A long-acting pegylated recombinant human growth hormone (Jintrolong® ) in healthy adult subjects: Two single-dose trials evaluating safety, tolerability and pharmacokinetics

WHAT IS KNOWN AND OBJECTIVE

Jintrolong^® is a pegylated recombinant human growth hormone (rhGH) (PEG-rhGH) developed for weekly subcutaneous (sc) injection. The current human tolerability trial and pharmacokinetics (PK) trial evaluated the safety, tolerability and PK of single-dose Jintrolong^® injection in healthy adult subjects.

METHODS

Both trials were single-centre, randomized, open-label and single-dose studies. In the human tolerability trial, 34 healthy subjects were randomized to receive single-dose Jintrolong^® sc injection (0.01, 0.06, 0.2, 0.5 or 0.8 mg/kg) or placebo. In the PK study, 30 healthy male subjects were evenly randomized into 3 groups to receive single-dose Jintrolong^® sc injection (0.1, 0.2 or 0.4 mg/kg), and the subjects receiving 0.4 mg/kg Jintrolong^® were given a single sc injection of conventional rhGH (0.067 mg/kg) after a 14-day washout period. Safety and PK profiles of Jintrolong^® were evaluated.

RESULTS AND DISCUSSION

Jintrolong^® was well tolerated with no serious adverse events or local injection responses. The PK trial showed that the plasma growth hormone concentration elevated quickly and stayed at peak level between 12 and 48 hours post-Jintrolong^® injection, then decreased gradually back to baseline within 168 hours. Compared to single-dose conventional rhGH, Jintrolong^® at all doses demonstrated significantly longer half time and time to maximum plasma concentration, lower clearance and higher systemic drug exposure, indicating prolonged presence of GH in the subjects' circulation. Additionally, systemic exposure to Jintrolong^® increased in a dose-dependent manner.

WHAT IS NEW AND CONCLUSION

Single-dose Jintrolong^® injection was well tolerated in healthy adult subjects, and the maximum tolerable dose was no lower than 0.8 mg/kg. Jintrolong^® was long-acting with the potential for weekly administration.

[Clinical features of post-splenectomy pulmonary hypertension and effects of its target therapy]

Objective: To analyze the clinical features of post-splenectomy pulmonary hypertension and effects of its target therapy, and improve the diagnosis and treatment of the disease. Methods: Clinical data of 18 patients with post-splenectomy pulmonary hypertension admitted to Fuwai Hospital from October 2006 to March 2017 were systematically reviewed and analyzed. Results: Among the 18 patients with a mean age of (41±11) years old, 11 were women and 7 were men. The interval between splenectomy and the diagnosis of pulmonary hypertension was (11±6) years. Shortness of breath (14/18) and chest distress (12/18) were the most common clinical manifestations. Nine patients were in World Health Organization functional class (WHO-FC) Ⅲ-Ⅳ, and two patients were combined with pulmonary embolism. According to the cause of splenectomy, the pulmonary hypertension patients were divided into hepatocirrhosis portal hypertension group (10/18) and non-hepatocirrhosis portal hypertension group (8/18). In hepatocirrhosis portal hypertension group, patients were combined with chronic liver abnormalities presentation, and no pulmonary embolism was found in these patients. Cardiac output and cardiac index were significantly higher (P=0.007 and 0.011, respectively) and pulmonary vascular resistance was significantly lower (P=0.013) in hepatocirrhosis portal hypertension group as compared with non-hepatocirrhosis portal hypertension group. There was no difference in WHO-FC and mean pulmonary arterial pressure between two groups (P=0.448 and 0.379, respectively). After 3 months of target treatment in 8 patients, WHO-FC of 3 patients improved, systolic pulmonary artery measured by ultrasonic cardiogram was significantly decreased[(84±10) vs (71±12) mmHg(1 mmHg=0.133 kPa), P=0.005]and right ventricular end diastolic diameter/left ventricular end diastolic diameter was significantly reduced[(0.78±0.17) vs (0.62±0.16), P=0.010]compared to the baseline. The level of NT-proBNP also tended to be decreased, although not to a significant extent. Conclusions: Post splenectomy pulmonary hypertension has various clinical features. Post splenectomy pulmonary hypertension resulted from hepatocirrhosis portal hypertension has better hemodynamics. Target treatment is effective for the patients with post splenectomy pulmonary hypertension.

