[Erdheim-Chester disease initially discovered at extraskeletal locations: a clinicopathological analysis of four cases]

Objective: To investigate the clinicopathological features of Erdheim-Chester disease (ECD) initially diagnosed at extraskeletal locations. Methods: Clinical and pathological data of four cases of ECD diagnosed initially in extraskeletal locations were collected at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, from January 2013 to June 2023. BRAF V600E gene was detected by reverse transcription polymerase chain reaction (RT-PCR). Pertinent literatures were reviewed. Results: Four ECD patients included two males and two females ranging in ages from 2 years 11 months to 69 years. The lesions located in the lung (two cases), central nervous system (one case), and the testicle (one case) were collected in the study. One patient had occasional fever at night, one had nausea and vomiting, and two were asymptomatic. Radiologically, the two pulmonary ECD showed diffuse ground-glass nodules in both lungs, and the lesions in central nervous system and testicle both showed solid masses. Microscopically, there were infiltration of foamy histiocyte-like cells and multinucleated giant cells in a fibrotic background, accompanied by varying amounts of lymphocytes and plasma cells. The infiltration of tumor cells in pulmonary ECD was mainly seen in the subpleural area, interlobular septa, and perivascular and peribronchiolar areas. The fibrosis was more pronounced in the pleura and interlobular septa, and less pronounced in the alveolar septa. Immunohistochemical staining showed that all tumor cells expressed CD68, CD163 and F􀃼a; one case showed S-100 expression; three cases were positive for BRAF V600E; all were negative for CD1α and Langerin. RT-PCR in all four cases showed BRAF V600E gene mutation. Conclusions: Extraskeletal ECD is often rare and occult, and could be easily misdiagnosed, requiring biopsy confirmation. The radiologic findings of pulmonary ECD is significantly different from other types of ECD, and the histopathological features of pronounced infiltration in the subpleura area, interlobular septa, perivascular and peribronchiolar areas can be helpful in the differential diagnosis from other pulmonary diseases. Detection of BRAF V600E gene mutation by RT-PCR and its expression by immunohistochemical staining are also helpful in the diagnosis.

Floating-Point Approximation Enabling Cost-Effective and High-Precision Digital Implementation of FitzHugh-Nagumo Neural Networks

The study of neuron interactions and hardware implementations are crucial research directions in neuroscience, particularly in developing large-scale biological neural networks. The FitzHugh-Nagumo (FHN) model is a popular neuron model with highly biological plausibility, but its complexity makes it difficult to apply at scale. This paper presents a cost-saving and improved precision approximation algorithm for the digital implementation of the FHN model. By converting the computational data into floating-point numbers, the original multiplication calculations are replaced by adding the floating-point exponent part and fitting the mantissa part with piecewise linear. In the hardware implementation, shifters and adders are used, greatly reducing resource overhead. Implementing FHN neurons by this approximation calculations on FPGA reduces the normalized root mean square error (RMSE) to 3.5% of the state-of-the-art (SOTA) while maintaining a performance overhead ratio improvement of 1.09 times. Compared to implementations based on approximate multipliers, the proposed method achieves a 20% reduction in error at the cost of a 2.8% increase in overhead.This model gained additional biological properties compared to LIF while reducing the deployment scale by only 9%. Furthermore, the hardware implementation of nine coupled circular networks with eight nodes and directional diffusion was carried out to demonstrate the algorithm's effectiveness on neural networks. The error decreased to 60% compared to the single neuron of the SOTA. This hardware-friendly algorithm allows for the low-cost implementation of high-precision hardware simulation, providing a novel perspective for studying large-scale, biologically plausible neural networks.

Novel Stereo-Induction Pattern in Pudovik Addition/Phospha-Brook Rearrangement Towards Chiral Trisubstituted Allenes

Despite the significance of chiral allene skeletons in catalysis, organic synthesis and medicinal chemistry et al., there is a scarcity of reports on axially chiral allenyl phosphorus compounds. Here, we disclosed an efficient and straightforward cascade reaction between ethynyl ketones and phosphine oxides, resulting in a broad array of trisubstituted allenes incorporating a phosphorus moiety in high yields with excellent stereoselectivities facilitated by peptide-mimic phosphonium salt (PPS) catalysis, Additionally, comprehensive series of mechanistic experiments have been conducted to elucidate that this cascade reaction proceeds via an asymmetric Pudovik addition reaction followed by a subsequent phospha-Brook rearrangement that occurs concomitantly with kinetic resolution, representing a stereospecific rearrangement and protonation process facilitating central-to-axial chirality transfer in a cascade manner. We anticipate that our research will pave the way for a promising exploration of novel stereo-induction pattern in the Pudovik addition/phospha-Brook rearrangement cascade reaction.

[Advances of pathological diagnosis and molecular pathology of lung neuroendocrine neoplasms]

The pathological classification and diagnostic criteria for lung neuroendocrine neoplasms (NENs) in the 2021 World Health Organization (WHO) lung tumor classification are similar to the prior classifications. However, the advances on the molecular studies of lung NENs have shown that both small cell lung carcinoma and large cell neuroendocrine carcinoma are highly heterogeneous tumors with neuroendocrine characteristics and can be subclassified based on the features of genomics or transcriptomics, which are valuable in the diagnosis of lung NENs subtypes and patient treatment. In addition, it is necessary to interpret emerging concepts such as "lung neuroendocrine tumor G3" and "histological transformation" from pathological perspectives, as well as to know the novel neuroendocrine biomarkers such as INSM1 and POU2F3. This article summarized the diagnostic changes and the advances of molecular pathology of lung NENs based on the latest WHO classification and molecular research.

Organocatalytic Dynamic Kinetic Resolution Enabled Asymmetric Synthesis of Phosphorus-Containing Chiral Helicenes

The catalytic asymmetric synthesis of phosphorus-containing helicenes remains a formidable challenge, presumably due to the lack of rational design of substrates, right choice of reactions together with highly effective catalysis systems. Herein, we disclosed an efficient and practical DKR-involving (dynamic kinetic resolution) cascade strategy toward synthesizing a novel family of phosphorus-installing helicenes by peptide-mimic phosphonium salt (PPS) catalysis. The sequential process of PPS-catalyzed phospha-Michael attack and copper salt-facilitated aromatization led to the formation of unprecedented phosphorus-containing oxa[5]helicene scaffolds. A wide variety of substrates bearing an assortment of functional groups were compatible with this protocol, furnishing the expected helical compounds in high yields and excellent stereoselectivities. Additionally, the helical products could be conveniently elaborated to promising phosphine ligands with perfectly retained helical chirality, which turned out to be highly efficient chiral ligands in transition metal-catalyzed reactions. These findings not only expand the current library of phosphorus-containing helicenes but also offer insights to explore other challenging scaffolds with molecular chirality.

The flavonoids induce the transcription of mRNA encoding erythropoietin in cultured embryonic stem cells via the accumulation of hypoxia-inducible factor-1α

Flavonoids are the most common phytochemicals in vegetables and herbal products. The beneficial functions of flavonoids in the brain and erythropoietic system have been proposed. Erythropoietin (EPO) is a potent protective agent in the brain; but which has difficulty to cross the blood brain barrier (BBB). Here, about 60 flavonoids were screened for their potential activation on the transcription of EPO mRNA in the neuronal embryonic stem cell lines, NT2/D1 and PC12. Amongst the screened flavonoids, formononetin, calycosin, ononin, chrysin, baicalein and apigenin showed robust up regulation of EPO production via enhancement of hypoxia response element (HRE) activity in cultured embryonic stem cells. In addition, the flavonoids showed activation of HRE activity by having increased accumulation of HIF-1α, but not on level of HIF-1β, in the cultures. The accumulation of HIF-1α was attributed to up regulation of HIF-1α mRNA and blockade of HIF-1α degradation upon treatment of the flavonoids. These results suggested a promising trend of developing commercial products of flavonoids as food supplements tailored for brain health.

[Analysis of dyslipidemia management status in atrial fibrillation patients with very high and high risk of atherosclerotic cardiovascular disease]

Objective: To analyze the status of statins use and low-density lipoprotein cholesterol (LDL-C) management in patients with atrial fibrillation (AF) and very high/high risk of atherosclerotic cardiovascular disease (ASCVD) from Chinese Atrial Fibrillation Registry (CAFR). Methods: A total of 9 119 patients with AF were recruited in CAFR between January 1, 2015 to December 31, 2018, patients at very high and high risk of ASCVD were included in this study. Demographics, medical history, cardiovascular risk factors, and laboratory test results were collected. In patients with very high-risk, a threshold of 1.8 mmol/L was used as LDL-C management target and in patients with high risk, a threshold of 2.6 mmol/L was used as LDL-C management target. Statins use and LDL-C compliance rate were analyzed, multiple regression analysis was performed to explore the influencing factors of statins use. Results: 3 833 patients were selected (1 912 (21.0%) in very high risk of ASCVD group and 1 921 (21.1%) in high risk of ASCVD group). The proportion of patients with very high and high risk of ASCVD taking statins was 60.2% (1 151/1 912) and 38.6% (741/1 921), respectively. Attainment rate of LDL-C management target in patients with very high and high risk were 26.7% (511/1 912) and 36.4% (700/1 921), respectively. Conclusion: The proportion of statins use and attainment rate of LDL-C management target are low in AF patients with very high and high risk of ASCVD in this cohort. The comprehensive management in AF patients should be further strengthened, especially the primary prevention of cardiovascular disease in AF patients with very high and high risk of ASCVD.

