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41.
A series of 3-acyl derivatives of the dihydronaphtho[2,3-b]thiophen-4,9-dione system were studied with respect to cytotoxicity and topoisomerase II inhibitory activity. These analogues were designed as electron-deficient anthraquinone analogues with potential intercalation ability. Derivatives 3-(diethylamino)-N-(4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophen-3-yl)propanamide (11m) and 3-(2-(dimethylamino)ethylamino)-N-(4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophen-3-yl)propanamide (11p) showed a high efficacy in cell lines that were highly resistant to treatment with doxorubicin, such as MDA-MB435 (melanoma), IGROV (ovarian), and SF-295 (glioblastoma) human cell lines. Both compounds inhibit topoisomerase II mediated relaxation of DNA, while only 11p incites arrest at the S phase in Caco-2 cells, inducing a delay of cell cycle progression and an increase of cell differentiation. The ability of these derivatives to modulate small heat shock proteins and cardiotoxicy effects was also explored. In addition, the DNA-binding properties of these compounds were investigated and discussed.  相似文献   
42.
In the clinical literature there are few specific studies about the relationship between cognition processes and sleep during childhood. In addition, milder deficits in general intellectual capacity have received less attention relative to major cognitive dysfunctions (such as the genetic or environmental basis of mental retardation), especially concerning the low normal and borderline status. Sleep could play a key role in multiple intellectual abilities such as memory, executive functions, and school performances. Aim of our study is to assess the sleep macrostructure and NREM instability (cyclic alternating pattern) and their relationship with IQ in a sample of subjects with borderline intellectual functioning (BIF). The DSM-IV defines BIF as a total intelligence quotient (TIQ) ranging between 71 and 84. Intellective functioning was assessed using the Italian version of Wechsler Intelligence Scale for Children-Revised (WISC-R), a well validated test for the developmental age between 6 and 16. For this study, 12 BIF and 17 healthy children, matched for sex and age, underwent an overnight PSG recording. Macrostructural sleep and CAP analysis were also performed. To our knowledge, this study represents the first attempt to evaluate sleep architecture and NREM instability organization in children with BIF. Findings from this investigation evidence that BIF presents alterations in both macro- and microstructural sleep architecture, with an interesting statistical significant correlation with IQ.  相似文献   
43.
44.

Purpose

Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurodegenerative disorder characterized by cerebellar ataxia, supranuclear ophthalmoplegia, and peripheral neuropathy. Autonomic nervous system dysfunction is often present. This study evaluated the cardiac sympathetic function in patients with SCA2 using 123I-metaiodobenzylguanidine (MIBG) in comparison with patients with Parkinson’s disease (PD) and control subjects.

Methods

Nine patients with SCA2, nine patients with PD, and nine control subjects underwent 123I-MIBG imaging studies from which early and late heart-to-mediastinum (H/M) ratios and myocardial washout rates were calculated.

Results

Early (F?=?12.3, p?<?0.0001) and late (F?=?16.8, p?<?0.0001) H/M ratios were significantly different among groups. In controls, early and late H/M ratios (2.2?±?0.12 and 2.1?±?0.20) were significantly higher than in patients with SCA2 (1.9?±?0.23 and 1.8?±?0.20, both p?<?0.05) and with patients with PD (1.7?±?0.29 and 1.4?±?0.35, both p?<?0.001). There was also a significant difference in washout rates among groups (F?=?11.7, p?<?0.0001). In controls the washout rate (19.9?±?9.6 %) was significantly lower (p?<?0.005) than in patients with PD (51.0?±?23.7 %), but not different from that in SCA2 patients (19.5?±?9.4 %). In SCA2 patients, in a multivariable linear regression analysis only the Scale for the Assessment and Rating of Ataxia score was independently associated with early H/M ratio (β?=??0.12, p?<?0.05).

