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131.
At most, many protein-misfolding diseases develop as environmentally induced sporadic disorders. Recent studies indicate that the dynamic interplay between a wide repertoire of noncoding RNAs and the environment play an important role in brain development and pathogenesis of brain disorders. To elucidate this new issue, novel animal models which reproduce the most prominent disease manifestations are required. For this, transgenic Drosophila strains were constructed to express small highly structured, non-coding RNA under control of a heat shock promoter. Expression of the RNA induced formation of intracellular aggregates revealed by Thioflafin T in embryonic cell culture and Congo Red in the brain of transgenic flies. Also, this strongly perturbed the brain control of locomotion monitored by the parameters of sound production and memory retention of young 5-day-old males. This novel model demonstrates that expression of non-coding RNA alone is sufficient to trigger neuropathology.  相似文献   
132.
Germ line inactivating mutations in BRCA1 confer susceptibility for breast and ovarian cancer. However, the relevance of the many missense changes in the gene for which the effect on protein function is unknown remains unclear. Determination of which variants are causally associated with cancer is important for assessment of individual risk. We used a functional assay that measures the transactivation activity of BRCA1 in combination with analysis of protein modeling based on the structure of BRCA1 BRCT domains. In addition, the information generated was interpreted in light of genetic data. We determined the predicted cancer association of 22 BRCA1 variants and verified that the common polymorphism S1613G has no effect on BRCA1 function, even when combined with other rare variants. We estimated the specificity and sensitivity of the assay, and by meta-analysis of 47 variants, we show that variants with <45% of wild-type activity can be classified as deleterious whereas variants with >50% can be classified as neutral. In conclusion, we did functional and structure-based analyses on a large series of BRCA1 missense variants and defined a tentative threshold activity for the classification missense variants. By interpreting the validated functional data in light of additional clinical and structural evidence, we conclude that it is possible to classify all missense variants in the BRCA1 COOH-terminal region. These results bring functional assays for BRCA1 closer to clinical applicability.  相似文献   
133.
This study aimed to evaluate the effect of surgically assisted rapid palatal expansion on the skeletal structures of the midface. Ten patients (mean age 28.5 years) were investigated by means of acoustic rhinometry, study model analysis and sonography before and after the procedure of surgically assisted rapid palatal expansion. The measurements revealed that surgically assisted rapid palatal expansion not only resulted in transverse expansion of the maxilla, providing dental arch space for lining up the teeth; the procedure also caused a substantial enlargement of the maxillary apical base and of the palatal vault, providing space for the tongue for correct swallowing and thus preventing relaps. There was a distinct subjective improvement in nasal breathing associated with enlargement of the nasal valve towards normal values and with an increase of nasal volume in all compartments. The measurements showed a marked influence of surgically assisted rapid palatal expansion on the skeletal structures of the midface. The significant widening can be demonstrated by non-invasive examination. Success of the osteotomy procedure can be readily monitored by sonographic examination of the expansion and the subsequent ossification, which allows individually adjusted retention periods and avoids frequent radiation exposure. Zusammenfassung In der vorliegenden Untersuchung sollten die Auswirkungen der chirurgisch unterstützten Gaumennahterweiterung auf dentoalveoläre, maxillär-basale und nasale Strukturen des Gesichtsschädels mit nicht invasiven Untersuchungstechniken evaluiert werden. Dazu wurden zehn erwachsene Patienten vor und nach chirurgisch unterstützter Gaumennahterweiterung mittels reflexionsakustischer Rhinometrie, Modellanalyse und Sonographie untersucht. Es zeigte sich, dass die chirurgisch unterstützte Gaumennahterweiterung auch beim erwachsenen Patienten nicht nur zu einer transversalen dentoalveolären Dehnung des Oberkiefers (Platz im Zahnbogen zur Ausrichtung der Zähne) führt, sondern auch die apikale Oberkieferbasis und das Gaumenvolumen (Platz für die Zunge beim regelrechten Schlucken und damit Rezidivprophylaxe) werden entscheidend vergrößert. Die chirurgische Gaumennahterweiterung führt darüber hinaus zu einer deutlichen Vergrößerung von Nasenvolumen und Nasenklappe mit auch subjektiver Verbesserung der Nasenatmung. Sonographisch waren die Segmentbewegung im Laufe der Dehnung ebenso nachweisbar wie die spätere Reossifizierung und vollständige Rekortikalisierung. Die Messungen belegen einen ausgeprägten Einfluss der chirurgisch unterstützten Gaumennahterweiterung auf die skelettalen Strukturen des Mittelgesichtes, deren deutliche Weitung durch nicht invasive Untersuchungsverfahren nachweisbar ist. Die sonographische Untersuchung kann den Fortschritt der transversalen Dehnung objektivieren und erlaubt eine individuelle Anpassung der Retentionszeit ohne zusätzliche Strahlenexposition.  相似文献   
134.
Background: The flaps used in reconstructive surgery are prone to ischemia and hypoxia, which imply a considerable risk of wound-healing complications. During normovolemic hemodilution, the oxygenation may further deteriorate because of the lack of erythrocytes or improve because of increased microcirculatory blood flow. The aim of this study was to investigate the net effect of normovolemic hemodilution of various degrees on the microcirculation and oxygenation in ischemic flap tissue in adult minipigs.

