Crosslinking strategies of decellularized extracellular matrix in tissue regeneration.

By removing the immunogenic cellular components through various decellularization methods, decellularized extracellular matrix (dECM) is considered a promising material in the field of tissue engineering and regenerative medicine with highly preserved physicochemical properties and superior biocompatibility. However, decellularization treatment can lead to some loss of structural integrity, mechanical strength, degradation stability, and biological performance of dECM biomaterials. Therefore, physical and chemical crosslinking methods are preferred to restore or even improve the biomechanical properties, stability, and bioactivity, and to achieve a delicate balance between degradation of the implanted biomaterial and regeneration of the host tissue. This review provides an overview of dECM biomaterials, and describes and compares the mechanisms and characteristics of commonly used crosslinking methods for dECM, with a focus on the potential applications of versatile dECM-based biomaterials derived from skin, cardiac tissues (pericardium, heart valves, myocardial tissue), blood vessels, liver, and kidney, modified with different chemical crosslinking reagents, in tissue and organ regeneration.

Identification of Plasma Biomarkers in Drug-Naïve Schizophrenia Using Targeted Metabolomics

Objective@#Schizophrenia (SCZ) is a severe psychiatric disorder with unknown etiology and lacking specific biomarkers. Herein, we aimed to explore plasma biomarkers relevant to SCZ using targeted metabolomics. @*Methods@#Sixty drug-naïve SCZ patients and 36 healthy controls were recruited. Psychotic symptoms were assessed using the Positive and Negative Syndrome Scale. We analyzed the levels of 271 metabolites in plasma samples from all subjects using targeted metabolomics, and identified metabolites that differed significantly between the two groups. Then we evaluated the diagnostic power of the metabolites based on receiver operating characteristic curves, and explored metabolites associated with the psychotic symptoms in SCZ patients. @*Results@#Twenty-six metabolites showed significant differences between SCZ patients and healthy controls. Among them, 12 metabolites were phosphatidylcholines and cortisol, ceramide (d18:1/22:0), acetylcarnitine, and γ-aminobutyric acid, which could significantly distinguish SCZ from healthy controls with the area under the curve (AUC) above 0.7. Further, a panel consisting of the above 4 metabolites had an excellent performance with an AUC of 0.867. In SCZ patients, phosphatidylcholines were positively related with positive symptoms, and cholic acid was positively associated with negative symptoms. @*Conclusion@#Our study provides insights into the metabolite alterations associated with SCZ and potential biomarkers for its diagnosis and symptom severity assessment.

Apolipoprotein E ε4 Polymorphism as a Risk Factor for Ischemic Stroke: A Systematic Review and Meta-Analysis.

INTRODUCTION: Rising studies indicate that the apolipoprotein E (APOE) gene is related to the susceptibility of ischemic stroke (IS). However, certain consensus is limited by the lack of a large sample size of researches. This meta-analysis was performed to explore the potential association between the APOE gene and IS. METHODS: To identify relevant case control studies in English publications by October 2020, we searched PubMed, Embase, Web of Science, and the Cochrane Library. Pooled odds ratios (ORs) with fixed- or random-effect models and corresponding 95% confidence intervals (CIs) were calculated to analyze potential associations. RESULTS: A total of 55 researches from 32 countries containing 12207 IS cases and 27742 controls were included. The association between APOE gene ε4 mutation and IS was confirmed (ε4 vs. ε3 allele: pooled OR = 1.374, 95% CI, 1.214-1.556; ε2/ε4 vs. ε3/ε3: pooled OR = 1.233, 95% CI, 1.056-1.440; ε3/ε4 vs. ε3/ε3: pooled OR = 1.340, 95% CI, 1.165-1.542; ε4/ε4 vs. ε3/ε3: pooled OR = 1.833, 95% CI, 1.542-2.179; and APOE ε4 carriers vs. non-ε4 carriers: pooled OR = 1.377; 95% CI, 1.203-1.576). Interestingly, APOE ε4 mutation showed a dose-response correlation with IS risk (ε4/ε4 vs. ε2/ε4: pooled OR = 1.625; 95% CI, 1.281-2.060; ε4/ε4 vs. ε3/ε4: pooled OR = 1.301; 95% CI, 1.077-1.571). Similar conclusions were drawn in the small artery disease (SAD) subtype, but not in large artery atherosclerosis (LAA) or in cardioaortic embolism (CE), by subgroup analysis. CONCLUSIONS: These observations reveal that specific APOE ε4 mutation was significantly associated with the risk of IS in a dose-dependent manner, while APOE ε4 mutation was related to SAD subtype onset without a cumulative effect.

