Abstract: Due to the continued emergence of multiple variants of SARS-CoV-2, the ongoing pandemic has resulted in severe mortality over the past two years. After the Alpha, Beta, Gamma and Delta variants, the most recent new variant of concern (VOC) strain to emerge is Omicron (B.1.1.529), which evolved as a result of the accumulation of a large number of mutations. The Omicron variant, which has a much higher transmission rate than the Delta variant, soon replaced the Delta variant and others, is now the dominant variant worldwide. The emergence of Omicron poses new challenges for the prevention and control of COVID-19 and has raised a number of concerns worldwide. Recently, cases of Omicron infection have been reported in several parts of China, and therefore this paper provides a comprehensive analysis and summary of the epidemiology and immune escape mechanisms of the Omicron variant. We also suggest some therapeutic strategies against the Omicron variant, including rapid diagnosis, genome analysis of emerging variants, ramping up of vaccination drives and receiving booster doses, updating the available vaccines, designing of multivalent vaccines able to generate hybrid immunity, up-gradation of medical facilities and strict implementation of adequate prevention and control measures need to be given high priority to handle the on-going COVID-19 pandemic successfully.

Polycomb group (PcG) proteins are a family of epigenetic regulators responsible for the repression of genes in proliferation and differentiation of stem cells. PcG protein complex consists of two important epigenetic regulators: PRC1 (polycomb repressive complex 1) and PRC2 (polycomb repressive complex 2). In order to further understand the functions of PcG proteins in stem cell growth and differentiation, we review the PcG protein composition, PcG protein localization in the target gene, PcG protein recruitment, and the functions of PcG proteins in the development of stem cells.
Cell Differentiation ; physiology ; Cell Proliferation ; Humans ; Polycomb Repressive Complex 1 ; metabolism ; physiology ; Polycomb Repressive Complex 2 ; metabolism ; physiology ; Polycomb-Group Proteins ; metabolism ; physiology ; Stem Cells ; cytology ; metabolism

Objective To evaluate the feasibility and safety in the treatment of liver cancer located under the diaphragm with cool-tip radiofrequency ablation(RFA)percutaneously under CT guidance.Methods 20 patients with total 25 lesions were treated by CT-guided RFA with cool-tip electrode involving the induced necroses.The postoperative efficacy was evaluated by enhanced CT or MRI.Results 72% lesions were completely necrotized(18/25),28% lesions were majorly necrotized(7/25).No severe complications occurred. Conclusion CT-RFA with cool-tip electrode is effective and safe in treating liver cancer located under the diaphragm.

Objective To investigate the diagnostic criteria of thyroid solid nodules by high-frequency ultrasound,elastography and ultrasound contrast.Methods Totally 87 patients with thyroid solid nodules underwent high-frequency ultrasound,elastography and ultrasound contrast before surgery,distinguishing benign from malignant lesions was executed based on pathological results,and according to the pathological character the image features by the three measures were compared.There were 40 patients divided into a control group going through the examination by high-frequency ultrasound,and 47 ones into an observation group with the examinations by the three measures.Pathological results were used as gold standard,and the two groups were compared on diagnostic sensitivity.Results High-frequency ultrasound showed significant differences of benign and malignant nodules in equal echo,very low echo,irregular peripheral halo,rates of clear nodule boundary and aspect ratio higher than as well as microcalcification (x2--4.603,17.394,5.833,14.832,10.107 and 27.392,and all Pvalues were less than 0.05).There were 85％ benign nodules gained grade Ⅰ and Ⅱ elastography images,81.82％malignant nodules had grade Ⅲ and ⅣV elastography images,and there were significant differences between benign and malignant nodules (x2=53.42,P=0.00).Ultrasound contrast found annular enhancement in most of benign nodules (x2=39.16,P＜0.01) while uneven enhancement in most of malignant nodules (x2=40.28,P＜0.01),and the nodule ranges increasedsignificantly after contrast (t=2.19,P＜0.05).The observation group had the sensitivity being 82.86％,which was statisticallyhigher than 59.38％ in the control group (x2=4.537,P--0.033).Conclusion High-frequency ultrasound,elastography and ultrasound contrast all show the manifestations of thyroid solid nodules,and the comprehensive application of the above three measures contributes to determining the nature of the nodules.

