internal acid promoter, establishing an alternative strategy for highly efficient utilization of diaryliodonium trifates.

5.
Inorg Chem ; 62(51): 21396-21408, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38060836

RESUMO

The construction of efficient photocatalysts for water splitting to enable H2 evolution is pivotal to alleviate energy issues and environmental concerns. In this work, carbon dots (CDs) were prepared by employing "green solvent" ionic liquids as carbon sources and then combined with Pt/NH2-MIL-125, resulting in the emergence of a high-efficiency photocatalyst termed CDs-Pt/NH2-MIL-125 for the first time. This composite photocatalyst exhibited outstanding photocatalytic activity in H2 production under visible light irradiation. Notably, the H2 production rate of CDs100-Pt/NH2-MIL-125 reaches up to 951.4 µmol/g/h, which was 3.1 times that of Pt/NH2-MIL-125. The characterization results indicate that CDs and Pt uniformly dispersed on the surface of NH2-MIL-125 and fabricated a synergistic compact structure, providing a high BET surface area (985 m2 g-1) and a suitable band gap. Furthermore, the distinctive embeddable-dispersed CDs and Pt, as dual cocatalyst, can harvest light and facilitate the transfer of photogenerated electrons, thereby significantly augmenting the exploitation of visible light. The plausible mechanism of photocatalytic H2 evolution over the CDs-Pt/NH2-MIL-125 catalyst was also discussed. This work introduces a promising strategy for designing high-performance CDs-MOFs-based photocatalysts, an innovative step toward achieving efficient photocatalytic water splitting for H2 production.

6.
Environ Res ; 216(Pt 2): 114423, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36228691

RESUMO

Polycarboxylate (PCE) is a high performance superplasticizer for modern concrete. With the high quality sand becoming precious, more and more low quality sands are used in concrete. However, low quality sands generally contain a relatively high content of montmorillonite (MMT), which could seriously reduce the efficiency of PCE. In order to develop PCE suitable for concrete with low quality sands, the absorption behavior on MMT of PCE with different side chains and acid/ether ratio was investigated. In order to explore the effect of MMT on PCE, two macromonomers were selected, isoprene glycol ether 400(TPEG400) and isoprene glycol ether 2400 (TPEG2400), to synthesize six long and short side chain comb-type PCEs with acid-ether ratios of 1.5:1, 2.5:1 and 3.5:1, respectively. The MMT tolerance mechanism of comb-type PCE in MMT-containing cement slurry was examined by FT-IR, DLS, TOC and other analysis. The PCE with long side chain is much easier to be inserted into the layered structure of MMT, resulting in intercalation absorption. The absorption amount of two kinds of side chain PCE on the MMT particles decreased as the acid ether ratio increases. PCE with long side chains showed shear-thickening properties in MMT-containing cement slurry, on the contrary, short side chains showed shear-thinning properties.

7.
Am J Emerg Med ; 72: 7-15, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37451066

RESUMO

OBJECTIVES: Standard base excess (SBE) is a quick and effective tool to identify acid-base disorders in critically ill patients, independent of respiratory factors. The predictive value of SBE for adverse outcomes in patients with heat stroke (HS) is still unclear. This study aimed to explore the prognostic significance of SBE for in-hospital mortality and other adverse outcomes in patients with HS. METHODS: A retrospective, observational multicenter cohort study with consecutive patients between 2021 and 2022 was conducted. The SBE was performed upon emergency department (ED) admission. The primary outcome was in-hospital mortality. Secondary outcomes included the use of vasoactive drugs in the ED, admission to the ICU, acute kidney failure, acute heart failure, acute respiratory failure, sepsis, and coagulation impairment. Logistic regression models and receiver operating characteristic (ROC) curves were used to estimate the association of SBE with outcomes in HS patients. Interaction and stratified analyses were also conducted. RESULTS: The median level of SBE was -4.70 (-8.05- -1.55) mmol/L. Overall hospital mortality in these 151 HS patients was 12.58%. SBE was independently associated with hospital mortality (OR 0.81, 95% CI 0.70-0.95, P = 0.011). Age and HS type played interactive roles in the relationship between SBE and in-hospital mortality. The OR between SBE and hospital mortality was 0.5 (95% CI, 0.3-0.9; p < 0.018) in classic HS participants and 0.62 (95% CI, 0.45-0.87; p = 0.005) in participants aged >65 years. The AUC of SBE to predict in-hospital mortality was 0.868 (95% CI: 0.704-0.962) and 0.883 (95% CI: 0.750-0.951) in these two groups, respectively. SBE was significantly associated with admission to the ICU, acute kidney failure, acute respiratory failure, sepsis, and coagulation impairment. CONCLUSION: SBE upon emergency admission was significantly associated with adverse outcomes in patients with HS.