Gene expression profiling reveals candidate genes related to residual feed intake in duodenum of laying ducks

Feed represents two-thirds of the total costs of poultry production, especially in developing countries. Improvement in feed efficiency would reduce the amount of feed required for production (growth or laying), the production cost, and the amount of nitrogenous waste. The most commonly used measures for feed efficiency are feed conversion ratio (FCR) and residual feed intake (RFI). As a more suitable indicator assessing feed efficiency, RFI is defined as the difference between observed and expected feed intake based on maintenance and growth or laying. However, the genetic and biological mechanisms regulating RFI are largely unknown. Identifying molecular mechanisms explaining divergence in RFI in laying ducks would lead to the development of early detection methods for the selection of more efficient breeding poultry. The objective of this study was to identify duodenum genes and pathways through transcriptional profiling in 2 extreme RFI phenotypes (HRFI and LRFI) of the duck population. Phenotypic aspects of feed efficiency showed that RFI was strongly positive with FCR and feed intake (FI). Transcriptomic analysis identified 35 differentially expressed genes between LRFI and HRFI ducks. These genes play an important role in metabolism, digestibility, secretion, and innate immunity including (), (), (), β (), and (). These results improve our knowledge of the biological basis underlying RFI, which would be useful for further investigations of key candidate genes for RFI and for the development of biomarkers.

Calcium signaling involved in bovine herpesvirus 1 replication in MDBK cells

Calcium is one of the most prominent second messengers in eukaryotic cells. The involvement of calcium signaling in bovine herpesvirus 1 (BoHV-1) replication was not yet reported. In this study, we revealed that the L-type Ca2+ calcium channel blocker, Verapamil and store-operated calcium channel blocker, 2-aminoethyl diphenylborinate (2-APB) inhibited BoHV-1 replication in MDBK cells at the post-entry stages, and the Na+/Ca²+ exchanger inhibitor, N-arachidonoyl glycine exchanger (NAGly) interfered with the viral entry process. NAGly also effected the phosphorylation of PLCγ-1 at Ser1248, which corroborated our previous findings, that PLCγ-1 is important for BoHV-1 entry. Collectively, these results suggest that diverse calcium channels are employed by BoHV-1 for efficient replication.

Use of a microvascular coupler device for end-to-side venous anastomosis in oral and maxillofacial reconstruction

The aim of this study was to compare the use of a microvascular coupler device (MCD) for end-to-side venous anastomosis (ETS group) and phleboplasties combined with MCD for end-to-end venous anastomosis (ETE group) in free tissue transfer for oral and maxillofacial reconstruction, with regard to the anastomosis time and occurrence of postoperative vascular crisis. The ETS group included 22 patients and the ETE group included 40 patients. Patient demographic data, anastomotic time, coupler size, microvascular complications, and flap survival rates were collected and analyzed. In the ETS group, the most suitable donor vessel size was greater than 2mm, varying from 2mm to 4mm. The average anastomosis time was 3.35±0.89min in the ETS group and 7.80±2.93min in the ETE group; the difference between the groups was statistically significant (p<0.0001). There were no statistically significant differences in complications or outcomes between the two groups. The ETS venous anastomosis with MCD technique is a better choice for anastomosis when the donor vessel size is greater than 2mm. In those cases with mismatched veins, ETS venous anastomosis with MCD could significantly reduce the anastomosis time compared to ETE venous anastomosis with MCD after phleboplasties.

Calhm2 governs astrocytic ATP releasing in the development of depression-like behaviors

Extracellular ATP is a widespread cell-to-cell signaling molecule in the brain, where it functions as a neuromodulator by activating glia and neurons. Although ATP exerts multiple effects on synaptic plasticity and neuro-glia interactions, as well as in mood disorders, the source and regulation of ATP release remain to be elaborated. Here, we define Calhm2 as an ATP-releasing channel protein based on in vitro and in vivo models. Conventional knockout and conditional astrocyte knockout of Calhm2 both lead to significantly reduced ATP concentrations, loss of hippocampal spine number, neural dysfunction and depression-like behaviors in mice, which can be significantly rescued by ATP replenishment. Our findings identify Calhm2 as a critical ATP-releasing channel that modulates neural activity and as a potential risk factor of depression.

Role of miR-449a in the Activation and Metabolism of CD4+ T Cells

BACKGROUND

Acute rejection is a significant challenge after organ transplantation. The CD4⁺ T-cell‒mediated immune response plays an important role in acute transplant rejection. It was also found that miR-449a microRNA regulates the alloimmune response in a model of heart transplantation in mice. Our goal was to determine the role of miR-449a in the regulation of CD4⁺ T cells.

