[Correlation between pulmonary quantitative CT measurement indicators and respiratory symptoms in patients with chronic obstructive pulmonary disease in stable stage]

Objective: To explore the correlation between pulmonary quantitative CT measurement indicators and respiratory symptoms in patients with stable chronic obstructive pulmonary disease (COPD). Methods: A total of 186 patients with COPD in stable stage who visited in the outpatient department of Beijing Hospital from March 2021 to February 2022 were prospectively included. Demographic data, respiratory symptoms and lung function were collected. The original DICOM data of high-resolution CT (HRCT) were processed using the FACT medical imaging information system and the pulmonary emphysema index pixel index-950 (PI-950) and the airway wall thickness (4-6 T) and the percentage of airway area (4-6 WA%) of the 4-6 generation bronchi which represent the segmental and subsegmental bronchi were measured automatically. According to the modified British medical research council dyspnea scale (mMRC, 0-1 point for low score group, 2-4 points for high score group), chronic obstructive pulmonary disease assessment test (CAT, score<10 points for low score group,≥10 points for high score group), cough, expectoration and wheezing (asymptomatic group and symptomatic group), they were divided into two groups as dependent variables. The relationship between imaging parameters and the above symptoms was evaluated using a logistic regression model. Results: The study ultimately included 186 patients who met the inclusion criteria, including 162 males and 24 females, aged (68.9±9.3) years old. There were 83 patients in the high mMRC group, 120 patients in the high CAT group, 146 patients in the cough group, 154 patients in the expectoration group, and 65 patients in the wheezing group. The age and emphysema parameter PI-950 in the high score group of mMRC were higher than those in the low score group, while the percentage of the forced expiratory volume in 1 second (FEV1) predicted value (FEV1 pred) after medication, the percentage of carbon monoxide diffusion volume (DLCO) predicted value (DLCO pred), and the percentage of the maximum midexpiratory flow (MMEF) predicted value (MMEF pred) after medication were lower than those in the low score group (all P<0.05). The age of the high CAT group was higher than that of the low score group, while FEV1 pred and MMEF pred after medication were lower than those of the low score group (all P<0.05). The proportion of males, patients with smoking history, and smoking index in the cough group were higher than those in the non cough group, while the 4 WA% was lower than that in the non cough group (all P<0.05). The proportion of males, patients with smoking history, smoking index, and PI-950 in the expectoration group were higher than those in the non expectoration group, while FEV1 pred after medication and 4 WA% were lower than those in the non expectoration group (all P<0.05). The 5 WA% and 6 WA% of the wheezing group were higher than those of the non wheezing group, while MMEF pred after medication was lower than that of the non wheezing group (all P<0.05). Multivariate logistic regression analysis showed that after adjusting for demographic characteristics, smoking, combined diseases, lung function and other confounding factors, for every 10% increase in PI-950, the likelihood of developing more severe dyspnea for the patients (high score group according to mMRC) increased by 67.3% (OR=1.673, 95%CI: 1.052-2.658); Every 10% increase in 6WA% increased the likelihood of wheezing by 3.189 times (OR=4.189, 95%CI: 1.070-16.395). No correlation was found between various imaging indicators and cough, expectoration, and CAT scores (P>0.05). Conclusion: Quantitative CT measurement indicators in stable COPD patients can explain the presence and severity of respiratory symptoms, the pulmonary emphysema indicator is associated with dyspnea, and the percentage of proximal airway wall area is associated with wheezing.

[Analysis of factors associated with severe bleeding after percutaneous nephrolithotomy and evaluation of interventional embolization efficacy in male patients]

Objective: To explore the factors associated with severe bleeding after percutaneous nephrolithotomy (PCNL) in male patients and evaluate the efficacy of interventional embolization. Methods: A retrospective case series study was conducted at Nankai Hospital of Tianjin, China, from January 2018 to October 2021. The clinical data of 230 male patients with upper urinary tract stones were analyzed. The observation indicators included age, hypertension, diabetes, renal function abnormalities, history of preoperative anticoagulant use, stone size, stone type, number of puncture channels, operation time and degree of hydronephrosis. To describe the clinical characteristics of bleeding after percutaneous nephrolithotomy in men, and analyze the factors associated with severe bleeding after PCNL. Single factor analysis was performed using the Chi-square (χ2) test, and multivariate analysis was performed using logistic regression analysis. Results: Univariate analysis showed that diabetes mellitus (χ2=4.90, P=0.027), abnormal renal function (χ2=18.32, P<0.001), history of preoperative oral anticoagulants (χ2=5.10, P=0.024), abnormal bleeding and coagulation function (χ2=8.22, P=0.004) and the number of puncture channels (χ2=22.08, P<0.001) were the related factors affecting bleeding after PCNL. Multivariate logistic regression analysis showed that diabetes mellitus (P=0.032), abnormal renal function (P<0.001), and the number of puncture channels (P<0.001) were the independent risk factors of bleeding after PCNL. Of the 28 patients with bleeding after PCNL, 25 were treated with interventional embolization, with a technical success rate of 100.0% and a clinical success rate of 89.3%. Conclusions: For patients with renal calculi and comorbid diabetes, renal function abnormalities, and multiple punctures, relevant preventive measures should be actively administered before PCNL to reduce the risk of postoperative bleeding. For patients with severe bleeding of the kidney after PCNL, TAE is a safe and effective minimally invasive treatment method.

Antiferromagnetic Spin Fluctuations and Unconventional Superconductivity in Topological Superconductor Candidate YPtBi Revealed by ^{195}Pt-NMR

We report ^{195}Pt nuclear magnetic resonance (NMR) measurements on topological superconductor candidate YPtBi, which has broken inversion symmetry and topological nontrivial band structures due to the strong spin-orbit coupling. In the normal state, we find that Knight shift K is field- and temperature independent, suggesting that the contribution from the topological bands is very small at low temperatures. However, the spin-lattice relaxation rate 1/T_{1} divided by temperature (T), 1/T_{1}T, increases with decreasing T, implying the existence of antiferromagnetic spin fluctuations. In the superconducting state, no Hebel-Slichter coherence peak is seen below T_{c} and 1/T_{1} follows T^{3} variation, indicating the unconventional superconductivity. The finite spin susceptibility at zero-temperature limit and the anomalous increase of the NMR linewidth below T_{c} point to a mixed state of spin-singlet and spin-triplet (or spin-septet) pairing.