Methods: A rectangular flap was raised in the middle of the epigastrium, consisting of an adequately perfused portion and a partly ischemic portion. The animals were randomly assigned to either the control group (n = 10) or the experimental group (n = 10) receiving graded normovolemic hemodilution with 6% hydroxyethyl starch 200-0.5.

Results: Normovolemic hemodilution caused a significant linear increase in total blood flow to the flap (measured by transit time flowmetry). In the ischemic flap tissue, both oxygen tension (measured by polarographic cells) and venous base excess were transiently improved during hemodilution (F = 4.79 and P = 0.019 for the regression of tissue oxygen tension on hemoglobin and hemoglobin squared, and F = 4.18 and P = 0.029 for base excess). The expected values reached a peak at hemoglobin concentrations of 9.1 and 8.5 g/dl, respectively. The measured values at this level of hemodilution were 17 +/- 10.7 mmHg (mean +/- SD) versus 7.6 +/- 1.9 mmHg (baseline) for oxygen tension and -1.7 +/- 3.4 versus -5.6 +/- 4.1 mm for venous base excess.  相似文献   

135.
To clarify the sorting mechanism of the lysosomal/granular proteoglycan serglycin, we treated human promonocytic U937 cells with p-nitrophenyl-beta-D-xyloside (PNP-xyl) and cycloheximide. In the absence of protein synthesis, the carbohydrate moiety of serglycin was synthesized as PNP-xyl-chondroitin sulfate (CS), and most of it was delivered to lysosomes and degraded. Further, an augmented lysosomal targeting of serglycin in the presence of tunicamycin suggested that a sorting/lectin receptor with multiple specificity was involved with an increased capacity for serglycin in the absence of N-glycosylation. Correspondingly, the cation-independent mannose 6-phosphate receptor (CI-MPR) and sortilin were observed to bind to immobilized CS. These receptors were eluted in the presence of 200-400 mM and 100-250 mM NaCl, respectively. After treating the cells with a cross-linking reagent, a portion of the sulfated proteoglycan was coimmunoprecipitated with the CI-MPR but not with sortilin. In the presence of phorbol ester, lysosomal targeting of serglycin and to a lesser extent, of cathepsin D was inhibited. We conclude that the CI-MPR participates in lysosomal and granular targeting of serglycin and basic proteins such as lysozyme associated with the proteoglycan in hematopoietic cells.  相似文献   
136.
This paper proposes an innovative use of data mining and visualization techniques for decision support in planning and regional-level management of Slovenian public health-care. Data mining and statistical techniques were used to analyze databases collected by a regional Public Heath Institute. We also studied organizational aspects of public health resources in the selected Celje region with the objective to identify the areas that are atypical in terms of availability and accessibility of public health services for the population. The most important step was the detection of outliers and the analysis of availability and accessibility deviations. The results are applicable to health-care planning and support in decision making by local and regional health-care authorities. In addition to the practical results, which are directly useful for decision making in planning of the regional health-care system, the main methodological contribution of the paper are the developed visualization methods that can be used to facilitate knowledge management and decision making processes.  相似文献   
137.
We have developed a telemedicine system for blood transfusion work, to supply the local hospital laboratory with an expert opinion from the central reference laboratory. The telemedicine system allows remote inspection and interpretation of pre-transfusion tests, which are performed by ID-cards (micro-tube gel technology). The system was installed at three blood transfusion laboratories in Slovenia, approximately 70 km apart. Validation of the telemedicine system was performed using 99 clinical cases selected randomly from routine work. Two groups of immunohaematology specialists participated. Group A (n = 8) performed the read-out of the pre-transfusion tests on ID-cards by using the telemedicine system. Group B (n = 2) then read the ID-cards independently using the standard visual method. All 98 final interpretations which were recorded using the telemedicine system were correct. We recorded 591 micro-tube read-outs of agglutination strength using the telemedicine system, of which 582 were correct. For comparison, we recorded 591 micro-tube read-outs using the standard visual method, of which 582 were correct. The validation proved that the telemedicine system was suitable for operational use.  相似文献   
138.
Stancak A  Raij TT  Pohja M  Forss N  Hari R 《NeuroImage》2005,26(3):793-800
