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1.
Plant Dis ; 2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36825313

RESUMEN

Peach (Prunus persica) is an important economic tree fruit in China, with 15 million tons produced in 2020 (Xu et al. 2022). In September 2021, fruit rot on postharvest P. persica 'Yingqingtao' was observed in an orchard warehouse in Qixing district (120°41'E, 29°15'N), Zhejiang Province. Disease incidence was estimated at 25%, and yield loss was estimated at approximately 20% of the total yield. The naturally infected fruit had water-soaked, light brown lesions that fused, and produced a gray-white, dense mycelium (Fig. 1 A). The mycelia were transferred using a sterilized toothpick to potato dextrose agar (PDA) and cultured for 7 d. Macroconidia were used to produce five single-spore isolates, each from a different fruit. Six-day-old colonies grown on PDA at 26°C had light brown centers with gray-white edges; on the underside the centers were reddish brown and white towards the margin (Fig. 1 D). Isolate TGF2 was selected for further identification. Macroconidia were hyaline, straight, cylindrical, and one-to-three septae, 63.2 to 81.8 × 5.7 to 7.8 µm (mean = 73.9 ± 4.3 × 6.9 ± 0.5, n = 30) (Fig. 1 E). Chlamydospores were produced abundantly on PDA (Fig. 1 F), and measured 11.7 to 19.4 × 8.5 to 16.9 µm (n = 10). Perithecia were reddish orange, globose, and 329.9 to 417.1 µm in diameter on PDA (Fig. 1 G). Asci were hyaline and clavate, 61.2 to 91.8 × 14.4 to 20.7 µm (n = 10); ascospores were hyaline, slightly curved, 1- to 3-septate, mostly 1-septate, and 37.6 to 59.7 × 4.9 to 6.4 µm (mean = 49.9 ± 4.5 × 5.6 ± 0.4, n = 30) (Fig. 1 H-J). Morphological characteristics placed this organism within the Ca. kyotensis species complex (Liu et al. 2020). For molecular identification, the internal transcribed spacer (ITS: OP164807-OP164811), calmodulin (Cal: OP176049-OP176053), histone3 (His3: OP176054-OP176058), and translation elongation factor 1α (Tef1: OP176044-OP176048) genes were sequenced (Liu, et al., 2020). The twenty sequences were deposited in GenBank. A BLAST search of these sequences showed 99% identity with sequences of the ex-holotype Ca. ilicicola CMW 30998 (Liu et al. 2020). Bayes phylogenesis suggested that these strains and Ca. ilicicola CMW 30998 were clustered in the same clade (Bayesian posterior probability = 1) (Fig. 2). Integrating morphology and molecular data, these strains were identified as Ca. ilicicola. For pathogenicity tests, P. persica fruits were surface sterilized in 75% ethanol for 30 s and air-dried for 5 mins to allow the alcohol to volatilize. A conidial suspension (30 mL of 1 × 106 conidia/mL) of TGF2 was sprayed onto ten fruits, and ten fruits sprayed with sterilized water served as controls. The experiment was repeated three times. Fruits were kept on a mist bench at 26°C and 60% relative humidity. After 5 days, inoculated fruits showed necrotic lesions and a dense, gray-white mycelium, however, the control fruits showed no symptoms (Fig. 1 B, C). Ca. ilicicola was reisolated from lesions of inoculated fruits. Ca. ilicicola has been reported from Vaccinium sp., Glycine max, Medicago sativa (Farr and Rossman 2022; Kleczewski et al. 2019; Zhang et al. 2020). To our knowledge, this is the first report of Ca. ilicicola causing fruit rot of P. persica in China. In other research on Ca. ilicicola, we found that continuous light could inhibit its growth, suggesting a method to protect postharvest peaches.

