Elevated AIP is associated with the prevalence of MAFLD in the US adults: evidence from NHANES 2017-2018.

Background: Atherogenic Index of plasma (AIP) is closely related to metabolic abnormalities. But as of now, there is no definitive conclusion on the dose-response relationship pattern between AIP and metabolic associated fatty liver disease (MAFLD). Objective: The objective of this study was to provide a fresh insight for understanding the intrinsic link between AIP and the prevalence of MAFLD by exploring the dose-response pattern between AIP and MAFLD. Methods: A total of 9254 participants received the survey and 1090 participants were finally included according to the screening criteria. To evaluate the association between AIP and the prevalence of MAFLD based on weighted multivariate logistic regression. Sensitivity analysis of the association between AIP and MAFLD was performed using propensity score matching (PSM). Restrictive cubic splines (RCS) were used to identify patterns of dose-response relationships between AIP and MAFLD, and receiver operator characteristic (ROC) curves were used to evaluate the predictive ability of AIP and traditional lipid parameters for MAFLD. Results: In this study, a total of 563 participants were found to have MAFLD. The results of weighted multivariate logistic regression analysis demonstrated that, after adjusting for sex and age, participants in the highest quartile (Q4) of AIP had a significantly increased risk of developing MAFLD compared to those in the lowest quartile (Q1) (Model 2: OR = 9.03, 95% CI 4.75-17.17). A similar trend was observed in the fully adjusted model (Model 3: OR = 3.85, 95% CI 1.55-9.52). The RCS analysis revealed a linear dose-response association between AIP and MAFLD(P for crude non-linearity = 0.087). This association remained significant after accounting for potential confounding variables(P for adjusted non-linearity = 0.663). The ROC curve results suggest that AIP performs better than traditional lipid indicators in predicting MAFLD (AUC = 0.732, 95%CI 0.705-0.758). Conclusion: A linear dose-response relationship exists between AIP and MAFLD, suggesting that as AIP increases, so does the risk of developing MAFLD.

Radon kinetics in a natural indoor radon chamber.

An unusual 180 m3 storage room in the basement of a two-story laboratory building is unventilated, and separated from occupiable rooms by double steel doors. The space completely borders on soil through the concrete floor and two of its concrete walls. The room also contains a separate inner chamber with 1 m thick concrete walls designed to damp vibrations in the room above it. The space boasts a relatively high radon level, 1083 Bq m-3, which varies with local outdoor environmental conditions. Measurements were made of radon concentrations at various locations and heights within the facility. More than a year of continuous radon concentration data corresponding to a single location are also available, along with measurements of indoor and outdoor pressure, temperature, and humidity. Data were also collected with as many as five fans placed in different locations and cycled on for variable time periods. First order linear kinetic models were created to explain the observed approaches to steady state due to changing conditions and wash-out resulting from intentional ventilation. Results demonstrate a good fit between changes in the radon concentration level and the developed compartmental models. However, no significant differences were observed between radon concentration at different locations or heights in the chamber.

Estimation of radon release rate for an underground uranium mine ventilation shaft in China and radon distribution characteristics.

Radon, known to be a human carcinogen, is one of the most concerned radionuclides in uranium mining which need to be monitored and controlled. A large amount of radon is discharged to the atmosphere mainly through underground ventilation shafts for underground uranium mining. There are many studies on radon release of uranium mine, but the differences of the measured radon results are very big. In this paper, a typical underground uranium mine in China is chosen as a case study. This study finds that distribution of radon concentration and airflow speed inside the ventilation shaft are extremely uneven, but the distributions are respectively stable and regular for a fixed cross-section at the wellhead depth of 0-1 m. There is also a stable numerical relationship between the radon release rate and the product of radon concentration and airflow speed at the center for any cross-section in the shaft. Based on this regulation, a multipoint interpolation-integration method and a one-point method for calculating radon release from underground ventilation shaft are proposed in this paper. The results show that the difference between these two methods is 2-10%, the one-point method is more suitable and convenient to be applied for the long-term monitoring radon release rate from uranium mine ventilation. The research results in this paper can be applied in the estimation of radon release rate for other underground uranium ventilation shafts.

