Randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part III: comparisons of patient satisfaction

STATEMENT OF PROBLEM

There is insufficient evidence to indicate the functional superiority of mandibular implant-supported overdentures to justify their use in edentulous patients.

PURPOSE

This study compared the benefits perceived by patients who received a new maxillary denture and a mandibular conventional denture (CD) and an implant-supported overdenture (IOD).

METHOD

New maxillary and mandibular dentures were delivered to 89 diabetic denture wearers with clinically acceptable metabolic control who treated their diabetes either with insulin (IT) or without insulin (NIT). Of the 89 patients, 37 received maxillary and mandibular CDs and 52 received a maxillary CD and an IOD. Two questionnaires with categorical responses were used; the first contained 13 questions to ascertain a patient's absolute assessments of original dentures at entry and study dentures at 6- and 24-months after treatment completion; the second questionnaire had 11 questions that assessed the relative change perceived by patients with study dentures. Of the 78 patients who completed the posttreatment (PT) assessments at 6 months, 68 patients provided longitudinal data for questionnaire I and cross-sectional data for questionnaire II. In addition, 46 patients (18 CD and 28 IOD) also provided PT assessments at 24 months.

RESULTS

Both mean scores and percentage distributions of longitudinal data for questionnaire I showed perceptual improvements with both types of study dentures. Improvements were higher in the IOD than in the CD group. Mean scores failed to show any significant differences between the 2 treatment groups. The only significant difference was found in the change in percentage distributions for perceptual chewing ability in favor of the IOD group. Even this advantage was lost at 24 months. With the comparative questionnaire, a higher percentage of patients in the IOD group than in the CD group perceived improvements with study dentures from their original dentures in chewing ability, chewing comfort, and denture security. However, mean differences were statistically significant in favor of the IOD group only for chewing ability and less difficulty to chew hard foods.

CONCLUSION

The mandibular implant-supported overdenture offers same advantage in terms of perceived chewing function over the conventional denture.

Support for the availability of prenatal testing for neurological and psychiatric conditions in the psychiatric community

Faculty and residents of the University of Michigan Department of Psychiatry, members of the Alliance for the Mentally Ill (AMI), and university students were surveyed to elicit attitudes toward the availability of prenatal testing and genetic therapy or enhancement for early- and late-onset psychiatric diseases compared to neurological disorders and human traits. They were asked to complete a written questionnaire designed to assess their opinions as to whether prenatal testing and genetic therapy or enhancement should be applied to 16 selected "disease" phenotypes or human traits: eight early- and late-onset psychiatric conditions, four neurological disorders, and four human traits. Twenty-two percent returned the written survey. The majority of all respondents supported the availability of prenatal testing for well-defined, serious psychiatric or neurological phenotypes and found testing for human traits less desirable. The percentages of respondents supporting availability of testing increased if in utero curative gene therapy was available. Response to the survey differed on the basis of gender and age, as well as personal versus professional familiarity with the condition. The results of this pilot study suggest that a majority of the population, including psychiatrists, will support the public availability of prenatal diagnosis for serious psychiatric or neurological phenotypes, even if no in utero curative therapy is available. Support for testing for human traits was not strongly endorsed.

Collateral resistance of a dideoxycytidine-resistant cell line to 5-fluoro-2'-deoxyuridine

Exposure of a human lymphocytic cell line, H9 cells, to 0.5 microM and 5.0 microM dideoxycytidine (ddC) resulted in isolation of ddC-resistant H9-ddC0.5w and H9-ddC5.0w cell lines. In addition, these cell lines were also resistant to azidothymidine and had reduced deoxycytidine kinase and thymidine kinase activities. We now show that these cell lines are 4-fold and 2000-fold collaterally resistant to 5-fluoro-2'-deoxyuridine (FdUR), respectively, but not to 5-fluorouracil (FU). Biochemical evaluations show that, compared to the parental cells, the FdUR phosphorylation was reduced to 36.3% and 9.2% and the FdUMP levels were decreased to 48.1% and 1.2% in these cell lines. Taken together, the data suggest that ddC, an antiviral agent, is capable of inducing resistance to FdUR-a drug that is not its analog and which has a different metabolism, target site, and mechanism of action.

[Association of polymorphisms of apolipoprotein B gene with cholesterol gallstone disease]

OBJECTIVE

To investigate the association between the apolipoprotein B (apoB) gene polymorphic sites Ins/Del and Xbal, and cholesterol gallstone disease.