Dynamic changes of peripheral blood lymphocyte subsets in acute ischemic stroke and prognostic value.

OBJECTIVE: To explore dynamic changes of peripheral blood lymphocyte subsets in patients with acute ischemic stroke (AIS) and the relationship with stroke severity and long-term outcomes. METHODS: A total of 96 consecutive patients with AIS and 28 age- and gender-matched healthy controls were recruited. Peripheral blood samples were collected, and the percentages of lymphocyte subsets were analyzed by flow cytometry. The dynamic changes in lymphocyte subsets and their correlation with clinical parameters, such as National Institutes of Health Stroke Scale (NIHSS) scores at onset and modified Rankin scale (mRS) scores 3 months later, were evaluated. RESULTS: In our study, we observed a decrease in the percentages of T-lymphocytes (T cells), helper/inducible T-lymphocytes (Th cells) and suppressor/cytotoxic T-lymphocytes (Ts cells) in AIS patients as compared to controls. The frequencies of T cells and Ts cells on day 8-14 after stroke in NIHSS ≤4 group were significantly higher than those in NIHSS >4 group. The percentages of T cells and Th cells on day 1-3 after stroke in the mRS ≤2 group were higher than those in the mRS >2 group. CONCLUSION: The frequencies of T cells, Th cells, and Ts cells in AIS are declined dramatically at least 14 days after stroke. Lower frequencies of T cells and Ts cells on day 8-14 after stroke represent more severe disease conditions, and the percentages of T cells and Th cells within 72 hr after stroke are negatively correlated with 3-month outcomes, which might have a potential for predicting long-term prognosis of stroke.

Low expression of CDK12 in gastric cancer is correlated with advanced stage and poor outcome.

BACKGROUND: Cyclin-dependent kinase 12 (CDK12) belongs to the cyclin-dependent kinase (CDK) family, modulating multiple cellular functions including DNA damage response (DDR), development and cellular differentiation, transcription, mRNA processing, splicing and pre-mRNA processing. CDK12 has been reported as both tumor suppressor and oncogene in various kinds of tumor. The function of CDK12 in gastric cancer (GC) remains unclear. METHODS/RESULTS: CDK12 mRNA expression was decreased in GC compared with non-tumor tissue based on GEO database. Also, low mRNA expression of CDK12 was detected in GC cell lines by qPCR. Similarly, CDK12 protein expression was also reduced in GC tissues compared with adjacent non-tumor tissues in 177 GC patients as shown by immunohistochemistry. Low expression of CDK12 was associated with organ metastasis, poorly differentiated adenocarcinoma and advanced stage. Consistent with human protein atlas database analysis, Low expression of CDK12 was correlated with worse overall survival (P < 0.001). Multivariate Cox regression indicated that low expression of CDK12 was an independent prognostic factor for GC patients (P < 0.001). Finally, a gene set enrichment analysis was performed to detect underlying internal mechanisms and biological processes. CONCLUSIONS: CDK12 is down-regulated in GC and its expression is negatively correlated with advanced stage, poorly differentiated adenocarcinoma and poor outcomes. Our findings suggest that CDK12 may be a potential tumor suppressor in GC.

