Wheat miR9678 Affects Seed Germination by Generating Phased siRNAs and Modulating Abscisic Acid/Gibberellin Signaling.

Seed germination is important for grain yield and quality and rapid, near-simultaneous germination helps in cultivation; however, cultivars that germinate too readily can undergo preharvest sprouting (PHS), which causes substantial losses in areas that tend to get rain around harvest time. Moreover, our knowledge of mechanisms regulating seed germination in wheat (Triticum aestivum) remains limited. In this study, we analyzed function of a wheat-specific microRNA 9678 (miR9678), which is specifically expressed in the scutellum of developing and germinating seeds. Overexpression of miR9678 delayed germination and improved resistance to PHS in wheat through reducing bioactive gibberellin (GA) levels; miR9678 silencing enhanced germination rates. We provide evidence that miR9678 targets a long noncoding RNA (WSGAR) and triggers the generation of phased small interfering RNAs that play a role in the delay of seed germination. Finally, we found that abscisic acid (ABA) signaling proteins bind the promoter of miR9678 precursor and activate its expression, indicating that miR9678 affects germination by modulating the GA/ABA signaling.

Identification of a potential neutralizing linear epitope of hemagglutinin-neuraminidase in Newcastle disease virus.

BACKGROUND: The hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) is a major antigen that can induce protective antibodies in poultry. However, its antigenic epitopes have not been fully elucidated. Therefore, defining the linear epitopes of HN, especially neutralizing epitopes, will be useful for revealing its antigenic characterization. METHODS: In this study, we analyzed B-cell immunodominant epitopes (IDEs) of the HN protein from the vaccine strain LaSota using pepscan technology with LaSota-specific chicken hyperimmune antisera. We constructed IDEs-RFP plasmids and prepared anti-IDEs peptide mouse sera to identify IDEs through immunological tests. At last, the different diluted anti-IDE antisera were used in BHK-21 cells to perform the neutralization test. RESULTS: Five IDEs of the HN were screened and further verified by indirect immunofluorescence assays, dot blots and Western blots with NDV- and IDEs-specific antisera. All five IDEs showed good immunogenicity. IDE5 (328-342 aa) could recognize only class II NDV but did not react with the class I strain. Most of the IDEs are highly conserved among the different strains. A neutralization test in vitro showed that the peptide-specific mouse antisera of IDE4 (242-256 aa) and HN341-355, a reported neutralizing linear epitope, could partially neutralize avirulent LaSota as well as virulent strains at similar levels, suggesting that IDE4 might be a potential neutralizing linear epitope. CONCLUSION: The HN protein is a major protective antigen of NDV that can induce neutralizing antibodies in animals. We identified five IDEs of the HN using a pepscan approach with NDV-specific chicken hyperimmune antisera. The five IDEs could elicit specific antibodies in mice. IDE4 (242-256 aa) was identified as a novel potential neutralizing linear epitope. These results will help elucidate the antigenic epitopes of the HN and facilitate the development of NDV vaccines.

Failure Risk of Short Dental Implants Under Immediate Loading: A Meta-Analysis.

PURPOSE: Currently, there is no clear clinical evidence that short implants are suitable for immediate loading. Therefore, this meta-analysis aims to evaluate whether immediate loading increases the failure risk of short dental implants. MATERIALS AND METHODS: This meta-analysis was registered at PROSPERO (CRD 42020195890). PubMed, Embase, and Cochrane Library databases were searched to collect all clinical studies comparing the failure rates of short dental implants (<10 mm) and standard implants (≥10 mm) under the condition of immediate loading and studies comparing the failure rates of short dental implants under immediate loading versus early or delayed loading. All of the clinical studies with available relevant data were eligible for inclusion. The Cochrane Risk of Bias tool was adopted to evaluate the risk of bias for the randomized controlled trial (RCT), while Newcastle-Ottawa Quality Assessment Scale (NOS) was used for the observational studies (OS). The OR value of each included study and its 95% CI were pooled to estimate the failure risk of short dental implants under immediate loading. The heterogeneity among studies was evaluated through Cochran's Q test and I2 . RESULTS: Seventeen studies, 5 RCTs and 12 OS studies, with a total of 2461 dental implants were analyzed. Four of the RCT studies were of low risk of bias and one was of unclear risk, while all of the OS studies were of moderate or high quality. Compared with standard implants, short implants did not have an increased failure risk under immediate loading (OR: 1.38, 95% CI: 0.67-2.84, p = 0.997, fixed model). In addition, the OR value of implant failure for short implants under immediate loading compared to that for short implants under early or delayed loading was 1.22 (95% CI: 0.33-4.55, p = 0.104, random model), which was also not significantly different. CONCLUSIONS: There is not enough evidence to show that short dental implants under immediate loading may have higher implant failure risk compared to standard implants under immediate loading and short implants under early or delayed loading. Therefore, an immediate loading protocol may not increase the failure risk of short dental implants.

