[Occupational health risk assessment for organic solvent in the major posts of printing industry]

Objective: To evaluate the occupational health risk of organic solvents in major posts of printing industry, and to provide technical reference to take targeted risk control measures. Methods: In January 2021, the contact ratio method was used to assess the occupational health risk of organic solvents in the major posts of 84 printing enterprises in Shantou, and Monte Carto method was used to estimate the probability distribution of risk levels in the majorpostsin January 2021. Results: The highest probability of risk assessment in printing and membranecovering post is Level 4 (high risk) , which are 76.2% and 67.6% respectively; the highest probability of simulation evaluation result in oil blending, dispensing and cleaning post is Level 3 (medium risk) ; and the simulation evaluation result in glueing post are mostly Level 3 (medium risk) and Level 4 (high risk) , the probability of which are 45.7% and 54.3% respectively. Conclusion: The occupational health risk of organic solvents in the major posts is generally middle-high risk level, and then the occupational health risk control of organic solvents in major posts of printing industry should be strengthened.

[Two-dimensional equivalent mechanical modeling and finite element analysis of normal female pelvic floor system]

Objective: To construct the geometric model of the pelvic floor by a two-dimensional equivalent mechanics method, and to explore the effect of the shape and position of pelvic floor organs and tissues on the biomechanical properties of the pelvic floor under different abdominal pressure. Methods: A 28-year-old healthy and symmetrical married infertile female volunteer was included. The pelvic floor tissue was scanned in the supine position using a 3.0T magnetic resonance scanner (Philips Company, Holland). Based on the method of magnetic resonance imaging (MRI) two-dimensional parameter measurement and computer aided design, the geometric model and finite element model of the female pelvic floor were established, and the biomechanical characteristics of the pelvic floor support system under different abdominal pressure were analyzed. Results: In this study, four different working conditions of the pelvic floor force were simulated under 60, 99, 168, and 208 cmH₂O (1 cmH₂O=0.098 kPa) abdominal pressure loads. The trend was as follows: under the abdominal pressure load, the retrograde flexion of the uterus occurred, the cervical, the middle and upper vaginal segment and the levator anus muscle had the characteristic change of mechanical axial direction pointing to the sacrum and coccyx, and the deformation of the levator anus muscle in the horizontal direction was greater than that in the vertical direction. With the increase of the abdominal pressure, the maximum stress values of the pelvic floor whole system of healthy subjects under four different working conditions were 0.194 3, 0.389 6, 0.557 1, and 0.627 5 MPa, respectively, and the maximum displacement values were 10, 14, 21 and 25 mm, respectively. The maximum stress values of the cervical and vaginal middle and upper segment were 0.111 7, 0.161 8, 0.250 6, and 0.304 1 MPa, respectively, and the maximum displacement values were 3, 6, 9, and 11 mm, respectively. The maximum stress of the perineal body was 0.063 4, 0.119 6, 0.235 2, and 0.288 0 MPa, and the maximum displacement was 1, 2, 4, and 5 mm. The maximum stress values of the levator anus muscle were 0.194 3, 0.389 6, 0.557 1, and 0.627 5 MPa, and the maximum displacement values were 2, 4, 7, and 8 mm, respectively. The maximum stress and maximum displacement of pelvic organs increased with the increase of the abdominal pressure under different working conditions. The stress axial relationship of normal female pelvic floor was that the middle and upper segment of uterus and vagina mainly acted on the sacrococcyx and the levator anus muscle, and the lower vaginal segment acts on the perineal body. Conclusions: The two-dimensional equivalent mechanical modeling and finite element analysis of the female pelvic floor system can accurately reflect the biomechanical characteristics of the female pelvic floor, and the resultant stress direction of the pelvic organs points to the sacrum and coccyx. The sacrum and coccyx, levator anus and perineal body play important stress supporting roles in the pelvic floor system.

[Contribution of central motion conduction time to the assessment of corticospinal tract lesions and its clinical significance]