2.
Plant Dis ; 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37682226

RESUMEN

Bletilla striata, a member of the family Orchidaceae, is a perennial herbaceous plant used in Chinese medicine. It is a commonly cultivated economic crop in the Yangtze River Basin provinces of China, as its roots are used to treat bleeding and inflammation. In Zhejiang province, Bletilla striata has a planting area of 1400 hectares with a total production of approximately 2.6×106 kg. In October 2021, over 40% of B. striata plants showed severe wilt in a traditional Chinese medicine plantation (ca. 10 ha) in Xianju City, Zhejiang Province, China. In July, leaf curling, crinkling, and leaf-edge browning of the diseased plants were first noticed in the field. Then, necrotic streaks gradually spread to the roots. Stems displayed chlorosis and withering and when they were cut vertically, symptoms such as vascular bundle discoloration, appeared. After October, the individual plants slowly wilted and died, their aboveground parts became filamentous, and the epidermis detached from the corm's fibrous roots. Diseased plants were easily removed as the corm root had fractured. White mycelia were clearly seen in the stem. Three symptomatic leaves and three stems were cut, their surfaces disinfected, and plated on potato dextrose agar (PDA). Six strains were subsequently isolated from all samples. Fungal colonies with white to cream-colored mycelia from all tissues appeared after 3 d of incubation at 26 °C. Pure cultures obtained after monospore isolation were examined for their morphological characteristics. The colonies grew rapidly, were fluffy and appressed, and had cottony white to pale cream coloration. Microconidia were hyaline, oval to reniform, with zero or one-septate (4.0-12.0 × 1.0-5.5 µm), and usually formed on elongated monophialidic conidiogenous cells. Macroconidia were wide, fusiform, or slightly curved with one or three septa (23.0-36.0 × 4.5-7.0 µm). Chlamydospores were spherical and were abundant on carrot agar (CA) medium within 2 wk. Fresh mycelia and conidia that grew at 26 ℃ for 7 d were collected from PDA plates. Next, DNA was extracted using the Ezup Column Fungi Genomic DNA Purification kit (Sangon Biotech, Shanghai, China). We amplified a portion of RNA polymerase II second largest subunit gene (RPB2) using primers 5f2/7cr (O'Donnell et al. 2010), the internal transcribed spacer (ITS) region using primers ITS1F/ITS4 (White et al. 1990), and the partial translation elongation factor-1α gene using primers EF1/ EF2 (O'Donnell et al. 1998) from the genomic DNA and sent the PCR amplicons for sequencing at Tsingke Biotechnology Co., Ltd., Wuhan, China. A BLAST search of the obtained sequences (GenBank accessions OP743920, OP913183, and OP913180) showed 99-100% homology with the respective sequences of the Fusarium solani reference isolate NRRL46702 (O'Donnell et al. 2008). Based on the morphological and molecular characteristics and BLAST search, the fungus was identified as F. solani (Leslie and Summerell 2006). Pathogenicity of the purified F. solani isolate was assessed by inoculateing a F. solani spore suspension of 1×106 conidia/mL (20 mL per seedling) on corm wounds made with a toothpick. Four inoculated and three non-inoculated seedlings (sterilized water as a negative control) were grown in a greenhouse at 26 °C under natural sunlight and covered with plastic bags to maintain humidity for 72 h. After 15 d, leaf browning on leaf edges, new leaf bases, and corm epidermis was observed. Symptoms, similar to those detected in the original sample, developed on the inoculated leaves, whereas the controls remained asymptomatic. Fusarium solani was successfully re-isolated from all four inoculated seedlings, and their identity confirmed by generating partial Tef1 and RPB2 sequences, thereby fulfilling the Koch's postulate. To our knowledge, F. solani has not been previously reported as a pathogen of B. striata.

3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(5): 685-690, 2020 Sep.
Artículo en Zh | MEDLINE | ID: mdl-32975085

RESUMEN

OBJECTIVE: To analyze the epidemiological characteristics of hand, foot and mouth disease (HFMD) in Sichuan Province from 2013 to 2019. To study the correlation between meteorological factors and the incidence of HFMD and construct a prediction model. METHODS: The HMFD surveillance data and meteorological data from 2013 to 2019 in Sichuan Province were collected through the Chinese Center for Disease Control and Prevention and the China Meteorological data Network. Spearman correlation was used to analyze the relationship between HFMD incidence and meteorological factors. Multiple regression model and support vector regression (SVR) model were used to construct HFMD incidence prediction models respectively. RESULTS: A total of 615 840 cases of HFMD and 81 deaths were reported from 2013 to 2019. The average annual incidence rate was 107.31/105, and the mortality rate was 0.16/106. Spearman correlation analysis showed that the monthly incidence rate of HFMD was correlated with monthly average relative humidity (r=0.342), monthly average temperature (r=0.284), monthly average water vapor pressure (r=0.304) and monthly average days of precipitation (r=0.259). The prediction effect of the SVR model (R2=0.836) was better than the multiple regression model (R2=0.375). The SVR model provided a good fit to the monthly incidence of HFMD from 2013 to 2018, and can predict the peak incidence of HFMD in 2019. CONCLUSION: Relative humidity has the greatest influence on the incidence of HFMD. The fitting value of SVR model is in good agreement with the actual value, which is valuable in predicting the incidence of HFMD in Sichuan Province.


