Impact of different anastomosis methods on post-recurrence after intestinal resection for Crohn's disease: A meta-analysis

BACKGROUND

Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract, often requiring intestinal resection as a common treatment. However, recurrence after surgery is common. The anastomotic configuration after bowel resection appears to be associated with the recurrence of CD. Previous studies have suggested that the Kono-S anastomosis may help to reduce the recurrence rate. However, the results remain controversial. Therefore, evidence-based evidence is needed to prove the advantages of Kono-S anastomosis.

AIM

To measure the influence of anastomosis techniques on the long-term relapse rate of CD by conducting a meta-analysis.

METHODS

PubMed, Scopus, and Cochrane Library were searched until October 8, 2023. Patients who underwent intestinal resection due to CD were included. The intervention measures included Kono-S anastomosis, whereas the control group received traditional anastomosis such as end-to-end, end-to-side, and side-to-side anastomosis. Only randomized clinical trials and observational studies were included. The primary outcome measures were hospital stay post-surgery, overall postoperative complication incidence, the proportion of Clavien-Dindo grade IIIa or higher, overall postoperative recurrence rate, and Rutgeerts score.

RESULTS

From 2011 to 2023, six articles met the inclusion and exclusion criteria. The results indicated that Kono-S anastomosis can reduce the hospital stay post-surgery of patients with CD [MD = -0.26, 95%CI: -0.42 to -0.10, P = 0.002] than other traditional anastomosis methods. Compared to other traditional anastomosis methods, Kono-S anastomosis can significantly reduce the total recurrence rate [MD = 0.40, 95%CI: 0.17 to 0.98, P = 0.05] and postoperative Rutgeerts score [MD = -0.81, 95%CI: -0.96 to -0.66, P < 0.001] in patients with CD. However, there is no significant disparity in the overall occurrence of postoperative complications and the proportion of Clavien-Dindo ≥ IIIa.

CONCLUSION

Kono-S anastomosis has the potential to expedite the recuperation of CD and diminish relapse hazards; however, additional larger trials are necessary to authenticate its effectiveness.

Development of Cost-Effective Fatty Liver Disease Prediction Models in a Chinese Population: Statistical and Machine Learning Approaches

BACKGROUND

The increasing prevalence of nonalcoholic fatty liver disease (NAFLD) in China presents a significant public health concern. Traditional ultrasound, commonly used for fatty liver screening, often lacks the ability to accurately quantify steatosis, leading to insufficient follow-up for patients with moderate-to-severe steatosis. Transient elastography (TE) provides a more quantitative diagnosis of steatosis and fibrosis, closely aligning with biopsy results. Moreover, machine learning (ML) technology holds promise for developing more precise diagnostic models for NAFLD using a variety of laboratory indicators.

OBJECTIVE

This study aims to develop a novel ML-based diagnostic model leveraging TE results for staging hepatic steatosis. The objective was to streamline the model's input features, creating a cost-effective and user-friendly tool to distinguish patients with NAFLD requiring follow-up. This innovative approach merges TE and ML to enhance diagnostic accuracy and efficiency in NAFLD assessment.

METHODS

The study involved a comprehensive analysis of health examination records from Suzhou Municipal Hospital, spanning from March to May 2023. Patient data and questionnaire responses were meticulously inputted into Microsoft Excel 2019, followed by thorough data cleaning and model development using Python 3.7, with libraries scikit-learn and numpy to ensure data accuracy. A cohort comprising 978 residents with complete medical records and TE results was included for analysis. Various classification models, including logistic regression (LR), k-nearest neighbor (KNN), support vector machine (SVM), random forest (RF), light gradient boosting machine (LightGBM), and extreme gradient boosting (XGBoost), were constructed and evaluated based on the area under the receiver operating characteristic curve (AUROC).

RESULTS

Among the 916 patients included in the study, 273 were diagnosed with moderate-to-severe NAFLD. The concordance rate between traditional ultrasound and TE for detecting moderate-to-severe NAFLD was 84.6% (231/273). The AUROC values for the RF, LightGBM, XGBoost, SVM, KNN, and LR models were 0.91, 0.86, 0.83, 0.88, 0.77, and 0.81, respectively. These models achieved accuracy rates of 84%, 81%, 78%, 81%, 76%, and 77%, respectively. Notably, the RF model exhibited the best performance. A simplified RF model was developed with an AUROC of 0.88, featuring 62% sensitivity and 90% specificity. This simplified model used 6 key features: waist circumference, BMI, fasting plasma glucose, uric acid, total bilirubin, and high-sensitivity C-reactive protein. This approach offers a cost-effective and user-friendly tool while streamlining feature acquisition for training purposes.

CONCLUSIONS

The study introduces a groundbreaking, cost-effective ML algorithm that leverages health examination data for identifying moderate-to-severe NAFLD. This model has the potential to significantly impact public health by enabling targeted investigations and interventions for NAFLD. By integrating TE and ML technologies, the study showcases innovative approaches to advancing NAFLD diagnostics.

[Research on the framework of biosafety standards for pathogenic microbial laboratories]

Developing and implementing biosafety standards for pathogenic microbiology laboratories is essential to achieving scientific, efficient, and standardized management and operation. This article analyzes the current standardization construction in biosafety in pathogenic microbiology laboratories domestically and internationally. It proposes a framework for the biosafety standard system of pathogenic microbiology laboratories, which mainly includes four parts: basic standards, management standards, technical standards, and industry applications. It provides a reference for the standardization work of pathogenic microbiology laboratories and helps to standardize the biosafety industry in China.

Factors associated with sleep disorders among adolescent students in rural areas of China

Background

This study aimed to determine sleep patterns and the prevalence and association factors of sleep disorders in a regionally representative sample in Mo Jiang, China.

Methods

A total of 2,346 (participation rate 93.5%) Grade 7 students (aged 13-14 years) from 10 middle schools, including 1,213 (51.7%) boys and 1,133 (48.3%) girls, participated in the study. All the participants were invited to complete questionnaires that acquired information on sleep patterns, academic performance, academic stress, and sociodemographic factors. Sleep disorders were assessed using the Chinese version of the Children's Sleep Habits Questionnaire. Logistic regression models were used to investigate factors associated with sleep disorders.

Results

The prevalence of sleep disorders among rural adolescents was 76.4%, which is higher than that among urban adolescents. Compared with previous findings in urban areas, our results indicate that sleep loss is much more severe in rural adolescents. Sleep disorders were positively associated with factors, such as watching TV [odds ratio (OR) = 1.22, p = 0.001], academic performance (OR = 1.80, p < 0.001), and academic stress (OR = 1.38, p = 0.04). In addition, girls were more likely to suffer from sleep disorders than boys (OR = 1.36, p = 0.01).

Conclusion

Insufficient sleep and sleep disorders have become common health problems in rural Chinese adolescents.

Bullying victimization and suicide attempts among adolescents in 41 low- and middle-income countries: Roles of sleep deprivation and body mass

Background

Suicide is the fourth leading cause of death for adolescents, and globally, over 75% of completed suicides occur in low- and middle-income countries (LMICs). Bullying has been proven to be closely related to suicide attempts. However, further understanding of the mechanisms underlying the relationship between bullying and adolescents' suicide attempts is urgently needed.

