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1.
Heliyon ; 10(6): e27168, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38509964

RESUMO

Various studies have demonstrated that employing ESR spin trapping to detect free radicals yields valuable insights into the vulnerability of bulk oils to oxidation. Consequently, this method can be employed to assess and compare the oxidative stability of different samples. This study was conducted to investigate the production and transformation of free radicals and trans isomers in linseed oil when subjected to different temperatures and durations of heating. These analyses revealed that the peak levels of free radicals PBN adducts were evident in linseed oil heated to 120 °C, while these levels decreased within 90 min and were absent at a higher temperature of 180 °C. Free radical PBN adducts were readily degraded at 180 °C. Levels of heat-induced trans isomers rose in linseed oil samples with rising temperatures but began to degrade at temperatures exceeding 240 °C partially. The content examination of these trans isomers revealed that the double bonds located at positions 9 and 15 exhibited a higher susceptibility to isomerization compared to the double bond at position 12. Furthermore, the values of k and Ea indicated that the synthesis of tri-trans-α-linolenic acid (TALAs) was more challenging compared to double-TALAs, and double-TALAs were more challenging than single-TALAs. This was because the tri-TALAs has a higher Ea value than the mono-TALAs and double-TALAs. The study has demonstrated that subjecting linseed oil to high-temperature heating leads to the production of free radicals and trans isomers. And PBN radical adduct is unstable at 180 °C and the double bonds at positions 9 and 15 could be isomerized more easily than that at position 12. These results indicated that controlling the formation of free radicals and single-TALAs isomers may be the key way to reduce the trans isomers of linolenic acid during cooking oil heating. In the follow-up study, we found that VE, VK3, ethyl caffeic acid and resveratrol had significant inhibitory effects on the formation of TALAs of linolenic acid, and the highest inhibitory rate of resveratrol with 5% addition could be reached to 30.86%. The above substances can be applied to the thermal processing of linseed oil to prevent the formation of TALAs.

2.
Cities ; 126: 103712, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35505901

RESUMO

The COVID-19 pandemic has caused significant mobility restrictions and generated profound impacts on global socio-economic development. Mobility restrictions can generate significant impacts on the demand and supply sides of the rental housing market. By taking 77 large Chinese cities as cases, this research establishes a stepwise mediation effect test to evaluate the impacts of the pandemic on the rental housing market during Q1 2020. The results show that the confirmed cases were negatively associated with rental unit transactions, and the inter-city and intra-city movement played a significant role of mediating effects. Meanwhile, the impact of pandemic on rents lagged behind rental transaction in China's large cities, and the strict mobility controls caused the high vacancy rate of rental housing, leading to the bankruptcy of many housing rental agencies. Our research add to the burgeoning literature examining the mediating effect of mobility control between confirmed case and housing rental market. It demonstrates that the change of housing rental market induced by pandemic in China is the short-term influence on rental unit transaction, which is different from western countries. In China, a country with the most strict mobility control, the challenges come from the impact of pandemic on housing rental agencies.

3.
Food Sci Nutr ; 9(7): 3863-3872, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34262743

RESUMO

In the present study, we investigated the effects of thermal preservation, such as pasteurization, and nonthermal preservation, including irradiation, sodium dehydroacetate (SDHA), and nisin, on the quality of red sour soup after storage. Single-factor experiments were used to optimize the parameters of different processing technologies, and the best irradiation dose and heating temperature were 4 kGy and 85℃, respectively. The optimal additive amounts of SDHA and nisin were 150 mg/500 g. During the shelf storage experiment, prepared red sour soup was stored at room temperature in the glass bottles, and further analyses were carried out up to 5 weeks of storage. The quality of red sour soup was evaluated by microflora and sensory analysis. The results showed that Lactobacillus, Streptomyces, Pediococcus, Pichia, Kazachstania, and Candida were the main microorganisms in all samples, and there were no harmful microorganisms. The sensorial attributes were observed, including different parameters, such as odor, organic acid content, color, taste, texture, apparent viscosity, and thixotropy. All of the data showed that the irradiated groups were more dramatically changed compared with the other groups, while these changes did not directly affect the sensory quality of the products. Consequently, irradiation could be used as an ideal quality preservation method for the red sour soup to reduce the impact of heat treatment and chemical additives on the quality of characteristic food.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-863932

