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11.
Methylenetetrahydrofolate reductase (MTHFR) polymorphisms have been associated not only with the risk for acute lymphoblastic leukemia (ALL) in adults and children, but also with increased methotrexate toxicity. The present study aimed to investigate whether MTHFR polymorphisms modify the risk for development of secondary malignancies in children treated for ALL with protocols that included high-dose methotrexate. MTHFR genotypes were determined in DNA samples isolated from archived bone marrow smears of 15 patients with a second malignancy and a matched control group of 30 patients who did not developed a second malignancy after the treatment for ALL. The frequencies of MTHFR C677T and A1298C genotypes in all patients were: C677T: CC 40%, CT 46.7% and TT 13.3% and A1298C: AA 46.7%, AC 44.4% and CC 8.9%. The relative risk for second malignancy was not significantly increased in ALL patients having at least one polymorphic C667T [odds ratio (OR) 1.51; 95% confidence interval (CI) 0.43 - 5.31] or one polymorphic A1298C allele (OR 1; 95% CI 0.29 - 3.46). Our study suggests that MTHFR polymorphisms are not associated with increased risk of second cancer in children treated with high-dose methotrexate.  相似文献   
12.
Purpose:To determine the retinal nerve fiber layer (RNFL) thickness and ganglion cell complex (GCC) thickness in patients having relative afferent pupillary defect (RAPD) measured by optical coherence tomography (OCT).Methods:This cross-sectional study was conducted on 30 patients with posterior segment disease and glaucoma presenting with RAPD. The control group comprised 30 patients with the aforementioned diseases without RAPD. RAPD was graded using neutral density filters placed over the unaffected eye. Peripapillary RNFL thickness and macular GCC were measured using the Cirrus HD-OCT machine.Results:There were 45 males and 15 females. There was a statistically significant (P < 0.05) difference in the mean of average RNFL thickness in patients having RAPD (64.73 ± 15.16 mm in the affected eyes) as compared to sick control (82.73 ± 11.33 mm in the affected eyes). It was further observed that there was a decrease in RNFL thickness with advancing grades of RAPD. There was a statistically significant (P < 0.05) difference in the mean of average GCC thickness in patients having RAPD (51.57 ± 14.96 mm in the affected eyes) as compared to sick control (76.36 ± 8.06 mm in the affected eyes).Conclusion:Our study suggests that there is a significant reduction in RNFL thickness and GCC thickness in RAPD patients as compared to the sick control group.  相似文献   
13.
ObjectivesObstructive sleep apnea (OSA) is a common condition closely related to obesity, insulin resistance, dyslipidemia, and cardiovascular disease. The aim of this study was to explore the possible relationship between OSA and proprotein convertase subtilisin/kexin type 9 (PCSK9).MethodsFull-night polysomnography was performed on 150 participants who were divided into three groups: controls, OSA patients on statin therapy, and OSA patients not on statin therapy. Biochemical markers, plasma low-density lipoprotein (LDL) and high-density lipoprotein (HDL) subclasses, and PCSK9 were determined.ResultsPCSK9 was highest in OSA patients on statins compared to the control group and to OSA patients not on statins (p = 0.036 and p = 0.039, respectively), after adjustment for body mass index (BMI). LDL diameter was greater in OSA patients not on statins compared to OSA patients on statins (p = 0.032). PCSK9 was highest in the group of patients with all three risk factors (diagnosed OSA, statins, BMI ≥25 kg/m<sup>2</sup>) compared to groups with no, one, and two risk factors (p = 0.031, p = 0.001, and p = 0.029, respectively). Presence of OSA, statin therapy, and BMI ≥25 kg/m<sup>2</sup> when combined were independently associated with higher levels of PCSK9 when adjusted for antihypertensive therapy, small dense LDL, and HDL 3c subclass (odds ratio = 2.849; interquartile range [1.026–7.912], p = 0.044).ConclusionStatin therapy was closely related to PCSK9. OSA along with obesity and statin use induces elevation of PCSK9.  相似文献   
14.
