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1.
J Am Chem Soc ; 146(7): 4942-4957, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38326715

RESUMO

Four-membered carbocycles are fundamental substructures in bioactive molecules and approved drugs and serve as irreplaceable building blocks in organic synthesis. However, developing efficient protocols furnishing diversified four-membered ring compounds in a highly regio-, diastereo-, and enantioselective fashion remains challenging but very desirable. Here, we report the unprecedented asymmetric transfer hydrogenation of cyclobutenediones. The reaction can selectively afford three types of four-membered products in high yields with high stereoselectivities, and the highly functionalized products enable a series of further transformations to form more diversified four-membered compounds. Asymmetric synthesis of di-, tri-, and tetrasubstituted bioactive molecules has also been achieved. Systematic mechanistic studies and theoretical calculations have revealed the origin of the regioselectivity, the key hydrogenation transition state models, and the sequence of the double and triple hydrogenation processes. The work provides a new choice for the catalytic asymmetric synthesis of cyclobutanes and related structures and demonstrates the robustness of asymmetric transfer hydrogenation in the accurate selectivity control of highly functionalized substrates.

2.
Environ Res ; 251(Pt 1): 118587, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38437903

RESUMO

Nitrate (NO3-) pollution in irrigation canals is of great concern because it threatens canal water use; however, little is known about it at present. Herein, a combination of positive matrix factorization (PMF), isotope tracers, and Mixing Stable Isotope Analysis in R (MixSIAR) was developed to identify anthropogenic impacts and quantitative sources of NO3- in a rural-urban canal in China. The NO3- concentration (0.99-1.93 mg/L) of canal water increased along the flow direction and was higher than the internationally recognized eutrophication risk value in autumn and spring. The inputs of the Fuhe River, NH4+ fertilizer, soil nitrogen, manure & sewage, and rainfall were the main driving factors of canal water NO3- based on principal component analysis and PMF, which was supported by evidence from δ15N/δ18O-NO3-. According to the chemical and isotopic analyses, nitrogen transformation was weak, highlighting the potential of δ15N/δ18O-NO3- to trace NO3- sources in canal water. The MixSIAR and PMF results with a <15% divergence emphasized the predominance of the Fuhe River (contributing >50%) and anthropogenic impacts (NH4+ fertilizer plus manure & sewage, >37%) on NO3- in the entire canal, reflecting the effectiveness of the model analysis. According to the MixSIAR model, (1) higher NO3- concentration in canal water was caused by the general enhancement of human activities in spring and (2) NO3- source contributions were associated with land-use patterns. The high contributions of NH4+ fertilizer and manure & sewage showed inverse spatial variations, suggesting the necessity of reducing excessive fertilizer use in the agricultural area and controlling blind wastewater release in the urban area. These findings provide valuable insights into NO3- dynamics and fate for sustainable management of canal water resources. Nevertheless, long-term chemical and isotopic monitoring with alternative modeling should be strengthened for the accurate evaluation of canal NO3- pollution in future studies.


Assuntos
Monitoramento Ambiental , Nitratos , Isótopos de Nitrogênio , Poluentes Químicos da Água , Nitratos/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , China , Isótopos de Nitrogênio/análise , Isótopos de Oxigênio/análise , Fertilizantes/análise , Rios/química , Cidades , Irrigação Agrícola
3.
Gerontology ; 70(2): 155-164, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38008089

