141 research outputs found
General qualitative survey on learning strategies employed by deaf EFL learners
This paper, through using relevant literature, covers issues which are effective in planning a strategy by deaf EFL learners who are using learning strategies like cognitive, meta-cognitive and socio-affective strategies
Computerised tomography scan in multi-drug-resistant versus extensively drug-resistant tuberculosis
Purpose: Multi-drug-resistant tuberculosis (MDR-TB) is simultaneously resistant to isoniazid and rifampin. Of course, this germ may also be resistant to other anti-tuberculosis drugs. Patients with extensively drug-resistant tuberculosis (XDR-TB) are also resistant to all types of fluoroquinolone and at least one of the three injectable medications: amikacin, clarithromycin, or kanamycin, in addition to isoniazid and rifampin. Therefore, the main objective of the current study was to evaluate and compare the computed tomography (CT) scan findings of MDR-TB and XDR-TB patients. Material and methods: In this comparative descriptive cross-sectional study 45 consecutive TB patients who referred to Masih Daneshvari Hospital, Tehran, Iran from 2013 to 2019 were enrolled. TB was diagnosed based on sputum smear and sensitive molecular and microbial tests. Patients were divided into two groups (MDR-TB and XDR-TB) based on two types of drug resistance. CT scan findings were compared for cavitary, parenchymal, and non-parenchymal disorders. The early diagnostic values of these factors were also calculated. Results: Findings related to cavitary lesions including the pattern, number, size of the largest cavity, maximum thickness of the cavity, lung involvement, number of lobes involved, and the air-fluid levels in the two patient groups were similar (p > 0.05). Parenchymal findings of the lung also included fewer and more nodules of 10 mm in the MDR-TB and XDR-TB groups, respectively. Tree-in-bud, ground-glass-opacity, bronchiectasis, cicatricial emphysema, and lobar atelectasis were similar in the two patient groups (p > 0.05). Findings outside the parenchymal lung, including mediastinal lymphadenopathy and pericardial effusion, showed no statistically significant difference between the MDR-TB and XDR-TB groups (p > 0.05). Parenchymal calcification was more common in the XDR group than in the MDR group (64.7% and 28.6%, respectively) with a significant difference (p = 0.01). Conclusions: CT scan findings in patients with XDR-TB are similar to those of patients with MDR-TB for cavitary, parenchymal, and non-parenchymal lung characteristics. However, patients with XDR-TB tend to have more parenchymal calcification and left-sided plural effusion. CT characteristics overlap between XDR-TB and those with MDR-TB. It can be concluded that CT scan features are not sensitive to the diagnosis
An Overview of The Available Methods for Morphological Scoring of Pre-Implantation Embryos in In Vitro Fertilization
Assessment of embryo quality in order to choose the embryos that most likely result in
pregnancy is the critical goal in assisted reproductive technologies (ART). The current
trend in human
in vitro
fertilization/embryo transfer (IVF/ET) protocols is to decrease the
rate of multiple pregnancies after multiple embryo transfer with maintaining the pregnancy
rate at admissible levels (according to laboratory standards). Assessment of morphological feathers as a reliable non-invasive method that provides valuable information in prediction of IVF/intra cytoplasmic sperm injection (ICSI) outcome has been frequently proposed
in recent years. This article describes the current status of morphological embryo evaluation at different pre-implantation stages
Polymorphism and synergism of angiotensin-converting enzyme (ACE) and plasminogen activator inhibitor-1 (PAI-1) genes in coronary artery disease
Introduction: Among the genetic factors for coronary artery diseases, PAI-1 4G/5G and ACE I/D polymorphisms can be noted. This study was carried out to investigate the association of these two polymorphisms and their synergism in coronary artery disease (CAD) from a sample of the Iranian population. Materials and methods: Sixty-one patients with a history of CAD and 92 healthy controls participated in our study. After DNA extraction from leukocytes, PCR was performed to characterize PAI-1 4G/5G and ACE I/D polymorphisms, using an amplification refractory mutation system technique. Results: In the studied patients, PAI-1 polymorphisms were 24.6, 45.9, and 29.5 for 4G/4G, 4G/5G and 5G/5G, respectively; the values for controls were 20.7, 42.2 and 37.0. The distribution rates of genotypes I/I, I/D and D/D in patients accounted for 29.5, 45.9 and 24.6; in the control group these figures were estimated to be 40.2, 40.2 and 19.6. Conclusion: Single and multivariate analyses showed a significant difference for the conventional risk factors, including hypertension, diabetes, hyperlipidemia, smoking and family history, for CAD between patients and controls (p value 0.001). However, no significant correlation was demonstrated considering ACE and PAI-1 polymorphisms either in association with 4G/4G or D/D genotypes or a combination of them in the Iranian population in the current study. © 2015 The Author(s)
The impact of N-myc amplification on median survival in children with neuroblastoma
Background: Neuroblastoma is the most common extracranial malignant solid tumor
in children under 5 years, and it is characterized by wide clinical and biological heterogeneity.
