[Research advances on biomaterials for the delivery of growth factors to regulate wound repair]

Wound repair is a highly coordinated and mutually regulated complex process involving various kinds of cells, extracellular matrices and cytokines. A variety of growth factors play an important regulatory role in wound healing, and it is critical to achieve effective delivery and sustained function of growth factors. In recent years, the application of biomaterials in tissue engineering has shown great potential, and the effective delivery of growth factors by biomaterials has attracted increasing attention. Based on this, this paper introduces the mechanism of related growth factors in the process of wound healing, focusing on the recent progress of biomaterial delivery of growth factors to accelerate wound healing, in order to provide new enlightenment for clinical wound treatment.

[Surveillance of human intestinal parasitic diseases in Nanping City from 2014 to 2018]

OBJECTIVE

To investigate the status of human intestinal parasitic diseases in Nanping City from 2014 to 2018, so as to provide reference for the development of the effective control measures.

METHODS

Administrative villages were selected using the two-stage cluster sampling in Nanping City from 2014 to 2018, and surveillance of human intestinal parasitic diseases was performed in 5 administrative villages in each county (district) of Nanping City. Intestinal parasitic infections were detected using a modified Kato-Katz thick smear method (two smears for a single stool sample) in villagers, and the hookworm species was differentiated. In addition, the eggs of Enterobius vermicularis were detected using the adhesive tape method in children aged 3 to 6 years.

RESULTS

A total of 6 317 villagers were detected in Nanping City from 2014 to 2018, and the overall prevalence of human intestinal parasitic infections was 2.15%. There was year- (χ² = 10.53, P < 0.05) and gender-specific prevalence of human intestinal parasitic infections in Nanping City during the study period (χ² = 17.00, P < 0.01). The prevalence of human intestinal parasitic infections increased with age, and there was age-specific prevalence of human intestinal parasitic infections in Nanping City (χ² = 102.62, P < 0.01). A total of 945 children at ages of 3 to 6 years were detected, and the prevalence of E. vermicularis infection was 3.28%.

CONCLUSIONS

The prevalence of human intestinal parasitic infections is at a low level in Nanping City from 2014 to 2018, and the infection mainly occurs in villagers of advanced age and low education levels. Further comprehensive measures are required to control intestinal parasitic infections in key populations.

Effect of night light regimen on growth performance, antioxidant status and health of broiler chickens from 1 to 21 days of age

Objective

The study was conducted to evaluate the effects of night light regimen on growth performance, antioxidant status and health of Lingnan Yellow broiler chickens from 1 to 21 days of age.

Methods

A completely randomized factorial design involved 2 photoperiods (constant lighting [CL], 24 L:0 D and intermittent lighting [INL], 17 L:3 D:1 L:3 D)×2 light intensities (10 lx and 30 lx). A total of one thousand six hundred and eighty 1-d-old Lingnan Yellow broiler chicks were randomly divided into 4 treatments with 6 replicates (70 birds per replicate). The experiment lasted for 21 d.

Results

Photoperiods and light intensities had no effect on average daily gain, feed conversion ratio, and mortality of the broiler chickens (p>0.05). The INL had a significant effect on average daily feed intake (p<0.05) of broiler chickens compared with CL. Photoperiod and light intensity had an interactive effect on melatonin (MT) concentration (p<0.05). At CL, reducing light intensity increased MT concentration; INL birds had higher MT but MT concentration was not affected by light intensity. There was an interactive effect on glutathione peroxidase (GPx) and catalase (CAT) in serum and total antioxidant capability (T-AOC) in liver between photoperiod and light intensity. With the decrease of light intensity, the activities of GPx and CAT in serum and T-AOC in liver increased in CL group (p<0.05). Broiler chickens reared under INL had better antioxidant status and 10 lx treatments had higher activities of CAT in serum than 30 lx (p<0.05). Different photoperiods and light intensities had no effect on malondialdehyde. There was an interaction between photoperiod and light intensity on serum creatine kinase (CK) concentration (p<0.05). At CL, the elevated light intensity resulted in an increase in CK content; INL birds had lower CK concentration especially in low light intensity group. Besides, INL and low light intensity significantly reduced the concentration of serum corticosterone and heat shock protein 70 (p<0.05). Serum immunoglobulin M contents were increased in broiler chickens reared under the INL compared with CL group (p<0.05).