METHODS

The two polymorphic sites of apoB gene were examed in 101 cholesterol gallstone patients and 50 controls by polymerase chain reaction and restriction fragment length polymorphism methods.

RESULTS

For Xbal polymorphic site, the frequency of the rare allele X+ and the distribution of X+X- genotype were significantly higher in the patient group than in the control group (P < 0.05). For Ins/Del polymorphic site, no significant difference was found in allele frequency and genotype distribution between the patient group and the control group.

CONCLUSIONS

Xba1 polymorphism of apoB gene may be associated with cholesterol gallstone disease. The association, however, is not present for Ins/De1 polymorphism of apoB gene with cholesterol gallstone disease.

[Correlation between gene expression of CCK-A receptor and gallbladder emptying in gallstone patients]

OBJECTIVE

To investigate the expression of CCK-A receptor and its relation with gallbladder hypomotility in patients with gallstone.

METHODS

20 patients with gallstone and 10 normal subjects were studied and gallbladder emptying function was measured by B ultrasonography. The other 8 patients without gallstone who died of accident were selected as controls for measuring mRNA expression of CCK-A receptor of gallbladder; RT-PCR was used to explore gene expression of CCK-A receptor of gallbladder.

RESULTS

The gallbladder motility was significantly impaired in gallstone patients. The patients had lower mRNA expression of CCK-A receptor than control subjects (0.633 +/- 0.167 vs. 0.944 +/- 0.230, P < 0.01), and so did patients with impaired gallbladder motility then those with normal motility (0.544 +/- 0.124 vs. 0.768 +/- 0.131, P < 0.05). Furthermore, the change of expression of CCK-A receptors was markedly correlated with gallbladder emptying (r = 0.925, P < 0.01).

CONCLUSIONS

mRNA expression of CCK-A receptor in gallstone patients decreases, which was related to gallbladder hypomotility. The down-regulation of gene expression of CCK-A receptor plays an important role in gallbladder hypomotility in patients with gallstone.

[Effects of short veno-venous hemofiltration on severe acute pancreatitis]

OBJECTIVE

To estimate the effects of therapy of short veno-venous hemofiltration (SVVH, 4hr) on severe acute pancreatitis (SAP).

METHODS

Twenty patients were divided randomly into hemofiltration group (HF, 10 pts) and non-hemofiltration group (NHF, 10 pts). The local, systemic manifestations were compared between two groups; and the concentration of serum pro-inflammatory cytokines (TNFalpha, IL-1beta, IL-6, IL-8, sIL-2R) and anti-inflammatory cytokines (IL-2, IL-10) were determined at different observation points.

RESULTS

In the HF and NHF group, the duration for disappearance of abdominal pain and tenderness, and amelioration for abdominal distension was (8.5 +/- 6.3) d vs. (90.0 +/- 49.0) d and (16.9 +/- 5.2) d vs. (63.4 +/- 36.0) d. CT scores at the 14th day and APACHE II scores at the 10th day was (5.6 +/- 1.3) vs. (7.7 +/- 0.8) and (4.5 +/- 1.5) vs. (7.4 +/- 2.1). The average hospital stay and cost of therapy were (33.0 +/- 20.7) d vs. (56.4 +/- 16.0) d and (53,200 +/- 16,000) vs. (89,100 +/- 25,000) RMB (P < 0.05). The concentration of 5 serum pro-inflammatory cytokines at each observation points after hemofiltration was decreased significantly (P < 0.05) in the HF group. But the concentration of the two serum anti-inflammatory cytokines was increased significantly (P < 0.05) as compared with that of the NHF group.

CONCLUSIONS

Through SVVH, the imbalance of pro-inflammatory and anti-inflammatory cytokines has been corrected at early stage; thus, the severity of the disease is ameliorated significantly and the efficacy of therapy is increased.

A randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part II. Comparisons of masticatory performance

STATEMENT OF PROBLEM

Convincing evidence is lacking to demonstrate the functional superiority of mandibular implant-supported overdentures over conventional dentures.

PURPOSE

This randomized clinical trial was conducted to compare masticatory functional effectiveness of mandibular implant-supported overdentures and conventional dentures in diabetic denture wearers with clinically acceptable metabolic control.

