Mechano-biomimetic hydrogel 3D cell cultivation as a strategy to improve mammalian cell protein expression

Eukaryotic expression systems are frequently employed for the production of recombinant proteins as therapeutics as well as research tools. Among which mammalian cell protein expression approach is the most powerful one, which can express complex proteins or genetic engineered biological drugs, such as PD-1. However, the high expense, which partially derives from its low protein yielding efficiency, limited the further application of such approach in large scale production of target proteins. To address this issue, we proposed a novel technique to promote the protein production efficiency of mammal cells without using conventional genetic engineered approaches. By placing 293T cells in a hydrogel 3D cell culture platform and adjusting the stress relaxation of the matrix hydrogel, cells formed multicellular spheroids by self-organization. In particular, the multicellular spheroids have a significantly enhanced ability to transiently express multiple proteins (SHH-N, PD-1 and PDL-1). We also examined in detail the mechanism underlying this phenomenon, and found that the reorganization of cytoskeleton during spheroids formation enhances the translation process of protein by recruiting ribosomes. Overall, this finding provides a novel approach for subsequent improvement of large-scale mammalian protein expression cell systems.

Identification of cell death-related biomarkers and immune infiltration in ischemic stroke between male and female patients

Background

Stroke is the second leading cause of death and the third leading cause of disability worldwide, with ischemic stroke (IS) being the most prevalent. A substantial number of irreversible brain cell death occur in the short term, leading to impairment or death in IS. Limiting the loss of brain cells is the primary therapy target and a significant clinical issue for IS therapy. Our study aims to establish the gender specificity pattern from immune cell infiltration and four kinds of cell-death perspectives to improve IS diagnosis and therapy.

Methods

Combining and standardizing two IS datasets (GSE16561 and GSE22255) from the GEO database, we used the CIBERSORT algorithm to investigate and compare the immune cell infiltration in different groups and genders. Then, ferroptosis-related differently expressed genes (FRDEGs), pyroptosis-related DEGs (PRDEGs), anoikis-related DEGs (ARDEGs), and cuproptosis-related DEGs (CRDEGs) between the IS patient group and the healthy control group were identified in men and women, respectively. Machine learning (ML) was finally used to generate the disease prediction model for cell death-related DEGs (CDRDEGs) and to screen biomarkers related to cell death involved in IS.

Results

Significant changes were observed in 4 types of immune cells in male IS patients and 10 types in female IS patients compared with healthy controls. In total, 10 FRDEGs, 11 PRDEGs, 3 ARDEGs, and 1 CRDEG were present in male IS patients, while 6 FRDEGs, 16 PRDEGs, 4 ARDEGs, and 1 CRDEG existed in female IS patients. ML techniques indicated that the best diagnostic model for both male and female patients was the support vector machine (SVM) for CDRDEG genes. SVM's feature importance analysis demonstrated that SLC2A3, MMP9, C5AR1, ACSL1, and NLRP3 were the top five feature-important CDRDEGs in male IS patients. Meanwhile, the PDK4, SCL40A1, FAR1, CD163, and CD96 displayed their overwhelming influence on female IS patients.

Conclusion

These findings contribute to a better knowledge of immune cell infiltration and their corresponding molecular mechanisms of cell death and offer distinct clinically relevant biological targets for IS patients of different genders.

[A cross-sectional survey and analysis of the pain status and its influencing factors in diabetic foot ulcer patients]

Objective: To investigate the pain status in diabetic foot ulcer (DFU) patients and analyze its influencing factors. Methods: A single-center cross-sectional survey research method was used. From May 2021 to February 2022, DFU patients who were admitted to the Fourth Medical Center of PLA General Hospital and met the inclusion criteria were selected and investigated. The scores of the heaviest pain, the least pain, the average pain, and the current pain in pain degree and the total score and the scores of influence on patients' daily life, mood, walking ability, daily work, relationship with others, sleep, and life interest in pain-related effects and the total score of patients were evaluated by the brief pain inventory. A self-designed general data questionnaire was used to collect the data including patients' gender, age, education level, body mass index, self-care ability, diabetes course, wound Wagner grade, bacterial culture result of wound specimen, and the levels of glycated hemoglobin, albumin, prealbumin, hemoglobin, and leukocyte count. Patients were classified according to general data, and the total scores of pain degree and pain-related effects were counted. Data were statistically analyzed with Kruskal-Wallis test and Mann-Whitney U test. The indicators with statistically significant differences in univariate analysis were selected for generalized linear model analysis to screen the independent risk factors of pain severity and pain-related effects in DFU patients. Results: A total of 44 questionnaires were sent out, and 42 valid questionnaires were collected, with effective recovery of 95.45%. The scores of the heaviest pain, the least pain, the average pain, and the current pain in DFU patients were 5 (0, 10), 2 (0, 6), 3 (0, 8), and 2 (0, 8), respectively, and the total score of the pain severity was 11 (0, 24); the scores of pain-related effects on patients' daily life, mood, walking ability, daily work, relationship with others, sleep, and life interest were 4 (0, 10), 4 (0, 10), 5 (0, 10), 5 (0, 10), 3 (0, 10), 4 (0, 10), and 4 (0, 10), respectively, and the total score of pain-related effects was 30 (0, 63). In 42 DFU patients, most patients were male, aged 39-87 (67±10) years, most patients had education level of junior high school, most patients had diabetes for more than 20 years, half of patients' wounds were Wagner grade 4, most patients had body mass index and leukocyte count within normal limits, most patients had partial dependence on self-care ability, the bacterial culture results of wound specimen in the vast majority of patients were positive, about half of the patients had abnormal level of albumin, and most patients had abnormal levels of glycosylated hemoglobin, prealbumin, and hemoglobin. Univariate analysis of the above general data showed that total scores of pain severity among patients with different hemoglobin levels and leukocyte counts were statistically significant different (with Z values of -2.05 and -2.55, respectively, P<0.05), and the total scores of pain-related effects on patients with different hemoglobin levels, leukocyte counts, and bacterial culture results of wound specimen were statistically significant different (with Z values of -2.66, -2.02, and -2.12, respectively, P<0.05). Generalized linear model analysis showed that leukocyte count was an independent risk factor for pain severity and pain-related effects in 42 DFU patients (with 95% confidence intervals of 0.28-11.87 and 5.67-36.99, respectively, standardized regression coefficient values of 6.17 and 21.33, respectively, both P values <0.05). The bacterial culture result of wound specimen was an independent risk factor for pain-related effects in 42 DFU patients (with 95% confidence interval of 2.92-39.09, standardized regression coefficient value of 21.00, P<0.05). Conclusions: DFU patients often suffer pain, and the bacterial culture results of wound specimen and leukocyte count are the main factors affecting the pain of DFU patients.

The identification of N6-methyladenosine-related miRNAs predictive of hepatocellular carcinoma prognosis and immunotherapy efficacy

BACKGROUND

Hepatocellular carcinoma (HCC) has a high degree of malignancy and poor prognosis. N6-methyladenosine (m6A) modifications and microRNAs (miRNAs) play pivotal roles in tumorigenesis and development. However, the role of m6A-related miRNAs in HCC has not been clarified yet. This study aimed to identify the role of m6A-miRNAs in HCC prognosis through bioinformatics analysis.

METHODS

The clinicopathological information and RNA sequencing data of 369 HCC tumor tissues and 49 tumor-adjacent tissues were downloaded from the TCGA database. A total of 23 m6A regulators were extracted to evaluated the m6A-related miRNAs using Pearson's correlation analysis. Then, we selected prognosis-related m6A-miRNAs using a univariate Cox regression model and used the consensus cluster analysis to explore the characteristics of the m6A-miRNAs. The coefficient of the least absolute shrinkage and selection operator (LASSO) Cox regression was applied to construct a prognostic risk score model. The receiver operated characteristic (ROC) analysis was applied to evaluate the prognostic value of the signature. The biological functions of targeted genes were predicted by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Then, to validate the potential predictive value for prognosis, the miRNA expression profiles from the GSE76903 and GSE6857 were used. Single sample Gene Set Enrichment Analysis (ssGSEA) and Estimation of Stromal and Immune cells in Malignant Tumor tissues using Expression data (ESTIMATE) were applied to assess the immune microenvironment of HCC. Additionally, a meta-analysis was used to verify the prognostic value of the m6A-microRNAs. RT-PCR was applied to validated the expression of miRNAs in HCC tissues. Cell viability, transwell assay and RNA m6A dot blot assays of HCC cells was applied to access the function of miR-17-5p.

RESULTS

The expression of 48 m6A-related miRNAs was identified and 17 prognostic m6A-miRNAs was discovered. The expression profile of those 17 miRNAs was divided into three clusters, and these clusters were associated with the tumor microenvironment (TME) and prognosis. The nine m6A-related miRNA signature was associated with the prognosis of HCC, the AUC of the ROC was 0.771(TCGA dataset), 0.788(GSE76903) and 0.646(GSE6857). The TME and the expression of immune checkpoint molecules were associated with the risk score. The meta-analysis also validated the prognostic value of the m6A-related miRNAs (miR182-5p (HR:1.58, 95%CI:1.04-2.40) and miR-17-5p (HR:1.58, 95%CI: 1.04-2.40)). The expression of miR-17-5p was upregulated in HCC tissues and miR-17-5p showed an oncogenic role in HCC cells.

CONCLUSION

The clinical innovation is the use of m6A-miRNAs as biomarkers for predicting prognosis regarding immunotherapy response in HCC patients.

[Development and evaluation of a machine learning prediction model for large for gestational age]

Objective: To develop and validate a useful predictive model for large gestational age (LGA) in pregnancy using a machine learning (ML) algorithm and compare its performance with the traditional logistic regression model. Methods: Data were obtained from the National Free Preconception Health Examination Project in China, carried out in 220 counties of 31 provinces from 2010 to 2012, covering all rural couples with a planned pregnancy. This study included all teams of childbearing age who delivered newborns within 24-42 weeks of gestational age and their newborns. Ten different ML algorithms were used to establish LGA prediction models, and the prediction performance of these models was evaluated. Results: A total of 104 936 newborns were included, including 54 856 boys (52.3%) and 50 080 girls (47.7%). The incidence of LGA was 11.7% (12 279). The imbalance between the two groups was addressed by the under- sampling technique, after which the overall performance of the ML models was significantly improved. The CatBoost model achieved the highest area under the receiver-operating-characteristic curve (AUC) value of 0.932. The logistic regression model had the worst performance, with an AUC of 0.555. Conclusions: In predicting the risk for LGA in pregnancy, the ML algorithms outperform the traditional logistic regression method. Compared to other ML algorithms, CatBoost could improve the performance, and it deserves further investigation.

