[Epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023]

Objective: To understand the epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023. Methods: The data of this study were collected from the ARI surveillance data from 16 provinces in China from 2009 to 2023, with a total of 28 278 ARI cases included in the study. The clinical specimens from ARI cases were screened for HRSV nucleic acid from 2009 to 2023, and differences in virus detection rates among cases of different age groups, regions, and months were analyzed. Results: A total of 28 278 ARI cases were enrolled from January 2009 to September 2023. The age of the cases ranged from<1 month to 112 years, and the age M (Q1, Q3) was 3 years (1 year, 9 years). Among them, 3 062 cases were positive for HRSV nucleic acid, with a total detection rate of 10.83%. From 2009 to 2019, the detection rate of HRSV was 9.33%, and the virus was mainly prevalent in winter and spring. During the Corona Virus Disease 2019 (COVID-19) pandemic, the detection rate of HRSV fluctuated between 6.32% and 18.67%. There was no traditional winter epidemic peak of HRSV from the end of 2022 to the beginning of 2023, and an anti-seasonal epidemic of HRSV occurred from April to May 2023. About 87.95% (2 693/3 062) of positive cases were children under 5 years old, and the difference in the detection rate of HRSV among different age groups was statistically significant (P<0.001), showing a decreasing trend of HRSV detection rate with the increase of age (P<0.001). Among them, the HRSV detection rate (25.69%) was highest in children under 6 months. Compared with 2009-2019, the ranking of HRSV detection rates in different age groups changed from high to low between 2020 and 2023, with the age M (Q1, Q3) of HRSV positive cases increasing from 1 year (6 months, 3 years) to 2 years (11 months, 3 years). Conclusion: Through 15 years of continuous HRSV surveillance analysis, children under 5 years old, especially infants under 6 months old, are the main high-risk population for HRSV infection. During the COVID-19 pandemic, the prevalence and patterns of HRSV in China have changed.

[Progress in platelets and tuberculosis]

Platelets are important cells in hemostatic and coagulative reactions. Interestingly, platelets-related immunopathological mechanism and clinical research have become one of the hot research topics in tuberculosis at home and abroad in recent years. Platelets get involved in host chronic inflammation and pulmonary immune response, thus playing a negative regulatory role in tuberculosis. This is achieved through direct internalization of Mycobacterium tuberculosis and indirect interaction with immune cells. In addition, patients with tuberculosis often have thrombocytosis, and there is increasing evidence that anti-platelet therapy as a host-directed therapy has demonstrable clinical benefit in tuberculosis control. Platelet inhibition may be an emerging therapeutic strategy for tuberculosis. This review aims to highlight the research progress in platelets and tuberculosis.

[Progress and prospect of clinical application of anti-rabies virus monoclonal antibody preparation]

Rabies is a severe infectious disease caused by the rabies virus, which seriously damages the central nervous system. Once it occurs, the fatality rate is close to 100%. The World Health Organization's position paper on rabies vaccines recognizes that rabies immunoglobulin (RIG) should be used for post-exposure prophylaxis (PEP) in all category Ⅲ exposure for the first time, as well as in category Ⅱ exposure that suffer from severe immune deficiency, long-term massive use of immunosuppressants, and head and face exposure. The anti-rabies virus monoclonal antibody has high purity and specific activity, can be produced on a sustainable scale, and has no risk of blood source virus contamination. Preclinical pharmacodynamic studies and clinical trial results of the anti-rabies virus monoclonal antibody preparation have confirmed that the preparation has a broad-spectrum neutralization effect on the rabies virus. Additionally, its combined application with the vaccine has little impact on the active immunity of the vaccine. Therefore, the anti-rabies virus monoclonal antibody preparation shows great potential for clinical application in PEP.

[Hepatic pathological characteristics and factors influencing alanine transaminase value below twice the upper limit of normal in patients with chronic hepatitis B]

Objective: To analyze the hepatic pathological characteristics and factors influencing an alanine transaminase value below twice the upper limit of normal in patients with chronic hepatitis B (CHB) and further explore the optimal ALT threshold strategy for initiating antiviral therapy. Methods: Clinical data of treatment-naïve CHB patients who underwent liver biopsies from January 2010 to December 2019 were retrospectively collected. Multiple regression models were used to explore the ALT levels and significant risk of hepatic histological changes (≥G2/S2). Receiver operating characteristic curve was used to evaluate the value of different models in diagnosing liver tissue inflammation≥G2 or fibrosis ≥ S2. Results: A total of 447 eligible CHB patients, with a median age of 38.0 years and 72.9% males, were included. During ALT normalization, there was significant liver inflammation (≥G2) and fibrosis (≥S2) in 66.9% and 53.0% of patients, respectively. With an ALT rise of 1-2×ULN, the proportions of liver inflammation≥G2 and fibrosis≥S2 were 81.2% and 60.0%, respectively. After adjusting for confounding factors, higher ALT levels (> 29 U/L) were found to be associated with significant liver inflammation (OR: 2.30, 95% CI: 1.11 ~ 4.77) and fibrosis (OR: 1.84, 95% CI: 1.10 ~ 3.09). After the measurement of glutamyltransferase-platelet ratio (GPR), the proportion of CHB patients with≥G2/S2 was significantly reduced under different treatment thresholds of ALT standards, and in particular, the erroneous evaluation of liver fibrosis≥S2 was significantly improved (33.5% to 57.5%). Conclusion: More than half of CHB patients have a normal ALT or one within 2 × ULN, regardless of whether or not there is apparent inflammation and fibrosis. GPR can significantly improve the precise assessment of different conditions of treatment thresholds for the ALT value in CHB patients.

[Measuring and analysis of the shoulder circumferences of 840 adults' permanent teeth crown preparations]

Objective: To measure and analyze the shoulder circumferences of adults' permanent teeth crown preparations based on data collected through the intraoral scanning, so as to provide dental anatomy data for clinical diagnosis and analysis. Methods: Intraoral scanning data of 840 complete crown preparations were collected, and were entrusted to the World Dental Laboratory Co., Ltd. in Fuzhou between March 2021 and June 2022. Except the data of the third molar, the rest data were categorized in terms of 14 tooth positions in the upper and lower jaw (each category involved 30 samples from male group and 30 samples from female group). Image measurement software was used to measure the shoulder circumferences of permanent teeth crown preparations. And analysis was conducted to reveal the difference of shoulder circumference diameters between male and female groups. And then they were grouped according to the mean value at each tooth position, on the premise that the difference between the maximum and minimum values and the mean value of the entire group was≤±1.00 mm. Analysis were further conducted to determine the differences of shoulder circumference diameters between each dental position and the differences between male and female in the same groups. Results: Bivariate analysis of variance showed that gender had no effect on the shoulder circumference of full crown preparations (F=0.55, P=1.457), while tooth position had a significant impact on the shoulder circumference of full crown preparations (F=273.15, P<0.001). The samples were classified into 5 groups according to the mean values of shoulder circumference diameters relating to each tooth position. Statistical analysis showed that Group 1, covering maxillary lateral incisor, mandibular central incisor and mandibular lateral incisor, had shoulder circumference with diameters of (16.62±2.21) mm; Group 2, consisting of maxillary central incisor, maxillary cusp, mandibular cusp, mandibular first premolar and mandibular second premolar, had diameters of (20.78±2.48) mm; Group 3, consisting of maxillary first premolar and maxillary second premolar, had diamerters of (22.09±2.72) mm; Group 4, covering maxillary first molar, maxillary second molar and mandibular first molar, had diamerters of (30.21±2.67) mm; while group 5, with mandibular second molar alone its member, had diamerters of (31.34±3.18) mm. The difference among the 5 groups was statistically significant (P<0.05). Conclusions: Significant differences of shoulder circumference diameters could be found between different tooth positions, while at the same tooth position, the differences between male and female are not significant. The 14 tooth positions could be grouped into 5 groups according to their shoulder circumference diameters. Future research could take the grouping as reference.

[Safety and efficacy of a new domestic distal perforated stent graft in the treatment of Stanford type B aortic dissection]

Objective: To evaluate the safety and efficacy of a new domestic distal perforated stent graft (Talos stent) in the treatment of Stanford type B aortic dissection (TBAD). Methods: Twenty-five patients with TBAD treated with Talos stent in Yan'an Hospital Affiliated to Kunming Medical University from February 2018 to December 2019 were selected as the research subjects. Intraoperative angiography was performed to determine the number of branch arteries that remained after stent release. On postoperative day 5 (POD5), the pain intensity of the patients was evaluated by visual analog scale (VAS). The computed tomography angiography (CTA) of the patients before operation, 6 months and 12 months after operation were compared including aortic diameter, true lumen diameter, and false lumen diameter at the level of tracheal bifurcation. Follow-up was performed 1 month, 6 months, 12 months, and 24 months after surgery, and the occurrence of stent-related adverse events, reoperation and survival rate were recorded. Results: The enrolled patients included 19 males and 6 females, aged (52.6±11.1) years. Intraoperative angiography showed that 4 (1, 7) branch arteries were preserved, and the VAS score was 1 (0, 1) on POD5. The aortic diameters at the level of the tracheal bifurcation were (34.9±1.1) mm, (34.6±0.9) mm and (34.8±1.0) mm before surgery, 6 months and 12 months after surgery, and there was no significant difference (P=0.926); the diameters of the main true lumen at the level of the tracheal bifurcation were (13.3±1.6) mm, (21.8±1.0) mm and (22.3±1.1) mm before surgery, 6 months and 12 months postoperatively, while the diameters of the main false lumen at the level of the tracheal bifurcation were (20.8±2.2) mm, (4.5±1.5) mm, and (4.6±1.7) mm, respectively. Compared with before surgery, the diameter of true lumen increased significantly 6 months and 12 months after surgery (both P<0.001), while the diameter of false lumen decreased (both P<0.001). No stent-related adverse events occurred within 30 days after surgery, no secondary operations occurred within 12 months after surgery, no type Ⅰ and type Ⅲ endoleaks, no deaths or cases of paraplegia were reported, and the stent structure and position remained good. There were no deaths or paraplegia cases 24 months postoperatively, and no stent-related adverse events occurred. Conclusion: Using Talos stent in the treatment of TBAD can effectively help remodel the aorta, while preserve the intercostal artery and spinal artery, with good clinical effect and safety.

