[Analysis on personal protection in occupational population at high risk for brucellosis and influencing factor in China]

Objective: To understand the current status of personal protection in occupational population at high risk for brucellosis in China and provide evidence for the evaluation of implementation of National Brucellosis Prevention and Control Plan (2016-2020). Methods: Four counties in Shanxi Province and Xinjiang Uygur Autonomous Region were selected to conduct a questionnaire survey in occupational population at high risk for brucellosis from December 2019 to July 2020 by using cross-sectional survey methods. Results: A total of 2 384 persons at high risk for brucellosis were surveyed, and the standardized utilization rate of personal protective equipment (PPE) was 20.13% (480/2 384). The utilization rate of glove, mask, rubber shoe, and work cloth were 38.26% (912/2 384), 31.80% (758/2 384), 32.01% (763/2 384) and 30.87% (736/2 384),respectively. There were significant differences in the utilization rate and standardized utilization rate of the four types of PPE among populations in different age, occupation, educational level and area groups (all P<0.001). The utilization rate and standardized utilization rate of PPE were lower in people over 60 years old, women, farmers, and those with lower educational level. The results of multivariate analysis showed that occupation and area were the influencing factors for the standardized utilization of PPE, the standardized utilization rates of PPE were higher in herdsmen and veterinarians. The standardized utilization rate of PPE in Yanggao County and Huocheng County was significantly higher than that in Zuoyun County and Hunyuan County. Conclusions: The utilization rate of the four types of PPE in occupational population at high risk for brucellosis was not high in China, and the standardized utilization rate was low, lower than the requirement in National Brucellosis Prevention and Control Plan, and there were significant differences among different areas. It is urgent to distribute PPE to occupational population at high risk for brucellosis and carry out health education about PPE utilization. Meanwhile, it is necessary to strengthen information exchange or sharing among different areas.

[New progress in the first-line treatment of advanced hepatocellular carcinoma]

Hepatocellular carcinoma is a kind of cancer with a strong invasion, a high incidence rate and mortality, and a poor prognosis. At the time of diagnosis, most patients are already in the advanced stages of a tumor and have lost the chance for radical surgical treatment. Advanced hepatocellular carcinoma treatment has a gradual transition from systemic chemotherapy to targeted therapy, immunotherapy, and combination therapy, especially immune checkpoint inhibitor-based immunotherapy combination therapy, such as combination with bevacizumab monoclonal antibodies and other drugs, or combination with TACE, HAIC, radiotherapy, ablation, and other treatment methods. Combination therapy has significant synergistic effects and thus has already become a future treatment trend for hepatocellular carcinoma. An immunotherapy-based combination therapy plan will run through the whole process of systemic therapy, which is expected to bring better survival benefits to patients with hepatocellular carcinoma. This article reviews the latest research progress in aspects of the first-line treatment of advanced hepatocellular carcinoma.

[Clinical analysis of 10 cases of multi-center tumor necrosis factor receptor-associated periodic syndrome]

Objective: To summarize the clinical characteristics of tumour necrosis factor receptor-associated periodic syndrome (TRAPS) in children. Methods: The clinical manifestations, laboratory tests, genetic testing and follow-up of 10 children with TRAPS from May 2011 to May 2021 in 6 hospitals in China were retrospectively analyzed. Results: Among the 10 patients with TRAPS, including 8 boys and 2 girls. The age of onset was 2 (1, 5) years, the age of diagnosis was (8±4) years, and the time from onset to diagnosis was 3 (1, 7) years. A total of 7 types of TNFRSF1A gene variants were detected, including 5 paternal variations, 1 maternal variation and 4 de novo variations. Six children had a family history of related diseases. Clinical manifestations included recurrent fever in 10 cases, rash in 4 cases, abdominal pain in 6 cases, joint involvement in 6 cases, periorbital edema in 1 case, and myalgia in 4 cases. Two patients had hematological system involvement. The erythrocyte sedimentation rate and C-reactive protein were significantly increased in 10 cases. All patients were negative for autoantibodies. In the course of treatment, 5 cases were treated with glucocorticoids, 7 cases with immunosuppressants, and 7 cases with biological agents. Conclusions: TRAPS is clinically characterized by recurrent fever accompanied by joint, gastrointestinal, skin, and muscle involvement. Inflammatory markers are elevated, and autoantibodies are mostly negative. Treatment mainly involves glucocorticoids, immunosuppressants, and biological agents.

[The correlations between influenza and meteorological factors in 15 cities of northern China, 2008-2020]

Objective: To understand the influence of meteorological factors on the morbidity of influenza in northern cities of China and explore the differences in the influence of meteorological factors on the morbidity of influenza in 15 cities. Methods: The monthly reported morbidity of influenza and monthly meteorological data from 2008 to 2020 were collected in 15 provincial capital cities, including Xi 'an, Lanzhou, Xining, Yinchuan and Urumqi (5 northwestern cities), Beijing, Tianjin, Shijiazhuang, Taiyuan, Hohhot, Ji'nan, Zhengzhou (7 northern cities), Shenyang, Changchun and Harbin (3 northeastern cities). The panel data regression model was applied to conduct quantitative analyze on the influence of meteorological factors on influenza morbidity. Results: The univariate and multivariate panel regression analysis showed that after controlling the population density and other meteorological factors, for each 5 ℃ drop of monthly average temperature, the morbidity change percentage (MCP) of influenza was 11.35%, 34.04% and 25.04% in the 3 northeastern cities, 7 northern cities and 5 northwestern cities, respectively, and the best lag period months was 1, 0 and 1 month; When the monthly average relative humidity decreased by 10%, the MCP was 15.84% in 3 cities in northeastern China and 14.80% in 7 cities in northern China respectively, and the best lag period months was 2 and 1 months respectively; The MCP of 5 cities in northwestern China was 4.50% for each 10 mm reduction of monthly accumulated precipitation, and the best lag period months was 1 month; The MCPs of 3 cities in northeastern China and 5 cities in northwestern China were 4.19% and 5.97% respectively when the accumulated sunshine duration of each month decreased by 10 hours, the best lag period months was 1 month. Conclusions: In northern cities of China from 2008 to 2020, the temperature, relative humidity, precipitation and sunshine duration all had negatively impact on the morbidity of influenza, and temperature and relative humidity were the main sensitive meteorological factors. Temperature had a strong direct impact on the morbidity of influenza in 7 cities in northern China, and relative humidity had a strong lag effect on the morbidity of influenza in 3 cities in northeastern China. The duration of sunshine in 5 cities in northwestern China had a greater impact on the morbidity of influenza compared with 3 cities in northeastern China.

[Assessment of intensity of seasonal influenza activity in Beijing-Tianjin-Hebei region, 2019-2021]

Objective: To explore the feasibility of moving epidemic method (MEM) in the assessment of seasonal influenza (influenza) activity intensity from the perspective of urban agglomeration, assess influenza activity intensity in the Beijing-Tianjin-Hebei region from 2019 to 2021 and evaluate the reliability of surveillance data and the effectiveness of the MEM model application. Methods: The weekly reported incidence rate (IR) of influenza and the percentage of influenza-like illness (ILI%) from 2011-2021 in Beijing-Tianjin-Hebei region were collected to establish MEM models respectively. The model fitting effect and the reliability of the two data were evaluated for the purpose of establishing an optimal model to assess the influenza activity intensity in Beijing-Tianjin-Hebei region from 2019-2021. A cross-validation procedure was used to evaluate the performance of the models by calculating the Youden's index, sensitivity and specificity. Results: The MEM model fitted with weekly ILI% had a higher Youden's index compared with the model fitted with weekly IR at both Beijing-Tianjin-Hebei region level and provincial level. The MEM model based on ILI% showed that the epidemic threshold in Beijing-Tianjin-Hebei region during 2019-2020 was 4.42%, the post-epidemic threshold was 4.66%, with medium, high and very high intensity thresholds as 5.38%, 7.22% and 7.84%, respectively. The influenza season during 2019-2020 had 10 weeks (week 50 of 2019 to week 7 of 2020). The influenza season started in week 50 of 2019, and the intensity fluctuated above and below medium epidemic level for six consecutive weeks. The high intensity was observed in week 4 of 2020, the threshold of very high intensity was excessed in week 5, and the intensity gradually declined and became lower than the threshold at the end of the influenza season in week 8. The epidemic threshold was 4.29% and the post-epidemic threshold was 4.35% during 2020-2021. Influenza activity level never excessed the epidemic threshold throughout the year, and no epidemic period emerged. Conclusions: The MEM model could be applied in the assessment of influenza activity intensity in Beijing-Tianjin-Hebei region, and the use of ILI% to assess influenza activity intensity in this region was more reliable than IR data. Influenza activity intensity in Beijing-Tianjin-Hebei region was higher during 2019-2020 but significantly lower in 2020-2021.

[Reproducibility evaluation of air-charged catheter for rest urethral pressure profilometry]

We retrospectively included 53 (9 males, 44 females) patients who underwent rest urethral pressure profilometry (RUPP) due to lower urinary tract symptoms (LUTS) in Beijing Chaoyang Hospital from May 2021 to March 2022. The age of patients was (55±16) (25-76) years old. The clinical diagnoses of the included patients with lower urinary tract symptoms were classified as: benign prostatic hyperplasia in 9 cases, interstitial cystitis in 1 case, stress urinary incontinence in 11 cases and non-obstructive dysuria in 32 cases. The full set of urodynamic examination was composed of bladder pressure measurement during the filling period, pressure flow study (PFS) and RUPP. All the urodynamic examination was performed by air-charged catheter (ACC) and corresponding equipment. All patients underwent RUPP measurements twice. The vesical pressure (Pves) values were (35.30±6.15), (35.81±5.91) cmH₂O (1 cmH₂O=0.098 kPa); the Pura@max were (141.91±36.53), (145.02±38.85) cmH₂O; functional urethral length were (41.70±16.34), (42.55±16.40) mm; the maximum urethral closure pressure for the two RUPP measurements were (106.57±36.44), (109.41±39.27) cmH₂O. There was no statistical difference between the two RUPP measurements (P>0.05). The reproducibility of the RUPP measurements obtained by ACC is good and deserves further study.

