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排序方式: 共有5482条查询结果,搜索用时 15 毫秒
1.
Anna Maria Lavezzi Giulia Ottaviani Lorella Terni Luigi Matturri 《International journal of developmental neuroscience》2006,24(6):365-371
The aim of this study was to investigate the histological and biological features of the human cerebellar cortex development and differentiation. We analyzed 52 brains of fetal and infant death victims, aged from 17 gestational weeks to 12th postnatal month. In particular, in the cerebellar cortex at different ages we evaluated, besides the structural aspects, the expression of several biomarkers implicated in proliferative processes (c-fos, PCNA and apoptosis). We observed morphological patterns progressively evolving every month, from the indefinite structure of the second gestational trimester to the four-layered structure (external granular layer, molecular layer, Purkinje cell layer, internal granular layer) of the late fetal cortex and subsequently to the three-layered postnatal definitive morphology, due to involution of the external granular layer. The evaluation of the biological features of the cerebellar cortex showed high proliferative activity mainly confined to the transient external granular layer in prenatal life, and high apoptotic index after birth. Thus, the histological examination, better with the support of biomarker investigations, allows with accuracy to describe the dynamic sequence of steps that occur in human cerebellar cortex development and to establish in each case the age, namely the pre- or postnatal month of life. Consequently, we can diagnose delayed or altered processes of differentiation during the development of the human cerebellar cortex. 相似文献
2.
Pelosi G Scarpa A Veronesi G Spaggiari L Del Curto B Moore PS Maisonneuve P Sonzogni A Masullo M Viale G 《Virchows Archiv : an international journal of pathology》2005,447(6):969-977
Nuclear translocation of β-catenin has been correlated with epidermal growth factor receptor (EGFR) overexpression/activation
in nonsmall cell lung cancer. Less is known on β-catenin transactivation in high-grade pulmonary neuroendocrine tumors and
on the status of β-catenin activating EGFR and human epidermal growth factor receptor 2 (HER-2) or β-catenin target genes
cyclin D1 and matrix metalloproteinase-7 (MMP-7). β-catenin immunoreactivity was evaluated in 51 large-cell neuroendocrine
carcinomas (LCNEC) and 45 small-cell lung carcinomas (SCLC). Nineteen cases were assessed for β-catenin gene exon 3 mutations, expression of MMP-7, and expression/gene amplification of EGFR, HER-2, and cyclin D1. β-catenin was
expressed in all 96 high-grade neuroendocrine tumors, the vast majority (94%) showing >50% immunopositive cells. A disarrayed
immunoreactivity, however, was commonly encountered consisting in variably altered membrane-associated patterns of staining
along with progressive accumulation of cytoplasmic immunoreactivity. In LCNEC, but not in SCLC, the disarrayed patterns correlated
with EGFR and HER-2 protein expression. β-catenin nuclear accumulation was found in nine tumors, including seven LCNEC and
two SCLC, and was always associated with disarrayed immunoreactivity and increased MMP-7, but not cyclin D1 expression. These
cases, however, did not show β-catenin gene mutations or EGFR and HER-2 gene amplification or expression. No association was found between nuclear β-catenin and
any clinicopathological variable including patients' survival. The subcellular compartmentalization of β-catenin is profoundly
altered in high-grade pulmonary neuroendocrine tumors. A minor subset of these tumors shows β-catenin nuclear accumulation
in association with increased expression of MMP-7, but not of cyclin D1, independent of EGFR and HER-2 gene amplification
or expression.
The authors have no significant financial or other relationship with the manufacturers of any commercial products or commercial
services presented in this paper 相似文献
3.