Human intervention studies have suggested an exciting synergistic action between calcium supplementation and aspirin intake in reducing the risk of colorectal cancer. The aim of this study was to determine whether such a synergy can be demonstrated on azoxymethane (AOM)-induced colon aberrant crypt foci (ACF) formation in mice and rats. Female CF-1 mice and male F344 rats were injected subcutaneously with AOM and then received diet treatments for 8 wk. The basal control diet contained high fat (20% mixed lipids by weight) and low calcium (1.4 mg/g diet) to mimic the average Western diet. The treatment diets contained enriched calcium (5.2 mg calcium/g diet), aspirin (0.2 mg aspirin/g diet), or calcium plus aspirin (5.2 mg calcium plus 0.2 mg aspirin/g diet). Treatment with calcium, aspirin, or their combination significantly decreased the number of total ACF and aberrant crypt per mouse (by 43–59%) or rat (by 23–38%), but statistically significant differences among the 3 groups were not observed. A hint of additivity between calcium and aspirin was observed in mice but not in rats. These results indicate that the combination of calcium and aspirin did not produce a synergistic effect on the ACF formation in AOM-treated mice and rats.  相似文献   
15.
High plasma HDL-cholesterol (HDL-c) is a well-established protective factor in coronary artery disease (CAD). One of its potential protective mechanisms is the inhibition of the cytokine-induced upregulation of expression of cellular adhesion molecules (CAMs). High sCAM levels were found to be associated with low HDL-c in some studies performed mostly in hyperlipidemic subjects, but this association has not yet been investigated in CAD patients. In addition, conflicting results were obtained from in vitro studies that explored the proposed HDL effect on cytokine-induced CAM expression. The aim of the present case-control study was to investigate whether low HDL-c values are associated with CAM overexpression in normolipidemic CAD patients and healthy individuals, matched according to age and gender. Plasma HDL-c, sICAM-1, sVCAM-1, and sE-selectin were measured in 37 normolipidemic patients with angiographically verified coronary artery disease and in 52 healthy normolipidemic subjects. The sCAM values obtained in the subjects (patients or controls) with low HDL-c levels (< 1.03 mmol/L) were compared with the values in the subjects with high HDL-c (>or= 1.03 mmol/L). No significant difference was found between sICAM-1, sVCAM-1, and E-selectin values obtained in subjects with low and high HDL-c, either among the patients or the healthy controls. In conclusion, low HDL-c levels are not associated with CAM overexpression in normolipidemic CAD patients and healthy subjects.  相似文献   
16.
CTLA-4 exon 1 polymorphism in patients with autoimmune blood disorders   总被引:6,自引:0,他引:6  
CTLA-4 is a CD28 homologue that plays an important role in negative regulation of T-cell responses. Its transient expression on the surface of activated T cells antagonizes the activating signals and terminates the T-cell response. An A to G polymorphism at position 49 of the CTLA-4 first exon has recently been associated with several autoimmune disorders. In the present study we have examined the prevalence of the A and G alleles of the CTLA-4 gene in 50 patients with autoimmune hemolytic anemia (AIHA), of which 20 had idiopathic AIHA and 30 had AIHA and chronic lymphocytic leukemia (CLL), and in 60 patients with immune thrombocytopenic purpura (ITP). Control subjects were 100 healthy individuals and 100 CLL patients without clinical evidence for an autoimmune disease. The G allele was present at a significantly higher frequency among the patients with AIHA (P = 0.003), whereas no difference was observed between patients with ITP and controls. The G allele frequency was highest among CLL patients who had developed AIHA. The obtained data indicate that the G allele of CTLA-4 predisposes to the development of AIHA, particularly among patients with CLL.  相似文献   
17.
