Acute wood or coal exposure with carbon monoxide intoxication induces sister chromatid exchange

OBJECTIVE: The object of this study was to investigate the genotoxic effect of acute overexposure to combustion products originating from coal or wood stoves in patients presenting with acute carbon monoxide intoxication. STUDY DESIGN: In a prospective study, we analyzed the frequency of sister chromatid exchange and the carboxyhemoglobin concentration in 20 consecutive patients without a history of smoking or drug use who had been treated in the Emergency Care Unit of Istanbul Medical Faculty due to acute carbon monoxide intoxication. All of these cases were domestic accidents due to dysfunctioning coal or wood stoves. The results were compared with a control group of 20 nonsmoking, nondrug-using healthy individuals matched for age, sex, and absence of other chemical exposure. RESULTS: The mean sister chromatid exchange frequency per metaphase was significantly higher in the study group compared to the control group: 8.11 +/- 2.39 vs. 6.33 +/- 1.60 (p = 0.008). We found that there was no positive correlation between the blood carboxyhemoglobin concentration and sister chromatid exchange frequency. CONCLUSIONS: These results suggest that acute exposure to combustion products of wood or coal is genotoxic to DNA. Potential causes of genotoxicity include known mutagenic compounds present in coal or wood smoke and ash, oxygen radicals formed during combustion, as well as hypoxic and reperfusion injury mechanisms initiated by carbon monoxide intoxication. Additional studies on separate carbon monoxide exposure from smoke and ash are needed to understand individual genotoxic contributions and mechanisms.     

Multidimensional assessment of voice and speech after supracricoid laryngectomy with cricohyoidopexy

This study was designed: to evaluate the vocal function in the patients with supracricoid laryngectomy (SCL) compared with normal subjects; to determine the factors affecting voice (such as number of arytenoid(s) preserved and movement of larynx and tongue base); and to determine the correlations between videolaryngostroboscopy, acoustic and perceptual parameters. Ten patients who underwent SCL with cricohyoidopexy for primary laryngeal squamous cell carcinoma were included into the study. Vocal function was investigated by means or videolaryngostroboscopy. Voice quality was assessed by means of objective acoustic analysis and subjective perceptual ratings by trained raters. Aberrant, incompetent, and rough mucosal wave was observed in the anterior and superior surfaces of arytenoids(s), the inferior part of tongue base and the lateral walls of the hypopharynx. The acoustic parameters were found to be significantly different from those of normal subjects. The values of perceptual scores were approximately within 50 per cent of normal range. The number of arytenoids spared did not affect acoustic or perceptual measurements. A rough, breathy, unpleasant but intelligible and acceptable voice could be obtained after SCL with cricohyoidopexy.     

Tensile strength of type IV dental stones dried in a microwave oven

STATEMENT OF PROBLEM: It is known that drying dental stones in a microwave oven can save time, but the strength of the material may be affected by different drying methods. PURPOSE: This study evaluated the diametral tensile strength (DTS) of 5 type IV gypsum products at different time intervals using microwave and air-drying methods. MATERIAL AND METHOD:. A total of 300 cylinder specimens were prepared from 5 type IV dental stones (Moldano, Amberok, Herastone, Shera-Sockel, and Fujirock; n = 60 per stone) in accordance with the manufacturers' recommendations. Half of the specimens of each stone (n = 30) were dried in open air within a temperature range of 20 +/- 2 degrees C; the other half (n = 30) underwent initial setting in a silicone rubber mold in open air for 10 minutes and then were dried in a microwave oven for 10 minutes. Within these groups, 10 specimens were tested under diametral compression at each of the following time periods: 30, 60, and 120 minutes after drying. Three-way analysis of variance and Scheffe's post hoc test were performed for statistical comparisons at a significance level of P<.05. RESULTS: At all time intervals, the diametral tensile strength values for dental stones dried in a microwave oven (mean 2.99 MPa) were significantly higher (P<.01) than the values for specimens dried in open air (mean 2.53 MPa). CONCLUSION: Within the limitations of this study, microwave oven drying had a positive effect on the diametral tensile strength of 5 type IV dental stones.     

