Subjective Evaluation of Denture Adhesives: A Multicenter Randomized Controlled Trial

INTRODUCTION

Many reports show that denture adhesives improve the retention and stability of dentures. However, few randomized controlled trials have examined the effects of denture adhesives.

OBJECTIVE

This 10-center randomized controlled trial with parallel groups involving 200 edentulous patients wearing complete dentures aimed to evaluate the effects of short-term use of cream and powder denture adhesives.

METHODS

Patients were allocated into 2 cream- and powder-type adhesive groups and 1 control group. Intervention groups were treated with the 2 adhesives (1 each), and the control group received saline solution. Adhesive or control was applied to the denture-mucosal surface for 4 d, and data at baseline and after day 4 of intervention (i.e., 8 meals) were obtained. Patient satisfaction was evaluated with a 100-mm visual analog scale. Oral health-related quality of life was measured with the Japanese version of the Oral Health Impact Profile for Edentulous Patients. Perceived chewing ability was evaluated by a questionnaire regarding ease of chewing and swallowing food. Between-group comparisons were performed with Kruskal-Wallis tests with the Mann-Whitney U test adjusted by Bonferroni correction. Within-group comparisons of pre- and postintervention measurements were performed with the Wilcoxon signed-rank test. Intention-to-treat analysis was also performed.

RESULTS

Between-group comparisons showed no significant differences for general satisfaction or Oral Health Impact Profile for Edentulous Patients. However, significant differences in satisfaction with various denture functions with cream- and powder-type adhesives were seen in pre- and postintervention comparisons (P < 0.05). Significant differences were also observed for perceived chewing ability of hard foods (P < 0.05).

CONCLUSION

These results suggest that although denture adhesives do not invariably improve denture function, they do affect subjective evaluations and possibly chewing of hard foods. Therefore, the effects of denture adhesive use are insufficient to resolve any fundamental dissatisfaction with dentures ( ClinicalTrials.gov NCT01712802 ).

KNOWLEDGE TRANSFER STATEMENT

The results of this study suggest that denture adhesives should be applied under certain conditions; however, an appropriate diagnosis is important before application. These practice-based data provide information to establish evidence-based guidelines for applying denture adhesives.

Dynamic behaviour of the soft palate during nasal positive pressure ventilation under anaesthesia and paralysis: comparison between patients with and without obstructive sleep-disordered breathing

BACKGROUND

Difficult mask ventilation is common and is known to be associated with sleep-disordered breathing (SDB). It is our hypothesis that the incidence of expiratory retropalatal (RP) airway closure (primary outcome) during nasal positive pressure ventilation (PPV) is more frequent in patients with SDB (apnea hypopnea index ≥5 h^-1) than non-SDB subjects.

METHODS

The severity of SDB was assessed before surgery using a portable sleep monitor. In anaesthetized and paralysed patients with (n=11) and without SDB (n=9), we observed the behaviour of the RP airway endoscopically during nasal PPV with the mouth closed and determined the dynamic RP closing pressure, which was defined as the highest airway pressure above which the RP airway closure was reversed. The static RP closing pressure was obtained during cessation of mechanical ventilation in patients with dynamic RP closure during nasal PPV.

RESULTS

The expiratory RP airway closure accompanied by expiratory flow limitation occurred more frequently in SDB patients (9/11, 82%) than in non-SDB subjects (2/9, 22%; exact logistic regression analysis: P=0.022, odds ratio 3.6, 95% confidence interval 1.1-15.4). Receiver operating characteristic curve analyses indicated AHI >10h^-1 and presence of habitual snoring as clinically useful predictors for the occurrence of RP closure during PPV. Dynamic RP closing pressure was greater than the static RP closing pressure by approximately 4-5 cm H₂O.

CONCLUSIONS

Valve-like dynamic RP closure that limits expiratory flow during nasal PPV occurs more frequently in SDB patients.

Inhibition of 12(S)-hydroxyeicosatetraenoic acid (12-HETE) production suppressed the intimal hyperplasia caused by poor-runoff conditions in the rabbit autologous vein grafts