Asunto(s)
Enfermedad de Boca, Mano y Pie , China/epidemiología , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Incidencia , Conceptos Meteorológicos , Temperatura
4.
Zhongguo Yi Liao Qi Xie Za Zhi ; 42(5): 380-383, 2018 Sep 30.
Artículo en Zh | MEDLINE | ID: mdl-30358358

RESUMEN

OBJECTIVE: To study the in vitro degradation of oxidized regenerated cellulose absorbable hemostatic products. METHODS: The morphology of the oxidized regenerated cellulose hemostatic products before and after degradation was observed by FTIR and SEM. The degradation products were determined by GPC and HILIC-ELSD. RESULTS: In the initial stage of degradation, there was a great change in morphology. GPC determined its degradation end point was 10 d; it was determined that its degradation products contained glucose (0.13%) and cellobiose (0.17%) and other components. CONCLUSIONS: A method was established for determining the end point of degradation of oxidized regenerated cellulose, which provided a new idea and reference for the study of the degradation end point.


Asunto(s)
Celulosa Oxidada , Hemostáticos , Celulosa
5.
Anal Biochem ; 471: 38-43, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25286306

RESUMEN

A novel immunosensor for α-1-fetoprotein based on dialdehyde cellulose/ionic liquid composite film as a matrix has been developed. Microcrystalline cellulose was activated by sodium metaperiodate to produce dialdehyde cellulose. Antibodies can be immobilized on the electrode by a one-step method through covalent bonding of the aldehyde groups of dialdehyde cellulose with the amino groups of antibodies, in which no additional chemical cross-linking step is required. Moreover, ionic liquid added can improve the conductivity of the sensing interface and, therefore, can enhance the electrochemical signal. In this work, α-1-fetoprotein was detected within the range from 0.1 to 60ngml(-1) with a detection limit of 0.07ngml(-1) (signal/noise=3). The proposed immunosensor had good specificity and reproducibility. It was used to determine real samples with satisfactory results.


Asunto(s)
Anticuerpos Inmovilizados/química , Técnicas Biosensibles/métodos , Celulosa/análogos & derivados , Inmunoensayo/métodos , Líquidos Iónicos/química , alfa-Fetoproteínas/análisis , Animales , Anticuerpos Inmovilizados/inmunología , Celulosa/química , Electroquímica , Electrodos , Humanos , Reproducibilidad de los Resultados , alfa-Fetoproteínas/inmunología
6.
J Chem Phys ; 135(15): 155105, 2011 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-22029339

RESUMEN

Because of the branching arising from partial self-complementarity, long single-stranded (ss) RNA molecules are significantly more compact than linear arrangements (e.g., denatured states) of the same sequence of monomers. To elucidate the dependence of compactness on the nature and extent of branching, we represent ssRNA secondary structures as tree graphs which we treat as ideal branched polymers, and use a theorem of Kramers for evaluating their root-mean-square radius of gyration, ̂R(g)=√R(g)(2). We consider two sets of sequences--random and viral--with nucleotide sequence lengths (N) ranging from 100 to 10,000. The RNAs of icosahedral viruses are shown to be more compact (i.e., to have smaller ̂R(g)) than the random RNAs. For the random sequences we find that ̂R(g) varies as N(1/3). These results are contrasted with the scaling of ̂R(g) for ideal randomly branched polymers (N(1/4)), and with that from recent modeling of (relatively short, N ≤ 161) RNA tertiary structures (N(2/5)).


Asunto(s)
ARN/química , Simulación por Computador , Modelos Químicos , Modelos Moleculares , Conformación de Ácido Nucleico , Polímeros/química
7.
J Arthroplasty ; 26(8): 1251-8.e1-4, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21531114

RESUMEN

Four wound closure techniques for total knee arthroplasty were compared in a prospective, randomized, controlled, institutional review board-approved study with 75 subjects. The study compared tissue adhesives, stapling, and suturing with respect to procedure time and cost, together with functional and clinical outcome. Total knee arthroplasty closure time (capsule to cutaneous) favored staples at 26 s/cm, followed by adhesives (45 and 37 s/cm for 2-octyl and n-butyl-2, respectively) and, finally, subcuticular suturing at 54 s/cm (P < .0007). Reduced procedure time translated into intraoperative cost reduction where closure cost per centimeter was $70, $62, $57, and $75 for 2-octyl, n-butyl-2, staples, and sutures, respectively. No significant differences in infection, dehiscence, cosmesis, general health (SF-12v2 (QualityMetric Inc., Lincoln, RI)), and functional and clinical assessments (range of motion, Knee Society knee score, and pain) were observed.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/cirugía , Suturas , Adhesivos Tisulares , Técnicas de Cierre de Heridas , Anciano , Artralgia/epidemiología , Artroplastia de Reemplazo de Rodilla/economía , Análisis Costo-Beneficio , Humanos , Incidencia , Articulación de la Rodilla/fisiología , Persona de Mediana Edad , Estudios Prospectivos , Rango del Movimiento Articular/fisiología , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Técnicas de Cierre de Heridas/efectos adversos , Técnicas de Cierre de Heridas/economía , Cicatrización de Heridas/fisiología
8.
Water Sci Technol ; 64(9): 1870-5, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22020481