METHODS

We examined miR-449a expression in peripheral blood mononuclear cells (PBMCs) and graft-infiltrating lymphocytes (GILs) between syngeneic transplant and allogeneic transplant groups on day 7 post‒heart transplantation. We also examined miR-449a expression in CD4⁺ T-cell activation and mixed-lymphocyte reactions (MLRs) in vitro. To evaluate the effect of miR-449a on CD4⁺ T-cell metabolism, we analyzed key metabolic parameters using XFp extracellular flux analyses.

RESULTS

Our in vivo heart transplant models showed that the expression of miR-449a in PBMCs and in GILs significantly increased in the allogeneic groups in comparison to the syngeneic groups (P < .01). Furthermore, in vitro analysis confirmed that the expression of miR-449a was significantly elevated in activated CD4⁺ T cells. Reduction of miR-449a expression in CD4⁺ T cells decreased the mitochondrial respiration in the same CD4⁺ T cells.

CONCLUSION

Our results reveal that miR-449a microRNA was elevated in allogeneic heart allografts. This correlated with an increased miR-449a expression in activated CD4⁺ T cells. Inhibition of miR-449a in activated CD4⁺ T cells coincided with reduced mitochondrial respiration, suggesting that miR-449a influences CD4⁺ T-cell activation during the alloimmune response by regulating metabolic status.

Magnon Valve Effect between Two Magnetic Insulators

The key physics of the spin valve involves spin-polarized conduction electrons propagating between two magnetic layers such that the device conductance is controlled by the relative magnetization orientation of two magnetic layers. Here, we report the effect of a magnon valve which is made of two ferromagnetic insulators (YIG) separated by a nonmagnetic spacer layer (Au). When a thermal gradient is applied perpendicular to the layers, the inverse spin Hall voltage output detected by a Pt bar placed on top of the magnon valve depends on the relative orientation of the magnetization of two YIG layers, indicating the magnon current induced by the spin Seebeck effect at one layer affects the magnon current in the other layer separated by Au. We interpret the magnon valve effect by the angular momentum conversion and propagation between magnons in two YIG layers and conduction electrons in the Au layer. The temperature dependence of the magnon valve ratio shows approximately a power law, supporting the above magnon-electron spin conversion mechanism. This work opens a new class of valve structures beyond the conventional spin valves.

IL6 derived from cancer-associated fibroblasts promotes chemoresistance via CXCR7 in esophageal squamous cell carcinoma

Various factors and cellular components in the tumor microenvironment are key drivers associated with drug resistance in many cancers. Here, we analyzed the factors and molecular mechanisms involved in chemoresistance in patients with esophageal squamous cell carcinoma (ESCC). We found that interleukin 6 (IL6) derived mainly from cancer-associated fibroblasts played the most important role in chemoresistance by upregulating C-X-C motif chemokine receptor 7 (CXCR7) expression through signal transducer and activator of transcription 3/nuclear factor-κB pathway. CXCR7 knockdown resulted in the inhibition of IL6-induced proliferation and chemoresistance. In addition, CXCR7 silencing significantly decreased gene expression associated with stemness, chemoresistance and epithelial-mesenchymal transition and suppressed the proliferation ability of ESCC cells in three-dimensional culture systems and angiogenesis assay. In clinical samples, ESCC patients with high expression of CXCR7 and IL6 presented a significantly worse overall survival and progression-free survival upon receiving cisplatin after operation. These results suggest that the IL6-CXCR7 axis may provide a promising target for the treatment of ESCC.

Developing novel species-specific DNA markers for PCR-based species identification of the Lactobacillus sakei group

Identification of members of the Lactobacillus sakei group (LSG) by common phenotypic and genotypic methods is generally inadequate and time-consuming. The objective of this study was to develop novel species-specific primers based on sequence-characterized amplified region (SCAR) markers using random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) analysis. Three species-specific fragments were gel-purified, cloned and sequenced after preliminary screening of 80 random primers. Accordingly, three pairs of primers Lcur-F/R, Lgram-F/R and Lsakei-F/R were designed based on single species-specific bands (281, 278 and 472 bp) that were obtained from Lactobacillus curvatus, Lactobacillus graminis and L. sakei, respectively. The specificities of these primer pairs were confirmed in 21 LSG strains and 31 nontarget Lactobacillus strains. In addition, the detection limits for each primer pair were approx. 10⁵ , 10⁴ and 10⁶ cells per gram of meat samples spiked with L. curvatus, L. graminis and L. sakei, respectively. In conclusion, we have successfully developed a rapid, accurate and effective PCR-based method for identification of species in the LSG.

