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141.
Pollen grains from the plant cover of a given area participate largely in the composition of aeroflora (pollen and molds) of this area. Association of allergic respiratory disorders with concentration of allergenic particles in the atmosphere is well documented, and aerobiologic studies are of great relevance. A 10-year volumetric aerobiologic study was conducted in the city of Heraklion, located in the center of the north-shore of the island of Crete, Greece. Main allergenic families and genera encountered were, in descending order of frequency Oleaceae, Quercus, Platanaceae, Cupressaceae, Pinaceae, Populus, Moraceae, and Corylaceae. Concentrations noted for most of these aeroallergens were much lower than those reported from other European regions. In parallel, an atopic population of 576 individuals, exhibiting allergic symptoms mainly of the respiratory tract were subjected to a battery of skin-prick tests. A fair degree of agreement between total pollen counts and positive skin-prick test frequencies for the families of Oleaceae, Platanaceae, and Cupressaceae was noted. On the contrary a poor degree of concordance was noted for the rest of the families and genera.  相似文献   
142.
Atrial flutter or tachycardia may coexist with atrial fibrillation [AF] and can be treated with ablation techniques in attempt to reduce the total AF burden. The role of ablation of latent atrial tachyarrhythmias elicited at electrophysiologic study in conjunction with atrial pacing and antiarrhythmic drugs in patients with refractory AF has not been evaluated. We evaluated the efficacy of catheter ablation of electrically induced atrial flutter or atrial tachycardia in improving rhythm control in patients with refractory AF. Methods: Consecutive patients with refractory AF, and spontaneous atrial flutter (Group 1) or without spontaneous atrial flutter (Group 2) underwent programmed stimulation in a baseline drug-free state. All patients had electrically induced atrial flutter or tachycardia. Radiofrequency ablation of the arrhythmia substrate was performed in all patients. Primary endpoints evaluated for patient outcome in both groups included maintenance of rhythm control and freedom from recurrent atrial tachyarrhythmias. Results: Forty-three patients, with a mean age of 66±13 years were studied. Group 1 consisted of 22 patients while Group 2 had 21 patients. Ablation of the tricuspid valve-inferior venacaval isthmus was performed in 41 patients who had common atrial flutter induced at electrophysiologic study. Ablation of other atrial sites was performed in 8 patients with induced atypical flutter and 4 patients with induced atrial tachycardia. Ten of these patients had ablation of more than one arrhythmia. 17 patients (40%) had atrial pacing instituted and 28 patients remained on a class 1/3 antiarrhythmic drug. During a mean follow-up of 26±14 months, 33 patients (82.5%) remained in rhythm control. Actuarial analysis showed 96% of patients in rhythm control at 6 months, 94% at 12 months, and 90% at 24 months. Freedom from symptomatic AF recurrence was 64% at 6 months, 58% at 12 months, and 42% at 24 months. The outcome for both of these endpoints was similar for Group 1 and Group 2 (p = NS). The AF free interval increased significantly from 7±9 days to 172±121 days (p < 0.01) after ablation. This increase was again similar in both the groups. In the 14 patients were who did not receive atrial pacing and who remained on the same class 1/3 antiarrhythmic drug, the AF free interval increased from 18±17 days to 212±102 days (p < 0.01). Conclusions: We conclude that electrophysiologic studies can elicit latent atrial flutter or tachycardia in patients with refractory AF without spontaneous monomorphic atrial tachyarrhythmias. Catheter ablation of electrically induced atrial flutter or tachycardia either alone, or with atrial pacing and with antiarrhythmic drug may improve rhythm control and reduce AF recurrences. This is similar in patients with and without spontaneous atrial flutter and refractory AF.  相似文献   
143.