Study on chemical constituents of Dendrobium huoshanense stems and their anti-inflammatory activity / 中国中药杂志

Three bibenzyls 1-3 and six other compounds 4-9 were firstly isolated from Dendrobium huoshanense stems. They were identified as 3',4-dihydroxy-3,5'-dimethoxybibenzyl(1), batatasin Ⅲ(2), 3,4'-dihydroxy-5-methoxy bibenzyl(3), dihydroconiferyl dihydro-p-coumarate(4), syringaresinol(5), 3-(4-hydroxyphenyl)-propionic acid ethyl ester(6),(3-ethylphenyl)-1,2-ethanediol(7),(S)-5-hydroxy-3,4-dimethyl-5-pentylfuran-2(5H)-one(8) and loliolide(9). Anti-inflammation assay showed that bibenzyls 1-3 could significantly inhibit the production of nitric oxide(NO) and the expression of tumor necrosis factor α(TNF-α) and interleukin 1β(IL-1β) mRNA in LPS-induced RAW264.7 macrophages. Mechanism study exhibited that the phosphorylation of nuclear factor kappa B(NF-κB) p65, inhibitor of κB(IκB), extracellular regulatedprotein kinase(ERK), c-Jun N-terminalkinase(JNK), p38 and Akt of LPS-induced RAW264.7 macrophages could be remarkably reduced by 1. These results suggested that the inflammatory response of LPS-induced RAW264.7 macrophages could be significantly inhibited by 1-3. Additionally, the anti-inflammatory effect of 1 might be contributed to its ability on the regulation of NF-κB, MAPKs and Akt signaling pathways.

Establishment of a non-venous bypass orthotopic liver transplantation model in Bama miniature pigs / 器官移植

Objective To establish a non-venous bypass orthotopic liver transplantation model in Bama miniature pigs with high repeatability and stability. Methods Twelve Bama miniature pigs were randomly divided into the donor group (n=6) and recipient group (n=6). Pigs underwent non-venous bypass orthotopic liver transplantation. The time of anhepatic phase during operation was shortened, blood pressure during anhepatic phase was stably maintained, and management of anesthesia and body fluid during operation were strengthened. The operation time, anhepatic phase and survival status of the recipients were observed and recorded. The intraoperative heart rate, mean arterial pressure (MAP) and changes in arterial blood gas analysis were monitored. The perioperative liver function was evaluated. Results Among 6 Bama miniature pigs, 1 died from transplantation failure intraoperatively. The operation time of the remaining 5 pigs was (247±27) min and the time of anhepatic phase was (46±4) min. Three animals survived for more than 2 weeks. Compared with the preanhepatic phase, the heart rate of the animals was significantly faster, MAP was considerably reduced to (46±6) mmHg, blood pH value, base excess (BE) and HCO3- level were all significantly decreased and serum level of K+ was significantly elevated during the anhepatic phase (all P < 0.05). In the neohepatic phase, MAP of Bama miniature pigs was significantly increased, heart rate was dramatically slower.Blood pH value, BE, HCO3- level were significantly increased and serum level of K+ was significantly declined (all P < 0.05). During abdominal closure, MAP, blood gas indexes and serum level of K+ were almost recovered to those in the preanhepatic phase. Compared with preoperative levels, the levels of alanine aminotransferase(ALT), aspartate aminotransferase(AST), lactate dehydrogenase(LDH)and alkaline phosphatase(ALP)were significantly increased after operation (all P < 0.05), the change in AST was the most obvious, and it gradually decreased at postoperative 2 d. The level of γ-gutamyl transferase(GGT) did not significantly elevated. The level of total bilirubin (TB) was evidently elevated at postoperative 5 d. Compared with the preoperative levels, the levels of total protein (TP) and albumin (ALB) were significantly decreased after operation (both P < 0.05), and began to gradually increase at postoperative 1 d. Conclusions The non-venous bypass orthotopic liver transplantation model of Bama miniature pig is convenient, with highly reproducible and survival rate, which can be utilized as a standardized liver transplantation model.