Noxious stimulation activates-in addition to the brain structures related to sensory, emotional, and cognitive components of pain-also the brain's motor system. Effect of noxious input on the primary motor (MI) cortex remains, however, poorly understood. To characterize this effect in more detail, we quantified the ongoing oscillatory communication between the MI cortex and hand muscles during selectively noxious laser stimulation. The subjects maintained an isometric contraction of finger muscles while receiving the laser stimuli to the dorsum of the hand. Tactile stimuli with well-known effects on the MI cortex reactivity served as control stimuli. Cortex-muscle coherence was computed between magnetoencephalographic (MEG) signals from the contralateral MI and electromyographic (EMG) signals from the hand muscles. Statistically significant coherence at approximately 20 Hz was found in 6 out of 7 subjects. The coherence increased phasically after both types of stimuli but significantly later after laser than tactile stimuli (mean +/- SEM peak latencies 1.05 +/- 0.12 s vs. 0.58 +/- 0.06 s; P < 0.05), and the coherence increase lasted longer after laser than tactile stimuli (0.87 +/- 0.09 s vs. 0.50 +/- 0.06 s, P < 0.05). The observed coherence increase could be related to stabilization of the motor-cortex control after sensory input. Our findings add to the clinically interesting evidence about the cortical pain-motor system interaction.  相似文献   
139.
BACKGROUND: Impaired glucose tolerance (IGT) is associated with endothelial dysfunction and upregulation of inflammatory markers, which is potentially reversible by adequate treatment. It was our aim to compare the impact of exercise training with that of rosiglitazone on endothelial function and inflammatory markers in patients with IGT and coronary artery disease (CAD). METHODS: Patients with IGT and CAD were randomly assigned to either exercise training (n=13), rosiglitazone (8 mg; n=11), or a control group (n=10). During the first week, exercise training consisted of 6 x 15 min/d followed by three weeks of 30 min/d submaximal ergometer exercise. In addition, group exercise training of 1 h was performed twice per week. RESULTS: After 4 weeks, triglycerides and uric acid were significantly lower in the exercise group whereas fasting glucose, HbA1c, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, C-reactive protein, fibrinogen, and body mass index did not differ between groups. In the exercise group, exercise capacity (123+/-33 vs. 144+/-31 W; P=0.006) and endothelium-dependent, flow-mediated vasodilatation (P<0.01) increased significantly, whereas in the rosiglitazone group and in the control group (P=n.s.) no changes were seen. CONCLUSION: In patients with IGT and CAD, 4 weeks of exercise training exert significant and superior improvement of endothelium-dependent vasodilatation as compared with rosiglitazone therapy or usual care. This finding should be seen as an even further encouragement to recommend and, where available, prescribe exercise training to our patients.  相似文献   
140.

Background

Recent investigations have confirmed an important stabilizing and protective function of the meniscofemoral ligaments (MFLs) to the knee joint and suggest a clinical relevance. Concerning their incidences, however, there have been discrepancies between data acquired from cadaveric studies and MRI data using 0.3- to 1.5-Tesla field strengths probably due to lower resolution. This study aims to investigate whether imaging with 3-Tesla magnetic resonance imaging (3-T MRI) is beneficial in gaining information regarding the ligaments' incidence, length, width and anatomic variation.

Methods

3-T MRI images of 448 patients (224 males, 224 females, with, respectively, 32 patients of each sex in the age groups: 0–20, 21–30, 31–40, 41–50, 51–60, 61–70, > 70 years) were retrospectively reviewed. The influence of the parameters ‘sex’ and ‘age’ was determined.

Results

Whereas 71% of the patients had at least one MFL, 22% had an anterior MFL (aMFL), 53% had a posterior MFL (pMFL) and five percent had coexisting ligaments. The pMFLs were more likely to be present in female patients (P < 0.05) but if so, they were longer in the males (P < 0.05). The pMFL was categorized according to its insertion on the medial femoral condyle.

Conclusions

3-T MRI enables an excellent illustration of the anatomic variations of pMFLs. By modifying an anatomic classification for radiological use we measured lengths and widths of the MFLs without any difficulties. Despite its increased resolution, 3-T MRI lends no diagnostic benefit in visualizing the course of the aMFL or filigree coexisting ligaments as compared to MRI at lower field strengths.  相似文献   
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