Conclusion

Results above suggest that the night light regimen of INL and 10 lx could be beneficial to the broiler chickens from 1 to 21 days of age due to the better health status and electricity savings.

The identification of miR-375 as a potential biomarker in distal gastric adenocarcinoma

MicroRNAs (miRNAs) are endogenous small noncoding RNAs that negatively regulate gene expression at the posttranscriptional level and play an important role in carcinogenesis. Herein, we characterized the global expression of miRNA in distal gastric adenocarcinomas and determined if circulating miRNAs could be used as biomarkers for distal gastric adenocarcinoma. We used a microarray screening system to detect dysregulated miRNAs in distal gastric adenocarcinoma tissues. The expression of a subset of five aberrantly expressed miRNAs (miR-375, -196b, -204, -18b, and -93) were further quantified in an independent set of clinical samples of distal gastric adenocarcinoma by real-time quantitative RT-PCR (rt-qRT-PCR). We also used rt-qRT-PCR to investigate the expression levels of putative miRNA biomarkers in serum and tumor cell lines. In our study, the expression of a subset of microRNAs was altered in distal gastric adenocarcinoma compared to normal tissue, miR-375 was significantly downregulated in distal gastric adenocarcinoma tissues, to a level that was significantly lower than cardia adenocarcinoma (p < 0.05). The circulating serum levels of miR-375 in patients who had distal gastric adenocarcinoma were also much lower than normal controls (p < 0.001). As a biomarker, miR-375 yielded a receiver operating characteristic area under the curve of 0.835. The specificity and sensitivity was 80% and 85%, respectively, in the discrimination of distal gastric adenocarcinoma from control, at a normalized cutoff of 0.218. The expression of miR-375 was downregulated both in distal gastric adenocarcinoma tissues and serum of patients with distal gastric adenocarcinoma. These data suggest miR-375 is a potential biomarker for distal gastric adenocarcinoma.

Oxymatrine liposome attenuates hepatic fibrosis via targeting hepatic stellate cells

AIM: To investigate the potential mechanism of Arg-Gly-Asp (RGD) peptide-labeled liposome loading oxymatrine (OM) therapy in CCl₄-induced hepatic fibrosis in rats.

METHODS: We constructed a rat model of CCl₄-induced hepatic fibrosis and treated the rats with different formulations of OM. To evaluate the antifibrotic effect of OM, we detected levels of alkaline phosphatase, hepatic histopathology (hematoxylin and eosin stain and Masson staining) and fibrosis-related gene expression of matrix metallopeptidase (MMP)-2, tissue inhibitor of metalloproteinase (TIMP)-1 as well as type I procollagen via quantitative real-time polymerase chain reaction. To detect cell viability and apoptosis of hepatic stellate cells (HSCs), we performed 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide assay and flow cytometry. To reinforce the combination of oxymatrine with HSCs, we constructed fluorescein-isothiocyanate-conjugated Arg-Gly-Asp peptide-labeled liposomes loading OM, and its targeting of HSCs was examined by fluorescent microscopy.

RESULTS: OM attenuated CCl₄-induced hepatic fibrosis, as defined by reducing serum alkaline phosphatase (344.47 ± 27.52 U/L vs 550.69 ± 43.78 U/L, P < 0.05), attenuating liver injury and improving collagen deposits (2.36% ± 0.09% vs 7.70% ± 0.60%, P < 0.05) and downregulating fibrosis-related gene expression, that is, MMP-2, TIMP-1 and type I procollagen (P < 0.05). OM inhibited cell viability and induced apoptosis of HSCs in vitro. RGD promoted OM targeting of HSCs and enhanced the therapeutic effect of OM in terms of serum alkaline phosphatase (272.51 ± 19.55 U/L vs 344.47 ± 27.52 U/L, P < 0.05), liver injury, collagen deposits (0.26% ± 0.09% vs 2.36% ± 0.09%, P < 0.05) and downregulating fibrosis-related gene expression, that is, MMP-2, TIMP-1 and type I procollagen (P < 0.05). Moreover, in vitro assay demonstrated that RGD enhanced the effect of OM on HSC viability and apoptosis.