The efficacy of OPC-29030, a newly developed inhibitor of 12(S)-hydroxyeicosatetraenoic acid (12-HETE) production, was evaluated on intimal hyperplasia of experimental autologous vein grafts in a distal poor-runoff model and a hyperlipidemic model in rabbits. First, rabbits were divided into two groups, the distal poor-runoff group (PR group) and the hyperlipidemic group (HL group). After 4 weeks preparing the PR model and the HL model, the femoral vein was implanted into the ipsilateral femoral artery. Then they were subdivided into two groups, depending on the diet provided; diet group with 0.1% OPC-29030 (OPC-29030 group) and normal diet group (control group). At 4 weeks, the grafts were harvested, and intimal hyperplasia of the graft was measured with an ocular cytometer. Intimal cell proliferation was determined by bromodeoxyuridine (BrdU) incorporation at 2 weeks after surgery. In addition, the effect of OPC-29030 on the proliferation or migration of rat aortic smooth muscle cells in culture was investigated. In the in vivo study in the PR group, the intimal hyperplasia and the plasma 12-HETE levels in the OPC-29030 group were significantly inhibited, compared with those of the control group. However, in the HL group, the intimal hyperplasia in both the OPC-29030 and control groups showed a remarkable degree of intimal hyperplasia. There was no significant difference between those two groups. Furthermore, there was no significant difference in the plasma 12-HETE levels in the HL group irrespective of the presence of OPC-29030. The BrdU labeling index at 2 weeks after grafting was significantly lower in the OPC-29030 group compared with that in the control group in the PR group. In the in vitro study, OPC-29030 did not inhibit smooth muscle cell proliferation; however, OPC-29030 inhibited the migration. These results demonstrate the efficacy of OPC-29030 in reducing the degree of intimal hyperplasia under PR conditions, but not under hyperlipidemic conditions. The mechanism of reducing the intimal hyperplasia may be that OPC-29030 inhibited 12-HETE production, which did not inhibit proliferation while inhibiting migration of the smooth muscle cell. These results suggested the possible involvement of 12-HETE with the intimal hyperplasia under PR conditions.

The effect of protein kinase C and its alpha subtype on human vascular smooth muscle cell proliferation, migration and fibronectin production

BACKGROUND

Vascular smooth muscle cell (SMC) migration, proliferation and extracellular matrix protein production are key steps in the formation of intimal hyperplasia, a process that leads to failure of vascular reconstructions. Protein kinase C (PKC) may be involved in all 3 cellular events. PKC consists of a family of 11 isotypes, 8 of which we have identified in human vascular SMCs. In this study we evaluate the role of PKCalpha as a second messenger for proliferation, migration and fibronectin production induced by human saphenous vein SMCs.

METHODS

DNA synthesis was evaluated by using (3)H-thymidine incorporation. Mitogen-activated protein kinase (MAP-K) activation was quantified by Western blotting with an antibody to its phosphorylated substrate, Elk-1. Chemotaxis was evaluated by using a microchemotaxis chamber. SMC fibronectin was measured by Western blotting. For all experiments, PKCalpha was blocked with a selective inhibitor, Gö6976.

RESULTS

Gö6976, at concentrations that allow selective inhibition of PKCalpha, inhibited platelet-derived growth factor-stimulated SMC proliferation and MAP-K activation by 30% to 40% and 30% to 60%, respectively. SMC chemotaxis was stimulated approximately 2-fold by the PKCalpha inhibitor. Neither basal nor transforming growth factor-betaI induced fibronectin production was affected by Gö6976.

CONCLUSIONS

Our data suggest that PKCalpha is a positive mediator of SMC proliferation and MAP-K activity, a negative regulator of migration and has no effect on SMC fibronectin production. These data suggest that modulating activities of specific PKC isotypes might be useful in both the study and control of intimal hyperplasia.

Usefulness of continuous oxygen insufflation into trachea for management of upper airway obstruction during anesthesia

BACKGROUND

Severe complications associated with upper airway obstruction often occur during the perioperative period. Development of a simple and reliable technique for reversing the impaired airway patency may improve airway management. The purpose of the current study is to evaluate the usefulness of transtracheal oxygen insufflation (TTI) for management of upper airway obstruction during anesthesia and to explore the mechanisms of TTI in detail.

METHODS

During propofol anesthesia in eight spontaneously breathing patients, the upper airway cross-sectional area and pressure-flow measurements during neck flexion with TTI were compared with those during triple airway maneuvers (TAM) without TTI. Blood gas analyses assessed efficacy of CO2 elimination during TTI in an additional nine patients.

RESULTS

TTI achieved adequate PaCO2 and PaO2 levels equivalent to those during TAM. In addition to a significantly smaller cross-sectional area during TTI, the location and slope of the pressure-flow relation during TTI completely differed from those during TAM, indicating that upper airway resistance was much higher during TTI. Notably, minute ventilation during TTI was significantly smaller than that during TAM, suggesting reduced dead space or other mechanisms for CO2 elimination.

CONCLUSIONS

TTI is capable of maintaining adequate blood gases through mechanisms different from those of conventional airway support in anesthetized subjects with upper airway obstruction.