N-myc oncogene amplification is considered to be one of the most important
prognostic factors used to evaluate survival in these patients.
Objectives: The aim of our study was to determine amplification of the N-myc oncogene
using real-time quantitative polymerase chain reaction (PCR) and to show the influence
of N-myc amplified tumors on the overall survival rate.
Patients and Methods: This study is an analytical historical cohort study of forty children
with neuroblastoma admitted to the Shafa Hospital, Iran from 1999 to 2010. Paraffined
blocks of tumoral tissue were analyzed for N-myc amplification by a PCR. The
degree of N-myc amplification was derived from the ratio of the N-myc oncogene and
the single copy reference gene, NAGK. In the statistical analysis, a Kaplan-Meier survival
analysis was used.
Results: We found a variable degree of N-myc amplification, from 3 to 2 200, in 32 of
the 40 neuroblastomas (80%). NMYC amplification was seen more frequently in patients
older than 2.5 years (71.9%), stage 4 (65.6%) and female (53.1%). Median survival time in the
males was significantly longer than in the females (P = 0.03). The overall median survival
for N-myc amplified tumor patients was 20 months, and 30 months for the non amplified
tumors.
Conclusions: The N-myc amplified tumors may increase the probability of more aggressive
behavior and rapid tumor progression, especially in advanced stages of neuroblastoma.
This study confirmed the importance of obtaining correct measurements of oncogene
amplification in the early evaluation of neuroblastomas in order to target more
aggressive therapies in patients with a higher risk of cancer progression
Binding of the Bacillus subtilis LexA protein to the SOS operator
The Bacillus subtilis LexA protein represses the SOS response to DNA damage by binding as a dimer to the consensus operator sequence 5′-CGAACN(4)GTTCG-3′. To characterize the requirements for LexA binding to SOS operators, we determined the operator bases needed for site-specific binding as well as the LexA amino acids required for operator recognition. Using mobility shift assays to determine equilibrium constants for B.subtilis LexA binding to recA operator mutants, we found that several single base substitutions within the 14 bp recA operator sequence destabilized binding enough to abolish site-specific binding. Our results show that the AT base pairs at the third and fourth positions from the 5′ end of a 7 bp half-site are essential and that the preferred binding site for a LexA dimer is 5′-CGAACATATGTTCG-3′. Binding studies with LexA mutants, in which the solvent accessible amino acid residues in the putative DNA binding domain were mutated, indicate that Arg-49 and His-46 are essential for binding and that Lys-53 and Ala-48 are also involved in operator recognition. Guided by our mutational analyses as well as hydroxyl radical footprinting studies of the dinC and recA operators we docked a computer model of B.subtilis LexA on the preferred operator sequence in silico. Our model suggests that binding by a LexA dimer involves bending of the DNA helix within the internal 4 bp of the operator
Detection of human metapneumovirus and respiratory syncytial virus by real-time polymerase chain reaction among hospitalized young children in Iran
Background: Acute respiratory infection plays an important role in hospitalization of children in developing countries; detection of viral causes in such infections is very important. The respiratory syncytial virus (RSV) is the most common etiological agent of viral lower respiratory tract infection in children, and human metapneumovirus (hMPV) is associated with both upper and lower respiratory tract infections among infants and children. Objectives: This study evaluated the frequency and seasonal prevalence of hMPV and RSV in hospitalized children under the age of five, who were admitted to Aliasghar children�s hospital of Iran University of Medical Sciences from March 2010 until March 2013. Patients and Methods: Nasopharyngeal or throat swabs from 158 hospitalized children with fever and respiratory distress were evaluated for RSV and hMPV RNA by the real-time polymerase chain reaction (PCR) method. Results: Among the 158 children evaluated in this study, 49 individuals (31.1) had RSV infection while nine individuals (5.7) had hMPV infection. Five (55.5) of the hMPV-infected children were male while four (44.5) were female and 27 (55.2) of the RSV-infected patients were females and 22 (44.8) were males. The RSV infections were detected in mainly one year old children. Both RSV and hMPV infections had occurred mainly during winter and spring seasons. Conclusions: Respiratory syncytial virus was the major cause of acute respiratory infection in children under one-year of age while human metapneumovirus had a low prevalence in this group. The seasonal occurrence of both viruses was the same. © 2016, Ahvaz Jundishapur University of Medical Sciences
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