[Research advances on mechanism of exosomes derived from adipose derived stem cells in the treatment of chronic wounds].

Exosomes are a kind of membrane vesicle with a diameter of 30-150 nm. It is formed by the budding of multiple vesicles in cells, which can fuse with the cell membrane and be released into the extracellular matrix. Adipose derived stem cells (ADSCs) have the potential of self-renewal and multi-directional differentiation. They can transport the active substance, regulate the inflammatory response, cell migration, proliferation, differentiation and angiogenesis via the action of paracrine exosomes, so as to enhance the ability of wound repair, promote wound healing, and inhibit the formation of scars. Chronic wounds refer to the wounds that can not reach the anatomic and functional integrity through the normal, orderly, and timely repair process, and the course of the wound healing is more than 4 weeks. At present, there are various treatment methods for chronic wounds, among which ADSCs, although showing a good application prospect, have some limitations due to ethical issues, while exosomes can avoid this problem. This article reviews the treatment of chronic wounds with ADSC exosomes.

[Early debridement combined with antidote in the treatment of one patient with chromic acid burn and acute kidney injury].

On November 16, 2018, one male patient, aged 52 years was admitted to Northern Jiangsu People's Hospital due to thermal chemical burn to the right lower limb for 1 hour. The total burn area reached 9% total body surface area (TBSA), including 7%TBSA of partial-thickness burn and 2% TBSA of full-thickness burn. After admission, the patient was treated with anti-infection, analgesia, fluid infusion. On November 19, the patient developed symptoms such as nausea, vomiting, and oliguria, the related laboratory examination showed acute kidney injury, and the patient was immediately treated with continuous renal replacement therapy. Eschar excision, eschar cutting and shaving, skin grafting were performed on 20 and 27 November, and the specific antidote was applied. After active treatment, the patient's condition was gradually stable and recovered, and he was discharged 2 months later. There was no obvious abnormality during follow-up of 5 months after discharge. This case reminds that clinicians shall strengthen the understanding of chromic acid burns, especially for the patient combined with thermal burns, timely and effective treatment of wounds after burns, close monitoring of liver and kidney function and blood chromium concentration, and early application of antidote are necessary.

MiR-195 promotes myocardial fibrosis in MI rats via targeting TGF-ß1/Smad.

The aim of this study was to investigate the effect of micro ribonucleic acid (miR)-195 on myocardial infarction (MI) in rats via regulating the transforming growth factor-ß1 (TGF-ß1)/Smad signaling pathway. A total of 36 Sprague-Dawley rats were randomly divided into a normal group (n=12), a model group (n=12) and an miR-195 antagomir group (n=12). In the normal group, the heart was exposed only, and normal saline was intraperitoneally injected after operation. In the model group, the acute MI model was established. In the miR-195 antagomir group, the acute MI model was also established, and miR- 195 antagomir was intraperitoneally injected. The samples were collected at 2 weeks after surgery. Then cardiac function was detected via echocardiography, and the morphology of heart tissues was observed via hematoxylin and eosin (H&E) staining. Moreover, the expression of Collagen I was determined using immunohistochemistry, the protein expressions of TGF-ß1, Smad3 and Smad7 were detected using Western blotting, and the expression of miR-195 was detected via quantitative polymerase chain reaction (qPCR). It was found by echocardiography that, compared with those in the normal group, left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) significantly declined, while left ventricular end-diastolic diameter (LVDd) and left ventricular end-systolic diameter (LVDs) significantly rose in the other two groups (P<0.05). In comparison with the model group, the miR-195 antagomir group had significantly increased LVEF and LVFS, and significantly decreased LVDd and LVDs (P<0.05). The immunohistochemistry results showed that the mean optical density of tissues with positively expressed Collagen I was obviously higher in the other two groups than that in the normal group (P<0.05), while it was obviously lower in the miR-195 antagomir group than that in the model group (P<0.05). According to the results of Western blotting, the protein expressions of TGF-ß1 and Smad3 were evidently increased, while the protein expression of Smad7 was evidently decreased in the other two groups compared with those in the normal group (P<0.05). The opposite results were found in the miR-195 antagomir group compared with those in the model group (P<0.05). The results of qPCR manifested that the expression of miR-195 was markedly higher in the other two groups than that in the normal group (P<0.05), while it was markedly lower in the miR-195 antagomir group than in the model group (P<0.05). Moreover, it was observed using H&E staining that the myocardial fibers in the normal group had normal arrangement and intact structure, without obvious morphological abnormalities. In the model group, the myocardial fibers were arranged disorderly, and there were massive proliferating fibrous tissues, with a high degree of fibrosis. In themiR-195 antagomir group, the myocardial fibers were damaged and arranged less disorderly, and proliferation and fibrosis could be seen in some fibrous tissues, but to a lesser extent than the model group. In conclusion, miR-195 promotes myocardial fibrosis in MI rats via up-regulating the TGF-ß1/Smad signaling pathway.