[Effects of orlistat and metformin on metabolism and gonadal function in overweight or obese patients with polycystic ovary syndrome]

The aim of this study was to assess the effects of orlistat or metformin treatment on lipid and glucose metabolism, and gonadal function in obese/overweight women with polycystic ovary syndrome (PCOS). A total of 39 patients diagnosed with PCOS were randomly (digital table method) divided into orlistat treatment group (20 cases) and metformin treatment group (19 cases). Compared with those before, treatment with either orlistat or metformin significantly reduced body weight, body mass index (BMI), hip circumferences, and serum insulin levels of the PCOS patients both at the end of 3 months and 6 months (P<0.05). No significant differences could be viewed between orlistat and metformin treated subjects. Moreover, orlistat treatment significantly lowered the levels of low-density lipoprotein cholesterol, total cholesterol, fasting blood glucose, and homeostasis model assessment-insulin resistance (HOMA-IR) (P<0.05), while there were no significant changes in above parameters with metformin treatment. The improvement of menstrual cycle was observed after 6-month treatment in both groups (P<0.05). However, changes in polycystic ovarian morphology by ultrasound were only observed in orlistat treated group. In conclusion, orlistat is comparable with metformin in weight loss and improvement of insulin resistance and menstrual cycle, and is superior to metformin in improvement of lipid metabolism in overweight/obese PCOS patients.

[Changes in platelet related parameters in obese patients after sleeve gastrectomy]

To compare changes in platelet related parameters in obese patients before and after sleeve gastrectomy (SG), we retrospectively analyzed the clinical data of 31 obese patients who underwent SG in Peking Union Medical College Hospital from December 2012 to September 2020. Results showed that compared with those before surgery, platelet count (PLT) decreased significantly at 2-12 weeks of follow-up (P=0.009), while platelet distribution width (PDW), mean platelet volume (MPV), and large platelet ratio (P-LCR) increased significantly at the same periods of follow-up after operation (P<0.001). However, the levels of PDW, MPV, and P-LCR began to decrease at 16-55 weeks when compared with those at 2-12 weeks of follow-up (P<0.01). PLT was positively correlated with white blood cells and neutrophils at 2-12 weeks of follow-up and positively correlated with high sensitivity C-reactive protein at 16-55 weeks of follow-up after operation (P<0.05).

[Updated key points of Chinese Consensus for the Diagnosis and Treatment of Acromegaly (2021 edition)]

Led by the China Pituitary Adenoma Specialist Council, the Chinese Consensus for the Diagnosis and Treatment of Acromegaly (2021 Edition) is developed combined with the research progress of pituitary growth hormone (GH)-secreting adenoma both at home and abroad, evidence-based evidence of the diagnosis and treatment of acromegaly, and China's national conditions. Based on the guideline for acromegaly (2013 Edition), the new version of consensus emphasizes the importance of multidisciplinary team (MDT) and individual therapy. The criteria for control of acromegaly is discussed. Pathological criteria for the diagnosis of pituitary GH-secreting adenoma is updated. New developments in surgery, drug and radiotherapy are introduced. Meanwhile, the diagnosis and treatment of acromegaly patients concurrent with other particular scenarios, including pregnancy and refractory pituitary GH-secreting adenoma is suggested. This article aims to describe the updated key points of the new version of the consensus, and thus facilitate the clinical implementation of standardized diagnosis and treatment for acromegaly patients.

MyD88 determines the protective effects of fish oil and perilla oil against metabolic disorders and inflammation in adipose tissue from mice fed a high-fat diet

BACKGROUND

The beneficial effects of ω-3 polyunsaturated fatty acids (PUFA) vary between different sources. However, there is a paucity of comparative studies regarding the effects and mechanisms of marine and plant ω-3 PUFA on obesity.

OBJECTIVE

The aim of this study was to evaluate the effects of fish oil (FO) and perilla oil (PO) on glucolipid metabolism, inflammation, and adipokine in mice fed a high-fat (HF) diet in association with the contribution of toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88) pathway.

METHODS

C57BL/6J mice and MyD88-/- mice were randomly divided into 4 groups: normal chow diet, HF diet, HF diet accompanied by daily gavage with either FO or PO. After 4 weeks, blood biochemistries, adipocyte histology, mRNA, and protein expression of MyD88-dependent and -independent pathways of TLR4 signaling in epididymal adipose tissue were measured.

RESULTS

In C57BL/6J mice, there were no statistical differences between FO and PO in decreasing body weight, glucose, insulin, triglyceride, total cholesterol, interleukin-6, and increasing adipocyte counts. FO and PO decreased mRNA and protein expression of TLR4, MyD88, tumor necrosis factor receptor-associated factor 6, inhibitor of nuclear factor kappa B kinase beta and nuclear factor-kappa B p65. In MyD88-/- mice, the beneficial effects of FO and PO on HF diet-induced metabolism abnormalities and inflammation were abolished. FO and PO had no impacts on mRNA and protein expression of receptor-interacting protein-1, interferon regulate factor 3, and nuclear factor-kappa B p65.

CONCLUSION

FO and PO exhibit similar protective effects on metabolic disorders and inflammation through inhibiting TLR4 signaling in a manner dependent on MyD88. These findings highlight plant ω-3 PUFA as an attractive alternative source of marine ω-3 PUFA and reveal a mechanistic insight for preventive benefits of ω-3 PUFA in obesity and related metabolic diseases.

MicroRNA-224 modulates chemosensitivity of breast cancer cells to docetaxel by apoptosis inhibitor 5

PURPOSE

The view that microRNA-224 (miR-224) may lead to tumorigenesis has been accepted in many studies. However, its role remains unclear in modulating the chemosensitivity of breast cancer cells to docetaxel (DOC). Thus, the aim of this study was to estimate what's the role of miR-224 in the chemosensitivity of breast cancer cells to DOC.

METHODS

The role of miR-224 in breast cancer cells was analyzed using CCK-8 assay, real-time PCR, flow cytometry assay and Western blot. Dual-luciferase reporter assay and API-5-siRNA technology were performed to analyze the association between miR-224 and Apoptosis inhibitor 5 (API-5).

RESULTS

Overexpression of miR-224 could significantly decrease the chemosensitivity of MCF-7 breast cancer cells to DOC. The luciferase activity of MCF-7/DOC cells containing wild-type 3'UTR of API-5 could be inhibited by miR-224 mimics. Similarly, the chemoresistance of MCF-7 cells to DOC induced by miR-224 mimics could be partially reversed by API-5-siRNA.

CONCLUSION

An inverse association between miR-224 and API-5 in breast cancer cells was revealed. Dysregulation of miR-224 plays a vital role in the acquired DOC resistance of breast cancer and at least partially via targeting API-5.

[Association of sleep duration with cognitive impairment among older adults aged 65 years and older in China]

Objective: The study is to examine association of sleep duration and cognitive impairment in the older adults aged 65 years and older in China. Methods: We analyzed data from 2017-2018 wave of Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 14 966 participants were included in the analysis. Data with respect to socioeconomic status, community involvement, behavior pattern, diet, life style, family structure, disease condition, mental health and cognitive function were collected. Cognitive function was measured with Mini-mental State Examination (MMSE). We conducted generalized linear mixed models to examine associations of sleep duration with cognitive impairment, and subgroup analyses of sex and age were conducted. Results: Among 14 966 participants, the percentage of participants aged 65 to 79 years, 80 to 89 years, 90 to 99 years and 100 years and older was 5 148 (4.40%), 3 777 (25.24%), 3 322 (22.20%) and 2 719 (18.16%), respectively. A total of 2 704 participants reported sleep duration of 5 h and less, and 3 883 reported 9 h and more, accounting for 18.94% and 27.19%, respectively. In total, 3 748 were defined with cognitive impairment, accounting for 25.04%. The results of generalized linear mixed models showed that both short (≤5 h) and long (≥ 9 h) sleep duration were associated with cognitive impairment compared with sleep duration of 7 h, with OR(95%CI) of 1.35(1.09-1.68) and 1.70(1.39-2.07), respectively. The association of sleep duration with cognitive impairment was more obvious in males and individuals aged 65 to 79 years old. Conclusion: Short or long sleep duration was responsible for increased risk of cognitive impairment in older Chinese.

Different effects of high-fat diets rich in different oils on lipids metabolism, oxidative stress and gut microbiota

The study aimed to investigate the different effects of high-fat (HF) diets rich in different oils on lipid metabolism, oxidative stress, and gut mirobiota. C57BL/6 mice were divided into 4 groups: (1) control group (CG) was fed with normal diet, (2) olive oil (OO) group was fed with high-fat diet containing OO, (3) lard oil (LO) group was fed with high-fat diet containing LO, (4) soybean oil (SO) group was fed with high-fat diet containing SO. After 12 weeks, serum lipids, and oxidative stress indices were analyzed. Gut microbiota analysis was carried out based on the sequencing results of 16S rRNA. High fat diet can increase serum and liver lipids and upregulate sterol regulatory element-binding protein-1c related genes expression. Serum and liver malondialdehyde (MDA) levels in LO group were significantly higher than those in CG and OO groups. In CG, the family Muribaculaceae, Lactobacillaceae, Lachnospiraceae and Desulfovibrionaceae had the large effect sizes. HF diets resulted in the increase of Actinobacteria and Enterococcaceae abundance, and the decrease of Bacteroidetes, Proteobacteria Lactobacillales and microbiota diversity. The abundance of Actinobacteria and Lactobacillales is the link to the serum TC and MDA levels. HF diets have the harmful influence on the serum lipids, oxidative stress and endothelial function. They can also cause gut microbiota dysbiosis.