[Metformin use and risk of ischemic stroke in patients with type 2 diabetes: A cohort study]

OBJECTIVE

To explore the association between the use of metformin and the risk of ischemic stroke in patients with type 2 diabetes.

METHODS

A prospective cohort study was designed from the Fangshan family cohort in Beijing. According to metformin use at baseline, 2 625 patients with type 2 diabetes in Fangshan, Beijing were divided into metformin group or non-metformin group and the incidence of ischemic stroke between the different groups during follow-up was estimated and compared by Cox proportional hazard regression model. The participants with metformin were first compared with all the parti-cipants who did not use metformin, and then were further compared with those who did not use hypoglycemic agents and those who used other hypoglycemic agents.

RESULTS

The patients with type 2 diabetes were with an average age of (59.5±8.7) years, and 41.9% of them were male. The median follow-up time was 4.5 years. A total of 84 patients developed ischemic stroke during follow-up, with a crude incidence of 6.4 (95%CI: 5.0-7.7) per 1 000 person-years. Among all the participants, 1 149 (43.8%) took metformin, 1 476 (56.2%) were metformin non-users, including 593 (22.6%) used other hypoglycemic agents, and 883 (33.6%) did not use any hypoglycemic agents. Compared with metformin non-users, the Hazard ratio (HR) for ischemic stroke in metformin users was 0.58 (95%CI: 0.36-0.93; P = 0.024). Compared with other hypoglycemic agents, HR was 0.48 (95%CI: 0.28-0.84; P < 0.01); Compared with the group without hypoglycemic agents, HR was 0.65 (95%CI: 0.37-1.13; P=0.13). The association between metformin and ischemic stroke was statistically significant in the patients ≥ 60 years old compared with all the metformin non-users and those who used other hypoglycemic agents (HR: 0.48, 95%CI: 0.25-0.92; P < 0.05). Metformin use was associated with a lower incidence of ischemic stroke in the patients with good glycemic control (0.32, 95%CI: 0.13-0.77; P < 0.05). In the patients with poor glycemic control, and the association was not statistically significant (HR: 0.97, 95%CI: 0.53-1.79; P>0.05). There was an interaction between glycemic control and metformin use on incidence of ischemic stroke (P_interaction < 0.05). The results of the sensitivity analysis were consistent with the results in the main analysis.

CONCLUSION

Among patients with type 2 diabetic in rural areas of northern China, metformin use was associated with lower incidence of ischemic stroke, especially in patients older than 60 years. There was an interaction between glycemic control and metformin use in the incidence of ischemic stroke.

[Current use of oral anticoagulation therapy and influencing factors among coronary artery disease patients with nonvalvular atrial fibrillation in China]

Objective: To investigate current use of oral anticoagulant (OAC) therapy and influencing factors among coronary artery disease (CAD) patients with nonvalvular atrial fibrillation (NVAF) in China. Methods: Results of this study derived from "China Atrial Fibrillation Registry Study", the study prospectively enrolled atrial fibrillation (AF) patients from 31 hospitals, and patients with valvular AF or treated with catheter ablation were excluded. Baseline data such as age, sex and type of atrial fibrillation were collected, and drug history, history of concomitant diseases, laboratory results and echocardiography results were recorded. CHA₂DS₂-VASc score and HAS-BLED score were calculated. The patients were followed up at the 3rd and 6th months after enrollment and every 6 months thereafter. Patients were divided according to whether they had coronary artery disease and whether they took OAC. Results: 11 067 NVAF patients fulfilling guideline criteria for OAC treatment were included in this study, including 1 837 patients with CAD. 95.4% of NVAF patients with CAD had CHA₂DS₂-VASc score≥2, and 59.7% of patients had HAS-BLED≥3, which was significantly higher than NVAF patients without CAD (P<0.001). Only 34.6% of NVAF patients with CAD were treated with OAC at enrollment. The proportion of HAS-BLED≥3 in the OAC group was significantly lower than in the no-OAC group (36.7% vs. 71.8%, P<0.001). After adjustment with multivariable logistic regression analysis, thromboembolism(OR=2.48,95%CI 1.50-4.10,P<0.001), left atrial diameter≥40 mm(OR=1.89,95%CI 1.23-2.91,P=0.004), stain use (OR=1.83,95%CI 1.01-3.03, P=0.020) and β blocker use (OR=1.74,95%CI 1.13-2.68,P=0.012)were influence factors of OAC treatment. However, the influence factors of no-OAC use were female(OR=0.54,95%CI 0.34-0.86,P=0.001), HAS-BLED≥3 (OR=0.33,95%CI 0.19-0.57,P<0.001), and antiplatelet drug(OR=0.04,95%CI 0.03-0.07,P<0.001). Conclusion: The rate of OAC treatment in NVAF patients with CAD is still low and needs to be further improved. The training and assessment of medical personnel should be strengthened to improve the utilization rate of OAC in these patients.

[Investigation and analysis of late reporting and under-reporting of occupational diseases from 2018 to 2020 in China]

Objective: To understand the late reporting and the under-reporting of occupational disease from 2018 to 2020 in China and analyze the causes, so as to provide scientific evidence for improving the quality of occupational disease reports in China, timely acquiring the incidence of occupational disease, and assessing the occupational hazards. Methods: From May to December 2021, A total of 320 occupational disease diagnostic institutions were selected for investigation. The original documents of occupational disease diagnosis cases from 2018 to 2020 were compared with the online reported cases, and late reported and under-reported cases of occupational disease were analyzed. Results: A total of 32207 diagnosed cases from 2018 to 2020 were investigated, including 28934 confirmed cases and 3273 cases without occupational disease. The overall late reported rate and under-reported rate of confirmed cases were 20.2% and 2.1%, respectively. There were significant differences in the rate of late reporting and under-reporting of occupational diseases in different regions and different types of diagnostic institutions (P<0.001). The southwest region had the highest rates of late reporting and under-reporting, 61.6% and 7.9% respectively. The late reported rate of all kinds of occupational diseases was about 15.0%, and the under-reported rate was from 1.5.0% to 5.0%. Conclusion: At present, the phenomenon of late reporting and under-reporting occupational diseases is still obvious. It is necessary to strengthen the inspection of occupational disease reporting, improve the quality of occupational disease reporting, and provide scientific basis for the formulation of occupational disease prevention and control policies.

Towards Axially Chiral Pyrazole-Based Phosphorus Scaffolds by Dipeptide-Phosphonium Salt Catalysis

Given the comparatively lower rotational barriers, the catalytic asymmetric construction of axially chiral biaryl structures, especially those containing a five-membered heterocycle, still remains a challenge. Herein, we described a general and modular protocol to access atropisomeric arylpyrazole scaffolds containing a phosphorus unit by a dipeptide phosphonium salt catalyzed reaction involving an oxidative central-to-axial chirality conversion. This reaction features excellent yields and enantioselectivities, broad substrate scope, and a low catalyst loading, delivering axially chiral phosphine compounds.

Microbe community composition differences of hand skin on similar lifestyle volunteers: a small-scale study

AIMS

Human skin is the first barrier against pathogens and environmental hazards and the highest contact frequency occurs with the hands. Environmental and personal metabolic factors may affect skin microbes. This study was conducted to clarify the diversity in the skin microbial community that was mainly due to individual skin metabolites rather than lifestyle and environmental factors.

METHODS AND RESULTS

Skin microbiota samples were collected from 11 volunteers who met similar lifestyle inclusion criteria. The V3-V4 region of the 16S rRNA gene was amplified. After library construction and sequencing, we compared the composition and diversity of the hand skin microbiota in different sexes and BMI groups with bioinformation analysis. The whole sequence data were annotated as 42 phyla, 538 families, and 1215 genera. Four dominant phyla accounted for 97% of the total including Actinobacteriota (50.18%), Firmicutes (23.85%), Proteobacteria (21.64%) and Bacteroidota (2.05%). The genera that were detected in all subjects with high relative abundance were Cutibacterium, Staphylococcus, Corynebacterium, Streptococcus, Lawsonella, Enhydrobacter, Escherichia-Shigella, Asaia and Micrococcus.

CONCLUSIONS

The diversity and richness of the microbiota of male hand skin in our study was higher than that of females. Interestingly, Cutibacterium, Staphylococcus, and Corynebacterium might serve as important skin microbiota to distinguish sexes.