[Clinical features and influencing factors of long-term prognosis in patients with tuberculous meningitis]

Objective: To investigate the clinical features and influencing factors of long-term prognosis of tuberculous meningitis(TBM), and to provide a recommendation for treatment and early intervention of TBM. Methods: Clinical data of TBM patients were retrospectively collected at Peking Union Medical College Hospital from January 2014 to December 2021. Patients who were followed-up more than one year were divided into two groups according to modified Rankin Scale (mRS). Risk factors associated with long-term prognosis were analyze by conditional logistic stepwise regression. Results: A total of 60 subjects were enrolled including 33 (55%) males and 27 (45%) females with age 15-79 (44.5±19.8) years. There were 30 cases (50%) complicated with encephalitis, 21 cases (35%) with miliary tuberculosis. The diagnosis was microbiologically confirmed in 22 patients (36.7%), including 5 cases (22.7%, 5/22) by acid-fast staining, 8 cases (36.4%, 8/22) by Mycobacterium tuberculosis (MTB) culture, and 20 cases (90.9%, 20/22) by molecular biology. The median follow-up period was 52(43, 66 ) months in 55 cases surviving more than one year. Among them, 40 cases (72.7%) were in favorable group (mRS 0-2) and 15 cases (27.3%) were in unfavorable group (mRS 3-6) with poor prognosis. The mortality rate was 20% (11/55). Elderly (OR=1.06, P=0.048 ) , hyponatremia(OR=0.81,P=0.020), high protein level in cerebrospinal fluid (CSF) (OR=3.32,P=0.033), cerebral infarction(OR=10.50,P=0.040) and hydrocephalus(OR=8.51,P=0.049) were associated with poor prognosis in TBM patients. Conclusions: The mortality rate is high in patients with TBM. Molecular biology tests improves the sensitivity and shorten the diagnosis time of TBM. Elderly, hyponatremia, high protein level in CSF, cerebral infarction and hydrocephalus are independent risk factors of long-term survival in TBM patients.

[Development of a Ranking Tool for Scientificity, Transparency and Applicability of Clinical Practice Guidelines]

Objective: To address the limitations of existing methods and tools for evaluating clinical practice guidelines, we aimed to develop a comprehensive instrument focusing on the three main dimensions of guideline development: scientificity, transparency, applicability. We will use it to rank the guidelines according to the scores. We abbreviated it as STAR, and its reliability, validity and usability were also tested. Methods: A multidisciplinary expert working group was set up, including methodologists, statisticians, journal editors, medical professionals, and others. Scoping review, Delphi methods and hierarchical analysis were used to determine the final checklist of STAR. Results: The new instrument contained 11 domains and 39 items. Intrinsic reliability of each domain was indicated by Cronbach's α coefficient, with a average value of 0.646. The Cohen's kappa coefficients for methodological evaluators and clinical evaluators were 0.783 and 0.618. The overall content validity index was 0.905. The R2 for the criterion validity analysis was 0.76. The average score for usability of the items was 4.6, and the mean time spent to evaluate each guideline was 20 minutes. Conclusion: The instrument has good reliability, validity and evaluating efficiency, and can be used for evaluating and ranking guidelines more comprehensively.

[Pregnancy outcomes in patients with adenomyosis with fertility requirements: retrospective analysis of clinical data from real world]

Objective: To retrospectively analyze the pregnancy outcomes of patients with adenomyosis requiring fertility in a single center under real world condition. Methods: From June 2015 to May 2020, 231 cases of pregnancy complicated with adenomyosis diagnosed by ultrasound with fertility requirements were treated in the Women's and Children's Hospital Affiliated to Qingdao University with complete clinical data. And they were divided into three groups according to the treatment of adenomyosis before pregnancy: expectation group, drug group and operation group. The relevant data before pregnancy of the three groups were analyzed, and the pregnancy outcomes of the patients were summarized. According to whether the early pregnancy was treated with medication, the patients who were naturally conceived without symptoms of threatened abortion were divided into observation group and fetus protection group, and the pregnancy outcomes of the two groups were compared. Results: (1) Compared with the expectation group, the ages of patients in the drug group and the operation group were larger [(31.5±1.8) vs (34.1±3.7) vs (36.9±3.6) years old], and the difference was statistically significant (P<0.05). Only 9 patients (11.5%, 9/78) had clinical symptoms in the expectation group, while the patients in the drug group and the operation group had a higher proportion of dysmenorrhea and increased menstrual volume. The uterine volume of the drug group and the operation group were larger than that of the expectation group [(151±46) vs (166±27) vs (97±18) cm³], the difference was statistically significant (P<0.05). 78.6% (33/42) of the operation group were focal adenomyosis. The proportion of natural pregnancy in the expectation group was 97.4% (76/78), and in vitro fertilization and embryo transfer was mainly used in the drug group and the operation group. (2) The abortion rates of the three groups were 48.7% (26/111), 4/17, 67.5% (27/78) respectively. Compared with the drug group and the operation group, the preterm birth rate was lower [55.9% (33/111) vs 11/17 vs 12.5% (5/78)] and the natural delivery rate was higher [44.1% (26/111) vs 4/17 vs 67.5% (27/78)] in the expectation group. (3) There were 89 cases of spontaneous pregnancy without threatened abortion symptoms, including 31 cases in the observation group and 58 cases in the fetus protection group. Compared with the observation group, the abortion rate of patients in the fetus protection group was lower [41.9% (13/31) vs 34.5% (20/58)], and the difference was statistically significant (P<0.05). Conclusions: Patients with adenomyosis who have fertility requirements should be comprehensively evaluated and individualized treatment plans should be given. Pregnancy patients with adenomyosis have a high rate of miscarriage, and they should be included in the management of high-risk pregnant women. Active fetal protection treatment during early pregnancy might improve pregnancy outcomes.

[Mechanism of Mycobacterium tuberculosis on interleukin-6 receptor 3'-untranslated region methylation in CD4+T cells]

Objective: To investigate the role and mechanism of DNA methylation in Mycobacterium tuberculosis (MTB lysate) -induced downregulation of interleukin-6 receptor(IL-6R) expression in CD4⁺T cells. Methods: A prospective study was conducted. Bisulfite sequencing (BSP) was applied to determine the methylation levels of CpG island in IL-6R promoter region and 3'untranslated region (3'UTR) region in CD4⁺T cells from peripheral blood mononuclear cells (PBMC) of control group (healthy person, n=10) and TB group (tuberculosis patients, n=10) in Shenzhen Third People's Hospital between 2019 and 2020. Quantitative reverse transcription-PCR (RT-qPCR) and Western blotting were used to detect the expression of IL-6R, DNMT1, DNMT3A and DNMT3B in MTB lysate-stimulated CD4⁺T cells and Jurkat E6-1 cells. Furthermore, PBMC in control group and Jurkat E6-1 cells activated by anti-CD3/CD28 antibody were stimulated by MTB lysates to detect the methylation levels of CpG island and IL-6R and DNMT expression. Transcriptional activity of differently methylation regions of IL-6R 3'UTR was detected by using luciferase reporter gene system. Results: IL-6R expression in TB group was lower than that in control group, but DNMT1 and DNMT3B expressions were higher than those in control group in CD4⁺T cells isolated from PBMC. There was no significant difference in the methylation rate of IL-6R promoter CpG island of CD4⁺T cells between control and TB group. However, the methylation rates of CpG island in 3'UTR region were significantly higher (P<0.001) in TB (69.5%±3.4%), compared with control (54.3%±4.7%). Besides, IL-6R expression was lower than unstimulated, while DNMT1 and DNMT3B expression was higher than unstimulated after MTB lysate-stimulation of activated control PBMC in vitro. The methylation rate of CpG island in IL-6R 3'UTR region of CD4⁺T cells increased from 58.8%±11.6% to 79.4%±10.9% (P<0.001) after MTB lysate-stimulated PBMC of the control. The same results were observed in the MTB lysate-stimulated CD4⁺T cells isolated from PBMC in control and Jurkat E6-1 cell line. Furthermore, IL-6R expression after co-treatment of the DNA methyltransferase inhibitor decitabine (5-aza) with MTB lysate was higher than that stimulated by MTB lysate alone. In addition, the methylation levels of CpG islands in the 3' UTR region of IL-6R were lower than those stimulated by MTB lysates alone after co-treatment of the DNA methyltransferase inhibitor decitabine (5-aza) with MTB lysates. The transcriptional activity of the fully unmethylated IL-6R 3'UTR CpG island reporter gene was higher than that of the fully methylated IL-6R 3'UTR CpG island. Conclusions: MTB lysates stimulation inhibited IL-6R expression transcriptionalely as well as on the protein level by inducing hypermethylation of CpG island in IL-6R 3'UTR region of CD4⁺T cells. The hypermethylation of CpG island in IL-6R 3'UTR region of CD4⁺T cells induced by MTB may be related to the increased expression of DNMT1 and DNMT3B.