[Meta-analysis of the effects of dexmedetomidine combined with ketamine during dressing changes in burn patients].

Objective: To systematically evaluate the safety and efficacy of dexmedetomidine combined with ketamine during dressing changes in burn patients using meta-analysis. Methods: Foreign language databases including PubMed, Cochrane Central, Embase, and Web of Science were searched with the terms of " burns, dexmedetomidine, ketamine, and dressing" , and Chinese databases including Chinese Journal Full-Text Database, Wanfang Data, and China Academic Journal Network Publishing Database were searched with the terms in Chinese version of ",,,,," to retrieve the publicly published randomized controlled trials on the application of dexmedetomidine combined with ketamine for sedation and analgesia during dressing changes in burn patients from the establishment of each database to March 2019. The outcome indexes included systolic blood pressure at 5 minutes after administration, arousal restlessness score, ketamine dosage, dressing change time, body movement/recovery time, pain score, Ramsay sedation scores at 10 minutes after the start of dressing change and 1 hour after dressing change, physician satisfaction score, neuropsychological symptoms, nausea and vomiting times, nausea and vomiting score. RevMan 5.3 and Stata 14.0 statistical software were used to conduct a meta-analysis of eligible studies. Results: A total of 396 burn patients were included in 7 articles, including 198 patients in dexmedetomidine+ ketamine group who received dexmedetomidine and ketamine for sedation and analgesia, and 198 patients in ketamine alone group who received ketamine alone for sedation and analgesia. The bias risks of the seven studies included were uncertain. Compared with those of ketamine alone group, the systolic blood pressure at 5 minutes after administration, arousal restlessness score, nausea and vomiting score of patients in dexmedetomidine+ ketamine group were significantly decreased, with standardized mean differences of -13.89, -0.84, and -0.99 (95% confidence interval=-20.89--6.89, -1.17--0.52, -1.31--0.68, P<0.01), the Ramsay sedation score at 10 minutes after the start of dressing change and that at 1 hour after dressing change were significantly increased, with standardized mean differences of 1.53 and 0.72 (95% confidence interval=1.05-2.02, 0.13-1.31, P<0.05 or P<0.01), and the number of neuropsychological symptom and number of nausea and vomiting were significantly reduced, with relative risks of 0.20 and 0.16 (95% confidence interval=0.07-0.58, 0.05-0.58, P<0.01). The patients in the two groups were similar in ketamine dosage, dressing change time, body movement/recovery time, pain score, and physician satisfaction score. There was no publication bias in dressing change time or ketamine dosage (P>0.05), while the other indexes might have publication bias (P<0.05). Conclusions: Compared with ketamine alone, combination of dexmedetomidine and ketamine during dressing changes in burn patients can reduce the occurrence of restlessness, nausea and vomiting, neuropsychological symptoms, and other complications, better stabilize blood pressure, and enhance sedation effect.

[Advances in the research of heterotopic ossification caused by burns].

