Association of plasma homocysteine and macular edema in type 2 diabetes mellitus.

PURPOSE: The aim of this study was to assess the association of macular edema (ME) with plasma homocysteine, vitamin B6, vitamin B12, and folic acid levels in patients with Type 2 diabetes. METHODS: Sixty-five diabetic subjects with no retinopathy and nonproliferative diabetic retinopathy (NPDR) (no DR, without ME, with ME: 16, 25, 24, respectively), 28 with proliferative diabetic retinopathy (PDR) (with and without ME: 14, 14, respectively), and 19 healthy subjects as control were recruited in this cross-sectional study. Plasma homocysteine, vitamin B12, vitamin B6, and folate levels were determined after 8-hour of fasting for all subjects. The levels of serum homocysteine and vitamin B6 were measured using high performance liquid chromatography (HPLC) with fluorescence detection, and the levels of serum vitamin B12 and folic acid were measured by electrochemiluminescence immunoassay. RESULTS: When diabetic groups with ME were compared with diabetic groups without ME for homocysteine, vitamin B12, vitamin B6, and folic acid, the only significant difference was detected in homocysteine levels (p=0.001). There was no significant difference between NPDR with ME group compared with NPDR without ME group and no DR group for plasma homocysteine, vitamin B12, vitamin B6, and folic acid (p=0.200, p=0.660; p=0.999, p=0.678; p=1.0, p=0.248; p=1.0, p=0.982, respectively). On the other hand, when PDR with ME group was compared with PDR without ME group, there was only significant difference in homocysteine levels (p=0.023). CONCLUSIONS: Mild to moderate elevation of homocysteine may explain the role of vascular dysregulation and endothelial dysfunction in patients with DR. The present study suggests hyperhomocysteinemia may be one of the crucial risk factors for development of ME.

Lipid peroxidation and antioxidant status in lichen planus.

BACKGROUND: Lichen planus (LP) is an inflammatory skin disease of unknown aetiology. Recently, increased oxidative stress has been implicated in the pathogenesis of various skin diseases such as atopic dermatitis, psoriasis vulgaris and vitiligo. AIM: To evaluate the status of the oxidative stress and antioxidant defence system in patients with LP. METHODS: In total, 40 patients with LP (23 men, 17 women; mean +/- SD age 43.27 +/- 1.96 years) and 40 control subjects, matched for age and gender, were enrolled in this prospective study. The exclusion criteria included medication with immunosuppressive agents, history of trauma and surgery, and history of alcohol ingestion for at least 1 month prior to the study. The serum nitric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD) levels and the erythrocyte catalase (CAT) levels were investigated in both groups. RESULTS: Mean +/- SD levels of serum NO (74.60 +/- 17.96 micromol/L) and MDA (18.24 +/- 5.21 micromol/L) in patients with LP were higher than those of the control group (P = 0.007 and P = 0.031, respectively). Serum SOD levels (18.19 +/- 3.71 U/mL) in patients with LP were also higher than in healthy controls (P = 0.002). In contrast, erythrocyte CAT levels (13 557.80 +/- 4134.42 U/kg haemoglobin) were significantly lower in the patient group than in the control group (P = 0.009). CONCLUSIONS: The findings of this study suggest that increased oxidative stress, increased lipid peroxidation and an imbalance in the antioxidant defence system may be involved in the pathogenesis of LP.

Levels of zinc, iron, and copper in patients with pseudoexfoliative cataract.

PURPOSE: To investigate the aqueous humor, lens, and serum concentrations of zinc, iron, and copper in patients with pseudoexfoliative cataract and compare with patients who have senile cataract without pseudoexfoliation. METHODS: Twenty-five patients with pseudoexfoliative cataract and 25 patients with senile cataract as control group were enrolled in the study. Samples from aqueous humor, serum, and lens materials during extracapsular cataract extraction (ECCE) were collected from all patients. The levels of selected trace elements in three samples in all groups were assayed with atomic absorption spectrometry (AAS) and statistical analyses were performed with t-test for independent samples except lens zinc and serum copper levels. The data weren't normally distributed, therefore Mann-Whitney U test applied for these parameters. RESULTS: The zinc and copper levels in aqueous humor of PEX group were significantly higher than those of control group (p<0.001). The iron levels in aqueous humor were not significantly different in PEX group and control group (p=0.252). The copper content of lenses was significantly increased in PEX group compared to control group (p=0.029). The iron and zinc content of lenses had no significant differences between the two groups (p=0.248, p=0.719, respectively). The levels of iron and copper in serum were significantly increased in PEX group compared to control group (p<0.001 and p<0.002, respectively). The zinc level in serum had no significant differences between the two groups (p=0.823, p=0.472, respectively). CONCLUSIONS: Zinc, iron, and especially copper may play a role in PEX syndrome.