Host CARD11 Inhibits Newcastle Disease Virus Replication by Suppressing Viral Polymerase Activity in Neurons.

Host factors play multiple essential roles in the replication and pathogenesis of mammalian neurotropic viruses. However, the cellular proteins of the central nervous system (CNS) involved in avian neurotropic virus infection have not been completely elucidated. Here, we employed a gene microarray to identify caspase recruitment domain-containing protein 11 (CARD11), a lymphoma-associated scaffold protein presenting brain-specific upregulated expression in a virulent neurotropic Newcastle disease virus (NDV)-infected natural host. Chicken primary neuronal cells infected with NDV appeared slightly syncytial and died quickly. CARD11 overexpression inhibited viral replication and delayed cytopathic effects; conversely, depletion of CARD11 enhanced viral replication and cytopathic effects in chicken primary neuronal cells. The inhibition of viral replication by CARD11 could not be blocked with CARD11-Bcl10-MALT1 (CBM) signalosome and NF-κB signaling inhibitors. CARD11 was found to interact directly with the viral phosphoprotein (P) through its CC1 domain and the X domain of P; this X domain also mediated the interaction between P and the viral large polymerase protein (L). The CARD11 CC1 domain and L competitively bound to P via the X domain that hindered the P-L interaction of the viral ribonucleoprotein (RNP) complex, resulting in a reduction of viral polymerase activity in a minigenome assay and inhibition of viral replication. Animal experiments further revealed that CARD11 contributed to viral replication inhibition and neuropathology in infected chicken brains. Taken together, our findings identify CARD11 as a brain-specific antiviral factor of NDV infection in avian species.IMPORTANCE Newcastle disease virus (NDV) substantially impacts the poultry industry worldwide and causes viral encephalitis and neurological disorders leading to brain damage, paralysis, and death. The mechanism of interaction between this neurotropic virus and the avian central nervous system (CNS) is largely unknown. Here, we report that host protein CARD11 presented brain-specific upregulated expression that inhibited NDV replication, which was not due to CARD11-Bcl10-MALT1 (CBM) complex-triggered activation of its downstream signaling pathways. The inhibitory mechanism of viral replication is through the CARD11 CC1 domain, and the viral large polymerase protein (L) competitively interacts with the X domain of the viral phosphoprotein (P), which hampers the P-L interaction, suppressing the viral polymerase activity and viral replication. An in vivo study indicated that CARD11 alleviated neuropathological lesions and reduced viral replication in chicken brains. These results provide insight into the interaction between NDV infection and the host defense in the CNS and a potential antiviral target for viral neural diseases.

[Study of the mechanism underlying the effect of SOCS3 rs4969170 A/G polymorphism on the occurrence of insulin resistance in chronic hepatitis C patients].