[A monogenic lupus family caused by homozygous deletions of DNASE1L3 gene and literature review]

Objective: To report the clinical features and genetic variations of monogenic lupus caused by DNASE1L3 deficiency and to introduce preliminary experience on diagnosis and treatment for this disease. Methods: Clinical data of 3 children from the same pedigree were collected who were diagnosed with DNASE1L3 defect-associated monogenic lupus in August 2020 by Department of Pediatrics, Peking Union Medical College Hospital referred from Department of Pediatrics, Boai Hospital of Zhongshan. DNA was extracted from the peripheral blood of the patients and their parients to perform genetic analysis and confirmation. Six interferon-stimulated genes were relatively quantified to examine the activation of the type I interferon signaling. "DNASE1L3" "systemic lupus erythematosus" and "SLE" were searched in PubMed, Wangfang Data, CNKI databases for related reports from database established date to June 2022. Spectrum of genetic variations and clinical phenotypes were analyzed in combination with this pedigree. Results: Case 1, a 14-year-old girl with edema, hematuria, and heavy proteinuria, presented with membranous nephropathy. Case 2, the 12-year-old younger brother of case 1 with hematologic, cardiac, pulmonary, renal involvement, positive antinuclear antibody, positive anti-double-stranded DNA antibody and low complement C3, manifested with systemic lupus erythematosus. Case 3, the 8-year-old younger sister of case 1 with hematologic, cardiac, pulmonary and renal involvement, positive antinuclear antibody, positive anti-double-stranded DNA antibody, and low complement C3 and C4, manifested with systemic lupus erythematosus. Genetic testing revealed that all 3 patients carried homozygous deletions in exons 3 and 4 on DNASE1L3 gene. Interferon scores were elevated in case 1, 2 and their parents but normal in case 3. All 3 patients were diagnosed with monogenic lupus caused by DNASE1L3 defects. Literature searching identified 10 relevant publications in English and 0 publication in Chinese, involving 42 patients from 18 pedigrees (including the 3 cases from this pedigree). Nine variants were found: c.289_290delAC (p.T97Ifs*2), c.643delT (p.W215Gfs*2), c.320+4delAGTA, c.321-1G>A, Ex5 del, c.433G>A, c.581G>A (p.C194Y), c.537G>A (p.W179X), and Ex3-4 del. The hotspot variants were c.643delT (43% (36/84)) and c.289_290delAC (36% (30/84)). Kidney was affected in 31 cases (74%) of the 42 cases. Among the 25 patients, joints were affected in 16 cases (64%), fever were reported in 13 cases (52%) hematologic system was involved 13 cases (52%), rash was present in 10 cases (40%), intestinal tract was involved in 8 cases (32%), lungs were involved in 6 cases (24%), eyes were involved in 4 cases (16%), and the heart was involved in 4 cases (16%). The 2 cardiopulmonary affected patients from literature showed poor prognosis, with 1 died, and 1 right heart failure. Conclusions: The clinical manifestations of monogenic lupus caused by DNASE1L3 defect are highly heterogenous, primarily with renal, blood, joint, intestinal, and cardiopulmonary involvement. There is no correlation between the genotype and the phenotype. DNASE1L3 defects were predominantly mediated by null varations including nonsense, splicing, frameshift and exon deletions. The hotspot variants are c.643delT and c.289_290delAC. DNASE1L3 defects should be cautioned in early-onset lupus-like patients with renal, joint and hematologic involvement. Cardiopulmonary involved patients require close monitoring for poor prognosis. Copy number variations should be carefully analyzed after negative whole exome sequencing.

[Clinical analysis of 49 cases of non-inflammasome related conditions]

Objective: To summarize the clinical characteristics and provide clues for early identification of non-inflammasome related conditions. Methods: The clinical manifestations, laboratory tests, genetic testing and follow-up of 49 children with non-inflammasome related conditions in Peking Union Medical College Hospital from January 2006 to February 2022 were retrospectively analyzed. Results: A total of 49 children, 29 of them were boys and 20 were girls. The age of onset was 0.8 (0.3, 1.6) years, the age at diagnosis was 5.7 (2.8, 8.8) years, and the time from onset to diagnosis was 3.6 (1.9, 6.3) years. Combined with genetic testing results, 49 children with non-inflammasome related conditions were found, including 34 cases (69%) of Blau syndrome, 4 cases (8%) of tumour necrosis factor receptor-associated periodic syndrome, 4 cases (8%) of haploinsufficiency of A20, 2 cases (4%) of Majeed syndrome, 2 cases (4%) of pyogenic sterile arthritis, pyoderma gangrenosum, acne syndrome and 3 cases (6%) of chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature syndrome. There were 22 cases (45%) with a positive family history. The clinical manifestations included 37 cases (76%) cases with rash, 38 cases (78%) with joint involvement, 33 cases (67%) with eye involvement, 17 cases (35%) with recurrent fever. In addition, 11 cases (22%) were complicated with digestive system involvement. Thirty cases (61%) presented as elevated inflammatory indexes (erythrocyte sedimentation rate and (or) C-reactive protein), positive autoantibodies were noticed in 3 cases (6%). The patients were treated with glucocorticoid in 23 cases (47%), immunosuppressive agents in 43 cases (88%) and biologic agents in 37 cases (76%). During the follow-up of 5.8 (2.9, 8.9) years, 3 cases (6%) died. Conclusions: The symptoms of non-inflammasome related conditions include recurrent fever, rash, joint and ocular involvement with increased inflammatory indexes and negative autoantibodies. Up to now, glucocorticoids, immunosuppressants and biologic agents are the most popular medications for the non-inflammasome related conditions.

[Analysis on characteristic of pulmonary tuberculosis cases reported in children from four provinces in China, 2019-2021]

Objective: To analyze the reported characteristics of pulmonary tuberculosis (TB) in children aged 0-14 years in four provinces (municipalities), Beijing, Hubei, Chongqing and Sichuan, in China, and provide evidence for the prevention and control of pulmonary TB in children. Methods: The incidence data of childhood pulmonary TB were collected from notifiable disease and tuberculosis management information system of Chinese information system for disease control and prevention,and descriptive epidemiological methods were used to analyze the medical care seeking flow, characteristics and management inclusion of pulmonary TB cases in children. Statistical analysis and data visualization were conducted with softwares Excel 2015, R 4.1.2 and Echart 4.7.0. Results: A total of 6 811 pulmonary TB cases in children were reported in the four provinces during 2019-2021, in which 4 741 (69.6%) were clinically diagnosed and 2 070 (30.4%) were laboratory confirmed. A total of 526 medical institutions reported TB cases in children, including 356 general hospitals (67.7%, 356/526) reporting 4 706 cases, 11 infectious disease hospitals (2.1%, 11/526) reporting 836 cases and 5 children's hospitals (1.0%, 5/526) reporting 542 cases. A total of 6 249 (91.7%) local cases and 562 (8.3%) non-local cases were reported. The reported local incidence rates of TB from 2019-2021 were 6.20/100 000, 7.10/100 000 and 7.20/100 000, respectively, showing an increase trend year by year. The sex ratio of the cases were 0.98∶1(3 373∶3 438). The cases were mainly distributed in age group 10-14 years (4 887 cases, 71.8%). The cases were mainly students (5 167 cases, 75.9%). The management inclusion rates of the local cases and non-local cases were 20.60% and 2.67%, respectively. Conclusions: The main medical institutions reporting pulmonary TB cases in children were children's hospitals, infectious disease hospitals and TB special hospitals, the incidence of pulmonary TB in children in Sichuan was higher. In 2020, the inter-provincial medical seeking behavior of the pulmonary TB cases decreased significantly. The incidence rate in boys was lower than that in girls, and children aged 10-14 years were the population with high incidence of pulmonary TB. The management inclusion rate in non-local cases was lower than that in local cases.

Identification and Verification of the Ability of Cdk5 to Phosphorylate Deubiquitinating Enzyme BRCC3 In Vitro

It is known that the expression of the deubiquitinating enzyme BRCA1-BRCA2-containing complex subunit 3 (BRCC3) and cyclin-dependent protein kinase 5 (Cdk5) is increased in Parkinson's disease (both are involved in neuroinflammatory response). However, the regulatory mechanism of Cdk5 on the post-translational modification of BRCC3 remains unclear. Here we studied whether Cdk5 phosphorylates BRCC3. Phosphorylation of BRCC3 by Cdk5 was predicted by GPS 5.0 software. His-BRCC3 plasmid was constructed by cloning the BRCC3 gene into pGEX-6P-1 vector, and then His-BRCC3 fusion protein was induced with isopropyl β-d-1-thiogalactopyranoside and purified using His-Tag affinity chromatography purification agarose. Phosphorylation of BRCC3 fusion protein by Cdk5 in vitro was detected by mass spectrometry and Western blotting. The results showed that multiple phosphorylation sites were predicted by GPS 5.0, and the His-BRCC3 fusion protein was successfully induced and purified. In vitro kinase assay, Western blotting, and mass spectrometry showed that Cdk5 can phosphorylate BRCC3. It has been demonstrated that protein kinase Cdk5 can phosphorylate the deubiquitinating enzyme BRCC3 in vitro, which provides new data for further study on the mechanism of neurodegeneration.

