48 research outputs found

    Therapeutic Efficacy of Human Hepatocyte Transplantation in a SCID/uPA Mouse Model with Inducible Liver Disease

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    Severe Combined Immune Deficient (SCID)/Urokinase-type Plasminogen Activator (uPA) mice undergo liver failure and are useful hosts for the propagation of transplanted human hepatocytes (HH) which must compete with recipient-derived hepatocytes for replacement of the diseased liver parenchyma. While partial replacement by HH has proven useful for studies with Hepatitis C virus, complete replacement of SCID/uPA mouse liver by HH has never been achieved and limits the broader application of these mice for other areas of biomedical research. The herpes simplex virus type-1 thymidine kinase (HSVtk)/ganciclovir (GCV) system is a powerful tool for cell-specific ablation in transgenic animals. The aim of this study was to selectively eliminate murine-derived parenchymal liver cells from humanized SCID/uPA mouse liver in order to achieve mice with completely humanized liver parenchyma. Thus, we reproduced the HSVtk (vTK)/GCV system of hepatic failure in SCID/uPA mice.In vitro experiments demonstrated efficient killing of vTK expressing hepatoma cells after GCV treatment. For in vivo experiments, expression of vTK was targeted to the livers of FVB/N and SCID/uPA mice. Hepatic sensitivity to GCV was first established in FVB/N mice since these mice do not undergo liver failure inherent to SCID/uPA mice. Hepatic vTK expression was found to be an integral component of GCV-induced pathologic and biochemical alterations and caused death due to liver dysfunction in vTK transgenic FVB/N and non-transplanted SCID/uPA mice. In SCID/uPA mice with humanized liver, vTK/GCV caused death despite extensive replacement of the mouse liver parenchyma with HH (ranging from 32-87%). Surprisingly, vTK/GCV-dependent apoptosis and mitochondrial aberrations were also localized to bystander vTK-negative HH.Extensive replacement of mouse liver parenchyma by HH does not provide a secure therapeutic advantage against vTK/GCV-induced cytotoxicity targeted to residual mouse hepatocytes. Functional support by engrafted HH may be secured by strategies aimed at limiting this bystander effect

    Pros and cons for C4d as a biomarker

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    The introduction of C4d in daily clinical practice in the late nineties aroused an ever-increasing interest in the role of antibody-mediated mechanisms in allograft rejection. As a marker of classical complement activation, C4d made it possible to visualize the direct link between anti-donor antibodies and tissue injury at sites of antibody binding in a graft. With the expanding use of C4d worldwide several limitations of C4d were identified. For instance, in ABO-incompatible transplantations C4d is present in the majority of grafts but this seems to point at ‘graft accommodation’ rather than antibody-mediated rejection. C4d is now increasingly recognized as a potential biomarker in other fields where antibodies can cause tissue damage, such as systemic autoimmune diseases and pregnancy. In all these fields, C4d holds promise to detect patients at risk for the consequences of antibody-mediated disease. Moreover, the emergence of new therapeutics that block complement activation makes C4d a marker with potential to identify patients who may possibly benefit from these drugs. This review provides an overview of the past, present, and future perspectives of C4d as a biomarker, focusing on its use in solid organ transplantation and discussing its possible new roles in autoimmunity and pregnancy

    Electrolytes and Trace Elements in Human Breast Cyst Fluid

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    Gross cystic breast disease (GCBD) is one of the most common breast diseases, and women with apocrine (type I) cysts are at higher risk of developing breast cancer than women with flattened (type II) cysts. Type I cysts contain fluid with an electrolyte composition similar to that of intracellular fluid (Na/K ratio 3). The electrolyte composition of breast cyst fluid (BCF) has been investigated intensively; however, there have been only a few studies in literature reporting the content of trace elements in BCF. The aim of this study was to compare the concentrations of Na, K, Ca, P, Zn, Cu, Fe, and Na/K and trace element ratios in breast cyst fluid in two subgroups of breast cysts. Sixty-three BCF were obtained by needle aspiration from premenopausal women with GCBD diagnosed by clinical, xheromammographic, and cytological studies. After separation of cells for cytological evaluation, the cyst fluid was centrifuged and supernatant stored at -80A degrees C until the analysis. Sodium, potassium, calcium, phosphorus, and iron were measured using Roche Diagnostics commercial kits on Hitachi 747-200 autoanalyzer. Measurements of copper and zinc were performed by flame atomic absorption spectrophotometer on Shimadzu AAS 680. We found statistically significant higher K, lower Na, higher phosphorus concentrations, and lower Na/K ratios in type I cysts when compared with type II cysts' values. Median values of Na/K ratio in type I and in type II were 0.32 and 6.2, respectively. Higher Zn, Cu, and Fe concentrations with respect to median values were noted in type I cysts; higher [Na.Cu/K.Zn], [Na.Cu/K.Fe], and [Na.Zn/K.Fe] ratios were found in type II cysts. A significant negative correlation existed between Na/K and Cu, and a significant positive correlation between Na/K and Fe in type II cysts (r = -0.660, p = 0.007; r = 0.615, p = 0.014, respectively). We can conclude that the trace elements content of BCF, in addition to electrolytes, could be useful in classifying the breast cyst. Future studies in larger series are needed to confirm these data

