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91.
92.
BACKGROUND/AIMS: Epidemiological studies in humans link adult disease to abnormal growth in utero. In addition to general malnutrition of the foetus, preferential blood flow to the brain and heart may furthermore deprive organs such as the liver, spleen and kidneys of oxygen and macro- and micronutrients. As a consequence, these organs may not develop normally, which predisposes the individual to the so-called metabolic syndrome (syndrome X) in later life. The effects of foetal undernutrition on the growth of some abdominal organs were investigated by comparing the volume of the kidneys, spleen and liver in small-for-gestational-age (SGA) newborn infants with that in appropriate-for-gestational-age (AGA) newborn infants. METHODS: In 25 randomly selected AGA infants and 25 SGA infants, who were subdivided into three gestational age groups (<30, 30-36 and 37-40 wk) the volumes of the liver, kidneys and spleen were determined by ultrasonography. Organ volumes were estimated using the standard ellipsoid formula (longitudinal x anteroposterior x transverse diameter x pi/6). Liver/kidney, liver/spleen and kidney/spleen volume ratios were also determined. RESULTS: The volumes of the kidneys and liver differed significantly between AGA and SGA infants in all three gestational age groups (p < 0.0018 and p < 0.029, respectively). The fact that the spleen volume differed only in the 37-40 wk group (p = 0.0002) may indicate that there is a graded relationship across the whole range of normal birthweight. The correlation between the liver volume and birthweight differed significantly between SGA and AGA infants (r = 0.56 vs 0.84, p = 0.04). On the other hand, the volume ratios between the three organs were the same in all groups (p > 0.15). CONCLUSION: In intrauterine growth retarded infants, foetal growth of the liver and kidneys is more impaired than the body as a whole. Retarded foetal development of these organs may cause metabolic dysfunction, which predisposes to the group of diseases included in the so-called metabolic syndrome or syndrome X.  相似文献   
93.
The lack of selectivity of conventional antitumour drugs against cancer cells is responsible for their high toxicity. The development of new tumour-specific drugs is therefore highly needed. We tested the cytotoxic effects and the nature of cell death induced by a naturally dimeric bovine RNase and a newly engineered dimeric human RNase upon three genetically well-defined normal and malignant thyroid cell systems. RNases effects were compared with those of doxorubicin, a conventional antineoplastic drug. Our results show significant and selective proapoptotic effects exerted on tumour cells by both RNases, the strength of their cytotoxic and apoptotic activity being directly related to the degree of cell malignancy. No toxic effects were observed upon normal cells. Doxorubicin showed, instead, cytotoxic and apoptotic effects also against normal cells. The in vitro results were corroborated by the antitumour action of both dimeric RNases towards a malignant human thyroid tumour grown in nude mice. These results indicate a selective action of dimeric RNases against cancer cells and suggest the potential application of these molecules or their derivatives to the treatment of aggressive subtypes of thyroid cancer.  相似文献   
94.
BACKGROUND AND OBJECTIVES: Literature review suggests that the sentinel lymph node (sN) represents a reliable predictor of axillary lymph node status in breast cancer patients; however, some important issues, such as the optimisation of the technique for the intraoperative identification of the sN, the role of intraoperative frozen section examination of the sN, and the clinical implications of sN metastasis as regards the surgical management of the axilla, still require further confirmation. The authors aimed (1) to assess the feasibility of sN identification with a combined approach (vital blue dye lymphatic mapping and radioguided surgery, RGS) and the specific contribution of either techniques to the detection of the sN, (2) to determine the accuracy and usefulness of intraoperative frozen section examination of the sN in order to perform a one-stage surgical procedure, and (3) to define how the sN might modulate the therapeutic planning in different stages of disease. MATERIALS AND METHODS: From October 1997 to June 2001, 334 patients with early-stage (T(1-2) N(0) M(0)) invasive mammary carcinoma underwent sN biopsy; the average age of patients was 61.5 years (range, 39-75 years). In a subset of 153 patients, both vital blue dye (Patent Blue-V) lymphatic mapping and RGS were used