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Vital pulp therapy(VPT)is an important pathway to preserve and maintain pulp tissue in a healthy state. VPT has been improved recently as the new progress achieved in pathobiology, bioactive materials and clinical research. The present review summarizes the clinical outcomes and prognostic factors of VPT, including direct pulp capping, partial pulpotomy and full pulpotomy in mature permanent teeth with carious pulp exposure, and briefly introduces the new progress in this field.保存牙髓活力、维持牙髓功能、尽可能保留患牙的微创治疗理念是当代成熟恒牙牙髓治疗的重要发展趋势。本文基于最新研究，归纳龋源性露髓的成熟恒牙活髓保存治疗的临床疗效及其影响因素，简要介绍相关研究的新进展，以期为临床开展活髓保存治疗及今后该领域的发展提供参考。.

OBJECTIVE: To investigate the effects of phytic acid derived bioactive P(2)O(5)-SiO(2)-CaO gel-glasses (PSC) on the proliferation, differentiation and angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro. METHODS: HUVECs were cultured in PSC extracts, which were prepared with endothelial cell medium (ECM) at a gradient concentration of 0.01, 0.1, 1 and 2 g/L. Cells cultured in ECM were used as the control. The effect of PSC on HUVECs proliferation was assessed on the 1st, 3rd, 5th, 7th and 10th days with (4, 5-dimethylthiazol-2-yl) 2, 5-diphenyltetrazolium bromide assay (MTT), and the optimum PSC concentration for HUVECs proliferation was used in the following experiments. The subsequent experiments were divided into two groups. The experimental group used PSC extracts to culture HUVECs (PSC group) and the control group used ECM to culture HUVECs (ECM group). Gene expression of angiogenic factors, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), was detected on the 2nd, 4th and 7th days by real-time reverse transcription-polymerase chain reaction (real-time RT-PCR). The morphology and number of tubules formation were observed at the 4th and 10th hours. Image J software was used for counting and quantitative analysis. RESULTS: The results of MTT assay showed that 0.1 g/L PSC group had the most significant effect on promoting HUVECs proliferation. The optical density values of 0.1 g/L PSC group on the 5th and 7th days were significantly higher than those of the other PSC groups and the control group (P < 0.05). The result of real-time RT-PCR showed that 0.1 g/L PSC extract up-regulated the mRNA expression of VEGF and bFGF significantly (P < 0.05). On the 4th day, the gene expressions of VEGF and bFGF in PSC group were 1.59 and 1.45 times higher than those in ECM group respectively, and on the 7th day, the gene levels of VEGF and bFGF in PSC group were 1.98 and 1.37 times higher than those in ECM group respectively. The tubule formation assay showed that the maturity and density of the tubules in 0.1 g/L PSC group was much better than that in the ECM group at the 10th hour. The quantitative analysis by Image J indicated that the tubules number in PSC group (29.63±2.29) was higher than in the ECM group (20.13±2.36), with statistical significance (P < 0.05). CONCLUSION: PSC showed significant promoting effects on HUVECs' proliferation, differentiation and angiogenesis in vitro.

Small nucleolus RNA Host Gene 8 (SNHG8) belongs to a subgroup of long non-coding RNAs. SNHG8 is upregulated in many cancers, such as gastric cancer, liver cancer, and esophageal squamous cell cancer. However, whether SNHG8 is abnormally expressed in breast cancer and its biological functions remain unclear. Therefore, our research intended to determine the expression status of SNHG8 in breast cancer, explore the effects of SNHG8 on the development of breast cancer, and investigate the potential molecular mechanisms in cancer progression.The expression levels of SNHG8 were detected in tissue samples and cell lines via qRT-PCR. The effects of SNHG8 on viability of breast cancer cells were detected via CCK-8, EdU, transwell, and flow cytometry analyses.qRT-PCR results showed that the expression level of SNHG8 was significantly upregulated in tumor tissues and cell lines. Gene functional studies showed that the downregulation of the expression level of SNHG8 significantly inhibited the breast cancer cells migration and invasion, and induced apoptosis. Meanwhile, we found that SNHG8 served as an inhibitor of miR-634 in tumor tissues. SNHG8 may participate in the malignancy of breast cancer by sponging the miR-634 to increase the expression level of ZBTB20.The SNHG8-miR-634-ZBTB20 pathway may be a potential target for the treatment of breast cancers.

