Biomedical subjects
Publications and source records attributed to S Kanda.
Inflammatory pseudotumor of the urinary bladder is a benign proliferative lesion of the submucosa and its treatment has not yet been established. Here we present a case of spontaneously regressed inflammatory pseudotumor of the urinary bladder.
In infant mice (2 weeks old) fed a diet with excess iron for one week, numerous huge iron particles around micro blood vessels under the basement membrane of intestinal epithelial cells were observed by electron microscopy. The frequency of occurrence of these particles (0.24 +/- 0.04 micron diameter) was markedly higher in mice fed a casein-based diet than in mice fed an amino acid-based diet. The quantity of these particles in both groups decreased in proportion to the term of 2 or 3 weeks. Changes in morphological features, such as opening of the intercellular junctions between intestinal epithelial cells, were also observed in these experimental groups. On the other hand, in mice fed the casein-based diet with excess iron, fat globules appeared in the intestinal epithelial tissue (intestinal epithelial cells, interstitial tissue, lympha) and the occurrence of these increased gradually in proportion to the term of feeding. These fat globules were not observed in mice fed the amino acid-based diet with excess iron. These phenomena might be elicited temporally in infant mice fed excess iron together with protein. The mechanisms of fat globule formation remain unclear.
A case of pyonephrosis with high levels of serum CA19-9 antigen is reported. A 71-year-old woman was admitted with right flank pain. Computed tomography and ultrasonography showed severe hydronephrosis and hydroureter due to a right ureter stone. Laboratory data revealed a high level of serum CA19-9. However, no tumor was found in the pancreas, gallbladder, liver, gastrointenstinal tract or genitourinary tract. Drip infusion pyelography showed a non-functioning pattern of right kidney. Therefore, right nephroureterectomy was performed for right pyonephrosis. Histological examination revealed chronic inflammation. Malignant cells were not seen in the resected specimen. The serum CA19-9 levels before and after operation were 102.9 U/ml and 24 U/ml, respectively, being normal after the operation. Immunohistochemical examination revealed the presence of CA19-9 antigen in the urethelium, indicating its expression in the specimen. To our knowledge this might be the first case of pyonephrosis associated with high levels of serum CA19-9 antigen.
We have previously shown, in a radioligand binding study with single ventricular myocytes, that benzothiazepine and dihydropyridine binding sites interact with each other. To further examine whether this interaction between the two binding sites is reflected in the function of L-type Ca2+ channels, the blocking action of diltiazem, nitrendipine, and the combination of these two drugs on L-type Ca2+ channel currents was investigated using baby hamster kidney cells expressing the alpha 1C, alpha 2/delta, beta and gamma subunits of the Ca2+ channel. The effects of diltiazem and nitrendipine were additive at room temperature but synergistic at 33 degrees C. The use-dependent block by 3 microM of diltiazem was significantly enhanced from 28% to 68% by addition of 30 nM of nitrendipine, which by itself did not have a blocking effect. Thus, we conclude that benzothiazepine- and dihydropyridine binding sites interact and potentiate their blocking action on L-type Ca2+ channels in a temperature-dependent manner.
Cultured vascular endothelial cells derived from bovine aorta (BAECs) can survive and proliferate in the condition of two-dimensional monolayer culture in the presence of serum without any specific growth factors. When BAECs were embedded in collagen lattice, they underwent apoptotic death within 2 days unless the cultures were repeatedly supplied with angiogenic growth factor such as fibroblast growth factor-2 (FGF-2). Supplementation with FGF-2 induced endothelial cell differentiation, resulting in capillary-like tube formation inside collagen lattice. Following tube formation, withdrawal of FGF-2 induced disruption of the tube structures associated with the characteristic apoptotic cell death. These effects of FGF-2 were regulated by tyrosine phosphorylation, but not mediated through protein kinase C pathway. This model of endothelial cell apoptosis inside collagen lattice may represent in vivo endothelial cell-matrix interaction during angiogenesis process, indicating that apoptotic death of endothelial cells may regulate angiogenesis and the regression of vessels.