The value of routine antibiotic prophylaxis in mandibular third molar surgery: acute-phase protein levels as indicators of infection.

Postoperative infections in the oral region are usually caused by anaerobic bacteria. While some authors claim that routine antibiotic prophylaxis is necessary after third molar surgery, others do not recommend this practice. The major subject of controversy is what constitutes postoperative infection. Previous studies that have examined the benefit of routine antibiotic prophylaxis have used several clinical symptoms (pain, swelling, and trismus) as indicators of infection; however, these clinical symptoms may be vague and unreliable, and cannot be evaluated scientifically. As a result, their use has only sparked more debate in this area of research. The present study assessed the value of routine antibiotic prophylaxis in impacted mandibular third molar surgery using acute-phase protein levels as potential indicators of early and late postoperative infection. Specifically, serum levels of C-reactive protein and alpha-1 antitrypsin were measured preoperatively and postoperatively in patients who received either prophylactic antibiotics or placebos. The results revealed no statistically significant difference between treated and control patients in terms of incidence of postoperative infection.

Analysis of human gingival tissue and gingival crevicular fluid beta-glucuronidase activity in specific periodontal diseases.

BACKGROUND: Beta-glucuronidase (betaG) is one of the enzymes involved in the destruction of non-collagenous components of the extracellular matrix. It is also considered an indicator or predictor of periodontal disease activity. The present study was conducted to determine the presence and the levels of betaG activity in gingival tissue and gingival crevicular fluid (GCF) in periodontal disease and health status. The validity of 2 expressions of data, total betaG activity versus betaG concentration, and the correlations between clinical periodontal status and betaG profile was also evaluated. METHODS: betaG activities in gingival tissues and GCF samples from 57 individuals, divided into 3 equal groups of adult periodontitis (AP), early-onset periodontitis (EOP), and periodontally healthy subjects were spectrophotometrically examined. RESULTS: Both patient groups had higher betaG levels in both gingiva and GCF than controls. Significant differences were observed among all groups when total GCF betaG activities were examined (P <0.05). However, the difference between AP and controls was not significant when concentration values were compared (P >0.05). The highest GCF betaG activity, with both expressions, was detected in EOP group. No absolute correlations between clinical parameters and betaG activity were observed, except for random correlations in the patient groups with mean total betaG activities. Also GCF/gingiva betaG levels and the 2 expressions did not show absolute correlations. CONCLUSIONS: The findings of the present study confirm the relationship between betaG activity and periodontal diseases. The differences in data concerning GCF total betaG activity and betaG concentration may suggest that they are not matching measures. Data presentation seems to be an important factor in GCF/enzyme profile studies.

Effect of accelerated aging on the color stability of cemented laminate veneers.

PURPOSE: The effect of the aging process on color stability of light-cure, dual-cure, and self-cure resin cements used for luting laminate veneers was investigated in this study. MATERIALS AND METHODS: Dyract Cem (self cure), Twinlook (dual cure), and En Force (light cure) cements, 0.30 mm thick, were polymerized on laminate veneers that were 13 mm in diameter and 0.50 mm thick in an A2 shade. Five specimens were made for each material. The specimens were subjected to an accelerated aging process in a Weather-Ometer for 900 hours. Spectrophotometric analyses were made after 300, 600, and 900 hours of accelerated aging time. Overall color difference (delta E*ab) was determined using the CIE-LAB system for measuring small color differences. Chroma changes (delta C*ab) and hue differences (delta H*ab) were also determined. delta E*ab, delta C*ab, and delta H*ab were analyzed by one-way analysis of variance, t test for dependent samples, and Tukey honestly significant difference (HSD) tests. RESULTS: delta E*ab values determined for the materials in this study varied in the acceptable range of 1.9 to 2.7. Different aging times caused no significant differences in delta E*ab, delta C*ab, or delta H*ab values for any of the materials. There were no significant differences in the amount of overall color change among the 3 resin cements at the same aging period. Twinlook material showed the greatest chroma change at each aging time. The greatest hue change was determined for Dyract Cem material. CONCLUSION: The light-cure resin cement tested can be proposed as a suitable material for luting laminate veneers, but long-term clinical studies are necessary to verify these experimental findings.

Surface tension of root canal irrigants.

The aim of this study was to evaluate the surface tension values of established and potential endodontic irrigants to which a surface active agent had not been added. Additionally, Cetredixine, a surfactant-containing 0.2% chlorhexidine gluconate solution, was included in the measurements. Surface tension measurements were performed using the ring method on a DuNouy tensiometer at a standard room temperature. Ringer's solution, saline solution, and distilled water had the highest surface tension values, whereas those of NaOCl (2.5% and 5%) and 17% EDTA were relatively low. Two anesthetic solutions, Ultracaine and Citanest, demonstrated values similar to NaOCl and EDTA, although a statistically significant difference was found between all solutions tested. Cetredixin displayed the lowest surface tension. A low surface tension agent should penetrate tubules better.