To investigate the physical and chemical properties of pulp capping materials based on bioactive glass (BG).Novel BG pulp capping materials were composed of powder and fluid. The powder was BG (82.36% SiO(1) Setting time: the initial and final setting time of BG-PB were (7.2±0.3) min and (12.7±0.9) min, respectively. And the initial and final setting time of BG-PB-SA was (7.5±0.3) min and (13.6±1.6) min. There was no significant difference between BG-PB and BG-PB-SA groups (P0.05). (2) Compressive strength: the compressive strength of BG-PB was (16.5±1.8) MPa at 1 day and (14.1±3.7) MPa at the end of 28 days. However, the compressive strength of BG-PB-SA was (26.6±6.3) MPa on day 1 and (21.6±5.6) MPa on day 28, which was significantly higher than that of BG-PB (P0.05). (3) pH: the pH of BG pulp capping materials' bulk immersed in simulated body fluid (SBF) went up to 8.06, and the highest pH of MTA was 8.47. Significant difference was observed between the BG pulp capping materials and MTA (P0.05). (4) Sealing ability: the optical density (D) in positive control group was significantly higher than ln BG-PB, BG-PB-SA and MTA groups (P0.05). And BG-PB and BG-PB-SA showed the similar favorable sealing ability with MTA, and no significant difference was observed among the three groups (P0.05).The novel BG pulp capping materials showed good physical properties, especially BG's setting time was short; BG pulp capping materials are promising.

To construct mesoporous nano-bioactive glass (MNBG) microspheres load-release minocycline as an antibacterial drug delivery system.Sol-gel method was used to synthesze MNBG microspheres as drug carrier. The MNBG consisted of SiO2, CaO, and P2O5. According to the content of silicon, MNBG microspheres were divided into four groups (60S, 70S, 80S and 90S). Scanning electron microscopy (SEM) was used to observe the surface characteristic and particle size of MNBG; Nitrogen adsorption-desorption experiment was performed to calculate the MNBG's specific surface area and the pore sizes; The Fourier transform infrared spectrum (FT-IR) and the thermogravimetric analysis were conducted to calculate the loading efficiencies of minocycline hydrochloride; UV spectrophotometric was used to determine the cumulative release of minocycline from drug-loaded particles in PBS solution within 21 d. Agar diffusion test (ADT) was performed to evaluate the antibacterial properties on Enterococcus faecalis. The inhibition zone was observed and the diameter was measured.The MNBG microspheres had good dispersion, large surface area, and even particle size. The pore sizes ranged from 4.77 nm to 7.33 nm. The loading experiment results showed that the minocycline hydrochloride loading efficiency of MNBG was related to the pore size of the microspheres. Among 60S, 70S, 80S and 90S, 60S MNBG had the highest loading efficiency of 16.33% due to its high calcium content and large pore sizes. A slow minocycline release rate from MNBG particles in PBS solution until d 21 was observed. It was showed that a burst release of 28% of the total drug for the first 24 h. A cumulative release of 35% was found, and the final concentration of minocycline maintained at about 47 mg/L. ADT showed that mino-MNBG had inhibitory effect on the growth of Enterococcus faecalis. 1 g/L minocycline, 1 g/L mino-MNBG, and 0.1 g/L minocycline presented inhibition zone, however, PBS and 1 g/L MNBG didn't. The diameter of the inhibition zone of minocycline groups was significant larger than that of mino-MNBG group (P0.05), which was also significant larger than those of PBS and MNBG groups (P0.05). It showed that mino-MNBG drug delivery system had antibacterial properties on Enterococcus faecalis.The 60S MNBG that can effectively load and release minocycline may be an ideal drug carrier.