SIGNIFICANCE AND IMPACT OF THE STUDY

Neither phenotypic nor the most commonly used genotypic method (16S rRNA gene sequencing) provides sufficient resolution for accurate identification of the Lactobacillus sakei group. A sequence-characterized amplified region method developed in this study provides a rapid, cost-effective way to detect the member of the L. sakei group in meat sample.

[Clinical application of submental artery perforator flap in oral and maxillofacial defect restoration after tumor resection]

Objective: To summarize the clinical anatomical features and surgical technique of the submental artery perforator flap (SMAPF), and to evaluate the outcome and value of the flap for oral cavity reconstruction after cancer ablation. Methods: A total of 56 patients with oral cancer were included in this study. The modified SMAPF excluded the anterior belly of the digastric muscle and submental fatty tissue. The primary sites of malignancy were buccal mucosa (n=24), tongue (n=21), mandibular gingiva (n=6), mouth floor (n=3), soft palate (n=2). Results: The flap size varied from 3 cm×5 cm to 5 cm×12 cm. Four flaps presented mild venous congestion, which was salvaged with conservative measures such as acupuncture and blood letting. Overall flap survival rate was 100%. The SMAPF with septocutaneous perforator was used in 49 cases and with musculocutaneous perforator in seven cases. External jugular vein and internal jugular vein provides venous drainage were applied in half cases respectively. All the patients showed a good recovery of tongue mobility and mouth opening with a follow-up of 3-41 months. Local recurrence was detected in one patient 4 months after operation. Conclusions: The SMAPF is a reliable flap for oral cavity reconstruction with outstanding functional and aesthetic outcomes.

[Application of virtual reality in surgical treatment of complex head and neck carcinoma]

Objective: To investigate the application of virtual reality technology in the preoperative evaluation of complex head and neck carcinoma and he value of virtual reality technology in surgical treatment of head and neck carcinoma. Methods: The image data of eight patients with complex head and neck carcinoma treated from December 2016 to May 2017 was acquired. The data were put into virtual reality system to built the three-dimensional anatomical model of carcinoma and to created the surgical scene. The process of surgery was stimulated by recognizing the relationship between tumor and surrounding important structures. Finally all patients were treated with surgery. And two typical cases were reported. Results: With the help of virtual reality, surgeons could adequately assess the condition of carcinoma and the security of operation and ensured the safety of operations. Conclusions: Virtual reality can provide the surgeons with the sensory experience in virtual surgery scenes and achieve the man-computer cooperation and stereoscopic assessment, which will ensure the safety of surgery. Virtual reality has a huge impact on guiding the traditional surgical procedure of head and neck carcinoma.

Characterization and transplantation of enteric neural crest cells from human induced pluripotent stem cells

The enteric nervous system (ENS) is recognized as a second brain because of its complexity and its largely autonomic control of bowel function. Recent progress in studying the interactions between the ENS and the central nervous system (CNS) has implicated alterations of the gut/brain axis as a possible mechanism in the pathophysiology of autism spectrum disorders (ASDs), Parkinson's disease (PD) and other human CNS disorders, whereas the underlying mechanisms are largely unknown because of the lack of good model systems. Human induced pluripotent stem cells (hiPSCs) have the ability to proliferate indefinitely and differentiate into cells of all three germ layers, thus making iPSCs an ideal source of cells for disease modelling and cell therapy. Here, hiPSCs were induced to differentiate into neural crest stem cells (NCSCs) efficiently. When co-cultured with smooth muscle layers of ganglionic gut tissue, the NCSCs differentiated into different subtypes of mature enteric-like neurons expressing nitric oxide synthase (nNOS), vasoactive intestinal polypeptide (VIP), choline acetyltransferase (ChAT) or calretinin with typical electrophysiological characteristics of functional neurons. Furthermore, when they were transplanted into aneural or aganglionic chick, mouse or human gut tissues in ovo, in vitro or in vivo, hiPSC-derived NCSCs showed extensive migration and neural differentiation capacity, generating neurons and glial cells that expressed phenotypic markers characteristic of the enteric nervous system. Our results indicate that enteric NCSCs derived from hiPSCs supply a powerful tool for studying the pathogenesis of gastrointestinal disorders and brain/gut dysfunction and represent a potentially ideal cell source for enteric neural transplantation treatments.

