[Role of Dipeptidyl peptidase inhibitors in lung ischemia-reperfusion injury]

Lung ischemia-reperfusion injury (LIRI)is a common complication after lung transplantation and cardiopulmonary bypass. It is an important factor affecting the success rate of transplantation. Its specific pathogenesis has not yet been fully elucidated. It is very significant to find the targets and drugs for the prevention and treatment of LIRI in order to improving the utilization rate of "marginal donor lung" and the long-term survival rate of lung transplant patients. Dipeptidyl peptidase 4(DPP4) inhibitors are a class of oral hypoglycemic agents. Previous studies have shown that DPP4 inhibitors have a variety of pharmacological activities, including anti-inflammatory, anti-fibrotic, immunomodulatory and other extrapancreatic functions. Recent studies have shown that DPP4 inhibitors may alleviate LIRI through various mechanisms, including inhibiting inflammatory responses, reducing oxidative stress, regulating blood glucose levels, and activating autophagy. This article reviewed the clinical and preclinical applications and mechanisms of DPP4 inhibitors in LIRI.

[The versions of Shiguzhai Hui Ju Jian Bian Dan Fang by Wu Mianxue]

Shiguzhai Hui Ju Jian Bian Dan Fang, was the only medical book for prescription and formula collected and compiled by Wu Mianxue in the period of the Wanli in the Ming Dynasty (1573-1620). It had seven volumes in total with six of them popular at that time. The volumes contained 1,460 folk formula and clinical prescriptions which were divided into 111 categories based on their corresponding symptoms of diseases. The set was issued in the beginning of the 17^th century, with only three subsets of the volumes left in China today. The three remained versions were the subset of volumes 4-5 left in the Ming Dynasty in the Medical College of Tianjin, the subset of volumes 1-2 and 6-7, with preface, left in the seventeenth of the Shun Zhi Period in the Qing Dynasty (1660) in the Shanghai University of Chinese Medicine and the subset of volumes 4 and 6-7 from time unknown. Additionally, three unabridged versions were found in the Cabinet Library of the National Archives of Japan. They were the Ming version with preface of the seventeenth of the Shun Zhi Period in the Qing Dynasty and a hand-copied version left in the Edo period. It was found that the preface in the seventeenth of the Shun Zhi Period in the Qing Dynasty in both of these versions in China as well as the version in Japan, were counterfeit. The main texts in these versions were edited according to the Ming version. The hand-copied version in Japan was transcribed by Kasahara Eisan and edited by Tanba Motoken according to the Ming version in the late Edo Period.

Bioinspired Anti-demineralization Enamel Coating for Orthodontics

White spot lesions and enamel cracks are the 2 most prominent diseases that occur after orthodontic treatment and are caused by enamel demineralization from accumulated bacterial biofilms and/or enamel damage caused by the removal of residual adhesive after bracket debonding. Inspired by the self-assembled amelogenin nanoribbons in enamel, we developed an enamel coating with a self-assembling antimicrobial peptide, D-GL13K, to simultaneously reduce demineralization and residual adhesive. The self-assembled amphiphilic nanoribbons significantly increased the hydrophobicity of the etched enamel, which reduced the permeability of the coated enamel surfaces as desired. The antimicrobial activity of this coating was evaluated against Streptococcus mutans by colony-forming unit counting and live/dead assays. The anti-demineralization effect was demonstrated by the reduced demineralization depth analyzed by optical coherence tomography and the increased Vickers hardness. The coatings did not reduce the shear bond strength but significantly reduced the adhesive remnant index score. This bioinspired enamel coating may provide a new strategy for preventing white spot lesions and enamel cracks after orthodontic treatment.

[Role of brain and muscle ARNT-like protein 1 in the rat periodontitis-induced liver injury model]