Controlling 212Bi to 212Pb activity concentration ratio in thoron chambers.

It is necessary to establish a reference atmosphere in a thoron chamber containing various ratios of 212Bi to 212Pb activity concentrations (C(212Bi)/C(212Pb)) to simulate typical environmental conditions (e.g., indoor or underground atmospheres). In this study, a novel method was developed for establishing and controlling C(212Bi)/C(212Pb) in a thoron chamber system based on an aging chamber and air recirculation loops which alter the ventilation rate. The effects of main factors on the C(212Bi)/C(212Pb) were explored, and a steady-state theoretical model was derived to calculate the ratio. The results show that the C(212Bi)/C(212Pb) inside the chamber is mainly dependent on ventilation rate. Ratios ranging from 0.33 to 0.83 are available under various ventilation. The stability coefficient of the ratios is better than 7%. The experimental results are close to the theoretical calculated results, which indicates that the model can serve as a guideline for the quantitative control of C(212Bi)/C(212Pb).

Analysis of the saturation phenomena of the neutralization rate of positively charged 218Po in water vapor.

Generally, 88% of the freshly generated 218Po ions decayed from 222Rn are positively charged. These positive ions become neutralized by recombination with negative ions, and the main source of the negative ions is the OH- ions formed by radiolysis of water vapor. However, the neutralization rate of positively charged 218Po versus the square root of the concentration of H2O will be a constant when the concentration of H2O is sufficiently high. Since the electron affinity of the hydroxyl radical formed by water vapor is high, the authors propose that the hydroxyl radical can grab an electron to become OH-. Because the average period of collision with other positively charged ions and the average life of the OH- are much longer than those of the electron, the average concentration of negative ions will grow when the water vapor concentration increases. The authors obtained a model to describe the growth of OH- ions. From this model, it was found that the maximum value of the OH- ion concentration is limited by the square root of the radon concentration. If the radon concentration is invariant, the OH- ion concentration should be approximately a constant when the water vapor concentration is higher than a certain value. The phenomenon that the neutralization rate of positively charged 218Po versus the square root of the water vapor concentration will be saturated when the water vapor concentration is sufficiently high can be explained by this mechanism. This mechanism can be used also to explain the phenomenon that the detection efficiency of a radon monitor based on the electrostatic collection method seems to be constant when the water vapor concentration is high.

[Prevalence of high-risk human papillomavirus and incidence of cervical intraepithelial neoplasia in female populations in Shenzhen, Guangdong Province].

OBJECTIVE: To investigate the prevalence of high-risk human papillomavirus (HPV) and incidence of cervical intraepithelial neoplasia (CIN) in female populations in Shenzhen, Guangdong Province, China. METHODS: Totally 1137 women aged 15-59 from Shahe Community, Nanshan District, Shenzhen were investigated for cervical cancer during an population-based epidemiological screening from November 2004 to December 2004. Visual inspection with acetic acid (VIA), colposcopy, liquid-based cytology test (LCT), and hybrid capture 2 (HC-) were performed to detect the high-risk HPV types in cervical secretions. Biopsy under colposcope was performed in women who were HPV-positive with LCT >or= atypical squamous cells of undetermined sign (ASCUS) or HPV-negative with LCT >or= low grade squamous intraepithelial lesion (LSIL), with the pathological results as the golden standards. RESULTS: The detection rate of high-risk HPV-DNA was 14.0%. HPV detection rates in 15-24, 25-29, 30-34, 35-39, 40-44, 45-49, and 50-59 age groups were 15.5%, 17.7%, 12.6%, 8.8%, 10.2%, 15.3%, and 21.0%, respectively (P < 0.05). HPV detection rates in 25-29 years group and 50-59 years group were significantly higher than those in other groups (P < 0.05) and 35-39 group had the lowest detection rate. The curve of HPV infection rates in all groups was 'V' type. The overall incidence of CIN was 4.4%. The incidences of CIN , CIN , and CIN were 3.2%, 1.0%, and 0.3%, respectively, in which the incidence of CIN was significantly higher than those of CIN and . HPV detection rates increased with cervical lesion grades, which in >or=CIN groups and normal group were 100.0% and 8.3%, respectively. No cervical cancer was identified in this research. The sensitivities of VIA, colposcopy, LCT, and HC-II for high-risk HPV screening were 35.7%, 50.0%, 92.9%,and 100%, respectively, in detecting high-grade squamous intraepithelial lesion (HSIL), the specificities of these four methods were 96.0%, 87.2%, 88.4%, and 86.9%, respectively. Satisfactory negative predictive values were obtained for all methods. CONCLUSIONS: HPV infection is the main risk factor for CIN. Cervical cancer among female populations in Shenzhen is still in early stages. Prevention of HPV infection and treatment of CIN are key for the prevention of cervical cancer.