[Mechanism study of dendritic epidermal T lymphocytes in promoting healing of full-thickness skin defects wound on mice by regulating the proliferation and differentiation of epidermal stem cells in mice]

Objective: To explore the mechanism of dendritic epidermal T lymphocytes (DETCs) in promoting healing of full-thickness skin defect wound on mice by regulating the proliferation and differentiation of epidermal stem cells (ESCs) in mice. Methods: (1) Ten 8-week-old wild type (WT) male C57BL/6 mice (the same sex and kind below) were sacrificed to collect the skin of back for extracting DETCs to culture. Five WT and five 8-week-old T cell receptor (TCR) δ(-)/(-) mice were selected and enrolled in WT control group and TCR δ(-)/(-) control group, respectively. A full-thickness skin defect wound with diameter of 6 mm was made on both sides of spinal line on the back of mice without any treatment after injury. Another fifteen 8-week-old TCR δ(-)/(-) mice were selected and divided into phosphate buffer solution (PBS), DETC, and insulin-like growth factor-Ⅰ(IGF-Ⅰ) groups according to the random number table (the same grouping method below), with 5 mice in each group, and the same full-thickness skin defect wound was made on each mouse. Immediately after injury, mice in PBS, DETC, and IGF-Ⅰ groups were injected subcutaneously around each wound with 10 μL sterile PBS , DETCs (cell concentration of 1×10(6)/mL), and 5 mg/mL recombinant mice IGF-Ⅰ, respectively. The percentage of the residual wound area was calculated on post injury day (PID) 2, 4, 6, and 8. (2) Three 8-week-old WT mice were enrolled in WT control group and nine 8-week-old TCR δ(-)/(-) mice were divided into TCR δ(-)/(-) control group, PBS group, and DETC group, with 3 mice in each group. The full-thickness skin defect wound was made as in experiment (1) . On PID 3, the protein expression of IGF-Ⅰ in the epidermis tissue of wound margin was detected by chemiluminescence imaging analyzer. (3) Three 8-week-old WT mice were enrolled in WT control group and six 8-week-old TCR δ(-)/(-) mice were divided into PBS and DETC groups, with 3 mice in each group, and the full-thickness skin defect wound was made as in experiment (1). On PID3, DETCs were extracted from the wound margin epidermis tissue to detect the percentage of DETCs expressing IGF-Ⅰ by flow cytometer. (4) The mice were taken as in experiment (2) and divided into WT control, PBS, DETC, and IGF-Ⅰ groups. A straight full-thickness skin defect incision with length of 3 cm was made in the direction of one inner ear. Mice in WT control group didn't have any other treatment after injury, and immediately after injury, mice in PBS, DETC, and IGF-Ⅰ groups were injected subcutaneously around each wound with 10 μL sterile PBS, DETCs (cell concentration of 1×10(6)/mL), and 5 mg/mL recombinant mice IGF-Ⅰ, respectively. On PID 12, epidermis tissue of wound margin was collected, and immunofluorescence staining was performed to observe the number of keratin 15 positive cells. (5) The same mice were collected, grouped, and treated as in experiment (4). On PID12, the epidermis tissue of wound margin was collected and immunofluorescence staining was performed to observe the number of keratin 10 positive cells. (6) Twenty 3-day-old WT mice (the same below) were sacrificed to collect the whole skin, which was used to extract ESCs, with 5 mice detecting one index. The ESCs were divided into DETC co-culture group and control group, which were added with 1 mL DETCs (cell concentration of 1.25×10(6)/mL) and DETC medium, respectively. The percentage of 5-ethynyl-2'-deoxyuridine (EdU) positive cell on culture day (CD) 3, the percentages of CD49f(+) CD71(-) and keratin 14 positive cells on CD 5, and the percentage of keratin 10 positive cell on CD 10 in 2 groups were detected by flow cytometer. (7) Twenty mice were taken to extract ESCs, with 5 mice detecting one index. The ESCs were divided into control group and IGF-Ⅰ group, which were added with 1 mL sterile PBS and 10 ng/mL recombinant mice IGF-Ⅰ, respectively. The percentages of EdU positive cell, CD49f(+) CD71(-) cell, keratin10 positive cell, and keratin 14 positive cell were detected as in experiment (6). The sample in each group of experiments (6) and (7) was three. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, and t test. Results: (1) On PID 4, 6, and 8, the percentage of residual wound area in TCR δ(-)/(-) control group was significantly higher than that in WT control group (t=2.78, 3.39, 3.66, P<0.05 or P<0.01). The percentage of residual wound area in DETC group and IGF-Ⅰgroup on PID 4, 6, and 8 was apparently lower than that in PBS group (t=2.61, 3.21, 3.88, 2.84, 2.91, 2.49, P<0.05 or P<0.01). (2) On PID 3, the protein expression of IGF-Ⅰ in the epidermis tissue of wound margin of mice in TCR δ(-)/(-) control group was significantly lower than that in WT control group (t=17.34, P<0.01). The protein expression of IGF-Ⅰ in the epidermis tissue of wound margin of mice in DETC group was significantly higher than that in PBS group (t=11.71, P<0.01). (3) On PID 3, the percentage of DETCs expressing IGF-Ⅰ in the epidermis tissue of wound margin of mice in PBS group was significantly lower than that in WT control group and DETC group (t=24.95, 27.23, P<0.01). (4) On PID 12, the number of keratin 15 positive cells in the epidermis tissue of wound margin of mice in PBS group was significantly lower than that in WT control group, DETC group, and IGF-Ⅰ group (t=17.97, 11.95, 7.63, P<0.01). (5) The number of keratin 10 positive cells in the epidermis tissue of wound margin of mice in PBS group was significantly higher than that in WT control group, DETC group, and IGF-Ⅰ group (t=11.59, 9.51, 3.48, P<0.05 or P<0.01). (6) The percentages of EdU positive cells on CD 3, CD49f(+) CD71(-) cells on CD 5, and keratin 14 positive cells on CD 5 in DETC co-culture group were respectively (43.5±0.6)%, (66.5±0.5)%, (69.3±1.7)%, apparently higher than (32.3±1.3)%, (56.4±0.3)%, (54.9±1.3)% in control group (t=7.97, 17.10, 6.66, P<0.01). The percentage of keratin 10 positive cells on CD 10 in DETC co-culture group was (55.7±0.7)%, significantly lower than (67.1±1.2)% in control group (t=8.34, P<0.01). (7) The percentages of EdU positive cells on CD 3, CD49f(+) CD71(-) cells on CD 5, and keratin 14 positive cells on CD 5 in IGF-Ⅰ group were respectively (42.1±0.9)%, (81.1±1.3)%, (66.8±1.0)%, apparently higher than (32.4±0.7)%, (74.9±0.7)%, (52.0±1.9)% in control group (t=8.39, 4.24, 7.25, P<0.05 or P<0.01). The percentage of keratin 10 positive cells on CD 10 in IGF-Ⅰ group was (53.5±1.1)% , significantly lower than (58.2±0.3)% in control group (t=3.99, P<0.05). Conclusions: DETCs can promote the proliferation and anti-apoptotic potential of ESCs and inhibit their differentiation into end-stage by secreting IGF-Ⅰ, thus promoting wound healing of full-thickness skin defects in mice.

[Impact of history of hypertension and blood pressure levels on the risk of thromboembolism in nonvalvular atrial fibrillation patients]

Objective: To investigate the impact of history of hypertension and blood pressure levels on the thromboembolism risk in the setting of nonvalvular atrial fibrillation (NVAF). Methods: China Atrial Fibrillation Registry Study prospectively enrolled 25 512 atrial fibrillation (AF) patients between August 2011 and December 2018. After exclusion of patients with valvular AF, hypertrophic cardiomyopathy, receiving anticoagulation or ablation therapy at the enrollment, 7 757 patients were included in analysis. The primary endpoint was the time to the first occurrence of ischemic stroke or systemic embolism. Cox proportional hazards models were performed to evaluate whether a history of hypertension or blood pressure levels were independently associated with thromboembolism. Results: During a mean follow up of (35±25) months, 455 （5.9%）thromboembolic events occurred. The crude incidence rate of thromboembolism in patients with a history of hypertension was higher than that in patients without hypertension (2.38 vs. 1.35 per 100 patient-years, χ²=16.8，Log-rank P<0.001). Patients were further divided into 4 groups according to systolic blood pressure (SBP) levels at baseline, the crude incidence rate of thromboembolism significantly increased in proportion to the elevation of SBP levels (χ²=17.9，Log-rank P<0.001). However, there was no significant difference in thromboembolism risk among 4 groups stratified by diastolic blood pressure (DBP) levels (χ²=0.6，Log-rank P=0.907). Multivariable regression analysis showed that history of hypertension was independently associated with a 27% higher risk of thromboembolism (HR=1.27, 95%CI 1.01-1.61, P=0.045). Patients with SBP≥140 mmHg (1 mmHg=0.133 kPa) was associated with 36% higher risk of thromboembolism than patients with SBP<120 mmHg (HR=1.36, 95%CI 1.02-1.82, P=0.036). However, patients with SBP 120-129 mmHg or 130-139 mmHg were not at a higher risk of thromboembolism as compared to the patients with SBP<120 mmHg (SBP 120-129 mmHg: HR=1.23, 95%CI 0.90-1.67, P=0.193; SBP 130-139 mmHg: HR=1.30, 95%CI 0.95-1.77, P=0.098). In addition, DBP levels were not independently associated with the increased thromboembolism risk. Conclusion: A history of hypertension and SBP≥140 mmHg are independent predictors of thromboembolism risk in patients with NVAF. These results indicate that intensive efforts to lower SBP below 140 mmHg might be an important strategy to reduce the risk of stroke in patients with NVAF.

[Risk factors for postoperative intestinal obstruction in patients undergoing robot-assisted laparoscopic radical prostatectomy]

Objective: To analyze the risk factors of postoperative intestinal obstruction (POI) in patients undergoing robot-assisted laparoscopic radical prostatectomy (RARP). Methods: The clinical data of 573 patients receiving RARP from January to December 2019 in Nanjing Drum Tower Hospital were analyzed retrospectively. According to the occurrence of POI, the cases were divided into the occurrence group and the non-occurrence group. The clinical data of the two groups were compared and the risk factors of POI were investigated by multivariate logistic regression. Results: Forty-five of 573 patients (7.9%) had POI. Between the two groups, preoperative underlying diseases (cardiopathy, COPD, hypoalbuminemia), preoperative chemotherapy, preoperative WBC, operation time, blood loss, blood transfusion rate, postoperative early fever, length of stay were statistically significant (P<0.05). Multivariable logistic regression analysis showed that heart disease (OR=2.331, P=0.036), COPD (OR=4.285, P=0.001), hypoalbuminemia(OR=2.142, P=0.026), blood loss (≥4.26 ml/kg) (OR=2.388, P=0.010), operative time (≥225 min) (OR=4.200, P<0.001), and postoperative early fever (OR=2.773, P=0.004) were independent risk factors for POI after RARP. Conclusions: The incidence of POI following RARP is related to multiple perioperative factors. Improving the preoperative heart and lung function, correcting hypoalbuminemia, reducing intraoperative bleeding, shortening the operation time, and preventing early postoperative infection may be important measures to reduce the risk of POI in RARP patients.

The validation of a questionnaire to delineate clinical research coordinator roles in China

PURPOSE

The purpose of this study was to evaluate the roles of the clinical research coordinator (CRC) in clinical oncology trials.

DESIGN AND METHODS

An E-questionnaire that includes 10 sections with 155 items total and is based on the Clinical Trials Nursing Questionnaire (CTNQ) was designed to determine the conditions of demographics, competences, activities, and psychology for Chinese CRCs. Eighty-two CRCs from three different provinces in China were invited to join this study anonymously. Cronbach's α and split-half reliability were calculated to assess the reliability and validity of the questionnaire. Additionally, the Wilcoxon rank-sum test was used to find the similarity and difference between the importance of the roles of CRCs and their frequency. The STROBE checklist for observational research has been following for presenting the research (see File S1).

