BACKGROUND:Studies have shown that metformin has anti-inflammatory,anti-tumor,anti-aging and vasoprotective effects,and can inhibit the progression of osteoarthritis,but its specific mechanism of action remains unclear. OBJECTIVE:To investigate the mechanism of metformin on cartilage protection in a rat model of osteoarthritis. METHODS:Forty male Sprague-Dawley rats were randomly divided into four groups(n=10 per group):blank,control,sham-operated,and metformin groups.The blank group did not undergo any surgery.In the sham-operated group,the joint cavity was exposed.In the model group and the metformin group,the modified Hulth method was used to establish the osteoarthritis model.At 1 day after modeling,the rats in the metformin group were given 200 mg/kg/d metformin by gavage,and the model,blank,and sham-operated groups were given normal saline by gavage.Administration in each group was given for 4 weeks consecutively.Hematoxylin-eosin staining,toluidine blue staining,and safranin O-fast green staining were used to observe the morphological structure of rat knee joints.Immunohistochemical staining and western blot were used to detect the protein expression of SOX9,type Ⅱ collagen,a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS5),Beclin1,P62,phosphatidylinositol 3-kinase(PI3K),p-PI3K,protein kinase B(AKT),p-AKT,mammalian target of rapamycin(Mtor),and p-Mtor in rat cartilage tissue. RESULTS AND CONCLUSION:The results of hematoxylin-eosin,toluidine blue and safranin O-fast green staining showed smooth cartilage surface of the knee joints and normal histomorphology in the blank group and the sham-operated group,while in the model group,there was irregular cartilage surface of the knee joint and cartilage damage,with a decrease in the number of chondrocytes and the content of proteoglycans in the cartilage matrix.In the metformin group,there was a significant improvement in the damage to the structure of the cartilage in the knee joints of the rats,and the cartilage surface tended to be smooth,with an increase in the number of chondrocytes and the content of proteoglycans in the cartilage matrix.Immunohistochemistry staining and western blot results showed that compared with the control and sham-operated groups,the expression of SOX9,type Ⅱ collagen,and Beclin1 proteins in the cartilage tissue of rats in the model group was significantly decreased(P<0.05).Conversely,the expression of ADAMTS5,P62,as well as p-PI3K,p-AKT,and p-Mtor proteins was significantly increased(P<0.05).Furthermore,compared with the model group,the expression of SOX9,type Ⅱ collagen,and Beclin1 proteins in the cartilage tissue of rats in the metformin group was significantly increased(P<0.05),while the expression of ADAMTS5,P62,as well as p-PI3K,p-AKT,and p-Mtor proteins was significantly decreased(P<0.05).To conclude,Metformin can improve the autophagy activity of chondrocytes and reduce the degradation of cartilage matrix in osteoarthritis rats by inhibiting the activation of PI3K/AKT/Mtor signaling pathway,thus exerting a protective effect on articular cartilage.

