Eigenspace Template Matching for Detection of Lacunar Infarcts on MR Images

Detection of lacunar infarcts is important because their presence indicates an increased risk of severe cerebral infarction. However, accurate identification is often hindered by the difficulty in distinguishing between lacunar infarcts and enlarged Virchow-Robin spaces. Therefore, we developed a computer-aided detection (CAD) scheme for the detection of lacunar infarcts. Although our previous CAD method indicated a sensitivity of 96.8 % with 0.71 false positives (FPs) per slice, further reduction of FPs remained an issue for the clinical application. Thus, the purpose of this study is to improve our CAD scheme by using template matching in the eigenspace. Conventional template matching is useful for the reduction of FPs, but it has the following two pitfalls: (1) It needs to maintain a large number of templates to improve the detection performance, and (2) calculation of the cross-correlation coefficient with these templates is time consuming. To solve these problems, we used template matching in the lower dimension space made by a principal component analysis. Our database comprised 1,143 T₁- and T₂-weighted images obtained from 132 patients. The proposed method was evaluated by using twofold cross-validation. By using this method, 34.1 % of FPs was eliminated compared with our previous method. The final performance indicated that the sensitivity of the detection of lacunar infarcts was 96.8 % with 0.47 FPs per slice. Therefore, the modified CAD scheme could improve FP rate without a significant reduction in the true positive rate.     

Xanthomatous meningioma: a case report with review of the literature

Xanthomatous meningioma is an extremely rare variant of meningioma that is characterized histopathologically by the presence of tumor cells with lipid-filled vacuolated cytoplasm. In this report, we describe the fifth documented case of xanthomatous meningioma and review its clinicopathological features. A 76-year-old Japanese male presented with dizziness. Magnetic resonance imaging demonstrated a well-circumscribed tumor in the left parasagittal to frontal region with attachment of the dura mater. Histopathological examination of the resected specimen revealed proliferation of polygonal to spindle cells with eosinophilic cytoplasm and bland round to oval nuclei. Whorl formation and psammomas were scattered, and mitotic figures were rarely seen. A peculiar finding was the presence of extensive xanthomatous change continuing to the above-mentioned typical meningothelial meningioma. These tumor cells had clear vacuolated cytoplasm and bland round to oval nuclei. Immunohistochemically, xanthomatous cells were positive for epithelial membrane antigen. Accordingly, an ultimate diagnosis of xanthomatous meningioma was made. Our clinicopathological analysis revealed that xanthomatous meningioma affects children to young persons or the elderly, and four of five cases were located in the supratentorial region. Although the detailed mechanism underlying the xanthomatous change has not been clarified, this change is thought to result from a metabolic abnormality of the neoplastic meningothelial cells. Further, xanthomatous change has also been reported in atypical and anaplastic meningiomas. Therefore, it is important to recognize that xanthomatous change can occur in meningiomas, and to avoid misidentifying these cells as macrophages.     

Ephrin-B2 controls PDGFRβ internalization and signaling

B-class ephrins, ligands for EphB receptor tyrosine kinases, are critical regulators of growth and patterning processes in many organs and species. In the endothelium of the developing vasculature, ephrin-B2 controls endothelial sprouting and proliferation, which has been linked to vascular endothelial growth factor (VEGF) receptor endocytosis and signaling. Ephrin-B2 also has essential roles in supporting mural cells (namely, pericytes and vascular smooth muscle cells [VSMCs]), but the underlying mechanism is not understood. Here, we show that ephrin-B2 controls platelet-derived growth factor receptor β (PDGFRβ) distribution in the VSMC plasma membrane, endocytosis, and signaling in a fashion that is highly distinct from its role in the endothelium. Absence of ephrin-B2 in cultured VSMCs led to the redistribution of PDGFRβ from caveolin-positive to clathrin-associated membrane fractions, enhanced PDGF-B-induced PDGFRβ internalization, and augmented downstream mitogen-activated protein (MAP) kinase and c-Jun N-terminal kinase (JNK) activation but impaired Tiam1–Rac1 signaling and proliferation. Accordingly, mutant mice lacking ephrin-B2 expression in vascular smooth muscle developed vessel wall defects and aortic aneurysms, which were associated with impaired Tiam1 expression and excessive activation of MAP kinase and JNK. Our results establish that ephrin-B2 is an important regulator of PDGFRβ endocytosis and thereby acts as a molecular switch controlling the downstream signaling activity of this receptor in mural cells.     