FINDINGS

Cronbach's α values of the Chinese version of the questionnaire for the frequency scale and the importance scale were .965 and .961, respectively. The split-half reliability coefficients were 0.866 and 0.805, respectively. Pearson correlation coefficients of the subscales indicated that the correlation between each item and its dimension was greater than its correlation with the other components (P < .05). Exploratory factor analysis results show that three common factors were extracted by principal component analysis and had eigenvalues greater than 1 and that the cumulative contribution rate was 69.415%.

PRACTICE IMPLICATIONS

The Chinese version of the questionnaire has good reliability and validity for CRCs in China, which could be promoted in evaluating clinical research coordinator roles in China.

[Etiology and clinical features of primary adrenal insufficiency]

Objective: To summarize the etiology of primary adrenal insufficiency (PAI) and analyze its clinical features. Methods: A retrospective analysis was performed in the Department of Endocrinology, Peking Union Medical College Hospital from October 1981 to June 2019. Patients with PAI as the first symptom were enrolled. The etiology of PAI was analyzed and the clinical characteristics was also summarized. Results: A total of 131 patients with PAI were enrolled, including 87 males and 44 females (57 adolescents, and 74 adults). The age ranged from 0 to 73 years. The primary cause of PAI in adolescents was genetic defects (52.6%, 30/57), in which congenital adrenal dysplasia caused by DAX1 gene deficiency accounted for 50.0% (15/30), followed by autoimmunity (22.8%, 13/57). The primary cause of adult PAI was infection (58.1%, 43/74), of which tuberculosis accounted for the majority (93.0%, 40/43), and autoimmune adrenalitis accounted for 19.0% (14/74). Compared with the tuberculosis group, female patients were more common, and the onset age was younger, the plasma cortisol, serum sodium, fasting blood glucose, creatinine and aldosterone were lower (all P<0.05), and serum potassium and renin levels were higher in the autoimmune adrenalitis group (both P<0.05). Conclusions: In the current study, the proportion of PAI caused by infection in the adult group was higher than that in the adolescent group. The most common cause of adult PAI was tuberculosis infection. The most common cause of childhood PAI was genetic defects. Autoimmune damage to the adrenal glands may be more severe than tuberculosis infection.

[Relationship between C-reactive protein level and incidence of left atrial spontaneous echocardiographic contrast in patients with nonvalvular atrial fibrillation]

Objective: To investigate the relationship between high sensitivity C-reactive protein (hs-CRP) level and incidence of left atrial spontaneous echocardiographic contrast (LASEC) in the patients with nonvalvular atrial fibrillation (AF). Methods: Four hundred and ninety consecutive patients with nonvalvular atrial fibrillation who underwent radiofrequency ablation for the first time from January 1, 2018 to June 30, 2018 in the Department of Cardiology, Beijing Anzhen Hospital were enrolled. According to the results of transesophageal echocardiography before radiofrequency ablation, patients were divided into the group without LASEC (n=338) and the group with LASEC (n=152). hs-CRP was determined by latex enhanced immunoturbidimetry. The relationship between hs-CRP and LASEC in patients with nonvalvular atrial fibrillation was investigated by univariate and multivariate logistic analysis. Results: LASEC was detected in 152 (31%) of 490 patients. Significant differences in age, type of atrial fibrillation, previous embolic events, fibrinogen, D-dimer, the left atrial anteroposterior diameter and CHA(2)DS(2)-VASc scores were found between patients with and without LASEC (all P<0.05). Compared with the group without LASEC, the serum hs-CRP level was significantly higher in the group with LASEC (3.16 (1.30, 5.23) mg/L vs. 0.67 (0.37, 1.48) mg/L, P<0.001). Multivariate logistic regression analysis showed that hs-CRP (OR=1.136, 95%CI 1.060 - 1.217, P<0.001) and D-dimer (OR=1.040, 95%CI 1.011 - 1.070, P=0.007) were independent determinants for LASEC in this patient cohort. Conclusions: hs-CRP is an independent determinant for LASEC in patients with nonvalvular atrial fibrillation. Inflammation may thus be involved in the formation of prethrombotic state in patients with nonvalvular atrial fibrillation.

[Effects of dendritic epidermal T cells on proliferation and apoptosis of epidermal cells in wound margin of mice]

Objective: To explore the effects of dendritic epidermal T cells (DETC) on proliferation and apoptosis of epidermal cells in wound margin of mice and its effects on wound healing. Methods: Twenty-eight healthy specific pathogen free (SPF) C57BL/6 wild-type (WT) male mice aged 8-12 weeks and 60 SPF T lymphocyte receptor δ-knockout (TCR δ(-/-)) male mice aged 8-12 weeks were selected to conduct the following experiments. (1) Eight WT mice were selected to isolate epidermal cells and primarily culture DETC according to the random number table. Morphological observation and purity identification of DETC by flow cytometer were detected immediately after culture and on culture day (CD) 15 and 30, respectively. (2) According to the random number table, 5 WT mice and 5 TCR δ(-/-) mice were selected and enrolled into WT control group and TCR δ(-/-) group. Round full-thickness skin defect with diameter of 6 mm was made on the back of each mouse. The wound healing condition was observed immediately after injury and on post injury day (PID) 2, 4, 6, 8, 10, and the percentage of residual wound area was calculated. (3) Mice were selected to group and reproduce model of full-thickness skin defect as in experiment (2). On PID 3, the tissue of wound margin was collected for hematoxylin eosin staining, and the length of new epithelium was measured. (4) Mice were selected to group and reproduce model of full-thickness skin defect as in experiment (2). On PID 3, epidermal tissue of wound margin was collected to determine expression of proliferating cell nuclear antigen (PCNA) using Western blotting for evaluation of proliferation of epidermal cell. (5) Mice were selected to group and reproduce model of full-thickness skin defect as in experiment (2). On PID 3, epidermal tissue of wound margin was selected and digested into single-cell suspension, and apoptosis of cells was detected by flow cytometer. (6) Forty TCR δ(-/-) mice were selected to carry out the same treatment as in experiments (2)-(5). According to the random number table, these mice were enrolled into TCR δ(-/-) control group and TCR δ(-/-)+ DETC group, with 5 mice in each group for each experiment. Round full-thickness skin defect was made on the back of each mouse. DETC in the number of 1×10(5) (dissolution in 100 μL phosphate with buffer purity above 90%) were injected through multiple points of wound margin of mice in TCR δ(-/-)+ DETC group immediately after injury, and equal volume of phosphate buffer was injected into mice of TCR δ(-/-) control group with the same method as above. Data were processed with one-way analysis of variance for repeated measurement, t test, and Bonferroni correction. Results: (1) Along with the culture time elapse, the number of dendritic structures of DETC increased gradually. The percentage of T lymphocytes was 4.67% and 94.1% of these T lymphocytes were DETC. The purity of DETC on CD 15 was 18.50% and the purity of DETC on CD 30 was 98.70%. (2) Immediately after injury, the wound healing condition of mice in WT control group and TCR δ(-/-) group was similar. The wound healing speed of mice in TCR δ(-/-) group was slower than that in WT control group on PID 2-10. The percentages of residual wound area of mice in TCR δ(-/-) group on PID 2, 4, 6, 8, and 10 were increased significantly compared with those in WT control group (t=3.492, 4.425, 4.170, 4.780, 7.318, P<0.01). (3) The length of new epithelium of mice in TCR δ(-/-) group on PID 3 was (359 ± 15) μm, which was obviously shorter than that in WT control group [(462±26) μm, t=3.462, P<0.01]. (4) Immediately after injury, wound condition of mice in TCR δ(-/-)+ DETC group and TCR δ(-/-) control group was similar. Compared with TCR δ(-/-)+ DETC group, the wound healing speed of mice in TCR δ(-/-) control group were obviously slower on PID 2-10. The percentages of residual wound area of mice in TCR δ(-/-)+ DETC group on PID 2, 4, 6, 8, and 10 were decreased significantly compared with those in TCR δ(-/-) control group (t=2.308, 3.725, 2.698, 3.707, 6.093, P<0.05 or P<0.01). (5) On PID 3, the length of new epithelium of mice in TCR δ(-/-)+ DETC group was (465±31) μm, which was obviously longer than that in TCR δ(-/-) control group [(375±21) μm, t=2.390, P<0.05]. (6) On PID 3, PCNA expression of epidermal cell in wound margin of mice in TCR δ(-/-) group was 1.25±0.04, which was obviously lower than that in WT control group (2.01±0.09, t=7.415, P<0.01). (7) On PID 3, PCNA expression of epidermal cell in wound margin of mice in TCR δ(-/-)+ DETC group was 1.62±0.08, which was significantly higher than that in TCR δ(-/-) control group (1.05±0.14, t=3.561, P<0.05). (8) On PID 3, apoptosis rate of epidermal cell in wound margin of mice in TCR δ(-/-) group was (16.1±1.4)%, which was higher than that in WT control group [(8.1±0.6)%, t=5.363, P<0.01]. (9) On PID 3, apoptosis rate of epidermal cell in wound margin of mice in TCR δ(-/-)+ DETC group was (11.4±1.0)%, which was obviously lower than that in TCR δ(-/-) control group [(15.4±1.4)%, t=2.377, P<0.05]. Conclusions: DETC participates in the process of wound healing though promoting the proliferation of epidermal cells in wound margin and inhibit the apoptosis of these cells.

Effects of palm olein and olive oil on serum lipids in a Chinese population: a randomized, double-blind, cross-over trial

BACKGROUND AND OBJECTIVES

As the most widely produced edible vegetable oil, palm oil is known as to contain a high level of saturated fatty acid, which was thought to adversely affect serum lipid profiles. However, recent studies have shown no influence or benefits of palm oil on serum lipids. The potential nutritional value of palm oil is attributed to the high mono-unsaturation at the crucial sn2-position of the oil's triacylglycerols, as with the so-called 'healthy' olive oil (OO). The aim of this study was to further test this hypothesis and evaluate the effects of consuming palm olein versus olive oil on serum lipid profiles in a Chinese population.

METHODS AND STUDY DESIGN

In total, 120 participants were recruited from a spinnery in Yixing city and randomly divided into two groups (palm olein or olive oil) to conduct a 2×2 crossover trial for 2 months' intervention with 2-week washout periods. Each participant was provided 48 g of test oil per day. At the end of each period, anthropometry, and blood lipid indices were measured to determine the effects of palm olein and olive oil.

RESULTS

Palm olein and olive oil consumption had no significantly different effect on BMI, on serum total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triacylglycerol (TG), Apo B, fasting glucose, or insulin concentrations (all p>0.05).

CONCLUSIONS

In a dietary crossover trial, palm olein and olive oil had no recognisably different effects on body fatness or blood lipids in a healthy Chinese population.

