Radiological evaluation of the use of clay brick and pumice brick as a structural building material.

In this study, clay brick (CBRICK) and pumice brick (PBRICK) samples used as structural material in the construction of dwellings, schools, workplaces and factories in Turkey were compared with each other from a radiological viewpoint. The activity concentrations of 226Ra, 232Th and 40K naturally occurring in CBRICK and PBRICK samples collected from different regions of Turkey were determined by using a gamma-ray spectrometer with a high purity germanium detector (HPGe). The average activity concentrations of 226Ra, 232Th and 40K in CBRICK and PBRICK samples were found as 35.4 ±â€¯3.3, 37.5 ±â€¯2.4 and 593.7 ±â€¯42.7 Bq kg-1 and 81.9 ±â€¯2.5, 65.8 ±â€¯6.0 and 1066.0 ±â€¯46.6 Bq kg-1, respectively. The radon surface exhalation rate (EXS) and radon mass exhalation rate (EXM) of CBRICK and PBRICK samples were measured by using an active radon gas analyzer with an accumulation container. The average value of EXS and EXM of CBRICK and PBRICK samples found as 45.9 ±â€¯2.9 mBq m-2 h-1 and 3.7 ±â€¯2.9 mBq kg-1 h-1 and 100.9 ±â€¯4.7 mBq m-2 h-1 and 9.9 ±â€¯0.5 mBq kg-1 h-1, respectively. Radiological parameters related to external and internal exposure to members of the public such as the radiation protection index, alpha index, and indoor absorbed gamma radiation dose rate and the corresponding annual effective dose from external exposure, annual effective dose from inhalation of radon, and the lifetime cancer risk were estimated for CBRICK and PBRICK samples. The results were compared with each other and with the international recommended limits or criteria. The results reveal that the average values measured and estimated for CBRICK samples are approximately two times lower than those measured and estimated for PBRICK samples. Thus, from the radiological viewpoint, clay brick is preferable to pumice brick as a structural material in the building sector.

Plasma homocysteine level and 677C-->T mutation on the MTHFR gene in patients with venous thromboembolism.

BACKGROUND: The aim of this study was to evaluate the role of plasma total homocysteine level and 677C-->T mutation on the methylenetetrahydrofolate reductase (MTHFR) gene in the development of venous thromboembolism. METHODS: Thirty-six (18 male, 18 female and mean+SD; 48.3 +/- 15.5 years) patients with venous thromboembolism and 25 healthy adults (13 male, 12 female and mean +/- SD; 46.8 +/- 9.2 years) were included in the study. Fasting plasma total homocysteine level was determined by a high performance liquid chromatography. 677C-->T mutation on the MTHFR gene in peripheral blood was detected by Real Time-PCR method. RESULTS: The level of plasma total homocysteine (18.5 +/- 10.6 micromol/L) was significantly higher in patients with venous thromboembolism than in the control group (11.0 +/- 4.7 micromol/L) (p=0.015). 677C-->T mutation on the MTHFR gene heterozygosity was higher in the patient group than in the control group [13 (36.1%) and 2 (8%) respectively] but this difference was not significant (p=0.07). CONCLUSION: It is thought that a high plasma total homocysteine may cause venous thromboembolism (Tab. 2, Ref. 21). Full Text (Free, PDF) www.bmj.sk.

Tuberculosis in patients with end-stage renal disease undergoing dialysis in an endemic region of Turkey.

The incidence of tuberculosis (TB) is high in end-stage renal disease (ESRD) patients undergoing dialysis. Diagnosis is difficult and delayed in this patient group owing to extrapulmonary involvement and nonspecific symptoms. Adverse effects of antituberculosis treatment are seen more frequently in these patients. We retrospectively evaluated the frequency and clinical progression of TB in 18 of 343 dialysis patients diagnosed with TB over a 5-year period at a university hospital in Adana, Turkey. Mean time between initiation of dialysis to diagnosis of TB was 19.5 +/- 26.1 months. Extrapulmonary TB was more frequent (77.8%) than pulmonary TB (22.2%). Diagnosis of TB was made based on clinical data in 1 patient, and microbiologically or pathologically in others. Antituberculosis treatment with 3 or 4 drugs was administered to patients for 6 to 12 months; second-line treatment was initiated in 1 patient infected with multidrug-resistant bacilli. One patient died owing to a cause other than TB; another was lost to follow-up. Adverse effects were hepatotoxicity in 3, optic neuritis in 1, and neuropsychiatric in 3 patients. A clinical response to therapy was achieved in all of the 16 patients who completed treatment. In conclusion, the incidence of TB and the frequency of extrapulmonary involvement are high in dialysis patients. Physicians must be alert to unusual presentations and localizations of the disease; TB must be strongly suspected in endemic regions. Owing to the greater frequency of adverse effects of treatment in these patients, they must be carefully observed during treatment.

Value of the tuberculin skin test in screening for tuberculosis in dialysis patients.

BACKGROUND: Hemodialysis patients are at high risk for tuberculosis, and a tuberculin skin test (TST) is not usually helpful in detecting tuberculosis infection because of anergic reactions. Prophylactic therapy against tuberculosis in dialysis patients is important to enhance transplantation success. Herein we evaluated the value of TST in screening for tuberculosis and analyzed any compounding factors that might affect the results of the test in hemodialysis patients in an endemic area of Turkey. METHODS: A total of 187 (96 female, 91 male) patients were screened using a 2-step TST. Test results were compared with clinical, radiologic, and laboratory data. RESULTS: None of the patients had active tuberculosis during the study and 55% had been vaccinated against tuberculosis. After the first purified protein derivative (PPD) test, 55.1% of the patients showed a positive reaction, ultimately reaching a total of 68.4% following the second test. Cumulative positive TST results were significantly correlated with male gender (P=.001, r=.352), previous tuberculosis history (P=.013, r=.183) positively, whereas with the ferritin level (P=.001, r=-.233) negatively; but there were no significant relationships between TST results and other data. CONCLUSIONS: Impairment of delayed-type hypersensitivity reaction is frequent in dialysis patients, but we observed high rates of positivity with the two-step TST which could be attributed to tuberculosis being endemic in Turkey. Further comparative studies with more specific diagnostic methods will be helpful to evaluate the importance of TST positivity in identifying tuberculosis-infected HD patients.