The main steps in the management of differentiated thyroid cancer are thyroidectomy, treatment with iodine-131 ((131)I), and follow-up with whole-body scanning (WBS) and serum thyroglobulin (Tg) determination. Both (131)I treatment and follow-up require maximum stimulation of normal or pathological thyroid remnants by TSH. The use of recombinant human TSH (rhTSH) has been shown to be useful for follow-up, whereas previous reports are not univocal regarding the use of (131)I postsurgical ablation of thyroid remnants, at least when low doses (30 mCi) of (131)I are administered. A possible explanation for the diminished effectiveness of (131)I treatment after rhTSH may be the interference of iodine content of L-thyroxine (L-T4) therapy during the protocol of administration of rhTSH. We have evaluated the effectiveness of stimulation by rhTSH for radioiodine ablation of postsurgical remnants, stopping L-T4 the day before the first injection of rhTSH and restarting L-T4 the day after (131)I. The study included two groups of patients: group 1 included 16 patients with differentiated thyroid cancer (15 papillary cancers and 1 follicular cancer, stages I and II), who were treated with 30 mCi (131)I with the aid of rhTSH, using the standard protocol but stopping L-T4 as stated previously; and group 2 included 24 patients with the same features (histology and stage) of disease treated with 30 mCi in the hypothyroid state after L-T4 withdrawal. In both groups, serum TSH reached a very good stimulation level [76-210 U/liter (mean, 112 +/- 11 SE) and 38-82 U/liter (mean, 51 +/- 3 SE), respectively]. At the first WBS (after (131)I treatment), all patients showed thyroid remnants. Furthermore, two patients of the first group and three patients of the second group showed lymph node metastases. After 1 yr, all patients were studied again and underwent WBS with a tracer dose of (131)I and serum Tg measurement using rhTSH with the same protocol in both groups. The percentage of ablation (undetectable Tg and a negative WBS) was higher, although not reaching statistical significance, in patients treated with rhTSH: 81.2% in patients treated by rhTSH withdrawal and 75.0% in patients treated by L-T4 withdrawal, respectively. No patient experienced symptoms of hypothyroidism during the 4 d of L-T4 interruption, and serum T4 remained in the normal range. Urinary iodine was analyzed in both groups and compared with a control group of patients who received, for diagnostic purposes, rhTSH without stopping L-T4. In the first group, urinary iodine was 47.2 +/- 4.0 microg/liter (mean +/- SE; P = 0.21 vs. the second group, P = 0.019 vs. control group). In the second group, urinary iodine was 38.6 +/- 4.0 microg/liter (mean +/- SE; P < 0.001 vs. control group); urinary iodine in the control group was 76.4 +/- 9.3 microg/liter (mean +/- SE). Our data show that rhTSH, as administered in the protocol stated previously, allows at least the same rate of ablation of thyroid remnants when low doses (30 mCi) of (131)I are used. The possible role of interference of iodine content in L-T4 is not surprising if we consider that the amount of iodine in 30 mCi is negligible (5 microg) compared with the amount of iodine content in a daily dose of T(4) ( approximately 50 microg). The cost of rhTSH seems modest compared with the high cost of complex therapeutic regimens in other areas of oncology and in consideration of the well-being of patients and of the high level of effectiveness of the treatment.  相似文献   
18.
19.
Pseudomonas aeruginosa san ai is a promising candidate for bioremediation of cadmium pollution, as it resists a high concentration of up to 7.2 mM of cadmium. Leaving biomass of P. aeruginosa san ai exposed to cadmium has a large biosorption potential, implying its capacity to extract heavy metal from contaminated medium. In the present study, we investigated tolerance and accumulation of cadmium on protein level by shotgun proteomics approach based on liquid chromatography and tandem mass spectrometry coupled with bioinformatics to identify proteins. Size exclusion chromatography was used for protein prefractionation to preserve native forms of metalloproteins and protein complexes. Using this approach a total of 60 proteins were observed as up-regulated in cadmium-amended culture. Almost a third of the total numbers of up-regulated were metalloproteins. Particularly interesting are denitrification proteins which are over expressed but not active, suggesting their protective role in conditions of heavy metal exposure. P. aeruginosa san ai developed a complex mechanism to adapt to cadmium, based on: extracellular biosorption, bioaccumulation, the formation of biofilm, controlled siderophore production, enhanced respiration and modified protein profile. An increased abundance of proteins involved in: cell energy metabolism, including denitrification proteins; amino acid metabolism; cell motility and posttranslational modifications, primarily based on thiol-disulfide exchange, were observed. Enhanced oxygen consumption of biomass in cadmium-amended culture versus control was found. Our results signify that P. aeruginosa san ai is naturally well equipped to overcome and survive high doses of cadmium and, as such, has a great potential for application in bioremediation of cadmium polluted sites.

