Gut bacterial and fungal dysbiosis in tuberculosis patients

BACKGROUND

Recent studies have more focused on gut microbial alteration in tuberculosis (TB) patients. However, no detailed study on gut fungi modification has been reported till now. So, current research explores the characteristics of gut microbiota (bacteria)- and mycobiota (fungi)-dysbiosis in TB patients and also assesses the correlation between the gut microbiome and serum cytokines. It may help to screen the potential diagnostic biomarker for TB.

RESULTS

The results show that the alpha diversity of the gut microbiome (including bacteria and fungi) decreased and altered the gut microbiome composition of TB patients. The bacterial genera Bacteroides and Prevotella were significantly increased, and Blautia and Bifidobacterium decreased in the TB patients group. The fungi genus Saccharomyces was increased while decreased levels of Aspergillus in TB patients. It indicates that gut microbial equilibrium between bacteria and fungi has been altered in TB patients. The fungal-to-bacterial species ratio was significantly decreased, and the bacterial-fungal trans-kingdom interactions have been reduced in TB patients. A set model including Bacteroides, Blautia, Eubacterium_hallii_group, Apiotrichum, Penicillium, and Saccharomyces may provide a better TB diagnostics option than using single bacterial or fungi sets. Also, gut microbial dysbiosis has a strong correlation with the alteration of IL-17 and IFN-γ.

CONCLUSIONS

Our results demonstrate that TB patients exhibit the gut bacterial and fungal dysbiosis. In the clinics, some gut microbes may be considered as potential biomarkers for auxiliary TB diagnosis.

[Impact of hyperoxia on the phenotype of pulmonary artery smooth muscle cells]

Objective: To investigate the influence of varied oxygen (O2) concentration environments on the phenotypic transformation of pulmonary artery smooth muscle cells (PASMC) and the mechanism of pulmonary hypertension. Methods: Primary rat PASMC were isolated and cultured through the process of enzymatic digestion. Following identification, the stable passaged PASMC were subjected to a 6-hour incubation in sealed containers with normal O2 content (group C) and relative O2 content comprising 55% (group H55), 75% (group H75), and 95% (group H95). mRNA and protein expression of α-Actin (α-SMA), smooth muscle 22α (SM22α), osteopontin (OPN), and matrix metalloproteinase-2 (MMP-2) were measured using real-time quantitative PCR and western blot analysis. Results: The H55 group displayed no significant difference from the C group in terms of mRNA and relative protein expression levels for α-SMA, SM22α, OPN, and MMP-2 (all P>0.05). On the other hand, groups H75 and H95 exhibited a reduction in mRNA and relative protein expression of α-SMA and SM22α, along with an increase in mRNA and relative protein expression of OPN and MMP-2 when compared with both the C and H55 groups (all P<0.05). The H95 group showed a higher relative mRNA expression of MMP-2 as compared to the H75 group (P<0.05). Conclusions: Oxygen concentration environments of 75% or higher can serve as the foundation for the pathogenesis of pulmonary hypertension, essentially by inducing a phenotypic transformation in PASMC towards adopting a robust secretory function. This induction is contingent upon the concentration of oxygen present.

Membrane-Based Preparation Process and Antioxidant and Anti-AGEs Activities of a Novel Propolis Ultrafiltrate

Propolis is one functional supplement with hundreds of years of usage. However, it's rarely consumed directly for its resinous property. Herein, a pre-treated process which can remove the impurity while preserve its bioactivities is needed to maximise its therapeutic opportunities. In the present study, a membrane-based ultrafiltration process was developed on a KM1812-NF experimental instrument. Using Brazilian green propolis as testing material, all experimental steps and parameters were sequentially optimized. In addition, a mathematical model was developed to fit the process. As a result, the optimum solvent was 60 % ethanol adjusted to pH 8-9, while the optimum MWCO (molecular weight cut-off) value of membrane was 30 KDa. The membrane filtration dynamic model fitted with the function y=(ax+b)/(1+cx+dx2 ). The resulting propolis ultrafiltrate from Brazilian green propolis, termed P30K, contains the similar profile of flavonoids and phenolic acids as raw propolis. Meanwhile, the ORAC (oxygen radical absorbance capacity) value of P30K is 11429.45±1557.58 μM TE/g and the IC50 value of inhibition of fluorescent AGEs (advanced glycation end products) formation is 0.064 mg/mL. Our work provides an innovative alternative process for extraction of active compounds from propolis and reveals P30K as an efficient therapeutic antioxidant.

Dual Proton/Silver-Catalyzed Serial (5 + 2)-Cycloaddition and Nazarov Cyclization of (E)-2-Arylidene-3-hydroxyindanones with Conjugated Eneynes: Synthesis of Indanone-Fused Benzo[cd]azulenes

A one-pot step-economic tandem process involving (5 + 2)-cycloaddition and Nazarov cyclization reactions has been reported for the facile synthesis of indanone-fused benzo[cd]azulenes from (E)-2-arylidene-3-hydroxyindanones and conjugated eneynes. This highly regio- and stereoselective bisannulation reaction is enabled by dual silver and Brønsted acid catalysis and opens up a new avenue for the construction of important bicyclo[5.3.0]decane skeletons.

[Correlation between dyslipidemia and the risk of papillary thyroid carcinoma]

Objective: To investigate the correlation between dyslipidemia and the risk of papillary thyroid carcinoma (PTC). Methods: A case-control study was conducted. PTC patients diagnosed by pathology in Tianjin Medical University Cancer Institute and Hospital from April 2014 to August 2019 were enrolled as the experimental group, and healthy controls in the physical examination center at the same time were also enrolled as the control group. The demographic data and blood lipid parameters of the subjects were collected. Multivariate logistic analyses were used to assess the correlation between dyslipidemia and the risk of PTC. Results: A total of 2 000 cases of PTC were enrolled, with a mean age of (42±12) years, including 1 419 females (71.0%) and 581 males (29.0%). There were 4 524 cases in the control group, with a mean age of (42±9) years, including 3 311 females (73.2%) and 1 213 males (26.8%). There was no statistically difference in age and gender between the two groups (both P>0.05). Compared with the control group, triglyceride (TG) [(1.7±1.1) vs (1.4±1.0) mmol/L, P<0.001] and low-density lipoprotein (LDL) [(2.9±0.8) vs (2.8±0.7) mmol/L, P=0.015] increased in peripheral blood of PTC patients, while high-density lipoprotein (HDL) [(1.3±0.4) vs (1.4±0.3) mmol/L, P<0.001] decreased, but the difference was not statistically significant in total cholesterol (TC) [(4.9±1.0) vs (4.9±0.8) mmol/L, P=0.172]. After adjusting for age and gender, increase of TC (OR=1.20, 95%CI: 1.06-1.34, P=0.003), TG (OR=1.73, 95%CI: 1.55-1.94, P<0.001), LDL (OR=1.21, 95%CI: 1.08-1.36, P=0.001), LDL/HDL (OR=1.77, 95%CI: 1.56-2.02, P<0.001) and decrease of HDL (OR=3.15, 95%CI: 2.78-3.58, P<0.001) were the related factors of PTC. Conclusions: Compared with the control group, patients with PTC have higher level of TG and LDL and lower level of HDL. Dyslipidemia is an important factor related to the risk of PTC.

[Effects of electroacupuncture at "Zhongliao" and "Xialiao" on serotonin signaling system and short-chain fatty acids in slow transit constipation rats]

OBJECTIVE

To observe the effect of electroacupuncture (EA) at "Zhongliao" (BL33) and "Xialiao" (BL34) on the 5-hydroxytryptamine (5-HT) signaling system in colon tissue and short-chain fatty acids in feces of rats with slow transit constipation (STC), so as to explore the underlying mechanisms of EA in the treatment of STC.

METHODS

A total of 32 SD rats were randomly divided into normal, model, drug control and EA groups, with 8 rats in each group. The STC model was established by intragastric administration of loperamide for 14 days. The EA stimulation (2 Hz/15 Hz) was performed at bilateral BL33 and BL34 for 30 min, once a day for 14 days. The first black stool de-fecation time and fecal water content were detected after treatment. The expressions of 5-hydroxytryptamine 4 receptor (5-HT4R), tryptophan hydroxylase 1 (TPH1) and 5-HT transporter (SERT) in colon tissues were detected by Western blot. The contents of substance P (SP) and vasoactive intestinal peptide (VIP) in serum were detected by ELISA. The contents of 5-HT in colon tissue and short chain fatty acid (SCFA) in feces were detected by mass spectrometry.