Establishment of experimental model for saphenous artery perforator flap in mini pig / 中华显微外科杂志

Objective To investigate the anatomy characteristics of saphenous artery(SA) and its perforator vessels in mini pig,and to provide a new perforator flap animal model.Methods Between May,2018 and August,2018,6 7-months-old mini pigs weight 25 kilograms were sacrificed by blooding under general anesthesia.The bilateral external iliac arteries were injected with a mixture of latex-lead oxide mixture and underwent CT-scanning to provide 3-dimensional reconstruction.The origin,diameter,courses and distribution of the SA and perforators of both hind limbs were observed.Results One of the hind limbs was abandoned due to the leakage of perfusion fluid.The other 11 hind limbs were available.The femoral artery passed through the medial femoral muscle and sartorius muscle in the middle of thigh,and run between the medial femoral muscle and gracilis muscle above the knee.Below the knee,it run on the surface of the medial leg muscles.A number of small branches were distributed in the tarsal joint and calcaneus at the medial malleolus,and there were abundant communicating branches with the posterior tibial artery.The average length of SA was (14.86±0.76) mm.The outer diameters of SA at initiative,medial tibial condyle and medial malleolus were(1.73±0.15) mm,(1.50±0.12) mm and (1.30±0.13) mm,respectively.There were a total of 79 perforators which were identified,with a mean of (7.09±1.16) perforators per hind limbs.And the average outer diameter was 0.10-0.78 (0.40±0.13) mm.Conclusion The SA constantly exist with good outer diameter.The number of perforator is abundant.SA can be used as a reliable animal model for studying and training of perforator flap.

Correlation between SHBG gene polymorphism and male infertility in Han population of Henan province of China: A STROBE-compliant article.

Human sex hormone binding globulin (SHBG) level alteration and SHBG gene mutations, especially in rs6259 and rs727428 loci, are associated with male infertility. In this study, the rs6259 and rs727428 loci in SHBG gene were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to explore the direct relation between these 2 loci and male infertility in Han population of Henan province and to provide information for the pathogenesis, diagnosis, and treatment of male infertility.A total of 366 male Han individuals in Henan province were enrolled in this study. Of the 366 male individuals, 183 infertility patients were served as infertility group and other 183 normal individuals as a control group. SHBG gene rs6259 and rs727428 locus polymorphisms were detected by PCR-RFLP in all patients. Also, genotype frequencies, allele frequency, and haplotype were all analyzed in both groups.There were statistical differences in A allele frequency (P = .017) and GA genotype frequency (P = .016) of SHBG gene rs6259 locus and in CC genotype frequency of SHBG gene rs727428 locus (P = .034) between the 2 groups.Male infertility is associated with GA genotype and A allele of rs6259 locus, as well as CC genotype of rs727428 locus in SHBG gene.

Feasibility study on monitoring blood pressure of the superficial temporal artery in neonates / 中华护理杂志

Objective To explore the feasibility of monitoring blood pressure via superficial temporal artery catheterization in neonates,which may provide more ways to monitor arterial blood pressure of neonates.Methods By lottery method,64 neonates from NICU who met inclusion criteria and needed arterial blood pressure monitoring were randomly divided into two groups.Thirty-two cases in the experimental group were treated with superficial temporal artery catheterization,while 32 cases in the control group were treated with radial artery catheterization.The success rate of one-time catheterization,indwelling time of catheter,blood pressure and the rate of complications were compared between two groups.Results There were no significant differences between two groups in the success rate of one-time catheterization,indwelling time of catheter,systolic blood pressure and the rate of complications (P＞0.05).Results showed there was significant difference in diastolic blood pressure between two groups(P＜ 0.05).Conclusion Compared with radial artery blood catheterization,neonatal superficial temporal artery catheterization showed equivalent effect,which made it more convenient for observing condition of neonates.

