Release of biological activities from quiescent fibronectin by a conformational change and limited proteolysis by matrix metalloproteinases

We reported that specific biological activities are confined to three domains of the fibronectin (Fn) molecule [Fukai et al. (1991) J. Biol. Chem. 266, 8807; Fukai et al. (1993) Biochemistry 32, 5746]: the potent ability to stimulate the adipocyte differentiation of ST-13 cells is in the amino-terminal fibrin-binding (Fib 1) domain (referred to as Fib 1 domain activity); the RGD-dependent activities that stimulate NIH-L13 cell migration and inhibit adipocyte differentiation are in the central cell-binding (Cell) domain (Cell domain activity); and the activity that stimulates cell migration in a RGD-independent manner is in the carboxyl-terminal fibrin-binding (Fib 2) domain (Fib 2 domain activity). Human plasma Fn which was purified without exposure to a denaturant, such as urea, exhibited no Fib 1, Fib 2, or Cell domain activity. By exposure to urea or surface adsorption, Fn showed Cell domain activity but not those of the Fib 1 and Fib 2 domains. Whether the cryptic domain activities are disclosed or not depended on whether or not the responsible domains were irreversibly exposed from confined environments of Fn structure as confirmed by light-scattering measurement and enzyme immunoassay using domain-specific monoclonal antibodies. We then investigated the action of matrix metalloproteinases (MMPs) in liberating the Fib 1, Cell, and Fib 2 domain activities. Matrilysin released only the Cell domain activity. In contrast, stromelysin, collagenase, and especially gelatinase A additionally liberated the Fib 1 and Fib 2 domain activities. The Fib 1, Fib 2, and Cell domains acquired much higher activities when they were freed from linkage with adjacent domains.(ABSTRACT TRUNCATED AT 250 WORDS)

Acinic cell tumour of the maxillary sinus: an unusual case initially diagnosed as parotid cancer

An unusual case of acinic cell tumour of the maxillary sinus is presented. The patient, a 41-year-old male who had undergone incomplete excision of the tumour in the left parotid region previously, was referred to our department for further treatment. The initial pathological diagnosis was adenocarcinoma of the parotid gland. CT-scan not only revealed tumours in the left pre-auricular and upper neck region, but also an enhanced mass in the left maxillary sinus. Although there were neither nasal symptoms nor destruction of the maxillary bone, aspiration biopsy of the maxillary sinus revealed class V. Total maxillectomy, radiotherapy and systemic chemotherapy were performed just after total parotidectomy and radical neck dissection at the left side. The clinical and histopathological findings are discussed.

Annual screening for oral cancer and precancer by invitation to 60-year-old residents of a city in Japan

Since 1986, annual screening for oral cancer and precancer by postal invitation has been undertaken among 60-year-old residents of Tokoname city, Japan. Clinical examination of the oral soft tissues is performed by groups of four different, specially trained general dental practitioners in the city health centre on one day each year. Following screening each subject receives an individual consultation with an oral medicine specialist. Individuals considered to need full diagnostic follow up or treatment are advised to attend a secondary care referral facility. Between 1986 and 1993, 802 out of 5187 eligible residents (15.5 per cent) were screened of whom 38 (4.7 per cent) were designated by the screeners as positive for oral cancer, erythroplakia, leukoplakia, lichen planus or chronic candidosis. Of these, 32 were referred and 25 attended for follow up examination in hospital departments by specialists with full diagnostic back up facilities. Twenty subjects were confirmed as having a potentially malignant lesion. For these referred patients only, the proportion of correct decisions by the screeners out of all oral cancer/precancer screening decisions was 81 per cent. Positive and negative predictive values for those attending for follow up were 0.80 and 0.82 respectively. Ways of improving the effectiveness and adequacy of the programme are considered.

Significance of urinary fibrin/fibrinogen degradation products (FDP) D-dimer measured by a highly sensitive ELISA method with a new monoclonal antibody (D-D E72) in various renal diseases

To diagnose the abnormalities of coagulation-fibrinolysis in various renal diseases, we developed a new monoclonal antibody (D-D E72) against fibrin/fibrinogen degradation products D-dimer (FDP D-dimer) and established a highly sensitive enzyme-linked immunosorbent assay (ELISA) for its measurement. FDP D-dimer was assessed in 102 patients with various renal diseases, and the following results were obtained: 1. The mean level of urinary FPD D-dimer in 32 normal controls was 0.69 +/- 0.60 ng/ml (mean +/- SD). 2. The level of urinary FDP D-dimer was significantly higher in primary nephrotic syndrome group (NS), chronic renal failure group (CRF) and in the group of diabetic nephropathy (DM) than in the control group. However, no difference was observed in the level of urinary FDP D-dimer between non-nephrotic chronic glomerulonephritis group (CGN) and control group. 3. No significant correlation was revealed between D-dimer and urinary protein in CGN and NS groups. These results suggest that in addition to plasma filtration the urinary FDP D-dimer in NS, CRF and DM may be also related to abnormalities of secondary fibrinolysis in intra-glomerular fibrin deposits.