RESULTS

Compared with the normal group, the fecal water content, the expressions of 5-HT, 5-HT4R, TPH1 and SERT in colon tissue, the content of serum SP were significantly decreased (P<0.05), the first black stool de-fecation time, and the content of serum VIP was significantly increased (P<0.05), the contents of SCFA in feces were significantly decreased except isobutyric acid (P<0.05) in the model group. Compared with the model group, the fecal water content, the expressions of 5-HT, 5-HT4R, TPH1 and SERT in colon tissues, the contents of acetic acid and butyrate in feces were significantly increased (P<0.05) in the EA and drug control groups, the first black stool defecation time was decreased (P<0.05) in the EA and drug control groups, and the content of serum SP was increased and the content of serum VIP was decreased (P<0.05) in the EA group. Compared with the drug control group, the content of serum VIP was significantly decreased (P<0.05), and the expressions of TPH1 and SERT in colon tissue were significantly increased (P<0.05) in the EA group.

CONCLUSION

EA at BL33 and BL34 can promote intestinal motility by intervening multiple links of 5-HT signaling system in treating STC.

[Correlations of serum TgAb and TPOAb and clinicopathological features of PTC in children and adolescents]

Objective: To analyze the correlations between serum thyroglobulin antibody (TgAb) and thyroid peroxidase antibody (TPOAb) and clinicopathological features in children and adolescents with papillary thyroid carcinoma (PTC). Methods: A retrospective analysis was conduced on the clinicopathological data of children and adolescents (age≤21 years old) with PTC admitted to Tianjin Medical University Cancer Hospital from 2011 to 2019, and then, we used χ² test or Fisher's exact probability test to compare the differences in clinicopathological characteristics between groups with different TgAb and TPOAb status and multivariate logistic regression model analysis to evaluate independent predictors of cervical lymph node metastasis. Results: A total of 304 patients, including 89 males and 215 females, aged 5-21 years (median age 19 years), were enrolled in this study. The comparison between groups with different TgAb and TPOAb status showed that there were significant differences in gender, preoperative thyroglobulin (Tg) level, primary tumor location, number of primary tumors and maximum tumor diameter (all P<0.05), which suggested that TgAb⁺group (n=81) and TPOAb⁺group (n=84) had relatively better primary tumor characteristics. Patitents with TgAb⁺and TPOAb⁺were more common in females and their preoperative Tg level was mostly within the normal range, and there were significant differences in primary tumor location, number of primary tumors and maximum tumor diameter between TgAb⁺and TgAb^-(223 cases) groups (all P<0.05). There was significant difference in the maximum tumor diameter between TPOAb⁺and TPOAb^-(220 cases) groups (P<0.05). Analysis of risk factors for cervical lymph node metastasis showed that independent risk factors for central lymph node metastasis were maximum tumor diameter>2 cm (OR=2.84, 95%CI: 1.59-5.07, P<0.001) and extra-thyroid extension (OR=0.32, 95%CI: 0.17-0.60, P<0.001), and independent risk factors for lateral neck lymph node metastasis included age≤14 years old (OR=0.34, 95%CI: 0.18-0.67, P=0.002), preoperative Tg⁺(OR=2.16, 95%CI: 1.10-4.24, P=0.026) and maximum tumor diameter>2 cm (OR=3.99, 95%CI: 2.33-6.82, P<0.001). Conclusion: It is recommended to test routinely serum TgAb and TPOAb before surgery in children and adolescents with PTC. Preoperative Tg⁺, age≤14 years, maximum tumor diameter>2 cm, and extra-thyroid extension are risk factors for cervical lymph node metastasis.

Meta-analysis on the epidemiology of gastroesophageal reflux disease in China

BACKGROUND

No large-scale epidemiological survey on the prevalence of gastroesophageal reflux disease (GERD) in China has been conducted. China has a large population and a complex geographical environment. It is important to understand the prevalence and spatial distribution of GERD in China.

AIM

To explore the prevalence and the spatial, temporal, and population distributions of GERD in the natural Chinese population.

METHODS

We searched Chinese and English databases for literature on the prevalence of GERD in the natural Chinese population. The prevalence of GERD was pooled using a random-effects meta-analysis model. Subgroup analysis was performed according to time, region, and population. We used ArcGIS software to draw statistical maps and trend analysis charts. Spatial autocorrelation analysis was carried out using Geoda software. Spearman correlation analysis was used to assess the spatial distribution relationship between GERD and upper digestive tract tumours.

RESULTS

Altogether, 70 studies involving 276014 individuals from 24 provinces of China were included. The overall pooled prevalence of GERD was 8.7% (95%CI: 7.5%-9.9%) in mainland China. Over the past two decades, the prevalence of GERD in China has increased from 6.0% to 10.6%. GERD was more common in people aged 40-60, with body mass index ≥ 24, and of Uygur ethnicity. The prevalence was higher in the west and east than in the centre, and there may be a local spatial autocorrelation between the Qinghai-Tibet Plateau and the southeast. GERD was correlated with gastric (r = 0.421, P = 0.041) and oesophageal tumours (r = 0.511, P = 0.011) in spatial distribution.

CONCLUSION

GERD is becoming common in China. The prevalence differs by region and population. The development of appropriate strategies for the prevention and treatment of GERD is needed.

TERRA and RAD51AP1 promote alternative lengthening of telomeres through an R- to D-loop switch

Alternative lengthening of telomeres (ALT), a telomerase-independent process maintaining telomeres, is mediated by break-induced replication (BIR). RAD52 promotes ALT by facilitating D-loop formation, but ALT also occurs through a RAD52-independent BIR pathway. Here, we show that the telomere non-coding RNA TERRA forms dynamic telomeric R-loops and contributes to ALT activity in RAD52 knockout cells. TERRA forms R-loops in vitro and at telomeres in a RAD51AP1-dependent manner. The formation of R-loops by TERRA increases G-quadruplexes (G4s) at telomeres. G4 stabilization enhances ALT even when TERRA is depleted, suggesting that G4s act downstream of R-loops to promote BIR. In vitro, the telomeric R-loops assembled by TERRA and RAD51AP1 generate G4s, which persist after R-loop resolution and allow formation of telomeric D-loops without RAD52. Thus, the dynamic telomeric R-loops formed by TERRA and RAD51AP1 enable the RAD52-independent ALT pathway, and G4s orchestrate an R- to D-loop switch at telomeres to stimulate BIR.

Protocol to stimulate and delineate alternative lengthening of telomeres in human U2OS cells

Alternative lengthening of telomeres (ALT) is a telomerase-independent but recombination-dependent pathway that maintains telomeres. Here, we describe a protocol to stimulate the formation of ALT-associated PML bodies (APBs) and ALT activity by tethering PML-IV to telomeres in human U2OS cells. Through immunofluorescence, in situ hybridization, and microscopy, we analyze dynamics of telomere clustering, visualize recruitment of DNA repair proteins to APBs, and measure telomere DNA synthesis during ALT. This protocol provides a unique approach to delineate the ALT pathway.

For complete details on the use and execution of this protocol, please refer to Zhang et al. (2021).

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An ABA-inducible system to tether PML-IV to telomeres and promote APB formation

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Visualization of proteins and DNA synthesis in APBs by immunofluorescence

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Detection of telomeres by fluorescence in situ hybridization

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Quantification of proteins and DNA synthesis at telomeres in APBs

Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

[Genetic variation of sequences of partial mitochondrial nicotinamide adenine dinucleotide dehydrogenase subunit 1 (pnad1) and pnad5 genes of Toxascaris leonina isolates from foxes and dogs in Jiuquan City of Gansu Province]

OBJECTIVE

To investigate the genetic variations of Toxascaris leonina isolates from different hosts in Jiuquan City, Gansu Province.

METHODS

The mitochondrial sequences of partial mitochondrial nicotinamide adenine dinucleotide dehydrogenase subunit 1 (pnad1) and pnad5 of eleven T. leonina isolates from domestic dogs, foxes and pet dogs in Jiuquan City, Gansu Province, were amplified using PCR, and the amplification product was sequenced. The genetic variations of pnad1 and pnad5 genes in T. leonina isolates were analyzed.