Similarities in cyclic vomiting syndrome across age groups   总被引:6,自引:0,他引:6  
OBJECTIVE: Cyclic vomiting syndrome is well recognized in children yet has poorly defined pathogenesis and treatment. Cyclic vomiting syndrome is occasionally diagnosed in older subjects, but little attempt has been made to determine if such cases represent a unique disorder. METHODS: We reviewed clinical data from 39 patients aged 1.8-75 yr with cyclic vomiting syndrome meeting published criteria for diagnosis. Clinical characteristics were compared between subjects with symptom onset in childhood (<12 yr, n = 18) and subjects with onset at an older age (> or =12 yr, n = 21; mean age at onset 34.8+/-3.8 yr). RESULTS: All patients had stereotypical episodes of vomiting separated by varying symptom-free intervals. The prevalence rates of prodromal symptoms, triggering events, alleviants, associated symptoms including abdominal pain and diarrhea, and past or family history of migraine were similar in the children and older subjects with the syndrome (p > 0.3 for each). Delay in diagnosis was greater in the older subset (3.1+/-0.8 yr vs 7.9+/-3.1 yr, p < 0.05). Interepisode intervals and total number of hospitalizations did not differ significantly between younger and older patients, but duration of episodes was significantly longer in the older group (2.0+/-0.5 days vs 3.8+/-0.4 days, p < 0.01). When subjects were further substratified by age of illness onset, duration of episodes progressively increased from infant/toddlers (1.8+/-0.4 days) through childhood (2.3+/-0.5 days) and adolescence (2.9+/-1.0 days) and into adulthood (3.9+/-0.5; p < 0.05 across groups). Episode duration did not lengthen further in subgroups >20 yr of age. CONCLUSIONS: Many characteristics of cyclic vomiting syndrome are similar irrespective of age at disorder onset, suggesting a uniform pathogenesis. Duration of episodes increases with age to age 20 yr. Increased awareness of the condition and a high index of suspicion may help decrease delay in diagnosis after symptom onset.  相似文献   
144.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Present study was undertaken to optimize the extraction conditions for the recovery of anthocyanins from an...  相似文献   
145.
146.
Microparticles (MPs) resulting from vesiculation of different cell types in Plasmodium falciparum infection correlate with the level of proinflammatory cytokine TNF that may thereby determine the disease severity. Using TruCount tube based flow cytometric method for the exact quantification of MP and enzyme linked immunosorbent assay for the measurement of TNF, we conducted a hospital based case control study on P. falciparum malaria patients to scrutinize and infer the link between the two. In 52 cerebral malaria (CM), 21 multi-organ-dysfunction (MOD), 12 non cerebral severe malaria (NCSM) and 43 uncomplicated malaria patients, the MP level was found to be significantly elevated in febrile malaria patients compared to healthy controls and a striking decrease in MP level was observed with the clearance of the P. falciparum infection in the patients upon follow-up. The lowering of the parasite density with the level of plasma TNF and the positive correlation of the cytokine with the cell derived MPs and negative correlation with the respective cell count in human malaria patients suggests that TNF may be a key stimulant to the cells resulting in the release of MPs in malaria infection.  相似文献   
147.
Grand means of time‐varying signals (waveforms) across subjects in magnetoencephalography (MEG) and electroencephalography (EEG) are commonly computed as arithmetic averages and compared between conditions, for example, by subtraction. However, the prerequisite for these operations, homogeneity of the variance of the waveforms in time, and for most common parametric statistical tests also between conditions, is rarely met. We suggest that the heteroscedasticity observed instead results because waveforms may differ by factors and additive terms and follow a mixed model. We propose to apply the asinh‐transformation to stabilize the variance in such cases. We demonstrate the homogeneous variance and the normal distributions of data achieved by this transformation using simulated waveforms, and we apply it to real MEG data and show its benefits. The asinh‐transformation is thus an essential and useful processing step prior to computing and comparing grand mean waveforms in MEG and EEG.  相似文献   
148.