Feasibility study on monitoring blood pressure of the superficial temporal artery in neonates / 中华护理杂志

Objective To explore the feasibility of monitoring blood pressure via superficial temporal artery catheterization in neonates,which may provide more ways to monitor arterial blood pressure of neonates.Methods By lottery method,64 neonates from NICU who met inclusion criteria and needed arterial blood pressure monitoring were randomly divided into two groups.Thirty-two cases in the experimental group were treated with superficial temporal artery catheterization,while 32 cases in the control group were treated with radial artery catheterization.The success rate of one-time catheterization,indwelling time of catheter,blood pressure and the rate of complications were compared between two groups.Results There were no significant differences between two groups in the success rate of one-time catheterization,indwelling time of catheter,systolic blood pressure and the rate of complications (P＞0.05).Results showed there was significant difference in diastolic blood pressure between two groups(P＜ 0.05).Conclusion Compared with radial artery blood catheterization,neonatal superficial temporal artery catheterization showed equivalent effect,which made it more convenient for observing condition of neonates.

MicroRNA-150 upregulation reduces osteosarcoma cell invasion and metastasis by downregulating Ezrin.

The present study aimed to investigate the effect of microRNA-150 (miRNA/miR-150) in osteosarcoma (OS) cell invasion and metastasis by the regulation of Ezrin. To compare the differences in the expression of miR-150 and Ezrin, cell models of OS metastasis were established by exogenous transfection of miR-150 on the basis of different expression levels of miR-150. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to estimate these expression levels. Ezrin expression was detected by western blot assay. Methylthiazolyldiphenyl-tetrazolium bromide assay was performed to determine cells proliferation. Cell invasion and migration were measured in vitro by Transwell migration assays. Detection of apoptosis adopted flow cytometry. The results of RT-qPCR showed that the miR-150 expression in OS F5M2 cells was significantly increased following exogenous transfection of miR-150 mimics, and the expression of miR-150 was positively correlated with the concentration of the miR-150 mimics. Western blot assay indicated that the Ezrin expression in the F5M2 cells was decreased with the exogenous overexpression of miR-150. Additionally, Transwell assays revealed that the overexpression of miR-150 significantly suppressed the invasion and metastasis ability of the F5M2 cells. miR-150 upregulation may reduce OS cell invasion and metastasis by downregulating the expression of Ezrin.

Rapid birth-and-death evolution of imprinted snoRNAs in the Prader-Willi syndrome locus: implications for neural development in Euarchontoglires.

Imprinted small nucleolar RNAs (snoRNAs) are only found in eutherian genomes and closely related to brain functions. A complex human neurological disease, Prader-Willi syndrome (PWS), is primarily attributed to the deletion of imprinted snoRNAs in chromosome 15q11-q13. Here we investigated the snoRNA repertoires in the PWS locus of 12 mammalian genomes and their evolution processes. A total of 613 imprinted snoRNAs were identified in the PWS homologous loci and the gene number was highly variable across lineages, with a peak in Euarchontoglires. Lineage-specific gene gain and loss events account for most extant genes of the HBII-52 (SNORD115) and the HBII-85 (SNORD116) gene family, and remarkable high gene-birth rates were observed in the primates and the rodents. Meanwhile, rapid sequence substitution occurred only in imprinted snoRNA genes, rather than their flanking sequences or the protein-coding genes located in the same imprinted locus. Strong selective constraints on the functional elements of these imprinted snoRNAs further suggest that they are subjected to birth-and-death evolution. Our data suggest that the regulatory role of HBII-52 on 5-HT2CR pre-mRNA might originate in the Euarchontoglires through adaptive process. We propose that the rapid evolution of PWS-related imprinted snoRNAs has contributed to the neural development of Euarchontoglires.

[Study on the status and related socio-psychological factors of maternal depression among high-risk pregnancy women in Harbin city].

