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1.
Appl Opt ; 61(31): 9247-9255, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36607060

RESUMEN

The brains of some insects can encode and decode polarization information and obtain heading angle information. Referring to the encoding ability of insects, exponential function encoding is designed to improve the stability of the polarized light compass artificial neural network. However, in the decoding process, only neurons with the largest activation degree are used for decoding (maximum value decoding), so the heading information contained in other neurons is not used. Therefore, average value decoding (AVD) and weighted AVD are proposed to use the heading information contained in multiple neurons to determine the heading. In addition, concerning the phenomenon of threshold activation of insect neurons, threshold value decoding (TVD) and weighted TVD are proposed, which can effectively eliminate the interference of neurons with low activation. Moreover, this paper proposes to improve the heading determination accuracy of the artificial neural network through pre-training. The simulation and experimental results show that the new, to the best of our knowledge, decoding methods and pre-training can effectively improve the heading determination accuracy of the artificial neural network.


Asunto(s)
Encéfalo , Redes Neurales de la Computación , Encéfalo/fisiología , Simulación por Computador
2.
BMC Cardiovasc Disord ; 19(1): 300, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-31847809

RESUMEN

BACKGROUND: Most coronary spastic angina patients are responsive to coronary vasodilators therapy, and stent implantation is not recommended for regular use. We reported the angiographic and intravascular ultrasound (IVUS) images of a rare case who responded poorly to medical treatment due to progressive atherosclerotic plaque at the spastic site. CASE PRESENTATION: A 60-year-old man complaining of 1-month history of episodic chest pain at rest was admitted to our hospital. The diagnosis of coronary spastic angina was made based on the angiographic evidence of vasospasm at the right coronary artery (RCA). The patient responded poorly to conventional medical treatment during the 1-year follow-up. The repeated angiography revealed totally occlusion of the proximal segment of the RCA at the same location as 1 year before, and IVUS demonstrated there was vulnerable plaque and thrombus at the site of spasm. Episodic chest pain ceased completely in the follow up period after stenting. CONCLUSION: Coronary spasm might present at the vessel site with advanced atherosclerotic plaque. For patients with refractory vasospastic angina and significant occlusion, stenting might be a viable and valuable treatment strategy under the guidance of intracoronary imaging.


Asunto(s)
Angina de Pecho/diagnóstico por imagen , Angina de Pecho/terapia , Enfermedad de la Arteria Coronaria/terapia , Vasoespasmo Coronario/terapia , Vasos Coronarios/diagnóstico por imagen , Intervención Coronaria Percutánea/instrumentación , Placa Aterosclerótica , Stents , Ultrasonografía Intervencional , Angina de Pecho/fisiopatología , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/fisiopatología , Vasoespasmo Coronario/diagnóstico por imagen , Vasoespasmo Coronario/fisiopatología , Vasos Coronarios/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Resultado del Tratamiento , Vasoconstricción
3.
Med Sci Monit ; 23: 948-952, 2017 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-28222067

RESUMEN

BACKGROUND Surgical treatment of acetabular fractures is one of the greatest challenges for orthopedic surgeons. Fixation of most displaced fractures requires extensive exposure, which may lead to complications, including blood loss, neural or vascular injury, postoperative infection, wound healing problems, and heterotopic bone formation. MATERIAL AND METHODS This study was conducted to certify an anatomic plate with an anterior column lag screw guiding device to repair the posterior acetabulum. Complete pelvic spiral computed tomography (CT) scan data were collected from 56 patients. The posterior column of the acetabulum was simulated with a lag screw. The guiding device for the plate was designed by measuring the position of the screw point and the direction and maximum diameter of the screw. RESULTS The distance from the screw point to the apex of the greater sciatic notch was farther in women than in men. The distance from the screw point to the ischial spine was also farther in women than in men. The q angle (front inclination angle) of the screw was lower in women than in men. The j angle (camber screw angle) was greater in women than in men. The success rate when using the guided device was significantly higher than when using traditional pedicle screws. CONCLUSIONS The guided device was very useful for improving placement success and accuracy rates of the acetabular posterior anatomical anterior column plate using antegrade lag screws, and for reducing surgical risk and injury.