Objective To evaluate the diagnostic significance of PLA2R and IgG4 in elderly patients with idiopathic membranous nephropathy (IMN).Methods The clinical data were retrospectively analyzed of patients with IMN (49 males and 49 females,aged 66.6 ± 5.4 years) or Non-IMN (57 males and 41 females,aged 67.1 ± 6.5 years) who were admitted in the authors served Department of Nephrology from Apr.2014 to Feb.2016 and accepted renal biopsy.SPSS13.0 was employed to evaluate the sensitivity,specificity and calculate the area under ROC curve (AUC) of serum anti-PLA2R antibody,glomerular PLA2R and IgG1-4 subclasses on diagnosing IMN.Results On diagnosing IMN,the sensitivity and specificity of serum anti-PLA2R antibody were 77.6％ and 89.8％ [AUC=0.869(0.816-0.923)],of glomerular PLA2R were 66.3％ and 94.9％ [AUC=0.805(0.741-0.87)],and of glomerular IgGl-IgG4 were 80.6％ and 78.6％,60.2％ and 83.7％,41.8％ and 84.7％,and 93.9％ and 89.8％,respectively [AUC=0.767(0.696-0.838),0.709(0.635-0.783),0.628(0.549-0.706) and 0.94(0.901-0.978),respectively].As to the combined use of glomerular PLA2R and IgG4 on diagnosing IMN,the sensitivity was 93.9％ when either one of glomerular PLA2R and IgG4 was positive,or the specificity was 96.9％ when both glomerular PLA2R and IgG4 were positive.Conclusion PLA2R and IgG4 can effectively serve the diagnosis of IMN,and the combined use of PLA2R and IgG4 may be better than single indicator alone.

OBJECTIVETo investigate the effect of ethyl pyruvate (EP) on high mobility group box-1 protein (HMGB1) expression in renal tissue and acute kidney injury in rats with delayed resuscitation after thermal injury.

METHODSSeventy-eight Wistar rats subjected to 30% total body surface area full-thickness thermal injury followed with delayed resuscitation were divided into 3 groups: sham group (n = 18), injury group (n = 30) and EP group (n = 30). Renal tissue and blood samples were harvested to determine HMGB1 mRNA as well as its protein expression and renal function parameter at the 8, 24, 72 h post the "injury". HMGB1 mRNA was semi-quantitatively measured by reverse transcription polymerase chain reaction taking GAPDH as an internal standard, and HMGB1 protein expression was determined by Western blot and immunohistochemistry. Blood urea nitrogen (BUN) levels were measured with automatic biochemistry analyzer. The pathological changes of renal tissues were examined using HE staining.

RESULTSCompared with sham controls, both mRNA and protein expressions of HMGB1 in injury group were significantly enhanced in kidneys at 8 - 72 h after thermal injury (P < 0.05), meanwhile serum BUN levels were markedly increased (P < 0.05). Compared with injury group, the renal HMGB1 mRNA and protein expressions were markedly down-regulated in EP group at 8 h, 24 h and 72 h post injury (P < 0.05), respectively, and meanwhile serum BUN levels were reduced significantly (P < 0.05). Inflammatory cell infiltration was found in renal tissues following injury, and kidney injury was markedly alleviated after treatment with EP.

CONCLUSIONSIt indicated that HMGB1 appears to be involved in the pathogenesis of post-burn acute kidney injury. Treatment with EP reduces renal HMGB1 expression, and protects against acute kidney injury secondary to delayed resuscitation after major burns.

Acute Disease ; Animals ; Blood Urea Nitrogen ; Blotting, Western ; Burns ; blood ; physiopathology ; therapy ; Disease Models, Animal ; HMGB1 Protein ; genetics ; metabolism ; Immunohistochemistry ; Kidney ; drug effects ; metabolism ; pathology ; Kidney Diseases ; genetics ; metabolism ; physiopathology ; Male ; Pyruvates ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Resuscitation ; Reverse Transcriptase Polymerase Chain Reaction ; Time Factors

OBJECTIVETo explore the association between mortality rate of hepatic carcinoma and the distance from Suihe River in Lingbi county, Suzhou, Anhui province.

METHODSUsing the disease mapping and spatial statistical analysis techniques,we described the spatial distributions of the mortality rate of hepatic carcinoma from 2005 to 2010 in Lingbi county. Taking the distance between villages and polluted rivers as proxy variable of environmental exposure, mortality rate of hepatic carcinoma in each village as dependant variable, and using the Glimmix model and Bayesian spatial model (BYM) to undertake the univariate and multivariate analysis, we investigatived the association between mortality rate of hepatic carcinoma and the water pollution of Suihe River in Lingbi county.

