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1.
Int J Mol Sci ; 21(5)2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32121503

RESUMO

: Catalpa bungei is an economically important tree with high-quality wood and highly valuable to the study of wood formation. In this work, the xylem microstructure of C. bungei tension wood (TW) was observed, and we performed transcriptomics, proteomics and Raman spectroscopy of TW, opposite wood (OW) and normal wood (NW). The results showed that there was no obvious gelatinous layer (G-layer) in the TW of C. bungei and that the secondary wall deposition in the TW was reduced compared with that in the OW and NW. We found that most of the differentially expressed mRNAs and proteins were involved in carbohydrate polysaccharide synthesis. Raman spectroscopy results indicated that the cellulose and pectin content and pectin methylation in the TW were lower than those in the OW and NW, and many genes and proteins involved in the metabolic pathways of cellulose and pectin, such as galacturonosyltransferase (GAUT), polygalacturonase (PG), endoglucanase (CLE) and ß-glucosidase (BGLU) genes, were significantly upregulated in TW. In addition, we found that the MYB2 transcription factor may regulate the pectin degradation genes PG1 and PG3, and ARF, ERF, SBP and MYB1 may be the key transcription factors regulating the synthesis and decomposition of cellulose. In contrast to previous studies on TW with a G-layer, our results revealed a change in metabolism in TW without a G-layer, and we inferred that the change in the pectin type, esterification and cellulose characteristics in the TW of C. bungei may contribute to high tensile stress. These results will enrich the understanding of the mechanism of TW formation.


Assuntos
Bignoniaceae/genética , Bignoniaceae/metabolismo , Perfilação da Expressão Gênica , Pectinas/metabolismo , Proteômica , Transcriptoma/genética , Madeira/metabolismo , Parede Celular/metabolismo , Celulose/biossíntese , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Redes Reguladoras de Genes , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polissacarídeos/biossíntese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise Espectral Raman , Madeira/anatomia & histologia , Madeira/genética
2.
Ann Hepatol ; 16(6): 888-892, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29055925

RESUMO

PURPOSE: This study aims to investigate the antiviral effect of polyethylene glycol (PEG)-interferon α-2a and PEG-interferon α-2b treatment on hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) at the 48th week of treatment and the 24th and 48th week after withdrawal, in order to provide guidance on the antiviral treatment of HBeAg-positive CHB patients. MATERIAL AND METHODS: Antiviral treatment was performed on 155 HBeAg-positive CHB patients. Among these patients, 66 patients received PEG-interferon α-2a treatment and 89 patients received PEG-interferon α-2b treatment; and these treatments were administered by subcutaneous injection, once per week, which lasted for 48 weeks. Other antiviral and hepatoprotective drugs were not used during the treatment. RESULTS: At the 48th week of treatment, ALT recovery rate, HBsAg seroconversion rate, HBeAg seroconversion rate and HBV DNA titers dropped below 200 IU/mL rate were 69.7%, 6.1%, 27.3% and 50.0%, respectively, in the PEG-interferon α-2a group; and were 70.8%, 6.7%, 33.7% and 62.9%, respectively, in the PEG-interferon α-2b group. At the 24th and 48th week of follow-up after withdrawal, HBsAg seroconversion rate in these two groups did not change; and HBeAg seroconversion rate further increased. Furthermore, HBV DNA revealed a low recurrence rate. The difference between these two groups was not significantly significant. CONCLUSIONS: PEG-interferon α-2a and PEG-interferon α-2b are effective antiviral drugs for the treatment of HbeAgpositive CHB, which has a HBsAg seroconversion rate of more than 5%. Furthermore, this sustained response effect was maintained at the 24th and 48th week of follow-up after withdrawal.


Assuntos
Antivirais/uso terapêutico , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adulto , Antivirais/efeitos adversos , Biomarcadores/sangue , DNA Viral/sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/sangue , Hepatite B Crônica/diagnóstico , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Polietilenoglicóis/efeitos adversos , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Recidiva , Estudos Retrospectivos , Soroconversão , Fatores de Tempo , Resultado do Tratamento , Carga Viral , Adulto Jovem
3.
BMC Infect Dis ; 14: 645, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-25471294

RESUMO

BACKGROUND: Infants who are exclusively breastfed receive natural protection against some infectious agents. This study examined whether there was protective effect of exclusive breastfeeding on the occurrence of hand, foot and mouth disease, which was an emerging infectious disease among children in China. METHODS: A community-based case-control study was carried out among children age 4 years or younger in Guangdong Province, China. Cases were newly diagnosed hand, foot and mouth disease. Controls were randomly sampled from healthy children from the nearby village. Unconditional logistic regression model was used to estimate the odds ratio (OR) for exclusive breastfeeding after adjusting for potential confounding factors. RESULTS: A total of 316 cases and 566 controls were included in the analysis. Significantly beneficial effect of exclusive breastfeeding during the first 6 months was observed for hand, foot and mouth disease occurrence. The overall OR was 0.63 (95% CI: 0.47-0.85) for exclusive breastfeeding compared with mixed feeding type. The age-specific analyses indicated that the protective effect persisted till the age of 28 months. CONCLUSIONS: This study suggests that exclusive breastfeeding might have protective effect against HFMD infection among the children within 28 months of age.