RESULTS

The sequences of T. leonina pnad1 and pnad5 genes measured 530 bp and 550 bp in size, respectively. The nucleotide sequence homology was 99.4% to 100.0% for T. leonina pnad1 gene and 99.5% to 99.8% for T. leonina pnad5 gene, and the sequences of T. leonina pnad1 and pnad5 genes shared 99.2% to 99.9% and 99.1% to 99.9% with corresponding sequences of known T. leonina isolates. In addition, there were 19 and 24 polymorphic sites detected in the sequences of T. leonina pnad1 and pnad5 genes, with 10 and 9 haplotypes, haplotype diversity of 0.982 and 0.964 and nucleotide diversity of 0.039 4 and 0.034 2, respectively. Phylogenetic analysis based on pnad1 and pnad5 gene sequences showed that the eleven T. leonina isolates and known T. leonina isolates were clustered into the same branch with a random distribution, which were close to the branch where Toxocara canis was clustered, and far from the branch where other Ascaris species were clustered.

CONCLUSIONS

There is a minor genetic variation in pnad1 and pnad5 genes of T. leonina isolates from different hosts in Jiuquan City, Gansu Province, and the pnad1 gene is more suitable as a molecular marker than pnad5 gene for analysis of genetic variations in T. leonina.

Effect of cooking methods on the edible, nutritive qualities and volatile flavor compounds of rabbit meat

BACKGROUND

Rabbit meat is a good edible meat source with high nutritional values. Cooking has a significant impact on the edible properties, nutritional qualities and flavor characteristics of meat. Studying the effect of cooking methods on rabbit meat qualities could encourage more understanding and acceptance of rabbit meat by consumers, and could also provide some reference for rabbit meat processing. Therefore, the effects of boiling, sous-vide cooking, steaming, microwaving, roasting, frying and pressure cooking on the edible, nutritive and volatile qualities of rabbit meat were investigated.

RESULTS

The sous-vide cooked rabbit meat sample showed higher moisture content, water-holding capacity and lower cooking losses than other samples, but the results of roasted rabbit meat sample were the opposite, and scanning electron microscopy observations also verified the results. There was no significant difference in 2-thiobarbituric acid reactive substance (TBARS) value in the cooked samples except for roasting. Microwaving, roasting and frying exhibited stronger antioxidant activity than the other cooked samples after in vitro digestion. A total of 38 volatiles were identified in the cooked meat samples, and the samples were well divided into four groups by principal component analysis, and 13 volatiles were considered discriminatory variables for the cooked rabbit meat.

CONCLUSION

The physicochemical characteristics of cooked meat differed significantly between the processing methods. Roasted meat showed lower TBARS value and stronger antioxidant activity after simulated digestion compared to the other meats. However, pressure cooked meat detected the most volatile components while roasting the least. © 2022 Society of Chemical Industry.

[Analysis of the application of radiotherapy facility construction project evaluation standard in health management institutions]

Objective: To investigate the application of GBZ/T 220.2-2009 "The Specification of Radiological Protection Assessment for Occupational Hazard in Construction Project-Part 2: Radiotherapy Facility" in health management institutions, and to understand the scientificity, practicability and problems existing in the implementation of the standard. Methods: The method of multistage stratified sampling and questionnaire survey were used to collect the standard application status among 96 radiological health managers who had participated in the evaluation of radiotherapy facility construction projects in 6 provinces and cities from November 2020 to April 2021. A descriptive statistical analysis method was used to analyze the basic information of the survey object, the knowledge of the standard, the publicity and implementation of the standard. Results: The radiological health management personnel mainly came from health supervision agencies (62.5%, 60/96) , and 86.5% (83/96) were engaged in the pre-evaluation of radiotherapy device construction project and the approval and supervision of control effect evaluation. The awareness rate and training rate of radiological health managers on GBZ/T 220.2-2009 were 88.5% (85/96) and 31.3% (30/96) , respectively. 89.6% (86/96) managers thought it could meet the needs of radiotherapy facility construction project approval or supervision. 49.0% (47/96) of managers believed that the standard needed to be revised. Conclusion: The content of GBZ/T 220.2-2009 is basically scientific and reasonable, but the publicity, implementation and training of radiological health administrator still need to be strengthened. It is suggested to revise some clauses in the standard that do not meet the requirements.

[Application of hybrid surgery in the clipping of large complex paraclinoid aneurysms]

Nine patients with large complex paraclinoid aneurysms were treated by hybrid surgery in the Second Affiliated Hospital of Zhejiang University between January 2016 and July 2021. Intraoperative angiography was conducted for real-time evaluation of the aneurysm and its clipping efficacy. A total of 8 aneurysms were clipped under temporary proximal control with balloon occlusion. Suction decompression was simultaneously applied in 2 of these cases. After surgery, 2 patients developed symptomatic cerebral infarction, 3 patients developed transient oculomotor nerve palsy, but no patients had vision deterioration. Postoperative follow-up showed that small neck residue occurred in 1 case, but with the rest of aneurysms were completely occluded without parent artery stenosis. Hybrid surgery was proved to be advantageous in real-time assessment of aneurysm morphology and clipping efficacy. Combination of temporary proximal balloon occlusion and suction decompression technique can help in reducing the difficulty of aneurysm exposure and remodeling, thereby improving the outcome and decreasing the complications.

[Study of three kinds of primary immunization schedules with poliovirus vaccine]

Objective: To compare the immunogenicity of three kinds immunization programs with poliovirus vaccine. Methods: Healthy infants aged 2 months or over were selected and divided into three groups by complete randomization method. Basic immunization with Sabin inactivated poliovirus vaccine(sIPV) and bivalent oral poliovirus vaccine(bOPV) were completed. Three kinds of basic immunization procedures were 1sIPV+2bOPV,2sIPV+1bOPV and 3sIPV, respectively.Two qualified serums that before basic immunization and 28-42 days later were collected, and measured the poliovirus neutralizing antibody with microcell neutralization method. To compare the difference by analysis of variance, rank test and χ² test. Results: After the basic immunization, 205 subjects of the positive conversion rate of poliovirus neutralizing antibodies of types Ⅰ, Ⅱ and Ⅲwere all higher than 97.00%, and the positive rates were all higher than 98.00%, the geometric mean titer (GMT) of neutralizing antibody was significantly higher than that before basic immunization in three groups.There were significant differences in the positive rate and GMT before and after basic immunization of typeⅠ, Ⅱand Ⅲ in the three (P<0.05). The highest GMT in three groups after basic immunization were all typeⅠ, followed by type Ⅲ, and the lowest in type Ⅱ. The GMT of type Ⅱin 2sIPV+1bOPV and 3sIPV groups were both higher than that in sIPV+2bOPV group. Conclution: After three kinds of basic immunization, the poliovirus neutralizing antibodies of serum were all at high levels in three groups, which could form an effective immune barrier against poliovirus. The immunogenicity of three kinds of basic immunization programs were all well, but there were certain differences of neutralizing antibodies among three kinds basic immunization programs. The immunogenicity in 2sIPV+1bOPV and 3sIPV groups against typeⅡpoliovirus were better than that in 1sIPV+2bOPV group.

Beneficial effect of melatonin administration on the function of frozen-thawed rat testicular grafts

BACKGROUND

Spermatogonia in testis is sensitive to the cytotoxicity of chemotherapy agents. Cryopreservation of testicular tissue may offer fertility restoration in young male cancer survivors.

OBJECTIVE

To investigate the effect of melatonin on the survival of testicular grafts following cryopreservation and transplantation.

MATERIALS AND METHODS

Wister rats were randomly allocated into three groups: control group; saline group (cryopreservation + autograft + saline); and melatonin group (cryopreservation + autograft + melatonin). Malondialdehyde (MDA) content, glutathione peroxidase (GPx) activity and superoxide dismutase (SOD) activity were assessed on day 7 after autograft transplantation. At day 30, graft recovery, spermatogonia per round tubule, and serum testosterone concentration in grafts were measured.

RESULTS

Melatonin significantly diminished MDA content, enhanced GPx and SOD activities. Furthermore, the recovery rate, number of spermatogonia per round tubule, and serum testosterone concentration in melatonin group was markedly higher than the saline group.