Objective: To investigate the association of central motion conduction time (CMCT) with corticospinal tract lesions and its clinical application. Methods: Patients who completed transcranial magnetic stimulation-motor evoked potentials were included from Department of Neurology, Xuanwu Hospital between June 2020 and June 2021. The differences of CMCT values between corticospinal tract sign-positive group and tendon reflex-positive group and the relevant negative groups were compared. The consistency between increased CMCT values and the positive signs of corticospinal tract damage, as well as the significance of CMCT in different neurological diseases were further evaluated. Results: A total of 271 patients were included in the study, aged 12-86 (49±16) years, with 137 males (50.55%) and 134 females (49.45%). The CMCT values［M（Q₁，Q₃）］from Hoffmann's sign-positive group [9.52 (8.54, 10.99) ms vs 9.03 (8.30, 9.53) ms], Babinski's sign-positive group [19.54 (16.97, 24.43) ms vs 16.85(15.63, 18.55) ms] and tendon reflex-positive group [15.38 (9.27, 19.28) ms vs 10.49(8.79, 16.60) ms] were larger than those of relevant negative groups (all P<0.01). In the Babinski sign-positive group, 78.01%(181/232) of the patients had increased CMCT, while in the Hoffmann's sign-positive group, only 26.03%(19/73) of the patients had increased CMCT, indicating that the contribution of CMCT from the lower extremities to the assessment of corticospinal tract lesions was better than that of the upper extremities. With the increase of CMCT values in lower limbs, Babinski sign positive rate increased, the difference was statistically significant(P<0.001). In nervous system diseases, the consistency between CMCT and pathological signs was 75.65% (205/271). Conclusions: The contribution of CMCT from the lower extremities to the assessment of corticospinal tract lesions is superior to that of upper limbs. The higher increase of CMCT values are more reliable for corticospinal tract damage. CMCT has a good concordance with corticospinal tract lesions in some neurological diseases, which can be used to assist clinical diagnosis.

KI and TEDA influences towards the retention of radiotoxic CH3I by activated carbons

Activated carbons (AC) are widely used within the ventilation networks of nuclear facilities to trap volatile iodine species. In this paper, the performances of various commercial activated carbons towards the trapping of γ-labelled methyl iodide were evaluated in semi-pilot scale under different R.H. according to normalized procedures. A combination between the retention performances and the physico-chemical properties as deduced from several techniques was performed to gain insights about the AC influencing parameters on γ-CH₃I capture. Different trends were obtained depending on the impregnant nature and the studied conditions. A high sensitivity of KI/AC towards water vapor was outlined. At R.H. = 40%. The enhancement of water uptake by KI/AC as deduced from water adsorption experiments, leads to decrease the available microporosity for CH₃I physisorption, inducing therefore the reduction of performances as a function of KI content at these conditions. At R.H. = 90%, the adsorption mechanism was found to be governed by isotopic exchange reaction since 90% of the microporosity was occupied by water molecules. Therefore, a slight increase of DF was obtained in these conditions. This sensitivity was found to be of a lesser extent for TEDA/AC displaying the highest retention performances whatever the studied condition.

Resting heart rate and incident atrial fibrillation: A stratified Mendelian randomization in the AFGen consortium

Background

Both elevated and low resting heart rates are associated with atrial fibrillation (AF), suggesting a U-shaped relationship. However, evidence for a U-shaped causal association between genetically-determined resting heart rate and incident AF is limited. We investigated potential directional changes of the causal association between genetically-determined resting heart rate and incident AF.

Method and results

Seven cohorts of the AFGen consortium contributed data to this meta-analysis. All participants were of European ancestry with known AF status, genotype information, and a heart rate measurement from a baseline electrocardiogram (ECG). Three strata of instrumental variable-free resting heart rate were used to assess possible non-linear associations between genetically-determined resting heart rate and the logarithm of the incident AF hazard rate: <65; 65–75; and >75 beats per minute (bpm). Mendelian randomization analyses using a weighted resting heart rate polygenic risk score were performed for each stratum.

We studied 38,981 individuals (mean age 59±10 years, 54% women) with a mean resting heart rate of 67±11 bpm. During a mean follow-up of 13±5 years, 4,779 (12%) individuals developed AF. A U-shaped association between the resting heart rate and the incident AF-hazard ratio was observed. Genetically-determined resting heart rate was inversely associated with incident AF for instrumental variable-free resting heart rates below 65 bpm (hazard ratio for genetically-determined resting heart rate, 0.96; 95% confidence interval, 0.94–0.99; p = 0.01). Genetically-determined resting heart rate was not associated with incident AF in the other two strata.

Conclusions

For resting heart rates below 65 bpm, our results support an inverse causal association between genetically-determined resting heart rate and incident AF.

Disease Burden and Attributable Risk Factors of Alzheimer's Disease and Dementia in China from 1990 to 2019

BACKGROUND

Updated information on the burden of Alzheimer's disease and other forms of dementia are of great importance for evidence-based health care planning. However, such an estimate has been lacking in Chinese populations at both national and provincial levels.

OBJECTIVE

To estimate the temporal trends and the attributable burdens of selected risk factors of Alzheimer's disease and other forms of dementia in China.

DESIGN, SETTING, AND PARTICIPANTS

This is an observational description of the Global Burden of Diseases Study 2019 (GBD 2019). Data on incidence, mortality, prevalence, disability-adjusted life years (DALYs), years lived with disability (YLDs), and years of life lost (YLLs) of Alzheimer's disease and other forms of dementia were derived from the GBD 2019 study at both national and provincial levels in China.

