[Analysis of influenza vaccination status and immunization strategy in high-risk population]

Influenza is a contagious respiratory disease caused by influenza viruses, and the burden of severe disease is commonly seen in high risk populations. Influenza vaccination is an effective way to prevent influenza and its complications, especially for high risk populations. Although some countries have included influenza vaccine in their national immunization programs, influenza vaccination rates remain low globally in high risk populations. The influenza vaccine in China is still a non-immunization program vaccine that is voluntarily vaccinated at its own expense, and the influenza vaccine immunization strategy is different across the country. There is still a gap between the vaccination rate of the influenza vaccine and that of developed countries. It is an urgent problem to further optimize the whole population immunization strategy of influenza vaccine in China, strengthen the publicity of the whole population immunization strategy of influenza vaccine, and reduce the disease burden of influenza in China.

[Analysis of China's influenza vaccination policy based on the model of "behavioural and social drivers of vaccination"]

This article uses the "behavioural and social drivers of vaccination" model released by the World Health Organization (WHO) in 2022 to analyze influenza vaccine policy documents issued by the state and governments. This indicates that the current influenza vaccination policy in China has paid some attention to "publicity and mobilization", but it still pays insufficient attention to "vaccination convenience". It is recommended to continue to strengthen publicity and mobilization, explore ways to improve the convenience of vaccination, formulate corresponding plans to improve the convenience of vaccination, scientifically set vaccination rate targets, and encourage areas with conditions to carry out free vaccination projects for key populations.

[Adult vaccination immunization strategies and research progress worldwide]

Vaccination is the most cost-effective measure to prevent infectious diseases in both children and adults. At present, the global burden of infectious diseases in adults is still heavy. With the continuous development and improvement of vaccines, vaccination has shown great potential to prevent infectious diseases, further reduce the morbidity and mortality of infectious diseases in adults and improve people's life quality. This article summarizes the current status of adult immunization, immunization strategies of representative countries, different adult vaccination strategies, and the advantages and challenges of adult immunization to provide reference for further exploring adult immunization strategies and improving adult vaccination recommendations. More attention should be paid to the immunization strategies for different adult populations, and effective measures should be taken to improve the vaccination coverage for the better protection of people's life and health.

Multiscale Mathematical Analysis of Influencing Factors and Experimental Verification of Microcrack Self-Healing Efficiency of Bitumen Composites Using Microcapsules

The preparation and application of microcapsules containing healing agents have become a crucial way to enhance the self-healing capability of bitumen. This intelligent material has become a hot topic in the field of pavement material and has greatly stimulated the development and applications of pavement engineering. However, there has been no research focused on the relationship of the multistructures from the viewpoint of molecular-size, microsize, and macrosize, which significantly limits the predictions of the self-healing efficiency and structure design of this self-healing material. The purpose of this study was to make a mathematical analysis of the influencing factors of self-healing efficiency based on the self-healing mechanism of bitumen using microcapsules, fully considering the structural dimensions, preparation conditions, and self-healing conditions. In the mathematical analysis, the cross-linking degree of the shell material molecules of the microcapsules was considered for its damage strength from the perspective of molecular structure. The final tip stress of the microcrack was believed to be equal to the puncture strength of the microcapsules in terms of microsize. From a macroscale point of view, the amount of healing agent released from the microcapsule rupture was considered more significant than or equal to the volume of the microcracks. At the same time, the time-temperature superposition principle was applied to simplify the influence factors. The above derivation based on multiscale structures found that the additive amount of the microcapsules, temperature, and time were the three main influencing factors on the self-healing features of bitumen. Finally, the experimental data was investigated considering the three factors, which thoroughly verified the feasibility of the derivation. All results will help to establish a bridge between the initial structural design of self-healing bitumen and the prediction of the final self-healing effects.

