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41.
B R Broxup V E Valli G L Losos D H Percy E Farber I McMillan 《Toxicologic pathology》1988,16(4):401-417
Classification of rat hepatocellular proliferative lesions can vary between pathologists as the many qualitative histologic criteria have not been satisfactorily evaluated and ranked for prognostic value. Computer-assisted morphometry offers an objective method to evaluate certain cellular features. The Solt-Farber resistant hepatocyte model was used in this study to produce populations of rats with a full range of hepatocellular proliferative lesions. Cellular features within the lesions were then measured morphometrically and the data were analyzed by animal age and by subjective lesion diagnosis. The nuclear/cytoplasmic ratio followed by the cell area and nuclear area were found to be the most important parameters for separating microscopic foci and islands of cellular alteration, an early hyperplastic lesion, from other hepatocellular proliferative lesions. The coefficient of variation, as a relative measure of heterogeneity, increased in a linear manner for cell, nuclear and nucleolar areas as the animals aged and was significantly higher for cell and nuclear area in hepatocellular carcinoma compared to other hepatocellular proliferative lesions. Hepatocyte nodules (representing primarily late hyperplastic lesions) and persistent hepatocyte nodules (lesions with similarities to hepatocellular adenoma) could not be satisfactorily separated within the limits of this study. As these borderline lesions show a continuum of cytologic change, other features, such as architectural change, are necessary to satisfactorily classify them on a subjective basis. An alternative approach is to use discriminant functions derived from morphometric studies. 相似文献
42.
Ghrelin expression in hyperplastic and neoplastic proliferations of the enterochromaffin-like (ECL) cells 总被引:1,自引:0,他引:1
Ghrelin, a recently discovered peptide isolated from the gastric corpus mucosa, is believed to be important in the regulation
of growth hormone secretion and has been shown to increase appetite and food intake as well. It may also have other gastrointestinal
and cardiac functions. Because a cell of origin for ghrelin has not been convincingly identified in the gastric mucosa thus
far, we studied the immunohistochemical expression of ghrelin in proliferative lesions of the enterochromaffin-like (ECL)
cells—a cell that is not only exclusively confined to the gastric corpus mucosa but is its dominant endocrine cell type as
well.
Formalin-fixed, paraffin embedded tissues from three cases of gastric ECL cell hyperplasia and five ECL carcinoids (three
with coexisting foci of diffuse, linear, and micronodular hyperplasia) were immunohistochemically stained for ghrelin, using
a commercially available antibody. The Sevier-Munger stain for ECL cells and immunohistochemical stains for chromogranin,
gastrin, serotonin, somatostatin, and vesicular monoamine transporter-2 (VMAT-2) were performed on parallel sections for correlation
with the ghrelin staining results.
All ECL cell carcinoids and hyperplastic lesions were positive for both the Sevier-Munger and the immunohistochemical stains
for chromogranin and VMAT-2. Immunoreactivity for ghrelin was seen in 4/5 ECL carcinoids, all cases of ECL cell hyperplasia,
as well as in all areas with linear and micronodular hyperplasia adjacent to the ECL cell carcinoids. In each instance, such
staining was confined to the Sevier-Munger, and VMAT-2 positive cells only.
Our findings indicate that the ECL cells are either the ghrelin-producing cells of the gastric mucosa or acquire the capability
to synthesize ghrelin during proliferative states encompassing the entire hyperplasia to neoplasia spectrum. In view of the
orexigenic and other known actions of ghrelin, the functional and/or biologic significance of ghrelin production in such ECL
cell proliferations needs to be investigated further. 相似文献
43.