RESUMO

INTRODUCTION: Pneumonia is a common and devastating complication following hip fracture surgery in older patients. Time to surgery is a potentially modifiable factor associated with improved prognosis, and we aim to quantify the time-effect relationship between time to surgery and in-hospital postoperative pneumonia (IHPOP) and identify the effect of delayed surgery on the risk of IHPOP. METHODS: We analyzed clinical data of older hip fracture patients (≥60 years) undergoing surgical treatments at a tertiary referral trauma center between 2015 and 2020. Restricted cubic spline (RCS) was used to fit the time-effect relationship between time to surgery and IHPOP. Based on the results of RCS, we divided patients into two groups of "early surgery" and "delayed surgery." A 1:1 propensity score matching (PSM) analysis and multivariate conditional logistic regression analysis were performed to minimize the selection bias and determine the association magnitude. Subgroup analysis was conducted to assess potential interaction effects between delayed surgery and common risk factors for IHPOP. RESULTS: 3,118 eligible patients were included. The RCS curve showed an inverse S-shape trend and the relative risk of IHPOP decreased in the range of days 2-3 and increased on day 1 and day 3 or more post-injury, with the lowest point on day 3. PSM yielded 1,870 matched patients and delayed surgery (>3 days) was identified to be independently associated with IHPOP (relative ratio, 1.66; 95% confidence interval, 1.12-2.46; p value, 0.011). We observed positive interaction effects between delayed surgery and age of 80 years or more, female gender, COPD, heart disease, ASA score ≥3, anemia, and hypoproteinemia. CONCLUSION: The relative risk of IHPOP decreased in the range of 2-3 days and increased on day 1 and day 3 or more post-injury. Delayed surgery (>3 days) was identified to be independently associated with a 1.66-fold increased risk of IHPOP.


Assuntos
Fraturas do Quadril , Pneumonia , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fraturas do Quadril/complicações , Fraturas do Quadril/cirurgia , Fatores de Risco , Pneumonia/etiologia , Pneumonia/complicações , Hospitais , Estudos Retrospectivos
4.
Anim Biotechnol ; 35(1): 2337760, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38656923

RESUMO

Although the knee joint (KNJ) and temporomandibular joint (TMJ) all belong to the synovial joint, there are many differences in developmental origin, joint structure and articular cartilage type. Studies of joint development in embryos have been performed, mainly using poultry and rodents. However, KNJ and TMJ in poultry and rodents differ from those in humans in several ways. Very little work has been done on the embryonic development of KNJ and TMJ in large mammals. Several studies have shown that pigs are ideal animals for embryonic development research. Embryonic day 30 (E30), E35, E45, E55, E75, E90, Postnatal day 0 (P0) and Postnatal day 30 (P30) embryos/fetuses from the pigs were used for this study. The results showed that KNJ develops earlier than TMJ. Only one mesenchymal condensate of KNJ is formed on E30, while two mesenchymal condensates of TMJ are present on E35. All structures of KNJ and TMJ were formed on E45. The growth plate of KNJ begins to develop on E45 and becomes more pronounced from E55 to P30. From E75 to E90, more and more vascular-rich cartilage canals form in the cartilage regions of both joints. The cartilaginous canal of the TMJ divides the condyle into sections along the longitudinal axis of the condyle. This arrangement of cartilaginous canal was not found in the KNJ. The chondrification of KNJ precedes that of TMJ. Ossification of the knee condyle occurs gradually from the middle to the periphery, while that of the TMJ occurs gradually from the base of the mandibular condyle. In the KNJ, the ossification of the articular condyle is evident from P0 to P30, and the growth plate is completely formed on P30. In the TMJ, the cartilage layer of condyle becomes thinner from P0 to P30. There is no growth plate formation in TMJ during its entire development. There is no growth plate formation in the TMJ throughout its development. The condyle may be the developmental center of the TMJ. The chondrocytes and hypertrophic chondrocytes of the growth plate are densely arranged. The condylar chondrocytes of TMJ are scattered, while the hypertrophic chondrocytes are arranged. Embryonic development of KNJ and TMJ in pigs is an important bridge for translating the results of rodent studies to medical applications.


Assuntos
Articulação do Joelho , Articulação Temporomandibular , Animais , Suínos/embriologia , Articulação Temporomandibular/embriologia , Articulação Temporomandibular/crescimento & desenvolvimento , Articulação do Joelho/embriologia , Articulação do Joelho/crescimento & desenvolvimento , Cartilagem Articular/embriologia , Cartilagem Articular/crescimento & desenvolvimento , Feminino , Desenvolvimento Embrionário/fisiologia , Embrião de Mamíferos
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(10): 1145-1148, 2022 Oct 10.
Artigo em Zh | MEDLINE | ID: mdl-36184101