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

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

[Comparative analysis on seroprevalence of hepatitis B in Guangzhou in 2008 and 2018]

Objective: To compare the seroprevalence of hepatitis B in Guangzhou in 2008 and 2018. Methods: According to the proportion of Guangzhou population size, two-stage cluster sampling was used to select the residents aged 1-59 years in the two surveys. Results: 4 989 and 3 980 people aged 1-59 years were involved in 2008 and 2018, respectively. HBsAg prevalence was 9.50% (95%CI:7.34%-11.66%) in 2018 and 12.45% (95%CI:10.58%-14.33%) in 2008 among the people aged 1-59 years, with no significant difference statistically (χ²=18.302, P=0.075). The decrease of HBsAg prevalence was mainly in the population aged 7-16 years. For the people aged 7-16 years, the HBsAg prevalence was 0.88% (95%CI: 0.35%-1.42%) in 2018 and decreased by 80.62% as compared with the rate 4.54% (95%CI:2.71%-6.36%) in 2008, with statistically significant difference (χ²=34.144,P=0.000). Anti-HBs prevalence was 72.30% (95%CI:69.56%-75.04%) in 2018 and ascended by 11.35% as compared with the rate of 64.93% (95%CI:61.65 %-68.22%) in 2008 among the people aged 1-59 years, with statistically significant difference (χ²=51.618, P=0.001). The rise of anti-HBs prevalence was mainly in the population aged 17-59 years. For the people aged 17-59 years, the anti-HBs prevalence was 71.93% (95%CI: 68.90%-74.96%) and risen by 12.80% as compared with the rate of 63.77% (95%CI: 60.16%-67.37%) in 2008, with a statistically significant difference (χ²=28.422, P=0.001). HBV infection rate was 48.10% (95%CI: 43.20%-53.00%) in 2018 and decreased by 22.76% as compared with the rate of 62.27% (95%CI: 59.11%-65.44%) in 2008, with statistically significant difference (χ²=167.138, P=0.000). The HBV infection rates in the population aged 1-6 years, 7-16 years, and 17-59 years were 4.58%, 5.13%, and 56.56% (a decrease of 81.83%, 85.91%, and 18.47%), respectively. The infection rate of HBV was 48.87% (a decrease of 24.70%) in high epidemic areas and 28.81% (a decrease of 38.75%) in people with a history of hepatitis B immunization. Conclusion: The prevention and control of hepatitis B in Guangzhou have achieved remarkable results it already reached the national goal of reducing HBsAg prevalence to less than 1% among children under five years since 2008. However, the target goal of reducing the hepatitis B mortality rate is quite demanding. The neonatal hepatitis B vaccination and monitoring and screening in adults are still needed.

[A multicentric study on clinical characteristics and antibiotic sensitivity in children with methicillin-resistant Staphylococcus aureus infection]

Objective: To investigate the clinical characteristics of pediatric methicillin-resistant Staphylococcus aureus (MRSA) infection and the antibiotic sensitivity of the isolates. Methods: The clinical data of children with MRSA infection and antibiotic sensitivity of the isolates from 11 children's hospitals in Infectious Diseases Surveillance of Paediatrics (ISPED) group of China between January 1, 2018 and December 31, 2018 were collected retrospectively. The children's general condition, high-risk factors, antimicrobial therapy and prognosis, differences in clinical disease and laboratory test results between different age groups, and differences of antibiotic sensitivity between community-acquired (CA)-MRSA and hospital-acquired (HA)-MRSA were analyzed. The t test and Wilcoxon rank sum test were used for statistical analysis of the quantitative data and Chi-square test were used for comparison of rates. Results: Among the 452 patients, 264 were males and 188 were females, aged from 2 days to 17 years. There were 233 cases (51.5%) in the ≤1 year old group, 79 cases (17.5%) in the>1-3 years old group, 29 cases (6.4%) in the >3-5 years old group, 65 cases (14.4%) in the >5-10 years old group, and 46 cases (10.2%) in the>10 years old group. The main distributions of onset seasons were 55 cases (12.2%) in December, 47 cases (10.4%) in February, 46 cases (10.2%) in November, 45 cases (10.0%) in January, 40 cases (8.8%) in March. There were 335 cases (74.1%) CA-MRSA and 117 (25.9%) cases HA-MRSA. Among all cases, 174 cases (38.5%) had basic diseases or long-term use of hormone and immunosuppressive drugs. During the period of hospitalization, 209 cases (46.2%) received medical interventions. There were 182 patients (40.3%) had used antibiotics (β-lactams, glycopeptides, macrolides, carbapenems, oxazolones, sulfonamides etc) 3 months before admission. The most common clinical disease was pneumonia (203 cases), followed by skin soft-tissue infection (133 cases), sepsis (92 cases), deep tissue abscess (42 cases), osteomyelitis (40 cases), and septic arthritis (26 cases), suppurative meningitis (10 cases). The proportion of pneumonia in the ≤1 year old group was higher than the >1-3 years old group,>3-5 years old group,>5-10 years old group,>10 years old group (57.5% (134/233) vs. 30.4% (24/79), 31.0% (9/29), 38.5% (25/65), 23.9% (11/46), χ(2)=17.374, 7.293, 7.410, 17.373, all P<0.01) The proportion of skin and soft tissue infections caused by CA-MRSA infection was higher than HA-MRSA (33.4% (112/335) vs. 17.9% (21/117), χ(2)=10.010, P=0.002), and the proportion of pneumonia caused by HA-MRSA infection was higher than CA-MRSA (53.0% (62/117) vs. 42.1% (141/335), χ(2)=4.166, P=0.041). The first white blood cell count of the ≤1 year old group was higher than that children > 1 year old ((15±8)×10(9)/L vs. (13±7)×10(9)/L, t=2.697, P=0.007), while the C-reactive protein of the ≤1 year old group was lower than the 1-3 years old group,>5-10 years old group,>10 years old group (8.00 (0.04-194.00) vs.17.00 (0.50-316.00), 15.20 (0.23-312.00), 21.79(0.13-219.00) mg/L, Z=3.207, 2.044, 2.513, all P<0.05), there were no significant differences in procalcitonin (PCT) between different age groups (all P>0.05). After the treatment, 131 cases were cured, 278 cases were improved, 21 cases were not cured, 12 cases died, and 10 cases were abandoned. The 452 MRSA isolates were all sensitive to vancomycin (100.0%), linezolid (100.0%), 100.0% resistant to penicillin, highly resistant to erythromycin (85.0%, 375/441), clindamycin (67.7%, 294/434), less resistant to sulfonamides (5.9%, 23/391), levofloxacin (4.5%, 19/423), gentamicin (3.2%, 14/438), rifampicin (1.8%, 8/440), minocycline (1.1%, 1/91). The antimicrobial resistance rates were not significantly different between the CA-MRSA and HA-MRSA groups (all P>0.05). Conclusions: The infection of MRSA is mainly found in infants under 3 years old. The prevalent seasons are winter and spring, and MRSA is mainly acquired in the community. The main clinical diseases are pneumonia, skin soft-tissue infection and sepsis. No MRSA isolate is resistant to vancomycin, linezolid. MRSA isolates are generally sensitive to sulfonamides, levofloxacin, gentamicin, rifampicin, minocycline, and were highly resistant to erythromycin and clindamycin. To achieve better prognosis. clinicians should initiate anti-infective treatment for children with MRSA infection according to the clinical characteristics of patients and drug sensitivity of the isolates timely and effectively.

Two genetically similar H9N2 influenza viruses isolated from different species show similar virulence in minks but different virulence in mice

The H9N2 influenza virus has been frequently endemic in poultry, infected mammals and humans and has threatened public health. It is therefore imperative to understand the molecular mechanism enabling this virus to jump from avian to mammalian species. In this study, two H9N2 influenza viruses were isolated from the same region in eastern China but from different hosts; one was isolated from mink and named A/Mink/Shandong/WM01/2014(H9N2)(WM01), while the other was isolated from chicken and named A/Chicken/Shandong/LX830/2014(H9N2)(LX830). Sequencing and phylogenetic analysis showed that both H9N2 influenza viruses had similar genetic backgrounds. The results of infection in minks suggested that both viruses caused significant weight loss and pathological changes in the lungs. Mouse infection showed that LX830 was nonpathogenic in mice, but WM01 resulted in 25% mortality and pathological changes in the lungs, such as severe edema and diffused inflammation of the interalveolar septa. Comparison of the full genomes of both H9N2 influenza viruses showed 52-nucleotide-synonym mutations in 8 gene segments and 7-nucleotide-antonym mutations, resulting in 7 amino acid (AA) substitutions distributed in the PB1, PA, NA and M gene segments. None of these mutations did affect splicing of the M and NS gene segments at the nucleotide level or minor open reading frames (ORFs), such as PB1-F2 and PA-X. Phylogenetic analysis showed that both H9N2 influenza viruses belong to the prevalent epidemic genotype in Asia. Keywords: H9N2 influenza virus; chicken; minks; pathogenicity; phylogenetic.

[Comparison of epidemic characteristics between severe acute respiratory syndrome and coronavirus disease 2019]

Objective: To compare epidemic characteristics between severe acute respiratory syndrome (SARS) and coronavirus disease 2019 (COVID-19). Methods: The general information, including epidemiological and clinical data of the confirmed cases during the epidemic period of the two infectious diseases was collected. The data of SARS in Guangzhou was derived from the technical files of Guangzhou Center for Disease Control and Prevention (GZCDC), including the statistical report and brief report of the epidemic situation (from January 2 to May 11, 2003);The data of COVID-19 in Wuhan was derived from the epidemic data published by Wuhan health and Health Committee's official website and other publicly reported documents (from December 9, 2019 to March 11, 2020). Descriptive analysis was used for a comparativeanalysis of the time and age characteristics, the number of cases, basic reproduction number (R0), proportion of medical staff in confirmed cases (%), crude mortality, etc. Results: A total of 1 072 cases of SARS in Guangzhou were included in the study. The incidence ratio of male to female was 1∶1.26. 43 cases of death were reported with a mortality rate of 4.01%. The median age was 36 years old. The proportion of medical staff in the early stage of the epidemic was 29.04% (88 cases). As to COVID-19 in Wuhan, a total of 49 978 cases were included, The incidence ratio of male to female was 1.04∶1. The 2 423 cases of death were reported with a mortality rate of 4.85%. The median age was 56 years old. The proportion of medical staff in the early stage of the epidemic was 30.43% (42 cases). Conclusion: The COVID-19 in Wuhan has the characteristics of high incidence and wide population. However, the epidemic situation is falling rapidly, and the prevention and control strategy needs to be adjusted timely. The prevention and control of nosocomial infection should be addressed in future.

