فصلنامه علوم پزشکی دانشگاه آزاد اسلامی
سال بیست و یکم شماره 2 (پیاپی 64، تابستان 1390)

The Cell cycle of eukaryotes is an ordered set of events, culminating in cell growth and division into two daughter cells. Cell cycle consists of G1, S, G2 and M phases. M phase is divided to five sub-phases of prophase, prometaphase, metaphase, anaphase and telophase. At the end, two daughter cells are separated by cytokinesis. Cell cycle has checkpoints that ensure passage through different steps. Mutation or over- expression into genes coding checkpoint proteins can cause cancer. Regulation of mitosis process is controlled by post translation in some protein kinases. CyclinB/Cdk1 initiates and makes progress mitosis. Some kinases, like Aurora kinases, NIMA and PLK, have vital role in mitosis. Aurora kinases have important roles in cell cycle, such as mitotic spindle assembly and metaphase chromosome bi-orientation. Aberrant expression of Aurora kinases can disrupt checkpoints and cause genomic instability to promote tumor initiation. Aurora kinase come in focus when they known as “Bona fida oncogens”. Human genome has three Aurora kinases, including Aurora kinases A, B, and C. Proteins with selective functions in cell cycle, especially cell cycle dependent kinases, are known as new drug targets for cancer treatment. Several studies have shown association of aurora kinases and malignancy; so, they have been considered as a target for developing new drugs in the treatment of cancer. Increasing our knowledge about function and regulation of these magic kinases can lead us to develop drugs for cancer treatment

Due to wide range of application of L-Lysine, as an essential amino acid, in different industries, the demand for this amino acid has been increased and this has been led to the development of research on industrial production of L-Lysine.

In this study, we tried to increase the yield of production of L-Lysine by genetic optimization. After inspection of different effective enzymes in Lysine biosynthesis pathway, Diaminopimelate dehydrogenase (EC1.4.1.16) enzyme was selected. This enzyme would be coded by ddh gene. After chromosomal DNA extraction of C.glutamicum ATCC 21799 and designing of primers, the gene fragment was separated from genome by PCR with pfu DNA polymerase enzyme and was cloned in TAcloning vector for facilitation of cloning and determination of nucleotide sequence. Then, enzymatic digestion of TAcloning vector and pET28a vector were performed by EcoRI and SalI restriction enzymes which their products were ddh gene and linear vector. Ligation reaction was accomplished and for checking the accuracy of ligation, it was transformed into E.coliDH5α and finally in expression host, E.coli BL21(DE3).

The 1150bp band in PCR products and enzymatic digestion of extracted vectors with EcoRI and SalI, sequencing and SDS-PAGE confirmed the accuracy of cloning. Recombinant bacterial colonies were investigated and confirmed by two methods (PCR and enzymatic digestion).

This study showed significant increased expression rate of DAP dehydrogenase enzyme in this expression vector for the first time.

Streptococcus mutans, resident in the oral cavity, is able to produce bacteriocins with antimicrobial properties, called mutacins. Aim of this study was to investigate the antagonistic properties of these bacteria isolated from Iranian patients. Antibacterial activities of mutacins were evaluated against S. mutans ATCC 35668 with disc diffusion and genes encoding mutacin types I, II and III was determined by PCR amplification method. Of 32 S. mutans isolated from caries-active and caries-free individuals, 25 strains demonstrated antimicrobial repertoire and 67.2 % showed positive genotypes by PCR. This study showed that mutacins of Streptococcus mutans have antagonistic effects on the growth of other bacteria. Extract of this component could be used as antibacterial drug.

Peripheral blood fibrocytes are a newly identified circulating leukocyte subpopulation that migrates into injured tissue where it may display fibroblast-like properties and participate in wound healing and fibrosis of skin and other organs. In this study, fibrocyte recruitment to skin in a bleomycin-induced dermal fibrosis model of human scleroderma in vivo was studied. Sections of skin from normal mice) control group) and bleomycin-treated C57BL/6 mice (Experimental group) were stained for Procollagen α2 Type I and CD34 and the double stained cells, and also fibrocytes were counted in the tissue sections. There were more fibrocytes in the dermis of experimental group than control group. There was no significant difference in fibrocyte number between skin samples with 1 week bleomycin treated and 3 weeks treated samples. We also found that fibrocytes (CD34+ and procollagen+) were mainly localized in clusters around blood vessels in the dermis and also individually close to epithelium. Our data suggest an important role of fibrocytes in the pathology of dermal fibrosis.