RESUMO

OBJECTIVE: To explore the clinical characteristics of a child with early-onset infantile epileptic encephalopathy type 8 associated with synonymous variant of ARHGEF9 gene. METHODS: Clinical data of the patient was summarized. The child and his parents were subjected to trio-whole exome sequencing. RESULTS: The child has presented with global developmental delay, epilepsy, impulsive behavior, hypersensitivity to sound, and mental retardation. He was found to harbor a de novo synonymous variant c.741C>T (p.Cys247Cys) of the ARHGEF9 gene. RNA splicing analysis confirmed that the variant has led to abnormal splicing of exon 5, resulting in a 55-bp deletion. CONCLUSION: The clinical features of ARHGEF9 gene-related early-onset infantile epileptic encephalopathy type 8 includes mental and motor developmental delay, epilepsy, auditory allergy, and hyperactivity impulsivity. For synonymous variant, in vitro study and transcriptional experiment may be carried out to evaluate its functional and splicing effect. Above finding has enriched the phenotypic and genotypic spectrum of the ARHGEF9 gene.


Assuntos
Epilepsia , Deficiência Intelectual , Espasmos Infantis , Criança , Epilepsia/genética , Éxons , Humanos , Lactente , Deficiência Intelectual/genética , Masculino , Fatores de Troca de Nucleotídeo Guanina Rho/genética , Espasmos Infantis/genética
6.
Zhongguo Zhong Yao Za Zhi ; 47(1): 265-270, 2022 Jan.
Artigo em Zh | MEDLINE | ID: mdl-35178933

RESUMO

It was pointed out in Opinions on Promoting the Inheritance, Innovation and Development of Traditional Chinese Medicine issued by the State Council in 2019 that 100 varieties of traditional Chinese medicine(TCM) with unique curative effects should be screened out within about three years. Due to the multi-component and multi-target mechanisms of TCM varieties, it is difficult to directly and simply evaluate their multi-dimensional clinical value using methods applicable to chemical or biological agents. The heterogeneity of outcomes for similar TCM makes it difficult to determine the advantages of similar products. The fuzzy comprehensive evaluation method that is developed on the basis of core outcome set and fuzzy mathematics for clinical efficacy evaluation of TCM may solve these problems. This study developed a fuzzy comprehensive evaluation model for the clinical efficacy evaluation of Chinese patent me-dicines for coronary heart disease and angina pectoris, and selected the previous normative studies with complete or incomplete data for verifying the model application. The results showed that original studies with complete data failed to evaluate and compare the comprehensive efficacy of different interventions. The original research only mentioned the advantages and disadvantages of different interventions in different aspects. The comprehensive clinical efficacy of three different interventions obtained through fuzzy comprehensive evaluation was all graded as level Ⅱ. The original research with incomplete data drew the same conclusions as the fuzzy comprehensive evaluation, and the results of fuzzy comprehensive evaluation can provide more comprehensive information. Therefore, the fuzzy comprehensive evaluation shows the products with overall advantages of clinical efficacy, which may become a feasible method for the screening of TCM.


Assuntos
Doença das Coronárias , Medicamentos de Ervas Chinesas , Angina Pectoris , Doença das Coronárias/diagnóstico , Doença das Coronárias/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Medicina Tradicional Chinesa , Resultado do Tratamento
7.
Surg Endosc ; 35(12): 6532-6538, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33185766

RESUMO

BACKGROUND: This study was aimed to develop a computer-aided diagnosis (CAD) system with deep-learning technique and to validate its efficiency on detecting the four categories of lesions such as polyps, advanced cancer, erosion/ulcer and varices at endoscopy. METHODS: A deep convolutional neural network (CNN) that consists of more than 50 layers were trained with a big dataset containing 327,121 white light images (WLI) of endoscopy from 117,005 cases collected from 2012 to 2017. Two CAD models were developed using images with or without annotation of the training dataset. The efficiency of the CAD system detecting the four categories of lesions was validated by another dataset containing consecutive cases from 2018 to 2019. RESULTS: A total of 1734 cases with 33,959 images were included in the validation datasets which containing lesions of polyps 1265, advanced cancer 500, erosion/ulcer 486, and varices 248. The CAD system developed in this study may detect polyps, advanced cancer, erosion/ulcer and varices as abnormality with the sensitivity of 88.3% and specificity of 90.3%, respectively, in 0.05 s. The training datasets with annotation may enhance either sensitivity or specificity about 20%, p = 0.000. The sensitivities and specificities for polyps, advanced cancer, erosion/ulcer and varices reached about 90%, respectively. The detect efficiency for the four categories of lesions reached to 89.7%. CONCLUSION: The CAD model for detection of multiple lesions in gastrointestinal lumen would be potentially developed into a double check along with real-time assessment and interpretation of the findings encountered by the endoscopists and may be a benefit to reduce the events of missing lesions.