[Analysis on duplicated reporting of brucellosis in China, 2005-2017]

Objective: To analyze the current status of duplicated reporting of brucellosis in China during 2005-2017, to understand the impact of duplicated reporting on the incidence of brucellosis, analyze the possible causes of duplicated reporting, and put forward propose solutions to further improve the brucellosis surveillance data quality. Methods: Data were from brucellosis case reporting cards in National Notifiable Disease Report System (NNDRS), Excel 2010 software was used to establish the database, the duplicated reporting was identified by using Spark DataFrame aggregation analysis in Python 3.2. Results: During 2005-2017, a total of 499 577 cases of brucellosis were reported, but the duplicated reporting rate was 75.76/10 000 (3 785/499 577). The duplicated reporting rate in same year was 37.21/10 000 (1 859/499 577), the duplicated reporting rate in other year was 39.87/10 000 (1 992/499 577) and the overall duplicated reporting rate increased year by year. The duplicated reporting rate in same institution was 33.59% (1 271/3 785) and the duplicated reporting rate by other institutions was 66.41% (2 514/3 785). Hospitals had the highest number of duplicated reporting (2 757), and community healthcare centers had the highest of duplicated reporting rate (281.27/10 000) (123/4 373). The reported incidence of brucellosis was 2.926 4/100 000 in 2017, the corrected incidence was 2.844 8/100 000 after removing the duplicated reporting, which was the maximum decrease from 2005 to 2017, the corrected incidence decreased by 2.79%. From 2005 to 2017, the average reported incidence of brucellosis in Xinjiang Uygur autonomous region was 14.712 0/100 000, and the corrected incidence was 14.060 0/100 000 after removing the duplicate reporting, with a decrease by 4.43%, the biggest decline in China. The average reported incidence of brucellosis in Ningxia Hui autonomous region was 13.987 1/100 000, and the corrected incidence of brucellosis was 13.662 2/100 000, with a decrease of 2.32%, ranking second in China. The reasons for duplicated reporting of brucellosis included repeated medical care seeking in same or different medical institutions in same year or other year, including the repeated medical care seeking in other areas. Conclusions: During 2005-2017, the number of duplicated reporting of brucellosis cases was on the rise in China. Hospital and community health service centers had highest case number and rate of duplicate reporting respectively, the duplicated reporting was mainly caused by re-reporting by other institutions or in other years. The duplicated reporting of brucellosis had greatly affected the accuracy of surveillance data of brucellosis in some provinces, such as Xinjiang and Ningxia. It is recommended to further strengthen brucellosis reporting management, improve data quality of NNDRS.

[AMG-102 inhibits proliferation and induces apoptosis of laryngeal squamous cell carcinoma cells by regulating c-Met/PI3K/Akt pathway]

Objective: To investigate the effects of c-Met inhibitor AMG-102 on the proliferation and apoptosis of laryngeal squamous carcinoma Hep-2 cells and the underlying mechanism. Methods: Laryngeal squamous carcinoma cell line Hep-2 cells were treated with 2.5, 5 and 10 μmol/L AMG-102, respectively. The proliferation activities of Hep-2 cells were detected by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT). The apoptotic rate of Hep-2 cells was detected by flow cytometry analysis and Hoechst staining. The mRNA expression levels of apoptosis-related genes were detected by real-time quantitative polymerase Chain reaction (RT-qPCR), and the protein expressions of c-Met/PI3K/AKT pathway were detected by western blot. Results: Compared with the control group, the proliferation rates of Hep-2 cells treated with 2.5, 5 and 10 μmol/L AMG-102 for 24 hours were (89.8±1.1)%, (79.8±1.0)% and (69.1±1.2)%, respectively; for 48 hours were (76.8±2.0)%, (60.2±1.1)% and (49.8±1.2)%, respectively; for 72 hours were (50.1±2.0)%, (41.5±1.1)% and (33.6±1.0), respectively, with significant differences (all P<0.05). The apoptotic rates of Hep-2 cells treated with 2.5, 5 and 10 μmol/L AMG-102 for 48 hours were (16.09±1.53)%, (27.51±2.02)% and (36.57±1.42)%, respectively, which were significantly higher than (3.62±0.10) % in the control group (all P<0.05). After treated with 2.5, 5 and 10 μmol/L AMG-102 for 48 hours, the relative expression levels of Bcl-2 mRNA in Hep-2 cells were 0.58±0.13, 0.38±0.12 and 0.20±0.13, respectively; the relative protein expression of p-Met were 80.0±3.8, 50.6±4.2 and 28.5±1.3, respectively; the relative protein expression of p-PI3K were 87.1±0.9, 54.2±1.2 and 21.0±1.2, respectively; the relative protein expression of p-AKT were 98.7±5.6, 56.9±3.2 and 32.2±4.3, respectively; which were significantly lower than those in the control group (all P<0.05). The relative expression levels of Bax mRNA were 1.78±0.13, 2.37±0.14 and 3.05±0.13, respectively, and the relative expression levels of caspase-3 mRNA were 1.98±0.14, 2.47±0.14 and 3.15±0.13, respectively, which were significantly higher than those in the control group (all P<0.05). Conclusion: c-Met inhibitor AMG-102 could inhibit the proliferation and induce apoptosis of laryngeal squamous carcinoma Hep-2 cells by regulating the c-Met/PI3K/Akt pathway.

[Clinical study of Chinese Medicine fumigation combined with "Zhuyuan Decoction" in the treatment of chronic rhinosinusitis]

Objective:To investigate the clinical efficacy of "Zhuyuan soup" by combination with fumigation and oral administration on chronic rhinosinusitis（CRS）, further exploring effective Chinese medicine for the disease, and giving full play to the unique advantages of external treatment of traditional Chinese medicine. Method:By using randomized and positive drug controlled methods, patients with moderate-to-severe chronic rhinosinusitis were randomly divided into western medicine group and traditional Chinese medicine group, 30 cases in each group. In the western medicine group, the nasal spray hormone Budesonide was used, and the patients in the traditional Chinese medicine group were treated with the traditional Chinese medicine prescription"Zhuyuan soup"by combination with fumigation and oral administration. All of the above patients were followed up for 2 weeks, and 1 course for 1 month. Visual analogue scores were taken at each follow-up, and CT and nasal endoscopy were performed before and after treatment. Result:The total effective of "Zhuyuan soup" group was 67.1%, which was higher than that of western medicine group（59.6%）, but there was no statistically significant difference（P>0.05）. After treatment, there were no significant differences between the two groups with regard to the symptom of nasal congestion, dizziness, facial pain or fullness, dysosmia, nasal discharge or postnasal drip, total sensation, total symptom score（P>0.05）. According to the total symptom score, the effect of the two groups of patients was not significantly correlated with the gender, age, course of disease, alcohol and tobacco hobbies, previous medication and surgery（P>0.05）. Based on the results of the study, we found that the Chinese medicine group is superior to the western medicine group in improving the total feeling of the disease, dizziness or headache, facial pain or fullness, and postnasal drip, olfactory disorder. Conclusion:Both traditional Chinese medicine and western medicine are effective methods for treating chronic rhinosinusitis. Clinically, individualized comprehensive treatment should be carried out according to the patient's condition. The above methods may be applied alone or in combination with Chinese and Western medicine. Further optimization and improvement of the combination of traditional Chinese and Western medicine in chronic sinusitis can help improve the clinical efficacy and satisfaction of patients, which deserves further study.

[Effect of c-Met inhibitor AMG-102 on radiosensitivity in laryngeal squamous carcinoma cells]