Methods

We used data from the Global School-based Student Health Survey (GSHS) (2010-2017) from 41 LMICs or regions. This study was based on questions assessing bullying victimization, suicide attempts, sleep deprivation, and body mass. Chi-square tests were used to explore the correlations among the main variables. The mediating role of sleep deprivation and the moderating role of body mass index (BMI) were analyzed using PROCESS.

Results

The results showed a positive association between bullying victimization and suicide attempts. Sleep deprivation partially mediated the relationship between the frequency of being bullied and suicide attempts. In addition, sleep deprivation played a full or partial mediating role in the relationship between different types of bullying and suicide attempts. BMI moderated the relationships between the frequency of being bullied and suicide attempts, between being made fun of about one's body and sleep deprivation, and between sleep deprivation and suicide attempts.

Conclusion

Being bullied has a positive effect on suicide attempts, which is mediated by sleep deprivation and moderated by body mass. The results of this study are consistent with the stress-diathesis model of suicide, suggesting that being bullied is one of the stressors of suicide in adolescents, while sleep deprivation and body mass are susceptibility diatheses of suicide. The results are conducive to identifying adolescents at a high risk of suicide, suggesting that there is a need to pay more attention to bullied adolescents, especially their sleep quality and body mass, and design effective intervention measures to improve the current situation of adolescent suicide in LMICs.

[Clinicopathological observation of 10 cases of salivary secretory carcinoma]

Objective: To investigate the clinical and pathological features of salivary secretory carcinoma (SSC). Methods: Ten cases of SSC confirmed in the Department of Pathology,Capital Medical University School of Stomatology from January 2014 to December 2021 were retrospectively included, including 5 males and 5 females, with a median age of 46.5 years. The microscopic morphology, immunophenotype, special staining and clinical follow-up of 10 cases of salivary secretory carcinoma were observed. Ten patients were tested with S-100, vimentin, mammaglobin, Dog-1, p63 and Ki-67, 9 cases with cytokeratin (CK) 8/18, 8 with CK7, 6 with calponin, 5 with smooth muscle actin (SMA) and GCDFP15, 4 with CK5/6 and 1 with SOX10. The ETV6-NTRK3 fusion gene was detected by fluorescence in situ hybridization. Results: Seven of the 10 SSC were located in the parotid gland and 3 were located in the cheeks. Histomorphology showed solid, papillary-cystic, follicular, microcystic, and macrocystic types. In 7 cases, tumor cells were dominated by single arrangement type, while certain mixed arrangements existed in some areas. The cytoplasm of the tumor cells was rich in eosinophilic, fine granular or vacuolar shapes, and clear cytoplasm was seen in 2 cases. The nuclei were mostly oval-shaped vesicular nuclei, with nucleoli in the center. Immunohistochemistry showed CK7 (8/8) positive, CK8/18 (9/9) positive, S-100 (10/10) positive, vimentin (5/10) positive, (4/10) partially positive and (1/10) less partially positive, mammaglobin (7/10) positive, (1/10) partially positive and (2/10) some individual cells positive, Dog-1 (10/10) negative, CK5/6 (4/4) negative, p63 (7/10) negative and (3/10) partially positive, SMA (5/5) negative, calponin (6/6) negative, and Ki-67 index was 5%-20%. Secretions of 5 cases showed periodic acid-Schiff (PAS) and PAS with diastase (PAS-D) staining positive. All 10 cases showed ETV6-NTRK3 fusion positive. Six cases were successfully followed up for 32-91 months, of which 2 cases recurred after 28 and 74 months and underwent surgical resection again. All cases followed up are alive and disease-free. Conclusions: The salivary secretory carcinoma is a rare low-grade malignant tumor. In certain cases, morphology is atypical and mammaglobin is immunohistochemically positive in only individual tumor cells. Therefore, the diagnosis should be supported with morphology, immunohistochemical staining, and molecular feature preferably.

Comparison of EQ-5D-5L and EORTC QLU-C10D utilities in gastric cancer patients

BACKGROUND

To compare measurement properties of the utility scores derived from various country-specific value sets of EQ-5D-5L (5L) and EORTC QLU-C10D (10D) in gastric cancer patient.

METHODS

The study used cross-sectional data of 243 Chinese gastric cancer patients who completed both 5L and EORTC QLQ-C30. Utility score of QLU-C10D is generated from all the available QLU-C10D value sets currently; the score of 5L is derived from the corresponding 5L value sets for the countries with both the 5L and QLU-C10D value sets and the Chinese 5L value set. Convergent validity was evaluated by testing their correlations with the VAS score. Known-group validity was assessed by comparing the utility scores the patients with different severities. Their relative efficiency (RE) was also compared.

RESULTS

Correlation coefficient of 5L and QLU-C10D utility scores with VAS ranged from 0.54 to 0.59, and 0.55 to 0.63, respectively. Both the utility scores were in general able to discriminate the patients with different severities; and 5L utility score had higher RE in the majority of known-groups.

CONCLUSION

EQ-5D-5L and QLU-C10D utility scores were different and, thus, non-swappable. They possess similar convergent validity and known-group validity; while EQ-5D-5L scores may have better discriminative power.

Evaluating health-related quality of life in gastric cancer patients in Suzhou, China

BACKGROUND

Health-related quality of life (HRQOL) has become an important part of the evaluation of clinical efficacy and prognosis in gastric cancer. This study aimed to assess the HRQOL of patients with gastric cancer using the a five-level EuroQol five-dimensional questionnaire (EQ-5D-5L) and explore the factors influencing patients' perceived quality of life. For those significant factors, we can take appropriate measures to intervene to extend patient survival and improve the quality of life.

METHODS

A cross-sectional questionnaire survey was administered to 243 patients with gastric cancer in the First Affiliated Hospital of Suzhou University from December 2018 to December 2020. HRQOL was measured by the Chinese version of the EQ-5D-5L. Nonparametric test analyses and a Tobit regression model were used to identify the independent variables associated with the EQ-5D-5L utility scores.

RESULTS

In this research, the mean score was 0.810, and the median was 0.893. Approximately 25% of patients reported no problems at all in any of the five dimensions. Problems in pain and discomfort were the most frequently reported (64.2%). Nonparametric test analyses showed that patients who did not have health insurance, or who had a history of alcohol use, a family history of cancer, had received surgery only, or had an interval of less than 1 week between taking this survey and their last treatment, demonstrated lower EQ-5D-5L scores. The Tobit regression model confirmed that health insurance, family history, and treatment were significantly associated with EQ-5D-5L scores.

CONCLUSIONS

The HRQOL of gastric cancer patients can be measured by EQ-5D-5L, and the results may provide a guide for choosing an appropriate individualized treatment plan.