Importance of hepatovenous back-perfusion for maintenance of liver viability during the Pringle manoeuvre

The role of hepatovenous back-perfusion in maintaining hepatic viability was investigated during inflow occlusion (Pringle manoeuvre) of the pig liver. The study compared two ischaemia procedures of 60 min duration: hepatic inflow occlusion and inflow plus outflow occlusion (vascular exclusion). Each procedure was carried out in six pigs and liver tissue perfusion, energy metabolism, lipid peroxidation and 7-day survival were assessed. Although all pigs survived after inflow occlusion, five of six died after vascular exclusion (P < 0.01). Exclusion induced a significant decrease in perfusion to 15.3 per cent of the value before ischaemia compared with 32.4 per cent after hepatic inflow occlusion alone (P < 0.01). Although cellular adenosine 5'-triphosphate levels were significantly decreased by ischaemia in both groups, the fall was less in pigs with inflow occlusion alone (to 55 per cent of the preclamp value) than in those with exclusion (to 24 per cent of the preclamp value) (P < 0.01). The plasma phosphatidylcholine hydroperoxide level rose immediately after reperfusion in pigs with exclusion, while the level remained constant after inflow occlusion alone. There is a fundamental difference between the two ischaemia procedures: back-perfusion from the vena cava contributes to the maintenance of liver function during inflow occlusion.

Microfilament Contraction Promotes Rounding of Tunic Slices: An Integumentary Defense System in the Colonial Ascidian Aplidium yamazii

In Aplidium yamazii, when a slice of a live colony (approximately 0.5 mm thick) was incubated in seawater for 12 h, the slice became a round tunic fragment. This tunic rounding was inhibited by freezing of the slices, incubation with Ca2+-Mg2+ -free seawater, or addition of cytochalasin B. Staining of microfilaments in the slices with phalloidin-FITC showed the existence of a cellular network in the tunic. Contraction of this cellular network probably promotes rounding of the tunic slice. In electron microscopic observations, a new tunic cuticle regenerated at the surface of the round tunic fragments; the tunic cuticle did not regenerate in newly sliced specimens nor in specimens in which rounding was experimentally inhibited. Based on these results, an integumentary defense system is proposed in this species as follows. (1) When the colony is wounded externally, contraction of the cellular network promotes tunic contraction around the wound. (2) The wound is almost closed by tunic contraction. (3) Tunic contraction increases the density of the filamentous components of the tunic at the wound, and it may accelerate the regeneration of tunic cuticle there.

[Clinical study on cerebrovascular diseases after renal transplantation]

Between October 1975 and December 1994, 131 renal transplants were performed on our hospital. Eight of these patients had 9 cerebrovascular diseases, which were 2 cerebral hemorrhages, 5 cerebral infarctions, 2 subarachnoid hemorrhages. Five of the 8 patients whose graft functions were bad died. We studied the relationship of the incidence of these complications to some factors as follows; 1) blood pressure, 2) hypercholestemia, 3) duration of hemodialysis, and 4) graft function. The cerebrovascular diseases after renal transplantation were related to the hypertension after renal transplantation and no correlation with the other factors could be found. Therefore, we think that the control of the hypertension after renal transplantation is the most important for the cerebrovascular diseases and the patient's prognosis.

Adult T cell leukemia clinically manifested with ascites and pleural effusion

A 62-year-old man with adult T cell leukemia (ATL) presented with complaints of anorexia and abdominal fullness. Evaluation revealed ascites and pleural effusion, but no lymph node swelling, hepatosplenomegaly, or skin involvement. The diagnosis of ATL was made by the detection of specific surface markers for T lymphocytes in pleural effusion and ascitic fluid, and by determination of human T cell leukemia virus type I (HTLV-I) proviral DNA integration in mononuclear cells of pleural effusion. This case was considered a rare type of ATL with infiltration of the pleura and peritoneum.