[The timing of pericardial drainage catheter removal and restart of the anticoagulation in patients suffered from perioperative pericardial tamponade during atrial fibrillation catheter ablation and uninterrupted dabigatran: Experiences from 20 cases]

Objective: To investigate the timing of pericardial drainage catheter removal and restart of the anticoagulation in patients with atrial fibrillation (AF) suffered from perioperative pericardial tamponade during atrial fibrillation catheter ablation and uninterrupted dabigatran. Methods: A total of 20 patients with pericardial tamponade, who underwent AF catheter ablation with uninterrupted dabigatran in Beijing Anzhen Hospital from January 2019 to August 2021, were included in this retrospective analysis. The clinical characteristics of enrolled patients, information of catheter ablation procedures, pericardial tamponade management, perioperative complications, the timing of pericardial drainage catheter removal and restart of anticoagulation were analyzed. Results: All patients underwent pericardiocentesis and pericardial effusion drainage was successful in all patients. The average drainage volume was (427.8±527.4) ml. Seven cases were treated with idarucizumab, of which 1 patient received surgical repair. The average timing of pericardial drainage catheter removal and restart of anticoagulation in 19 patients without surgical repair was (1.4±0.7) and (0.8±0.4) days, respectively. No new bleeding, embolism and death were reported during hospitalization and within 30 days following hospital discharge. Time of removal of pericardial drainage catheter, restart of anticoagulation and hospital stay were similar between patients treated with idarucizumab or not. Conclusion: It is safe and reasonable to remove pericardial drainage catheter and restart anticoagulation as soon as possible during catheter ablation of atrial fibrillation with uninterrupted dabigatran independent of the idarucizumab use or not in case of confirmed hemostasis.

Genetic screening for hypertension and COVID-19 reveals functional variation of SPEG potentially associated with severe COVID-19 in women

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to more than 6.4 million deaths worldwide. The prevalent comorbidity between hypertension and severe COVID-19 suggests common genetic factors may affect the outcome of both diseases. As both hypertension and severe COVID-19 demonstrate sex-biased prevalence, common genetic factors between the two diseases may display sex-biased differential associations. By evaluating COVID-19 association signals of 172-candidate hypertension single nucleotide polymorphisms (SNPs) derived from more than 1 million European individuals in two sex-stratified severe COVID-19 genome-wide association studies from UK BioBank with European ancestry, we revealed one functional cis expression quantitative trait locus of SPEG (rs12474050) showing sex-biased association with severe COVID-19 in women. The risk allele rs12474050*T associates with higher blood pressure. In our study, we found it is significantly correlated with lower SPEG expression in muscle-skeletal but with higher expression in both brain cerebellum and cerebellar hemisphere. Additionally, nominal significances were detected for the association between rs12474050*T and lower SPEG expression in both heart left ventricle and atrial appendage; among these tissues, the SPEG expression is nominally significantly higher in females than in males. Further analysis revealed SPEG is mainly expressed in cardiomyocytes in heart and is upregulated upon SARS-CoV-2 infection, with significantly higher upregulation of SPEG only observed in female but not in male COVID-19 patients compared to both normal female and male individuals, suggesting upregulation of SPEG is a female-specific protective mechanism against COVID-19 induced heart damage. Taken together, our analyses suggest the involvement of SPEG in both hypertension and severe COVID-19 in women, which provides new insights for sex-biased effect of severe COVID-19 in women.

[The association of high-sensitivity C-reactive protein with new-onset hypertension in different age groups]

Objective: To investigate the association between high sensitivity C-reactive protein (hsCRP) level and new-onset hypertension in different age groups. Methods: This was a prospective cohort study involving non-hypertensive population in Kailuan Group community who participated in health examination between 2006 and 2007.Follow-up was conducted every 2 years, and the time of new onset of hypertension was used as the endpoint of follow-up. The endtime of follow-up for patients without hypertension was the time of death or the last follow-up (December 31, 2017).According to the baseline hsCRP level, the participants were divided into low-risk group (hsCRP<1.0 mg/L), medium-risk group (hsCRP ≥1.0 and ≤3.0 mg/L), and high-risk group (hsCRP>3.0 mg/L), and further stratified by age. Kaplan-Meier method was used to calculate the cumulative incidence of hypertension in each group. Multivariate Cox regression model was used to analyze the association between hsCRP level and new-onset hypertension. Results: A total of 51 179 participants were included in this study, including 38 606 males (75.43%) with an average age of (48.1±12.2) years. The baseline hsCRP was 0.64 (0.25, 1.60) mg/L. The baseline hsCRP was 0.30 (0.16, 0.59), 1.57 (1.20, 2.10), 5.17 (3.80, 7.10) mg/L respectively in low-, medium- and high-risk groups. During the follow-up of (8.1±2.2) years, a total of 9 523 (18.60%) patients developed hypertension, and the cumulative incidence rates of low-, medium- and high-risk groups were 17.41%, 20.48% and 20.73%, respectively. The cumulative incidence of hypertension in low-, medium- and high-risk groups of<45, 45-54, 55-64, ≥65 years old were 13.53%, 15.82%, 16.76%; 19.27%, 22.84%, 21.62%; 21.55%, 24.19%, 24.88%;20.20%, 22.35%, 19.11%, respectively. Except for people aged ≥65 years, there were significant differences in the cumulative incidence of hypertension in low-, medium- and high-risk groups (all P<0.05).Multivariate Cox regression analysis showed that the risk of new-onset hypertension in the high risk group was 1.11 times higher than that in the low risk group (HR=1.11, 95%CI 1.05-1.18). The risk of new-onset hypertension in the high-risk group was 1.22 times (HR=1.22, 95%CI 1.08-1.38), 1.14 times (HR=1.14, 95%CI 1.04-1.26), 1.16 times (HR=1.16, 95%CI 1.04-1.30), and 1.02 times (HR=1.02, 95%CI 0.86-1.20) of the low-risk group, in the<45, 45-54, 55-64, and ≥65 years old groups, respectively. Conclusion: Higher hsCRP level is a risk factor for new-onset hypertension, and the risk of developing hypertension caused by elevated hsCRP is age-dependent.

[A multicenter epidemiological study of acute bacterial meningitis in children]

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.

Enantioselective Synthesis of Atropisomeric Biaryl Phosphorus Compounds by Chiral-Phosphonium-Salt-Enabled Cascade Arene Formation

Axially chiral biaryl monophosphorus molecules, exemplified by atropisomeric 1,1'-biaryl aminophosphines, are significant motifs in numerous chiral ligands/catalysts. Developing efficient methods for preparing phosphorus compounds with these privileged motifs is an important endeavor in synthetic chemistry. Herein, we develop an effective, modular method by a chiral-phosphonium-salt-catalyzed novel cascade between phosphorus-containing nitroolefins and α,α-dicyanoolefins, leading to a great diversity of atropisomeric biaryls bearing phosphorus groups in high yields with excellent stereoselectivities. The reaction features include a Thorpe-type cycloaddition/oxidative hydroxylation/aromatization cascade pathway with a central-to-axial chirality transfer process. Insight gained from our studies is expected to advance general efforts towards the catalytic synthesis of atropisomeric biaryl phosphorus compounds, offering a platform for developing new efficient chiral ligands and catalysts.

[Combined resection of thoracic and abdominal organ clusters: a series of 50 cases]

Objective: To examine the technique and effect of combined thoracic and abdominal organ clusters resection. Methods: From February 2019 to August 2021, totally 50 cases of combined thoracoabdominal organ cluster resection were completed at Transplant Medical Center, the Second Affiliated Hospital of Guangxi Medical University from donation after brain death donors. There were 47 males and 3 females, aging (34.8±12.3) years (range: 5 to 55 years). The length of hospital stay(M(IQR)) was 4(4) days (range: 2 to 43 days), the length of tube time was 4(2) days (range: 1 to 43 days). Through the midsternal incision and the abdominal grand cross incision, the cold perfusion was performing simultaneously when the perfusion lines of each target organ was established respectively. The combined resection was performed with the diaphragm as the boundary and the organ cluster as the unit. The heart and lung were separated on site and sent to the transplant hospital, and the abdominal organ cluster was directly preserved and returned to our hospital for further separation and repair. Results: Totaly 21 hearts, 47 pairs of lungs, 49 livers, 47 pairs of kidneys and 11 pancreas were harvested by this surgical treatment. The resection time was (32.6±6.5) minutes (range: 19 to 50 minutes), with no hot ischemia time. There was no accidental injury that affected organ quality and function. Heart transplantation was performed in 17 cases, combined heart-kidney transplantation in 2 cases, double lung transplantation in 43 cases, single lung transplantation in 6 cases, liver transplantation in 41 cases, combined liver-pancreas-duodenal cluster transplantation in 1 case, combined liver-kidney transplantation in 3 cases, combined pancreas-kidney transplantation in 9 cases, and kidney transplantation in 74 cases. Conclusion: Simultaneous perfusion and combined resection of thoracic and abdominal organ clusters for donation after brain death donors are feasible and effective.

