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1.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(5): 437-443, 2024 May 15.
Artigo em Zh | MEDLINE | ID: mdl-38802901

RESUMO

The UK screening and treatment of retinopathy of prematurity (ROP) updated 2022 guidelines were developed by a multidisciplinary guideline development group from the Royal College of Paediatrics and Child Health and the Royal College of Ophthalmologists, following the standards of the National Institute for Health and Care Excellence. They were published on the websites of the Royal College of Paediatrics and Child Health and the Royal College of Ophthalmologists in March 2022, and formally published in Early Human Development in March 2023. The guidelines provide evidence-based recommendations for the screening and treatment of ROP. The most significant change in the 2022 updated version compared to the previous guidelines is the lowering of the gestational age screening criterion to below 31 weeks. The treatment section covers treatment indications, timing, methods, and follow-up visits of ROP. This article interprets the guidelines and compares them with ROP guidelines/consensus in China, providing a reference for domestic peers.


Assuntos
Guias de Prática Clínica como Assunto , Retinopatia da Prematuridade , Humanos , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/terapia , Recém-Nascido , Reino Unido , Triagem Neonatal , Idade Gestacional
2.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(1): 90-95, 2022 Jan 15.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-35177182

RESUMO

OBJECTIVES: To study the association of fractional exhaled nitric oxide (FeNO) and nasal nitric oxide (nNO) with asthma control and their value in the diagnosis of allergic rhinitis in children. METHODS: A total of 186 children aged 5-12 years, who attended the outpatient service of the Department of Respiration, Shanghai Children's Hospital due to bronchial asthma and/or allergic rhinitis or who underwent physical examination, were enrolled as subjects, with 52 children in the asthma group, 60 children in the asthma+allergic rhinitis group, 36 children in the allergic rhinitis group, and 38 children in the control group. FeNO, nNO, and pulmonary function were compared between groups. RESULTS: The asthma+allergic rhinitis, asthma, and allergic rhinitis groups had a significantly higher level of FeNO than the control group (P<0.05). The asthma+allergic rhinitis and allergic rhinitis groups had a significantly higher level of nNO than the asthma and control groups (P<0.05). The uncontrolled asthma and partially controlled asthma groups had significantly higher levels of FeNO and nNO than the completely controlled asthma group (P<0.05). The receiver operating characteristic (ROC) curve analysis showed that nNO had an area under the ROC curve of 0.91, with a sensitivity of 80.0% and a specificity of 89.5% in the diagnosis of allergic rhinitis in children with asthma (P<0.05). CONCLUSIONS: The combined measurement of nNO and FeNO can be used to evaluate the control of asthma, and the measurement of nNO can help with the diagnosis of allergic rhinitis in children with bronchial asthma.


Assuntos
Asma , Rinite Alérgica , Asma/diagnóstico , Testes Respiratórios , Criança , Pré-Escolar , China , Teste da Fração de Óxido Nítrico Exalado , Humanos , Óxido Nítrico/análise , Rinite Alérgica/diagnóstico
3.
Molecules ; 26(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34500581

RESUMO

In this paper, the organocatalytic asymmetric 1,4-Michael addition reaction of azadienes and α-thiocyanoindanones was investigated. A series of chiral benzofuran compounds containing thiocyano group and quaternary carbon center were synthesized in moderate yields with good enantioselectivities (up to 90:10 er) and high diastereoselectivities (up to >95:5 dr). This is the first case of 1,4-Michael addition reaction using α-thiocyanoindanones to obtain a series of chiral thiocyano compounds and further broaden the scope of application of azadiene substrates. In addition, a possible reaction mechanism is also described in the article.