[Analysis of clinical characteristics and prognosis of 235 pancreatic neuroendocrine tumors underwent Sunitinib treatment]

Objective: To investigate the clinical characteristics, treatment, and prognostic factors of pancreatic neuroendocrine tumors (pNETs) patients treated with Sunitinib. Methods: The clinical data of pNETs patients from Pfizer Drug Assistance Program of Cancer Foundation of China from April 2013 to November 2017 were retrospectively analyzed. Follow-up and statistical analysis were performed. Results: A total of 235 patients were enrolled, the patients' overall survival time was between 4 and 252 months, the 3-years and 5-years survival rates were 73.8% and 60.8%, respectively. Univariate analysis showed that factors such as age, Ki-67 index and surgery were associated with the 3-years survival rates of pNETs patients (P<0.05). Multivariate analysis demonstrated that the age, Ki-67 index and surgery were independent prognostic factors for pNETs patients (P<0.05). For patients with liver metastases, univariate analysis revealed that surgery was associated with prognosis (P<0.05). The 5-years survival rate of 124 patients with extending usage of Sunitinib was 53.3%. Conclusion: PNETs are rare tumors with atypical clinical symptoms and the patients often have metastasis at the initiate diagnosis. The age, Ki-67 index and surgery are associated with the prognosis of pNETs patients.

Identification of breast cancer-related circRNAs by analysis of microarray and RNA-sequencing data: An observational study

BACKGROUND

An increasing number of studies indicate that circular RNAs (circRNAs) participate in tumorigenesis. The aim of this study was to elucidate the regulatory mechanisms of circRNAs in breast cancer based on the construction of the circRNA-related ceRNA network.

METHODS

The expression profiles of circRNAs, miRNAs, and mRNAs were obtained from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases. A ceRNA network was constructed by Cytoscape. The interactions among proteins were analyzed using the STRING database, and hub genes were extracted using the cytoHubba application. The functions of the differentially expressed mRNAs (DEmRNAs) were analyzed by the Kyoto Encyclopedia of Gene and Genomes (KEGG) and the Gene Ontology (GO) database.

RESULTS

In total, 7 differentially expressed circRNAs (DEcircRNAs), 27 differentially expressed miRNAs (DEmiRNAs), and 102 DEmRNAs were selected for the construction of the ceRNA network of breast cancer. We established a protein-protein interaction network and identified 6 hub genes. Then, a circRNA-miRNA-hub gene regulatory module was established based on 2 DEcircRNAs, 2 DEmiRNAs, and 2 DEmRNAs. GO and KEGG pathway analyses indicated the possible association of DEmRNAs with breast cancer onset and progression.

CONCLUSIONS

The circRNA hsa_circ_0000519 is likely critical in the pathogenesis of breast cancer and may serve as a future therapeutic biomarker.

[Reproductive and developmental toxicity of 2- (2H-1, 2, 3-benzotriazol-2-yl) -4-methyl-6- (2-methylpropen-2-yl) phenol in mice: an experimental study]

Objective: To investigate the reproductive and developmental toxicity of 2- (2H-1, 2, 3-benzotriazol-2-yl) -4-methyl-6- (2-methylpropen-2-yl) phenol in mice and to provide a basis for its risk assessment. Methods: The reproductive and developmental toxicity of 2- (2H-1, 2, 3-benzotriazol-2-yl) -4-methyl-6- (2-methylpropen-2-yl) phenol was tested using the screening method of chemicals with reproductive and developmental toxicity in "Chemical Testing Method" (SEPA). After five days of adaptive feeding, 120 specific pathogen-free healthy Kunming mice (male/female ratio=1:1) were orally administered 0 (control) , 146, 292, and 584 mg/kg 2- (2H-1, 2, 3-benzotriazol-2-yl) -4-methyl-6- (2-methylpropen-2-yl) phenol for two weeks. One male mouse was mated with one female mouse in a single cage. The day on which a vaginal plug was observed was defined as gestation day 0 (GD0). The exposure for female mice was sustained to four days postpartum and the exposure for male mice was sustained for two weeks after mating. The body weight, food intake, body length, tail length, and sex ratio were recorded and the reproductive index was calculated. The reproductive organs were weighed and subjected to histopathological examination. Results: The 584 mg/kg group had significantly lower body weight at weeks 5 and 6 and food intake at week 6 in male mice, uterus weight and uterus/body weight ratio in female mice, and body weight, body length, and tail length on day 0 in offspring compared with the control group (all P<0.05). The 292 mg/kg group had significantly lower testis weight of male mice and food intake of female mice at gestational week 2 than the control group (both P<0.05). The 146 mg/kg group had significantly lower food intake of female mice at gestational week 2 than the control group (P<0.05) . Conclusion: For male and female Kunming mice, the no observed adverse effect levels of 2- (2H-1, 2, 3, -benzotriazol-2-yl) -4-methyl-6- (2-methylpropen-2-yl) phenol are both 146 mg/kg.

[A cross-sectional study of seroepidemiology of viral hepatitis among Uighurs in Shufu of Xinjiang]

Objective: To explore the status of seroepidemiology on hepatitis A, B and C among students and residents aged equal or greater than 18 years in south Xinjiang, and to provide scientific evidence for prevention and control of viral hepatitis. Methods: Uyghur students in four towns and villages were selected by cluster random sampling from Feb to May, 2015, and Uyghur residents aged 18 to 69 years were selected by stratified cluster sampling from May to September, 2016. 4 507 middle and primary Uygur students and 4 833 Uyghur resides equal or greater than 18 years attended this survey. Self-designed questionnaire was used to collect the demographic information. And Elisa test was adopted to detect HAV-IgG, HBsAg, HBsAb and HCV-IgG. Chi-square test was used to calculate the difference on antibody positive rate of three types of hepatitis among the participants. Results: The overall HAV-IgG positive rate was 99.45% (9 289/9 340). The positive rates were 99.70% (4 006/4 018) in male and 99.27% (5 283/5 322) in female (χ(2)=7.95, P=0.005). The HAV-IgG positive rate among people aged 10 to 14 years was the highest (99.91%, 2 233/2 235), and the difference between the age specific HAV-IgG positive rates was statistical significant (χ(2)=38.21, P<0.001). The overall HBsAg positive rate was 4.11% (384 cases), with 4.55% (183 cases) for male and 3.78% (201 cases) for female. The HBsAg positive rate among participants 19 to 24 years old was the highest (9.46%, 21/222) and the differences between the age specific HBsAg was statistically significant (χ(2)=116.22, P<0.001). The HBsAb positive rate was 35.03% (3 272 cases), with 35.59% (1 430 cases) for male and 34.61% (1 842 cases) for female, and the HBsAb positive rate among participants aged 15 to 18 years was the highest, which was 69.12% (696/1 007). The differences between the age specific HBsAb rates appeared statistically significant (χ(2)=671.80, P<0.001). The overall HCV-IgG positive rate was 0.65%(61 cases). The HCV-IgG positive rate in female was 0.86% (46 cases) and 0.37% (15 cases) in male (χ(2)=8.51, P=0.004).The HCV-IgG positive rate among participants aged over 70 years was the highest (3.78%,9/238) , and the difference between the age specific HCV-IgG positive rates had statistic significance (χ(2)=70.30, P<0.001). The HAV-IgG positive rate in hepatitis A vaccinees (100%, 876/876) was higher than that among the non-vaccinees (99.40%, 8 413/8 464) (χ(2)=4.26, P=0.039). The HBsAb positive rate in hepatitis B vaccinees was 39.32% (1 816/4 619) which was higher than that among the non-vaccinees (30.84%, 1 456/4 721) (χ(2)=73.68, P<0.001). Conclusion: The positive rate of overall HAV-IgG was high, male and participants aged between 10 to 14 had higher probability to be infected. But the infection rates of hepatitis B and C were low, with the low vaccination rate and the poor protective effectiveness of hepatitis B.