Investigation of Asphalt Self-Healing Capability Using Microvasculars Containing Rejuvenator: Effects of Microvascular Content, Self-Healing Time and Temperature

The oily rejuvenator acted as the healing agent in microvasculars. A tensile test was designed to evaluate the self-healing efficiency of asphalt affected by microvascular number, self-healing time and temperature. It was found that the healing agent was slowly released through the microporous channels on the inner shell of the microvascular. The release modes of the agent can work together to improve the self-healing efficiency. The self-healing values of the three samples (asphalt, asphalt/microvasculars without rejuvenator and asphalt/microvasculars with rejuvenator) are 51%, 53%, and 71%. The self-healing capability of the asphalt samples with a healing agent is much greater than that of the other two without a healing agent at the same time. More microvascular rupture at the asphalt sample interface led to a higher self-healing efficiency. The self-healing efficiency values of the three samples (asphalt samples with one, two, and three microvasculars) are 52%, 67%, and 73%, respectively. The self-healing efficiency of the same sample increased during 1-3 days from 26% to 88% in one self-healing cycle. The self-healing efficiency value indicated that increasing the temperature improved each sample's self-healing efficiency. The above trend of change also applies to the second self-healing process. A higher temperature reduces the resistance to molecular motion and accelerates the molecular action of bitumen and the healing agent. The time-temperature equivalence principle can be fully applied to comprehend asphalt self-healing.

Microbial-induced calcium carbonate precipitation: Influencing factors, nucleation pathways, and application in waste water remediation

Microbial-induced calcium carbonate precipitation (MICP) is a technique that uses the metabolic action of microorganisms to produce CO₃^2- which combines with free Ca²⁺ to form CaCO₃ precipitation. It has gained widespread attention in water treatment, aimed with the advantages of simultaneous removal of multiple pollutants, environmental protection, and ecological sustainability. This article reviewed the mechanism of MICP at both intra- and extra-cellular levels. It summarized the parameters affecting the MICP process in terms of bacterial concentration, ambient temperature, etc. The current status of MICP application in practical engineering is discussed. Based on this, the current technical difficulties faced in the use of MICP technology were outlined, and future research directions for MICP technology were highlighted. This review helps to improve the design of existing water treatment facilities for the simultaneous removal of multiple pollutants using the MICP and provides theoretical reference and innovative thinking for related research.

[Research progress of influenza vaccination, pneumococcal vaccination and COVID-19 vaccination among cancer patients]

This article reviews the relevant studies on the efficacy and safety of influenza, pneumococcal and COVID-19 vaccination among tumor patients worldwide in recent years. By combing and analyzing the retrieved literature, the results show that influenza and pneumococcal vaccination can significantly reduce the morbidity and hospitalization rate of infectious diseases in tumor patients, reduce the risk of cardiovascular events and death, and significantly improve survival prognosis. COVID-19 vaccination can also protect tumor patients, especially those who have completed full dose vaccination. Authoritative guidelines and consensuses worldwide all recommend that tumor patients receive influenza, pneumococcal and COVID-19 vaccines. We should carry out relevant researches, as well as take effective measures to strengthen patient education, so that tumor patients can fully experience the health protection brought by the vaccine to this specific group.

A mechanistic review on aerobic denitrification for nitrogen removal in water treatment

The traditional biological nitrogen removal technology consists of two steps: nitrification by autotrophs in aerobic circumstances and denitrification by heterotrophs in anaerobic situations; however, this technology requires a huge area and stringent environmental conditions. Researchers reached the conclusion that the denitrification process could also be carried out in aerobic circumstances with the discovery of aerobic denitrification. The aerobic denitrification process is carried out by aerobic denitrifying bacteria (ADB), most of which are heterotrophic bacteria that can metabolize various forms of nitrogen compounds under aerobic conditions and directly convert ammonia nitrogen to N₂ for discharge from the system. Despite the fact that there is no universal agreement on the mechanism of aerobic denitrification, this article reviewed four current explanations for the denitrification mechanism of ADB, including the microenvironment theory, theory of enzyme, electron transport bottlenecks theory, and omics study, and summarized the parameters affecting the denitrification efficiency of ADB in terms of carbon source, temperature, dissolved oxygen (DO), and pH. It also discussed the current status of the application of aerobic denitrification in practical processes. Following the review, the difficulties of present aerobic denitrification technology are outlined and future research options are highlighted. This review may help to improve the design of current wastewater treatment facilities by utilizing ADB for effective nitrogen removal and provide the engineers with relevant references.