Assuntos
Injúria Renal Aguda , Golpe de Calor , Insuficiência Respiratória , Sepse , Humanos , Estudos Retrospectivos , Estudos de Coortes , Prognóstico , Mortalidade Hospitalar , Golpe de Calor/complicações , Golpe de Calor/terapia , Curva ROC , Serviço Hospitalar de Emergência , Unidades de Terapia Intensiva
8.
Allergy Asthma Proc ; 44(6): 402-412, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37919842

RESUMO

Background: Rhinitis, allergic rhinitis in particular, and urticaria are both common diseases globally. However, there is controversy with regard to the correlation between rhinitis and urticaria. Objective: To examine the accurate association between rhinitis and urticaria. Methods: Three medical literature data bases were searched from data base inception until January 11, 2022. The prevalence and association between rhinitis and urticaria were estimated by meta-analysis. Quality assessment was performed by using the Newcastle-Ottawa Scale. Pooled odds ratios (OR) with 95% confidence intervals (CI) and pooled prevalence were calculated by using random-effects models. Results: Urticaria prevalence in patients with rhinitis was 17.6% (95% CI, 13.2%-21.9%). The pooled prevalence of rhinitis was 31.3% (95% CI, 24.2%-38.4%) in patients with urticaria, and rhinitis prevalence in patients with acute urticaria and chronic urticaria was 31.6% (95% CI, 7.4%-55.8%) and 28.7% (95% CI, 20.4%-36.9%), respectively. Rhinitis occurrence was significantly associated with urticaria (OR 2.67 [95% CI, 2.625-2.715]). Urticaria and rhinitis were diagnosed based on different criteria, possibly resulting in a potential error of misclassification. Conclusion: Rhinitis and urticaria were significantly correlated. Physicians should be cognizant with regard to this relationship and address nasal or skin symptoms in patients.


Assuntos
Rinite Alérgica Perene , Rinite Alérgica , Rinite , Urticária , Humanos , Rinite/epidemiologia , Prevalência , Urticária/epidemiologia , Rinite Alérgica/epidemiologia
9.
Proc Natl Acad Sci U S A ; 117(52): 33561-33569, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33376222