[Survey on the current situation and influencing factors of humanistic care ability of outpatient and emergency nurses in tertiary Grade A hospitals in Zhengzhou City]

Objective: To investigate the humanistic care consciousness and ability of outpatient and emergency nurses in tertiary Grade A hospitals in Zhengzhou City. Methods: In June 2021, a total of 345 outpatient and emergency nurses from 6 tertiary Grade A hospitals in Zhengzhou City were selected as the survey objects by random number table method. The humanistic care ability of outpatient and emergency nurses was investigated. Multiple linear regression analysis was used to analyze the related factors influencing the humanistic care ability of outpatient and emergency nurses. Results: The total score of humanistic care ability of outpatient and emergency nurses in Zhengzhou tertiary Grade A hospital was (194.18±30.53). The scores of humanistic care ability of outpatient and emergency nurses with different gender, age, educational background, professional title, length of service, night shift frequency, marital status, children's status, employment patterns and average monthly household income were significantly different (P<0.05). Regression analysis showed that education background, length of service, professional title and night shift frequency were independent influencing factors for outpatient and emergency nurses' humanistic care ability (β=0.243, 0.139, 0.163, -0.126, P<0.05) . Conclusion: At present, the humanistic care ability of outpatient and emergency nurses in tertiary Grade A hospitals in Zhengzhou City is still low. Education, length of service, professional title and night shift frequency are independent influencing factors affecting the humanistic care ability of nurses.

[Prevalence, patterns and prognosis of multimorbidity among middle-aged and elderly inpatients with chronic obstructive pulmonary disease]

Objective: To explore the characteristics, patterns of multimorbidity and the impact on quality of life and the prognosis of middle-aged and elderly patients with chronic obstructive pulmonary disease (COPD). Methods: This is a cross-sectional study. From January 2012 to December 2021, 939 middle-aged and elderly COPD patients hospitalized in Beijing Hospital were selected by the convenient sampling method. The basic data of patients and the date of 16 common chronic diseases were collected. Patterns of multimorbidity were depicted by cluster analysis. Generalized linear regression model and logistic regression were used to evaluate the multimorbidity patterns and their prognosis. Results: At least one multimorbidity existed among 93.40% of COPD patients, and the median number of multimorbidity was 3. The top five multimorbidity among the patients were hypertension (57.93%, 544/939), coronary heart disease (33.76%,317/939), heart failure (31.95%,300/939), hyperlipidemia (31.63%,297/939) and arrhythmia (27.37%,257/939). Four multimorbidity patterns were identified, cardiometabolic and metabolic multimorbidity, kidney disease multimorbidity, respiratory-digestive-tumor multimorbidity and other multimorbidity. Cardiometabolic and metabolic multimorbidity was most common (590/939, 62.83%). Compared with non-cardiometabolic and metabolic multimorbidity, the incharge ADL score of patients with this multimorbidity decreased by 7 points (95%CI:-11.22- -3.34), Correspondingly, patients with kidney disease multimorbidity decreased by 14 points (95%CI:-24.12- -3.30) on the incharge score. The presence or absence of kidney disease multimorbidity had the greatest impact on discharge score, which was reduced by 12 points in comparison with patients without this multimorbidity (95%CI:-22.43- -2.40). ICU admission is mostly affected by the presence of cardiometabolic and metabolic multimorbidity (OR=2.44, 95%CI: 1.51-3.92) and kidney disease multimorbidity (OR=2.58, 95%CI: 1.01-6.60). The risk of death is the highest for cardiometabolic and metabolic multimorbidity (OR=2.24, 95%CI: 1.19-4.21). Conclusion: Multimorbidity is common in COPD patients. The most common pattern is cardiometabolic and metabolic multimorbidity. Cardiometabolic and metabolic multimorbidity and kidney disease multimorbidity significantly affect the quality of life and often associate with a poor prognosis.

[Frailty trajectories in people aged 50 years and above in China]

Objective: To identify distinct frailty trajectories in a cohort of nationwide community adults aged 50 years and above, and explore the relationship between frailty trajectories and their socioeconomic characteristics and behavioral factors at baseline survey. Methods: Data were from the three waves of "Global Ageing and Adult Health Research" (SAGE) by World Health Organization in China. The frailty index is generated from 32 items. Group-based trajectory modeling using a censored normal model was conducted to identify the patterns in frailty progression over time. Multinomial logistic regression model was used to examine the effect of socioeconomic status and behavioral factors on the frailty trajectories. Results: A total of 4 303 adults aged 50 years and above with complete data from all three rounds of project were included in the final analysis. Three frailty trajectories were identified: low and stable trajectory (LT) (56.8%), moderately increased trajectory (MT) (34.4%) and highly increased trajectory (HT) (8.8%). The results of the multinomial logistic regression analysis showed that the HT group was more likely to be women (OR=1.88, 95%CI:1.22-2.92) and rural residents (OR=1.87, 95%CI:1.29-2.70) compared with the LT group. In terms of household wealth per capita, there was a clear gradient in ORs, the people with lower household wealth were more likely to be classified in the HT group. Conclusion: This study identified three patterns of progression of frailty trajectories in population aged 50 years and above in China and highlighted that interventions should target those vulnerable populations with rapid progression of frailty.

Spontaneous Ferromagnetism Induced Topological Transition in EuB_{6}

The interplay between various symmetries and electronic bands topology is one of the core issues for topological quantum materials. Spontaneous magnetism, which leads to the breaking of time-reversal symmetry, has been proven to be a powerful approach to trigger various exotic topological phases. In this Letter, utilizing the combination of angle-resolved photoemission spectroscopy, magneto-optical Kerr effect microscopy, and first-principles calculations, we present the direct evidence on the realization of the long-sought spontaneous ferromagnetism induced topological transition in soft ferromagnetic EuB_{6}. Explicitly, we reveal the topological transition is from Z_{2}=1 topological insulator in paramagnetic state to χ=1 magnetic topological semimetal in low temperature ferromagnetic state. Our results demonstrate that the simple band structure near the Fermi level and rich topological phases make EuB_{6} an ideal platform to study the topological phase physics.