CONCLUSION

Melatonin administration at 20 mg/kg is effective in improving the function of frozen and thawed rat testicular graft. The protective role of melatonin can be attributed partly to the enhanced ROS scavenging and antioxidant enzyme activities. doi.org/10.54680/fr22310110612.

Spatial-temporal Distribution and Influencing Factors of Helicobacter pylori Infection in Chinese Mainland, 2001-2020: A Systematic Review and Meta-Analysis

BACKGROUND

The spatial-temporal distribution of Helicobacter pylori infection in China is poorly understood. We aimed to study the spatial-temporal distribution of H. pylori infection in Chinese mainland and to explore its influencing factors.

MATERIALS AND METHODS

We searched the relevant literature from 2001 to 2021 and applied meta-analysis to obtain the pooled prevalence estimates of all studies and subgroups. Then, we used the pooled prevalence as the dependent variable for the following analysis, including time series analysis, statistical mapping, spatial autocorrelation analysis, and influencing factor analysis based on generalized additive model and panel data model.

RESULTS

A total of 726 articles and 3,407,392 people were included. The pooled prevalence was 43.7% (95% confidence interval: 42.7%-44.8%). The prevalence decreased in the past 20 years, with high in the eastern and western regions and low in the central region. Qinghai Tibet Plateau and Guizhou Plateau were the high incidence areas of this disease. The intake of vegetable oil, aquatic products, meat, milk, per capita gross domestic product, and annual average humidity were significantly correlated with H. pylori.

CONCLUSIONS

The prevalence of H. pylori is decreasing in Chinese mainland, but still high in underdeveloped areas. Appropriate strategies for the prevention need greater attention.

Ding's herbal enema treats dextran sulfate sodium-induced colitis in mice by regulating the gut microbiota and maintaining the Treg/Th17 cell balance

Ding's herbal enema (DHEP) is a traditional Chinese medicinal therapy that has been used to treat ulcerative colitis (UC) in China. The present study determined the molecular mechanism of the effect of DHEP in UC treatment. C57BL/6J mice were treated with 3.5% (w/v) dextran sulfate sodium (DSS) for 7 days to establish an animal model of colitis. The mice were divided into five groups (n=5): Control, vehicle, DHEP, mesalazine and β-sitosterol. After oral administration for 7 days, the body weight, disease activity index, histopathology and inflammatory factors were analyzed. The fractions of CD4+Foxp3+ regulatory T (Treg) cells and CD4+IL-17A+ T helper (Th) cells were determined by flow cytometry. Gut microbiota composition was analyzed by next-generation sequencing. The results revealed that DHEP and β-sitosterol could significantly alleviate the symptoms of DSS-induced UC. Furthermore, the levels of IL-6, cyclooxygenase-2, TNF-α and p65 were reduced after administration of DHEP. Additionally, the data indicated that DHEP could increase the abundance of seven operational taxonomic units (OTUs) and decrease the abundance of 12 OTUs in the gut microbiota. The content of short-chain fatty acids in the colon remodeled the balance of Treg/Th17 cells in DSS-induced UC in mice. The present study preliminarily defined the mechanism of action of DHEP in UC that may be associated with the regulation of the gut microbiota composition, and maintenance of the balance between Treg and Th17 cells. Furthermore, β-sitosterol exhibited the same effects with DHEP and it could be a possible substitute for DHEP in UC treatment.

[Intestinal flora polymorphisms with different lesional stages in an animal model of MAFLD]

Objective: To study the intestinal flora specific differences with different lesional stages of metabolic (disorder) associated fatty liver disease (MAFLD), namely simple steatosis and steatohepatitis, so as to provide a new direction for MAFLD-related intestinal flora transplantation and targeted therapy. Methods: Mice were fed with normal diet, methionine-choline deficient diet (MCD) and a high-fat high-fructose diet (HFHF) for 12 weeks to construct simple steatosis and steatohepatitis models. HE and Sirius scarlet staining was performed to observe the liver pathological changes. The qPCR method was used to evaluate inflammation and liver fibrosis factors. A fully automatic biochemical analyzer was used to detect changes in liver transaminase and blood lipids. 16S rRNA sequencing method was used to observe the intestinal flora differences in the feces of each group of mice. The comparison of means between two groups was performed by t-test, and the comparison of means between multiple groups was performed by one-way analysis of variance. Kruskal-Wallis rank sum test was used for non-normally distributed data. Results: NAFLD scores were determined with pathological sections (HE and Sirius scarlet staining) of mice liver, which showed that the inflammation and liver fibrosis scores of the MCD and HFHF groups were 2.12 ± 0.18 and 1.06 ± 0.24, and 2.22 ± 0.16 and 0.46 ± 0.10, respectively. The degree of liver inflammation and fibrosis was significantly higher in the MCD than the HFHF group (P < 0.001 and P < 0.01). Lipid deposition was higher in the HFHF than the MCD group (P < 0.001), and the scores were 2.36 ± 0.17 and 1.60 ± 0.24 respectively. Simultaneously, the inflammatory [tumor necrosis factor-A (TNF-a), chemokine factor-2 (CXCL-2)] and hepatic fibrosis indicators [vascular smooth muscle actin alpha (a-SMA) and connective tissue growth factor (CTGF)] had confirmed the above-mentioned results at the transcription level. Moreover, the intestinal flora diversity was reduced (P < 0.05) in the MCD group than the HFHF group, and the Simpson and Shannon index were 0.31 ± 0.10 and 0.42 ± 0.05, and 2.03 ± 0.33 and 1.70 ± 0.28, respectively, and the differences were significant between different intestinal flora groups. The levels of Desulfovibrio, Odoribacter, and Roseburia flora were significantly increased in the HFHF than the MCD group, and the levels of Faecalibaculum, Parasutterella, Alipis, Butyricimonas_virosa, Turicibacter_sp, and Romboutsia_ilealis were significantly increased in the MCD than the HFHF group, and the difference was statistically significant (P < 0.05). Conclusion: There are significant differences in intestinal flora diversity between simple steatosis and steatohepatitis models. Therefore, clarifying the difference between the two may provide a new direction for the stage manner treatment of MAFLD.

NR4A1 regulates expression of immediate early genes, suppressing replication stress in cancer

Deregulation of oncogenic signals in cancer triggers replication stress. Immediate early genes (IEGs) are rapidly and transiently expressed following stressful signals, contributing to an integrated response. Here, we find that the orphan nuclear receptor NR4A1 localizes across the gene body and 3' UTR of IEGs, where it inhibits transcriptional elongation by RNA Pol II, generating R-loops and accessible chromatin domains. Acute replication stress causes immediate dissociation of NR4A1 and a burst of transcriptionally poised IEG expression. Ectopic expression of NR4A1 enhances tumorigenesis by breast cancer cells, while its deletion leads to massive chromosomal instability and proliferative failure, driven by deregulated expression of its IEG target, FOS. Approximately half of breast and other primary cancers exhibit accessible chromatin domains at IEG gene bodies, consistent with this stress-regulatory pathway. Cancers that have retained this mechanism in adapting to oncogenic replication stress may be dependent on NR4A1 for their proliferation.

[Research progress on the human health risks assessment of radionuclides in water environment]

The quality of the water environment is one of the most important factors that can directly affect the health of human beings and other non-human species. The levels of the radionuclides in water environment are the key indicator while assessing the quality of water environment. Recently, with the development of the nuclear energy in China, the public people have paid a focus attention on the levels and the health risks of the radionuclides. This paper introduced the sources, the health effects, the health risk assessment methods and the current status of the health risk assessment study about the radionuclides, in order to provide basis for the health risk assessment of radionuclides in water environment and the protection of human health.

Toxicity of CuS/CdS semiconductor nanocomposites to liver cells and mice liver

Semiconductor nanomaterials not only bring great convenience to peoples lives but also become a potential hazard to human health. The purpose of this study was to evaluate the toxicity of CuS/CdS nanocomposites in hepatocytes and mice liver. The CuS/CdS semiconductor nanocomposites were synthesized by a biomimetic synthesis - ion exchange strategy. Nanosize was confirmed by high-resolution transmission electron microscopy and dynamic light scattering. The composition and physical properties were measured by powder X-ray diffraction, Fourier transform infrared spectra, atomic absorption spectroscopy, thermogravimetry-differential scanning calorimetry and zeta potential analysis. The results revealed that CuS/CdS nanocomposites had 8.7 nm diameter and negative potential. Ion exchange time could adjust the ratio of CuS and CdS in nanocomposites. The toxicological study revealed that CuS/CdS nanocomposites could be internalized into liver cells, inhibited endogenous defense system (e.g. GSH and SOD), induced the accumulation of oxidation products (e.g. ROS, GSSG and MDA), and caused hepatocyte apoptosis. The in vivo experiments in Balb/c mice showed that the experimental dose (4 mg/kg) didn't cause observable changes in mice behavior, physical activity and pathological characteristics, but the continuous accumulation of Cd²⁺ in the liver and kidney might be responsible for its long-term toxicity.