Objective:To investigate the effect of different concentrations and infection durations of varicella-zoster virus (VZV) on nucleotide-binding and oligomerization domain-like receptor protein 3 (NLRP3) inflammasome-related proteins in mouse brain astrocytes.Methods:Mouse brain astrocytes were infected with different dilutions (10 0 [undiluted original concentration] - 10 -7) of cell-free VZV suspension, and the cytopathic effect was observed under a microscope in each group to determine the concentration and infection duration of VZV for subsequent experiments. Some mouse brain astrocytes were infected with cell-free VZV suspension at dilutions of 10 0, 10 -2, 10 -4, and 10 -6, and samples were collected on day 5; some other mouse brain astrocytes were infected with cell-free VZV suspension at the median tissue culture infective dose (TCID 50) of 1.0 × 10 5/ml, and the samples were collected on days 3, 5, 7, and 9, separately; normally cultured mouse brain astrocytes served as control groups in the above experiments. Western blot analysis was performed to determine the protein expression of VZV glycoprotein E (gE), NLRP3, caspase-1, and interleukin-1β (IL-1β) in mouse brain astrocytes in each group. One-way analysis of variance was used for comparisons of data with a normal distribution, and least significant difference- t test was used for multiple comparisons. Results:On day 3 after infection with VZV at the dilution of 10 0, the number of cells decreased, some cells became irregular, lost their original shapes, and showed granular cytoplasm and an unclear nucleus structure, while some cells fused and formed multinucleated giant cells; on day 5, ≥ 50% of cells showed the aforementioned changes and some intercellular spaces were dilated giving a network-like appearance in the 10 0-dilution group; on day 9, the 10 0- - 10 -6- dilution groups all showed dilated intercellular spaces arranged in networks and cytopathic effect in ≥ 50% of cells; on day 10, some cells in the control group exhibited cytoplasmic vacuolation, exfoliation and flotation. Based on these results, the following experiments were conducted with VZV at a concentration gradient ranging from 10 0 to 10 -6 dilutions, and the observations were performed from day 3 to day 9. Western blot analysis showed increased protein expression of VZV gE, NLRP3, caspase-1, and IL-1β in the VZV infection groups compared with the control group, and there were significant differences among different VZV concentration groups ( F = 21.45, 43.82, 21.85, 29.53, respectively, all P < 0.05) and different infection duration groups ( F = 224.10, 78.79, 186.50, 85.08, respectively, all P < 0.05). With the increasing dilution ratios, the expression of inflammasome-related proteins (NLRP3, caspase-1, and IL-1β) decreased, with the highest expression observed in the 10 0-dilution group and the lowest in the 10 -6-dilution group (all P < 0.05). On days 3, 5, and 7 after VZV infection, the expression of NLRP3 inflammasome-related proteins increased over time, with the highest expression observed on day 7 and the lowest on day 3 (all P < 0.05), while their expression decreased on day 9. Conclusion:The expression of NLRP3 inflammasome-related proteins was up-regulated in mouse brain astrocytes after VZV infection, and their expression levels increased along with the increase in the VZV concentration and infection duration in a certain range.

Polymyalgia rheumatica (PMR) is a syndrome characterized by pain and morning stiffness in the neck and shoulder and pelvic girdles, as well as raised acute-phase reactants, with or without systemic symptoms, such as fever. Giant cell arteritis (GCA) is a systemic vasculitis of unclear etiology that involves systemic arteries, principally affecting medium- and large-sized arteries with skipped, segmental alterations and granulomatous vasculitis seen on histopathology. In China, epidemiological data describing GCA are still limited; thus, the prevalence might be underestimated. The involvement of vessels in GCA can cause irreversible visual impairment or loss and stroke, which are serious complications. PMR is three times more prevalent than GCA, and other specific diseases should be excluded before the diagnosis is established. PMR symptoms can be present in 40%-60% of patients with GCA. Conversely, GCA can develop in 15% of patients with PMR. Chinese Rheumatology Association, based on the clinical diagnosis and treatment guidelines in 2005, utilizing the experience and guidelines of diagnosis and treatment at home and abroad, formulated this specification to standardize the diagnosis and treatment of GCA and PMR and improve the patient′s prognosis.

China has classified the Corona Virus Disease 2019(COVID-19) as a statutory category B infectious disease and managed it according to Category B since January 8, 2023.In view that Omicron variant is currently the main epidemic strain in China, in order to guide the treatment of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) infection in children with the times, refer to the Diagnosis and Treatment Protocol for Novel Coronavirus Infection (Trial 10 th Edition), Expert Consensus on Diagnosis, Treatment and Prevention of Novel Coronavirus Infection in Children (Fourth Edition) and the Diagnosis and Treatment Strategy for Pediatric Related Viral Infections.The Expert Consensus on the Diagnosis, Treatment and Prevention of Novel Coronavirus Infection in Children (Fifth Edition) has been formulated and updated accordingly on related etiology, epidemiology, pathogenic mechanism, clinical manifestations, auxiliary examination, diagnosis and treatment, and added key points for the treatment of COVID-19 related encephalopathy, fulminating myocarditis and other serious complications for clinical reference.