Objective: Brain and muscle ARNT-like protein 1 (BMAL1) is a core component of hepatocyte molecular clock and plays an important role in the regulation of other related rhythmic genes in the body through a transcriptional-translational feedback loop in molecular circadian oscillations. Therefore, the aim of this study was to investigate the role of BMAL1 in the rat periodontitis-induced liver injury. Methods: Twelve male Wistar rats were divided into the control group and the periodontitis group according to the random number table method. The rats in the control group were untreated. The periodontitis models were established by ligating the necks of the bilateral maxillary first molars in the periodontitis group rats. After 8 weeks, periodontal clinical indexes of rats in both groups were examined and executed. Micro-CT scans of the maxilla were performed and levels of the alveolar bone resorption were analyzed. Pathological changes in periodontal and liver tissue of rats in two groups were detected by HE and oil red O staining. Biochemical kits were used to detect glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT), total cholesterol (TC) and triglycerides (TG) in serum. The gene and protein expression levels of BMAL1, nuclear factor kappa-B (NF-κB) and tumor necrosis factor-α (TNF-α) in liver tissue were measured by real time fluorescent quantitative-PCR (qRT-PCR), immunohistochemistry (IHC) and Western blotting (WB) assays. Apoptosis was detected in liver tissues by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) kit staining. Results: The results of HE staining of maxillary first molars and micro-CT results of maxillary bones showed that alveolar bone resorption was significant in the periodontitis group of rats. The liver histopathology results showed infiltrated inflammatory cells in the liver tissue, disorganized liver cords and a large number of lipid droplets formed in the hepatocytes of the periodontitis group compared with the control group. The results of serum biochemical assay showed that the levels of GOT [(62.77±2.59) U/L], GPT [(47.54±1.04) U/L], TC [(3.19±0.23) mmol/L] and TG [(1.11±0.09) mmol/L] in the serum of rats with periodontitis were significantly higher than that in the control group respectively [GOT: (38.66±2.47) U/L, GPT: (31.48±1.57) U/L, TC: (1.60±0.05) mmol/L and TG: (0.61±0.09) mmol/L](P=0.003, P=0.001, P=0.002, P=0.038). qRT-PCR results showed that the mRNA expression level of BMAL1 was significantly decreased in liver tissue of the periodontitis group [(0.60±0.04)%] compared to the control group [(1.01±0.07)%] (t=4.80, P=0.009), while the mRNA expression levels of NF-κB and TNF-α [(1.62±0.12)%, (2.69±0.16)%] were significantly increased compared to the control group [(1.00±0.03)%, (1.03±0.16)%] (P=0.008, P=0.002); IHC results showed that the protein expression level of BMAL1 in liver tissue of the periodontitis group (averaged optical density, AOD) (11.58±2.15) was down-regulated compared to the control group (AOD) (22.66±1.67) (P=0.015), while NF-κB and TNF-α (AOD) (31.77±2.69, 24.31±2.32) were up-regulated compared to the control group (AOD) (19.40±1.82, 11.92±0.94) (P=0.019, P=0.008). WB results showed that the protein expression level of BMAL1 in liver tissue was down-regulated in the periodontitis group [(0.63±0.10)%] compared to the control group [(1.00±0.06)%] (t=3.19, P=0.033), while NF-κB and TNF-α [(1.61±0.12)%, (2.82±0.23)%] were up-regulated compared to the control group [(1.00±0.12)%, (1.00±0.11)%] (P=0.022, P=0.002). TUNEL staining showed increased apoptotic cells in the liver tissue of the periodontitis group of rats compared to the control group. Conclusions: Periodontitis may induce liver injury by down-regulating the BMAL1 expression levels in liver tissue, which in turn activates NF-κB signaling molecules, leading to the elevated levels of inflammation and apoptosis in rat liver.

[Epidemic trend and control progress of taeniasis and cysticercosis in Henan Province]

Henan Province is one of the provinces where taeniasis and cysticercosis were historically highly prevalent, and Taenia solium is the dominant species of tapeworm. Following the concerted efforts since 1970s, the prevalence of human taeniasis and cysticercosis has been maintained at a low level in Henan Province, which facilitates the national taeniasis and cysticercosis elimination program in China. Following the implementation of the policy of aeniasis and cysticercosis elimination and classified guidance, a great success has been achieved in aeniasis and cysticercosis control in Henan Province. With continuous promotion of the opening-up policy and the Belt and Road Initiative, there are still challenges in taeniasis and cysticercosis control. This review summarizes the control progress of taeniasis and cysticercosis and proposes the challenges of taeniasis and cysticercosis control in Henan Province.

[Prevalence and risk factors of Giardia lamblia infections among colorectal cancer patients in Henan Province]

OBJECTIVE

To investigate the epidemiological characteristics and identify the risk factors of Giardia lamblia infections among patients with colorectal cancer in Henan Province.

METHODS

A cross-sectional study was performed for questionnaire surveys among colorectal cancer patients in Henan Cancer Hospital during the period from March to July, 2021. Patients' stool samples were collected, and the triosephosphate isomerase (tpi) gene of G. lamblia was amplified in stool samples using nested PCR assay to characterize the parasite genotype. Univariate analysis and multivariate logistic regression analyses were employed to identify the risk factors of G. lamblia infections among colorectal cancer patients.

RESULTS

A total of 307 colorectal cancer patients were investigated, including 176 males (57.3%) and 131 females (42.7%). PCR assay detected 8.1% [95% confidential interval (CI): (0.056, 0.117)] prevalence of G. lamblia infections among the study subjects, and there was no significant difference in the prevalence between men [9.1%, 95% CI: (0.057, 0.143)] and women [6.9%, 95% CI: (0.037, 0.125)] (χ² = 0.495, P = 0.482). In addition, there was no age-specific prevalence of G. lamblia infections among the participants (χ² = 1.534, P = 0.675). Multivariate logistic regression analysis identified use of septic tanks [odds ratio (OR) = 3.336, 95% CI: (1.201, 9.267)], daily use of well water [OR = 3.042, 95% CI: (1.093, 8.465)] and raising livestock [OR = 3.740, 95% CI: (1.154, 12.121)] as risk factors of G. lamblia infections among colorectal cancer patients, and the prevalence of abdominal pain was significantly greater in colorectal cancer patients with G. lamblia infections than in those without infections (P = 0.017). Among the 25 patients with G. lamblia infections, assemblage A was characterized in 24 (96.0%) cases and assemblage B in one case (4.0%).