[Indications, selection, and effect of flap application in repairing scar carcinoma in the lower leg and ankle]

Objective: To explore the indications, selection, and effect of flap application in repairing scar carcinoma in the lower leg and ankle. Methods: A retrospective cohort study was conducted. From June 2008 to December 2018, six male patients with scar carcinoma in the lower leg and ankle were treated in Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, aged 48-64 years, with the area of lesion ranging from 3 cm×2 cm to 15 cm×6 cm. After extended resection, the defect area ranged from 8 cm×5 cm to 22 cm×9 cm, with tissue of tendon or bone exposed. Free anterolateral thigh perforator flap, latissimus dorsi myocutaneous flap, or pedicled sural neurovascular flap was selected to repair the wound according to the location of wound in the lower extremity, selection of operation position, the location of the anastomotic vessels in the recipient area, and whether there was good skin and soft tissue available in the lower leg. The size of flap was 11 cm×8 cm-26 cm×10 cm. The donor site of free flap or myocutaneous flap was closed directly by suturing in 5 cases, and the donor site of pedicled flap was repaired with full-thickness skin graft in 1 case. The blood supply and survival of flap, quality of skin graft survival, and complication were observed postoperatively. During the follow-up period, the recurrence and metastasis of scar carcinoma, and the appearance and function of donor and recipient sites were observed. Results: All the patients completed the operation successfully, all the transplanted flaps survived with good blood supply, and the skin graft in one donor site survived well. The wounds in the donor and recipient sites of all the patients healed well without infection, effusion, or dehiscence, etc. All the patients were followed up for 1-5 years. No local recurrence or distant metastasis of scar carcinoma was found. The quality of the transplanted flaps was good. The shape of the recipient area was quite good, and the function of the affected limb was fine. The appearance of the donor area was good without dysfunction. Conclusions: Flap transplantation is suitable for the patients with tendon and bone exposure after the excision of scar carcinoma in the lower leg and ankle. The flap can be selected according to the location of scar carcinoma, operation position, the location of anastomotic vessels in the recipient area, and whether there is good skin and soft tissue available in the lower leg. The free anterolateral thigh perforator flap or latissimus dorsi myocutaneous flap is an ideal choice for repair, which can be obtained in a large area, and the donor site can be directly sutured without affecting the function.

RNA transcripts stimulate homologous recombination by forming DR-loops

Homologous recombination (HR) repairs DNA double-strand breaks (DSBs) in the S and G2 phases of the cell cycle^1-3. Several HR proteins are preferentially recruited to DSBs at transcriptionally active loci^4-10, but how transcription promotes HR is poorly understood. Here we develop an assay to assess the effect of local transcription on HR. Using this assay, we find that transcription stimulates HR to a substantial extent. Tethering RNA transcripts to the vicinity of DSBs recapitulates the effects of local transcription, which suggests that transcription enhances HR through RNA transcripts. Tethered RNA transcripts stimulate HR in a sequence- and orientation-dependent manner, indicating that they function by forming DNA-RNA hybrids. In contrast to most HR proteins, RAD51-associated protein 1 (RAD51AP1) only promotes HR when local transcription is active. RAD51AP1 drives the formation of R-loops in vitro and is required for tethered RNAs to stimulate HR in cells. Notably, RAD51AP1 is necessary for the DSB-induced formation of DNA-RNA hybrids in donor DNA, linking R-loops to D-loops. In vitro, RAD51AP1-generated R-loops enhance the RAD51-mediated formation of D-loops locally and give rise to intermediates that we term 'DR-loops', which contain both DNA-DNA and DNA-RNA hybrids and favour RAD51 function. Thus, at DSBs in transcribed regions, RAD51AP1 promotes the invasion of RNA transcripts into donor DNA, and stimulates HR through the formation of DR-loops.

Coinheritance of OLFM2 and SIX6 variants in a Chinese family with juvenile-onset primary open-angle glaucoma: A case report

BACKGROUND

Juvenile-onset primary open-angle glaucoma (JOAG), characterized by severe elevation of intraocular pressure and optic neuropathy prior to the age of 40, is a rare subtype of primary open-angle glaucoma. Several genetic mutations have been associated with JOAG.

CASE SUMMARY

The proband patient was a young male, diagnosed with primary open-angle glaucoma at the age of 27. The patient and his unaffected parents who have been excluded from classic genetic mutations for primary open-angle glaucoma were included to explore for other possible genetic variants through whole genome sequencing and bioinformatics analysis. In this trio, we found two heterozygous variants inherited from the parents in the proband: c.281G>A, p.Arg94His in OLFM2 and c.177C>G, p.Ile59Met in SIX6. Both genetic mutations are predicted through bioinformatics analysis to replace evolutionary conserved amino acids, therefore rendering a pathogenic effect on proteins. In contrast, very low frequencies for these genetic mutations were recorded in most common control databases.

CONCLUSION

This is the first report on coinherited mutations of OLFM2 and SIX6 in a JOAG family, which shows the complexity of JOAG inheritance. Large-scale clinical screening and molecular functional investigations on these coinherited mutations are imperative to improve our understanding of the development of JOAG.

Damage of Granusola and Stroma Cells Exposed to Mouse Ovarian Tissue Cryopreservation: Potential Mechanism of Ovarian Injury

BACKGROUND

Several obstacles must be overcome before ovarian tissue cryopreservation can be used as a standard procedure.

OBJECTIVE

To carry out a morphologic and functional study of the effect of cryopreservation on mouse follicles and stroma cells.

MATERIALS AND METHODS

Female mice were divided into three groups (control, fresh graft and cryopreserved graft). Ultrastructural features of follicles and stroma cells were evaluated using transmission electron microscopy. After autologous transplantation, micro-vessel densities of grafts were examined.

RESULTS

Vacuoles in granulosa cells and stromal cells are significantly greater than that of oocytes. The microvessel density of fresh grafts is significantly higher than that in frozen-thawed grafts.

CONCLUSION

Granusola and stroma cells, rather than oocytes, are vulnerable to cryoinjury. Injuries to granulosa cells and stromal cells could be the critical part of ovarian damage caused by cryopreservation.

[Cost-effectiveness of primary prophylaxis with PEG-rhG-CSF in early-stage breast cancer patients receiving chemotherapy in China]

Objective: To evaluate the cost effectiveness of primary prophylaxis (PP) with pegylated recombinant human granulocyte colony stimulating factor (PEG-rhG-CSF), PP with recombinant human granulocyte colony stimulating factor (rhG-CSF) and no prophylaxis in women with early-stage breast cancer in China. Methods: Two phase Markov models were constructed for a hypothetical cohort of patients aged 45 with stage Ⅱ breast cancer. The first phase modelled costs and outcomes of 4 cycles docetaxel combined with cyclophosphamide [TC×4, febrile neutropenia (FN) risk>20%] chemotherapy, which assumptions based on literature reviews, including FN rates [base-case (deterministic sensitivity analysis range), 0.29 (0.24-0.35)] and related events [FN case-fatality, 3.4 (2.7-4.1)]. Second phase modelled the long term survival which was link with the relative dose intensity (RDI) [mortality hazard ratio (HR) of RDI < 85% vs ≥85%, 1.45 (1.00-2.32)]. Clinical effectiveness, therapeutic costs, and economic utilities were estimated from peer-reviewed publications and expert opinions in case of unavailability of published evidences. Results: Compared to rhG-CSF PP and no prophylaxis, the cost of PEG-rhG-CSF PP increased to 5 208.19 RMB and 5 222.73 RMB, respectively. The quality-adjusted life-years (QALYs) enhanced to 0.066 and 0.297, respectively. Accordingly, the incremental cost effectiveness ratios (ICERs) are 79 146.3 RMB and 17 558.77 RMB per QALY, which were both below the willingness to pay (WTP) threshold of three times GDP per capita (18, 000 RMB) recommended by the WHO. Sensitivity analysis suggested that the more clinically effective the primary prophylaxis with PEG-rhG-CSF is, the more cost-effective primary prophylaxis with PEG-rhG-CSF will be. And the lower the mortality HR of RDI<85% vs ≥85% is, the more cost-effective primary prophylaxis with PEG-rhG-CSF will be. Conclusion: Although the cost of PP PEG-rhG-CSF is higher, considering the additional benefits, the administrating of PP PEG-rhG-CSF is likely to be a cost-effective alternative to PP rhG-CSF and no prophylaxis in patients with early stage breast cancer whose FN risks are more than 20% in China.