A quantitative property-property relationship for the internal diffusion coefficients of organic compounds in solid materials

Indoor releases of organic chemicals encapsulated in solid materials are major contributors to human exposures and are directly related to the internal diffusion coefficient in solid materials. Existing correlations to estimate the diffusion coefficient are only valid for a limited number of chemical-material combinations. This paper develops and evaluates a quantitative property-property relationship (QPPR) to predict diffusion coefficients for a wide range of organic chemicals and materials. We first compiled a training dataset of 1103 measured diffusion coefficients for 158 chemicals in 32 consolidated material types. Following a detailed analysis of the temperature influence, we developed a multiple linear regression model to predict diffusion coefficients as a function of chemical molecular weight (MW), temperature, and material type (adjusted R² of .93). The internal validations showed the model to be robust, stable and not a result of chance correlation. The external validation against two separate prediction datasets demonstrated the model has good predicting ability within its applicability domain (Rext2>.8), namely MW between 30 and 1178 g/mol and temperature between 4 and 180°C. By covering a much wider range of organic chemicals and materials, this QPPR facilitates high-throughput estimates of human exposures for chemicals encapsulated in solid materials.

Nanodiamonds as pH-switchable oxidation and reduction catalysts with enzyme-like activities for immunoassay and antioxidant applications

Nanodiamonds (NDs) have recently become a focus of interest from the viewpoints of both science and technology. Their intriguing properties make them suitable as biologically active substrates, in biosensor applications as well as diagnostic and therapeutic biomedical imaging probes. Here, we demonstrate that NDs, as oxidation and reduction catalysts, possess intrinsic enzyme mimetic properties of oxidase, peroxidase and catalase, and these behaviors can be switched by modulating the pH value. NDs not only catalyze the reduction of oxygen (O₂) and hydrogen peroxide (H₂O₂) at acidic pH, but also catalyze the dismutation decomposition of H₂O₂ to produce O₂ at alkaline pH. It was proposed that the molecular mechanism of their peroxidase-like activity is electron-transfer acceleration, the source of which is likely derived from oxygen containing functional groups on their surface. Based on the color reaction, a nanodiamond-based enzyme linked immunosorbent assay (ELISA) was established for the detection of immunoglobulin G (IgG). Surprisingly, NDs display an excellent antioxidant activity due to the protective effect against H₂O₂-induced cellular oxidative damage. These findings make NDs a promising enzyme mimetic candidate and expand their applications in biocatalysis, bioassays and nano-biomedicine.

Beneficial effect of botulinum toxin A on secondary ischaemic injury of skin flaps in rats

Botulinum toxin A (BTX-A) protects against primary ischaemia of skin flaps, but its effect on secondary ischaemia is unknown. We induced secondary arterial or venous ischaemia in skin flaps of 32 Wistar rats, and tested the effectiveness of BTX injected subcutaneously 12hours before the flap was raised. The animals were divided into two groups of 16 (arterial or venous). Eight animals in each group were then treated with saline 1ml (control), and eight with BTX-A 5 IU (treatment). Ischaemia and necrosis were assessed after five days. There was no significant difference in necrosis between the two treatments in either group, but the amount of ischaemia did differ significantly (p=0.031 in the artetial ishcemia and p=0.015 in the venous ischemia group). BTX helped to salvage poor reperfusion in secondary ischaemia of skin flaps.

Genetic mapping using 1.4M SNP array refined loci for fatty acid composition traits in Chinese Erhualian and Bamaxiang pigs

Chinese indigenous pigs display marked genetic and phenotypic differences compared with western commercial pigs. In this study, we tested the association between 660K SNPs and longissimus muscle fatty acid composition traits in Chinese Erhualian (n = 331) and Bamaxiang (n = 315) pigs based on a customized 1.4 million SNP array. We identified a total of 64 significant associations for 20 fatty acid composition traits at the p-value threshold of 1 × 10^-6 among which 42 associations in low linkage disequilibrium (r²  < .2) with previously reported loci were considered novel. We substantially improved the strength and precision of the associations at four previously detected loci near FADS2, ELOVL7, ELOVL6 and FASN genes, facilitating follow-up candidate gene studies. Moreover, we also identified loci near ABCD2, ACSBG1, ELOVL5, HPGDS, DAGT2, ACAD10 and ACSL1 genes with function relevant to metabolism of fatty acids. In this study, valuable genetic variants and candidate genes associated with fatty acid composition traits were identified in Erhualian and Bamaxiang pigs. Some identified loci could be used to improve pork nutrition in pig breeding practice. Using the SNP array with higher marker density and less ascertainment bias improved QTL detection power and precision in Chinese indigenous pigs.