METHODS

A total of 102 edentulous diabetic patients, treated with or without insulin, were randomized to receive a new maxillary and either a mandibular conventional denture or an implant-supported overdenture. Treatment was completed in 89 patients, 37 with conventional dentures and 52 with Hader bar-clip attachment overdentures supported by two IMZ implants. Besides data from medical and dental histories, oromaxillofacial examinations, and questionnaires, masticatory tests were performed by patients before and at 6 and 24 months after treatment completion. Although 78 patients (28 in the conventional, 50 in the overdenture group) performed tests at 6 months after treatment, 68 (25 in the conventional, 43 in the overdenture) had performance data for both entry and 6-month posttreatment intervals.

RESULTS

The two treatment groups were highly comparable in terms of general characteristics, quality of original dentures, tissue support, and past denture experience. No significant differences were found between patients treated for diabetes with or without insulin. All four masticatory performance scores with original dentures were higher in the conventional denture group than the overdenture group. The posttreatment performance scores for the two treatment groups became similar because of the higher gains in the overdenture group. Patients with low initial performance scores showed greater posttreatment gains with both conventional dentures and overdentures.

CONCLUSIONS

The implant-supported overdenture showed no significant advantage over the conventional denture for improving the ability to comminute food in this group of diabetic patients with higher than average initial functional levels observed for other groups of denture wearers in previous studies.

A randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part I: Methodology and clinical outcomes

STATEMENT OF PROBLEM

Scientific evidence is lacking to support the general application of implant-supported mandibular overdentures.

PURPOSE

This randomized clinical trial was undertaken to compare the efficacy of conventional mandibular and implant-supported overdentures in diabetic edentulous patients with clinically acceptable metabolic control.

METHOD

A total of 102 diabetic patients, treated with or without insulin, were randomized to receive a new maxillary denture and either a conventional or an implant-supported removable mandibular overdenture. Treatment was completed for 89 patients, 37 with the conventional and 52 with implant-supported dentures. Detailed examinations, tests, and questionnaires were given before and at 6- and 24-months after treatment completion. Comparisons between the two treatment groups were made for treatment failures based on prespecifed criteria and the type and amount of maintenance care provided.

RESULTS

The insulin and noninsulin treated groups were collapsed because of the lack of significant differences at entry. The conventional denture and implant-supported overdenture groups were similar in terms of general demographics, medical status, quality of their original dentures and denture support, several functional measures, and patient satisfaction. Treatment was judged to be successful in 56.9% of patients with conventional dentures and 72.1% with overdentures. This difference in success rate was not statistically significant (p > 0.05). Patients with treatment failures in both groups required excessive maintenance care. Those with conventional dentures needed frequent denture base adjustments and relines, whereas those with overdentures required frequent clip replacements and repairs. Although significant improvements were seen with both treatment modalities, a higher percentage of patients with implant-supported overdentures than those with conventional dentures reported improvements in chewing comfort and moderate-to-complete overall satisfaction.

[Polymorphism at the LDL receptor gene locus in patients with cholesterol gallstone disease]

OBJECTIVE

To investigate the association between the dinucleotide repeat polymorphism at the 3' end of the LDL receptor gene and cholesterol gallstone disease.

METHODS

Polymorphism of the (dTA)n was amplified by using polymerase chain reaction, and the alleles identification was performed with denaturing polyacrylamide gel electrophoresis and silver stain technique.

RESULTS

Analysis of allele frequencies in 131 unrelated Chinese gallstone patients and 79 controls indicated that the C allele was more frequent in the patients with cholesterol gallstones than that in the controls (0.40 vs 0.27, P < 0.01), and the frequency of the BB genotype of the LDL receptor gene was markedly lower (P < 0.005), while the CC and BC genotypes were significantly higher in the patients with cholesterol gallstones than in the controls respectively (P < 0.05, P < 0.05).

CONCLUSION

The present study suggests that the LDL receptor gene polymorphism may be associated with cholesterol gallstone disease.

A bone regenerative approach to alveolar ridge maintenance following tooth extraction. Report of 10 cases

TEN PATIENTS WHO REQUIRED two or more anterior teeth extractions were utilized in this study. Extraction procedures were carried out with a full thickness surgical flap approach. After flap reflection, teeth were removed with a minimum of trauma to the surrounding bone. Following extraction silicone-based impression techniques were used to produce a model of the alveolar process and small metal pins were placed in the alveolus to be used as fixed points to make measurements of ridge dimensions. One socket was covered with an expanded polytetrafluoroethylene (ePTFE) barrier membrane (experimental site); the other socket was a conventional control. The soft tissue flaps were then mobilized using periosteal releasing incision and the wound closed with ePTFE mattress sutures. Six months following extraction, patients were treated with flap surgery to expose both extractions sites to remove the ePTFE membranes and to measure ridge dimensions using the pins as fixed points. Clinical and model measurements have shown statistically significant better ridge dimensions at experimental sites than at control (P < or = 0.05). Three patients with exposed membranes had similar dimensional changes as controls. Results from this study suggested that this improved technique offers a predictable alveolar ridge maintenance enhancing the bone quality for dental implant procedures and esthetic restorative dentistry.