[Esthetic evaluation of conventional and socket shield technique immediate implant restoration]

Objective: To evaluate the pink and white esthetics of conventional and socket shield technique (SST) immediate implant restoration. Methods: Thirty volunteers were recruited according to preset criteria, and were assigned to 3 groups. Natural teeth group (ten undergraduates or postgraduates from Peking University School and Hospital of Stomatology in January 2020, n=10): all volunteers' maxillary anterior teeth were natural teeth with healthy gingiva, and none of the teeth were restored by crowns or composite. Conventional group and SST group (patients had a maxillary central incisor immediate implant placed in Department of Prosthodontics, Peking University School and Hospital of Stomatology during October 2016 to January 2021, n=10 for each group): the volunteer had an unrestored natural maxillary central incisor, and the contralateral maxillary central incisor was restored by conventional or SST immediate implant placement, temporization and all ceramic final restoration, photos were taken 12 months post-surgery. Three groups of evaluators namely layperson (staff from Second Clinical Division of Peking University School and Hospital of Stomatology and 2 family members, n=10), dental students (class 2015 undergraduates from Peking University School and Hospital of Stomatology, n=10) and prosthodontists (from Department of Prosthodontics, Peking University School and Hospital of Stomatology, n=10) were invited to assess the esthetics using pink esthetic score (PES) and white esthetic score (WES). The results were statistically analyzed. Results: PES and WES of natural teeth group [9(8, 10) and 8(7, 10)] were significantly higher than conventional group [7(6,8) and 7(6,9)] (H=287.08, 132.79,P<0.01) and SST group [7(6, 9) and 8(7, 9)] (H=216.01, 101.21, P<0.01). SST group yielded higher PES than the conventional group (H=-71.06, P<0.01), yet had similar WES (H=-31.57, P>0.05). Dental students had significant lower PES and WES than prosthodontists (H=-120.90, -218.86, P<0.01) and layperson (H=-109.55, 134.97, P<0.01). Prosthodontists and layperson got similar PES (H=-11.36, P>0.05), however yielded different WES (H=-83.89, P<0.01). Conclusions: SST immediate implant placement obtained better pink esthetics than conventional protocol 12-month after implant surgery, profession may have significant impact on evaluators during pink and white esthetic evaluation.

[Research progress on the low-temperature degradation of zirconia in prosthetic dentistry]

Zirconia is widely used in the field of dentistry because of its superior mechanical and esthetic characteristics. However, the tetragonal zirconia polycrystal restorations commonly used in clinics will degrade at low temperatures in the oral environment, resulting in increased surface roughness, microcracks, and decreased mechanical properties. Low-temperature degradation of zirconia can be affected by grain size, stress, stabilizer content and type, surface treatment, sintering conditions, and other factors. Through a literature review and analysis, this review summarizes the research progress on the low-temperature degradation of zirconia in prosthetic dentistry to provide references for the improvement of zirconia in clinical and research applications.

[Metagenomic data-analysis reveals enrichment of lipopolysaccharide synthesis in the gut microbiota of atrial fibrillation patients]

Objective: To investigate the functional changes of key gut microbiota (GM) that produce lipopolysaccharide (LPS) in atrial fibrillation (AF) patients and to explore their potential role in the pathogenesis of AF. Methods: This was a prospective cross-sectional study. Patients with AF admitted to Beijing Chaoyang Hospital of Capital Medical University were enrolled from March 2016 to December 2018. Subjects with matched genetic backgrounds undergoing physical examination during the same period were selected as controls. Clinical baseline data and fecal samples were collected. Bacterial DNA was extracted and metagenomic sequencing was performed by using Illumina Novaseq. Based on metagenomic data, the relative abundances of KEGG Orthology (KO), enzymatic genes and species that harbored enzymatic genes were acquired. The key features were selected via the least absolute shrinkage and selection operator (LASSO) analysis. The role of GM-derived LPS biosynthetic feature in the development of AF was assessed by receiver operating characteristic (ROC) curve, partial least squares structural equation modeling (PLS-SEM) and logistic regression analysis. Results: Fifty nonvalvular AF patients (mean age: 66.0 (57.0, 71.3), 32 males(64%)) were enrolled as AF group. Fifty individuals (mean age 55.0 (50.5, 57.5), 41 males(82%)) were recruited as controls. Compared with the controls, AF patients showed a marked difference in the GM genes underlying LPS-biosynthesis, including 20 potential LPS-synthesis KO, 7 LPS-biosynthesis enzymatic genes and 89 species that were assigned as taxa harbored nine LPS-enzymatic genes. LASSO regression analysis showed that 5 KO, 3 enzymatic genes and 9 species could be selected to construct the KO, enzyme and species scoring system. Genes enriched in AF group included 2 KO (K02851 and K00972), 3 enzymatic genes (LpxH, LpxC and LpxK) and 7 species (Intestinibacter bartlettii、Ruminococcus sp. JC304、Coprococcus catus、uncultured Eubacterium sp.、Eubacterium sp. CAG:251、Anaerostipes hadrus、Dorea longicatena). ROC curve analysis revealed the predictive capacity of differential GM-derived LPS signatures to distinguish AF patients in terms of above KO, enzymatic and species scores: area under curve (AUC)=0.957, 95%CI: 0.918-0.995, AUC=0.940, 95%CI 0.889-0.991, AUC=0.972, 95%CI 0.948-0.997. PLS-SEM showed that changes in lipopolysaccharide-producing bacteria could be involved in the pathogenesis of AF. The key KO mediated 35.17% of the total effect of key bacteria on AF. After incorporating the clinical factors of AF, the KO score was positively associated with the significantly increased risk of AF (OR<0.001, 95%CI:<0.001-0.021, P<0.001). Conclusion: Microbes involved in LPS synthesis are enriched in the gut of AF patients, accompanied with up-regulated LPS synthesis function by encoding the LPS-enzymatic biosynthesis gene.

[Immunogenicity and safety of a boost dose of measles, mumps, and rubella combined vaccine for 4-6 years old children]

Objective: To investigate the immunogenicity and safety of a boost dose of measles, mumps, and rubella combined vaccine (MMR) for children 4 to 6 years old. Methods: Children, aged 4 to 6 years old, had vaccinated with 1 dose of measles and rubella combined vaccine(MR) at the age of 8 months and 1 dose of MMR vaccine at 18-months, were recruited in Shanxi, Inner Mongolia, and Beijing, respectively. All children were assigned into 4, 5 and 6-year-old group. The children who met inclusion and exclusion criteria were vaccinated with 1 dose MMR vaccine, and were collected blood samples before vaccination and 35 to 42 d after the vaccination. During the study period, adverse events were collected at 30 min, 1 d, 2 d, 3 d, 4-12 d, and 13 to 42 days after vaccination. Serum was tested for IgG antibodies against measles, mumps and rubella. Geometric mean concentrations (GMC) of measles, mumps, and rubella antibodies were compared among groups by analysis of variance or non-parametric test. Seropositive rates and adverse event rates were compared among groups by Chi-square test or Fisher exact test. Results: A total of 500 children were included in immunogenicity analysis and 535 children were included in safety analysis. The overall adverse event rate was 20.37%, the most of severity for adverse events was mild. The rates of local and systemic adverse events were 0.37% and 20.00%, respectively. Symptoms of local adverse events were redness. The main systemic adverse events were fever, followed by cough, rash and runny nose. Received a dose of MMR vaccine for booster immunization, the seropositive rates of measles antibody, mumps antibody and rubella antibody were above 99% for all 3 age groups, and there was no significant difference between groups. There were significant differences in mumps antibody GMC among groups (P=0.042), but no significant differences in measles and rubella antibodies GMC. Conclusion: The immunogenicity and safety of a boosted MMR vaccintion in children aged 4, 5 and 6 years were all similar good.

[Multicenter cross-sectional investigation on the cleaning status and influencing factors of skin cleaning outside the wound in adult trauma patients]

