Effects of impacted maxillary canines on root resorption of lateral incisors

Objectives

The aim of this study was to analyze the amount of root resorption of maxillary lateral incisors by relating the position, location, and angulation of the impacted canine using cone-beam computed tomography (CBCT).

Materials and methods

The study sample consisted of panoramic and CBCT radiographs of 46 patients with a unilateral impacted canine (16 males and 30 females; mean age: 19.53 ± 6.66 and 19.44 ± 5.77 years, respectively). Sector location and canine angulation were measured in panoramics. All tomographs were obtained using CBCT (NewTom 5G, QR, Verona, Italy) and three-dimensional (3D) reconstructions of the maxillary laterals assessed by Mimics 14.01 image analysis software.

Results

Upper lateral incisor volume was smaller on the impacted side (401.95 ± 83.69 mm³) than on the nonimpacted side (433.54 ± 92.6 mm³, P < 0.05). There were no significant differences of lateral root resorption volume when comparing the impacted canines being on the labial or palatal sides (P > 0.05), but impacted canine angulation was significantly steeper on the labial side (70.85°) than on the palatal side (46.09°, P < 0.05). The volume of root resorption of laterals when comparing the various positions of the canine in different sectors or canine angulation in 30^o intervals was not statistically significantly different (P > 0.05).

Conclusions

The impacted canines caused root resorption of lateral incisors. The angulation of the canine was steeper on the labial side than on the palatal side but root resorption of adjacent laterals was not different. There were no statistically significant differences in the amount of root resorption of the laterals when the canine was evaluated according to localization and angulation.

     

Left Ventricular Dyssynchrony and Its Effects on Cardiac Function in Patients with Newly Diagnosed Hypertension

Objectives: Left ventricular (LV) systolic synchrony, defined as simultaneous peak contractions of corresponding cardiac segments, is well documented to be impaired in hypertension but its effect on LV function is not clear. The aim of this study was to assess the impacts of LV systolic dyssynchrony on LV function in newly diagnosed hypertensives. Methods: Forty-eight newly diagnosed hypertensive patients and 33 controls were enrolled. All study population underwent a comprehensive echocardiographic evaluation including tissue synchrony imaging. The time to regional peak systolic tissue velocity (Ts) in LV by 12 segmental models was measured and two parameters of systolic dyssynchrony were computed. Results: Baseline demographic characteristics were similar in both study groups. Dyssynchrony parameters prolonged in newly diagnosed hypertensive patients compared to controls: the standard deviation (SD) of 12 LV segments Ts (40.2 ± 21 vs. 26.2 ± 13.4, P = 0.003); the maximal difference in Ts between any 2 of 12 LV segments (123.3 ± 61.5 vs. 79.8 ± 37.9, P = 0.001). In multivariable analysis, Ts-SD-12 was found to be an independent predictor for systolic function (β=-0.29, P = 0.008). But, both diastolic and global functions were not independently related to Ts-SD-12. Conclusion: LV synchronization is impaired in newly diagnosed hypertensive patients. LV dyssynchrony is one of the independent predictors of systolic function in hypertensive patients.     

Patent Foramen Ovale among Patients with Mild Chronic Obstructive Pulmonary Disease and Unexplained Hypoxia

Purpose: To evaluate whether patent foramen ovale (PFO) is a contributing factor to hypoxia in patients with chronic obstructive pulmonary disease (COPD). Methods: Twenty‐one patients over 40 years of age with mild COPD (Forced expiratory volume (FEV1)/Forced Vital Capacity (FVC): > 50%) who had hypoxia (PO₂ < 80 mmHg, SaO₂ < 95%) that could not be explained by COPD alone were included in this study. Arterial oxygen pressures (PO₂) and arterial oxygen saturations (SaO₂) were recorded from laboratory evaluations of arterial blood gases. Respiratory function tests were performed to analyze the degree of COPD. Standard and contrast echocardiography was used to calculate pulmonary artery pressure (PAP) levels and to determine patients with a PFO. Results: The mean age of the patients was 64 ± 12 years. Four patients (19%) had a PFO. The mean PO₂, mean SaO₂, and mean PAP levels were 57.4 ± 6.8 mmHg, 90 ± 3.2%, and 33.8 ± 5.4 mmHg, respectively, in patients without PFO. The mean PO₂, mean SaO₂, and mean PAP levels were 46.5 ± 13.7 mmHg, 79.3 ± 12.8%, and 42.5 ± 6.5 mmHg, respectively, in patients with PFO. There were no statistically significant differences noted between the two groups in the PO₂ levels (P = 0.172) and SaO₂ levels (P = 0.065). A comparison of the PAP levels revealed a statistically significant difference between the two groups, with values that were more elevated in the PFO group than in the non‐PFO group (P = 0.031). Conclusion: This study demonstrated that PFO is not a contributing factor to deep hypoxia in COPD patients with lower PO₂ and SaO₂ levels; however, higher PAP levels were detected in patients with a PFO. Further studies involving a larger number of patients are needed to be conclusive. (Echocardiography 2010;27:687‐690)     