4.
J Mol Recognit ; 31(6): e2697, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29318655

RESUMO

Dysfunctional accumulation of amyloid ß-protein (Aß) mediated by Cu2+ exhibits higher neurotoxicity and accelerates the progress of Alzheimer's disease, so inhibition of Cu2+ -mediated Aß aggregation and cytotoxicity has been considered as a therapeutic strategy for the disease. Herein, a nonapeptide was designed by linking HH to the C-terminus of a peptide inhibitor of Aß aggregation, LVFFARK (LK7). We found that the nonapeptide, LK7-HH, possessed dual functionality, including enhanced inhibition capability on Aß aggregation as compared to LK7, and chelating Cu2+ with a dissociation constant of 5.50 µM. This enabled LK7-HH to arrest the generation of reactive oxygen species catalyzed by Cu2+ or Cu2+ -Aß complex, and to inhibit Cu2+ -induced Aß aggregation. Moreover, in contrast with the cytotoxicity of LK7 aggregates, LK7-HH was biocompatible because HH conjugation made its aggregation behavior different from LK7. Thus, LK7-HH efficiently suppressed Cu2+ -mediated Aß aggregation and cytotoxicity. An equimolar concentration of LK7-HH increased cell viability from 50% to 90% when treating Aß40 -Cu2+ complexes. The results provided insights into the roles of HH in enhancing the inhibition of Aß and Cu2+ -induced Aß aggregations, in eliminating Cu2+ -induced cytotoxicities by arresting generation of reactive oxygen species, and in making the peptide biocompatible. Therefore, this work would contribute to the design of potent peptide-based inhibitors of Cu2+ -mediated Aß aggregation and cytotoxicity.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Quelantes/farmacologia , Peptídeos/química , Agregação Patológica de Proteínas/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quelantes/química , Cobre/toxicidade , Humanos , Peptídeos/genética , Peptídeos/farmacologia , Agregados Proteicos/genética , Agregação Patológica de Proteínas/induzido quimicamente , Agregação Patológica de Proteínas/patologia , Espécies Reativas de Oxigênio/química
5.
Psychol Health Med ; 23(10): 1239-1249, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29699414

RESUMO

To investigate the association of personality traits with breast cancer risk, a case-control study was conducted from May 2014 to February 2017, in which the case group consisted of 262 women with breast cancer and 262 without (control group). The Eysenck Personality Questionnaire (EPQ) (88-question Adult Edition) and another self-assessment questionnaire that contained open questions to obtain more specific character traits were used to complete this survey. The results of the E scale showed that 121 women (46.18%) in the case group and 94 women (35.88%) in the control group were extroverted. The results of the N scale showed that 150 women (57.25%) in the case group and 86 women (32.82%) in the control group had unstable personality. Adjusting for other confounding factors, extroversion and unstable personality were risk factors for breast cancer (E scale: OR = 1.70, 95% CI = 1.28-2.15; N scale: OR = 3.18, 95% CI = 1.77-4.91). Personality instability was a higher risk factor than extroversion was. People with unstable personalities were 3.18 times more likely to have breast cancer than were those who had stable personalities. The results of the self-assessment questionnaire suggested that the more frequent character traits mentioned were being concerned over everything, irritable, and perfectionistic, seeking to prevail over others, and being manipulative and oversensitive.


Assuntos
Neoplasias da Mama/epidemiologia , Personalidade , Adulto , Idoso , Neoplasias da Mama/psicologia , Estudos de Casos e Controles , China/epidemiologia , Extroversão Psicológica , Feminino , Humanos , Pessoa de Meia-Idade , Neuroticismo , Inventário de Personalidade , Fatores de Risco , Inquéritos e Questionários
6.
Int J Nurs Pract ; 23(1)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28054402

RESUMO

This study aimed to identify the association between demographic characteristics, health behaviors, self-management abilities, and disease severity among patients with chronic obstructive pulmonary disease (COPD). The study was conducted from January to December 2015 in 4 hospitals in China. The DOSE index was assessed by grade of dyspnea (D), airflow obstruction (O), current smoking status (S), and frequency of exacerbation in the last year (E). Self-management abilities were assessed by the COPD self-management scale. DOSE index associations with demographic characteristics, health behaviors, and self-management abilities were examined with multiple regression analysis. In total, 100 participants were recruited into the study. In univariate analysis, higher symptom management, lower daily life management, and lower self-efficacy in self-management abilities were significantly related to higher DOSE index. In multiple regression analysis, physical activity, body mass index, and gender were negatively related to DOSE index. The study highlighted the importance of physical activity, nutritional status, and gender difference in managing disease severity in COPD. Professional nurses should develop individualized intervention programs and specifically increase physical activity for men and poor nutritional status for patients with COPD.