RESUMO

Objective:To investigate the relationship between plasma fibrinogen (FBG) level and p53 protein expression of tumor tissue in breast cancer, and to study the relationship between the parameters of plasma FBG level and p53 protein expression in tumor tissue and the prognosis of breast cancer.Methods:A total of 177 breast cancer patients who underwent surgery in the Second Affiliated Hospital of Hainan Medical University between Jan. 2012 and Oct. 2016 were included in the study. The data, including the general clinicopathological characteristics, the expression of p53 protein with immumohistochemical (IHC) staining, and plasma FBG level within 1 week before surgery, were collected. Chi-square test was used to analyze the relationship between the different levels of plasma FBG and the parameters of general clinicopathological characteristics and p53 protein, and binary Logistic regression was used for multivariate analysis. Kaplan-meier survival analysis and COX regression analysis were used for univariate analysis and multivariate analysis of IDFS, respectively.Results:Univariate analysis showed that plasma FBG>2.75 g/L had significant positive correlation with age>50 and positive p53 expression in tumor tissue ( P values were <0.001 and 0.006, respectively) . Multivariate analysis showed that positive p53 expression in tumor tissue ( OR 2.256, 95% CI 1.192 to 4.271, P<0.001) and age>50 years ( OR 3.712, 95% CI 1.967 to 7.002, P<0.001) were independent correlation factors for plasma FBG>2.75 g/L. Kaplan-Meier survival analysis results showed that the aged>50 years, T>2 cm, lymph node metastasis, Ⅲ stage, plasma FBG>2.75 g/L, positive p53 expression in tumor tissue were adverse prognostic factors of IDFS. COX regression analysis results showed that plasma FBG>2.75 g/L ( HR 6.226, 95% CI 3.863 to 10.033, P<0.001) , positive p53 expression in tumor tissue ( HR 1.864, 95% CI 1.133 to 3.066, P=0.014) and Ⅲ stage ( HR 10.382, 95% CI 5.942 to 18.141, P<0.001) were adverse prognostic factors of IDFS, and adjuvant endocrine therapy ( HR 0.427, 95% CI 0.275 to 0.663, P<0.001) was a favourable prognostic factor for IDFS. Conclusions:The expression of p53 protein was significantly correlated with high plasma FBG level in breast cancer. Both p53 protein expression and high plasma FBG level are associated with poor prognosis of breast cancer. On the basis of traditional pathological prognostic indicators, the detection of plasma FBG and p53 protein in tumor tissue may contribute to increase the prognostic information in breast cancer.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-619961

RESUMO

β-Cyclodextrin-N-vinyl-2-pyrrolidone (CDM-NVP) copolymer was prepared by free radical chain reaction of N-vinyl-2-pyrrolidone (NVP) and β-CD maleate (CDM) with γ-ray as initiator.The synthesis conditions of CDM-NVP polymer were as follows: mass ratio of CDM to NVP was 1∶0.7 (CDM 3.6 g and NVP 2.52 g), irradiation dosage was 4 kGy, and DMF aqueous solution (50%, V/V) was set at 20 mL.Under the synthesis conditions, the yield of CDM-NVP was 84% and the weight-average molecular weight was 20 kD.The natamycin (NM) and carbendazim (MBC) could form stable inclusion complexes with CDM-NVP copolymer, and the solubility and fungicidal activity of the complexes were investigated.The stability constant of NM·CDM-NVP and MBC·CDM-NVP complexes at 303 K were 12, 988.54 L/mol and 865.94 L/mol, respectively.The complexes were characterized using phase solubility diagrams, nuclear magnetic resonance (NMR) spectra and ultraviolet (UV) spectra.The analysis of the biological activities of these two complexes indicated that they possessed enhancing fungicidal activities compared to NM and MBC alone.

6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-486667

RESUMO

Objective To investigate the difference of two models of respiratory failure in preterm infants with nasal continuous positive airway pressure(nCPAP)and nasal biphasic positive airway pressure (nBiPAP).Methods Comparative analysis of 81cases of premature infants with respiratory failure requi-ring respiratory support was needed.They were applied nCPAP and nBiPAP ventilation mode treatment.The use of breathing machine and total oxygen inhalation time,the number of treatment failures,the PEEP param-eters of the ventilator,the total number of recent complications and secondary infections were compared.Re-sults In the nBiPAP treatment group,the average time of noninvasive ventilation was(96.34±31.5)h,the total time of oxygen inhalation was(10.11 ±9.39)d,3cases of treatment failure,the incidence of severe complications was 5.56%(2/36),PEEP (4.08±0.73)cmH2O (1cmH2O =0.098kPa ).In the nCPAP group,the average time of noninvasive ventilation was(114.14±41.69)h,the total time of oxygen inhalation was(17.53±15.96)d,15cases were failed,the incidence of severe complications was 15.56%(7/45), PEEP(5.11±1.01)cmH2O.There were significant differences between the two groups(P﹤0.05).But there were no significant differences in infection control and patent ductus arteriosus (P ﹥0.05).Conclusion nBiPAP as one of the first choice treatment for premature infants with respiratory failure significantly better than nCPAP,as soon as the proper use can avoid invasive ventilation.