Clinical application of cinematic rendering in maxillofacial fractures

The purpose of this study was to evaluate the clinical application of cinematically rendered reconstructions of maxillofacial fractures. Ten surgeons and eight radiologists were shown three-dimensional images of 25 different patient cases, generated using both the volume rendering (VR) technique and the cinematic rendering (CR) technique. They were asked to mark the site of the fracture on the three-dimensional images and record the time this activity took. The effectiveness of the reconstructions to communicate with patients was assessed through the opinions of the surgeons and radiologists, as well as 25 patients. Subjective evaluations of the clinical value of the images were performed by the 18 surgeons and radiologists using a 10-item questionnaire. The percentages of correctly identified fractures of the nasal bone (P = 0.034), fracture dislocation (P < 0.001), and free bone fragments (P < 0.001) were significantly higher for CR images when compared to VR images, and identification took an average of 20.81 seconds for CR and 27.48 seconds for VR (P < 0.001). CR images were found to be more beneficial for communication with patients and scored higher for the display of fracture dislocation and free bone fragments than VR images (P < 0.05). CR images were found to have high clinical value in the visualization of maxillofacial fractures.

[Effect of electroacupuncture preconditioning on expression of Gasdermin D, Caspase-1 and IL-1β in rats with myocardial ischemia reperfusion injury]

OBJECTIVE

To observe the effect of electroacupuncture(EA) preconditioning on expression of Caspase-1, Gasdermin D(GSDMD) and interleukin-1β(IL-1β) in myocardial tissue of myocardial ischemia reperfusion injury (MIRI) rats in order to explore its underlying mechanisms in resisting MIRI.

METHODS

Forty male rats were randomly divided into 4 groups: normal control (normal), sham operation (sham), MIRI model and EA groups. The MIRI model was established by ligation of the left anterior descending branch of the left coronary artery for 30 min and perfusion. EA (2 Hz/100 Hz, 1 mA) was applied to bilateral "Neiguan" (PC6) for 20 min, once a day for 3 consecutive days. The echocardiography was used to analyze the left ventricular end-diastolic dimension (LVEDD), left ventricular end-systolic dimension (LVESD) and left ventricular ejection fraction (LVEF, by using Teichholz formula) 4 h after modeling. The myocardial TTC staining was used to observe the proportion of the infarct area, and Western blot was used to detect the expression levels of GSDMD, Caspase-1, IL-1β proteins in the myocardium.

RESULTS

Compared with the normal group, the immunoactivity of GSDMD was increased in the sham group (P<0.05). Compared with the sham group, the LVEF was significantly decreased (P<0.000 1), while the myocardial infarction area, immunoactivity of GSDMD, and the expression levels of Caspase-1, GSDMD and IL-1β proteins were considerably increased in the model group (P<0.000 1, P<0.001). In comparison with the model group, the decreased ejection fraction and the increased myocardial infarction area, and Caspase-1, GSDMD and IL-1β expression were reversed in the EA group (P<0.001, P<0.000 1, P<0.01).

CONCLUSION

EA preconditioning may ameliorate myocardial injury in MIRI rats which may be associated with its function in down-regulating the expression of myocardial Caspase-1 protein to reduce cardiomyocyte pyroptosis.

[Application of ureteral access sheath in the operation of middle and lower ureteral calculi in patients with massive benign prostatic hyperplasia]

Objective: To examine the effectiveness and safety of application of the ureteral access sheath in the treatment of middle or lower ureteral calculi in patients with large-volume benign prostatic hyperplasia above grade Ⅲ, which is expected to avoid the simultaneous or staged treatment of benign prostatic hyperplasia via eliminate the difficult angle and resistance of ureteroscopy caused by severe prostatic hyperplasia. Methods: From April 2018 to December 2020, the clinical data of 27 patients with massive benign prostatic hyperplasia above grade Ⅲ and middle and lower ureteral calculi treated with indwelling ureteral access sheath plus ureteroscopy holmium laser lithotripsy at Department of Urology, Zhejiang Quhua Hospital were retrospectively analyzed and followed up. All the patients were male, aged (69.7±12.8) years (range: 55 to 87 years). Prostate volume measured by transrectal ultrasound was (94.8±16.2) cm³ (range: 85 to 186 cm³). The ureteral access sheath was indwelled in advance, and then the semirigid ureteroscopy was introduced through the working channel of the sheath. Holmium laser lithotripsy was performed, and intraoperative and postoperative complications were recorded. Urinary abdominal plain X-ray or CT urography were performed at 1-and 2-month postopaerative to evaluate the residual stones and clinical efficacy. Results: The ureteral access sheath was placed and holmium laser lithotripsy under a semirigid ureteroscopy was performed successfully in all the 27 patients. In 2 patients, a second session of auxiliary procedure was required due to the large load of preoperative stones and residual stones after surgery, among whom 1 patient received extracorporeal shock wave lithotripsy and 1 patient underwent extracorporeal shock wave lithotripsy plus ureteroscopic lithotripsy. The stone free rate at 1-and 2-month postoperative were 92.6% (25/27) and 100% (27/27), respectively. There were no severe complications such as ureteral avulsion and perforation, perirenal hematoma, septic shock, severe hematuria, urinary retention, iatrogenic ureteral stricture occurred during and after the surgery. The ureteral calculus was wrapped by polyps heavily in 1 patient, he was diagnosed as ureteral stenosis 1 month postoperative, receiving laparoscopic resection of ureteral stricture plus anastomosis 3 months postoperative. Conclusions: In the operations of middle and lower ureteral calculi in patients with large-volume prostatic hyperplasia above grade Ⅲ, the ureteral access sheath can be placed first to effectively eliminate the difficult angle and resistance of ureteroscopy caused by severe prostatic hyperplasia, and then semirigid ureteroscopic lithotripsy can be safely performed. It could avoid the treatment of benign prostatic hyperplasia at the same time or by stages.

Genetic Diversity and Selection of Plasmodium vivax Apical Membrane Antigen-1 in China-Myanmar Border of Yunnan Province, China, 2009-2016

Plasmodium vivax apical membrane antigen-1 (PvAMA-1) is an important vaccine candidate for vivax malaria. However, antigenic variation within PvAMA-1 is a major obstacle to the design of a global protective malaria vaccine. In this study, we analyzed the genetic polymorphism and selection of the PvAMA-1 gene from 152 P. vivax isolates from imported cases to China, collected in the China–Myanmar border (CMB) area in Yunnan Province (YP) during 2009–2011 (n = 71) and 2014–2016 (n = 81), in comparison with PvAMA-1 gene information from Myanmar (n = 73), collected from public data. The overall nucleotide diversity of the PvAMA-1 gene from the 152 YP isolates was 0.007 with 76 haplotypes identified (Hd = 0.958). Results from the population structure suggested three groups among the YP and Myanmar isolates with optimized clusters value of K = 7. In addition, YP (2014–2016) isolates generally lacked some K components that were commonly found in YP (2009–2011) and Myanmar. Meanwhile, PvAMA-1 domain I is found to be the dominant target of positive diversifying selection and most mutation loci were found in this domain. The mutation frequencies of D107N/A, R112K/T, K120R, E145A, E277K, and R438H in PvAMA-1 were more than 70% in the YP isolates. In conclusion, high genetic diversity and positive selection were found in the PvAMA-1 gene from YP isolates, which are significant findings for the design and development of PvAMA-1-based malaria vaccine.

Deltamethrin interacts with Culex quinquefasciatus odorant-binding protein: a novel potential resistance mechanism

BACKGROUND

Odorant-binding proteins (OBPs) play important roles in many physiological processes of mosquitoes. Previous high-throughput sequencing studies have revealed that some OBPs of Culex quinquefasciatus might be involved in the development of resistance to insecticides.

METHODS

Based on the results of sequencing analyses, the OBP28 gene was selected for evaluation in this study. Three laboratory strains of Cx. quinquefasciatus [susceptible strain (SS), deltamethrin-resistant strain 1 (HN) and deltamethrin-resistant strain 2 (RR)] were first examined by using the Centers for Disease Control and Prevention bottle bioassay, after which the expression level of the OBP28 gene in the susceptible and deltamethrin-resistant strains was determined by real-time quantitative polymerase chain reaction. The OBP28 gene in deltamethrin-resistant strain RR was silenced using RNA interference technology. The expression level of OBP28 and the resistance level were tested in the silenced strain and control strain after microinjection of double-stranded RNA for a 48-h interference period. Four field-collected strains (henceforth 'field strains') of Cx. quinquefasciatus were also examined for their resistance to deltamethrin and levels of OBP28 expression. Finally, a correlation analysis between deltamethrin resistance and gene expression was carried out for all seven strains, i.e. the four field strains and the three laboratory strains.

RESULTS

In the bioassay, the mortality of SS, HN and RR was 100%, 21.33% and 1.67%, respectively. The relative expression levels of OBP28 in strains HN and RR were 6.30- and 6.86-fold higher, respectively, than that of strain SS. After silencing of the OBP28 gene, the mortality of strain RR was 72.20% and that of the control strain 26.32%. The mortality of strain RR increased significantly after interference compared to that of the control strain. There was a negative correlation between OBP28 gene expression and mortality in adult mosquitoes after exposure to deltamethrin.

