MiR-381-3p inhibits proliferation, migration and invasion by targeting LRP6 in papillary thyroid carcinoma

OBJECTIVE

MiR-381-3p plays an essential role in the progression of a variety of cancers, but its expression and role in papillary thyroid carcinoma (PTC) progression have not been investigated. The aim of this study was to investigate the expression of miR-381-3p and its function in PTC.

PATIENTS AND METHODS

The expression levels of miR-381-3p and low-density lipoprotein receptor‑related protein 6 (LRP6) mRNA in PTC tissues and cell lines were measured using RT-PCR. Cell proliferation, migration and invasion were assessed by cell viability assay and transwell assay. Luciferase assays and Western blotting were performed to demonstrate miR-381-3p target gene.

RESULTS

We found that miR-381-3p was significantly down-regulated in PTC tissues and cell lines. In vitro assay indicated that up-regulation of miR-381-3p significantly suppressed PTC cell proliferation, migration and invasion. Moreover, luciferase reporter gene assay demonstrated that miR-381-3p could target LRP6 by binding to the 3' UTR. Western blot and Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) showed that miR-381-3p overexpression suppressed the expression of LRP6 at both mRNA and proteins levels. In addition, functional experiment confirmed that LRP6 was involved in the suppressive effect of miR-381-3p-mediated PTC on cell proliferation, migration and invasion.

CONCLUSIONS

Our findings suggested, for the first time, that miR-381-3p was lowly expressed in PTC tissues, and its up-regulation inhibited tumorigenesis of PTC by targeting LRP6.

[The Role of CBS in Injury Time Estimation after Brain Contusion]

OBJECTIVES

To observe the changes of cystathionine β-synthase （CBS） expression in the cerebral cortex after brain contusion at different times.

METHODS

An experimental model of traumatic brain injury （TBI） in mice was established by an improved weight-drop device. Then Western blotting and immunohistochemical examination were used to detect the CBS expression in cerebral cortex around injury at different time points （1 h, 6 h, 12 h, 1 d, 2 d, 3 d, 7 d）.

RESULTS

The results of Western blotting revealed that the expression level of CBS was down-regulated and reached its lowest level at the 3rd days after injury, and then restored to normal level after 7 days. The results of immunohistochemistry showed that CBS was present in the normal brain cortex. CBS expression gradually decreased at the 3rd days after injury, and then restored to normal level after 7 days.

CONCLUSIONS

CBS has the potential to be a reference index for time estimation after brain contusion in forensic practice.

The role of mitochondrial DNA mutations in a Han Chinese population on sepsis pathogenesis

OBJECTIVE

Individual susceptibility to sepsis has received increasing attention in recent years, and the study of genetic variations has become a hotspot regarding sepsis pathogenesis. We, therefore, investigated the association between mitochondrial genotype and sepsis susceptibility.

PATIENTS AND METHODS

One hundred patients admitted with sepsis and registered by five intensive care units (ICUs) in the People's Liberation Army Hospital and the Beijing Aerospace Center Hospital between January 2015 and January 2016 were enrolled as a case group, and 100 healthy persons were recruited as a control group. Patients' general information was obtained, and clinical evaluations and mitochondrial sequence screening were performed.

RESULTS

A total of 718 single nucleotide polymorphisms (SNPs) were detected in 708 loci in 100 patients. There were 1754 mutations in 456 loci in the coding region and 567 mutations were found in the RNA region. A total of 34 loci (from 40 cases) were novel mutations. A10398G (52.52%), C5178A (24.24%), C150T (17.17%), G3010A (17.17%), and T16189C (16.16%) were the most frequently observed conserved non-synonymous mutations that were differently expressed between the case and control groups (p<0.05). A5863T and C3270 deletion mutations were located on the genes encoding tRNATyr and tRNALeu, respectively. Small changes in the tRNA gene were likely to result in protein level changes.

CONCLUSIONS

We suggest that mitochondrial SNPs may be associated with the pathogenesis of sepsis.

The role of the hippocampus and the function of calcitonin gene-related peptide in the mechanism of traumatic brain injury accelerating fracture-healing

OBJECTIVE

This research attempts to identify the part the hippocampus plays in accelerated fracture-healing after traumatic brain injury as well as to test functions of calcitonin gene-related peptide (CGRP) during this process.

