Effect of iohexol on pulmonary arterial pressure at pulmonary angiography in patients with pulmonary hypertension

The effects of 300 mgI/ml of iohexol on pulmonary arterial pressure at selective pulmonary angiography were evaluated in seven patients with pulmonary hypertension due to pulmonary thromboembolism. The total number of contrast injections was 26. Pulmonary arterial pressure was recorded before and after each injection. The effect of iohexol on pulmonary arterial pressure in the pulmonary hypertensive circulation was slight. The results suggest that iohexol at 300 mgI/ml may be safe as a contrast medium for selective pulmonary angiography in patients with pulmonary hypertension.

[Changes in renal function immediately after the angiography]

The effect of radiographic contrast media upon renal function was investigated in 30 patients with normal renal function using Ioxaglate 320 mgI/ml (0.58 Osm/KgH2O), Iohexol 350 mgI/ml (0.88 Osm/kgH2O) and Iomeprol 400 mgI/ml (0.75 Osm/kgH2O). Before and immediately after conventional abdominal angiography, serum and urinary BUN, creatinine, sodium, osmolality and urinary volume were examined. Urinary minute volume increased remarkably immediately after angiography in all the contrast media groups. In Iohexol 350 and Iomeprol 400, creatinine clearance (Ccr) increased immediately after angiography, while no Ccr increase was observed in Ioxaglate 320. FENa increased immediately after angiography in all the contrast media groups. There were no statistical differences in the changes of FENa among Ioxaglate 320, Iohexol 350 and Iomeprol 400. There was no significant change in CH2O. It becomes evident that the osmotic diuresis and its effect on the proximal tubular function are induced by administrated low osmolar contrast media and that these changes are reversible.

Presence of pancreatic alpha-amylase, trypsinogen, and lipase immunoreactivity in normal human pancreatic ducts

Presence of pancreatic alpha-amylase, trypsinogen, and lipase in normal pancreatic ducts was evaluated immunohistochemically in 10 surgically resected normal pancreatic specimens, using monoclonal antibodies against human pancreatic alpha-amylase, trypsinogen, and lipase. Immunoreactivity to all enzymes occurred patchily in some epithelial cells not only of the common bile duct and its periductal glands but also of the main and interlobular pancreatic ducts and periductal glands in the main pancreatic duct, as well as in pancreatic acinar cells. Ductal staining was fine-granular, and generally present in the supranuclear cytoplasm. Immunoreactivity was abolished by preabsorption. Centroacinar cells and intercalated and intralobular pancreatic ducts did not stain for any enzyme. These findings suggest that some epithelial cells of the large-sized pancreatic duct and its periductal glands express pancreatic alpha-amylase-, trypsinogen-, and lipase-like peptides, as do some epithelial cells of common bile duct and its periductal glands.

Successful retrieval of coil after unintentional embolization of portal vein system: a case report

A rare case of unintentional release of a stainless steel coil into the portal system is reported. The coil migrated into the right portal vein, and the situation was resolved successfully by retrieval of the coil with a homemade loop snare.

Hepatocyte growth factor elevates the activity levels of glycolipid sulfotransferases in renal cell carcinoma cells

Accumulation of sulfoglycolipids associated with markedly elevated activity levels of glycolipid sulfotransferases has previously been demonstrated in the human renal cell carcinoma cell line, SMKT-R3. To elucidate the regulatory mechanisms of sulfoglycolipid synthesis in SMKT-R3 cells, the effects of various growth factors on the metabolic enzymes of sulfoglycolipids were investigated. Hepatocyte growth factor (HGF) significantly increased the activity levels of the sulfotransferases in a dose-dependent manner, but did not change that of arylsulfatase A, which hydrolyzes sulfoglycolipids. Scatchard analysis of 125I-HGF binding to SMKT-R3 cells indicated that the cells expressed high-affinity receptors for HGF with a Kd of 36 pM and 750 sites/cell. Furthermore, metabolic labeling with [35S]sulfate revealed that the addition of HGF to the culture medium of the cells resulted in an increment of sulfoglycolipid synthesis. Therefore, these observations suggest that HGF can function as a regulatory factor in sulfoglycolipid synthesis through the modulation of the sulfotransferase activity levels in renal cell carcinoma cells. In addition, HGF stimulated the proliferation and motility of SMKT-R3 cells, suggesting that HGF has multiple biological activities in renal cell carcinoma cells.