RESUMO

Streptococcus pneumoniae is a leading cause of pneumonia and invasive disease, particularly, in the elderly. S. pneumoniae lung infection of aged mice is associated with high bacterial burdens and detrimental inflammatory responses. Macrophages can clear microorganisms and modulate inflammation through two distinct lysosomal trafficking pathways that involve 1A/1B-light chain 3 (LC3)-marked organelles, canonical autophagy, and LC3-associated phagocytosis (LAP). The S. pneumoniae pore-forming toxin pneumolysin (PLY) triggers an autophagic response in nonphagocytic cells, but the role of LAP in macrophage defense against S. pneumoniae or in age-related susceptibility to infection is unexplored. We found that infection of murine bone-marrow-derived macrophages (BMDMs) by PLY-producing S. pneumoniae triggered Atg5- and Atg7-dependent recruitment of LC3 to S. pneumoniae-containing vesicles. The association of LC3 with S. pneumoniae-containing phagosomes required components specific for LAP, such as Rubicon and the NADPH oxidase, but not factors, such as Ulk1, FIP200, or Atg14, required specifically for canonical autophagy. In addition, S. pneumoniae was sequestered within single-membrane compartments indicative of LAP. Importantly, compared to BMDMs from young (2-mo-old) mice, BMDMs from aged (20- to 22-mo-old) mice infected with S. pneumoniae were not only deficient in LAP and bacterial killing, but also produced higher levels of proinflammatory cytokines. Inhibition of LAP enhanced S. pneumoniae survival and cytokine responses in BMDMs from young but not aged mice. Thus, LAP is an important innate immune defense employed by BMDMs to control S. pneumoniae infection and concomitant inflammation, one that diminishes with age and may contribute to age-related susceptibility to this important pathogen.


Assuntos
Envelhecimento/imunologia , Interações Hospedeiro-Patógeno/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Fagocitose , Streptococcus pneumoniae/imunologia , Animais , Autofagia , Proteínas de Bactérias/metabolismo , Lipídeos/química , Macrófagos/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Viabilidade Microbiana , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Streptococcus pneumoniae/ultraestrutura , Estreptolisinas/metabolismo
10.
J Immunol ; 202(11): 3256-3266, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31010852

RESUMO

Tetraspanins are a family of proteins possessing four transmembrane domains that help in lateral organization of plasma membrane proteins. These proteins interact with each other as well as other receptors and signaling proteins, resulting in functional complexes called "tetraspanin microdomains." Tetraspanins, including CD82, play an essential role in the pathogenesis of fungal infections. Dectin-1, a receptor for the fungal cell wall carbohydrate ß-1,3-glucan, is vital to host defense against fungal infections. The current study identifies a novel association between tetraspanin CD82 and Dectin-1 on the plasma membrane of Candida albicans-containing phagosomes independent of phagocytic ability. Deletion of CD82 in mice resulted in diminished fungicidal activity, increased C. albicans viability within macrophages, and decreased cytokine production (TNF-α, IL-1ß) at both mRNA and protein level in macrophages. Additionally, CD82 organized Dectin-1 clustering in the phagocytic cup. Deletion of CD82 modulates Dectin-1 signaling, resulting in a reduction of Src and Syk phosphorylation and reactive oxygen species production. CD82 knockout mice were more susceptible to C. albicans as compared with wild-type mice. Furthermore, patient C. albicans-induced cytokine production was influenced by two human CD82 single nucleotide polymorphisms, whereas an additional CD82 single nucleotide polymorphism increased the risk for candidemia independent of cytokine production. Together, these data demonstrate that CD82 organizes the proper assembly of Dectin-1 signaling machinery in response to C. albicans.


Assuntos
Candida albicans/fisiologia , Candidíase/metabolismo , Membrana Celular/metabolismo , Proteína Kangai-1/metabolismo , Lectinas Tipo C/metabolismo , Macrófagos/imunologia , Fagossomos/metabolismo , Animais , Candidíase/imunologia , Linhagem Celular , Predisposição Genética para Doença , Humanos , Imunidade Celular , Interleucina-1beta/metabolismo , Proteína Kangai-1/genética , Lectinas Tipo C/genética , Microdomínios da Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Polimorfismo de Nucleotídeo Único , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
11.
FASEB J ; 33(11): 12500-12514, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31408613

