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31.
López-Giral S Quintana NE Cabrerizo M Alfonso-Pérez M Sala-Valdés M De Soria VG Fernández-Rañada JM Fernández-Ruiz E Muñoz C 《Journal of leukocyte biology》2004,76(2):462-471
B cell neoplasms present heterogeneous patterns of lymphoid organ involvement, which may be a result of the differential expression of chemokine receptors. We found that chemokine receptor (CCR)7, CXC chemokine receptor (CXCR)4, or CXCR5, the main chemokine receptors that mediate B cell entry into secondary lymphoid tissues and their homing to T cell and B cell zones therein, were highly expressed in B malignancies with widespread involvement of lymph nodes. Conversely, those pathologies with little or no nodular dissemination showed no expression to very low levels of CCR7 and CXCR5 and low to moderate levels of CXCR4. These findings provide evidence for the role of CCR7, CXCR4, and CXCR5 in determining the pattern of lymphoid organ involvement of B tumors. Functional studies were performed on B malignancies expressing different levels of CCR7, CXCR5, and CXCR4. Multiple myeloma (MM) cells did not express CCR7 nor CXCR5 and did not migrate in response to their ligands; a moderate expression of CXCR4 on MM cells was accompanied by a migratory response to its ligand, CXCL12. By contrast, cells from B cell chronic lymphocytic leukemia (B-CLL) expressed the highest levels of these chemokine receptors and efficiently migrated in response to all ligands of CCR7, CXCR4, and CXCR5. In addition, the migration index of B-CLL cells in response to both of the CCR7 ligands correlated with the presence of clinical lymphadenopathy, thus indicating that the high expression of functional chemokine receptors justifies the widespread character of B-CLL, representing a clinical target for the control of tumor cell dissemination. 相似文献
32.
Zamora-Perez A Zúñiga-González GM Gómez-Meda BC Ramos-Ibarra ML Batista-González CM Torres-Bugarín O 《Environmental and molecular mutagenesis》2004,44(5):436-440
The micronucleus (MN) assay can be used to detect the genotoxic effects of chemical agents in virtually any cell that divides frequently. Salamanders (Ambystoma sp.) are amphibians that can be easily maintained and bred in the laboratory and spontaneously shed their skin every 2.5-4 days. In this present study, we have evaluated the usefulness of this shed skin for the MN assay. We exposed salamanders to different concentrations of both the aneugen colchicine (COL) and the clastogen cyclophosphamide (CP) and we determined the frequency of micronucleated cells (MNCs) in their sheds. Fragments of shed skin were placed on clean slides, fixed, stained, observed with a light microscope, and the number of MNCs was counted. The MNC frequency was increased significantly by all doses of COL and CP tested, administered either as single or repeated exposures. The presence of MNCs in the shed skin and the speed of sloughing lead us to propose that the sheds of Ambystoma sp., or other amphibians that slough their skin, are suitable alternative models for detecting genotoxic exposures relevant to aquatic environments. 相似文献
33.
Ko AC Choo-Smith LP Hewko M Leonardi L Sowa MG Dong CC Williams P Cleghorn B 《Journal of biomedical optics》2005,10(3):031118
Early dental caries detection will facilitate implementation of nonsurgical methods for arresting caries progression and promoting tooth remineralization. We present a method that combines optical coherence tomography (OCT) and Raman spectroscopy to provide morphological information and biochemical specificity for detecting and characterizing incipient carious lesions found in extracted human teeth. OCT imaging of tooth samples demonstrated increased light backscattering intensity at sites of carious lesions as compared to the sound enamel. The observed lesion depth on an OCT image was approximately 290 microm matching those previously documented for incipient caries. Using Raman microspectroscopy and fiber-optic-based Raman spectroscopy to characterize the caries further, spectral changes were observed in PO4 (3-) vibrations arising from hydroxyapatite of mineralized tooth tissue. Examination of various ratios of PO4 (3-) nu2, nu3, nu4 vibrations against the nu1 vibration showed consistent increases in carious lesions compared to sound enamel. The changes were attributed to demineralization-induced alterations of enamel crystallite morphology and/or orientation. OCT imaging is useful for screening carious sites and determining lesion depth, with Raman spectroscopy providing biochemical confirmation of caries. The combination has potential for development into a new fiber-optic diagnostic tool enabling dentists to identify early caries lesions with greater sensitivity and specificity. 相似文献
34.