Assuntos
Comportamentos Relacionados com a Saúde , Doença Pulmonar Obstrutiva Crônica/psicologia , Doença Pulmonar Obstrutiva Crônica/terapia , Autogestão , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , China , Estudos Transversais , Demografia , Dispneia/etiologia , Dispneia/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Doença Pulmonar Obstrutiva Crônica/complicações , Análise de Regressão , Autoeficácia
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(10): 1056-61, 2015 Oct.
Artigo em Zh | MEDLINE | ID: mdl-26483223

RESUMO

OBJECTIVE: To study the distribution of pathogenic microorganisms in different genders, age groups and seasons in children with community-acquired pneumonia (CAP) and the relationship between the distribution of pathogenic microorganisms and clinical features. METHODS: A total of 1,155 children with CAP were enrolled, among whom there were 670 boys and 485 girls, with a mean age of 3.1±2.8 years (range: one month to 14 years). Indirect immunofluorescence assay, particle agglutination test, enzyme-linked immunosorbent assay, colloidal gold method. and bacterial culture were applied to determine common respiratory pathogenic microorganisms in sputum, throat swabs, blood samples, bronchoalveolar lavage fluid, and urine. RESULTS: A total of 758 specimens (65.63%) were tested positive by pathogen detection. The top three dominant pathogens were Mycoplasma pneumoniae (MP, 43.64%), bacteria (15.12%), and respiratory syncytial virus (RSV, 9.26%), and the rate of mixed infection was 16.02%. The rates of MP infection between boys and girls with CAP were different (40.8% vs 47.6%; P<0.05). The MP detection rate was the highest in the age group of 6-14 years (77.4%) and the lowest in children younger than 1 year (11.2%), while the detection rates of bacteria and RSV were the highest in children younger than 1 year (21.2% and 17.2%, respectively). The MP detection rate was significantly higher in summer and autumn than in winter and spring, while the detection rates of bacteria and RSV in summer and autumn were significantly lower than those in winter and spring. Among children who were MP positive, fever, chills, cough, crackles were more likely to appear; children with RSV infection were more likely to have wheezes; children with bacterial infection were less likely to have cough. Serum levels of C-reactive protein and procalcitonin were associated with bacterial infection (OR=1.747 and 1.418, respectively; both P<0.05). CONCLUSIONS: MP plays a more and more important role in the pathogenic microorganisms of CAP in children. Prevalence and outbreaks of MP infection among children should be alerted in summer and autumn. There are differences in the detection rate of various pathogenic microorganisms in CAP children with various age groups. The clinical features of children with CAP caused by different pathogenic microorganisms are different.


Assuntos
Infecções Comunitárias Adquiridas/microbiologia , Pneumonia/microbiologia , Adolescente , Bactérias/isolamento & purificação , Proteína C-Reativa/análise , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/virologia , Feminino , Humanos , Lactente , Masculino , Pneumonia/virologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Estações do Ano
8.
Langmuir ; 30(32): 9789-96, 2014 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-25083748

RESUMO

Alzheimer's disease (AD) is the most prevalent form of dementia, and aggregation of amyloid ß-proteins (Aß) into soluble oligomers and fibrils has been implicated in the pathogenesis of AD. Herein we developed acidulated serum albumin for the inhibition of Aß42 fibrillogenesis. Bovine serum albumin (BSA) was modified with diglycolic anhydride, leading to the coupling of 14.5 more negative charges (carboxyl groups) on average on each protein surface. The acidulated BSA (A-BSA) was characterized and confirmed to keep the tertiary structure and stability of BSA. Extensive biophysical and biological analyses showed that A-BSA significantly inhibited Aß42 fibrillogenesis and mitigated amyloid cytotoxicity. As compared to the Aß42-treated group (cell viability, 50%), the cell viability increased to 88% by the addition of equimolar A-BSA. The inhibitory effect was remarkably higher than that of BSA at the same concentration. On the basis of the experimental findings, a mechanistic model was proposed. The model considers that Aß42 is bound to the A-BSA surface by hydrophobic interactions, but the widely distributed negative charges on the A-BSA surface give rise to electrostatic repulsions to the bound Aß42 that is also negatively charged. The two well-balanced opposite forces make Aß42 adopt extended conformations instead of the ß-sheet structure that is necessary for the on-pathway fibrillogenesis, even when the protein is released off the surface. Thus, A-BSA greatly slows down the fibrillation and changes the fibrillogenesis pathway, leading to the formation of less toxic aggregates. The findings and the mechanistic model offer new insights into the development of more potent inhibitors of Aß fibrillogenesis and cytotoxicity.