MEASUREMENTS

Six indicators were used: incidence, mortality, prevalence, DALYs, YLLs, and YLDs. Absolute numbers in detail by age, sex, region, and age-standardized rates (with 95% uncertainty intervals) were calculated.

RESULTS

There were notable increasing trends in the number of deaths (247·9%), incidence (264·8%), prevalence (296·5%), DALYs (228·1%), YLDs (308·7%) and YLLs (201·7%) from 1990 to 2019, respectively. The corresponding age-standardized rates increased by 6·2%, 19·3%, 33·6%, 10·7%, 33·4% and 3·1%. Smoking, high body mass index, high fasting plasma glucose levels, and metabolic risks were the four leading risk factors. Higher burden was observed among females versus males and in the more developed regions.

CONCLUSIONS

The disease burden in China were increasing substantially. Regional differences of the disease burden are accompanied by discrepancies of economic level and geographical location, as well as different levels of exposure to risk factors. Targeted prevention and control strategies are urgently needed to reduce the disease burden.

[Analysis of clinical phenotype and genotype of Chinese children with disorders of sex development]

Objective: To explore the heterogeneity and correlation of clinical phenotypes and genotypes in children with disorders of sex development (DSD). Methods: A retrospective study of 1 235 patients with clinically proposed DSD in 36 pediatric medical institutions across the country from January 2017 to May 2021. After capturing 277 DSD-related candidate genes, second-generation sequencing was performed to analyzed the heterogeneity and correlation combined with clinical phenotypes. Results: Among 1 235 children with clinically proposed DSD, 980 were males and 255 were females of social gender at the time of initial diagnosis with the age ranged from 1 day of age to 17.92 years. A total of 443 children with pathogenic variants were detected through molecular genetic studies, with a positive detection rate of 35.9%. The most common clinical phenotypes were micropenis (455 cases), hypospadias (321 cases), and cryptorchidism (172 cases) and common mutations detected were in SRD5A2 gene (80 cases), AR gene (53 cases) and CYP21A2 gene (44 cases). Among them, the SRD5A2 mutation is the most common in children with simple micropenis and simple hypospadias, while the AMH mutation is the most common in children with simple cryptorchidism. Conclusions: The SRD5A2 mutation is the most common genetic variant in Chinese children with DSD, and micropenis, cryptorchidism, and hypospadias are the most common clinical phenotypes. Molecular diagnosis can provide clues about the biological basis of DSD, and can also guide clinicians to perform specific clinical examinations. Target sequence capture probes and next-generation sequencing technology can provide effective and economical genetic diagnosis for children with DSD.

Effects of pre-incubation storage duration and nonventilation incubation procedure on embryonic physiology and post-hatch chick performance

This study investigated the effects and possible interactions of storage and nonventilation during incubation for eggs from Sasso broiler breeder flock on pre- and post-hatch incubation results.

A total of 1,260 Sasso eggs from a 58-wk-old broiler breeder flock were individually numbered, weighed and stored for 7 d or for 18 d in a climate-controlled room (16°C, 75% RH). After storage, eggs were weighed, and randomly assigned equally into 2 incubators. One of the incubators was ventilated (V) for the entire incubation and the second was nonventilated (NV) for the first 12 d. At d 18, the eggs were weighed, candled, and fertile eggs were transferred from the turning trays to hatching baskets. During the last 3 d of incubation, hatching eggs were checked individually every 3 h for hatching events and hatchability of fertile eggs. After pull out at d 21.5, post-hatch performances was determined until 1 wk of age.

Results showed that, embryo weights from eggs in NV incubator was significantly higher (P < 0.05) in both stored eggs compared to those from eggs in ventilated incubator, but embryos from eggs stored for 18 d were smaller (P < 0.05) than those from eggs stored for 7 d. Hatchability was higher (P < 0.0001) in NV incubator compared to V incubator in both 7 d and 18 d stored eggs and an interaction was found between incubation ventilation and storage duration on both hatchability and embryonic mortality (P < 0.0001). Chick weights from NV incubator at 7 d post-hatch was greater (P = 0.0009) than those from V incubator. Serum Tri-iodothyronine (T₃) and Thyroxin (T₄) concentrations were significantly higher (P < 0.05) in NV compare to V group.

It was concluded that the effect of long-term pre-incubation storage on embryonic physiology and post-hatch growth interacted significantly with incubation ventilation and that nonventilation can compensate for the negative effects of storage on some hatching and post-hatch performances.