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Endoscopia Gastrointestinal , Trato Gastrointestinal , Humanos , Projetos Piloto
8.
Mycopathologia ; 186(6): 893-895, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34455552

RESUMO

PURPOSE: To report a case of keratomycosis caused by a very rare pathogen, Myrothecium verrucaria. METHODS: This is a case report. A 53-year-old man complaint of left eye redness, irritation, intermittent pain after ashes entered his left eye. The patient was examined by slit lamp, anterior segment OCT and in vivo confocal microscopy. The HRT III-RCM image showed massive interlocking white thin lines in the cornea stroma. Corneal scrapings were collected for pathogen culture and PCR test. M. verrucaria was isolated and identified. RESULTS: Hourly topical natamycin (5%) and voriconazole (10 mg/ml) was given as well as intravenous fluconazole (200 mg per day). Treatment was continued with oral itraconazole, 200 mg/day, topical natamycin (5%), 4 times/day, and pranoprofen, 4 times/day. The therapy was tapered off over one and half a month. The cornea lesion healed with scar formation two months later. CONCLUSIONS: This is the first case report of M. verrucaria keratomycosis in China. We are the first to show the characteristic of M. verrucaria on cornea with In vivo confocal microscopy. A combination treatment of tropical natamycin, voriconazole and systemic fluconazole was effective in the treatment of M. verrucaria.


Assuntos
Infecções Oculares Fúngicas , Ceratite , Antifúngicos/uso terapêutico , Infecções Oculares Fúngicas/diagnóstico , Infecções Oculares Fúngicas/tratamento farmacológico , Humanos , Hypocreales , Ceratite/diagnóstico , Ceratite/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Natamicina , Voriconazol
9.
Int Ophthalmol ; 41(4): 1291-1299, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33389425

RESUMO

PURPOSE: To evaluate the performance of an AI-based diabetic retinopathy (DR) grading model in real-world community clinical setting. METHODS: Participants with diabetes on record in the chosen community were recruited by health care staffs in a primary clinic of Zhengzhou city, China. Retinal images were prospectively collected during December 2018 and April 2019 based on intent-to-screen principle. A pre-validated AI system based on deep learning algorithm was deployed to screen DR graded according to the International Clinical Diabetic Retinopathy scale. Kappa value of DR severity, the sensitivity, specificity of detecting referable DR (RDR) and any DR were generated based on the standard of the majority manual grading decision of a retina specialist panel. RESULTS: Of the 193 eligible participants, 173 (89.6%) were readable with at least one eye image. Mean [SD] age was 69.3 (9.0) years old. Total of 321 eyes (83.2%) were graded both by AI and the specialist panel. The κ value in eye image grading was 0.715. The sensitivity, specificity and area under curve for detection of RDR were 84.6% (95% CI: 54.6- 98.1%), 98.0% (95% CI: 94.3-99.6%) and 0.913 (95% CI: 0.797-1.000), respectively. For detection of any DR, the upper indicators were 90.0% (95% CI: 68.3-98.8), 96.6% (95% CI: 92.1-98.9) and 0.933 (95% CI: 0.933-1.000), respectively. CONCLUSION: The AI system showed relatively good consistency with ophthalmologist diagnosis in DR grading, high specificity and acceptable sensitivity for identifying RDR and any DR. TRANSLATIONAL RELEVANCE: It is feasible to apply AI-based DR screening in community. PRECIS: Deployed in community real-world clinic setting, AI-based DR screening system showed high specificity and acceptable sensitivity in identifying RDR and any DR. Good DR diagnostic consistency was found between AI and manual grading. These prospective evidences were essential for regulatory approval.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Idoso , Inteligência Artificial , China/epidemiologia , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Humanos , Programas de Rastreamento , Estudos Prospectivos
10.
Appl Opt ; 59(12): 3619-3623, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32400486

RESUMO

Serious edge effects of potassium dihydrogen phosphate (${{\rm KH}_2}{{\rm PO}_4}$KH2PO4, KDP) manufactured using single-point diamond turning (SPDT) often result in disqualification of the transmittance wavefront for high-power laser systems. In this paper, based on the theoretical analysis of sucker hole configuration and the pressure distribution law under the vacuum chuck condition of crystal elements, the influence of sucker hole configuration on the transmittance wavefront root-mean-square gradient (GRMS) is verified through fly-cutting experiments. By adopting the newly designed vacuum chuck, the vacuum-chucking quality is effectively improved, and the edge effect is accordingly suppressed in the SPDT. Moreover, the accuracy of the transmittance wavefront GRMS has an improvement of about 25% under the same processing parameters.