Characteristics of instrumental activities of daily living and everyday memory in elderly women--method for assessment of abilities in early dementia

AIM: To demonstrate the characteristics of the Instrumental Activities of Daily Living (IADL), assessed by the Assessment of Motor and Process Skills (AMPS), and everyday memory functions (memory necessary function for daily life) assessed by the Rivermead Behavioral Memory Test (RBMT) in elderly people with dementia. To compare the ability and the function between them and community-dwelling normal subjects. METHODS: We divided the RBMT result into three categories: prospective memory, retrospective memory, and prospective memory+retrospective memory. The study was performed in102 women (68-92 years old) with dementia who lived in a healthcare facility or three group homes (n=52) and cognitively normal subjects who lived in their own homes (n=50). RESULTS: There were no associations between AMPS motor and prospective memory, retrospective memory, and prospective memory+retrospective memory in both groups. There were associations between the AMPS process and retrospective memory in both groups, but no associations between the AMPS process and prospective memory in either groups and a scatter chart revealed some subjects with a prospective memory deficit even though they had a normal IADL performance ability level. From those results, we found that IADL performance ability and everyday memory were not simultaneously damaged. CONCLUSION: When assessing elderly people, it is necessary to assess both IADL performance and everyday memory, including prospective memory. According to these methods, mild cognitive impairment may be screened more accurately.     

Successful treatment with azathioprine for autoimmune thrombocytopenia developing after autologous peripheral blood stem cell transplantation

A 60-year-old man with acute promyelocytic leukemia in complete remission had minimal residual disease (MRD). After two courses of arsenic trioxide treatment, the MRD disappeared. In October 2005, he received an unmanipulated autologous peripheral blood stem cell transplantation (autoPBSCT). Hematologic recovery was prompt; however, after day 21 following the autoPBSCT, platelet counts decreased to below 10 x 10(9)/l. A bone marrow aspirate showed an increased number of immature megakaryocytes, and platelet-associated IgG was elevated to 48.5 ng/10(7) platelets. A diagnosis of autoimmune thrombocytopenia was made. The combination of oral prednisolone (40 mg/day) and bolus immunoglobulin infusion (400 mg/kg, for 5 consecutive days) was ineffective. He was given azathioprine (50 mg/day, orally), and 10 days after the initiation of the treatment, the platelet counts gradually increased and recovered to over 50 x 10(9)/l on day 168, and 100 x 10(9)/l on day 364. To the best of our knowledge, successful treatment of ITP following auto PBSCT with azathioprine has not been previously reported.     

Leptin resistance does not induce hyperphagia in the rat

Leptin has been thought to work as a mediator for body weight control by inhibiting food intake. Leptin, however, cannot prevent obesity induced by a high-fat diet (HFD) probably because of leptin resistance. We investigated daily feeding and weight gain when ordinary chow (OC) was changed to a HFD in male rats. Food intake, by weight, significantly increased the next day, but gradually decreased until at 20 days the HFD intake contained the same calories as consumed by the OC-fed control rats. The reduction in food intake occurred only during the night without change of preference for the HFD, even after leptin resistance had developed. Nonetheless, the HFD-fed rats gained more weight than the controls. From the present experiment, it is concluded that leptin resistance does not induce hyperphagia, and suggested that body weight is not regulated to be constant.     

The performance of the automated immune chemiluminescent system "IMMULITE 2000XPi for the measurement of serum soluble IL-2 receptor in clinical samples

The performance of a chemical luminescence test reagent "Immulyze IL-2R II" with an automated immune chemiluminescent system "IMMULITE 2000XPi" for the measurement of serum soluble IL-2 receptor in clinical samples was investigated. The satisfactory results were obtained for the reproducibility, precision, linearity, and sensitivity, and no interference with hemolysis, bilirubin, chyle or intrafat was observed. A significant correlation was found between the values of sIL-2R measured by the Cell-free N IL-2R and those obtained by the IMMULYZE IL-2R II. The measurements were stable regardless of the methods of sample preservation, or repeated freeze-thawing procedures. Elevated concentrations of sIL-2R over 1,000 U/mL were found in multiple types of collagen diseases or severe cases of allergic diseases, indicative that sIL-2R levels might correlate with the severity of autoimmune diseases. In patients with lymphoma, sIL-2R levels correlated with the lactate dehydrogenase (LD) activity. Among the lymphoma cases with sIL-2R levels over 1,000 U/mL, the majority (84%) had significantly higher levels of LD, and among them, 81% were at the clinical stage IV. We observed that sIL-2R levels increased from the early stages of lymphoma, while LD activities increased at the advanced stages. Our present findings suggest that sIL-2R is a promising marker for the diagnosis of autoimmune and allergic diseases, and also for the diagnosis and staging of lymphomas.     