OBJECTIVE: To study the mechanism underlying the effect of the SOCS3 rs4969170 A/G alleles on the occurrence of insulin resistance (IR) in patients with chronic hepatitis C. METHODS: The promoter region of the SOCS3 gene was amplified by PCR,and luciferase expression vectors were constructed and transfected into HepG2,Huh7 cell lines.The relative luciferase activity of each expression vector was assessed by the dual luciferase reporter gene assay system.Western blotting was used to detect SOCS3 protein expression in PBMCs from groups of patients with the rs4969170 AA and AG genotypes.The state of IR in eight patients was evaluated by determining their HOMA-IR. RESULTS: The pGL3-A, PGL3-G and pGL3-control vectors showed significantly different luciferase expression in the HepG2 cells (0.121 00 ± 0.022 07,0.027 00+/-0.012 49 and 0.043 33 ± 0.005 51; F =48.068, P=0.001) and in the Huh7 cell lines (0.164 70 ± 0.007 10,0.027 33 ± 0.017 04 and 0.033 67 ± 0.014 98; F =115.137, P=0.001). The expression of SOCS3 protein was significantly higher in the rs4969170 AA genotype group than in the AG genotype group (1.22 ± 0.40 vs. 0.30 ± 0.19; t =4.149, P=0.006).The IR index of patients with the rs4969170 AA genotype and the AG genotype was 4.11 ± 2.62 and 1.47 ± 1.01 respectively.There were three patients with IR in the rs4969170 AA genotype group and one in the rs4969170 AG group. There was no statistically significant difference between the two genotype groups (t=1.881, P=0.109). CONCLUSIONS: The SOCS3 rs4969170 A haplotype may enhance transcriptional activity of the gene promoter to regulate gene expression, thereby increasing intracellular SOCS3 protein level and ultimately interfering with insulin signaling and causing IR in patients with chronic hepatitis C.

Circ_0087199 depletion attenuates lipopolysaccharides-induced human periodontal ligament cell injury through the miR-527/TLR4 axis.

BACKGROUND: Circular RNAs participate in the development of periodontitis. The present work aims to reveal the role and mechanism of circ_0087199 in human periodontal ligament cell (PDLC) injury during periodontitis. METHODS: PDLCs were treated with lipopolysaccharides (LPS) to establish a periodontitis cell model. Quantitative real-time polymerase chain reaction was used to detect the expression of circ_0087199, miR-527, toll-like receptor 4 (TLR4). Western blot analysis assay was performed to assess protein expression. Cell viability, proliferation, apoptosis and inflammation were investigated by cell counting kit-8, EdU assay, flow cytometry and enzyme-linked immunosorbent assay, respectively. Oxidative stress was evaluated by malondialdehyde assay kit and superoxide dismutase activity assay kit. The interaction between miR-527 and circ_0087199 or TLR4 was confirmed by a dual-luciferase reporter assay. RESULTS: Circ_0087199 and TLR4 expression levels were significantly increased, while miR-527 was decreased in the periodontal ligament tissues of periodontitis patients and LPS-stimulated PDLCs when compared with controls. LPS treatment inhibited cell viability and proliferation but induced cell apoptosis, inflammation and oxidative stress, whereas these effects were attenuated after circ_0087199 knockdown. Circ_0087199 bound to miR-527 and regulated LPS-caused PDLC damage by targeting miR-527. Additionally, the overexpression of TLR4, a target gene of miR-527, rescued miR-527 mimic-mediated effects on LPS-treated PDLCs. Further, the regulation of circ_0087199 toward TLR4 involved miR-527. CONCLUSION: Circ_0087199 knockdown attenuated LPS-induced apoptosis, inflammation and oxidative stress of PDLCs by regulating the miR-527/TLR4 pathway.

A combination of insulin and ubiquitin A20 promotes osteocalcin expression in adipose-derived stem cells.

Osteocyte generation can be used in bone defect repair; the generation efficiency needs to be further improved. This study aims to evaluate the role of ubiquitin A20 (A20) in facilitating the expression of osteocalcin in adipose-derived stem cells (ADSCs). In this study, adipose tissue was obtained from 10 healthy human subjects; ADSCs were isolated from the adipose samples. The ADSCs were transfected with core binding factor alpha 1 (Cbfa1) and/or insulin-like growth factor-1 receptor (IGF-1R). Expression of osteocalcin, A20 in ADSCs was assessed by quantitative RT-PCR (qRT-PCR) and Western blotting. Apoptosis of ADSCs was analyzed by flow cytometry. The results showed that after the gene transfection and stimulation of insulin, the ADSCs expressed high levels of osteocalcin. However, apoptotic ADSCs were induced by the activation of IGF-1R. Exposure to insulin down-regulated the expression of Bcl-xL and A20, and increased Bax, in ADSCs. The addition of exogenous A20 prevented the ADSC apoptosis. We conclude that activation of IGF-1R can induce apoptosis in ADSCs, which can be prevented by addition of exogenous A20.