[Progress in research of influenza vaccine and 23 valent pneumococcal polysaccharide vaccine immunization in patients with chronic obstructive pulmonary disease]

A comprehensive review of the research of the effectiveness of influenza vaccine and 23 valent pneumococcal polysaccharide vaccine (PPV23) in patients with chronic obstructive pulmonary disease (COPD) both at home and abroad in recent years showed that influenza vaccine and PPV23 immunization can significantly reduce the risk for influenza and pneumonia in COPD patients, and reduce the acute exacerbation of disease and related hospitalization. In particular, the influenza vaccination can also reduce the risk for ischemic heart disease, acute coronary syndrome, ventricular arrhythmia, lung cancer, dementia and death in the patients, and the immunization of both vaccines has a more significant protective effect. It is recommended by authoritative guidelines both at home and abroad that COPD patients can receive influenza vaccine and PPV23. At present, the coverage of domestic influenza and pneumococcal vaccines are low, and there are less studies in the applications of both vaccines in patients with COPD. Effective measures should be taken to strengthen the health education and increase the vaccination coverage. Additionally, the clinical research of influenza vaccine and PPV23 for COPD patients, especially the analysis on clinical benefit of immunization of both vaccines, should be further strengthened to effectively improve the survival and prognosis of COPD patients.

[Analysis of China's influenza vaccine application policy based on the macro model of the health system]

This article uses the analysis framework of the macro model of the health system to analyze the influenza vaccine policy documents issued by the state and governments at all levels from three perspectives: structure, process and results, and provides a scientific basis for improving the application strategy of influenza vaccine. It is suggested that on the basis of continuing to strengthen publicity, mobilization and organizational guarantee, measures to promote the application of influenza vaccine in China by exploring multi-channel financing mechanisms, combining the experience of new crown vaccination to improve the convenience of influenza vaccination, and scientifically setting vaccination rate targets, improve preparedness for an influenza pandemic.

[SWOT analysis of influenza vaccination promotion of primary care staff based on the perspective of the supplier, customer, and management]

Objective: To analyze the situation of influenza vaccination among primary healthcare workers, find out the problems, and explore the strategies and measures to promote influenza vaccination among grass-roots medical staff. Methods: From April to May 2021, key insider interviews and literature research were carried out based on the perspectives of influenza vaccine suppliers (influenza vaccine manufacturers), consumers (primary medical institutions and primary healthcare workers), and managers (governments at all levels, health administrative departments and disease prevention and control departments). The SWOT (strengths, weaknesses, opportunities, and threats) analysis technique was used to comprehensively evaluate the current situation of influenza vaccination among grass-roots healthcare workers, and a SWOT analysis matrix was established. Results: Influenza vaccination of grass-roots healthcare workers have advantages and opportunities, including primary medical and health institutions' vital influenza vaccination accessibility, influenza vaccine safety is higher, COVID-19 outbreak improves the public awareness of respiratory infectious diseases and vaccine production enthusiasm, coronavirus vaccination has strengthened the capacity of the vaccine distribution system. There are also disadvantages and threats such as the high price of influenza vaccine, insufficient supply, low awareness of influenza vaccine vaccination among grass-roots healthcare workers, lack of demand assessment mechanism on influenza vaccine, poor vaccine deployment, structural imbalance in vaccine supply in different areas, and severe vaccine waste. SWOT analysis matrix of the influenza vaccination status of grass-roots healthcare workers was established, forming dominant opportunity (SO) strategy, dominant threat (ST) strategy, inferior opportunity (WO) strategy, and inferior threat (WT) strategy. Conclusion: Measures should be taken by the supplier, the demand-side, and the management side to improve the influenza vaccine coverage rate of primary healthcare workers, but the emphasis should be on the coordination and management of the management side.