CONCLUSION: OM attenuated hepatic fibrosis by inhibiting viability and inducing apoptosis of HSCs. The RGD-labeled formulation enhanced the targeting efficiency for HSCs and the therapeutic effect.

Integrin alphavbeta6 promotes tumor tolerance in colorectal cancer

Tumor immune tolerance plays a critical role in tumor cell survival; the establishment of tumor immune tolerance is incompletely understood yet. Integrin alphavbeta6 (avb6) is involved in tumor growth and metastasis. This study aimed to observe the effect of avb6 on the development of tumor tolerance in colorectal cancer (CRC). In this study, 28 CRC patients were recruited. The frequencies of tolerogenic dendritic cells (TolDC), regulatory T cells (Treg), and CD8+ T cells in surgically removed CRC tissue were assessed by flow cytometry. The levels of avb6 in CRC tissue were measured by enzyme-linked immunoassay (ELISA). The effect of avb6 on inducing TolDCs and Tregs was evaluated with the cell culture model. The results showed that in surgically removed CRC tissue, we detected higher frequencies of TolDC and Tregs, lower frequency CD8+ T cells and high levels of avb6 as compared with non-CRC tissue. CRC protein extracts could induce TolDC development that could be blocked by anti-avb6 antibody. CRC-derived DCs could convert naïve CD4+ T cells to Tregs. Peripheral CD8+ T cells from CRC patients still retained the ability to produce granzyme B and to proliferate in response to CRC tumor antigen in culture that was abolished by the presence of CRC-derived Tregs. We conclude that CRC-derived avb6 is involved in the establishment of tumor immune tolerance in local tissues.

Resistin level is positively correlated with thrombotic complications in Southern Chinese metabolic syndrome patients

BACKGROUND

The metabolic syndrome (MetS) has been found to be closely related with thrombotic diseases. The mechanism, however, is far from elucidated.

AIM

This study was designed to investigate the relationship between endogenous resistin and thrombosis mediating factors, as well as its potential effects on the gene expression of cardiovascular disease biomarkers.

METHODS

Ninety patients satisfied the MetS criteria, and 55 healthy subjects were recruited as part of a single-center clinical study. Plasma levels of resistin, tissue factor (TF), tissue factor pathway inhibitor (TFPI), tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1) were measured by enzymelinked immunosorbent assays. The effect of resistin on the expression of cardiovascular disease biomarkers in human umbilical vein endothelial cells (HUVEC) was assayed by gene microarray.

RESULTS

1) The average levels of resistin in MetS patients with or without acute myocardial or cerebral infarction were significantly higher than those of the controls. 2) The TF and TFPI increase was higher in MetS with infarction patients than in MetS patients. 3) In MetS with infarction patients, resistin was positively correlated with TF and PAI-1 (r=0.313, p=0.008; r=0.401, p=0.002, respectively). 4) In HUVEC, the microarray showed that apolipoprotein C-I, ACE, tumor necrosis factor receptor superfamily member 1A (TNFRSF1A) and member 5 (CD40) genes expression were dramatically increased by resistin.

CONCLUSION

In patients with MetS, resistin is strongly associated with hypercoagulative and hypofibrinolitic activities. Moreover, resistin may induce thrombotic complications via mediating the lipoprotein metabolism and stimulating inflammation.

Immunoglobulin kappa and immunoglobulin lambda are required for expression of the anti-apoptotic molecule Bcl-xL in human colorectal cancer tissue

OBJECTIVE

Aberrant expression of immunoglobulin (Ig) by cancer cells has been documented in a number of malignant tumors but its biological significance is unclear. Cancer cells overexpress anti-apoptotic molecules such as Bcl-xL. The present study aimed to examine the role of expression of Ig light-chain Igk and Iglambda in maintaining the high levels of Bcl-xL in colorectal cancer cells.