Asunto(s)
Acetábulo/cirugía , Placas Óseas , Fijación Interna de Fracturas/métodos , Fracturas Óseas/cirugía , Adulto , Tornillos Óseos , Femenino , Humanos , Masculino
4.
Med Sci Monit ; 22: 3106-12, 2016 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-27584820

RESUMEN

BACKGROUND The aim of this study was to provide valid data for a plate-screw fixation model for fractured posterior-anterior columns of the acetabulum. MATERIAL AND METHODS Nineteen cadaveric bony hemi-pelvis specimens were obtained and 50 healthy adults were enrolled. The modified Stoppa approach and computed tomography (CT) imaging were used to collect the measured parameter data of the module. RESULTS The measured parameter data were as follows: OP, 0.96±0.32 cm in females and 0.92±0.16 cm in males (P>0.05); PI, 0.98±0.28 cm in females, and 0.75±0.23 cm in males (P>0.05); ÐÏ´, 59.68°±6.28° in females and 56.75°±3.22° in males (P>0.05); and Ðφ, 41.27°±2.76° in females and 34.31°±2.78° in males (P<0.05). The corresponding CT image data were as follows: PI, 1.08±0.22 cm in females and 0.85±0.27 cm in males (P>0.05); OP, 1.06±0.29 cm in females and 1.12±0.24 cm in males (P>0.05); ÐÏ´, 55.33°±4.00° in females and 55. 50°±3.43° in males (P>0.05); and Ðφ was 39.21°±2.45°in females and 35.58°±2.31°in males (P<0.05). No significant difference with respect to sex and side existed between specimens and healthy adults (P>0.05). CONCLUSIONS The measured parameter data obtained in healthy adults and cadaveric specimens provided an anatomic basis for the designation of the guide module, and thus confirmed the accuracy and safety of screw placement in fractured columns of the acetabulum.


Asunto(s)
Acetábulo/cirugía , Fijación Interna de Fracturas/métodos , Fracturas Óseas/cirugía , Cirugía Asistida por Computador/métodos , Acetábulo/diagnóstico por imagen , Acetábulo/lesiones , Adulto , Anciano , Placas Óseas , Tornillos Óseos , Cadáver , Femenino , Fijación Interna de Fracturas/instrumentación , Fracturas Óseas/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Cirugía Asistida por Computador/instrumentación , Tomografía Computarizada por Rayos X/métodos
5.
Heliyon ; 10(1): e21700, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38226259

RESUMEN

With the Goal-Establishment of "carbon compliance" and "carbon neutrality", enterprises should upgrade "green development" to a strategic position and implement it through all aspects of business operations. Green supplier selection is the initial phase of supply chain management, therefore a green supplier evaluation system is needed to achieve green development. Based on a literature analysis, We selected 45 metrics as candidates for evaluating suppliers. Then through expert interviews, some indicators were revised and supplemented, and finally a green supplier evaluation index system for high energy-consuming enterprises was constructed. A unique aspect of this paper is the introduction of rough number theory into the supplier evaluation process to improve the indicator assignment and the grey correlation TOPSIS method, which optimizes the processing of uncertain semantic information in the evaluation process. The rough number-grey correlation TOPSIS supplier evaluation model developed in this paper has been verified to be applicable and stable in case studies and successfully implemented.