Value of the profundapopliteal collateral index for selecting between an in-flow and sequential arterial reconstruction in patients with multisegment arterial occlusive disease

BACKGROUND

It remains difficult for surgeons to choose between an in-flow and sequential arterial reconstruction in patients with multisegment arterial occlusive disease. In addition, the exact criterion for the proper revascularization procedures of these patients also remains obscure.

METHODS

The profundapopliteal collateral index (PPCI) was determined in all patients with occlusions of both the aortoiliac and superficial femoral arteries prior to undergoing an arterial bypass. The PPCI in the inflow bypass (IB) was also compared with the sequential bypass (SB).

RESULTS

The symptoms of all patients undergoing either IB or SB improved. Preoperatively, the average PPCI in IB patients was significantly lower than that in SB patients. In addition, no significant difference was observed in the increased average rate of the ankle brachial index (ABI) between IB and SB.

CONCLUSIONS

The PPCI is an accurate predictor of the hemodynamic potential of the geniculate collaterals. In cases with a low PPCI, especially in patients with multisegment arterial occlusive disease, in-flow procedures alone may often be sufficient for the successful treatment of such patients. The PPCI is thus considered to be useful for selecting the optimal revascularization procedures.

Adsorption of glycosaminoglycans onto hydroxyapatite using chromatography

Proteoglycans are known to play an important role in the mineralization process, acting either as promoters or inhibitors. In this study the binding affinity of a variety of constituent glycosaminoglycan to hydroxyapatite was studied. Glycosaminoglycans (10-1000 microg ml(-1) in 0.02 M sodium acetate (pH 6.8) were constantly circulated through a hydroxyapatite column for 1 h. The total amount of glycosaminoglycan bound was determined by dimethylmethylene blue assay. The relative affinities of the different glycosaminoglycans remaining bound to hydroxyapatite was investigated by examining their release in a 0-1 M sodium phosphate gradient. Differences were noted between the desorption profiles of dermatan sulfate with two elution peaks and chondroitin 4-sulfate and chondroitin 6-sulfate each with a single peak. Dermatan sulfate and chondroitin 6-sulfate had a higher affinity for hydroxyapatite than chondroitin 4-sulfate possibly due to the presence of differing di-sulfated disaccharide ratios in the glycosaminoglycan chains. These findings suggest the presence of a variety of binding forms of each glycosaminoglycan or the differing orientation of these forms to yield different complexes with hydroxyapatite. The Ca2+ co-ordinates of the glycosaminoglycans are known to vary and may in part explain these findings.

Penetration of cisplatin into mouse brain by lipopolysaccharide

We investigated the penetration of cisplatin into the mouse cerebral cortex-rich region (CCR) induced by lipopolysaccharide (LPS). With the injection of cisplatin into mice 3 h after the LPS treatment, platinum was detected in the CCR during the 7 days after the injection, while platinum was not detected in the CCR of cisplatin-injected mice without LPS pretreatment and of mice simultaneous treated with cisplatin and LPS. The N(G)-nitro-L-arginine methyl ester dose-dependently lowered the platinum level. A dose of 5 mg/kg of aminoguanidine reduced the increase in the platinum level of the LPS-treated mouse, and platinum was no longer detected at doses of 20 mg/kg in the aminoguanidine-injected group. At doses of 500 mg/kg aminoguanidine, however, no effect was seen on the platinum level of the CCR induced by LPS. Regarding indomethacin, the injection of 5 mg/kg resulted in a decrease in the platinum content of the CCR, but not undetectable level. These results suggest that LPS increases the penetration of cisplatin into the mouse brain, and platinum may be accumulated in the CCR. Nitric oxide and prostaglandins contribute to the penetration of platinum into the cerebral cortex.

Analysis of hyaluronic acid in human gingival crevicular fluid using high-performance liquid chromatography

We determined the hyaluronic acid disaccharides, delta Di-HA, in the gingival crevicular fluid (GCF) and whole saliva of patients with periodontal disease, and in the peri-implant sulcus fluid (PISF) from sites around titanium osseointegrated implants, and compared these values with those in the GCF and whole saliva of controls. We also determined values for chondroitin sulfate disaccharide isomers at the same time. Glycosaminoglycans were extracted by digestion with Pronase E, followed by digestion of GAGs with hyaluronidase SD and chondroitinase ACII. Unsaturated disaccharide isomers produced from hyaluronic acid and chondroitin sulfate were analyzed by high-performance liquid chromatography (HPLC). The hyaluronic acid disaccharide delta Di-HA was found in all samples of GCF, PISF and whole saliva. The concentration of delta Di-HA in both GCF and whole saliva of the periodontitis group was greater than that in the controls. There was no difference in the concentration of delta Di-HA between the PISF and GCF of the controls. The ratios of hyaluronic acid to chondroitin sulfate in the GCF and in the whole saliva of the periodontitis group were significantly lower than that of the controls. There was no difference between the ratios in PISF and those in GCF of the controls. These results indicate that checking hyaluronic acid in GCF and whole saliva using HPLC is a useful means of assessing the condition of periodontal tissues, and that assaying hyaluronic acid in PISF may also be effective for monitoring the condition of tissues around dental implants.