CONCLUSIONS

The prevalence of G. lamblia is high among colorectal cancer patients in Henan Province, and assemblage A is the dominant genotype of G. lamblia. Use of septic tanks, daily use of well water and raising livestock are risk factors of G. lamblia infections among patients with colorectal cancer.

Fn1 Regulates the Third Pharyngeal Pouch Patterning and Morphogenesis

The parathyroid and thymus are derived from the common primordia, the third pharyngeal pouch. During their development, endodermal cells actively interact with surrounding mesenchymal cells, mainly derived from neural crest cells (NCCs). However, the mechanism by which NCCs regulate the development of the third pharyngeal pouch remains largely unknown. In this study, we showed that fibronectin 1 (Fn1), which is synthesized by NCCs, modulates the functions of NCCs in the third pharyngeal pouch patterning and in the morphogenesis of the thymus/parathyroid. Loss of Fn1 in NCCs leads to decreased Foxn1 expression in the presumptive thymus domain at E11.5. In the mutant, we detected upregulation of the Hedgehog signaling activity in the presumptive parathyroid domain and downregulation of Bmp4 in the presumptive thymus domain. Tbx1, a Hedgehog signaling target gene in endoderm development, was ectopically expanded to the presumptive mutant thymus domain at E11.5. Fgf10, an important gene regulating the proliferation of endoderm development, was downregulated in the mutant NCCs. At later organogenesis stages, derivatives of the third pharyngeal pouch endoderm of mutant embryos were abnormal, showing conditions such as hypoparathyroidism, hypoplastic thymus, and ectopic thymus and parathyroid. These data support that Fn1 plays an important role in NCCs by regulating the patterning of the third pharyngeal pouch and morphogenesis of the thymus/parathyroid.

[Impact of Streptococcus pneumoniae colonization in upper airway on the clinical manifestations of children with respiratory syncytial virus infection]

Objective: To investigate the effects of Streptococcus pneumoniae (Spn) colonization and the change of upper airway microbiome on the clinical manifestations in children with respiratory syncytial virus (RSV) infection. Methods: A retrospective cohort included 508 RSV-infected children with pneumonia and hospitalized in Respiratory Department of Children's Hospital of Chongqing Medical University from July 2009 to July 2018. A total of 508 cases of RSV-infected children (RSV non-sequencing group) were divided into 2 groups: children with Spn airway colonization (RSV+Spn group) and children without with Spn airway colonization (RSV group) according to the detection for virus and bacteria in nasopharyngeal aspirate, and these 2 groups were compared in terms of clinical manifestations by chi-square test in different age groups. In addition, in RSV pandemic season from November 2018 to February 2020, nasopharyngeal aspirates were collected from 20 children hospitalized in Respiratory Department of Children's Hospital of Chongqing Medical University and infected with RSV but without any positive detection of bacteria (RSV 16 S-sequencing group) and from children undergoing surgery without any sign of respiratory infection (control group). The difference of microbiome detected by 16 S RNA sequencing was compared using rank sum test between RSV 16 S-sequencing group and control group, and also between children with severe and mild pneumonia in RSV 16 S-sequencing group. Results: A total of 508 RSV non-sequencing group included 346 males and 162 females, and the visiting age was 6 (2, 12)  months. RSV group included 443 cases and RSV+Spn group included 65 cases. In the study 244 cases were aged <6 months and 264 cases were aged ≥6 months. In children aged ≥6 months of RSV non-sequencing group, the proportion of cases presenting fever over 38 ℃ and cases with severe pneumonia in RSV+Spn group were higher than those in RSV group (53.2% (25/47) vs. 34.6% (72/217), 38.3% (18/47) vs. 21.2% (46/217), χ²=5.70,6.15, both P<0.05). RSV 16 S-sequencing group included 16 males and 4 females and the visiting age was 3.0 (1.9, 8.0) months. Airway microbiome diversity in RSV 16 S-sequencing group was lower than that in control group (alpha index: 0.93 (0.42, 2.51) vs. 3.05 (2.88, 3.61), U=60.00, P=0.001). Conclusions: RSV infection is associated with the changes of the upper airway microbiome. When the balance of airway microbiome is broken and the presence of the dominant colonization of Spn follows, it may aggravate the severity of RSV infection in children aged ≥6 months.

Menopausal hormone therapy: what are the problems in the perception of Chinese physicians?

OBJECTIVE

This study aimed to investigate Chinese physicians' perception and attitudes toward menopausal hormone therapy (MHT).

METHODS

This nationwide online survey was conducted in China. Physicians registered in the WeChat groups of the Gynecological Endocrinology Committee of China's Maternal and Child Health Care Association received a message invitation to complete this anonymous online survey from April 2020 to July 2020. Physicians' knowledge of and attitudes toward MHT were surveyed.