[The correlation of ganglion cell layer thickness with visual field defect in non-functional pituitary adenoma with chiasm compression]

Objective: To investigate the consequences of the thickness of ganglion cell layer (GCL) and visual field defect of non-functional pituitary adenoma with chiasm compression. Methods: A case control study. The study included 40 (80 eyes) non-functional pituitary adenoma patients in Peking Union Medical College Hospital from March 2015 to February 2017. Twenty patients (no visual field defect group, 40 eyes) of them were detected to be chiasm compressed or touched by the adenoma with no visual field defect detected, and the other 20 patients (visual field defect group, 40 eyes) were the sex-and-age matched pituitary adenoma patients with bitemporal heminopsia. This study also included 20 (control group, 40 eyes) sex-and-age matched healthy controls. The para-papillary retinal nerve fiber layer (RNFL) thickness in 6 quadrants including nasal, temporal, nasal superior, temporal superior, nasal inferior and temporal inferior as well as the macular GCL thickness and ganglion cell-inner plexiform layer (GCIPL) thickness in 4 quadrants including nasal superior, nasal inferior, temporal superior and temporal inferior were measured. The non-parametric test was used to compare the RNFL, GCL and GCIPL thickness among the three groups. Results: The mean age among the three groups was (46±10) years and the difference among the three groups was not significant (P=0.88). The sex ratio of the three groups was 9∶11 (male∶female) and the difference among the three groups was not significant. The mean axial length among the three groups was (23.22±0.90) mm and the difference among the three groups was not significant (P=0.51). The thickness of para-papillary RNFL of temporal superior, temporal, nasal superior, nasal, nasal inferior quadrants and whole circumference was significantly thinner in the visual field defect group than the control group [(129.88±28.64) μm, (63.63±26.84) μm, (88.08±32.16) μm, (50.68±19.99) μm, (92.48±25.06) μm, and (85.00±20.65) μm vs. (141.10±18.95) μm, (79.12±16.78) μm, (113.68±21.28) μm, (69.67±14.23) μm, (117.80±31.32) μm, and (102.80±9.68) μm, t=2.26, 3.06, 4.14, 4.84, 4.25, 4.88, all P<0.05]. In the nasal quadrant, the para-papillary RNFL of the no visual field defect group was significantly thinner compared with the control group [(61.45±9.83) μm vs. (69.67±14.23) μm, t=2.97, P<0.05]. The total GCL thickness was (30.48±5.42) μm in the visual field defect group, (31.35±2.77) μm in the no visual field defect group, thinner than that in the control group [(33.32±2.92) μm, t=2.92, 3.62; both P<0.05]. The total GCIPL thickness showed no significant difference among the three groups (P=0.07). In the superior and inferior temporal quadrants, the GCL and GCIPL thickness showed no significant difference among the three groups (all P>0.05). In the superior and inferior nasal quadrants, the GCL thickness was (29.41±5.97) μm, and (28.47±5.13) μm in the visual field defect group, (31.15±3.27) μm and (30.61±2.96) μm in the no visual field defect group, and (34.23±3.16) μm and (32.97±2.78) μm in the control group. The GCL thickness in the nasal quadrant was thinner in the visual field defect group (t=4.45, 4.82)and the no visual field defect group(t=4.23, 3.63) than in the control group (all P<0.01). However, no significant difference in GCL thickness was detected between the visual field defect group and the no visual field defect group (both P>0.05). In the superior and inferior nasal quadrants, the GCIPL thickness was (54.06±10.50) μm and (51.77±9.18) μm in the visual field defect group, (58.03±4.00) μm and (56.23±5.37) μm in the no visual field defect group, and (62.26±7.11) μm and (59.39±6.64) μm in the control group. The GCIPL thickness was thinner in the nasal quadrant in the visual field defect group than in the control group (t=3.95, 4.20, both P<0.01). Only in the Superior nasal quadrant, the GCIPL was significantly thinner in the no visual field defect group than the control group (t=3.25, P<0.01). Conclusion: The optic GCL may get thinner in pituitary nonfunctional adenoma with chiasm compression patients without the RNFL layer thinning and visual field defect. (Chin J Ophthalmol, 2019, 55: 186-194).

[Cross-sectional survey of life quality of patients with deep partial-thickness and above burns on head and face at discharge and analysis of its influencing factors]

Objective: To study the quality of life and its influencing factors of patients with deep partial-thickness and above burns on head and face at discharge, and to guide clinical nurses to provide targeted nursing for patients. Methods: A cross-sectional survey was conducted on 42 patients with deep partial-thickness and above burns on head and face who met the inclusion criteria. The patients were hospitalized from January 2014 to November 2017 in the Department of Burns and Plastic Surgery of our hospital and were selected by adopting the convenient sampling method. On the day before discharge, the Chinese version of the Abbreviated Burn Specific Health Scale was used to assess the scores in various fields of patients' quality of life and total scores. The self-designed general situation questionnaire was used to investigate the gender, age, education level, occupation, marital status, cause of injury, and source of expenses of patients, and the scores in various fields of quality of life of patients in various general conditions and total scores were recorded. Data were processed with t test or one-way analysis of variance. The indicators with statistically significance in the total score difference in the above analysis were chosen, and multivariate linear regression analysis was performed to screen the factors influencing the quality of life of patients. Results: Totally 42 groups of questionnaires were sent out and 42 groups of valid questionnaires were retrieved. The effective recovery rate was 100%. The total score of quality of life of patients at discharge was (49±10) points. The scores of general health status (57±23) points, social relations (56±18) points, physical function (49±17) points, and mental health (41±20) points were ranked from high to low. There were statistically significant differences in the scores of physical function, mental health, and general health status among patients of different age groups (F=8.115, 14.182, 19.285, P<0.01). There were statistically significant differences in the scores of mental health, social relations, and general health status among patients with different educational levels (F=3.312, 51.176, 21.852, P<0.05 or P<0.01). There were statistically significant differences in the scores of mental health and general health status among patients with different occupations (F=3.667, 2.947, P<0.05). The scores of mental health and social relations of married patients were significantly higher than those of unmarried patients (t=27.096, 4.885, P<0.05 or P<0.01). There were statistically significant differences in the scores of physical function, mental health, social relations, general health status of patients with different causes of injury (F=3.000, 5.438, 4.005, 9.125, P<0.05 or P<0.01). There were statistically significant differences in the scores of mental health and general health status of patients with different sources of expenses (F=10.456, 3.368, P<0.05 or P<0.01). The total scores of quality of life of patients with different gender and causes of injury were similar (t=0.407, F=1.145, P>0.05); there were statistically significant differences in the total scores of quality of life of patients of different age groups, with different education levels, occupations, sources of expenses, and marital status (F=2.947, 17.064, 9.324, 4.101, t=7.225, P<0.05 or P<0.01). Multivariate linear regression analysis showed that age, education level, occupation, marital status, and source of expenses were the factors influencing the quality of life of patients at discharge (t=-2.437, 8.037, -2.994, 5.016, 3.519, P<0.05 or P<0.01). Conclusions: The quality of life of patients with deep partial-thickness and above burns on head and face is at a low level at discharge. The influencing factors include age, education level, occupation, marital status, and source of expenses. Nurses should screen the relevant items when the patient is hospitalized. Emphasis should be laid on young, with undergraduate and above education, unmarried, self-funded patients, and those engaged in occupations with high facial requirements, to minimize the negative mood of patients, encourage them to face life, choose the right career, and improve their quality of life.

[Effects of skin γδ T lymphocytes on wound healing of mice through regulating proliferation and differentiation of mice epidermal cells]

Objective: To explore effects of dendritic epidermal T cells (DETCs) and Vγ4 T lymphocytes on proliferation and differentiation of mice epidermal cells and the effects in wound healing of mice. Methods: (1) Six C57BL/6 male mice aged 8 weeks were collected and divided into control group and wound group according to random number table (the same grouping method below), with 3 mice in each group. A 4 cm long straight excision with full-thickness skin defect was cut on back of each mouse in wound group, while mice in control group received no treatment. On post injury day (PID) 3, mice in 2 groups were sacrificed, and skin within 5 mm from the wound margin on back of mice in wound group and normal skin on corresponding part of mice in control group were collected to make single cell suspensions. The percentage of Vγ4 T lymphocyte expressing interleukin-17A (IL-17A) and percentage of DETCs expressing insulin-like growth factor Ⅰ (IGF-Ⅰ) were detected by flow cytometer. (2) Ten C57BL/6 male mice aged 8 weeks were collected and divided into control group and Vγ4 T lymphocyte depletion group with 5 mice in each group. Mice in Vγ4 T lymphocyte depletion group were injected with 200 g Vγ4 T lymphocyte monoclonal neutralizing antibody of Armenian hamster anti-mouse intraperitoneally, and mice in control group were injected with the same amount of Armenian hamster Ig intraperitoneally. One hole with full-thickness skin defect was made on each side of spine of back of each mice. The wound healing was observed on PID 1-8, and percentage of remaining wound area was calculated. (3) Six C57BL/6 male mice aged 8 weeks were grouped and treated in the same way as in experiment (2), with 3 mice in each group. On PID 3, expressions of IL-17A and IGF-Ⅰ in epidermis on margin of wound were detected with Western blotting. (4) Thirty C57BL/6 male mice aged 3 days were sacrificed, and epidermal cells were extracted. The keratin 14 positive cell rate was examined by flow cytometer (the same detecting method below). (5) Another batch of mouse epidermal cells were collected and divided into control group, IGF-Ⅰ group, and IL-17A group, with 3 wells in each group (the same well number below). Cells in IGF-Ⅰ group and IL-17A group were added with 1 mL recombinant mouse IGF-Ⅰ and IL-17A with final mass concentration of 100 ng/mL respectively, while cells in control group were added with the same amount of sterile phosphate buffered saline (PBS). On post culture day (PCD) 5, keratin 14 negative cell rate was examined. Another batch of mouse epidermal cells were collected, grouped, and treated in the same way as aforementioned experiment, and keratin 10 positive cell rate was examined on PCD 10. (6) Another batch of mouse epidermal cells were collected and added with 4 mmol/L 5(6)-carboxyfluorescein diacetate N-succinimidyl ester (CFSE) solution, and divided into control 0 d group, control 7 d group, IGF-Ⅰ group, and IL-17A group. Cells in IGF-Ⅰ group and IL-17A group were treated in the same way as the corresponding groups in experiment (5), and cells in control 0 d group and control 7 d group were treated in the same way as the control group in experiment (5). The CFSE fluorescence peaks were examined on PCD 0 of control 0 d group and PCD 7 of the other 3 groups. (7) Another batch of mouse epidermal cells were collected and divided into control group and IGF-Ⅰ group. Cells in IGF-Ⅰ group were added with 1 mL recombinant mouse IGF-Ⅰ with final mass concentration of 100 ng/mL, and cells in control group were added with the same amount of sterile PBS. On PCD 5, cells were underwent keratin 14 staining and CFSE staining as aforementioned, and keratin 14 negative cell rate of CFSE positive cells was examined. Another batch of mouse epidermal cells were collected and divided into control group and IL-17A group. Cells in IL-17A group were added with 1 mL recombinant mouse IL-17A with final mass concentration of 100 ng/mL, and cells in control group were added with the same amount of sterile PBS. On PCD 5, keratin 14 negative cell rate of CFSE positive cells was examined. Data were processed with one-way analysis of variance and t test. Results: (1) On PID 3, percentage of DETC expressing IGF-Ⅰ in normal epidermis of control group was (9.9±0.8)%, significantly lower than (19.0±0.6)% of epidermis around margin of wound group (t=8.70, P<0.01); percentage of Vγ4 T lymphocyte expressing IL-17A in normal epidermis of control group was (0.123±0.024)%, significantly lower than (8.967±0.406)% of epidermis around margin of wound group (t=21.77, P<0.01). (2) On PID 1-4, there was obvious inflammatory reaction around wounds of mice in control group, and on PID 5-8, the wound area was still large. On PID 1-4, there was slight inflammatory reaction around wounds of mice in Vγ4 T lymphocyte depletion group, and on PID 5-8, the wound area was significantly reduced. On PID 3-7, percentages of residual wound area in Vγ4 T lymphocyte depletion group were significantly lower than those in control group (t=5.92, 5.74, 7.17, 5.38, 5.57, P<0.01), while percentages of residual wound area in two groups on PID 1, 2, 6 were similar (t=1.46, 3.17, 3.10, P>0.05). (3) On PID 3, compared with those in control group, expression of IL-17A and IGF-Ⅰ in epidermis around wound margin of mice in Vγ4 T lymphocyte depletion group was markedly decreased and increased respectively (t=8.47, 19.24, P<0.01). (4) The keratin 14 positive cell rate of mouse epidermal cells was 94.7%. (5) On PCD 5, the keratin 14 negative cell rate of mice in control group was markedly higher than that of IGF-Ⅰ group, while significantly lower than that of IL-17A group (t=7.25, 5.64, P<0.01). On PCD 10, the keratin 10 positive cell rate of mice in control group was significantly higher than that of IGF-Ⅰ group, while significantly lower than that of IL-17A group (t=3.99, 10.82, P<0.05 or P<0.01). (6) Compared with that of control 0 d group, CFSE fluorescence peaks of mouse epidermal cells in control 7 d group, IGF-Ⅰ group, and IL-17A group on PCD 7 shifted to the left. Compared with that of control 7 d group, CFSE fluorescence peaks of mouse epidermal cells in IGF-Ⅰ group and IL-17A group on PCD 7 shifted to the left. (7) On PCD 5, keratin 14 negative cell rate of CFSE positive cells of mice in control group was significantly higher than that in IGF-Ⅰ group (t=9.91, P<0.01), and keratin 14 negative cell rate of CFSE positive cells of mice in control group was markedly lower than that in IL-17A group (t=6.49, P<0.01). Conclusions: In the process of wound healing, IGF-Ⅰ secreted by DETC can promote the proliferation of mouse keratin 14 positive epidermal cells and inhibit their terminal differentiation, while IL-17A secreted by Vγ4 T lymphocyte can promote the proliferation and terminal differentiation of mouse keratin 14 positive epidermal cells, thus both IGF-Ⅰ and IL-17A can affect wound healing.

