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41.
We designed an open, non-randomized clinical study to assess as the first endpoint the feasibility of sparing surgery and of preserving organ/function by using neo-adjuvant chemotherapy (NAG) in oral cavity and oropharynx cancer patients, and, as the second endpoint, the clinical response to this treatment approach and its duration. Moreover, an attempt was made to scale the extent of surgery by means of an Arbitrary Scale assigning different percentages to the different extents of surgical resection. Twenty-five patients with primary oral cavity and oropharynx cancer (stage III-TV) were enrolled in the study and were assigned to either the classical Al-Sarrafs regimen (1) (n=15) or to a regimen (2) consisting of cisplatin 80 mg/m(2) i.v. on day 1, 5-FU 600 mg/m(2) on days 2-5 and vinorelbine 20 mg/m(2) on days 2 and 8 (n=10). The 25 patients were all evaluable for response to NAC and 20 of them were evaluable for organ preservation. The overall response (OR) rate was 86.6% (13/15 patients) for regimen 1 (cisplatin + 5-FU) and 80% (8/10 patients) for regimen 2 (cisplatin + 5-FU + vinorelbine). The median follow-up duration was 20.6 months. 5/20 (25%) patients completely avoided surgery, 5/20 (25%) patients had a reduced extent of surgical resection, while: 10/20 (50%) patients received the previously planned surgical resection. Altogether, 10/20 (50%) patients treated with NAC either avoided or achieved a reduction in the previously planned surgical resection. Moreover, organ function was evaluated to support the assessment of treatment outcome in our patients. For this purpose we selected the Performance Status Scale for Head and Neck Cancer Patients: as expected, no significant impairment was detected in the area of comprehensibility of speech, but we were rather surprised that no significant impairment was found in the two areas of eating in public and normalcy of diet. NAG-associated toxicity was moderate and similar in the two chemotherapy regimens. The most relevant contributions offered by our study are represented by i) a Scale aimed at measuring as precisely as possible the reduction of surgical resection made possible by NAC compared to surgery planned before NAC and ii) an attempt to support the results with an assessment of treatment outcome.  相似文献   
42.
Monocytes were separated from peripheral blood mononuclear cells of normal human donors by adherence on plastic conditioned by cell lines (microexudate-coated plastic) and harvested by exposure to ethylene diamine tetra-acetic acid. Cytolytic activity was tested by incubating effector cells for 48 h with the murine SV40-transformed TU5 kidney line or the human lung cancer-derived CaLu line prelabelled with tritiated thymidine. Lymphokine-containing supernatants were obtained from in vitrocultures of lymphoid cells with phytohemagglutinin (PHA), purified protein derivative (PPD), or with Corynebacterium parvum strains CN6134 or CNS888. The monocytes had significant levels of spontaneous cytotoxicity and exposure to lymphokine supernatants markedly enhanced their tumoricidal activity. Augmentation of monocyte-mediated cytotoxicity required a minimal exposure to lymphokine supernatants for 4 h and was maximal after 24 h of preincubation. Treatment of the effector cells with anti-human T-cell serum and complement did not affect either their spontaneous or their lymphokine-stimulated cytotoxicity, whereas silica impaired both reactivities. Supernatants of cultures with PHA, PPD and C. parvum CN6134 had significant levels of interferon (IF). Since partially purified human fibroblast or leukocyte IF was able to stimulate monocyte-mediated cytotoxicity, the IF in these supernatants could play some role in the stimulation of the monocytes. However, C. parvum CN5888 supernatants, which had little IF, enhanced monocyte cytotoxicity as effectively as the C. parvum CN6134 supernatants, strongly suggesting that lymphocyte mediators other than IF can augment the tumoricidal activity of these effector cells. Mature macrophages obtained by in vitro cultivation of monocytes for 4-7 days retained natural cytolytic activity and showed enhanced cytotoxicity in the presence of lymphokines. However, more prolonged in vitro cultivation (> 10 days) resulted in cultures of epithelioid and multinucleated cells which had little natural cytotoxicity and were not responsive to lymphokines.  相似文献   
43.
