Tubulointerstitial injury induced in rats by a monoclonal antibody that inhibits function of a membrane inhibitor of complement

The kidney widely expresses membrane-associated complement regulatory proteins (membrane inhibitors of complement). The aim of this work was to evaluate the roles of these molecules in rat kidneys in vivo. To suppress functions of rat membrane inhibitors of complement, two mAbs, 512 and 6D1, were used. 5I2 and 6D1 inhibit functions of membrane inhibitors of complement at C3 level (rat Crry/p65) and C8/9 level (rat CD59), respectively. F(ab')2 fragment of 5I2 or 6D1 was perfused in the left kidneys, and perfusate was discarded from the renal vein. After perfusion, the left kidneys were connected to systemic circulation. In rats perfused with 5I2, mouse IgG was found in glomeruli, peritubular capillaries, vascular bundles, and tubules 15 min after recirculation. Binding of C3 and C5b-9 was evident in these areas. 1 d after perfusion with 5I2, cast formation, dilatation of tubular lumen, and tubular cell degeneration were observed. At day 4 through day 7, significant mononuclear cell infiltration and proximal tubule damage were observed. These changes were completely prevented by complement depletion. Rats perfused with 6D1 showed the binding of mouse IgG in the similar areas as 5I2, but C3 or C5b-9 deposition was not observed. Rats perfused with 6D1 or vehicle only did not show any pathology in the left kidneys. These results suggest that rat Crry/p65 plays protective roles against spontaneously occurring indiscriminate attack to tubulointerstitial tissues by autologous complement and that rat Crry/p65 is one of the important factors to maintain normal integrity of the kidney in rats.

[Ultrasonically guided needle biopsy of small mediastinal and peripheral pulmonary nodules]

From 1983 to 1993, we performed ultrasonically guided percutaneous needle biopsies on 320 thoracic tumors. Of these, 77 tumors were smaller than 3 cm in diameter and were peripherally located adjacent to the chest wall (n = 71) or in the posterior mediastinum (n = 6). We evaluated the efficacy and safety of UGNB for diagnosing these small lesions. The mean tumor size was 2.0 +/- 0.7 cm. Nine nodules were less than 1.0 cm in diameter, 38 were between 1.1 and 2.0 cm, and 30 were between 2.1 and 3.0 cm. Biopsies were done with a 17-gauge Trucut needle; a 21-gauge needle was used to aspirate specimens for cytological study. A definitive diagnosis was made in 31 (77%) of 40 malignant lesions and in 19 (51%) of 37 benign lesions. Complications included pneumothorax (n = 5) and hemoptysis (n = 3), but no special medications were needed. Thus, real-time sonographic guidance is a safe, easy, and reliable biopsy method for small pulmonary and mediastinal nodules adjacent to the chest wall.

Pulmonary blastoma: an ultrastructural and immunohistochemical study with special reference to nuclear filament aggregation

A case is presented of pulmonary blastoma occurring in the right upper lobe of a 25-year-old man without distinct clinical features and laboratory abnormality. Light microscopic analysis revealed that the tumor was composed of branching glands and morulae embedded in a primitive but bland mesenchyme. Immunohistochemically the epithelial cells were immunoreactive for cytokeratins, S-100 protein, protein gene product 9.5, chromogranin A, calcitonin, and Ki-67 (MIB-1); the mesenchymal cells were immunoreactive for vimentin, actin, cytokeratins, and Ki-67; and all the tumor cells were negative for p53, estrogen receptor protein, and human chorionic gonadotropin beta. Characteristically, many epithelial cells contained optically clear nuclei which were immunoreactive for biotin (M743). Electron microscopic analysis revealed that the optically clearing change was due to replacement of the central area of the nuclei by a mass of parallel-arranged 7- to 10-nm filaments, and biotin-immunoreactive products were mainly localized in the nuclear matrix. Additionally, spherical bodies were identified in the cytoplasm of the nuclear filament-aggregated cells, suggestive of an intimate pathogenetic association of the two morphological abnormalities. The similarity of the aggregated nuclear filaments to those observed in gestational endometrium and ovarian endometrioid carcinoma implies that a similar mechanism plays a role in the pathogenesis of these abnormalities.