[A prospective cohort study on the association between grip strength and cognitive function in adults aged 50 years and above]

Objective: To evaluate the association between grip strength (GS) and cognitive function in a population-based longitudinal cohort of Chinese adults aged ≥50 years. Methods: The study population of 3 600 adults was from the baseline survey and two rounds of follow up of World Health Organization (WHO) study of global ageing and adult health (SAGE) in five districts of Shanghai (Hongkou, Huangpu, Minhang, Qingpu and Pudong) after excluding individuals with self-report stroke and depression. The effects of baseline GS on cognitive function and its changes were evaluated. Factor analysis was applied to generate an overall cognition score based on verbal recall trials, verbal fluency test, forward digit span test and backward digit span test. Linear mixed effects model was used to examine the predictive capability of baseline GS for changes in cognitive function. Results: A total of 3 600 participants aged (61.2±8.1) years at baseline survey were included in this study, including 1 668 (46.3%) men and 1 932 (53.7%) women. The average of baseline GS and total cognitive function score were (28.19±12.18) kg and (58.93±14.56) respectively. Cognitive function score declined significantly during the follow-up, however, the changes were different among different age groups, education level groups and household income groups. After adjusted for age, education level, marital status, household income, co-morbidity of chronic conditions, drinking status, smoking status, physical activity level, vegetable/fruit intakes and BMI, no relationships between the baseline GS and cognitive score at baseline survey and at 1^st follow-up were observed, however, compared with lower GS quartile group, there was a significant relationship between higher baseline GS level and better cognitive function at 2^nd follow-up. The participants with highest GS quartile had better cognitive performance over time (male: β=1.938,95%CI:0.644-3.231,P=0.003, female: β=2.192,95%CI:0.975-3.409,P<0.001 and those aged 50-64 years: β=1.652,95%CI:0.646-2.659,P=0.001) than those with the lowest quartile. Conclusions: Higher baseline GS was significantly related to better cognitive function with slow decline. Thus, it is an indicator of cognitive function in middle-aged and elderly Chinese.

[The influence of meteorological factors on SARS-CoV-2 transmission: evidence from laboratory and epidemiological studies]

SARS-CoV-2 has infected more than 600 million people worldwide and caused more than 6 million deaths. The emerging novel variants have made the epidemic rebound in many places. Meteorological factors can affect the epidemic spread by changing virus activity, transmission dynamic parameters and host susceptibility. This paper systematically analyzed the currently available laboratory and epidemiological studies on the association between the meteorological factors and COVID-19 incidence, in order to provide scientific evidence for future epidemic control and prevention, as well as developing early warning system.

[Cross-sectional study of association between dietary pattern and cognitive performance in people aged 50 and above years in Shanghai]

Objective: To investigate the association between dietary pattern and cognitive performance in local residents aged ≥50 years in Shanghai. Methods: Data were obtained from the second round of Study of Global Ageing and Adult Health (SAGE) survey in Shanghai. Dietary patterns were surveyed by factor analysis. Cognitive tests were conducted to assess subjects' cognitive performance, including verbal recall, verbal fluency and digit test. Multiple linear regression analysis was used to evaluate the relationship between dietary patterns and cognition performance. Results: A total of 4 132 subjects with complete dietary and cognitive performance test data were included. Factor analysis was used to obtain three dietary patterns: including plant-based pattern, high animal-food pattern, high salt-oil pattern. After controlling for gender, age, education level and other factors, it was found that plant-based pattern (β=0.26,95%CI: 0.17-0.36) and high animal-food pattern (β=0.18, 95%CI:0.06-0.29) were positively associated with total cognitive test score while high salt-oil pattern (β=-0.28, 95%CI:-0.85--0.07) was negatively associated with verbal fluency test score. Conclusion: A dietary pattern with high intake of plant food and appropriate intake of animal food might be associated with better cognitive function of residents aged ≥50 years.

[Clinical characteristics and comprehensive treatment of patients with cleidocranial dysplasia]

Objective: To summarize the clinical characteristics of patients with cleidocranial dysplasia (CCD) and analyze their treatment methods. Methods: From January 2000 to December 2020, patients with CCD who completed comprehensive treatment in the Department of Orthodontics and the First Dental Clinic, School and Hospital of Stomatology, China Medical University were retrospectively analyzed. A total of 14 CCD patients [7 males and 7 females, aged (16.1±4.5) years] were collected. There were 153 impacted permanent teeth in this study. In addition to the teeth that needed to be extracted due to special conditions, 147 impacted teeth were pulled into the dentition using closed traction. Patients were divided into adolescent group (≥12 years and<18 years, 10 patients) and adult group (≥18 years, 4 patients). Failure rate of traction was compared between the two groups. Factors affecting the success rate of closed traction such as vertical position of teeth (high, middle and low) and horizontal position of the teeth (palatal, median and buccal) were analyzed. Results: The incidence of maxillary impacted teeth [69.3% (97/140)] was higher than that of mandibular impacted teeth [40% (56/140)]. The difference was statistically significant (χ²=24.22, P<0.001). The supernumerary teeth were mainly located in the premolar area 61.4% (21/44), and most of them were in the palatal region of the permanent teeth 95.5% (42/44). They were generally located at the same height or the occlusal side of the corresponding permanent teeth. The success rate of closed traction was 93.9% (138/147). The success rate in the adolescent group [98.2% (108/110)] was higher than that in the adult group [81.1% (30/37)], and the difference was significant (χ²=14.09, P<0.05). Failure after closed traction of 9 teeth was found totally, including 7 second premolars. The success rate of traction in impacted second premolars at different vertical (χ²=11.44, P<0.05) and horizontal (χ²=9.71, P<0.05) positions in alveolar bone was different significantlly. The success rates of the second premolars were high (15/16), middle (12/13), low (2/7), and lingual palatine (10/17), median (19/19), lip-buccal (0/0), respectively. Conclusions: The closed traction of impacted teeth in patients with CCD was effective, and the age was the main variable affecting the outcome. The success rate of traction in impacted second premolars located in low position vertically or in palatal position was low, which required close observation during treatment.

[Interventional strategies and perioperative complications of chronic total coronary occlusion in combination with bifurcation lesions]