Analysis of Clinical Efficacy of Traditional Chinese Medicine in Recovery Stage of Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

We provide an updated meta-analysis with detailed information on a combination of TCM and routine treatment.

METHODS

Retrieve appropriate articles with no language restrictions on keywords until 8 July 2019 in an electronic database. All trajectories are screened according to certain criteria. The quality of certified research was also evaluated. We made a detailed record of the results of the measurement. Meta-analysis was carried out by using the Revman 5.3 software.

RESULTS

Sixty-seven RCTs were included, and 6594 subjects were analyzed. Compared with routine treatment, the total effective rate (TER) of TCM combined with routine treatment was improved, and the recovery of stroke was also significantly accelerated. Regulation of blood lipids by notably shrinking the contents of TC, TG, and LDL and enhancing the levels of HDL. The levels of serum hs-CRP, WHV, and WLV decreased significantly, indicating that the expression of thrombomodulin was decreased after the comprehensive treatment of traditional Chinese medicines (TCMs). The combination of TCM treatment could enhance the protection of neural function by decreasing the NIHSS scoring while increasing the BI scoring. Paeoniae Radix Rubra, Angeticae Sinensis Radix, etc., can effectively improve the clinical symptoms of stroke convalescent patients and promote the recovery of neurological function. ACU of Baihui, Renzhong, etc., can improve the clinical rehabilitation effect of patients. However, our findings must be handled with care because of the small sample size and low quality of clinic trials cited. Other rigorous and large-scale RCTs are in need to confirm these results.

CONCLUSION

A combination of TCM and routine treatment in the treatment of stroke could improve TER, and it is beneficial to the rehabilitation of patients in the recovery period of apoplexy. These effects can be mediated by a combination of several mechanisms. Nevertheless, due to the limitations of this study, these results should be handled with caution.

Synthetic lethality by targeting the RUVBL1/2-TTT complex in mTORC1-hyperactive cancer cells

Despite considerable efforts, mTOR inhibitors have produced limited success in the clinic. To define the vulnerabilities of mTORC1-addicted cancer cells and to find previously unknown therapeutic targets, we investigated the mechanism of piperlongumine, a small molecule identified in a chemical library screen to specifically target cancer cells with a hyperactive mTORC1 phenotype. Sensitivity to piperlongumine was dependent on its ability to suppress RUVBL1/2-TTT, a complex involved in chromatin remodeling and DNA repair. Cancer cells with high mTORC1 activity are subjected to higher levels of DNA damage stress via c-Myc and displayed an increased dependency on RUVBL1/2 for survival and counteracting genotoxic stress. Examination of clinical cancer tissues also demonstrated that high mTORC1 activity was accompanied by high RUVBL2 expression. Our findings reveal a previously unknown role for RUVBL1/2 in cell survival, where it acts as a functional chaperone to mitigate stress levels induced in the mTORC1-Myc-DNA damage axis.

Comparative review and the recent progress in detection technologies of meat product adulteration

Meat adulteration, mainly for the purpose of economic pursuit, is widespread and leads to serious public health risks, religious violations, and moral loss. Rapid, effective, accurate, and reliable detection technologies are keys to effectively supervising meat adulteration. Considering the importance and rapid advances in meat adulteration detection technologies, a comprehensive review to summarize the recent progress in this area and to suggest directions for future progress is beneficial. In this review, destructive meat adulteration technologies based on DNA, protein, and metabolite analyses and nondestructive technologies based on spectroscopy were comparatively analyzed. The advantages and disadvantages, application situations of these technologies were discussed. In the future, determining suitable indicators or markers is particularly important for destructive methods. To improve sensitivity and save time, new interdisciplinary technologies, such as biochips and biosensors, are promising for application in the future. For nondestructive techniques, convenient and effective chemometric models are crucial, and the development of portable devices based on these technologies for onsite monitoring is a future trend. Moreover, omics technologies, especially proteomics, are important methods in laboratory detection because they enable multispecies detection and unknown target screening by using mass spectrometry databases.

Alternative lengthening of telomeres: from molecular mechanisms to therapeutic outlooks

To escape replicative senescence, cancer cells have to overcome telomere attrition during DNA replication. Most of cancers rely on telomerase to extend and maintain telomeres, but 4-11% of cancers use a homologous recombination-based pathway called alternative lengthening of telomeres (ALT). ALT is prevalent in cancers from the mesenchymal origin and usually associates with poor clinical outcome. Given its critical role in protecting telomeres and genomic integrity in tumor cells, ALT is an Achilles heel of tumors and an attractive target for cancer therapy. Here, we review the recent progress in the mechanistic studies of ALT, and discuss the emerging therapeutic strategies to target ALT-positive cancers.

Alternative Lengthening of Telomeres through Two Distinct Break-Induced Replication Pathways

Alternative lengthening of telomeres (ALT) is a telomerase-independent but recombination-dependent pathway that maintains telomeres. Here, we describe an assay to visualize ALT-mediated telomeric DNA synthesis in ALT-associated PML bodies (APBs) without DNA-damaging agents or replication inhibitors. Using this assay, we find that ALT occurs through two distinct mechanisms. One of the ALT mechanisms requires RAD52, a protein implicated in break-induced DNA replication (BIR). We demonstrate that RAD52 directly promotes telomeric D-loop formation in vitro and is required for maintaining telomeres in ALT-positive cells. Unexpectedly, however, RAD52 is dispensable for C-circle formation, a hallmark of ALT. In RAD52-knockout ALT cells, C-circle formation and RAD52-independent ALT DNA synthesis gradually increase as telomeres are shortened, and these activities are dependent on BLM and BIR proteins POLD3 and POLD4. These results suggest that ALT occurs through a RAD52-dependent and a RAD52-independent BIR pathway, revealing the bifurcated framework and dynamic nature of this process.

An R-loop-initiated CSB-RAD52-POLD3 pathway suppresses ROS-induced telomeric DNA breaks

Reactive oxygen species (ROS) inflict multiple types of lesions in DNA, threatening genomic integrity. How cells respond to ROS-induced DNA damage at telomeres is still largely unknown. Here, we show that ROS-induced DNA damage at telomeres triggers R-loop accumulation in a TERRA- and TRF2-dependent manner. Both ROS-induced single- and double-strand DNA breaks (SSBs and DSBs) contribute to R-loop induction, promoting the localization of CSB and RAD52 to damaged telomeres. RAD52 is recruited to telomeric R-loops through its interactions with both CSB and DNA:RNA hybrids. Both CSB and RAD52 are required for the efficient repair of ROS-induced telomeric DSBs. The function of RAD52 in telomere repair is dependent on its ability to bind and recruit POLD3, a protein critical for break-induced DNA replication (BIR). Thus, ROS-induced telomeric R-loops promote repair of telomeric DSBs through CSB-RAD52-POLD3-mediated BIR, a previously unknown pathway protecting telomeres from ROS. ROS-induced telomeric SSBs may not only give rise to DSBs indirectly, but also promote DSB repair by inducing R-loops, revealing an unexpected interplay between distinct ROS-induced DNA lesions.

Inhibition of mTORC1 Signaling Pathway is a Valid Therapeutic Strategy in Transplantation of Cryopreserved Mouse Ovarian Tissue

BACKGROUND

Blockage of mTOR1 can inhibit the transformation of primordial follicles into growing follicles in the ovaries.

OBJECTIVE

The aim of this study was to investigate the role of mTORC1 inhibition in the cryopreservation and transplantation of mouse ovarian tissues.