Utilization of a Wheat660K SNP array-derived high-density genetic map for high-resolution mapping of a major QTL for kernel number

In crop plants, a high-density genetic linkage map is essential for both genetic and genomic researches. The complexity and the large size of wheat genome have hampered the acquisition of a high-resolution genetic map. In this study, we report a high-density genetic map based on an individual mapping population using the Affymetrix Wheat660K single-nucleotide polymorphism (SNP) array as a probe in hexaploid wheat. The resultant genetic map consisted of 119 566 loci spanning 4424.4 cM, and 119 001 of those loci were SNP markers. This genetic map showed good collinearity with the 90 K and 820 K consensus genetic maps and was also in accordance with the recently released wheat whole genome assembly. The high-density wheat genetic map will provide a major resource for future genetic and genomic research in wheat. Moreover, a comparative genomics analysis among gramineous plant genomes was conducted based on the high-density wheat genetic map, providing an overview of the structural relationships among theses gramineous plant genomes. A major stable quantitative trait locus (QTL) for kernel number per spike was characterized, providing a solid foundation for the future high-resolution mapping and map-based cloning of the targeted QTL.

Polygonum multiflorum causes severe hepatitis and sugar metabolism disorder: A case report and literature review

In recent years, drug-induced liver injury has become a common disease of the liver, only after viral hepatitis and fatty liver disease (alcoholic and non-alcoholic). The wide use of Chinese herbal medicine or preparation has caused an increase in the incidence of toxic side effects and adverse reactions, with the liver being easily damaged. Occasionally, severe hepatitis may occur. Here we report a case of severe hepatitis with disorder of glucose metabolism caused by taking Polygonum multiflorum.

Controllable surface morphology and properties via mist polymerization on a plasma-treated polymethyl methacrylate surface

Surface modification by grafting polymers on solid materials is an important strategy used to improve surface properties. This article reports that under appropriate conditions, very thin layers with desired morphologies may be constructed on a plasma-treated substrate by feeding a small quantity of a monomer with a mist stream carrying droplets produced from monomer solutions. We investigate the effects of process parameters that affect layer morphology, including exposure time to the mist stream, concentration of the monomer solution, and solvent selectivity. For a methyl methacrylate solution in ethanol, nanoparticles are uniformly grown with increasing monomer concentration or exposure time and finally form a porous layer at 3.65 mol L(-1) for 30 min. Decreasing solvent polarity not only affects surface morphology, but also increases hydrophobicity of the resulting surface. With 2,2,3,4,4,4-hexafluorobutyl methacrylate as the monomer, SEM and AFM micrographs indicated that mist polymerization results in numerous microspheres on the activated surface. These experimental results were interpreted by a mechanism in terms of an in situ polymerization accompanied by a phase transformation of the resulting polymer. Specifically, plasma treatment provides highly active cations and radicals to initiate very rapid polymerization, and the resulting polymers are consequently deposited from the liquid onto the surface under phase transition mechanisms.

[Concept of mesenchymal stem cells: bring more insights into functional research of MSC]

Mesenchymal stem cells have generated great interest among researchers and physicians due to their unique biological characteristics and potential clinical applications. Here, I propose for the first time the concept of a hierarchical system which is composed of all mesenchymal stem cells from post-embryonic subtotipotent stem cells to MSC progenitors. Post-embryonic subtotipotent stem cells are left-over cells during embryonic development and are on the top of the hierarchy. MSC system is a combination of cells that are derived from different stages of embryonic development, possess different differentiation potential and ultimately give rise to cells that share a similar set of phenotypic markers. The concept of MSC system has important implications: (1) it entirely explains the three important biological characteristics of MSC: stem cell properties of MSC, MSC as components of tissue microenvironment and immunomodulatory functions of MSC. (2) It balances immune responses and tissue metabolism. (3) It could provide tissue-specific stem cells for clinical application with high efficiency and safety. In a word, this concept constitutes an important part of the biological properties of MSC and will help researchers gain better insight into MSC.

[Study on inducing differentiation of human amniotic epithelial cells into insulin secreting cells in vitro]

OBJECTIVE

To investigate the differentiation of human amniotic epithelial cells (hAECs) into insulin secreting cells (ISCs) in vitro.

METHODS

The hAECs were isolated from human amnion by trypsin digestion, and the phenotype of the isolated cells were identified by flow cytometry and immunocytochemical staining. The hAECs at passage 3 were treated with nicotinamide and N2 supplement to investigate their differentiation into ISCs. At different times after differentiation, the expression of insulin and beta2 microglobulin (beta2-MG) was determined by immunocytochemical staining, while the content of insulin in supernatant from cultured hAECs was detected by radioimmunoassay and the expressions of insulin, pancreatic and duodenal homeobox factor-1 (PDX-1) mRNA were detected by reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

(1) hAECs expressed high percent of CD29, CD73, CD166 and CK19. (2) At 7, 14 and 21 days, the percentages of insulin-positive cells in induced groups were 74.00% +/- 1.73%, 75.33% +/- 1.15% (see symbol) 75.67% +/- 0.58% respectively, which were negative in control groups. (3) At 7, 14 and 21 days, contents of insulin in supernatant from induced groups were (328.47 +/- 3.22) microIU/ml, (332.26 +/- 1.22) microIU/ml and (329.68 +/- 2.57) microIU/ml respectively, they were significantly higher than those in control groups (All P < 0.01). (4) PDX-1 mRNA and beta2-MG were expressed before and after the induction of hAECs, but insulin mRNA was expressed only in the induced groups.

CONCLUSION

hAECs can differentiate into ISCs, having the potential application for therapy of type I diabetes.

[Virus free induction of umbilical cord derived mesenchymal stem cells into islet-like cells]

OBJECTIVE

To explore the feasibility of using a virus-free system in the induction of umbilical cord derived mesenchymal stem cells (UC-MSCs) into insulin-secreting cells.

METHODS

MSCs were isolated from human umbilical cord and induced into insulin-secreting cells with a three-stage method. The mRNA expression levels of foxa2, sox17, pdx1, ngn3, pax4, insulin, and glut-2 were compared between induced and non-induced groups by RT-PCR in each stage. The distribution pattern of insulin and c-peptide were detected by immunofluorescence staining and observed by fluorescence microscopy. Insulin and c-peptide secretion and glucose responsiveness were detected by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Transcription factors foxa2, sox17, pdx1, ngn3, pax4, insulin, and glut-2 were expressed in the induced cells. The mRNA expression levels of foxa2 and sox17 were significantly higher in the induced group than those in non-induced group in the first stage (all P < 0.05), pdx1, ngn3, and pax4 were significantly higher in the induced cells than those in non-induced cells in the second stage (all P < 0.05), and insulin and glut-2 expressions were significantly up-regulated in the induced group at last stage (all P < 0.05). Immunofluorescence staining showed that insulin and c-peptide were located in the cytoplasm of more than 90% of induced cells. ELISA showed that total intracellular insulin content of the induced cells contained up to (346.3 739 +/- 32.5 149) microU/ml, which was significantly higher than insulin in non-induced cells (17.69 +/- 1.46) microU/ml (P < 0.01). C-peptide content of the induced cells measured up to (195.10 +/- 8.88) pmol/L/h (P < 0.01), when exposed to 5.5 mmol/L glucose (P < 0.01). When stimulated with 22 mmol/L glucose, the c-peptide content of the induced cells increased to (340.99 +/- 7.91) pmol/L/h (P < 0.01 ).