The assembly of striated muscle myofibrils is a multistep process in which a variety of proteins is involved. One of the first and most important steps in myofibrillogenesis is the arrangement of thin myofilaments into ordered I-Z-I brushes, requiring the coordinated activity of numerous actin binding proteins. The early expression of myopodin prior to sarcomeric α-actinin, as well as its binding to actin, α-actinin and filamin indicate an important role for this protein in actin cytoskeleton remodelling with the precise function of myopodin in this process yet remaining to be resolved. While myopodin was previously described as a protein capable of cross-linking actin filaments into thick bundles upon transient transfections, it has remained unclear whether myopodin alone is capable of bundling actin, or if additional proteins are involved. We have therefore investigated the in vitro actin binding properties of myopodin. High speed cosedimentation assays with skeletal muscle actin confirmed direct binding of myopodin to F-actin and showed that this interaction is mediated by at least two independent actin binding sites, found in all myopodin isoforms identified to date. Furthermore, low-speed cosedimentation assays revealed that not only full length myopodin, but also the fragment containing only the second binding site, bundles microfilaments in the absence of accessory proteins. Ultrastructural analysis demonstrated that this bundling activity resembled that of α-actinin. Biochemical experiments revealed that bundling was not achieved by myopodin’s ability to dimerize, indicating the presence of two individual F-actin binding sites within the second binding segment. Thus full length myopodin contains at least three F-actin binding sites. These data provide further understanding of the mechanisms by which myopodin contributes to actin reorganization during myofibril assembly.

  相似文献   
149.
Abstract

As mannose receptors are known to be over-expressed in cancer cells, we synthesized polymannose-doxorubicin (PM-DOX) conjugates with the objective of targeting the drug to cancer cells. DOX was conjugated to oxidized PM through Schiff’s linkages to obtain PM-DOX conjugates. In order to examine the superior targeting efficacy of PM-DOX conjugate, sodium alginate (SA) was conjugated to DOX by similar chemistry and compared with PM-DOX conjugate. The cytotoxicity of the conjugates was investigated in A549 cell lines using MTT Assay and the cell uptake and retention studies, were performed using flow cytometry and cell imaging. In vitro drug release studies with both PM-DOX and SA-DOX conjugates showed an initial burst release of DOX up to 37–39% at 1?h, followed by a steady release up to 58–62% at 24?h in human plasma while negligible release was observed in phosphate buffered saline. The conjugates exhibited negligible hemolytic potential to human erythrocytes compared to free DOX. The PM-DOX conjugate showed better cytotoxic potential against A549 cells at lower concentration (equivalent to 0.27?μg/mL of DOX) at 72?h compared to free DOX and SA-DOX conjugate. Further, PM-DOX conjugate showed enhanced uptake by the cells in comparison with SA-DOX conjugate thereby confirming the target specificity of PM to the cancer cells.  相似文献   
150.
Protein aggregation and ordered fibrillar amyloid deposition inside and outside of the central nervous system cells is the common pathologic hallmark of most aging-related neurodegenerative disorders. Dominant mutations in the gene encoding superoxide dismutase 1 (SOD1) protein are linked to familial amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by progressive degeneration of motor neurons, leading to muscle paralysis and death. The major histochemical hallmark in the remaining motor neurons of ALS is the intracellular accumulation of ubiquitinated inclusions consisting of insoluble aberrant protein aggregates. However, the molecular pathomechanisms underlying the process have been elusive. Here for the first time, we report that E6-AP, a homologous to E6-AP C terminus-type E3 ubiquitin ligase depleted in ALS mouse models before neurodegeneration. E6-AP coimmunoprecipitates with the SOD1 protein and is predominantly mislocalized in mutant SOD1-containing inclusion bodies. Overexpression of E6-AP increases the ubiquitination and facilitates degradation of SOD1 proteins. Finally, we show that the overexpression of E6-AP suppresses the aggregation and cell death mediated by mutated SOD1 proteins and cellular protective effect is more prominent when E6-AP is overexpressed along with Hsp70. These data suggest that enhancing the activity of E6-AP ubiquitin ligase might be a viable therapeutic strategy to eliminate mutant SOD1-mediated toxicity in ALS.  相似文献   
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