CONCLUSIONS

To our knowledge, this study shows for the first time a correlation between the expression of a gene coding for OBP and insecticide resistance in mosquitoes. The potential resistance mechanism that was elucidated provides a new target gene for the surveillance of resistance in mosquitoes.

[Effect of electroacupuncture at "Neiguan" (PC 6) on cardiac function and inflammatory factors of acupoint area in rats with acute myocardial ischemia]

OBJECTIVE

To observe the effect of electroacupuncture (EA) at "Neiguan" (PC 6) on cardiac function and cardiomyocyte apoptosis in rats with acute myocardial ischemia (AMI), and to explore the correlation between myocardial protective effect of EA and inflammatory factors i.e. interleukin-1β (IL-1β) and interleukin-17 (IL-17) of "Neiguan" (PC 6) area.

METHODS

A total of 40 male SD rats with normal ultrasonic cardiogram were randomized into a sham-operation group, a sham-operation plus EA group, a model group and an EA group, 10 rats in each group. The AMI model was established by ligating the left anterior descending (LAD) branch of the coronary artery in the model group and the EA group, while the threading without ligating was adopted in the sham-operation group and the sham-operation plus EA group. In the sham-operation plus EA group and the EA group, EA at bilateral "Neiguan" (PC 6) was applied, with disperse-dense wave, 2 Hz/100 Hz in frequency and 2 mA in density, once a day, 20 min a time for 3 days. The cardiac ejection fraction (EF) and fractional shortening (FS) were measured by ultrasonic cardiogram to evaluate the cardiac function, the cardiomyocyte apoptosis was detected by TUNEL staining, the infiltration of inflammatory factors of "Neiguan" (PC 6) area was observed by H.E. staining, the expression of inflammatory factors IL-1β and IL-17 of "Neiguan" (PC 6) area was detected by immunofluorescence staining.

RESULTS

Compared with the sham-operation group, EF and FS were decreased (P<0.001), the average optical density of cardiomyocyte apoptosis was increased (P<0.001), the infiltration of inflammatory factors was obvious in skin dermis of "Neiguan" (PC 6) area in the model group; the positive expression of IL-1β and IL-17 of "Neiguan" (PC 6) area was increased in the model group and the sham-operation plus EA group (P<0.001, P<0.01). Compared with the model group, EF and FS were increased (P<0.01), the average optical density of cardiomyocyte apoptosis was decreased (P<0.01), the infiltration of inflammatory factors was aggravating in skin dermis of "Neiguan" (PC 6) area, and the positive expression of IL-1β and IL-17 of "Neiguan" (PC 6) area was increased in the EA group (P<0.001, P<0.01).

CONCLUSION

Electroacupuncture at "Neiguan" (PC 6) can improve the cardiac function and reduce the apoptosis of cardiomyocyte in rats with acute myocardial ischemia, its mechanism may be related to the regulation of the inflammatory factors of "Neiguan" (PC 6) area.

[Genotyping analysis of norovirus infectious diarrhea clusters in Songjiang district, Shanghai from 2017 to 2019]

Objective: We aimed to analyze the the genotyping of norovirus infectious diarrhea epidemic in Songjiang district, Shanghai, and explored the experience in handling the epidemic to provide a scientific basis for formulating prevention and treatment strategies. Methods: The epidemiological data and related samples of 69 outbreaks of infectious diarrhea caused by norovirus was collected from 2017 to 2019 in Songjiang district, Shanghai. Sequencing and type identification were performed by the method of gene sequencing for the junction region of Norovirus ORF1 and ORF2. Results: From 2017 to 2019, 69 outbreaks of norovirus infections diarrhea were reported in Songjiang district, Shanghai. A total of 1 767 samples were tested, including 619 case samples (positive rate 19.9%), 343 practitioner samples (positive rate 1.1%), 505 environmental samples (positive rate 0.5%) and 300 food samples (not detected). 141 sequences were obtained, and the genotype analysis showed that the genotype that mainly caused infectious diarrhea in 2017 and 2018 was GII.P16-GII.2 (50.98%, 26/51). In 2019, the genotypes that mainly caused infectious diarrhea were GII.P16-GII.2 (13.73%, 7/51) and GII.Pe-GII.4 (9.80%, 5/51). Conclusion: The main genotype of the 69 outbreaks of nororirus infectious diarrhea epidemic in Songjiang district, Shanghai from 2017 to 2019 was GII.P16-GII.2, which showed obvious peaks in spring, autumn and winter. There were more infections in kindergartens and schools. The surveillance of norovirus infection should be strengthened.

[Safety and effectiveness of left atrial appendage occlusion in patients with atrial fibrillation and end-stage renal disease undergoing long-term hemodialysis]

Objective: To evaluate the safety and effectiveness of left atrial appendage occlusion (LAAO) in patients with atrial fibrillation and end-stage renal disease undergoing long-term hemodialysis. Methods: Six patients with AF and end-stage renal disease(ESRD)on long term hemodialysis who underwent LAAO from March 2017 to March 2021 in Beijing Anzhen Hospital were enrolled. Baseline characteristics such as age, sex, types of arrhythmia, stroke and bleeding score, and continuous dialysis time were collected. Four patients underwent LAAO, two patients underwent the combined procedure of catheter ablation and LAAO. Perioperative treatment and serious complications were recorded. Transesophageal echocardiography was repeated at 45 days and 60 days after the procedure. Telephone follow-up was conducted at 3, 6 and 12 months after the procedure, and every 6 months thereafter. Thromboembolism and major bleeding events and survival were evaluated. Results: The average age was (66.7±17.0) years old, and 5 were male (5/6). There were 4 patients with paroxysmal AF (4/6), and 2 patients with persistent AF (2/6). The mean CHA₂DS₂-VASc score was (4.8±1.5), and the HAS-BLED score was (3.5±1.4). The duration of hemodialysis was 2.6 (1.1, 8.3) years. Successfully Watchman implantation was achieved in all patients. There were no severe perioperative complications, and no device related thrombosis or leaks were observed by transesophageal echocardiography. During a mean of 22.0 (12.0, 32.0) months follow-up, there was no thromboembolism or major bleeding events. A total of 2 patients died, one from sudden cardiac death, and another one from heart failure. Conclusions: LAAO may be a safe and effective therapeutic option for prevention of thromboembolism in patients with atrial fibrillation and end-stage renal disease undergoing long-term hemodialysis, further studies with larger patient cohort are needed to confirm our results.

[Effect of electroacupuncture on expression of IL-23/IL-17 axis and TLR4 in infarcted tissue in rats with myocardial infarction]

OBJECTIVE

To observe the effect of electroacupuncture (EA) on expression of interleukin (IL) -23/IL-17 axis and Toll-like receptor 4 (TLR4) in the infarcted tissue in rats with myocardial infarction (MI), and to explore the mechanism of EA on alleviating MI injury.

METHODS

Forty male SD rats were randomly divided into a sham-operation group, a sham-operation plus EA group, a model group and an EA group, 10 rats in each group. The MI models were established by ligation of left anterior descending coronary artery in the model group and EA group, while only threading was performed in the sham-operation group and sham-operation plus EA group. The rats in the sham-operation plus EA group and EA group were treated with EA at "Neiguan" (PC 6), disperse-dense wave, 2 Hz/100 Hz, 2 mA, once a day, 20 min each time, for 3 days. After the intervention, the ejection fraction (EF) was measured by echocardiography to evaluate the cardiac function; the infarct area was measured by TTC staining; the HE staining was used to observe the morphological changes of myocardial tissue; the levels of IL-23 and IL-17 in infarcted tissue were detected by ELISA; the protein expression of TLR4 in infarcted tissue was detected by Western blot.

RESULTS

Compared with the sham-operation group, the EF was decreased (P<0.01), the infarct area was increased (P<0.01), the myocardial fiber injury was obvious, accompanied by inflammatory cell infiltration, and the contents of IL-23, IL-17 and the expression of TLR4 in infarcted tissue were increased in the model group (P<0.01). Compared with the model group, the EF was increased (P<0.05), the infarct area was reduced (P<0.05), the myocardial fiber injury was significantly improved, the inflammatory cell infiltration was reduced, and the contents of IL-23, IL-17 and TLR4 expression in infarcted tissue were decreased in the EA group (P<0.05).

CONCLUSION

EA may alleviate the excessive inflammatory response after MI by inhibiting the expression of IL-23/IL-17 axis in MI rats, and TLR4 may be involved during the process.