Objective: To investigate the effect of c-Met inhibitor AMG-102 on proliferation and radiosensitivity in laryngeal squamous carcinoma cells. Methods: The effects of AMG-102 on proliferation and radiosensitivity of laryngeal squamous carcinoma cell lines Hep-2 and KBV200 were detected by 3-(4, 5-dimethy-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assay and colony formation assay, respectively. The apoptosis of Hep-2 and KBV200 cells was detected by flow cytometry. The expression levels of c-Met, phospho-Met (p-Met), cleaved caspase-3 and Akt/p-Akt, Erk/p-Erk were detected by Western blot. Specific small interfering RNA targeting c-Met or plasmid of c-Met were transfected into Hep-2 and KBV200 cells to investigate the cell sensitivity to AMG-102. Results: Compared with KBV200 cells, Hep-2 cells were more sensitive to AMG-102 with IC(50) of 14 and 9 μmol/L, respectively. The relative expression levels of c-Met and p-Met proteins in Hep-2 cells were 194.48±0.57 and 177.76±1.53, respectively, which were significantly higher than those in KBV200 cells (171.24±1.00 and 115.37±0.56, respectively, P<0.001 for both). Exogenous hepatocyte growth factor (HGF) was added to increase the expression level of p-Met protein in KBV200 cells. The results showed that AMG-102 significantly reduced the expression of p-Met in KBV200 cells treated with HGF (P<0.001). Compared with the dimethyl sulfoxide (DMSO) group, AMG-102 treatment combined with radiotherapy significantly increased the radiosensitivity of Hep-2 cells (SER=1.28, P<0.001). However, AMG-102 had little effect on the radiosensitivity of KBV200 cells (SER=1.18, P=0.002). Compared with the 4 Gy radiotherapy alone group and the 5 μmol/L of AMG-102 alone treatment group, the apoptosis rate of Hep-2 cells in the combined treatment group was significantly increased. Meanwhile, the expression level of cleaved caspase-3 protein was also markedly increased. However, there were no significant changes in the apoptotic rate and cleaved caspase-3 expression in each treatment group of KBV200 cells. Compared with DMSO treatment group, the expression levels of p-Met, p-Akt and p-Erk were significantly decreased in the 4 Gy radiotherapy group, 5 μmol/L of AMG-102 treatment group and combined treatment group of Hep-2 cells. And the levels of p-Met, p-Akt and p-Erk in the combined treatment group were significantly lower than those in the 4 Gy radiotherapy alone group and 5 μmol/L of AMG-102 treatment alone group. By contrast, in KBV200 cells, the expression of p-Met, p-Akt and p-Erk in each group was not changed. The relative expression of p-Met in Hep-2 cells before and after radiotherapy at 30 min, 1 h, 4 h, 8 h, 24 h were 99.89±0.61, 138.62±1.00, 163.07±5.00, 87.80±1.85, 90.67±0.65 and 94.09±1.41, respectively. The level of p-Met was slightly increased after radiotherapy at 30 min and 1 h (P<0.001 for all), whereas it was significantly decreased from 4 h to 24 h after radiotherapy (P<0.05 for all). By contrast, the expression of p-Met in KBV200 cells did not change with time after radiotherapy (P>0.05). The sensitivity of Hep-2 cells to AMG-102 was decreased after silencing of c-Met, while the sensitivity of KBV200 cells to AMG-102 was not significantly changed (P>0.05). Moreover, the radiosensitivity of Hep-2 cells in c-Met knockdown group had a slightly increasing trend (SER=1.07, P=0.068). After the treatment with 10 μmol/L of AMG-102, the proliferation rate of c-Met ectopically expressed KBV200 cells was 60.05%±3.23%, It was significantly lower than that of the blank control 90.08%±1.04% and siRNA negative control (90.12%±1.01%, P<0.001). The results suggested that the overexpression of c-Met in KBV200 cells increased the radiosensitivity to AMG-102, whereas depletion of c-Met resulted in resistance to AMG-102 in Hep-2 cells. Furthermore, the radiosensitivity of KBV200 cells that overexpressed c-Met showed a decreased trend (SER=0.7, P=0.005). Conclusions: c-Met inhibitor AMG-102 has a significant inhibitory effect on the proliferation of c-Met overexpressing laryngeal squamous carcinoma cells, leading to increased radiosensitivity. It suggests that molecular targeted therapy against c-Met receptor is more effective in c-Met overexpressed subtype of laryngeal squamous cell carcinoma.

[Clinical characteristics of 84 children with invasive Haemophilus influenzae infection from 2014 to 2018]

Objective: To investigate the clinical characteristics of invasive Haemophilus influenzae (HI) infection in children. Methods: The clinical manifestations, laboratory examinations and treatment outcomes of 84 children with HI infection confirmed by bacterial culture in 7 tertiary children's hospitals from 2014 to 2018 were analyzed retrospectively. Results: Among the 84 cases, 50 were males. The age was 1.54 years (ranged from 5 days to 13 years).Twenty cases (24%) had underlying diseases and 48 cases (57%) had not received antibiotics before collecting specimens. Eighty-two cases (98%) had fever and 75 cases (89%) had clear infection foci, among which 31 cases (37%) had meningitis and 27 cases (32%) had pneumonia. Blood culture was positive in 62 cases (74%), cerebrospinal fluid culture was positive in 10 cases (12%), blood culture and cerebrospinal fluid culture were both positive in 11 cases (13%). Antibiotics susceptibility test showed that 27% (22/82) of all HI strains produced β-lactamases and 48% (37/77) strains were resistant to ampicillin. The drug resistance rates to cefuroxime, ampicillin-sulbactam, trimethoprim-sulfamethoxazole and azithromycin were 25% (20/80) , 20% (9/45) , 71% (44/62) and 19%(11/58), respectively. All strains were sensitive to meropenem, levofloxacin and ceftriaxone. After sensitive antibiotic therapy, 83% (70/84) of all patients were cured and improved, the mortality rate and loss of follow-up rate were 13% (11/84) and 4% (3/84) respectively. Conclusions: Meningitis and pneumonia are common presentation of invasive HI infections in children. Mortality in HI meningitis children is high and the third generation of cephalosporins, such as ceftriaxone can be used as the first choice for the treatment of invasive HI infection.

A method for improving the accuracy of non-invasive prenatal screening by cell-free foetal DNA size selection

Background Non-invasive prenatal screening (NIPS) using cell-free foetal DNA (cfDNA) has been widely used for identifying common foetal aneuploidies (e.g. trisomy 21 (T21), trisomy (T18) and trisomy 13 (T13)) in clinical practice. The sensitivity and specificity of NIPS exceeds 99%, but the positive prediction value (PPV) is approximately 70% (combined T21, T18 and T13). Thus, some 30% of pregnant women who have positive NIPS results are eventually identified as normal by amniocentesis. These women therefore must undertake needless invasive tests and risk miscarrying healthy babies because of false positive NIPS results. Methods In order to achieve higher accuracy, we amended the standard NIPS (s-NIPS) protocol with an additional cfDNA size selecting step in agarose-electrophoresis. The advantage of the new method (named e-NIPS) was validated by comparing the results of e-NIPS and s-NIPS using 114 retrospective cases selected from 15,930 cases. Results Our results showed that the foetal cfDNA fraction can be enriched significantly by a size selection step. With this modification, all 98 negative cases and 9 of 11 false positive cases of s-NIPS were correctly identified by e-NIPS, resulting in an increased PPV from 71% to 77%. Additionally, a simulation test showed that e-NIPS is more reliable than s-NIPS, especially when the foetal cfDNA concentration and sequencing coverage are low. Conclusion cfDNA size selection is an important step in improving the accuracy of non-invasive prenatal screening for chromosomal abnormalities.

[Application of recurrent neural network in prognosis of peritoneal dialysis]

OBJECTIVE

Deep learning models, including recurrent neural network (RNN) and gated recurrent unit (GRU), were used to construct the clinical prognostic prediction models for peritoneal dialysis (PD) patients based on routine clinical data. The performance of the RNN and GRU were compared with logistic regression (LR), which is commonly used in medical researches. The possible underlining clinical implications based on the result from the GRU model were also investigated.

METHODS

We used the clinical data from the PD center of Peking University Third Hospital as the data source. Both the baseline data at the beginning of dialysis, and the follow-up and prognostic data of the patients were used by the RNN and GRU prediction models. The hyper-parameters were tuned based on the 10-fold cross-validation. The risk prediction performance of each model was evaluated via area under the receiver operation characteristic curve (AUROC), recall rate and F1-score on the testset.

RESULTS

A total of 656 patients with the 261 occurrences of death were included in the experiment. The total number of all diagnostic records were 13 091. The results on the testset showed that the AUROC of the LR model, RNN model, and GRU model was 0.701 4, 0.786 0, and 0.814 7, respectively. The predictive performances of the GRU and RNN models were significantly better than that of the LR model. The performances of the GRU and RNN models assessed by recall rate and F1-score were also significantly better than that of the LR model, in which the GRU model reached the best performance. In addition, the recall rates were different among different causes of death or by different prediction time windows.

CONCLUSION

The recurrent neural network model, especially the GRU model, is more effective in predicting PD patients' prognosis as compared with the LR model. This new model may be helpful for clinicians to provide timely intervention, thus improving the quality of care of PD.

[Applied study of Singapore occupational semi-quantitative risk assessment technique in occupational health risk assessment in a chair furniture manufacturing enterprise]

Objective: To assess the occupational health risk level of a small-scale furniture manufacturer, and to explore the applicability of the Singapore-developed semi-quantitative occupational risk assessment model for chemical exposure (Singapore model) in small-scale furniture manufacturers, and to provide a basis for the continuous occupational health management of manufacturers. Methods: A small-scale furniture manufacturer was selected as the study subject; an on-site occupational hygiene investigation was performed on the above manufacturer during April to June in 2017, and a risk assessment was carried out using the Singapore model. Results: The assessment results of the Singapore model indicated that risk levels of occupational exposure to harmful chemicals for the key positions in the workplace were inconsistent between the actual exposure level method and the exposure index method except for the following: high risk for formaldehyde exposure (risk level: 3.5 and 4.1, respectively) during woodworking process, high risk for dimethyl benzene exposure (risk level: 3.5 and 3.5, respectively) during burnishing process, medium risk for methyl benzene and dimethyl benzene exposure (risk level: 3.0 and 3.4, respectively) as well as for dimethyl benzene exposure (risk level: 3.0 and 3.3, respectively) during primer coating process, medium risk for methyl benzene exposure (risk level: 3.0 and 3.4, respectively) during gel painting process, and medium risk for cyclohexanone exposure (risk level: 2.8 and 2.8, respectively) during oil polishing process. The exposure index method yielded a higher risk level than the actual exposure level method, especially in the risk level of benzene exposure, which was rated as "high" and "very high" by the former but "low" by the latter. Conclusion: The Singapore model is suitable for risk assessment of occupational exposure to harmful chemicals in small-scale furniture manufacturers, which can provide a basis for further prevention and control measures taken by manufacturers.

[Effect of occupational stress on recurrent spontaneous abortion in women of childbearing age]

Objective: To investigate the influence of occupational stress on recurrent spontaneous abortion (RSA) in women of childbearing age. Methods: From January to December, 2017, 75 working women of childbearing age (25-35 years) who were admitted to a provisional hospital in Lanzhou, China and diagnosed with RSA were assigned into patient group. At a 1∶4 ratio, 300 age-matched working women who had normal first pregnancy were randomly selected as controls. A case-control study was conducted by a self-made questionnaire and the effort-reward imbalance scale. The impact of occupational stress on RSA in women of childbearing age was analyzed by evaluation of occupational harmful factors, regularity, effort-reward ratio, and sleep quality. Results: There were significant differences in the distribution of sleep, daily exercise, night shift, extrinsic-effort/low-reward score, and effort/low-reward score between the patient group and the control group (χ(2)=7.867, P<0.05; χ(2)=7.377, P<0.05; χ(2)=3.714, P<0.05; χ(2)=6.651, P<0.05; χ(2)=8.556, P<0.05) . With controlled factors such as general conditions and living habits, logistic regression analysis showed that poor sleep quality and high-effort/low-reward were risk factors for RSA (odds ratio[OR]=1.462, 95% confidence interval[CI]: 1.032~2.073; OR=3.253, 95%CI: 1.169~9.053) . A regular work was a protective factor against RSA (OR=0.644, 95%CI: 0.438-0.946) . Conclusion: In occupational stress, irregular working hours, lack of sleep, and high-effort/low-reward are risk factors for RSA. Working women of childbearing age should ensure adequate sleep, pay attention to effort-reward balance, and make a regular work schedule.