Induction of the antioxidant stress proteins heme oxygenase-1 and MSP23 by stress agents and oxidised LDL in cultured vascular smooth muscle cells

Enhanced expression of the antioxidant stress proteins heme oxygenase-1 (HO-1) and macrophage stress protein (MSP23) by oxidative stress agents and oxidatively modified low density lipoproteins (LDL) was investigated in cultured porcine aortic smooth muscle cells. Treatment of smooth muscle cells with glucose oxidase, CdCl2 or diethylmaleate resulted in a time-dependent (6-48 h) induction of HO-1 and MSP23 expression. Exposure of cells to 100 micrograms protein/ml highly oxidised LDL increased the expression of HO-1 and MSP23 within 24 h, and the induction was dependent on the degree of LDL oxidation. The induction of HO-1 and MSP23 may thus play an important cytoprotective role against oxidative stress in atherogenesis.

A novel ATP-dependent inward rectifier potassium channel expressed predominantly in glial cells

We have isolated a novel inward rectifier K+ channel predominantly expressed in glial cells of the central nervous system. Its amino acid sequence exhibited 53% identity with ROMK1 and approximately 40% identity with other inward rectifier K+ channels. Xenopus oocytes injected with cRNA derived from this clone expressed a K+ current, which showed classical inward rectifier K+ channel characteristics. Intracellular Mg.ATP was required to sustain channel activity in excised membrane patches, which is consistent with a Walker type-A ATP-binding domain on this clone. We designate this new clone as KAB-2 (the second type of inward rectifying K+ channel with an ATP-binding domain). In situ hybridization showed KAB-2 mRNA to be expressed predominantly in glial cells of the cerebellum and forebrain. This is the first description of the cloning of a glial cell inward rectifier potassium channel, which may be responsible for K+ buffering action of glial cells in the brain.

Reactivity of anti-erythrocyte antibody induced by Babesia gibsoni infection against aged erythrocytes

Effects of ageing treatment of erythrocytes to binding activity of the anti-erythrocyte antibody(s) in the serum of dogs infected artificially with Babesia gibsoni were examined by enzyme-linked immunosorbent assay (ELISA) using fixed cell antigen. When erythrocytes made senescent by two artificial ageing treatments, one of which was storing erythrocytes at 37 degrees C in medium for some days and the other was oxidation of erythrocytes with phenylhydrazine, reactivity of anti-erythrocyte antibody(s) in the infected serum to both types of treated erythrocytes was increased. These results suggest that such antibody(s) could play a role as one of the causes of anemia in canine babesiosis.

Effects of long-term cilazapril treatment on glucose and lipid metabolism in hypertensive patients with non-insulin-dependent diabetes mellitus

The effects of long-term cilazapril treatment on glucose and lipid metabolism were assessed in 25 hypertensive patients with non-insulin-dependent diabetes mellitus (NIDDM). Patients were treated with 0.5 to 1 mg of cilazapril once daily or a combination of cilazapril and other antihypertensive drugs once daily for 48 weeks. Both systolic and diastolic blood pressures were significantly reduced (P < 0.001) throughout the study with no significant changes in heart rate and no adverse effects such as cough. There were no significant changes in body mass index or serum levels of glycated hemoglobin A1c, fructosamine, total cholesterol, triglycerides, lipoproteins (high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and very-low-density lipoprotein cholesterol), or apolipoproteins (apo A-I, apo C-II, apo C-III, apo B, and apo E). Cilazapril caused a significant increase (P < 0.05) in levels of apo A-II and a significant decrease (P < 0.05) in the apo B:apo A-I ratio, an index of arteriosclerosis. These results suggest that cilazapril has favorable effects on glucose and lipid metabolism and that it may be useful as the first or second choice of antihypertensive drugs in hypertensive patients with NIDDM.

FT-IR and near-infrared FT-Raman study of aggregation of bacteriochlorophyll c in solutions: evidence for involvement of the ester group in the aggregation

Ultraviolet-visible (UV-Vis) absorption, Fourier-transform infrared (FT-IR), and near-infrared (NIR)-excited FT-Raman spectra have been measured for bacteriochlorophyll c (BChl-c) in acetone, tetrahydrofuran (THF), pyridine-d5, carbon disulfide (CS2), and water-saturated carbon tetrachloride (CCl4) to investigate its aggregation in vitro. The UV-Vis absorption spectra can be classified into two groups. Group I (acetone, THF, and pyridine-d5 solutions) gives a spectrum with a Qy band around 665 nm while group II (CS2 and water-saturated CCl4 solutions) shows a spectrum typical of BChl-c aggregates with a broader red-shifted Qy band. All the NIR-FT-Raman spectra, which are preresonant with the Qy band, are very close to those of chlorophyll a (Chl-a) measured in the corresponding solutions. Bands due to a C = O stretching mode of free and strongly hydrogen-bonded 13(1)-keto carbonyl groups appear near 1685 and 1645 cm-1, respectively. In contrast to the FT-Raman spectra, FT-IR spectra of the pyridine-d5 solution and group II are largely different from those of Chl-a in the corresponding solutions, suggesting that BChl-c forms quite different types of aggregates. It is clear from the IR spectra that the ester carbonyl group plays an important role in the aggregation for the pyridine-d5 and group II solutions. Of particular note is that bands due to C = O stretching modes of the ester group are observed at 1733, 1719, and 1705 cm-1 in the spectrum of BChl-c in water-saturated CCl4.(ABSTRACT TRUNCATED AT 250 WORDS)