Assuntos
Aleitamento Materno , Doenças Transmissíveis Emergentes/prevenção & controle , Doença de Mão, Pé e Boca/prevenção & controle , Fatores Etários , Estudos de Casos e Controles , Pré-Escolar , China/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/imunologia , Serviços de Saúde Comunitária , Intervalos de Confiança , Feminino , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/imunologia , Humanos , Lactente , Entrevistas como Assunto , Masculino , Razão de Chances , Fatores de Risco
4.
ACS Appl Mater Interfaces ; 15(19): 22915-22928, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37155948

RESUMO

Ideal joint wound dressings should not only promote wound healing and have good mechanical properties including stretchability and adhesion but also possess functions such as sterilization or motion monitoring. The multiple characteristic requirements have greatly limited the material's alternative, resulting in research on functional joint wound dressings falling far short of market demand. Therefore, low-cost, comprehensive designs need to be developed. Herein, inspired by the spiral arteries in the endometrium, alginate-based helical fibers were introduced into polyacrylamide/gelatin (PAM-Gel) to obtain composite polymer membranes, realizing a combination of both mechanical and functional properties. Large scale (100 m) and high-throughput (10 times higher than literature) fabrication of helical microfibers were first achieved, ensuring the low cost of fiber preparation. The composite film had adequate stretchability (>300% strain), adhesion strength (14 kPa), high transparency, and good biocompatibility. The helical fibers could be easily functionalized without affecting the mechanical properties of the dressings, thus broadening the range of materials available for joint dressings. After different treatments of the helical fibers, controlled drug release and joint motion monitoring were realized. Therefore, this helical microfiber composite membrane design achieved low-cost preparation, good mechanical properties, and functionalities including healing promotion, drug release, and motion monitoring ability, demonstrating application potential.


Assuntos
Adesivos , Cicatrização , Feminino , Humanos , Bandagens , Polímeros , Hidrogéis
5.
Biosensors (Basel) ; 12(8)2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36005055

RESUMO

Cell encapsulation has been widely employed in cell therapy, characterization, and analysis, as well as many other biomedical applications. While droplet-based microfluidic technology is advantageous in cell microencapsulation because of its modularity, controllability, mild conditions, and easy operation when compared to other state-of-art methods, it faces the dilemma between high throughput and monodispersity of generated cell-laden microdroplets. In addition, the lack of a biocompatible method of de-emulsification transferring cell-laden hydrogel from cytotoxic oil phase into cell culture medium also hurtles the practical application of microfluidic technology. Here, a novel step-T-junction microchannel was employed to encapsulate cells into monodisperse microspheres at the high-throughput jetting regime. An alginate-gelatin co-polymer system was employed to enable the microfluidic-based fabrication of cell-laden microgels with mild cross-linking conditions and great biocompatibility, notably for the process of de-emulsification. The mechanical properties of alginate-gelatin hydrogel, e.g., stiffness, stress-relaxation, and viscoelasticity, are fully adjustable in offering a 3D biomechanical microenvironment that is optimal for the specific encapsulated cell type. Finally, the encapsulation of HepG2 cells into monodisperse alginate-gelatin microgels with the novel microfluidic system and the subsequent cultivation proved the maintenance of the long-term viability, proliferation, and functionalities of encapsulated cells, indicating the promising potential of the as-designed system in tissue engineering and regenerative medicine.


Assuntos
Alginatos , Microgéis , Encapsulamento de Células , Gelatina , Hidrogéis , Microesferas
6.
J Infect ; 85(4): 428-435, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35768049

RESUMO

Enterovirus A71 (EV71) vaccination program was introduced in 2016 in China. Based on a longitudinal surveillance dataset from 2012 to 2019 in Guangdong, China, we estimated the impact of the EV71 vaccination program on hand, foot, and mouth disease (HFMD) incidence, by using a counterfactual prediction made from synthetic control approach integrated with a Bayesian time-series model. We observed a relative reduction of 41.4% for EV71-associated HFMD cases during the post-vaccination period of 2017-2019, corresponding to 26,226 cases averted. The reduction of EV71-associated HFMD cases raised with the elevation of EV71 vaccine coverage by year. We found an indirect effect for the children aged 6-14 years who were less likely to be vaccinated. Whereas, the EV71 vaccine may not protect against non-EV71-associated HFMD. This study provides a template for ongoing public health surveillance of EV71 vaccine effectiveness with a counterfactual study design. Our results show strong evidence of the EV71 vaccination program working on reducing EV71-associated HFMD in real-world settings. The finding will benefit policy-making of EV71 vaccination and the prevention of HFMD.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Doença de Mão, Pé e Boca , Teorema de Bayes , Criança , China/epidemiologia , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/prevenção & controle , Humanos , Lactente , Vacinação
7.
Lancet Reg Health West Pac ; 17: 100282, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34611630