Roles of nitric oxide and prostaglandins in the increased permeability of the blood-brain barrier caused by lipopolysaccharide

We investigated the involvement of nitric oxide (NO) and prostaglandins (PGs) in the damage to the blood-brain barrier (BBB) induced by lipopolysaccharide (LPS), using fluorescein as a tracer in mice. Aminoguanidine, a competitive inhibitor of inducible NO synthase (iNOS), when administered s.c. at 5 mg/kg, but not 500 mg/kg, reduced significantly the increase in brain fluorescein level after its i.v. injection in LPS-treated mice. When 1000 mg/kg of l-arginine, a substrate of NOS, were co-administered with 5 mg/kg of aminoguanidine to LPS-treated mice, the inhibitory effect of aminoguanidine on the increased fluorescein level disappeared. N(G)-Nitro-l-arginine methyl ester (l-NAME), a non-isoenzyme-selective NOS inhibitor, when administered s.c. at 5 mg/kg, only slightly reduced the LPS-induced increase in the brain fluorescein level. A pretreatment with dexamethasone, which suppressed the induction of both iNOS and cyclooxygenase 2 (COX-2), tended to decrease the brain fluorescein level in LPS-treated mice. Indomethacin, a COX inhibitor, at 5 mg/kg, but not 10 mg/kg, suppressed significantly the LPS-induced increase in the brain fluorescein level. These results involve that both the NO produced by iNOS and the PGs produced by COX contribute to enhance BBB permeability in LPS-administered mice.

L-arginine inhibits smooth muscle cell proliferation of vein graft intimal thickness in hypercholesterolemic rabbits

OBJECTIVE

The effect of the chronic administration of L-arginine on intimal thickness and the kinetics of smooth muscle cell proliferation in autovein grafts in hypercholesterolemic rabbits were examined.

METHODS

Male rabbits were fed a 1% cholesterol diet (control group) and a 1% cholesterol diet supplemented by 2.25% L-arginine HCl in drinking water (arginine group). Each group underwent reversed autologous vein bypass grafting of the left common carotid artery using the left external jugular vein. At 2 or 4 weeks after operation, intimal cell proliferation was determined by 5-bromo-2'-deoxyuridine (BrdU) incorporation and intimal thickness of the graft was measured with an ocular cytometer. At 4 weeks after operation, endothelium-dependent responses were examined by isometric tension recording.

RESULTS

At 4 weeks after operation, the level of plasma arginine and citrulline are significantly higher in the arginine group (n = 7), compared with the control (n = 7). Intimal thickness in the arginine group (n = 7) was significantly reduced, compared with that of the control (n = 7). At 2 weeks after operation, the BrdU labeling index of the control (n = 5) was significantly higher than that of the arginine group (n = 5). At 4 weeks after operation, ACh caused endothelium-dependent relaxation in the arginine group (n = 4), while in the control (n = 4), ACh did not relax.

CONCLUSIONS

These results suggest that smooth muscle cell proliferation of the rabbit jugular vein grafts during hypercholesterolemia occurs at an early stage after graft implantation, prior to the development of intimal thickness. Intimal thickness of vein graft during hypercholesterolemia was reduced by chronic administration of dietary L-arginine, by inhibiting smooth muscle cell proliferation. The enhancement of NO production in the blood vessel wall may therefore be useful for preventing late graft failure.