Objective: To investigate the status and influencing factors of skin cleaning outside wound (hereinafter referred to as skin) in adult trauma patients. Methods: A multicenter cross-sectional investigation was conducted. From September 1 to 30, 2020, a total of 952 adult trauma patients who met the inclusion criteria were admitted to wound care clinics or trauma surgery wards of 13 military or local Grade Ⅲ Level A hospitals, including the General Hospital of the Eastern Theater Command of People's Liberation Army and the Army Medical Center, etc. A self-designed questionnaire on cleaning status of skin in trauma patients was released through the "questionnaire star" website to investigate basic information such as gender, age, education level, living status, and self-care ability, trauma information such as cause of injury, wound duration, trauma site, trauma depth, wound pain, wound peculiar smell, and wound cleaning solution, and skin cleaning status after injury such as whether to clean or not, cleaning method, cleaning frequency, cleaning duration in each time, or reasons for not cleaning. The patients who cleaned skin regularly after injury were included in cleaning group, and the other patients were included in no cleaning group. The basic information, trauma information, and skin cleaning status after injury of patients in 2 groups were investigated. Data were statistically analyzed with chi-square test, and binary multivariate logistic regression analysis was performed on indicators with statistically significant differences between the two groups to screen the independent influencing factors of skin cleaning in trauma patients. Results: A total of 952 questionnaires were received, and the recovery rate was 100%. Three invalid questionnaires were eliminated, and 949 valid questionnaires were obtained, with an effective rate of 99.68%. In 949 patients, there were 461 (48.6%) males and 488 (51.4%) females, aged 18-100 (50±18) years. Most patients were less than 60 years old, lived with their families, and could take care of themselves completely. Nearly half of the patients were with junior high school or below education level. The main causes of injury were sharp cutting injury and falling injury, the wound duration was 2-365 days, most of the injured parts were limbs and trunk, the wound depth was mostly full-thickness injury, and most patients had wound-related pain and no peculiar smell and used 5 g/L iodophor to clean the wound. Totally 684 (72.1%) patients cleaned their skin after injury, mainly by scrubbing with warm water, the cleaning frequency was mainly once or twice a week, and the cleaning time was mainly 10 or 15 min for each time. Totally 265 (27.9%) patients didn't clean their skin after injury, and the main causes for not cleaning were following the doctor's advice, followed by worrying about wound infection and loss of self-care ability. There were significantly statistical differences in constituent ratios of education level, self-care ability, cause of injury, wound pain, and wound peculiar smell of patients in 2 groups (χ²=12.365, 24.519, 22.820, 9.572, 92.342, P<0.01). Education level, self-care ability, cause of injury, wound pain, and wound peculiar smell were potential influencing factors of skin cleaning in patients. Binary multivariate logistic regression analysis showed that self-care ability, wound pain, and wound peculiar smell were independent influencing factors of skin cleaning in patients (odds ratio=1.51, 0.52, 3.72, 95% confidence interval=1.08-2.12, 0.42-0.89, 2.66-5.22, P<0.05 or P<0.01). Conclusions: Self-care ability, wound pain, and wound peculiar smell are independent influencing factors of skin cleaning in adult trauma patients.

[Application of aMAP score to assess the risk of hepatocarciongenesis in population of chronic liver disease in primary hospitals]

Objective: The aMAP score is a hepatocellular carcinoma (HCC) risk prediction model based on an international cooperative cohort, which can be applied to various liver diseases. The aim of this study is to use the aMAP score to stratify the risk of HCC in patients with chronic liver disease (combined or non-combined metabolic diseases) admitted to People's Hospital of Yudu County, Ganzhou City, Jiangxi Province, in order to guide personalized HCC screening. Methods: The demographic information, laboratory test results (platelets, albumin, and total bilirubin) and combined disease information of patients with chronic liver disease who were admitted to People's Hospital of Yudu from January 2016 to December 2020 were collected, and the aMAP score was calculated to stratify HCC risk in this population. Results: A total of 3629 cases with chronic liver disease were included in the analysis, including 3 452 (95.1%) cases with hepatitis B virus (HBV) infection, 177 (4.9%) cases with fatty liver, and 22 (0.6%) cases with HBV infection and fatty liver. There were 2 679 (73.8%) male and the median age was 44 (35, 54). In the overall population, low, medium and high risk of HCC accounted for 52.6%, 29.0%, and 18.4% respectively. In the HBV-infected population, the proportion of high risk of HCC was significantly higher than that of fatty liver (18.9% vs. 9.6%, P = 0.001). The proportion of chronic liver disease patients with combined hypertension or diabetes was significantly higher than that of those with non-combined metabolic diseases (combined hypertension: 32.3% vs. 17.9%, P < 0.001; combined diabetes: 36.5% vs. 18.1%, P < 0.001). Moreover, the proportion of high-risk population with two metabolic diseases was significantly higher than that with one and no metabolic diseases (40.9% vs. 31.8% vs. 17.7%, P < 0.001). Conclusion: The aMAP score can be used as a simple tool for HCC screening and management of chronic liver disease in primary hospitals, and it is helpful to improve the personalized follow-up management system of chronic liver disease population. Chronic liver disease patients with metabolic diseases have a higher risk of HCC, and people with high risk of HCC should be given special priority in follow-up visits, so as to improve the rate of HCC early diagnosis and reduce the mortality rate.

Effect of congenital heart disease on the recurrence of cough variant asthma in children

Background

The research into the recurrence of cough variant asthma (CVA) in congenital heart disease (CHD) are few in number. The purpose of this study is to investigate the effect of CHD on the risk of the recurrence of CVA.

Methods

This study was a retrospective cohort study of 489 children with CVA aged between one and 14 years, of whom 67 had CHD complicated with CVA and 134 had CVA without CHD at a ratio of 1:2 according to age, sex and index year. The adjusted hazard ratio (aHR) of CVA recurrence in both the CHD cohort and the non-CHD cohort was determined by multivariate analysis using the Cox proportional hazard regression model.

Results

Adjusting for CHD classification, Mycoplasma pneumonia (MP) infection and immunoglobulin E (IgE) sensitization, the recurrence hazard of CVA in the complex congenital heart disease (CCHD) group (aHR = 3.281; 95% CI 1.648–6.530; P < 0.01) was significantly higher than that in the simple congenital heart disease group (aHR = 2.555; 95% CI 1.739–3.752; P < 0.01). Further, children with IgE sensitization (aHR = 2.172; 95% CI 1.482–3.184; P < 0.01) had a higher recurrence hazard of CVA than those without IgE sensitization, and children with MP infection (aHR = 1.777; 95% CI 1.188–2.657; P < 0.01) had a higher recurrence hazard of CVA than those without the MP infection.

Conclusion

The hazard of recurrent CVA is higher in children with CHD, especially in the CCHD children. In addition, those children with IgE sensitization or a MP infection had an increased hazard of recurrent CVA.

[Methodological considerations in the design of clinical trial for innovative hepatitis B drugs]

The research and development of innovative drugs targeting the clinical cure of chronic hepatitis B has become active in recent years. In the clinical trials of new drugs for hepatitis B, the use of new design concepts, new methods, and new technologies to evaluate the efficacy of innovative drugs is expected to shorten the clinical research process of candidate new drugs and reduce the cost of new drug development. However, the new designs such as seamless adaptive design and master plan design have few practical applications in clinical trials of innovative hepatitis B drugs. This article will focus on the methodological factors in the design of phase II/III clinical trials of innovative hepatitis B drugs, and introduce the key points of the new clinical trial design in order to provide methodological references for the development of innovative hepatitis B drugs.

[Expert consensus for diagnosis and treatment of thrombocytopenia in China]

Thrombocytopenia is the main clinical manifestation or common complication of multiple diseases, but there is still a lack of systematic understanding of pathogenesis, underlying diseases and treatment strategies of thrombocytopenia. Based on evidence-based medicine, this consensus summarizes seven aspects related to thrombocytopenia, including definition, epidemiology, pathogenesis, clinical manifestations, laboratory examination, diagnosis and treatment. This consensus provides an important reference for the diagnosis and treatment of thrombocytopenia.

[The phenotypes and genotypes in 314 patients with isolated methylmalonic acidemia]

Objectives: To summarize the clinical and genetic characteristics of the patients with isolated methylmalonic acidemia and investigate the strategies for the diagnosis, treatment and prevention. Methods: Three hundred and fourteen patients (180 males, 134 females) with isolated methylmalonic acidemia were ascertained from 26 provinces or cities across the mainland of China during January 1998 to March 2020. Genetic analysis was performed by Sanger sequencing, gene panel sequencing, whole exome sequencing, multiplex ligation-dependent probe amplification or quantitative PCR. According to the age of onset, the patients were divided to early-onset group (≤12 months of age) and the late-onset group (>12 months of age). They were treated by cobalamin, L-carnitine and (or) special diet and symptomatic treatment. Statistical analysis was done using Chi-square test. Results: Fifty-eight of 314 (18.5%) patients were detected by Newborn screening using liquid chromatography tandem mass spectrometry. Five cases (1.6%) had a postmortem diagnosis. Two hundred and fifty-one patients (79.9%) were clinically diagnosed with an age of onset ranged from 3 hours after birth to 18 years. One hundred and fifty-nine patients (71.0%) belonged to early-onset groups, 65 patients (29.0%) belonged to the late-onset group. The most common symptoms were metabolic crises, psychomotor retardation, epilepsy, anemia and multiple organ damage. Metabolic acidosis and anemia were more common in early-onset patients than that in late-onset patients (20.8%(33/159) vs. 9.2% (6/65), 34.6% (55/159) vs. 16.9% (11/165), χ(2)=4.261, 6.930, P=0.039, 0.008). Genetic tests were performed for 236 patients (75.2%), 96.2%(227/236) had molecular confirmation. One hundred and twenty-seven variants were identified in seven genes (MMUT, MMAA, MMAB, MMADHC, SUCLG1, SUCLA2, and MCEE), of which 49 were novel. The mut type, caused by the deficiency of methylmalonyl-CoA mutase, was the most common (n=211, 93%) cause of this condition. c.729_730insTT, c.1106G>A and c.914T>C were the three most frequent mutations in MMUT gene. The frequency of c.914T>C in early-onset patients was significantly higher than that in late-onset patients (8.3% (18/216) vs. 1.6% (1/64), χ(2)=3.859, P=0.037). Metabolic crisis was more frequent in mut type than the other types (72.6% (114/157) vs. 3/13, χ(2)=13.729, P=0.001),developmental delay and hypotonia were less frequent in mut type (38.2% (60/157) vs. 9/13, 25.5% (40/157) vs. 8/13, χ(2)=4.789, 7.705, P=0.030, 0.006). Of the 58 patients identified by newborn screening, 44 patients (75.9%) who were treated from asymptomatic phase developed normally whereas 14 patients (24.1%) who received treatment after developing symptoms exhibited varying degrees of psychomotor retardation. Conclusions: The characteristics of phenotypes and genotypes among Chinese patients with isolated methylmalonic acidemia were analyzed. Expanded the mutation spectrum of the associated genes. Because of the complex clinical manifestations and severe early onset of isolated methylmalonic acidemia, Newborn screening is crucial for early diagnosis and improvement of prognosis. MMUT gene is recommended for carrier screening as an effort to move the test earlier as a part of the primary prevention of birth defects.