Phasic motor activity reduction occurring with horizontal rapid eye movements during active sleep in human

We describe the phasic reduction of motor activity occurring with horizontal rapid eye movements (REMs) during active sleep in 15 children (12 healthy children and 3 patients with severe brain damage). A REM-related decrease in intercostal muscle activity was demonstrated by averaging integrated surface electromyograms. In the healthy subjects, this reduction had a mean latency from the REM onset of 37.1 ms and a duration of 225.9 ms. This phenomenon was also observed in the 3 patients who had lost cerebral function. We hypothesized a brainstem origin for the effect. A REM-related mentalis muscle activity loss, detected by averaging mentalis muscle twitches, was observed in 10 healthy children among the subjects. This loss began at 59.1 ms before the onset of REMs and lasted for 230.2 ms on average. In addition, a transient decrease in integrated REM activity surrounding mentalis muscle twitches (a twitch-related reduction of REMs) was observed. We discuss the similarity between REM-related phasic reduction of muscle activity obtained for intercostal and mentalis muscles and pontogeniculo-occipital (PGO) wave-related inhibitory postsynaptic potentials reported for feline lumbar and trigeminal motoneurons, respectively. We then assume the presence of a phasic event generator, functioning during active sleep in healthy humans, which triggers at least three generators; that is, the generator of PGO waves (or REMs), motor inhibition, and of motor excitation including muscle twitches.

Metanephric adenoma of the kidney: an electron microscopic and immunohistochemical study with quantitative DNA measurement by image analysis

Metanephric adenoma of the kidney is a newly recognized entity of renal adenoma, and the electron microscopic and immunohistochemical features of the tumor have not yet been well elucidated. The authors experienced a typical case of renal metanephric adenoma and studied the electron microscopic and immunohistochemical features of the tumor together with the DNA content of the tumor cells. Electron microscopically, the tumor was composed of immature epithelial cells with relatively uniform size, poor nuclear polarity, and scant cytoplasmic organelles arranged in small tubular or rosette pattern. Immunohistochemically, the cytoplasm of the majority of the tumor cells was positive for S-100, and occasionally for alpha-1-antitrypsin and vimentin. The tumor cells were also positive for cytokeratin, lysozyme, and Leu 7, with predominantly cell membrane staining. Only tumor cells arranged in papillary or large tubular pattern were positive for epithelial membrane antigen (EMA). Tumor cells were negative for Leu M1 and HMB-45. These immunohistochemical characteristics are quite similar to those of S-shaped body of the fetal kidney. An analysis of the nuclear DNA of the tumor cells by image cytometry revealed that the tumor entirely consisted of diploid cells' and lacked aneuploid cells. These results indicate that renal metanephric adenoma is composed of immature renal epithelial cells.

Expanded cavum septi pellucidi and cavum vergae associated with behavioral symptoms relieved by a stereotactic procedure: case report

CASE REPORT

A 6-year-old boy had symptoms such as unstable gait, behavioral symptoms, and irregular appetite, evacuation, and sleep. Giant cavum septi pellucidi and cavum vergae of 3 x 3 x 5 cm were revealed by computed tomography (CT) and magnetic resonance imaging (MRI). After stereotactic cyst-peritoneal shunting, regression of the cavities was revealed by CT and MRI, in association with marked improvement in the above-described symptoms. In the corpus callosum particularly, which had been preoperatively revealed on sagittal MRI sections to be extended circumferentially as a result of compression by a cyst; the compression was relieved postoperatively, and compression of the pericallosal brain tissue was also relieved.

CONCLUSIONS

Compression of the brain tissue around the cyst (limbic system, etc.) was considered the most important cause of the behavioral symptoms in this patient.