The effectiveness of thrombolytic therapy in patients with massive and submassive pulmonary thromboembolism

Thrombolytic therapy is the most effective therapy for massive pulmonary embolism (PTE). In this study we evaluated the symptoms, clinical and radiologic features and response to thrombolytic therapy in patients who had massive or submassive PTE. Thrombolytic therapy was administered for a mean period of 3 (1-5) hours to 19 patients with a mean age of 63.7 years who had the diagnosis of PTE based on symptoms which lasted for an average of 72 (2-240) hours and findings of echocardiography, spiral computed tomography (CT) angiography and perfusion scan. The patients to whom heparin infusion and oral anticoagulant treatment were given after thrombolytic therapy were evaluated. Bleeding as a complication was noted in six patients after thrombolytic therapy. Two patients died due to this complication. Control spiral CT angiography was performed to 12 of 15 (80%) patients who were initially diagnosed PTE by spiral CT angiography. While marked regression was noted in 5 (41.7%) patients in the early phase (second week), in 7 (58.3%) patients in the late phase (sixth month) PTE findings were completely disappeared. The median value of pulmonary artery pressure was 65 (45-70) mmHg before and 39.5 (30-45) mmHg after the treatment. Of the genetic factors studied before thrombolytic therapy, antithrombin III deficiency was found as the most common one. This study demonstrates that spiral thorax CT angiography is a very accurate diagnostic tool for the definitive diagnosis and transthoracic echocardiography is very useful for the rapid diagnosis and to decide for thrombolytic therapy, in especially patients who are not hypotensive and have submassive to massive PTE, and support the idea that thrombolytic therapy is life saving after reaching the certain diagnosis.     

Cramp finding: can it be used as a new diagnostic and prognostic factor in lumbar disc surgery?

In this prospective study, the validity and the importance of a new finding (cramp finding) in the diagnosis and outcome after lumbar disc surgery were tested. The test is performed with the person in prone position. Against a forceful knee flexion, the examiner holds the leg with one hand and applies a force to overcome the knee flexion. The finding is positive if the examined person feels a disturbing cramp in the leg or thigh. The study was performed between October 1997 and December 1999. Besides the cramp finding, the classical disc herniation examination, including mechanical and neurological findings, magnetic resonance (MR) imaging tests, and laboratory findings were checked pre- and postoperatively. The positive cramp finding in the operated group was 72% (n=133) preoperatively and straight leg raising (SLR) test was positive in all of them. Cramp finding was positive in 70%, 52%, 34%, and 8% of patients postoperatively in the first, 3rd, 12th and 24th months, respectively. The presented finding appears to be as valuable as the SLR, and especially contralateral SLR, tests in lumbar disc surgery. Cramp finding is also important in outcome evaluation.     

Two-year follow-up of a patient with oligodontia treated with implant- and tooth-supported fixed partial dentures: a case report

Dental implants have become an accepted treatment modality for aging patients with either completely or partially edentulous arches. However, growing patients with congenitally missing primary and/or permanent teeth often need dental implant treatment, even before puberty, for optimum functional and/or psychosocial development. From a developmental perspective, dental implants cannot accompany the physiologic differentiation of the alveolar bone because of the difference in anchorage between an osseointegrated dental implant and a tooth in bone. Nevertheless, reports in the literature suggest that dental implants can be used successfully in partially and completely edentulous arches affected by congenital disorders such as ectodermal dysplasia. In this case report, a multidisciplinary team approach, which included an orthodontist, an oral surgeon, and prosthodontists, in the treatment of a patient with oligodontia is discussed. The orthodontic and prosthodontic treatment sequence, growth analysis from age 14 to 18 years, and successful therapy of an implant associated with late failure is presented.