Federica Cavallo Alfonso Martin-Fontecha Matteo Bellone Silvia Heltai Evelina Gatti Paola Tornaghi Massimo Freschi Guido Forni Paolo Dellabona Giulia Casorati 《European journal of immunology》1995,25(5):1154-1162
Although the transfection of B7-1 cDNA into a few mouse tumor cell lines can induce anti-tumor T cell immunity, its expression alone is ineffective in many other tumor cell lines tested. We were interested to study what factors limit B7-1 co-stimulatory activity, and decided to investigate whether B7-1 requires the cooperation of ICAM-1 to provide the minimal co-stimulatory signal for establishing an efficient anti-tumor immunity. We show that the transfection of B7-1 cDNA into three ICAM-1+ (plasmocytoma J558L, T lymphomas EL-4 and RMA), but not into two ICAM-1? tumor cell lines (adenocarcinoma TS/A and melanoma B16.F1), is sufficient to induce their complete rejection in syngeneic mice. The expression of ICAM-1 is necessary for the rejection of the B7 expressing tumors, since the primary response elicited by B7-1+ EL-4 and RMA clones expressing reduced levels of ICAM-1 is severely reduced. Furthermore, super-transfection of ICAM-1 cDNA into B7-1+ adenocarcinoma and melanoma clones optimizes their primary rejection. Histologic examination of transfected tumors reveals that B7-1 and ICAM-1 exert a potent pro-inflammatory activity. The intra-tumor infiltration is composed of both eosinophils and lymphomono-cytes, and is already massive 5 days after the tumor challenge. The primary rejection of the B7-1+ ICAM-1+ tumors depends critically on CD8+ T cells, natural killer cells and granulocytes, but is independent of CD4+ T cells. Remarkably, in addition to its effects on the early phases of the immune response, the co-expression of ICAM-1 and B7-1 on tumors is also necessary for the efficient induction of a memory response. In fact, only the primary challenge with B7-1+, ICAM-1+ tumor cells protects the majority of the mice from a second injection of parental tumor cells. Collectively, our findings indicate that B7-1 and ICAM-1 are fundamental components for triggering the primary rejection of tumors and establishing a protective memory response. These findings may help to define new strategies for the rational application of co-stimulation in tumor immunotherapy. 相似文献
4.
di Gioia CR Ciallella C d'Amati G Parroni E Nardone AM Gallo P 《Archives of pathology & laboratory medicine》2003,127(9):e367-e370
An infant with normal facies and none of the extracardiac anomalies usually associated with Williams syndrome presented at birth with an echocardiographic pattern of supravalvular pulmonary stenosis and displastic pulmonary valve. A clinical reappraisal was planned at 3 months of age, but the girl died suddenly at home at 2 months of age. At autopsy, both ventricles were hypertrophic, and the valves showed mild dysplasia. The walls of the great arteries were thick, with a "washed leather" consistency, but there was no gross evidence of discrete stenosis. The histologic mosaic appearance of the media of the great arteries, due to elastosis and extreme disarray of the elastic lamellae, prompted a postmortem diagnosis of supravalvar aortic stenosis and suggested a diagnosis of Williams syndrome, which was subsequently confirmed by fluorescence in situ hybridization. Pediatricians and pathologists should be alerted that Williams syndrome in the newborn may present as an isolated supravalvular pulmonary stenosis, whereas supravalvular aortic stenosis becomes clinically significant only a few months later. 相似文献
5.
d'Amati G Bagattin A Bauce B Rampazzo A Autore C Basso C King K Romeo MD Gallo P Thiene G Danieli GA Nava A 《Human pathology》2005,36(7):761-767
We report on a family with a history of sudden death and effort-induced polymorphic ventricular arrhythmias. The index case was a 17-year-old boy who died suddenly and at postmortem had evidence of fibrofatty replacement in the right ventricular free wall, consistent with arrhythmogenic right ventricular cardiomyopathy, as well as calcium phosphate deposits within the myocytes. A molecular genetics investigation carried out in the paraffin-embedded myocardium of the subject and in blood samples of family members disclosed a missense mutation in exon 3 (230C-->T; A77V) of the cardiac ryanodine receptor type 2 gene. The carriers showed effort-induced polymorphic ventricular tachycardia in the setting of normal resting electrocardiogram and trivial echocardiographic abnormalities, consistent with catecholaminergic polymorphic ventricular tachycardia. The observation of both arrhythmogenic right ventricular cardiomyopathy type 2 and catecholaminergic polymorphic ventricular tachycardia in the same family suggests that the two entities might correspond to different degrees of phenotypic expression of the same disease. This experience underscores the importance of a precise autopsy diagnosis in the case of sudden cardiac death, including molecular genetics, and the mission of pathologists to guide further clinical investigation of family members. 相似文献
6.
Giulia Barcia Marlne Rio Zahra Assouline Coralie Zangarelli Charles-Joris Roux Pascale de Lonlay Julie Steffann Isabelle Desguerre Arnold Munnich Jean-Paul Bonnefont Nathalie Boddaert Agns Rtig Metodi D. Metodiev Benedetta Ruzzenente 《European journal of human genetics : EJHG》2021,29(3):533
Mitochondrial translation is essential for the biogenesis of the mitochondrial oxidative phosphorylation system (OXPHOS) that synthesizes the bulk of ATP for the cell. Hypomorphic and loss-of-function variants in either mitochondrial DNA or in nuclear genes that encode mitochondrial translation factors can result in impaired OXPHOS biogenesis and mitochondrial diseases with variable clinical presentations. Compound heterozygous or homozygous missense and frameshift variants in the FARS2 gene, that encodes the mitochondrial phenylalanyl-tRNA synthetase, are commonly linked to either early-onset epileptic mitochondrial encephalopathy or spastic paraplegia. Here, we expand the genetic spectrum of FARS2-linked disease with three patients carrying novel compound heterozygous variants in the FARS2 gene and presenting with spastic tetraparesis, axial hypotonia and myoclonic epilepsy in two cases.Subject terms: Metabolic disorders, Mutation 相似文献
7.