Objective: To analyze the clinical characteristics of chronic total coronary occlusion (CTO) combined with bifurcation lesions and the features of coronary intervention and perioperative complications. Methods: This study adopted retrospective cross-sectional research methods and included 673 patients who underwent interventional therapy for chronic total occlusion in Beijing Anzhen Hospital. According to whether there were side branches (diameter ≥2 mm) within 5 mm before and after the CTO occlusion segment, patients were divided into bifurcation group (337 cases) and non-bifurcation group (336 cases). The measurement data did not conform to the normal distribution and were represented as M (Q₁, Q₃). The clinical risk factors, coronary angiography characteristics, interventional treatment strategies and perioperative complications were compared between the two groups. Results: The patients in the bifurcation group were 60 (51, 65) years old, and 86.6% (292 cases) were male; the patients in the non-bifurcation group were 60 (52, 66) years old, and 83.0% (279 cases) were male.Coronary artery disease in all patients was mainly multivessel disease, of which three-vessel disease accounted for 59.9% (403 cases) and double-vessel disease accounted for 25.4% (171 cases).The target vessel in the bifurcation group was predominantly left anterior descending artery (62.3%, 210 cases), and the target vessel in the non-bifurcation group was more common in the right coronary artery (56%, 188 cases). The target vessel diameter was larger in the bifurcation group (2.91(2.71, 3.24) mm vs 2.80(2.55, 3.13) mm, P<0.001). Most patients used the antegrade technique (88%, 592 cases), and the use of antegrade technique in the bifurcation group (91.9%, 307 cases) was higher than that in the non-bifurcation group (84.8%, 285 cases) (P=0.012). After CTO-PCI, 72.8% (490 cases) of patients achieved successful angiography. A total of 73 patients (10.8%) had perioperative complications, and there was no statistical difference between the two groups. However, the incidence of perioperative myocardial infarction was higher in the bifurcation group (5.9%, 20 cases) than non-bifurcation group (2.7%, 9 cases) (P=0.038). Conclusions: CTO complicated with bifurcation lesions are very common in clinical practice. Most patients with CTO have multiple coronary artery disease at the same time. The target vessel is more common in the left anterior descending artery, and the diameter of the vessel is larger. It is more common to use antergrade technique, accompanied by more perioperative myocardial infarctions.

[Association between lipoprotein (a) level and chronic cardio-renal syndrome in elderly patients]

Objective: To explore the relationship between lipoprotein(a) [Lp(a)] and chronic cardio-renal syndrome (CRS) in elderly patients. Methods: Chronic heart failure (CHF) patients age ≥ 65 years old, who hospitalized in the department of Cardiology of Hebei General Hospital from December 2017 to October 2019, were included in this study. According to the estimate glomerular filtration rate (eGFR) level, patients were divided into CRS group (eGFR<60 ml·min^-1·1.73 m^-2) and CHF group (eGFR ≥60 ml·min^-1·1.73 m^-2). The blood index and basic disease information were collected and compared. Left ventricular ejection fraction (LVEF) were measured by echocardiography. The correlation between clinical indicators and cardio-renal function (LVEF and eGFR) was assessed. The multivariate logistic regression analysis was used to evaluate the related risk factors of CRS in elderly patients; subgroup logistic regression analysis was performed according to the basic disease of patients to assess the relationship between Lp(a) and CRS. Results: A total of 172 elderly patients (85 males (49.4%), aged 79 (71, 84) years) were finally enrolled. Among them, 88 cases (51.2%) were in CRS group and 84 cases (48.8%) were in CHF group. Age (80 (74, 84) years old vs. 74 (70, 82) years old) and LP (a) levels (222.0 (112.0, 445.3) mg/L vs. 155.0 (97.0, 348.7) mg/L) were significantly higher in the CRS group than in the CHF group (P<0.05). Lp(a) levels were negatively correlated with LVEF (r=-0.155, P=0.043) and eGFR (r=-0.220, P=0.004) in total cohort. In the subgroup analysis of patients with 2 high-incidence basic diseases (coronary heart disease and hypertension), Lp(a) was negatively correlated with LVEF (r=-0.250, P=0.007) in the coronary heart disease group, and negatively correlated with eGFR (r=-0.233, P=0.013) in the hypertension group. Multivariate logistic regression analysis showed that age (OR = 1.069, 95%CI: 1.017-1.124, P= 0.009) and Lp(a) (OR = 3.719, 95%CI: 1.339-10.326, P = 0.012) were independent correlates of CRS. The results of logistic regression analysis showed that Lp(a) was an independent correlative factor of CRS in the subgroups of coronary heart disease (OR=3.207, 95%CI: 1.129-9.108, P=0.029) and hypertension (OR=3.054, 95%CI: 1.086-8.587, P=0.034). Conclusion: Serum Lp(a) level is independently related with CRS in elderly patients.

[Association between grip strength, rapid gait speed and cognition in people aged 50 and above in Shanghai during 2009-2010]

Objective: To investigate the association between grip strength, rapid gait speed and cognition in people aged 50 and above in Shanghai. Methods: Cross-sectional data was collected from the World Health Organization (WHO) study on global ageing and adult health (SAGE) wave 1 (2009-2010). A questionnaire survey was conducted among 8 643 participants aged 50 years old and above selected by using multistage random cluster sampling strategies in Shanghai. Factor analysis was applied to evaluate and generate cognitive function overall score.Association between grip strength, rapid gait speed and cognition was examined by a two-level hierarchical linear model. Results: A total of 8 175 participants were included in this study, who were (62.9±9.7) years old, including 3 782 (46.3%) males. The average grip strength and rapid gait speed of participants were (27.46±12.01) kg and (1.44±0.43) m/s respectively. The average scores of verbal recall (VR), verbal fluency (VF), forward digit span (FDS), backward digit span (BDS) and total cognitive scores were (5.72±0.09), (12.67±0.35), (6.84±0.10), (4.32±0.14) and (60.50±0.95) respectively. Grip strength was positively associated with VR, VF, FDS, BDS and overall cognition (standardized β=0.036, 0.079, 0.042, 0.046 and 0.043 respectively, P<0.05), and rapid gait speed was also positively associated with VR, VF and overall cognition (standardized β=0.040, 0.031, 0.039 respectively, P<0.05) after adjusted for age, sex, residence, education level, marital status, household income, co-morbidity of chronic conditions, BMI, drinking, smoking, fruits, vegetables intake and physical activities. Conclusion: Grip strength and rapid gait speed are both positively associated with cognitive function of people aged 50 and above, which would be indicators to evaluate their cognition.

[Association between edentulism and cognition among people aged 50 and over]

Objective: To investigate the association between edentulism and cognition in people aged 50 and over in China. Methods: Cross-sectional data was collected from the first wave of World Health Organization Study on global AGEing and adult health in China, among people aged 50 and over in China. A comprehensive cognitive test was used to assess cognitive functions, including verbal recall (VR), verbal fluency (VF), forward digit span (FDS) and backward digit span (BDS) among the subjects. Association between edentulism and cognition was examined by a two-level (individual level and community level) linear model. Results: A total of 12 843 individuals aged 50 years and over were included for analysis, with an average age of (63.0±9.3) years. The overall prevalence of edentulism was 11.0%. The edentulous adults had lower mean scores of VR (4.55), VF (10.88), FDS (6.25), BDS (2.96) and overall cognition (49.15) (P<0.001). Edentulism was negatively associated with VR (β=-0.216, 95%CI: -0.370 - -0.062), FDS (β=-0.186, 95%CI: -0.293 - -0.078) and overall cognition (β=-1.703, 95%CI: -3.025 - -0.381) after adjusted for age, sex, residence, education level, marital status, household income, co-morbidity of chronic conditions, BMI, smoking and drinking alcohol. Conclusion: Edentulism was related with lower cognition level in people aged 50 and over in China.