CONCLUSION

The umbilical cord derived MSCs can be efficiently induced into insulin-secreting cells via a virus-free system.

A new cerebral hemorrhage model in cynomolgus macaques created by injection of autologous anticoagulated blood into the brain

The aim of this study was to establish and validate a clinically relevant model of intracerebral hemorrhage (ICH) via injection of autologous blood into the brains of cynomolgus macaques (Macaca fascicularis). Eight male cynomolgus macaques received 1.5 mL of fresh anticoagulated autologous femoral artery blood into the inner side of the claustrum near the right basal ganglia under stereotactic guidance. Animals were evaluated with MRI and positron emission tomography (PET) scanning before and 24 hours after surgery and once per week thereafter. A neurological deficit scale was used to assess the animals on days 1, 2, 3, 7, 14, 21, and 28 after surgery. Animals showed focal neurological signs corresponding to the MRI-located hematoma. The behavioral impairment progressively ameliorated over time, but never fully resolved. The hematoma was absorbed over time but was still present 4 weeks after surgery, with persistent metabolic deficit detected using PET scanning. Histological examinations confirmed the in vivo findings. This ICH model in a non-human primate mimics human ICH in the basal ganglia and may be useful for assessing the safety and efficacy of neuroprotective agents.

[Methylation of Id4 gene and inhibitive effect of arsenic trioxide on it in Raji cells]

OBJECTIVE

To study methylation of Id4 gene and demethylation effect of arsenic trioxide (ATO) in Raji cells.

METHODS

Human Burkitt's Raji lymphoma cells were cultared and treated with ATO at different concentrations and different time points. Methylated degree of Id4 gene was detected by methylation specificity polymerase chain reaction (MS-PCR), Id4 mRNA expression in Raji cell by reverse transcription polymerase chain reaction (RT-PCR), the growth of cell by MTT assay, and cell apoptosis and cycle distribution by Flow Cytometry (FCM).

RESULTS

(1) The Id4 gene exhaustive methylation in control group, and hypermethylation in experimental group were reversed by ATO in a dose-dependent manner. (2) Id4 mRNA expression in Raji cells treated with ATO for 48 h increased gradually with ATO concentration increasing in experimental group. (3) Raji cell growth inhibited rates after different concentrations of ATO treatment for 24, 48, 72 h were 12.15% ∼ 92.17% in the experimental group (P < 0.05). (4) Apoptosis peak emerged after ATO treatment for 48 hours in experimental group, while a much lower apoptosis in control group. (5) After ATO treatment for 48 h in experiment group, the cells were arrested at G(0)/G(1) phase in a dose-dependent manner.

CONCLUSION

Id4 gene presents exhaustive methylation in Raji cells. ATO can reverse the hypermethylation of Id4 gene and recover the expression of Id4 mRNA. Hypermethylation of Id4 gene is one of the reasons of Raji cells malignant proliferations.

Bioethanol production from hydrolysates of inulin and the tuber meal of Jerusalem artichoke by Saccharomyces sp. W0

It has been confirmed that Saccharomyces sp. W0 can produce high concentration of ethanol. However, this yeast strain cannot secrete inulinase. Therefore, in this study, inulin was hydrolyzed into reducing sugar by the recombinant inulinase produced by Pichia pastoris X-33/pPICZaA-INU1. It was found that 38.2U of the recombinant inulinase per gram of inulin was suitable for the inulin hydrolysis and ethanol production by Saccharomyces sp. W0 and the fermentation period was 120 h. At the end of the fermentation, over 14.6 ml of ethanol per 100ml of the fermented medium was produced, the ethanol productivity was over 0.384 g of ethanol/g of inulin and over 98.8% of total sugar was utilized. When the Saccharomyces sp. W0 was grown in the mixture of 4.0% hydrolysate of soybean meal and 20.0% of the hydrolysate of inulin for 120 h, over 14.9 ml of ethanol per 100ml of the fermented medium was yielded, the ethanol productivity was over 0.393 g of ethanol/g of inulin and 98.9% of total sugar was used by the yeast strain. When Saccharomyces sp. W0 carrying the same inulinase gene was grown in the medium containing 50 g of the tuber meal of Jerusalem artichoke per 100ml for 144 h, over 12.1+/-0.35%ml of ethanol per 100ml of the fermented medium was yielded, the ethanol productivity was 0.319+/-0.9 g of ethanol/g of sugar and 3.7% (w/v) of total sugar and 0.5% (w/v) of reducing sugar were left in the fermented media.

Mechanisms of the protective effects of BMSCs promoted by TMDR with heparinized bFGF-incorporated stent in pig model of acute myocardial ischemia

This study investigates the mechanism by which transmyocardial drilling revascularization combined with heparinized basic fibroblast growth factor incorporated degradable stent implantation (TMDRSI) enhanced effects of bone marrow mesenchymal stem cells (BMSCs) transplantation against acute ischemic myocardial injury. After the mid-third of left anterior descending artery was ligated, miniswine were divided into none-treatment group (control, n = 6), BMSCs implantation group (C, n = 6), TMDRSI group (TS, n = 6) and TMDRSI and BMSCs implantation group (TSC, n = 6). Two channels of 3.5 mm diameter were established by a self-made drill in the ischemic region, into which a stent was implanted for the TS and TSC groups. Autologous BMSCs were transplanted into the ischemic region in C group or around the channels in TSC group. Expression of von Willebrand factor, vascular endothelial growth factor, interleukin-1β, transforming growth factor-β₃, cell proliferation and apoptosis, histological and morphological analyses, myocardial remodelling and cardiac function were evaluated at different time-points. Six weeks after the operation, the above indices were significantly improved in TSC group compared with others (P < 0.05), though C and TS groups also showed better results than the control group (P < 0.05). The new method was shown to have activated paracrine pathway of transplanted BMSCs, increased survival and differentiation of such cells, and enhanced effects of BMSCs transplantation on myocardial remodelling, which may provide a new strategy for cell therapies against acute ischemic myocardial injury.

[Transfusion of mesenchymal stem cells combined with haploidentical HSCT improves hematopoietic microenvironment]

The aim of this study was to investigate the role of mesenchymal stem cells in the hematopoietic reconstitution of patients who had received haploidentical allogeneic hematopoietic stem cell transplantation (hi-allo-HSCT). 15 patients who underwent treatment with both MSCs and HSCs, were selected as study group, while 20 patients receiving only HSCT were taken as control. Bone marrow samples were obtained from iliac crest aspirates at several times after HSCT for the isolation, purification and expansion of MSCs. The confluent ratio and time were measured and compared with those of the control. The peripheral blood samples were obtained from patients, then absolute neutrophil and platelet counts were assayed. From day 4 before transplantation to day 28 after transplantation, serum was obtained every four days from patients of the two groups, and then 3 cytokines as SDF-1alpha, TPO and IL-11 were detected by ELISA. The results indicated that as compared with the control group, the ratio of primary confluent layer formation of MSCs in study group was obviously higher (27.3%) (p < 0.01), and the confluence time in culture was significantly less (p < 0.05). In the study group, the concentration of SDF-1alpha amounted to peak value (2975.19 +/- 681.56 pg/ml) on the 8th day after HSCT, which was obviously higher than that before HSCT (2403.70 +/- 522.39 pg/ml, p < 0.05), whereas in the control, the concentration of highest point of SDF-1alpha reached to peak valve (2280.60 +/- 701.25 pg/ml) on the 16th day after HSCT, which was less than that before HSCT (2701.46 +/- 483.21 pg/ml, p < 0.05). The concentration of TPO and IL-11 was higher in study group compared with the control from day 16 to 28 after HSCT (p < 0.05). It is concluded that the transfusion of MSCs combined with hi-all-HSCT may improve the injured state of the hematopoietic microenvironment in bone marrow of patients during allo-HSCT.