Programmed cell death (PCD) is an essential event for development. The purpose of this work was to ascertain how PCD, in vivo designated apoptosis, is involved in the development of the external auditory canal. We performed a time sequence study of the distribution of apoptosis during the development of external auditory canal (EAC) of the mouse. ICR mice ranging in age from embryonic day 11.5 (E11.5) to 12 days after birth (DAB) were used in the present study. A part of each head including both ears was removed and was processed according to its purpose. Light and electron microscopy for morphological studies and TUNEL method (Gavrieli et al. [1992] J Cell Biol., 119:493-501) for histochemical studies were used. On E11.5, distinct TUNEL-positive staining occurred in the branchial arch. Between E15.5 and 1DAB, TUNEL-positive cells were observed throughout the EAC and the number of these cells decreased with age. On E15.5 and E16.5, numerous TUNEL-positive cells were observed in a cavity remained in the epithelial plate. Transmission electron microscopy revealed that these cells had the features of apoptosis. From 3-12 DAB, no apoptosis was observed in the EAC except for the terminal differentiation of the skin of the EAC. Apoptosis was not observed during recanalization of the EAC, but occurred during the formation of the epithelial plate. The investigation established that PCD is involved in the formation of the epithelial plate, whereas only cornification of the epithelium of the EAC is associated with recanalization.
Advanced glycation endproduct (AGE) accumulation in extracellular matrix proteins has been demonstrated in diabetic patients with a significant correlation with the severity of diabetic complications. AGE accumulation induces matrix protein cross-link formation, resulting in an increased stiffness of matrix fibres and the reduction of the susceptibility of matrix proteins to proteolytic degradation. We examined whether glycation-induced collagen cross-linking may affect vascular endothelial cell behaviours such as invasion, proliferation and differentiation, using the in vitro angiogenesis model of capillary-like structure formation in three-dimensional matrices of collagen type I. Endothelial cells cultured on collagen gel with angiogenic factors (the combination of fibroblast growth factor-2 and vascular endothelial growth factor) invaded the underlying collagen matrix, and organized capillary-like cord structures in the gel. We found that endothelial cell invasion into glycated collagen gel was significantly attenuated without any effect on proteinase activity including cell-associated plasminogen activator and matrix metalloproteinase in the conditioned medium. In addition, subsequent capillary-like cord formation was also inhibited in glycated collagen gel. In contrast, endothelial cell proliferation was enhanced on glycated collagen gel with or without angiogenic factors compared with control collagen gel. These results suggest that the structural alterations of extracellular matrix proteins through the glycation-induced cross-link formation affect the interaction between endothelial cell and extracellular matrix, resulting in the impairment of an adequate neovascularization in diabetic patients.
The regulatory effects of fosfomycin (FOM) were correlated closely with the multifunction of TGF-beta in the modulation of immune responses in vivo and in vitro. LPS-induced polyclonal IgM and IgG antibody responses were depressed at 3 days after the initial culture and subsequently enhanced at day 10 by FOM or TGF-beta. Neither FOM nor TGF-beta inhibited LPS-induced IgA antibody responses, whereas dexamethasone (DX) reduced polyclonal IgM, IgG and IgA antibody responses wholly. The suppression of antibody responses and Mv1Lu cell proliferation induced by FOM or TGF-beta was partly overcome with soluble TFG-beta receptors (sRIII). Oral, i.v. and i.p. administration of FOM exhibited similar enhanced SRBC-specific antibody responses to that seen after oral administration of TGF-beta. The addition of FOM and latent TGF-beta inhibited the proliferation of Mv1Lu cells, but FOM did not lead to an increase in plasmin activities, which convert latent to active TGF-beta, and further the expression of TGF-beta receptors on the cell surface. In addition, FOM failed to enhance TGF-beta secretion. These findings suggest that immunomodulation of FOM results in increased sensitivity of cells to TGF-beta.
OBJECTIVE: The purpose of this study was to review and illustrate the appearances on diagnostic images of pathologic conditions of the buccomasseteric region. STUDY DESIGN: Computed tomographic, sonographic, and magnetic resonance images of the buccomasseteric masses were reviewed retrospectively. RESULTS: In our series of 66 cases, there were 60 benign lesions; of these, 21 were benign masses, 11 were inflammations, and 28 were myopathies. The most common pathologic condition of the buccomasseteric region was masseteric hypertrophy (n = 22). The most common lesion manifesting as a benign mass in this series was hemangioma (n = 10), which was followed by lipoma (n = 6). Six of the 66 patients had malignant tumors. CONCLUSIONS: Computed tomography and magnetic resonance imaging were useful in demonstrating the location and extent of the buccomasseteric masses. Sonography provided clear images of internal architectures of the mass in this region.
