Sesquiterpenoids from the leaves of Sarcandra glabra.

Sarglanoids A-F, six new sesquiterpenoids belonging to eudesmane (1-5) and eremophilane (6) types, were isolated from the leaves of Sarcandra glabra, a famous traditional Chinese medicine (TCM). Their structures including absolute configurations were elucidated through extensive spectroscopic analysis and electronic circular dichroism (ECD) calculations. Compounds 1-2 were rare N-containing eudesmane-type sesquiterpenoids. Compound 3 exhibited inhibitory activity against nitric oxide (NO) production in lipopolysaccharides (LPS)-induced RAW 264.7 cells with IC50 values at 20.00 ± 1.30 µmol·L-1. These findings provide scientific evidence for sesquiterpenoids as the material foundation of S. glabra.

Chemical Structures and Biological Activities of Limonoids from the Genus Swietenia (Meliaceae).

Swietenia is a genus in the plant family Meliaceae. This genus contains seven to eight known species, found in the tropical and subtropical regions of the Americas and West Africa. Thus far, more than 160 limonoids have been isolated from four species of the genus Swietenia. Limonoids are rich in structure type and biological activity, and these compounds are the main active components in the Swietenia species. This paper will give a comprehensive overview of the recent phytochemical and pharmacological research on the terpenes from Swietenia plants and encourage further drug discovery research.

Marginal bone loss around non-submerged implants is associated with salivary microbiome during bone healing.

Marginal bone loss during bone healing exists around non-submerged dental implants. The aim of this study was to identify the relationship between different degrees of marginal bone loss during bone healing and the salivary microbiome. One hundred patients were recruited, and marginal bone loss around their implants was measured using cone beam computed tomography during a 3-month healing period. The patients were divided into three groups according to the severity of marginal bone loss. Saliva samples were collected from all subjected and were analysed using 16S MiSeq sequencing. Although the overall structure of the microbial community was not dramatically altered, the relative abundance of several taxonomic groups noticeably changed. The abundance of species in the phyla Spirochaeta and Synergistetes increased significantly as the bone loss became more severe. Species within the genus Treponema also exhibited increased abundance, whereas Veillonella, Haemophilus and Leptotrichia exhibited reduced abundances, in groups with more bone loss. Porphyromonasgingivalis, Treponemadenticola and Streptococcus intermedius were significantly more abundant in the moderate group and/or severe group. The severity of marginal bone loss around the non-submerged implant was associated with dissimilar taxonomic compositions. An increased severity of marginal bone loss was related to increased proportions of periodontal pathogenic species. These data suggest a potential role of microbes in the progression of marginal bone loss during bone healing.

Vitamin D3 and insulin combined treatment promotes titanium implant osseointegration in diabetes mellitus rats.

This study investigated the effect of insulin and vitamin D(3) (VD(3)) treatment on implant osseointegration in diabetic mellitus (DM) rats. DM was induced by administration of streptozotocin in rats, which received implants insertion in the femur. Then animals were subjected to different treatment and divided to the following group: control, diabetic, insulin-treated diabetic, VD(3)-treated diabetic, insulin and VD(3) combination-treated diabetic rats. The glucose levels and weight of rats were periodically evaluated, and serum 25(OH)D(3) levels in rats were measured at the end of the experiment. Animals were sacrificed at 12 weeks after surgery, the peri-implant trabecular microstructure, implant fixation and implant osseointegration were measured by microscopic computerized tomography (micro-CT) evaluation, push-out test and histomorphometric analysis. Diabetic rats displayed significantly higher blood glucose level, lower body weight, lower serum 25(OH)D(3) levels, and less implant osseointegration than controls. Insulin treatment showed restorative effect on body weight and serum 25(OH)D(3) levels of diabetic rats, but the blood glucose level in diabetic rats were still substantially higher compared to controls after 14 days therapy of insulin. Combined treatment restored hyperglycemia in diabetic rats to be normal, and reversed the impaired osseointegration capacity of implants, with the bone volume ratio and percent osseointegration increased by 1.37-fold and 1.6-fold in micro-CT evaluation, the maximal push-out force and ultimate shear strength by 1.3-fold and 2.1-fold in push-out test, and the bone-to-implant contact and bone area ratio increased by 2.57-fold and 1.44-fold in histomorphometric analysis. Monotreatment also enhanced implant fixation, but less. These results indicated that insulin and VD(3) combined treatment may be an effective approach to enhance implant fixation in diabetic rats, but whether the results could be extrapolated to human needs further study.

1,25(OH)2D3 inhibits the deleterious effects induced by high glucose on osteoblasts through undercarboxylated osteocalcin and insulin signaling.