[Oncolytic property of HSV-1 recombinant viruses carrying the human IL-12]

Objective: Constructed the recombinant HSV-1 deleted ICP47 and inserted human IL-12, and investigate the virus' replication ability and oncolytic property in vitro and vivo. Methods: The recombinant HSV-1 deleting ICP47 (MH1005) and then inserting human IL-12 (MH1006) were obtained with bacterial artificial chromosome technology.The replication ability and the efficiency of inhibiting tumor were detected in several nerve tumor cell lines infected with HSV-wt, MH1005 and MH1006 respectively.The murine tumor model was established by subcutaneous inoculation Neuro-2a cells on both sides of mice back respectively.A dosage of 2×10(6) PFU of HSV-wt, MH1001(recombinant HSV-1 deleted IR), MH1005, MH1006 and Mock were injected 3 times intratumorally on one side of mice back in every 3 days, the tumor volume and survival rate of the mice were measured. Results: The replication abilities of MH1005, MH1006 and HSV-wt in 293FT cells were insignificant (P>0.05); the replication abilities of recombinant HSV-1 in G422 and Neuro-2a were higher than that in SK-N-SH; and the nerve tumor cells could be inhibited significantly by recombinant HSV-1.After 15 days of treatment, on the mouse backside with injection treatment, the tumor volumes of group HSV-wt (6 267±484), MH1001 (5 730±1 071), MH1005 (4 537±538)and MH1006 (4 150±476)mm(3) were smaller than that of group Mock (6 957±722) mm(3) significantly (all P<0.01); on the mouse backside without injection treatment, the tumor volumes of group MH1005 (5 952±607) and MH1006 (5 473±661) mm(3) were smaller than those of HSV-wt (6 785±1 063), MH1001 (6 774±808) and Mock (6 957±190) mm(3) significantly (all P<0.05); after 35 days of treatment, the mice survival rates of group MH1005 (100%) and MH1006 (100%) were higher than those of MH1001 (67%), HSV-wt (50%) and Mock (33%) significantly (all P<0.05). Conclusion: MH1005 and MH1006 can infect nerve tumor cells and replicate at high level, the viruses not only kill tumor cells directly but also induce immunological rejection to tumor, and prolong the survival of mice bearing tumor.

Perilla Oil Supplementation Improves Hypertriglyceridemia and Gut Dysbiosis in Diabetic KKAy Mice

SCOPE

The aim of this study is to examine whether perilla oil supplementation improves glucolipid metabolism and modulates gut microbiota in diabetic KKAy mice.

METHODS AND RESULTS

The successfully established diabetic KKAy mice are randomized into four groups: diabetic model (DM), low-dose perilla oil (LPO), middle-dose perilla oil (MPO), and high-dose perilla oil (HPO). C57BL/6J mice are fed a chow diet as normal control (NC). At the end of 12 weeks, mice are euthanized and glucolipid indications are analyzed. Gut microbiota analysis is carried out based on the sequencing results on V4 region of 16S rRNA. Although serum glucose, insulin, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, abundance-based coverage estimator, and shannon are unchanged, serum triglyceride significantly decreases in LPO compared with DM. The histopathological changes of hepatocellular macrovesicular steatosis and adipocyte hypertrophy are ameliorated by perilla oil supplementation. Blautia is significantly decreased in LPO, MPO, and HPO, compared with DM. Nonmetric multidimensional scaling analysis shows NC and LPO are relatively coherent.

CONCLUSION

These findings indicate that dietary supplementation with perilla oil can improve hypertriglyceridemia and gut dysbiosis in diabetic KKAy mice, which can be associated with potential benefits to human health.

[The localization diagnosis of patients with adrenocorticotropic hormone-dependent Cushing's syndrome in adolescence]

Objective: To elucidate the clinical characteristics and localization diagnosis of patients with adrenocorticotropic hormone (ACTH)-dependent Cushing's syndrome (CS) in adolescence. Methods: The clinical data, laboratory examination and localization diagnosis from 35 patients aged less than 18 years old with adolescent CS who were treated at Peking Union Medical College Hospital between January 1990 and March 2012 were analyzed. Results: There were 29 cases of Cushing's disease (CD) and 6 cases of ectopic ACTH syndrome (EAS). Compared to patients with EAS, those with CD were older at diagnosis[(15.2±2.7) vs (12.8±4.4) years], and had longer disease course[(1.9±1.5) vs (0.7±0.3) years]and higher serum potassium[(3.8±0.6) vs (2.5±0.7) mmol/L], however the plasma ACTH level[(15.4±14.9) vs (42.5±22.7) pmol/L]was lower (all P<0.05). If the cut-off of the ratio of 24-hour urine free cortisol (24 h UFC) after low-dose dexamethasone suppression test (LDDST) to before LDDST was 0.65, the sensibility to diagnose CD was 70.8%, and the specificity was 100%. If the cut-off of the 24 h UFC ratio after high-dose dexamethasone suppression test (HDDST) to before HDDST was 0.54, the sensibility to diagnose CD was 91.7%, and the specificity was 100%. If the cut-off of the plasma ACTH ratio of inferior petrosal vein[bilateral inferior petrosal sinus sampling (BIPSS)]to peripheral vein was 2, only 6 CD patients (6/8) met it. Conclusion: The study suggested that HDDST was more meaningful in the localization diagnosis of patients with ACTH-dependent CS in adolescence.

Tacrolimus population pharmacokinetics according to CYP3A5 genotype and clinical factors in Chinese adult kidney transplant recipients

WHAT IS KNOWN AND OBJECTIVES

Tacrolimus is characterized by a narrow therapeutic index and a considerable inter- and intraindividual pharmacokinetic variability. The aim of our study was to develop a population pharmacokinetic model of tacrolimus in adult kidney transplant of Chinese patients, identify factors especially CYP3A5*3 genetic polymorphism that explain variability, and determine dosage regimens.

METHODS

Pharmacogenomic data obtained from 83 Chinese kidney transplant patients treated with tacrolimus were determined using polymerase chain reaction-restriction fragment length polymorphism analysis. Trough blood concentration data were collected from all of the patients during the 12 months of post-transplantation days and were analysed using the nonlinear mixed-effects modelling program. After building the final model, 1000 bootstraps were performed to validate the final model.

RESULTS AND DISCUSSION

A one-compartment model with first-order absorption and elimination adequately described the pharmacokinetics of tacrolimus. In this study, we observed that POD, HCT and CYP3A5*3 genotype were determinant factors in CL/F and POD related with V/F of tacrolimus significantly. The final model with the clearance covariates was presented as: Cl/F=THETA(1)*EXP(THETA(4)*(83/POD))*(39.1/HCT)**THETA(5)*EXP(THETA(6)*CYP3A5), and the final model with the volume covariates was presented as: Vd/F=THETA(2)*POD**THETA(3). The Ka was fixed to 4.5 h^-1 .

WHAT IS NEW AND CONCLUSION

The HCT, CYP3A5*3 genetic polymorphism and POD contributed to the interindividual variability of oral tacrolimus in Chinese adult renal transplant patients.