RESUMO

The tetraspanin CD82 is a potent suppressor of tumor metastasis and regulates several processes including signal transduction, cell adhesion, motility, and aggregation. However, the mechanisms by which CD82 participates in innate immunity are unknown. We report that CD82 is a key regulator of TLR9 trafficking and signaling. TLR9 recognizes unmethylated cytosine-phosphate-guanine (CpG) motifs present in viral, bacterial, and fungal DNA. We demonstrate that TLR9 and CD82 associate in macrophages, which occurs in the endoplasmic reticulum (ER) and post-ER. Moreover, CD82 is essential for TLR9-dependent myddosome formation in response to CpG stimulation. Finally, CD82 modulates TLR9-dependent NF-κB nuclear translocation, which is critical for inflammatory cytokine production. To our knowledge, this is the first time a tetraspanin has been implicated as a key regulator of TLR signaling. Collectively, our study demonstrates that CD82 is a specific regulator of TLR9 signaling, which may be critical in cancer immunotherapy approaches and coordinating the innate immune response to pathogens.-Khan, N. S., Lukason, D. P., Feliu, M., Ward, R. A., Lord, A. K., Reedy, J. L., Ramirez-Ortiz, Z. G., Tam, J. M., Kasperkovitz, P. V., Negoro, P. E., Vyas, T. D., Xu, S., Brinkmann, M. M., Acharaya, M., Artavanis-Tsakonas, K., Frickel, E.-M., Becker, C. E., Dagher, Z., Kim, Y.-M., Latz, E., Ploegh, H. L., Mansour, M. K., Miranti, C. K., Levitz, S. M., Vyas, J. M. CD82 controls CpG-dependent TLR9 signaling.


Assuntos
Núcleo Celular/imunologia , Proteína Kangai-1/imunologia , Macrófagos/imunologia , Oligodesoxirribonucleotídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Receptor Toll-Like 9/imunologia , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Transporte Ativo do Núcleo Celular/genética , Transporte Ativo do Núcleo Celular/imunologia , Animais , Núcleo Celular/genética , Citocinas/genética , Citocinas/imunologia , Retículo Endoplasmático/genética , Retículo Endoplasmático/imunologia , Retículo Endoplasmático/patologia , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Proteína Kangai-1/genética , Macrófagos/patologia , Camundongos , Camundongos Knockout , NF-kappa B/genética , NF-kappa B/imunologia , Células RAW 264.7 , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Receptor Toll-Like 9/genética
12.
Sensors (Basel) ; 20(9)2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403350

RESUMO

The massive Internet of Things (IoT) connecting various types of intelligent sensors for goods tracking in logistics, environmental monitoring and smart grid management is a crucial future ICT. High-end security and low power consumption are major requirements in scaling up the IoT. In this research, we propose an efficient data-hiding scheme to deal with the security problems and power saving issues of multimedia communication among IoT devises. Data hiding is the practice of hiding secret data into cover images in order to conceal and prevent secret data from being intercepted by malicious attackers. One of the established research streams of data-hiding methods is based on reference matrices (RM). In this study, we propose an efficient data-hiding scheme based on multidimensional mini-SuDoKu RM. The proposed RM possesses high complexity and can effectively improve the security of data hiding. In addition, this study also defines a range locator function which can significantly improve the embedding efficiency of multidimensional RM. Experimental results show that our data-hiding scheme can not only obtain better image quality, but also achieve higher embedding capacity than other related schemes.