[Progress in research of safety, efficiency and vaccination status of influenza vaccine in populations at high risk]

This paper reviews the domestic and foreign studies published in 2020 on the application of influenza vaccine in populations at high risk. The importance of influenza vaccination in population at high risk has been proved by larger sample, multicentre, high-quality evidence-based studies. Influenza vaccination is the most cost-effective measure to prevent influenza. However, the coverage rate of influenza vaccine is very low in China, it is necessary to strengthen the health education to promote influenza vaccination in different populations. It is recommended to give influenza vaccination to the population in whom influenza vaccination has been proven safe and effective before influenza season. Research of the safety, efficiency and cost-effectiveness of influenza vaccine should be accelerated for the populations in whom such data are lacking or insufficient.

[Evaluation of safety of two inactivated COVID-19 vaccines in a large-scale emergency use]

Objective: To evaluate the safety of two inactivated COVID-19 vaccines in a large-scale emergency use. Methods: Based on the "Vaccination Information Collection System", the incidence data of adverse reactions in the population vaccinated with the inactivated COVID-19 vaccines developed by Beijing Institute of Biological Products Co., Ltd and Wuhan Institute of Biological Products Co., Ltd, respectively, in emergency use were collected, and the relevant information were analyzed with descriptive epidemiological and statistical methods. Results: By December 1, 2020, the vaccination information of 519 543 individuals had been collected. The overall incidence rate of adverse reactions was 1.06%, the incidence rate of systemic adverse reactions was 0.69% and the incidence rate of local adverse reactions was 0.37%. The main systemic adverse reactions included fatigue, headache, fever, cough and loss of appetite with the incidence rates of 0.21%, 0.14%, 0.06%, 0.05% and 0.05%, respectively; the main local adverse reactions were injection site pain and injection site swelling with the incidence rates of 0.24% and 0.05%, respectively. Conclusion: The two inactivated COVID-19 vaccines by Beijing Institute of Biological Products Co., Ltd and Wuhan Institute of Biological Products Co., Ltd showed that in the large-scale emergency use, the incidence rate of general reactions was low and no serious adverse reactions were observed after the vaccinations, demonstrating that the vaccines have good safety.

Microstructure and Properties of Self-Assembly Graphene Microcapsules: Effect of the pH Value

Graphene has attracted attention in the material field of functional microcapsules because of its excellent characteristics. The content and state of graphene in shells are critical for the properties of microcapsules, which are greatly affected by the charge adsorption equilibrium. The aim of this work was to investigate the effect of pH value on the microstructure and properties of self-assembly graphene microcapsules in regard to chemical engineering. Microcapsule samples were prepared containing liquid paraffin by a self-assembly polymerization method with graphene/organic hybrid shells. The morphology, average size and shell thickness parameters were investigated for five microcapsule samples fabricated under pH values of 3, 4, 5, 6 and 7. The existence and state of graphene in dry microcapsule samples were analyzed by using methods of scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). Fourier Transform Infrared Spectoscopy (FT-IR) and Energy Dispersive Spectrometer (EDS) were applied to analyze the graphene content in shells. These results proved that graphene had existed in shells and the pH values greatly influenced the graphene deposition on shells. It was found that the microcapsule sample fabricated under pH = 5 experienced the largest graphene deposited on shells with the help of macromolecules entanglement and electrostatic adherence. This microcapsules sample had enhanced thermal stability and larger thermal conductivity because of additional graphene in shells. Nanoindentation tests showed this sample had the capability of deforming resistance under pressure coming from the composite structure of graphene/polymer structure. Moreover, more graphene decreased the penetrability of core material out of microcapsule shells.

Kinetic analysis of simultaneous denitrification and biomineralization of novel Acinetobacter sp. CN86

A novel aerobic denitrification and biomineralization strain CN86 was isolated from the Qu Jiang artificial lake. Based on phylogenetic characteristics, the isolated strain was identified as Acinetobacter species. Strain CN86 was confirmed to have the ability to perform simultaneous denitrification and biomineralization. Exponential decay equation was used for the matching of kinetic processes on denitrification and biomineralization. A highest nitrate removal rate was achieved at the pH7.0, organic concentration of 1.5g/L and temperature of 30°C. An optimal hardness removal rate was obtained at the pH9.0, organic concentration of 2.0g/L and temperature of 30°C. Strain CN86 is a suitable candidate for the simultaneous removal of nitrate and hardness in groundwater treatment.