11.
Chemistry ; 24(36): 8922-8940, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29411433

RESUMO

Iron carbides and nitrides have aroused great interest in researchers, due to their excellent magnetic properties, good machinability and the particular catalytic activity. Based on these advantages, iron carbides and nitrides can be applied in various areas such as magnetic materials, biomedical, photo- and electrocatalysis. In contrast to their simple elemental composition, the synthesis of iron carbides and nitrides still has great challenges, particularly at the nanoscale, but it is usually beneficial to improve performance in corresponding applications. In this review, we introduce the investigations about iron carbides and nitrides, concerning their structure, synthesis strategy and various applications from magnetism to the catalysis. Furthermore, the future prospects are also discussed briefly.

12.
Chemistry ; 23(69): 17592-17597, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-28948671

RESUMO

A new and simple method to fabricate magnetic Fe4 N/Fe3 C samples is reported. Meanwhile, pure phase iron carbides (θ-Fe3 C and χ-Fe5 C2 ) were obtained by controlling experimental conditions. The structures, magnetic properties, and morphology of the samples were investigated according to the generalized analysis of X-ray diffraction, X-ray photoelectron spectroscopy, as well as transmission electron microscopy and vibrating sample magnetometry. The magnetic properties measurement revealed the remarkable magnetic properties of the samples at 2 and 300 K. The application of the prepared samples as catalysts for oxygen evolution reaction was also investigated in alkaline solution. This simple and convenient route provides a new path to fabricate other metal nitrides and carbides.

13.
Nanotechnology ; 28(26): 265204, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28498823

RESUMO

Quantum dots (QDs) have been developed as one of the most promising light-converting materials for white light-emitting diodes (LEDs). In current QD-based LED packaging structures, composites of QDs and polymers are used as light-converting layers. However, the ultralow thermal conductivity of such composites seriously hinders the dissipation of QD-generating heat. In this paper, we demonstrate a method to enhance the thermal dissipation of QD-polymer composites through electrospinning polymer nanofibers. QD-polymer films embedded by electrospun nanofibers were prepared. Benefitting from aligned polymer chains in the electrospun nanofibers, the through-panel and in-panel thermal conductivities of the proposed QD-polymer film increased by 39.9% and 423.1%, respectively, compared to traditional QD-polymer film. The proposed and traditional QD-polymer films were both packaged on chip on board (CoB) LEDs for experimental comparison. Compared to traditional QD-polymer film, the luminous flux and luminous efficiency of the LEDs were increased by up to 51.8% and 42.9% by the proposed QD-polymer film under a current of 800 mA, respectively. With an increase in the driving current from 20-800 mA, the correlated color temperature (CCT) variation decreased by 72.7%. The maximum temperatures in the QD-polymer films were reduced from 419 K-411 K under a driving current of 200 mA.

14.
Chemistry ; 22(14): 4863-9, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-26934176

RESUMO

A series of Fe3C/C-Nx nanoparticles (NPs) with different nitrogen content are prepared by a simple one-pot route. In the synthetic procedure, aniline and acetonitrile are simultaneously used as the carbon and nitrogen source. The effect of calcination temperature on the structural and functional properties of the materials is investigated. Magnetic measurement shows that the sample prepared at 800 °C (Fe3 C/C-N800 NPs) possesses the highest Ms value of 77.2 emu g(-1). On testing as oxygen reduction reaction (ORR) catalysts, the sample prepared at 750 °C (Fe3C/C-N750 NPs) shows the best ORR performance among the series, with a more positive onset potential (+0.99 V vs. RHE), higher selectivity (number of electron transfer n≈3.93), longer durability, and stronger tolerance against methanol crossover than commercial Pt/C catalysts in a 0.1 m KOH solution. Moreover, in acidic solution, the excellent ORR activity and stability are also exhibited.

