t(X;14)(p11.4;q32.33) is recurrent in marginal zone lymphoma and up-regulates GPR34

Genetic events underlying pathogenesis of nodal and extranodal marginal zone lymphoma are not completely understood. We report here a novel t(X;14)(p11.4;q32.33) identified in 4 lymphoma cases: 2 with a mucosa-associated lymphoid tissue lymphoma, one with a nodal marginal zone lymphoma and one with gastric diffuse large B-cell lymphoma. In all cases, lymphoma evolved from a previous auto-immune disorder. Fluorescence in situ hybridization and molecular studies showed that t(X;14), which is mediated by immunoglobulin heavy chain locus, targets the GPR34 gene at Xp11.4. Upregulation of GPR34 mRNA and aberrant expression of GPR34 protein has been demonstrated in 3 presented cases by quantitative real-time polymerase chain reaction and immunohistochemistry, respectively. GPR34 belongs to the largest family of cell surface molecules involved in signal transmission that play important roles in many physiological and pathological processes, including tumorigenesis. Although functional consequences of t(X;14) have not been identified, our studies suggest that up-regulated GPR34 activate neither nuclear factor-κB nor ELK-related tyrosine kinase.     

The Mandibular Ridge Oral Mucosa Model of Stromal Influences on the Endothelial Tip Cells: An Immunohistochemical and TEM Study

This study aimed to evaluate by immunohistochemistry and transmission electron microscopy (TEM) the morphological features of the oral mucosa endothelial tip cells (ETCs) and to determine the immune and ultrastructural patterns of the stromal nonimmune cells which could influence healing processes. Immune labeling was performed on bioptic samples obtained from six edentulous patients undergoing surgery for dental implants placement; three normal samples were collected from patients prior to the extraction of the third mandibular molar. The antibodies were tested for CD34, CD117(c‐kit), platelet derived growth factor receptor‐alpha (PDGFR‐α), Mast Cell Tryptase, CD44, vimentin, CD45, CD105, alpha‐smooth muscle actin, FGF2, Ki67. In light microscopy, while stromal cells (StrCs) of the reparatory and normal oral mucosa, with a fibroblastic appearance, were found positive for a CD34/CD44/CD45/CD105/PDGFR‐α/vimentin immune phenotype, the CD117/c‐kit labeling led to a positive stromal reaction only in the reparatory mucosa. In TEM, non‐immune StrCs presenting particular ultrastructural features were identified as circulating fibrocytes (CFCs). Within the lamina propria CFCs were in close contact with ETCs. Long processes of the ETCs were moniliform, and hook‐like collaterals were arising from the dilated segments, suggestive for a different stage migration. Maintenance and healing of oral mucosa are so supported by extensive processes of angiogenesis, guided by ETCs that, in turn, are influenced by the CFCs that populate the stromal compartment both in normal and reparatory states. Therefore, CFCs could be targeted by specific therapies, with pro‐ or anti‐angiogenic purposes. Anat Rec, 2013. © 2012 Wiley Periodicals, Inc.     

Common genetic coagulation variants are not associated with ischemic stroke in a case-control study

Abstract

Objective: Abnormalities in the coagulation pathway are often included in the diagnostic work-up of stroke patients, especially in young adults with cryptogenic stroke.

Methods: Three common genetic variants within the coagulation cascade were investigated in 500 control subjects and in 167 patients with ischemic stroke defined by TOAST subclassification. Analysed variants were factor V Leiden, prothrombin 20210G→A and factor XIII Val34Leu.

Results: The factor V Leiden mutation was over-represented in patients with cardioembolic stroke for trend, whereas the prothrombin 20210G→A variant and the factor XIII polymorphism Val34Leu were not associated with stroke of any subtype. The three polymorphisms showed no association with stroke in subgroups of patients defined by age (<40, 40–49, 50–59, ≥60 years).

Discussion: This study suggests that the analysis of prothrombin 20210G→A and factor XIII Val34Leu is not a useful diagnostic procedure in the work-up of ischemic stroke.     

血小板第4因子抑制巨核细胞系膜结合型c-kit的表达(英文)

细胞表面受体c-kit与干细胞因子(SCF)对维持血细胞的生成起重要作用。血小板第4因子(PF4)能特异性地抑制巨核细胞生成。在本实验中研究了PF4对两个巨核细胞系HEL和Dami的c-kit表达影响。结果显示,经PF4处理的两株细胞,其c-kit mRNA表达量均下降,细胞表面受体数量降低,SCF与c-kit的结合量亦下降,两组差异有显著意义。在对细胞膜CD34表达影响方面,PF4与TGFβ1的作用相反,PF4促进CD34的表达,而TGFβ1抑制CD34的表达。研究表明,PF4抑制巨核细胞生长的机理,部分途径可能是通过抑制c-kit/SCF而产生。     

Antimicrobial susceptibility surveillance of obligate anaerobic bacteria in the Kinki area

Obligate anaerobes exist as resident flora in various sites in humans, but they are also emphasized as endogenous causative microorganism of infections. We performed surveillance to understand the trend of drug susceptibility in obligate anaerobic bacteria in the Kinki area of Japan. In the experiment, we used 156 obligate anaerobe isolates collected from 13 institutions that participated in the Study of Bacterial Resistance Kinki Region of Japan. MALDI Biotyper was used to identify the collected strains, and among the 156 test strains, those that could be identified with an accuracy of Score Value 2.0 or more included 6 genera, 30 species, and 144 strains (Bacteroides spp. 77 strains, Parabacteroides sp. 2 strains, Prevotella spp. 29 strains, Fusobacterium spp. 14 strains, Porphyromonas spp. 2 strains, and Clostridioides difficile 20 strains), and they were assigned as subject strains for drug susceptibility testing. The drug susceptibility test was carried out by broth microdilution method using Kyokuto Opt Panel MP ANA (Kyokuto Pharmaceutical Industrial Co., Ltd., Tokyo, Japan) and judged according to CLSI criteria. As a result, Bacteroides and Parabacteroides species showed good sensitivities to tazobactam-piperacillin, imipenem, metronidazole and chloramphenicol, and low sensitivities to ampicillin, cefoperazone and vancomycin. Prevotella species showed good sensitivities to sulbactam-ampicillin, tazobactam-piperacillin, cefmetazole, imipenem, doripenem and metronidazole. Susceptibility rates to other drugs were slightly different depending on the bacterial species. Both Fusobacterium spp. and Porphyromonas spp. showed high sensitivities to many drugs. C. difficile was highly sensitive to vancomycin and metronidazole, having MIC₉₀s of 0.5 μg/mL and ≤2 μg/mL, respectively.