Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros











Tipo de estudio
Intervalo de año de publicación
1.
Int J Biol Macromol ; 271(Pt 1): 132195, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38816294

RESUMEN

XPS, GPC, FT-IR, and GC-MS analyses were conducted on corn straw tar and 70# petroleum asphalt. The results indicate that the sulfur content in corn straw tar is lower than that in petroleum asphalt, potentially mitigating the volatilization of harmful substances upon substituting petroleum asphalt. This finding serves as evidence for the substantial presence of phenolic substances in corn straw tar. Upon employing the BOX-Behnken response surface analysis and utilizing resin yield as the evaluation index, the significance of three factors was established as follows: reaction time > phenol molar ratio > straw tar content. Based on the secondary multiple regression model, the optimal conditions for synthetic resin production are a phenolic mole ratio of 0.8, a reaction time of 125 min, and a straw tar dosage of 10 %. An assessment of resin viscosity at different VI temperatures reveals that corn stover tar can partially replace phenol and formaldehyde in the condensation reaction. Additionally, viscosity improvement is observed at elevated temperatures. Thermal gravimetric(TG) spectroscopy indicates lower mass loss in B-PF resin at high temperatures compared to PF resin or corn stover tar. In the evaluation of biological bitumen performance, it is discerned that the mixing amount of the prepared biological bitumen should be controlled at approximately 10 % of its performance. This ensures optimal efficacy without adversely affecting the performance of petroleum bitumen.


Asunto(s)
Hidrocarburos , Fenoles , Zea mays , Zea mays/química , Hidrocarburos/química , Fenoles/química , Fenoles/análisis , Viscosidad , Resinas Sintéticas/química
2.
Lett Appl Microbiol ; 76(10)2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37833237

RESUMEN

The occurrence of Giardia and Cryptosporidium (oo)cysts in drinking source water poses a serious public health risk. Here, we established a method that combines membrane concentration and real-time polymerase chain reaction (PCR) to quantify Giardia and Cryptosporidium in drinking water. The water samples were filtered through a cellulose membrane to collect Giardia and Cryptosporidium, and then nucleic acids were extracted. Specific primers and probes were designed and synthesized according to the gph gene sequence of Giardia and 18S rRNA gene sequence of Cryptosporidium. The concentrations of the two targets were determined using real-time PCR technology. The sensitivity, specificity, and stability of the method were evaluated. Our findings revealed that the detection limits of real-time PCR method for detecting Giardia and Cryptosporidium were 0.926 and 0.65 copy/µL, respectively; the spiked recovery rates were above 60% and 38%, respectively, and relative standard deviations were under 0.95% and 2.26%, respectively. Therefore, this effective procedure based on the membrane concentration method and real-time PCR will be useful for detecting Giardia and Cryptosporidium in drinking water for purpose of continuous environmental monitoring.


Asunto(s)
Criptosporidiosis , Cryptosporidium , Agua Potable , Humanos , Cryptosporidium/genética , Giardia/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
3.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-862512

RESUMEN

Objective To understand the epidemiological characteristics and variation of H3N2 influenza virus hemagglutinin (HA) gene in Changzhou from 2017 to 2018. Methods Throat swab specimens of the influenza-like cases were collected from Changzhou Influenza Monitoring Sentinel Hospital from April 2017 to March 2018. RNA was extracted from the specimens for influenza diagnosing and genotyping using real-time RT-PCR.H3N2 positive samples were isolated, and extracted RNA was used for amplification, sequencing and phylogenetic analysis of HA gene. Results From April 2017 to March 2018, 28 strains of influenza A (H3N2) virus were isolated. After gene sequencing, a phylogenetic tree was constructed. It was found that all of the strains belonged to Group3C.2a, which was similar to the vaccine strain A/Hong Kong/4801/2014. The HA amino acid sequence difference was analyzed and compared between the H3N2 influenza virus strains isolated in Changzhou and the vaccine strain A/Hong Kong/4801/2014. It was found that the epidemic strain isolated in Changzhou was in the HA epitope (A-E) region. Ten amino acid site mutations in the HA epitope (A-E) region and two amino acid site mutations in the stem region of HA antigen were found. Conclusion From April 2017 to March 2018, the influenza virus H3N2 prevalent in Changzhou was distributed on the same evolutionary branch with the vaccine strain A/Hong Kong/4801/2014 (group 3C.2a), rendering the popular trend of one subgroup. However, some amino acid sites of the HA epitope had variations, suggesting that mutations may occur, which may affect the immune effect of the vaccine. Monitoring needs to be strengthened in the future work.

4.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-807032

RESUMEN

Thirty eight patients with type 2 diabetes mellitus (T2DM) signed with the Lingering Garden Subdistrict Community Health Service Center of Suzhou Gusu District from October to December 2015 were enrolled in the study. The patients were classified as low risk group (n=3), moderate risk group (n=11), high risk group (n=21) and extremely high risk group (n=3) according to risk stratification of the JADE program based on estimated glomerular filtration rate (eGFR) and risk factors [obesity, dyslipidemia, hypertension, diabetic retinopathy, urinary protein creatinine ratio, foot disease, glycosylated hemoglobin A1c(HbA1c), fasting plasma glucose(FPG) or non fasting plasma glucose]. The patients were managed by a team consisting of general practitioners, general nurses and specialists; the individualized management was implemented with reduction of controllable risk factors and complications as the goal. After one year of management (March 2016 to February 2017) the indicators of T2DM were evaluated. The results showed that the TC, LDL-C, FPG and HbA1c levels were significantly improved in both moderate and high risk groups (P<0.05); the TC, LDL-C and FPG levels in the extremely high risk group were also significantly improved (P<0.05).

5.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-513451

RESUMEN

BACKGROUND:Numerous diseases like cardiac hypertrophy and intervertebral disc degeneration are known to be implicated in the changes of mechanical stress acting on surrounding tissues or cells, and autophagy contributes to the pathogenesis of these diseases. OBJECTIVE:To review the effects of mechanical factors on autophagy in different tissues and the underlying molecular mechanisms, thereby providing references for the research of autophagy and the prevention and treatment of related diseases. METHODS:A search of Web of Science and PubMed databases was performed for the literatures addressing the effects of mechanical factors on autophagy using the English keywords ofautophagy, mechanicaland the articles were summarized systematically. Finally, 52 literatures were enrolled according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION:Mechanical factors make great effects on autophagy of various cells, such as myocardial cells, endothelial cells, chondrocytes and skeletal muscle cells. Autophagy is a self-protective reaction, and the mechanical stress of physiological conditions induces autophagy to maintain cellhomeostasis, normal function and survival. The mechanism of autophagy induced by mechanical stress may involve PI3K-AKT-mTOR, oxygen free radical, AKT-FoxO and other pathways, and the definite mechanism needs to be further studied.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA