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61.
62.
Aflatoxin B1 (AFB1) is a potent mycotoxin and natural carcinogen. The primary producers of AFB1 are Aspergillus flavus and A. parasiticus. Sterigmatocystin (STC), another mycotoxin, shares its biosynthetic pathway with aflatoxins. While there are abundant data on the biological effects of AFB1, STC is not well characterised. According to published data, AFB1 is more harmful to biological systems than STC. It has been suggested that STC is about one-tenth as potent a mutagen as AFB1 as measured by the Ames test. In this research, the biological effects of S9 rat liver homogenate-activated and non-activated STC and AFB1 were compared using two different biomonitoring systems, SOS-Chromotest and a recently developed microinjection zebrafish embryo method. When comparing the treatments, activated STC caused the highest mortality and number of DNA strand breaks across all injected volumes. Based on the E. coli SOS-Chromotest, the two toxins exerted the same genotoxicities. Moreover, according to the newly developed zebrafish microinjection method, STC appeared more toxic than AFB1. The scarce information correlating AFB1 and STC toxicity suggests that AFB1 is a more potent genotoxin than STC. Our findings contradict this assumption and illustrate the need for more complex biomonitoring systems for mycotoxin risk assessment.  相似文献   
63.
ABSTRACT

The growing number of older adults places insurmountable load on family members and professional caregivers. Assistive technology with the aid of robots can present a possible solution. The goal of this article was to test a companion robot supporting older adults in their home environments. Eight senior volunteers were involved in the field test. They all lived alone and were self-supporting. The robot was capable of providing cognitive assistance to manage the user’s daily routine. Each participant used the robot for 94.9 ± 19.6 days. The primary communication modality was voice communication in their natural language, while the touch screen display was also available for interaction with the robot. The assistance given in daily living was evaluated by subjective (the user’s opinion) and objective (logged data) criteria. The most useful and the least reliable robot functions according to the users were the navigation and the verbal communication. Entertainment, locomotion, and weather forecast were the most frequently used functions, while the shopping list was the least popular. The companion robot used in the test was accepted enthusiastically by the senior subjects. Specific robot functions (mainly navigation in the apartment and the speech recognition) require improvement to better accommodate real circumstances.  相似文献   
64.
The possible pathogenic role of triglycerides (TG) in the development of ischemic stroke is still under extensive investigation. Recently, apolipoprotein (apo)A5 gene promoter region T-1131C polymorphism has been shown to associate with elevated serum TG levels. In the current work, a total of 302 subjects were classified as being large vessel-associated, small vessel-associated, or belonging to a mixed group of ischemic stroke-affected patients. The level of TG was increased in all groups (p<0.01). The apoA5-1131C allele frequency was approximately twofold in all groups of stroke patients compared with the controls (5 vs 10–12%; p<0.05); and the apoA5-1131C allele itself was also found to associate with increased TG levels in all groups. In a multivariate logistic regression analysis model adjusted for differences in age, gender, serum cholesterol, hypertension, pressence of diabetes mellitus, smoking and drinking habits, and ischemic heart disease, a significantly increased risk of developing stroke disease was found in patients carrying the apoA5-1131C allele (p<0.05; odds ratio OR=2.1 [1.3–4.7]); this association was also proven for all subtypes of the stroke. The results presented here suggest that the apoA5-1131C allele is an independent risk factor for the development of stroke. Being that apoA5 gene is under the control of the peroxisome proliferator-activated receptor α, theoretically, the current observations also can have long-term therapeutic consequences.  相似文献   
65.
The spectrum of serological markers associated with inflammatory bowel disease(IBD)is rapidly growing.Due to frequently delayed or missed diagnoses,the application of non-invasive diagnostic tests for IBD,as well as differentiation between ulcerative colitis(UC)and Crohn’s disease(CD),would be useful in the pediatric population.In addition,the combination of pancreatic autoantibodies and antibodies against Saccharomyces cerevisiae antibodies/perinuclear cytoplasmic antibody(pANCA)improved the sensitivity of serological markers in pediatric patients with CD and UC.Some studies suggested that age-associated differences in the patterns of antibodies may be present,particularly in the youngest children.In CD,most patients develop stricturing or perforating complications,and a significant numberof patients undergo surgery during the disease course.Based on recent knowledge,serum antibodies are qualitatively and quantitatively associated with complicated CD behavior and CD-related surgery.Pediatric UC is characterized by extensive colitis and a high rate of colectomy.In patients with UC,high levels of antiCBir1 and pANCA are associated with the development of pouchitis after ileal pouch-anal anastomosis.Thus,serologic markers for IBD can be applied to stratify IBD patients into more homogeneous subgroups with respect to disease progression.In conclusion,identification of patients at an increased risk of rapid disease progression is of great interest,as the application of early and more aggressive pharmaceutical intervention could have the potential to alter the natural history of IBD,and reduce complications and hospitalizations.  相似文献   
66.