Objective: To evaluate the value of multi-detector CT (MDCT) upper airway imaging in the diagnosis of obstructive sleep apnea hypopnea syndrome ( OSAHS) and in determining the location of upper airway obstruction． Methods : MDCT was used to scan the upper airways of 85 clinically confirmed adult patients with different degrees of OSAHS (73 males and 12 females) in calm breathing phase and forced inhalation phase and 60 normal adults (50 males and 10 females) in calm breathing phase to obtain nasal cavity，nasopharynx，palatopharynx and oglosopharynx volumes．Parapharyngeal fat volume was measured in OSAHS patients and normal subjects．In addition，three groups of clinical data related to OSAHS patients were recorded，including sleep apnea hypopnea index (AHI) ，body mass index ( BMI) and lowest blood oxygen saturation ( LaSO2 ) ．Finally，the measured data and clinical data of each group were statistically analyzed. Results : The volume of nasopharynx and palatopharynx in the calm breathing group was significantly smaller than that in the control group，with statistical significance．Palatopharyngeal volume forced inspiratory phase was significantly smaller than calm breathing phase in the experimental group．The parapharyngeal fat volume in the experimental group was significantly higher than that in the control group．AHI was positively correlated with BMI and parapharyngeal fat volume．LaSO2 was negatively correlated with AHI and BMI，respectively． Conclusion MDCT upper airway imaging has good clinical application value in the diagnosis，treatment and postoperative evaluation of OSAHS disease due to the significant anatomical difference between OSAHS patients and normal subjects.

Objective:To investigate effects of the autophagy inducer rapamycin and autophagy inhibitor 3-methyladenine on viral structures and biosynthesis of functional proteins in dorsal root ganglia in a guinea pig model of varicella-zoster virus (VZV) infection, and to explore their possible mechanisms.Methods:VZV was cultured and proliferated in human embryonic lung fibroblasts (HELFs) , and peripheral blood mononuclear cells (PBMCs) were isolated from guinea pigs. VZV-HELFs and PBMCs were co-cultured for 18-20 hours, and VZV-PBMCs were collected by centrifugation. Thirty-two guinea pigs were randomly and equally divided into 4 groups (8 mice in each group) : blank control group was injected with autologous PBMCs via the medial canthal venous plexus; autophagy inhibition group, autophagy induction group, and VZV infection group were intraperitoneally injected with 3 mg/kg 3-methyladenine solution, 0.5 mg/kg rapamycin solution, and the same volume of 0.9% NaCl solution respectively, followed 2 hours later by injections with 50 μl of VZV-PBMCs via the medial canthal venous plexus. Fourteen days later, the guinea pigs in each group were sacrificed, and dorsal root ganglion tissues were collected. The transmission electron microscope was used to observe the morphology of virus particles, as well as the morphology and number of autophagic vesicles, Western blot analysis was performed to determine the expression of VZV nucleocapsid protein (NCP) , immediate-early protein 62 (IE62) , and autophagy-related proteins Beclin-1 and p62, and immunohistochemical study to determine the expression of anti-VZV antibodies in VZV-infected dorsal root ganglia. Statistical analysis was carried out by using two-independent-sample t test, one-way analysis of variance, least significant difference- t test or Kruskal-Wallis H test. Results:Nucleocapsid-containing virions and scattered autophagosomes were seen in the dorsal root ganglia in the VZV infection group under the transmission electron microscope. The number of autophagic vesicles significantly differed among the blank control group, VZV infection group, autophagy induction group and autophagy inhibition group ( M[ Q1, Q3]: 0, 5[4, 6], 7[5, 9], 0, respectively; H = 135.60, P < 0.01) , and was significantly higher in the VZV infection group than in the blank control group and autophagy inhibition group (both P < 0.05) , as well as in the autophagy induction group than in the autophagy inhibition group ( P<0.05) , but there was no significant difference between the VZV infection group and autophagy induction group ( P>0.05) . Western blot analysis showed that the expression level of IE62 protein was significantly higher in the VZV infection group (1.49 ± 0.06) than in the blank control group (0.50 ± 0.09, t = 9.17, P < 0.05) ; the expression of anti-VZV antibodies was significantly lower in the autophagy inhibition group than in the autophagy induction group and VZV infection group ( t = 9.24, 7.78, respectively, both P < 0.01) , while there was no significant difference between the autophagy induction group and VZV infection group ( P > 0.05) . Conclusion:Autophagy occurred in the dorsal root ganglia of guinea pigs after VZV infection; the inhibition of autophagy could affect the structure of VZV and decrease the expression of VZV functional proteins in the dorsal root ganglia of guinea pigs.