RESULTS

In total, 4672 questionnaires were submitted; only completed questionnaires could be submitted. The message was sent to 6021 doctors, so the response rate was 77.6%. Overall, 77.9-92.9% of physicians knew the common indications and contraindications to MHT. Additionally, 90.6%, 85.4%, 80.7% and 37.5% of physicians thought that MHT would increase the risk of venous thrombosis, breast cancer, endometrial cancer and weight gain, respectively. In total, 58.1% of the physicians mistakenly believed that a sex hormone test was one of the necessary examinations to reassess MHT prescription during follow-up visits. We found that 68.5% of physicians would consider using MHT themselves or recommend MHT to their partners in the future, and 11.4% were currently using MHT.

CONCLUSIONS

Most Chinese physicians have basic knowledge of MHT. Their misunderstandings about MHT mainly centered on the risks of endometrial cancer, weight gain and the necessary examinations during follow-up visits. These misunderstandings need to be clarified in future professional training programs.

[Progress in the practice of surveillance and early warning of infectious diseases in major countries and regions]

The COVID-19 pandemic is yet another reminder that the threat of infectious disease has never really gone away. As the cornerstone of preventing and controlling infectious diseases, effective surveillance and early warning are of great significance in understanding the outbreak and epidemic of specific infectious diseases and putting forward effective prevention and control measures. Therefore, we must continue strengthening the construction of infectious disease surveillance and early warning system. We reviewed the surveillance and early warning practices of infectious diseases in major countries and regions, then discussed the development direction in the field of surveillance and early warning of infectious diseases to provide the reference for strengthening the construction and capacity of infectious disease surveillance and early warning system in China.

[Evaluation of efficiency of different anti-cysticercus antibody test kits for serodiagnosis of cysticercosis]

OBJECTIVE

To evaluate the diagnostic efficiency of four anti-cysticercus IgG, IgG4 or IgM antibody test kits (enzyme-linked immunosorbent assay, ELISA) by different manufacturers, so as to provide insights into the epidemiological investigation and clinical detection of cysticercosis.

METHODS

Forty serum samples from cerebral cysticercosis patients, 100 serum samples from healthy volunteers, 30 serum samples from paragonimiasis skrjabini patients, 17 serum samples from cystic echinococcosis and 19 serum samples from subcutaneous or cerebral sparganosis patients were collected and detected using anti-cysticercus IgG, IgG4 or IgM antibody test kits (brand A) and the anti-cysticercus IgG antibody test kit (brand B). The sensitivity, specificity and false negative rate of the four kits for detection of cysticercosis were estimated.

RESULTS

The anti-cysticercus IgG, IgG4 or IgM antibody test kits (brand A) showed 95.00% (38/40), 87.50% (35/40), 7.50% (3/40) sensitivities and 98.00% (98/100), 100.00% (100/100) and 100.00% (100/100) for detection of cysticercosis, while the anti-cysticercus IgG antibody test kit (brand B) presented a 75.00% (30/40) sensitivity and 100.00% (100/100) specificity for detection of cysticercosis. The sensitivity for detection of cysticercosis was significantly higher by the anti-cysticercus IgG antibody test kit (brand A) than by the anti-cysticercus IgG antibody test kit (brand B) (χ² = 6.28, P < 0.05); however, no significant difference was seen in the specificity by two kits (χ² = 2.01, P > 0.05). The four ELISA kits showed overall false positive rates of 37.88% (25/66), 22.73% (15/66), 62.12% (41/66) and 15.15% (10/66) for detection of paragonimiasis, echinococcosis and sparganosis (χ² = 37.61, P < 0.05), and the anti-cysticercus IgG antibody test kit (brand A) presented the highest overall false positive rate for detection of paragonimiasis, echinococcosis and sparganosis (χ² = 7.56, P' < 0.008), while a higher overall false positive rate was seen for detection of paragonimiasis, echinococcosis and sparganosis by the anti-cysticercus IgG antibody test kit (brand A) than by the anti-cysticercus IgG antibody test kit (brand B) (χ² = 8.75, P' < 0.008). The four ELISA kits showed false positive rates of 40.00% (12/30), 16.67% (5/30), 76.67% (23/30) and 13.33% (4/30) for detection of paragonimiasis (χ2 = 32.88, P < 0.05) and 21.05% (4/19), 26.32% (5/19), 73.68% (14/19) and 15.79% (3/19) for detection of sparganosis (χ² = 19.97, P < 0.05), and the highest false positive rates were found by the anti-cysticercus IgM antibody test kit (brand A) for detection of paragonimiasis and sparganosis (all P' < 0.008). However, the four ELISA kits showed comparable false positive rates of 52.94% (9/17), 29.41% (5/17), 23.53% (4/17) and 17.65% (3/17) for detection of echinococcosis (χ² = 8.24, P > 0.05). In addition, the anti-cysticercus IgM anti-body test kit (brand A) showed false positive rates of 76.67% (23/30), 23.53% (4/17) and 73.68% (14/19) for detection of paragonimiasis, echinococcosis and sparganosis (χ² = 14.537, P < 0.05), with the lowest false positive rate seen for detection of echinococcosis (χ² = 14.537, P' < 0.014), while no significant differences were seen in the false positive rate for detection of paragonimiasis, echinococcosis and sparganosis by other three ELISA kits (all P > 0.05).