[Bone damage in osteoporotic fractures]

Osteoporotic fracture is fundamentally different from traumatic fracture. It is a pathological fracture based on the skeletal system in the state of osteoporosis, and the essence of its lesion is the decline of bone strength. Bone strength is influenced by a variety of factors, including the material properties and tissue structure of the bone, as well as muscle load. The pathological changes of osteoporotic fracture both of the damage of bone mass and bone quality. After the occurrence of osteoporotic fracture, even successful surgical treatment cannot prevent the further aggravation of osteoporotic bone damage. In this paper, the material properties and tissue structure damage of osteoporotic fractures are elaborated, and it is emphasized to clarify and pay attention to these bone lesions and their risks. Anti-osteoporosis treatment is of great importance to improve the clinical efficacy of osteoporosis and fracture intervention and prevent the occurrence of re-fractures.

A bibliometric review of peripartum cardiomyopathy compared to other cardiomyopathies using artificial intelligence and machine learning

As developments in artificial intelligence and machine learning become more widespread in healthcare, their potential to transform clinical outcomes also increases. Peripartum cardiomyopathy is a rare and poorly-characterised condition that presents as heart failure in the last trimester prior to delivery or within 5-6 months postpartum. The lack of a definitive understanding of the molecular causes and clinical progress of this condition suggests that bibliometrics will be well-suited to creating new insights into this serious clinical problem. We examine similarities and differences between peripartum and its closely related familial dilated cardiomyopathy and idiopathic dilated cardiomyopathy. Using PubMed as the source of bibliometric data, we apply artificial intelligence-supported natural language processing to compare extracted data and genes association with these cardiomyopathies. Gene data were enhanced with additional metadata from third-party datasets and then analysed for their impact and specificity for peripartum cardiomyopathy. Artificial intelligence identified 14 genes that distinguished peripartum from both dilated and familial dilated cardiomyopathy. They are as follows: CTSD, RLN2, MMP23B*, SLC17A5, ST2*, PTHLH, CFH*, CFI, GPT, MR1, Rln1, SRI, STAT5A* and THBD. We then used the Human Protein Atlas website that uses affinity-purified rabbit polyclonal antibodies to identify genes that are expressed at the protein level (bold), or as RNA transcripts (*) in healthy human left ventricles. Additional analysis focussed on the full set of peripartum genes on linkage and specificity to cardiomyopathy yielded a different set of thirteen genes (bold font indicates those expressed in cardiomyocytes: PRL, RLN2, PLN, ST2, CTSD, F2, ACE, STAT3, TTN, SPP1, LGALS3, miR-146a, GNB3, SRI). This type of analysis can highlight new avenues for research, aimed at improving genomics-driven peripartum cardiomyopathy diagnosis as well as potential pathological and clinical sub-classification. We expect that this will allow for future improvements in identification, treatment and management of this condition. The first step in the application of these bibliometric-based artificial intelligence methods is to understand the current knowledge, and it is the aim of this paper to show how this might be achieved.

Novel role of estrogen receptor-α on regulating chondrocyte phenotype and response to mechanical loading

OBJECTIVE

In knee cartilage from patients with osteoarthritis (OA), both preserved cartilage and damaged cartilage are observed. In this study, we aim to compare preserved with damaged cartilage to identify the molecule(s) that may be responsible for the mechanical loading-induced differences within cartilage degradation.

METHODS

Preserved and damaged cartilage were harvested from the same OA knee joint. RNA Sequencing was performed to examine the transcriptomic differences between preserved and damaged cartilage cells. Estrogen receptor-α (ERα) was identified, and its function of was tested through gene knockin and knockout. The role of ERα in mediating chondrocyte response to mechanical loading was examined via compression of chondrocyte-laded hydrogel in a strain-controlled manner. Findings from the studies on human samples were verified in animal models.

RESULTS

Level of estrogen receptor α (ERα) was significantly reduced in damaged cartilage compared to preserved cartilage, which were observed in both human and mice samples. Knockdown of ESR1, the gene encoding ERα, resulted in an upregulation of senescence- and OA-relevant markers in chondrocytes. Conversely, knockin of ESR1 partially reversed the osteoarthritic and senescent phenotype of OA chondrocytes. Using a three-dimensional (3D) culture model, we demonstrated that mechanical overload significantly suppressed ERα level in chondrocytes with concomitant upregulation of osteoarthritic phenotype. When ESR1 expression was suppressed, mechanical loading enhanced hypertrophic and osteogenic transition.

CONCLUSION

Our study demonstrates a new estrogen-independent role of ERα in mediating chondrocyte phenotype and its response to mechanical loading, and suggests that enhancing ERα level may represent a new method to treat osteoarthritis.