[Association between daily sedentary time and frailty among people aged 50 years and over]

Objective: To investigate the association between daily sedentary time and frailty among people aged 50 years and over. Methods: Cross-sectional data was collected from the first wave of World Health Organization Study on global AGEing and adult health in China. A two-level (individual level and community level) logistic model was performed to identify the association between daily sedentary time and frailty. The dose-response relationship between them was analyzed by restrictive cubic spline curve. Results: A total of 13 175 individuals aged 50 years and over were included for analysis. A positive association between daily sedentary time and frailty was noticed, both in urban (OR=1.22, 95%CI: 1.17-1.27) or rural areas (OR=1.11, 95%CI: 1.05-1.18) under study. The dose-response curve showed that daily sedentary time and frailty might present an approximate linear relationship. Conclusion: Results from this study showed significant association exsited between daily sedentary time and frailty, approximately with a linear dose-response relationship.

[Association between frailty and sleep duration among people aged 50 years and over]

Objective: To investigate the association between sleep duration and frailty among people aged 50 years and over. Methods: Cross-sectional data was collected from the first wave of World Health Organization Study on global AGEing and adult health in China. Frailty index was constructed on the proportion of deficits, out of the 40 variables. A two-level (individual level and community level) linear model was performed to identify the related factors on frailty. All the models were stratified by age, gender, residence (urban/rural). Restricted cubic spline was performed to graphically evaluate the dose-response association between self-reported sleep duration and frailty. Results: A total of 13 175 individuals aged 50 years and over participated in this study. Without adjusting on any confounding factors, shorter or longer sleep duration significantly increased the risk of weakness compared with normal sleep time (OR=2.05, 95%CI: 1.71-2.44; OR=1.35, 95%CI: 1.12-1.63). After adjusting for confounding factors such as gender, age, residence, education, family assets, vegetable, smoking, drinking and physical activity, a positive association between short sleep duration and frailty was noticed compared with normal sleep time (aOR=1.60, 95%CI: 1.27-2.01). The results of stratified analysis on sex, age and urban and rural areas showed that, after adjusting for gender, age, residence, education level, family assets, intake of vegetables and fruits, smoking, drinking and physical activity, only shorter sleep duration was positively correlated with the risk of weakness. In addition, among people aged 65 years and over, adjusted for confounding factors, the risk of weakness increased by 91%, compared with normal sleep time (aOR=1.91, 95%CI: 1.46-2.49). The dose-response curve also showed that the sleep duration and frailty present an approximate "U" shaped relationship. Conclusion: Short sleep duration might be associated with frailty.

[Association between low handgrip strength and air pollution among people aged 50 years and over]

Objective: To examine the association between long-term exposure to ambient PM(2.5) combined with indoor air pollution and handgrip strength among people aged 50 and over. Methods: Data were from the first wave of World Health Organization Study on global AGEing and adult health in China. Ambient annual concentration of PM(2.5) was estimated by using the satellite data we also investigated the use of fuels and chimneys as indoor air pollution. A two-level (individual level and community level) linear model was applied to examine the association between long-term exposure to ambient PM(2.5) combined with indoor air pollution and the handgrip strength. Results: A total of 13 175 individuals aged 50 years and over were included for analysis. The handgrip strength was (26.67±0.54) kg. Ambient PM(2.5) was found to be significantly associated with the risk of decreased handgrip strength. Outdoor PM(2.5) concentration was negatively correlated with handgrip strength (β=-0.23, 95%CI: -0.31 - -0.14) decrease in handgrip strength after adjusting for gender, age, residence, education, household assets, intake of vegetables and fruits, smoking and drinking, physical activity. In rural area, compared to those who used solid fuel, use of clean fuel increased (β=1.41, 95%CI: 0.36-2.46) handgrip strength. But in urban area, we did not find any statistically significant association between the use of clean fuel and handgrip strength (β=0.19, 95%CI: -0.95-1.32). Conclusion: This study found that long-term exposure to ambient PM(2.5) combined with indoor air pollution was significantly associated with low handgrip strength among people aged 50 years and over, this suggested that ambient PM(2.5) might serve as one of the risk factors for low physical function seen in the people aged 50 years and over.

[Project profile: Study on global AGEing and adult health in China]

With accelerating and rapid ageing in China, there is an urgent need to collect reliable, valid and cross-nationally comparable data on health in the elderly to provide basis for richer and empirical analysis on the changing health over one's life course and compression of morbidity. To meet the demands of this growing special population, planning and preparing on related social protection mechanisms (health and pension systems) should also based on evidence-based decision-making process. Based on long-term follow-up, large scale cohort study is indispensible for the etiology of common chronic diseases and disabling conditions. This study aims to introduce the background, project objectives, contents, baseline characteristics, strength and weakness as well as prospect, related to the Study on global AGEing and adult health in China.

[Effects of two standards on the overweight trend of infants and toddlers in urban Shanghai]