Assuntos
Peptídeos beta-Amiloides/química , Soroalbumina Bovina/química , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células PC12 , Ratos , Soroalbumina Bovina/efeitos adversos
9.
World J Pediatr ; 20(1): 11-25, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38064012

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is the leading global cause of respiratory infections and is responsible for about 3 million hospitalizations and more than 100,000 deaths annually in children younger than 5 years, representing a major global healthcare burden. There is a great unmet need for new agents and universal strategies to prevent RSV infections in early life. A multidisciplinary consensus development group comprising experts in epidemiology, infectious diseases, respiratory medicine, and methodology aims to develop the current consensus to address clinical issues of RSV infections in children. DATA SOURCES: The evidence searches and reviews were conducted using electronic databases, including PubMed, Embase, Web of Science, and the Cochrane Library, using variations in terms for "respiratory syncytial virus", "RSV", "lower respiratory tract infection", "bronchiolitis", "acute", "viral pneumonia", "neonatal", "infant" "children", and "pediatric". RESULTS: Evidence-based recommendations regarding diagnosis, treatment, and prevention were proposed with a high degree of consensus. Although supportive care remains the cornerstone for the management of RSV infections, new monoclonal antibodies, vaccines, drug therapies, and viral surveillance techniques are being rolled out. CONCLUSIONS: This consensus, based on international and national scientific evidence, reinforces the current recommendations and integrates the recent advances for optimal care and prevention of RSV infections. Further improvements in the management of RSV infections will require generating the highest quality of evidence through rigorously designed studies that possess little bias and sufficient capacity to identify clinically meaningful end points.


Assuntos
Bronquiolite , Infecções por Vírus Respiratório Sincicial , Infecções Respiratórias , Criança , Humanos , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Consenso , Vírus Sinciciais Respiratórios , Infecções Respiratórias/epidemiologia , Hospitalização
10.
J Chem Phys ; 139(22): 225102, 2013 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-24329094

RESUMO

P-glycoprotein (P-gp), a kind of ATP-binding cassette transporter, can export candidates through a channel at the two transmembrane domains (TMDs) across the cell membranes using the energy released from ATP hydrolysis at the two nucleotide-binding domains (NBDs). Considerable evidence has indicated that human P-gp undergoes large-scale conformational changes to export a wide variety of anti-cancer drugs out of the cancer cells. However, molecular mechanism of the conformational transmission of human P-gp from the NBDs to the TMDs is still unclear. Herein, targeted molecular dynamics simulations were performed to explore the atomic detail of the conformational transmission of human P-gp. It is confirmed that the conformational transition from the inward- to outward-facing is initiated by the movement of the NBDs. It is found that the two NBDs move both on the two directions (x and y). The movement on the x direction leads to the closure of the NBDs, while the movement on the y direction adjusts the conformations of the NBDs to form the correct ATP binding pockets. Six key segments (KSs) protruding from the TMDs to interact with the NBDs are identified. The relative movement of the KSs along the y axis driven by the NBDs can be transmitted through α-helices to the rest of the TMDs, rendering the TMDs to open towards periplasm in the outward-facing conformation. Twenty eight key residue pairs are identified to participate in the interaction network that contributes to the conformational transmission from the NBDs to the TMDs of human P-gp. In addition, 9 key residues in each NBD are also identified. The studies have thus provided clear insight into the conformational transmission from the NBDs to the TMDs in human P-gp.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/química , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Trifosfato de Adenosina/metabolismo , Membrana Celular/metabolismo , Humanos , Hidrólise , Simulação de Dinâmica Molecular , Nucleotídeos/metabolismo , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos
11.
J Chem Phys ; 136(14): 145101, 2012 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-22502547