Heterotopic ossification is a rare complication of burns, and its incidence and risk factors are still unclear. Through summarizing the literature on heterotopic ossification caused by burns at home and abroad, the author searched for the risk factors of heterotopic ossification after burn and the new progress of its prevention and treatment. It was realized that the size, depth and healing time of burn wounds were related to heterotopic ossification; the nonsteroidal anti-inflammatory drugs, radiation therapy, and their combination therapy can be used for the prevention of heterotopic ossification; surgery is an effective means of treating heterotopic ossification.

[Current status of malaria rapid diagnostic testing strips application in primary-level healthcare providers in Jiangsu Province].

Objective: To investigate the current status of malaria rapid diagnostic test (RDT) strips application and malaria laboratory technicians' evaluation about them at primary healthcare provider level in Jiangsu Province. Methods: From November to December 2016, 878 medical institutions and 118 CDCs of city, county and township/community level in Jiangsu Province were selected as study samples using stratified random sampling method. Self-designed questionnaire was distributed to investigate the institution's malaria work task, RDT strips application and evaluation status in 2015. We also investigated the socio-demographic information and collected the RDT strips evaluation score from the malaria laboratory technicians selected from the institutions investigated (one technician from each institution). Rank sum test was performed to compare the RDT strips evaluation scores between medical institutions and CDCs, and among different medical institutions and CDCs. Results: In 2015, 405 cases of malaria were reported, 362 200 person-time of malaria blood testing task was conducted, and 100 000 RDT strips were procured and provided for healthcare providers in Jiangsu province for free. Of the 996 healthcare institutions investigated, 628 used RDT strips in the year 2015 and the median (P(25), P(75)) of RDT strips volume used in these institutions was 10 (2, 25). The volume of RDT strips used in CDCs (15 (5, 52)) was significantly higher than that in medical institutions (10 (2, 25), (Z=3.42, P=0.001)). The investigated CDCs gave higher score on RDT strips' testing time per operation (10 (8.5, 10)) than medical institutions (9(8, 10), (Z=-2.20, P=0.028)). The employers of 614 investigated malaria laboratory technicians used RDT strips in 2015. The median of the scores given by CDC malaria laboratory technicians for RDT strips in terms of testing time per operation, testing operation and results judgement difficulties were 10 (9, 10), 10 (9, 10) and 10 (9, 10), respectively, which were significantly higher than those from technicians of medical institutions (9 (8, 10), 9 (8, 10), 9 (8, 10), (Z values were -2.55, -2.97 and -2.96, respectively; P values were all less than 0.05)). Conclusion: RDT strips had been widely performed in health institutions in Jiangsu Province. The amount of RDT strips used in CDCs was significantly higher than that in medical institutions. Primary-level institutions and malaria laboratory technicians generally recognized RDT strips' advantage for application in terms of testing time and operational procedure. CDCs and malaria laboratory technicians from them gave higher regards on RDT strips in terms of testing time per operation, testing operation and results judgement difficulties compared with that of medical institutions.

Protective effect of erythropoietin against lipopolysaccharide induced inflammation and mitochondrial damage in liver.

Recent studies have shown that liver dysfunction is an early event in sepsis. Pre-existing liver dysfunction is a risk factor for progression of infection to sepsis. However, the mechanism of the liver immune response in promoting sepsis and the importance of liver function are not completely understood. In the present study, we investigated the protective effect of erythropoietin (EPO) against mitochondrial dysfunction in a lipopolysaccharide (LPS)-induced sepsis model, and examined the underlying signaling mechanisms. Enzyme linked immunosorbent assay (ELISA) and reactive oxygen species (ROS) analysis were used to evaluate the levels of interleukin (IL)-1ß and ROS. The effects of EPO on hepatic mitochondrial function were studied by detecting the mitochondrial DNA (mtDNA) copy number using real-time PCR (RT-PCR). To explore the mechanism of action of EPO in sepsis, protein expressions of IL-1ß, caspase-1 and NLRP3 were assessed by Western blotting; liver histopathology and ultrastructure of liver mitochondria was examined by transmission electron microscopy. We found that LPS treatment increased serum IL-1ß and ROS levels, the effect of which was attenuated by EPO. Moreover, LPS treatment also increased the mtDNA copy number and the protein expressions of IL-11ß, caspase-1, and NLRP3, which were suppressed by EPO. Histological examination of liver showed LPS-induced cellular edema in hepatic lobules, lymphocytic infiltration and hepatocellular necrosis; these changes were also alleviated by EPO treatment. On electron microscopy, the size of hepatocellular mitochondria in the LPS group was smaller than that in the control group, and the changes were reversed by EPO in the LPS+EPO group. Our results suggest that EPO alleviated liver and mitochondrial damage induced by LPS, possibly via inhibition of NLRP3 signaling.