To compare the osteogenic effects of a nano-sized 58S bioactive glass (nano-58S BG) and a traditional 45S5 bioactive glass(45S5 BG) in penetrating parietal critical bone defects.Critical bone defect with 9 mm diameter was created in the parietal bone of New Zealand rabbits. The bone defects were then filled with either nano-58S BG, or 45S5 BG, or nothing but the newly-formed blood clot as the blank control at random. For histological observation, specimens were gained 4 and 8 weeks after the surgery, sectioned and stained by HE. The amount of collagen type I was observed with Picric-Sirius Red staining through polarimetry. To observe the new bone formation with fluorescence under the laser confocal microscope, we injected fluorescent markers 14, 28, and 42 days after the surgery. The markers were tetracycline hydrochloride, alizarin red and calcin individually in chronological order. Image J software was used to quantify the bone regeneration.HE staining showed that BG particulates were integrated with the surrounding tissue without any inflammatory cells infiltration 4 weeks after surgery. New bone regeneration was observed both from the border and in the center of the defects in both BG groups. No bone regeneration in defect center was observed in control group. At the end of 8 weeks, there was more bone regeneration in nano-58S group compared with 45S5 group and control group. The structure of the new bone in BG groups was hollow, which was similar to the natural normal parietal bone. No hollow structure was observed in the new bone of control group. Picric-sirius Red polarimetry showed that more amount of collagen type I was found in nano-58S group than in either 45S5 or control group. The fluorescent observation of the hard tissue slices at the end of 8 weeks showed statistically larger scope and faster new bone formation in nano-58S group with (29.4±4.48) μm thickness from 4-6 weeks and (35.3±3.74) μm from 6-8 weeks compared with 45S5 group [(13.43±3.44) μm and (17.64±4.13) μm] and control group [(5.88±2.92) μm and (6.07±3.02) μm, P0.01].Compared with the traditional 45S5 bioactive glass, 58S nano-sized bioactive glass showed better osteogenic effect in bone regeneration in parietal bones of rabbits.

To investigate the proliferation, odontogenic differentiation and mineralization of human dental pulp cells (HDPCs) on bioactive glass(BG) and extracted dentin proteins(EDP).Primary HDPCs were isolated from third molars by enzyme digestion and were cultured in Dulbecco's minimum essential medium (DMEM). Then the 4th generation of HDPCs was cultured with DMEM, which contained BG-EDP, BG, and EDP, respectively. Meanwhile HDPCs were cultured in DMEM as control group. Proliferation of HDPCs was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) colorimetric assay. Odontogenic differentiation was determined by alkaline phosphatase (ALP) activity assay and real-time PCR. Mineralization was investigated by Alizarin red staining and cetylpyridinium chloride (CPC) assay.The proliferation of HDPCs was increased significantly in BG-EDP group on 3,7,and 9 d (optical density value: 1.36±0.06, 2.52±0.20, 2.72±0.29) compared with BG (optical density value: 1.20±0.26, 2.33±0.26, 2.50±0.30), EDP(optical density value: 1.13±0.15, 2.10±0.13, 2.38±0.22) and control group (optical density value: 0.84±0.17, 1.84±0.18, 1.95±0.19), P0.05. After 7 days, ALP activity of BG-EDP group had no statistical difference compared with EDP group and control group; the expression of odontogenic differentiation genes (DSPP, DMP-1) showed no difference among all the groups(P0.05). After 14 days, ALP activity of BG-EDP group (56.67±1.83) was significantly upregulated compared with EDP group (41.98±9.71) and control group (30.82±6.70), P0.05, but had no statistical difference compared with BG group (56.29±6.20), P0.05; DSPP gene expression was upregulated significantly in BG-EDP group (5.79±1.94) compared with the other groups (P0.05); DMP-1 gene expression of BG-EDP group (3.87±1.87) increased but had no statistical difference compared with the other groups (P0.05). The alizarin red staining showed more mineral nodules in BG-EDP group, the cetylpyridinium chloride semi-quantification presented higher calcification in BG-EDP group (0.27±0.01) compared with the other groups (P0.05).Compared with either BG or EDP, BG-EDP significantly promotes the proliferation, odontogenic differentiation and mineralization of HDPCs.