[Current researches and prospects of human induced pluripotent stem cells and gene editing technology of CRISPR/Cas9 in inherited ocular diseases]

Human induced pluripotent stem cells have the ability to differentiate into specific cell types or tissues of the eye in humans and have application prospects in retinal cell transplantation, corneal transplantation, and lens regeneration. Gene editing technology of clustered regularly interspaced short palindromic repeats/crispr-associated protein-9 nuclease (CRISPR/Cas9) can introduce causative mutations of inherited ocular diseases into human induced pluripotent stem cells effectively. Then they can be further differentiated into specific somatic cells maintaining a genetic disease background, which can mimic the occurrence of inherited ocular diseases in vitro. The cell model may help scientists study the mechanism of human disease development, establish an in vitro screening platform to find therapeutic drugs, and correct genetic mutations in the human genome for cell therapy. The combination of stem cells and gene editing technology is revolutionizing the regenerative medicine in ophthalmology and gene therapy of inherited ocular diseases. This review summarizes the current application of human induced pluripotent stem cells and its combination with gene editing technology in the study of inherited ocular diseases. (Chin J Ophthalmol, 2021, 57: 712-716).

[Clinical analysis of left atrial appendage occlusion for stroke prevention in elderly patients with atrial fibrillation]

To evaluate the efficacy and safety of left atrial appendage occlusion (LAAO) in patients with atrial fibrillation (AF) over 75 years. A total of 82 patients with AF who underwent LAAO successfully in Beijing Anzhen Hospital from March 2014 to March 2019 were divided into two groups according to age: the elderly group (aged>75 years) and the young group (aged ≤75 years). Risk of perioperative complications and incidence of ischemic stroke and major bleeding during follow-up were retrospectively analyzed. The results showed that there were no significant differences in procedure-related ischemic stroke(0 vs.1.6%,P=0.768) and major bleeding (0 vs.1.6%,P=0.768) during perioperative period between the two groups. No complications as death or pericardial tamponade occurred in the two group. During a (25.9±15.9) months period of followed up, ischemic stroke event rate was 3.6/100 person-years in the elderly group and 4.9/100 person-years in the young group, respectively. Major bleeding event rate was 2.5/100 person-years in the elderly group and 0/100 person-years in the young group, respectively. Compared with the expected ones, the relative risk reduction (RRR) of stroke in the elderly group was more profound than that in the young group (32.0% vs. 25.0%), while the risk of major bleeding in the young group was significantly lower than that in the elderly group (RRR 100% vs. 56.9%). Therefore, LAAO might be suitable for stroke prevention in the elderly AF patients.

[The impact of digoxin on the long-term outcomes in patients with coronary artery disease and atrial fibrillation]

Objective: To investigate the long-term safety of digoxin in patients with coronary artery disease (CAD) and atrial fibrillation (AF). Methods: This was a prospective study, in which 25 512 AF patients were enrolled from China Atrial Fibrillation Registry Study. After exclusion of patients receiving ablation therapy at the enrollment, 1 810 CAD patients [age: (71.5±9.3)years] with AF were included. The subjects were grouped into the digoxin group and non-digoxin group, and were followed up for a period of 80 months. Long-term outcomes were compared between the groups and an adjusted Cox regression analysis was applied to evaluate the risk of digoxin on the long-term outcomes. The primary endpoint was all-cause mortality. Results: The patients were followed up for a median period of 3.05 years. After multivariable adjustment, the Cox regression analysis showed that digoxin significantly increased the risk of all-cause mortality (HR=1.28, 95%CI 1.01-1.61, P=0.038), cardiovascular mortality (HR=1.48,95%CI 1.10-2.00,P=0.010), cardiovascular hospitalization (HR=1.67,95%CI 1.35-2.07,P=0.008) and the composite endpoints (HR=2.02,95%CI 1.71-2.38,P<0.001). In the subgroup of patients with heart failure (HF), digoxin was not associated with the risk of all-cause mortality, but was still associated with the increased risk of cardiovascular mortality (HR=1.44,95%CI 1.05-1.98,P=0.025), cardiovascular hospitalization (HR=1.44,95%CI 1.09-1.90,P=0.010) and the composite endpoints (HR=1.37, 95%CI 1.01-1.70, P=0.004). However, in the subgroup of patients without HF, digoxin was only associated with all-cause mortality (HR=2.56,95%CI 1.44-4.54,P=0.001). Conclusion: Digoxin significantly increased the risk of all-cause mortality in CAD patients with AF, especially in patients without HF.

The novel AKT inhibitor afuresertib suppresses human Merkel cell carcinoma MKL-1 cell growth

Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine neoplasm of the skin, which has an exceedingly poor prognosis. The AKT/mammalian target of rapamycin (mTOR) signalling pathway, which plays a pivotal role in the modulation of protein synthesis and cell survival, has been shown to be extremely important for Merkel cell carcinogenesis. In the current study, we found that AKT has important regulatory functions in MCC cells and that inhibition of AKT with the novel ATP-competitive AKT inhibitor, afuresertib, has widespread effects on proliferative pathways. In particular, we found that treatment of MCC cells with afuresertib led to deactivation of mTOR and glycogen synthase kinase 3 pathway proteins while increasing activation of proapoptotic pathways through the upregulation of p16 expression and phosphomodulation of the B-cell lymphoma-2-associated death promoter. Overall, afuresertib treatment led to significant and robust inhibition of MCC cell proliferation, thus raising intriguing questions regarding the potential efficacy of AKT inhibition for the future clinical management of MCC.

Detection of Novel Spotted Fever Group Rickettsiae (Rickettsiales: Rickettsiaceae) in Ticks (Acari: Ixodidae) in Southwestern China

Spotted fever group rickettsiae, mainly maintained and transmitted by ticks, are important etiological agents of (re)emerging zoonotic diseases worldwide. It is of great significance to investigate spotted fever group rickettsiae in ticks in different areas for the prevention and control of rickettsioses. In this study, a total of 305 ticks were collected from wild and domestic animals in Chongqing, Guizhou, Yunnan, and Guangxi provinces of southwestern China during 2017-2019 and examined for the presence of spotted fever group rickettsiae by PCR with primers targeting the partial gltA, ompA, rrs, and htrA genes. Results showed that two spotted fever group rickettsiae species, including the pathogenic Candidatus Rickettsia jingxinensis (Rickettsiales: Rickettsiaceae) and a potential novel species Rickettsia sp. sw (Rickettsiales: Rickettsiaceae), were identified. The Ca. R. jingxinensis sequences were recovered from Rhipicephalus microplus (Ixodida: Ixodidae) and Haemaphysalis longicornis (Ixodida: Ixodidae) ticks and phylogenetically clustered with previous Ca. R. jingxinensis, Ca. R. longicornii (Rickettsiales: Rickettsiaceae), and Rickettsia sp. XY118 (Rickettsiales: Rickettsiaceae) strains. Rickettsia sp. sw was detected in Amblyomma geoemydae (Ixodida: Ixodidae) and Rh. microplus. Interestingly, as far as we know, this was the first report of Rickettsia (Rickettsiales: Rickettsiaceae) in A. geoemydae. Phylogenetic analyses indicated that this potential novel species was closely related to R. aeschlimannii (Rickettsiales: Rickettsiaceae) with gltA and ompA genes and grouped in a cluster composed of R. montanensis (Rickettsiales: Rickettsiaceae), R. raoultii (Rickettsiales: Rickettsiaceae), R. aeschlimannii, R. massiliae (Rickettsiales: Rickettsiaceae), and R. rhipicephali (Rickettsiales: Rickettsiaceae) with htrA, while formed a separate clade with rrs. The pathogenicity of Rickettsia sp. sw should be further confirmed. These results expand the knowledge of the geographical distribution and vector distribution of spotted fever group rickettsiae in China and are useful for assessing the potential public health risk.

[Related factors and interaction on hepatitis C virus infection in patients receiving methadone maintenance treatment in Taiyuan]

Objective: To explore the prevalence of hepatitis C virus (HCV) infection, influence factors and interaction on HCV infection in patients receiving methadone maintenance treatment (MMT) in Taiyuan. Methods: Between April-June 2019, three MMT clinics in Taiyuan were selected to conduct a face-to-face questionnaire survey among MMT patients to collect the information about their socio-demographic characteristics, drug use, MMT, sexual behavior and health status. Software EpiData 3.1 was used for real-time double entry to establish the database. Software SAS 9.4 was used to analyze the data, and χ² test was used for univariate analysis and logistic regression model was used for multivariate and interaction analyses. Results: A total of 903 subjects were surveyed among MMT patients, the male to female ratio of was 7.21∶1(743∶103), and the rate of HCV infection was 12.53% (106/846). After adjusting for the confounding factors, being women (OR=1.936, 95%CI: 1.023-3.662), having sex with drug users (OR=2.073, 95%CI: 1.110-3.871) and injection drug use (OR=7.737, 95%CI: 4.614-12.973) might be the risk factors for HCV infection in patients receiving MMT. The results showed that there were multiplicative interactions among women, having sex with drug user and injection drug use on HCV infection. Conclusions: Being women, having sex with drug user and injection drug use were associated with higher risk for HCV infection in patients receiving MMT in Taiyuan. There were multiplication interactions between being women and having sex with drug user, being female and injection drug use, and having sex with drug use and injection drug use on HCV infection.