Immunization with chondroitinase ABC–digested fetal human cartilage proteoglycan and Freund's complete adjuvant induced polyarthritis and ankylosing spondylitis in female BALB/c mice. The initial external symptoms of the joint inflammation were swelling and redness. This was associated with edema of the synovium and periarticular tissues and gross proliferation of cells, which reached a peak during weeks 7–9 of the experiment. Mononuclear cell infiltration, with perivascular concentration and occlusion of small vessels, was common. Synovitis increased in severity, villous pannus developed, and erosions of bone, articular cartilage, and occasionally, growth plate were observed. The lumbar spine and the proximal intervertebral discs of the tail also exhibited inflammatory and degenerative changes. As the arthritis progressed, sometimes with acute inflammatory exacerbations, more joints became involved and, by the sixteenth to the twentieth weeks of the experiment, a progressive polyarthritis, with gross joint deformities and restricted function, developed in the majority of the limb joints. Clinical and morphologic features of the disease correlated well with radiologic analysis and with an increased deposition of 99mTc–methylene diphosphonate (determined by radionuclide imaging). The development of this arthritis was accompanied by the expression of cell-mediated and humoral immunity to the immunizing antigen. However, this immunity was also observed, although it was generally less well developed, in mice that received the intact or digested proteoglycan without adjuvant. These mice did not usually develop arthritis. Control mice that received only adjuvant did not develop arthritis.  相似文献   
67.
In the treatment of gastric cancer R0 surgical resection is the only hope for cure. Unfortunately most patients are first seen when they are in an advanced stage, when the possibility of R0 resection is very poor. In these cases administration of other therapies is justified. In the last decade neoadjuvant combination chemotherapy had been introduced with promising results. ECF neoadjuvant chemotherapy has 60% response rate in irresectable cases. We report about a patient with locally advanced gastric cancer treated with neoadjuvant ECF chemotherapy. The patient reacted with complete response, so following chemotherapy R0 resection could be carried out. We describe different therapies used for patients with locally advanced gastric cancer. Neoadjuvant chemotherapy is a recommended therapeutic modality in locally advanced gastric cancer, because it may have the effect of irresectable disease becoming resectable.  相似文献   
68.
ABSTRACT: BACKGROUND: Severe renal manifestation of systemic lupus erythematosus (SLE) is not uncommon and is associated with an indeterminate prognosis. Complete remission can be obtained, however, at least in the young when chronic lesions are absent and adequate anti-inflammatory therapy is immediately initiated. CASE PRESENTATION: We report the unusual case of a 12-year-old girl who presented with severe oliguric renal failure, macrohematuria and skin rash. Renal biopsy revealed the diagnosis of severe diffuse proliferative glomerulonephritis (GN) with cellular crescents in 15 out of 18 glomeruli and full-house pattern in immunofluorescence indicating lupus nephritis IVB according to WHO, IV-G(A) according to ISN/RPS classification. The serological parameters confirmed the diagnosis of (SLE and the patient was immediately treated with methylprednisolone, cyclophoshamide and immunoadsorption. Initially, despite rapid amelioration of her general condition, no substantial improvement of renal function could be achieved and the patient needed hemodialysis treatment for 12 weeks. Unexpectedly, in the further follow-up at first diuresis increased and thereafter also creatinine levels substantially declined so that hemodialysis could be discontinued. Today, 6 years after the initial presentation, the patient has normal renal function and a SLEDAI score of 0 under a continous immunosuppressive therapy with Mycophenolate mofetil (MMF). CONCLUSION: Despite the severity of the initial renal injury and the unfavourable renal prognosis the kidney apparentlyhas a tremendous capacity to recover in young patients when the damage is acute and adequate anti-inflammatory therapy is initiated without delay.  相似文献   
69.
Central nervous and hematopoietic systems share developmental features. We report that thrombopoietin (TPO), a stimulator of platelet formation, acts in the brain as a counterpart of erythropoietin (EPO), a hematopoietic growth factor with neuroprotective properties. TPO is most prominent in postnatal brain, whereas EPO is abundant in embryonic brain and decreases postnatally. Upon hypoxia, EPO and its receptor are rapidly reexpressed, whereas neuronal TPO and its receptor are down-regulated. Unexpectedly, TPO is strongly proapoptotic in the brain, causing death of newly generated neurons through the Ras-extracellular signal-regulated kinase 1/2 pathway. This effect is not only inhibited by EPO but also by neurotrophins. We suggest that the proapoptotic function of TPO helps to select for neurons that have acquired target-derived neurotrophic support.  相似文献   
70.
BACKGROUND: Williams-Beuren syndrome is a multisystem developmental disorder caused by a microdeletion at chromosome 7q11.23. In its classic form it includes dysmorphic facial features, joint contractures, retardation of growth and mental development, gregarious personality, visuospatial cognitive deficits, hypercalcemia, primary or secondary hypertension and cardiovascular disorders. AIM: Clinical diagnosis of Williams-Beuren syndrome can be a challenge in young patients if none of the characteristic cardiovascular features, i.e. supravalvular aortic stenosis or pulmonary artery stenosis, are present. Our aim was to demonstrate the changes in cardiovascular lesions during the postnatal development of Williams-Beuren patients and to follow all cardiovascular findings beyond the most common ones. METHODS: The cardiovascular status of 29 patients with Williams-Beuren syndrome (mean age 12.8 years) was recorded in correlation with age. RESULTS: Cardiovascular diagnoses changed in the majority (72.4%) of patients. Interestingly, 44.8% of the patients had periods with no reported cardiovascular disease. Furthermore, 65.5% of the patients experienced periods when none of the typical cardiovascular lesions, i.e. diffuse or localized supravalvular aortic stenosis and/or pulmonary artery stenosis, were detected. Spontaneous regression and progression of both supravalvular aortic stenosis and pulmonary artery stenosis were observed. An unexpectedly high frequency (41%) of mitral valve disorders was found. CONCLUSIONS: Our study showed that temporary absence of and changes in cardiovascular findings are frequent in Williams-Beuren syndrome. These results could contribute to the refinement of diagnostic criteria and recommendations for cardiovascular follow-up of patients with this syndrome.  相似文献   
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