Objective: To observe and compare the effects of two standards on the overweight trend in urban Shanghai infants and young children. Methods: A cluster randomized controlled trial was conducted in 19 communities in two districts of Shanghai, and the subjects (n=15 019) were divided into S-group and W-group by sealed envelope randomization. The subjects were newborns born between November 2013 and December 2014. The 2005 Shanghai growth standard was applied in the S-group and the 2006 WHO growth standard was used in the W-group. At each follow-up time point age of 1, 2, 4, 6, 9, 12 and 18 months, the outpatient physician assessed the length and weight of the infants according to the standard adopted by each group and provided feeding guidance. The weight-for-age Z scores (WAZ), length-for-age Z scores (LAZ) and weight-for-length Z scores (WLZ) were calculated according to the WHO standard. Weight, length, WAZ, LAZ, WLZ and overweight ratio (WLZ≥2) were compared between the two groups using t test, Wilcoxon test and χ(2) test. Results: A total of 6 509 infants (3 391 were boys, 3 118 were girls) were in the W-group, and 8 510 infants (4 374 were boys, 4 136 were girls) were in the S-group. Among the boys, the weight values at the age of 4, 6, 9, 12, 18 months in the W-group were all lower than those in the S-group ((7.5±0.8) vs. (7.7±0.8) kg, (8.6±0.8) vs. (8.7±0.8) kg, (9.6±0.9) vs. (9.7±0.9) kg, (10.4±1.0) vs. (10.5±1.0) kg, (11.5±1.1) vs.(11.7±1.1) kg; t=4.329, 2.422, 3.739, 2.451, 2.736; P<0.01, 0.015,<0.01, 0.014, 0.009). The length had no significant difference between two groups at all months of age(all P>0.05). The overweight ratio in the W-group was lower than that in the S-group at the age of 9, 12, 18 months(3.3% (71/2 170) vs. 4.9% (143/2 927), 2.5% (51/2 037) vs. 4.5% (126/2 818), 0.8% (7/832) vs. 3.1% (39/1 266); χ(2)=6.520, 14.209, 12.350; P=0.011,<0.01,<0.01).Among the girls, except at the age of 2 months (W-group (5.6±0.6) vs. S-group (5.7±0.6), t=2.935, P=0.003), weight values had no significant difference between the two groups at other age months (all P>0.05).The length in the W-group was higher than that in the S-group at 12 and 18 months of age ((75.6±2.4) vs.(75.5±2.3)cm, (82.4±2.9) vs.(82.2±2.7) cm; t=2.351, 2.197; P=0.019, 0.028). The ratio of overweight in the W-group was lower than that of S-group at the age of 12 and 18 months (1.8% (33/1 871) vs.3.0% (80/2 658), 0.6% (5/790) vs.1.7% (20/1 178); χ(2)=6.764,4.276; P=0.009, 0.039). Conclusions: The application of WHO growth standard can help to reduce the weight gain rate of boys, promote the linear growth of girls, and thus alleviate the overweight trend of infants within 18 months. It suggested that 2006 WHO growth standard should be applied to infants within 1 year of age in Shanghai.

[Operative technique and follow-up effect of endoscopic congenital choanal atresia and dilatation]

Objective:To discuss the operative technique and follow-up effect of endoscopic dilatation and plasty for congenital choanal atresia in infants. Method:Clinical data of 7 children with congenital choanal atresia operative treatmented during September 2016 to January 2018 were analyzed retrospectively. the follow-up were followed closely and analyz the operative effect. Result: Seven cases were diagnosed by electronic nasopharyngoscope, nasal CT confirm the nature of atresia plate, and all 7 case successfully complete the operation. Follow-up survey ranged from 8 months to 23 months, postoperative nasal ventilation is good. The first case of bilateral choanal atresia was removed the nasal stenting after operative 3 months, and founded stenosis 1 month later. Reoperation to enlarge the choanal and retained the nasal stenting for 6 months, no restenosis or atresia after 15 months of follow-up. One patient gave up further treatment because of his own reasons and was lost to follow-up. The other 5 cases had no obvious constriction, good ventilation and no operative complications.Conclusion:Electronic nasopharyngoscope is noninvasive, convenient and accurate in the diagnosis of choanal atresia. Nasal CT confirm the nature of the atresia plate. Endoscopic dilatation and plasty of choanal atresia should be retained the nasal stenting for more than 6 months, avoid re-constriction. .

[Advances in research of odontoid fractures in the elderly]

Odontoid fractures constitute the most common cervical spine fracture in the population aged. The optimal management strategy for odontoid fractures remains controversial, especially in the elderly, because of the high morbidity and mortality with both conservative and operative intervention. This review discusses the management of odontoid fractures among the elderly, with a focus on the various treatment options and their outcomes.

[Subjective well-being feelings and related factors in people aged 50 years or older in Shanghai: Based on Day Reconstruction Method]

Objective: To evaluate the subjective well-being feelings of people aged ≥50 years in Shanghai by using the Day Reconstruction Method (DRM) and explore the related factors. Methods: A cross-sectional survey was conducted from October 2009 to June 2010 among people aged ≥50 years selected through multistage random cluster sampling in Shanghai. DRM was used to assess participants' subjective well-being by net effect and U-index. Univariate and multivariate linear regression models were used to explore the related factors. Results: A total of 8 075 participants were included, with average age of 63.1 years. The mean net effect value was 1.24 (95%CI:1.15-1.33), and the mean U-index was 1.55% (95%CI:1.10%-1.99%). After adjusted for demographic factors, univariate liner regression model indicated that age, education level, marital status, family wealth, residence, self-rated health status, WHODAS score and prevalence of chronic disease were associated with subjective well-being, and multivariate liner regression model indicated that higher WHODAS score was associated with lower net effect value (P<0.05). Conclusion: The subjective well-being feelings of people aged ≥50 years in Shanghai might be associated with age, education level, marital status, family wealth, residence, self-rated health status and WHODAS score. Enhanced social support and appropriate social security system might facilitate the improvement of the subjective well-being of the elderly.

[Simulation of inferior turbinate reduction using computational fluid dynamics methods]

Objective:Two computational fluid dynamic (CFD) models of unilateral inferior turbinate reductions (ITR) were constructed and investigate the influences of aerodynamic consequences.Method:A unilateral hypertrophic inferior turbinate CFD model wasestablished. Two kinds of methods in removing of tissue bulk along the length of the hypertrophic inferior turbinate were used,and we got the model B and the model C. Nasal airflow distribution were computed before and after simulated unilateral inferior turbinate reduction in use of Fluent 6.3.26.Result:Simulated two kinds of ITR resulted in enlargement in the cross-section area of inferior nasal meatus, 0.36 cm² of the model B and 0.89 cm² of the model C in average. Model C produced a less reduction in intranasal pressures (approximately 3 Pa) than the model B and the original model which are the same as approximately 8 Pa. More air was predicted to flow in the affected nasal passage in the model C (approximately 80 ml/s) than the model B and the original model. Airspeed in the anterior valve region was improved significantly and more vortices happened in the model C.Conclusion:The model C is significantly better than the model B in restoring normal anatomy and ventilation physiological of the nasal cavity. So, in ITR recoverying normal anatomy structure of the nasal has decisive significance.

[Incidence of fall related injury in people aged 50 and above and risk factors in 8 provinces in China: a cross-sectional study]

Objective: To estimate the incidence and distribution characteristics of fall related injury in people aged ≥50 years in 8 provinces in China and related physiological, psychological and social risk factors. Methods: Cross-sectional data were collected from adults aged ≥50 years participating in the World Health Organization (WHO) study on global ageing and adult health (SAGE) round 1 in China. Two-level hierarchical logistic model was used to identify the related factors for fall-related injury. All the models were stratified by living area (urban/rural). Results: Estimated incidence of fall related injury (road traffic injury was not included) was 3.2%. Ageing and multiple chronic conditions (OR=2.55, 95%CI: 1.41-4.64) was significantly associated with the incidence of fall related injury in urban area. In rural area, depression (OR=4.33, 95% CI: 2.52-7.42) and multiple chronic conditions (OR=2.46, 95%CI: 1.37-4.41) were associated with the incidence of fall related injury. Conclusions: This study estimated the incidence of fall related injury in adults aged ≥50 years in 8 provinces in China. A significant association between multiple chronic conditions and fall related injury were found in both urban and rural residents. Targeted measures should be taken for the prevention and control of chronic diseases in elderly population.

