Isolation and identification of nontuberculous mycobacteria from specimens of lower respiratory tract of transplanted patients based on the evaluation of 16SrRNA gene

BACKGROUND

Nontuberculous mycobacteria are pervasive microorganisms and are often present as saprophytes in humans, animals, and the environment. Today, these bacteria are known as the most important environmental opportunists and, in the last decades, infections by nontuberculous mycobacteria have multiplied, due to increased immunodeficiency (cancer, transplant recipients, HIV).

STUDY DESIGN

This study aimed to investigate the infections by nontuberculous mycobacteria in transplanted patients.

METHODS

The study was performed on 57 samples from respiratory secretions of transplant recipients taken by standard methods. Nontuberculous mycobacteria were identified by culture method and molecular identities of clinical isolates were investigated by PCR amplification using 16SrRNA gene and sequence analysis and Blast of the sequences. Demographic data were evaluated by Spss software.

RESULTS

The prevalence of nontuberculous mycobacteria in transplant patients was 22.8%, the age of patients was between 23 and 52 years. The most common involvement of nontuberculous mycobacteria in our transplanted individuals were 6 strains of M avium-intracellulare Complex (42.87%), followed by 2 strains of M marinum (14.29%) and 1 strain each (7.14%) of M xenopi, M chelonae, M intracellulare, M kansasii, M simiae. At the conclusion of the tests, one final strain was identified as M tuberculosis (7.14%).

CONCLUSION

The prevalence of nontuberculous mycobacteria indicates their importance in the fate of these patients. The identification of nontuberculous mycobacteria is a neglected part of microbiology laboratories, due to the lack of sufficient facilities and the risk associated with their culture. Therefore developing routine methods for the identification of these infections appears to be critical, especially in hospitals with the transplantation ward.

Evaluation of Copper, Zinc, Cu/Zn, and VEGF in Patients with AML in Iran

BACKGROUND

Copper and zinc are the elements with numerous physiological activities. Copper (Cu) has an important role in angiogenesis and acts by increasing Vascular Endothelial Growth Factor (VEGF). Serum levels of copper will be increased in cancer incidence, progression and recurrence. The aim of this study was to measure blood levels of copper, zinc, and the ratio of Cu /Zn, as well as VEGF levels before and after treatment of acute myeloid leukemia.

METHODS

Thirty patients who were recently diagnosed with Acute Myeloblastic Leukemia (AML) in Shahid Ghazi Tabatabai oncology hospital enrolled in this clinical trial. On the first day, blood samples were taken for copper, zinc, and VEGF assay and flowcytometry. Treatment protocol was (7×3) regimen. Blood samples were collected for evaluation of copper, zinc, and VEGF. They were sent to Biochemistry Laboratory in medicine faculty for analysis.

RESULTS

Amongst 30 AML patients, 14 (46.7%) were female and 16 (53.3%) were male. Patients of various ages ranged from 16 to 53 years, with a median age of 9.1±9.35 years. The mean serum level of copper, zinc, and mean Cu/Zn ratio before and after treatment showed significant difference (p<0.05) There was also significant difference between the mean VEGF level before and after treatment (p<0.05).

CONCLUSION

This study reveals that there is no significant relationship between copper, zinc serum levels, their ratio, and VEGF in AML patients. We hypothesize that increased serum copper is associated with increase of VEGF levels which can indicate the impact of copper in malignancies including AML.

Carbenoxolone induces apoptosis and inhibits survivin and survivin-ΔEx3 genes expression in human leukemia K562 cells

BACKGROUND AND THE PURPOSE OF THE STUDY

Leukemia is a malignant disorder of the blood progenitor/stem cells which is characterized by abnormal proliferation of white blood cells. Although anti-cancer drugs induce apoptosis in cancerous cells, drug resistance is the significant problem mainly due to over-expression of inhibitors of apoptosis proteins (IAPs) such as survivin. In this content, it has been reported that an anti-inflammatory drug, Carbenoxolone (CBX), could induce apoptosis and growth inhibition in several types of cancerous cells. In the present study, effects of CBX on apoptosis and level of the expression of survivin gene and its ΔEx3 splicing variant have were evaluated in K562 cells.

METHODS

K562 cells were cultured and treated with different concentrations of CBX (50-300 µM) at different time intervals (12-48 hrs). Trypan blue exclusion test was used to evaluate cell viability. Fluorescent microscopy (Acridine Orange/Ethidium Bromide double staining) and DNA fragmentation assay were used to study apoptosis. The expression level of survivin and its ΔEx3 splice variant were studied by RT-PCR.

RESULTS AND MAJOR CONCLUSION

It was found that both growth inhibition and apoptosis occurred in K562 cells. In addition, down-regulation of survivin and survin-ΔEx3 were observed, after 2-4 hrs treatment with 150 µM of CBX. However, the expression level of survivin and its ΔEx3 splice variant increased in subsequent time (6-12 hrs) nearly to the level of control cells. From the results of this study, it may be concluded that CBX can be considered as a candidate for further studies in CML treatment, especially in the case of drug-resistant leukemia cells.

Effects of iodized salt consumption on goiter prevalence in Isfahan: the possible role of goitrogens

OBJECTIVE

To evaluate the success of the Iranian Iodine Deficiency Disorders Committee in achieving World Health Organization (WHO) goals for reducing the prevalence of goiter in children by adding iodine to table salt beginning in 1989.

METHODS

In 1997, 8,000 male and female 6- to 18-year-old students were selected by cluster sampling in schools of Isfahan. Their thyroids were examined by four endocrinologists, and goiter was staged on the basis of the WHO classification. As an index of iodine consumption, urinary iodine concentrations were measured in 3,000 students.

RESULTS

Goiter was observed in 62% of the students. Of the overall study group, 94% had sufficient iodine consumption (urinary iodine concentration of 10.0 microg/dL or more). Of those students who had sufficient iodine intake, 63.2% had goiter. Of the 6% of students with iodine deficiency, 5% had mild, 0.9% had moderate, and only 0.1% had severe iodine deficiency. Goiter was absent in half of the students with severe iodine deficiency. The prevalence of goiter in 6- to 10-year-old children was 65%.

CONCLUSION

Despite sufficient iodine intake, the prevalence of goiter is still high in Isfahan City. Apparently, either this high prevalence has no relationship to iodine deficiency and possibly other unknown goitrogens are involved in the pathogenesis of goiter in Isfahan or the period of iodine intake has been too brief to affect thyroid sizes. Inasmuch as goiter prevalence is also high in the 6- to 10-year-old children, who have had iodized salt available for most of their lives, the second option is less probable. Another possibility is an increased rate of autoimmune thyroid diseases (because of iodine repletion) that resemble goiter during their early stages.