6.
Environ Sci Pollut Res Int ; 30(12): 33849-33861, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36502477

RESUMEN

To direct financial resources for achieving the goal of sustainable development, Chinese government has devoted increasing efforts to developing green finance. However, few studies explored the relationship between green finance and environmental governance. Thus, this paper first theoretically discusses the interactive connection between green finance and environmental governance. And then we construct two comprehensive indicator systems and use entropy method to calculate green finance index (GFI) and environmental governance index (EGI) for 30 provinces of China from 2004 to 2020. The theoretical analysis unveils the complementary and mutual reinforcing relationship of the interaction between green finance and environmental governance through green industry. Using the data of GFI and EGI, the coupling coordination degree of green finance and environmental governance (CCDGE) is measured by coupling coordination model. The trend analysis discovers that GFI is increasing over time while EGI starts decreasing from 2013. Although GFI has grown more rapidly than EGI, but the development of green finance still lags behind environmental governance because of its short history. Just because of the uncoordinated development between green finance and environmental governance, CCDGE has been hovering in the moderate coupling coordination stage for a long time and still has a great distance to the high coupling coordination level. These findings imply that the relationship between green finance and environmental governance is still in a state of disorderly development that restricts each other. Furthermore, the findings of spatial-temporal analysis show there are obvious regional differences in GFI and EGI and the interactive effect between green finance and environmental governance. Specifically, GFI and EGI in eastern China are the highest, while CCDGE presents with a ladder decline status of "eastern region > central region > northeast region > west region." Our findings provide vital references for policymakers to promote the coupling coordination development between green finance and environmental governance.


Asunto(s)
Conservación de los Recursos Naturales , Política Ambiental , China , Desarrollo Económico , Análisis Espacio-Temporal
7.
J Mater Sci Mater Med ; 23(3): 697-710, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22311074

RESUMEN

A hydrogel which will undergo macroscopic transition responding to redox stimuli is prepared. Mercapto precursors are prepared from 4-armed polyethylene glycol and after deprotection of thiolate anions, they can transform into disulfide crosslinked hydrogels within 3 min by responding to oxidant H(2)O(2). Desirable elasticity is exhibited with a wide range of storage modulus from 50 Pa to 14 kPa through rheological investigation. In addition, the hydrogels are found to be hydrolytically stable but degrade within 75 days when exposed to reductant such as glutathione (GSH). So gelation time and degradation behavior can be regulated by concentrations of precursor, oxidant, reductant, temperature, and pH value. Notably, interest arises from the long-period degradation under low GSH concentration of 0.01 mM that is similar to extracellular level, but not the fast disintegration under high concentration intracellular, providing the possibility of "smart" degradation responding to those cell-secreted biomacromolecules during the process of tissue regeneration. Furthermore, both hydrogels and their degradation products show cell viability above 90% culturing with C2C12 cells, representing nontoxic properties. Such a stimuli-responsive degradation strategy will give promising application in tissue repair and regeneration; especially enable the achievement of matching the degradation kinetics with physiological environment.


Asunto(s)
Hidrogeles , Polietilenglicoles/química , Animales , Línea Celular , Espectroscopía de Resonancia Magnética , Ratones , Oxidación-Reducción , Reología
8.
Front Psychol ; 13: 842277, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35465524

RESUMEN

Till now, comprehensive and quantitatively meaningful analyses of stock market participation outcomes of retail investors have been limited by data sources in developing countries. This article devised a special questionnaire related to stock investment to measure the financial literacy (FL) and stock investment return (SIR) for the subjects with stockownership in China and to theoretically and empirically study the effects of objective FL, self-assessed FL, and their composite FL on SIR. The results of the comparative analysis showed that self-assessed FL has a greater effect on SIR than objective FL, and the effect is mediated by risk preference. In addition, we found that competent and overconfident respondents have higher SIR, while under confident respondents cannot gain from the stock market. We also found that risk preference has a positive mediating effect in the relationship between competence and overconfidence and SIR, and a negative mediating effect in the relationship between under confidence and SIR. We thus concluded that confident investors can gain more stockholding returns via taking more risks regardless of the level of their actual financial knowledge. Our findings would be a meaningful complement to the studies of stock market participation.