Most thymocytes die in the absence of DNA fragmentation

Most thymocytes are known to be depleted from the thymus during T cell development, with the process of thymocyte death considered to be apoptosis. In this study we examined the mechanism of thymocyte death in the thymus of 6-week-old mice by using terminal deoxynucleotidyl transferase to detect DNA fragmentation or double strand breaks (TUNEL method). The TUNEL positive thymocytes were scattered throughout the cortex. Double staining of the section with the TUNEL method and acid phosphatase (ACP) activity showed that all the TUNEL positive cells were phagocytosed by ACP positive macrophages. An ultra-structural study revealed the presence of a substantial number of extremely small, unphagocytosed thymocytes throughout the cortex. These small unphagocytosed thymocytes were apparently dead cells, as based on several morphological features: 1) The majority were much smaller than red blood cells; 2) the nuclei were also considerably small; and 3) the extent of chromatin condensation was enormous. Importantly, these unphagocytosed dead thymocytes were TUNEL negative. These results indicate that: 1) DNA fragmentation, which is detected by the TUNEL method, is not involved in the cell death process of small unphagocytosed dead thymocytes shown in the present study; and that 2) typical apoptosis, which is characterized by DNA fragmentation, is not the dominant type of cell death in the normal murine thymus. Processes of cell death other than typical apoptosis taking place in most thymocytes require further investigation.

Induction of stress proteins in mouse peritoneal macrophages by the anti-rheumatic agents gold sodium thiomalate and auranofin

Gold sodium thiomalate and auranofin, anti-rheumatic gold-containing compounds, induced some stress proteins in cultured mouse peritoneal macrophages. The enhanced synthesis of two proteins, heme oxygenase (a 34-kDa protein) and a 23-kDa protein, was particularly prominent. The 23-kDa protein induced by the gold compounds was identical to that found in macrophages exposed to oxidative stress and was suggested to have antioxidant activity. Intraperitoneal injection of gold sodium thiomalate and oral administration of auranofin to mice induced enhanced synthesis of these proteins in peritoneal macrophages analyzed ex vivo. These data suggest that increased synthesis of these proteins may have a role in mediating the pharmacologic effect of these agents.

Changes in the molecular types of connectin and nebulin during development of chicken skeletal muscle

Changes in the molecular types of connectin and nebulin during development of chicken breast and leg muscles were determined by an improved SDS-polyacrylamide gel electrophoresis (PAGE) using 2% polyacrylamide slab gel. The adult leg-type alpha-connectin (alpha L-connectin) and nebulin (L-nebulin) appeared in embryonic breast muscle, and changed into the adult breast-type ones (alpha B-connectin, B-nebulin) specific for adult breast muscle after hatching. In leg muscle, alpha L-connectin and L-nebulin appeared in an embryonic stage, and remained unchanged in molecular types throughout the entire process of development. alpha-Connectin and nebulin seemed to be regulated by a similar mechanism during development. On the other hand, beta-connectin appeared in an earlier stage of development of the embryonic breast muscle, independently of alpha-connectin.

Subepithelial fiber components of the round window membrane of the guinea pig: an ultrastructural and immunohistochemical study

Subepithelial fiber components of the round window membrane (RWM) of the guinea pig were studied by the following methods: transmission electron microscopy (TEM), scanning electron microscopy (SEM) with NaOH treatment, high-voltage electron microscopy (HVEM) and immunohistochemical staining. SEM observation revealed intersecting collagen fibers and a vascular network in the middle layer. TEM observation showed that at the attachment region to the bone fibroblasts, collagen fibers and elastic fibers were intermingled with each other, and mesenchymal cells (bone-lining cells) were scattered on the surface of the bone. The cytoplasmic processes of fibroblasts and bone-lining cells were connected by interdigitations. HVEM demonstrated that collagen fibers of the RWM were directly linked to the fibers of the bone matrix. Immunohistochemically, the middle layer was positive for antibody to type I collagen. Immunoreaction for fibronectin was also positive at the middle layer and most intense in the region attached to the bone. Thus, the RWM is securely attached to the bone by type I collagen fibers together with the bone-lining cells and fibroblasts.