RESUMEN

Aerobic granulation (AG) and membrane bioreactor (MBR) are two promising, novel environmental biotechnological processes that draw interest of researchers working in the area of biological wastewater treatment. Membrane fouling in the combined aerobic granular membrane bioreactor (AGMBR) process and the conventional MBR process was investigated in this work. The irreversible fouling on hollow-fibre membranes in both reactors were observed with the multiple staining and confocal laser scanning microscope technique. Following physical and chemical washing, the external fouling layers were mostly removed. However, the biofilms built up in the interior surface of membrane remained and contributed to the irreversible fouling resistance. AGMBR retained most cells with granules, thereby reducing their penetration through membrane and thus the chance to form internal fouling layer. The internal biofilm layer was principally composed of live cells embedded in a matrix of proteins and polysaccharides, with that on AGMBR denser and thicker than that on MBR. Prevention of development of internal biofilm is essential to reduce irreversible fouling of AGMBR and MBR membranes.


Asunto(s)
Incrustaciones Biológicas , Reactores Biológicos/microbiología , Membranas Artificiales , Aerobiosis , Biopelículas , Análisis de la Demanda Biológica de Oxígeno , Biopolímeros/análisis , Carbono/análisis , Microscopía Confocal , Presión , Factores de Tiempo
9.
World J Clin Cases ; 9(32): 9926-9934, 2021 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-34877332

RESUMEN

BACKGROUND: We report three patients with drug-induced gingiva overgrowth (DIGO) caused by nifedipine, a calcium channel blocker, who were treated and followed up for 1-3 years. We discussed their symptoms, treatment process, treatment prognosis, and follow-up results. CASE SUMMARY: All the patients had a history of nifedipine treatment to control hypertension. Besides nifedipine, Patient 1 was prescribed immunosuppressant cyclosporine A to control nephritis, which is also implicated in GO. Thus, we assumed that a synergistic effect between the drugs contributed to the severity of Patient 1's condition. This condition has been reported to be more pronounced in patients with periodontitis. In the course of treatment, Patients 1 and 2 did not stop or change drugs. After initial periodontal treatment, periodontal surgery, and later periodontal support and better plaque control, their gingival hyperplasia was well managed and controlled. Under the guidance of a physician, Patient 3 replaced her calcium-channel blocker drug with losartan potassium and hydrochlorothiazide tablets. She received initial treatment without surgery, obtaining a good curative effect. CONCLUSION: Patients' compliance, self-plaque control, and professional periodontal therapy have a vital role in treating and preventing the recurrence of DIGO.

10.
J Colloid Interface Sci ; 593: 315-322, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33744540

RESUMEN

In this study, positively charged monomers were grafted onto negatively charged membranes via UV radiation to improve the antifouling/antibiofouling properties of the polymeric membrane and the stability of the modification layer. The surface properties, morphologies, antifouling and antibiofouling properties, and stability of the modified membranes were systematically characterized. Results indicated that the introduction of [2-(methacryloyloxy) ethyl] trimethylammonium chloride (MTAC) monomers onto polyethersulfone (PES)/sulfonated polyethersulfone (SPES) membranes effectively increased the surface hydrophilicity. Meanwhile, the surfaces were neutralized with ~0 mV zeta potential in pH 3-10. Moreover, the formation of a polyampholytic copolymer and the antibacterial ability of MTAC considerably improved the antibiofouling properties of the modified membranes. The MTAC-grafted PES/SPES membranes showed excellent antifouling/antibiofouling properties during the treatment of various types of wastewater, including bovine serum albumin solution, oil/water emulsion, and bacterial suspension. Therefore, this study provides a simple and effective method of constructing stable and antifouling membranes for sustainable water treatment.