Evaluation of seasonal changes in hemoglobin A1c in diabetic patients

In order to evaluate seasonal changes in hemoglobin A1c (HbA1c) values, we examined HbA1c values among 34,590 patients in 2010, and calculated the monthly average of HbA1c values through the year. HbA1c values were the highest in March and the lowest in October with a difference of 0.30%. The similar annual pattern was observed in HbA1c values from 2006 to 2009. Then we selected 453 diabetic patients whose treatment did not change through the year, and calculated average HbA1c values in four seasons each. There were also significant seasonal changes in diabetic patients, which were the highest in the spring and the lowest in the autumn, especially found in patients with insulin therapy. These effects may be caused by cold climate, decreased physical activity, over food intake and body weight gain in the winter. These seasonal changes in HbA1c should be concerned in the case of health service research, clinical trials and evaluation of the effects of medical treatment.     

Novel compound heterozygous mutations of the growth hormone-releasing hormone receptor gene in a case of isolated growth hormone deficiency

ObjectiveTo elucidate the pathogenesis of isolated growth hormone (GH) deficiency in a Japanese girl without consanguinity.DesignA 2-year-old girl of height 77.2 cm (? 3.0 SD for Japanese girls) was found to have an insulin-like growth factor (IGF)-1 level of 7 ng/mL and IGF binding protein-3 (IGFBP-3) level of 0.41 μg/mL. GH responded modestly to a series of pharmacological stimulants, increasing to 2.81 ng/mL with insulin-induced hypoglycemia, 3.78 ng/mL with arginine, and 3.93 with GH-releasing hormone (GHRH). Following direct sequencing of the GHRH receptor (GHRHR) gene, evaluation by the luciferase reporter assay, immunofluorescence study, and in vitro splicing assay with minigene constructs was conducted.ResultsNovel compound heterozygous GHRHR gene mutations were identified in the patient. A p.G136V substitution elicited no luciferase activity increment in response to GHRH stimulation, with normal membranous expression. Splicing assay demonstrated that the IVS2 + 3a > g mutation would lead to aberrant splicing.ConclusionsA case of isolated GH deficiency due to novel GHRHR gene mutations was identified.     

Wound dressing composed of hyaluronic acid and collagen containing EGF or bFGF: comparative culture study

We developed a novel wound dressing composed of a hyaluronic acid (HA) and collagen (Col) spongy sheet containing epidermal growth factor (EGF) or basic fibrolast growth factor (bFGF) by freeze-drying method (EGF-wound dressing or bFGF-wound dressing, respectively). A wound dressing without any growth factor was prepared as a control in a similar manner as above (C-wound dressing). Intermolecular cross-linkage between Col molecules was induced by UV irradiation. The release behavior of free HA from the wound dressing was investigated using a C-wound dressing. The weight of C-wound dressing after 1 day, 3, 5, and 7?days of incubation on top of a Col gel sheet at the air–water interface (wound surface model) was 55, 36, 30, and 19% of the original weight, respectively. Most free HA and a part of Col was released from the cross-linked Col network in the wound dressing during incubation, as the original Col content in the wound dressing was 33%. Next, fibroblast proliferation was assessed in conventional culture medium preconditioned by immersion of a piece of C-, EGF-, or bFGF-wound dressing, i.e. C-conditioned medium, EGF-conditioned medium, or bFGF-conditioned medium. Cell proliferation in C-conditioned medium increased to approximately the same level as that in conventional medium. Cell proliferation in EGF- and bFGF-conditioned medium was 1.9 times and 2.6 times greater than that in conventional medium after 7?days of cultivation, respectively. Finally, cytokine production of fibroblasts was assessed in a wound surface model using a fibroblast-incorporating Col gel sheet (cultured dermal substitute [CDS]). CDS was elevated to the air–medium interface, on which each wound dressing was placed and cultured for 7?days. Fibroblasts in CDS covered with EGF-wound dressing released 3.6 times more vascular endothelial growth factor (VEGF) and 4.6 times more hepatocyte growth factor (HGF) when compared with the C-wound dressing. Fibroblasts in CDS covered with bFGF-wound dressing released 10.2 times more VEGF and 6.3 times more HGF when compared with the C-wound dressing. This finding indicates that bFGF-wound dressing can facilitate more effectively the VEGF and FGF production compared with EGF-wound dressing.