Relationship between the quantity of gingival crevicular fluid and clinical periodontal status.

In order to analyze the possible relationship between the quantity of gingival crevicular fluid (GCF) and clinical periodontal status, the severity of gingival inflammation (gingival index (GI) scores) and probing depth (PD) were recorded and GCF samples were obtained from 1,111 sites. These sites were further analyzed on the basis of distinct tooth groups to evaluate the significance of particular anatomical sampling locations. Statistical analysis of cumulative data showed significant increases in GCF volume with greater GI scores and PD. Correlations between GCF volume and both of the clinical measures were also strongly positive and significant for all sites. However, significant differences in GCF volume were observed between the anterior and posterior sampling sites. Increases in volume with increasing GI and PD were more marked for incisor and canine teeth. Similarly, the relationship between the quantity of GCF and clinical periodontal status was more clear and absolute in the anterior region than in the premolar and molar areas. These findings suggest that the quantity of GCF is not constant throughout the entire dentition, and that the relationship between GCF measurements and clinical periodontal status is site-based. This unique feature of GCF seems to be an essential factor in the design of GCF-related studies.

Comparison of two different dose regimens of nedocromil sodium with placebo in the management of childhood asthma.

According to the recent guidelines, persistent asthma requires daily antiinflammatory treatment with either nedocromil sodium, cromolyn sodium or inhaled corticosteroids. In choosing the most appropriate drug, it is wise to weigh the therapeutic advantages against possible side effects, particularly in patients at the milder end of disease spectrum and in children. Cromolyn sodium and nedocromil sodium both have strong safety profiles, and nedocromil sodium has been reported to have a broader spectrum of efficacy than cromolyn sodium. In an attempt to provide data for the efficacy of two different dose regimens of inhaled nedocromil sodium in childhood asthma, a placebo-controlled, randomized, double-blind, double-dummy, parallel group study was conducted in 38 subjects with mild to moderate persistent asthma. After a 2-week run-in period, patients were randomly allocated into one of the three study groups and treated with either placebo or with two times daily (4 mg b.i.d.) or four times daily (4 mg q.i.d.) regimens of inhaled nedocromil sodium for 8 weeks. Symptom scores, bronchodilator requirements, FEV1, daily PEFs and methacholine hyperreactivity were evaluated at study entry, before randomization and at weeks 4 and 8 of treatment. In the four times daily treatment group, slight but significant increases were observed in FEV1, peak expiratory flows and symptom scores (p < 0.05 for each). However, there was no significant change in methacholine hyperreactivity and bronchodilator requirement. In the two times dose regimen and placebo groups, there were no improvements in any of the variables. The compliance, measured as the reduced weight of the canisters, was low, but was not different between the two nedocromil sodium treatment groups. The four times daily regimen of nedocromil sodium was effective in improving control of mild to moderate persistent asthma in children, whereas the two times daily regimen failed.

Relationship between high leukocyte count and cell size in childhood acute myeloblastic leukemia.

In order to determine the significance of cell size together with high leukocyte count (>30x10(9)/L) in acute myeloblastic leukemia (AML), we evaluated the percentages of small, medium and large cells in 33 children with AML. All of the 10 patients with a high leukocyte count and 14 of the 23 patients with a low leukocyte count (<30x10(9)/L) died or experienced a relapse within the first year. The mean small cell percentage of patients with high leukocyte counts was significantly lower than that of patients with low leukocyte counts (p<0.05). The percentages of small, medium and large cells of patients with high leukocyte counts and of patients with low leukocyte counts who died or experienced a relapse within the first year were similar. The percentage of medium cells of patients with high leukocyte counts was significantly higher than that of surviving patients with low leukocyte counts (p<0.05). The mean percentages of small, medium and large cells were similar in patients who died or experienced a relapse and surviving patients with low leukocyte count. We conclude that cell size has prognostic significance when the leukocyte count at admission is over 30x10(9)/L, although confirmation seems necessary with a larger population of patients.

Analysis of gingival crevicular fluid intracytoplasmic enzyme activity in patients with adult periodontitis and rapidly progressive periodontitis. A longitudinal study model with periodontal treatment.

