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1.
Background:  Nucleolin is a major nucleolar argyrophilic protein involved in carcinogenesis. There are only few studies on its tissue expression in human cancer and none in melanoma. We aimed at exploring this protein and its prognostic impact in cutaneous melanocytic lesions.
Methods:  We studied 193 cases including benign, dysplastic and malignant melanocytic lesions. Nuclear positivity was evaluated by immunohistochemistry and quantified by automated image analysis.
Results:  Most dysplastic and malignant lesions showed high percentages of cells with abnormal patterns of nuclear positivity (Abn+N) consisting in multiple, irregular, positive dots (ID+) and a coarse, irregularly positive nucleoplasm (CNpl+) or both (ID+CNpl+). The patterns CNpl+ and/or ID+CNpl+ were never observed in benign lesions, in which ID+ were also virtually absent. Abn+N% was significantly lower in dysplastic nevi than in primary melanomas and metastases and in primary melanomas than in metastases (p < 0.05). Furthermore, Abn+N was the second powerful prognostic discriminator, after melanoma thickness, and a significantly lower survival was observed in vertical growth phase melanoma patients showing Abn+N in more than 50% of melanoma cells.
Conclusion:  An altered nuclear nucleolin expression seems to accompany melanoma progression. Further investigation on nucleolin functionality and subcellular trafficking could add information on its altered role in melanoma.  相似文献   
2.
The "golden path", produced by the Human Genome Project effort, is composed of a collection of overlapping and fully sequenced BAC/PAC clones covering almost completely the human genome. These clones can be advantageously exploited as fluorescence in situ hybridization (FISH) probes for the characterization of rearrangements frequently found in tumors. Breakpoint characterization can be further refined by generating additional smaller FISH probes through LONG-PCR amplification of specific DNA segments, 5-10 kb in size, using appropriate BAC/PAC probes as template. We report here an example of this approach that has been used to characterize a complex Ph-negative chronic myeloid leukemia (CML Ph-) case in which the BCR/ABL fusion gene was found located on chromosome 9.  相似文献   
3.
Double minutes (dmin), the cytogenetic hallmark of genomic amplification, are found in approximately 1% of karyotypically abnormal acute myeloid leukemias (AML) and myelodysplastic syndromes (MDS). The MYC gene at 8q24 has been reported to be amplified in the majority of the cases, and generally it has been assumed that MYC is the target gene. However, only a few studies have focused on the extent of the amplicon or on the expression patterns of the amplified genes. We have studied six cases (five AML and one MDS) with MYC-containing dmin. Detailed fluorescence in situ hybridization analyses identified a common 4.3 Mb amplicon, with clustered proximal and distal breakpoints, harboring eight known genes (C8FW, NSE2, POU5FLC20, MYC, PVT1, AK093424, MGC27434 and MLZE). The corresponding region was deleted in one of the chromosome 8 homologues in five of the six cases, suggesting that the dmin originated through extra replication (or loop-formation)--excision--amplification. Northern blot analysis revealed that MYC was not overexpressed. Instead, the C8FW gene, encoding a phosphoprotein regulated by mitogenic pathways, displayed increased expression. These results exclude MYC as the target gene and indicate that overexpression of C8FW may be the functionally important consequence of 8q24 amplicons in AML and MDS.  相似文献   
4.