Effect of nitrate concentration, pH, and hydraulic retention time on autotrophic denitrification efficiency with Fe(II) and Mn(II) as electron donors

The role of electron donors (Fe(2+) and Mn(2+)) in the autotrophic denitrification of contaminated groundwater by bacterial strain SY6 was characterized based on empirical laboratory-scale analysis. Strain SY6 can utilize Fe(2+) more efficiently than Mn(2+) as an electron donor. This study has shown that the highest nitrate removal ratio, observed with Fe(2+) as the electron donor, was approximately 88.89%. An immobilized biological filter reactor was tested by using three levels of influent nitrate (10, 30, and 50 mg/L), three pH levels (6, 7, and 8), and three levels of hydraulic retention time (HRT; 6, 8, and 12 h), respectively. An optimal nitrate removal ratio of about 95% was achieved at pH 6.0 using a nitrate concentration of 50 mg/L and HRT of 12 h with Fe(2+) as an electron donor. The study showed that 90% of Fe(2+) and 75.52% removal of Mn(2+) were achieved at pH 8.0 with a nitrate concentration of 50 mg/L and a HRT of 12 h. Removal ratio of Fe(2+) and Mn(2+) is higher with higher influent nitrate and HRT. A weakly alkaline environment assisted the removal of Fe(2+) and Mn(2+).

Denitrification characteristics of a newly isolated indigenous aerobic denitrifying bacterium under oligotrophic conditions

A novel indigenous bacterium, strain JM10, isolated from the oligotrophic Hei He reservoir was characterized and showed aerobic denitrification ability. JM10 was identified as Bacillus sp. by phylogenetic analysis of its 16S rRNA gene sequence. Strain JM10 displayed very high levels of activity in aerobic conditions, consuming over 94.3% NO3(-)-N (approximately 3.06 mg L(-1)) with a maximum reduction rate of 0.108 mg NO3(-)-N L(-1) h(-1). Full-factorial Box-Behnken design and response surface methodology were employed to investigate the optimal nitrate degradation conditions. The optimum conditions for nitrate degradation, at a rate of 0.140 mg L(-1) h(-1), were found to be an inoculum size of 16.3% v/v, initial pH of 7.6, C/N ratio of 7.4, and temperature of 27.4 °C, and the C/N ratio and temperature had the largest effect on the nitrate degradation rate. Strain JM10 was added into the water samples from Hei He reservoir and the total nitrogen and nitrate removal rates of the strain reached 66.5% and 100%, respectively. Therefore, our results demonstrate that the strain JM10 favored the bioremediation of the oligotrophic reservoir.

Risk factors for clopidogrel resistance in patients with ischemic cerebral infarction and the correlation with ABCB1 gene rs1045642 polymorphism

The aim of the present study was to examine clopidogrel resistance (CR) in patients with ischemic cerebral infarction and its potential association with a single nucleotide polymorphism (SNP; rs1045642) in the ABCB1 gene. Patients with ischemic cerebral infarction received clopidogrel (75 mg/day) for 7 days and were then subjected to a turbidimetric assay to determine platelet aggregation. Patients were then divided into a CR group and a clopidogrel-sensitive (CS) group. Demographic and clinical data between the two groups were compared. Multivariate logistic regression analysis was performed to determine independent risk factors of CR. PCR products were sequenced to assess ABCB1 rs1045642 SNP genotype and allele frequencies in each group. In total, 303 patients were enrolled in the study; this included 51 CR cases (16.83%) and 252 CS cases (83.17%). Several parameters, including hypertension, diabetes, calcium channel blocker (CCB), β-receptor blocking agent and proton pump inhibitor use, and creatinine, fasting blood glucose, homocysteine (HCY), high-sensitivity C-reactive protein (hs-CRP) and triglyceride levels were significantly higher in the CR group than in the CS group. Diabetes, hs-CRP-increased use of CCBs, and use of β-blockers were found to be independent risk factors for CR. However, ABCB1 gene rs1045642 polymorphism was not found to be an independent risk factor for CR. In conclusion, CR in ischemic stroke patients is associated with several independent risk factors, including diabetes, hs-CRP-increased use of CCBs, and use of β-blockers. However, ABCB1 gene rs1045642 polymorphism has no correlation with CR.