CONCLUSIONS

The four anti-cysticercus IgG, IgG4 or IgM antibody test kits exhibit various efficiencies for serodiagnosis of cysticercosis. The anti-cysticercus IgG antibody test kit (brand A) has a high sensitivity for serodiagnosis of cysticercosis; however, it still needs to solve the problems of cross-reaction with other parasitic diseases and stability.

[Analysis of lactate dehydrogenase gene polymorphisms and prediction of B cell epitopes in four human Plasmodium species]

OBJECTIVE

To analyze the polymorphism of Plasmodium lactate dehydrogenase (pLDH) gene and predict B-cell epitopes in pLDH peptides in four species of human malaria parasites.

METHODS

The blood samples and epidemiological characteristics were collected from malaria cases in Yunnan Province registered in the National Notifiable Disease Report System. The pLDH genes of four human Plasmodium species were amplified using nested PCR assay and sequenced. The polymorphisms of pLDH genes was analyzed using the software MEGA version 7.0.26 and DnaSP version 5.10, and the B-cell epitopes were predicted in pLDH peptides using the Immune Epitope Database (IEDB).

RESULTS

The sequences of P. vivax LDH (PvLDH), P. falciparum LDH (PfLDH), P. ovale LDH (PoLDH) and P. malariae LDH (PmLDH) genes were obtained from 153, 29, 17 and 11 blood samples from patients with P. vivax, P. falciparum, P. ovale and P. malariae malaria, respectively, which included 15, 2, 4 and 2 haplotypes and had a nucleotide diversity (π) of 0.104. A high level of intra-species differentiation was seen in the PoLDH gene (π = 0.012), and the π values were all < 0.001 for PvLDH, PfLDH and PmLDH genes. Active regions of B-cell antigen were predicted in the pLDH peptide chain of four human malaria parasites, of 4 to 5 in each chain, and the activity score was approximately 0.430. Among these peptide chains, the "86-PGKSDKEWNRD-96" short-peptide was a B-cell epitope shared by all four species of human malaria parasites, and the "266-GQYGHS (T)-271" short-peptide was present in PvLDH and PoLDH peptide chains, while "212-EEVEGIFDR-220" was only found in the PvLDH peptide chain, and "208-LISDAE-213" was only seen in the PfLDH peptide chain.

CONCLUSIONS

The PoLDH gene polymorphism may be derived from the weak negative purification selection, while PvLDH, PfLDH and PmLDH genes may maintain a relatively conservative state. There may be two B-cell epitopes "212-EEVEGIFDR-220" and "208-LISDAE-213" in the proximal region of the C terminal in the pLDH peptide chain, which is feasible to differentiate between P. vivax and P. falciparum infections.

Resveratrol protects renal damages induced by periodontitis via preventing mitochondrial dysfunction in rats

OBJECTIVES

Periodontitis is closely associated with kidney disease and reactive oxygen species (ROS) involvement. Mitochondria are the primary source of both endogenous ROS and renal energy. We investigated whether resveratrol (RSV) prevents renal injury and mitochondrial dysfunction in periodontitis rats.

METHODS

Thirty male Wistar rats were divided into control, experimental periodontitis (Ep), and Ep-RSV groups. To induce periodontitis, a steel ligature was placed on the cervix of the bilateral first maxillary molars. RSV (50 mg/kg/d) to the Ep-RSV group and vehicle to the Ep and control groups were gavaged. After 8 weeks, alveolar bone loss, pocket depth, gingival blood index, and tooth mobility were assessed. Oxidative stress parameters, mitochondrial structure, mitochondrial membrane potential (MMP), mitochondrial ROS, adenosine triphosphate (ATP), sirtuin 1 (SIRT1), and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) were analysed in renal. Renal function and histology were also evaluated.

RESULTS

Compared with the control group, the Ep group showed renal structural destruction, elevated oxidative stress levels, mitochondrial structure destruction, MMP loss, mitochondrial ROS accumulation, ATP reduction, and decreased SIRT1 and PGC-1α levels. RSV prevented these destruction (p < .05). However, there was no significant impairment in renal function (p > .05).

CONCLUSIONS

Periodontitis induced mitochondrial dysfunction in renal tissues. Resveratrol exerts a preventive effect on periodontitis-induced kidney injury by preventing mitochondrial dysfunction.