[Recurrent syncope related to catecholaminergic polymorphic ventricular tachycardia due to de novo RyR2-R2401H mutation].

Objective: To explore the clinical and molecular genetic features of a Chinese patient with catecholaminergic polymorphic ventricular tachycardia (CPVT). Methods: Clinical data including resting electrocardiography, echocardiography and treadmill exercise testing of a patient with CPVT admitted to our department in March 2013 were analyzed, and the peripheral venous blood samples of the patient and his family members and 400 ethnicity-matched healthy controls were obtained. All exons and exon-intron boundaries of the six CPVT-related genes including RYR2, CASQ2, TRDN, CALM1, KCNJ2 and ANKB were sequenced to detect the variants related to CPVT. The relationship between the genotypes and phenotypes was analyzed to direct the target therapy. Results: Recurrent syncope induced either by exercise or extreme frightened fear was observed in this patient. There was no positive family history of syncope or sudden death. The resting electrocardiography and echocardiography of the patient were normal, while the exercise testing revealed bidirectional and polymorphic ventricular tachycardia. A cardiac ryanodine receptor gene mutation (R2401H) was identified in this patient, while this mutation was absent in his parents and sister and 400 controls. No variant was detected in the remaining five candidate genes. Treatment with high dose of metoprolol succinate (118.75 mg/d) was effective and patient was free of syncopal attack during the 2 years follow-up. Conclusion: This is the first report on RyR2-R2401H mutation in Chinese patient with CPVT, and high dose of metoptolol is the effective therapy option for CPVT related to RyR2 mutation.

Analyzing the association between XRCC1 c.1804C>A genetic variant and lung cancer susceptibility in the Chinese population.

Lung cancer is the most common cancer occurring worldwide. The human X-ray repair complementing group 1 (XRCC1) gene is one of the most important candidate genes that influence the susceptibility to lung cancer. The objective of this study was to analyze the potential association between the c.1804C>A genetic variant of XRCC1 and lung cancer susceptibility. A total of 703 subjects were recruited for this study. Genotyping of c.1804C>A genetic variant was performed using the created restriction site-polymerase chain reaction. Statistically significant differences in allele frequencies and genotype were found between lung cancer patients and cancer-free controls. The genotype AA was statistically associated with the increased risk of lung cancer when compared to the wild genotype, CC, and the carrier genotype, CA/CC (AA vs CC: OR = 2.71, 95%CI = 1.57-4.67, P < 0.001; AA vs CA/CC: OR = 2.54, 95%CI = 1.50-4.29, P < 0.001). The allele A likely contributes to the susceptibility to lung cancer (A vs C: OR = 1.47, 95%CI = 1.17-1.84, P = 0.001). Our data indicates that the c.1804C>A genetic variant of XRCC1 is statistically associated with the susceptibility to lung cancer in the Chinese population.

Chronopharmacology of analgesic effect and tolerance induced by six narcotic analgesics in mice.