Positive effects of bioactive glass (BG) on proliferation, mineralization, and differentiation of human dental pulp cells (hDPCs) was already verified in various former studies. The Arg-Gly-Asp-Ser sequence (RGDS) was confirmed of affecting cell adhesion. Before further investigation, the objective of this study is to investigate whether RGDS can affect the effects of BG on the adhesion, proliferation and mineralization of hDPCs.hDPCs were harvested from third molars of 18-25-year-old individuals after informed consent. Enzyme digestion technique was used. The 4th to 6th generation of hDPCs were used for all experiments. The cells of the experimental groups were cultured in Dulbecco minimum essential medium (DMEM) containing ionic dissolution products of BG and RGDS of several concentrations (12.5 mg/L, 25.0 mg/L, 50.0 mg/L, 100.0 mg/L, 200.0 mg/L). DMEM containing ionic dissolution products of BG without RGDS was used for cell culture as control group. Cell adhesion was tested 4 h after cell seeding by MTT assay. Cell proliferation was examined at 1, 3, 5, 7, and 9 d after cell seeding by MTT assay. Cell mineralization was investigated on days 14 and 28 by alizarin red staining. After being stained and dried, mineralized nodules were dissolved by cetylpyridinium chloride (CPC) for semi-quantitative test. Results were statistically analyzed by one way ANOVA, SPSS (version 19.0) and P0.05 was considered to be significant.Cell adhesion in BG group showed no difference from that in DMEM group. Compared with BG group, hDPCs in BG+RGDS groups suggested weaker cell adhesion.When the concentration of RGDS increased, the adhered cell number decreased. hDPCs cultured with BG and RGDS showed lower proliferation activity in the early stage, while no significant difference was observed after 3 d. BG group promoted the mineralization of hDPCs compared with positive control group, negative control group and RGDS group. No significant difference was observed between BG+RGDS group and BG group or between RGDS group and positive control group.BG promotes proliferation and mineralization without affecting cell adhesion of hDPCs. Unbounded RGDS inhibits cell adhesion, but has no influence on the positive effects of BG on the proliferation and mineralization of hDPCs.

To analyze the accuracy of the digital imaging fiber optic transillumination (DIFOTI) on diagnosis of caries lesions depth using DIAGNOcam system.This experiment adopted self-matching design. Seventy-four extracted teeth (molar: sixty-six, premolar: eight) with one caries lesions in proximity which were not damaged in surface marginal ridge were selected. Dental calculus and dental stains were removed from the extracted teeth for standby application. A sign was marked in the middle of the occlusal surface edge at the side of decay. Then the teeth were fixed in the standard model of dentition and cavities were adjacent with the sound tooth surface. Sticky wax was applied to seal the level of 2 mm beyond cemento-enamel junction (CEJ) in the direction of occlusion and interproximal space to imitate gingival margin and gingival papilla. The standard models of dentition was seated in imitation head mold. The lesions depth degree was looked into and checked with DIAGNOcam system. Besides, the pictures on the occlusal surfaces were recorded and saved. The sign above could be seen on the picture. The measuring tool in DIAGNOcam system was used to measure the depth of the caries from the sign (as starting point) to the deepest point of caries in the pictures and its length was recorded for a. The line a was lengthened to the contralateral edge of occlusal surface in the photo and the length was recorded for b. A line from the marked point on the occlusal surface edge of the extracted teeth was draw parallel to the line b on the corresponding photo and its length was recorded for c. The depth of the cavities on the projected images was recorded for d, and calculated d/a=c/b (digital optical fiber measured decay depth/caries damage depth of the image=actual tooth width/tooth width of the image), and d=c/b×a inferred. At last, the teeth were taken out from the standard model dentition. The decay of the tooth was removed completely. The actual depth of the cavity was recorded for D. The difference between d and D was recorded for Δd. The software of SPSS 20.0 was used to test the consistency of the results, and the MedCalc 14.8.1.0 software was used for Bland-Altman analysis.The intraclass correlation coefficient (ICC) between d and D was 0.951 (ICC75%), P=0.263. There was a function relationship y=0.23+0.91x between d(x) and D(y). Bland-Altman analysis method showed that the mean of Δd (Δdmean) was 0.05 mm, the standard deviation of Δd (ΔdSD)=0.308, and the 95% confidence interval was (-0.55 to 0.65). The amplitude of difference was clinically acceptable. So the consistency of the two measurement modes was high.There was no significant difference between the depth of caries lesions checked with DIAGNOcam system and the depth of the actual cavity, and the consistency was very good. The vitro study suggests that the DIAGNOcam system may be used to assess the depth of caries cavity as a useful tool in diagnosis and treatment.