Paul S. Thorner Reuben Baumal Victor E. O. Valli Don Mahuran Paula M. Marrano Robert Jacobs 《Virchows Archiv : an international journal of pathology》1992,421(6):467-475
Summary Some patients with hereditary nephritis (HN) who have received a renal transplant have been shown to form antibody with specificity for the NC1 domain of collagen type IV, a major constituent of glomerular basement membranes (GBM). We attempted to duplicate this phenomenon in a family of dogs with X-linked HN, a model for human X-linked HN, by immunizing affected male dogs with normal dog NC1 domain. A collagenase digest was prepared from normal dog GBM, the NC1 domain was separated into dimer (50 kDa) and monomer (24 kDa and 26 kDa) components by SDS-PAGE, and injected into two affected male dogs. Antisera obtained from both dogs contained antibody which reacted with the NC1 domain of dog and human GBM by a plate-binding radioimmunoassay, bound to the dimer and 26 kDa monomer bands by Western blotting, and staining dog and human GBM by immunofluorescence (IF). The affected male dog antiserum reacted equally by radioimmunoassay with the NC1 domain isolated from GBM of unaffected, affected male, and carrier female dogs in the family with X-linked HN, and bound by Western blotting to dimers and the 26 kDa monomer band of the NC1 domain of GBM in each group of dogs. However, the affected male dog antiserum differentiated these dogs by IF; it produced global staining of GBM of unaffected dogs, failed to stain GBM of affected male dogs, and produced segmental staining of GBM of carrier female dogs. Absorption of the affected male dog antiserum with normal dog NC1 domain eliminated the staining of dog GBM by IF, whereas staining persisted after absorption with affected male dog NC1 domain. The abnormal staining patterns of GBM seen by IF in the affected male and carrier female dogs and the results of the absorption studies imply an abnormality of one or more determinants in the 26 kDa monomer band of the NC1 domain of their GBM. Amino acid sequencing of this band identified the 1(IV) chain of collagen type IV, a finding that has implications for the pathogenesis of canine X-linked HN. Absent and segmental staining respectively were also seen by IF in GBM of a male and female patient with HN, using the affected male dog antiserum. Thus, the results obtained in affected male and carrier female dogs with X-linked HN may also be relevant to patients with this disease. 相似文献
44.
Haseeb Ahsan 《Journal of immunoassay & immunochemistry》2019,40(1):91-108
ABSTRACTMany ingredients in cosmetic products help to develop complex formulations that improve the quality of life in terms of disease prevention, health maintenance, beauty enhancement, and building self-esteem. The beneficial effects promoted from the use of biomolecule-rich substances into the formulations of various topical application products are considered useful ingredients in cosmetic and therapeutic applications. This review article attempts to understand the various biomolecules found in cosmetic products, particularly macromolecules, which may have an important role in prevention or preservation. Increasing demand of cosmetics all over the world has increased the awareness related to safety issue. Cosmetic products may contain potential contact allergens or precursors that can be oxidized or metabolized to generate contact allergens which can potentially cause allergic reactions or dermatitis. These substances can pose hazards to human health due to their ability to activate T cells that can cause allergic contact dermatitis, an inflammatory skin disease. Finally, the simultaneous on-site measurement of different substances from a single sample, called multiplexed point-of-care testing, has recently become increasingly important for the in vitro quantification of pathological or toxicological samples. Hence, the technological advancements in clinical sciences will be helpful in the identification of ingredients in cosmetic preparations. 相似文献
45.
Two patients affected with two different forms of Osteogenesis Imperfecta were examined in order to study collagen and glycosaminoglycans (GAGs) in skin and iliac crest cartilage. A sharp decrease of the galactosamine to glucosamine ratio due to a reduced content of chondroitin sulfate was evidenced in both patients. Moreover the structure of proteoglycans appeared altered, this being more evident in the severe form of the disease. Morphological examination in light and electron microscopy of cartilage of the less severely diseased patient showed that GAGs in the extracellular matrix did not present regular connection with collagen fibers. Chondrocytes, elongated and disorderly scattered, showed large lipidic inclusions and, on histochemical basis, were devoid of UDPG dehydrogenase activity. Treatment with (+)-catechin produced an improvement, in both patients, of the biochemical pattern of collagen and GAGs. Similarly a shift of the cellular activity and of the matrix morphology towards normality was observed in the investigated cartilage of the less severely affected patient. 相似文献
46.
47.