MATERIALS AND METHODS

ICR (Institute of Cancer Research) mice were randomly divided into control group (autograft), cryopreservation group (cryopreservation + autograft), and mTORC1 inhibition group (cryopreservation + autograft + mTOR inhibitor). After 30 days of auto-transplantation, the follicle number of graft and kit ligand (KL) immunostaining in grafts were quantified. In addition, serum concentration of anti-Müllerian hormone (AMH) was examined by ELISA.

RESULTS

The graft in mTORC1 inhibition group showed a significantly higher proportion of primordial follicles and a significantly lower proportion of growing follicles compared with cryopreservation group. Furthermore, a significant decrease in expression of KL (a marker gene related to follicular development) was observed in mTORC1 inhibition group in contrast to cryopreservation group. The follicle number of graft and serum AMH concentration in mTORC1 inhibition group were significantly higher than that in cryopreservation group.

CONCLUSION

Inhibition of mTORC1 signaling pathway is a valid therapeutic strategy in transplantation of cryopreserved mouse ovarian tissue via suppression of primordial follicle activation.

THE PI3K/Akt/mTOR Signaling Pathway Plays a Role in Regulating Autophagy in Mouse Oocytes During Vitrification-warming and in vitro Maturation

BACKGROUND

It has been shown that vitrified-warmed oocytes exhibit autophagic activation. However, its regulatory molecular mechanism of autophagy needs to be clarified.

OBJECTIVE

To determine the role of signaling pathway of PI3K/Akt/mTOR in the regulation of autophagy in oocytes during vitrification-warming and IVM.

MATERIALS AND METHODS

Oocytes from mice were vitrified-warmed and IVM. The expressions of LC3-II, Beclin-1, PI3K, Akt, and mTOR protein were determined. Moreover, the ATP level, viability of vitrified-warmed oocytes, and their developmental potential were measured.

RESULTS

At 6 h of incubation of warmed oocytes, the LC3-II and Beclin-1 expressions were markedly up-regulated, whereas PI3K, Akt, and mTOR proteins expressions were significantly down-regulated. In addition, autophagy inhibition significantly decreased ATP level, viability of oocytes, and their developmental potential.

CONCLUSION

Autophagy plays a protective role in the oocytes during vitrification-warming and IVM. The PI3K/Akt/mTOR pathway participated in regulating autophagy activity in oocyte during vitrification-warming and IVM.

ATR Protects the Genome against R Loops through a MUS81-Triggered Feedback Loop

R loops arising during transcription induce genomic instability, but how cells respond to the R loop-associated genomic stress is still poorly understood. Here, we show that cells harboring high levels of R loops rely on the ATR kinase for survival. In response to aberrant R loop accumulation, the ataxia telangiectasia and Rad3-related (ATR)-Chk1 pathway is activated by R loop-induced reversed replication forks. In contrast to the activation of ATR by replication inhibitors, R loop-induced ATR activation requires the MUS81 endonuclease. ATR protects the genome from R loops by suppressing transcription-replication collisions, promoting replication fork recovery, and enforcing a G2/M cell-cycle arrest. Furthermore, ATR prevents excessive cleavage of reversed forks by MUS81, revealing a MUS81-triggered and ATR-mediated feedback loop that fine-tunes MUS81 activity at replication forks. These results suggest that ATR is a key sensor and suppressor of R loop-induced genomic instability, uncovering a signaling circuitry that safeguards the genome against R loops.

[Polysaccharide from Phellinus igniarius alleviates oxidative stress and hepatic fibrosis in Schistosoma japonicum-infected mice]

OBJECTIVE

To evaluate the role of polysaccharide from Phellinus igniarius (PPI) in the improvement of oxidative stress, hepatic granuloma and hepatic fibrosis in Schistosoma japonicum-iniected in mice.

METHODS

The mouse model of schistosomiasis was established by S. japonicum cercariae infection via the abdomen. Balb/c mice were randomly assigned into 5 groups, including the healthy control group (Group A), infection control group (Group B), PPI treatment group (Group C), praziquantel treatment group (Group D) and PPI-praziquantel combination group (Group E), of 10 mice in each group. Each mouse in groups B, C, D and E was infected with (30 ± 2) S. japonicum cercariae. Then, mice in groups D and E were given praziquantel by gavage at a dose of 500 mg/kg for successive two days on day 42 post-infection, while mice in groups C and E were given PPI by gavage at a dose of 400 mg/kg for successive 30 days on day 42 post-infection. Histopathological changes of hepatic tissues were observed using hematoxylin-eosin (HE) staining, and serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hyaluronic acid (HA), laminin (LN) were determined, while the activities of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), glutathione reductase (GSH-R) and glutathione (GSH) were detected in Mouse liver homogenates. The expression of transforming growth factor-beta (TGF-β) and alpha-smooth muscle actin (α-SMA) was quantified in hepatic tissues using immunohistochemistry, and the Nrf2 and Gsta4 gene expression was quantified using quantitative real-time PCR (qPCR) assay.

RESULTS

Untreated mice presented typical pathological changes of schistosomal hepatic disorders, while PPI treatment effectively alleviated hepatic egg granulomas and collagen deposition. S. japonicum infection resulted in aggravation of hepatic lipid peroxidation, induction of oxidative stress, elevated serum MDA level and a reduction in the activity of GSH and antioxidant enzymes activities in mice. As compared to infected but untreated mice, PPI treatment suppressed hepatic lipid peroxidation, increased the GSH activity and restored the activity of antioxidant enzymes. In addition, PPI treatment inhibited the TGF-β signaling pathway and up-regulated the Nrf2 and Gsta4 gene expression.

CONCLUSIONS

PPI plays a critical role in the treatment of schistosomiasis-induced hepatic fibrosis. It may improve oxidative stress damages through up-regulating Nrf2 and Gsta4 gene expression, thereby suppressing the development of hepatic egg granulomas and hepatic fibrosis.

[Current status of occupational stress among medical staff in Shenzhen, China and related influencing factors]

Objective: To investigate the current status of occupational stress in medical staff in Shenzhen, China, and to provide a reference for developing health administrative policy and reducing occupational stress in medical staff. Methods: From January to June, 2018, a cross-sectional survey was performed in 992 medical workers who were selected from 2 municipal hospitals and 2 district hospitals by stratified random sampling. General information was collected, Occupational Stress Inventory-Revised Edition was used to investigate occupational stress, and univariate and multivariate analyses were performed based on a descriptive analysis of related results. Results: For the medical staff in Shenzhen, the scores of Occupational Role Questionnaire, Personal Stress Questionnaire, and Personal Resources Questionnaire were 185.67±17.55, 108.45±15.56, and 122.74±16.56, respectively. Age, degree of education, type of work, job title, professional title, and permanent or temporary job were influencing factors for occupational task (P<0.05) ; age, working years, type of work, and night shift were influencing factors for personal stress response (P<0.05) ; working years, type of work, professional title, and weekly working hours were influencing factors for personal coping resources (P<0.05) . Conclusion: There is a high degree of occupational stress among medical staff in Shenzhen, and it is recommended to improve medical resources in Shenzhen, reduce occupational stress among medical staff, and increase coping resources.

[Feasibility and safety of new "blind" axillary vein puncture technique in pacemaker implantation]

Objective: To explore the feasibility and safety of a newly developed simple and rapid axillary vein puncture technique based on the surface landmarks for pacemaker implantation. Methods: From January to November 2018, we enrolled 110 patients who underwent pacemaker implantation in Beijing Anzhen Hospital. Basic clinical characteristics, such as gender, age, major diagnosis, type of pacemaker, and His-purkinje system pacing, were collected. The success rate of this axillary vein puncture technique, complications, and technical parameters of present puncture method were analyzed. Results: There were 58 (52.7%) male patients in this cohort and the average aged was (70.26±10.45) years old. This "blind" axillary vein puncture method was successful in 105 out of 110 patients (95.5%). The relevant puncture-related parameters included: the distance between points "a and b" was (3.89±0.40) cm, the first angle α was (25.84±5.54)° and the second angle β was (66.18±10.26)°. There were no puncture-related complications, such as hematoma, pneumothorax and hemothorax. Conclusion: The new "blind" axillary vein puncture approach is a simple, effective and safe technique for pacemaker implantation, which is easy to learn and practice and suitable for promotion.