13.
Langmuir ; 35(39): 12722-12730, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31536357

RESUMO

Spin-coating was evaluated as a technique to study events that occur during polydopamine (PDA) thin-film formation. The reaction variants studied included type of oxidant, dopamine (DA) concentration, pH, adhesion time prior to spin, substrate chemistry, and notably, DA solution aging time. A strong oxidant, sodium periodate (SP), and a weak oxidant, atmospheric oxygen were chosen. It was found that reactions in solution were much faster and produced much thicker PDA films with SP than with oxygen. PDA thickness correlated positively with DA concentration, SP solution pH, and adhesion time. DA oxidation and aggregation is a dynamic process, which is reflected in the DA aging-time parameter. PDA film thickness reached a maximum value as DA solution aged. Color photography, UV-vis spectroscopy, and dynamic light scattering indicated that the optimal DA aging time for PDA adhesion is the result of the evolution of PDA particle size and chemistry over time. The capture of the optimal aging-time window was identified as the critical parameter for preparing PDA films with continuity and appreciable thickness. When these conditions were applied in a modified dip-coating method, comparable PDA films were fabricated as those obtained from spin-coating. Native silicon wafers (SiO2) as well as wafers that were modified with polydimethylsiloxane (PDMS) and amine-containing polydimethylsiloxane (PADMS) were chosen to represent a wide range of substrates with different substrate-PDA interactions. The main effect of substrate structural difference was on PDA film morphology. "Island" morphologies were obtained on PDMS where only hydrophobic interactions are responsible for PDA adhesion, while "speck" morphologies were observed on SiO2 and PADMS. The stabilities of the fabricated PDA films were tested in 0.1 M HCl and DMSO. The SP-derived PDA films exhibited very little mass loss compared to those fabricated using either the conventional dip-coating method or oxygen as an oxidant. Choosing a strong oxidant, understanding the DA reaction dynamics, and taking advantage of the optimal DA aging time are important in the fabrication of stable PDA films on a variety of substrates.

14.
Molecules ; 23(6)2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29874799

RESUMO

Neoagaro-oligosaccharides (NAOS) have health benefits that are related to their amount and degree of polymerization (DP). However, the current methods that are used to quantify enzymatically released NAOS are un-specific and time-consuming. Agar has been extracted from Gelidium amansii and has been degraded by AgaXa (a recombinant ß-agarase). Polysaccharide analysis using carbohydrate gel electrophoresis (PACE) has been adapted in order to quantify NAOS. In addition, the anti-oxidant activity of the degraded samples has been assessed. We have found that the PACE method provided sensitive, precise, and accurate quantification for each of the six NAOS samples. PACE has revealed that the DP of the enzymatic products from the AgaXa digestion were mainly neoagaro-octaose and neoagaro-decaose. The degraded samples exhibited increased radical-scavenging activity towards 2,2-diphenyl-1-picrylhydrazyl and 2,2-azino-bis(3-ethylbenzothiazoline sulfonic acid) radicals. While the anti-oxidant activity may have been from NAOS activity and contributions from neoagaro-octaose and neoagaro-decaose. The adapted PACE method that has been presented here is promising for large sample analysis during quality control and for characterizing novel ß-agarase degradation mechanisms.


Assuntos
Antioxidantes/farmacologia , Enzimas/metabolismo , Sequestradores de Radicais Livres/farmacologia , Oligossacarídeos/análise , Eletroforese/métodos , Hidrólise , Limite de Detecção , Oligossacarídeos/biossíntese , Oligossacarídeos/metabolismo , Reprodutibilidade dos Testes
15.
J Sep Sci ; 40(8): 1784-1795, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28168817

RESUMO

A capillary electrophoretic method for the enantioseparation of ofloxacin and its five related substances (potential impurities, indicated as impurities B-F) was developed using ß-cyclodextrin derivatives as chiral selectors. To our knowledge, there are no previous studies about using capillary electrophoresis for the separation of impurities B-D. Six ß-cyclodextrin derivatives including cationic (piperidine- and cyclohexylamine-), neutral (dimethyl- and hydroxypropyl-), and anionic (carboxymethyl- and sulfated-) ß-cyclodextrin derivatives were tested and operational parameters such as buffer pH and concentration of ß-cyclodextrin derivatives were investigated. The best resolutions were all obtained with anionic ß-cyclodextrin derivatives: ofloxacin, impurities C-F could be best resolved with carboxymethyl-ß-cyclodextrin at satisfactory resolutions of 8.27, 9.98, 5.92, 8.49 and 6.78, respectively, while for impurity B, a particularly impressive resolution value, up to 21.38, was observed using sulfated-ß-cyclodextrin. The enhancement of enantioseparation observed for the tested analytes using anionic ß-cyclodextrin derivatives might be due to some favorable interaction between selectors and analytes. Given the fact that the selection of chiral selector depends on the structures of analytes, with the help of structural similarities and differences of the analytes, the structure-separation relationship was further discussed.


