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51.
A technique for the rapid detection of cytomegalovirus (CMV) antigen-positive blood leucocytes (CMV antigenaemia) was evaluated in 15 marrow transplant patients as a means of diagnosis and for monitoring CMV-associated disease. CMV antigenaemia was determined by direct immunoperoxidase staining of leucocytes with a peroxidase-labelled monoclonal antibody, HRP-C7, which binds an immediate-early antigen of human CMV.
CMV antigenaemia occurred in 7/15 marrow transplant patients (47%) and was initially detected between 4 and 6 weeks after transplantation. CMV-associated diseases developed in 3/15 patients (20%). All patients with CMV-associated disease had a relatively large number of CMV antigen-positive leucocytes, exceeding 10 per 50000 white blood cells (WBCs). In the remaining 12 patients, CMV antigen-positive leucocytes were less than 10 per 50000 WBCs or were undetectable. CMV-associated disease did not develop in these patients during the period of monitoring. CMV antigen-positive leucocytes were detected more frequently in patients who developed acute graft-versus-host disease (GVHD) or haemorrhagic cystitis than in those without such complications. CMV antigens were detectable from 1 to 4 weeks before the onset of CMV-associated disease which allowed initiation of ganciclovir treatment at an early stage. The degree of CMV antigenaemia paralleled the clinical symptoms and signs, higher degrees of antigenaemia being associated with more significant disease. Thus, the detection of CMV antigen-positive blood leucocytes is useful for the diagnosis and monitoring of CMV-associated disease following bone marrow transplantation.  相似文献   
52.

Objective

The characteristic pathological muscular findings of polymyositis (PM) and dermatomyositis (DM) have been shown to reflect their different pathogeneses. Here, we characterized the muscle biopsy findings of PM and DM patients with or without malignancy.

Methods

We evaluated the muscle biopsy findings of 215 consecutive PM and DM patients admitted to our hospital between 1970 and 2009. Pathology of the lesion biopsy sections was classified into 3 types: endomysial infiltration-type, perivascular infiltration-type, and rare-infiltrative-type.

Results

There was no difference between the muscle pathology of PM patients with and without malignancy. However, the incidence of rare-infiltrative type muscle pathology in DM patients with malignancy was significantly higher than in those without such tumors (p = 0.0345).

Conclusion

The incidence of rare-infiltrative type muscle pathology may be a predictive marker of DM with malignancy.  相似文献   
53.
54.