Six patients with mucoepidermoid carcinoma in the mandible were studied with both panoramic radiography and computed tomography. Lesion shape and margin were evaluated on panoramic radiography, and bony expansion and cortical plate destruction were evaluated on computed tomography. In addition, a possible correlation among radiographic findings, histologic findings, and prognosis was investigated. Lesions found on panoramic radiography were classified into three types; each type pertained to two of the six patients. The lesion types were as follows: cystic, characterized by a large, cystic radiolucent area; rarefying, characterized by rarefying changes of the trabeculae; and infiltrative, characterized by a central ill-defined area of bony destruction. The results show that computed tomography is useful in the identification of tumor extent, bony expansion, and cortical plate destruction resulting from tumors. None of the patients whose lesions were of the cystic or rarefying type showed evidence of disease after surgery. In contrast, both of the patients whose lesions were of the infiltrative type died of their tumors. Histologic findings of the cystic and rarefying types showed tumors that were well-differentiated or moderately well-differentiated, whereas findings of the infiltrative type showed poorly differentiated tumors. Radiographic findings correlated with histologic findings and prognosis of mucoepidermoid carcinoma in the mandible in this limited series.
OBJECTIVE: The sonographic features of recurrent parotitis in children were studied to clarify a relationship between sonographic and sialographic findings in this disease. STUDY DESIGN: Twenty-one glands (7 on follow-up) were examined by 7.5 MHz ultrasonography and sialography. Echo intensity level, distribution of the internal echoes, and size of hypoechoic areas were compared with the size of punctate shadows on the sialograms. Twenty other histopathologic specimens were analyzed to investigate the entity of hypoechoic areas. RESULTS: Sonography showed hypoechoic, heterogeneous internal echoes, the level of which increased as the punctate shadows enlarged. Hypoechoic areas, all of which were larger than the sialographic punctate shadows, were observed in 62% of the glands. Histopathologic analysis suggests that these hypoechoic areas represent dilated peripheral ducts with lymphocytic infiltration. Sonography was likely to detect changes over time more sensitively than sialography. CONCLUSIONS: Sonography should be performed as the test of first choice, both in the primary and follow-up stages, in cases of recurrent parotitis in children.
Two adult patients with rhabdomyosarcoma of the infratemporal fossa region were evaluated by computed tomography and magnetic resonance imaging both before and after treatment. Successful treatment accompanied by reduction of the tumor mass as a result of chemotherapy was demonstrated in one patient. In the other patient a subsequent increase in the tumor mass was documented. Information on not only the size but also the internal architecture of the tumor may be useful when tumor response to therapy is being investigated. Magnetic resonance imaging is recommended as a method for outcomes evaluation in adult rhabdomyosarcoma cases.
OBJECTIVES: To describe the CT appearances of 4 cases of the calcifying odontogenic cyst (COC) with particular reference to the effect of varying the window settings. METHODS: Conventional radiographs and CT scans of 4 calcifying odontogenic cysts were analyzed with respect to the presence of an impacted tooth, root resorption and calcification. In addition, increased attenuation by desquamated keratin was examined by varying the window settings on CT. RESULTS: All lesions were located in the maxilla and on conventional radiographs, had unilocular radiolucency with a well-defined margin. Calcifications and inclusion of an impacted tooth were seen in all cases. Root resorption was observed in two cases, but was not prominent. On CT, calcification was detected at the periphery of the lesion and/or around the impacted tooth in all cases. Varying the window setting revealed an increased attenuation area due to desquamated keratin. CONCLUSIONS: Varying the window setting on CT is useful as a means of identifying both desquamated keratin and peripheral calcification in COC.