RESUMO

Aggregation of amyloid-ß (Aß) peptides correlates with the pathology of Alzheimer's disease. However, the inter-molecular interactions between Aß protofibril remain elusive. Herein, molecular mechanics Poisson-Boltzmann surface area analysis based on all-atom molecular dynamics simulations was performed to study the inter-molecular interactions in Aß(17-42) protofibril. It is found that the nonpolar interactions are the important forces to stabilize the Aß(17-42) protofibril, while electrostatic interactions play a minor role. Through free energy decomposition, 18 residues of the Aß(17-42) are identified to provide interaction energy lower than -2.5 kcal/mol. The nonpolar interactions are mainly provided by the main chain of the peptide and the side chains of nine hydrophobic residues (Leu17, Phe19, Phe20, Leu32, Leu34, Met35, Val36, Val40, and Ile41). However, the electrostatic interactions are mainly supplied by the main chains of six hydrophobic residues (Phe19, Phe20, Val24, Met35, Val36, and Val40) and the side chains of the charged residues (Glu22, Asp23, and Lys28). In the electrostatic interactions, the overwhelming majority of hydrogen bonds involve the main chains of Aß as well as the guanidinium group of the charged side chain of Lys28. The work has thus elucidated the molecular mechanism of the inter-molecular interactions between Aß monomers in Aß(17-42) protofibril, and the findings are considered critical for exploring effective agents for the inhibition of Aß aggregation.


Assuntos
Peptídeos beta-Amiloides/química , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/química , Multimerização Proteica , Ligação de Hidrogênio , Distribuição de Poisson , Estrutura Secundária de Proteína , Propriedades de Superfície , Termodinâmica
12.
Ying Yong Sheng Tai Xue Bao ; 33(9): 2539-2546, 2022 Sep.
Artigo em Zh | MEDLINE | ID: mdl-36131671

RESUMO

To clarify the mechanisms underlying the improvement of Trichoderma on Chinese wolfberry (Lycium chinense) growth under saline stress, we analyzed the effects of application of organic fertilizer, Trichoderma agent and fertilizer on nitrogen uptake, assimilation, accumulation and use efficiency in Chinese wolfberry, based on a pot experiment with coastal saline soil. The organic fertilizer was the sterilization substance of Trichoderma fertilizer without viable Trichoderma, without any difference in the content of nutrients (such as nitrogen, phosphorus and potassium) between them. The results showed that the application of organic fertilizer, Trichoderma agent and ferti-lizer significantly increased NO3- and NH4+ influx rate in meristematic zone and NO3- influx rate in maturation zone of roots. The magnitude of such enhancement was greater in the application with Trichoderma fertilizer than organic fertilizer. Compared with the control, the application of Trichoderma agent and fertilizer significantly increased root, stem and leaf biomass and nitrogen content as well as plant nitrogen accumulation, strengthened root and leaf nitrate reductase, nitrite reductase and glutamine synthetase activities, and elevated nitrogen uptake efficiency, photosynthetic rate, stable carbon isotope abundance and photosynthetic nitrogen use efficiency. For all those variables, the beneficial effect was obviously stronger in the application with Trichoderma fertilizer than organic fertilizer. Therefore, Trichoderma facilitated nitrogen uptake, assimilation and accumulation in Chinese wolfberry under saline stress, improved photosynthetic carbon fixation ability and nitrogen use efficiency, and ultimately promoted plant growth.


Assuntos
Lycium , Trichoderma , Isótopos de Carbono , Fertilizantes/análise , Glutamato-Amônia Ligase , Nitrito Redutases , Nitrogênio/análise , Fósforo , Potássio , Solo
13.
Biotechnol Bioeng ; 108(5): 1068-77, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21190266

RESUMO

Protein refolding is a crucial step for the production of therapeutic proteins expressed in bacteria as inclusion bodies. In vitro protein refolding is severely impeded by the aggregation of folding intermediates during the folding process, so inhibition of the aggregation is the most effective approach to high-efficiency protein refolding. We have herein found that electrostatic repulsion between like-charged protein and ion exchange gel beads can greatly suppress the aggregation of folding intermediates, leading to the significant increase of native protein recovery. This finding is extensively demonstrated with three different proteins and four kinds of ion-exchange resins when the protein and ion-exchange gel are either positively or negatively charged at the refolding conditions. It is remarkable that the enhancing effect is significant at very high protein concentrations, such as 4 mg/mL lysozyme (positively charged) and 2 mg/mL bovine serum albumin (negatively charged). Moreover, the folding kinetics is not compromised by the presence of the resins, so fast protein refolding is realized at high protein concentrations. It was not realistic by any other approaches. The working mechanism of the like-charged resin is considered due to the charge repulsion that could induce oriented alignment of protein molecules near the charged surface, leading to the inhibition of protein aggregation. The molecular crowding effect induced by the charge repulsion may also contribute to accelerating protein folding. The refolding method with like-charged ion exchangers is simple to perform, and the key material is easy to separate for recycling. Moreover, because ion exchangers can work as adsorbents of oppositely charged impurities, an operation of simultaneous protein refolding and purification is possible. All the characters are desirable for preparative refolding of therapeutic proteins expressed in bacteria as inclusion bodies.