Conclusion

123I-MIBG myocardial scintigraphy demonstrated an impairment of cardiac sympathetic function in patients with SCA2, which was less marked than in PD patients. These results suggest that 123I-MIBG cardiac imaging could become a useful tool for analysing the pathophysiology of SCA2.  相似文献   
45.
Forensic and archaeological examinations of human skeletons can provide us with evidence of violence. In this paper, we present the patterns of two cranial lesions found on an adult male (T173) buried in a grave in the necropolis ‘Isolato 96’, Messina, Sicily, dating back to the Roman Empire (1st century BC - 1st century AD). The skull reveals two perimortem traumatic lesions, one produced by a sharp object on the right parietal bone and the other one on the left parietal bone, presumably the result of a fall. The interpretation of fracture patterns found in this cranium are an illustration of how forensic approaches can be applied with great benefit to archaeological specimens.  相似文献   
46.
Myelin oligodendrocyte glycoprotein (MOG), a minor myelin component, is an important central nervous system specific target autoantigen for primary demyelination in autoimmune diseases such as multiple sclerosis (MS). The native structure of MOG presents a glycosylation site at position 31 (Asn(31)). It has been recently described that glycosylation of a MOG peptide epitope improved the detection of specific autoantibodies in sera of MS patients. The solution conformational behavior of two MOG derived peptides-hMOG(30-50) (1) and the glycosylated analogue [Asn(31)(N-beta-Glc)]hMOG(30-50) (2)-were investigated through NMR analysis in a water/HFA solution. Conformational studies revealed that peptides 1 and 2 adopted similar conformations in this environment. In particular, they showed strong propensity to assume a well-defined amphipatic structure encompassing residues 41-48. The N-terminal region resulted to be almost completely unstructured for both peptides. The presence in 1 of a low populated Asx-turn conformation characteristic of the Asn-Xaa-Thr glycosylation sites was the only conformational difference between peptides 1 and 2. Thus, the specific antibody recognition of peptide 2 is most likely driven by direct interactions of the antibody binding site with the Asn-linked sugar moiety.  相似文献   
47.
48.
Beta 2-microglobulin (B2m) was measured on serum samples in 274 patients with acute and chronic lymphoproliferative disorders (85 non-Hodgkin lymphomas-NHL, 30 Hodgkin lymphomas-HL, 34 B-cell chronic lymphocytic leukemias-B-CLL, 8 Waldenstr?m macroglobulinemias-WM, 76 multiple myelomas-MM, 31 acute lymphoblastic leukemias-ALL, 10 hairy cell leukemias-HCL). Two hundred and four patients were studied at the time of diagnosis, and results were correlated to clinical stage, and histologic subtype in NHL, immunoglobulin type in MM, and immunologic phenotype in ALL. Moreover, B2m was tested during and after chemo- and/or radiotherapy, and results were correlated to response, progression or relapse. Elevated pretreatment B2m values were found in widespread forms of NHL and HL, in patients with B symptoms and in the unfavorable histologic subgroups of NHL. Rapid falls in levels followed therapy institution. In B-CLL and in MM a close relationship between B2m and cell mass was found. A significant B2m level reduction followed treatment, whereas its increase could detect a relapse. In ALL, serum B2m was only slightly above the normal range. B2m seems to reflect the total burden of malignant cells mainly in MM and B-CLL; in other lymphoproliferative disorders it provides less prognostic information.  相似文献   
49.
Background: In chronic renal failure, desferrioxamine (DFO) may improve erythropoiesis independent from its aluminium (Al) chelating effect. The mechanism of this action is still unknown. Methods: To verify whether DFO influences proliferation of erythropoietic precursors, we studied 10 patients on chronic haemodialysis, free from malignancies or other haematological diseases, iron deficiency, bone marrow fibrosis, and Al toxicity. Al accumulation was excluded by the DFO test. Peripheral blood samples were drawn for basal burst-forming unit-erythroid (BFU-E) assay. Mononuclear cells were isolated by density gradient centrifugation with Ficoll-Hypaque, and incubated for 15 days with three different experimental conditions: (a) low-dose recombinant human erythropoietin (rHuEpo) (3 U/ml); (b) high dose rHuEpo, (30 U/ml); (c) both DFO (167 &mgr;g/ml) and rHuEpo (3 U/ml). We determined TIBC, transferrin, ferritin, reticulocytes, hypochromic erythrocytes, soluble transferrin receptor (sTR), haemoglobin (Hb), and haematocrit (Hct) at baseline and then every 14 days. Patients received 5 mg/kg DFO infused during the last hour of each dialysis session for 6 weeks; six patients remained in the study for an additional 6 more weeks. BFU-E assays were set up after 6 and 12 weeks of DFO therapy. Results: At baseline DFO had small effect on BFU-E proliferation (33.9±25 vs 30.4±25.9) and high-dose rHuEpo had a significant effect (45.15±27 vs 30.4±25.9, P<0.01). After 6 weeks of DFO therapy a significant increase in BFU-E proliferation was observed in all culture conditions (78.25±32 vs 30.45±25.9 standard culture, P<0.01; 110.9±30 vs45.15±27 high dose rHuEpo, P<0.01; 98.75±32 vs 45.15±27 DFO culture, P<0.01). Moreover, the increase in BFU-E proliferation was significant greater with DFO culture than standard culture (P<0.01). The same trend was found at the third BFU-E assay, performed in only six patients, when all culture conditions showed a further increase of erythroid precursor proliferation. However, the DFO culture was not significantly greater than the standard culture, while the high-dose rHuEpo was significantly greater than the DFO culture. Patients in group 1 (n=10), had a significant increase in reticulocytes (1.5±0.6 vs 1.72±0.3, P<0.01) and of hypochromic erythrocytes (HE) (5.6±5.1 vs 14.4±12.7, P<0.01), while sTR, Epo, Hb, and Hct were only minimally increased. Ferritin decreased significantly (448±224 vs 196±215, P<0.01) and TIBC and transferrin were unchanged. Conclusions: Thus DFO increases erythroid activity by BFU-E proliferation and increases reticulocytes in haemodialysis patients. Such an effect may be related to increased iron utilization. DFO may be a useful tool for anaemic patients with good iron stores and without Al overload. Key words: desferrioxamine; erythroid progenitors; erythropoiesis; haemodialysis   相似文献   
50.
P-glycoprotein (P-170) is the phenotypic marker of tumoral cells that show the phenomenon of multidrug resistance (MDR). Using an immunocytochemical approach, we employed the monoclonal antibody C219 (which recognizes an epitope of such a glycoprotein) to evaluate in cytologic samples the expression of P-170 on neoplastic cells from 52 patients affected by different hematologic malignancies and its eventual correlation to clinical outcome. Longitudinal studies were also performed in 14 patients. Results obtained demonstrated that a) the so-called "MDR phenotype" may be heterogeneously represented (from less than 1 to 100% of positive cells) in hemopoietic tumors at diagnosis (without exposure to pharmacologic agents), as well as during the course of the disease, although a more substantial presence of P-170 occurred in treated patients. There was no correlation between neoplastic kinetic activity (such as expression of Ki 67 recognized nuclear proliferation-associated antigen) and P-170-positive cells. b) Percentage of positive cells as well as intensity of staining seemed to be important in determining MDR; in general, there was a strong correlation between expression of P-170 in more than 20% of neoplastic cells and a lack of response to chemotherapy. However, some false-positive and false-negative cases were observed. c) The detection of scattered P-170-positive cells may predict a pharmacologic selection of intrinsic or mutant-resistant clones.  相似文献   
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