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991.
Amyloid in surgical pathology 总被引:7,自引:0,他引:7
Amyloid is defined as a proteinaceous tissue deposit that shows a typical green birefringence in polarized light after staining with Congo red, the presence of non-branching linear fibrils of indefinite length with a mean diameter of 10 nm, and a distinct X-ray diffraction pattern consistent with Pauling's model of a cross -fibril. Amyloid may deposit locally or may present as a systemic disease. The origin of amyloid is diverse: 25 different fibril proteins have been described so far. The precursor proteins differ from each other in their primary structures and functions. The only common denominator is the propensity to form anti-parallel cross -fibrils under certain circumstances. Early diagnosis of amyloid is still a major challenge in surgical pathology. Histological proof can be obtained using Congo-red staining and polarization microscopy. However, small deposits may be difficult to discern, and sensitivity can be improved using fluorescence microscopy. Classification of amyloid is mandatory, since amyloid is treatable and different treatment regimens are applied to different amyloid diseases. This review focuses on the epidemiology, clinical features, pathology and diagnosis of amyloid in surgical pathology. 相似文献
992.
The Lyme disease spirochete, Borrelia burgdorferi, inhabits the gut lumen of the tick vector. At this location the spirochete is exposed to host blood when a tick feeds. We report here on studies that were done with normal and complement-deficient (C3-knockout) mice to determine if the host complement system killed spirochetes within the vector. We found that spirochete numbers within feeding nymphs were not influenced by complement, most likely because host complement was inactivated within the vector. The Lyme disease outer surface protein A (OspA) vaccine is a transmission-blocking vaccine that targets spirochetes in the vector. In experiments with mice hyperimmunized with OspA, complement was not required to kill spirochetes within nymphs and to block transmission from nymphs to the vaccinated host. However, host complement did enhance the ability of OspA antibody to block larvae from acquiring spirochetes. Thus, the effects of OspA antibody on nymphal transmission and larval acquisition appear to be based on different mechanisms. 相似文献
993.
A recurrent chromosome translocation breakpoint in breast and pancreatic cancer cell lines targets the neuregulin/NRG1 gene 总被引:2,自引:0,他引:2
994.
Dai Z Weichenhan D Wu YZ Hall JL Rush LJ Smith LT Raval A Yu L Kroll D Muehlisch J Frühwald MC de Jong P Catanese J Davuluri RV Smiraglia DJ Plass C 《Genome research》2002,12(10):1591-1598
Knudson's two-hit hypothesis postulates that genetic alterations in both alleles are required for the inactivation of tumor-suppressor genes. Genetic alterations include small or large deletions and mutations. Over the past years, it has become clear that epigenetic alterations such as DNA methylation are additional mechanisms for gene silencing. Restriction Landmark Genomic Scanning (RLGS) is a two-dimensional gel electrophoresis that assesses the methylation status of thousands of CpG islands. RLGS has been applied successfully to scan cancer genomes for aberrant DNA methylation patterns. So far, the majority of this work was done using NotI as the restriction landmark site. Here, we describe the development of RLGS using AscI as the restriction landmark site for genome-wide scans of cancer genomes. The availability of AscI as a restriction landmark for RLGS allows for scanning almost twice as many CpG islands in the human genome compared with using NotI only. We describe the development of an AscI-EcoRV boundary library that supports the cloning of novel methylated genes. Feasibility of this system is shown in three tumor types, medulloblastomas, lung cancers, and head and neck cancers. We report the cloning of 178 AscI RLGS fragments via two methods by use of this library. 相似文献
995.
cagA Status and eradication treatment outcome of anti-Helicobacter pylori triple therapies in patients with nonulcer dyspepsia
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Broutet N Marais A Lamouliatte H de Mascarel A Samoyeau R Salamon R Mégraud F 《Journal of clinical microbiology》2001,39(4):1319-1322
The differences in eradication rates reported in clinical trials aiming to cure Helicobacter pylori infection cannot be entirely explained by the type of regimen, bacterial resistance, or lack of compliance. Using data from a clinical trial, a logistic regression model was constructed to determine whether cagA status, assessed by PCR, affects the outcome of eradication. Resistance to clarithromycin (10% of the strains) predicted failure perfectly. In the model (n = 156), a cagA-lacking strain (odds ratio [OR] = 2.2; 95% confidence interval [CI], (1.1 to 4.7), tobacco smoking OR = 3.1; 95% CI, 1.3 to 7.0), and a double dose of proton pump inhibitor in the treatment regimen (OR = 0.3; 95% CI, 0.2 to 0.7) were associated with the treatment outcome. The exact role of cagA in the outcome of H. pylori eradication therapy has not been explored. However, the type of histological lesions which it causes in the gastric mucosa may be implicated. Regardless of the mechanism involved, cagA status is a good predictive marker of eradication outcome. 相似文献
996.
Reactivity differences among human T cells from blood and lymphoid organs, analysed by limiting dilution: correlation with specific gravity and binding of peanut lectin.
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R J Van de Griend R Van Doorn L Stricker W P Zeijlemaker D Roos 《Clinical and experimental immunology》1981,45(2):376-385
Human T cells from peripheral blood, cord blood, thymus, spleen and lymph node were analysed for their proliferative response capacity to mitogens, for their specific gravity and size, and for their binding capacity of peanut agglutinin. A close correlation was found between these parameters: thymocytes and T cells from spleen were consistently heavier and smaller, and showed a lower proliferative response capacity, than T cells from blood or lymph node. Similarly, within each cell population, the small, heavy cells were least reactive. The limiting-dilution analysis revealed that heavy T cells from peripheral blood contain a lower number of reactive cells than the light peripheral T lymphocytes. Because heavy T cells from the thymus bound more peanut lectin than did light cells, it is speculated that the differences between T cells of high and low specific gravity might reflect differences in maturation level. 相似文献
997.