RESUMO

Background: Nonpharmaceutical interventions (NPIs) are public health measures that aim to suppress the transmission of infectious diseases, including border restrictions, quarantine and isolation, community management, social distancing, face mask usage, and personal hygiene. This research aimed to assess the co-benefits of NPIs against COVID-19 on notifiable infectious diseases (NIDs) in Guangdong Province, China. Methods: Based on NID data from the Notifiable Infectious Diseases Surveillance System in Guangdong, we first compared the incidence of NIDs during the emergency response period (weeks 4-53 of 2020) with those in the same period of 2015-2019 and then compared that with the expected incidence during the synchronous period of 2020 for each city by using a Bayesian structural time series model. Findings: A total of 514,341 cases of 39 types of NIDs were reported in Guangdong during the emergency response period in 2020, which decreased by 50·7% compared with the synchronous period during 2015-2019. It was estimated that the number of 39 NIDs during the emergency response in 2020 was 65·6% (95% credible interval [CI]: 64·0% - 68·2%) lower than expected, which means that 982,356 (95% CI: 913,443 - 1,105,170) cases were averted. The largest reduction (82·1%) was found for children aged 0-14 years. For different categories of NIDs, natural focal diseases and insect-borne infectious diseases had the greatest reduction (89·4%), followed by respiratory infectious diseases (87·4%), intestinal infectious diseases (59·4%), and blood-borne and sexually transmitted infections (18·2%). Dengue, influenza, and hand-foot-and-mouth disease were reduced by 99·3%, 95·1%, and 76·2%, respectively. Larger reductions were found in the regions with developed economies and a higher number of COVID-19 cases. Interpretation: NPIs against COVID-19 may have a large co-benefit on the prevention of other infectious diseases in Guangdong, China, and the effects have heterogeneity in populations, diseases, time and space. Funding: Key-Area Research and Development Program of Guangdong Province.

8.
Plant Signal Behav ; 15(4): 1735755, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32141360

RESUMO

Abscisic acid (ABA)-induced stomatal closure can improve drought tolerance in higher plants. However, the relationship between ABA-related ion flux and improved drought resistance in the roots of woody plants is unclear. To investigate this relationship, we employed a noninvasive micro-test technique (NMT) to detect potassium (K+) flux in Catalpa fargesii and C. fargesii f. duclouxii after treatment with polyethylene glycol (PEG) and ABA. PEG treatment slightly increased the free proline content in both Catalpa species. However, simultaneous treatment with ABA and PEG resulted in a large increase in free proline content. Treatment with PEG led to a significant increase in K+ efflux, and both ABA and tetraethylammonium (TEA, a K+ channel inhibitor) blocked this efflux under short-term (1 d) and long-term (7 d) drought conditions. Furthermore, we detected SKOR (stelar K+ outward-rectifying channel) gene expression in roots, and the results showed that PEG significantly increased SKOR expression in C. fargesii f. duclouxii, but SKOR expression was inhibited by ABA in Catalpa fargesii. These findings indicate that ABA improves drought tolerance by inhibiting K+ efflux in Catalpa, but distinct ABA response patterns exist. Drought-tolerant species have better potassium retention are dependent on ABA, and can accumulate more proline than other species. SKOR is also ABA-dependent and sensitive to ABA, and K+ flux is a target of the ABA-mediated drought response.


Assuntos
Ácido Abscísico/metabolismo , Bignoniaceae/metabolismo , Secas , Ecossistema , Potássio/metabolismo , Ácido Abscísico/farmacologia , Bignoniaceae/efeitos dos fármacos , Bignoniaceae/genética , Transporte Biológico/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Polietilenoglicóis/farmacologia , Prolina/metabolismo
9.
Am J Infect Control ; 44(2): e13-4, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26803935

RESUMO

Although it is an enteroviral infectious disease, recent studies suggest that respiratory transmission might play a role in the transmission of hand, foot, and mouth disease (HFMD). We evaluated the transmission modes (respiratory and fecal-oral transmission) of HFMD among children using a case-control study in Guangdong, China. Our analyses suggested that fecal-oral transmission might be the principal transmission mode of HFMD among children in the study area, and handwashing habits of the children and their parents should be emphasized to control this infection.


