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61.
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CONTEXT: Anaplastic thyroid carcinoma (ATC) is one of the most aggressive types of cancer characterized by complete refractoriness to multimodal treatment approaches. Therapeutic strategies based on the simultaneous use of proteasome inhibitors and death receptor ligands have been shown to induce apoptosis in several tumor types but have not yet been explored in ATC. OBJECTIVE AND METHODS: The aim of this study was to investigate the ability of the proteasome inhibitor Bortezomib to induce apoptosis in ATC cell lines. Bortezomib was used as a single agent or in combination with TNF-related apoptosis-induced ligand (TRAIL), a member of the TNF family that selectively induces tumor cell apoptosis. The molecular effects of Bortezomib were investigated by analyzing the expression of key regulators of cell cycle and apoptosis and the activation of different apoptotic pathways. RESULTS: Bortezomib induced apoptosis in ATC cells at doses achieved in the clinical setting, differently from conventional chemotherapeutic agents. Simultaneous treatment with low doses of Bortezomib and TRAIL had a synergistic effect in inducing massive ATC cell apoptosis. Bortezomib increased the expression of cytotoxic TRAIL receptors, p21 (WAF/CIP1) and proapoptotic second mitochondria-derived activator of caspases/direct inhibitor of apoptosis binding protein with low pI, and reduced the expression of antiapoptotic mediators such as cellular Fas-associated death domain-like IL-1beta converting enzyme inhibitory protein, Bcl-2, Bcl-X(L), and inhibitor of apoptosis-1, thus resulting in cell death induction through the mitochondrial apoptotic pathway. CONCLUSIONS: The combination of proteasome inhibitors and TRAIL synergizes to induce the destruction of chemoresistant neoplastic thyrocytes and could represent a promising therapeutic strategy for the treatment of anaplastic thyroid carcinoma.  相似文献   
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Present transfusional regimen protocols increase the life expectancy of patients with beta-thalassemia major, but cause a progressive iron overload that can be prevented or limited only by appropriate iron chelation. Siderosis is responsible for the clinical complications of the disease. Short stature and hypogonadism are extremely frequent in patients with thalassemia. Many factors are responsible for short stature in patients with thalassemia, the most important of which are dysfunction of the GH-IGF-I axis and desferoxamine (DFX)-induced bone dysplasia. Hypogonadism is the most frequent endocrine complication, mostly due to gonadotrophins deficiency secondary to iron overload. Sex steroid treatment for induction of puberty and/or maintenance of sexual characteristics is necessary. Both short stature and hypogonadism are present in a significant percentage of bone marrow transplanted patients with thalassemia. Factors responsible for short stature are previous iron overload, liver impairment, DFX treatment, and toxicity of chemotherapeutic agents. In some patients absence of pubertal development is due to gonadotropin insufficiency, probably secondary to previous iron overload; other patients exhibit hypergonadotrophic hypogonadism due to the toxic effect of chemotherapeutic agents on the gonads. Both groups need hormonal replacement therapy. These data support the need for vigilant follow-up of patients with thalassemia before and after transplantation, in order to treat endocrine dysfunctions at the appropriate age.  相似文献   
65.
Focal contacts are systems of adherens junctions of the cell-extracellular matrix type, which allow the transfer of fundamental signals from the extracellular matrix to nuclear compartments, capable of regulating adhesion, proliferation, migration and differentiation of cells. Recently, many authors have concentrated their attention on epitheliomesenchymal interactions which guide organogenesis of dental germ, identifying numerous growth and differentiation factors and having the inner enamel epithelial cells of the enamel organ as a target. Given that the two cellular compartments in their tooth germ are separated by a basal membrane and by an extracellular matrix, which touches it, we wanted to evaluate the presence of focal contacts through the identification of talin and vinculin, proteins of the actin-associated protein complex. In this study we utilized the hemimandibles of young Wistar rats and we extracted the related odontogenic tooth organs present at their apical end. Specimens are processed with antibody against vinculin and talin. Results show that these junctional system proteins are present at the apical poles of both cellular compartments suggesting that putative epithelial-mesenchymal interactions, other than marker molecules, may use focal contacts as a system for transmission of signals.  相似文献   
66.
A comparative study on peracetic acid and sodium hypochlorite in inactivating bacteria and viruses was carried out. Therefore the disinfection actions of peracetic acid, in comparison with sodium hypochlorite, was evaluated against the usual indicators of faecal contamination, the pathogen Salmonella, Pseudomonas spp., bacteriophages anti-Escherichia coli, F+/phage and the phage of Bactericides fragilis B40-8 and enteroviruses. Under the experimental conditions, no representative results were obtained for enteroviruses and phages because of their low concentration in the sewage effluent. On the other hand, the indicator organisms were reduced substantially by the sodium hypochlorite and peracetic acid concentrations, while more variable results were obtained against Pseudomonas and bacteriophages anti-Escherichia coli.  相似文献   
67.