MATERIALS AND METHODS

Experiments were carried out on Male Sprague-Dawley rats that were split into four groups at random: TBI-fracture group, fracture-only group, TBI-only group, and control group. In the first week, blood specimen would be drawn from rats among the groups except those of the control group at three-time points (24, 72 and 168 hours) post-damage. These rats would be assessed from the neurological perspective based on their grades of performance in a sequence of tests 24 hours before and 12 hours after brain injury. Blood samples were also taken from the control group 24 hours before the injury, and whole brain tissues in the injured groups were harvested at 72 and 168 hours post-injury. We compared the serum CGRP concentration, the distribution of CGRP, the CGRP expression, and the expression of CGRP in the hippocampus, the expression of CGRP in the hippocampus, the expression of CGRP in the hippocampus, and the expression of CGRP in the brain by immunohistochemistry, Western blotting, RT- Of CGRP RNA expression levels.

RESULTS

Neurological examinations suggested that the functions of the cerebral cortex, cerebellum, and brain stem showed significant differences pre- and post-injury (p < 0.001). ELISA analysis indicated a great density of CGRP in TBI-fracture group at different time points. Furthermore, in the TBI-fracture group, CGRP in both hippocampus and the whole brain showed a noticeable augment in RT-PCR and western blot analysis at 72 and 168 h post-injury, and only in this group, immunohistochemistry analysis indicated that CGRP was present in the hippocampus at 168 hours post-injury.

CONCLUSIONS

We observed that the hippocampus and CGRP were responsible for quick bone-healing mechanisms. We suggest a role for the hippocampus in accelerated fracture healing. CGRP expression, as determined by IHC, cannot be observed in other groups, indicating that the hippocampus may be the specific component of the brain that responds to "big stress".

A novel scale-down cell culture and imaging design for the mechanistic insight of cell colonisation within porous substrate

At the core of translational challenges in tissue engineering is the mechanistic understanding of the underpinning biological processes and the complex relationships among components at different levels, which is a challenging task due to the limitations of current tissue culture and assessment methodologies. Therefore, we proposed a novel scale-down strategy to deconstruct complex biomatrices into elementary building blocks, which were resembled by thin modular substrate and then evaluated separately in miniaturised bioreactors using various conventional microscopes. In order to investigate cell colonisation within porous substrate in this proof-of-concept study, TEM specimen supporters (10-30 μm thick) with fine controlled open pores (100∼600 μm) were selected as the modular porous substrate and suspended in 3D printed bioreactor systems. Noninvasive imaging of human dermal fibroblasts cultured on these free-standing substrate using optical microscopes illustrated the complicated dynamic processes used by both individual and coordinated cells to bridge and segment porous structures. Further in situ analysis via SEM and TEM provided high-quality micrographs of cell-cell and cell-scaffold interactions at microscale, depicted cytoskeletal structures in stretched and relaxed areas at nanoscale. Thus this novel scaled-down design was able to improve our mechanistic understanding of tissue formation not only at single- and multiple-cell levels, but also at micro- and nanoscales, which could be difficult to obtain using other methods.

[Studies on chemical constituents of Bletilla striata (Thunb) Reichb. f]

OBJECTIVE

To study the chemical constituents of Bletilla striata.

METHOD

The constituents were separated and purified by column chromatography with silica gel, and identified by NMR, MS and physical data.

RESULT

Three compounds were isolated and identified as hexacosanoic alcohol 3-(4-hydroxy-3-methoxybenzol)-trans-acryliceylenate(1), physcion(2) and cyclobalanol(3).

CONCLUSION

Compound 1 was a new compound and compound 3 was isolated from this plant for the first time.

Control of Aedes aegypti larvae in household water containers by Chinese cat fish

In 1980-81 an outbreak of dengue fever occurred in Guangdong province and in Guangxi-Zhuang autonomous region in the central-southern part of China. Subsequently, a nationwide survey indicated that the vector of the disease, Aedes aegypti, was confined to the coastal strip of Guangdong and Guangxi-Zhuang. Since the first case in the outbreak occurred in Guangxi-Zhuang, a community-based programme to control A. aegypti was set up in eight fishing villages of this region where the mosquito was breeding in household water containers. The principal method of control was use of the indigenous edible fish Clarias fuscus (Chinese cat fish), which is highly larvivorous and tolerant of harsh environmental conditions. Each container was stocked with a young fish, which could survive there for periods of up to a year. A team of primary medical personnel (barefoot doctors) made sure that the programme was correctly implemented. The programme was monitored from 1981 to 1985 in three of the villages, and the results indicated that the Breteau index remained at a low level throughout this period.