[Immunogenicity and safety of a booster vaccination with an inactivated severe acute respiratory syndrome coronavirus 2 vaccine in adults aged 18 to 59 years]

Objective: To assess the immunogenicity and safety of a booster vaccination with an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine. Methods: The phase Ⅱ trial of an inactivated SARS-CoV-2 vaccine was conducted by Jiangsu Provincial Center for Disease Control and Prevention (CDC) since October 2020. The subjects were healthy adults aged 18-59 years, excluding pregnant, and not breastfeeding women. The primary vaccination schedule groups were 0-14 d 5 μg, 0-14 d 10 μg, 0-28 d 5 μg and 0-28 d 10 μg, respectively. And 50 participants in each group, a total of 200, who have received 2-doses primary vaccination were selected in ascending order of the study number and vaccinated with a booster dose (same dosage as primary vaccination) at the 6th months after post the primary vaccination (30-day window period). Blood samples were collected before and after boosting and tested for the geometric mean titers (GMT) and seroconversion of live virus neutralizing antibody, pseudovirus neutralizing antibody and receptor-binding-domain (RBD) IgG antibody. Adverse events (AE) were collected and assessed within 28 days after boosting. Results: The ages of subjects in group 0-14 d 5 μg, 0-14 d 10 μg, 0-28 d 5 μg and 0-28 d 10 μg were (43.98±9.58), (43.46±9.34), (42.56±9.08) and (43.94±11.05) years old, respectively (P=0.877). Sex ratios were balanced among the 4 groups (P=0.331). The live virus neutralizing antibody GMT (95%CI) in group 0-14 d 5 μg, 0-14 d 10 μg, 0-28 d 5 μg and 0-28 d 10 μg increased from 4.07 (3.30-5.04), 3.75 (3.08-4.55), 8.33 (7.01-11.11) and 7.69 (6.19-9.57) before the booster vaccination to 284.84 (215.28-376.86), 233.05 (178.61-304.08), 274.81 (223.64-337.68) and 280.77 (234.59-336.04) in 28 days after the booster vaccination, respectively. The rates of live virus neutralizing antibody seroconversion were all 100% in the 4 groups. The AE incidences following booster vaccination were 18.0% (9 cases), 4.0% (2 cases), 12% (6 cases), and 12% (6 cases) in the 4 groups(P=0.182). No AE was graded as level 3 or worse. No serious AE was reported. Conclusion: One booster vaccination of an inactivated SARS-CoV-2 vaccine administered 6 months after primary vaccination showed good immunogenicity and safety.

[Effectiveness of training on Taenia solium taeniasis and cysticercosis control knowledge among medical professionals in disease-elimination pilot areas of Henan Province]

OBJECTIVE

To investigate the changes in the awareness rate of Taenia solium taeniasis and cysticercosis control knowledge among medical professionals before and after training in Fangcheng County, a disease-elimination pilot area of Henan Province, so as to evaluate the effectiveness of the training.

METHODS

Three townships in Fangcheng County were randomly selected as the study townships, including Dushu, Bowang and Yangji townships, while Erlangmiao, Yanglou and Xiaoshidian townships in the county were randomly selected as the control townships. The grassroots medical professionals in the study townships were given once training on T. solium taeniasis and cysticercosis control knowledge each year from 2016 to 2020, while those in the control townships were given no interventions. All village-level doctors and a part of township-level public health professionals were sampled from the study and control townships as intervention and control groups. The baseline and final assessments of the awareness of T. solium taeniasis and cysticercosis control knowledge were performed using questionnaire survey in intervention and control groups in 2016 and 2020, and the awareness of T. solium taeniasis and cysticercosis control knowledge was compared between the two groups.

RESULTS

A total of 663 medical professionals were investigated in Fangcheng County from 2016 to 2020, including 474 participants in the intervention group and 189 participants in the control group. Results from the 2016 baseline survey showed that the awareness rate of T. solium taeniasis and cysticercosis control knowledge was 28.83% (47/163) among grassroots medical professionals in Fangcheng County, and there were no significant differences in the awareness between the intervention (32.47%, 25/77) and control groups (25.58%, 22/86) (χ² = 0.939, P > 0.05), between men (30.50%, 43/141) and women (18.18%, 4/22) (χ² = 1.406, P > 0.05) or between village- (31.39%, 43/137) and township-level medical professionals (15.38%, 4/26) (χ² = 2.727, P > 0.05), while significant differences were found in the awareness rate of T. solium taeniasis and cysticercosis control knowledge among medical professionals in terms of education levels (χ² = 8.190, P < 0.05) and duration of working experiences (χ² = 12.617, P < 0.05), and the awareness rate of T. solium taeniasis and cysticercosis control knowledge increased with education levels among medical professionals (χ² = 6.768, P < 0.05). Only 5.52% (9/163) of the medical professionals had a history of diagnosis and therapy of T. solium taeniasis or cysticercosis, and only 1.23% (2/163) received training on T. solium taeniasis and cysticercosis control knowledge during the past 5 years. Results from the 2020 questionnaire survey showed a higher awareness rate of T. solium taeniasis and cysticercosis control knowledge among medical professionals in the intervention group (93.55%, 116/124) than in the control group (46.60%, 48/103) (χ² = 61.845, P < 0.05), and no significant differences were seen in the awareness rate of T. solium taeniasis and cysticercosis control knowledge among medical professionals in terms of gender, level of medical professionals, duration of working experiences or history of diagnosis/therapy of T. solium taeniasis and cysticercosis in the intervention group (χ² = 1.089, 0.140, 0.081 and 0.453, all P values > 0.05), while there was a significant difference in the awareness rate among medical professionals with different education levels (χ² = 36.338, P < 0.05). In addition, the awareness rate of T. solium taeniasis and cysticercosis control knowledge significantly increased among medical professionals with various chracteristics in 2020 than in 2016.