Molecular cloning of DNA for inhibin alpha-subunit from equine ovary

cDNA encoding equine inhibin alpha-subunit precursor protein was isolated from an equine ovarian cDNA library. For screening, the DNA probe was amplified by the RT-PCR using primers designed based on the rat inhibin alpha-subunit cDNA sequence. Out of 1.2 x 10(5) plaques screened, 19 positive clones were isolated, and one of these clones (Eq-alpha-11) contained a complete open reading frame encoding 367 amino acids. The similarity of the deduced amino acid sequences of both equine inhibin alpha-subunit precursor protein and the mature protein were greater than 80% to those of other six mammalian species, including bovine, porcine, ovine, human, rat and mouse. Northern blot analysis revealed that a single major band at 1.5 kb was present in the RNA samples both from equine follicles and testes.

Effect of a bacterial lipopolysaccharide on biliary excretion of a beta-lactam antibiotic, cefoperazone, in rats

Klebsiella pneumoniae O3 lipopolysaccharide (LPS) has been found to dramatically modify the pharmacokinetics of the beta-lactam antibiotic cefazolin in rats. This study investigated the effect of LPS on the biliary excretion of the beta-lactam antibiotic cefoperazone (CPZ) in rats. CPZ is known to be actively secreted into the bile by a carrier-mediated transport system. LPS (250 micrograms/kg of body weight) was infused for 20 to 30 min 2 h before an intravenous administration of CPZ (20 mg/kg). The pharmacokinetic parameters of CPZ were estimated by a noncompartment model. LPS induced a significant decrease in the systemic clearance (by approximately 50%) and an increase in the mean residence time of CPZ. Significant decreases were also seen in the bile flow rate and in the biliary recovery of unchanged CPZ in the LPS-treated rats. LPS tended to increase the proportion of urinary excretion of CPZ. LPS significantly decreased the biliary clearance (by approximately 55%) and renal clearance (by approximately 35%) of CPZ. However, no changes in the volume of distribution at steady state for CPZ were observed between the treatment groups. Our findings suggest that LPS induces changes in the pharmacokinetics of CPZ as a result of changes occurring in the biliary secretory system.

Detection of an increase in ascorbate radical in an irradiated experimental tumour system using ESR

We measured Asc.- (ascorbate radical) produced by the reaction of AscH- (ascorbic acid) with HO. or O2.- after irradiation in mouse. It is possible to measure Asc.- easily using ESR and a dialysis method in which Asc.- was collected at room temperature in the interstitial fluid through the dialysis membrane. After irradiation, Asc.- increased in both normal muscle and tumour tissues (SCC-VII) in proportion to the radiation dose. Asc.- increased after treatment with the agents H2O2 and FeCl2, while it decreased after treatment with SOD and catalase. These results suggest that the amount of HO. and O2.- produced is reflected in the Asc.- production. Also, the increase in Asc.- production when WR-2721 was administered prior to irradiation was less than for experiments in which irradiation only was performed. This method is useful for the following reasons. First, no special treatment, such as freezing of the sample, and no administration of noxious agents are necessary to measure Asc.-. Second, irradiation using a dose of only a few Gy shows an increase in production of Asc.-. Third, this method does not require removal of organs. Using this method, Asc.- can serve as an indicator of the amount of HO. and O2.- produced by irradiation in vivo.

Benefits of arterial reconstruction in claudication

We conducted a midterm follow-up of 150 claudicants who underwent surgical reconstruction by assessing cumulative patency, survival, and palliation (graft patency in live patients) rates. Eighty-nine claudicants (group I) underwent direct (in situ) proximal revascularization, 33 (group II) had indirect (ex situ) proximal revascularization, while 28 (group III) had distal revascularization. The secondary patency rates at 3 years were 97.5% in group I, 97.0% in group II, and 75.0% in group III, respectively. Only one patient with limb graft thrombosis required below-knee amputation. There were 3 perioperative deaths (2 in group I and 1 in group II). The survival rates at 3 years were 86.0% in group I, 69.5% in group II, and 95.8% in group III, respectively. The palliation rates at 3 years were 84.8% in group I, 70.0% in group II, and 77.9% in group III, respectively. These findings indicate the midterm benefits of supra- and infrainguinal arterial reconstructions, and also suggest that the preoperative assessment of risks in individual patients, the selection of the appropriate operative procedure and graft material, and intensive postoperative follow-up and management of any associated disease are all important aspects in the treatment of claudicants.