9.
Front Oncol ; 12: 1019153, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36419894

RESUMEN

Copper is an essential trace element in an organism, and changes in copper levels in vivo often indicate a diseased state. Copper and immunity have been discussed since the last century, with copper deficiency significantly affecting the development and function of the immune system, such as increased host susceptibility to various pathogens, decreased number and impaired function of neutrophils, reduced antibacterial activity of macrophages, decreased proliferation of splenocytes, impaired B cell ability to produce antibodies and impaired function of cytotoxic T lymphocyte and helper T cells. In the past 20 years, some studies have shown that copper ions are related to the development of many tumors, including lung cancer, acute lymphoid leukaemia, multiple myeloma and other tumors, wherein copper ion levels were significantly elevated, and current studies reveal that copper ions are involved in the development, growth and metastasis of tumors through various pathways. Moreover, recent studies have shown that copper ions can regulate the expression of PD-L1, thus, attention should be paid to the important role of copper in tumor immunity. By exploring and studying copper ions and tumor immunity, new insights into tumor immunity could be generated and novel therapeutic approaches to improve the clinical prognosis of patients can be provided.

10.
Front Psychol ; 12: 715003, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34630224

RESUMEN

Conflicts in land exploration are incisive social problems which have been the subject in many studies. Risk assessment of land conflicts is effective to resolve such problems. Specifically, fuzzy mathematics and the analytic hierarchy process were combined together to evaluate risk in land conflicts in our work, which is proved useful to solve uncertainty and imprecision problems. Based on the analysis of the principles for the risk assessment of a land conflicts index system, a set of risk assessment indexes using the fuzzy analytic hierarchy process (FAHP) was presented. The results show that the overall risk is at medium level, and the risk of the feasibility index and controllability index need to be paid more attention to. The contribution of this article is reflected in two aspects: (1) the application of FAHP in risk assessments of land conflicts is effective and valid; (2) it is helpful for governments to establish a stricter management system of work safety for conflicts in land exploration based on the risk assessment results.

11.
J Med Chem ; 64(16): 12379-12396, 2021 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-34374537

RESUMEN

Enhancing neuronal α7 nicotinic acetylcholine receptor (α7 nAChR) function can alleviate cognitive deficits. Here, we report the design, synthesis, and evaluation of N-(4-(trifluoromethoxy)phenyl)-1,3,5-triazin-2-amine derivatives 8-10 as a series of novel α7 nAChR positive allosteric modulators (PAMs). The representative compound 10e functions as a type I PAM with an EC50 of 3.0 µM and approximately 38-fold enhancement of α7 current in the presence of agonist acetylcholine (100 µM). It specifically enhances α7 current with high selectivity. Compound 10e shows good pharmacokinetic property in mice. Intraperitoneal injection of 10e (3 mg/kg) exhibits sufficient blood-brain barrier penetration in mice. Furthermore, 10e can also rescue the auditory gating deficit in mice with schizophrenia-like behavior. Molecular docking of 10e with homopentameric α7 nAChR reveals a new mode of action. These results support the potential of 10e for treatment for schizophrenia and Alzheimer's disease.


Asunto(s)
Agonistas Nicotínicos/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Triazinas/uso terapéutico , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Animales , Maleato de Dizocilpina , Femenino , Humanos , Masculino , Ratones Endogámicos C57BL , Simulación del Acoplamiento Molecular , Agonistas Nicotínicos/síntesis química , Agonistas Nicotínicos/metabolismo , Agonistas Nicotínicos/farmacocinética , Esquizofrenia/inducido químicamente , Filtrado Sensorial/efectos de los fármacos , Triazinas/síntesis química , Triazinas/metabolismo , Triazinas/farmacocinética , Xenopus laevis , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
13.
Avian Dis ; 51(1): 96-105, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17461273