To fabricate a new solid base with high efficiency in the adsorption of CO

Cancer stem cells play a major role in developing hepatocellular carcinoma (HCC), and they are not well identified in in vivo settings. Also, their occurrence and specificity are not well defined in different pathological stages of the tumor. CD133 is a cancer stem cell specific marker which also lacks to specify all the cancer stem cell population and similarly different markers fails to identify cancer stem cells. To overcome this multi marker helps to identify the cancer stem cells with maximum coverage and aids to understand their expression in different pathological stages of HCC.In this study, we compared the expression of CD133 along with TBRII and ELF using Immunohistochemistry and western blotting technique that probably helps to reveal the nature of cancer stem cells in different pathological stages of HCC.We initially develop CD133 induced tumorigenicity mice with HCC and compared their tissue morphology using histology. The histological data reveal that as tumor progress, the cell proliferative ability increase together with a large nucleus. The Immunohistochemical data against CD133 shows a prominent increase in their expression as tumor progress, but we found out that the tumor suppressor related proteins, TBRII and ELF shows increased expression in primary tumor stages to prevent tumor initiation, but neither of them shows prominent up-regulation in metastasis stages of the tumor.Our results conclude that the tumor suppressor proteins TBRII and ELF shows elevated expression pattern in the primary stage, but in advance stages its expression gets down-regulated and that fails to control metastasis stage.

To study the biological characteristics of new retrograde filling materials iRoot BP plus and iRoot FS.(1) The roots were cut into 3 mm in length, and the root canals were prepared to 1 mm in diameter, followed by being filled with iRoot BP plus, iRoot FS, or mineral trioxide aggregate (MTA). The specimens were immersed in simulated body fluid (SBF). The ability of mineralization in vitro was detected through three studies. First, the mineralization of specimens was analyzed through scanning electron microscope observations and energy dispersive X-ray spectrometer. Then, the pH of SBF was monitored using pH meter. (2) The extracts were gained by immersing blocks of iRoot BP plus, iRoot FS, and MTA (8 mm diameter and 2 mm height) into dulbecco's modified eagle medium (DMEM). The effects of the extracts on proliferation of MG63 cells were detected through MTT assay. The gene expression level of alkaline phosphatase (ALP) was analyzed by quantitative real-time PCR, and the expression of ALP activity was observed by ALP activity staining.(1) The formation of minerals could be observed on the surfaces of iRoot BP plus, iRoot FS, and MTA at the end of 24 h, and there were more amounts of apatite aggregated after 14 days. The values of Ca/P ratios of apatites were 1.43, 1.39, and 1.51, respectively. (2) The pH of SBF could be raised to 8.09±0.07, 7.91±0.06, and 8.11±0.06, respectively, significantly higher than the blank. (3) The extracts of iRoot BP plus, iRoot FS, and MTA of dilutions of 1:5 and 1:10 presented no effect of proliferation of MG63 cells. (4) iRoot BP plus and iRoot FS could significantly up-regulated the levels of ALP messenger RNA expression, while there was no obvious difference in ALP staining among the iRoot BP plus, iRoot FS, MTA, and the blank.The present study shows that iRoot has displayed good mineralization capability in vitro and capability to promote differentiation and mineralization of MG63 cells, inferring that iRoot may have good bioactivity.

Nanostructured ferritic oxide dispersion strengthened (ODS) alloys are promising materials for both high temperature creep properties and irradiation resistance. These alloys were produced by mechanical alloying (MA) which is a complex process and a number of process variables need to be controlled to achieve the desired properties. In this study, the effect of mechanical alloying and consolidation processes on the microstructure and properties of nanostructured ferritic ODS alloy were investigated. The powder mixtures were milled in Spex mill for different milling times (1 h, 3 h, 8 h, and 15 h). The effect of process control agents (PCAs) and ball to power ratio (BPR) were studied. Two-stage sintering and canning-HIP processes were introduced as new consolidation methods to produce ODS alloys with improved mechanical properties. The results showed that crystallite size during milling decrease with milling time and higher BRP has a significant influence on the rate of decrease of the crystallite size. The use of stearic acid as PCA led to fine, uniform and spherical particles during the ball milling. Additionally, the samples sintered at the elevated temperatures over long periods resulted in a reduction in porosity; however, the microstructure became coarser, accompanied by a decrease in the hardness. The canning-HIP technique can effectively minimize the content of oxygen and carbon impurities to achieve high relative density and high hardness.

The exoskeleton-type system is a brand new type of man—machine intelligent system. It fully combines human intelligence and machine power so that machine intelligence and human operator's power are both enhanced. Therefore, it achieves a high-level performance that neither could separately. This paper describes the basic exoskeleton concepts from biological system to man—machine intelligent systems. It is followed by an overview of the development history of exoskeleton-type systems and their two main applications in teleoperation and human power augmentation. Besides the key technologies in exoskeleton-type systems, the research is presented from several viewpoints of the biomechanical design, system structure modelling, cooperation and function allocation, control strategy, and safety evaluation.