Metagenome Sequencing Reveals the Midgut Microbiota Makeup of Culex pipiens quinquefasciatus and Its Possible Relationship With Insecticide Resistance

Midgut microbiota can participate in the detoxification and metabolism processes in insects, but there are few reports on the relationship between midgut microbiota and insecticide resistance in mosquitoes. In this study, we performed metagenomic sequencing on a susceptible strain (SS), a field-collected Hainan strain (HN), and a deltamethrin-resistant strain (RR) of Culex pipiens quinquefasciatus to understand the diversity and functions of their midgut microbiota. The results revealed differences in midgut microbiota among the three strains of Cx. pipiens quinquefasciatus. At the phylum level, Proteobacteria was the most prominent, accounting for nearly 70% of their midgut microbes. At the genus level, Aeromonas made up the highest proportion. In addition, Aeromonas, Morganella, Elizabethkingia, Enterobacter, Cedecea, and Thorsellia showed significant differences between strains. At the species level, Bacillus cereus, Enterobacter cloacae complex sp. 4DZ3-17B2, Streptomyces sp. CNQ329, and some species of Pseudomonas and Wolbachia were more abundant in the two resistant strains. Principal component analysis (PCA) showed that the SS strain had significantly different metagenomic functions than the two deltamethrin-resistant strains (HN and RR strain). The HN and RR strains differed from the SS strain in more than 10 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The analysis of species abundance and functional diversity can provide directions for future studies.

Flavobacterium lotistagni sp. nov. and Flavobacterium celericrescens sp. nov., isolated from freshwater habitats

This study presents taxonomic descriptions of strains CYK-4^T and TWA-26^T isolated from freshwater habitats in Taiwan. Both strains were Gram-stain-negative, strictly aerobic, motile by gliding and rod-shaped. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that both strains belonged to the genus Flavobacterium. Analysis of 16S rRNA gene sequences showed that strains CYK-4^T and TWA-26^T shared 92.7 % sequence similarity and were most closely related to Flavobacterium ovatum W201E^T (95.6 %) and Flavobacterium aquaticum JC164^T (96.7 %), respectively. Both strains shared common chemotaxonomic characteristics comprising MK-6 as the main isoprenoid quinone, iso-C_15 : 0 and iso-C_15 : 1 G as the predominant fatty acids, phosphatidylethanolamine as the principal polar lipid, and homospermidine as the major polyamine. The DNA G+C contents of strains CYK-4^T and TWA-26^T were 41.5 and 31.8 mol%, respectively. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between these two novel isolates and their closest relatives were below the cut-off values of 95-96, 90 and 70 %, respectively, used for species demarcation. On the basis of phenotypic and genotypic properties and phylogenetic inference, both strains should be classified as novel species within the genus Flavobacterium, for which the names Flavobacterium lotistagni sp. nov. (type strain CYK-4^T=BCRC 81192^T=LMG 31330^T) and Flavobacterium celericrescens sp. nov. (type strain TWA-26^T=BCRC 81200^T=LMG 31333^T) are proposed.

[Effect of electroacupuncture pretreatment on transient receptor potential vanilloid 1(TRPV1)/calcitonin gene-related peptide(CGRP) signal and NF-κB p65 protein expression in rats with acute myocardial ischemia]

OBJECTIVE

To observe the effect of electroacupuncture(EA)pretreatment on transient receptor potential vanilloid 1(TRPV1)/calcitonin gene-related peptide(CGRP)signal and nuclear factor-κB p65 (NF-κB p65) protein expression in myocardial tissue of acute myocardial ischemic injury (AMI) rats, and to investigate the possible mechanism of electroacupuncture pretreatment against AMI.

METHODS

A total of 60 adult male SD rats were randomly divided into blank control, sham operation, model and EA pretreatment groups, 15 rats in each group. The acute myocardial ischemia model was established by ligating the left anterior descending (LAD)branch of the coronary artery in the model group and EA pretreatment group, while threading but no ligating at left anterior descending branch of the coronary artery was applied in the sham operation group. In the EA pretreatment group, bilateral "Neiguan"(PC6) acupoints were selected, with intensity of 2 mA and frequency of 2 Hz/100 Hz, for 20 min, once daily for 7 days before modeling. Electrocardiogram (ECG) was recorded by physiological signal acquisition system, and the ST segment potential offset values of standard Ⅱ lead were analyzed before surgery，30 min and 24 h after operation. The TTC staining was used to observe the percentage of myocardial infarction area. The HE staining was used to observe the pathological changes of myocardial tissue and the degree of inflammatory cell infiltration. And Western blot was used to detect TRPV1/CGRP signal and NF-κB p65 protein expression levels in myocardial tissue.

RESULTS

Compared with the sham operation group, the ECG-J point potential in the model group was significantly increased at 30 min and decreased at 24 h after operation (P<0.05), myocardial infarction area increased significantly (P<0.05), the myocardial fibers were obviously disordered, inflammatory cell infiltration was obvious, and the expressions of TRPV1，CGRP and NF-κB p65 proteins were all increased (P<0.05). Compared with the model group, the EA pretreatment group was decreased in the ECG-J point potential at 30 min after operation(P<0.05), significantly reduced in myocardial infarction area (P<0.05), improved in the morphology of myocardial fibers, reduced ininflammatory cell infiltration, and increased in the protein expressions of TRPV1 and CGRP in myocardium (P<0.05), significantly decreased in the protein expression of NF-κB p65 (P<0.05).

CONCLUSION

EA pretreatment may enhance TRPV1/CGRP signaling, down-regulate NF-κB p65 protein expression, reduce myocardial inflammatory response status, improve AMI injury, and reduce myocardial infarction area.

Carcinogenesis of Male Oral Submucous Fibrosis Alters Salivary Microbiomes

Most oral squamous cell carcinoma (OSCC) tumors arise from oral premalignant lesions. Oral submucous fibrosis (OSF), usually occurring in male chewers of betel quid, is a premalignant stromal disease characterized by a high malignant transformation rate and high prevalence. Although a relationship between the inhabited microbiome and carcinogenesis has been proposed, no detailed information regarding the oral microbiome of patients with OSF exists; the changes of the salivary microbiome during cancer formation remain unclear. This study compared the salivary microbiomes of male patients with OSCC and a predisposing OSF background (OSCC-OSF group) and those with OSF only (OSF group). The results of high-throughput sequencing of the bacterial 16S rRNA gene indicated that OSF-related carcinogenesis and smoking status significantly contributed to phylogenetic composition variations in the salivary microbiome, leading to considerable reductions in species richness and phylogenetic diversity. The microbiome profile of OSF-related malignancy was associated with increased microbial stochastic fluctuation, which dominated the salivary microbiome assembly and caused species co-occurrence network collapse. Artificial intelligence selection algorithms consistently identified 5 key species in the OSCC-OSF group: Porphyromonas catoniae, Prevotella multisaccharivorax, Prevotella sp. HMT-300, Mitsuokella sp. HMT-131, and Treponema sp. HMT-927. Robust accuracy in predicting oral carcinogenesis was obtained with our exploratory and validation data sets. In functional analysis, the microbiome of the OSCC-OSF group had greater potential for S-adenosyl-l-methionine and norspermidine synthesis but lower potential for l-ornithine and pyrimidine deoxyribonucleotide synthesis and formaldehyde metabolism. These findings indicated that the salivary microbiome plays important roles in modulating microbial metabolites during oral carcinogenesis. In conclusion, our results provided new insights into salivary microbiome alterations during the malignant transformation of OSF.

Efficacy of intrauterine perfusion of peripheral blood mononuclear cells (PBMC) for infertile women before embryo transfer: meta-analysis

This meta-analysis was intended to evaluate the effects of intrauterine perfusion of peripheral blood mononuclear cells (PBMC) on the pregnancy outcomes including clinical pregnancy rates, embryo implantation rates, live birth rates and miscarriage rates of infertile women who were undergoing in vitro fertilisation (IVF) treatment. By searching Pubmed, Embase database, five articles meeting the inclusion criteria were included, and 1173 women were enrolled (intrauterine PBMC group: n = 514; NO-PBMC group: n = 659). For the entire IVF/ICSI population and one or two embryo transfer failure patients, there was no significant difference in endometrial thickness, embryo implantation rates, live birth rates, and miscarriage rates between the PBMC group and NO-PBMC group. Although the clinical pregnancy rates of the PBMC group were higher than that of the NO-PBMC group, the confidence interval was close to the line of unity. As for the patients with three or more implantation failures, the clinical pregnancy rates, embryo implantation rates and live birth rates were much higher in the PBMC group than that of the NO-PBMC group. In summary, current evidence suggests that intrauterine perfusion of PBMC can significantly improve pregnancy outcomes in patients who have three or more implantation failures.Impact statementWhat is already known on this subject? An increasing number of studies have shown that immune cells play an important role in embryo transfer. There is no reliable evidence to confirm the clinical efficacy of intrauterine perfusion of PBMC.What do the results of this study add? The current evidence suggests that intrauterine perfusion of PBMC can significantly improve pregnancy outcomes in patients who have three or more implantation failures.What are the implications of these findings for clinical practice and/or further research? To the best of our knowledge, this meta-analysis is the first to evaluate the effect of intrauterine perfusion of PBMC on pregnancy outcomes before embryo transfer. Our study indicated that intrauterine perfusion of PBMC significantly increased clinical pregnancy rates, embryo implantation rates, and live birth rates in patients who failed more than three implants.