[Therapeutic efficacy of bone marrow-derived mesenchymal stem cells infused into mice with liver injury induced by concanavalin A]

The aim of this study was to evaluate the therapeutic potential of bone marrow mesenchymal stem cells (MSC) on acute liver injury induced by concanavalin A (ConA). MSCs were isolated from male C57BL/6 mice and cultured, and a ConA-induced acute liver injury model was used. MSCs were systemically infused immediately after mice were challenged with ConA, control mice received only saline infusion. 24 hours after MSC transplantation, the level of serum aminotransferases, histologic change and in situ apoptosis of cells were detected, the expression of inflammatory mediators were examined by real-time RT-PCR. The results indicated that MSC transplantation significantly reduced ConA-induced acute liver injury, including the decrease of the level of serum alanine aminotransferase (ALT), serum aspartate aminotransferase (AST) and the extenuation of liver necrosis and in situ apoptosis. Furthermore, after MSC infusion the expression of TNF-alpha, IFN-gamma in liver decreased greatly (p<0.05) with no statistical difference in the expression of iNOS, IL-2 and IL-10 (p>0.05). It is concluded that the systemic infusion of MSCs can alleviate ConA induced acute liver injury in mice.

A new transmyocardial degradable stent combined with growth factor, heparin, and stem cells in acute myocardial infarction

AIMS

We developed a new method-transmyocardial drilling revascularization (TMDR) with absorbable stent incorporated with basic fibroblast growth factor (bFGF) and heparin. The present study tested the effect of this method with transplantation of bone marrow-derived stem cells (BMSCs) in acute myocardial infarction.

METHODS AND RESULTS

Infarction was produced in mini-swine by ligating the left anterior descending (LAD) coronary artery. TMDR of 3.0 mm in diameter was made by mechanical drilling in the infarcted area. The animals that had LAD ligation were divided into six groups according to the procedures followed (n = 6 in each): control; T (TMDR); C (cell implantation); TS (TMDR+stent implantation); TC (TMDR+cell implantation); TSC (TMDR+stent implantation+cell implantation). Left ventricular (LV) function, myocardial perfusion, vascular density, and histological and morphological analyses were evaluated pre-operatively and at 30 min and 6 weeks post-operatively. Six weeks after operation, the above indices were significantly better in the TSC group than in other groups (P < 0.001 compared with the control group, and P < 0.05 or 0.01 compared with the TS and TC groups), although TS and TC also showed better results than the control group (P < 0.05).

CONCLUSION

We have demonstrated in a pig model that an intramyocardial stent implanted with slow release of bFGF, heparin, and BMSC transplantation may significantly increase LV function, cardiac blood flow, and vascular density. Therefore, the present study may provide a new method for the surgical treatment of myocardial infarction.

[Progress of study on the roles of matrix metalloproteinases in the pathogenesis of hematologic malignancies -- review]

Matrix metalloproteinases (MMPs) have the ability to degrade extracellular matrix components. They abnormally express in a variety of solid tumors and hematologic malignancies, and play an important role in tumor invasion and metastasis through extracellular matrix degradation, which closely relates with the progression and prognosis of the malignant disease. This article reviews progress of study on the mechanism of MMP underlying the pathogenesis of hematologic malignancies, including structure of MMP, regulation mechanism of MMP and its relation with proliferation and differentiation of hematopoietic stem cells (HSC), angiogenesis and tumor immunology and so on.

[Effect of total body irradiation on cellular senescence related indexes of bone marrow mesenchymal stem cells]

The aim of this study was to explore the changes in cellular senescence related indexes of bone marrow mesenchymal stem cells (BMMSCs) after total body irradiation (TBI). At different time points after 4 Gy irradiation, BMMSCs were isolated from male C57BL/6 mice and cultured. Morphology, senescence-associated beta-galactosidase (SA-beta-gal) staining and cell cycle analysis were used to evaluate the changes in BMMSCs at cellular level while real-time RT-PCR was used to detect the alterations in senescence related gene expression including p16INK4a, p21Cip1/Waf1, p53 and TGF-beta1. The results showed that within 4 weeks after exposure to 4 Gy TBI, the morphology of BMMSCs and the expression level of SA-beta-gal were not significantly changed, the cellular senescence-related cell cycle arrest was not occurred and the senescence related gene expression level was not increased. It is concluded that at the early stage after 4 Gy TBI, the related molecular level of cellular senescence in BMMSCs is not changed.

[Ferumoxide labeled Flk1+ CD31- CD34- human bone marrow mesenchymal stem cells and its in vivo tracing in the brains of Macaca Fascicularis]

OBJECTIVE

To explore the method for labeling Flk1+ CD31- CD34- human bone marrow mesenchymal stem cells (hBMSCs) with ferumoxide-PLL and evaluate the feasibility of its tracing after transplantation into the brains of Macaca Fascicularis.

METHODS

The hBMSCs were incubated with ferumoxide-PLL. Trypan blue staining, Prussian blue staining, and transmission electron microscope were performed to show intracellular iron, marking efficiency, and the vigor of the labeled cells. After the hBMSCs were transplanted into the brains of cynomolgus monkeys by stereotaxis, magnetic resonance imaging (MRI) was performed to trace the cells in vivo. Cell survival and differentiation were studied with immunohistochemistry, Prussian blue staining, and HE staining.

RESULTS

The marking efficiency of the ferumoxide-PLL was 96%. Iron particles were found intracytoplasmic of the hBMSCs by Prussian blue staining and transmission electron microscopy. The relaxation rates of labeled cells in MRI were 4.4 and 4.2 times higher than those of the unlabeled cells. Hypointensity area was found by MRI three weeks after transplantation. Many hBMSCs and new vessels were found in the transplantation zone by pathological and immunofluorescence methods.

CONCLUSIONS

Ferumoxide-PLL can effectively label hBMSCs and thus increase its contrast in MRI results. The cells can survive in the brains of cynomolgus monkeys. The labeled hBMSCs can be traced in vivo by MRI.