Asunto(s)
Incrustaciones Biológicas , Incrustaciones Biológicas/prevención & control , Interacciones Hidrofóbicas e Hidrofílicas , Membranas Artificiales , Albúmina Sérica Bovina , Propiedades de Superficie
11.
J Colloid Interface Sci ; 584: 225-235, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33069021

RESUMEN

To overcome the organic-/bio- fouling of the membrane, a dual-functional ultrafiltration membrane containing quaternary ammonium and zwitterionic polymers via quaternization and surface radical polymerization was designed, and its antifouling and antibacterial behavior was studied. In this work, poly(vinylidene fluoride)/poly(methyl methacrylate-co-dimethylamino-2-ethyl methacrylate) (PVDF/P(MMA-co-DMAEMA)) blend membrane was quaternized by p-chloromethyl styrene (p-CMS), and the double bonds were introduced onto the membrane surface, which further participated in the polymerization of zwitterionic monomers on the membrane surface. The results indicated that the resultant membrane exhibited obviously improved hydrophilicity and weak positive charge (isoelectric point, 7.49). The membrane presented higher flux recovery ratio and lower protein adhesion compared with the pure PVDF membrane. Meanwhile, the membrane showed high-efficiency broad-spectrum antibacterial performance, that is, the bacteria killing efficiency of S. aureus and E. coli reached 98.2% and 97.0%, respectively. Moreover, the membrane effectively inhibited bacterial adhesion, which is important for the long-term antibacterial properties of membrane. This antifouling and antibacterial PVDF membrane may have potential in the long-term filtration process, especially when dealing with microbiologically contaminated water.


Asunto(s)
Compuestos de Amonio , Incrustaciones Biológicas , Antibacterianos/farmacología , Incrustaciones Biológicas/prevención & control , Escherichia coli , Polímeros , Staphylococcus aureus
12.
Nat Commun ; 12(1): 6923, 2021 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-34836947

RESUMEN

Nationwide nonpharmaceutical interventions (NPIs) have been effective at mitigating the spread of the novel coronavirus disease (COVID-19), but their broad impact on other diseases remains under-investigated. Here we report an ecological analysis comparing the incidence of 31 major notifiable infectious diseases in China in 2020 to the average level during 2014-2019, controlling for temporal phases defined by NPI intensity levels. Respiratory diseases and gastrointestinal or enteroviral diseases declined more than sexually transmitted or bloodborne diseases and vector-borne or zoonotic diseases. Early pandemic phases with more stringent NPIs were associated with greater reductions in disease incidence. Non-respiratory diseases, such as hand, foot and mouth disease, rebounded substantially towards the end of the year 2020 as the NPIs were relaxed. Statistical modeling analyses confirm that strong NPIs were associated with a broad mitigation effect on communicable diseases, but resurgence of non-respiratory diseases should be expected when the NPIs, especially restrictions of human movement and gathering, become less stringent.


Asunto(s)
Enfermedades Transmisibles/epidemiología , Notificación de Enfermedades/estadística & datos numéricos , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/transmisión , China/epidemiología , Control de Enfermedades Transmisibles , Enfermedades Transmisibles/clasificación , Enfermedades Transmisibles/transmisión , Humanos , Incidencia , Modelos Estadísticos , SARS-CoV-2
13.
Front Microbiol ; 12: 709849, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34594310

RESUMEN

Human parechoviruses (HPeVs) are important causes of infection in children. However, without a comprehensive and persistent surveillance, the epidemiology and clinical features of HPeV infection remain ambiguous. We performed a hospital-based surveillance study among three groups of pediatric patients with acute respiratory infection (Group 1), acute diarrhea (Group 2), and hand, foot and mouth disease (Group 3) in Chongqing, China, from 2009 to 2015. Among 10,212 tested patients, 707 (6.92%) were positive for HPeV, with the positive rates differing significantly among three groups (Group 1, 3.43%; Group 2, 14.94%; Group 3, 3.55%; P < 0.001). The co-infection with other pathogens was detected in 75.2% (531/707) of HPeV-positive patients. Significant negative interaction between HPeV and Parainfluenza virus (PIV) (P = 0.046, OR = 0.59, 95% CI = 0.34-0.98) and positive interactions between HPeV and Enterovirus (EV) (P = 0.015, OR = 2.28, 95% CI = 1.23-4.73) were identified. Among 707 HPeV-positive patients, 592 (83.73%) were successfully sequenced, and 10 genotypes were identified, with HPeV1 (n = 396), HPeV4 (n = 86), and HPeV3 (n = 46) as the most frequently seen. The proportion of genotypes differed among three groups (P < 0.001), with HPeV1 and HPeV4 overrepresented in Group 2 and HPeV6 overrepresented in Group 3. The spatial patterns of HPeV genotypes disclosed more close clustering of the currently sequenced strains than those from other countries/regions, although they were indeed mixed. Three main genotypes (HPeV1, HPeV3, and HPeV4) had shown distinct seasonal peaks, highlighting a bi-annual cycle of all HpeV and two genotypes (HPeV 1 and HPeV 4) with peaks in odd-numbered years and with peaks in even-numbered years HPeV3. Significantly higher HPeV1 viral loads were associated with severe diarrhea in Group 2 (P = 0.044), while associated with HPeV single infection than HPeV-EV coinfection among HFMD patients (P = 0.001). It's concluded that HPeV infection was correlated with wide clinical spectrum in pediatric patients with a high variety of genotypes determined. Still no clinical significance can be confirmed, which warranted more molecular surveillance in the future.