[Application of surgical cricothyrotomy in emergency and complicated airway management]

Objective:To explore the feasibility of intercricothyrotomy in emergency airway management. Method:Characteristics of 27 cases underwent surgical cricothyrotomy were analyzed. Result:The main causes of emergency were severe trauma of head and neck, larynx stenosis, interspaces infection of the floor of the mouth and submaxillary space, etc; all the patients were divided into 2 groups : surgical cricothyrotomy as the first choice (group A,16/27) and surgical cricothyrotomy after conventional tracheotomy (group B,11/27); The average time of opening airway for group A was much shorter than group B ［(58.12±24.41)s, (739.09±245.29)s,respectively, P<0.01)］; Bleeding in group A (14 cases) was much less than group B (13 cases) ［(2.36±1.16)ml, (4.65±4.31)ml,respectively, P<0.01］; Except 1 cases died from primary disease, 4 cases with laryngeal stenosis underwent laryngeal dilation with T type expansion tube and 2 cases of bilateral recurrent laryngeal nerve palsy, the average time with tracheal tube of the remaining 20 patients was (12.35±7.29)d, no postoperative complications such as larynx or tracheal stenosis were found. All of them were successfully extubation. Conclusion:Surgical cricothyrotomy procedure is fast and safe with simple and convenient that can be used as the preferred method of rapid airway opening when a critical respiratory tract was difficult to manage.

[Experimental observation of hyperbaric oxygen combined with radioactive seed implantation in the treatment of nude mice bearing esophageal squamous cell carcinoma]

Objective: To investigate the effect and mechanism of hyperbaric oxygen combined with radioactive seed implantation in the treatment of esophageal squamous cell carcinoma. Methods: Subcutaneous tumor model of esophageal squamous cell carcinoma using TE-8 cells was established. Tumor bearing Balb/c(nu/nu) mice (60 mice) were divided into four groups, Cont group that treated with normal oxygen level, HBO group that treated with hyperbaric oxygen, RSI group that treated with radioactive seed implantation, and HBO+ RSI group that treated with hyperbaric oxygen combined with radioactive seed implantation. Tumor volume ratio and mean survival time of tumor bearing mice were observed. Pathological changes of tumor tissue after treatment were observed by hematoxylin eosin (HE) staining. Enzyme linked immunosorbent assay kit was used to detect oxidative stress. Apoptosis related proteins were detected by Western blot. Results: After treatment, the tumor volume ratio of HBO+ RSI group was 3.51±0.80 and was significantly lower than that of Cont group, HBO group, and RSI group (P<0.05). The mean survival time of HBO+ RSI group tumor bearing mice was 62 d and was significantly longer than that in Cont group, HBO group, and RSI group (P<0.05). HE staining showed that the pathological changes of tumor tissues were most obvious in HBO+ RSI group. After treatment, the MDA and Bax levels in nude mice of HBO+ RSI group were significantly higher than those in Cont group, HBO group and RSI group, but the levels of GSH, SOD and Bcl-2 were significantly lower than those of Cont group, HBO group and RSI group (P<0.05). Conclusion: Hyperbaric oxygen combined with radioactive seed implantation could slow tumor growth and increase survival time of tumor bearing mice. The possible mechanism is that hyperbaric oxygen combined with radioactive seed implantation can improve the oxidative stress response and the expression of apoptosis protein in tumor bearing nude mice.

Damage to epitaxial GaN layer on Al2O3 by 290-MeV 238U32+ ions irradiation

Micro-structural characteristics and electrical properties of an n-type GaN epilayer on Al₂O₃ irradiated by 290-MeV ²³⁸U³²⁺ ions to various fluences were investigated using atomic force microscopy (AFM), scanning electron microscopy (SEM), high-resolution X-ray diffraction (HRXRD), and Raman scattering spectroscopy. AFM images show that the nano-hillocks generated, and the diameter and density of the nano-hillocks, increase obviously with increasing ion fluence, accompanied by an increase in surface roughness. SEM images display that the Al, O, and C elements appear on the GaN surface, along with a spiral-like, layered volcanic-cone structure formed at the highest-fluence irradiation. HRXRD reveals that the dislocation density increases, as the lattices gradually expand, and that Ga₂O₃ was produced with increasing ion fluence. Raman scattering spectra show that no N and Ga vacancies were produced, the free-carrier concentration decreases, while its mobility first increases and then exhibits a significant reduction with increasing ion fluence.

Fatty acid elongase 5 (ELOVL5) alters the synthesis of long-chain unsaturated fatty acids in goat mammary epithelial cells

Increased production of long-chain unsaturated fatty acids (LCUFA) can have a positive effect on the nutritional value of ruminant milk for human consumption. In nonruminant species, fatty acid elongase 5 (ELOVL5) is a key enzyme for endogenous synthesis of long-chain unsaturated fatty acids. However, whether ELOVL5 protein plays a role (if any) in ruminant mammary tissue remains unclear. In the present study, we assessed the mRNA abundance of ELOVL5 at 3 stages of lactation in goat mammary tissue. Results revealed that ELOVL5 had the lowest expression at peak lactation compared with the nonlactating and late-lactating periods. The ELOVL5 was overexpressed or knocked down to assess its role in goat mammary epithelial cells. Results revealed that ELOVL5 overexpression increased the expression of perilipin2 (PLIN2) and decreased diacylglycerolacyltransferase 2 (DGAT2) and fatty acid desaturase 2 (FADS2) mRNA, but had no effect on the expression of DGAT1, FADS1, and stearoyl-CoA desaturase 1 (SCD1). Overexpression of ELOVL5 decreased the concentration of C16:1n-7, whereas no significant change in C18:1n-7 and C18:1n-9 was observed. Knockdown of ELOVL5 decreased the expression of PLIN2 but had no effect on DGAT1, DGAT2, FADS1, FADS2, and SCD1 mRNA expression. Knockdown of ELOVL5 increased the concentration of C16:1n-7 and decreased that of C18:1n-7. The alterations of expression of genes related to lipid metabolism after overexpression or knockdown of ELOVL5 suggested a negative feedback regulation by the products of ELOVL5 activation. However, the content of triacylglycerol was not altered by knockdown or overexpression of ELOVL5 in goat mammary epithelial cells, which might have been due to the insufficient availability of substrate in vitro. Collectively, these are the first in vitro results highlighting an important role of ELOVL5 in the elongation of 16-carbon to 18-carbon unsaturated fatty acids in ruminant mammary cells.

Videolaryngoscopy vs. Macintosh laryngoscopy for double-lumen tube intubation in thoracic surgery: a systematic review and meta-analysis

Double-lumen intubation is more difficult than single-lumen tracheal intubation. Videolaryngoscopes have many advantages in airway management. However, the advantages of videolaryngoscopy for intubation with a double-lumen tube remain controversial compared with traditional Macintosh laryngoscopy. In this study, we searched MEDLINE, Embase, Cochrane Library and the Web of Science for randomised controlled trials comparing videolaryngoscopy with Macintosh laryngoscopy for double-lumen tube intubation. We found that videolaryngoscopy provided a higher success rate at first attempt for double-lumen tube intubation, with an odds ratio (95%CI) of 2.77 (1.92-4.00) (12 studies, 1215 patients, moderate-quality evidence, p < 0.00001), as well as a lower incidence of oral, mucosal or dental injuries during double-lumen tube intubation, odds ratio (95%CI) 0.36 (0.15-0.85) (11 studies, 1145 patients, low-quality evidence, p = 0.02), and for postoperative sore throat, odds ratio (95%CI) 0.54 (0.36-0.81) (7 studies, 561 patients, moderate-quality evidence, p = 0.003), compared with Macintosh laryngoscopy. There were no significant differences in intubation time, with a standardised mean difference (95%CI) of -0.10 (-0.62 to 0.42) (14 studies, 1310 patients, very low-quality evidence, p = 0.71); and the incidence of postoperative voice change, odds ratio (95%CI) 0.53 (0.21-1.31) (7 studies, 535 patients, low-quality evidence, p = 0.17). Videolaryngoscopy led to a higher incidence of malpositioned double-lumen tube, with an odds ratio (95%CI) of 2.23 (1.10-4.52) (six studies, 487 patients, moderate-quality evidence, p = 0.03).

Parasitism of Spodoptera litura (Lepidoptera: Noctuidae) by Microplitis prodeniae (Hymenoptera: Braconidae)

Spodoptera litura Fabricius is a major vegetable pest that is widely distributed throughout tropical, subtropical and temperate regions. Microplitis prodeniae Rao and Chandry is a solitary endoparasitoid of S. litura. To assess the potential use of this parasitoid as a biological control agent, the reproductive schedule, fecundity and functional response of M. prodeniae were investigated under conditions of 28 ± 1°C and 70 ± 10% relative humidity with a 14:10-h L:D photoperiod. The parasitoid's average lifetime fecundity was 171.0 ± 10.4 eggs, of which approximately 50% were laid within the first 3 days. Additionally, M. prodeniae exhibited a Holling type II functional response, and the estimated maximum numbers of the 1st, 2nd and 3rd instar larvae that were parasitized by a single M. prodeniae female were 71.6, 78.4 and 41.5 larvae over a 24-h period, respectively. The results of this study suggest that M. prodeniae has great potential as a candidate for controlling S. litura and can guide efforts in its mass production.