The effect of probucol on intimal thickening of autologous vein grafts in hyperlipidemic rabbit

Probucol is used to treat hypercholesterolemia and also has an anti-atherogenic effect. The effects of probucol on intimal thickening of autologous vein graft in hyperlipidemic rabbits with poor distal run-off were investigated. A poor distal run-off model was prepared in the right hindlimb of 18 rabbits allocated to four groups depending on diet: normolipidemic commercial diet, (NL group, n = 5); hyperlipidemic diet (HL group, n = 5); commercial diet with 1% probucol (NP group, n = 4); and hyperlipidemic diet with 1% probucol (HP group, n = 4). After 4 weeks the femoral vein grafts were implanted into normal (n = 18) or poor (n = 18) runoff limbs. Vein grafts were harvested 4 weeks after implantation. Intimal thickening of the graft was measured and macrophages therein examined immunohistochemically. The serum cholesterol level was not reduced by probucol treatment. The mean flow rate of the graft was significantly reduced in the poor run-off limb. On histological examination intimal thickening in the poor run-off limb was significantly greater than that of controls, while intimal thickening in the HL and HP groups was enhanced compared with that in the NL and NP groups, respectively. Mean intimal thickening in each limb in HP group rabbits was significantly lower than that in HL rabbits (microm): control (HL/HP): 99.4(7.4)/58.8(0.7) (P < 0.05); poor run-off (HL/HP): 155.3(9.6)/130.3(7.3) (P < 0.O5). There was no difference between NL and NP (microm): control (NL/NP): 44.6(24.7)/31.5(12.8); poor run-off (HL/HP): 115.3(13.8)/97.5(34.0). In addition, enhanced intimal thickening due to poor distal run-off was not suppressed. Immunohistochemical staining showed intimal macrophage infiltration in the HL and HP groups; however, macrophage infiltration in grafts in the HP group was less than in the HL group. In conclusion, under hyperlipidemic conditions, probucol decreased intimal thickening enhancement of the vein graft, and suppressed intimal macrophage infiltration. These findings were similar to the anti-atherogenic effect of probucol in the native artery. Hence, probucol administration after vascular reconstruction with vein grafts in patients with hyperlipidemia may be beneficial.

Chondroitin sulfate isomers in synovial fluid of healthy and diseased human temporomandibular joints

Synovial fluid was collected from the superior articular cavity of the temporomandibular joint in patients with unilateral internal derangement and joint pain whose contralateral joint was healthy. Glycosaminoglycans were liberated by digestion with pronase E, and precipitated with cetylpyridinium chloride and ethanol. Unsaturated disaccharide isomers of chondroitin sulfate, obtained following chondroitinase ACII digestion, were analyzed by high-performance liquid chromatography. Analytic data indicated that deltaDi-0S and deltaDi-6S were often found in chondroitin sulfate from the fluid of the diseased joints. The amounts of deltaDi-0S and deltaDi-6S differed significantly between synovial fluid samples from the diseased and healthy joints. Comparison of the relative proportions of the unsaturated disaccharides in the synovial fluid with previously reported values for several tissues, indicated that the chondroitin sulfate originated from articular cartilage, with possibly some contributions from soft connective tissues and serum present in the synovial fluid. These results suggest that chondroitin sulfate in the synovial fluid provides a useful indicator of the degree of internal derangement of the temporomandibular joint.

The inhibition of canine vein graft intimal thickening using a newly developed antiplatelet agent

OBJECTIVE

The purpose of this study was to evaluate the efficacy of a newly developed antiplatelet agent, 4-cyano-5, 5-bis[methoxyphenyl]-4-pentenoic acid (E5510) on intimal hyperplasia of experimental autologous vein grafts in a distal poor runoff canine model.

METHOD

The femoral vein was implanted into the femoral artery preparing a distal poor runoff model. These animals were divided into three groups consisting of the E5510 group, the Aspirin group, and the Control group. The vein grafts were harvested at either 1 or 4 weeks after implantation.

RESULTS

At 4 weeks, the degree of intimal hyperplasia of the graft of E5510 group was significantly less than that of the Aspirin group and the Control group (p < 0.05). No significant difference was observed between the Aspirin group and the Control group. At 1 week, the degree of intimal cell proliferation was determined by bromodeoxyuridine (BrdU) incorporation and was expressed as the BrdU labeling index. The BrdU labeling index of the E5510 group was also significantly lower than that of the Control group (p < 0.05).

CONCLUSIONS

These data demonstrate the efficacy of E5510 in reducing intimal hyperplasia of vein grafts under distal poor runoff conditions by reducing the degree of smooth muscle cell proliferation.

Surgical strategy of abdominal aortic aneurysm with preoperative renal failure

OBJECTIVES

To determine the effect of preoperative renal failure on the outcome of patients suffering from infrarenal abdominal aortic aneurysm (AAA).

METHOD

During the period from January 1979 to August 1995, 364 patients with AAA were admitted to our hospital and 323 underwent elective repair. The patients were retrospectively analysed in three groups. Group I was composed of 273 patients with a normal renal function who underwent an aneurysm repair. Group II was composed of 50 patients who demonstrated a preoperative renal dysfunction (creatinine above 2.0 mg/dl or creatinine clearance below 40 ml/min) and underwent an operation, including three patients maintained on chronic haemodialysis. Group III was composed of 18 patients with a renal dysfunction who did not undergo repair, including one patients maintained on chronic haemodialysis.