H. Arabi H. Vandewalle P. Pitor J. de Lattre H. Monod 《European journal of applied physiology》1997,76(2):122-127
The present experiment was designed to study the importance of strength and muscle mass as factors limiting maximal oxygen uptake (V˙O2 max ) in wheelchair subjects. Thirteen paraplegic subjects [mean age 29.8 (8.7) years] were studied during continuous incremental exercises until exhaustion on an arm-cranking ergometer (AC), a wheelchair ergometer (WE) and motor-driven treadmill (TM). Lean arm volume (LAV) was estimated using an anthropometric method based upon the measurement of various circumferences of the arm and forearm. Maximal strength (MVF) was measured while pushing on the rim of the wheelchair for three positions of the hand on the rim (?30°, 0° and +30°). The results indicate that paraplegic subjects reached a similar V˙O2 max [1.23 (0.34) l?·?min?1, 1.25 (0.38) l?·?min?1, 1.22?(0.18) l?·?min?1 for AC, TM and WE, respectively] and V˙O2 max /body mass [19.7?(5.2)?ml?·?min?1?·?kg?1, 19.5 (6.14) ml?·?min?1?·?kg?1, 19.18 (4.27) ml?·?min?1?·?kg?1 for AC, TM and WE, respectively on the three ergometers. Maximal heart rate f c max during the last minute of AC (173 (17) beats?·?min?1], TM [168 (14) beats?·?min?1], and WE [165 (16) beats?·?min?1], were correlated, but f c max was significantly higher for AC than for TM (P<0.03). There were significant correlations between MVF and LAV (P<0.001) and between the MVF data obtained at different angles of the hand on the rim [311.9 (90.1) N, 313.2 (81.2) N, 257.1 (71) N, at ?30°, 0° and +30°, respectively]. There was no correlation between V˙O2 max and LAV or MVF. The relatively low values of f c max suggest that V˙O2 max was, at least in part, limited by local aerobic factors instead of central cardiovascular factors. On the other hand, the lack of a significant correlation between V˙O2 max and MVF or muscle mass was not in favour of muscle strength being the main factor limiting V˙O2 max in our subjects. 相似文献
998.
Increased [Met]enkephalin and decreased substance P in spinal cord following thermal injury to one limb. 总被引:1,自引:0,他引:1
Thermal injury to one hind limb of rats was induced by immersion into water at 62 degrees C. Both a mild (15 s) or severe (30 s) lesion caused inflammation of the limb when observed 24 h later; but at this time the animals used the injured limb when they walked. Animals with a severe lesion of the injured limb subsequently withdrew it from use when walking. Limb withdrawal did not occur following a mild lesion. At 24 h following the lesion, lumbar spinal cord levels of [Met]enkephalin, as measured by radioimmunoassay, were elevated (70%) bilaterally in both hemisegments, ipsi- and contralateral to the lesion. At seven days following either mild or severe hind limb lesion [Met]enkephalin levels were elevated only in the ipsilateral lumbar hemisegment. At that time no changes in thoracic [Met]enkephalin levels were observed. Substance P levels were decreased (20-25%) bilaterally in the lumbar cord 24 h following a severe limb lesion, but no change was observed at seven days in any cord segment following a mild or severe lesion. Changes in spinal cord [Met]enkephalin content occur in response to thermal injury to one hind limb. However, the changes do not appear to be related to the withdrawal of the damaged limb from use following a severe lesion. Peptide changes in the spinal cord may reflect pain or injury to the damaged limb following a thermal lesion. In contrast, limb withdrawal may be a physiological rest mechanism related to altered basal ganglia peptide function. 相似文献
999.
Ezio Martuscelli Clara Silvestre Maurizio Canetti Claudia de Lalla Anna Bonfatti Alberto Seves 《Macromolecular chemistry and physics.》1989,190(10):2615-2625
The crystallization and the thermal behaviour of thin films of isotactic polypropylene/hydrogenated oligo(cyclopentadiene) of low molecular weight (iPP/HOCP) are studied using optical microscopy and differential scanning calorimetry (DSC). The spherulite growth rate, the overall crystallization rate and the equilibrium melting temperature of iPP are decreased by the addition of HOCP to iPP. This leads to the hypothesis that iPP and HOCP form a miscible blend in the amorphous phase. This hypothesis is also supported by the detection of a single blend-composition-dependent glass transition temperature of each blend as determined by DSC. 相似文献
1000.
A glycoprotein (gp-88) secreted by pseudorabies virus (PRV) infected cells was isolated and purified. Anti gp-88 antibodies were used to screen an expression library constructed in Escherichia coli using genomic PRV DNA. Two positive clones were identified and the cloned genetic information was used to localize the corresponding gene in the unique short region of the PRV genome. Antibodies to the glycoprotein were also used to identify the unglycosylated precursor as synthesized in an in vitro translation system. A major precursor of 65 kDa was detected. Although the glycoprotein described here was not found as a major structural glycoprotein of the virion, antibodies to gp-88 are able to neutralise viral activity in vitro. The possible relationship with known glycoproteins of PRV is discussed. 相似文献