Chromosomal rearrangements of the MYC locus, which often involve the IG loci, are recurrent events in multiple myeloma (MM) and plasma cell leukemia (PCL). We used dual-color fluorescence in situ hybridization (FISH) to characterize the breakpoint locations of chromosomal translocations/rearrangements involving the MYC locus at 8q24 found in a panel of 14 MM cell lines and 70 primary tumors (66 MM and 4 PCL). MYC locus alterations were observed in 21 cases: MYC/IG (mainly IGH@) fusions in 11 cell lines and three patients (2 MM and 1 PCL), and extra signals and/or abnormal MYC localizations in seven patients (5 MM and 2 PCL). Fourteen of these cases were investigated by FISH analyses by use of a panel of BAC clones covering about 6 Mb encompassing the MYC locus. The breakpoints were localized in a region 100-250 kb centromeric to MYC in four cases, a region 500-800 kb telomeric to the gene in four cases, and regions > or = 2 Mb centromeric or telomeric to MYC in five cases. Two different breakpoints were detected in the KMS-18 cell line, whereas the insertion of a MYC allele was found in a complex t(16;22) chromosomal translocation in the RPMI8226 cell line. Our data document a relatively high dispersion of 8q24 breakpoints in MM.  相似文献   
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6.
Background and purpose: The pathology of neuropsychological deficits in Parkinson’s disease (PD) is incompletely defined. Methods: We investigated cortical thickness and neuropsychological performances in non‐demented patients with PD and healthy controls. Results: Patients showed significant cortical thinning in right middle temporal and left fusiform cortices. Verbal memory performance was related with left fusiform thinning. Conclusions: Cognitive and cortical changes in non‐demented patients with PD are detectable and clearly related.  相似文献   
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8.
Duodenal ulcer is a chronic disease, punctuated by acute relapses. The pathogenic mechanism in 90-100% of cases is infection by Helicobacter pylori. Two major strains exist of this bacterium: I strain, which secretes a vacuolating cytotoxin (Vac-A), and another protein named cytotoxin-associated (Cag-A) and type II strain, unable to produce both proteins and unable to produce duodenal pathology. We sought to identify the natural history of relapsing duodenal ulcer after cure of the bacterial infection. In particular, we followed the outcome of patients who repeatedly had bled from their recurrent ulcer disease, after success in eliminating the microorganism from the stomach. None of 12 repeated bleeders had an ulcer recurrence after the cure of Helicobacter pylori infection. Only 3 (5%) of 60 frequent relapser had a new episode of duodenal ulcer during a follow-up reinfection by Helicobacter pylori. We demonstrated that the cure of bacterial infection is also the cure of duodenal ulcer recurrence, but for a few cases, in the latter, event one could hypothesize a defect in the production of growth factors (Epidermal Growth Factor, Fibroblast Growth Factor) or of cellular polyamines synthesis. It is important to improve the diagnosis of reinfection by implementing the urea breath test.  相似文献   
9.
The recent hypothesis that postnatal microglia are maintained independently of circulating monocytes by local precursors that colonize the brain before birth has relevant implications for the treatment of various neurological diseases, including lysosomal storage disorders (LSDs), for which hematopoietic cell transplantation (HCT) is applied to repopulate the recipient myeloid compartment, including microglia, with cells expressing the defective functional hydrolase. By studying wild-type and LSD mice at diverse time-points after HCT, we showed the occurrence of a short-term wave of brain infiltration by a fraction of the transplanted hematopoietic progenitors, independently from the administration of a preparatory regimen and from the presence of a disease state in the brain. However, only the use of a conditioning regimen capable of ablating functionally defined brain-resident myeloid precursors allowed turnover of microglia with the donor, mediated by local proliferation of early immigrants rather than entrance of mature cells from the circulation.  相似文献   
10.
Primary lymphoma of the female genital tract is very rare. We report the case of a 36-year-old woman who was referred to our hospital because of an indeterminate Pap smear test. The colposcopy showed a thickening of the posterior vaginal wall and various irregular ulcerated nodular lesions. Histological examination, immunohistochemistry and the staging procedures were conclusive of diffuse large B-cell lymphoma of the vagina, stage IEA. Complete remission was achieved after 6 cycles of immunopolychemotherapy (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone). No relapse has occurred during a follow-up of 71 months. Moreover, we reviewed the 62 previously reported cases of primary extranodal non-Hodgkin's lymphoma of the vagina, focusing on clinicopathological and therapeutic aspects, to better characterize this unusual disease.  相似文献   
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