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Background: Noninvasive quantification of liver fat by gradient echo (GRE) technique is an interesting issue in quantitative magnetic resonance imaging. In this study, the fat content in patients with nonalcoholic fatty liver disease (NAFLD) was quantified with GRE sequences with different T1 and T2* weighting. Methods: This prospective, cross-sectional study was performed on thirty NAFLD patients. Sixteen GRE sequences with different T1 weighting were performed with four echo times. In each sequence, repetition time (TR) or flip angle was changed and other parameters were fixed. Forty-eight fat indexes (FIs) from 16 sequences were calculated based on three methods. To determine the relationship between FIs and histological findings, Pearson's correlation coefficient was used at the level of 1% significance. Results: Mean FIs which obtained from Eq. 3 have the maximum values in comparison to other FIs. The maximum FI was 23.58%, which related to heavily T1 weighted sequence obtained with method 3. The minimum FI was -2.49%, which related to the minimal T1 weighted obtained with method 2. FIs increase with a flip angle, especially at low flip angles. Increase the TR parameter decrease the FIs gradually. Calculated FIs with methods 1 and 3 stronger correlated with histological findings relative to calculated FIs with method 2. Conclusion: For fat quantification, T1 relaxation effects probably more critical than T2*. Flip angle parameter could be a major factor causing the overestimation of liver fat content. Sequences with low flip angle are more suitable for fat quantification with methods 1 and 3. In fat quantification with GRE techniques, it is possible that the third and fourth echoes are unnecessary. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze mutations occurring in the rpoB gene of Mycobacterium tuberculosis (MTB) isolates from clinical samples of extrapulmonary tuberculosis (EPTB). Seventy formalin‐fixed, paraffin‐embedded samples and fresh tissue samples from confirmed EPTB cases were analyzed. Nested PCR based on the rpoB gene was performed on the extracted DNAs, combined with cloning and subsequent sequencing. Sixty‐seven (95.7%) samples were positive for nester PCR. Sequence analysis of the 81 bp region of the rpoB gene demonstrated mutations in 41 (61.2%) of 67 sequenced samples. Several point mutations including deletion mutations at codons 510, 512, 513 and 515, with 45% and 51% of the mutations in codons 512 and 513 respectively were seen, along with 26% replacement mutations at codons 509, 513, 514, 518, 520, 524 and 531. The most common alteration was Gln → His, at codon 513, presented in 30 (75.6%) isolates. This study demonstrated sequence alterations in codon 513 of the 81 bp region of the rpoB gene as the most common mutation occurred in 75.6% of molecularly confirmed rifampin‐resistant strains. In addition, simultaneous mutation at codons 512 and 513 was demonstrated in 34.3% of the isolates. [ABSTRACT FROM AUTHOR]

Present study was aimed to examine the diagnostic utility of PCR and nested PCR techniques for the detection of Mycobacterium tuberculosis (MTB) DNA in samples from patients with extra pulmonary tuberculosis (EPTB). In total 80 formalin-fixed, paraffin-embedded (FFPE) samples comprising 70 samples with definite diagnosis of EPTB and 10 samples from known non-EPTB on the basis of histopathology examination, were included in the study. PCR amplification targeting IS6110, rpoB gene and nested PCR targeting the rpoB gene were performed on the extracted DNAs from 80 FFPE samples. The strong positive samples were directly sequenced. For negative samples and those with weak band in nested-rpoB PCR, TA cloning was performed by cloning the products into the plasmid vector with subsequent sequencing. The 95% confidence intervals for the estimates of sensitivity and specificity were calculated for each method. Fourteen (20%), 34 (48.6%) and 60 (85.7%) of the 70 positive samples confirmed by histopathology, were positive by rpoB-PCR, IS6110-PCR and nested-rpoB PCR, respectively. By performing TA cloning on samples that yielded weak (no.=8) or negative results (no.=10) in the PCR methods, we were able to improve their quality for later sequencing. All samples with weak band and 7 out of 10 negative samples, showed strong positive results after cloning. So nested-rpoB PCR cloning revealed positivity in 67 out of 70 confirmed samples (95.7%). The sensitivity of these combination methods was calculated as 95.7% in comparison with histopathology examination. The confidence intervals for sensitivity of the PCR methods were calculated as 11.39-31.27% for rpoB-PCR, 36.44-60.83% for IS6110-PCR, 75.29-92.93% for nested-rpoB PCR and 87.98-99.11% for nested-rpoB PCR cloning. The 10 true EPTB negative samples by histopathology, were negative by all tested methods including cloning and were used to calculate the specificity of the applied methods. The confidence intervals for 100% specificity of each PCR method were calculated as 69.15-100%. Our results indicated that nested-rpoB PCR combined with TA cloning and sequencing is a preferred method for the detection of MTB DNA in EPTB samples with high sensitivity and specificity which confirm the histopathology results. [ABSTRACT FROM AUTHOR]

Chloroma or granulocytic sarcoma (GS) is a malignant neoplasm of myeloid lineage that occur in a variety of anatomic sites other than the bone marrow including soft tissue, bone, lymph node, nasal fossa, skin and sometime in the orbit. In the subconjunctiva it is rarely reported. A 4-year-old girl with a history of treated acute myelogenous leukemia was referred to Farabi Eye Hospital, Tehran, Iran for the evaluation of subconjunctival mass that was appeared since one month ago. Cell blood count (CBC) of the patient was normal except for Hb=7gm/dl. General physical examination was normal except for the signs of anemia. Histopathological evaluation of subconjunctival mass showed a malignant large round cell neoplasm. Immunohistochemical studies confirmed granulocytic sarcoma. When confronting a large cell or undifferentiated round cell neoplasm, the possibility of myeloid sarcoma should be investigated. Myeloperoxidase (MPO), cluster designation (CD) molecules such as CD34, CD45, CD15, CD68 and lysozyme positivity or Leder staining are useful in this regard. [ABSTRACT FROM AUTHOR]

1), colonoscopy showed no significant findings, but at terminal ileum intubation multiple hookworms were seen attached to the mucosa (Video 1). This case further emphasizes the importance of terminal ileum intubation and of lowering the threshold for obtaining tissue biopsy during colonoscopy. [Extracted from the article]

Myofibroma is a neoplasia of myofibroblasts that can be solitary or multiple and it is found most commonly in the head & neck region including scalp, forehead, parotid region and oral cavity. In the eyelid it is rarely reported. It has a benign course in the solitary form and fatal in its multiple form. A 4 month male infant referred to Farabi hospital -the referral center for eye diseases- with a 2 month history of a mass in his eyelid with gradual enlargement with no other complaints. The only abnormal physical finding was a 2.5 cm mass in the eyelid. This mass was excised and sent to the hospital pathology laboratory. When confronting a spindle cell lesion with a nodular or multinodular growth pattern which appears biphasic due to alteration of light and dark staining areas, the surgical pathologist should think to the possibility of myofibroma. Its pattern of growth and architecture rules out the other differential diagnoses like nodular fasciitis, fibrous histiocytoma, infantile fibromatosis, and peripheral primitive neuroectodermal tumor, mesenchymal chondrosarcoma, malignant hemangiopericytoma, juvenile fibrosarcoma and poorly differentiated synovial sarcoma. In difficult cases immunohistochemical staining is helpful that is Vimentin & Actin positivity & Desmin, CK, EMA & S100 negativity.