TANAFFOS
Year:2005 | Volume:4 | Issue:14|Papers Count:9

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.

Background: Maximal respiratory pressures are suitable for non –invasive evaluation of respiratory muscle function A variety of methods for subject selection and test procedures have been used for the determination of normal values and reference equations for maximal respiratory pressure (MRP). Materials and Methods: we analyzed a well-defined, healthy subgroup of 224 men and 211 women with a wide age range (20 to 82 yr), using multiple linear regression, for the purpose of determining the effect of age, other correlates, normal values, and gender-specific reference equations on MRP. Results: Mean values of maximal inspiratory pressure (MIP) were 9.78 kPa for men and 7.61 kPa for women. Mean values of maximal expiratory pressure (MEP) were 13.11kPa for men and 10.21 kPa for women. Conclusion: Prediction equations and mean value normally resulted from a cohort study of healthy 20-82 yrs subjects are given and are recommended to be used by pulmonary function laboratories in IRAN.

Background: Synthetic fibers of rockwool are deciphered from Basalt stone. Chemical, physical and biological similarities with asbestos detain scientists to consider effects and complications caused by rockwool in lung. This historical cohort research was designed to state impact of rockwool on radiographic findings of lung and its spirometric changes. Materials and Methods: Encountered group, “Iran Rockwool Factory” was selected by simple random sampling technique and matched with comparison group, “Minoo Confectionery Factory”, regarding age and cigarette smoking. Medical and occupational histories, clinical examinations and all spirometries were carried out in health centers of the two factories. Chest x- ray was taken for all subjects of the two groups. All data were gathered and registered in designed questionnaires. Results: Although a significant discrepancy existed in dyspnea, non cardiac chest pain and wheeze, there was not any statistically significant difference in radiographic findings and spirometric parameters between the two groups. Conclusion: We do not have enough evidence to support the adverse effects of rockwool on respiratory function and significant observable radiographic changes in chest x-ray.

Background: This study was conducted to compare the sedative and hemodynamic effects of morphine and remifentanil in traumatized patients requiring intubation and mechanical ventilation in intensive care unit of Rasool Akram Hospital, Iran University of Medical science during the years 2003-4. Material and Methods: This was a randomized controlled clinical trial study in which all traumatized patients requiring mechanical ventilation in ICU were randomly enrolled into two groups. The first group was given a 5 mg bolus dose of morphine and the second group received an infusion of remifentanil starting with 0.05 μgr/kg and the doses were sequentially increased to reach a sedation state of 3-4 according to Ramsey scale. The regimen was continued for 24 hours, during which blood pressure, heart rate, and respiratory rate was monitored. Data were analyzed using SPSS software version 11.5. Results: A total of 60 patients aged 18-80 yrs with mean age of 42.53 ±18.5 yrs, consisting of 37 (61.7%) males and 23 (38.3%) females entered the study. The mean blood pressure was 109.12±1.68 mmHg in the morphine group and 90.01 ±6.66 mmHg in the remifentanil group (p<0.00). The mean heart rate of the aforementioned groups were 101.89 ±2.31 and 95.06±10.15 ( p<0.00) respectively. Conclusion: Remifentanil causes an initial decline in blood pressure but it maintains the pressure in a rather steady state during the period of infusion. This result was quite similar to that of morphine with the additional fact that there was no profound decline of blood pressure with morphine.

Background: Tuberculosis is a major health problem in Saudi Arabia and developing countries. Understanding the epidemiology of the disease helps in its early identification and prevention. This study was conducted to evaluate the pattern and clinical presentation of Mycobacterium tuberculosis (MTB) among Saudi nationals. Materials and Methods: We reviewed the clinical and laboratory records of 147 patients with proven cultural diagnosis of MTB attending King Khalid National Guard Hospital (KKNGH), Jeddah, Saudi Arabia between June 1993 and June 1999 and also studied the symptoms and clinical pattern of the disease. Results: Our study demonstrated that MTB affected mainly young adults in their second and third decades. There was no significant difference in the prevalence of the disease between the genders, though slightly more males (75/147, 51%) were affected compared to females (72/147, 49%). There was a high incidence of extra-pulmonary TB (36.6%), with lymph node involvement being the most common extra-pulmonary site (27%). Although the most common symptoms were chronic cough (51.7%), fever (46.3%) and weight loss (41.5%), these symptoms seem to occur less frequently in patients with TB than previously reported. There was an alarming high prevalence of drug resistant MTB (15% for isoniazid, 9.5% for rifampicin, 8.2% for pyrazinamide, 15.6% for ethambutol, and 9.5% for multi-drug resistant). Conclusion: The presence of classical symptoms of MTB (cough, fever, weight loss) was less frequent than expected suggesting atypical presentation of the disease may be more common than what was previously held. There was a high incidence of extra pulmonary TB in our study, lymph node involvement being the most common. Physicians working in Saudi Arabia should be aware of the unusual presentation of the disease. The high prevalence of drug resistant MTB emphasizes the importance of performing culture and sensitivity tests for MTB in all new cases.