RESUMEN

In this paper, we report on the evaluation of five influenza antigen detection tests by avian influenza H5N 1 virus-positive swab samples to estimate their diagnostic sensitivity. The tests included two chromatographic immunoassays, an H5 avian influenza-specific antigen detection enzyme-linked immunosorbent assay (ELISA), an influenza A antigen detection ELISA, and an H5 rapid immunoblot assay. The results showed that the overall sensitivities of these tests ranged from 36.3% to 51.4% (95% confidence interval ranging from 31.0% to 57.0%), which were comparable to Directigen Flu A antigen detection tests but substantially lower than genome detection methods. Diagnostic sensitivity performance is a function of the concentration of antigens in samples and the analytical sensitivity of the individual test. The test sensitivities were significantly higher for sick and dead birds by cloacal, tracheal, or tissue swabs than for fecal swabs from apparently healthy birds, and these tests would not be suitable for surveillance testing of clinically healthy birds. Furthermore, the sensitivity for testing tracheal and cloacal swabs from waterfowl and wild birds was not as good as for chickens. This was most likely to be associated with variation in virus titers between specimens from different bird species. However, the tests showed good sensitivities for testing brain swabs from clinically affected waterfowl species. The results indicate that these antigen detection tests could be used for preliminary investigations of H5N 1 outbreaks as a low-cost, simple flock test in sick and dead birds for the rapid detection of H5N1 infection. However, the relatively low sensitivity of the tests as individual bird tests means that they should be used on optimal clinical specimens from diseased birds, testing birds on a flock basis, or testing samples as close to the onset of disease as possible before viral titers diminish. They should be followed up by confirmatory tests, such as reverse transcription polymerase chain reaction or viral culture, wherever possible but could assist in facilitating rapid investigations and control interventions.


Asunto(s)
Antígenos Virales/análisis , Aves/virología , Inmunoensayo/veterinaria , Subtipo H5N1 del Virus de la Influenza A/inmunología , Subtipo H5N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/diagnóstico , Gripe Aviar/inmunología , Animales , Antígenos Virales/inmunología , Genotipo , Inmunoensayo/métodos , Subtipo H5N1 del Virus de la Influenza A/genética , Sensibilidad y Especificidad
14.
Zhonghua Nan Ke Xue ; 13(9): 777-9, 2007 Sep.
Artículo en Zh | MEDLINE | ID: mdl-17929550

RESUMEN

OBJECTIVE: To investigate the effects of testosterone on extracellular signal-regulated kinase l/2 ( ERK1/2) phosphorylation in human umbilical vein endothelial cells (HUVEC). METHODS: Activations of ERK1/2 stimulated by physiological testosterone were detected by Western blotting in cultured HUVEC. RESULTS: A rapid phosphorylation expression of ERK1/2 was observed by treatment of the HUVECs with 3 x 10(-8) mol/L testosterone, especially at 30 minutes. This phosphorylation was greatly inhibited by incubation with androgen receptor antagonist flutamide for 3 hours previously. CONCLUSION: Testosterone at physiological concentrations induces the mitogen-activated protein kinase (MAPK, ERK1/2 and MEK1/2) phosphorylation within a short time, and flutamide could impair the process.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Testosterona/farmacología , Antagonistas de Receptores Androgénicos , Western Blotting , Células Cultivadas , Células Endoteliales/citología , Células Endoteliales/metabolismo , Activación Enzimática/efectos de los fármacos , Humanos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Fosforilación/efectos de los fármacos , Receptores Androgénicos/metabolismo , Venas Umbilicales/citología
15.
J Am Heart Assoc ; 6(7)2017 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-28684641

RESUMEN

BACKGROUND: Several studies have suggested that cytomegalovirus infection is likely associated with an increased relative risk of cardiovascular disease (CVD); however, the results are inconsistent. We aimed to provide a systematic review and meta-analysis of community-based prospective studies assessing the association between cytomegalovirus infection and relative risk of CVD. METHODS AND RESULTS: We searched Medline and EMBASE to retrieve prospective studies that reported risk estimates of the association between cytomegalovirus infection and relative risk of CVD. The search yielded 10 articles including a total of 34 564 participants and 4789 CVD patients. Overall, exposure to cytomegalovirus infection was associated with a 22% (relative risk: 1.22, 95% CI: 1.07-1.38, P=0.002) increased relative risk of future CVD. We estimated that 13.4% of CVD incidence could be attributable to cytomegalovirus infection. CONCLUSIONS: In conclusion, cytomegalovirus infection is associated with a significantly increased relative risk of CVD.