7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-490113

RESUMO

Objective To analyze the voluntary blood donors of Shaoguan city in recent 10 years HIV infection status and distri‐bution characteristics ,and to take effective prevention and control measures ,in order to reduce the risk of HIV infection through blood transfusion .Methods HIV screening test in the early by the reagent of two different manufacturers ,from 2005 to 2014 vol‐untary blood donors specimens of 265 771 doses of blood donation in Shaoguan ,and early screening positive specimens confirmed by Center for Disease Control of Shaoguan .Results The voluntary blood donors of Shaoguan in the 10 years that initial screening test anti‐HIV positive were 310 cases ,and 35 cases confirmed positive;The confirmed positive rate was 1 .317/10 000;The HIV infec‐tion rate in 2012 was highest (2 .867/10 000) and there were 9 cases ,which was significant difference (P<0 .05) .The district of the maximum rate was New Fengxian ,which was 5 .369/10 000 ,and different districts had significant difference (P<0 .05) .The epidemiology survey about HIV infections found that male were 30 cases(85 .71% ) ,which was significantly more than women;By age distribution ,most HIV infections were 18 to 35 years old young adults ,which accounted 26 cases(74 .29% ) .Married and un‐married people infected respectively accounted 28 .57% and 71 .43% .The occupations of HIV infections were scattered with farm‐ers ,staffers ,the service industry ,cadres in the majority .The HIV infection rate with low education was relative higher ,which had some relationship to educational level .The residents and the non‐residents infected respectively accouted 71 .43% and 28 .57% ;Blood donors for the first time of HIV infections were 24 cases (68 .57% ) .Blood donors for the second time of HIV infections were 11 cases (31 .43% );Other virus co‐infection respectively were 2 HBV infections ,1 HCV infection and 3 syphilis infections .The route of transmission was mainly through sexual transmission that was mainly heterosexual transmission ,which was 33 cases (94 .58% ) .Conclusion The voluntary blood donors of Shaoguan with HIV is on the rise ,and give priority to with male youths spread through heterosexual sex .It should be pay high attention to by the government ,society and blood stations ,and strengthen the propaganda work of AIDS prevention and control checks ,and minimize the risk of HIV transmission by blood transfusion in or‐der to guarantee the safety of clinical blood transfusion .

8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-456435

RESUMO

A method to determine phytolith-occluded carbon ( PhytOC) was explored. Sodium hydroxide solution was used to dissolve the silicon compound(SiO2 ·nH2O) which occluding on the carbon, and then potassium dichromate-sulphuric acid solution was used to oxidize the released organic carbon. The concentration of Gr3+produced from the reaction was measured by spectrophotometry with its absorbance at 590 nm wavelength. The organic carbon concentration was calculated based on the amounts of potassium dichromate consumed. This analytical method was verified well accuracy and repeatability by running standard addition and recovery experiments. It has the advantages of low carbon loss, easy to operate, low cost;and hardly any influence to body health, as compared with acid dissolution-Elementar Vario MAX CN method. The results obtained from this method have a good correlation with these determined by Elementar Vario MAX CN ( Germany) .

9.
Chongqing Medicine ; (36): 4065-4067,4070, 2014.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-600223

RESUMO

Objective To study the distribution of genotypes of hepatitis C virus in Guizhou and its relationship between infec-tious route of genotype and age ,gender was analyzed .Methods Serum specimens in this study were obtained from 198 patients , whose anti-HCV and HCV RNA were positive .A reverse transcriptase PCR(RT nested-PCR)assay using conserved primers de-duced from the core-envelope 1(C-E1)region of the hepatitis C virus(HCV)genome was employed to amplify a 474-nucleotide-long fragment .Phylogenetic analysis of the C-E1 sequences was conducted by direct sequencing of the RT-PCR products and alignment with published HCV subtypes in GenBank .Subtypes of the samples were determined by nucleotide sequencing followed by composi-tion of a phylogenetic tree .Results Among the 198 patients surveyed ,genotype 1a was detected in 4 cases(2 .0% ) ,genotype 1b in 71 cases(35 .9% ) ,genotype 2a in 9 cases(4 .6% ) ,genotype 3a in 29 cases(14 .7% ) ,genotype 3b in 47 cases(23 .7% ) ,genotype 6 a in 37 cases(18 .7% )and genotype 6d in 1 cases(0 .5% ) .Genotype distribution on gender had no statistical significance(P>0 .05) , and its distribution on people with different ages had statistical significance(P<0 .05) ,and its distribution on patients with different infectious routes was significantly different(P<0 .05) .Conclusion The major genotypes of HCV are 1b ,3b ,6a and 3a in Guizhou , and genotype 1a is predominant .Genotypes 1a ,2a and 6d exist too .Genotypes of patients infected with HCV are related to their in-fectious routes ,and the HCV genotypes are in a great variety .

10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-550344

RESUMO

The antifungal activity of fluconazole and its two derivatives was tested with ketoconazole as a control by the method of cultivation. The preliminary results show that fluconazole had wider antimicrobial spectra and stronger antifungal activities than its two derivatives and ketoconazole.

11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-550461

RESUMO

In order to search for a more potent and less toxic antifungal agent, five novel sulconazole analogues were synthesized by changing 1-imidazolyl and p-chlorobenzyl in sulconazole structure. The results of preliminary biological tests show that analogues Ⅰ and Ⅱ possess more potent antifungal activities and wider antifungal spectra than sulconazole.

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