When exposed to cadmium a highly resistant strain P. aeruginosa san ai responds by an increased metalloprotein expression (particularly denitrification proteins), an enhanced respiration, and a pronounced thiol-disulfide protein modifications.  相似文献   
20.
OBJECTIVE: Tumour size represents a much-debated prognostic factor in papillary cancer, and the necessity to perform a fine-needle aspiration (FNA) on small nodules is a frequent matter of discussion. We compared some prognostic histological features for various sizes of papillary cancers (PCs) and, with regard to these prognostic features, we compared non-incidental with incidental PCs. We also considered the possibility that ultrasonography could detect nodules harbouring the most aggressive cancers. DESIGN AND PATIENTS: We have studied patients with a histological diagnosis of PC from 1999 to 2003. FNA was performed on all nodules > 1.0 cm and on hypoechoic nodules with irregular margins or microcalcification when the size was < 1.0 cm (3321 FNAs in total). We were able to consider several different types of patients: those with PC diagnosed by FNA before surgery; those with large goitre and PC of small size diagnosed after histological examination and in whom a careful examination of the presurgical ultrasonography could show a distinct highly suspicious nodule that was not subjected to FNA, and patients with real incidental PC (that is, those with nodular goitre who correctly underwent FNA on suspicious nodules but in whom thyroid cancer was discovered only at histological examination). We considered two groups of patients with PC. Group 1 PCs were diagnosed before surgery with FNA (128 cases); in this group we also considered the two cases that were not correctly diagnosed before surgery. Group 2 real incidental PCs (12 cases) were found in goitres at histological examination after thyroidectomy for goitre (282 thyroidectomies). Group 1 was divided into three subgroups according to the maximum size of the PC at histological examination: (a) 44 PCs with maximum size < 10 mm, (b) 47 PCs with maximum size between 10 mm and 20 mm, and (c) 39 PCs with maximum size 20 mm. In all subgroups 1 as well as in group 2, the following four histological features were considered separately: multifocality, extracapsular extension, lymph-node involvement and its extent, and special aggressive features (dedifferentiation and/or insular aspects, tall and columnar variants). RESULTS: In subgroups 1a, 1b and 1c the results were, respectively: multifocality 56.8, 57.4 and 51.2%; extracapsular extension 27.2, 23.4 and 46.3% (P = 0.01, subgroups 1a and 1b vs. subgroup 1c); lymph-node metastasis 13.5, 23.3 and 46.1% (P = 0.003 subgroup 1a vs. 1c; P = 0.04, subgroup 1b vs. 1c); special aggressive features 11.3, 25.5 and 28.2% (P = ns). Group 2 showed one case of multifocality (8.3%) in a patient with prior exposure to radiotherapy in childhood, while no case was found of extracapsular invasion or lymph-node involvement, and only one patient had a PC with features of dedifferentiation. CONCLUSIONS: Non-incidental cancer, apart from multifocality, showed a classical progression for all prognostic factors from microcarcinoma to larger cancers. However, real incidental PC seemed to be different from non-incidental PC microcarcinoma regarding the main prognostic features. We conclude that ultrasonography is useful not only in terms of revealing the presence of cancer but also in identifying the most aggressive cancers.  相似文献   
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