Association between chronic periodontitis and the risk of Alzheimer's disease: combination of text mining and GEO dataset.

BACKGROUND: Although chronic periodontitis has previously been reported to be linked with Alzheimer's disease (AD), the pathogenesis between the two is unclear. The purpose of this study is to analyze and screen the relevant and promising molecular markers between chronic periodontitis and Alzheimer's disease (AD). METHODS: In this paper, we analyzed three AD expression datasets and extracted differentially expressed genes (DEGs), then intersected them with chronic periodontitis genes obtained from text mining, and finally obtained integrated DEGs. We followed that by enriching the matching the matching cell signal cascade through DAVID analysis. Moreover, the MCODE of Cytoscape software was employed to uncover the protein-protein interaction (PPI) network and the matching hub gene. Finally, we verified our data using a different independent AD cohort. RESULTS: The chronic periodontitis gene set acquired from text abstracting was intersected with the previously obtained three AD groups, and 12 common genes were obtained. Functional enrichment assessment uncovered 12 cross-genes, which were mainly linked to cell morphogenesis involved in neuron differentiation, leading edge membrane, and receptor ligand activity. After PPI network creation, the ten hub genes linked to AD were retrieved, consisting of SPP1, THY1, CD44, ITGB1, HSPB3, CREB1, SST, UCHL1, CCL5 and BMP7. Finally, the function terms in the new independent dataset were used to verify the previous dataset, and we found 22 GO terms and one pathway, "ECM-receptor interaction pathways", in the overlapping functional terms. CONCLUSIONS: The establishment of the above-mentioned candidate key genes, as well as the enriched signaling cascades, provides promising molecular markers for chronic periodontitis-related AD, which may help the diagnosis and treatment of AD patients in the future.

Wood-inhabiting fungi in southern China 5. New species of Theleporus and Grammothele (Polyporales, Basidiomycota).

During the examination of specimens of Theleporus and Grammothele (Polyporales, Basidiomycota) from tropical China, three new species, Theleporus membranaceus, T. minisporus and Grammothele denticulata, were identified based on both morphological and phylogenetic analyses. They are described and illustrated. T. membranaceus is characterized by its extremely thin basidiocarps (0.12 mm), small pores (7-10 per mm) and ellipsoid to broadly ellipsoid basidiospores. T. minisporus has the smallest basidiospores among the species in the genus. Grammothele denticulata is distinguished in the genus by gray pores, continuous hymenia over dissepiment edge and cylindrical basidiospores with tapering apex. Two annotated identification keys are provided for species thus far accepted in Theleporus and Grammothele. The phylogenetic relationships of Theleporus and Grammothele were inferred based on nITS sequences and are briefly discussed. The molecular evidence showed that Theleporus and Grammothele belong to the core polyporoid clade.

Transdermal delivery of a somatostatin receptor type 2 antagonist using microneedle patch technology for hypoglycemia prevention.

Hypoglycemia is a serious and potentially fatal complication experienced by people with insulin-dependent diabetes. The complication is usually caused by insulin overdose, skipping meals, and/or excessive physical activities. In type 1 diabetes (T1D), on top of impaired pancreatic α-cells, excessive levels of somatostatin from δ-cells further inhibit glucagon secretion to counteract overdosed insulin. Herein, we aimed to develop a microneedle (MN) patch for transdermal delivery of a peptide (PRL-2903) that antagonizes somatostatin receptor type 2 (SSTR2) in α-cells. First, we investigated the efficacy of subcutaneously administered PRL-2903 and identified the optimal dose (i.e., the minimum effective dose) and treatment scheduling (i.e., the best administration time for hypoglycemia prevention) in a T1D rat model. We then designed an MN patch using a hyaluronic acid (HA)-based polymer. The possible effect of the polymer on stabilizing the native structure of PRL-2903 was studied by molecular dynamics (MD) simulations. The results showed that the HA-based polymer could stabilize the PRL-2903 structure by restricting water molecules, promoting intra-molecular H-bonding, and constraining torsional angles of important bonds. In vivo studies with an overdose insulin challenge revealed that the PRL-2903-loaded MN patch effectively increased the plasma glucagon level, restored the counter-regulation of blood glucose concentration, and prevented hypoglycemia. The proposed MN patch is the first demonstration of a transdermal microneedle patch designed to deliver an SSTR2 antagonist for the prevention of hypoglycemia. This counter-regulatory peptide delivery system may be applied alongside with insulin delivery systems to provide a more effective and safer treatment for people with insulin-dependent diabetes.

A carboxymethyl chitosan and peptide-decorated polyetheretherketone ternary biocomposite with enhanced antibacterial activity and osseointegration as orthopedic/dental implants.

Carbon fiber-reinforced polyetheretherketone (CFRPEEK) possesses biomechanical properties such as elastic modulus similar to human bones and is becoming a dominant alternative to replace the traditional metallic implants. The defective osseointegration and bacterial infection risk of CFRPEEK, however, impede its clinical adoption. In the current study, a newly-developed carbon fiber-reinforced polyetheretherketone/nanohydroxyapatite (CFRPEEK/n-HA) ternary biocomposite was functionalized by covalently grafting carboxymethyl chitosan (CMC) followed by the decoration of a bone-forming peptide (BFP) assisted via the polydopamine tag strategy. Antibacterial test with Staphylococcus aureus (S. aureus) indicated that the CMC and peptide-conjugated substrates (pep-CMC-CFRPEEK/n-HA) significantly suppressed bacterial adhesion. In vitro cell attachment/growth, spreading assay, alkaline phosphatase activity, real-time PCR analysis, osteogenesis-related protein expression and calcium mineral deposition all disclosed greatly accelerated adhesion, proliferation and osteo-differentiation of human mesenchymal stem cells (hMSCs) on the pep-CMC-CFRPEEK/n-HA biocomposite due to the additive effect of the CMC polysaccharide and the small osteoinductive peptide. More importantly, in vivo evaluation of the beagle tibia model by means of micro-CT, histological analysis, SEM observation and fluorescent labeling confirmed the remarkably boosted bioactivity and osteointegration. The CFRPEEK/n-HA ternary composite with the dual functions of bacterial adhesion reduction and osteointegration promotion holds great potential as a bioactive implant material in orthopedic/dental applications based on this scheme.