[Pancreatic ischemia: a continuous injury factor in acute necrotic pancreatitis]

ANP model in rats was used to determine the concentration of TXB2, PGF1 alpha in plasma and the ACE activity in serum in five groups. The concentration of TXB2, PGF1 alpha in all experimental groups was significantly different from that of control group (P < 0.05). The comparison of ACE activity was just the same as the above except that of 6 h. The factors leading to pancreatic ischemia functioned continously. We conclude that pancreatic ischemia is a continuous injury factor in ANP, and there is no reperfusion-injury in the course of the disease.

Fatty acid unsaturation increases expression and capping of murine lymphocyte CD44 and CD45

We studied the effect of incubating murine lymphocytes with cis-unsaturated fatty acids on expression and capping of CD44 and CD45. Lymphocytes were incubated with stearic (18:0) or oleic (18:1 omega-9) acid bound to bovine serum albumin (BSA). After incubation with rat anti-CD44 or anti-CD45 monoclonal antibodies and then with fluorescent-labeled anti-rat antibody, mean fluorescence intensity (FI) was measured by using flow cytometry. Capping was measured after warning and fixation in paraformaldehyde. Steady-state fluorescence anisotropy (rs) was measured after the cells had been incubated with trimethylammoniumdiphenylhexatriene. Incubation with oleic acid, but not stearic acid or BSA alone, was associated with an increase in FI of CD44. Expression of CD45, however, was increased by both stearic and oleic acids to the same degree over BSA controls. CD44 and CD45 capping were both increased by incubation with oleic acid. Rs was decreased in cells incubated with oleic acid, suggesting an increase in membrane fluidity. We conclude that incubation with oleic acid increases expression of CD44 and increases capping of both CD44 and CD45. These findings were confirmed in feeding experiments, in which rs was reduced and CD44 capping increased by polyunsaturated fatty acid diets.

Involvement of CD44 and the cytoskeletal linker protein ankyrin in human neutrophil bacterial phagocytosis

The leukocyte CD44 and CD45 cell surface receptors are associated via the linker proteins ankyrin and fodrin with the cytoskeleton, which itself is important in immune cell functions such as adherence, chemotaxis, and phagocytosis. The effects of rat antihuman CD44 and CD45 monoclonal antibodies on phagocytosis of fluoresceinated heat-killed Staphylococcus aureus 502A by normal human neutrophils (PMNs) during 2 hr incubation in RPMI-1640 was studied via flow cytometry and confocal microscopy. Flow cytometry was performed using an excitation wavelength of 488 nm, fluorescence being measured at 515-560 nm on 50,000 PMNs per sample. Confocal microscopy was performed on samples after further incubation with rhodamine-conjugated antiankyrin. Anti-CD44 resulted in an increase of 27-31% compared to control (P = 0.004) in the proportion of PMNs fluorescing, an increase of 17-24% (P = 0.001) in mean intracellular fluorescence per PMN, and an increase in total PMN fluorescence of 50-58% compared to control (P < 0.001). In contrast, anti-CD45 had little effect on phagocytosis. Colchicine (a microtubule-disrupting agent) enhanced, whereas cytochalasin-D (a microfilament inhibitor) inhibited bacterial phagocytosis; cytochalasin-D completely abrogated the effect of anti-CD44 on this PMN function. Hyaluronic acid augmented phagocytosis by an increment similar to that observed with anti-CD44. Two-color flow cytometry and confocal microscopy demonstrated that ankyrin always colocalized with ingested fluorescein isothiocyanate (FITC)-labeled bacteria. These data strongly suggest that CD44 is involved in bacterial phagocytosis, provide further evidence of CD44 receptor linkage to cytoskeletal elements in human leukocytes, and suggest that ankyrin has a significant role in the transport of phagosomes.