OBJECTIVE: This study aimed to investigate the depression status among high-risk pregnancy women, and to analyze its relevant social and psychological factors. METHODS: A total of 42 high-risk pregnancy women and 40 normal pregnancy women in a teaching hospital in Harbin city were followed up at time points of 32 - 36 weeks pregnancy, one week before labor, one week postpartum, and six weeks postpartum, respectively. During follow-up, the basic situation, social psychosocial factors of pregnancy women were collected and the depression of pregnancy women was measured by self-designed questionnaire and self-rating depression scale. The Edinburgh Postnatal Depression Scale (EPDS) was applied at timepoint of one week postpartum. Single factor analysis and the unconditional multivariate logistic regression were applied for analyzing the on the related social-psychosocial factors among high-risk pregnancy women. RESULTS: The age of high-risk pregnancy women was (31.0±5.6), and the age of normal pregnancy women was (30.5±3.8) (t=0.169, P>0.05). The results showed that the depression rate in high-risk pregnancy women was 45.2% (19/42), which was 25.0% (10/40) in normal pregnancy women, the difference was significant (χ2=3.671, P=0.045). The depression rates at different time points were 30.9% (13/42), 42.9% (18/42), 23.8% (10/42), 26.2% (11/42) in high-risk pregnancy women respectively, and 25.0% (10/40), 15.0% (6/40), 20.0% (8/40), 17.5% (7/40) in the control group respectively, the difference of the depression rates among groups at one week before labor was significant (χ2=7.680, P<0.01), the difference among groups at 32-36 weeks pregnancy (χ2=0.133, P=0.80), at one week postpartum (χ2=0.174, P=0.79) and at six weeks postpartum (χ2=0.903, P=0.43) were not significant. At one week postpartum and six weeks postpartum periods, the EPDS depression rate were 12.5% (4/32), 30.4% (7/23) in case group respectively, 8.3% (3/36), 22.9% (8/35) in control group respectively, the difference were not significant (χ2=0.319, 0.416, P=0.573, 0.519). There were significantly associations between the depression mood of one week before labor and the depressive symptoms of six weeks postpartum in both groups (r=0.824, 0.677, both P values were <0.05). The risk factors for maternal depression among high-risk pregnancy women were not ready for production (OR=2.73, P<0.01) and fearing of childbirth safety (OR=2.89, P<0.01). CONCLUSION: The depression date of high-risk pregnancy was high, especially at the time point one week before labor. Risk factors of maternal depression among high-risk pregnancy were "not ready for production" and "fear of childbirth safety".

Isolation and Transient Expression Assay of PEAMT Gene Promoter from Salicornia europaea / 中国生物工程杂志

Phosphoethanolamine N-methyltransferase (PEAMT) is a key enzyme that catalyzes the synthesis of phosphocholine, which is an important precursor of phosphatidylcholine and glycine betaine. A 1249bp 5'-flanking region of phosphoethanolamine N-methyltransferase gene was isolated by anchored PCR, based on the cDNA sequence of PEAMT from halophyte Salicornia europaea. The transcription start site was identified as A and localized at 301bp upstream of the ATG according to the results of RLM-RACE. In SePEAMT promoter region, many potential cis-acting elements were predicted by PlantCARE and PLACE programs. Aside from the basal transcriptional elements TATA-box and CAAT-box, some stress-responsive motifs such as ABRE, HSE and LTR were found. In addition, some pollen-specific activation-related elements were also present in this region. Binary expression vector was constructed by fusing SePEAMT promoter with GUS gene and designated as pPro. The pPro was transferred into tobacco by Agrobacterium-medicated transformation and transient GUS expression analysis indicated that SePEAMT promoter could drive strong GUS expression.

Screening of Phytase-producing Strain and Cloning of Phytase Gene from the Selected Strain / 微生物学通报

A strain with relative higher phytase-producing ability, Aspergillus fumigatus WY-2 was screened from soil. The optimal pH and temperature for activity of the phytase from A.fumigatus WY-2 were 5.5 and 55 ℃, respectively. The gene encoding the phytase was amplified from genomic DNA of the strain by PCR, and a 1.5 kb DNA fragment was obtained and then was cloned into vector pMD18-T. The sequencing analysis revealed that the DNA fragment contained a whole open reading frame (ORF) of phytase gene. The phytase gene was 1459 bp in length included with a 61 bp intron and encoded 465 amino acids. A signal peptide encoding 26 amino acids was found at 5′end of the gene. There were 7 potential glycosylation sites in the phytase. The present phytase showed 91% identity in nucleotide sequence and 91% identity in deduced amino acids sequence to the previously reported A.fumigatus ATCC34625 phytase.