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101.
Chorneyko K Giesler R Sabatino D Ross C Lobo F Shuhaibar H Chen V Elavathil L Denardi F Ansari S Salama S LeBlanc V Norman G Sheridan B Riddell R 《American journal of clinical pathology》2002,117(5):783-790
Telepathology (TP) uses telecommunication linkages to electronically capture, store, retrieve, and transmit images to distant sites. We assessed the feasibility of a dynamic real-time TP system for light microscopic (LM) diagnosis of anatomic pathology specimens, including frozen sections. Six pathologists, in 2 separate periods, read a set of 160 retrospectively retrieved slides (80 of which were frozen sections) by TP and LM. Reading times were recorded. Diagnoses were compared with the reference diagnosis (established by a group of 5 independent pathologists) and graded on a scale of 0 to 2 (2, correct; 1, incorrect but no clinical impact; 0, incorrect with clinical impact). Overall, LM was more accurate than TP compared with the reference diagnosis (score, 1.68 vs 1.54). There was no difference in accuracy between frozen section and paraffin-embedded tissue. Intraobserver agreement ranged from 82.5% to 88.2%. The average reading time was 6.0 minutes for TP and 1.4 minutes for LM. During the study, reading time decreased for TP but not for LM. These results show that despite marginally lower accuracy and longer reading times, TP isfeasible for routine light microscopic diagnosis, including frozen sections. 相似文献
102.
Guido Monga Gianna Mazzucco Francesco Paolo Rossini Franco Presti 《Virchows Archiv : an international journal of pathology》1979,382(3):355-360
Summary An unusual form of colorectal polyposis is described displaying juvenile, adenomatous and mixed patterns in a 17-year-old girl. Although juvenile polyposis is generally considered to be non-neoplastic in nature, in both the present and in other case reports histological findings support a neoplastic nature. Since an increase in the incidence of large bowel carcinomas has been found in subjects with a previous diagnosis of juvenile polyposis, these patients should be considered to be at risk, and submitted to follow up. 相似文献
103.
Niggli HJ Tudisco S Privitera G Applegate LA Scordino A Musumeci F 《Journal of biomedical optics》2005,10(2):024006
Photobiological research in the last 30 yr has shown the existence of ultraweak photon emission in biological tissue, which can be detected with sophisticated photomultiplier systems. Although the emission of this ultraweak radiation, often termed biophotons, is extremely low in mammalian cells, it can be efficiently increased by ultraviolet light. Most recently it was shown that UV-A (330 to 380 nm) releases such very weak cell radiation in differentiated human skin fibroblasts. Based on these findings, a new and powerful tool in the form of UV-A-laser-induced biophotonic emission of cultured cells was developed with the intention to detect biophysical changes between carcinogenic and normal cells. With suspension densities ranging from 1 to 8 x 10(6) cells/mL, it was evident that an increase of the UV-A-laser-light induced photon emission intensity could be observed in normal as well as melanoma cells. Using this new detection procedure of ultraweak light emission, photons in cell suspensions as low as 100 microL could be determined, which is a factor of 100 lower compared to previous procedures. Moreover, the detection procedure has been further refined by turning off the photomultiplier system electronically during irradiation leading to the first measurements of induced light emission in the cells after less than 10 micros instead of 150 ms, as reported in previous procedures. This improvement leads to measurements of light bursts up 10(7) photons/s instead of several hundred as found with classical designs. Overall, we find decreasing induction ratings between normal and melanoma cells as well as cancer-prone and melanoma cells. Therefore, it turns out that this highly sensitive and noninvasive device enables us to detect high levels of ultraweak photon emission following UV-A-laser-induced light stimulation within the cells, which enables future development of new biophysical strategies in cell research. 相似文献
104.
105.
Macchi C Popolizio A Casamorata F Bicchi S Pieroni A Molino Lova R Miniati B Gulisano M Catini C Conti AA Gensini GF 《Italian journal of anatomy and embryology = Archivio italiano di anatomia ed embriologia》2002,107(2):93-97
Fifty-four subjects, aged between 20 and 35 years, divided into two subgroups, respectively 30 healthy subjects (17 males and 13 females) and 24 subjects with "gonalgia sine materia" (13 males and 11 females) underwent isokinetic exercise test in order to compare their dominant limb with the not dominant one as regard as the strength of extensor and flexor muscles of the knee. No statistically significant difference was found in any of the studied parameters in the comparison between the dominant limb and the not dominant one, both within the subgroup of healthy subjects and within the subgroup of subjects with "gonalgia sine materia". Authors conclude that psychological features may play a preeminent role in the genesis, as well as in the maintenance of "gonalgia sine materia", thus confirming previous data available in medical literature. 相似文献
106.
Zannolli R Mostardini R Pucci L Sorrentino L Biagioli M Perotti R Guarna M Hadjistilianou T Zerega G Pierluigi M Franco B D'Ambrosio A Morgese G 《American journal of medical genetics》2001,102(1):29-35
We report on a 2-year-old girl with a de novo mutation [45,XX,der(5),t(5;14) (pter;q11.2)] with corpus callosum agenesis, multiple cysts (cerebral and cardiac), subtle eye abnormalities, and at least two different skin defects, strongly indicating neuroectodermal involvement, as a neuromuscular choristoma (hamartoma) and an eccrine hamartoma. Fluorescent in situ hybridization with different single-locus probes showed that chromosome 5 has a very small deletion, confined to a region composed of repetitive sequences. By contrast, the long (q) arm of chromosome 14 seems to be much more involved in the rearrangement, with partial monosomy spanning from the centromere to the D14S72 and D14S261 loci. The extent of the deleted region of chromosome 14 is approximately 16 cM. To our knowledge, this is the smallest reported deletion involving the chromosome 14q11.2 region to be associated with a developmental disorder resulting in variable eye, skin, and brain anomalies. We suggest that a new syndrome, mimicking in some ways the MLS phenotype, is caused by a deletion in the chromosome 14q11.2 region. 相似文献
107.