[Associations of obesity and physical activity with cognition in people aged 50 and above in Shanghai]

Objective: To investigate the associations of obesity and physical activity with cognition in the elderly. Methods: A cross-sectional survey was conducted from October 2009 to June 2010 among people aged ≥50 years selected through multistage random cluster sampling in Shanghai. The subjects' body weight, body height, waist circumference and hip circumference were measured to calculate body mass index (BMI) and waist-hip ratio (WHR), and the data on self-reported physical activity level were collected through questionnaire survey. A comprehensive battery of cognitive tests was conducted to assess subjects' cognitive functions, including verbal recall, forward digit span (FDS), backward digit span (BDS), and verbal fluency (VF). General linear model was used to examine the associations of BMI, WHR and physical activity with cognition. Results: A total of 7 913 participants were included, with a median age of 60 years. Age, sex, education level, income level, BMI, WHR and physical activity level were significantly associated with cognitive scores in univariate analysis. After adjusted for age, sex, education level and income level, BMI was no longer significantly associated with cognitive scores in all cognitive functions (all P>0.01). WHR was significantly associated with VF score (P<0.01). Abdominally obese participants had lower VF score than non-abdominally obese participants (P<0.01). Physical activity level was significantly associated with all cognitive functions (P<0.01). Compared with participants with moderate physical activity level, participants with low physical activity level had lower scores in all cognitive functions (P<0.01). Conclusion: Abdominal obesity and low physical activity level were negatively associated with cognition level in the elderly, suggesting that waist circumference control and physical activity might help maintain cognition in the elderly.

[Correlation between percentage of body fat and simple anthropometric parameters in children aged 6-9 years in Guangzhou]

Objective: To evaluate the accuracy of simple anthropometric parameters in diagnosing obesity in children in Guangzhou. Methods: A cross-sectional study, including 465 children aged 6-9 years, was carried out in Guangzhou. Their body height and weight, waist circumference (WC) and hip circumference were measured according to standard procedure. Body mass index (BMI), waist to hip ratio (WHR) and waist-to-height ratio (WHtR) were calculated. Body fat percentage (BF%) was determined by dual-energy X-ray absorptiometry. Multiple regression analysis was applied to evaluate the correlations between age-adjusted physical indicators and BF%, after the adjustment for age. Obesity was defined by BF%. Receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic accuracy of the indicators for childhood obesity. Area under-ROC curves (AUCs) were calculated and the best cut-off point that maximizing 'sensitivity + specificity-1' was determined. Results: BMI showed the strongest association with BF% through multiple regression analysis. For 'per-standard deviation increase' of BMI, BF% increased by 5.3% (t=23.1, P<0.01) in boys and 4.6% (t=17.5, P<0.01) in girls, respectively. The ROC curve analysis indicated that BMI exhibited the largest AUC in both boys (AUC=0.908) and girls (AUC=0.895). The sensitivity was 80.8% in boys and 81.8% in girls, and the specificity was 88.2% in boys and 87.1% in girls. Both the AUCs for WHtR and WC were less than 0.8 in boys and girls. WHR had the smallest AUCs (<0.8) in both boys and girls. Conclusion: BMI appeared to be a good predicator for BF% in children aged 6-9 years in Guangzhou.

[Value of diffusion-weighted imaging in differentiating sellar malignant germ cell tumors from raniopharyngioma]

Objective: To investigate the diagnostic value of diffusion-weighted imaging (DWI) and apparent diffusion coefficient(ADC) values in the differentiation of sellar malignant germ cell tumors and raniopharyngioma. Methods: This retrospective study included 36 patients(14 cases of malignant germ cell tumor and 22 patients with raniopharyngioma) with histopathologically-confirmed sellar tumors from January 2013 to April 2017 in the First Affiliated Hospital of Zhengzhou University.All patients underwent conventional MRI and DWI before the treatment. ADC maps were reconstructed, and ADC values of the sellar lesions were calculated and compared between the groups. Diagnostic value of ADC was evaluated by receiver operating characteristic(ROC) curves. Results: The mean ADC values of malignant germ cell tumors were significantly lower than that in raniopharyngioma[(0.93±0.23)×10(-3) mm(2)/s vs (1.69±0.21)×10(-3) mm(2)/s, t=-10.19, P<0.01]. The area under the ROC curves of ADC values diagnosing malignant germ cell tumors and raniopharyngioma was 0.987. The optimal cutoff values of ADC for differential diagnosis of malignant germ cell tumors and raniopharyngioma was 1.52×10(-3) mm(2)/s, the sensitivity, specificity and accuracy was 81.2%, 100%, 88.9%, respectively. ADC value had a high consistency with pathological results (Kappa value was 0.887). Conclusion: Malignant germ cell tumors and raniopharyngioma have different ADC value, which can improve the diagnostic accuracy.

[Analysis of 12 cases of exogenous lipoid pneumonia confirmed by pathology]

Objective: To study the etiological, clinical, radiological, diagnostic, therapeutic, and prognostic manifestations of exogenous lipoid pneumonia (ELP), and therefore to improve the diagnosis and treatment of this disease. Methods: The clinical data of 12 cases of ELP confirmed by pathology were retrospectively analyzed. Results: The patients consisted of 9 males and 3 females, with an average age of 73.8 years (range, 44 to 100 years). The underlying diseases were variable, including diseases affecting the general condition (multiple organ failure, chronic heart and renal insufficiency, pemphigoid, etc) and conditions with increased risk of aspiration (sequelae of cerebrovascular disease, Alzheimer's disease, advanced stage of nasopharyngeal carcinoma, paralytic ileus, etc). The 12 cases were all caused by Inhalation of mineral oil. Common symptoms included cough, sputum production and dyspnea. ELP had no special physical signs. Inflammation indexes, such as white blood cell, neutrophil percentage, ESR, C reactive protein, procalcitonin, D-Dimer, and blood lipid levels were usually normal. Radiological features of ELP mainly included consolidation, mass or nodules, with a little ground-glass opacity. Some patients had ventilation and/or diffusion dysfunction. The diagnostic methods included CT-guided percutaneous lung biopsy, thoracoscopy, thoracotomy or autopsy. Histopathological findings showed accumulation of large foamy macrophages in the alveolar spaces, with a few lipid deposition and polykaryocytes. The main treatment of ELP was cessation of lipid material contact. One case died of ELP, 6 died of other coexisting diseases, and the rest 6 improved with treatment and were discharged. The survival patients were all stable during a follow-up of 2-4.5 years. Conclusions: ELP was rare and its clinical manifestation was atypical. Its radiological manifestations were indistinguishable from pneumonia, lung cancer, interstitial lung diseases, etc. Pathological examination was the gold standard for diagnosis, and the preferred means of sampling was bronchoscopy. In cases whose diagnosis could not be confirmed by BALF, CT-guided percutaneous lung biopsy might be considered. The most important treatment is cessation of lipid material contact. The prognosis is good.

