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91.
Immunoassays for acidic ferritins rich in H subunits have shown that these isoferritins are predominant in some cells such as monocytes and red blood cells but have provided conflicting results about their presence in human serum. We have used an immunoradiometric assay based on a monoclonal antibody against human heart ferritin (monoclonal 2A4) for evaluating acidic ferritin concentration in human serum. This assay proved to be highly specific for acidic isoferritins having more than 60% H subunits. Heart-type ferritin was detected in only one fifth of normal sera and sera from patients with iron overload; values were very low compared with those for basic ferritin. Acidic ferritin was found in relatively high concentrations in most patients with iron deficiency anaemia. In other disease states characterized by increased serum concentrations of basic ferritin, acidic ferritin was always less than 21% of the total ferritin. Dialysis in low-ionic-strength buffer showed that both normal and pathological sera had binding factors for human heart ferritin. We conclude that: (i) human serum contains low concentrations of acidic isoferritins which, at variance with basic ferritin, do not appear to be directly related to the amount of storage iron; (ii) the findings of the present study reinforce the opinion that basic and acidic ferritins have different functional behaviours.  相似文献   
92.
Abstract: This paper reviews the genetic variants of alpha-1-antitrypsin (AAT) which have been sequenced with special emphasis on the s.c. deficiency variants. These result in AAT low plasma levels via three main mechanisms: 1) intracellular storage; 2) intracellular degradation; 3) lack of synthesis. Intracellular storage occurs with the classical Z variant and with a few variants called M-like, because of their isoelectric focusing (IF) pattern. The storage phenomen causes liver damage and can be demonstrated at both light and electron microscopic level with the help of immuno-histochemistry. We report a new deficiency variant of AAT (M-Cagliari) characterized by very low plasma levels, massive storage of AAT and liver cirrhosis. By using immunohistochemical techniques and DNA analysis we could demonstrate that M-Cagliari has antigenic and genetic properties other than the Z AAT.  相似文献   
93.
Haemoglobin synthesis was studied in bone marrow erythroblasts and in reticulocytes of 4 children with beta O-thalassaemia major and of 7 children with beta +-thalassaemia major. In patients with beta O-thalassaemia the gamma/a ratio was found to be lower in bone marrow than in peripheral blood. On the contrary, in patients with beta + thalassaemia the beta + gamma/a ratio was more balanced in bone marrow, where the beta-chain synthesis was higher, than in reticulocytes. This last result could be explained by the presence of an abnormal m-RNA for beta-chains in beta +-thalassaemia.  相似文献   
94.
Electrochemotherapy (ECT) is a novel treatment for recurrent or in-transit unresectable melanoma metastases based on the administration of anti-neoplastic drugs followed by cancer cell electroporation. Whether ECT can also induce anti-tumour immunity is unclear. We addressed this issue investigating the presence of dendritic cells (DCs) in the inflammatory infiltrate of ECT-treated lesions. Biopsies from melanoma patients (n = 9) were taken before ECT (T0), at d7 and d14 after treatment and studied by immunofluorescence with DCs-related antibodies. Epidermal Langerin+ Langerhans cells (LCs) were the most represented subset before treatment. ECT induced a significant reduction in epidermal LCs number at d7 (p < 0.001), while they were completely replaced at d14. Similarly, the few LCs observed intermingled with metastatic melanoma cells at T0 decreased after treatment (p < 0.001), suggesting an ECT-induced activation of LCs. Consistently, at d1 after ECT (n = 3 patients), LCs were found to express CCR7, which mediates LCs migration to regional lymph nodes, and CD83, the typical DCs maturation marker. In contrast, plasmacytoid DCs (pDCs) were not present at T0, but significantly increased after ECT both in melanoma metastasis (p < 0.001) and perilesionally (p < 0.05). Similarly, CD1c+ dermal DCs (dDCs), observed in low number before ECT, strongly increased at d7 and even more at d14 (p < 0.05 and p < 0.001, respectively). Notably, some dDCs expressed CD83. These data suggest that ECT promotes LCs migration from the tumour to draining lymph nodes and pDCs and dDCs recruitment at the site of the lesion. These findings may help to design new strategies of in situ DCs vaccination in cancer patients.  相似文献   