Peroxisome proliferator-activated receptor delta regulates lipid droplet formation and transport in goat mammary epithelial cells

Even though recent evidence in goat mammary epithelial cells (GMEC) suggest a role of peroxisome proliferator-activated receptor delta (PPARD) in regulating lipid homeostasis, its role is not fully understood. Our hypothesis was that PPARD regulates lipid transport processes in GMEC and, thus, plays a crucial role in regulating fat formation. The PPARD was overexpressed using an adenovirus system (Ad-PPARD) with recombinant green fluorescent protein (Ad-GFP) as the control. Results revealed that overexpression of PPARD markedly upregulated the mRNA abundance of PPARD. Compared with the control (Ad-GFP+dimethyl sulfoxide), overexpression of PPARD alone had no effect on mRNA expression of CD36, SCD1, FABP4, ACSL1, and ADRP. The cultures overexpressing PPARD with the PPARD ligand GW0742 (GW) upregulated the expression of CD36, FABP3, FABP4, ACSL1, and ADRP. Overexpression of PPARD in GMEC plus GW increased the concentration of 16:1 and 18:1-trans and was associated with upregulation of SCD1. Compared with the control (Ad-GFP+dimethyl sulfoxide), the decrease of triacylglycerol concentration coupled with upregulation of genes related to lipid droplet secretion (e.g., ADRP and ACSL1) induced by PPARD overexpression suggests a role in lipid droplet (LD) secretion. Luciferase assay revealed that GW increased the ADRP promoter activity in a dose-dependent manner. Knockdown of PPARD impaired the increase of ADRP promoter activity induced by GW, whereas GW enhanced the activity of ADRP promoter in GMEC overexpressing PPARD. Data with the ADRP 5'-flanking truncated luciferase reporter suggest a core region (-1,444 to -990 bp) response element for the induction of GW. This core region contains a known PPARG response element (PPRE) at -1,003 to -990 bp. When the PPRE was mutated, the overexpression of PPARD had no effect on ADRP promoter activity. Collectively, these results reveal a novel role for PPARD in lipid homeostasis via promoting fatty acid transport and LD formation through a mechanism of direct binding to the promoter of key genes. Hence, PPARD activity may contribute to fatty acid transport and LD formation during lactation.

Effects of cold storage on the biological characteristics of Microplitis prodeniae (Hymenoptera: Braconidae)

The endoparasitoid Microplitis prodeniae Rao and Chandry is an important potential augmentative biological control agent for lepidopteran pests of vegetables and tobacco. However, cold storage of pupae is required to ensure that sufficient parasitoids are available when they are needed in the field. In this study, pupae were maintained at 0, 4 or 10°C for 5-50 days after which the adults were evaluated for emergence, pre-emergence period, sex ratio, female longevity, oviposition period, and fecundity. Cold storage did not affect the pre-emergence period or proportion of females; however, there was a significant reduction in emergence, female longevity, oviposition period, and fecundity with increased exposure to cold. The pre-emergence period was approximately 5 days, and approximately 50% of the emergent parasitoids were females. A cold storage regime of 10 days at 10°C had no effect on the parasitoids and adult emergence was greater than 50% even after 20 days at 10°C. There was no carryover of the cold treatment from parental to F1 and F2 generations. Thus, M. prodeniae can be stockpiled for field release by exposing the pupae to a cold regime and subsequently holding them for adult emergence at 28°C.

[Study on feasibility of enhanced recovery after surgery combined with mobile microendoscopic discectomy-transforaminal lumbar interbody fusion in the treatment of lumbar spondylolisthesis]

Objective: To explore the feasibility of enhanced recovery after surgery (ERAS) combined with mobile microendoscopic discectomy-transforaminal lumbar interbody fusion (MMED-TLIF) in the treatment of lumbar spondylolisthesis and its influence on postoperative rehabilitation. Methods: From October 1 2014 to July 1 2016 , a cohort of 52 patients with lumbar spondylolisthesis who received the program of ERAS-MMED-TLIF were retrospectively reviewed in Department of Minimally Invasive Spine Surgery, Tianjin Hospital.The primary outcomes include the operation time, intraoperative blood loss, length of hospital stay, VAS score (low back pain and leg pain) and Oswestry Disability Index (ODI) at different follow-up time and complication.The height of intervertebral space and fusion rate were also recorded as radiographic indicators. Results: All cases had an average follow-up of 12 months. The mean operative time was (115±30) min with a mean blood loss of (100±35) ml.Compared with preoperative condition, VAS score of low back pain (6.3±3.3 vs 3.5±2.3, P<0.05), VAS score of leg pain (7.1 ± 4.2 vs 3.1 ± 2.6, P<0.05) and the ODI disability index score (43.5±9.6 vs 20.9±7.3, P<0.05) at the postoperative 24 h were decreased and the difference was statistically significant.The mean hospitalized time were (4.9±1.3) days with mean postoperative hospital stay (2.1±1.2) days.Fusion rate was 92.31% (48/52) at the last follow-up time. Conclusion: ERAS combined with MMED-TLIF is feasible in the treatment of lumbar spondylolisthesis, which can significantly reduce intraoperative bleeding, shorten the total length of stay and postoperative hospital stay, improve postoperative pain and promote rapid rehabilitation of patients after operation without increasing the operation time and influencing the long-term effect, it can be applied in clinical practice.

Fatty acid elongase 6 plays a role in the synthesis of long-chain fatty acids in goat mammary epithelial cells

In nonruminants, it is well established that elongation of very long-chain fatty acid-like fatty acid elongase 6 (ELOVL6) catalyzes the synthesis of C18:0 from C16:0 in lipogenic tissues like adipose and liver. However, the role of ELOVL6 in regulating lipid metabolism in ruminant mammary gland remains unknown. In the present study, ELOVL6 was overexpressed or knocked down via adenoviral transfection to assess its role in goat mammary epithelial cells. Results revealed that ELOVL6 overexpression had a weak effect on the expression of genes related to triacylglycerol (TAG) synthesis and desaturation. Overexpression of ELOVL6 increased the content of C18:0 at the expense of C16:0, and increased the elongation index of C16:0. Overexpression of ELOVL6 had no significant effect on the elongation index of C16:1n-7 and the desaturation indices of C16:0 and C18:0. Knockdown of ELOVL6 had a negative effect on mRNA expression of the esterification genes GPAM and diacylglycerolacyltransferase 2 (DGAT2) and TAG concentration; however, it increased the concentration of C16:0 and decreased C18:1n-7 and C18:1n-9 in goat mammary epithelial cells. Accordingly, downregulation of ELOVL6 significantly decreased the elongation indices of C16:0 and C16:1n-7. The lack of change in the desaturation indices of C16:0 and C18:0 upon knockdown of ELOVL6 was consistent with the minor change in SCD1 expression. In conclusion, these are the first results highlighting an important role of ELOVL6 in long-chain fatty elongation and TAG synthesis in ruminant mammary cells.

[Efficacy of intravenous thrombolysis in acute ischemic stroke with hyperdense middle cerebral artery sign]

Objective: To observe the efficacy and safety of recombinant tissue-type plasminogen activator (rtPA) intravenous thrombolysis (IVT) in the treatment of acute cerebral infarction with hyperdense middle cerebral artery sign (HMCAS). Methods: Acute cerebral infarction patients with HMCAS from July 2010 to November 2015 at the First Affiliated Hospital of Dalian Medical University were collected.These patients were divided into two groups depending on whether they received IVT or not.The Nation Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) were used to evaluate early and long-time therapeutic effects.Efficacy and safety were compared between the two groups. Results: A total of 93 patients were eligible for the analysis, with 45 cases in IVT group and 48 cases in non-IVT group.As time went by, NIHSS score in IVT group showed significant downward trend than the non-IVT group.The rate of patients with good outcome in IVT group was higher than that in non-IVT group (P<0.05). The rate of hemorrhage transformation (HT) in IVT group and non-IVT group was 35.6% (16/45) and 10.4% (11/48), respectively, and the difference was statistically significant (P<0.05). While no statistically significant difference was found about the rate of symptomatic intracranial hemorrhage (sICH) (8.9% vs 2.1%, P>0.05) and mortality (33.3% vs 27.1%, P>0.05) between these two groups.Logistic regression analysis identified relativity between IVT treatment and good outcome (P<0.05), hemorrhage transformation (P<0.05), rather than mortality (P>0.05). Conclusions: Intravenous thrombolysis with rt-PA is an effective and safe treatment for most acute ischemic stroke patients with HMCAS and can promote early neurologic improvement and significantly improve long-term functional prognosis.Although Ⅳ thrombolysis can increase the risk of overall HT, it does not add risk in sICH and mortality.

[The influence of vestibular evoked myogenic potential and vestibular caloric test on the prognosis of sudden deafness]

Objective: To explore the effect of vestibular evoked myogenic potential and vestibular caloric test on the prognosis of sudden deafness. Method:One hundred and seven patients with sudden deafness were enrolled in this study, the vestibular evoked myogenic potential(cVEMP ) and vestibular caloric test were evaluated(113 ears). Based upon the results of the tests, patients were divided into cVEMP normal and abnormal groups, vestibular caloric test normal and abnormal groups. The treatment effects were then compared between groups.Result: In seventytwo ears with normal cVEMP, the treatment of 42 ears is effective(58.33%); in fortyone ears with abnormal cVEMP the treatment of 12 ears is effective(29.27%); the difference in the treatment efficiency was significant between the two groups. In sixtyseven ears with normal caloric test, the treatment of 40 ears was effective(59.70%); and in fortysix ears with abnormal caloric test, the treatment of 14 ears is effective(30.43%); the difference in the treatment efficiency between the two groups was significant. Additionally, the treatment of 21 ears with both abnormal cVEMP and caloric test showed ineffective, while the treatment of 28 ears with normal cVEMP and caloric test was effective, which showed significant differences. Conclusion:The prognosis of sudden deafness in patients with normal cVEMP and caloric test is better than the patients with abnormal cVEMP and caloric test, indicating that the results of cVEMP and caloric test can be used to help determine the prognosis of sudden deafness in clinical treatment.