14.
Mater Sci Eng C Mater Biol Appl ; 113: 110929, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32487376

RESUMEN

The synovial tissues are natural sites of drug delivery for the treatment of rheumatoid arthritis. Our previous study showed that mixed monoterpenes edge-activated PEGylated transfersomes (MMPTs) could significantly enhance the percutaneous absorption of sinomenine (SIN), an anti-inflammation drug. The aim of this study was to investigate the potential of MMPTs for delivery of SIN to the synovial tissues in joint cavities. To this end, conventional liposomes (LPSs) were used as a reference. Transmission electron microscope, constant pressure extrusion method, and differential scanning calorimetry (DSC) were used for physicochemical characterization of the formulations. Confocal laser scanning microscopy (CLSM) and double-sited microdialysis coupled with LC-MS/MS were exploited to study the distribution of MMPTs in different skin layers and pharmacokinetics of SIN in the blood and the joint cavities. The results showed that mixed monoterpenes could significantly enhance the elasticity of MMPTs, evidenced by a decrease in the main transition temperature (Tm) and transition enthalpy (△H). CLSM analyses demonstrated that MMPTs were distributed in deep layers of the skin, indicating that MMPTs might transport SIN through the skin. In contrast, LPSs were confined in the stratum corneum, which deterred SIN from penetrating through the skin. The results from double-sited microdialysis pharmacokinetics showed that in the joint cavities the steady state concentration (Css) and AUC0→t of SIN from MMPTs were 2.1-fold and 2.5-fold of those from LPSs, respectively. In contrast, in the blood the Css and AUC0→t of SIN from MMPTs were about 1/3 of those from LPSs. This study suggested that MMPTs could enhance the delivery of SIN to the joint cavities. A combination of CLSM and double-sited microdialysis could give an insight into the mechanism of transdermal and local drug delivery.


Asunto(s)
Portadores de Fármacos/química , Monoterpenos/química , Morfinanos/química , Polietilenglicoles/química , Administración Tópica , Animales , Área Bajo la Curva , Elasticidad , Articulaciones/metabolismo , Masculino , Microdiálisis , Microscopía Confocal , Morfinanos/sangre , Morfinanos/farmacocinética , Curva ROC , Conejos , Ratas , Ratas Sprague-Dawley , Termodinámica , Temperatura de Transición
15.
J Phys Chem B ; 113(12): 3873-9, 2009 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-19296704

RESUMEN

We consider the force acting on a polymer part of whose length is configurationally confined in a tube and the rest of which is free. This situation arises in many different physical contexts, including a flexible synthetic polymer partially confined in a nanopore and a stiff viral genome partially ejected from its capsid. In both cases the force acting to pull the chain molecule out of its confinement is argued to be constant once a few persistence lengths are "free"/"outside". We present Brownian dynamics simulations that confirm the constancy of the force for different chain lengths and illustrate the dependence of the force on the strength of tube confinement. Experimental results are reported for genome ejection from viral capsids, from which we estimate the pulling force to be a few tenths of a piconewton.