[Clinical value of myositis antibodies in patients with connective tissue disease-associated interstitial lung diseases]

Objective: To investigate the clinical significance of detection of myositis-specific antibodies (MSAs) and myositis-associated antibodies (MAAs) in patients with connective tissue disease-associated interstitial lung diseases (CTD-ILD). Methods: Serum samples of 120 patients with CTD-ILD admitted to the Department of Respiratory, Affiliated Drum Tower Hospital of Nanjing University Medical College from December 2016 to April 2018 were collected for analysis. The patients included 45 with polymyositis/dermatomyositis (PM/DM), 36 with Sjogren's syndrome (SS) and 39 with undifferentiated connective tissue disease (UCTD). There were 37 males and 83 females with an average age of (56±11) years. Thirty-two patients with non-CTD-ILD, 10 males and 22 females with an average age of (42±17) years, were enrolled as the control group. Euroline Autoimmune Inflammatory Myopathies 16 Ag kit was used for detecting MSAs and MAAs, and the positive rates of serum MSAs and MAAs were calculated. The antibody distribution and clinical characteristics of different groups were analyzed and compared. Results: Eighty-nine of the 120 patients with CTD-ILD were positive for MSA and/or MAA (74.2%), and the detection rates of MSAs and MAAs were 52.5% (63/120) and 61.7% (74/120) respectively. No myositis antibody was detected in the non-CTD-ILD group. The detection rates of MSAs in PM/DM-ILD group, SS-ILD group and UCTD-ILD group were 75.6% (34/45), 33.3%(12/36) and 43.6%(17/39) respectively. The total detection rate of MSAs in PM/DM group was significantly higher than that in SS group and UCTD group (χ(2)=14.53, 8.95, 0.01). The anti-ARS was the most frequent (50/120, 41.7%). The positive rates of MAAs in the three groups were 64.4%(29/45), 77.8%(28/36), 43.6%(17/39) respectively, and anti-Ro-52 accounted for 60%(72/120), and were highly correlated with MSAs such as anti-Jo-1 antibodies. Conclusion: Myositis antibody profiling should be performed in patients with ILD who were negative for conventional autoimmune antibody testing and had no CTD. In patients with SS-ILD and UCTD-ILD, the myositis antibody spectrum could detect the presence of myositis-specific antibodies and myositis-related antibodies in some patients, and its role in clinical diagnosis and treatment needed further observation.

Cellular and molecular mechanisms of low dose prolactin potentiation of testicular development in cockerels

The aim of this study was to determine the cellular and molecular mechanisms of prolactin (PRL) in testicular development of prepubertal cockerels. In an in vivo animal experiment, active immunization against PRL severely depressed prepubertal testicular development by significantly reducing testicular weights at both 122 and 164 d of age. The number of elongated spermatids in the seminiferous tubules was also significantly decreased by immunization with 199-residue chicken PRL (cPRL) at age 122 d. Inhibition of testicular development by cPRL immunization was associated with decreases in LH receptor (LHR), FSH receptor (FSHR), Stat5b, P450scc, steroidogenic acute regulatory (StAR) protein, and 3β-hydroxysteroid dehydrogenase (3β-HSD) mRNA expression levels in testicular tissue. In in vitro experiments, testosterone production by cultured Leydig cells isolated from prepubertal cockerel testes was dose-dependently enhanced by treatment with bioactive recombinant PRL, but a lesser response was seen with high concentrations of PRL. The distinct changes in testosterone production in response to high and low concentrations of added PRL were paralleled by similar patterns of change in the mRNA levels of Stat5b, LHR, P450scc, StAR, 3β-HSD, and CYP17A1 in cultured Leydig cells, as well as protein amounts of phosphorylated Jak2 and Stat5a/b. In conclusion, low to medium doses of PRL potentiate testis development in prepubertal cockerels by enhancing testosterone secretion from Leydig cells via activation of PRLR/Stat5b signal transduction, which upregulates mRNA expression of LHR and testosterone synthesizing enzymes. However, this positive regulation was weaker in response to a high dose of PRL, which reduced PRLR/Stat5b signal transduction and the expression of genes involved in LH signaling and testosterone synthesis.

[Effects of loupes and microscope on laminate veneer preparation]

OBJECTIVE

To assess and compare the effects of loupes and microscope on laminate veneer preparation of the first practitioner from the aspects of efficiency, quality and accuracy of preparation, and preference.

METHODS

Twenty young prosthodontists from the Department of Prosthodontics, Peking University School and Hospital of Stomatology were recruited into this study, which was prospective, single blind, self-control trials. The participants had no experience of using dental magnification devices. They prepared laminate veneers in the artificial dental model, under routine visual field (control group), 2.5× headwear loupes (loupes group), and 8× operating microscope (microscopic group) by turning. The time for tooth preparation was recorded. Thereafter, subjective assessments of efficiency, quality of preparation and preference were performed by themselves using visual analogue score (VAS). Expert assessments of quality and accuracy of preparation were performed by two professors using stereomicroscope and digital technique respectively.

RESULTS

In terms of efficiency, the subjective scores for the control group, loupes group and microscopic group were 7.15±1.73, 8.10±0.91 and 5.40±2.04, respectively. There was significant difference between the loupes group and microscopic group (P<0.05). The time of tooth preparation for the control group, loupes group and microscopic group was (430.10±163.04) s, (393.90±157.27) s and (441.95±164.18) s, respectively. There was significant difference between the loupes group and microscopic group (P<0.05). The loupes group was more efficient than the microscopic group. In terms of the quality of preparations, the subjective scores for the control group, loupes group and microscopic group were 6.55±2.09, 7.85±0.99 and 6.25±1.77, respectively. There was significant difference between the loupes group and microscopic group (P<0.05). The expert evaluations for the control group, loupes group and microscopic group were 12.20±1.67, 12.50±1.70 and 11.35±2.60, respectively. There was significant difference between the loupes group and microscopic group (P<0.05). The loupes group had higher quality than the microscopic group. In terms of the accuracy of preparations, the control group, loupes group and microscopic group of incisal 1/3 were (0.107±0.097) mm, (0.142±0.118) mm and (0.123±0.087) mm, respectively, of middle 1/3 were (0.128±0.073) mm, (0.113±0.105) mm and (0.125±0.077) mm, respectively, and of cervical 1/3 were (0.075±0.054) mm, (0.068±0.044) mm and (0.058±0.047) mm, respectively. There was no significant difference among the three groups (P>0.05). In terms of the preference, the subjective scores for the control group, loupes group and microscopic group were 6.55±2.31, 8.60±1.10 and 5.80±2.07, respectively. There was significant difference between the loupes group and microscopic group (P<0.05). The participants had the highest preference for loupes.

CONCLUSION

For the first practitioners, loupes is better than microscope for laminate veneer preparation.

[Oral hygiene maintenance of locator attachments implant overdentures in edentulous population: A longitudinal study]

OBJECTIVE

To investigate the oral hygiene status of edentulous patients with locator attachments implant overdentures (IOD) and to analyze the relationship among daily hygiene behavior, oral hygiene status and peri-implant diseases.

METHODS

Edentulous patients who received IOD treatment with locator attachments from January 2012 to May 2016 were recruited. Clinical and radiographic examinations were conducted to assess the peri-implant tissue status. Modified plaque index (mPLI), sulcus bleeding index (SBI), gingival index (GI), and probing depth (PD) were recorded and peri-implant marginal bone loss (MBL) was measured using paralleling projection technique. Patients' peri-implant oral hygiene maintainence habits were investigated. The correlation between peri-implant diseases and oral hygiene status and behaviors was analyzed.

RESULTS

Fifty patients (125 implants) with an average follow-up time of 22 months (6-54 months) were enrolled. The mean values of mPLI, SBI, and GI were 1.4±1.2, 0.8±0.7, and 0.7± 0.6, respectively. Average PD was (2.2±0.7) mm. Mesial and distal maginal bone resorptions were (1.1±1.1) mm and (0.9±0.9) mm, respectively. The prevalance of mucositis and peri-implantitis of the implants were 49.6% and 0. The prevelance of mucositis in the patients with poor oral hygiene (mPLI≥2) was 11.9 times as much as that of those with adequate oral hygiene (mPLI<1). The patients who performed oral hygiene procedure on attachments at least twice a day achieved much lower mPLI scores than those who cleaned less than twice a day.

CONCLUSION

Oral hygiene condition in the group of patients with implant overdentures was poor, and it contributed to increased risk of peri-implant mucositis. The prevelance of musositis of the paitients with poor oral hygiene was 11.9 times as much as that of those with proper oral hygiene. Patients wearing IOD should pay more attention to the hygiene of the attachments.

[One case of refractory gout with high fever]

On 17th June 2017, a 50 years old man with refractory gout was admitted in our hospital. During the treatment, he was accompanied by intermittent fever (39 to 40 ℃) of unknown origin for 60 days and gastrointestinal bleeding, with difficult wound repair. After comprehensive treatment of thorough debridement, vacuum sealing drainage, skin graft, skin flap repair, and drug administration, the patient was discharged fully recovered on post hospitalization day 104.

