ABSTRACT
Objective: To investigate the prevalence of non-tuberculosis mycobacteria (NTM) among the samples deposited from the National Tuberculosis Reference Laboratory of Iran between 2011 and 2018. Methods: The study evaluated the prevalence of NTM among specimens from patients with pulmonary tuberculosis symptoms (n=15 771) deposited at the National Tuberculosis Reference Laboratory of Iran from 2011 to 2018. Detection of Mycobacterium (M.) tuberculosis was based on presence of a 190-bp amplicon from IS6110 insertion sequence using Tb1 and Tb2 primers, and amplicon-negative specimens were tested for NTM and M. tuberculosis (refractory to IS6110 amplification) using restriction fragment length polymorphism PCR of hsp65 amplicon fragment. Results: A total of 7 307 (46.33%) M. tuberculosis and 658 (4.17%) NTM specimens were found, the latter mainly comprising M. abscessus (10.18%), M. avium (2.28%), M. chelonae (8.97%), M. intracellulare (10.49%), M. kansasii (4.71%), and M. simiae (56.08%). Conclusions: As treatment for NTM differs from that for M. tuberculosis, accurate detection of Mycobacterium sp. is of public health significance.
ABSTRACT
Mycobacterium tuberculosis has infected more than two billion individuals worldwide, of whom 5%–10% have clinically active disease and 90%–95% remain in the latent stage with a reservoir of viable bacteria in the macrophages for extended periods of time. The tubercle bacilli at this stage are usually called dormant, non-viable, and/or non-culturable microorganisms. The patients with latent bacilli will not have clinical pictures and are not infectious. The infections in about 2%–23% of the patients with latent status become reactivated for various reasons such as cancer, human immunodeficiency virus infection, diabetes, and/or aging. Many studies have examined the mechanisms involved in the latent state of Mycobacterium and showed that latency modified the expression of many genes. Therefore, several mechanisms will change in this bacterium. Hence, this study aimed to briefly examine the genes involved in the latent state as well as the changes that are caused by Mycobacterium tuberculosis. The study also evaluated the relationship between the functions of these genes.
ABSTRACT
Cartilage has a poor regenerative potential with very low cell-density that contributes to its poor capability for self-repair .For this reason, autologous cartilage grafts have been used in reconstructive surgery .Today; the rapidly emerging field of tissue engineering holds great promises for the generation of functional cartilage tissue substitutes. The technique was initiated by harvesting cartilage cells [chondrocytes] from a donor site such as the nasal septum or the auricle. However, in clinical use of human chondrocytes for tissue engineering, extensive expansion of cell numbers from a small donor site biopsy was required and this could limit the chondrogenic potential of cells after proliferation. Therefore, the ability of chondrocytes to replicate in- vitro allowed the expansion of cell numbers to produce theoretically limitless supplies of cartilage autografts .Stem cell technology presents an alternative, immunoprivileged resource of cells with unlimited replicative capacity. These cells exist in a wide selection of tissues and provide the option of multi-lineage differentiation. This paper reviews the current evidence that stem cells may provide a superior cell resource for tissue engineered cartilage and outlines the methodology for their isolation and chondrogenic induction
Subject(s)
Chondrogenesis , Stem CellsABSTRACT
Background: While considering the rise in the mean age of the chronic renal failure [CRF] patients and increasing frequency of those who need constant hemodialysis, the creation of a native arteriovenous fistula [AVF] is not possible, which could be due to the inaccessibility of the superficial veins. This study was conducted to evaluate the efficacy of the vascular access, using cryopreserved jugular vein
Materials and Methods: In this experimental study, 15 sheep [Wt.= 30-40 kg] were selected between the year 2001 and 2002. The external jugular vein of each sheep was excised and after cryopreservation was put in liquid nitrogen [-196°C]. Twenty-eight days later, the sample veins were used as allograft [in another sheep], and autograft [in the same sheep] and were placed between carotid artery and external jugular vein as bridge AVF. The efficacy, function, and patency were evaluated using doppler sonography and pathologic report
Results: Patency rate of sample was 100% after 3 months in both allografts and autografts. Thrombosis, hematoma, and infection were not seen. No inflammation was detected in pathologic report
Conclusion: This study showed that using allograft vein for vascular access is feasible and suitable, and it is recommended specially for those with previously infected fistula