[The difference of IL-28B polymorphisms between hepatitis C patients with and without cryoglobulinemia].

OBJECTIVE: To determine whether patients infected with chronic hepatitis C (CHC) show a differential distribution profile of IL-28B polymorphisms according to the presence of concomitant cryoglobulinemia. METHODS: Sixty-two consecutive CHC patients were enrolled in the study between December 2008 and December 2010. All patients received combination therapy of pegylated interferon alpha-2a (weekly, 180 g, subcutaneous injection) plus ribavirin (daily, 10to15 mg/kg body weight, oral) for 48 weeks, with individualized dosage adjustments according to the patient's clinical situation. Cryoglobulins were detected visibly by separation of cryoprecipitates in patient serum samples. Three IL-28B SNPs (rs8099917, rs12979860, and rs12980275) were detected by sequencing. Response to treatment was assessed by measuring serum levels of HCV RNA by quantitative PCR at baseline (prior to treatment initiation), during treatment (4 and 12 weeks after treatment initiation), end of therapy (48 weeks after treatment initiation), and post-treatment (24 weeks after end of therapy). The significance of between-group differences were assessed by the Chi-square and Fisher's exact tests. RESULTS: Cryoglobulinemia was detected in 43.5% (27/62) of the CHC patients and showed a female bias (59.3% vs. males: 34.3%, P = 0.05). Compared to CHC patients without cryoglobulinemia, the CHC patients with cryoglobulinemia showed significantly higher levels of HCV RNA at baseline (5.64+/-1.20 vs. 6.37+/-0.67, P less than 0.05) but lower frequencies of the IL28B rs8099917 TT genotype (94.3% vs. 63.0%, P = 0.002), rs8099917 T allele (97.1% vs. 81.5%, P = 0.003), and rs12979860 C allele (94.3% vs. 83.3%, P = 0.048). CHC patients with cryoglobulinemia and having the rs8099917 TT, rs12979860 CC, or rs12980275 AA genotype achieved a higher rate of sustained virological response. CONCLUSION: Cryoglobulinemia in CHC patients is associated with a differential distribution of IL-28B polymorphisms, and certain polymorphisms may be related to anti-viral treatment response.

Extracellular vesicles secreted by human gingival mesenchymal stem cells promote bone regeneration in rat femoral bone defects.

Extracellular vesicles (EVs), important components of paracrine secretion, are involved in various pathological and physiological processes of the body. In this study, we researched the benefits of EVs secreted by human gingival mesenchymal stem cells (hGMSC-derived EVs) in promoting bone regeneration, thereby providing new ideas for EVs-based bone regeneration therapy. Here, we successfully demonstrated that hGMSC-derived EVs could enhance the osteogenic ability of rat bone marrow mesenchymal stem cells and the angiogenic capability of human umbilical vein endothelial cells. Then, femoral defect rat models were created and treated with phosphate-buffered saline, nanohydroxyapatite/collagen (nHAC), a grouping of nHAC/hGMSCs, and a grouping of nHAC/EVs. The results of our study indicated that the combination of hGMSC-derived EVs and nHAC materials could significantly promote new bone formation and neovascularization with a similar effect to that of the nHAC/hGMSCs group. Our outcomes provide new messages on the role of hGMSC-derived EVs in tissue engineering, which exhibit great potential in bone regeneration treatment.

Local transplantation of GMSC-derived exosomes to promote vascularized diabetic wound healing by regulating the Wnt/ß-catenin pathways.

With the increasing number of diabetic patients, chronic wound healing remains a great challenge in clinical medicine. As one of the main components secreted by stem cells, the exosome is considered to be a promising candidate for promoting chronic wound healing. Here, gingival mesenchymal stem cell (GMSC)-derived exosomes (GMSC-Exo) were isolated and demonstrated to promote the proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs) by regulating the Wnt/ß-catenin signaling pathway in a diabetic-mimicking high glucose environment. In order to deliver GMSCs-Exo to the target site and prolong their local retention, porous microspheres consisting of poly-lactic-co-glycolic acid (PLGA), amphiphilic block copolymer (PLLA-PEG-PLLA), nano-hydroxyapatite (nHAP), and poly-ε-l-lysine (EPL) coating were fabricated through a double emulsion method and following surface treatment, hereafter referred to as PHE microspheres. PHE microspheres loaded with GMSCs-Exo were implanted into the full-thickness skin wound of a diabetic mouse model, resulting in significant vascularized wound healing when compared to a control group only injected with GMSCs-Exo suspension or filled with PHE microspheres. These findings indicated that the GMSCs-Exo-loaded porous microspheres could efficiently treat diabetic wounds and have promising potential for future clinical translations.