[Genetic diagnosis of Caroli syndrome with autosomal recessive polycystic kidney disease: a case report and literature review]

This case report is about one genetically specified diagnosed infant case of Caroli syndrome with autosomal recessive polycystic kidney disease (ARPKD) in China. The patient in this case report was an eight-month infant boy with an atypical onset and the main clinical manifestation was non-symptomatic enlargement of the liver and kidneys. The imaging study demonstrated a diffused cystic dilatation of intrahepatic bile ducts as well as polycystic changes in bilateral kidneys. The basic blood biochemical tests indicated a normal hepatorenal function. Four serum biomarkers of hepatic fibrosis were all elevated and the urine test for an early detection of the renal injury was positive. The genetic sequencing proved two heterozygous missense mutations of polycystic kidney and hepatic disease 1 (PKHD1) gene, c.9292G>A and c.2507T>C, inherited from each of his parents respectively. The former was a novel mutation that had been verified as disease causing through the predicting software while the latter had been reported from one recent case study on Chinese twins, which was possibly unique among Chinese population. The relations between the gene type and the clinical phenotype were not clarified yet. Up till a follow-up eleven months later after the discharge, the patient had a normal hepatorenal function without occurrence of any severe complication yet. The clinical symptoms of Caroli syndrome with ARPKD at infant stage were atypical and the enlargement of liver and kidney was usually the sole symptom. From the above systematic retrospective clinical analysis, as well as the relevant literature review, it's been concluded that the features of the hepatorenal images in patients with Caroli syndrome and ARPKD were distinctive. Genetic testing combined with the imaging study benefits a definite diagnosis as well as a differentiation from other hepatorenal fibrocystic diseases. Specific to the long-term management of this kind of patients, it's necessary to schedule a regular follow-up to monitor the hepatorenal function and the occurrence of various complications for an appropriate intervention, meantime to devote efforts to the genetic counseling work for the patients' family.

[Relationship between overnight urinary sodium to potassium ratio and the risk of cardiovascular disease]

Objective: To explore the relationship between overnight urinary sodium to potassium ratio and the risk of cardiovascular disease (CVD). Methods: A subsample of 10 percent of the participants (35-59 years old) from the People's Republic of China-United States Collaborative Study of Cardiovascular and Cardiopulmonary Epidemiology (prospective survey) were used. Three consecutive overnight urine samples were collected in the autumn of 1983-1984 and the spring in 1985-1986, respectively. Urinary sodium and potassium were detected and calculated for 8 hours excretion. The occurrences of cardiovascular events were recorded in 2 years interval from 1987-1988 until December 31, 2005. Participants were divided into first ratio group, second ratio group, and third ratio group based on the tertiles of sodium to potassium ratio. Cox proportional hazard regression model was used to determine the relationship between sodium to potassium ratio and risk of CVD. In addition, participants were divided into 2 subgroups by the median of overnight urinary sodium and potassium, and then combined each other for 4 subgroups including low sodium-low potassium group, low sodium-high potassium group, high sodium-low potassium group, and high sodium-high potassium group, to explore the relationship between different sodium-potassium combinations and the risk of CVD. Results: A total of 954 participants were included in the final analysis, of whom 459 (48.1%) were males. There were 318 cases in the first, second and third ratio group, respectively. There were 347 cases in low sodium-low potassium group and high sodium-high potassium group, and 130 cases in low sodium-high potassium group and high sodium-low potassium group. After a median follow-up of 18.6 (18.3, 19.3) years, cardiovascular events occurred in 81 participants, including 64 stroke and 20 coronary heart disease events. Multivariate analysis showed that comparing with the first ratio group, the hazard ratios (HR) in the second and the third ratio groups were 2.04 (95%CI 1.06-3.95, P=0.034) and 2.07 (95%CI 1.07-4.03, P=0.032), respectively. The CVD risk in low sodium-low potassium group was 24% higher than the low sodium-high potassium group (reference), but this result did not reach statistical significant level (P=0.685). The risks in high sodium-high potassium group (HR=3.32, 95%CI 1.26-8.76,P=0.015) and high sodium-low potassium (HR=3.04, 95%CI 1.05-8.83, P=0.041) group were both significantly increased. Conclusions: Overnight urinary sodium to potassium ratio is positively correlated with the risk of cardiovascular events. High urinary sodium plays a more important role for the increased risk of cardiovascular events than low potassium.

[Effects of different surface treatments on the zirconia-resin cement bond strength]

OBJECTIVE

To evaluate the effects of different surface treatments on the shear bond strength between zirconia and resin cement.

METHODS

Forty zirconia discs were randomly divided into four groups (10 discs in each group) for different surface treatments: control, no surface treatment; sandblast, applied air abrasion with aluminum oxide particles; ultraviolet (UV), the zirconia sample was placed in the UV sterilizer at the bottom of the UV lamp at 10 mm, and irradiated for 48 h; cold plasma, the discs were put in the cold plasma cabinet with the cold plasma generated from the gas of He for 30 s. Specimens of all the groups were surface treated prior to cementation with Panavia F 2.0 cement. The surface morphology and contact angle of water were measured. The shear bond strengths were tested and the failure modes were examined with a stereomicroscope.

RESULTS

Surface morphology showed no difference between the UV/cold plasma group and the control group. Sandblasted zirconia displayed an overall heterogeneous distribution of micropores. The contact angle of the control group was 64.1°±2.0°. After sandblasting, UV irradiation and cold plasma exposure, the values significantly decreased to 48.8°±2.6°, 27.1°±3.6° and 32.0°±3.3°. The values of shear bond strength of the specimens with sandblasted (14.82±2.01) MPa were higher than those with no treatment (9.41±1.07) MPa with statistically significant difference (P<0.05). The values of shear bond strength of the specimens with UV irradiation (10.02±0.64) MPa were higher than those with no treatment (9.41±1.07) MPa, but without statistically significant difference (P>0.05). The values of cold plasma group (18.34±3.05) MPa were significantly higher than those of control group (9.41±1.07) MPa, even more than those with sandblast(14.82±2.01) MPa (P<0.05). X-ray photoelectron spectroscopy (XPS) showed increase in oxygen (O) and decrease in carbon (C) elements after UV and cold plasma treatment. The surface C/O ratio also decreased after UV and cold plasma treatment.

CONCLUSION

Zirconia specimens treated with UV and cold plasma could significantly improve the hydrophilicity. The surface morphology was unaffected by the UV irradiation and cold plasma treatments. The improvements of ziconia shear bond strength were slight in UV group without statistically significant difference. Cold plasma treatment significantly improved the shear bond strength between zirconia and resin cement.

CoO microspheres and metallic Co evolved from hexagonal α-Co(OH)2 plates in a hydrothermal process for lithium storage and magnetic applications

CoO microspheres and metallic Co could be successfully synthesized by simply reacting cobalt acetate with a mixture solvent of ethylene glycol and deionized water in a hydrothermal process for different times. As the reaction proceeded, α-Co(OH)₂, CoO and metallic Co were produced. To understand the phase evolution processes from α-Co(OH)₂ to CoO and then metallic Co, a range of time-dependent experiments were carried out, and the intermediate products obtained at different reaction times were investigated in detail. The investigation revealed that CoO microspheres were actually evolved from α-Co(OH)₂ as a precursor. Just elongating the reaction time, CoO microspheres could be further reduced to metallic Co. With a pure ethylene glycol medium for the same reaction, only α-Co(OH)₂ could be generated, indicating an important role of water. When the obtained CoO microspheres were used as anode materials for lithium-ion batteries, they delivered a specific capacity of 803 mA h g^-1 at 0.1 A g^-1 with a retention of 453 mA h g^-1 after 70 cycles. Meanwhile, the magnetic properties of the obtained CoO microspheres and metallic Co were investigated, with the CoO microspheres showing an antiferromagnetic behavior and the metallic Co exhibiting ferromagnetic characteristics. This study suggested a novel method for synthesizing CoO with a uniform microsphere morphology and bulk metallic Co easily.

Electric field tuned MoS2/metal interface for hydrogen evolution catalyst from first-principles investigations

Understanding the interfacial properties of catalyst/substrate is crucial for the design of high-performance catalyst for important chemical reactions. Recent years have witnessed a surge of research in utilizing MoS₂ as a promising electro-catalyst for hydrogen production, and field effect has been employed to enhance the activity (Wang et al 2017 Adv. Mater. 29, 1604464; Yan et al 2017 Nano Lett. 17, 4109-15). However, the underlying atomic mechanism remains unclear. In this paper, by using the prototype MoS₂/Au system as a probe, we investigate effects of external electric field on the interfacial electronic structures via density functional theory (DFT) based first-principles calculations. Our results reveal that although there is no covalent interaction between MoS₂ overlayer and Au substrate, an applied electric field efficiently adjusts the charge transfer between MoS₂ and Au, leading to tunable Schottky barrier type (n-type to p-type) and decrease of barrier height to facilitate charge injection. Furthermore, we predict that the adsorption energy of atomic hydrogen on MoS₂/Au to be readily controlled by electric field to a broad range within a modest magnitude of field, which may benefit the performance enhancement of hydrogen evolution reaction. Our DFT results provide valuable insight into the experimental observations and pave the way for future understanding and control of catalysts in practice, such as those with vacancies, defects, edge states or synthesized nanostructures.