Background  

Maharishi Amrit Kalash (MAK) 5, one of the Ayurvedic food supplements, belongs to a group of substances known as Rasayana. MAK5 and other Rasayanas are believed to enhance the body's resistance to infections and disease, and enhance longevity. In this study, we determined the effects of administration of MAK5, one of the Ayurvedic food supplements on immune functions in young and old mice.  相似文献   
55.
The aim of this study was to investigate cell kinetics and ultrastructural changes during carcinogenesis using a hamster 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced tongue cancer model. Five squamous cell carcinomas, five dysplastic epithelia, seven hyperplastic epithelia, and four normal epithelia were obtained from 21 hamster tongues by applying 1.0% acetone solution of DMBA on the left lingual mucosa after scratching with a root canal broach. Ultrastructural examination revealed that the number of microvilli increased, whereas that of desmosomes decreased during carcinogenesis. Cell proliferation was analyzed by means of 5-bromodeoxyuridine (BrdU) immunohistochemistry and in situ hybridization (ISH) for histone H3 mRNA. The BrdU and histone H3 mRNA labeling indices (LIs) were lowest for normal epithelium, higher for hyperplastic and dysplastic epithelia, and highest for squamous cell carcinoma. Cytoplasmic histone H3 mRNA and nuclear BrdU were localized in virtually identical areas of serial sections. The correlation coefficient for the relationship between these two LIs was 0.97 (P 0.001). These results suggest that the assessment of cell proliferation using H3 mRNA ISH will be a useful technique for investigating biological behavior during carcinogenesis.  相似文献   
56.
Malignant mesothelioma (MM) is caused by exposure to asbestos. Because MM has a latency period, short survival time, and has a poor response to current therapeutic regimes, long-term preventive strategies are required to suppress the advance of pathological states after asbestos exposure. Accumulating evidence suggests that adiponectin plays a crucial role in the regulation of energy metabolism by increasing AMP-activated protein kinase (AMPK) activation. Several studies have indicated that the activation of AMPK decreases cyclooxygenase (COX)-2 expression. Because high COX-2 levels correlated with a worse prognosis and survival rate in MM, we examined whether the adiponectin pathway suppresses MM cell growth through the AMPK/COX-2 pathway. In vivo, dietary fish oil (a potential promoter of adiponectin) decreased the growth rate of MM, which was accompanied by an increase in adiponectin and phospho-AMPK levels, and a decrease in COX-2 level. In vitro, adiponectin significantly impaired the cell proliferation rate of MM cell lines. These effects partly involved induction of growth arrest and apoptosis to MM cells. MM cells expressed both adiponectin receptors 1 and 2 (AdipoR1 and -R2) at mRNA and proteins levels. These receptors were functional, because adiponectin activated AMPK. Adiponectin treatment also significantly down-regulated protein levels of COX-2 and its downstream prostaglandin E(2). Finally, inhibitory analysis of AdipoR1/R2 by small interfering RNA knockdown suggests that adiponectin enhances AMPK activity and impairs the cell proliferation rate of MM cells, mainly via AdipoR1. These findings suggest that the induction or supplementation of adiponectin is an important tactic for developing therapeutic strategies against MM.  相似文献   
57.
58.
A new hydrocoating method (the thermal substrate method) has been proposed for coating calcium phosphates, such as hydroxyapatite, onto titanium substrates in an aqueous solution. The influences of several solution properties on the thermal substrate method were examined. The solutions used included 3 mmol dm(-3) Ca(H(2)PO(4))(2) and 7 mmol dm(-3) CaCl(2) as a reference concentration solution. The ion concentration was changed from 0.1 to 2 times with respect to the reference concentration. The experimental studies were conducted under the following conditions: temperature = 140 degrees C, heating time = 10-20 min., pH = 4-8 and Ca/P = 0.0167-16.7. The type of precipitate changed, depending on the pH and ion concentration. In the reference solution with pH > 6, predominantly hydroxyapatite was precipitated onto titanium. By contrast, only CaHPO(4) was formed in the solution of pH 4. In the solution with an ion concentration of one-tenth the reference solution, CaHPO(4) was also precipitated. The addition of H(3)PO(4) to the 0.1-times solution accelerated the precipitation rate of HA. It is suggested that the PO(4) (3-) concentration was insufficient to form HA in the Ca/P = 1.67 solution.  相似文献   
59.
Adult T-cell leukemia/lymphoma (ATLL) is a lymphoproliferative disease caused by human T-cell lymphotropic virus type 1 (HTLV-1) infection. HTLV-1 is spread by cell-to-cell transmission via the gp46-197 region, from Asp197 to Leu216, in the envelope protein gp46. A correlation exists between the prevalence and titer of the antibody recognizing the gp46-197 region (anti-gp46-197 antibody) and the severity of ATLL. In the present study, immunohistochemical staining was performed on samples of paraffin embedded lymph nodes of three different histological types of ATLL (anaplastic large cell type, n = 10; pleomorphic type, n = 10; and Hodgkin's-like type, n = 10) from 30 cases and 10 cases of HTLV-associated lymphadenitis. Of the three ATLL subtypes, gp46 expression was highest in the anaplastic large cell type, followed by the pleomorphic type and Hodgkin's-like type (mean: 53.4%, 34.9% and 16.0%, respectively; P= 0.0003). In HTLV-1 associated lymphadenitis cases, gp46 positive cells were rarely seen (4.0%). These results suggest that gp46-197 immunohistochemical staining can be a useful histological indicator for prediction of the aggressiveness of ATLL and prognosis for ATLL patients.  相似文献   
60.
We investigated the fine structure and mineral components of 29 stonelike masses obtained from the mesenteries of four adult cadavers, using optical microscopy, backscattered electron imaging, scanning electron microscopy, energy-dispersive X-ray microanalysis, and X-ray diffraction. Although the overall appearance of the stonelike masses measuring about 5–20mm in diameter and 0.06–3.1g in dry weight was roughly grouped into smooth bulb- and uneven bulk-shaped types, all the calcified masses basically consisted of core and mantle regions. The smooth bulb-shaped masses had a broad mantle with many concentric rings, whereas the uneven bulk-shaped masses contained a large core. In their core regions, spherulitic and short bundle-shaped deposits composed of needle-shaped apatite crystals were mainly found among loose collagen fibers. Their mantle regions, on the other hand, showed the concentric structures of dense collagen fibers in the intra- and/or extrafibrous calcification with fine sandy grain-shaped deposits. The mineral elements were mainly Ca and P, and the major crystals were hydroxyapatite. Hexahedral whitlockite containing Mg was a minor component. The fiber-rich mantle regions showed lower calcification and lesser crystallization than the fiber-poor core region. When necrotic or some tumor adipose tissues and necrotic lymphoid tissues that might have been caused by some digestive diseases are recognized as foreign matter, their tissues occasionally will be calcified and grow into stonelike masses. These stonelike masses tend to occur more often in women than in men.  相似文献   
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