[Immuno-suppressive effects on T cells mediated by mesenchymal stem cells from patients with myelodysplastic syndrome]

The study was aimed to compare the effects of T-cell suppression mediated by mesenchymal stem cells (MSC) from normal individuals and myelodysplastic syndromes (MDS) patients. MSC were cultured from the bone marrow of 12 healthy volunteers and 12 MDS patients, the morphology, surface markers and expression of several cytokines of MSC from normal individuals and MDS patients were compared, and the effects of T-cell suppression were tested in the following assays: phytohemaglutinin (PHA)-primed cultures, mixed lymphocyte reaction (MLR), cell cycle of T-cell after PHA-primed cultures and apoptosis of T-cell as well. The results showed that the MSC from normal individuals and MDS patients were similar in morphology, proliferation and surface markers. The suppressions of T-cell proliferation induced by PHA and alloantigens mediated by MDS-MSC were significantly lower than that of normal MSC. More T-cells were arrested in G0/G1 phase by normal MSC, while the effects were deficient by MDS-MSC. The suppression of T-cell activation mediated by MDS-MSC was also lower than that of normal MSC, but suppression effect on T-cell apoptosis increased. The cytokines TGF-beta1, 3, FasL expressed by MDS-MSC were reduced as compared with normal MSC, but TGF-beta2 expression increased in MDS-MSC. It is concluded that although the morphology, proliferation and cell surface markers of MDS-MSC are normal, the T-cell suppression mediated by MDS-MSC is deficient as compared with normal controls. Whether these abnormalities are relevant to the pathogenesis of aplastic anemia remains to be determined.

Influence of wastewater composition on biological nutrient removal in UniFed SBR process

The effects of influent C/N ratio and C/P ratio on biological nutrient removal performance were investigated in a lab-scale UniFed SBR apparatus treating real domestic wastewater. The results showed that TN removal efficiency increased as C/N ratio increased from 43.6% at 2.8 to 80.8% at 5.7. But when C/N ratio increased further, TN removal efficiency increased very slowly. This was because when C/N ratio was higher than 5.7, complete denitrification in the sludge blanket during feed/decant period had been achieved, TN removal efficiency during this period always kept the maximum value and only TN removal efficiency during aeration period rose as C/N ratio increased. PO(4) (3-) removal efficiency increased as C/N ratio increased from 27.3% at 2.8 to 88.1% at 5.7. When C/N ratio was 6.5 and above, PO(4) (3-) concentration couldn't be detected in the effluent. When influent C/N ratio and volumetric exchange ratio were fixed at 6 and 33% respectively, as C/P ratio was higher than 33, PO(4) (3-) concentration of effluent always remained below the detection level and phosphorus removal efficiency kept stable at 100%, but as the C/P ratio was lower than 33, phosphorus removal efficiency increased as C/P ratio increased linearly. C/P ratio hardly affected TN removal efficiency, which always kept at 82.2%-85.8% in this study.

NsdB, a TPR-like-domain-containing protein negatively affecting production of antibiotics in Streptomyces coelicolor A3 (2)

Tetratricopeptide repeat (TPR) domains usually mediate protein-protein interactions. NsdA, one of the 70 proteins containing TPR-like domains in Streptomyces coelicolor A3 (2), was previously found to negatively control sporulation and antibiotic production. Here we show that elimination of SCO7252, which encodes another of these proteins, also caused overproduction of two antibiotics, actinorhodin and CDA, but did not affect morphological differentiation. Disruption of SCO1593, encoding another of the family, had no obvious phenotypic effects. In surface-grown cultures, expression of SCO7252, which was named nsdB, was initiated at about 30 h, like that of nsdA. Analysis in silico of the 70 predicted TPR-like-containing proteins of S. coelicolor showed that 32 of them contained only TPR-like domains, and 25 of the remainder contained additional DNA-binding domains, implying that they might control gene expression directly.

[Reduction of bone marrow mesenchymal stem/progenitor cells pool and alteration of their osteogenesis potential caused by total body irradiation]

To investigate the effect of irradiation on the quantity and osteogenesis potential of BMMSCs and to explore the response of them in the irradiation stress and its contribution to long-term effects of radiation-induced bone and hematologic injury, a total body irradiation (TBI) murine model was adopted. The number of CFU-F and cell cycle profile of BMMSCs were analyzed at different time points before and after TBI. Osteogenic differentiation was evaluated by Von Kossa staining, expressions of osteogenesis-related genes and transcriptional coactivator with PDZ-binding motif (TAZ) were detected by real-time RT-PCR. The results showed that the number of CFU-F decreased greatly at day 28 after TBI. At day 3 after TBI, more cells entered cell cycle and the osteogenesis potential was greatly enhanced followed by recovery of cell cycle distribution and significant defect in osteoblast differentiation respectively, meanwhile the expression of TAZ was changed. It is concluded that TBI results in the reduction of bone marrow mesenchymal stem/progenitor cell pool and alters the osteogenesis potential of BMMSCs, which is related to the change of TAZ expression.

[Effect of hypoxia on mesenchymal stem cells - review]

Oxygen is essential for life, but cultivation of cells is usually performed under 20% O(2), that do not replicate normal physiological hypoxia or pathological hypoxia conditions in the body. Recently, the effect of hypoxia on mesenchymal stem cells (MSCs) has been studied, under physiological hypoxia, MSCs thrive well, and the ability differentiating to osteoblast, chondrocyte and adipocyte as well as the ability of migration are changed. Hypoxia changes the physiological characteristics of embryonic stem cell, hematopoietic stem cell and neuron stem cell as well. The mechanism of these responses might be primarily involved in the hypoxic inducible factor-1 (HIF-1) signal pathway. This review emphasizes that hypoxia is an important factor on all major aspects of stem cell biology including survival, proliferation, differentiation, and migration, and the mechanism involved in HIF-1 signaling pathway behind these responses was also discussed.

6-Hydroxydopamine-induced alterations in blood-brain barrier permeability

Vascular inflammation is well known for its ability to compromise the function of the blood--brain barrier (BBB). Whether inflammation on the parenchymal side of the barrier, such as that associated with Parkinson's-like dopamine (DA) neuron lesions, similarly disrupts BBB function, is unknown. We assessed BBB integrity by examining the leakage of FITC-labeled albumin or horseradish peroxidase from the vasculature into parenchyma in animals exposed to the DA neurotoxin 6-hydroxydopamine (6OHDA). Unilateral injections of 6OHDA into the striatum or the medial forebrain bundle produced increased leakage in the ipsilateral substantia nigra and striatum 10 and 34 days following 6OHDA. Microglia were markedly activated and DA neurons were reduced by the lesions. The areas of BBB leakage were associated with increased expression of P-glycoprotein and beta 3-integrin expression suggesting, respectively, a compensatory response to inflammation and possible angiogenesis. Behavioural studies revealed that domperidone, a DA antagonist that normally does not cross the BBB, attenuated apomorphine-induced stereotypic behaviour in animals with 6OHDA lesions. This suggests that drugs which normally have no effect in brain can enter following Parkinson-like lesions. These data suggest that the events associated with DA neuron loss compromise BBB function.