15.
Phys Chem Chem Phys ; 17(44): 29824-33, 2015 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-26487093

RESUMO

A thin nanoslice structured WS2@reduced graphene oxide (rGO) composite was successfully fabricated by a facile hydrothermal synthesis method. The layered structure and morphology of the composite were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The WS2@rGO composite structure demonstrated significantly enhanced rate capability performance in comparison with pristine WS2 when used as an anode material for lithium-ion batteries (LIBs). The composite demonstrated a capacity of 565 mA h g(-1) after 100 cycles when cycled at 0.1 A g(-1) and it could still deliver a stable capacity of about 337 mA h g(-1) at 2 A g(-1). Electrochemical impedance spectroscopy (EIS) measurement showed that the synergistic effect between WS2 and rGO could remarkably reduce the contact resistance and improve the corresponding electrochemical performances. In order to analyze and interpret the corresponding results from a theoretically sound perspective, first principles calculations was further performed to investigate the corresponding inner mechanisms of pristine WS2 and WS2@graphene composite. The nudged elastic band (NEB) method was used to investigate the diffusion properties of Li in the different structures. Molecular dynamics (MD) simulation and Young's modulus calculation were further employed to explore the stability and mechanical properties of the two structures for the first time. These new perspectives pave the way for the design and fabrication of graphene-TMDs based composites as the next generation of LIB anode materials with high power density and cycling stability.

16.
Zhongguo Zhong Yao Za Zhi ; 40(10): 2050-3, 2015 May.
Artigo em Zh | MEDLINE | ID: mdl-26390672

RESUMO

To learn about the economic studies on traditional Chinese medicines in domestic literatures, in order to analyze the current economic assessment of traditional Chinese medicines and explore the existing problems. Efforts were made to search CNKI, VIP, Wanfang database and CBM by computer and include all literatures about economic assessment of traditional Chinese medicines published on professional domestic journals in the systematic assessment and quality evaluation. Finally, 50 articles were included in the study, and the systematic assessment and quality evaluation were made for them in terms of titles, year, authors' identity, expense source, disease type, study perspective, study design type, study target, study target source, time limit, cost calculation, effect indicator, analytical technique and sensitivity analysis. The finally quality score was 0.74, which is very low. The results of the study showed insufficient studies on economics of traditional Chinese medicines, short study duration and simple evaluation methods, which will be solved through unremitting efforts in the future.


Assuntos
Tratamento Farmacológico/economia , Medicina Tradicional Chinesa/economia , Publicações/economia , Custos e Análise de Custo , Bases de Dados Factuais/economia , Medicamentos de Ervas Chinesas/economia , Medicamentos de Ervas Chinesas/uso terapêutico , Estudos de Avaliação como Assunto
17.
Zhongguo Zhong Yao Za Zhi ; 40(18): 3693-6, 2015 Sep.
Artigo em Zh | MEDLINE | ID: mdl-26983223

RESUMO

The safety of Chinese patent medicine has become a focus of social. It is necessary to carry out work on post-marketing clinical safety evaluation for Chinese patent medicine. However, there have no criterions to guide the related research, it is urgent to set up a model and method to guide the practice for related research. According to a series of clinical research, we put forward some views, which contained clear and definite the objective and content of clinical safety evaluation, the work flow should be determined, make a list of items for safety evaluation project, and put forward the three level classification of risk control. We set up a model of post-marketing clinical safety evaluation for Chinese patent medicine. Based this model, the list of items can be used for ranking medicine risks, and then take steps for different risks, aims to lower the app:ds:risksrisk level. At last, the medicine can be managed by five steps in sequence. The five steps are, collect risk signal, risk recognition, risk assessment, risk management, and aftereffect assessment. We hope to provide new ideas for the future research.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Medicamentos de Ervas Chinesas/efeitos adversos , Medicina Herbária/legislação & jurisprudência , Vigilância de Produtos Comercializados , Ensaios Clínicos como Assunto , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/economia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Herbária/economia , Humanos , Patentes como Assunto , Controle de Qualidade
18.
Arch Virol ; 159(11): 3063-70, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24938486