The aim of the present study was to verify whether the CMI response of the host's lymphocytes is directed towards tumor-associated antigens (TAA) specific for each histological type of tumor. The leucocyte migration inhibition (LMI) test was selected for this purpose, utilizing the cancer patients' leucocytes and, as neoplastic antigens, formalin-fixed cells of surgically removed cancer tissue. Two hundred and eighteen patients were studied, 110 of whom were affected by breast cancer, 48 by digestive tract and 60 by laryngeal cancer. The total amount of tests performed was 278. The leucocytes of 93 normal subjects were tested against the different tissues' cancer antigens, as were the leucocytes of 41 patients with cancer of different organs tested against the corresponding normal tissues' antigens. The breast cancer patients (122 tests performed) showed 82.35% positive tests against homologous antigen, 72.72% and 95.24% against heterologous (digestive tract and laryngeal cancer, respectively) antigens. The digestive tract cancer patients (69 tests performed) showed 70.27% positive tests against homologous, 66.66% and 43.48% against heterologous antigens (breast and laryngeal cancer respectively). The laryngeal cancer patients (87 tests performed) showed 74.29% positive tests against homologous, 38.10% and 80.65% against heterologous antigens (breast and digestive tract, respectively). The results led to the conclusion that the LMI test response of cancer patients was not "tissue specific": the test did not discriminate between the homologous and the heterologous cancer antigens, and it seems that the response was not directed towards specific TAA but only towards wide-range or "group" TAA, showed by several types of tumors.  相似文献   
44.
The radial transport across the wall of expanded polytetrafluoroethylene (ePTFE) arterial prostheses has a significant effect on lipid uptake observed in prostheses implanted in humans, which has been postulated to be one of the causes associated with implant failure. The goal of this study was to stimulate radial transport on a lipidic dispersion across the wall of an ePTFE prosthesis and investigate its effects on the circumferential mechanical properties of the prosthesis. An in vitro model was developed to simulate the lipidic radial transport across the wall. Lipids contained in a phosphatidylcholine dispersion were used as the transported molecules. Lipid concentration profiles were obtained after exposing commercial ePTFE prostheses to various transmural pressure and/or lipidic concentration gradients. Phospholipids gradually accumulated up to the external reinforcing wrap of the prosthesis, which clearly acted as a rigid barrier against lipid infiltration. Tensile tests performed on the virgin samples showed that the wrap was much more rigid than the microporous part of the prosthesis. After the lipid simulation, the rigidity of the wrap decreased with respect to what was observed for the virgin prosthesis. Finally, some clinical implications of this phenomena are discussed.  相似文献   
45.
The serum levels of interleukin-(IL-)1α, IL-1β, IL-2, IL-6, TNFα, and sIL-2R and the proliferative response of peripheral blood mononuclear cells (PBMC) to phytohemagglutinin (PHA), anti-CD3 monoclonal antibody (mAb), recombinant IL-2 (rIL-2), and the combination of PHA or anti-CD3 mAb with rIL-2 were studied and correlated with serum levels of C-reactive protein (CRP) in women with advanced epithelial ovarian cancer. The expression of CD25 and CD122 subunities of membrane-bound IL-2R on PHA- or anti-CD3 mAb-stimulated PBMC was also studied. In comparisons with the controls, PBMC response to PHA, anti-CD3 mAb, and rIL-2 was significantly lower in the cancer patients. The addition of exogenous rIL-2 to the PBMC cultures increased response in both controls and patients but did not modify the significance of the differences. After stimulation with PHA or anti-CD3 mAb, the percentage of PBMC CD25+or CD122+was significantly lower in patients. The serum levels of IL-1α, IL-1β, IL-6, TNFα, sIL-2R, and CRP were significantly increased in patients compared to the controls. Instead, no differences were observed for serum levels of IL-2. A strong association was found between high serum levels of the above-mentioned cytokines, sIL-2R, and CRP. The results of our study on advanced stage (IIIb–IV) ovarian cancer patients are consistent with the previously reported hypothesis that high IL-6 and/or CRP serum levels may represent an important and independent prognostic factor of the likely outcome in cancer patients.  相似文献   
46.
