[Strategy for prevention and control of imported infectious disease]

The process of globalization increases the risk of global transmission of infectious diseases, resulting in pressure for country's prevention and control of imported infectious disease. Based on the risk assessment of disease importation and local transmission, a strategy that conducting importation prevention and routine prevention and control before the importation of disease and taking emergency control measures after the importation of disease was developed. In addition, it is important to take part in global infectious disease response action, aid the countries with outbreak or epidemic to actively decrease the risk of disease importation.

Numerical Study and Experimental Verification of Tissue Cryofreezing Based on Flexible Cryoprobe System

BACKGROUND

Cryosurgery is effectively used for treating various diseases including cancer and tumor. But there is difficulty accurately quantifying the spatial temperature profile needed to determine diseased tissue destruction.

OBJECTIVE

A novel flexible cryosurgical probe was developed that can pass through the natural cavities of human body to minimize the damage to normal tissues. The present study aims to study the design of the flexible cryoprobe by 3D heat transfer modeling and experimental verification.

MATERIALS AND METHODS

A 3D model, on the basis of the flexible cryoprobe system, was developed to predict the temperature distribution during cryosurgery in porcine liver. In vitro experiments and pathological analysis with TUNEL staining of tissue samples were performed for verification.

RESULTS

The results of numerical simulation based on the Pennes equation exhibited good agreement with experimental measurements for the flexible cryoprobe system. The simulation shows that the tissue within the range of 0 to 6 mm along the cryoprobe is effectively destroyed and the temperature in this domain decreases to the range -35°C to -40°C. Due to the non-uniform distribution, the temperature in the z-axis direction decreases to -40°C faster, with more serious tissue damage; whereas the x-axis direction has the greater distance of tissue destruction. Pathologic analysis of tissue after in vitro cryosurgery has verified the efficacy of the flexible cryoprobe system.

CONCLUSION

Numerical simulation and experimental verification demonstrate the efficacy of the flexible cryoprobe system. The 3D heat transfer model can be a valuable tool for optimizing the design of the flexible cryoprobe system.

[Epidemiological characteristics of influenza in Guangdong province, during winter of 2017-2018]

Objective: To understand the epidemiological characteristics of influenza in Guangdong province, during the winter of 2017-2018, to provide evidence for response to the diversity of influenza, in different seasonal patterns. Methods: Data on weekly influenza surveillance from January 2016 to April 2018, were collected in Guangdong. Information on patients with Influenza-like illness (ILI), on influenza virus positive rates and on outbreaks during the winter of 2017 to 2018, was analyzed and compared with those in spring of 2016 and summer of 2017. χ(2) test and Fisher exact test were used. Results: In the above said winter, the average percentage of visits for ILI in 28 hospitals where sentinel surveillance program had been set, was 4.99% (157 235/3 149 656), which was above the level of the same period in the previous five years. The positive rates of influenza virus among samples collected from ILI outpatients and hospitalized cases under severe acute respiratory infection (SARI) were 28.33% (2 137/7 543) and 14.93% (256/1 715), with the proportions of B (Yamagata) as 70.43% (1 505/2 137) and 73.05% (187/256) respectively. A total of 257 influenza outbreaks were reported in the winter period, with 82.49% (212/257) occurred in elementary schools. Cases aged 6-14 years occurred in winter and spring appeared of having higher positive rate than those seen in summer (P<0.05) whereas elderly cases aged 60 and above showed higher positive rate in summer than those in winter and spring two seasons (P<0.05). Conclusions: Epidemiological characteristics of influenza appeared in Guangdong province, during the winter from 2017 to 2018, were correlated to Influenza B (Yamagata). Capacity on the implementation of surveillance programs and on the coverage of vaccination should be improved and increased in order to control influenza in different epidemic seasons, in Guangzhou.