RESULTS

The operative mortality rate of groups I and II were 0.4% and 2.0%, respectively, although no significant difference was observed. The incidence of postoperative cardiac and pulmonary complications were also comparable in two groups. No patients required acute haemodialysis. The 5-year survival rate of group II (44%) was significantly higher than that of group III (20%), and seven of the 18 patients (39%) in group III ultimately died of a rupture of the AAA.

CONCLUSIONS

Patients with chronic renal failure can undergo an abdominal aortic aneurysm repair based on the same indications as those without renal failure.

Lipopolysaccharide-induced platinum accumulation in the cerebral cortex after cisplatin administration in mice: Involvement of free radicals

The relationship between the accumulation of platinum in the cerebral cortex following cisplatin administration and injury to the blood-brain barrier after lipopolysaccharide (LPS) treatment was investigated. The appearance of intravenously injected fluorescein in the brain was significantly increased 10-24 h after LPS treatment, the effect being dose-dependent. Platinum was detectable in the cerebral cortex of cisplatin-treated mice 24 h after LPS treatment, but not without LPS treatment. In mice pretreated with α-tocopherol, LPS administration did not significantly augment fluorescein penetration into the brain, whereas pretreatment with either allopurinol or ascorbic acid did not modify the LPS-induced increase in fluorescein penetration. In contrast, platinum in the cerebral cortex after cisplatin administration was still detectable in the allopurinol-, ascorbic acid-, and α-tocopherol-pretreated groups, and the levels of platinum in these groups were not significantly different from those in the group treated with LPS only. Administration of superoxide dismutase (SOD), but not of catalase, tended to inhibit the penetration of fluorescein. Both SOD and catalase significantly lowered platinum content in the cerebral cortex following cisplatin administration in mice treated with LPS. Thus, free radicals may injure the blood-brain barrier in mice challenged with LPS, and allow cisplatin to penetrate into the cerebral cortex, resulting in platinum accumulation.

Free radical scavengers suppress the accumulation of platinum in the cerebral cortex

We investigated whether free radical scavengers and antioxidants inhibit the accumulation of platinum (Pt) in the cerebral cortex. Pt was detected in the cerebral cortex of mice after administration of cisplatin and exposure to short-term hypoxia. When mice were treated with either allopurinol (20 mg/kg) or catalase (100 mg/kg) before cisplatin administration and low oxygen exposure, Pt was not detected in the cerebral cortex. However, Pt was detected in the cerebral cortex of mice pretreated with either a low dosage of allopurinol or heat-denatured catalase. Furthermore, Pt was detected in the cerebral cortex of mice preadministered vitamin C, vitamin E, or deferoxamine. Lipid peroxide levels in the cerebral cortex increased 10 min after the treatment of hypoxia, and peaked 30 min after the treatment. These results suggested that short-term hypoxia produces free radicals, which allows Pt to pass through the blood-brain barrier and accumulate in the cerebral cortex, and that the production of free radicals is reduced by the administration of either allopurinol or catalase, which prevents Pt from passing through the barrier.

Characteristics and localization of rat submandibular gland proteoglycans

The submandibular gland proteoglycans were investigated biochemically and immunohistochemically in male Sprague-Dawley rats. Proteoglycans were extracted with 4 M guanidine-HCl, followed by ultracentrifugation in a CsCl density gradient, and fractionated by ion-exchange chromatography and gel filtration. The molecular weight of PGs was estimated by SDS-PAGE and immunoblot analysis with monoclonal antibodies (HepSS-1 or 6-B-6). The glycosaminoglycan side-chains in the proteoglycan fractions were identified by electrophoresis on cellulose acetate membrane. Three proteoglycan fractions were obtained. One was a heparan sulphate proteoglycan that migrated as a diffuse band of about 210 kDa. The other two fractions contained at least two dermatan sulphate proteoglycans of 70-85 kDa and 40-50 kDa. Digestion of these two proteoglycans with chondroitinase ABC, but not heparitinase, produced two bands of 50 and 21 kDa, which were core proteins. The smaller dermatan sulphate proteoglycan may be a portion of the other, as the core protein of both bound to 6-B-6 antibody, and sugar chains of both were the same (20-30 kDa). Heparan sulphates recognized by antibody HepSS-1 were observed widely in the basement membrane, fibrous connective tissue, and striated and excretory ductal cells, while dermatan sulphate proteoglycans recognized by antibody 6-B-6 were located in the connective tissue surrounding striated and excretory ducts.