[Value of two left atrium and pulmonary vein stereoscopic imaging reconstruction methods on guiding radiofrequency ablation for atrial fibrillation]

Objective: To compare the value of two 3D imaging reconstruction methods for left atria and pulmonary vein on guiding the catheter ablation for atrial fibrillation (AF). Methods: From January 2014 to January 2017, a total of 100 drug refractory paroxysmal AF patients were divided into left atria direct angiography group (n=50), and indirect angiography group (n=50). 3D CARTO system was applied for mapping and guiding the ablation procedure. Patients assigned to direct angiography group were treated as follows: intraoperative puncture of atrial septum, inject contrast agent directly into the left atrium, conduct left atrial and pulmonary venous rotation angiography, reconstruct three-dimensional image, integrate the image into real-time X-ray system to facilitate circumferential pulmonary vein isolation. Patients assigned into the indirect angiography group were treated as follows: inject contrast agent through the right ventricle, conduct delayed rotation angiography of the left atria and pulmonary vein to guide circumferential pulmonary vein fixation and ablation. The left atrial and pulmonary venous image acquisition, the operation and X-ray exposure time, the success rate and the incidence of complication of the two groups were compared. The patients were followed up for 3-6 months. Results: General clinical characteristics of the two groups were similar(all P>0.05). Ablation was successful in all 100 patients. The operation time[(112.0±21.4)min vs. (134.0±24.3)min]and X-ray exposure time((10.7±4.7)min vs. (15.8±5.2)min)were significantly lower in direct angiography group than in indirect angiography group (both P<0.01). There was no significant difference between the two groups in the immediate (86%(43/50) vs. 82%(41/50), P=0.59) and short-term (76%(38/50) vs. 72%(36/50), P=0.65) success rate and complication rate (1 aneurysm in the direct angiography group, 1 pericardial tamponade in the indirect angiography group). In-hospital mortality was zero percent. Conclusion: It is safe and effective method to guide the radiofrequency catheter ablation of paroxysmal atrial fibrillation by reconstruction 3D image of left atrium and pulmonary vein. Compared with indirect angiography group, direct angiography group can improve the imaging quality of left atrium and pulmonary vein, decrease the X-ray exposure time of the ablation procedure.

[Pulmonary arterial hypertension as leading manifestation of methylmalonic aciduria: clinical characteristics and gene testing in 15 cases]

OBJECTIVE

To deepen our understanding of Methylmalonic aciduria (MMA) associated pulmonary hypertension (PH) by analyzing the characteristics of clinical presentation, pulmonary high resolusion CT(HRCT), treatment response and gene mutation.

METHODS

This study includes 15 cases of pediatric patients with MMA associated PH diagnosed and treated in Peking University First Hospital pediatric department between May 2012 and May 2016 with symptoms of PH as their leading presentation. Clinical symptoms and signs were recorded, Routine blood laboratory examinations was done including arterial blood gas analysis. Plasma total homocysteine (Hcy) and brain natriuretic peptide(BNP) level were measured. MMA gene mutation was analyzed. Chest HRCT was done in most of the patients. Standard treatment strategy to MMA and PH was given and follow up study was done, and the related literature was reviewed. Statistical analysis was done. The diagnosis of MMA was made by methylmalonic acid level >100 times the normal value in the urine. The diagnosis of PH was made by pulmonary arterial systolic pressure (PASP)>40 mmHg, which was estimated by the measurement of tricuspid regurgitation velocity through Doppler Echocardiography.

RESULTS

(1) Patient characteristics: There were 10 male and 5 female patients diagnosed as MMA associated PH, aged 0.5 to 13.8 years, with an average of (5.0±4.3) years. The age of onset of PH was (3.7±3.5) years, with an early onset type MMA in 5 cases and late-onset type in 10 cases. (2) Clinical presentation: Among the 15 cases of MMA, the first symptoms were associated with PH in 10 cases, so PH and MMA were diagnosed at the same time, and PH was diagnosed 3 to 72 months post MMA presentation in the other 5 cases. The main presentations of PH were techypnea/dyspnea and cyanosis in 11 cases each, weakness and fatigue on exertion in 6 cases, and edema in 4 cases. PH WHO functional classification (WHO FC) was Class II in 4 , Class III in 5 and Class VI in 6 cases, with an average of Class 3.1±0.8. Multi-system involvements were common with the highest frequency in the kidney (14 cases). Macrocytic anemia was present in 8 cases and sub-clinical hypothyroidism in 5 cases, and mild to moderate mental retardation in 4 cases. (3) Laboratory examination: PASP of the 15 patients was from 49 to 135 mmHg, with an average of (90.3±23.9) mmHg. Total blood Hcy level was severely elevated to (121.2±48.2) μmol/L (range: 35.0-221.0 μmol/L), and Hcy >100 μmol/L within 11 cases. Plasma BNP level was also elevated, median 794 ng/L (range: 21.0-4 995.0 ng/L) with 12 cases >300 ng/L. Blood gas analysis showed low arterial blood oxygen saturation between 70% and 94%, with an average of 81.4%±8.4%. (4) Chest HRCT: chest HRCT showed a diffuse ground-glass centrilobular nodular opacities with septal line thickening in the lungs in 9 cases, and with associated mediastinal lymph node enlargement in 1 case, which indicated pulmonary veno-occlusive disease (PVOD), a rare type of pulmonary arterial hypertension (PAH). There was lung infection or edema in 3 cases, and interstitial infiltration and mesh-like feature in other 3 cases, which was inferred to interstitial lung disease. (5) Gene mutation: Genetic testing was done in 10 cases, totally 5 reported disease-causing mutations were found. There were 100% presence of MMACHC c.80A>G mutation in all the 10 patients tested, with the allelic genes of c.609G>A mutation in 6 patients, including a sister and a brother from the same parents. (6) Treatment and follow up: Intramuscular hydroxocobalamin or vitamin B12 was given to all of the patients, together with betaine, levocarnidtine, folinic acid and vitamin B6. According to the severity of PH, single or combined PAH targeted drugs was given to 11 cases. By an average of (20.0±13.5) days of in-hospital treatment in 13 patients (excepting 1 case treated as outpatient), symptoms remarkably resolved, WHO FC reduced to an average of Class 2.4±0.9, PASP dropped to (69.4±21.3) mmHg, and plasma Hcy and BNP level were decreased to (74.9±25.9) μmol/L and (341.6±180.2) ng/L, respectively. The above values all reached statistical significance (P<0.05) compared with each related value before treatment. There were 2 patients who expired during hospitalization despite of treatment. At the end of 3 months' follow up, all of the 13 patients disposed oxygen, and PASP significantly dropped to 38.7±7.9 mmHg, and plasma BNP returned to normal, but plasma Hcy level showed no further decline. At the last follow up of 27.5±19.0 (range: 11-64) months, all the patients' PASP remained normal except for the 13.8-year-old boy with 6 years-long history of MMA and almost 3.6 years' history of PH still having PASP 58 mmHg.

CONCLUSION

PH is a severe complication of MMA combined type, especially cblC type, it is more often happens in late-onset type of male patients and can be the first and leading manifestations of MMA. Its clinical symptoms are urgent and severe, characterized by tachypnea/dyspnea and cyanosis, and sometimes right heart failure, hypoxemia is usually present, chest HRCT is often indicative of PVOD, lung edema and interstitial lung disease may occur. Rapid diagnosis and targeted treatment of MMA with appropriate anti-PAH medication can reverse PH and save life. MMACHC gene c.80A>G mutation may be the hot point of MMA cblC type associated PH.

First-line icotinib versus cisplatin/pemetrexed plus pemetrexed maintenance therapy for patients with advanced EGFR mutation-positive lung adenocarcinoma (CONVINCE): a phase 3, open-label, randomized study

BACKGROUND

Icotinib has been previously shown to be non-inferior to gefitinib in non-selected advanced non-small-cell lung cancer patients when given as second- or further-line treatment. In this open-label, randomized, phase 3 CONVINCE trial, we assessed the efficacy and safety of first-line icotinib versus cisplatin/pemetrexed plus pemetrexed maintenance in lung adenocarcinoma patients with epidermal growth factor receptor (EGFR) mutation.

PATIENTS AND METHODS

Eligible participants were adults with stage IIIB/IV lung adenocarcinoma and exon 19/21 EGFR mutations. Participants were randomly allocated (1 : 1) to receive oral icotinib or 3-week cycle of cisplatin plus pemetrexed for up to four cycles; non-progressive patients after four cycles were maintained with pemetrexed until disease progression or intolerable toxicity. The primary end point was progression-free survival (PFS) assessed by independent response evaluation committee. Other end points included overall survival (OS) and safety.

RESULTS

Between January 2013 and August 2014, 296 patients were randomized, and 285 patients were treated (148 to icotinib, 137 to chemotherapy). Independent response evaluation committee-assessed PFS was significantly longer in the icotinib group (11.2 versus 7.9 months; hazard ratio, 0.61, 95% confidence interval 0.43-0.87; P = 0.006). No significant difference for OS was observed between treatments in the overall population or in EGFR-mutated subgroups (exon 19 Del/21 L858R). The most common grade 3 or 4 adverse events (AEs) in the icotinib group were rash (14.8%) and diarrhea (7.4%), compared with nausea (45.9%), vomiting (29.2%), and neutropenia (10.9%) in the chemotherapy group. AEs (79.1% versus 94.2%; P < 0.001) and treatment-related AEs (54.1% versus 90.5%; P < 0.001) were significantly fewer in the icotinib group than in the chemotherapy group.

