Differential expression of CD11b/CD18 (Mo1) and myeloperoxidase genes during myeloid differentiation

During the course of differentiation of early human myeloid cells toward monocytes and granulocytes, cell surface expression of the cell adhesion molecule, CD11b/CD18 (Mo1) increases dramatically and expression of myeloperoxidase (MPO), a bacteriocidal enzyme, decreases markedly. Using the inducible promyelocytic cell line HL-60 as a model, we studied the mRNA expression of these genes. Differentiation of these cells along both a monocytic and a granulocytic pathway demonstrated that the mRNA levels of the two subunits of CD11b/CD18 increased in a pattern temporally and quantitatively similar to the increase in cell surface expression of this heterodimer. In contrast, the expression of MPO mRNA decreased in a temporal and quantitative pattern similar to the known decrease in MPO protein during differentiation, suggesting that regulation of these myeloid-specific proteins may occur at the level of mRNA expression. These findings have important implications with regard to the nature of the block in differentiation in acute nonlymphocytic leukemia and the regulation of myeloid gene expression.     

Splenic lymphoma with villous lymphocytes involves B cells with extensively mutated Ig heavy chain variable region genes

Splenic lymphoma with villous lymphocytes (SLVL) is a recently defined subgroup of chronic B-cell lymphoproliferative diseases. The characteristic morphology of the tumor cells, together with phenotypic and cytogenetic findings, indicate that it is a distinct entity, but the nature of the cell or origin and its relationship to other low- grade lymphomas is unclear. For B-cell tumors, analysis of the variable region heavy chain (VH) genes used to encode the clonal Ig has shown marked differences between histologic categories, both in gene usage and extent of somatic mutation. An investigation of VH genes used in five typical cases of SLVL has shown somatic hypermutation from germline sequences in all cases, indicating that the cell of origin has been exposed to the hypermutation mechanism. However, no clonal heterogeneity was detectable, demonstrating that the tumor cell does not accumulate further mutations. These characteristics are similar to those found in mature postfollicular B cells, such as plasma cells. The distribution of mutations leading to replacement amino acids differed among the cases, with three of five cases showing clear evidence for antigen selection.     

Rapid expansion of another downstream aortic aneurysm with the elephant trunk

A 75-year-old man developed persistent dysphagia 2 months after successful total arch replacement with a long elephant trunk (ET) for a distal arch aneurysm. Enhanced computed tomography revealed not only complete thrombosis of the distal arch aneurysm, but also rapid expansion of another downstream aortic aneurysm with esophageal compression. Thoracic endovascular aortic repair was undertaken for this symptomatic aortic aneurysm, which was totally thrombo-excluded. ET might produce turbulent or jet-like blood flow from its tip in some situations and have a potential to accelerate the expansion of the downstream aneurysm. Additional endovascular ET completion is simple, effective, and less invasive.     

Developmental mechanisms of the tympanic membrane in mammals and non‐mammalian amniotes

The tympanic membrane is a thin layer that originates from the ectoderm, endoderm, and mesenchyme. Molecular‐genetic investigations have revealed that interaction between epithelial and mesenchymal cells in the pharyngeal arches is essential for development of the tympanic membrane. We have recently reported that developmental mechanisms underlying the tympanic membrane seem to be different between mouse and chicken, suggesting that the tympanic membrane evolved independently in mammals and non‐mammalian amniotes. In this review, we summarize previous studies of tympanic membrane formation in the mouse. We also discuss its formation in amniotes from an evolutionary point of view.     

Cutaneous Crohn''s disease mimicking Melkersson–Rosenthal syndrome: treatment with methotrexate

A woman with a 5-year history of unilateral orofacial granulomatosis required repeated evaluations (including sequential colonoscopies) to establish the diagnosis of cutaneous Crohn's disease, a condition that proved responsive to low doses of oral methotrexate administered weekly. To our knowledge this is the first report describing the use of methotrexate for treatment of orofacial granulomatosis caused by underlying Crohn's disease.     

