Assessment of damping capacity as an index of root proximity in self-drilling orthodontic mini-implants

Objectives

This study aims to investigate orthodontic mini-implant root proximity, placement torque, and damping capacity and to determine whether placement torque and damping capacity (Periotest value (PTV)) are useful indices for the estimation of mini-implant root proximity.

Materials and methods

The root proximity of 143 orthodontic mini-implants (1.6 mm diameter, 8 mm screw thread length) was evaluated in 79 patients (24 males, 55 females; mean age, 22.5?±?8 years) using cone-beam computed tomography. The placement torque and PTV of each implant were determined using a torque tester and the Periotest, respectively. Variability in these values according to root proximity was evaluated.

Results

PTVs of mini-implants with multiple (two or more) points of contact between the root and implant were significantly larger than those of mini-implants with no root contact in the self-drilling group. Placement torque did not differ significantly according to root proximity. In the self-drilling group, the odds ratio for root contact was 20.82 (P?=?0.000) for a PTV >6.

Conclusions

Placement torque could not be used to estimate root proximity. The PTV was significantly affected by root proximity in the self-drilling group.

Clinical relevance

A threshold of PTV >6 could be applied clinically for the estimation of self-drilling mini-implant root proximity.     

Relationship between nitroglycerine-induced vasodilation and clinical severity of peripheral artery disease

Objective

Nitroglycerine-induced vasodilation is usually used as a control test for flow-mediated vasodilation (FMD). However, nitroglycerine-induced vasodilation per se has also been reported to be impaired in patients with atherosclerosis. The purpose of this study was to determine the relationship between nitroglycerine-induced vasodilation and the clinical severity of peripheral artery disease (PAD).

Methods and results

We measured nitroglycerine-induced vasodilation and FMD in 144 subjects (mean age: 63.8 ± 15.1 years), including 32 PAD patients with critical limb ischemia (CLI group), 28 PAD patients without CLI (non-CLI group), 60 age- and sex-matched patients without established cardiovascular disease (at-risk group), and 24 healthy subjects (healthy group). Nitroglycerine-induced vasodilation was significantly impaired in the CLI group compared to that in the other three groups (healthy group, 16.0 ± 5.3%; at-risk group, 12.9 ± 3.8%; non-CLI group, 10.3 ± 5.1%; CLI group, 6.7 ± 3.9%; P < 0.05, respectively). Even after multivariate adjustment, the differences remained significant. On the other hand, FMD was significantly impaired in the at-risk, non-CLI, and CLI group compared with that in the healthy group (healthy group, 7.1 ± 2.9%; at-risk group, 3.4 ± 2.3%; non-CLI group, 3.5 ± 2.7%; CLI group, 3.0 ± 2.8%; P < 0.001, respectively), but the differences among the at-risk, non-CLI, and CLI groups were not significant. Multivariate analysis revealed that nitroglycerine-induced vasodilation (odds ratio: 0.77, 95% confidence interval [CI]: 0.61–0.97) and diabetes mellitus (odds ratio: 8.75, 95% CI: 1.74–44.2) were independent variables for CLI in PAD patients.

Conclusions

There was no significant difference in FMD between PAD patients with and those without CLI, but nitroglycerine-induced vasodilation was significantly smaller in PAD patients with CLI compared with those without CLI.     

Prognostic value of coronary artery calcium and epicardial adipose tissue assessed by non-contrast cardiac computed tomography

Objective

Epicardial adipose tissue (EAT) accumulation is believed to be associated with development of coronary atherosclerosis. We investigated whether EAT volume as assessed by computed tomography (CT) has value in prediction of future cardiac events.

Methods

We studied 722 patients without proven coronary artery disease (CAD) who underwent non-contrast cardiac CT. EAT volume and coronary artery calcium (CAC) score were measured simultaneously. Patients were followed as to the occurrence of coronary events (cardiac death, nonfatal myocardial infarction, unstable angina requiring hospitalization, and late coronary revascularization ≥3 months after CT examination).

Results

During a 3.7 ± 1.7 years follow-up period, 37 coronary events were documented. Annual event rates increased across CAC score categories (0.3%, 1.0%, 2.4%, and 4.3%, in 0, 1–99, 100–399, and ≥400, respectively, p < 0.001); these were significantly higher in the higher EAT volume group (>median; 107.2 mL, 0.7% vs., 2.1%, adjusted hazard ratio; 2.65, p = 0.0090). Cox-proportional hazard analysis demonstrated that a combination of CAC score ≥ 100 and high EAT volume had a significantly higher event rate than CAC score < 100 and low EAT volume group (adjusted hazard ratio 11.6, p < 0.0001). Using Cox regression models, incremental prognostic values were identified by adding high EAT volume to clinical risks plus CAC score ≥ 100 (global χ², 6.7; p = 0.059).

Conclusion

We suggest that high EAT volume may be an independent predictor of future coronary events and increases predictive values of CAC score in patients without proven CAD.     

The association between changes in lifestyle behaviors and the incidence of chronic kidney disease (CKD) in middle-aged and older men

Background

This study was designed to evaluate whether changes in lifestyle behaviors are correlated with the incidence of chronic kidney disease (CKD).