The single nucleotide polymorphism rs700518 is an independent risk factor for metabolic syndrome and benign prostatic hyperplasia (MetS-BPH)

Studies have shown that 48.59% of benign prostate hyperplasia (BPH) is combined with metabolic syndrome (MetS). The mainstream view supports the correlation between MetS and BPH, but the pathogenesis of MetS‐BPH is not fully understood. Four hundred and seventy‐four men, aged 47 years or older, were recruited into this study by consecutive routine physical examination programs, and several parameters were obtained from each participant. Based on the diagnosis of BPH, MetS, and MetS‐BPH, the participants were divided into BPH and Non‐BPH groups, MetS and Non‐MetS groups, as well as MetS‐BPH and Non‐MetS‐BPH groups. The values of the obtained parameters were evaluated using Student's t‐test, chi‐square test, and logistic regression analysis. The value of estradiol (E2) was higher in the diseased groups (BPH, MetS, and MetS‐BPH groups) compared with the corresponding control groups (Non‐BPH, Non‐MetS, and Non‐MetS‐BPH groups), and the differences were statistically significant. Also, E2 had an independent association with BPH (OR = 2.286, 95% CI: 1.723–3.593, p < 0.001), MetS (OR = 1.406, 95% CI: 0.585–2.315, p < 0.001), and MetS‐BPH (OR = 1.249, 95% CI: 0.795–1.962, p < 0.001). Regarding SNPs of CYP19A1 gene, both the rs4646 genotypes (CC, CA, and AA) and the rs700518 genotypes (CC, CT, and TT) were present in every group, and all genotypes had statistically significant differences between the diseased and corresponding control groups. However, only the TT genotype of rs700518 was independently associated with BPH, MetS, and MetS‐BPH after adjusting for age. The TT genotype of rs700518 is an independent risk factor for the MetS‐BPH populations, and the CYP19A1 gene regulation of estrogen leads to MetS‐BPH.

The relationship between the levels and function of endothelial progenitor cells and factor V Leiden and protein C deficiency in patients with primary Budd-Chiari syndrome

OBJECTIVE

Budd-Chiari syndrome (BCS) is a life-threatening hepatic disease characterized by hepatic venous obstruction at the level of hepatic vein, hepatic venules, or inferior vena cava. No evidence reported the relationship between the endothelial progenitor cells and the deficiency of factor V Leiden and protein C in patients with primary Budd-Chiari syndrome.

PATIENTS AND METHODS

We recruited participants between June 2014 and July 2015. For primary BCS group, 28 patients were collected. 20 patients were included in the NAFLD group. Another 73 healthy participants were recruited into the control group. None of the patients and participants had received interventional therapy or had undergone surgery prior to being recruited. Levels and functions of endothelial progenitor cells (EPCs) were examined. The factor V Leiden mutation, protein C deficiency and protein S deficiency were evaluated. Finally, the relationship between the levels and function of endothelial progenitor cells and factor V Leiden and protein C deficiency in patients with primary Budd-Chiari syndrome was analyzed.

RESULTS

The results showed that no significant differences were found between the BCS (and NAFLD) and control group considering age, sex, BMI, smoking (p>0.05 for variables). However, significant differences were observed in TG, TC, HDL-C, white blood cells, hemoglobin, ALT, AST, ALP, γ-GT, total bilirubin, and albumin (p<0.05 for variables). Compared with the healthy participants, significant downregulation was found in BCS and NAFLD patients regarding CD34+/CD45-, late outgrowth endothelial cells (OECs) colonies, OECs proliferation, and OECs tubulogenesis (p<0.001 for variables). Among the 28 BCS patients, factor V Leiden mutation (n=10, 35.71%, OR 12.67, 95% CI 5.24-27.93) and hereditary protein C deficiency (n=4, 14.29%, OR 7.48, 95% CI 2.02-21.43) were more prevalent than those in the control group. These results suggested that factor V Leiden mutation and protein C deficiency were major risk factors for BCS. Finally, we demonstrated that factor V Leiden and protein C deficiency may negatively regulate the OECs levels and functions in BCS patients.

CONCLUSIONS

It's important to improve the OECs levels and functions, and to prevent the deficiency of factor V Leiden and protein C in the treatment of BCS.