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11.
A panel of neutralizing IgA monoclonal antibodies was produced from mice orally inoculated with poliovirus type 3 Sabin and cholera toxin as adjuvant. Low levels of neutralizing antibodies were elicited in mice after several boosts, but only in the presence of cholera toxin. Characterization of IgA MAbs by neutralization-escape virus mutants showed that all but one neutralizing MAbs against type 3 poliovirus were directed to antigenic site N-AgIII, which was previously found by us to be the major target of mucosal immune response to Sabin 1 in the mouse. Our data indicate that residue 236 of VP3, not previously reported, is also involved in forming site N-AgIII in addition to formerly described VP3 (aa 58-59) and VP1 (aa 286-290) residues. Unlike poliovirus type 1 IgA MAbs, all IgA MAbs herein described neutralized the wild-type parental poliovirus. 相似文献
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R Bernardini C E Fiore L Insirello M Pistritto V Costa G Clementi 《International journal of tissue reactions》1992,14(1):25-29
We have studied the effect of intravenous injection of eel calcitonin (ECT) on creatine kinase E.C.2.7.3.2. BB isozyme (CKBB) in the kidney of male Wistar rats. CKBB immunoreactivity was detected by the peroxidase-antiperoxidase method. Eel calcitonin increased CKBB immunoreactivity in the renal medulla in a dose-dependent fashion. Its effect peaked at 2 h and lasted up to 24 h. The distribution of activated CKBB in the kidney occurs in the same areas where highly specific CT-binding sites have been previously demonstrated, and is in agreement with the current concepts on renal actions of this hormone. 相似文献
14.
Oncocytic adencarcinoma of the rectum with diffuse intra-luminal microcalcifications: the first reported case 总被引:1,自引:0,他引:1
Piscitelli D Ingravallo G Resta L Fiore MG Maiorano E 《Virchows Archiv : an international journal of pathology》2003,443(4):579-582
Several histological variants of colorectal carcinoma have been reported, some of them bearing prognostic significance, others only incidental findings showing unusual morphological features. The current report was aimed to describe the histological, immunohistochemical and ultrastructural features of an oncocytic adenocarcinoma of the rectum occurring in a 66-year-old woman. Histologically, it was a moderately differentiated adenocarcinoma composed by glandular structures lined by eosinophilic cells. The latter showed abundant granular cytoplasm and large nuclei with prominent nucleoli. Several glandular structures contained intraluminal, basophilic and non-birifrangent microcalcifications. The tumour cells displayed consistent anti-mitochondrial antigen, carcinoembryonic antigen, p53, CDX2 and cytokeratin 20 immunoreactivity. Ultrastructurally, more than 80% of the cytoplasmic area was occupied by abnormal mitochondria, while exocrine or endocrine granules were undetectable. The tumour infiltrated the intestinal wall through the subserosal tissue, but lymph node or distant metastases were absent. The patient is disease free 22 months after surgery. Based on the above features, this case could be appropriately named oncocytic adenocarcinoma with intraluminal microcalcifications. Like gastric neoplasms showing similar morphologic features, this tumour might have a better prognosis, and the presence of microcalcifcations could help its proper recognition at a pre-operative stage. 相似文献
15.
INTRODUCTION: Osteosarcoma is a malignant bone neoplasm with an usually high metastatic potential. Besides the common metastatic sites such as lungs, bone, and pleura, metastases to unusual sites such as liver, brain and regional lymph nodes have also been reported with increasing frequency; among them, gastrointestinal metastases represent an extraordinarily rare event in the natural history of this neoplasia. MATERIALS AND METHODS: We describe a case of a 27 year old man, who was diagnosed with a grade IV osteoblastic osteosarcoma of the left tibia and submitted to 5 courses of pre-surgical chemotherapy; later he underwent tibial resection with implantation of a prosthesis, followed by 2 further courses of adjuvant chemotherapy. Five years after the patient presented with melena and acute anemia; during endoscopic examination, a large bleeding duodenal polyp was found, so a surgical resection of the gastric antrum, duodenum, head of the pancreas, main bile ducts and gallbladder was performed. The surgical specimen was formalin fixed and paraffin embedded, and sections obtained by the blocks were stained with haematoxylin-eosin; immunohistochemical and ultrastructural analysis were performed. RESULTS: Microscopically, the tumor mass showed a mostly fasciculated architecture, composed of spindle and epithelioid cells in a scarce fibromyxoid stroma, featuring large areas of coagulative necrosis and small foci of sclerohyalinosis. Tumor cells featured large vesciculous nuclei, with a few prominent nucleoli; no foci of osteoid matrix were detectable. The ultrastructural analysis revealed small calcified electron-dense depots both in the perinuclear cytoplasm and in the extracellular collagen matrix compatible with an "early osteoid formation". Due to alteration of the natural history of the tumor induced by multiagent chemotherapy, the rate of metastases of osteosarcoma to unusual sites has been increasing. We report the 9th case of a gastrointestinal metastasis of osteosarcoma reported thus far, and only the second one arising in the duodenum. Both the histological features and the immunohistochemical findings were not suggestive for osteosarcoma metastases because the tumor appeared dedifferentiated; in our case the combination of electron microscopy and clinical history played a pivotal role to establish the final diagnosis. 相似文献
16.