MATERIAL AND METHODS

Thirty patients with colorectal cancer were recruited to this study. Expression of Igk, Iglambda and Bcl-xL in surgically removed cancer tissue was examined by immunohistochemistry and/or flow cytometry. Using the HT29 cell line as a study platform, RNA interference (RNAi) was employed to knock out the genes of Igk and Iglambda in the cancer cell line; the expression of Bcl-xL in HT29 cells was subsequently analyzed.

RESULTS

Human colorectal cancer cells, but not normal colorectal tissue, expressed both Igk and Iglambda in the cytoplasm. High levels of Bcl-xL were detected in cancer cells. Using RNAi to knock out the genes of Igk and/or Iglambda, Bcl-xL expression in HT29 cells was significantly suppressed and the cells became apoptotic.

CONCLUSION

The results suggest that expression of Igk and Iglambda is required to stabilize Bcl-xL expression in cancer cells.

Solid gastric emptying and mental analysis in elderly patients with reflux esophagitis

AIM: To study the function of solid gastric emptying in elderly patients with reflux esophagitis (RE) and its correlative factors and provide evidence for clinical diagnosis and treatments.

METHODS: The solid gastric emptying of RE patients (n = 33) was checked by ¹³C-octanoic acid breath test. All the patients had been classified by endoscopy according the standard made on Yantai conference in 1999. The symptoms were scored and the mental factors were evaluated through Zung's self-rating depression scale.

RESULTS: The half gastric emptying time (T1/2) and lag phase time (Tlag) in RE patients were both obviously higher than those in the controls (t = 7.51, P < 0.01; t = 9.42, P < 0.01), and the values of T1/2 and Tlag in patients with more than 6 scores were also markedly higher than those with less than 6 scores (t = 4.01, P < 0.01; t = 9.42, P < 0.01). However, no significant difference was found between endoscopicⅠand Ⅱ+Ⅲ grade in T1/2 and Tlag. The melancholy and anxiety score in RE patients were significantly higher than those in the controls (56.8 ± 12.3 vs 39.6 ± 9.8, P < 0.01; 53.4 ± 10.9 vs 37.7 ± 11.5, P < 0.01).

CONCLUSION: The solid gastric emptying in elderly RE patients is significantly delayed, which is correlated with the symptom scores but not endoscopic grades. Melancholy and anxiety commonly exist in elderly RE patients.

Early diagnosis and treatment of multiple primary malignant tumors in gastrointestinal tract in the elderly

AIM

To explore and investigate the experience of early diagnosis and treatment with multiple primary malignant tumors in the elderly.

METHODS

Fifty-nine cases of PMPTs patients admitted to our hospital in the period of 1980 to 2002 were studied retrospectively, including early dignosis, the 5-and 10-year survival rates in first and second cancer after endoscopic mucosal resection, resection and radiotherapy, the interval time between sequential tumors and proper treatment.

RESULTS

Eleven (19%) patients had synchronous tumors and 48 (81%) patients had metachronous tumors, of these, double cancer, triple cancer in the gastrointestinal tract were 26 cases and 7 cases, respectively. Early diagnosis in patients with PMPT in double and triple primary cancers in gastrointestinal tract were 58% and 38% respectively. The interval time between the cancers varied between 6 months and 21 years. The median interval time was 48 months, and that between second and third was 60 months. The 5 year survival rates from the date of the treatment of the first cancer were 75%(9/12), for those who had endoscopic mucosal resection, and 67% (14/21), for those who received radical operation and 64%(7/11), for radiotherapy respectively. The 10 year survival rates were 41%(5/12) 38%(8/21) 27% (3/11) respevtively.

CONCLUSION

Early dignosis of MPT elevated 5-year survival rates. Endoscopic treatment was recommened for early stage carcinomas of the gastrointestinal tract in the elderly.