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In this work, we propose that for further studies of the physiopathology and treatment for inflammatory bowel diseases, an integral view of the conditions, including the triad of microbiota–heat shock proteins (HSPs)–probiotics, ought to be considered. Microbiota is the complex microbial flora that resides in the gut, affecting not only gut functions but also the health status of the whole body. Alteration in the microbiota’s composition has been implicated in a variety of pathological conditions (e.g., ulcerative colitis, UC), involving both gut and extra-intestinal tissues and organs. Some of these pathologies are also associated with an altered expression of HSPs (chaperones) and this is the reason why they may be considered chaperonopathies. Probiotics, which are live microorganisms able to restore the correct, healthy equilibrium of microbiota composition, can ameliorate symptoms in patients suffering from UC and modulate expression levels of HSPs. However, currently probiotic therapy follows ex-adiuvantibus criteria, i.e., treatments with beneficial effects but whose mechanism of action is unknown, which should be changed so the probiotics needed in each case are predetermined on the basis of the patient’s microbiota. Consequently, efforts are necessary to develop diagnostic tools for elucidating levels and distribution of HSPs and the microbiota composition (microbiota fingerprint) of each subject and, thus, guide specific probiotic therapy, tailored to meet the needs of the patient. Microbiota fingerprinting ought to include molecular biology techniques for sequencing highly conserved DNA, e.g., genes encoding 16S RNA, for species identification and, in addition, quantification of each relevant microbe.  相似文献   
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The aim of this study was to elucidate whether fecoflowmetry (FFM) could evaluate more detailed evacuative function than anorectal manometry by comparing between FFM or anorectal manometric findings and the clinical questionnaires and the types of surgical procedure in the patients who received anal-preserving surgery. Fifty-three patients who underwent anal-preserving surgery for low rectal cancer were enrolled. The relationships between FFM or the manometric findings and the clinical questionnaires and the types of procedure of anal-preserving surgery were evaluated. There were significant differences between FFM markers and the clinical questionnaire and the types of the surgical procedure, whereas no significant relationship was observed between the manometric findings and the clinical questionnaire and the types of the surgical procedure. FFM might be feasible and useful for the objective assessment of evacuative function and may be superior to manometry for patients undergoing anal-preserving surgery.Key words: Anorectal manometry, Anal-preserving surgery, Fecoflowmetry, Incontinence, Rectal cancerSphincter preservation has been one of the key issues of rectal cancer surgery. Low anterior resection (LAR)1 and internal and external sphincter resection (ISR and ESR) are anal-preserving surgeries.2,3 The aim of these procedures is to restore the normal process of defecation, along with its function, and to improve the quality of life of patients by avoiding permanent colostomy. However, anal-preserving surgery is often associated with evacuative dysfunction and various degrees of incontinence.47Most studies that have assessed the evacuation function have used clinical questionnaires, which are subjective and may vary according to the patient perception.7 There are many factors that can affect the evacuative function, such as the stool consistency, rectal capacity, anal sphincters, pelvic floor muscles, and intra-abdominal pressure. Although manometry with or without the clinical score has also commonly been used, fecoflowmetry (FFM) has been reported to be more accurate and useful for assessing the postoperative anorectal motor function.813 FFM was first introduced by Shafik and is a dynamic method for examining the anorectal motor activity that simulates the natural act of defecation.14 Some studies have shown its usefulness in postoperative patients with anorectal disease,811 but only a few studies have been performed to examine the evacuative function following anal-preserving surgery.12,13 The aim of this study was to evaluate the evacuative function in the postoperative period following anal-preserving surgery in patients with low rectal cancer using FFM, and to compare the results with the Wexner score and anorectal manometry.15  相似文献   
100.
It is now accepted from studies in animal models that hematopoieticstem cells emerge in the para-aortic mesoderm-derived aorta-gonad-mesonephros region of the vertebrate embryo. We have previously identified the equivalent primitive hematogenous territory in the 4- to 6-week human embryo, under the form ofCD34+CD45+Lin highproliferative potential hematopoietic cells clustered on the ventralendothelium of the aorta. To characterize molecules involved in initialstem cell emergence, we first investigated the expression in thatterritory of known early hematopoietic regulators. We herein show thataorta-associated CD34+ cells coexpress the tal-1/SCL,c-myb, GATA-2, GATA-3, c-kit, and flk-1/KDR genes, as do embryonic andfetal hematopoietic progenitors later present in the liver and bonemarrow. Next, CD34+CD45+ aorta-associatedcells were sorted by flow cytometry from a 5-week embryo and a cDNAlibrary was constructed therefrom. Differential screening of thatlibrary with total cDNA probes obtained from CD34+embryonic liver cells allowed the isolation of a kinase-related sequence previously identified in KG-1 cells. In addition to emerging blood stem cells, KG-1 kinase is also strikingly expressed in alldeveloping endothelial cells in the yolk sac and embryo, which suggestsits involvement in the genesis of both hematopoietic and vascular celllineages in humans.  相似文献   
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