High-performance liquid chromatography analysis of chondroitin sulphate isomers in human whole saliva in a variety of clinical conditions

OBJECTIVES

Tests have been carried out to assess the level of unsaturated disaccharide isomers obtained from chondroitin sulphate in whole saliva, which contains chondroitin sulphate derived from gingival crevicular fluid (GCF).

MATERIALS AND METHODS

Whole saliva was collected from periodontally diseased subjects (PDS), clinically healthy subjects (CHS) and edentulous subjects (ES). Glycosaminoglycans (GAG) were liberated by digestion with Pronase E, and precipitated with cetylpyridinium chloride and ethanol. The unsaturated disaccharides obtained by chondroitinase ACII digestion of the liberated GAG were analysed by high-performance liquid chromatography. The unsaturated disaccharides included delta Di-0S, delta Di-6S and delta Di-4S.

RESULTS AND CONCLUSIONS

Analysis of data indicated that delta Di-0S, delta Di-6S and delta Di-4S were found in all PDS samples. The amount (ng ml-1 collected whole saliva) of delta Di-0S, delta Di-6S and delta Di-4S (P < 0.01) indicated significant differences between CHS and PDS whole saliva samples. The quantities of delta Di-0S and delta Di-4S (P < 0.01) indicated significant differences between PDS and ES whole saliva. The amount of delta Di-0S (P < .05) and delta Di-6S (P < 0.01) also indicated significant differences between CHS and ES whole saliva. These results indicate that chondroitin sulphate in PDS and CHS whole saliva is representative of that previously reported in gingival crevicular fluid and so provides a useful and alternative means of assessing the role of GAG as indicators of periodontal disease.

Age changes in the rat temporomandibular joint articular disc: a biochemical study on glycosaminoglycan content

The temporomandibular joint (TMJ) articular discs were removed from female Sprague-Dawley rats 3, 5, 10, 32, 90 and 130 weeks of age. Glycosaminoglycans (GAGs) were extracted from the discs by heat treatment, alkali treatment and digestion with Pronase E, and purified by precipitation with cetylpyridinium chloride and ethanol. The concentration of total GAG was highest in the 3 week extracts and tended to decrease with age. Dermatan sulphate was the predominant GAG detected in all age groups along with chondroitin sulphate, hyaluronic acid and heparan sulphate. The disaccharides obtained from chondroitin sulphate were delta Di-4S, delta Di-6S and delta Di-0S, with delta Di-4S being the predominant isomer followed by delta Di-6S for all ages of all the GAG examined. The concentration of chondroitin sulphate showed a decrease with age. Quantitative changes of GAG with age may be related to functional changes in TMJ discs.

Disaccharide analysis of chondroitin sulfate in peri-implant sulcus fluid from dental implants

We collected peri-implant sulcus fluid by capillary tubes from sites around titanium osseointegrated implants and determined the chondroitin sulfate released into the peri-implant sulcus fluid by high-performance liquid chromatography. Chondroitin sulfate was found in all peri-implant sulcus fluid samples, and its content was similar to that in gingival crevicular fluid obtained around natural teeth. The predominant unsaturated disaccharide isomer was delta Di-0S, followed by delta Di-4S. Delta Di-6S was present in trace amounts. The amount of delta Di-0S was greater in peri-implant sulcus fluid than in gingival crevicular fluid. Assaying chondroitin sulfate disaccharides in peri-implant sulcus fluid may be an effective method of monitoring the peri-implant condition of dental implants.

Disaccharide analysis of chondroitin sulphate in human gingival crevicular fluid using high-performance liquid chromatography

Gingival crevicular fluid (GCF) was collected into capillary tubes from healthy gingiva and sites of advanced periodontitis. Following digestion with Pronase E, the glycosaminoglycans were isolated by successive precipitation into 5% cetylpyridinium chloride and 95% ethanol. Unsaturated disaccharide isomers of chondroitin sulphate, obtained following chondroitinase ACII digestion, were analysed by high-performance liquid chromatography. Chondroitin sulphate was found in all GCF samples, with greater amounts in patients with periodontal disease than at control sites with a relatively healthy periodontium. The predominant isomer in the periodontal diseased group was delta Di-4S, while that in the control group and serum samples was delta Di-0S. Comparison of the relative proportions of the unsaturated disaccharides in GCF with previously reported values for alveolar bone, cementum, gingiva and periodontal ligament, as well as for serum, indicates that the chondroitin sulphate present in GCF of patients with periodontal disease originated from the mineralized connective tissues of the periodontium, notably alveolar bone, possibly with some contributions from soft connective tissues of gingiva and periodontal ligament and from serum.