The first observation of O2- generation at real time in vivo from non-Kupffer sinusoidal cells in perfused rat liver during acute ethanol intoxication

Infusion of ethanol or phorbol myristate acetate (PMA) into the perfused rat liver immediately produces O2- which was detected directly by infusion of a Cypridina luciferin analogue, MCLA as a chemiluminescence reagent. The MCLA photon emission was inhibitable by SOD. Generation of O2- in the liver was further verified by nitroblue tetrazolium, formazan precipitate formation. Ethanol-induced O2- generation was unaffected by gadolinium chloride (GdCl3), an inhibitor of kupffer cells, while PMA induced O2- generation was completely abolished by GdCl3. Since PMA is a known stimulator of phagocytic cells including Kupffer cells, the results indicate, for the first time that ethanol stimulates a non-Kupffer cell population, probably liver sinusoid endothelial cell to produce O2-.

Nitric oxide-induced [3H] GABA release from cerebral cortical neurons is mediated by peroxynitrite

The functional significance of peroxynitrite in the release of [3H]GABA induced by nitric oxide (NO) liberated from NO generators was investigated using cerebral cortical neurons in primary culture. NO generators such as sodium nitroprusside (SNP) and S-nitroso-N-acetylpenicillamine (SNAP) increased [3H] GABA release in a dose-dependent manner. These increases in [3H]-GABA release were significantly inhibited by hemoglobin, indicating that those NO generators evoke the release of [3H] GABA by the formation of NO. Two types of superoxide scavengers, Cu2+/Zn2+ superoxide dismutase and ceruloplasmin, significantly reduced the increase in [3H]-GABA release induced by both SNP and SNAP, which assumes that NO requires superoxide to induce [3H]-GABA release from the neurons. In addition, synthesized peroxynitrite induced a dose-dependent increase in [3H]-GABA release from the neurons. These results indicate that NO-induced [3H] GABA release is mediated by peroxynitrite formed by the reaction of NO with superoxide.

[Measurement of radical in irradiated experimental tumor: direct detection of ascorbate radical in mice using ESR]

We measured ascorbate radical (AR) produced by the reaction of ascorbic acid (Asc) with hydroxyl radical (.OH) or superoxide (O2-) after irradiation in normal muscle and SCC-VII tumor of C3H/He mice. AR can be measured using electron spin resonance (ESR) equipment and the dialysis method. The tube for collecting AR was inserted such that the dialysis membrane was in contact with the normal thigh or the center of the tumor lesion. The AR in the interstitial fluid around the membrane was collected through the dialysis membrane. After irradiation with 10 Gy, AR increased in both the normal muscle and tumor tissue; the percent increase was 53.1% for normal muscle tissue and 33.8% for tumor tissue. The maximum percent increases in AR in the normal muscle and the tumor tissue were 11.7 and 9.5% for 2.5 Gy, 28.5 and 18.5% for 5 Gy, 53.1 and 33.8% for 10 Gy, and 88.5 and 44.8% for 15 Gy, respectively. The amount of AR increased to maximums of 144.3% and 160.1% after treatment with H2O2 and FeCl2, respectively, while it decreased to minimums of 65.3% and 81.3% after treatment with superoxide dismutase (SOD) and catalase, respectively. These results suggest that the amount of .OH and O2- is reflected in the amount of AR production. This method is useful for the following reasons. First, no special treatment, such as freezing of the samples, and no administration of noxious agents are necessary. Second, irradiation using a dose of only several Gy shows an increase in the production of AR. Third, this method is less invasive.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of the insulin-like growth factors (IGF) axis in a cultured mouse Leydig cell line (TM-3)