RESUMO

Four novel double-stranded RNA molecules, named dsRNA 1 (5124 bp), dsRNA 2(1711 bp), dsRNA 3 (1423 bp) and dsRNA 4 (855 bp), were detected in strain HNHS-1 of Ustilaginoidea virens, the causal agent of rice false smut disease. Sequence analysis showed that the dsRNA1 contains two overlapping open reading frames (ORF) potentially encoding proteins with modest levels of sequence similarity to the coat protein (CP) and putative RNA-dependent RNA polymerase (RdRp), respectively, of viruses of the family Totiviridae. The deduced gene product of the ORF encoded by dsRNA2 is homologous to putative RdRp of viruses in the family Partitiviridae; the ORF encoded by dsRNA3 shares some similarity to a hypothetical protein with unknown function. It is noteworthy that the dsRNA4 lacked integrated ORFs. Isomeric viral particles of about 40 nm in diameter were observed by transmission electron microscopy in a mycelium tissue preparation of strain HNHS-1-R1, a single-spore subculture of strain HNHS-1 containing only the dsRNA1 segment. Phylogenetic analysis and examination of the organization of the two putative RdRp sequences both indicated that there are at least two novel virus species present in strain HNHS-1. We named the two novel viruses Ustilaginoidea virens RNA virus 2 and Ustilaginoidea virens partitivirus 4, respectively.


Assuntos
Hypocreales/virologia , Oryza/microbiologia , Totiviridae/isolamento & purificação , Sequência de Aminoácidos , Coinfecção/microbiologia , Coinfecção/virologia , Genoma Viral , Dados de Sequência Molecular , Fases de Leitura Aberta , Oryza/virologia , Filogenia , Doenças das Plantas/microbiologia , Doenças das Plantas/virologia , Alinhamento de Sequência , Totiviridae/classificação , Totiviridae/genética
19.
Virus Genes ; 48(3): 570-3, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24578166

RESUMO

Ustilaginoidea virens is the causal agent of false smut disease of rice. The dsRNA-Ls from a U. virens strain of Uv0901 containing three dsRNA bands were separated and sequenced. The dsRNA-Ls, with molecular weight of 5 kbp, were demonstrated to be two dsRNA segments referenced as dsRNA-L1 and dsRNA-L2. The two dsRNAs each contained two overlapped open reading frames, and showed significant similarity to those of capsid protein and RNA-directed RNA polymerase, respectively, of members of the family Totiviridae. Homology research and phylogenic analysis indicated that the dsRNA-L1 was a conspecific species of the previous reported Ustilaginoidea virens RNA virus 1, named Ustilaginoidea virens RNA virus Uv0901, and the dsRNA-L2 was a new number of the Victorivirus in the family Totiviridae, designed as Ustilaginoidea virens RNA virus 3.


Assuntos
Genoma Viral , Hypocreales/virologia , Oryza/microbiologia , Doenças das Plantas/microbiologia , Totiviridae/genética , Totiviridae/isolamento & purificação , Sequência de Bases , Hypocreales/fisiologia , Dados de Sequência Molecular , Filogenia , Totiviridae/classificação
20.
Virus Genes ; 48(2): 329-33, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24510355

RESUMO

In this study, three dsRNA segments from the rice false smut fungus Ustilaginoidea virens, the causal agent of a serious disease in rice, with molecular size ranging from 1.3 to 5 Kb, were isolated and named as dsRNA-L, dsRNA-M, and dsRNA-S. The complete nucleotide sequences of dsRNA-M and dsRNA-S were determined and analyzed. The dsRNA-M putatively encodes an RNA-dependent RNA polymerase, which is similar to that of the partitiviruses in the family Partitiviridae. Although the protein encoded by dsRNA-S showed less similarity to the typical coat protein of the virus in the family Partitiviridae, the structural analysis results indicated that the dsRNA-S might function as the capsid protein. We propose that the virus is Ustilaginoidea virens partitivirus 2-Uv0901, a new member, but distantly related to the newly proposed genus Gammapartitivirus with a distinct sequence pattern of capsid protein.


Assuntos
Genoma Fúngico , Oryza/microbiologia , Ustilaginales/genética , Sequência de Aminoácidos , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Ustilaginales/virologia
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