A novel optical cable fault location method, which is based on Brillouin optical time domain reflectometer (BOTDR) and cable localized heating, is proposed and demonstrated. In the method, a BOTDR apparatus is used to measure the optical loss and strain distribution along the fiber in an optical cable, and a heating device is used to heat the cable at its certain local site. Actual experimental results make it clear that the proposed method works effectively without complicated calculation. By means of the new method, we have successfully located the optical cable fault in the 60 km optical fiber composite power cable from Shanghai to Shengshi, Zhejiang. A fault location accuracy of 1 meter was achieved. The fault location uncertainty of the new optical cable fault location method is at least one order of magnitude smaller than that of the traditional OTDR method.

A method for traffic light recognition in a miniature environment is proposed in this paper, which provides theoretical basis and technical support for the study in a general realistic environment. First, a source image is segmented to reduce the amount of calculation. Then colour space is converted and candidate regions of traffic lights are extracted. Afterwards morphological filtering and edge extraction are conducted, then circles detected by Hough transform. Finally, detection results are obtained by taking account of geometric features.

A systematical scheme effective to the defect assessment of reactor pressure vessels and pipes is proposed in the present paper. Theoretical fracture resistance curves for power law strain hardening materials are proposed, which are characterized by two fracture parameters, namely the fracture toughness J IC and the initial tearing modulus T C . The defect assessment method constructed upon the theoretical resistance curves is then referred to as the “Two Parameter Assessment Scheme” for ductile fracture processes, in which the tedious measurement on resistance curves is replaced by the tabulated data of J IC and T C . A blunting correction is advanced which enables the extension of the present methodology to pressure vessel steels of high toughness. The versatility of the two parameter assessment method is demonstrated by its four different representations, and its applicability is verified by measured burst pressure data of 6 model vessels. Approximate but analytical expressions for J integral pertinent to a variety of crack geometries are provided, whose accuracy satisfies the requirement of engineering assessment.

— A new approach to structural integrity assessment based on ductile fracture is explored in the present paper. A simplified, yet more convenient methodology than the conventional EPRI elastic-plastic fracture analysis is outlined which assesses the ductile fracture instability of structures by an intersection rather than a tangent construction. The J-equivalence principle of crack growth is employed for tearing instability determination of single edge cracked plates. An admissible stress curve method is established with a peak value indicating instability. This approach gives reasonable predictions concerning the burst pressure of pre-flawed pressure vessels. A theoretical J resistance curve, which is justified by experimental measurements for steels with relatively high yield strength, can be incorporated for a complete analytical characterization of the defect assessment procedure.

Intensified plaque acidogenicity in caries–prone subjects was reported many years ago, but emerging evidence has suggested that the relationship may not be as strong as once thought. We have now determined a range of acidogenicity variables in subjects having both caries prevalence and incidence data, and have included plaque mineral data in the analysis. pH measurements were made in 20 randomly selected subjects from a high–caries group (mean DMFS = 8.95) and 20 from a caries–free group of Beijing children aged 12 years participating in a caries prediction study. Subgroups with a 12–month DMFS increment ≥2 or = 0 were also formed from the two groups, respectively. Measurements were made with an iridium oxide electrode inserted between teeth 13/14, 23/24, 34/35 and 44/45, before and every 5 min for 30 min after rinsing with 10% sucrose, and the 4 resulting ‘Stephan curves’ averaged using a plaque pH analysis program. Supragingival plaque was collected from buccal and lingual smooth surfaces of posterior and upper anterior teeth and its acid extract analysed for Ca, P and F. Caries–free subjects (based on past experience) had a significantly higher maximum plaque pH and pH value after 30 min (reflecting a faster return to resting pH), a lower minimum enamel dissolution capacity of plaque and recorded less time below pH 7.0 than did high–caries subjects. No other differences were significant, including those of the principal acidogenic parameters ‘minimum pH attained after a sugar rinse’, ‘curve area below the critical pH of 5.5’ and ‘time below the critical pH’. Selection of the caries groups on the basis of both experience and incidence did not reveal significant differences in more parameters. Upper arch plaque was significantly more acidogenic than lower arch plaque, and there was a consistently strong association between upper and lower arch values in individuals. Ca, P and F in the subjects’ plaque had little or no influence on the principal acidogenic parameters. Our failure to find a relationship between caries prevalence or activity and these principal acidogenicity parameters may be related to differences between fissure and smooth surface plaque, temporal variations in acidogenicity and/or to use of F toothpaste during the 1–year observation period. These results support the view that factors such as the frequency of acidogenic episodes may be more important in caries progression than the degree of acidogenicity during any one episode.