Assuntos
Resinas de Troca Iônica , Dobramento de Proteína , Proteínas/química , Eletricidade Estática
14.
Brain Behav Immun ; 24(8): 1281-93, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20595065

RESUMO

Anti-beta-amyloid (Aß) immunotherapy is effective in removing brain Aß, but has shown to be associated with detrimental effects. We have demonstrated that Adeno-associated virus (AAV)-mediated delivery of an anti-Aß single chain antibody (scFv) gene was effective in clearing brain Aß without eliciting any inflammatory side effects in old APP(Swe)/PS1dE9 transgenic mice. In the present study, we tested the efficacy and safety of intramuscular delivery of the scFv gene in preventing brain Aß deposition. The scFv gene was intramuscularly delivered to APP(Swe)/PS1dE9 transgenic mice at 3 months of age, prior to Aß deposition in the brain. Six months later, we found that the transgenes were expressed in a stable form at the delivered sites, with a small amount of ectopic expression in the liver and olfactory bulb. Brain Aß plaque formation, Aß accumulation, AD-type pathologies and cognitive impairment were significantly attenuated in scFv-treated APP(Swe)/PS1dE9 transgenic mice relative to EGFP-treated mice. Intramuscular delivery of scFv gene was well tolerated by the animals, did not cause inflammation or microhemorrhage at the gene expression site and in the brain, and did not induce neutralizing antibodies in the animals. These findings suggest that peripheral application of scFv is effective and safe in preventing the development of Alzheimer's disease (AD), and would be a promising non-inflammatory immunological modality for prevention and treatment of AD.


Assuntos
Vacinas contra Alzheimer/uso terapêutico , Peptídeos beta-Amiloides/imunologia , Química Encefálica/efeitos dos fármacos , Transtornos Cognitivos/imunologia , Transtornos Cognitivos/prevenção & controle , Anticorpos de Cadeia Única/farmacologia , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Transtornos Cognitivos/psicologia , Citocinas/sangue , Citocinas/metabolismo , Dependovirus/genética , Ensaio de Imunoadsorção Enzimática , Vetores Genéticos , Humanos , Processamento de Imagem Assistida por Computador , Injeções Intramusculares , Camundongos , Camundongos Transgênicos , Presenilinas/genética , Anticorpos de Cadeia Única/administração & dosagem
15.
J Chem Phys ; 132(22): 225103, 2010 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-20550422

RESUMO

Molecular dynamics simulations of chymotrypsin inhibitor 2 in different polyols (glycerol, xylitol, sorbitol, trehalose, and sucrose) at 363 K were performed to probe the molecular basis of the stabilizing effect, and the data in water, ethanol, and glycol were compared. It is found that protein protection by polyols is positively correlated with both the molecular volume and the fractional polar surface area, and the former contributes more significantly to the protein's stability. Polyol molecules have only a few direct hydrogen bonds with the protein, and the number of hydrogen bonds between a polyol and the protein is similar for different polyols. Thus, it is concluded that the direct interactions contribute little to the stabilizing effect. It is clarified that the preferential exclusion of the polyols is the origin of their protective effects, and it increases with increasing polyol size. Namely, there is preferential hydration on the protein surface (2 A), and polyol molecules cluster around the protein at a distance of about 4 A. The preferential exclusion of polyols leads to indirect interactions that prevent the protein from thermal unfolding. The water structure becomes more ordered with increasing the polyol size. So, the entropy of water in the first hydration shell decreases, and a larger extent of decrease is observed with increasing polyol size, leading to larger transfer free energy. The findings suggest that polyols protect the protein from thermal unfolding via indirect interactions. The work has thus elucidated the molecular mechanism of structural stability of the protein in polyol solutions.