Asunto(s)
Polímeros/química , Simulación por Computador , Modelos Químicos
16.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(3): 248-252, 2019 Jun 01.
Artículo en Zh | MEDLINE | ID: mdl-31218856

RESUMEN

OBJECTIVE: To verify the effect of the mutant gene vps4b on the expression of tooth development-related proteins, dentin sialophosphoprotein (DSPP) and collagenⅠ (COL-Ⅰ). METHODS: Paraffin tissue sections of the first molar tooth germ were obtained from the heads of fetal mice at the embryonic stages of 13.5, 14.5, and 16.5 days and from the mandibles of larvae aged 2.5 and 7 days after birth. The immunohistochemical method was used to detect the expression and location of DSPP and COL-Ⅰ in wild-type mouse and vps4b knockout mouse. RESULTS: DSPP and COL-Ⅰ were not found in the bud and cap stages of wild-type mouse molar germ. In the bell stage, DSPP was positively expressed in the inner enamel epithelium and dental papilla, whereas COL-Ⅰ was strongly expressed in the dental papilla and dental follicle. During the secretory and mineralized periods, DSPP and COL-Ⅰ were intensely observed in ameloblasts, odontoblasts, and dental follicles, but COL-Ⅰ was also expressed in the dental papilla. After vps4b gene knockout, DSPP was not expressed in the dental papilla of the bell stage and in the dental papilla and dental follicle of the secretory phase. The expression position of COL-Ⅰ in the bell and mineralization phase was consistent with that in the wild-type mice. Moreover, the expression of COL-Ⅰ in the dental papilla changed in the secretory stage. CONCLUSIONS: Gene vps4b plays a significant role in the development of tooth germ. The expression of DSPP and COL-Ⅰ may be controlled by gene vps4b and regulates the development of tooth dentin and cementum together with vps4b.


Asunto(s)
ATPasas Asociadas con Actividades Celulares Diversas , Complejos de Clasificación Endosomal Requeridos para el Transporte , Proteínas de la Matriz Extracelular , Fosfoproteínas , Sialoglicoproteínas , ATPasas Asociadas con Actividades Celulares Diversas/genética , Animales , Colágeno/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Proteínas de la Matriz Extracelular/metabolismo , Ratones , Ratones Noqueados , Diente Molar , Odontoblastos , Fosfoproteínas/metabolismo , Sialoglicoproteínas/metabolismo , Germen Dentario
17.
Biomed Pharmacother ; 118: 109305, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31545264

RESUMEN

Foot-and-mouth disease virus (FMDV) is an important pathogen that affects livestock breeding and causes huge economic losses worldwide. Currently, the development of antiviral agents to combat FMDV infection at the early stages is being explored. As viral replication critically depends on the host for nucleoside supply, host enzymes involved in nucleotides biosynthesis may represent potential targets for the development of antiviral agents. In the present study, the effects of IMP dehydrogenase (AVN-944 and mycophenolate mofetil) and dihydroorotate dehydrogenase (teriflunomide) inhibitors were evaluated both in vitro and in vivo. The results revealed that these compounds were effective in suppressing FMDV (O/MY98/BY/2010 and A/GD/MM/2013) infection. With regard to the antiviral mechanism, time-of-addition experiments revealed that these compounds were effective when added at the early stages of viral lifecycle (0-8 h post infection). However, exogenous guanosine/uridine eliminated the antiviral activity of these compounds. Importantly, treatment AVN-944 and teriflunomide significantly improved the survival of mice that were subcutaneously treated with FMDV. Together, the results of the present study indicate the broad-spectrum activities of anti-FMDV agents targeting IMP dehydrogenase or dihydroorotate dehydrogenase, which could be useful in developing strategies to prevent FMD.


Asunto(s)
Antivirales/farmacología , Inhibidores Enzimáticos/farmacología , Virus de la Fiebre Aftosa/fisiología , IMP Deshidrogenasa/antagonistas & inhibidores , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/antagonistas & inhibidores , Animales , Antivirales/química , Antivirales/uso terapéutico , Muerte Celular , Línea Celular , Dihidroorotato Deshidrogenasa , Inhibidores Enzimáticos/química , Fiebre Aftosa/tratamiento farmacológico , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/efectos de los fármacos , Guanosina/farmacología , IMP Deshidrogenasa/metabolismo , Ratones Endogámicos BALB C , Miocardio/patología , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/metabolismo , Uridina/farmacología
18.
Lancet Public Health ; 3(8): e385-e394, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30033200