[Clinical diagnosis and management of cervical spondylotic amyotrophy]

Objective: To investigate the clinical characteristics and surgical treatment of cervical spondylotic amyotrophy. Methods: Thirteen patients(13 man) with proximal (10) and distal(3) cervical spondylotic amyotrophy between November 2014 and September 2016 were included in this study. The average age of the patients was 55 (range, 47-66) years. The sex, age, clinical course, type of amyotrophy, lesion segment and postdecompression improvement in muscle power were reviewed. Results: Of 13 cervical spondylotic amyotrophy patients, 9 were performed on with cervical disectomy, 2 were performed on with cervical posterior operation, 2 remainding patients received nonoperative treatment. Cervical spondylotic amyotrophy patients were followed up 6-22 (average 10.6) months, muscle power of 4 patients (all proximal-type)were improved completely (the average recovery time were 4.4 months), muscle power of 6 patients were improved uncompletely, 1 patients failed to improve, the 2 remainding patients received nonoperative treatment had no change. Conclusion: Cervical spondylotic amyotrophy as a rare type of cervical spondylotic disorder, It should distinguish cervical spondylotic amyotrophy from amyotrophic lateral sclerosis, especially in the early stage of amyotrophic lateral sclerosis. A surgical treatment is recommended as the first line of proximal-type CSA, especially those with serious compression. It is important that clinicians should be aware that distal-type CSA had a poor results, resulting in a lower lower satisfaction, especially those with no, or insignificant, sensory disturbance.

Gene expression and enzyme activity of lipoprotein lipase correlate with intramuscular fat content in Guangxi san-huang and Arbor Acres chickens

Lipoprotein lipase (LPL) is a key enzyme in lipid metabolism. This study investigated LPL gene expression, LPL enzyme activity, and the correlation of each with intramuscular fat (IMF) in Chinese Guangxi san-huang (GXSH) and Arbor Acres (AA) chickens. The results showed that age and breed had significant effects on LPL expression and enzyme activity. Correlation analyses showed significant positive correlations between LPL expression levels and IMF contents in the breast and thigh tissues of both GXSH (r = 0.712, P = 0.001; r = 0.792, P < 0.001, respectively) and AA (r = 0.644, P < 0.001; r = 0.545, P < 0.001, respectively) chickens. The results also indicated a significant positive correlation between LPL enzyme activity and IMF contents in the breast and thigh tissues of both GXSH (r = 0.615, P = 0.001; r = 0.685, P < 0.001, respectively) and AA (r = 0.600, P = 0.001; r = 0.528, P = 0.003, respectively) chickens. The results indicated that the LPL gene was significantly correlated with IMF in these two breeds. The results presented here could contribute to knowledge of LPL mRNA developmental expression patterns and enzyme activity, and it could facilitate further research on the molecular mechanisms underlying IMF deposition in chickens.

Evolution of the Fermi surface of Weyl semimetals in the transition metal pnictide family

Topological Weyl semimetals (TWSs) represent a novel state of topological quantum matter which not only possesses Weyl fermions (massless chiral particles that can be viewed as magnetic monopoles in momentum space) in the bulk and unique Fermi arcs generated by topological surface states, but also exhibits appealing physical properties such as extremely large magnetoresistance and ultra-high carrier mobility. Here, by performing angle-resolved photoemission spectroscopy (ARPES) on NbP and TaP, we directly observed their band structures with characteristic Fermi arcs of TWSs. Furthermore, by systematically investigating NbP, TaP and TaAs from the same transition metal monopnictide family, we discovered their Fermiology evolution with spin-orbit coupling (SOC) strength. Our experimental findings not only reveal the mechanism to realize and fine-tune the electronic structures of TWSs, but also provide a rich material base for exploring many exotic physical phenomena (for example, chiral magnetic effects, negative magnetoresistance, and the quantum anomalous Hall effect) and novel future applications.

Novel folate-targeted docetaxel-loaded nanoparticles for tumour targeting: in vitro and in vivo evaluation

Cholesterol-PEG₁₀₀₀-FA (folic acid) was synthesized as a stabilizer to encapsulate DTX, for the construction of a promising targeted delivery system for breast cancer therapy.

Novel folate-targeted paclitaxel nanoparticles for tumor targeting: preparation, characterization, and efficacy

To improve tumor targeting of anticancer drugs has recently been the focus of a great deal of research.

Complete mitochondrial genome of the Cyclemys dentata and phylogenetic analysis of the major family Geoemydidae

In the present study, the complete mitochondrial (mt) genome of Cyclemys dentata was determined using PCR reactions. The structural organization and gene order of C. dentata were equivalent to those of most other vertebrates. The mt genome was 16,489 bp in length, has rich A+T content, consisting of 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a control region (D-loop). All protein-coding genes started with ATG, many genes have complete stop codons, except ND2, COX3, ND3, and cyt-b genes had incomplete stop codons of T. The light-strand replication origin (OL) of C. dentata might fold into a stable stem-loop secondary structure, and its loop had 2 nt less than that of the Cyclemys atripons OL sequence. The D-Loop of C. dentata contained a central domain (CD), 2 extended termination associated sequences (ETAS1, ETAS2) and 3 conserved sequence blocks (CSB1, CSB2, CSB3). The average length of 20 turtles' mt genomes was 16,692.5 bp, including 34.1% A, 27.0% T, 26.0% C and 12.9% G. The C. dentata mitochondrial genome could provide useful data for further studies on phylogenetics and conservation genetics of this species. The phylogenetic relationships of the family Geoemydidae were analyzed by maximum-likelihood (ML) and neighbor-joining (NJ) based on concatenated sequences of 13 protein-coding genes from 20 turtle species. The ML and NJ trees had homologous topologies. The results support the existing classification of the genera of Geoemydidae, that C. dentata was a sister species of C. atripons, Pyxidea nested in Cuora, and Chinemys was synonymous with Mauremys.