Monkeypox is a zoonotic disease.Previous studies have shown that children are vulnerable to monkeypox and are also at high risk for severe disease or complications.In order to improve pediatricians′ understanding of monkeypox and achieve early detection, early diagnosis, early treatment and early disposal, the committee composed of more than 40 experts in the related fields of infectious diseases, pediatrics, infection control and public health formulate this expert consensus, on the basis of the latest clinical management and infection prevention and control for monkeypox released by the World Health Organization (WHO), the guidelines for diagnosis and treatment of monkeypox (version 2022) issued by National Health Commission of the People′s Republic of China and other relevant documents.During the development of this consensus, multidisciplinary experts have repeatedly demonstrated the etiology, epidemiology, transmission, clinical manifestations, laboratory examinations, diagnosis and differential diagnosis, treatment, discharge criteria, prevention, case management process and key points of prevention and control about monkeypox.

Since December 2019, severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) infections have raged globally for more than 2 years.China has always adopted scientific and effective prevention and control measures to achieved some success.However, with the continuous variation of SARS-CoV-2 cases and imported cases from abroad, the prevention and control work has become more difficult and complex.With the variation of the mutant strain, the number of cases in children changed, and some new special symptoms and complications were found, which proposed a new topic for the prevention and treatment of SARS-CoV-2 infection in children in China.Based on the third edition, the present consensus according to the characteristics of the new strain, expounded the etiology, pathology, pathogenesis, and according to the clinical characteristics and experience of children′s cases, and puts forward recommendations on the diagnostic criteria, laboratory examination, treatment, prevention and control of children′s cases for providing reference for further guidance of effective prevention and treatment of SARS-CoV-2 infection in children in China.

2019 novel coronavirus(2019-nCoV) outbreak is one of the public health emergency of international concern.Since the 2019-nCoV outbreak, China has been adopting strict prevention and control measures, and has achieved remarkable results in the initial stage of prevention and control.However, some imported cases and sporadic regional cases have been found, and even short-term regional epidemics have occurred, indicating that the preventing and control against the epidemic remains grim.With the change of the incidence proportion and the number of cases in children under 18 years old, some new special symptoms and complications have appeared in children patients.In addition, with the occurrence of virus mutation, it has not only attracted attention from all parties, but also proposed a new topic for the prevention and treatment of 2019-nCoV infection in children of China.Based on the second edition, the present consensus further summarizes the clinical characteristics and experience of children′s cases, and puts forward recommendations on the diagnostic criteria, laboratory examination, treatment, prevention and control of children′s cases for providing reference for further guidance of treatment of 2019-nCoV infection in children.

At present, severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is still rampant worldwide.As of September 10, 2021, there were about 222 million confirmed cases of corona virus disease 2019(COVID-19)and more than 4.6 million deaths worldwide.With the development of COVID-19 vaccines and the gradual vaccination worldwide, the increasing number of cases in children and unvaccinated young people has drawn attention.According to World Health Organization surveillance data, the proportion of COVID-19 infection cases in children gradually increased, and the proportion of cases in the age groups of under 5 years and 5-14 years increased from 1.0% and 2.5% in January 2020 to 2.0% and 8.7% in July 2021, respectively.At present, billions of adults have been vaccinated with various COVID-19 vaccines worldwide, and their protective effects including reducing infection and transmission, reducing severe disease and hospitalization, and reducing death, as well as high safety have been confirmed.Canada, the United States, Europe and other countries have approved the emergency COVID-19 vaccination in children and adolescents aged 12 to 17 years, and China has also approved the phased vaccination of COVID-19 vaccination in children and adolescents aged 3 to 17 years. For smooth advancement and implementation of COVID-19 vaccination in children, academic institutions, including National Clinical Research Center for Respiratory Diseases, National Center for Children′s Health, and The Society of Pediatrics, Chinese Medical Association organized relevant experts to reach this consensus on COVID-19 vaccination in children.