Carpets are commonly used in our lives and are in contact with microorganisms. Antimicrobial agents should be used for the prevention of unwanted effects of microorganisms and control of their transmission. In this study, antimicrobial suspension of nano- silver was used for covering of nylon carpets. Different concentrations of nano- silver suspension were used by spraying method for covering of nylon carpets. In different examinations, small pieces of carpets (0.5 ´ 1 cm2) were treated with bacterial suspensions of Staphylococcus aureus and Escherichia coli. Before and after examination, the numbers of bacteria were counted and decreasing rate of them was determined. In nylon carpet with 25 ppm nano silver, decreasing rate of bacteria was 73.3%, while in carpets with 50 ppm and more, decreasing rate was 99.9%. Silver stability was assessed after 1 to 10 times of standard washing in 60 ºC with household bleach for 20 min. Silvers of carpet surface were established and saved their antibacterial effects after washing. Spraying nano- silver solution on commodities and factory products can prevent transmission of many microorganisms and infection diseases.

Accurate measurement of the exercise tolerance of cardiac patients prior to, and upon completion of a cardiac rehabilitation program using an objective measure is important. The aim of this study was to characterize the effects of an endurance and resistance exercise training program on physical capacity, blood pressure, heart rate and myocardial oxygen consumption in patients undergoing coronary artery bypass grafting. In this case- control study, 31 patients (21 men and 10 women, mean age 54.45±7.8) who were participating in the recovery phase II cardiac rehabilitation program and 15 patients (9 men and 6 women mean age 55.35±5.7) were assigned to the control group. Exercise program consisted of endurance and resistance exercise with duration of 60 min/session and frequency of 3 sessions/ week for 2 months and dietitian and psychiatric counseling. After rehabilitation, the case group demonstrated significant improvements in exercise test time, maximum systolic blood pressure, maximum heart rate and rate pressure product (p< 0.001). On the other hands, the case group demonstrated significant decreasing in rest heart rate, rest systolic blood pressure (p< 0.001). There were no changes in any variables for control group. Cardiac rehabilitation program is effective in promoting an early improvement in exercise capacity, RPP, HRR in patients undergoing CABG. Moreover, it induces significant decreasing in rest systolic and diastolic blood pressure.

Premenstrual syndrome (PMS) is a disorder with physical, psychological and behavioral changes frequently occurs in the luteal phase of women and causes frustration and dysfunction in daily relations with others. Therefore, this study was performed to evaluate the impact of group cognitive- behavioral instruction on decreasing headache, gobbler, tender breast, abdominal bloating and extremities edema. In this quasi- experimental study, in a definite region of Tehran, 56 mothers of preschool children who were suffering from this syndrome were selected by volunteer sampling and randomly divided to experimental (n=26) and control (n= 30) groups. Experimental group received 10 sessions of cognitive– behavioral instruction. Cognitive- behavioral instruction had a significant impact on physical symptoms, including headache, abdominal bloating and gobbler, but tender breast and extremities edema were not improved. Cognitive– behavioral instruction is an effective technique in the treatment of physical symptoms of the premenstrual syndrome. So, it is recommended, with or without drug therapy, among patients who don’t respond to medical therapy or refuse to take medication.

In medical field و prevention and treatment of articular diseases are very important. Regarding the effect of soya on the treatment of articular diseases, we decided to underline the preference of soya compared to complete protein regimen on the growth of articular cartilage.

30 female mice (Balb/C) with 3 weeks ages were divided to three groups. Each group was fed by three different regimens: The first one; enriched protein without soya, the second one; low protein regimen, and the third: enriched protein regimen with 40% soya. At the end of 6 months, the blood samples were collected from cardiac puncture under general anesthesia and the serum level of alkaline phosphatase was measured. Then, both hind limbs were removed and after histological preparing, the thickness of the middle part of tibia cartilage, the number of chondrocytes, the concentration of intercellular substance, and the thickness of the lateral part of tibial cartilage were measured using computer assisted histomorphometric analysis.

There was statistically significant increase in the thickness of the middle and lateral part of tibia cartilage, the number of chondrocytes and the serum level of alkaline phosphatase in the soya content regimen compared to the other groups (P<0. 001).

This study showed that soya can stimulate the production of alkaline phosphatase, increasing of the number of chondrocytes and thickness of cartilage, and also may have an effective role in the maintenance of cartilage.