Background: Latent tuberculosis infection (LTBI) is caused by Mycobacterium tuberculosis (MTB) in a state of non-replicating persistence (NRP). Recent evidence suggests that some very specific adaptations to oxygen depletion occur so that MTB undergoes hypoxic NRP state. In this study the modified slowly stirred, limited Head Space Ratio (0.5HSR) method was used to investigate the physiological response of MTB to different oxygen tension levels. Materials and Methods: For setting up the various NRP stages, some susceptible and drug resistant clinically isolated strains of MTB were cultivated in Dubos Tween-Albumin medium via hypoxically, slow stirring 0.5 HSR methods. Additionally, the effects of isoniazid, rifampin, pyrazinamide, ciprofloxacin and metronidazole against MTB were examined during NRP-1 and NRP-2 stages. The α-crystalline protein was detected during NRP-1 stage of the MTB cultures via performance of the suitable procedures for pellet preparation, washing and cell disruption and SDS-PAGE(Sodium dodecyl sulfate-polyacrylamide gel electrophoresis) technique. Results: NRP-1 and NRP-2 stages of MTB were assessed. The first three of the four drugs mentioned above affected the MTB at actively replicating period and the rifampin effect was continued slightly during NRP-1 stage. Metronidazole affected the MTB at anaerobic NRP-2 stage. Alpha-crystalline protein was detected in NRP -1 stage but was not detected at aerated cultures. Conclusion: Induction of the α-crystalline protein during hypoxic shift-down of MTB metabolism, and its function as a chaperone, suggests a critical role for this protein in the ability of MTB to persist without replicating in the hostile regions of the host's tissues. Therefore, for an effective TB control program, it is critical to understand the mechanisms of factors induction associated with the hypoxic condition of tubercle bacilli and some strategies for the identification of new drug targets must be developed and the persistence states in human lesions should be prevented as well.

Background: The effects of vitamins on human immune system have been well studied. Vitamin A deficiency and its effects on immune system in pulmonary tuberculosis (TB) patients have been established. This study was carried out to evaluate vitamin A supplementary effect on immunologic profile of tuberculosis patients. Materials and Methods: In a double-blind clinical trial, thirty-five patients with confirmed pulmonary tuberculosis were included. The case group received vitamin A injection, 50000 lU, every 10 days for two months along with standard treatment of TB; the control group received only anti-TB drugs. Immunologic profiles including CD3+, CD4+, CD8+, CD4+/CD8+, CD19+, HLA-DR, CD16+56+, and plasma vitamin A as well as nutritional status were assessed in both groups primarily and two months after above-mentioned treatments. Data were analysed using SPSS software version 10. Results: The study showed that there were not significant differences in mean(± SD) of age, body weight, height, body mass index (BMI), fat thickness and vitamin A plasma level between the vit A-receiving and control groups. The mean of peripheral blood CD3+ showed significant increase in patient-control group [71.8 ±7.9 % lymphocytes (after supplementation) compared with 68.3 ±10.7% (before supplementation); p= 0.014.]. This was also true about CD4+ (p= 0.001). CD4+ to CD8+ ratio and the mean of CD19+ showed significant decrease in the patient control group and the vit A-receiving group, respectively (p= 0.002 and p= 0.04, respectively). In contrast, there was an increased significant difference for CD+16+56+ mean in the above-mentioned groups which was more prominent in the vit A- receiving group (p=0.038). The means of HLA-DR and CD8+ did not show significant differences in both groups before and after supplementation. Conclusion: It seems that vitamin A supplementary effects on the quality of lymphocytic markers are remarkable. However, further studies should be performed regarding immunologic response quality.

Background: Regarding the noisy environment of schools and teachers’ complaint of hearing loss, the present study was performed for the evaluation of occupational hearing loss in different elementary school teachers. Materials and methods: Between 1995 and 2000, a case- control prospective analytical study was performed in Tehran city on 2000 elementary school teachers (case group) and 2000 individuals that were not teachers (control group).Both groups had similar age and sex. The age range was 25-55 yrs. The case group was selected from 10 educational districts of Tehran (1, 2, 5, 6, 9, 10, 13, 14, 17 and 18). The cases had no history of contact with confirmed hearing loss inducing factors. The control group had the same confounding variables as the case group. Evaluations were carried out in both groups by interview, making questionnaires, physical exam, pure-tone and speech audiometries; the results were recorded. Results: This survey showed that hearing sensitivity of the case group was lower than that of the control group (P<0.001) to different frequencies in both ears in regard to age, occupational history and working in different grades of elementary schools (grades 1 to 5). However, no significant difference was detected regarding hearing loss among the teaching grades and increased occupational history had no influence on this issue. Hearing loss was more significant in high frequencies (4 and 8 kHz) and was more prevalent in the latter (p<0.001). Conclusion: Occupational noise exposure causes high-frequency sensorineural hearing loss. Thus, we recommend to measure intensity of noise in elementary schools and vocational technical schools in particular. In addition, hearing sensitivity level of students and teachers should be measured before the admission and employment, respectively. Annual regular audiometric examinations should also be performed for high-risk individuals and knowledge regarding complications of occupational noise exposure should be increased. As a conclusion, decreasing the number of students in each class, quiet classrooms, decreasing the hours of teaching and using hearing protection devices can prevent noise induced hearing loss. (Tanaffos 2005; 4(14): 61-69)

Pulmonary manifestations of ulcerative colitis have been well recognized, but incidence of bronchiectasis is rare, particularly in children. In this study, a 16-year old girl is presented with rectorrhagy and abdominal cramp, who developed pulmonary symptoms as productive cough and dyspnea after a short period of time. Arterial blood gas (ABG) analysis showed hypoxia and hypercapnea. Chest x- ray and high resolution computerized tomography (HRCT) demonstrated honey comb pattern and changes indicating bronchiectasis in lower segments of both lungs. Ulcerative colitis pattern was present in rectosigmoid biopsy. Open lung biopsy was performed to achieve definite diagnosis. Pathologic findings along with clinical and radiological presentations revealed a bronchiectatic pattern. The patient underwent treatment with bronchodilators, sulfasalazine and prednisolone; consequently, the symptoms were relieved.