[Evaluation of gene chip technology for high risk type human papillomavirus in cervical cancer screening].

OBJECTIVE: To investigate the clinical value of gene chips technology for human papillomavirus (HPV) in cervical cancer screening. METHODS: A population-based cross-sectional screening study was conducted among 1137 women aged 15-59 in a community, Shenzhen city. Hybrid capture 2 (hc2) and gene chip technology were performed to examine the high risk type human papillomavirus in the exfoliated cervical cells. Liquid-based cytology test (LCT) was also performed at the same time. The HPV-positive women with LCT > or = atypical squamous cells of undetermined sign (ASCUS) and the HPV-negative women with LCT > or = low grade squamous intraepithelial lesion (LSIL) underwent biopsy under colposcopy. The pathological results were used as the gold standard to evaluate the two HPV test methods. RESULTS: Totally 122 biopsy specimens were obtained. Pathological examination showed no cervical cancer case, 3 cases of grade III cervical intraepithelial neoplasia (CIN), 11 cases of grade II CIN, 36 cases of grade I CIN, 69 cases of chronic cervicitis and metaplasia of squamous epithelium, and 3 cases of normal cervix. The HPV-positive rate was 14.0% by hc2 and 9.8% by gene chips with a HPV-positive rate by hc2 higher than that by gene chips (P < 0.001) and an mediocre accordance rate between these methods (kappa = 0.498). The. HPV-positive rate increased along with the increase of the grade of cervical lesions (P < 0.05). The sensitivity, specificity, accuracy, positive prevalue, negative prevalue, positive likelihood ratio and negative likelihood ratio of hc2 for high-risk HPV were 100%, 87.1%, 87.3%, 8.8%, 100%, 7.7 and 0.000, respectively; and those of gene chips were 78.6%, 91.1%, 90.9%, 9.9%, 99.7%, 8.8 and 0.235 respectively. CONCLUSION: At present hc2 high risk HPV testing is still the better method for cervical cancer screening. Gene chips technology is able to rival hc2 except that its sensitivity for cervical high grade lesions need be improved.

[Distribution of human papillomavirus types in Shenzhen women].

OBJECTIVE: To investigate the status of genital infection as well as distribution of types of human papillomavirus (HPV) in women in Shenzhen and provide population data for the future vaccine intervention on cervical cancer. METHODS: Women with age between 15 and 59 years were selected in cluster stratified sampling from Huaqiaocheng community, Nanshan district, Shenzhen and received a population-based cervical cancer screening. After consent, every woman was interviewed by using questionnaire and tested by liquid-based cytology and HPV DNA (hybrid capture 2 and gene chips typing) separately. RESULTS: Totally 1 137 women were screened. The rate of high risk HPV of hybrid capture 2 test (14. 0% ) was higher than gene chips typing test (9. 8%) (chi(2) = 27. 198, P < 0. 001) ; the consistency of the two tests was acceptable ( kappa = 0. 498, P < 0. 001). The rates of low risk HPV types and other types of gene chips typing test in this population were 1. 9% and 0. 2% respectively. The percentages of HPV 16, 18 and 58 in HPV positive women were 29. 7% , 18. 9% and 18. 9%. The rates of different age group of low risk HPV were 1. 4% (17-34), 1. 7% (35-44) and 3. 2% (45-59) , respectively. CONCLUSIONS: HPV 16, 18, and 58 are the most popular types in the study population. The differences of infection rates of high risk HPV are due primarily to the variation of HPV16 distribution among age-specific population. The chances of being affected by low risk HPV will increase with age.