Seroprevalence of Kaposi's sarcoma-associated herpesvirus/human herpesvirus 8 in several regions of Italy 总被引:2,自引:0,他引:2
Calabrò ML Sheldon J Favero A Simpson GR Fiore JR Gomes E Angarano G Chieco-Bianchi L Schulz TF 《Journal of human virology》1998,1(3):207-213
OBJECTIVE: To study the seroprevalence of Kaposi's sarcoma-associated herpesvirus/human herpesvirus type 8 (KSHV/HHV-8) in 779 Italian blood donors. STUDY DESIGN/METHODS: Sera were tested for antibodies to a latency-associated nuclear antigen (LANA) and a capsid related protein encoded by ORF65. RESULTS: Among all Italian donors, 17.7% and 18.7% had antibodies to LANA and ORF65 protein, respectively, and 24.1% had antibodies to at least one antigen. KSHV/HHV-8 seroprevalence was higher in the Po valley and in Sardinia than close to the sub-Alpine Veneto region, Tuscany, or Apulia. KSHV/HHV-8 seroprevalence was almost equally distributed between men and women but increased in the older age groups. CONCLUSIONS: The regional differences and age distribution in seroprevalence agree partially with the incidence of classic KS in Italy. The rarity of classic KS in KSHV/HHV-8-infected subjects and the equal gender distribution of seroprevalence suggest that other cofactors may contribute to KS development in human immunodeficiency virus type 1 (HIV-1)-uninfected individuals. 相似文献
17.
18.
M. Fiore C. Pera L. Delfino I. Scotese G. B. Ferrara C. Pignata 《International journal of immunogenetics》1995,22(5):403-411
IgA deficiency (IgA-D) represents the most common immunodeficiency syndrome of infancy. In most cases IgA-D represents an isolated immunological disorder, while sometimes it is associated with IgG subclass deficiency or with the presence of autoantibodies. We investigated the pattern of association of IgA-D with DRB1 and DQB1 loci of the HLA region by DNA molecular typing, which allows the identification of previously serologically undefined specificities. We also compared the gene frequency of DRB1 and DQB1 allelic variants between IgA-D subjects with or without serum autoantibodies. Our results indicate that the gene frequency of the DRB1*0102 subtype and of the DRBP0102, DQB1*0501 haplotype is significantly higher in IgA-D than in the general population. Furthermore, the IgA-D subjects with autoantibodies showed a positive association with DR4 and DR13 subtypes, thus supporting the hypothesis that genetic factors are also involved in the association between IgA-D and autoantibodies. 相似文献
19.
P Conti M Reale R C Barbacane M R Panara M Bongrazio S Fiore J W Mier R A Dempsey 《Immunology letters》1992,32(1):71-79
Polymorphonuclear leukocytes (PMN) are known to be activated by several lymphokines and can be induced to release lysosomal enzymes, prostaglandins (PG), thromboxanes (TX) and lipoxygenase products that may be involved in PMN aggregation responses during inflammatory reactions. Granulocyte-macrophage colony stimulating factor (GM-CSF), a glycoprotein cytokine released by immunocompetent cells, has been found to prime neutrophil responses, such as increased cell aggregation after exposure to various biological stimulants. In this study, we examined the effects of the cytokine GM-CSF on human neutrophilic aggregation stimulated by N-formyl-methionyl-leucyl-phenylalanine (FMLP) and its influence on the production of various arachidonic acid metabolites. Neutrophil aggregation of purified PMNs was measured by the percent change in light transmission in a standard aggregometer, and the arachidonic acid products leukotriene B4 (LTB4) and thromboxane A2 (TXA2) were quantified by radioimmunoassay. We found that GM-CSF and other cytokines, used alone, did not cause any significant increase in aggregation of the PMN. However, prior exposure of PMN to GM-CSF markedly increased the aggregation induced by FMLP as opposed to that detected with PMN stimulated with only FMLP. This priming effect was not observed with PMN preincubated with interleukin-1 (IL-1), tumor necrosis factor (TNF) or interleukin-6 (IL-6). In addition, GM-CSF and IL-6 both failed to stimulate the production of LTB4 and TXA2, products which are known to induce PMN aggregation. These findings provide new evidence suggesting that GM-CSF facilitates the action of FMLP on the adhesion dependent cellular functions of the inflammatory response, serving as an important co-factor in neutrophil aggregation. 相似文献
20.
Fausto Biancari Giovanni Mariscalco Magnus Dalén Nicla Settembre Henryk Welp Andrea Perrotti Karsten Wiebe Enrico Leo Antonio Loforte Sidney Chocron Davide Pacini Tatu Juvonen L. Mikael Broman Dario Di Perna Hakeem Yusuff Chris Harvey Nicolas Mongardon Juan P. Maureira Antonio Fiore 《Journal of cardiothoracic and vascular anesthesia》2021,35(7):1999-2006