The latent form of transforming growth factor-beta (TGF-beta) in human milk and platelets was converted to the active form when conscious, pylorus-ligated mice were given human milk and platelets by intragastric intubation. Oral administration of TGF-beta exerted enhancing effects on the natural killer (NK)-cell activities in spleen and liver. Augmentation of NK-cell activities in spleen was observed for 7 days after oral administration of TGF-beta. TGF-beta at concentrations of 5 and 20 ng produced the greatest augmentation of NK-cell activities in spleen. However, NK-cell activities in spleen were unaffected when TGF-beta was given intravenously. Interleukin (IL)-12 production in spleen was enhanced by oral administration of TGF-beta, but not by intravenous administration of TGF-beta. These findings suggest that large amounts of TGF-beta in human milk are involved in early antiviral protection through the augmentation of NK-cell activities.
The interaction between macrophages and oxidatively modified low density lipoprotein (Ox-LDL) appears to play a central role in the development of atherosclerosis, not only through foam cell formation but also via the induction of numerous cytokines and growth factors. The current study demonstrated that Ox-LDL upregulated vascular endothelial growth factor (VEGF) mRNA expression in RAW 264 cells, a monocytic cell line, in a time- and concentration-dependent manner and that Ox-LDL stimulated VEGF protein secretion from the cells. Lysophosphatidylcholine, a component of Ox-LDL, also enhanced VEGF mRNA expression in RAW 264 cells and VEGF secretion from RAW 264 cells, with a maximal effect at a concentration of 10 micromol/L lysophosphatidylcholine. Immunohistochemical studies showed that human early atherosclerotic lesions exhibited intense VEGF immunoreactivity in subendothelial macrophage-rich regions of the thickened intima. In atherosclerotic plaques, VEGF staining was also observed in foam cell-rich regions adjacent to the lipid core or the neovascularized basal regions of plaque consisting predominantly of smooth muscle cells. High-power-field observation revealed that VEGF was localized in the extracellular space as well as at the macrophage cell surface. These observations suggest the possible involvement of Ox-LDL in the development of human atherosclerosis through VEGF induction in macrophages.
A seven-hour-old female neonate visited our hospital because of the anormaly of external urethral meatus. An interlabial cystic mass, the diameter of which was about 1 cm, was observed and an external urethral meatus could not be found. Direct needle aspiration of the cystic mass showed a small quantity of milky fluid and an urethral meatus was then identified.
The changes in fine structure of the intestinal tract in young adult (4 week-old) and infant (2 week-old) mice fed a diet containing different amounts of iron salt (Fe-0, Fe-2.5, Fe-25: 0, 2.5 and 25 mg Fe/100 g diet, respectively) for a long-term (1 or 2 weeks) were investigated. The hepatic iron levels in infant mice fed Fe-25 for 2 weeks were significantly higher than those observed after 1 week of feeding, but there was no such increase in young adult mice during the feeding period. Observations of fine structure indicated typical signs of impairment of enterocytes due to excess iron such as the opening of intercellular junctions between adjacent epithelial cells and the marked appearance of eosinophilic leukocytes outside the basement membrane in young adult and infant mice fed Fe-25. The frequency of the opening in intercellular junctions increased in young adult mice fed Fe-25 for 2 weeks, but decreased in infant mice. On the contrary, under iron-deficient conditions, the frequency in infant mice was higher than that in young adult mice. The appearance of eosinophilic leukocytes indicated that some immunological reaction was elicited in both groups of mice fed Fe-25 for 2 weeks.
In remodeling tissues the formation of new blood vessels is an essential process which is regulated by different factors. During such processes an increase in hyaluronan synthesis and turnover is often seen and recent observations have suggested that hyaluronan can both promote and inhibit neovascularization depending on its molecular mass. In this work we show that a brain capillary endothelial cell line forms tubes in a collagen gel after stimulation by hyaluronan oligosaccharides. Ultrastructural examination of the tubes by transmission electron microscopy revealed that the cord-like outgrowths consisted of 2-10 tightly packed cells containing a continuous lumen. The tube formation in response to hyaluronan oligosaccharide was not mediated by activation of receptors for fibroblast growth factor. The endothelial cell line, which does not synthesize hyaluronan, exhibited specific hyaluronan-binding sites, with about 3000 hyaluronan molecules (M(r) 3.85 x 10(6)) bound per cell at saturation and Kd was 0.05 x 10(-9) M. Furthermore, the cell line was stained with mAb IVd4 that recognizes a novel class of hyaluronan-binding proteins and mAb IM7 which recognizes CD44 molecules.