[Treatment effects analysis of preoperative long-acting somatostatin analogs combined trans-sphenoidal endoscopic surgery for patients with growth hormone secreting pituitary macroadenomas]

Objective: To evaluate the treatment effects of preoperative long-acting somatostatin analogue (SSA) combined trans-sphenoidal endoscopic surgery for patients with growth hormone (GH)-secreting pituitary macroadenomas. Methods: Retrospective analysis was carried out on 20 patients with GH-secreting pituitary macroadenomas who were treated with preoperative SSA and trans-sphenoidal endoscopic surgery in our apartment from January 2010 to January 2016. We also selected 20 patients with only trans-sphenoidal endoscopic surgery treatment and 20 patients with preoperative SSA and non-trans-sphenoidal endoscopic surgery treatment. The changes of tumor imaging, endocrine and blood pressure before and after treatment were analysed. Results: The Gross total resection (GTR) rate of invasive GH-secreting pituitary macroadenomas of preoperative SSA combined trans-sphenoidal endoscopic surgery group (8/13) were higher than that if only trans-sphenoidal endoscopic surgery group (4/16) and preoperative SSA combined non endoscopic surgery group (1/8) (P<0.05). Meanwhile, preoperative SSA combined trans-sphenoidal endoscopic surgery group had significantly improved the GH levels, blood glucose, lipid metabolism and blood pressure levels (P<0.05). Conclusion: The trans-sphenoidal endoscopic surgery on patients with GH-secreting pituitary macroadenomas has a significant improvement on GH levels, blood glucose, lipid metabolism and blood pressure levels. Through the treatment of preoperative long-acting SSA, the gross total resection rate is higher than other two groups.

[The value and comparison of plasma adrenocorticotropic hormone and urinary free cortisol in predicting long-term outcome after operation of Cushing's disease]

Objective: To study and the value of morning plasma adrenocorticotropic hormone (ACTH) and urinary free cortisol (24 h UFC) within 3 days after operation in patients with Cushing's disease in predicting the long-term outcome. Methods: The clinical data of 140 patients with Cushing's disease who were treated in Department of Neurosurgery of PUMCH from 2012 to 2014 were analyzed retrospectively.The univariate analysis, multivariate Logistic analysis, ROC curve analysis and other statistical methods were used to study the predicting value of morning plasma ACTH and 24 h UFC in 3 days post operation. Results: Univariate analysis showed that in the two groups of the early remission and no remission, there was significant statistical difference between the preoperative ACTH, preoperative 24 h UFC, postoperative ACTH and postoperative 24 h UFC (P<0.05, <0.01, <0.01). Logistic analysis showed that ACTH and 24 h UFC after operation of two groups had significant difference (P<0.01, <0.05). ROC curve analysis showed that postoperative cutoff values of ACTH and 24 h UFC were 4.11 pmol/L (18.7 pg/ml) and 281.42 nmol (102 μg)/24 h. ROC analysis was performed to evaluate the predicting performance of postoperative ACTH, resulting in an area under the curve (AUC) of 0.917 (95%CI: 0.858-0.957, P<0.01). In comparison, 24 h UFC had an AUC of 0.814 (95%CI: 0.739-0.875, P<0.01). The predicting value of ACTH is significantly better than that of 24 h UFC (P=0.005). Conclusion: Early morning 24 h UFC and ACTH within 3 days after operation both showed considerable accuracy in predicting the long-term outcome of Cushing's disease, and the significance of ACTH was even greater than that of 24 h UFC.

An investigation report about the lack of VB1

From August 1 to September 26, 2012, 30 workers who had the symptom of edema in both lower limbs were reported in Yancheng, Four severe edemas in both lower limbs workers were sent to the hospital, and one person of the workers died. The epidemiology investigation and laboratory testing (in the urine loading tests, the concentration of VB1 of the workers living in the factory for more than half of the year decreased far below the normal values) were conducted to explore the cause. Furthermore, after one-week intramuscular injection of thiamine treatment, the clinical symptoms of the workers had been improved greatly. Finally, the lake of the thiamine (VB1) was considered to be the reason of this incident.

[Use early morning serum cortisollevel to evaluate the effect of Cushing's disease after transsphenoidal surgery]

OBJECTIVE

To predict the therapeutic effect of Cushing's disease after transsphenoidal surgery by using morning serum cortisol level.

METHODS

The clinical data of 275 cases that had transsphenoidal surgery in Peking Union Medical College Hospital from 2010 to 2014 were analyzed retrospectively.Early morning serum cortisol level less than 140 nmol/L 3 days postoperation was usedto predict endocrinological remission. And long-term efficacy was evaluated by follow-up.

RESULTS

Of the 275 patients, there were 49 males and 226 females; average age was 36.5 years old.Remission wasconfirmed in 201 cases, the remission rate was 73.1%, and 8 cases recurrent duringfollow-up.There were 17 macroadenomas, theremission rate was 47.1%; 258 microadenomas and MRI negative adenomas, the remission rate was 74.8%.And 43 recurrent cases had reoperations; the remission rate was 46.5%.

CONCLUSION

Early morningserum cortisol 3 days post operation can evaluate the effectof transsphenoidal surgery, but even if the level of cortisol is less than 140 nmol/L, there is still tumor recurrence.Patients should be follow-up for a lifetime.

[Comparison of efficacy between the serum cortisol and 24 hour urine free cortisol in combined dexamethasone suppression test in the diagnosis of Cushing syndrome]

OBJECTIVE

To compare the sensitivity and specificity between the 24 hour urine free cortisol (24 h UFC) and serum cortisol in dexamethasone suppression test (DST) in the diagnosis of Cushing syndrome (CS).

METHODS

Combined low dose DST (LDDST) and high dose DST (HDDST) were carried out in 67 cases of CS with surgically confirmed cases in recent 3 years(from January 2011 to November 2015). The serum cortisol and 24 h UFC were collected simultaneously for each subject and the sensitivity and specificity of serum cortisol and 24 h UFC were compared.

RESULTS

There were Cushing disease (CD) group (n=53), ectopic adrenocorticotropic hormone (ACTH) syndrome group (n=7) and ACTH-independent Cushing syndrome group (n=7) according to the etiology of hypercorticordism.There were no significant differences among 3 groups in gender and age.The sensitivity of serum cortisol of different cut off points(50, 110, 140 nmol/L and 50% of control)after LDDST was 97.01%, 86.57%, 83.58% and 70.15% respectively.Meanwhile, the sensitivity of cutoff point of 24 h UFC <32 nmol in combined LDDST was 92.54% in the diagnosis of Cushing syndrome.There was no significant differences in two groups between serum cortisol <110 nmol/L and 24 h UFC <32 nmol.However, the sensitivity of serum cortisol <50 nmol/L was significantly higher than 24 h UFC<32 nmol (P<0.05). Furthermore, in combined HDDST, if the suppression rate was ≥50%, the sensitivity of serum cortisol and 24 h UFC in differentiating the etiology of Cushing disease was 60.38% and 90.57%, and the specificity was 91.43% and 96.00% respectively.There were significant differences between serum cortisol and 24 h UFC in both of sensitivity and specificity (both P<0.05). In addition, if the suppression rate of 24 h UFC in HDDST was adjusted to 60.85% according to receiver operating characteristic (ROC) curve, it could have the best levels of sensitivity (92.6%) with the specificity of 85.7%. If the suppression rate of serum cortisol was adjusted to 61.53% in HDDST according to ROC curve, it could have the best sensitivity (64.8%) with the specificity of 78.6% accordingly.

CONCLUSION

In combined LDDST, the serum cortisol <50 nmol/L had a higher sensitivity than the 24 h UFC<32 nmol when they were used as the criteria in determining the diagnosis of CS.In HDDST, the sensitivity and specificity of suppression rate of 24 h UFC ≥50% were better than serum cortisol to differentiate the etiology of CS.

[Determination of total Bromine in urine by inductively coupled plasma mass spectrometry (ICP-MS)]

OBJECTIVE

To establish a method to determine total bromine in urine.

METHOD

Diluted urine samples were directly introduced into ICP-MS then quantized by standard curve.

RESULT

Total bromine in urine was linear within 1.0~50 mg/L with r > 0.999, When spiked at a concentration of 0.020 mg/L, 0.050 mg/L, 0.150 mg/L, the recovery was 95%~98%, intra-assay precision was 1.4% 3.2%, inter-assay precision was 3.4% to 5.0%. Urine could store in -20 °C refrigerator 3 months without any bromine loss.

CONCLUSION

Using ICP-MS to determine the urinary total bromine, the method is fast, accurate, wide linear range of features, could meet with the requirement of Part 5 of occupational health standards guide: Method determination of chemical substances in biological materials (GBZ/T 210.5-2008), a strong competitive advantage in a wide range of survey, suitable for promotion.

An efficient and rapid thin-layer chromatography method for the identification of 32 dye substances in hair dye products

OBJECTIVE

The use of dye substances in hair dye products has led to controversial public and scientific discussions about their impact on human health. This study aimed to explore a rapid method for identification of dye substances in hair dye products.

METHODS

Thin layer chromatography (TLC) method was conducted in this study. We developed basic data of 32 dye substances by 4 developing solvents and 2 indicator sprays. The dye substances were identified by comparing the Rf values and colors between samples and reference substances.

RESULTS

Thirty samples were identified by the established method. 22 hair dye substances were detected in 16 formula known samples, 15 hair dye substances were detected in 14 formula unknown samples. Four laboratories participated in the validation and the results showed good interlaboratory reproducibility.

CONCLUSION

The developed TLC method is simple, rapid, reliable and can be finely used for identification of dye substances in hair dye products.

Chiral Ligands Derived from Abrine 8. An Experimental and Theoretical Study of Free Ligand Conformational Preferences and the Addition of Diethylzinc to Benzaldehyde

Three structurally similar series of 1,2,3,4-tetrahydro-beta-carboline ligands, 4a-d, 6a-d and 7a-d, and two series of chiral oxazolidines, 8a-d and 9a-g, were synthesized and used as chiral catalysts in the addition of diethylzinc to benzaldehyde. The enantioselectivities of the resulting 1-phenyl-1-propanol were obtained in each case, and these ee values were, in most cases, related to the conformational populations of the free ligand as expressed by the calculated differences in the energies of the ligand conformations formed by inversion at nitrogen. This suggested the possible existence of a linear free energy relationship. The effect on enantioselectivity of the carbon chain length of the R group located (1) on the C-3 substituent of 4a-d, 6a-d, and 7a-d or (2) at C-5 in 8a-d and 9a-g was studied in detail. On the basis of the correlations observed and the ligands' structural characterization, a structure was proposed for the transition state during ethyl group transfer when using ligands 8a-d. Furthermore, the change in enantioselectivity was successfully predicted when diastereomeric ligands 11 and 12 were compared in this chiral addition.