Expression of human CD81 in transgenic mice does not confer susceptibility to hepatitis C virus infection 总被引:6,自引:0,他引:6
Masciopinto F Freer G Burgio VL Levy S Galli-Stampino L Bendinelli M Houghton M Abrignani S Uematsu Y 《Virology》2002,304(2):187-196
We previously demonstrated that hepatitis C virus (HCV) binds to human CD81 through the E2 glycoprotein. Therefore, expression of the human CD81 molecule in transgenic mice was expected to provide a new tool to study HCV infection in vivo, as the chimpanzee is the only species currently available as a laboratory animal model that can be infected with HCV. We produced transgenic mice expressing the human CD81 protein in a wide variety of tissues. We confirmed binding of recombinant E2 glycoprotein to the liver tissue as well as to thymocytes and splenic lymphocytes in the transgenic mice. We inoculated chimpanzee plasma infected with HCV into these animals. None of these transgenic animals showed evidence of viral replication. Furthermore, human CD81 transgenic mice that lack expression of endogenous mouse CD81 were also resistant to HCV infection. We conclude that expression of human CD81 alone is insufficient to confer susceptibility to HCV infection in the mouse. The presence of additional possible factors for HCV infection is discussed. 相似文献
8.
Michele Guida Addolorata Casamassima Giulia Monticelli Michele Quaranta Giuseppe Colucci 《Journal of translational medicine》2007,5(1):51
Background and purpose
Metastatic renal cell carcinoma (MRCC) has a poor prognosis with a median overall survival of about one year. Since only a minority of patients experienced therapeutic benefit to current treatments, several studies have attempted to identify factors that may have an impact on response and survival. Cytokines play a crucial role in the host's immune response by regulating the development and function of a lot of biological compartments. Nevertheless, available data on basal cytokine levels in MRCC are very few and no clear profile of serum cytokines has been identified yet in these patients population. Thus, determining the levels of cytokines in MRCC could not only help in understanding the biological mechanisms of the tumor growth, but also in evaluating if different cytokine profiles are correlated with particular clinical behaviors. 相似文献9.
Matturri L Ottaviani G Lavezzi AM 《Virchows Archiv : an international journal of pathology》2005,447(1):74-80
Cigarette smoking is associated with an increased incidence of atherosclerotic diseases. The aim of this study was to examine the progression of the preatherosclerotic lesions previously observed by us in coronary arteries of fetuses of smoker mothers and in infants with smoker parents. We examined the coronary arteries of 34 infants, aged 1–36 months, and the histological and biological [c-fos, proliferating cell nuclear antigen (PCNA), and apoptosis] features of the early atherosclerotic lesions. In 17 infants (50%), at least one parent smoked, generally more than five cigarettes a day. In 18 cases (53%), we observed variable thickening of the coronary walls from preatherosclerotic lesions to juvenile atherosclerotic plaques, related to parental smoking habit. This morphological progression of the lesions was accompanied by a sequence of biological changes in the smooth muscle cells of the tunica media. We suggest that the oxidants present in the gas phase of the parental cigarette smoke pass through the endothelium and induce at first the c-fos gene activation and subsequently the PCNA positivity, that is, a proliferative process. 相似文献
10.
We analyzed the early stages of reactivity of three different particle size samples of Bioglass 45S5 and a bulk sample in TRIS-buffered solution at pH 8. Ion release, measured with ion-coupled plasma emission spectroscopy, and pH variations are reported. It was demonstrated that differences in the initial surface area influence the increase in pH, the rate of elemental release, and the rate of calcium phosphate reprecipitation. In particular, a thicker Ca/P layer was obtained on larger particles. The equilibrium value of Si in solution was independent of sample form and amount of sample dissolved, and was always close to the value observed when bulk silica is dissolved at pH 8. An analytical model is proposed for cation release, based on a two-step mechanism. It was found that the early stage of dissolution was nearly diffusion controlled for larger particles and bulk samples. The second stage was similar to a first-order homogeneous dissolution. The influence of sample surface area/solution volume ratio seemed to be more complex than that proposed in the early works presented in the literature. It is suggested that variation of surface area has a significant impact on the course of the dissolution. 相似文献