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PubMedDate not supplied

Aspects of ankylosing spondylarthritis immunopathogenesis correlated with some immunoseric- and synovial parameters in the investigation of histopathological and electronmicroscopic alterations of the articular cartilage correlated with some immunoseric and synovial parameters.

Eighteen biopsies of articular cartilage taken intraoperatory from patients with Ankylosing Spondylarthritis (AS) and from others with traumatisms (controls) were investigated using histopathological (HE, VG, PAS-Alcian, Gömöri, Safranin 0), electronmicroscopic and histoenzymamologic techniques. Histopathologically, the synovitis in AS is characterized by abundant synovia lymphoplasmocytic infiltrates associated with aspects of vascular hyperplasia and fibrosis. At the pannus synovia-cartilage junction we found the invasive synovia lymphoplasmocytic infiltrates. The proteoglycan (PG) depletion is confirmed histopathologically by diminishing the Safranin 0 staining, then ultrastructurally by the existence of collagen revealing areas, whereas biochemically, by the presence of glycosaminoglycans (GAG) in serum and synovial fluid (SF). The morphological data were related to some immunological parameters involved in pathogenesis. In this way, we found pathological values of the immune circulating complexes (ICC) (serum, mean = 73.5 U; SF mean = 81.80 U) and of anti Collagen II antibodies (serum mean = 410 U; SF mean = 436 U). The reactive protein C acting in the phase (CRP) showed high pathological values both in serum (mean = 5.01 mg%) and in SF (mean = 3.6 mg%) of the patients with AS, emphasizing the inflammatory characteristics of the rheumatic disease. The presence of ICC, anticollagen II antibodies and GAS as well in synovia suggests that the inflammatory articulation in AS is a local potential antigen of collagen and proteoglycan nature.

Cartilage, Articular↗
PubMed1976

[Cytodiagnosis of the uterine portio vaginalis according to WHO nomenclature. I. Correlative revision of cytological and histological diagnoses as quality control of selected materials. Frequency and possible reasons for the lack of correlation of cytological and histological diagnoses].

Smears from the uterine cervix have been evaluated for neoplastic changes on the basis of descriptive terms. The material was obtained by a single gynecologist using a standardized sampling technique and the results were compared with the respective histological diagnoses. Material which was found to be unsuitable for technical reasons was excluded from this study. A 98.7% agreement between cytological and histological findings was noted. Discrepancies between cytological and histological findings were essentially due to differing dysplastic changes in the deeper layers of the surface epithelium and the cervical glands, which were not sampled by the smears on the surface layer. In a few cases the discrepancies could not be explained but they disappeared after several years of observation. The practitioner should be acquainted with the nomenclature used by cytologists. In his turn, the cytologist should be familiar with the pathological anatomy of the organ in question.

Cell Biology↗
PubMed2000

Cross-correlation measures of unresolved multi-neuron recordings.

An increasing number of laboratories are studying population properties of the nervous system using data where the spike activity of more than one neuron is recorded on each electrode and where, accidentally or deliberately, these activities are not resolved into single unit spike trains. We have previously examined the consequences for measurement of cross-correlation between two such electrodes in the limited case where all individual distant (between electrode) correlations are the same and all individual close (on a single electrode) correlations are the same [Bedenbaugh, P.H., and Gerstein, G.L. (1997). Multiunit normalized cross correlation differs from the average single-unit normalized correlation. Neural Computation 9, 1265-1275]. Here, we lift these unrealistic restrictions to allow all values of individual correlation, and examine explicitly the cases of two or three unresolved neurons on each electrode. In these situations, the cross-correlation coefficient measured between the electrodes is a linear sum of the distant correlations, divided by a non-linear function of the close correlations. We then examine in detail the case of a single direct distant correlation and take account of all relevant indirect correlations. The measured interelectrode correlation shows a reduction of this actual distant correlation by a non-linear function of the close correlations on each electrode over most of their possible values. Finally, we examine the consequences of poor waveform sorting for correlation measures; here a supposedly isolated spike train is contaminated by some fraction of the activity of another train, a situation that unfortunately is all too common in experiments. All these distortions become far more serious in the more realistic situation of dynamic firing rates and correlations. This paper is intended as a cautionary note for those who want to draw inferences about neuronal organization and/or coding or representation by using cross-correlation analysis of unresolved recordings.

Animals↗
PubMed1988

Neural correlations in the dorsal cochlear nucleus: pairs of units with similar response properties.

1. Cross-correlation analysis of simultaneously recorded spike trains can be used to gain insight into functional interactions among neurons. In this paper, we report on cross-correlation analysis of neuron pairs in the dorsal cochlear nucleus (DCN) of the cat. Neuron pairs were isolated with two independent electrodes, which allow systematic study of the effects on correlation of distances between units and differences in their best frequencies (BFs). The data in this paper were obtained from 51 pairs consisting of two neurons of the same type. 2. Cross-correlograms were obtained for 35 pairs composed of type IV units, which are recorded from the principal cells of the DCN. Pairs of type IV units with correlated activities give cross-correlograms with increased correlation near zero delay. This feature is called a central mound (CM) and most likely results from shared excitatory or shared inhibitory inputs. 3. Records of spontaneous activity were obtained from 31 pairs of type IV units. Six of these pairs have correlated spontaneous activities. All six pairs have BFs that differ by less than 0.2 octaves. The shared input inducing these correlations must be a spontaneously active and tonotopically organized projection, like the auditory nerve. Type II units, thought to be DCN inhibitory interneurons that project to type IV units, are not spontaneously active, and thus cannot be the cause of correlated spontaneous activity. Similarly, cochlear granule cells, whose axons project orthogonally to the tonotopic sheets of DCN, cannot be the cause of correlated spontaneous activity because their projection is not confined tonotopically. 4. Stimulus-driven activities were studied for 12 type IV pairs that have uncorrelated spontaneous activities. Five of these pairs have correlated driven activities, with CMs whose sizes depend on the frequency and sound level of the acoustic stimulus. A frequency vs. sound level correlation response map shows the V-shaped tuning properties of the correlation-inducing mechanism. The properties of stimulus-driven correlation in these type IV pairs are consistent with the hypothesis that the correlation is induced by shared input from DCN type II units, although this is not the only possibility. 5. All six type IV pairs with correlated spontaneous activities have correlated driven activities. In five of these pairs, the degree of correlation decreases from its value with spontaneous activity when a low-level acoustic stimulus is applied. Three of these five pairs were tested at higher stimulus levels.(ABSTRACT TRUNCATED AT 400 WORDS)

Acoustic Stimulation↗