to identify the sN, and the relative contribution of each of the two techniques was assessed. RESULTS: In the whole group, the sN was identified in 326 of 334 patients (97.6%), and 105 of 326 patients (37.3%) had positive axillary lymph nodes (pN+). In 9 of 105 pN+ patients, the definitive histologic examination of the sN did not show metastases but these were detected in non-sN, thus giving an 8.6% false-negative rate, a negative predictive value of 94.5% (156/165), and an accuracy of 96.5% (252/261). As regards the specific contribution of the two different techniques used in the identification of the sN, the detection rate was 73.8% (113/153) with Patent Blue-V alone, 94.1% (144/153) with RGS alone, and 98.7% (151/153) with Patent Blue-V combined with RGS (P < 0.001). Noteworthy, whenever the sN was identified, the prediction of axillary lymph node status was remarkably similar (93-95% sensitivity; 100% specificity; 95-97% negative predictive value, and 97-98% accuracy) whichever of the three procedures was adopted (Patent Blue-V alone, RGS alone, or combined Patent Blue-V and RGS). Intraoperative frozen section examination was performed in 261 patients, who had at least one sN identified, out of 267 patients who underwent complete axillary dissection; 170 patients had histologically negative sN (i.o. sN-) and 91 patients histologically positive sN (i.o. sN+). All 91 i.o. sN+ were confirmed by definitive histology, whereas in 14 of 170 i.o. sN- patients (8.2%) metastases were detected at definitive histology. As regards the correlation between the size of sN metastasis, the primary tumour size, and the status of non-sN in the axilla, micrometastases were detected at final histology in 23 patients and macrometastases in 82 patients. When only micrometastases were detected, the sN was the exclusive site of nodal metastasis in 20 of 23 patients (86.9%) while in 3 patients with tumour size larger than 10 mm micrometastases were detected also in non-sN. Macrometastases were never detected in pT(1a) breast cancer patients; the sN was the exclusive site of these metastases in 30 patients (36.6%), while in 52 patients (63.4%) there were metastases both in sN and non-sN. CONCLUSIONS: Sentinel lymphadenectomy can better be accomplished when both procedures (lymphatic mapping with vital blue dye and RGS) are used, because of the significantly higher sN detection rate, although the prediction of axillary lymph node status remains remarkably similar whichever method is used. The intraoperative frozen section examination proved to be rather accurate in predicting the actual pathologic status of the sN, with a negative predictive value of 91.8%; in 35% of patients it allowed sN biopsy and axillary dissection to be performed in a one-stage surgical procedure. Finally, specific clinical and histopathologic features of the primary tumour and sN might be used to tailor the loco-regional and systemic treatment in different clinical settings, such as in ductal carcinoma in-situ (DCIS), early-stage invasive breast cancer, and patients with large breast cancer undergoing neo-adjuvant CT for breast-saving surgery as well as elderly patients with operable breast cancer.  相似文献   
95.
Human thyroid papillary carcinomas are characterized by rearrangements of the RET protooncogene with a number of heterologous genes, which generate the RET/papillary thyroid carcinoma (PTC) oncogenes. One of the most frequent variants of these recombination events is the fusion of the intracellular kinase-encoding domain of RET to the first 101 amino acids of a gene named H4(D10S170). We have characterized the H4(D10S170) gene product, showing that it is a ubiquitously expressed 55 KDa nuclear and cytosolic protein that is phosphorylated following serum stimulation. This phosphorylation was found to depend on mitogen-activated protein kinase (MAPK) Erk1/2 activity and to be associated to the relocation of H4(D10S170) from the nucleus to the cytosol. Overexpression of the H4(D10S170) gene was able to induce apoptosis of thyroid follicular epithelial cells; conversely a carboxy-terminal truncated H4(D10S170) mutant H4(1-101), corresponding to the portion included in the RET/PTC1 oncoprotein, behaved as dominant negative on the proapoptotic function and nuclear localization of H4(D10S170). Furthermore, conditional expression of the H4(D10S170)-dominant negative truncated mutant protected cells from stress-induced apoptosis. The substitution of serine 244 with alanine abrogated the apoptotic function of H4(D10S170). These data suggest that loss of the H4(D10S170) gene function might have a role in thyroid carcinogenesis by impairing apoptosis.  相似文献   
96.