Steady Decline of HBV DNA Load under NAs in Lymphoma Patients and a Higher Level of qAnti-HBc Predict HBV Reactivation.

Background: Patients with lymphoma and chronic hepatitis B virus infection need to be treated with both chemotherapy and nucleotide analogue (NA) therapy. However, dynamic changes in HBV DNA loads with increasing chemotherapy cycles are lacking. It is unknown whether HBV replication markers, namely, the quantitative hepatitis B core antibody (qAnti-HBc), HBV RNA, and the hepatitis B virus core-related antigen (HBcrAg), are also markers for predicting HBV reactivation (HBVr). Methods: From 29 June 2010 to 6 December 2021, the data of patients with single-site diffuse large B-cell lymphoma and HBV infection (HBsAg+ and HBsAg-/anti-HBc+) were collected from a hospital medical record system, retrospectively. Serum HBV DNA loads (using real-time fluorescent quantitative PCR tests), qAnti-HBc levels (using a newly developed chemiluminescent particle immunoassay), HBV RNA levels (using the simultaneous amplification testing method based on real-time fluorescence detection), and HBcrAg levels (using a Lumipulse G HBcrAg assay) were tested, and factors related to HBVr were analyzed. Results: Under NAs, the HBV DNA loads of 69 HBsAg+ lymphoma patients declined from 3.15 (2.13-4.73) lg IU/mL to 1.00 (1.00-1.75) lg IU/mL, and further declined to 1.00 (1.00-1.04) lg IU/mL at the end of a 24-month follow-up. The qAnti-HBc levels decreased gradually during chemotherapy in HBsAg+ lymphoma patients (F = 7.090, p = 0.009). The HBV RNA and HBcrAg levels remained stable. A multivariate analysis revealed that higher qAnti-HBc levels (1.97 ± 1.20 vs. 1.12 ± 0.84 lg IU/mL, OR = 6.369, [95% CI: 1.523-26.641], p = 0.011) and higher HBV RNA levels (1.00 ± 1.13 vs. 0.37 ± 0.80 lg copies/mL, OR = 3.299, [95% CI: 1.229-8.854], p = 0.018) were related to HBVr in HBsAg-/anti-HBc+ lymphoma patients. Conclusions: HBV DNA loads declined under NAs during chemotherapy in lymphoma patients. In HBsAg-/anti-HBc+ lymphoma patients, a higher level of baseline serum qAnti-HBc and HBV RNA levels can predict the likelihood of HBVr during chemotherapy.

Periosteum and development of the tissue-engineered periosteum for guided bone regeneration.

BACKGROUND: Periosteum plays a significant role in bone formation and regeneration by storing progenitor cells, and also acts as a source of local growth factors and a scaffold for recruiting cells and other growth factors. Recently, tissue-engineered periosteum has been studied extensively and shown to be important for osteogenesis and chondrogenesis. Using biomimetic methods for artificial periosteum synthesis, membranous tissues with similar function and structure to native periosteum are produced that significantly improve the efficacy of bone grafting and scaffold engineering, and can serve as direct replacements for native periosteum. Many problems involving bone defects can be solved by preparation of idealized periosteum from materials with different properties using various techniques. METHODS: This review summarizes the significance of periosteum for osteogenesis and chondrogenesis from the aspects of periosteum tissue structure, osteogenesis performance, clinical application, and development of periosteum tissue engineering. The advantages and disadvantages of different tissue engineering methods are also summarized. RESULTS: The fast-developing field of periosteum tissue engineering is aimed toward synthesis of bionic periosteum that can ensure or accelerate the repair of bone defects. Artificial periosteum materials can be similar to natural periosteum in both structure and function, and have good therapeutic potential. Induction of periosteum tissue regeneration and bone regeneration by biomimetic periosteum is the ideal process for bone repair. CONCLUSIONS: Periosteum is essential for bone formation and regeneration, and it is indispensable in bone repair. Achieving personalized structure and composition in the construction of tissue engineering periosteum is in accordance with the design concept of both universality and emphasis on individual differences and ensures the combination of commonness and individuality, which are expected to meet the clinical needs of bone repair more effectively. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: To better understand the role of periosteum in bone repair, clarify the present research situation of periosteum and tissue engineering periosteum, and determine the development and optimization direction of tissue engineering periosteum in the future. It is hoped that periosteum tissue engineering will play a greater role in meeting the clinical needs of bone repair in the future, and makes it possible to achieve optimization of bone tissue therapy.