CONCLUSIONS

First-line icotinib significantly improves PFS of advanced lung adenocarcinoma patients with EGFR mutation with a tolerable and manageable safety profile. Icotinib should be considered as a first-line treatment for this patient population.

[Nested case-control study on associated factors for anemia during pregnancy]

Objective: To explore the related factors of anemia during pregnancy and provide scientific evidence for the primary prevention of anemia during pregnancy. Methods: The pregnant women (≤12 pregnant weeks) who received the first pregnancy care in a local medical institution in Hunan province from June 2013 to November 2014 were included in this cohort study, and for them anemia had been excluded by physical examination. Baseline survey and follow up till childbirth were conducted for them. A queue-based nested case-control study (1 ∶ 2) was conducted (380 pregnant women with anemia detected in this study as case group, 760 pregnant women without anemia randomly selected and matched by age, habitual residence during pregnancy as control group. And t test, χ(2) test and logistic regression analysis were conducted to identify related factors of anemia during pregnancy. Results: Multivariate logistic regression analysis indicated that low family annual income level (net income) (OR=2.08, 95%CI: 1.22-3.59), low educational level (OR=2.09, 95%CI: 1.22-3.59), pre-pregnancy perm/hair dye (OR=2.23, 95%CI: 1.63-3.05), early pregnancy vomiting (OR=2.51, 95%CI: 1.56-4.03) were the risk factors for anemia during pregnancy. Intake of vitamin and trace element supplements (OR=0.69, 95%CI: 0.50-0.94), frequent meat, fish, shrimp, egg intakes (OR=0.68, 95%CI: 0.49-0.92), frequent soy milk, milk intakes (OR=0.51, 95%CI: 0.27-0.95) were the protective factors for anemia during pregnancy. Conclusion: A number of factors, such as family annual income level, education level, poisonous and harmful material contact, pregnancy reaction, nutrition, are related to the incidence of anemia during pregnancy, it is necessary to take preventive measures to reduce the incidence of anemia during pregnancy.

[Multicenter investigation of the correlation between supraventricular tachycardia and tachycardia-induced cardiomyopathy in children]

Objective: This study aimed to investigate the correlation between supraventricular tachycardia (SVT) and tachycardia-induced cardiomyopathy(TIC) in children and assess the risk factors for the development of TIC. Method: One hundred and eighty-three patients were recruited in four hospitals of Beijing diagnosed as SVT were divided into two groups depending on whether or not complicated with TIC. The age, gender, tachycardia type, ventricular rate during tachycardia, frequency of tachycardia episodes and duration of tachycardia were compared between the two groups and risk factors associated with TIC were analyzed. Statistical analyses were performed using t test, Mann-Whitney U and χ(2) test. Result: Totally 183 patients were included in this study (paroxysmal supraventricular tachycardia, PSVT, n=149; atrial tachycardia, AT, n=34). The incidence of TIC was 13.1%. There was significant difference regarding the incidence of TIC between children with AT and children with PSVT (26.5% vs. 10.1%, χ(2)=6.537, P=0.011). The percentage of AT in patients with TIC was significantly higher than patients without TIC (37.5% vs. 15.7%, χ(2)=6.537, P=0.011). Patients with TIC had a higher frequency of tachycardia episodes(2.5(1.0-4.8) beats/year vs 4.0(1.0-10.0) beats/year, Z=-2.223, P=0.026)and longer duration of tachycardia(11.0(1.1-36.0) h vs 2.5(1.0-12.0) h, Z=-2.154, P=0.031)compared with patients without TIC. Multivariate predictors of TIC was longer duration of tachycardia (OR=2.041, P=0.028). Conclusion: TIC occurs in 13.1% of children with SVT. The incidence of TIC in children with AT is higher than in children with PSVT. Risk factor for the development of TIC is longer duration of tachycardia.

Development and characterization of microsatellite markers for Solen grandis using Illumina sequencing approach

Solen grandis is an important economic and overexploited bivalve species. In order to perform its fine-scale genetic analyses, 105 pairs of microsatellites with polymorphism were identified through Illumina Hiseq platform and bioinformatic assembly technology in this study. The estimated fragment size ranged from 100 to 268 bp and the number of alleles per locus varied between 2 and 23. Observed and expected heterozygosities varied from 0.0667 to 1.0000 and 0.0966 to 0.9492, respectively. Fourteen loci deviated significantly from Hardy-Weinberg equilibrium after Bonferroni correction. These microsatellite markers developed in this study would be helpful for future genetic studies on S. grandis and closely related species.

[Application of SAS macro to evaluated multiplicative and additive interaction in logistic and Cox regression in clinical practices]

Conditional logistic regression analysis and unconditional logistic regression analysis are commonly used in case control study, but Cox proportional hazard model is often used in survival data analysis. Most literature only refer to main effect model, however, generalized linear model differs from general linear model, and the interaction was composed of multiplicative interaction and additive interaction. The former is only statistical significant, but the latter has biological significance. In this paper, macros was written by using SAS 9.4 and the contrast ratio, attributable proportion due to interaction and synergy index were calculated while calculating the items of logistic and Cox regression interactions, and the confidence intervals of Wald, delta and profile likelihood were used to evaluate additive interaction for the reference in big data analysis in clinical epidemiology and in analysis of genetic multiplicative and additive interactions.

[Expression and significance of miR-210 in the epididymis in rats with varicocele and following varicocelectomy]

Objective: To investigate the expression of microRNA 210 (miR-210) in the epididymis of rats with varicocele and changes in miR-210 expression following high spermatic vein ligation, so as to explore the significance of the surgery in treating varicocele. Methods: A total of 21 male Sprague-Dawley (SD) rats aged 7 weeks were randomly divided into control group (n=7), experimental group (n=7), and surgical group (n=7). Varicocele model was established in both the experimental and surgical groups, while only vein isolation was performed in the control group. After 8 weeks, spermatic vein diameter were measured in the control and experimental rats, and collected the left epididymis (fixed in formaldehyde and frozen in refrigerator at -80 ℃). In the surgical group, left high spermatic vein ligation was performed, and the left epididymis was collected after 4 weeks as in the control and the experimental groups. The fixed epididymis tissues were treated with HE staining for observation of tissue injuries. The miR-210 expression in the epididymis was detected with reverse transcription-polymerase chain reaction (RT-PCR). At last every group had 5 rats. Results: The pathological examination showed that the number and distribution of mature sperms in epididymal duct in the experimental group were lower and less even compared to the control group, while the two indicators in the surgical group were better than those in the experimental group. The diameter of the left spermatic vein in the experimental group and pre-treatment surgical group were significantly enlarged than in the control group (P<0.01). The expression of miR-210 in the left epididymis in the experimental group was significantly higher compared with the control group(1.32±0.06 vs 0.98±0.14, P<0.01), while the expression of miR-210 in the left epididymis in the surgical group was significantly decreased compared with the experimental group (0.96±0.16 vs 1.32±0.06, P<0.01); the difference between the control group and the surgical group was not statistically significant (P>0.05). Conclusion: The expression of miR-210 in the epididymis may be increased by varicocele and reduced after high ligation of the affected spermatic vein.

Invasive pulmonary fungal infections in patients with connective tissue disease: a retrospective study from northern China

Invasive pulmonary fungal infection (IPFI) is a potentially fatal complication in patients with connective tissue disease (CTD). The current study aimed to uncover the clinical characteristics and risk factors of patients with IPFI-CTD. The files of 2186 CTD patients admitted to a single center in northern China between January 2011 and December 2013 were retrospectively reviewed. A total of 47 CTD patients with IPFI were enrolled into this study and assigned to the CTD-IPFI group, while 47 uninfected CTD patients were assigned to the control group. Clinical manifestations were recorded, and risk factors of IPFI were calculated by stepwise logistical regression analysis. Forty-seven (2.15%) CTD patients developed IPFI. Systemic lupus erythematosus patients were responsible for the highest proportion (36.17%) of cases with IPFI. Candida albicans (72.3%) accounted for the most common fungal species. CTD-IPFI patients had significantly elevated white blood cell count, erythrocyte sedimentation rate, C-reactive protein and fasting glucose values compared to controls (P<0.05). Cough, sputum and blood in phlegm were the most common symptoms. Risk factors of IPFI in CTD included maximum prednisone dose ≥30 mg/day within 3 months prior to infection, anti-microbial drug therapy, and interstitial pneumonia. CTD patients who have underlying interstitial pneumonia, prior prednisone or multiple antibiotics, were more likely to develop IPFI.

[Spontaneous intracranial hypotension: 12 case reports and follow-up]

Objective: To investigate the pathogenesis, clinical presentation, imaging features and prognosis of spontaneous intracranial hypotension. Methods: Clinical manifestation and imaging changes of 12 patients with spontaneous intracranial hypotension were reported. They were followed up regularly. The clinical and neuroimaging characteristics were summarized. Results: All the 12 cases were adults, presenting with orthostatic headache. They all recovered with conservative therapy. Head MRI demonstrated cerebral lobe hemorrhage, subdural hematoma, pituitary hyperemia, subarachnoid hemorrhage, enhancement of the pachymeninges, sagging of the brain, etc. Conclusions: Spontaneous intracranial hypotension is characterized by orthostatic headaches and is associated with compensatory changes following loss of CSF volume. The long-time prognosis is not bad.

A touchdown multiplex PCR for porcine circovirus type 2 and pseudorabies virus

KEYWORDS

porcine circovirus type 2; pseudorabies virus; conventional multiplex PCR; touchdown multiplex PCR.