    Cathepsin D and tenascin C expression in fibrohistiocytic tumors: An immunohistochemical analysis of 42 cases

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    Background: Cathepsin D (CatD) plays a significant proteolytic role in tumour invasion and metastasis. Tenascin C (Tn-C), a glycoprotein of the extracellular matrix, is involved in neoplastic growth, and its possible functions are related to cell adhesion and detachment. CatD and Tn-C have been widely studied in carcinomas. However, little is known about CatD and Tn-C distribution in mesenchymal tumors. The purpose of this study was to investigate the expression of CatD and Tn-C in fibrohistiocytic tumors Methods: A total of 42 fibrohistiocytic tumors- 24 dermatofibroma (DF), 6 dermatofibrosarcoma protuberans (DFSP), 12 malignant fibrous histiocytoma (MFH)- were studied. CatD and Tn-C expressions were evaluated by immunohistochemistry and scored semiquantitatively. Results: CatD overexpression was observed in 75% of MFH, 50% of DFSP and 20% of DF. CatD expression showed a statistically significant difference between DF and MFH (p=0.001). Stromal Tn-C expression was detected in 75% of DF and MFH and 83% of DFSP. Tn-C expression showed no significant difference among benign, intermediate malignancy, and malignant fibrohistiocytic tumors (p>0.05). Conclusions: CatD expression is found to be relatively higher in MFH and DFSP than DF and it may be a marker of malignancy in fibrohistiocytic tumors. Tn-C expression has no impact in the differential diagnosis of fibrohistiocytic tumors

    Glutamine administration enhances the healing of lung parenchymal injuries and reduces air leakage in rats

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    Beneficial effects of glutamine on wound healing are well known. Parenchymal injuries in the lung cause air leakage that resolves with wound healing. We aimed to determine the effect of glutamine on the healing of lung injuries. Wistar albino female rats were randomized in three groups. One group (control, n = 7) received intraperitoneal injection of 0.9% sodium chloride (1.5 ml/day), while other group (GLN, n = 7) received glutamine (1.5 g/kg/day), beginning two days prior to the operation for total four days. After thoracotomy, a lung parenchymal lesion was made with a scalpel in the right upper lobe. Only thoracotomy was performed to sham group (n = 4). Air leakage was observed in the isolated lungs of control group, but not GLN and sham groups, at 5 cm H2O of positive airway pressure (p < 0.001). The threshold of positive airway pressure for air leakage was 4.85 +/- 0.37 and 19.42 +/- 4.54 cm H2O for control and GLN groups, respectively (p < 0.001). For measurement of collagen content in the healing parenchyma, digital images were processed to calculate the stained area percentage (SAP). SAP for immature collagen, a marker for wound healing, was 0.36 +/- 0.18% and 1.48 +/- 0.83% (p = 0.02) in control and GLN groups, respectively, but no significant difference was noted in SAP for mature collagen. The grade of inflammation was not significantly different between control and GLN groups. We conclude that glutamine enhances lung parenchymal healing by increasing immature collagen secretion

    The relation of IgM deposition to clinical parameters and histomorphometry in childhood mesangial proliferative glomerulonephritis

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    We investigated the question of whether IgM deposition causes any difference in the histomorphometry of children with mesangial proliferative glomerulonephritis (MePGN)

    Anti-tumor necrosis factor-alpha-induced psoriasis.

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    We describe a patient with rheumatoid arthritis who developed psoriasis during treatment with etanercept; psoriatic lesions resolved completely after the drug was discontinued. but returned on rechallenge. No such adverse skin reaction occurred after switching therapy to infliximab. Through a Medline search we identified 11 reports involving 32 patients who developed psoriasis/psoriasiform eruptions during therapy with tumor necrosis factor-alpha (TNF-alpha) inhibitors. All TNF-alpha blocking agents have been reported to lead to or exacerbate psoriasis. In some cases skin changes were severe enough to discontinue the medication
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