Asunto(s)
Infecciones por Citomegalovirus/epidemiología , Isquemia Miocárdica/epidemiología , Accidente Cerebrovascular/epidemiología , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/mortalidad , Infecciones por Citomegalovirus/virología , Femenino , Humanos , Incidencia , Masculino , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/mortalidad , Isquemia Miocárdica/virología , Oportunidad Relativa , Pronóstico , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/virología , Factores de Tiempo
16.
Zhonghua Gan Zang Bing Za Zhi ; 12(1): 11-2, 2004 Jan.
Artículo en Zh | MEDLINE | ID: mdl-14761272

RESUMEN

OBJECTIVE: To understand the prevalence of sub-clinical infection of hepatitis E virus (HEV) among blood donors. METHODS: A cluster sampling strategy was used to sample all blood donors from July to August in 2002 in Beijing. Their blood was tested for IgM and IgG antibody against HEV. RESULTS: The prevalence of anti-HEV IgM among blood donors in Beijing was 1.74%. The rate of abnormal alanine aminotransferase (ALT) in anti-HEV IgM positive donors is significantly higher than anti-HEV IgM negative donors. Among all ALT abnormal donors, 2.68% can be associated with HEV sub-clinical infection. The percentage is similar with HBV but higher than HCV. CONCLUSION: There are sub-clinical infection of HEV among blood donors, which is one of the cause of abnormal ALT in the donors.


Asunto(s)
Donantes de Sangre , Anticuerpos Antihepatitis/sangre , Virus de la Hepatitis E/inmunología , Hepatitis E/epidemiología , Inmunoglobulina M/sangre , Adulto , Alanina Transaminasa/sangre , Femenino , Hepacivirus/inmunología , Humanos , Masculino
17.
Chinese Journal of Dermatology ; (12): 652-655, 2019.
Artículo en Zh | WPRIM | ID: wpr-797851

RESUMEN

Chronic spontaneous urticaria (CSU) is characterized by recurrent wheals with severe itching, and greatly affects the life quality of patients. The European guideline on chronic urticaria recommends the anti-IgE monoclonal antibody omalizumab as the only third-line therapy for patients with CSU whose condition can not be controlled by high doses of antihistamines. Although a lot of researches have shown that omalizumab is effective and safe for the treatment of CSU, its therapeutic mechanisms have not yet been fully elucidated. This review summarizes therapeutic mechanisms of omalizumab in the treatment of CSU, and indices for predicting and monitoring its clinical efficacy.

18.
Chinese Journal of Dermatology ; (12): 652-655, 2019.
Artículo en Zh | WPRIM | ID: wpr-755824

RESUMEN

Chronic spontaneous urticaria (CSU) is characterized by recurrent wheals with severe itching,and greatly affects the life quality of patients.The European guideline on chronic urticaria recommends the anti-IgE monoclonal antibody omalizumab as the only third-line therapy for patients with CSU whose condition can not be controlled by high doses of antihistamines.Although a lot of researches have shown that omalizumab is effective and safe for the treatment of CSU,its therapeutic mechanisms have not yet been fully elucidated.This review summarizes therapeutic mechanisms of omalizumab in the treatment of CSU,and indices for predicting and monitoring its clinical efficacy.