Spadoni F Stefani A Morello M Lavaroni F Giacomini P Sancesario G 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,135(4):544-551
Prolonged exposure to manganese in mammals may cause an extrapyramidal disorder characterized by dystonia and rigidity. Gliosis in the pallidal segments underlies the well-established phase of the intoxication. The early phase of the intoxication may be characterized by psychic, nonmotor signs, and its morphological and electrophysiological correlates are less defined. In a rat model of manganese intoxication (20 mg/ml in drinking water for 3 months), neither neuronal loss nor gliosis was detected in globus pallidus (GP). However, a striking vulnerability of manganese-treated GP neurons emerged. The majority of GP neurons isolated from manganese-treated rats died following brief incubation in standard dissociation media. In addition, patch-clamp recordings in the whole-cell configuration were not tolerated by surviving GP neurons. Neither coeval but untreated GP neurons nor striatal ones manifested analogous susceptibility. Using the perforated-patch mode of recording we attempted at identifying the functional hallmarks of GP vulnerability: in particular, voltage-gated calcium currents and glutamate-induced currents were examined. Manganese-treated GP neurons exhibited calcium currents similar to control cells aside from a slight reduction in the dihydropyridine-sensitive current facilitation. Strikingly, manganese-treated GP cells--but not striatal ones--manifested peculiar responses to glutamate, since repeated applications of the excitatory amino acid, at concentrations which commonly promote desensitizing responses, produced instead an irreversible cell damage. Possible mechanisms are discussed. 相似文献
108.
Immunoreactivity of a surface wall fraction produced by spherules of Coccidioides immitis. 总被引:1,自引:9,他引:1
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G T Cole T N Kirkland M Franco S Zhu L Yuan S H Sun V M Hearn 《Infection and immunity》1988,56(10):2695-2701
The membranous spherule outer wall (SOW) isolated from liquid cultures of Coccidioides immitis has been shown to elicit reactivity with human anti-Coccidioides antibody by immunofluorescence and the immunodiffusion-tube precipitin assay. The serologically reactive components were extracted from SOW with the nonionic detergent N-octyl-beta-D-glucopyranoside (OG). The OG-soluble fraction of SOW was shown to be reactive with immunoglobulin G in 25 serum samples from coccidioidomycosis patients by an enzyme-linked immunosorbent assay. The isolated SOW and OG-soluble fraction of SOW were also demonstrated to be capable of eliciting lymphocyte blastogenesis. The antigenic and protein compositions of the OG-soluble fraction were examined by two-dimensional immunoelectrophoresis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), respectively. Two antigens which were extracted from SOW were identified as antigens 2 and CS on the basis of the coccidioidin-anticoccidioidin reference system. The latter was isolated earlier and shown to correspond to a molecular mass (Mr) of 19 X 10(3) by SDS-PAGE under reducing conditions. This same electrophoresis band was shown to be reactive with sera from coccidioidomycosis patients by immunoblot analysis. One other SDS-PAGE component of the OG-soluble fraction of SOW with an Mr of 66 X 10(3) was shown to be reactive with sera from patients by immunoblot analysis. The SOW of C. immitis represents an important reservoir of immunoreactive wall components which has not previously been reported. 相似文献
109.
Histone deposition protein Asf1 maintains DNA replisome integrity and interacts with replication factor C 总被引:9,自引:0,他引:9
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Chromatin assembly and DNA replication are temporally coupled, and DNA replication in the absence of histone synthesis causes inviability. Here we demonstrate that chromatin assembly factor Asf1 also affects DNA replication. In budding yeast cells lacking Asf1, the amounts of several DNA replication proteins, including replication factor C (RFC), proliferating cell nuclear antigen (PCNA), and DNA polymerase epsilon (Pol epsilon), are reduced at stalled replication forks. In contrast, DNA polymerase alpha (Pol alpha) accumulates to higher than normal levels at stalled forks in asf1Delta cells. Using purified, recombinant proteins, we demonstrate that RFC directly binds Asf1 and can recruit Asf1 to DNA molecules in vitro. We conclude that histone chaperone protein Asf1 maintains a subset of replication elongation factors at stalled replication forks and directly interacts with the replication machinery. 相似文献
110.
Genetic instability in superficial bladder cancer and adjacent mucosa: an interphase cytogenetic study 总被引:5,自引:0,他引:5
Cianciulli AM Leonardo C Guadagni F Marzano R Iori F De Nunzio C Franco G Merola R Laurenti C 《Human pathology》2003,34(3):214-221
A systematic analysis of both tumors and the surrounding urothelium to help identify what lies behind the mechanism of multifocal tumor development has not yet been performed. In this study we investigated chromosome 1, 7, 9, and 17 aneusomy in 25 superficial papillary carcinomas and in 51 tissue samples taken from sites of macroscopically uninvolved urothelium surrounding the tumors, using the fluorescence in situ hybridization method. Our data demonstrated a close genetic relationship between all examined tumors and normal-appearing mucosa. Numeric aberrations of chromosomes 1, 7, 9, and 17 were found to exhibit similar patterns in all analyzed specimens, although with different frequencies. 相似文献