[The epidemiological characteristics of silicosis cases in Tianjin from 2001 to 2015]

Objective: To provide scientific evidence for the prevention and control measures of silicosis by analyzing the epidemiological characteristics of silicosis cases reported in Tianjin city during 2001-2015. Methods: The database of silicosis cases reported in Tianjin from 2001 to 2015 was established and analyzed by SPSS 24.0 software. Results: 2 213 cases of silicosis were reported during 2001~2015 in Tianjin, 2015 of them were new cases, and fewer reports of promoting stage cases and death cases, which were129 and 69 cases. The new cases were increasing by years, mainly stage I silicosis accounting for 99.2%, the years of dust exposure were concentrated from 1970 to 1989, accounting for 69.58%. From 2001 to 2015, the median length of service at the onset of silicosis was 19.30 years, the age of the onset of silicosis is decreasing. The median of onset age in new cases of silicosis was 53.28 years, and increased year by year. There were significant differences in indirect dust working age and diagnostic age in different reporting years. Most cases were distributed in non-mental mineral product industry, and ferrous metal smelting and rolling processing industry. The work types of these cases are various. Conclusion: The increasing incidence of silicosis and the shortening of dust-exposed working years suggest that the form of silicosis hazards is still severe in Tianjin. According to the epidemic characteristics of silicosis, we should strengthen the supervision and management of key industries and special investigation, carry out silicosis census and silicosis screening of dust-removal workers, and take pertinent measures to prevent and control the occurrence of silicosis.

[Analysis on condom use negotiation with sex partners and condom use in female sex workers]

Objective: To know condom use negotiation with clients and regular sex partners and condom use in female sex workers (FSWs), and provide reference for the development of comprehensive HIV/AIDS intervention for FSWs. Methods: The cross sectional survey was conducted in Jianshui county and Mengzi county in Honghe Hani and Yi autonomous prefecture. A total of 476 FSWs aged 16 years and above were recruited from entertainment venues, and the information about their demographic characteristics, condom use negotiation and condom use were collected by using questionnaires. Logistic regression model was used to analyze related factors of condom use after negotiation between FSWs and clients unwilling use condom. Results: A total of 852 FSWs who aged (24.29±8.44) years old participated in the survey. In past month, 499 FSWs had negotiation for condom use with unwilling clients (58.6%, 499/852), after negotiation, 441 FSWs (88.4%, 441/499) had consistent condom use in each sex with the clients. In the past one month, 99 FSWs had negotiation for unwilling use condom with regular sex partners (14.4%, 99/687), after negotiation, 54 FSWs (54.5%, 54/99) had consistent condom use in each sex with regular sex partners. Among the FSWs, 266 (53.3%, 266/499) reported that they could say "It is a mandatory requirement" to persuade clients who were unwilling to use condom. 97(19.4%, 97/499) reported that they could say "There is risk for infection" to persuade clients who were unwilling to use condoms. 115 (23.1%,115/499) reported that they could say "It is a mandatory requirement" and "there is risk for infection" to persuade their unwilling clients to use condoms. 21 (4.2%, 21/499) reported that they used other strategies. 22 (4.4%, 22/499) felt that it was difficult to persuade clients to use condoms. Multivariate logistic regression analysis showed that compared with FSWs who felt difficult in persuading clients to use condoms, FSWs who felt moderate difficulty were more likely to have consistent condom use after negotiation (OR=4.00, 95%CI: 1.55-10.32) and FSWs who felt easy in persuading clients to use condoms were also more likely to have consistent condom use (OR=30.17, 95%CI: 3.22-282.44). Compared with FSWs used other strategies to persuade their clients to use condoms, FSWs who said it was a mandatory requirement were more likely to have consistent condom use after negotiation (OR=4.44, 95%CI: 1.41-14.01) and FSWs who said it was a mandatory requirement and there was risk for infection were also more likely to have consistent condom use (OR=5.52, 95%CI: 1.55-19.73). Conclusions: Negotiation for condom use increased the rate of condom use in FSWs in sex with clients who were unwilling to use condom. The negotiation strategy of "It is a mandatory requirement" would promote condom use in FSWs in sex with clients who were unwilling to use condom. Besides, the negotiation strategy of saying "there is risk for infection" had additional effects.

[Circulating MicroRNA in diagnosis of nasopharyngeal carcinoma:a Meta-analysis]

Objective:To evaluate the diagnostic value of circulating microRNAs in nasopharyngeal carcinoma by Meta-analysis. Method:A number of databases in Chinese and English were searched, and the clinical studies published from the day the datebases were set up to July 2018 on detecting microRNAs as biomarkers in the diagnosis of nasopharyngeal carcinoma were collected. Literature selection, data extraction and literature quality evaluation were carried out according to the criteria of exclusion and inclusion.Then Meta-disc,Stata,and other softwares were used for the Meta-analysis. Result:Eighteen eligible articles were collected for systematic review, of which 7 independent case-control studies from 6 articles including 706 NPC patients and 353 controls were selected in the Meta-analysis. Since the obvious heterogeneity among the studies was observed,we conducted this Meta-analysis by the random effect model. The pool sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and area under curve of circulating microRNAs in the diagnosis of nasopharyngeal carcinoma were 0.78（95%CI: 0.75-0.81, 0.81(95%CI: 0.77-0.85), 5.71(95%CI: 2.49-13.11), 0.23(95%CI: 0.13-0.42), 30.88(95%CI: 7.91-120.59) and 0.913 1,which illustrated the high diagnostic accuracy and significant clinical utility of microRNAs in the diagnosis of nasopharyngeal carcinoma.Subgroup analysis showed that the source of samples,the number of cases,the amount of the detecting microRNAs and the type of control groups were the main reasons contributing to the significant heterogeneity. Conclusion:MicroRNAs as biomarkers in the diagnosis of nasopharyngeal carcinoma possess significant potential value. .

A novel double-variant RHAG allele leads to Rhmod phenotype

AIMS/OBJECTIVES

We aimed to analyse the molecular backgrounds and red blood cell (RBC) antigen expression of a male blood donor with Rh_mod phenotype and his family members.

BACKGROUND

Rh deficiency phenotypes are rarely found worldwide and are characterised by the lack of Rh antigen expression on RBCs. During routine screening, we found a blood donor who seemingly lacked Rh antigens. Therefore, we recruited the donor and his family for further investigation.

METHODS

RBC serotyping and antibody screening/identification were performed for each sample. A routine blood examination was also conducted. RHD, RHCE and RHAG were sequenced at the genomic DNA or RNA level. Eleven antigens or proteins associated with Rh complex were tested using flow cytometry analysis.

RESULTS

The proband and one of his brothers showed extremely weak D antigen and Rh expression levels but did not manifest anaemia. Most of the expressed RBC antigens of the two Rh-deficient individuals were similar to the previously reported cases but with some exceptions. Molecular analyses demonstrated homozygous expression of a novel RHAG allele, namely, c.[572G>A;707A>C], both in the proband and one of his brothers.

CONCLUSIONS

To our knowledge, we identified the second double-variant RHAG allele and the first one related to Rh_mod phenotype. The novel allele was also confirmed to be heritable by family analyses.

Human Bone Marrow Mesenchymal Stem Cells Rescue Endothelial Cells Experiencing Chemotherapy Stress by Mitochondrial Transfer Via Tunneling Nanotubes

Tunneling nanotubes (TNTs) are newly discovered tubular structures between two distant cells that facilitate the intercellular exchange of signals and components. Recent reports show that mesenchymal stem cells (MSCs) can rescue injured target cells and promote recovery from a variety of stresses via TNT-mediated mitochondrial transfer. In this study, we explored how TNTs form between bone marrow MSCs and endothelial cells (ECs) by using a human umbilical cord vein endothelial cell (HUVEC) model. TNT formation between MSCs and HUVECs could be induced by treating HUVECs with cytarabine (Ara-C), and human bone marrow mesenchymal stem cells (hBMMSCs) could transfer mitochondria to injured HUVECs through TNTs. Mitochondrial transfer from hBMMSCs to HUVECs via TNTs rescued the injured HUVECs by reducing apoptosis, promoting proliferation and restoring the transmembrane migration ability as well as the capillary angiogenic capacity of HUVECs. This study provides novel insights into the cell-cell communication between MSCs and ECs and supports the results of prior studies indicating that ECs promote hematopoietic regeneration. An improved understanding of MSC-EC cross-talk will promote the development of MSC-directed strategies for improving EC function and hematopoietic system regeneration following myelosuppressive and myeloablative injuries.