RESUMEN

BACKGROUND: Transmission of infection through international travel is a growing health issue, and the frequency of imported infection is increasing in China. We aimed to quantify the total number of infections imported into mainland China by arriving travellers. METHODS: We actively surveyed arriving travellers at all 272 international entry-exit ports in mainland China. Suspected cases were detected through fever screening, medical inspection, self-declaration, and reporting by on-board staff. Participants completed a standardised questionnaire with questions about demographics, their travel itinerary (including detailed information about all countries or regions visited), and clinical manifestations. Nasopharyngeal swabs, sputum samples, faecal samples, vomitus, blood, and serum were collected as appropriate for diagnoses. Diagnosis was made by specific laboratory tests according to the national technical guidelines. Infections were classified as respiratory, gastrointestinal, vector-borne, blood-transmitted and sex-transmitted, or mucocutaneous. We divided arriving travellers into two groups: travellers coming from countries other than China, and travellers coming from Hong Kong, Macau, and Taiwan. We integrated surveillance data for 2014-16, calculated incidences of travel-related infections, and compared the frequency of infections among subgroups. FINDINGS: Between Jan 1, 2014, and Dec 31, 2016, 22 797 cases were identified among 805 993 392 arriving travellers-an overall incidence of 28·3 per million. 45 pathogens were detected in participants: 18 respiratory (19 662 cases), ten gastrointestinal (189 cases), seven vector-borne (831 cases), seven blood-transmitted and sex-transmitted (1531 cases), and three mucocutaneous (584 cases). Both the overall number and incidence of infection were more than five times higher in 2016 than in 2014. Case numbers and incidences also varied substantially by province, autonomous region, and municipality. Overall, 17 643 (77%) infections were detected by fever screening, but 753 (49%) blood-transmitted and sex-transmitted infections were identified through medical inspection. 14 305 (73%) cases of respiratory infection and 96 (51%) of gastrointestinal infections were in tourists. Tuberculosis, hepatitis A virus, vector-borne, and blood-transmitted and sex-transmitted infections were common among Chinese labourers who worked abroad. Dengue and malaria were most commonly diagnosed in travellers arriving from Africa. 12 126 (93%) of the 12 985 cases arriving from Hong Kong, Macau, or Taiwan were respiratory infections. Hand, foot, and mouth disease accounted for 2·90% of infections in travellers from Hong Kong, Macau, or Taiwan and 0·31% of infections in international travellers. INTERPRETATION: This report is the first to characterise the profile of travel-related infections among arriving travellers in mainland China. Our findings should increase public awareness of the potential risk of imported infections, and help health-care providers to make evidence-based health recommendations to travellers. FUNDING: The Natural Science Foundation of China.


Asunto(s)
Vigilancia de la Población , Enfermedad Relacionada con los Viajes , Adolescente , Adulto , Niño , China/epidemiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Adulto Joven
19.
PLoS One ; 13(6): e0197188, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29856735

RESUMEN

Sugarcane bagasse was refined into cellulose, hemicellulose, and lignin using an ethanol-based organosolv technique. The hydrothermal carbonization (HTC) reactions were applied for bagasse and its two components cellulose and lignin. Based on GC-MS analysis, 32 (13+19) organic byproducts were derived from cellulose and lignin, more than the 22 byproducts from bagasse. Particularly, more valuable catechol products were obtained from lignin with 56.8% share in the total GC-MS integral area, much higher than the 2.263% share in the GC-MS integral areas of bagasse. The organic byproducts from lignin make up more than half of the total mass of lignin, indicating that lignin is a chemical treasure storage. In general, bio-refinery and HTC are two effective techniques for the valorization of bagasse and other biomass materials from agriculture and forest industry. HTC could convert the inferior biomass to superior biofuel with higher energy quantity of combustion, at the same time many valuable organic byproducts are produced. Bio-refinery could promote the HTC reaction of biomass more effective. With the help of bio-refinery and HTC, bagasse and other biomass materials are not only the sustainable energy resource, but also the renewable and environment friendly chemical materials, the best alternatives for petroleum, coal and natural gas.


Asunto(s)
Biomasa , Celulosa/química , Lignina/química , Saccharum/química
20.
Environ Pollut ; 149(1): 125-30, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17291645

RESUMEN

A novel sand-fixing agent-poly(aspartic acid) and its composites were synthesized to improve sand particles compressive strength and anti-wind erosion properties. The relationship between the concentration of sand-fixing agent and the sand-fixing properties was studied by three kinds of aging tests. Some composites were choose to improve the sand-fixing property and the composition of 40% xanthan gum and 60% ethyl cellulose were chosen to compare sand-fixing property with lignosulfonate. The results showed that the sand-fixing and water-retaining properties of xanthan gum and ethyl cellulose composites were better than that of lignosulfonate. The biodegradability experiment showed that the PASP and its composites were environment-friendly products and the field test showed that the PASP composites could improve wind erosion disturbance.


Asunto(s)
Ácido Aspártico/síntesis química , Resinas Compuestas/síntesis química , Conservación de los Recursos Naturales/métodos , Dióxido de Silicio , China , Clima , Fuerza Compresiva , Ensayo de Materiales/métodos , Resistencia a la Tracción , Tiempo , Viento
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