[Study on injectable bioactive bone repairing material of nano-hydroxyapatite and polyamide-66 composite].

The aim of this study was to evaluate the injectability, histocompatibility, function and other properties of the injectable bioactive bone repairing material of nano-hydroxyapatite and polyamide-66 (n-HA/PA66) composite. The XRD pattern, the relationship between the injectability and liquid-powder ratio, setting time and liquid-powder ratio, compressive strength and liquid-powder ratio were assessed. The size of the composite was determined to be 70 nm in length and 30 to 50 nm in width, and the molecular weight of polyamides-66 was 18000. The diameter of pores of the composite was about 200 to 400 micrometer. To evaluate the histocompatibility and function, 8 male dogs were studied with the injectable n-HA/PA66 composite implanted in the artificial defected alveolus of mandible on only one side to be compared with the intact alveolus on the other side. The specimens were taken at 4, 8, 12, 16 months after the implantation and the results were evaluated. The XRD pattern of the solidificated n-HA/PA66 composite was the same as the powdered n-HA/PA66 composite. The injectable n-HA/PA66 composite had a good injectability, 25 to 30 minutes setting time and about 37 MPa compressive strength when the liquid-powder ratio was 0.50. The healing of the gingiva was well at the implanted areas in all animals. The height of the repaired alveolar bone was obvious higher than that of the blank control. The earlier sign of ossification was histologically observed at 16 weeks after implantation. The injectable n-HA/PA66 composite has good biocompatibility and osteoconductive property. As an injectable material, with good maneuverability, it is useful for repairing irregular bone defects, especially in oral and maxillofacial surgery.

[Research on the microstructure of antibacterial nanocomposite membrane and it's biocompatibility as a guided bone regeneration membrane].

OBJECTIVE: To study the microstructure of the Ag-nHA-nTiO2/PA66 membrane and investigate its biocompatibility. METHODS: The microstructure of Ag-nHA-nTiO2PA66 membrane and e-polytetra fluoroethylene (e-PTFE) membrane were observed by light microscope and scanning electron microscope(SEM). MG63 osteoblast-like cells were cultured on the two kinds of membrane and blank group. The cell proliferation was checked by methyl thiazolyl tetrazolium (MTT) method and alkaline phosphatase (ALP) activity was detected by enzyme linked immunosorbent assay (ELISA). The adhesion and proliferation of the cells on the two kinds of membrane was observed by SEM. RESULTS: The Ag-nHA-nTiO2/PA66 membrane was composed of the obverse face and the opposite face. The obverse face was porous and the opposite face was smooth. Microstructures of the obverse and the opposite face of the e-PTFE membrane were same. The e-PTFE membrane showed many tiny lined cracks in elliptic structure. MTT assay and ALP measurement showed that there were no significant difference between each of the two membrane groups and the blank (P > 0.05). The adhesion and proliferation of cells on the Ag-nHA-nTiO2/PA66 membrane were better than the e-PTFE membrane. CONCLUSION: Ag-nHA-nTiO2/PA66 membrane has no negative effects on the growth of osteoblast-like cells. Ag-nHA-nTiO/PA66 membrane is biocompatible and its microstructure is appropriate as a guided bone regeneration materials.

[The experimental study of PDLLA/rhBMP-2 compound screws for internal fixation of mandibular fracture].

OBJECTIVE: To study the effect of poly D,L-lactic acid (PDLLA) screws with PDLLA-rhBMP compound on bone regeneration in the screw holes and fracture ends of dog mandibles. METHODS: A self-control study was carried out in 4 dogs. PDLLA/rhBMP-2 compound screws were implanted to fix the mental fractures and PDLLA screws were used as control. The samples from mandibles were collected at 4, 8, 12, 16 weeks after implantation and observed by radiography and histology. RESULTS: All dogs showed a greater degree of bone regeneration around PDLLA/rhBMP-2 screws than PDLLA ones and all fractures were fixed and healed well. CONCLUSION: The PDLLA-rhBMP screw has a better effect of inducing osteogenesis than PDLLA screw, and is able to exert a good fixation to fracture.

[Experimental study on the reconstruction of mandibular defects with a new bioactive artificial bone nano-hydroxyapatite/polyamide-66 in dogs].

OBJECTIVE: This study was designed to investigate reconstruction of segmental defect in the mandible using a new bionic materials of nano-hydroxyapatite -polyainides-66 (n-HA/PA66). METHODS: Two defects (15 mm x 10 mm x 5 mm) were created in the mandibular bodies of dogs. One of defects was reconstructed with n-HA/PA66, another not repaired as a blank control. At 2, 4, 8, 12, 16 weeks after operation. Evaluation of effects of n-HA/PA66 on reconstruction of the mandibular defects was carried out by means of radiography and histology. RESULTS: From 2 to 8 weeks after operation, some fiber tissue grew into the space between n-HA/PA66 and mandibular bone. The ossification was observed at 12 weeks post-operation. At 16 weeks, the n-HA/PA66 was connected directly to the mandibular bone by the newborn bone. CONCLUSIONS: The new artificial bone of n-HA/PA66 has the effects of osteoconduction and osteoinduction, with a good biocompatibility and is an ideal bone substitute material for reconstruction of mandibular defect.