Enhanced ozonation degradation of di-n-butyl phthalate by zero-valent zinc in aqueous solution: performance and mechanism

Enhanced ozonation degradation of di-n-butyl phthalate (DBP) by zero-valent zinc (ZVZ) has been investigated using a semi-continuous reactor in aqueous solution. The results indicated that the combination of ozone (O3) and ZVZ showed an obvious synergetic effect, i.e. an improvement of 54.8% on DBP degradation was obtained by the O3/ZVZ process after 10min reaction compared to the cumulative effect of O3 alone and O2/ZVZ. The degradation efficiency of DBP increased gradually with the increase of ZVZ dosage, enhanced as solution pH increasing from 2.0 to 10.0, and more amount of DBP was degraded with the initial concentration of DBP arising from 0.5 to 2.0mgL(-1). Recycling use of ZVZ resulted in the enhancement of DBP degradation, because the newly formed zinc oxide took part in the reaction. The mechanism investigation demonstrated that the enhancement effect was attributed to the introduction of ZVZ, which could promote the utilization of O3, enhance the formation of superoxide radical by reducing O2 via one-electron transfer, accelerate the production of hydrogen peroxide and the generation of hydroxyl radical. Additionally, the newly formed zinc oxide on ZVZ surface also contributed to the enhancement of DBP degradation in the recycling use of ZVZ. Most importantly, the O3/ZVZ process was also effective in enhanced ozonation degradation of DBP under the background of actual waters.

Excitons emissions and Raman scattering of ZnO nanoparticles embedded in BaF2 matrices by reactive magnetron sputtering

ZnO nanoparticles embedded in BaF2 matrix were fabricated by rf magnetic sputtering technology. The optical properties of high quality ZnO nanoparticles, thermally post treated in a N2 atmosphere, were investigated by temperature-dependence photoluminescence measurement. Free exciton and localized exciton were observed at the low temperature. Free exciton peak was at 3.374 eV and localized exciton peak was at 3.420 eV, dominating the PL spectrum at 77 K. Free exciton transition was observed at 3.310 eV at room temperature, whereas the localized exciton transition was at 3.378 eV. The multiple-phonon Raman scattering spectrum showed that ZnO nanoparticles embedded in BaF2 matrix had a large deformation energy originated from lattice mismatch between ZnO and BaF2 matrix. Analysis of the fitting results from the temperature dependence of FWHM of ZnO exciton illustrated that the large value of gamma(ph) was good qualitative agreement with the large deformation potential.

Molecular Analysis and Prenatal Prediction of Spinal Muscular Atrophy in Chinese Patients by the Combination of Restriction Fragment Length Polymorphism Analysis, Denaturing High-Performance Liquid Chromatography, and Linkage Analysis

BACKGROUND

The difficulties and incurability of spinal muscular atrophy (SMA) highlight the importance of prenatal diagnosis in families with SMA. However, the system applied in prenatal screening is far from perfect.

OBJECTIVES

To optimize the molecular assays and establish a relatively perfect system for prenatal screening. Design, Setting, and Patients A total of 87 patients and 132 parents from 77 families with SMA were screened for SMN1 mutations. Prenatal prediction was performed for 11 fetuses from 10 families with SMA. All of the samples to be tested were from the Department of Neurology, First Affiliated Hospital, Fujian Medical University, Fuzhou, China.