RESULTSObvious clustering of high mortality rate of hepatic carcinoma along the polluted river was observed in Lingbi county. Results of Glimmix model showed that whether spatial autocorrelation was considered or not, closer to the polluted river has higher mortality rate of hepatic carcinoma. Results of univariate analysis of the BYM model showed that, compared with the villages far from the polluted river more than 12 km (the mortality rate of hepatic carcinoma was 33.12/100 000(1068/3 224 562) ), the RR values of the hepatic carcinoma mortality was 1.38(95%CI:1.06-1.82) for the villages apart from the polluted river within 6 km (the mortality rate of hepatic carcinoma was 42.48/100 000(777/1 829 064)), and 1.13 (95%CI:0.92-1.39) for villages apart from the river between 6 and 12 km (the mortality rate of hepatic carcinoma was 35.65/100 000(651/1 825 848)). In the BYM model multivariate analysis, adding the volume of fertilizer and pesticides used per cultivated area, GDP per capita to do multivariate analysis were, the relation between mortality rate of hepatic carcinoma and distance from polluted rivers remains unchanged.

CONCLUSIONThe mortality rate of hepatic carcinoma was associated with the exposure to the polluted river in Lingbi county. The polluted river may increase the hepatic carcinoma mortality of nearby residents.

Bayes Theorem ; China ; epidemiology ; Environmental Exposure ; Female ; Humans ; Liver Neoplasms ; epidemiology ; mortality ; Male ; Rivers ; Spatial Analysis ; Water Pollution

OBJECTIVETo determine the effect of national free highly active antiretroviral treatment (HAART) on reduction of mortality and relevant risk factors among adult Acquired immunodeficiency syndrome (AIDS) patients.

METHODSA retrospective cohort study was conducted and all AIDS patients diagnosed before Aug. 30th, 2008 in Zhumadian, Henan province, and Fuyang, Anhui province were enrolled in this study, where HAART initiated in early time. The data and information were collected such as AIDS progress, diagnosis, treatment, death and et al.

RESULTSAmong 10,394 AIDS patients, the mean age was (41.7 +/- 9.3) year-old, 50.3% (5233/10,394) were male, 85.0% (8808/10,394) were married, 95.1% (9880/10,394) were farmers, and 81.2% (8438/10,394) were former plasma donors (FPDs). The coverage of HAART increased from 5.2% in 2002 to 66.5% in 2008. Conversely, the overall mortality declined from 35.4/100 person-years in 2002 to 5.9/100 person-years in 2008. In a multivariate Cox proportional hazards analysis, the greatest risk factor for mortality was non-HAART, with a hazard ratio (HR) 4.3 (95%CI: 4.0 - 4.7). Among treated patients, compared with higher CD(4)(+) T cell counts (> 200 cells/microl), those initiating therapy with lower CD(4)(+) T cell counts, were at greater risk to death (< 50 cells/microl, HR = 7.9; 50 - 199 cells/microl, HR = 2.8). Number of opportunistic infections (OIs) was risk to mortality (HR = 2.1). In addition, other risk factors included male, age (>or= 50 years old), and other infection way except FPDs (HR were 1.4, 1.6 and 1.8).

CONCLUSIONThe national free treatment program has significantly reduced the AIDS mortality rate among HIV-infected FPDs through the use of generic antiretroviral drugs in rural clinical settings. The effective reduction of AIDS mortality could be realized through increased coverage of therapy.

Acquired Immunodeficiency Syndrome ; drug therapy ; economics ; mortality ; Adult ; Anti-HIV Agents ; economics ; therapeutic use ; Antiretroviral Therapy, Highly Active ; economics ; utilization ; China ; Cohort Studies ; Female ; Humans ; Inpatients ; Male ; Middle Aged ; Retrospective Studies ; Survival Rate

OBJECTIVETo evaluate four candidate variable number tandem repeat (VNTR) loci for genotyping Mycobacterium tuberculosis complex strains.

METHODSGenomic sequences for two M. tuberculosis strains (CCDC5079 and CCDC5180) were generated, and using published sequence data, four candidate VNTR loci were identified. The VNTRs were used to genotype 225 Chinese clinical M. tuberculosis complex strains. The discriminatory power of the VNTRs was evaluated using BioNumerics 5.0 software.