Extracellular vesicles: A potential future strategy for dental and maxillofacial tissue repair and regeneration.

Extracellular vesicles (EVs), nano-sized bilayer membrane structures containing lipids, proteins and nucleic acids, play key roles in intercellular communication. Compared to stem cells, EVs have lower tumorigenicity and immunogenicity, are easier to manage and cause fewer ethic problems. In recent years, EVs have emerged as a potential solution for tissue regeneration in stomatology through cell-free therapies. The present review focuses on the role of EVs in dental and maxillofacial tissue repair and regeneration, including in dental and periodontal tissue, maxilla and mandible bone, temporomandibular joint cartilage, peripheral nerve and soft tissue. We also make a brief overview on the mechanism of EVs performing functions. However, limitations and challenges in clinical application of EVs still exist and should be addressed in future researches.

[Compositions and metabolic footprints of soil nematode communities under different alfalfa-crop planting patterns in semi-arid region of the Loess Plateau, Northwest China.] / 黄土高原半干旱区不同苜蓿-作物种植方式下土壤线虫群落组成及代谢足迹.

Soil nematode communities play an important role in ecosystem material cycling and energy flow. In this study, soil samples were collected from three rotation systems in southern Ningxia mountainous region, including alfalfa continuous cropping (A-A), alfalfa-corn rotation (A-C), alfalfa-potato rotation (A-P). Soil physicochemical properties, nematode community composition and their metabolic footprints were measured. Compared with the A-A plot, the concentrations of soil organic carbon (SOC) and total nitrogen (TN) were significantly increased by 4.6% and 7.4% for SOC, 4.0% and 5.2% for TN in the A-C and A-P plots, respectively. Soil microbial biomass carbon and nitrogen were significantly higher in the A-C and A-P plots when compared with the A-A plot. The total abundance of soil nematodes in the A-C and A-P plots was higher by 49.5% and 93.7% than that in the A-A plot, respectively, with the dominant trophic group being changed to omnivores-predators from plant parasite. Compared to the A-A plot, the plant parasite index (PPI) was decreased significantly in the A-C and A-P plots, indicating that the harm of plant-parasites was reduced in soil food web. The nematode channel ratio (NCR) in the A-C and A-P plots were higher than that in the A-A plot, indicating that the role of bacterial decomposition was enhanced in soil organic matter decomposition. The maturity index (MI), the total nematode metabolic footprint, enrichment footprint, structure footprint in the A-C and A-P plots were all significantly higher than those in the A-A plot, suggesting that the structure and function of soil food web were more mature and stable, and the productivity and metabolic activity of nematodes were significantly enhanced. In general, the alfalfa-crop rotations improved soil nutrient status and reduced the disturbance degree of soil food web. Furthermore, soil ecosystem developed in the stable and healthy direction, which would be beneficial to the sustainable development of agriculture.

Osteogenic role of endosomal chloride channels in MC3T3-E1 cells.