Haseeb Khan Ahmad Saleh Al Deeb Khalaf Al Moutaery Mohammad Tariq 《Experimental and toxicologic pathology》2003,55(2-3):181-186
A direct association between aging and drug-induced dyskinesia has been reported by several investigators. Iminiodipropionitrile (IDPN), a prototype nitrile compound produces a motor syndrome in rodents, which resembles neuroleptic drug induced dyskinesia. In this investigation attempt has been made to study the effect of age on IDPN induced vestibular hair cell degeneration and resulting dyskinetic syndrome. Male Wistar rats aged 3, 6 and 12 weeks received IDPN in the doses of 0, 200 and 400 mg/kg, intraperitoneally for 3 consecutive days. IDPN-induced dyskinesia was assessed using a behavioral testing battery on days 3, 4, 5, 6, 7, 14, 21 and 28. The rats were sacrificed on day 28; temporal bones were excised for vestibular histopathology and sera were collected for measuring the indices of oxidative stress (glutathione and conjugated dienes). IDPN in the dose of 200 mg/kg produced dyskinesia in 12 weeks old rats, but failed to do so in 3 and 6 weeks old rats. The high dose of IDPN (400 mg/kg) caused dyskinesia in all age groups, however, its onset and severity were age-dependent. Older rats showed an early onset and significantly high incidence of dyskinesia as compared to younger rats. The susceptibility of rats to IDPN-induced behavioral deficits was proportional to oxidative stress and degeneration of sensory hair cells in the crista ampullaris. 相似文献
48.
R Arnaud-Castiglioni T Bougerol H Chakroun L Cornu M Valli F Warnery E Louvel P Carayon J C Scotto 《L'Encéphale》1985,11(6):267-271
In the present study, clinical interview, Visual Evoked Potentials, psychological tests, TRH test, plasmatic MHPG dosage were investigated in 30 depressed patients with major depressive disorders. All the explorations were realised before and after 28 days of an antidepressant treatment. Thanks to analysis we found out the value of psychological tests. The study of evoked potentials brings to light the existence of electrophysiological variables, subordinate to the clinical state. On the contrary, "TRH Test" does not give us any useful indication, and plasmatic MOPEG dosage, although it confirms the existence of two groups of depressed patients, does not suggest any relationship with evolutive types. 相似文献
49.
Arterial hypertension associated with the use of a tourniquet with either general or regional anaesthesia 总被引:2,自引:0,他引:2
H. Valli P. H. Rosenberg J. Kytta M. Nurminen 《Acta anaesthesiologica Scandinavica》1987,31(4):279-283
A hypertensive patient with left cardiac enlargement developed marked hypertension under general anaesthesia, during which time a tourniquet was applied around his thigh. When the tourniquet was released, severe hypotension ensued which responded to therapy. The patient, however, died 16 h later of a myocardial infarction. Because of this incident, the anaesthetic and haemodynamic data of 699 patients who underwent limb surgery with a pneumatic tourniquet inflated for at least an hour were retrospectively examined using multivariate analysis. A 30% increase in systolic and/or diastolic arterial blood pressure occurred in 27% of the total patient material and in 67% of those who had had a general anaesthetic. There was a higher frequency of the occurrence of "tourniquet hypertension" with older age, longer operations and the operation site being the lower rather than the upper limb. Tourniquet hypertension rarely occurred in patients with spinal anaesthesia (2.7%) and brachial plexus blockade (2.5%), while those with intravenous regional anesthesia had a higher incidence (19%) of hypertension. 相似文献
50.
While quality measures are integral to the maintenance of a high standard of patient care, high-quality care remains a complicated concept to define in the context of acute care. In this article we explore how quality can be measured in the intensive care unit. Standard outcome metrics such as mortality are tangible comparators, but do not offer a comprehensive assessment of quality for the complex heterogeneity of the intensive care population. We explore the Donabedian model as a means to describe the importance of outcomes, processes, structure and environment to inform the measurement of quality. These concepts can be more abstract and difficult to measure but can provide significant insight into the culture of a unit and the resulting performance, and thus provide a more comprehensive measure of quality. 相似文献