Primary malignant mesenchymoma of bone: case report, literature review, and distinction of this entity from mesenchymal and dedifferentiated chondrosarcoma

The seventh case of primary malignant mesenchymoma of bone is reported. It is compared to the other six cases in the literature and clinicopathologic pattern of this entity is developed. Primary malignant mesenchymoma of bone is compared to mesenchymal chondrosarcoma and dedifferentiated chondrosarcoma. Differences as well as similarities are discussed and a more current classification scheme for malignant mesenchymoma of bone is proposed.

[Tissue type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) in transplanted kidneys]

We have studied the involvement of fibrinolysis in acute rejection after kidney transplantation by analyzing changes in urinary levels of substances such as FDP, D-dimer, tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI). Fibrinolytic activity was found to be low (that is, PAI is dominant) during acute rejection, and it was elevated (that is, PA became dominant) as acute rejection subsided. It appears that the dominance of PA leads to an increase in the products of fibrinolysis and an elevation in the D-dimer/FDP ratio, resulting in disappearance of the acute rejection. Based on these findings, we thought it necessary to administer t-PA to kidney recipients so that PA becomes dominant earlier and the acute rejection can be reduced. It is necessary for us to directly study the phenomena within the kidneys. Therefore, we recently conducted a histochemical study of the distribution of t-PA, Urokinase type PA (u-PA) and PAI in transplanted kidneys. Transplanted kidney, which functioned well or showed signs of acute or chronic rejection, were biopsied. These renal samples as well as control samples (biopsied from normal nongrafted kidney) were examined as to distribution of t-PA, u-PA and PAI by the indirect enzyme complement method. In conclusion, t-PA, u-PA and PAI were detected in the glomeruli, arterioles, tubule and interstices of the control kidneys, well functioning grafts, acutely rejected grafts chronically rejected grafts. All samples showed intense chromatic responses in the arterioles and part of the tubules. On the whole, the chromatic response tended to be more intense in the acute rejection group than in the other group.

Effect of 24 weeks of treatment with epalrestat, an aldose reductase inhibitor, on peripheral neuropathy in patients with non-insulin-dependent diabetes mellitus

The effects of treatment with epalrestat, an aldose reductase inhibitor, on peripheral neuropathy were studied in 45 patients with non-insulin-dependent diabetes mellitus (NIDDM). Epalrestat 150 mg three times daily was given for 24 weeks. Subjective symptoms, such as spontaneous pain in the lower extremities and numbness and hypoesthesia of the extremities or trunk, were significantly (P < 0.001) relieved after 12 and 24 weeks of epalrestat treatment. Vibratory perception thresholds, as measured by using a tuning fork (C-128) and a vibrometer, were improved after 24 weeks of treatment. Furthermore, there were no adverse effects on glucose or lipid metabolism during treatment. These results suggest that long-term (24-week) epalrestat therapy can be used effectively to treat peripheral neuropathy in NIDDM patients without affecting glucose or lipid metabolism.

Hepatocyte growth factor stimulates liver regeneration and elevates blood protein level in normal and partially hepatectomized rats

The effects of recombinant human hepatocyte growth factor (HGF) on liver growth and function of normal and partially hepatectomized rats have been examined. HGF was continuously administered into the jugular vein because it was rapidly eliminated from the plasma (t1/2 alpha; approximately 4.5 min) and degraded. In normal rats, the labeling index of hepatocytes was increased about 6 times by the administration of HGF. HGF also decreased the prothrombin time and increased the hepaplastin and serum albumin content. In 70%-hepatectomized rats, HGF stimulated liver regeneration and increased the level of blood proteins such as hepaplastin in a dose-dependent manner. The stimulation of serum protein level seemed to result from not only the increase of hepatic cell number but also the direct effect of HGF on the protein production in hepatocytes, because HGF rapidly enhanced the protein synthesis prior to the increase of cell number and increased the mRNA content of albumin in the liver in vivo. In addition, a combination of heparin with HGF further accelerated the effects of HGF described above, possibly due to the decrease of HGF clearance. These findings suggest that HGF accelerates both the hepatic regeneration and function in vivo, and that rhHGF is clinically expected to be a potent therapeutic agent in hepatectomy and liver injury.