CONCLUSIONS

In the low-prevalence areas of T. solium taeniasis and cysticercosis, long-term and persistent training may improve the awareness of T. solium taeniasis and cysticercosis control knowledge among grassroots medical professionals, which facilitates the timely identification of T. solium taeniasis and cysticercosis and the establishment of a sensitive disease surveillance system.

[Effectiveness of health education interventions targeting taeniasis and cysticercosis among primary school students in disease-elimination pilot areas of Henan Province]

OBJECTIVE

To compare the changes of knowledge, attitude and practice (KAP) related to taeniasis and cysticercosis among primary school students before and after health education interventions in disease-elimination pilot areas of Henan Province, so as to evaluate the effectiveness of health education interventions.

METHODS

A primary school was selected from each of Dushu, Bowang and Yangji townships, Fangcheng County, Henan Province from 2017 to 2019; then, 2 to 3 classes were randomly selected from grade 4 to 6 in each primary school, and finally, all students in these classes were enrolled as study subjects. A thematic health education lecture pertaining to taeniasis and cysticercosis was given once each year by means of "health education in class". The KAP towards taeniasis and cysticercosis was investigated among primary school students using selffilled structured questionnaires, and the changes of awareness of taeniasis and cysticercosis control knowledge and percentage of healthy behaviors formation were compared in primary school students among years and following various frequencies of health education interventions.

RESULTS

More than 10 thousand person-time primary school students received health education interventions during the period from 2017 to 2019, and a total of 1 223 person-time primary school students were investigated during the 3-year study period, including 633 person-time men and 590 person-time women and 88.55% of primary school students at ages of 10 to 12 years. The proportion of households raising pigs and using dry toiliets decreased from 5.30% (24/453) and 18.10% (82/453) in 2017 to 3.60% (13/361) and 11.08% (40/361) in 2019, respectively. The awareness rate of taeniasis and cysticercosis control knowledge increased significantly from 0.22% (1/453) in 2017 to 62.59% (256/409) in 2018 and 76.73% (277/361) in 2019 (χ² = 567.60, P < 0.001), and the awareness rate was 85.25% (104/122) among primary school students attending the thematic special health education courses for successive three times. The awareness rates of taeniasis and cysticercosis control knowledge were 0.44% (1/225), 58.00% (116/200) and 71.63% (149/208) among male students and 0 (0/338), 66.99% (140/209) and 83.66% (128/153) among female students from 2017 to 2019, and there was a significant difference in the awareness of taeniasis and cysticercosis control knowledge between male and female students in 2019 (χ² = 7.14, P = 0.01). On-site teaching by doctors was the students' favorite way to receive health education interventions (70.07%, 857/1 223), followed by watching health education videos (58.63%, 717/1 223) and seeing parasite specimens (48.9%, 598/1 223). The proportion of students' families who used cutting boards for raw and cooked food separately increased from 7.28% (33/453) in 2017 to 47.37% (171/361) in 2019, was 67.21% (82/122) among students attending the health education courses for successive three times. The proportion of students who frequently washed their hands before meals and after using toilet increased from 71.96% (324/453) in 2017 to 89.47% (319/361) in 2019 and was 95.90% (117/122) among students attending the health education courses for successive three times. In addition, the percentage of students washing hands frequently in families using dry toilets was significantly lower in those who did not use dry toilets (χ² = 9.21, P = 0.002), and the proportion of students with a habit of eating raw or undercooked meat decreased significantly from 35.76% (162/453) in 2017 to 6.65% (24/361) in 2019 (χ² = 69.11, P < 0.01).

CONCLUSIONS

The thematic health education activity of "health education in class" contributes greatly to the increase in the awareness of taeniasis and cysticercosis control knowledge and the rate of healthy behaviors formation among primary school students in diseaseelimination pilot areas of Henan Province.