Some studies have demonstrated antidepressant activity of neurokinin-1-receptor antagonists (NK-1-RA) in major depressive disorder. However, the underlying mechanisms of this antidepressant effect are largely unknown. Preclinical studies in rats and mice have suggested that NK-1-RA do increase the neuronal release of serotonin (5-HT). This, however, seems to be compensated by an increased 5-HT reuptake, indicating that NK-1-RA have no inhibitory effect on the 5-HT transporter in rodents. Given the possibility that modulation of neurotransmitter release and reuptake may differ between species, with major differences found between rodents and humans, we investigated for the first time the possible modulatory effect of NK-1-RA on 5-HT uptake in human brain synaptosomes and compared it with the situation in rat cortex. We found that the specific human NK-1-RA L-733060, in contrast to the SSRI fluvoxamine (IC50 = 10− 7.96 M) did not inhibit 5-HT uptake in human brain synaptosomes and did not modulate fluvoxamine-induced 5-HT uptake inhibition at 1 μM. Furthermore, substance P as well as Sar9Met(O2)11SP, as the major agonists at the NK-1-R, did not modulate 5-HT uptake in human brain synaptosomes. Similar results were found in rat cortex synaptosomes by using the rat-specific NK-1-RA WIN51708. These results show that in humans, as in rodents, inhibition of the 5-HT transporter is probably not the underlying mechanism of the assumed antidepressant activity of NK-1-RA.  相似文献   
47.
Mucoepidermoid Carcinoma (MEC) it can origin from a mandibular odontogenic cyst. We report the case of a 63‐year‐old man with MEC of the right retromolar trigonum of the mandibula. We performed a wide mandibular excision and immediate reconstruction with a fibula bone free flap.  相似文献   
48.
Chemical food poisoning is a periodic menace both for the health of the consumers and for trade. It can be intentional or unintentional. In the latter case, poisoning may have a very large attack rate and it may be caused by sophistication (e.g., the methanol poisoning in Italy in 1985) or by environmental pollution (e.g., the Iraq accident in 1971-1972 due to mercury-contaminated flour). As a general statement, they are acute events, often noticed by outbreaks of unexplained deaths or sickness. The purposed lines for intervention (monitoring and biological testing) and some related problems are briefly described. Emphasis is placed on biological of suspected food items by a sensitive method to detect the presence of a noxious agent of unknown origin. The basic principle is to administer the highest amount possible of the suspected food to two different species of rodents for 5 days. Finally it should be noted that the characteristics and severity of every episode depend on the food and the chemical involved; thus only general suggestions may be given.  相似文献   
49.
Chest tubes are routinely inserted after thoracic surgery procedures in different sizes and numbers. The aim of this study is to assess the efficacy of Smart Drain Coaxial drainage compared with two standard chest tubes in patients undergoing thoracotomy for pulmonary lobectomy. Ninety-eight patients (57 males and 41 females, mean age 68.3 ± 7.4 years) with lung cancer undergoing open pulmonary lobectomy were randomized in two groups: 50 received one upper 28-Fr and one lower 32-Fr standard chest tube (ST group) and 48 received one 28-Fr Smart Drain Coaxial tube (SDC group). Hospitalization, quantity of fluid output, air leaks, radiograph findings, pain control and costs were assessed. SDC group showed shorter hospitalization (7.3 vs. 6.1 days, p = 0.02), lower pain in postoperative day-1 (p = 0.02) and a lower use of analgesic drugs (p = 0.04). Pleural effusion drainage was lower in SDC group in the first postoperative day (median 400.0 ± 200.0 mL vs. 450.0 ± 193.8 mL, p = 0.04) and as a mean of first three PODs (median 325.0 ± 137.5 mL vs. 362.5 ± 96.7 mL, p = 0.01). No difference in terms of fluid retention, residual pleural space, subcutaneous emphysema and complications after chest tubes removal was found. In conclusion, Smart Drain Coaxial chest tube seems a feasible option after thoracotomy for pulmonary lobectomy. The SDC group showed a shorter hospitalization and decreased analgesic drugs use and, thus, a reduction of costs.  相似文献   
50.
The present study was designed to investigate the adverse reproductive effects of acetamiprid, besides the possible protective role of Nigella sativa oil (NSO), as a potential antioxidant agent. Thirty-two male Wistar rats were allocated into four equal groups of eight, control (CRL), acetamiprid (ACMP, 27?mg/kg), Nigella sativa oil (NSO, 0.5?ml/kg) and in combination (ACMP?+?NSO). The experimental animals were dosed by gavage (5?days per week) for 45 consecutive days. Body weight gain, reproductive organs weights, sperm characteristics, testosterone, and thiobarbutiric acid-reactive substances (TBARS) levels were investigated. The obtained results showed that ACMP decreased significantly (p?p?p?p?相似文献   
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