Influence of Epstein-Barr virus infection in adult T-cell leukemia

The involvement of adult T-cell leukemia (ATL) cells in organs such as the skin and lymph nodes is observed in about 50% of cases of ATL. Epstein-Barr virus (EBV) infection has often been observed in the clinical course of ATL. In this study, we established two B-cell lines from peripheral blood of patients with ATL. EBV DNA, proviral DNA for HTLV-1 and Tax mRNA were detected in both lines. As part of the characterization of these cells, an enhanced expression of intercellular adhesion molecule-1 (ICAM-1) (CD54) or ICAM-3 (ICAM-3) (CD50), lymphocyte function-1 (LFA-1) (CD11a/CD18), and Mac-1 (CD11b/CD18) was observed. To investigate the role of the interaction of these viruses, we transfected EBV and/or HTLV-1 into a healthy donor's lymphocytes, an EBV-infected B cell line, Raji, and a HTLV-1 negative T-cell line, Jurkat. Enhanced expression of adhesion molecules was also observed in double transfectants (EBV and HTLV-1). In the clinical course of ATL, LMP-1, EBNA-2, CD50 and CD54 were detected in lymph nodes and skin specimens by immunohistochemical staining. Furthermore, high levels of interleukin-4 (IL-4) were detected in these cell lines and transfectants. The results indicated that coinfection with HTLV-1 and EBV may induce aggressive organ involvement through the enhanced expression of adhesion molecules via IL-4 signaling. A new mechanism of ATL involvement is discussed.     

Identification of anti-syntaxin 5 autoantibody as a novel serum marker of endometriosis

The sensitivity and specificity of CA125, as a sole serum marker of endometriosis, are not high enough for routine clinical assessment. To explore new markers for the diagnosis of endometriosis, serum autoantibodies in endometriotic patients were investigated employing a fibroblast cell line, two-dimensional (2D) gel electrophoresis and Western blotting. Proteins reacting with serum autoantibodies by Western blotting were identified using MASCOT analysis. ELISAs were then prepared using recombinant proteins and titers of serum autoantibodies were determined in the endometriotic patients, disease controls, and healthy subjects. Among the autoantibodies identified, anti-syntaxin 5 (STX5) autoantibody levels were significantly elevated in endometriotic patients. Sensitivity (53.6%) and accuracy (72.2%) of the serum anti-STX5 autoantibody assay were better than those of serum CA125 levels (36.2% and 62.9%, respectively) for diagnosis. The sensitivity of anti-STX5 autoantibody was remarkably high in Stage II (80.0%) compared with that of CA125 (40.0%). A combination assay of anti-STX5 autoantibody with CA125 improved the overall sensitivity to 69.6%. We conclude that serum anti-STX5 autoantibody, which was discovered by a proteomic approach, is a potential new serum marker for the diagnosis of endometriosis. This initial study now requires validation by further clinical evaluation.     

Increase of child car seat temperature in cars parked in the outpatient parking lot

Background: A guideline for the safe use of child car seats (CS) was published by the Japan Pediatric Society in 2008. There have been few studies of the increase of temperature of a CS in parked cars. The aim of this study was to determine the change in the temperature of the CS in cars parked in full sun. Methods: The temperature of CS was measured during summer (July and August) in 2006, 2007, and 2008. The CS used in this study (n= 50) were for children (≤6 years old) who were taken by car to Sugimura Children's Medical Clinic. Temperatures were only measured on sunny days. Measurements were performed from 09.00 to 17.00 hours. Thermochron (Thermochron i‐Button: G type, Maxim Integrated Products, CA, USA) was used to measure the temperatures. The maximum temperatures of CS were compared in time at the clinic, taking into consideration seat colors, and car colors. Results: Of the 50 cars, three cars were excluded due to being in the shade while the temperature was measured. A total of 47 cars were used for this study. The temperature of the CS ranged from 38.0 to 65.5°C (47.8 ± 5.8°C). Eighteen CS (38.3%) reached a temperature of 50°C or above. The maximum temperature of the 13.00?15.00‐hours group was significantly higher than that of the 09.00?11.00‐hours group (P= 0.035). The CS temperatures in the black car group were significantly higher than those of the white car group (P= 0.013). Conclusion: CS may become very hot while a car is parked in sun, especially if the car and the CS are black, so the CS should be cooled before a young child is placed in it. Guardians of small children should be aware of this risk.     

Twenty-six-week oral toxicity of diheptyl phthalate with special emphasis on its induction of liver proliferative lesions in male F344 rats

The 26-week oral toxicity of diheptyl phthalate (DHP), a peroxisome proliferator-activated receptor α (PPARα) agonist, with special emphasis on the potential induction of hepatocellular proliferative lesions was investigated in this study. DHP was administered to male F344 rats via gavage at 0 (control), 1,000 or 2,000 mg/kg/day for 26 weeks. Body weight gain was significantly lower, whereas food and water consumption was significantly higher in DHP-treated rats compared with controls. DHP-treated rats exhibited decreases in blood triglyceride, total cholesterol, phospholipid and glucose levels, which were likely related to biological effects of the PPARα agonist. Absolute and relative organ weights of the livers with pale brown discoloration and dark brown spots significantly increased in DHP-treated rats. Histopathological examinations revealed remarkable diffuse hypertrophy of hepatocytes with ground-glass appearance, intracytoplasmic inclusion bodies and/or vacuolation in the DHP-treated groups. These findings were associated with increases in serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and γ-glutamyltranspeptidase. The number and area of glutathione S-transferase placental form positive foci, a marker of hepatocellular preneoplastic lesions in rats, significantly increased in DHP-treated groups. Additionally, proliferating cell nuclear antigen positive liver cell counts in DHP-treated groups were significantly higher than those of the controls. Testicular alterations were not detected histopathologically, whereas absolute and relative prostate weights significantly decreased at both doses. These results indicate that DHP induces liver pre-neoplastic foci, and suggest the possibility that DHP is a possible genotoxic carcinogen in the liver of rats.