[Research Progress of MALDI-TOF-IMS in Biomedicine and Its Application Prospect in Forensic Sciences]

Matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry （MALDI-TOF-IMS） can analysis unknown compounds in sections and obtain molecule imaging by scanning biological tissue sections, which has become a powerful tool for the research of biomarker, lipid distribution and drug metabolism, etc. This article reviews the application of this technique in protein identification, clinical application, drug discovery, lipid research and brain injury.

[Diagnostic Value of Postmortem CT Angiography in Coronary Atherosclerosis]

OBJECTIVES

To explore the application value of postmortem computed tomography （CT） angiography on diagnosis of coronary atherosclerotic stenosis degree.

METHODS

Based on the previous experimental results, the postmortem CT angiography device of human isolated heart was improved. Different coronary atherosclerotic stenosis degree of sudden death cases was selected. Before the cardiac anatomy, hearts were removed out completely and CT angiography was performed immediately. The CT angiography results were compared with histopathological findings. Meanwhile, the advantages and disadvantages of the angiography device before and after improvement were compared.

RESULTS

The improved angiography device of isolated heart could get better imaging results. The postmortem CT angiography results had high consistency with the histopathological findings on diagnosis of coronary atherosclerotic stenosis degree. And the coronary artery lesions could be revealed more objectively and vividly by 3D reconstruction technology. However, CT angiography could only be used to examine the pathological changes of blood vessels, which might have some limitations on the diagnosis of cause of death.

CONCLUSIONS

Postmortem CT angiography can be used as an additional method for the conventional autopsy in the cases of coronary atherosclerosis.

Intrinsically patterned two-dimensional materials for selective adsorption of molecules and nanoclusters

Two-dimensional (2D) materials have been studied extensively as monolayers, vertical or lateral heterostructures. To achieve functionalization, monolayers are often patterned using soft lithography and selectively decorated with molecules. Here we demonstrate the growth of a family of 2D materials that are intrinsically patterned. We demonstrate that a monolayer of PtSe₂ can be grown on a Pt substrate in the form of a triangular pattern of alternating 1T and 1H phases. Moreover, we show that, in a monolayer of CuSe grown on a Cu substrate, strain relaxation leads to periodic patterns of triangular nanopores with uniform size. Adsorption of different species at preferred pattern sites is also achieved, demonstrating that these materials can serve as templates for selective self-assembly of molecules or nanoclusters, as well as for the functionalization of the same substrate with two different species.

Horizontal transfer and functional evaluation of high pathogenicity islands in Avian Escherichia coli

High pathogenicity islands (HPIs) inEscherichia coliencode genes that are primarily involved in iron uptake and regulation, and confer virulence and pathogenicity. The aim of this study was to investigate the transfer ofHPIs in avianE. coliand identify the function ofHPIin the acceptor strain. TheHPItransfer strain was obtained under conditions of low temperature and low iron abundance, and the donor and acceptor strains were confirmed.E. coli HPIs are transferred by horizontal gene transfer events, which are likely mediated primarily by homologous recombination inHPI-adjacent sequences. Assays for biological activity and pathogenicity changes in the acceptor strain indicated thatHPIs might not be involved in pathogenesis in avianE. coli, and thus the main function ofHPIs in this strain of bacteria may be to regulate iron nutrition.

[Application of MOAS for Evaluating of Violence Risk in the Inpatients with Mental Disorders]

OBJECTIVES

To explore the value of Modified Overt Aggression Scale （MOAS） on predicting serious aggressive behavior in the inpatients with mental disorders and to provide theoretical basis for violence risk assessments in the inpatients with mental disorders.

METHODS

Total 918 inpatients in a psychiatric hospital were evaluated by trained medical workers using MOAS in September 2009, and their serious violent behavior were followed up for 2 years. The value of MOAS on predicting violence in the inpatients with mental disorders was analyzed by SPSS 21.0.