Characterization of the insulin-like growth factor (IGF) axis in a cultured mouse Leydig cell line (TM-3) was performed. Radioimmunoassayable IGF-I and IGF-II concentrations in TM-3 conditioned media (CM) were below the assay detection levels. Affinity cross-linking of IGF-I and IGF-II to crude membranes prepared from TM-3 cells revealed both type 1 and type 2 receptors and a 31 kDa IGF binding protein (IGFBP). Immunoprecipitation of solubilized crude membranes indicated that the 31 kDa protein was membrane associated IGFBP-4. Western ligand blots of CM from TM-3 cells demonstrated the presence of 24 and 28 kDa bands as major IGFBPs, and 25, 40, and 44 kDa as minor ones. The 28 kDa band could be invisible after Endoglycosidase-F treatment, suggesting that the 28 kDa IGFBP was a glycosylated form of IGFBP. The 24 kDa and 28 kDa bands were immunoprecipitated with an antibody to IGFBP-4. Treatment of TM-3 cells with IGF-I increased the levels of the 24 kDa IGFBP-4, as well as 25, 28, 40, and 44 kDa IGFBPs. IGF-I treatment also resulted in the appearance of a 29 kDa IGFBP. Neither the 25 nor 29 kDa bands were deglycosylated with Endoglycosidase-F nor immunoprecipitated by antibodies to rIGFBP-1 and -2. On the other hand, IGF-II treatment resulted in a significant decrease in the 24 kDa IGFBP-4.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmaceutical evaluation of carbamazepine suppositories in rats

The absorption of carbamazepine (CBZ) after rectal administration in the form of a suppository was studied in rats. CBZ suppositories were prepared with Witepsol H-15 (H-15), Witepsol S-55 (S-55) or polyethylene glycol 6000 (PEG) bases by moulding procedure. An in vitro investigation was undertaken using a dissolution apparatus. The in vitro dissolution rate of CBZ showed marked differences among the bases in the order PEG > H-15 > S-55. An in vivo study demonstrated marked differences in the time required to reach peak plasma concentration (Tmax) of CBZ after rectal and oral administration: the absorption of CBZ from PEG base was the most prolonged among these bases (in the order PEG > H-15 > S-55 > ORAL). Comparison of the area under the plasma concentration-time curve (AUC) of CBZ after rectal administration of the three different suppositories with those after intravenous and oral administration showed no significant differences in the AUC among the five preparations. These results suggest the possibility that CBZ suppositories can replace oral treatment for epilepsy.

Influence of a newly developed quinolone, T-3761, on pharmacokinetics of theophylline in rats

The effect of a new quinolone, T-3761, on the pharmacokinetics and metabolism of theophylline was investigated with rats. T-3761 at a high dose (20 mg/kg of body weight) was injected intravenously 10 min before an intravenous administration of theophylline (10 mg/kg). The presence of T-3761 slightly delayed the disappearance of theophylline from plasma. Parameters related to the pharmacokinetic interaction between theophylline and T-3761 were estimated by noncompartmental methods. A significant decrease (approximately 25%) in the systemic clearance of theophylline was observed in the presence of T-3761. However, no significant changes between the control group and the T-3761-treated groups in the volume of distribution at a steady state were observed. Pretreatment with T-3761 increased the urinary excretion of unchanged theophylline (by approximately 25%) and decreased the nonrenal clearances (by approximately 30%), indicating that T-3761 inhibits the metabolism of theophylline. These findings suggest that T-3761 at the dose used in this study affects the pharmacokinetics and metabolism of theophylline.

Donor card registration system in Japan: an obstacle to procuring kidneys for transplantation

Donor cards are a simple and effective way to give a consent to organ donation in cases of unexpected death. In Japan the prevalence of donor cards is low (0.4%) compared to the United States (24.6%), although about 50% of Japanese people are reported to be willing to donate their organs after death, a figure equivalent to the United States. We hypothesized that the donor card registration system can explain the low prevalence, and an introduction of a free delivery system will increase the prevalence. From April 1992 to April 1993, 402 high school students and 3391 workers in the Tokyo metropolitan area were requested to answer questionnaires; all the questionnaires were returned. Few respondents (15.5%) knew the way in which to be registered as a donor card holder. If donor cards were delivered freely and registration to carry a donor card was not required, 48.8% replied that they would be willing to carry donor cards. The most commonly cited reason for not carrying a donor card was 'I had no opportunity to get a donor card'. This study indicates that the introduction of free delivery of donor cards will increase the prevalence dramatically if a sufficient number of opportunities are offered. We recommend that a free delivery system should be introduced in order to increase the prevalence and secure the will of the deceased rather than the will of the family.