RESULTSThe Hunter-Gaston Index (HGI) for BJ1, BJ2, BJ3, and BJ4 loci was 0.634, 0.917, 0.697, and 0.910, respectively. Combining all four loci gave an HGI value of 0.995, thus confirming that the genotyping had good discriminatory power. The HGI values for BJ1, BJ2, BJ3, and BJ4, obtained from Beijing family strain genotyping, were 0.447, 0.878, 0.315, and 0.850, respectively. Combining all four loci produced an HGI value of 0.988 for genotyping the Beijing family strains. We observed unique patterns for M. bovis and M. africanum strains from the four loci.

CONCLUSIONWe have shown that the four VNTR loci can be successfully used for genotyping M. tuberculosis complex strains. Notably, these new loci may provide additional information about Chinese M. tuberculosis isolates than that currently afforded by established VNTR loci typing.

Cluster Analysis ; Genotyping Techniques ; Humans ; Minisatellite Repeats ; Mycobacterium bovis ; genetics ; Mycobacterium tuberculosis ; genetics

BACKGROUNDTreatment of ischemic heart disease remains an important challenge, though there have been enormous progresses in cardiovascular therapeutics. This study was conducted to evaluate whether Tongxinluo (TXL) treatment around the transplantation of mesenchymal stem cells (MSCs) can improve survival and subsequent activities of implanted cells in swine hearts with acute myocardial infarction (AMI) and reperfusion.

METHODSTwenty-eight Chinese mini-pigs were divided into four groups including a control group (n = 7); group 2, administration of low-dose TXL alone from the 3rd day prior to AMI to the 4th day post transplantation (n = 7); group 3, MSCs alone (n = 7) and group 4, TXL + MSCs (n = 7). AMI models were made by occlusion of the left anterior descending coronary artery for 90 minutes. Autologous bone marrow-MSCs (3 x 10(7) cells/animal) were then injected into the post-infarct myocardium immediately after AMI and reperfusion. The survival and differentiation of implanted cells in vivo were detected by immunofluorescent analysis. The data of cardiac function were obtained at baseline (1 week after transplantation) and endpoint (6 weeks after transplantation) by single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI). Apoptosis was detected by TUNEL assay and the oxidative stress level was investigated in the post-infarct myocardium at endpoint.

RESULTSAt endpoint, there was less fibrosis and inflammatory cell infiltration with more surviving myocardium in group 4 than in the control group. In group 4 the survival and differentiation of implanted MSCs were significantly improved more than that seen in group 3 alone (P < 0.0001); the capillary density was also significantly greater than in the control group, group 2 or 3 both in the infarcted zone (P < 0.0001) and the peri-infarct zone (P < 0.0001). MRI showed that parameters at baseline were not significantly different between the 4 groups. At endpoint, regional wall thickening and the left ventricular ejection fraction were increased while the left ventricular mass index, dyskinetic segments and infarcted size were decreased only in group 4 compared with control group (P < 0.0001). SPECT showed that the area of perfusion defect was significantly decreased at endpoint only in group 4 compared with control group (P < 0.0001). TUNEL assay indicated that TXL administration significantly decreased cell apoptosis in peri-infarct myocardium in groups 2 and 4. Furthermore, superoxide dismutase (SOD) significantly increased and malondialdehyde (MDA) decreased in groups 2 and 4 by the administration of TXL.

CONCLUSIONSOur study demonstrates the following: (1) immediate intramyocardial injection of MSCs after AMI and reperfusion resulted in limited survival and differentiation potential of implanted cells in vivo, thus being incapable of beneficially affecting post-hearts; (2) TXL-facilitation resulted in a significant survival and differentiation potential of implanted cells in vivo via inhibition of apoptosis and oxidative stress, accompanied by significant benefits in cardiac function.

Animals ; Apoptosis ; Cardiomyoplasty ; methods ; Drugs, Chinese Herbal ; therapeutic use ; Magnetic Resonance Imaging ; Mesenchymal Stem Cell Transplantation ; Myocardial Infarction ; pathology ; therapy ; Myocardium ; pathology ; Oxidative Stress ; Swine ; Swine, Miniature ; Tomography, Emission-Computed, Single-Photon ; Transplantation, Autologous