In the present study, the activity of 3 functionally related enzymes, creatine kinase (CK), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST) levels in the rest and flow gingival crevicular fluid (rGCF, fGCF) from patients with rapidly progressive periodontitis (RPP) and adult periodontitis (AP) were determined before and after periodontal treatment, including maintenance. When rGCF and fGCF mean enzyme levels were compared, rGCF was found to contain approximately twice as much enzyme levels than fGCF throughout the study. The findings of the present study revealed that both the rGCF and fGCF samples also contained higher CK, LDH, and AST levels than serum samples. Baseline clinical parameters and GCF enzyme levels presented a significant decline throughout the non-surgical and surgical treatment phases in both patient groups, with surgical treatment being more effective. Despite clinical stability, in the AP group levels of LDH and AST showed a tendency to increase in the third month, while enzyme levels still continued to decrease in the RPP group, who received additional antibiotics during the surgical phase. These findings suggest that GCF intracytoplasmic enzyme profile is related with periodontal status and successful periodontal treatment, in addition to clinical improvement, has a significant effect on this profile. Analysis of biochemical events, more specifically intracytoplasmic enzyme levels in GCF, are likely to offer a sensitive measure of periodontal pathology which may help in overcoming the existing limitations of clinical parameters. For this purpose, analysis of rGCF intracytoplasmic enzymes seems to be more beneficial.

Histopathological evaluation of the tissue reactions to Endo-Fill root canal sealant and filling material in rats.

In this in vivo study, the tissue reactions to silicone-based Endo-Fill root canal filling material were histopathologically evaluated. The reaction of rat connective tissue to polyethylene tube implants that were filled with Endo-Fill were evaluated at 2 days, at 1, 2, 4, and 8 weeks. Four tube were implanted in each rat subcutaneously, and a total of 15 rats were used. Rats were killed, and the specimens were examined under the light microscope (x115 and x230). At the end of 8 wk, a thin fibrous wall with an almost completed advanced healing process was observed around the implant material, but no capsule formation or any inflammatory infiltration was seen.

Comparative neurotoxic effects of root canal filling materials on rat sciatic nerve.

The neurotoxic effects of the root canal filling materials--Endomethasone, N2 Universal, Traitement SPAD, Sealapex, and Calciobiotic Root Canal Sealer (CRCS)--were investigated on isolated rat sciatic nerves after local application. All of the canal filling materials reversibly inhibited the compound action potential (cAP) amplitudes. N2 Universal produced a 50% inhibition in 4.2 +/- 0.2 min. Traitement SPAD, Endomethasone, and CRCS produced the same inhibition in 6.4 +/- 0.3, 6.5 +/- 0.2, and 6.6 +/- 1.1 min, and Sealapex in 9.2 +/- 2.0 min. The inhibitory effect of Sealapex decreased fastest, and 43% recovery of cAP amplitude was observed in 60 to 70 min. The inhibitory effects of Endomethasone, CRCS, and N2 Universal were more pronounced, and 10 to 20% recovery in cAP amplitudes were observed in 2 h. The inhibitory effect of Traitement SPAD was more persistent with 4% recovery in 2.5 h.

Solubilizing efficiency of different gutta-percha solvents: a comparative study.

A study was conducted to comparatively evaluate the efficiency of different solvents for dissolving gutta-percha. Halothane, chloroform, xylene, acetone, isopropyl alcohol, turpentine, oil of mela-leuca and eucalyptol were used as solvents for dissolving standardized gutta-percha discs. Halothane, chloroform and xylene were markedly superior solvents of gutta-percha in comparison with the others. There was no significant difference among the three (p > 0.05). Eucalyptol, turpentine and oil of melaleuca were relatively less efficient. Acetone and isopropyl alcohol did not dissolve gutta-percha, being similar in this respect to distilled water.

Persistence of 99mTc-labelled microorganisms on surfaces of impression materials.

Impression materials or prostheses can be contaminated with oral microflora and provide a significant source for cross-contamination. A study of such contamination was carried out using an approach different from that of infection control, which has often been investigated in previous studies. The study focused on microorganisms known to cause local and systemic diseases and which are normally found in the oral flora. The persistence of Streptococcus mutans (S. mutans), Escherichia coli (E. coli), Staphylococcus aureus and Candida albicans (C. albicans) on zinc-oxide eugenol, silicone rubber, irreversible hydrocolloid and polyether-rubber was investigated using 99mTc-labelled microorganisms. Ten specimens from each of the four impression materials were prepared as discs of 3 mm in height and 10 mm in diameter. After the specimens had been placed into a suspension of 99mTc-labelled microorganisms, remaining radioactivity was counted in a gamma counter. According to own findings, S. mutans was the most, and E. coli the least persistent on the specimen surfaces. The number of microorganisms removed after washing was less than the amount remaining on the surfaces. C. albicans was removed most easily from all impression surfaces that bore persistent microorganisms after washing. Other microorganisms showed various degrees of persistence according to the impression material.