MEFV mutations in familial Mediterranean fever: association of M694V homozygosity with arthritis

Objective Familial Mediterranean fever (FMF) is an autosomal recessive recurrent polyserositis with a higher prevalence in some ethnic groups, including Turks. Mutations in the FMF gene (MEFV) were found associated with FMF. The aim of this study was to analyze MEFV gene mutations in FMF patients to gain insight into the mutation phenotype correlation.Objectives We analyzed the most frequent mutations (M680I, M694V, V726A, and E148Q) in a group of young male Turkish FMF patients using an amplification refractory mutation system and a commercial kit.Results M694V mutation was detected in 80% of the patients. After making a strict diagnostic discrimination between arthralgia and arthritis, arthritis was present in 71% of homozygous and 29.4% of heterozygous patients for M694V mutation. Other mutations were not found to correlate with specific symptoms or findings.Conclusion The homozygosity of M694V mutation in the MEFV gene is associated with arthritis in FMF patients.     

Poor efficacy of ranitidine bismuth citrate-based triple therapies for Helicobacter pylori eradication.

BACKGROUND: Helicobacter pylori eradication rates have tended to decrease recently possibly related with increasing antibiotic resistance. The present study investigated the efficacy of three different ranitidine bismuth citrate (RBC) based triple regimens in a population with high prevalence of H. pylori. METHODS: 300 consecutive H. pylori positive patients with non-ulcer dyspepsia were randomized into three regimens: (1) RBC 400 mg, amoxicillin 1000 mg and tetracycline 500 mg [RBC-AT], (2) RBC 400 mg, amoxicillin 1000 mg and clarithromycin 500 mg [RBC-AC], (3) RBC 400 mg, metronidazole 500 mg and tetracycline 500 mg [RBC-MT]. Tetracycline was given q.i.d, all other drugs were given b.i.d. for 14 days. Gastroscopy and (14)C-Urea breath test (UBT) were performed before enrollment and UBT only was repeated 6 weeks after the end of treatment. RESULTS: 274 patients completed the protocols. The overall 'intention to treat' and 'per protocol' H. pylori eradication rates in all subjects were 57.6% (95% CI: 52-63) and 63.1% (95% CI: 57-68), respectively. The eradication rates achieved in the groups (RBC-AT, RBC-AC and RBC-MT) were 64.4% (95% CI: 54-74), 66.2% (95% CI: 56-76), and 58.9% (95% CI: 49-68) on 'per protocol' analyses, respectively. There was no difference in eradication rates, compliance and major side effects between the groups. CONCLUSION: The current RBC-based H. pylori eradication therapy is not adequately effective.     

Niche adaptation and genome expansion in the chlorophyll d-producing cyanobacterium Acaryochloris marina

Acaryochloris marina is a unique cyanobacterium that is able to produce chlorophyll d as its primary photosynthetic pigment and thus efficiently use far-red light for photosynthesis. Acaryochloris species have been isolated from marine environments in association with other oxygenic phototrophs, which may have driven the niche-filling introduction of chlorophyll d. To investigate these unique adaptations, we have sequenced the complete genome of A. marina. The DNA content of A. marina is composed of 8.3 million base pairs, which is among the largest bacterial genomes sequenced thus far. This large array of genomic data is distributed into nine single-copy plasmids that code for >25% of the putative ORFs. Heavy duplication of genes related to DNA repair and recombination (primarily recA) and transposable elements could account for genetic mobility and genome expansion. We discuss points of interest for the biosynthesis of the unusual pigments chlorophyll d and α-carotene and genes responsible for previously studied phycobilin aggregates. Our analysis also reveals that A. marina carries a unique complement of genes for these phycobiliproteins in relation to those coding for antenna proteins related to those in Prochlorococcus species. The global replacement of major photosynthetic pigments appears to have incurred only minimal specializations in reaction center proteins to accommodate these alternate pigments. These features clearly show that the genus Acaryochloris is a fitting candidate for understanding genome expansion, gene acquisition, ecological adaptation, and photosystem modification in the cyanobacteria.