Effects of traditional Chinese medicines on pharmacokinetics of levofloxacin

The effects of single coadministrations of one of three traditional Chinese medicines, Hotyu-ekki-to, Rikkunshi-to, and Juzen-taiho-to, on the pharmacokinetics of levofloxacin (LVFX) were investigated with eight healthy volunteers in an open, random crossover fashion. Subjects each received a single oral dose of LVFX (200 mg) alone and then with a single coadministration of each Chinese medicine. There were no significant differences in any pharmacokinetic parameters of LVFX between the groups. Also, no significant changes in the urinary recovery (> 80%) and renal clearance of LVFX were observed. These results indicate that the Chinese medicines tested have no significant effect on the rate and extent of bioavailability or renal excretion of LVFX.

Quantitative analysis of molecular orientation in chlorophyll a Langmuir monolayer: a polarized visible reflection spectroscopic study

Polarized visible reflection spectra of a chlorophyll a (Chl.a) Langmuir monolayer have been measured in situ at various surface pressures. By applying Hansen's optics to the three-phase plane-bounded system (air/Chl.a monolayer/water), the negative reflection absorbances observed were reproduced satisfactorily by the theoretical calculation. Molecular orientation of Chl.a in the monolayer was evaluated quantitatively as a function of surface pressure, from the reflection absorbance of p- and s-polarized spectra of the red (Qy) band. It has been proven that Chl.a molecules in the monolayer form aggregates (islands) even in the low surface pressure region and that during the monolayer compression the molecules are gradually reorganized from inhomogeneous islands to ordered structures, with the chromophores oriented on the average vertically to the water surface.

Prognostic implication of the p53 protein and Ki-67 antigen immunohistochemistry in malignant fibrous histiocytoma

BACKGROUND

Mounting evidence indicates that p53 regulates cell growth and abnormal p53 immunophenotypic expression is associated with an unfavorable prognosis for patients with some types of carcinoma. The prognostic significance of p53 overexpression in malignant fibrous histiocytomas (MFHs) of soft tissue has not yet been elucidated.

METHODS

Expressions of p53 protein and Ki-67 antigen in 54 primary MFHs of soft tissue were investigated immunohistochemically and indexed quantitatively by counting the number of immunoreactive nuclei versus the total neoplastic nuclei in the representative fields of each tumor to evaluate their prognostic implications and interrelations with other clinicopathologic parameters.

RESULTS

The percentages (labeling indices [LIs]) of p53 and Ki-67-immunoreactive nuclei versus the total neoplastic nuclei were 0.1-93.2% (mean +/- standard deviation [SD], 40.6% +/- 21.8%) and 5.3-90.8% (mean +/- SD, 42.7% +/- 29.4%), respectively. The Ki-67 LI correlated with histologic grade (P = 0.01498), primary tumor size (P = 0.04985), disease free interval (reverse correlation, P = 0.00776), and recurrence and metastasis (P = 0.00360). The p53 LI correlated with primary tumor size (P = 0.00431) but did not show any significant correlation with histologic grade, Ki-67 LI, primary tumor size, disease free interval, or recurrence and metastasis. Other significant correlations included histologic grade and disease free interval (P = 0.00010), primary tumor size and disease free interval (reverse correlation, P = 0.00869), histologic grade and recurrence (P = 0.02714), and primary tumor size and primary tumor location (P = 0.00028). In the grouped survival analysis, patients with recurrence or metastasis or with tumors of larger size (> or = 7 cm), high histologic grade, or higher Ki-67 LI (> or = 25%) had a significantly reduced survival (P < 0.05). The different p53 immunohistochemical expression and the different histologic types did not reflect different cumulative survival (P > 0.05). Regression analysis revealed that the primary tumor size and histologic grade, but not Ki-67 or p53 LIs, were independent statistical variables for prognostication.