Supplemental L-arginine HCl augments bacterial phagocytosis in human polymorphonuclear leukocytes

That L-arginine (L-Arg) augments the host response to acute bacterial sepsis suggests that this amino acid intervenes early in the immune response, perhaps via the nitric oxide synthetase (NOS) pathway. The effect of L-Arg supplementation on in vitro phagocytosis of fluorescein-labeled, heat-killed Staphylococcus aureus by peripheral blood neutrophils (PMNs) from 12 normal human volunteers was studied. Separated PMNs were incubated for 2 h with labeled bacteria, with and without supplemental L-Arg, D-arginine, glycine, and/or the NOS inhibitors L-canavanine, aminoguanidine, or L-NG-nitroarginine methyl ester. PMNs were fixed and extracellular fluorescence quenched with crystal violet. By flow cytometry and confocal microscopy, L-Arg supplementation was shown to result in a highly significant increase in PMN bacterial phagocytosis, the maximal effect being seen with L-Arg 380 microM and falling off with higher concentrations. This augmentation was completely abrogated by NOS inhibitors in molar excess, but inhibitors alone did not suppress phagocytosis below that of unsupplemented controls. Neither D-arginine nor glycine affected phagocytosis; the L-Arg effect was stereospecific and not related to utilization of L-Arg as an energy source. L-Arg supplementation significantly enhances bacterial phagocytosis in human neutrophils, perhaps by effects on cytoskeletal phenomena, and this appears to be mediated through NOS activity. Phagocytosis by nonspecific immune cells which intervene early in the response to sepsis is critically important, and beneficial effects of L-Arg on the clinical course of sepsis may be due at least in part to augmentation of phagocyte function.

[Experimental studies on effects of zinc and germanium on immune function and anti-oxidation in mice]

Zinc and germanium concentrations in serum, liver and muscle of mice, T-lymphocyte subgroup proportion, serum superoxide dismutase (SOD) activity and malonodialdehyde (MDA) were determined to study whether there exist synergism or antagonism between zinc and germanium. Results showed there existed, to certain extent, competitive effects of serum zinc and germanium in mice. When concentration of serum zinc increased, that of germanium decreased, or vise versa. There existed certain relationship between zinc and germanium concentrations in serum and those in muscle and liver of mice, and between those and CD3 count and SOD activity. Immune function in mice was influenced and their T-lymphocyte subgroup proportion changed with changes in serum zinc and germanium concentrations. With increased germanium and decreased zinc serum concentrations, CD3 and CD1 counts decreased, CD8 count unchanged, and the ratio of CD1 to CD3 decreased, which showed certain antagonist effects of them as they operated together. But, no antagonism was observed in their anti-oxidant effects, SOD activity increased to varied extent, and the level of MDA decreased.

Diets high in polyunsaturated oils decrease lymphocyte membrane anisotropy and B-cell mitogenesis

Balb/c mice were fed semipurified diets containing 40% of total calories as lipids: olive, safflower, or fish oil. After 2 weeks of feeding, splenic mononuclear cells were isolated and assayed for steady-state fluorescence anisotropy by means of the probe diphenylhexatriene. Splenocytes were also incubated with the mitogens concanavalin A, phytohemagglutinin, or lipopolysaccharide; subsequent uptake of tritiated thymidine was measured as an index of proliferation. No differences were observed in the membrane anisotropy and mitogenesis of mice fed the olive oil diet (high in monounsaturated fatty acids) and the control group. However, membrane anisotropy was significantly lowered in mice fed the safflower or fish oil diets (high in polyunsaturated fatty acids), and the mitogenic response to lipopolysaccharide was suppressed. Mitogenic responses to concanavalin A and phytohemagglutinin were not significantly affected by the type of lipid in the diet.

[Free fatty acids in gallbladder bile]

Using gas chromatography and high performance liquid chromatography (HILC), we examined free fatty acid and lecithin molecular species in gallbladder biles from patients with cholesterol gallstones. Effect of free fatty acids on cholesterol nucleation in model bile was studied by a sensitive cholesterol crystal growth assay. Compared to bile of controls, biles from patients with gallstones had higher total free fatty acid level, more palmitic acid, more stearic acid, more linoleic acid and arachidonic acid. The lecithin pattern was similar in all. After free fatty acids were added to model bile, palmitic acid, oleic, acid, linoleic acid and arachidonic acid had significant effect of pro-nucleating, free fatty acids on non-protein pro-nucleating factor. These data suggest that variations in quantitation and composition of free fatty acids are importanct in the pathogenesis of cholesterol gallstone formation.