Assuntos
Enterovirus/fisiologia , Doença de Mão, Pé e Boca/transmissão , Controle de Infecções , Estudos de Casos e Controles , Pré-Escolar , China/epidemiologia , Fezes/virologia , Feminino , Desinfecção das Mãos , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , Humanos , Lactente , Masculino , Boca/virologia
10.
Clin Orthop Relat Res ; 464: 83-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17589362

RESUMO

UNLABELLED: Operative options for the younger patient with an arthritic knee remain controversial. We prospectively followed 1047 patients 55 years old or younger who underwent knee arthroplasty in a community joint registry over a 14-year period. Patients were implanted with 1047 joints of three predominant designs by 48 surgeons in four hospitals associated with a community joint registry. The mean age for this cohort was 49.8 years, and 62.8% (657/1047) of the patients were female. There were a total of 73 revisions performed, 5.6% (37/653) in women and 9.2% (36/394) in men. Cemented TKAs performed best, with a cumulative revision rate of 15.5%, compared to 32.3% in unicompartmental knee arthroplasty (UKA) patients and 34.1% in cementless designs. Men had a higher cumulative revision rate than women, 31.9% compared to 20.6%. Adjusting for implant type and gender, there was no difference in cumulative revision rate based on diagnosis (OA versus other) or age group (< or = 40, 41-45, 46-50, 51-55 years) or between cruciate-retaining and -substituting designs. Eighty five percent of cemented TKA implants survived at 14 years in the population under 55 years of age in this community registry. Cementless designs and UKA increased revision risk independently. LEVEL OF EVIDENCE: Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.


Assuntos
Artroplastia do Joelho/estatística & dados numéricos , Prótese do Joelho/estatística & dados numéricos , Osteoartrite do Joelho/cirurgia , Sistema de Registros/estatística & dados numéricos , Reoperação/estatística & dados numéricos , Adulto , Distribuição por Idade , Cimentos Ósseos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/epidemiologia , Estudos Prospectivos , Falha de Prótese , Fatores de Risco , Resultado do Tratamento
11.
Clin Orthop Relat Res ; 464: 88-92, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17589363

RESUMO

UNLABELLED: The advantages of the monoblock design and lower cost have prompted renewed interest in the all-polyethylene tibia in total knee arthroplasty. We prospectively followed patients with all-polyethylene tibial total knee arthroplasties over a 14-year period. Since 1991, 443 total knee arthroplasties using an all-polyethylene tibia component were implanted by 12 surgeons in four hospitals associated with a community registry. One of three designs was used in over 98% of cases. The mean age of the patient population was 77 years and 78% were female. Ninety-three patients died with their prosthesis intact. Three revisions were performed on this population with mean followup of 66.3 months (range, 0-158 months). Kaplan-Meier survival analysis revealed 99.4% survival at 14.3 years with revision for any reason as the end point. With aseptic loosening or wear as the revision reason, survival is 99.7% at 14.3 years. Total knee arthroplasty with one of the three contemporary congruent all-polyethylene tibia designs used in this registry performed extremely well in this population; savings for this group (compared to those with a metal-backed component) was estimated at $729 per case. If all patients older than 75 years of age in our registry had received an all-polyethylene tibia, the estimated savings for the implant alone would have been $1.28 million. LEVEL OF EVIDENCE: Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.


Assuntos
Artroplastia do Joelho/estatística & dados numéricos , Prótese do Joelho/estatística & dados numéricos , Polietileno , Sistema de Registros/estatística & dados numéricos , Tíbia/cirurgia , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho/economia , Redução de Custos , Feminino , Humanos , Estimativa de Kaplan-Meier , Articulação do Joelho/cirurgia , Prótese do Joelho/economia , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Falha de Prótese , Reoperação/estatística & dados numéricos , Fatores de Risco , Resultado do Tratamento
13.
Nano Lett ; 7(8): 2307-11, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17629347

RESUMO

We report the direct synthesis of strong, highly conducting, and transparent single-walled carbon nanotube (SWNT) films. Systematically, tests reveal that the directly synthesized films have superior electrical and mechanical properties compared with the films made from a solution-based filtration process: the electrical conductivity is over 2000 S/cm and the strength can reach 360 MPa. These values are both enhanced by more than 1 order. We attribute these intriguing properties to the good and long interbundle connections. Moreover, by the help of an extrapolated Weibull theory, we verify the feasibility of reducing the interbundle slip by utilizing the long-range intertube friction and estimate the ultimate strength of macroscale SWNTs without binding agent.


Assuntos
Cristalização/métodos , Membranas Artificiais , Nanotecnologia/métodos , Nanotubos/química , Nanotubos/ultraestrutura , Elasticidade , Dureza , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície , Resistência à Tração
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