Assuntos
Eletroforese Capilar , Ofloxacino/isolamento & purificação , beta-Ciclodextrinas/química , Ânions , Estereoisomerismo
16.
Med Sci Monit ; 23: 2842-2849, 2017 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-28601889

RESUMO

BACKGROUND Breast cancer is one of the most common malignancies in women. In a previous study, we found that for two patients who had a high risk of lymphatic metastasis, lymphatic metastasis did not occur; whereas, for two patients who had a low risk of lymphatic metastasis, lymphatic metastasis did occur. MATERIAL AND METHODS We analyzed the differential gene expressions of these four patients by RNA-sequence. The data (HRNM_T versus HRNM_N, LRYM_T versus LRYM_N, and HRNM_T versus LRYM_T) was then processed using differentially expressed genes (DEGs) analysis, functional analysis for DEGs, and PPI network construct. RESULTS For HRNM_T versus HRNM_N, there were 224 DEGs. There were 504 DEGs for LRYM_T versus LRYM_N, and 88 DEGs for LRYM_T versus LRYM_N. For HRNM_T versus HRNM_N, DEGs were up-regulated mainly in the cell cycle, the IL-17 signaling pathway, and the progesterone-mediated oocyte maturation; DEGs were down-regulated mainly in the IL-17 signaling pathway. For LRYM_T versus LRYM_N, DEGs were up-regulated mainly in protein digestion and absorption, and cytokine-cytokine receptor interaction; DEGs were down-regulated mainly in ECM-receptor interaction. For HRNM_T versus LRYM_T, DEGs were up-regulated mainly in the PPAR signaling pathway; DEGs were downregulated mainly in the adipocytokine signaling pathway. The DEGs were screened to construct PPI networks. CONCLUSIONS The GO and KEGG functional enrichments of HRNM_T versus HRNM_N, and LRYM_T versus LRYM_N were consistent with earlier studies. For HRNM_T versus LRYM_T, DEGs were up-regulated mainly in PPAR signaling; DEGs were down-regulated mainly in the adipocytokine pathway.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Perfilação da Expressão Gênica , Metástase Linfática/patologia , Análise de Sequência de RNA , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Pessoa de Meia-Idade , Mapas de Interação de Proteínas , Fatores de Risco , Regulação para Cima/genética
17.
Mar Drugs ; 15(12)2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29236064

RESUMO

Marine algae have attracted a great deal of interest as excellent sources of nutrients. Polysaccharides are the main components in marine algae, hence a great deal of attention has been directed at isolation and characterization of marine algae polysaccharides because of their numerous health benefits. In this review, extraction and purification approaches and chemico-physical properties of marine algae polysaccharides (MAPs) are summarized. The biological activities, which include immunomodulatory, antitumor, antiviral, antioxidant, and hypolipidemic, are also discussed. Additionally, structure-function relationships are analyzed and summarized. MAPs' biological activities are closely correlated with their monosaccharide composition, molecular weights, linkage types, and chain conformation. In order to promote further exploitation and utilization of polysaccharides from marine algae for functional food and pharmaceutical areas, high efficiency, and low-cost polysaccharide extraction and purification methods, quality control, structure-function activity relationships, and specific mechanisms of MAPs activation need to be extensively investigated.