The Italian Oncology Group for Clinical Research tested two experimental chemotherapy strategies in an attempt to improve the results achievable with conventional chemotherapy in metastatic breast cancer. One hundred sixty-two patients were randomly allocated as follows: (a) to the conventional cyclophosphamide, methotrexate, 5-fluorouracil chemotherapy regimen (CMF); (b) to a rotational crossing program (ROT-CROSS); or (c) to a sequential intensification program (SEQ-INT). The same single agents (C, M, F, cisplatin, etoposide, and doxorubicin) were administered in both experimental arms, but following a different policy. The SEQ-INT program induced a significantly higher complete response (32% vs. 6%, p = 0.0006) and objective response rate (72% vs. 42%, p = 0.0047) than CMF did. There were no differences in survival between CMF and either experimental arm. A number of side effects were significantly more with both experimental chemotherapies than with CMF, but the treatments were generally tolerable. Although some caution is required when interpreting a significant advantage found between an entire chemotherapeutic strategy and a single conventional combination, this study documents the potential therapeutic advantage of administering different sequential chemotherapies, and changing each at the time of maximum result without waiting for a progression. The impressive cytoreductive effects achievable with this policy (SEQ-INT) in metastatic disease merit further investigation in the adjuvant setting.  相似文献   
68.
Laparoscopic gastric resections   总被引:1,自引:0,他引:1  
The impressive breakthrough in laparoscopic surgery has pushed surgeons to perform gastric resection through such an approach. Laparoscopy reduces the surgical stress and the postoperative pain and has a positive impact on the rehabilitation time, the hospital stay, and return to work and social activities. Laparoscopic partial gastrectomy for benign diseases and for palliation has been accepted as an effective surgical option: they are reproducible operations performed worldwide at a more and more rapid pace. Laparoscopic gastric resections and laparoscopically assisted gastric resections for malignancy deserve a word of caution. Nevertheless, the investigators report their series of laparoscopic subtotal and distal gastrectomies for cancer with medium and long-term results comparable with those of open surgery. Furthermore, new and less invasive surgical options have been recently introduced. Full and partial thickness local resections may be accomplished through intragastric procedures, for treatment of small benign tumors and early stage gastric cancer.  相似文献   
69.
OBJECTIVE: To study the effects of monotherapy with leucocyte interferon-alpha (IFNalpha) versus IFNalpha + ribavirin in patients with chronic hepatitis C who were nonresponders to previous courses of recombinant or lymphoblastoid IFNalpha. DESIGN AND SETTING: This was a nonblind randomised study of outpatients at 3 centres in Palermo, Sicily, Italy. PATIENTS AND PARTICIPANTS: We recruited 72 patients (48 males, 24 females), mean age 48.8 +/- 6.6 years (range 31 to 63 years), with biopsy-proven chronic hepatitis C, predominantly genotype 1b. INTERVENTIONS: 24 patients (group A) received IFNalpha 6MU 3 times weekly for 6 months, and 48 patients (group B) received IFNalpha 6MU 3 times weekly + ribavirin 1200 mg/day for 6 months. ALT levels and adverse effects were monitored monthly, and hepatitis C virus (HCV) RNA levels were measured at study entry, at the end of treatment and after a 6-month follow-up. RESULTS: At baseline all patients were HCV-RNA positive and had ALT levels greater than twice normal. Mean post-treatment serum HCV-RNA levels were below baseline in group A, but the virus was eradicated in only 1 patient; 6 patients had normalised serum ALT levels. In group B at end of treatment, 12 patients were negative for HCV-RNA and serum ALT levels were normal in 18. At follow-up, all group A patients had elevated ALT levels and positive HCV-RNA. In group B, 3 patients were still negative for HCV-RNA and 4 had normal ALT. In 4 patients in group B, therapy was suspended because of anaemia, depression and decrease in neutrophil count; a flu-like syndrome was recorded with no frequency difference between groups. CONCLUSIONS: These results suggest that patients with chronic hepatitis C unresponsive to IFNalpha monotherapy could benefit from combination therapy with IFNalpha + ribavirin.  相似文献   
70.
The vinculin-talin-integrin system and the dystrophin-glycoprotein complex (DGC) are two protein systems with structural and signaling functions, allowing interaction between muscle fibers and extracellular matrix. Although numerous studies have been conducted on these systems, their localization and distribution patterns along the nonjunctional sarcolemma are not clear. On this basis, we carried out an indirect immunofluorescence study on the vastus lateralis muscle of human adults not affected by neuromuscular diseases to better define these patterns. Our results showed that all tested proteins of the two systems have a costameric distribution; all tested proteins of the two systems colocalize with each other (about 90-95% of the cases); only alpha-sarcoglycan in a few cases (about 6%) does not colocalize with other proteins; in about 9-10% of the cases, dystrophin and beta-dystroglycan colocalize partially with other proteins; all tested proteins can be localized in different fibers, both in the region of the sarcolemma over I or A bands. The colocalization between the vinculin-talin-integrin and DGC systems may imply their functional interaction involving the structural aspect, by providing a stronger adhesion between sarcolemma and extracellular matrix in well-defined regions of the muscle fiber. Besides, their colocalization may suggest the existence of a mechanism of mutual modulation of the transmitted signals. This reciprocal control may determine, in different conditions, the prevalence of one system over another with a consequent transmission of different messages to the sarcolemma-associated cytoskeleton.  相似文献   
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