Assuntos
Simulação de Dinâmica Molecular , Peptídeos/química , Proteínas de Plantas/química , Polímeros/farmacologia , Peptídeos/metabolismo , Proteínas de Plantas/metabolismo , Polímeros/metabolismo , Estabilidade Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína , Propriedades de Superfície , Temperatura
16.
World J Pediatr ; 16(4): 326-332, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32588213

RESUMO

During the COVID-19 epidemic, it is important for ensuring infection prevention and control in the pediatric respiratory clinics. Herein, we introduced the practice of infection prevention and control in pediatric respiratory clinics in China. Triage measures for patients who visit respiratory clinics, quality control for pediatric respiratory clinics and other preventive measures for related examinations and treatment have been introduced in this review article.


Assuntos
Assistência Ambulatorial/organização & administração , Controle de Doenças Transmissíveis/organização & administração , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Guias de Prática Clínica como Assunto , Doenças Respiratórias/terapia , Adolescente , Instituições de Assistência Ambulatorial/organização & administração , COVID-19 , Criança , Pré-Escolar , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Controle de Infecções/organização & administração , Masculino , Pandemias/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Doenças Respiratórias/diagnóstico , Doenças Respiratórias/epidemiologia
17.
Electrophoresis ; 30(4): 689-95, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19170054

RESUMO

A novel negatively charged tentacle-type polymer-coated capillary column was fabricated and applied for on-line extraction and preconcentration of proteins. The polymer coating was prepared by glycidyl-methacrylate graft polymerization in a silanized capillary column and the following sulfonic acid group functionalization. It had high surface area and offered high phase ratio for protein adsorption. In addition, the polymer-coated capillary column provided more stable EOF than a bare uncoated capillary. These features of the polymer coating facilitated the extraction of proteins through electrostatic interactions. This was used to extract proteins. The extracted analytes were then desorbed and focused by EOF in the direction opposite to the sample injection flow for subsequent CE. With this procedure, over 1500-fold sensitivity enhancement was realized for myoglobin (MB) as compared with a normal capillary zone electrophoresis. By comparison of the peak areas of the enriched protein, it was found that the polymer-coated column could capture proteins about 30 times more than the uncoated column. In addition, the separation of a protein mixture containing 0.4 microg/mL of MB and 0.4 microg/mL of insulin was demonstrated by the on-line preconcentration and electrophoretic separation with the polymer-coated column.


Assuntos
Eletroforese Capilar/métodos , Compostos de Epóxi/química , Metacrilatos/química , Polímeros/química , Proteínas/química , Eletro-Osmose , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Microscopia Eletrônica de Varredura , Proteínas/isolamento & purificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
J Phys Chem B ; 113(32): 11320-9, 2009 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-19719268

RESUMO

Soluble amyloid oligomers are a cytotoxic species in Alzheimer's disease, and the recent discovery that trehalose can prohibit aggregation of amyloid beta-peptide (Abeta) has received great attention. However, its inhibition mechanism remains unclear. In order to investigate the molecular mechanism of the inhibition effect, molecular dynamics simulations of Abeta(16-22) and Abeta(40) peptides at different trehalose concentrations (0-0.18 mol/L) are performed using an all-atom model. The simulations confirmed that Abeta(16-22) aggregation is prevented by trehalose in a dose-dependent manner, and it is found that the preferential exclusion effect of trehalose is the origin of its inhibition effects. Namely, there is preferential hydration on the peptide surface (3 A), and trehalose molecules cluster around the peptides at a distance of 4-5 A. At high trehalose concentrations, the preferential exclusion of trehalose leads to three sequential effects that prevent the nucleation and elongation of Abeta(16-22) oligomers. First, the secondary structures of Abeta(16-22) monomers are stabilized in the turn, bend, or coil, so the beta-sheet-rich structure that is prone to forming peptide oligomers is prevented. Second, the thin hydration layer and trehalose clusters can weaken hydrophobic interactions that lead to Abeta(16-22) aggregation. Third, more direct and indirect H-bonds form between trehalose and Abeta(16-22), which suppress the interpeptide hydrogen bonding. Analyses of the simulation data for a single Abeta(40) peptide indicate that trehalose can inhibit the nucleation and elongation of Abeta(40) by a similar mechanism with that on Abeta(16-22) oligomerization. The work has thus elucidated the molecular mechanism of trehalose on the inhibition of Abeta oligomeric aggregation.


Assuntos
Peptídeos beta-Amiloides/química , Biopolímeros/química , Peptídeos/química , Trealose/química , Ligação de Hidrogênio , Estrutura Secundária de Proteína
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