Narcotic analgesics, especially morphine, exert significantly different effects depending on the time within one day. The objective of this study was to observe whether the dosing time of 6 narcotic analgesics in mice affected their efficacy, pain tolerance and recovery of tolerance. The chronopharmacology of these 6 narcotics was evaluated using a hot-plate model. Maximum possible effect (MPE) of morphine showed a significant 24 h rhythm, which was higher during the dark phase and lower during the light phase (P<0.05). Conversely, MPEs of fentanyl and bucinnazine groups during the light phase exceeded those during the dark phase (P<0.05). Pain tolerance developed after drug administration at 9:00 am or 9:00 pm for 5 days, of which bucinnazine produced lower tolerance at 9:00 am. After a 2-day washout period, the mice rapidly recovered from tolerance at 3:00 pm for 5-day morphine dosing at 9:00 pm, and for fentanyl dosing at 9:00 am. Not all narcotic analgesics displayed significant circadian variations, and the dosing time-dependent effects also depended on the types of narcotics. Therefore, the time of administration is crucial in clinical pain treatment. Chronotherapy may be more effective to relieve pain while reducing side effects.

The effect of horse simulator riding on visual analogue scale, body composition and trunk strength in the patients with chronic low back pain.

BACKGROUND: Chronic low back pain (CLBP) is one of the most common musculoskeletal disorders, and thus effective treatments are required. Recently, real horseback riding has been reported to be beneficial for the patients. However, it has some limitations, such as limited approaches and safety issues. OBJECTIVE: The purpose of this study was to investigate the effect of horse simulator riding on back pain, body composition and trunk strength in the patients with CLBP. PARTICIPANTS: Forty-seven men with CLBP (mean age 20.55 ± 1.38 years) were randomly divided into a control group (n = 23) and a horse simulator riding group (n = 24), and visual analogue scale (VAS), body composition and isokinetic trunk strength were measured after 8 weeks for which subjects in a horse simulator riding group had performed the horse simulator exercise (HSE). RESULTS: Horse simulator exercise significantly reduced pain scores of VAS and enhanced isokinetic torques of trunk at 30 and 90°/s. There were also significantly increased muscle mass and decreased fat mass in horse simulator riding group. CONCLUSION: It can be inferred that HSE may be helpful in relief of back pain and recovery of back function through developing trunk strength and balancing the ratio of trunk flexor/extensor muscles.

[Study of sesquiterpene alkaloids from Tripterygium wilfordii Hook.f].

AIM: To study the chemical composition of Tripterygium wilfordii Hook.f. METHODS: Column chromatography was used to separate the chemical constituents. UV, IR, MS, HRMS, 1HNMR, 13CNMR (COM and OFR), 1H-1H COSY, 1H-13C COSY, 2D-NOESY and 1H-13C COLOC were used to determine the structures of the isolated constituents. RESULTS: Two sesquiterpene alkaloids were isolated and their structures were elucidated as euonine and wilfordconine on the basis of spectral evidence. CONCLUSION: Wilfordconine, a new sesquiterpene alkaloid, was shown to be immunosuppressive.

Wild type neu transgene counteracts mutant homologue in malignant transformation of rat Schwann cells.

Mutational activation of the neu (erbB-2) receptor protein tyrosine kinase gene appears to be the triggering event in the process of oncogenesis induced by N-ethyl-N-nitrosourea (EtNU) in immature Schwann cells of the rat peripheral nervous system. Subsequent loss of the wild-type neu allele may represent a critical secondary step towards malignancy. Developmentally-regulated expression of a wild-type rat neu transgene (neu cDNA under the control of the rat Po promoter) in the Schwann cells of transgenic BDIX and Sprague-Dawley rats exposed to EtNU on postnatal day 1 results in a lower incidence of early atypical proliferates in the trigeminal nerve. Furthermore, re-introduction of the wild-type neu gene into homozygous neu mutant schwannoma cells counteracts the expression of the tumorigenic phenotype. The suppressive action of the wild-type gene over its mutationally activated oncogenic homologue underlines the critical function of the neu gene in the control of differentiation in the Schwann cell lineage, and provides evidence for the responsiveness of cellular phenotypes towards quantitative shifts in the dosage of wild-type vs mutant signal transducing molecules.

[Anti-inflammatory effect of Caragana microphylla Lam].