To study the significance of monoclonal antibody SC3A expression in gastric carcinoma and precancerous lesions.Immunohistochemical staining and mucin histochemical staining were performed on paraffin-embedded sections from gastric benign and malignant lesions from 101 patients.SC3A positive rate was 80.3% (57/71) in lesions of gastric carcinoma. The expression of SC3A was not related to the classification, differentiation, metastasis and or survival rates. The positive rate of SC3A in cancers secreting acid mucin (90.2%) or sulphomucin (91.3%) was higher than that in cancers without acid mucin (20.0%) or sulphomucin (60.0%) (P0.01). The positive rate of sulphomucin was higher in cases of intestinal metaplasia with cancer (88.9%) than that of cases of intestinal metaplasia with a benign lesion (35.3%) (P0.01). Additionally, the positive rate of SC3A with sulphomucin in intestinal metaplasia (60.9%) was higher than that without sulphomucin (31.3%) (P0.05).SC3A monoclonal antibody might be helpful in the diagnosis of gastric cancer and the discernment of histogenesis.

To study the ultrastructural localization of five marker enzymes (ALPase, ACPase, G6Pase, TPPase and CCOase) in gastric cancer signet ring cells to demonstrate their biologic behaviors.Five marker enzymes were examined in signet ring cells of seven gastric cancer patients by ultrastructural enzyme cytochemical techniques.The number of corresponding organelles and the activities of marker enzymes, especially ACPase and TPPase, increased, leading to stronger mucus synthesis, secretion and digestion in gastric cancer signet ring cells. There was a lack of collagenous fibers in the stroma around the cancer nests.Signet ring cell carcinoma is very invasive with metastasis rates due to the secretion of proteolytic enzymes.

By using light and electron microscopic histochemical techniques, the activities and distributions of ALP isoenzymes in gastric cancers and benign gastric diseases were examined. The results showed: Nagao, Regan and Kasahara isoenzymes, which were not expressed in normal gastric mucosae and non-malignant lesions, may be considered as the tumor markers of gastric cancer. The epithelium of intestinal metaplasia exhibited intestinal-type ALP only, which was one of the markers of well-differentiated intestinal metaplasia. In the view-point of the gene expression of ALP isoenzymes, two mutation hypothesis and recessive-gene mutation hypothesis may be proper for gastric cancer.

Nine title compounds were synthesized as potential antimyocardial ischemic agents. After screening, some of these compounds were found to exhibit calcium-blocking activity. Among them, the antagonism of compound I6 (diethyl 4-(3-methoxy-4-[(2-hydroxy-3-isopropylamino)propoxy] phenyl)-1,4- dihydropyridine-3,5-dicarboxylates) was the most potent in the potassium- stimulated rabbit aortic strip. Compound I6 was subjected to further pharmacological assay, and it was shown to increase coronary flow and cardiac output of isolated rabbit heart, reduce myocardial oxygen consumption, decrease myocardial infarct size of rat, and increase the tolerance of mice to hypoxia.

In order to search for effective antimyocardial ischemic agents, fourteen new 3-[4-[(3-alkylamino-2-hydroxy)propoxy]phenyl(benzyl)]-substituted 4(3H)-quinazolinones (II) were synthesized. Substituted o-aminobenzoic acids used as the starting materials were allowed to react with acetic anhydride and then p-amino-phenol (method A), or with N-(4-hydroxyphenyl)formamide (method B), or with thionyl chloride and then N-(4-hydroxybenzyl)formamide (method C) to form 3-[(4-hydroxyphenyl(benzyl)]-substituted 4(3H)-quinazolinones (III). The intermediate III reacted with epichlorohydrin to form the epoxides (IV). The reaction of IV with an excess of isopropylamine or tert-butylamine in boiling chloroform gave the desired products. Of all the compounds synthesized, compounds II3-5 and II13 were found to increase the tolerance of mice to hypoxia. Further evaluation is in progress.