[Flk1+ mesenchymal stem cells ameliorate carbon tetrachloride-induced liver fibrosis in mice]

Fibrosis is the common end stage of most liver diseases. Unfortunately, there is no effective treatment available currently. This study was designed to evaluate the effect of Flk1+ mesenchymal stem cells (MSC) from murine bone marrow (Flk1 + MSC) on fibrosis formation induced by carbon tetrachloride (CCl4). In this study Flk1+ MSC were isolated from bone marrow of male BALB/c mice. A CCl4 induced hepatic fibrosis model was used. Flk1+ MSC were systemically infused immediately or one week after the female mice were challenged with CCl4. Fibrosis index and donor cell engraftment were assessed two or five weeks after CCl4 challenge. We found that Flk1+ MSC transplantation immediately, but not one week after exposure to CCl4, significantly reduced CCl4-induced liver damage and collagen deposition. In addition, levels of hepatic hydroxyproline and serum fibrosis markers (HA, P-III-P) in mice receiving immediate Flk1+ MSC transplantation after CCl4 challenge were significantly lower compared to those of control mice. More importantly, histological examination suggested that hepatic damage recovery was much better in these immediately Flk1+ MSC-treated mice. Immunofluorescence, PCR, and fluorescence in situ hybridization (FISH) analysis revealed that donor cells engrafted into host liver, had epithelium-like morphology and expressed albumin (ALB), although at low frequency. In conclusion Flk1+ MSC might initiate endogenous hepatic tissue regeneration, engraft into host liver in response to CCl4 injury, and ameliorate its fibrogenic effects.

[Application of mesenchymal stem cell in immunotherapy--review]

There has been an increasing interest in recent years on mesenchymal stem cell (MSC). It is well known that MSCs are capable of self-renewal and differentiating into many cell lineages. MSC can be expended to a large quantity that is required for clinical transplantation. Recent studies show that MSC have potential application in immune diseases due to their unique immunologic characteristics, such as low immunogenicity and immunoregulatory function. But their immunoregulatory mechanism is not yet clear. This review discusses the advances in researches on the mechanism of MSCs' immunoregulatory function and potential clinical application in immune disease and organ transplantation.

[Inhibition effect of bone marrow mesenchymal stem cells on T-lymphocyte proliferation through up-regulation of CD8+CD28- T cells]

The aim of this study was to explore effect of CD8+CD28- T-lymphocyte in the inhibition of mesenchymal stem cells (MSC) on T-lymphocyte proliferation. T cells were harvested by using nylon column and CD8+ T cells were sorted by magnetic beads; the T-lymphocyte proliferation in the presence of PHA was evaluated by MTT; the proportion of CD8+CD28- T cells was assayed by fluorescence-activated cell sorter (FACS). The results showed that MSC inhibited T-lymphocyte proliferation and the inhibitory effect depended on the amount of MSC; the data of FACS indicated that in the CD8+ T cells co-cultured with MSC, CD8+CD28- T cells were up-regulated significantly, compared with the non-treated CD8+ T cells. In conclusion, MSC perform their immunosuppressive function by up-regulation of CD8+CD28- T cells.

[The effects of the Smad3-knockout on the hematopoiesis of mouse]

The effects of the Smad3- knockout on the hematopoiesis of mouse were investigated in this work. Five pairs of wild type and Smad3- null mice were studied. White blood cell(WBC), red blood cell(RBC) and platelet (PLT) counting of peripheral blood cells were performed with blood obtained from tails. And white blood cells were classified by their morphology. Bone marrow nucleated cells (BMNCs) were counted and classified. The CFU-GM, BFU-E, CFU-GEMM yields were measured in each pair of mice. CFU-S yield of each mouse was measured by injecting bone marrow cells into lethally irradiated 8-10 weeks old wild type female mice. And the pathomorphism of their bone marrows, spleens and livers were observed. As a result, WBC and PLT of Smad3- null mice were significantly higher than those in wild type mice. Smad3- null mice had much more proportion of granulocytes in classification. There wasn't any difference in RBC counting and BFU-E measurement. The yield of CFU-GM increased, while the yields of CFU-GEMM and CFU-S markedly reduced. Bone marrows are actively proliferative, with granulocytosis. The granulocyte/erythrocyte ratio increased. There were no obviously alterative in spleen and liver. Thus Smad3- knockout results in a decreased number of stem and progenitor cells. Moreover hematopoietic differentiation is abnormal with a tendency to forming more granulocytes and platelets. The effect of Smad3 on hematopoiesis is correlative to that of TGF-beta.

[Human umbilical cord blood hematopoietic stem/progenitor cells can grow up in the mouse liver]

The biological characterization, differentiation and regeneration of hepatic stem/progenitor cells are the one of very active and interested fields. In this report, intravenous injection of human umbilical cord blood (HUCB) cells into the BALB/c-nu and SCID mice, an animal model for transplantation and liver injury, was reported. Using of flow cytometry and tissue typing (HLA), it was found that the HUCB cells were survived in mouse liver for 9 weeks. After separation from perfused liver, HUCB cells were detected by hematopoietic colonies (CFU-GEM M) in hepatocyte culture. It was concluded that the transplanted HUCB hematopoietic stem/progenitor cells can be survived in the liver over a long period of time.

[Phenotypical and Biological Characteristics of Human Fetal Marrow and Liver Mesenchymal Stem Cells]

There has been an increasing interest in recent years in the stromal cell system. The stroma is a complex tissue, composed of a number vascular and connective tissue cell types including endothelial cells, adipocytes, smooth muscle cells, osteogenic cells, and stromal cells. The marrow mesenchymal stem cells are capable of self-renewal and differentiate into various connective tissue lineages including bone, cartilage, tendon, muscle, fat, and marrow stroma. Recently, techniques for the isolation of adult bone marrow-derived human and animal mesenchymal stem cells have been described, as well as the methods to directing their differentiation into osteogenic, chondrogenic, tendogenic, myogenic, adipogenic, and marrow stromal lineages. But there is no report about the fetal bone marrow- and liver-derived mesenchymal stem cells. Are they the same or not? In our assay, human fetal mesenchymal stem cells from 4 - 5 months old human fetal bone marrow and liver low-density mononuclear cells were cultured, and the cell cycle, immunophenotype and ex vivo expansion properties were studied. Results showed that the mesenchymal stem cells from fetal liver and fetal bone marrow were similar in morphology, growth character and immuno-phenotypes, but the liver mesenchymal cells manifested higher ability to support hematopoiesis than the marrow-derived mesenchymal cells. This study demonstrates that adherent fetal marrow- and liver-derived cells cultured in the absence of differentiation stimulus gave rise to a population of cells with phenotypical features of mesenchymal stem cells, and should be enough to sustain a steady supply of low differentiated cells upon proliferation.

Analysis of lactate dehydrogenase activities and isoenzyme patterns in colorectal cancer tissues

AIM: To investigate the relationship between lactate dehydrogenase (LDH) activity or LDH isoenzyme patterns and the pathogenesis of colorectal cancer.

METHODS: Activities of tissue LDH and LDH isoenzyme patterns in 16 patients with colorectal cancer were assayed using spectrophotometric procedures and agarose gel electrophoresis, respectively.

RESULTS: The total and specific activities of LDH were significantly higher in colorectal cancer tissues than those in adjacent noncancerous tissues (P < 0.001). The LDH isoenzyme pattern was also different from that in the control. The percentage of LDH₅ doubled and the ratio of LDH₄ + LDH₅/LDH₁ + LDH₂ was 3.6 ± 1.4 in cancer tissue, significantly greater than in the control.

CONCLUSIONS: The increased LDH activity in colorectal cancer tissues resulted mainly from the increased LDH₅, suggesting that the alteration of LDH activity and isoenzyme patterns were related to the pathogenesis of colorectal cancer.