CONCLUSIONS

These results indicate that (1) primary tumor size and histologic grade are two important prognostic factors, (2) Ki-67 LI should be used in adjunct with other main prognostic factors for patients with MFHs, and (3) nuclear p53 overexpression in MFHs of soft tissue is a comparatively common event that has no prognostic implication.

Differentiation and proliferative activity in benign and malignant cartilage tumors of bone

To assess the histological grade in benign and malignant cartilage tumors of bone by more objective methods, we examined the differentiation and proliferative activity of tumor cells in six enchondromas, five chondroblastomas, and 13 chondrosarcomas immunohistochemically. A variable number of cells in all tumors showed S-100 protein and vimentin immunoreactivity. In fully differentiated cartilage of enchondromas and low grade chondrosarcomas, tenascin, which is an extracellular matrix glycoprotein, was present in small amounts or absent but was increased at the periphery of tumor lobules and even in the matrix throughout the high grade chondrosarcomas. Higher rate and intensity of proliferating cell nuclear antigen (PCNA) reactivity were found in chondrosarcomas, especially in spindle-shaped cells of high grade tumors, than in enchondromas. The distribution of PCNA-positive cells almost corresponded to the regions with tenascin reactivity. One tumor of high grade chondrosarcoma showed p53 protein immunoreactivity. Aberrant expression of cytokeratin was observed in four chondroblastomas. The expression of desmin was identified in relatively large proportions of enchondromas and chondrosarcomas, regardless of their benign or malignant nature and histological grade. Smooth muscle or muscle-specific actins also were present in a smaller number of tumors. Based on these findings, it is concluded that unusual staining characteristics were present, in addition to those of a chondroblastic nature, in the cartilage tumors of bone. Tenascin and PCNA positivity of various degrees in all chondroblastomas may suggest that they are chondrogenic tumors having a relatively high proliferative activity, albeit their benign clinical course. Proliferative activity of tumor cells in enchondromas and chondrosarcomas correlated well with their histological grade. Tenascin may play a role in promoting tumor cell proliferation of cartilagenous neoplasms and, on the other hand, the alterations of extracellular matrix involving tenascin synthesis seem to be a result of tumor development.

Proteolytic activity of IGFBP-3 in various clinical conditions during childhood studied by means of western immunoblotting

Insulin-like growth factors (IGFs) have 6 types of binding proteins (IGFBPs), and IGFBP-3 is the major IGFBP in human sera. A proteolytic enzyme for IGFBP-3 has recently been reported to be present in human and animal pregnant sera. Although the physiological significance of a pregnancy-associated IGFBP-3 protease remains to be established, the proteolysis could result in lowering the affinity for IGFs, thereby enhancing their delivery to target tissues by increasing free IGFs in the circulation. The methods for detection of IGFBP-3 protease which have been widely used so far are a method reported by Lamson et al. which used affinity crosslinking or western ligand blotting. These methods need radioactive materials (iodinated IGFs and IGFBP-3) and it takes at least a few days to get the results. We have now developed a simple assay for the proteolysis of IGFBP-3. The method is western immunoblotting without radioactive materials. The results can be obtained in a day. With this method, we proved the absence of significant proteolytic activity in sera from rapidly growing children (early stage of puberty or precocious puberty), and sera from a severe type of growth hormone deficiency. Significant proteolytic activity, as in pregnant women, was detected in 6 out of 11 patients with acute disorders such as measles, Kawasaki disease, bacterial meningitis and mycoplasma pneumonia, some of whom were probably in a catabolic condition. These data suggests that the proteolysis of IGFBP-3 might also be important in modulating IGF action in some acute diseases during childhood. The increased bioavailability of IGFs by IGFBP-3 proteolysis may play a role in overcoming catabolic conditions.