ClC-3, ClC-4, and ClC-5 belong to the voltage gated chloride channels (ClCs) and facilitate the endosomal acidification. The mutations of these endosomal chloride channel genes cause different genetic diseases with various bone disorders. We hypothesized that these endosomal ClCs might be involved in the bone development or osteoblast differentiation. Here we used MC3T3-E1 osteoprogenitor cell line and primarily cultured mouse osteoblasts and detected the expression of Clcn3, Clcn4, and Clcn5 in these cells. We analyzed the relationships between three endosomal ClCs and the osteogenic phenotype using osteoinductive treatment, overexpressing of ClCs and RNAi of ClCs. We found the increased mRNA levels of osteogenic markers [alkaline phosphatase (Alp), osteocalcin (Oc), bone sialoprotein (Bsp), and runt-related transcription factor 2 (Runx2)] were in parallel to that of Clcn3, Clcn4 and Clcn5 with osteoinductive treatment and overexpressed ClCs. Overexpressed ClCs were localized in intracellular periphery and also promoted the mineralization of cells in vitro. While RNAi mediated gene silencing of ClC-3, ClC-4, and ClC-5 down regulated the expression of the four osteogenic markers. The positive relationship between endosomal ClCs and the osteogenic markers suggested a new function of endosomal ClCs in osteogenic differentiation.

The clinical and histological characteristics and outcomes of drug induced chronic liver injury after removing causative drugs.

BACKGROUND/AIMS: To investigate characteristics and outcomes of drug induced chronic liver injury after removing causative drugs. METHODOLOGY: Between Apr 2001 and Mar 2010, patients diagnosed as drug induced liver injury and with chronic courses, were observed. Chronic liver injury was defined as persistent biochemical abnormality for more than 6 months after drugs withdrawal. RESULTS: Forty patients were observed with mean age 41 years and female 28 (70%). Of the 40 patients, 32 (80%) cases showed hepatocellular injury at the onset of liver damage, 4 (10%) cases showed cholestatic injury, and 4 (10%) cases showed mixed injury. Of 32 patients with hepatocellular injury, 24 (75%) cases resemble acute icteric hepatitis at the onset of liver damage. Of 27 patients with hepatocellular injury who underwent liver biopsy, 14 (51.9%) cases showed chronic hepatitis with a mean follow up of 17 months. Of total 40 patients, 15 (37.5%) patients resolved; 18 (45%) cases remained persistent liver injury, 4 (10%) cases developed cirrhosis, 3 (7.5%) cases died. Herbs (45.5%) are the commonest drugs implicated in chronic liver injury. CONCLUSIONS: Most cases with drug induced chronic liver injury after removing causative drugs resemble acute icteric hepatitis at the onset of liver damage. Some patients can resolve, some may progress to cirrhosis. Herbs are important drugs for drug induced chronic liver injury.

Exosomes from oral tissue stem cells: biological effects and applications.

As natural nanoparticles, exosomes are a type of extracellular vesicles that are enclosed by a lipid bilayer and contain various cargos, including miRNA, mRNA, DNA and proteins. Exosomes have rapidly gained attention as a highly promising cell-free therapy. Because the cargo of exosomes changes with the changes in parent cells and status, exosomes from different types of cells may exhibit different biological effects. Considering the particularity of oral tissue stem cells, their exosomes were isolated and used to examine their related biological functions and the possibility of replacing stem cells. A variety of exosomes of oral tissue stem cells were studied, and the results revealed many special biological characteristics of these exosomes and their parent cells, especially immunomodulation, osteogenesis, odontogenesis, neuroprotection, nerve regeneration, wound healing, skin regeneration and vascularization. The oral tissue stem cell exosomes may be loaded with drugs or genes and act as tools for tumor treatment. The relevant results showed that exosomes from oral tissue stem cells were potent therapeutic tools. The present review focuses on the biological function and application of oral tissue stem cell-derived exosomes.

Msx2 plays an important role in BMP6-induced osteogenic differentiation of two mesenchymal cell lines: C3H10T1/2 and C2C12.