[The thromboembolism risk of low-risk atrial fibrillation patients with different clinical characteristics]

Objective: This study explored the thromboembolism risk of low-risk atrial fibrillation (AF) patients (CHA₂DS₂-VASc score of 0 or 1 for male and 1 or 2 for female) with different clinical characteristics to provide the basis for anticoagulation decision-making in these patients. Methods: We prospectively enrolled consecutive 2 862 nonvalvular low-risk AF patients between August 2011 to December 2018 in China-AF (China Atrial Fibrillation Registry) Study, their CHA₂DS₂-VASc score was 0 or 1 for male and 1 or 2 for female. According to their age, sex, presence or absence of hypertension, diabetes mellitus, congestive heart failure, and vascular disease at the time of enrolling, patients were divided into CHA₂DS₂-VASc score 0 score group, 1 score group, and 2 score group. Patients were followed up every 6 months by outpatient clinic visit or telephone interview. The outcome was a thromboembolic event, including ischemic stroke and systemic embolism. Univariate Cox regression analysis was used to compare the thromboembolism risk between the patients with different risk factors and CHA₂DS₂-VASc score 0 group. Results: A total of 2 862 low-risk atrial fibrillation patients were enrolled in this study. 915 patients (32.0%) were female, and age was (55.0±10.7) years old. There were 933 patients (32.6%) in CHA₂DS₂-VASc score 0 group, 1 401 patients (49.0%) in score 1 group and 528 patients (18.5%) in score 2 group. During follow-up (median 1.5 years, 5 811.82 person-years), 33 cases of thromboembolic events were recorded, the annual rate of thromboembolism was 0.57% (95%CI 0.40%~0.80%). The number of thromboembolic events in patients with CHA₂DS₂-VASc score 0, 1 and 2 were 8, 11 and 14, respectively, and the annual thromboembolism event rates were 0.40% (95%CI 0.20%-0.81%), 0.39% (95%CI 0.22%-0.71%) and 1.34% (95%CI 0.80%-2.27%), respectively. The risk of thromboembolism of CHA₂DS₂-VASc score 2 group (HR=3.53, 95%CI 1.48-8.44; P=0.005), especially female patients aged 65-74 years in CHA₂DS₂-VASc score 2 group (HR=2.67, 95%CI 1.63-4.38; P<0.000) was significantly higher than that in patients of CHA₂DS₂-VASc score 0 group. Conclusion: Low-Risk Atrial Fibrillation patients with CHA₂DS₂-VASc score 2, especially female patients aged 65-74 years old with CHA₂DS₂-VASc score 2 are at higher risk of thromboembolism in low-risk AF patients. For such patients, intensified oral anticoagulant therapy might be helpful to reduce the risk of thrombolism.

[Association between occupational stress and carotid atherosclerosis among the workers in a steel plant]

Objective: To investigate the association between occupational stress and carotid atherosclerosis among the workers in a steel plant. Methods: In October 2018, a total of 2947 workers from a steel plant, who underwent occupational health examination in the center for occupational health examination from March to May 2017, were selected as subjects. Job Content Questionnaire (JCQ) and Effort-Reward Imbalance (ERI) were used to investigate the job content and the degree of occupational stress. According to the results of carotid artery examination, the subjects were divided into normal carotid artery group with 2013 workers, increased carotid intima-media thickness (IMT) group with 277 workers, stable plaque group with 236 workers, and unstable plaque group with 421 workers. A unified questionnaire was distributed to each group, and related physical and biochemical examinations were performed. A multivariate unconditional logistic regression analysis was performed to investigate the risk factors for unstable plaque. Results: There were significant differences between the groups in sex, educational level, marital status, work in shifts, smoking, drinking, age, and working years (P<0.05) , while there was no significant difference in exercise between groups (P>0.05) . Based on the JCQ score, 761 (25.8%) had no stress, 959 (32.5%) had mild stress, 699 (23.7%) had moderate stress, and 528 (17.9%) had severe stress; based on the ERI score, 2526 (85.7%) had high effort and low reward and 421 (14.3%) did not have the high-effort and low-reward conditions. There was a significant difference in the composition of JCQ and ERI scores between groups (P<0.05) . Moderate stress (odds ratio [OR]=1.695) , severe stress (OR=5.443) , ERI (OR=7.391) , work in shift (OR=1.784) , old age (OR=1.009) , high systolic blood pressure (OR=1.105) , high fasting blood glucose (OR=1.212) , abnormal total cholesterol (OR=3.693) , abnormal apolipoprotein B (OR=39.215) , and abnormal high-sensitivity C-reactive protein (OR=1.632) were the risk factors for unstable plaque. Conclusion: Occupational stress may be involved in the development of carotid atherosclerosis.

Proteomic and metabolomic characterization of cardiac tissue in acute myocardial ischemia injury rats

The pathological process and mechanism of myocardial ischemia (MI) is very complicated, and remains unclear. An integrated proteomic-metabolomics analysis was applied to comprehensively understand the pathological changes and mechanism of MI. Male Sprague-Dawley rats were randomly divided into a mock surgery (MS) group and an MI group. The MI model was made by ligating the left anterior descending coronary artery, twenty-four hours after which, echocardiography was employed to assess left ventricular (LV) function variables. Blood samples and left ventricular tissues were collected for ELISA, metabolomics and proteomics analysis. The results showed that LV function, including ejection fraction (EF) and fractional shortening (FS), was significantly reduced and the level of cTnT in the serum increased after MI. iTRAQ proteomics showed that a total of 169 proteins were altered including 52 and 117 proteins with increased and decreased expression, respectively, which were mainly involved in the following activities: complement and coagulation cascades, tight junction, regulation of actin cytoskeleton, MAPK signaling pathway, endocytosis, NOD-like receptor signaling pathway, as well as phagosome coupled with vitamin digestion and absorption. Altered metabolomic profiling of this transition was mostly enriched in pathways including ABC transporters, glycerophospholipid metabolism, protein digestion and absorption and aminoacyl-tRNA biosynthesis. The integrated metabolomics and proteomics analysis indicated that myocardial injury after MI is closely related to several metabolic pathways, especially energy metabolism, amino acid metabolism, vascular smooth muscle contraction, gap junction and neuroactive ligand-receptor interaction. These findings may contribute to understanding the mechanism of MI and have implication for new therapeutic targets.

[Plasmodium falciparum infection complicated by bronchopneumonia in a peacekeeper: a case report]

Malaria is an acute febrile illness caused by Plasmodium. In Africa where the burden of malaria is extremely high, febrile symptoms caused by respiratory tract infections may challenge the diagnosis of malaria, and patients with unclear diagnosis and administration of antimalarial drugs require more attention. Hereby, a peacekeeper with Plasmodium falciparum infection complicated with bronchopneumonia was reported.

[Role of narrow band imaging in the diagnosis of premalignant and malignant lesions of oral cavity]

Objective: To investigate the role of narrow band imaging (NBI) endoscopy in diagnosing oral premalignant and malignant lesions. Methods: NBI and white light (WLI) endoscopy were performed on 85 patients (47 females, 38 males, aged from 12 to 83 years old, the medium age was 58 years) with 144 oral lesions from July 2016 to October 2017 in the First Affiliated Hospital of Xiamen University. NBI findings were classified into 5 types according to the Ni's classification and compared with histopathological results. Sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of NBI and WLI were calculated. Accuracy of NBI on premalignant and malignant lesions were compared with that of WLI. The connection between NBI findings and pathological results were investigated. SPSS 22.0 software was used to analyze the data. Results: Sensitivity, specificity, PPV, and NPV of NBI vs WLI were 96.5% vs 81.2%, 98.3% vs 98.3%, 98.8% vs 98.6%, and 95.1% vs 78.4%, respectively. NBI findings showed high accordance with the phathological results (kappa=0.943,P<0.01). However, consistency between WLI findings and the phathological results was relatively low (kappa=0.765, P<0.01). NBI was more accurate in diagnosing both premalignant (P<0.01) and malignant lesions (especially for high-grade intraepithelial neoplasia, P<0.01) than WLI. There was remarkable correlation between NBI findings and the phathological results (r=0.836, P<0.01). Conclusions: NBI shows high accuracy in detecting premalignant and malignant lesions of oral cavity. Ni's NBI classification is helpful to diagnose the premalignant and early malignant lesions as well as to evaluate tumor invasion. Thus, NBI can contribute more to early diagnosis and therapy of premalignant and malignant lesions of oral cavity.