Diabetes mellitus (DM) is associated with multiple skeletal disorders, and vitamin D may play a functional role in the preservation of glucose tolerance. However, the relationship between vitamin D deficiency and DM is not well known. The aim of this study was to investigate the potential molecular link between 1,25(OH)(2)D(3) regulation and glucose homeostasis. Rat primary osteoblasts were cultured in different conditioned medium: normal glucose, high glucose, high glucose and insulin, high glucose and 1,25(OH)(2)D(3), high glucose and insulin and 1,25(OH)(2)D(3). The activity of osteoblasts was measured by cell viability, alkaline phosphatase and osteocalcin assay. The potential mechanism of how 1,25(OH)(2)D(3) affect insulin sensitivity was investigated by the assay of insulin receptor (IR) and vitamin D receptor (VDR) expression, and undercarboxylated osteocalcin (ucOC) level. The combined treatment has the strongest effect of inhibiting the deleterious effects induced by high glucose on osteoblasts, and it promoted the %ucOC value to approximately 40%, which is much higher than that in high glucose without treatment. Levels of IR and VDR of osteoblasts in combined treatment culture increased significantly compared with that in high glucose without treatment. So maybe 1,25(OH)(2)D(3) promotes insulin sensitivity of osteoblasts by activating insulin signaling and simultaneously stimulating ucOC secretion, which in turn regulate insulin production and sensitivity. 1,25(OH)(2)D(3) might be beneficial not only for diabetes, but also, for osteoporosis by promoting bone formation.

Response of osteoblasts to low fluid shear stress is time dependent.

The process of mechanotransduction of bone, the conversion of a mechanical stimulus into a biochemical response, is known to occur in osteoblasts in response to fluid shear stress. In order to understand the reaction of osteoblasts to various times of flow perfusion, osteoblasts were seeded on three-dimensional scaffolds, and cultured in the following conditions: continuous flow perfusion, intermittent flow perfusion, and static condition. We collected samples on day 4, 8 and 12 for analysis. Osteoblast proliferation was demonstrated by cell proliferation and scanning electron microscopy assay. Additionally, the expression of known markers of differentiation, including alkaline phosphatase and osteocalcin, were tested by qRT-PCR and alkaline phosphatase activity assay, and the deposition of calcium was used as an indicator of mineralization demonstrated by calcium content assay. The results supported that low fluid shear stress plays an important role in the activation of osteoblasts: enhance cell proliferation, increase calcium deposition, and promote the expression of osteoblastic markers. Furthermore, the continuous flow perfusion is a more favorable environment for the initiation of osteoblast activity compared with intermittent flow perfusion. Therefore, the force and time of fluid shear stress are important parameters for osteoblast activation.

[Bone histomorphometry study in agglutination of femoral condyle of dog after being compressed].

OBJECTIVE: This study simulated clinical implant surgery using squeeze technique by establishing a rational animal model. To measure the morphologic parameters in order to observe the agglutination of the cancellous bone after being compressed. The study wanted to get some favourable support of implant squeeze technique in bone healing and obtaining primary stabilities of implants, so as to provide some reasonable and valid guidance in the application and improvement of implant squeeze technique. METHODS: The cancellous bone in condyles of femur of dog had been chosen as the experimental position, prepared the implant holes using squeeze technique according to different compressing extent (0, 0.6, 1.2, 2.0 mm), and then inserted the corresponding implants into them. After different healing periods (1, 2, 4, 12 weeks), the mongrel dogs were sacrificed and the hard tissue slices were made and then the morphologic parameters were measured. RESULTS: The morphologic parameter of the bone tissue shows that after being compressed, the trabecular bone thickness was almost constant, while the trabecular bone number increased, and the trabecular bone spacing decreased, obviously in the 1-week and 2-week groups. The differences went down gradually along with the extend of healing time. CONCLUSION: The clinical implant surgery using squeeze technique can improve peri-implant bone density so it is good for obtaining primary stabilities of implants.

The relationship between IL-1 gene polymorphism and marginal bone loss around dental implants.

PURPOSE: Early marginal bone loss around dental implants has been found during the bone healing period before stage II surgery despite a lack of apparent cause, and the etiology of this bone loss is unclear. This study was designed to investigate whether interleukin-1 gene polymorphism is associated with the marginal bone loss around the implants before stage II. MATERIALS AND METHODS: One hundred forty-three implants were placed in 59 patients. The patients were divided into 2 groups: 1) test group: with 1 or more marginal bone loss greater than 0.5 mm; and 2) control group: with marginal bone resorption less than 0.5 mm. Polymorphisms of the IL-1alpha and IL-1beta genes (IL-1A-889, IL-1B-511, and IL-1B+3954) were detected by restriction fragment length polymorphism using Ncol, AvaI, and TaqI digestion after polymerase chain reactions. RESULTS: The frequency of IL-1B-511 II/II was significantly higher among patients in early marginal bone loss (+) group than those in early marginal bone loss (-) group (P < .05). Multiple logistic regressions showed the OR of the II/II versus the I/I+I/II of the IL-1B-511 genotype was 3.933 between the 2 groups. The difference was statistically significant (P < .05). There was no significant difference between the other risk factors. CONCLUSION: These results suggest that the IL-1B-511 II/II genotype in individuals is associated with early marginal bone loss around implants.

[A clinical study of immediate dental implant and immediate restoration].

OBJECTIVE: To evaluate the clinical results of immediate implant and immediate restoration and to discuss the applying principles of these techniques. METHODS: Fourteen cases underwent immediate implant surgery for 37 dental implants immediately after the teeth or roots were extracted. Among them, 6 cases (14 implants) received immediate restoration after implant placement. The second stage operation and final restoration were performed 4 months on average postoperatively, and the mean follow-up time was 22 months. RESULTS: Two implants from 1 case were lost at 3 weeks after immediate implant and immediate restoration. The rest cases achieved good clinical results. Accumulative 4-year survival rate was 94.6%. CONCLUSIONS: The result of immediate implant and immediate restoration is predictable if the cases are properly selected.