Bone morphogenetic proteins (BMPs), have been shown to enhance the osteogenic differentiation of mesenchymal cells (MCs) and to promote bone formation. BMP6 is known to play an important role in the process of MCs towards osteogenic differentiation by virtue of their osteoinductive and cell type specific proliferative activity. However, the molecular mechanism relate to BMP6 osteoinductive activity is still unclear and continues to warrant further investigation. Msx2 is a member of the homeobox gene family of transcription factors and promotes calcification. Hence, we wondered if it might also play a role in BMP6-induced osteogenesis. In this study, two mouse mesenchymal cell lines were treated with BMP6, adenovirus-Msx2 (Ad-Msx2) or adenovirus-siMsx2 (Ad-siMsx2). Based on the results of mRNA and protein expression, it was indicated that BMP6 could enhance the expression of Msx2 and activate the phosphorylation of Smad 1/5/8, p38 and ERK1/2. Being transfected by Ad-Msx2, the BMP6-induced activation of phosphorylation was significantly promoted. On the contrary, two cell lines transfected by Ad-siMsx2 presented an inhibited expression of three phosphorylated proteins even after being induced by BMP6. The evaluation of ALP, OPN, OC and calcium deposits revealed the osteogenic results those were corresponding to the results of mRNA and protein. Taken together, these findings can be a novel viewpoint for the understanding of the mechanisms of BMP6-induced osteogenesis and provide therapeutic targets of bone defect.

[Characteristics of soil microbial and nematode communities under artificial Medicago sativa grasslands with different cultivation years in semi-arid region of Loess Plateau, Northwest China]. / 黄土高原半干旱区不同种植年限紫花苜蓿人工草地土壤微生物和线虫群落特征.

The establishment of Medicago sativa artificial grasslands is an important practice of grassland vegetation restoration in the Loess Plateau. Understanding community characteristics of soil microbes and nematodes can provide important information for evaluating and controlling ecolo-gical and environmental effects of vegetation restoration. In this study, we used M. sativa artificial grasslands with four different cultivation years (1, 2, 6 and 12 years) in southern Ningxia mountainous region, with a farmland and a natural grassland as control, to explore changing trends of the two biological communities during artificial grassland restoration in semi-arid region of the Loess Plateau. The results showed that: 1) After the conversion of farmland to M. sativa grassland, Chao1, ACE and Shannon diversity indices of soil bacterial community increased firstly and then decreased, which reached the maximum after six years of M. sativa grassland establishment. For soil fungal community, Shannon diversity index was lower in 6 and 12 year-old M. sativa grasslands than in the other two artificial grasslands, and the community composition differed across restoration years. 2) With the increases of restoration years, the abundance of soil nematodes showed a similar changing trend with Shannon diversity index of bacterial community. The composition of nematode community did not greatly differ between the 6-year-old M. sativa grassland and farmland, while that in 12-year-old artificial grassland was more similar to that in natural grassland. The proportion of bacterivorous and plant-feeding nematodes, as well as plant parasitic index and nematode channel index of nematode community,were increased, while the proportion of fungivores and omnivores-predators and maturity index were decreased. 3) During the restoration, changes in soil organic carbon, total nitrogen and available phosphorus greatly affected soil microbial community, which could further influence soil nematode community. There were significant correlations between dominant microbial phyla and trophic groups of soil nematodes, implying the possible effects of soil microbes on nematode community. In M. sativa artificial grassland with different establishment years, changes in plant biomass and diversity might significantly affect soil nematode and microbial communities through affecting their food conditions.

Activation of CB2 cannabinoid receptors: a novel therapeutic strategy to accelerate osseointegration of dental implants.

Dental implants have been widely inserted in jaw bones as substitutes for teeth to restore oral function over the last few decades, but there still remains a major challenge in difficult clinical situations with poor bone quality and quantity or some diseases like osteoporosis. In the meantime, the bone healing phase and convalescence time after dental implantation should be curtailed to reduce the inconvenience for patients. The osseointegration has been considered the most appropriate bone-implant interface and is crucial for the clinical success of dental implants. The endocannabinoid system is present in some mammalian organs and tissues. Recently, endocannabinoids and their receptors, CB2 cannabinoid receptors, have been discovered in the skeleton. Osteoblasts, the bone-forming cells, and osteoclasts, the bone-resorbing cells, synthesize the endocannabinoids anandamide and 2-arachidonoylglycerol (2-AG) and express CB2 cannabinoid receptors. The activation of CB2 contributes to the maintenance of bone mass by stimulation of osteoblastic bone formation and inhibition of osteoclastic bone resorption. Therefore, we hypothesize that the activation of CB2 with a CB2-specific agonist, such as HU-308, might be a novel therapeutic strategy to accelerate osseointegration of dental implants. HU-308, incorporated into dental implants, might be a desirable agent used in implant dentistry for a higher clinical success rate and a curtailed convalescence time.