Correlation of acetylcholinesterase activity in the brain and blood of wistar rats acutely infected with Trypanosoma congolense

ObjectiveTo investigate the neurotransmitter enzyme Acetylcholinesterase (AChE) activity in the brain and blood of rats infected with Trypanosoma congolense (T. congo).MethodsPresence and degree of parasitemia was determined daily for each rat by the rapid matching method. AChE activity was determined by preparing a reaction mixture of brain homogenate and whole blood with 5, 5-dithiobisnitrobenzioc acid (DTNB or Ellman's reagent) and Acetylthiocholine (ATC). The increase in absorbance was recorded at 436 nm over 10 min at 2 min intervals. Trypanosome species identification (before inoculation and on day 10 post infection) was done by Polymerase chain reaction using specific primers.ResultsThe AChE activity in the brain and blood decreased significantly as compared with the uninfected control. The AChE activity dropped to 0.32 from 2.20 μmol ACTC min^?1mg protein^?1 in the brain and 4.57 to 0.76 μmol ACTC min-1mg protein^?1 in the blood. The animals treated with Diminaveto at 3.5 mg/kg/d were observed to have recovered significantly from parasitemia and were able to regain AChE activity in the blood but not in the brain as compared to the control groups. We also observed, that progressive parasitemia resulted to alterations in PCV, Hb, RBC, WBC, neurophils, total protein, lymphocytes, monocytes and eosinophil in acute infections of T. congo. Polymerase chain reaction (PCR) of infected blood before inoculation and on day 10 post infection revealed 600 bp on agarose gel electrophoresis.ConclusionsThis finding suggest that decrease in AChE activity increases acetylcholine concentration in the synaptic cleft resulting to neurological failures in impulse transfer in T. congo infection rats.     

Colposuspension or TVT with anterior repair for urinary incontinence and prolapse: results of and lessons from a pilot randomised patient-preference study (CARPET 1)

In a multicentre randomised, unblinded patient preference pilot trial to assess the feasibility of a definitive randomised trial comparing colposuspension with tension-free vaginal tape (TVT) plus anterior repair in women with incontinence and prolapse, we found that 31 of 56 eligible women agreed to participate (55%). Recruitment was more successful face to face (87%) than by letter (16%). Only four of our women agreed to be randomised, 21 (68%) chose anterior repair + TVT and six (19%) chose colposuspension. This study demonstrates the importance of pilot work for complex trials to identify issues likely to adversely affect recruitment.     

Quantification of hepatic steatosis with MRI: The effects of accurate fat spectral modeling

Purpose

To develop a chemical‐shift–based imaging method for fat quantification that accounts for the complex spectrum of fat, and to compare this method with MR spectroscopy (MRS). Quantitative noninvasive biomarkers of hepatic steatosis are urgently needed for the diagnosis and management of nonalcoholic fatty liver disease (NAFLD).

Materials and Methods

Hepatic steatosis was measured with “fat‐fraction” images in 31 patients using a multiecho chemical‐shift–based water‐fat separation method at 1.5T. Fat‐fraction images were reconstructed using a conventional signal model that considers fat as a single peak at –210 Hz relative to water (“single peak” reconstruction). Fat‐fraction images were also reconstructed from the same source images using two methods that account for the complex spectrum of fat; precalibrated and self‐calibrated “multipeak” reconstruction. Single‐voxel MRS that was coregistered with imaging was performed for comparison.

Results

Imaging and MRS demonstrated excellent correlation with single peak reconstruction (r² = 0.91), precalibrated multipeak reconstruction (r² = 0.94), and self‐calibrated multipeak reconstruction (r² = 0.91). However, precalibrated multipeak reconstruction demonstrated the best agreement with MRS, with a slope statistically equivalent to 1 (0.96 ± 0.04; P = 0.4), compared to self‐calibrated multipeak reconstruction (0.83 ± 0.05, P = 0.001) and single‐peak reconstruction (0.67 ± 0.04, P < 0.001).

Conclusion

Accurate spectral modeling is necessary for accurate quantification of hepatic steatosis with MRI. J. Magn. Reson. Imaging 2009;29:1332–1339. © 2009 Wiley‐Liss, Inc.