Regulation of transforming growth factor-beta signaling

Members of transforming growth factor beta (TGF-beta) family are potent regulators of multiple cellular functions, including cell proliferation, differentiation, migration, organization, and death. Yet the signaling pathways underpinning a wide array of biological activities of TGF-beta appear to be deceptively simple. At every step from TGF-beta secretion to activation of its target genes, the activity of TGF-beta is regulated tightly, both positively and negatively. Biologically active TGF-beta is cleaved from a precursor protein (latent form) and multiple process factors control the levels of active TGF-beta. The efficient secretion, correct folding and deposition to the extracellular matrices require the cosecretion of latent TGF-beta binding proteins (LTBPs). Once activated, TGF-beta ligand signals through a heteromeric receptor complex of two distinct type I and type II serine/threonine kinase receptors TbetaRI and TbetaRII. Many factors appear to influence the formation of the active ligand-receptor complex. The relative orientation of TbetaRI and TbetaRII in the ligand-receptor complex is critical for activation: through TbetaRI, the activated ligand-receptor complex directly binds and phosphorylates downstream intracellular substrates, called Smads. Inhibitory Smads, Smad6 and 7, can antagonize this process. The phosphorylation of Smads leads to the formation of complexes which translocate to the nucleus. Other signaling systems can modulate the activity of the Smads: e.g., ras activity can prevent Smad complexes from entering the nucleus and specific ubiquitin ligases can target Smad for degradation. In the nucleus, the Smad complexes associate with other transcription activators or suppressors to regulate gene expression, either positively or negatively. The combined effects of the positive and/or negative TGF-beta controlled gene expression together with the endogenous protein set of the target cell are responsible for the multiplicity of biological functions.

Room-temperature spin injection from Fe into GaAs

Injection of spin polarized electrons from a metal into a semiconductor is demonstrated for a GaAs/(In,Ga)As light emitting diode covered with Fe. The circular polarization degree of the observed electroluminescence reveals a spin injection efficiency of 2%. The underlying injection mechanism is explained in terms of a tunneling process.

Platelet-derived growth factor requires epidermal growth factor receptor to activate p21-activated kinase family kinases

The platelet-derived growth factor (PDGF) receptor (PDGFR) transactivates the epidermal growth factor (EGF) receptor (ErbB1) to stimulate the cell migration of fibroblasts through an unknown mechanism (Li, J., Kim, Y. N. & Bertics, P. (2000) J. Biol. Chem. 275, 2951-2958). In this paper we provide evidence that the transactivation of the EGF receptor (EGFR) by PDGFR is essential for PDGF to activate p21-activated kinase (PAK) family kinases. Fetal calf serum (10%) transiently stimulates the PAK activity in NIH 3T3 fibroblasts. The activation of PAK was completely inhibited by either PDGFR-specific inhibitor (AG1295) or EGFR-specific inhibitor (AG1478), suggesting that serum requires either the PDGF- or EGF-dependent pathway or the combination of both to activate PAK. PDGF-induced activation of PAK is completely inhibited by either AG1295 or AG1478, indicating that PDGF requires both PDGFR and EGFR for PAK activation. In support of this notion, a mouse embryo fibroblast cell line derived from the EGFR -/- mouse (from Dr. Erwin Wagner) doesn't activate PAK in response to PDGF. Expression of human EGFR in this cell line restores the ability of the PDGF to induce PAK activation. Our results indicate that PDGF activates PAK through transactivation of ErbB1.

Microencapsulation of ascorbic acid: effect of process variables on product characteristics

This study deals with a comparative investigation of the characteristics of ascorbic acid microcapsules prepared by different methods, such as thermal phase separation, melt dispersion, solvent evaporation and spray drying. Scanning electron microscopy (SEM), release tests and size distribution were used for the evaluation of product characteristics. The results show that microencapsulated ascorbic acid could prevent the ascorbic acid colour change, retard its core release rate, and generally mask its acid taste. In the thermal phase separation, molecular weight (Mw) of ethyl cellulose (EC) and the addition of polyisobutylene (PIB) significantly influenced the aggregation and release rate of microcapsules. In the melt dispersion method, spherical particles were prepared by using carnauba. The ascorbic acid release rate was found to be slower in the case of carnauba-encapsulated ascorbic acid than that made by EC using other methods. In the solvent evaporation method, a higher Mw of EC and the addition of plastizer were also found to be important for good encapsulation. In the spray drying method, loss of ascorbic acid was found to be minimum during microencapsulation. Starch and beta-cyclodextrin encapsulated ascorbic acid delayed the degradation of ascorbic acid during storage at 38 degrees C and relative humidity 84.0%.

Smad7 differentially regulates transforming growth factor beta-mediated signaling pathways

Smad7 has been identified as a negative regulator of transforming growth factor beta (TGF-beta) signaling by interfering with the phosphorylation of other Smad proteins by TGF-beta receptor type I (TbetaRI). We established a mink lung epithelial (Mv1Lu) cell line where ectopic expression of Smad7 is tightly controlled by doxycycline using an improved Tet-on system. Once induced by doxycycline, the recombinant Smad7 was localized predominantly in the perinuclear region and in the cytoplasm. However, the type of culture surface alters the subcellular localization of Smad7: on plastic or on fibronectin-coated glass, Smad7 was localized in the cytoplasm; but when the cells were cultured on glass, nuclear localization was observed. TGF-beta stimulation did not alter substantially the cellular distribution of Smad7. Importantly, the expression of recombinant Smad7 differentially inhibited TGF-beta signaling pathways. Consistent with previous studies, Smad7 inhibited TGF-beta-stimulated induction of type 1 plasminogen activator inhibitor as measured by p3TP-Lux reporter. However, expression of Smad7 had little effect on TGF-beta-induced growth inhibition.

Extracellular domain of the transforming growth factor-beta receptor negatively regulates ligand-independent receptor activation

We have previously proposed that transforming growth factor (TGF)-beta receptor activation occurs via a relative rotation between the receptors. This model suggests that in the absence of the ligand the receptor extracellular domain negatively regulates the activation of the receptor complex. To investigate this proposition, four TGF-beta type I and II receptor extracellular/transmembrane-cytoplasmic and extracellular-transmembrane/cytoplasmic chimeras, TbetaRII-I-I and TbetaRI-II-II as well as TbetaRII-II-I and TbetaRI-I-II, and two extracellular domain truncated receptors TbetaRI-STC and TbetaRII-STC were generated. In either mutant mink lung R1B (lacking functional type I receptor) or DR26 (where the type II receptor is nonfunctional) cells, coexpression of two chimeric receptors, which are complementary in extracellular and cytoplasmic domains, transduced TGF-beta induced signaling, as measured by the transcriptional activation of a p3TP-Lux reporter gene. Coexpression of this type of chimeric receptor with a wild-type receptor containing the opposite cytoplasmic domain exhibited a varied level of constitutive activity depending on the particular combination of the extracellular domains. In general, the type I-type I extracellular domain combination gave higher constitutive activity than the type I-type II or type II-type II combinations. Furthermore, coexpression of the extracellular domain truncated receptor with any receptor containing the opposite cytoplasmic domain always resulted in ligand independent receptor signaling. Immunoprecipitation studies showed that the formation of the receptor complexes paralleled the ligand independent activation of p3TP-Lux. Our results support the conclusion that the TGF-beta receptor extracellular domain plays a negative regulatory role in receptor activation in the absence of ligand.

A pivotal role for the transmembrane domain in transforming growth factor-beta receptor activation

Transforming growth factor-beta (TGF-beta) delivers diverse growth and differentiation signals by binding two distantly related transmembrane serine/threonine kinase receptors: the type I receptor (TbetaRI) and the type II receptor (TbetaRII). In an attempt to establish the role of the transmembrane domain in receptor signaling, two chimeric TGF-beta receptors, TbetaRI-II-I and TbetaRII-I-II, containing the opposite transmembrane domain were generated. When transfected into a mutant mink lung epithelial cell line R1B, which lacks functional TbetaRI, TbetaRI-II-I restored TGF-beta1-induced transcriptional activation of a TGF-beta reporter p3TP-Lux to approximately 25% of the levels restored by wild-type TbetaRI. In the mutant mink lung epithelial cell line DR26, which contains a truncated, nonfunctional TbetaRII, wild-type receptor TbetaRII restored the TGF-beta responsiveness, while the TbetaRII-I-II cDNA was inactive. When both TbetaRI and TbetaRII were transfected into R1B, DR26, or Mv1Lu cells, a low level of constitutive p3TP-Lux activity was observed. However, cotransfection of both transmembrane chimeric receptors, TbetaRI-II-I and TbetaRII-I-II, or the wild-type TbetaRI with the transmembrane chimeric TbetaRII-I-II resulted in high levels of ligand-independent receptor activation. These results suggest that the transmembrane domains of both TGF-beta receptors are essential and play a pivotal role in receptor activation. To investigate the role of the transmembrane domain further, four type II transmembrane mutants were generated: TbetaRIIDelta-1, TbetaRIIDelta-2, TbetaRIIDelta-3, and TbetaRIIDelta-4, which have one, two, three, or four amino acids deleted at the N terminus of the transmembrane domain, respectively. Interestingly, co-expression of TbetaRIIDelta-1 with the wild-type TbetaRI in DR26 cells resulted in high levels of constitutive activation, while only low levels of the activation were observed when TbetaRIIDelta-2, TbetaRIIDelta-3, or TbetaRIIDelta-4 were co-expressed with the wild-type TbetaRI. However, TbetaRIIDelta-1 restored very little the TGF-beta responsiveness in DR26cells. Expression of TbetaRIIDelta-2, TbetaRIIDelta-3, and TbetaRIIDelta-4 resulted in a progressive increase in TGF-beta responsiveness, with TbetaRIIDelta-4 reaching the level of activity of the wild-type TbetaRII. Furthermore, like TbetaRII-I-II, co-expression of TbetaRIIDelta-1 with TbetaRI-II-I also resulted in high levels of constitutive activation. These results are consistent with an important role for the transmembrane region of the receptors. We further propose a model of receptor activation in which receptor activation occurs via relative orientational rotation.

Cloning of an Apobec-1-binding protein that also interacts with apolipoprotein B mRNA and evidence for its involvement in RNA editing

Apolipoprotein (apo)B mRNA editing is mediated by a multiprotein editosome complex. Apobec-1 is the catalytic component of this complex, but other proteins involved in editing have not been identified. We used the yeast two-hybrid system to identify an apobec-1-interacting protein, ABBP-1. ABBP-1 contains 331 amino acid residues and is identical to a previously reported human type A/B hnRNP except for a 47-residue insertion at its C-terminal region. It contains typical RNP motifs at its N-terminal half and glycine-rich motifs in the C-terminal region. Northern blot analysis indicates that ABBP-1 mRNA is distributed in multiple human tissues. By deletion analysis, we mapped the apobec-1-binding region to the glycine-rich domain. ABBP-1 also binds to apoB mRNA transcripts around the editing site and can be UV-cross-linked to them in vitro. Immnodepletion of ABBP-1 from an active apoB mRNA editing tissue extract inhibits its editing activity. Down-regulation of ABBP-1 in an apobec-1-expressing HepG2 cell line by transfection with an antisense ABBP-1 cDNA construct leads to inhibition of endogenous apoB mRNA editing. We conclude that ABBP-1 is an apobec-1-interacting protein that may play an important role in apoB mRNA editing.