Pancreatic trypsinogen and cathepsin B in human pancreatic carcinomas and associated metastatic lesions

Expression of pancreatic trypsinogen and cathepsin B in 23 surgically resected pancreatic ductal adenocarcinomas was evaluated immunohistochemically, using a monoclonal antibody against human pancreatic trypsinogen and a polyclonal antibody against human cathepsin B. Fifteen of 20 invasive tubular adenocarcinomas (75%) expressed pancreatic trypsinogen in a coarse granular pattern located in the supranuclear cytoplasm of the carcinoma cells. In addition, metastatic lesions, including those in peripancreatic lymph nodes and neural plexuses, expressed pancreatic trypsinogen. In contrast, three intraductal (non-invasive) papillary adenocarcinomas did not express pancreatic trypsinogen. Cathepsin B expression was recognised in 14 of 20 invasive tubular adenocarcinomas (70%) in a fine granular pattern located diffusely in the cytoplasm of the carcinoma cells, while none of the three intraductal papillary adenocarcinomas had detectable cathepsin B. These findings suggest that pancreatic invasive ductal adenocarcinomas express pancreatic trypsinogen and cathepsin B immunoreactive peptides, raising the possibility that pancreatic trypsinogen and cathepsin B may act independently of each other in the process of carcinoma invasion and metastasis, like other different classes of proteases involved in the proteolytic modification of the matrix barrier.

Heparin as an inducer of hepatocyte growth factor

Hepatocyte growth factor (HGF) has mitogenic and unique morphoregulatory functions, and is considered to act as a hepatotrophic and a renotrophic factor for regeneration of the liver and kidney subjected to various insults. We have now obtained evidence that heparin is a potent inducer of HGF production. The addition of heparin to a culture of MRC-5 human embryonic lung fibroblasts increased the HGF concentration in the conditioned medium, in a dose-dependent manner. The maximal stimulation was obtained at 1 microgram/ml heparin and stimulation was 4-fold compared to control cultures. The rate of HGF synthesis in MRC-5 cells, as measured by pulse-labeling with [35S]methionine, and subsequent immunoprecipitation of HGF from both conditioned medium and a cell lysate, was 3-4-fold stimulated by 1 microgram/ml heparin, whereas heparin apparently had no significant effect on the HGF mRNA level. The stimulatory effect of heparin on HGF production was evident in various types of cells, such as MRC-9, IMR-90, and WI-38 human embryonic lung fibroblasts, human skin fibroblasts, HL-60 human promyelocytic leukemic cells and human umbilical vein endothelial cells. In addition to heparin, heparan sulfate also stimulated HGF production, albeit to a lesser extent than heparin; 1.7-fold stimulation with 2 micrograms/ml heparan sulfate. However, other glycosaminoglycans, such as hyaluronic acid, chondroitin sulfate, dermatan sulfate, keratan sulfate, and keratan polysulfate, had no stimulatory effect on HGF production.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatocyte growth factor transforms immortalized mouse liver epithelial cells

Transforming activity of hepatocyte growth factor (HGF) was demonstrated utilizing immortalized but not fully transformed mouse hepatocytes (MLE-10). Rat HGF cDNA, expressed under the control of a cytomegalovirus promoter, was transfected together with the neomycin resistance gene (PSV2neo) into MLE-10 cells by the calcium phosphate method, and propagated G418-resistant colonies were harvested colony by colony. After checking for integration and expression of exogenous HGF, five cell lines (MLE-10-HGF-1-5) were established. Three cell lines transfected with the vector only (MLE-10-CMV-1-3) were also established in the same manner. All MLE-10-HGF cell lines grew much faster than the MLE-10-CMV and original MLE-10 cells in culture and produced large colonies in soft agar, which colony production was blocked by the addition of anti-HGF antibody to the agar. After addition of HGF, original and MLE-10-CMV lines produced colonies in soft agar. The high-HGF-production lines (MLE-10-HGF-4 and -5) also gave rise to tumors within 2 weeks when implanted into the nude mice subcutis. In contrast, all MLE-10-CMV and original MLE-10 cells were negative in these growth assays. A rough parallelism between the level of HGF expression and the growth rate in both soft agar and nude mice subcutis was evident among MLE-10-HGF cell lines. Those with higher HGF production tended to grow in a scattered fashion in culture. High-affinity HGF receptor, HGFR/met, was expressed in MLE-10 and all the derived cell lines. Since HGF and/or HGFR/met gene expression is seen in various tumors and the serum HGF level is elevated in patients with hepatic disease, the present results indicate a possible significance of HGF and its receptor system in carcinogenesis, most probably via autocrine and/or paracrine mechanisms.