MAIN OUTCOME MEASURES

All of the 87 patients and their parents were screened for SMN1 deletion by restriction fragment length polymorphism analysis and denaturing high-performance liquid chromatography (DHPLC). For those patients without the SMN1 deletion, the SMN1 copy numbers were detected by real-time fluorescence quantitative polymerase chain reaction and the subtle mutations of SMN were screened by direct sequencing. Prenatal prediction was performed by restriction fragment length polymorphism analysis, DHPLC, and linkage analysis for 11 fetuses. Furthermore, the SMN1 copy numbers and detected carriers of SMA were found by DHPLC and real-time fluorescence quantitative polymerase chain reaction in 14 parents and the fetuses without the SMN1 deletion. Results in aborted fetuses and born babies were reconfirmed by restriction fragment length polymorphism analysis and DHPLC. The born babies were followed up and physically examined twice a year.

RESULTS

The frequency of the SMN1 deletion we detected was 93.5% (72 of 77 patients). No subtle mutations were detected in the other 5 families. Four fetuses had the SMN1 deletion and were aborted. The other 7 fetuses, 4 carriers and 3 normal individuals, were born under suggestion by the physician. Fourteen parents were carriers. The reconfirmation of results in the aborted fetuses and born babies was completely consistent with prenatal prediction. The 7 born babies were followed up until recently and all were normal.

CONCLUSIONS

The molecular diagnosis system based on restriction fragment length polymorphism analysis, DHPLC, and linkage analysis is an efficient and accurate method that is well suited for routine use in clinical laboratories.

Protection against hepatic ischemia-reperfusion injury in rats by oral pretreatment with quercetin

OBJECTIVE

To investigate the possible protection provided by oral quercetin pretreatment against hepatic ischemia-reperfusion injury in rats.

METHODS

The quercetin (0.13 mmol/kg) was orally administrated in 50 min prior to hepatic ischemia-reperfusion injury. Ascorbic acid was also similarly administered. The hepatic content of quercetin was assayed by high performance liquid chromatography (HPLC). Plasma glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT) activities and malondialdehyde (MDA) concentration were measured as markers of hepatic ischemia-reperfusion injury. Meanwhile, hepatic content of glutathione (GSH), activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and xanthine oxidase (XO), total antioxidant capacity (TAOC), contents of reactive oxygen species (ROS) and MDA, DNA fragmentation were also determined.

RESULTS

Hepatic content of quercetin after intragastric administration of quercetin was increased significantly. The increases in plasma GPT, GOT activities and MDA concentration after hepatic ischemia-reperfusion injury were reduced significantly by pretreatment with quercetin. Hepatic content of GSH and activities of SOD, GSH-Px and TAOC were restored remarkably while the ROS and MDA contents were significantly diminished by quercetin pretreatment after ischemia-reperfusion injury. However, quercetin pretreatment did not reduce significantly hepatic XO activity and DNA fragmentation. Ascorbic acid pretreatment had also protective effects against hepatic ischemia-reperfusion injury by restoring hepatic content of GSH, TAOC and diminishing ROS and MDA formation and DNA fragmentation.

CONCLUSION

It is indicated that quercetin can protect the liver against ischemia-reperfusion injury after oral pretreatment and the underlying mechanism is associated with improved hepatic antioxidant capacity.

Survey of Salmonellae in mesenteric lymph nodes, gallbladder wall and jejunum from healthy pigs slaughtered in Taiwan

A study made in Taiwan showed that 23.3 per cent of healthy slaughter pigs were infected with salmonellae. Samples of gallbladder wall/liver, mesenteric lymph nodes and jejunum wall were found to yield salmonellae in 16.4, 5.2 and 11.6 per cent of cases respectively. Salmonellae isolated belonged to nine different serotypes, S. london being the serotype most frequently isolated (26.8%) followed by S. anatum, S. panama (16.1% each) and S. typhimurium (12.5%). Of the total number of salmonellae isolated 68.5 per cent were detected simultaneously on brilliant-green phenol-red lactose sucrose agar (BGA) and desoxycholate agar (DCA), whilst 18.5 per cent were detected only on DCA and 13 per cent only on BGA plates.