Chiara Fenoglio Daniela Galimberti Laura Piccio Diego Scalabrini Paola Panina Cecilia Buonsanti Eliana Venturelli Carlo Lovati Gianluigi Forloni Claudio Mariani Nereo Bresolin Elio Scarpini 《Neuroscience letters》2007
Triggering Receptor Expressed on Myeloid cells (TREM)2 deficiency originates a genetic syndrome characterized by bone cysts and presenile dementia, named Nasu-Hakola disease (NHD). Early onset dementia and marked involvement of frontal regions are features characterizing both NHD and other kinds of neurodegenerative disorders, such as Frontotemporal Lobar Degeneration (FTLD), and, in some cases, Alzheimer's disease (AD). Three Single Nucleotide Polymorphisms (SNPs) in TREM2 coding region were screened by allelic discrimination in a population of probable AD patients as well as FTLD patients as compared with age-matched controls. In addition, mutation scanning of the coding region of TREM2 gene was carried out in 7 patients with early onset AD (EOAD), 16 FTLD, and 20 controls. None of the SNPs analyzed was present, either in patients or controls. Moreover, mutation scanning of the five exons of TREM2 failed to detect the presence of novel polymorphisms. These data demonstrate that TREM2 coding region is highly conserved, implying a crucial role of this receptor. Further studies, including a functional analysis, are certainly required to clarify the role of TREM2 in neurodegenerative processes. 相似文献
35.
36.
Central precocious puberty and abnormal chromosomal patterns 总被引:1,自引:0,他引:1
Central precocious puberty (PP) can be caused by chromosomal aberrations. We report three patients presenting with central
PP in whom karyotype analysis demonstrated abnormal chromosomal patterns. The first patient was affected by the triple-X syndrome,
commonly characterized by premature ovarian failure. The second patient, a girl with inv dup(15)(pter→q12::q12→pter), had
a chromosomal aberration involving an imprinted region of the human genome, whose deletion is commonly associated with Prader-Willi
syndrome (PWS) and hypogonadotrophic hypogonadism. The third patient was a boy carrying a rare chromosome abnormality, the
duplication of chromosome 9 (q22→qter). All patients had mental retardation, which was mild in patient 1, moderate in patient
2, and severe in case 3. They underwent treatment with luteinizing hormone releasing hormone (LHRH) analogs, which were able
to stop the progression of the sexual development. We confirm that chromosomal aberrations are an important cause of central
PP, and that karyotype analysis in patients with PP and mental retardation, even if mild, is necessary because chromosomal
abnormalities can be present. 相似文献
37.
Iréne?LundEmail author Thomas?Lundeberg Louise?Sandberg Cecilia?Norrbrink?Budh Jan?Kowalski Elisabeth?Svensson 《BMC medical research methodology》2005,5(1):31
Background:
Rating scales like the visual analogue scale, VAS, and the verbal rating scale, VRS, are often used for pain assessments both in clinical work and in research, despite the lack of a gold standard. Interchangeability of recorded pain intensity captured in the two scales has been discussed earlier, but not in conjunction with taking the influence of pain etiology into consideration. 相似文献38.
Paola Origone Carlo Bellini Debora Sambarino Barbara Banelli Guido Morcaldi Carmen La Rosa Franco Stanzial Claudio Castellan Domenico A. Coviello Cecilia Garrè Eugenio Bonioli 《Human mutation》2003,22(4):341-341
In the original version of this article, the title was incorrect. Please find the correct title given here. The publisher deeply regrets this error. The original article to which this Erratum refers was published in Human Mutation 22:179–180 Human Mutation(2003) 22(2) 179–180 相似文献
39.
40.
The Yin-Yang of tumor-associated macrophages in neoplastic progression and immune surveillance 总被引:5,自引:1,他引:5
Paola Allavena Antonio Sica Cecilia Garlanda Alberto Mantovani 《Immunological reviews》2008,222(1):155-161
Summary: An intrinsic (oncogene-driven) pathway and an extrinsic (microenvironment-driven) pathway connect inflammatory reactions and cancer. M2-polarized tumor-associated macrophages and the related myeloid-derived suppressor cells are key prototypic components of smoldering inflammation driving neoplastic progression. However, mononuclear phagocytes can exert anti-tumor activity by killing tumor cells and eliciting tissue disruptive reactions (M1), a likely scenario in the early phases of carcinogenesis of immunogenic tumors and following therapeutic intervention. Shifting the macrophage balance represents a viable therapeutic target. Herein, the 'macrophage balance' is discussed in the context of the apparent paradox of tumor promotion by innate immunity-driven inflammation and the seemingly opposed tumor surveillance by adaptive immune responses. 相似文献