Molecular epidemiology and drug resistance of Mycobacterium tuberculosis in a tertiary care hospital in northeastern Mexico.

INTRODUCTION: Tuberculosis (TB) is a re-emerging disease considered a public health concern. In the present study, we analyzed the epidemiology and drug resistance of Mycobacterium tuberculosis strains isolated from patients with pulmonary TB. METHODOLOGY: Mycobacterium tuberculosis isolates (n = 190) were obtained from patients with pulmonary TB admitted to Dr. José Eleuterio González University Hospital (UH). Each M. tuberculosis isolate was analyzed by spoligotyping (spacer oligonucleotide typing) and MIRU-VNTR (Mycobacterial Interspersed Repetitive Units-Variable Number Tandem Repeat). Drug resistance was evaluated using the Anyplex™ II MTB/MDR/XDR assay. RESULTS: The predominant spoligotypes observed were X1 (SIT 119, n = 46), T1 (SIT 53, n = 40), H3 (SIT 50, n = 13), Beijing (SIT 1, n = 11), and EAI2-Manila (SIT 19, n = 8). MIRU-VNTR analysis showed that the locus QUB-26 had the highest allelic variability. The observed drug resistance included monoresistance to rifampicin (2.6%; n = 5), isoniazid (3.2%; n = 6), and fluoroquinolones (1.6%; n = 3) as well as multidrug resistance (5.3%; n = 10). All of the Beijing strains were susceptible. Regarding comorbidities, 13.7% (26/190) of the patients were co-infected with TB and HIV (TB+HIV+), and 31.6% (55/190) had TB along with diabetes (TB + diabetes). CONCLUSIONS: The most prevalent lineages were X1 (SIT 119; 24.3%) and T1 (SIT 53; 21%). An alarming proportion (12.6%) of M. tuberculosis isolates presented drug resistance. To effectively manage TB, continuous surveillance of regional strain dissemination, drug resistance profiles, and TB-associated comorbidities is crucial.

shRNA-WT1 Potentiates Anticancer Effects of Gemcitabine and Cisplatin Against B16F10 Lung Metastases In Vitro and In Vivo.

BACKGROUND/AIM: High expression level of Wilm's tumor gene (WT1) in several types of tumors appears to confer disruption of apoptosis and resistance to chemotherapeutic drugs, and correlate with poor outcome. The aim of this work was to determine if down-regulation of WT1 expression results in decreased cell proliferation and the increased action of different types of drugs, both in vitro in B16F10 cells, and in vivo in C57BL/6 mice. MATERIALS AND METHODS: Inhibition of cell proliferation by short hairpin RNA against WT1 (shRNA-WT1), cisplatin, and gemcitabine in B16F10 cells in vitro was determined by the MTT assay and analysis of clonogenic survival. The apoptosis rate was determined by flow cytometry for annexin-V- fluorescein isothiocyante and propidium iodide. RESULTS: Compared to treatment with shRNA-WT1 alone, treatment with shRNA-WT1 in combination with drugs had a synergistic inhibitory effect on B16F10 cell proliferation, particularly for the combination of cisplatin and gemcitabine at their 25% cytotoxic concentrations in vitro. Furthermore, mice treated with shRNA-WT1 in combination with cisplatin and gemcitabine were protected in the same way as those treated with the drugs alone, but were in better physical condition. CONCLUSION: Decreased WT1 expression induces cell death and potentiates the action of anticancer drugs by inducing synergistic effects both in vitro and in vivo, which may be an attractive strategy in lung cancer therapy.