RESULTS

（1） Compared to the patients without serious aggressive behaviors, the patients with serious aggressive behavior within 2 years showed significantly higher scores （P＜0.05） on verbal aggression, aggression against property, physical aggression and total weighted score of MOAS; （2） Significant correlation was found between the score of verbal aggression and the serious acts of violence within 2 years （P＜0.05）; （3） Scores of verbal aggression, physical aggression and total weighted score of MOAS had predictive value on serious aggressive behaviors within 2 years.

CONCLUSIONS

MOAS has certain value on predicting the serious aggressive behaviors of patients with mental disorders within 2 years.

Molecular basis of retinol anti-ageing properties in naturally aged human skin in vivo

OBJECTIVE

Retinoic acid has been shown to improve the aged-appearing skin. However, less is known about the anti-ageing effects of retinol (ROL, vitamin A), a precursor of retinoic acid, in aged human skin in vivo. This study aimed to investigate the molecular basis of ROL anti-ageing properties in naturally aged human skin in vivo.

METHODS

Sun-protected buttock skin (76 ± 6 years old, n = 12) was topically treated with 0.4% ROL and its vehicle for 7 days. The effects of topical ROL on skin epidermis and dermis were evaluated by immunohistochemistry, in situ hybridization, Northern analysis, real-time RT-PCR and Western analysis. Collagen fibrils nanoscale structure and surface topology were analysed by atomic force microscopy.

RESULTS

Topical ROL shows remarkable anti-ageing effects through three major types of skin cells: epidermal keratinocytes, dermal endothelial cells and fibroblasts. Topical ROL significantly increased epidermal thickness by stimulating keratinocytes proliferation and upregulation of c-Jun transcription factor. In addition to epidermal changes, topical ROL significantly improved dermal extracellular matrix (ECM) microenvironment; increasing dermal vascularity by stimulating endothelial cells proliferation and ECM production (type I collagen, fibronectin and elastin) by activating dermal fibroblasts. Topical ROL also stimulates TGF-β/CTGF pathway, the major regulator of ECM homeostasis, and thus enriched the deposition of ECM in aged human skin in vivo. 0.4% topical ROL achieved similar results as seen with topical retinoic acid, the biologically active form of ROL, without causing noticeable signs of retinoid side effects.

CONCLUSION

0.4% topical ROL shows remarkable anti-ageing effects through improvement of the homeostasis of epidermis and dermis by stimulating the proliferation of keratinocytes and endothelial cells, and activating dermal fibroblasts. These data provide evidence that 0.4% topical ROL is a promising and safe treatment to improve the naturally aged human skin.

The use of optical coherence tomography (OCT) to evaluate the efficacy of different photo-coagulations in diabetic macular edema treatment

OBJECTIVE

To evaluate the therapeutic effects of the early application of photocoagulation for treating the macular edema in non-proliferative diabetic retinopathy (NPDR). We also wanted to evaluate the potential of optical coherence tomography (OCT) to make a quantitative detection in patients suffering from this condition.

PATIENTS AND METHODS

From October 2010 to October 2014, a total of 132 patients, all diagnosed with NPDR combined with clinically significant macular edema (CSME) in our hospital, were enrolled in this study. After obtaining the approval of the hospital Ethics Committee and the informed consents of patients and families, we divided the cases into two groups: PRP group (n=63) and macular edema group (n=69). Clinical effects and complications associated with the used methods were compared and analyzed in two groups.

RESULTS

We analyzed the panretinal photocoagulation (PRP), and macular grid photocoagulation curative effects. The difference in successful surgery rate, between the two groups, was not statistically significant (p > 0.05). When we examined patients 1 month, 3 months, and 6 months after the surgery, average retinal thickness and volume in macular region in both groups were reduced. In the group, the comparison was statistically significant (p < 0.05) while between the groups, the comparison was not statistically significant (p > 0.05). Visions in both groups were improved after treatment and difference on the post-operative 6-month vision improvement degree between the two groups was not statistically significant (p > 0.05).

CONCLUSIONS

We concluded that the early photocoagulation could significantly improve the vision. However, the clinical effects and complications associated with the use of PRP and macular grid photocoagulation had no significant differences.