Assuntos
Alimento Funcional , Polissacarídeos/farmacologia , Alga Marinha/química , Relação Estrutura-Atividade , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Antivirais/química , Antivirais/farmacologia , Carboidratos da Dieta/farmacologia , Humanos , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Peso Molecular , Monossacarídeos/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação
18.
J Sep Sci ; 37(1-2): 151-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24170554

RESUMO

A CE method employing a dual system of hydroxypropyl-ß-cyclodextrin (HP-ß-CD) and ionic liquids (ILs) has been developed for the simultaneous enantioseparation of four azole antifungals for the first time. In this study, three different types of ILs were employed as modifiers and among them dodecyl trimethyl ammonium chloride was found to be the most effective. The effects of the concentration, cations, and anions of ILs on the enantioseparation were investigated. With the developed dual system, all the enantiomers were well separated in resolutions of 3.8, 3.5, 2.8, and 2.5 for miconazole, econazole, ketoconazole, and itraconazole, respectively. The interactions between dodecyl trimethyl ammonium chloride and HP-ß-CD were also studied using a neutral polyacrylamide coated capillary and (1) H NMR spectroscopy to further explore the synergistic effect involved. It was found that ILs improved the enantioseparation not only by changing the EOF, but also by interactions with HP-ß-CD that could change its ability of forming inclusion complex with the enantiomers.


Assuntos
Antifúngicos/química , Azóis/química , Eletroforese Capilar/métodos , Antifúngicos/isolamento & purificação , Azóis/isolamento & purificação , Ciclodextrinas/química , Eletroforese Capilar/instrumentação , Líquidos Iônicos/química , Estereoisomerismo
19.
Biomed Chromatogr ; 28(1): 135-41, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23893795

RESUMO

A new capillary electrophoresis (CE) method using carboxymethyl-ß-cyclodextrin (CM-ß-CD) as chiral selector has been developed for the enantiomeric separation of meptazinol and its three intermediate enantiomers (intermediates II-IV), and validated for the application of quantitative determination of meptazinol in tablets. The primary factors affecting the separation efficiency, which include the chiral selector and its concentration, the buffer pH and composition, the organic modifiers used, and the applied voltage, were optimized. Baseline and satisfactory separations were obtained for meptazinol and its three intermediate enantiomers. For quantitative analysis of meptazinol, the method was performed at the condition using 2.0 mmol/L CM-ß-CD in 20 mmol/L H3 PO4 buffer adjusted to a pH of 6.00 with an applied voltage of 15 kV and containing 5% acetonitrile. After validation of the method in terms of its linearity, limits of detection and quantitation, accuracy, precision and selectivity, the method was successfully applied to the quantitation of meptazinol in pharmaceutical formulations.


Assuntos
Eletroforese Capilar/métodos , Meptazinol/química , Adsorção , Química Farmacêutica , Concentração de Íons de Hidrogênio , Meptazinol/isolamento & purificação , Estereoisomerismo , beta-Ciclodextrinas/química
20.
Chem Asian J ; 19(10): e202400161, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38500400

RESUMO

Harnessing low-density solar energy and converting it into high-density chemical energy through photocatalysis has emerged as a promising avenue for the production of chemicals and remediation of environmental pollution, which contributes to alleviating the overreliance on fossil fuels. In recent years, metal-organic frameworks (MOFs) have gained widespread application in the field of photocatalysis due to their photostability, tunable structures, and responsiveness in the visible light range. However, most MOFs exhibit relatively low response to light, limiting their practical applications. MOFs-derived nanomaterials not only retain the inherent advantages of pristine MOFs but also show enhanced light adsorption and responsiveness. This review categorizes and summarizes MOFs-derived nanomaterials, including nanocarbons and nanometal oxides, providing representative examples for the synthetic strategies of each category. Subsequently, the recent research progress on MOFs-derived materials in photocatalytic applications are systematically introduced, specifically in the areas of photocatalytic water splitting to H2, photocatalytic CO2 reduction, and photocatalytic water treatment. The corresponding mechanisms involved in each photocatalytic reaction are elaborated in detail. Finally, the review discusses the challenges and further directions faced by MOFs-derived nanomaterials in the field of photocatalysis, highlighting their potential role in advancing sustainable energy production and environmental remediation.

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