Caragana microphylla can antagonize the inflammation induced by carrageenin, hot water and croton oil. It can also inhibit the proliferation of granuloma, blood capillary permeability, phagocytic function of mononuclear phagocyte system, and synthesis or release of PGE2 at the inflamed part.

Schwann cell lineage-specific neu (erbB-2) gene expression in the developing rat nervous system.

Initiation of oncogenesis in the immature peripheral nervous system (PNS) of rats by the DNA-reactive carcinogen N-ethyl-N-nitrosourea (EtNU) involves a specific T:A-->A:T transversion mutation at nucleotide 2012 of the neu (erbB-2) receptor tyrosine kinase gene in cells of the Schwann cell lineage. Although this mutation is invariably detected in the resulting malignant schwannomas, it is not found in EtNU-induced tumors of the central nervous system (CNS). We have evaluated expression of the neu gene in the PNS and CNS as a function of developmental stage. Cellular levels of neu mRNA and gp185neu were analyzed in the trigeminal and sciatic nerve and in brain, using a quantitative reverse transcription-polymerase chain reaction, in situ hybridization, immunocytochemistry, and fluorescence-activated cell sorting. In the PNS, expression of the neu gene is restricted to cells of the Schwann cell lineage and markedly exceeds expression in the CNS from prenatal day 20 onward. In trigeminal Schwann cells, neu mRNA is most abundant (2.8 x 10(7) copies/micrograms of RNA) on postnatal day 1, coincident with both the end of maximum mitotic activity and the "developmental window" of highest sensitivity to malignant transformation by EtNU. The subsequent decrease of neu gene expression is accompanied by decreasing proliferative activity and the onset of myelination. The level of neu gene expression may thus be critical to proliferation versus differentiation decisions in the Schwann cell lineage. EtNU-induced mutation of the neu gene in proliferative Schwann cell precursors expressing gp185neu may abrogate their responsiveness to extracellular and/or intrinsic controls, resulting in sustained proliferative activity and malignant conversion.

[Effect of expression of exogenous PDGF-A chain on growth and transformation of CHO cells].

CHO cells were transfected with plasmid pSV2-PDGF-A (containing human PDGF-A cDNA) by calcium phosphate method. Twenty transfected cell lines were obtained after G418 selection. The selected 2 cell lines At1 and Aot7), with prominent changes in morphology and growth behaviour, showed transcription of PDGF-A chain mRNA much higher than CHO cells, strong fluorescent PDGF-specific reaction, appearing that PDGF-like proteins were synthesized in cytoplasm of these cells. At1 and Aot7 cells not only had increased growth rate, but also formed large colonies in soft agar and grew into fibrosarcomas in nude mice. These results suggested that the expression of exogenous PDGF-A gene might cause the uncontrolled growth and malignant transformation of CHO cells.

[Expression of exogenous platelet-derived growth factor B chain gene in CHO cells].

CHO cells were transfected with plasmid pSM-1 (containing human c-sis cDNA) singly or co-transfected with pSV 2 neo DNA by calcium phosphate method. After low serum or G418 selection several cell lines with expression of platelet-derived growth factor (PDGF) were obtained. One among them, FB5, was of the highest PDGF expression and showed the following biological characteristics when compared with CHO cells: (1) a prominent change in morphology from spindle to round in shape: (2) increase of growth rate; (3) growth in low serum (2%) medium as a semisuspension culture; (4) growth on soft agar to larger colonies; (5) synthesis of PDGF in cytoplasm identified by immunofluorescent method; (6) the conditioned medium stimulated DNA synthesis of NRK cells; (7) RNA dot hybridization showing high transcription of PDGF mRNA; (8) southern blot showing integration of human c-sis gene was still stable after 7 months. These results indicated that intergration of exogenous c-sis gene and its high expression might cause CHO cells to high growth rate and even transformation. The establishment of this stable transformed cell line, FB5 is thought to be a good model for further study on the function of PDGF in cell growth control and cell transformation.