The promoter polymorphisms of receptor for advanced glycation end products were associated with the susceptibility and progression of sepsis

Receptor for advanced glycation end products (RAGE) is considered a major pattern recognition receptor, which plays an important role in the development of sepsis. Increasing evidence showed an association between RAGE polymorphisms and the susceptibility to several inflammatory-related diseases. However, little is known about the clinical relationship between RAGE polymorphisms and sepsis. In this study, we analyzed the association of sepsis with three functional RAGE gene polymorphisms (rs1800624, rs1800625 and rs2070600) in a Chinese Han population (372 sepsis cases and 400 healthy controls). Significant differences were observed in the rs1800624 and rs1800625 genotype/allele distributions between the sepsis and controls, but no significant difference was observed in the rs2070600 genotype/allele. Moreover, our results also revealed a significant difference in the genotype/allele frequencies of the rs1800624 and rs1800625 polymorphisms between the sepsis and severe sepsis subtypes, the rs1800624 TT or rs1800625 TT genotype carriers exhibited a significant increase in RAGE mRNA, sRAGE, TNF-α and IL-6 expression compared with the rs1800624 AT/AA or rs1800625 CT/CC carriers in sepsis patients. Overall, this study might provide valuable clinical evidence between the RAGE gene polymorphisms and the risk or the development of sepsis.

Evaluation of the GenoType(®) MTBDRplus line probe assay on sputum-positive samples in routine settings in China

BACKGROUND

Rapid molecular methods have been recommended for early detection of drug-resistant tuberculosis (TB).

OBJECTIVE

To evaluate the performance of the GenoType(®) MTBDRplus assay in routine settings in China.

METHODS

Sputum-positive samples were collected consecutively from 1 April to 31 December 2010. MTBDRplus results were compared to those of conventional drug susceptibility testing (DST). The McNemar χ(2) test and κ coefficient were used to assess performance.

RESULTS

Of 427 smear-positive sputum samples collected, conventional DST and MTBDTplus confirmed drug resistance in 326. The sensitivities and specificities for MTBDRplus in detecting isoniazid (INH) and rifampicin (RMP) resistance were respectively 76.47%, 95.44%, 85.94% and 93.13%. The McNemar χ(2) test indicated no significant difference between the two methods (P = 0.106 for INH and P = 0.083 for RMP). The κ values for INH, RMP and multidrug resistance were respectively 0.75, 0.75 and 0.70.

CONCLUSIONS

Although the MTBDRplus assay was moderately concordant with conventional DST in detecting INH and RMP resistance, as a prospective rapid molecular method for MDR-TB detection, potential resistant mutations need to be incorporated to improve the accuracy of detection.

Role of vitamin D receptor gene polymorphisms in aplastic anemia: a case-control study from China

INTRODUCTION

Vitamin D receptor (VDR) gene and its polymorphisms are highlighted as candidate components for susceptibility to various autoimmune diseases. The aim of this study was to investigate the role of VDR polymorphisms (rs2228570, rs1544410, rs7975232, and rs731236) in aplastic anemia (AA).

METHODS

In this case-control study, the genotyping of VDR rs1544410 (c.1024 + 283G>A), rs7975232 (c.1025-49G>T), and rs731236 (c.1056T>C) polymorphisms was conducted using polymerase chain reaction (PCR)-ligase detection reaction, while the genotyping of rs2228570 (c.2T>C) was detected by PCR-restriction fragment length polymorphism.

RESULTS

The frequencies of GG genotype and G allele of rs1544410 were significantly higher in patients with AA than in controls. Further analysis indicated that rs1544410 and rs7975232 polymorphisms were correlated with the risk to nonsevere AA, while rs2228570 was relevant to severe AA. Moreover, TT carriers of rs2228570 were closely associated with a poor response to treatment and a higher risk of myelodysplastic syndrome/acute leukemia transformation, while CT carriers more easily evolved to overt paroxysmal nocturnal hemoglobinuria.

CONCLUSIONS

VDR polymorphisms may contribute to susceptibility to AA and influence the severity and prognosis of AA in a Chinese population.