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31.
Exhaled breath condensate: a new method for lung disease diagnosis.   总被引:1,自引:0,他引:1  
Analysis of exhaled breath composition in lung disease patients can indirectly point to biochemical changes that occur in the fluid lining airway surfaces. The parameters of redox and acid-base changes, and of inflammatory changes relevant in the pathogenesis of most pulmonary diseases are currently most widely determined in exhaled breath condensate. The collection of exhaled breath condensate is a safe, non-invasive, easy and simple diagnostic procedure that is suitable for longitudinal studies and applicable in patients of all age groups, irrespective of the disease severity. In spite of many scientific studies involving lung disease patients, methodology for exhaled breath condensate collection and analysis has not yet been realized for daily utilization. Additional studies of the exact origin of condensate constituents and standardization of the overall analytical process, including collection, storage, analysis and result interpretation, are needed. Irrespective of these limitations, further investigation of this sample type is fully justified by the fact that classical specimens used in the management of pulmonary disease are either obtained by invasive procedures (e.g., induced sputum, biopsy, bronchoalveolar lavage) or cannot provide appropriate information (e.g., urine, serum). Analysis of exhaled breath condensate in the future might contribute significantly to our understanding of the physiological and pathophysiological processes in lungs, to early detection, diagnosis and follow up of disease progression, and to evaluation of therapeutic response.  相似文献   
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BACKGROUND: The aim of the present work was to characterize the molecular defects of a slow-migrating (albumin Zagreb) and a fast-migrating (albumin Krapina) genetic variant of human serum albumin detected in heterozygous persons living in Croatia and to elucidate the fatty acid-binding properties of the two alloalbumins. METHODS: Purification and structural identification of the variants were performed by conventional protein chemistry methods, whereas types and amounts of albumin-bound, endogenous fatty acids were determined by gas chromatography. RESULTS: Protein sequencing established that albumin Zagreb is a proalbumin variant (-1Arg-->Gln), and that albumin Krapina is due to a mutation within the mature polypeptide chain (573Lys-->Glu). The gas chromatographic results showed that the fatty acid-binding properties of the proalbumin variant are normal, while the amino acid substitution in position 573 resulted in a general decrease of fatty acid binding. CONCLUSIONS: The structural defects of the first alloalbumins, detected by routine clinical electrophoresis among the Croatian population, were characterized. Albumin Zagreb is caused by a hot-spot mutation occurring in a CpG sequence in the albumin gene. It is commonly assumed that bisalbuminaemia has no direct clinical relevance. However, the present study suggests that naturally occurring mutations can affect the ligand-binding properties of human serum albumin.  相似文献   
34.
The widespread use of antineoplastic drugs in cancer treatment increased concern about possible hazard to workers involved in the preparation and administration of these drugs. In the present study, the effects of commercial antioxidative drug Oligogal Se® on genome protection were analyzed in 15 nurses handling the antineoplastic drugs at the Oncology Department in comparison to twenty healthy volunteers. The nurses took antioxidant mixture Oligogal Se®, consisting of vitamins C, E, A and selenium, one capsule per day, over a period of 6 months. Genome damage was measured in peripheral blood lymphocytes by usage of sister chromatid exchange test and the cytokinesis-block micronuclei test. The frequency of sister chromatid exchange (SCE) and micronuclei (MN) in the exposed group was significantly higher when compared to the control group (SCE, p < 0.05; MN, p < 0.01 respectively). After antioxidant supplementation, the frequency of sister chromatid exchange and micronuclei decreased (p < 0.05) when compared with the values from the beginning of the study, but were still above the values of the control group. The effects of confounding factors such as cigarette smoking and cytostatics exposure time were also evaluated. The data indicated that Oligogal Se® contributed to the decreasing of genome damages in workers handling the cytostatics.  相似文献   
35.
We investigated the potential of Nicotiana benthamiana to express the E7 protein of human papillomavirus 8 (HPV-8), a paradigm genotype among cutaneous HPVs. The protein, modified in its putative pRb-binding domain (E7(QGD)), was transiently expressed in leaves following infiltration with agrobacteria carrying either a binary vector combined with silencing suppressor constructs or replicating tobacco mosaic virus (TMV)-based vectors with different targeting signals. HPV-8 E7(QGD) yields ranged from 250?ng to 4.6?mg per gram of fresh leaf tissue. The highest yields were obtained with TMV-based vectors targeting the antigen to the apoplast. HPV8-CER (H2(q)) mice transformed with the complete early region of HPV-8 showed a delay in the onset of skin papillomatous lesions and produced E7-specific immunoglobulins G when inoculated subcutaneously with leaf extracts expressing E7(QGD). Furthermore, we demonstrated that the plant-made HPV-8 E7(QGD) induced a specific cytotoxic response in C57BL/6 (H2(b)) mice.  相似文献   
36.