19.
PLoS One ; 8(5): e64323, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23750192

RESUMEN

Several approaches have been proposed for near real-time detection and prediction of the spread of influenza. These include search query data for influenza-related terms, which has been explored as a tool for augmenting traditional surveillance methods. In this paper, we present a method that uses Internet search query data from Baidu to model and monitor influenza activity in China. The objectives of the study are to present a comprehensive technique for: (i) keyword selection, (ii) keyword filtering, (iii) index composition and (iv) modeling and detection of influenza activity in China. Sequential time-series for the selected composite keyword index is significantly correlated with Chinese influenza case data. In addition, one-month ahead prediction of influenza cases for the first eight months of 2012 has a mean absolute percent error less than 11%. To our knowledge, this is the first study on the use of search query data from Baidu in conjunction with this approach for estimation of influenza activity in China.


Asunto(s)
Gripe Humana/epidemiología , Vigilancia de la Población , Medios de Comunicación Sociales , Humanos , Modelos Estadísticos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Artículo en Zh | WPRIM | ID: wpr-231017

RESUMEN

To establish a method for determining the contents of six alkaloids (jatrorrhizine hydrochloride, columbamine hydrochloride, epiberberine hydrochloride, coptisine hydrochloride, palmatine hydrochloride, berberine hydrochloride) in six types of Coptidis Rhizoma pieces (crude pieces, ginger juice stir-fried pieces, vinegar stir-fried pieces, wine steamed pieces, wine stir-fried pieces, evodiae juice stir-fried pieces) by RP-HPLC, and explore the relationship with the curative effect of traditional Chinese medicine (TCM) and pharmacodynamics results. The chromatographic column was Welch XtimateTM C₁₈ (4.6 mm×250 mm, 5 μm), with 0.1% triethylamine solution (adjust pH at 10 with ammonium bicarbonate and ammonia) as mobile phase A and acetonitrile as mobile phase B for gradient elution (0-15 min, 10%-25%B; 15-25 min, 25%-30%B; 25-40 min, 30%-45%B) at a rate of 1.0 mL•min⁻¹. The column temperature was set at 30 ℃, and the wavelength was set at 270 nm. The six alkaloids showed a good linear relationship within the range of 0.85-16.96 mg•L⁻¹ (r=0.999 7), 1.25-24.96 mg•L⁻¹ (r=0.999 9), 2.05-40.96 mg•L⁻¹ (r=0.999 9), 3.65-72.96 mg•L⁻¹ (r=0.999 9), 2.88-57.60 mg•L⁻¹ (r=0.999 8), and 13.25-264.96 mg•L⁻¹ (r=0.999 6) respectively. The average recoveries (n=9) of the six alkaloids were 102.4% (RSD 1.2%), 101.8% (RSD 1.3%), 100.3% (RSD 1.8%), 100.7%(RSD 1.8%), 101.2% (RSD 1.5%) and 97.90% (RSD 2.0%) respectively, and their average contents were 3.55, 4.49, 9.12, 19.17, 15.69, 62.56 mg•g⁻¹, respectively. This determination method was accurate and repeatable, which could be used for the content determination in six types of Coptidis Rhizoma pieces. Data analysis on contents determination and preliminary pharmacodynamics results was conducted by using principal component analysis (PCA) and hierarchical clustering analysis (HCA). The analysis results showed that three types of Coptidis Rhizoma pieces (wine steamed pieces, wine stir-fried pieces, and evodiae juice stir-fried pieces) had significant differences with crude pieces, and the wine steamed Coptidis Rhizoma pieces showed most difference with crude pieces especially, mainly related to triglyceride (TG) and fasting blood glucose levels (FBG) in serum. In addition, columbamine hydrochloride was most affected among the six alkaloids. Those three types of Coptidis Rhizoma pieces (wine steamed pieces, wine stir-fried pieces, and evodiae juice stir-fried pieces), had more advantages for "anti-diabetes" in TCM clinical application, especially in the treatment of diabetic hyperlipidemia.

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