The system for directional and stable differentiation of amniotic fluid stem cells into neuron-like cells / 中国组织工程研究

BACKGROUND: Neuronal regeneration using stem cell differentiation has gained a lot of attentions from researchers. Although embryonic stem cells and induced pluripotent stem cells have good potential for neuronal differentiation, a high risk of tumor development in vivo limits the further study. OBJECTIVE: To establish a stable system for sorting, culture and neuronal differentiation of amniotic fluid stem cells, and to explore the feasibility as seed cells for neuronal regeneration. METHODS: Amniotic fluid sample (10 mL) was obtained at 19-22 weeks of pregnancy under B-ultrasound guidance, and amniotic fluid stem cells were isolated by c-Kit magnetic beads. The markers Oct-4 and Sox2 of amniotic fluid stem cells were identified by immunofluorescence. The expression levels of c-Kit, Oct-4, Sox2 and Nestin in amniotic fluid stem cells after multiple passages were detected by RT-PCR. Then, the cells were cultured by hanging drop for 4 days to observe the embryoid bodies-like structures. Amniotic fluid stem cells were induced to differentiate into neurons using two-stage method. The expression levels of Neuro D and Tuj1 were observed by immunofluorescence. RESULTS AND CONCLUSION: (1) About 1% of amniotic fluid stem cells were positive for c-Kit. (2) (75.0±4.6)% of amniotic fluid stem cells expressed Oct-4 and (86.0±2.8)% of the cells expressed Sox2. (3) The expression levels of c-Kit, Oct-4, Sox2 and Nestin detected by RT-PCR did not change with passage times. (4) Embryoid bodies-like structures formed after hanging drop culture. (5) Immunofluorescence results showed that amniotic fluid stem cells expressed neuronal marker Tuj1, but without the typical morphological features. RT-PCR detected the expression of Tuj1 in different amniotic fluid stem cell specimens as well as in the same sample after several passages. (6) Amniotic fluid stem cells could have the characteristics of neuron-like cells after induction with basic fibroblast growth factor, brain-derived neurotrophic factor, and neurotrophin factor 3 in two stages, and could express neural stem cell marker Neuro D and neuronal marker Tuj1.

Preparation of thermoresponsive micelles loaded with indocyanine green and doxorubicin for combined therapy in MCF-7 cells / 药学学报

In this study, the thermoresponsive micelles were synthesized with random copolymerization method and the photosensitizer indocyanine green (ICG) was loaded on micelles through the physical adsorption. The light energy was converted into heat energy to increase the temperature after irradiation with near-infrared light. When the phase transition temperature was reached, the micelle was disassembled and the targeted therapy was achieved. The nanoparticles were characterized with a transmission electron microscopy, Fourier transform infrared spectrometer, nuclear magnetic resonance spectrometer and other characterization were used to investigate. The critical micelle concentration (CMC), upper critical solution temperature, the photothermal properties of the carrier and the release of drug triggered by light were investigated after the doxorubicin (DOX) loaded. The carrier was evaluated for toxicity, cellular uptake, the effect of photothermal, the combination of photothermal and chemotherapy; the p(AAm-co-AN)-g-PEG (PAAP) was spherical in shape with a particle size of about 45 nm and a phase transition temperature was about 43℃. The critical micelle concentration was 24 μg·mL-1. The particle size increased to 88 nm after loaded with ICG and DOX which the photothermal effect was obvious. The cumulative release of the drug under the irradiation of near-infrared light (808 nm, 2 W·cm-2, 2 min·h-1) was increased to 59.4% (pH 5.0) after 5 h. The results of the cell experiment indicated that ICG-PAAP was almost non-toxic and uptaken by the lysosomal pathway. The cell killing effect was stronger with combination of chemotherapy (DOX as 20 μg·mL-1) with more than 70% of the cells killed. The results showed that the prepared micelle with low toxicity was thermoresponsive and could be used in combined therapy of tumor under the irradiation of near-infrared light.

Targeted monitoring on healthcare-associated infection in neonates / 中国感染控制杂志

Objective To investigate the occurrence of healthcare-associated infection(HAI)in different weight groups of neonates in neonatal intensive care unit (NICU)and general neonatal wards,and find out the high risk factors for HAI.Methods Targeted monitoring on hospitalized neonates in the neonatal department of a hospital in 2016 and January-November 2017 was prospectively surveyed,HAI rate,device usage rate and device-associated in-fection rate in different weight groups of neonates in NICU and general neonatal wards were compared.Results From 2016 to November 2017,a total of 3 872 neonates were monitored,the total hospitalization days were 42 427 days,56 patients had 62 cases of infection,HAI rate and HAI case rate were 1.45% and 1.60% respectively.HAI rate and HAI case rate in NICU were 5.28% and 6.03% respectively;HAI rate and HAI case rate in general neo-natal wards were both 0.46%,constituent ratio of septicemia ranked first of infection in both NICU and general neonatal wards,accounting for 43.75% and 50.00% respectively,followed by lower respiratory tract(LRT)infec-tion,accounting for 27.08% and 21.43% respectively.HAI rate of different weight groups of neonates in NICU and general wards were both significantly different(χ2＝107.78,46.65,respectively,both P＜0.0001),the lower weight of the neonates,the higher HAI rate;ventilator usage rate in neonates was positively correlated with HAI (r＝0.973,P＝0.027),the higher device usage rate,the higher HAI rate.Fungal septicemia rate per 1 000 days in rainy season was higher than that of non-rainy season (0.53‰ vs 0.37‰).A total of 70 specimens were detected, 45 strains of bacteria and fungi were isolated,pathogens were all from LRT and blood system,Pseudomonas aeru-ginosa was the main pathogen from LRT,Klebsiella pneumoniae and Candida krusei were the main pathogens from blood system.Conclusion Targeted monitoring on neonatal HAI can timely find out high risk factors for neonatal HAI,analyze the causes of infection,formulate corresponding prevention and control measures,reduce HAI rate, and ensure the medical safety of neonates.