Definite diagnosis of Candida pneumonia remains a problem in medicine. Although, isolation of Candida spp. from the bronchoalveolar lavage is not diagnostic by itself, it may be helpful in early diagnosis of pulmonary candidiasis in immunocompromised or critically ill patients and prompt antifungal therapy.

In a cross- sectional study, bronchoalveolar lavage was obtained from 144 patients with pulmonary diseases and different predisposing factors. All specimens were examined by direct microscopy and inoculated on CHOROM agar candida plates. Corn-meal agar medium and API 20C diagnostic kit also were used for identification of different stains of Candida.

Candida spp. was isolated from 74 (51.3%) specimens. The most common isolated species was Candida albicans with frequency of 69.7%, followed by C.glabrata (20.2%), C.kefyr (5.6%), C.krusei (2.25) and C.tropicalis (1.2%). Hypercolonization (≥103 CFU/mL) was found in 10 patients.

This report implies the high frequency (30.3%) of non- albicans Candida spp. isolated from respiratory tract, necessity the application of other diagnostic methods and following up the patients. Less susceptibility of non- albicans Candida spp. to present anti- fungal drugs must be noted and hypercolonization of respiratory tract with Candida spp. should be considered as a initiating factor for invasive candidiasis.

Mastery in critical thinking skills is the ultimate goal of learning in medical education. This study was conducted to determine and compare critical thinking skills of first- and last-term baccalaureate students of nursing, midwifery and occupational therapy among medical Universities of Tehran city in 2006. This descriptive- comparative study was performed on 426 freshman and senior students of three medical Universities of Tehran city, including Shaheed Beheshti, Tehran and Iran. The students were completed a demographic form and California Critical Thinking Skills Test (Form B). There was a significant difference between total critical thinking scores of the first- and last-term students of nursing and midwifery in Shaheed Beheshti and Iran Universities ((p<0.04 and P<0/03, respectively), while there was no significant difference in other groups. In addition, no significant difference was found in total critical thinking scores of students at different disciplines and Universities. This study showed no significant increase in critical thinking skills of senior students. This may be due to lack of pay attention to education of critical thinking skills in Universities.

Brucellosis is one of the most common joint diseases of humans and livestock, which has a high prevalence levels. Diversity of clinical symptoms and sometimes unusual symptoms of the disease confuses physicians regarding the diagnosis and treatment. This increases duration of disease, treatment costs and also mortality and morbidity. Case Report: A47-year-old man with rural agricultural job admitted to emergency room of Imam Hossein hospital of Shahroud, complaining prolonged fever, weakness, paralysis, nausea, anorexia and abdominal pain, and jaundice. Initial laboratory exams, including Wright, coomb’s Wright and 2ME, were normal except increased value of BUN and creatinine. Ultrasound and CT scan of abdomen were normal. After 3 days, repetition of tests showed positive Wright and 2ME. Standard treatment with anti- brucellosis drugs was prescribed. After ten days, he discharged from the hospital and treatment continued at home. Awareness of different manifestations of brucellosis leads to early diagnosis and treatment and also prevention of complications.

Splenic involvement and multiple abscess formation in tuberculosis disease (TB) are rare. The fact that the most common cause of splenic abscess formation is infection, this complication should always be in the differential diagnosis, especially in patients with febrile diseases and immune deficiency and or intravenous drug abuser. Tuberculosis splenic abscess may be the first and only sign of tuberculosis. Case Report: A 30- year old addicted and HIV positive man admitted to Bu-Ali hospital of Tehran with symptoms of fever, chills, fatigue, weight loss since 2 months ago, characteristic sepsis, jaundice and very bad general condition. Ultra-sonography and CT scan showed some masses (abscess) in the liver, spleen, pancreas and some Para-aortic lymph nodes. Patient underwent laparotomy because of abdominal pain, tenderness and rebound tenderness. Abundant small abscesses were seen in the spleen during operation and then splenectomy was done. The patient passed away next day after operation. Pathologic study revealed multiple abscesses in the spleen containing numerous positive acid-fast bacilli. In patients with fever and other symptoms of infectious diseases, especially persisting symptoms, underlying conditions, immune deficiency and malignancy should be considered. Advent of AIDS has again increased the frequency of tuberculosis. Therefore, Clinicians should bear in mind tubeculosis in those who are addicted and HIV positive. TB may be presented by abdominal abscesses in abdominal viscera in immunocompromised patients.