Rationale and objective Depression is a significant complication of stroke. The effectiveness of antidepressant drugs in the management of post-stroke depression (PSD) has been widely investigated. However, the choice of antidepressant drug is critically influenced by its safety and tolerability and by its effect on concurrent pathologies. Here we investigate the efficacy and safety of a selective serotonin reuptake inhibitor (SSRI), citalopram, and a noradrenaline reuptake inhibitor (NARI), reboxetine, in post-stroke patients affected by anxious depression or retarded depression.Methods This was a randomized double-blind study. Seventy-four post-stroke depressed patients were diagnosed as affected by anxious or retarded depression by using a synoptic table. Randomisation was planned so that 50% of the patients in each subgroup were assigned for 16 weeks to treatment with citalopram and the remaining 50% were assigned to treatment with reboxetine. The Beck Depression Inventory (BDI), the Hamilton Depression Rating Scale (HDRS) and a synoptic table were used to score depressive symptoms.Results Both citalopram and reboxetine showed good safety and tolerability. Citalopram exhibited greater efficacy in anxious depressed patients, while reboxetine was more effective in retarded depressed patients.Conclusions Citalopram or other SSRIs and reboxetine may be of first choice treatment in PSD because of their good efficacy and lack of severe side effects. In addition, PSD patients should be classified according to their clinical profile (similarly to patients affected by primary depression) for the selection of SSRIs or reboxetine as drugs of choice in particular subgroups of patients.  相似文献   
97.
98.
OBJECTIVE: The present study was undertaken to evaluate the possible occurrence of immunological abnormalities in thalassaemia major patients treated with deferiprone (L1). METHODS: Longitudinal observational cohort study. RESULTS: The absolute number of CD8+ lymphocytes was high and the CD4/CD8 ratio low before L1 treatment; these parameters returned to normal after 3 months of L1 treatment. TNF-alpha, IL-2 and IL-2sRalpha were elevated before L1 treatment (11.83 +/- 1.75, 11.75 +/- 3.91, 1,409 +/- 621 pg/ml, respectively), while IL-6 was normal (2.58 +/- 0.79 pg/ml). After 12 months of treatment, IL-10 was higher than in previous periods, although always within the normal range. TNF-alpha, IL-2 and IL-2sRalpha returned to normal after 12, 6, and 3 months of L1 treatment, respectively.  相似文献   
99.
BACKGROUND: The incidence of deep vein thrombosis and pulmonary embolism following laparoscopic surgery is unknown and studies on alterations of hemostasis after laparoscopy are inconclusive. METHODS: In this study we prospectively evaluated changes in prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen (Fg), antithrombin III (ATIII), prothrombin fragment F 1 + 2, beta-thromboglobulin (betaTG) and D-dimer (D-D), preoperatively and 24 h after laparoscopic surgery in 16 patients. RESULTS: Comparing pre- and postoperative values, no statistical differences were observed in aPTT, F1 + 2, and ATIII measurements. Postoperative PT values increased slightly (p approximately 0.05) after surgery. Conversely, Fg, betaTG, and D-D values were statistically higher in the 24-h evaluation (p = 0.008, 0.01, and 0.045, respectively). CONCLUSIONS: These data suggest that laparoscopic surgery induces activation of coagulation and fibrinolytic pathways and, additionaly, betaTG elevation, which has never been reported and might account for postoperative platelet activation and a greater risk of thrombogenicity. Therefore, routine thromboembolic prophylaxis in patients undergoing laparoscopic surgery is recommended.  相似文献   
100.
Di-(2-ethylhexyl)phthalate (DEHP), the most commonly used plasticizer in flexible polyvinylchloride formulations, is a ubiquitous environmental contaminant. To date, no information exists on the potential health hazards from exposure to DEHP and/or its main metabolite, mono-(2-ethylhexyl)phthalate (MEHP), in high-risk conditions, such as pregnancy and during the neonatal period. The aim of this study was to evaluate prenatal exposure to DEHP and/or MEHP and its possible biologic effects. We measured serum DEHP and MEHP concentrations in the cord blood of 84 consecutive newborns by high-performance liquid chromatography. Relationships between DEHP/MEHP and infant characteristics were tested using Fisher's exact test, unpaired t-tests, and univariate linear regression analyses, and significant differences on univariate analysis were evaluated using multiple logistic regression analysis. We found detectable cord blood DEHP and/or MEHP concentrations in 88.1% of the samples. Either DEHP or MEHP was present in 65 of 84 (77.4%) of the examined samples. Mean concentrations of DEHP and MEHP were 1.19 +/- 1.15 microg/mL [95% confidence interval (CI), 0.93-1.44, range = 0-4.71] and 0.52 +/- 0.61 microg/mL (95% CI, 0.39-0.66, range = 0-2.94), respectively. MEHP-positive newborns showed a significantly lower gestational age compared with MEHP-negative infants (p = 0.033). Logistic regression analysis results indicated a positive correlation between absence of MEHP in cord blood and gestational age at delivery (odds ratio = 1.50, 95% CI, 1.013-2.21; p = 0.043). These findings confirm that human exposure to DEHP can begin in utero and suggest that phthalate exposure is significantly associated with a shorter pregnancy duration.  相似文献   
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