Meta analysis on hand hygiene compliance and correct rate among doctors and nurses / 中国感染控制杂志

Objective To systematically evaluate the compliance and correct rate of hand hygiene(HH) among doctors and nurses in secondary and above hospitals in mainland China,and provide data support for HH promotion.Methods Literatures about study on HH in mainland China after 2015 were retrieved from Chinese and English databases,researchers evaluated the literatures according to the relevant standards,screened the qualified literatures and extracted the data strictly according to the inclusion and exclusion criteria,Meta analysis was adopted to analyze the compliance and the correct rate of HH of doctors and nurses in different levels of hospitals and at different departments.Results The overall compliance rate of HH of nurses was higher than doctors,compliance rates of HH of doctors and nurses were 55.9％ (95 ％CI:45.9％,65.8％) and 66.0％ (95％CI:58.8％,73.1％) respectively;HH correct rates of doctors and nurses were 65.2％ (95％CI:53.6％,76.9％) and 67.9％(95％CI:56.9％,78.9％) respectively.Compliance rates of HH of doctors and nurses in tertiary hospitals were both higher than secondary hospitals,compliance and correct rates of HH of doctors and nurses in intensive care unit were both higher than general departments.Conclusion The compliance and correct rate of HH in mainland China need to be further improved,especially the promotion in primary hospitals and general departments.

Internal rib fixation combined with external chest fixation and mechanical ventilation for traumatic flail chest with pulmonary contusion / 中华创伤杂志

Objective To analyze the clinical efficacy of internal rib fixation combined with external chest fixation and mechanical ventilation for traumatic flail chest with pulmonary contusion.Methods Sixty cases of traumatic flail chest with pulmonary contusion treated from January 2011 to December 2014 were assigned to experimental group (30 cases) and control group (30 cases) according to the random number table.Patients in control group received thoracic external fixation combined with mechanical ventilation.In experimental group the patients received the same care but in addition they had rib fixation.The two groups were compared with regard to general condition, arterial blood gas as well as vital signs before treatment and 24 hours after treatment, lung function 3 months after discharge, complication rate and mortality.Results ICU stay [(6.8 ± 1.0) d], hospital stay [(15.0 ± 1.8) d] and duration of mechanical ventilation [(4.8 ± 1.0) d] in experimental group were significantly lower than these in control group [(13.6 ± 2.5) d, (21.4 ± 2.6) d, (10.3 ± 1.3) d, respectively] (P ＜ 0.01).After treatment for 24 hours in either group, the pH value, PaO2, oxygenation index and systolic pressure (SBP) were significantly increased, and partial pressure of carbon dioxide (PaCO2), heart rate (HR) and respiratory rate (RR) were significantly lowered as compared to these before treatment (P ＜0.05).After treatment for 24 hours, experimental group demonstrated significantly enhanced levels in pH value,PaO2, oxygenation index and SBP but lowered levels in PaCO2, HR and RR as compared to control group (P ＜ 0.05).Three months after discharge, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), 75％ forced expiratory flow (FEF75％) and total lung capacity (TLC) in experimental group were (81.7 ±2.6)％, (75.4 ±4.1)％, (83.2 ±4.6)％,(69.1 ±2.3)％, and (88.7 ±3.4)％ respectively, significantly higher than (69.0 ±3.6)％, (71.3 ± 3.9) ％, (78.9 ± 4.3) ％, (62.3 ± 3.3) ％, and (79.0 ± 4.6) ％ respectively in control group (P ＜0.01).In experimental group, there were four cases of pulmonary infection (13％), three pulmonary atelectasis(10％) and one intercostal neuralgia (3％).In control group, there were six cases of pulmonary infection (20％), five pulmonary atelectasis (17％), four intercostal neuralgia (13％) and four thoracocyllosis(13％)(P ＜0.05).There was no significant difference in mortality between the two groups.Conclusion Treatment effect of internal rib fixation for flail chest with pulmonary contusion is improved in combination with mechanical ventilation and external chest fixation.

Current prevalence and correlates of depressive disorder among outpatients with essential hypertension from cardiovascular divisions of tertiary general hospitals / 中国神经精神疾病杂志

Objective To investigate the current prevalence of depressive disorder and the associated factors in pa?tients with essential hypertensive from cardiovascular divisions of tertiary general hospitals. Methods A Chinese version of Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) Axis I Disor?ders was conducted by five mental health professionals on 876 essential hypertensive outpatients at cardiovascular divi?sions of tertiary general hospital. Data on the socio-demographic and clinical characteristics of these hypertensive pa?tients were also collected. Results The current prevalence of depressive disorders among essential hypertensive outpa?tients of tertiary hospitals was 16.6%(145/876). Risk factors for depressive disorders in hypertensive patients included fe?male gender (OR=2.817, 95%CI:1.161~6.885), being 65-year-old and older (OR=1.747, 95%CI:1.118~2.688), non-marital status (OR=2.023, 95%CI:1.203~3.398), gradeⅢhypertension (OR=1.776, 95%CI:1.226~2.333) and car?diovascular diseases (OR=2.018, 95%CI:1.427~2.587). Conclusion Essential hypertensive outpatients, who receive med?ical services at cardiovascular divisions of tertiary general hospital, have high prevalence of depressive disorders. Clini?cians should pay more attention to the mental health of outpatients with essential hypertension.