Vertical platysma myocutaneous flap reconstruction for oral defects using three different incision designs: experience with 68 cases

This study evaluated the effects of three different incision designs for the vertical platysma myocutaneous flap (VPMF): apron, MacFee, and T-shaped. This flap was used for the reconstruction of intraoral defects following cancer ablation in selected patients. Sixty-eight cases of VPMF reconstruction were assessed: the apron incision was used in 28, MacFee incision in 22, and T-shaped incision in 18. With regard to postoperative outcomes, there were 26 cases of flap survival and two of partial necrosis with the apron incision; 20 of survival and two of partial necrosis with the MacFee incision; 15 of survival and three of partial necrosis with the T-shaped incision. Success rates were 92.9%, 90.9% and 83.3%, respectively, for VPMF with the apron, MacFee, and T-shaped incisions. A wound healing disturbance in the neck was seen in three cases of VPMF with the apron incision and one case with the MacFee incision. The MacFee incision had the best aesthetic effect, and the postoperative neck scar was more obvious for the T-shaped incision. It is recommended that VPMF with the MacFee or apron incision be used for the reconstruction of larger buccal mucosa and floor of the mouth defects, while VPMF with the T-shaped incision should be used for smaller intraoral defects, especially tongue defects of the lateral surface.

Mucosa-associated microbiota signature in colorectal cancer

The aim of this study was to explore the gut microbiota profiles of colorectal cancer (CRC) patients and to examine the relationship between gut microbiota and other key molecular factors involved in CRC tumorigenesis. In this study, a 16S rDNA sequencing platform was used to identify possible differences in the microbiota signature between CRC and adjacent normal mucosal tissue. Differences in the microbiota composition in different anatomical colorectal tumor sites and their potential association with KRAS mutation were also explored. In this study, the number of Firmicutes and Actinobacteria decreased, while the number of Fusobacteria increased in the gut of CRC patients. In addition, at the genus level, Fusobacterium was identified as the key contributor to CRC tumorigenesis. In addition, a different distribution of gut microbiota in ascending and descending colon cancer samples was observed. Lipopolysaccharide biosynthesis-associated microbial genes were enriched in tumor tissues. Our study suggests that specific mucosa-associated microbiota signature and function are significantly changed in the gut of CRC patients, which may provide insight into the progression of CRC. These findings could also be of value in the creation of new prevention and treatment strategies for this type of cancer.

Physicochemical properties and cytotoxicity of an experimental resin-based pulp capping material containing the quaternary ammonium salt and Portland cement

AIM

To evaluate in vitro the physicochemical properties, cytotoxicity and calcium phosphate nucleation of an experimental light-curable pulp capping material composed of a resin with antibacterial monomer (MAE-DB) and Portland cement (PC).

METHODOLOGY

The experimental material was prepared by mixing PC with a resin containing MAE-DB at a 2 : 1 ratio. Cured pure resin containing MAE-DB served as control resin. ProRoot MTA and Dycal served as commercial controls. The depth of cure, degree of monomer conversion, water absorption and solubility of dry samples, calcium release, alkalinizing activity, calcium phosphate nucleation and the cytotoxicity of materials were evaluated. Statistical analysis was carried out using anova followed by Tukey's HSD test (equal variance assumed) or Tamhane test (equal variance not assumed) and independent-samples t-tests.

RESULTS

The experimental material had a cure depth of 1.19 mm, and the mean degree of monomer conversion was 70.93% immediately post-cure and 88.75% at 24 h post-cure. The water absorption of the experimental material was between those of MTA and Dycal, and its solubility was significantly less (P < 0.05) than that of Dycal and higher than that of MTA. The experimental material exhibited continuous calcium release and an alkalinizing power between those of MTA and Dycal throughout the test period. Freshly set experimental material, control resin and all 24-h set materials had acceptable cytotoxicity. The experimental material, MTA and Dycal all exhibited the formation of apatite precipitates after immersion in phosphate-buffered saline.

CONCLUSIONS

The experimental material possessed adequate physicochemical properties, low cytotoxicity and good calcium phosphate nucleation.