ToxR modulates biofilm formation in fish pathogen Vibrio harveyi

Vibrio harveyi is a common aquaculture pathogen causing diseases in a variety of aquatic animals. toxR, a conserved virulence-associated gene in vibrios, is identified in V. harveyi 345, a pathogenic strain isolated from diseased fish. In this study, to gain insight into function of ToxR in V. harveyi, an in-frame deletion of the toxR gene was constructed to reveal the role of ToxR in the physiology and virulence of V. harveyi. The statistical analysis showed no significant differences in the growth ability, motility, extracellular protease secretion, antibiotic susceptibility, virulence by intraperitoneal injection and the ability of V. harveyi to colonize the spleen and liver tissues of the pearl gentian grouper between the wild-type (WT) and the toxR mutant. However, the deletion of toxR increased the biofilm formation. The structure of the V. harveyi biofilm was further analysed by using scanning electron microscopy (SEM) and confocal laser scanning microscopy, and the results showed that deletion of toxR increased the number and density of V. harveyi biofilm. Since biofilm production is flagella, exopolysaccharide (EPS) and lipopolysaccharide dependent, 16 of V. harveyi biofilm-related genes were selected for further analysis. Based on quantitative real-time reverse transcription-PCR, the expression levels of these genes, including genes flrB, motY and mshA, flaE, flrA and gmhD, were significantly up-regulated in the ΔtoxR⁺ strain as compared with the WT⁺ and C-ΔtoxR strains during the early and mid-exponential, while epsG, flaA, flaE, flgD, flgE, flrB, flrC, lpxB, motY, mshA and scrG genes were inhibited because of deletion of the toxR gene in the stationary growth phase. Our results indicate that ToxR plays an important role in controlling the biofilm in V. harveyi.

[Establishment of a fluorescent recombinase-aided isothermal amplification assay for nucleic acid detection of Paraginiumus skrjabini and preliminary evaluation of its detection efficiency]

OBJECTIVE

To establish a nucleic acid assay for detection of Paragonimus skrjabini based on the recombinase-aided isothermal amplification (RAA) technique, and to preliminarily evaluate its detection efficiency.

METHODS

The metacercariae of P. skrjabini, P. westermani and Euparagonimus cenocopiosus were isolated from crabs, and genomic DNA was extracted for molecular characterization. The cytochrome coxidase 1 (cox1) gene sequence of P. skrjabini was selected as the target gene fragment, and the primers and probes were designed, screened and synthesized for RAA assay. The genomic DNA of P. skrjabini metacercariae from Jiyuan City and Yiyang County of Luoyang City, Henan Province were used as templates for verification of the fluorescent RAA assay. The fluorescent RAA assay was performed to detect different concentrations of plasmids containing target gene fragment and P. skrjabini metacercariae genomic DNA to determine the sensitivity. Fluorescent RAA assay was performed with recombinant plasmids containing P. skrjabini cox1 gene sequences at different concentrations and P. skrjabini genomic DNA as templates to evaluate its sensitivity, and the genomic DNA of P. westermani, E. cenocopiosus, Clonorchis sinensis and Schistosoma japonicum was detected with fluorescent RAA assay to evaluate its specificity.

RESULTS

P. skrjabini, P. westermani and E. cenocopiosus metacercariae were isolated from crabs, respectively. Molecular characterization and phylogenetic analysis confirmed their homology with the genes sequences of standard Paragonimus strains in GenBank. A fluorescent RAA assay was successfully established for nucleic acid detection of P. skrjabini, and the genomic DNA of P. skrjabini metacercariae from Jiyuan City and Yiyang County of Luoyang City, Henan Province was amplified using the fluorescent RAA assay within 5 min, while the negative control was not amplified. If the recombinant plasmid containing P. skrjabini cox1 gene sequences was used as templates, the fluorescent RAA assay showed the lowest detection limit of 10 copies/μL, and positive amplification was observed within 5 min. If genomic DNA was used as templates, the fluorescent RAA assay showed the lowest detection limit of 10 pg/μL, and all positive amplifications were found within 5 to 10 min. In addition, the fluorescent RAA assay was tested negative for P. westermani, E. cenocopiosus, C. sinensis and S. japonicum.

CONCLUSIONS

A rapid, sensitive and specific fluorescent RAA assay is successfully established for nucleic acid detection of P. skrjabini, which has potential values in rapid field detection and species identification in freshwater crabs in areas endemic for P. skrjabini.

Rescue of BDNF expression by the thalamic parafascicular nucleus with chronic treatment with the mGluR2/3 agonist LY379268 may contribute to the LY379268 rescue of enkephalinergic striatal projection neurons in R6/2 Huntington's disease mice

We have found that daily subcutaneous injection with a maximum tolerated dose of the mGluR2/3 agonist LY379268 (20 mg/kg) beginning at 4 weeks of age dramatically improves the motor, neuronal and neurochemical phenotype in R6/2 mice, a rapidly progressing transgenic model of Huntington's disease (HD). We also previously showed that the benefit of daily LY379268 in R6/2 mice was associated with increases in corticostriatal brain-derived neurotrophic factor (BDNF), and in particular was associated with a reduction in enkephalinergic striatal projection neuron loss. In the present study, we show that daily LY379268 also rescues expression of BDNF by neurons of the thalamic parafascicular nucleus in R6/2 mice, which projects prominently to the striatum, and this increase too is linked to the rescue of enkephalinergic striatal neurons. Thus, LY379268 may protect enkephalinergic striatal projection neurons from loss by boosting BDNF production and delivery via both the corticostriatal and thalamostriatal projection systems. These results suggest that chronic treatment with mGluR2/3 agonists may represent an approach for slowing enkephalinergic neuron loss in HD, and perhaps progression in general.