Mannose-binding lectin (MBL) is a serum lectin that plays a significant role in innate host defence. Individuals with mutations in exon 1 of the MBL2 gene have reduced MBL ligand binding and complement activation function and increased incidence of infection. We proposed that, during infection, MBL deficiency may impact on dendritic cell (DC) function. We analysed the blood myeloid DC (MDC) surface phenotype, inflammatory cytokine production and antigen-presenting capacity in MBL-deficient (MBL-D) individuals and MBL-sufficient (MBL-S) individuals using whole blood culture supplemented with zymosan (Zy) or MBL-opsonized zymosan (MBL-Zy) as a model of infection. Zy-stimulated MDCs from MBL-D individuals had significantly increased production of interleukin (IL)-6 and tumour necrosis factor (TNF)-α. Stimulation with MBL-Zy significantly decreased IL-6 production by MDCs from MBL-D, but had no effect on TNF-α production. MDCs from both MBL-S and MBL-D individuals up-regulated expression of the activation molecule CD83, and down-regulated expression of homing (CXCR4), adhesion (CD62L, CD49d) and costimulatory (CD40, CD86) molecules in response to Zy and MBL-Zy. MDC from both MBL-D and MBL-S individuals induced proliferation of allogeneic (allo) T cells following Zy or MBL-Zy stimulation; however, MBL-D individuals demonstrated a reduced capacity to induce effector allo-T cells. These data indicate that MBL deficiency is associated with unique functional characteristics of pathogen-stimulated blood MDCs manifested by increased production of IL-6, combined with a poor capacity to induce effector allo-T-cell responses. In MBL-D individuals, these functional features of blood MDCs may influence their ability to mount an immune response.  相似文献   
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Folate is a water-soluble vitamin of the B complex group, and is required for optimal health, growth, and development. In humans, it cannot be synthesized de novo. As a cofactor or coenzyme, folate plays key biological roles in a variety of physiologic processes: maintenance and repair of the genome, regulation of gene expression, amino-acid metabolism, neurotransmitter synthesis, and the formation of myelin. Dietary folates must undergo multiple, tightly regulated absorption and metabolic processes before their cellular utilization occurs. Clinical conditions associated with abnormal body folate status are very diverse. They range from genetic syndromes defined prior to conception, to malformations that develop during embryogenesis (neural tube defects), to disorders that are postnatally acquired and progressive (e.g., cerebral folate deficiency, or folinic acid-responsive seizures). Central nervous system folate deficiency or impaired availability can occur in the settings of normal or decreased systemic folate levels. Because the majority of patients respond to treatment with folinic acid, pediatric neurologists should remain vigilant to the possibility of deficiencies of folate in patients with unexplained neurologic disorders. The deleterious outcomes of untreated patients underscore the importance of making an early diagnosis.  相似文献   
39.
From 1991-1995, the war in Croatia cost tens of thousands of lives (approximately 11834 persons killed between 1991-1994), and human rights abuses led to significant numbers of disappeared persons (3052). A total of 2395 families were searching for one disappeared person and 168 families of disappeared were searching for more than one person. 2035 men were reported disappeared and 528 women. However, while the majority or 60% (1226) of the men were between the ages of 18-49, 83% (438) of the women were between the ages of 50-96. Though the majority of missing persons of both genders were civilians, the disappeared women were more likely to be civilians (99%) than the disappeared men (52%), though only 23% of the men were regular army military personnel. The majority (55%) of men were previously engaged in paid employment, while 81% of women were farm or housewives, or pensioners. Most men (53%) were reported by informants to have disappeared outside of their home, while the majority (75%) of women disappeared from their home. Among those searching for the disappeared, 27% of those searching for men believed the person was alive or might still be alive, in contrast, only 18% of those searching for women believed them still alive. An important gender difference occurred in the pattern of disappearance in Croatia; most disappeared men were of combatant age, employed, and similar to the general population in key demographic characteristics, while most disappeared women were rural, less educated, and elderly.  相似文献   
40.
In this study DC numbers, phenotype and DC responses to the Toll-like receptor (TLR)-3 ligand, poly I:C, were examined in new-onset Type 1 diabetes (T1D) patients (ND) and in established T1D patients (ED). Absolute blood myeloid DC (MDC) and plasmacytoid DC (PDC) numbers were decreased in ND and ED patients compared to age-matched controls. The decrease in MDC and PDC counts was less evident in patients with a combination of T1D and coeliac disease (CD) or CD alone. The age-dependent decline in blood DC numbers, found in control children, was not evident in ND patients, such that 2-10 years old ND children had similar MDC and PDC numbers to 15-17 years old controls. In ED patients the t-score of MDC and PDC numbers related to the age of diagnosis but not to disease duration. Blood DC in T1D patients were not distinguished from those of controls by the levels of HLA-DR, CD40 and CD86 expression or the percentage of DC expressing cytokines, IL-12, IL-10, IL-6 and TNF-alpha, in responses to poly I:C. If low DC numbers are shown to contribute to the autoimmunity in T1D, interventions aimed to increase DC numbers may mitigate against beta-cell loss.  相似文献   
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