An update on acupuncture point injection

This overview reports the global research advances in acupuncture point injection in the last 5 years. Acupuncture point injection can be applied to a wide range of curable diseases, predominantly those involving pain, but it has poor clinical evidence. Progress has been attained in the mechanism research on acupuncture point injection, but further studies remain necessary. With the reported adverse effects of acupuncture point injection, the need to standardize its clinical procedure has become urgent.

[Effect of intravenous thrombolysis with recombinant tissue type plasminogen activator (rt-PA) in different time windows on acute cerebral infarction patients with atrial fibrillation]

OBJECTIVES

To observe the intravenous thrombolysis effect of rt-PA in different time windows of acute cerebral infarction with atrial fibrillation(AF).

METHODS

Acute cerebral infarction patients who accepted the intravenous thrombolysis treatment with AF from January 2012 to December 2015 were included.According to the time from onset to intravenous thrombolysis, patients were divided into two groups: thrombolysis within 3 h and thrombolysis between 3-4.5 h. The Nation Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) were used to evaluate early and long-time therapeutic effects. The incidence of hemorrhagic infarction(HI), parenchymal hemorrhage(PH) and symptomatic intracranial hemorrhage(sICH) after thrombolysis within 24 hours were observed in the two groups.

RESULTS

A total of 103 patients were included in the study, with 48 cases in thrombolysis within 3 h group and 55 cases in thrombolysis between 3-4.5 h group. After thrombolysis treatment, the 24-hour and 7-day NIHSS score of the two groups were significant lower than before treatment, and the difference was statistically significant(P<0.05). Compared between groups, 24-hour clinical efficacy of thrombolysis within 3 h group was better than that of thrombolysis between 3-4.5 h group, and the difference was statistically significant(P<0.05). There were no statistically significant differences between these two groups about 7-day and 90-day prognosis(P<0.05). The rate of PH in thrombolysis within 3 h group and thrombolysis between 3-4.5 h group is 6.3%(3/48) and 21.8%(12/55) individually, and the difference was statistically significant(P<0.05). While no statistically significant differences was found about the rate of HI(18.8% vs 32.7%, P>0.05) and sICH(8.3% vs 14.5%, P>0.05) between these two groups.

CONCLUSIONS

For patients of acute cerebral infarction with AF, intravenous thrombolytic therapy by rt-PA within 3 h may contribute to a greatly improvement in a short time. Thrombolysis between 3-4.5 h increase the incidence of PH, but do not increase the incidence of sICH. There are no statistically significant differences between these two groups about 90-day favorable prognosis, indicating that thrombolysis between 3-4.5 h is safe and effective for acute cerebral infarction patients with AF.

Molecular identification and genetic variation of varieties of Styphnolobium japonicum (Fabaceae) using SRAP markers

Thirty-four Styphnolobium japonicum varieties were analyzed using sequence-related amplified polymorphism (SRAP) markers, to investigate genetic variation and test the effectiveness of SRAP markers in DNA fingerprint establishment. Twelve primer pairs were selected from 120 primer combinations for their reproducibility and high polymorphism. We found a total of 430 amplified fragments, of which 415 fragments were considered polymorphic with an average of 34.58 polymorphic fragments for each primer combination. The percentage of polymorphic fragments was 96.60%, and four primer pairs showed 100% polymorphism. Moreover, simple matched coefficients ranged between 0.68 and 0.89, with an average of 0.785, indicating that the genetic variation among varieties was relatively low. This could be because of the narrow genetic basis of the selected breeding material. Based on the similarity coefficient value of 0.76, the varieties were divided into four major groups. In addition, abundant and clear SRAP fingerprints were obtained and could be used to establish DNA fingerprints. In the DNA fingerprints, each variety had its unique pattern that could be easily distinguished from others. The results demonstrated that 34 varieties of S. japonicum had a relatively narrow genetic variation. Hence, a broadening of the genetic basis of breeding material is necessary. We conclude that establishment of DNA fingerprint is feasible by means of SRAP markers.

Scaly bionic structures constructed on a polyester fabric with anti-fouling and anti-bacterial properties for highly efficient oil–water separation

Scaly structure bionic structured on the fabric with superhydrophilicity and underwater superoleophobicity. The modified fabric showed excellent separation efficiency for various oil–water mixtures which could solve oil–water separation issue.

Isolation and expression analysis of four HD-ZIP III family genes targeted by microRNA166 in peach

MicroRNA166 (miR166) is known to have highly conserved targets that encode proteins of the class III homeodomain-leucine zipper (HD-ZIP III) family, in a broad range of plant species. To further understand the relationship between HD-ZIP III genes and miR166, four HD-ZIP III family genes (PpHB14, PpHB15, PpHB8, and PpREV) were isolated from peach (Prunus persica) tissue and characterized. Spatio-temporal expression profiles of the genes were analyzed. Genes of the peach HD-ZIP III family were predicted to encode five conserved domains. Deduced amino acid sequences and tertiary structures of the four peach HD-ZIP III genes were highly conserved, with corresponding genes in Arabidopsis thaliana. The expression level of four targets displayed the opposite trend to that of miR166 throughout fruit development, with the exception of PpHB14 from 35 to 55 days after full bloom (DAFB). This finding indicates that miR166 may negatively regulate its four targets throughout fruit development. As for leaf and phloem, the same trend in expression level was observed between four targets and miR166 from 75 to 105 DAFB. However, the opposite trend was observed for the transcript level between four targets and miR166 from 35 to 55 DAFB. miRNA166 may negatively regulate four targets in some but not all developmental stages for a given tissue. The four genes studied were observed to have, exactly or generally, the same change tendency as individual tissue development, a finding that suggests genes of the HD-ZIP III family in peach may have complementary or cooperative functions in various tissues.

The dynamic process and microscopic mechanism of extraordinary terahertz transmission through perforated superconducting films

Superconductor is a compelling plasmonic medium at terahertz frequencies owing to its intrinsic low Ohmic loss and good tuning property. However, the microscopic physics of the interaction between terahertz wave and superconducting plasmonic structures is still unknown. In this paper, we conducted experiments of the enhanced terahertz transmission through a series of superconducting NbN subwavelength hole arrays, and employed microscopic hybrid wave model in theoretical analysis of the role of hybrid waves in the enhanced transmission. The theoretical calculation provided a good match of experimental data. In particular, we obtained the following results. When the width of the holes is far below wavelength, the enhanced transmission is mainly caused by localized resonance around individual holes. On the contrary, when the holes are large, hybrid waves scattered by the array of holes dominate the extraordinary transmission. The surface plasmon polaritions are proved to be launched on the surface of superconducting film and the excitation efficiency increases when the temperature approaches critical temperature and the working frequency goes near energy gap frequency. This work will enrich our knowledge on the microscopic physics of extraordinary optical transmission at terahertz frequencies and contribute to developing terahertz plasmonic devices.

Analysis of the genetic diversity of beach plums by simple sequence repeat markers

The purpose of this study was to measure the genetic diversity of wild beach plum and cultivated species, and to determine the species relationships using SSRs markers. An analysis of genetic diversity from ten beach plum germplasms was carried out using 11 simple sequence repeat (SSR) primers selected from 35 primers to generate distinct PCR products. From this plant material, 44 allele variations were detected, with 3-5 alleles identified from each primer. The analysis showed that the genetic similarity coefficient varied from 0.721 ± 0.155 to 0.848 ± 0.136 within each of the ten beach plum germplasms and changed within the range of 0.551 ± 0.084 to 0.695 ± 0.073 between any two pairs of germplasms. According to the genetic dissimilarity coefficient matrix, a cluster analysis of SSRs using the unweighted pair group mean average method in the NTSYSpc 2.10 software revealed that the ten germplasms could be divided into two groups at the dissimilarity coefficient of 0.606. Class I included 77.8, 12.5, 30, and 33.3% of MM, MI, NY, and CM, respectively. Class II contains the remaining 9 beach plum germplasms. The markers generated by 11 SSR primers proved very effective in distinguishing the beach plum germplasm resources. It was clear that the geographical distribution did not correspond with the genetic relationships among the different beach plum strains. This result will be of value to beach plum breeding programs.

Isolation and characterization of L-valine-degrading Candida maltosa DLPU-zpb for D-valine preparation from DL-valine

To develop a practical process for D-valine preparation from DL-valine, L-valine was used as a sole source of carbon and nitrogen in basal minimal medium to isolate L-valine-degrading micro-organisms. A yeast strain DLPU-zpb was obtained, which showed asymmetric degrading activity against DL-valine. Based on the morphology, physiological and biochemical characteristics, and 26S rDNA D1/D2 domain sequence, strain DLPU-zpb was identified as Candida maltosa. The cells of this strain were used as a biocatalyst for eliminating the L-isomer from DL-valine. The L-isomer was completely degraded within 72 h under the conditions of 30°C, pH control at 6·0, 200 rev min(-1) and 50 g l(-1) DL-valine. The strain DLPU-zpb degraded L-valine effectively but not D-valine, and thus D-valine could be easily isolated from the resultant reaction mixture, which provides a new method for D-valine preparation from DL-valine.

SIGNIFICANCE AND IMPACT OF THE STUDY

D-valine is an important raw material for medicines and its demand is increasing year by year. Several approaches for D-valine preparation have been reported, but none of them are likely to provide product at low cost. A newly isolated L-valine-degrading yeast strain Candida maltosa DLPU-zpb was described, which showed asymmetric degrading activity against DL-valine. Thus, a new and practical process for D-valine preparation from DL-valine could be developed. This is the first report of the asymmetric degrading ability of C. maltosa against DL-valine and D-valine preparation from DL-valine.