High-performance liquid chromatography analysis of chondroitin sulfate isomers in human periodontium

We investigated the chondroitin sulfate in human periodontal samples (gingiva, periodontal ligament, cementum and alveolar bone) collected for orthodontic reasons. Glycosaminoglycans (GAGs) were extracted from the periodontium by enzyme digestion, and unsaturated disaccharide isomers of chondroitin sulfate were obtained by chondroitinase ACII and hyaluronidase digestion. The isomers were analyzed by high-performance liquid chromatography. Chondroitin sulfate was found in all four types of periodontal tissue; its unsaturated disaccharide isomers consisted in delta Di-0S, delta Di-6S, delta Di-4S, delta Di-diSE and delta Di-triS. These four types of periodontal tissue showed different molar ratios of the unsaturated disaccharides. The ratio of delta Di-4S to delta Di-6S was greater in the calcified than in the uncalcified tissue.

Changes in synovial fluid N-acetyl-beta-glucosaminidase activity in the human temporomandibular joint with dysfunction

beta-Glycosidases (N-acetyl-beta-glucosaminidase, N-acetyl-beta-galactosaminidase, beta-glucuronidase) were assayed in temporomandibular joint (TMJ) synovial fluid obtained from 23 patients with closed lock TMJ internal derangement (ID), four with closed-lock TMJ osteoarthritis (OA), and 13 with normal controls (N). Synovial fluid was collected from the upper joint space after injecting 1.5 ml of 1% lidocaine three times. The specific activity of N-acetyl-beta-glucosaminidase increased significantly both with ID (p < 0.01) and with OA (p < 0.001), along with increases in the activity of N-acetyl-beta-galactosaminidase (p < 0.05 with ID and p < 0.01 with OA) and in beta-glucuronidase (p < 0.05 both with ID and OA). The N-acetyl-beta-glucosaminidase activity with OA was also significantly higher (p < 0.001) than with ID. These findings suggest that N-acetyl-beta-glucosaminidase activity in the TMJ synovial fluid reflects the degree of TMJ dysfunction.

Glycosaminoglycans in the lamina propria and submucosal layer of the monkey palatal mucosa

Glycosaminoglycans (GAGs) in monkey palatal lamina propria plus both fatty and glandular zones of palatal submucosa were compared. Chemical analysis revealed that GAG contents of the lamina propria and glandular zone were higher than that of the fatty zone. The four GAGs identified by electrophoretic analysis were hyaluronic acid, dermatan sulfate, chondroitin sulfate and heparan sulfate. Each mucosal layer contained all four GAG components. The predominant GAG in both the lamina propria and glandular zone was dermatan sulfate followed by hyaluronic acid. The reverse situation (predominant hyaluronic acid, less prominent dermatan sulfate) was noted in the fatty zone of the submucosa. The three tissue regions showed different molar ratios of unsaturated chondroitin sulfate disaccharides. The ratio of delta Di-4S to delta Di-6S was lower in the lamina propria than in either the fatty or glandular submucosal zones.

Analysis of chondroitin sulfate isomers in the periodontium of the monkey using high-performance liquid chromatography

Glycosaminoglycan (GAG) was extracted from monkey periodontium, consisting of gingiva, periodontal ligament, alveolar bone and cementum, and from dental pulp and dentin by digestion with Pronase E. Unsaturated disaccharide isomers formed by chondroitinase AC digestion from chondroitin sulfate were labeled with dansylhydrazine and analyzed by high-performance liquid chromatography. These tissues showed different molar ratios of the unsaturated chondroitin sulfate disaccharides. The ratio of delta Di-4S to delta Di-6S was lowest in the dental pulp, followed by the gingiva, periodontal ligament, dentin, alveolar bone, and cementum, in that order. It was greater in the calcified than in the uncalcified tissues.

A biochemical study of glycosaminoglycans in the palatal rugae of the monkey (Macaca fascicularis)

Glycosaminoglycans (GAG) were extracted from the connective tissue of the palatal rugae, separated by electrophoresis and compared with the results obtained for the remaining palatal mucosal and gingival connective tissues. The GAG content of the rugae (3.01 mg/g defatted dry weight) was higher than in the remaining palatal mucosa (2.33 mg/g defatted dry weight) or gingiva (1.68 mg/g defatted dry weight). Dermatan sulphate was the predominant GAG in both the palatal rugae (48% of total GAG) and the remaining palatal mucosa (50%) followed by hyaluronic acid (33 and 31% respectively). The results do not support previous histochemical observations in which the rugae appeared to be rich in hyaluronic acid.