Cell density-dependent regulation of hepatocyte growth factor receptor on adult rat hepatocytes in primary culture

The proliferative potential of hepatocytes in the normal intact liver is highly suppressed, but they proliferate actively after liver injury. In this study, adult rat hepatocytes in primary culture were used to study mechanisms controlling hepatocyte growth in liver regeneration. DNA synthesis in hepatocytes cultured at a low cell density was highly stimulated in response to hepatocyte growth factor (HGF), but this stimulatory effect was not so obvious in hepatocytes cultured at a high cell density. In close parallel to the potency of DNA synthesis, the amounts of 125I-HGF specifically bound to hepatocytes cultured at a low cell density were much greater than in high cell density culture. Scatchard plots revealed that change in the specific binding of 125I-HGF was due to change in the number of high-affinity HGF receptors, but without change in the Kd values. Affinity cross-linking of the HGF receptor with 125I-HGF confirmed the higher expression of HGF receptor on hepatocytes cultured at a lower cell density. Since there was no significant change in the expression of c-met mRNA in hepatocytes cultured at different cell densities, the number of cell surface HGF receptors is probably regulated by post-transcriptional mechanisms. We also found that the rates of HGF-induced down-regulation and recovery of HGF receptors on hepatocytes cultured at a low cell density were much faster than in cases of a high cell density.(ABSTRACT TRUNCATED AT 250 WORDS)

[Tuberculin sensitivity to purified protein derivatives from Mycobacterium other than tuberculosis (PPD-B, PPD-Y, PPD-F and PPD-C) and PPDs among patients with mycobacteriosis--cooperative study of the Research Committee for the Mycobacteriosis in Japan]

Purified protein derivatives (PPDs) prepared from M. intracellulare (PPD-B), M. kansasii (PPD-Y), M. fortuitum (PPD-F), M. chelonei subsp. abscessus (PPD-C) and M. tuberculosis (PPDs) were simultaneously used in skin tests on patients diagnosed as having tuberculosis or atypical mycobacteriosis to reveal their specificity, clinical usefulness and immunological status of the patients. The mean diameter of reaction (redness) for patients with M. tuberculosis positive sputum (TB group, n = 71; age, 20-90 yrs) was PPDs, 20.4 mm; PPD-B, 7.9 mm; PPD-Y, 11.7 mm; PPD-F, 0.8 mm; and PPD-C, 0.3 mm. For M. avium complex positive patients (MAC group, n = 100; age, 31-89 yrs), the results were PPDs, 10.9; PPD-B, 16.9 mm; PPD-Y, 10.7 mm; PPD-F, 1.6 mm; and PPD-C, 0.3 mm. The M. kansasii positive patients (K group; n = 8) showed results of PPDs, 12.6 mm; PPD-B, 10.7 mm; PPD-Y, 20.8 mm; PPD-F, 0.5 mm; PPD-C, 0.0 mm. The M. fortuitum positive patients (F group; n = 5) had measurements of PPDs, 5.8 mm; PPD-B, 4.4 mm; PPD-Y, 9.8 mm; PPD-F, 17.8 mm; and PPD-C, 16.0 mm. The patients who were previously M. tbc. positive but presently negative patients (pre. TB group; n = 50) showed the following results: PPDs, 16.6 mm; PPD-B, 7.4 mm; and PPD-Y, 10.9 mm. For the patients who were previously M. avium complex positive (previous MAC group; n = 19), the results were PPDs, 10.4 mm; PPD-B, 9.9 mm; and PPD-Y, 7.7 mm. Also considering their frequency distribution curve, with exception of the previous MAC group, the patient groups showed specificity to the PPD of the bacilli detected. The previous MAC group recorded no significant difference in response to PPDs and PPD-B. Strong cross reactions were observed between PPD-F and PPD-C, and moderate reactions between PPDs, PPD-B and PPD-Y. Cross reactions were scarce between PPDs, PPD-B or PPD-Y and PPD-F or PPD-C. Though it is difficult to distinguish cross-reaction and multiple infections, majority of the patients (72-85%) showed greatest response to the PPD that corresponds with the species of bacilli detected. In conclusion, two or more PPDs applied simultaneously can be of aid in diagnosing mycobacteriosis especially in the early stages of the disease. Also, cross-reactions between atypical mycobacteria and PPDs should be taken into consideration when diagnosing infection caused by M. tuberculosis.

[Transcatheter hepatic arterial embolization for the treatment of blunt hepatic injury]

To examine the indications of transcatheter arterial embolization (TAE) for blunt hepatic injury, angiographic images, CT images and medical records were reviewed. Hepatic angiography was performed in 30 patients with blunt hepatic injury. Sixteen of them who underwent TAE therapy immediately after angiography formed the TAE(+)group, while the 14 patients who were not followed by TAE formed the TAE(-)group. Angiographic extravasation of the contrast medium was confirmed in 14 of 16 patients in the TAE(+)group. On CT scan, the most common finding in the TAE(+)group was a deep hepatic laceration, which was classified as type III according to the criteria of the Japanese association for the surgery of trauma. Hemoperitoneum and fresh hematoma were visualized in most of the TAE(+)group. The preoperative hemodynamics of the TAE(+)group were markedly unstable, but were significantly improved after TAE therapy. No major complications were encountered during or after TAE. These results suggested that TAE was an effective therapeutic procedure for the control of blunt hepatic injury in patients associated with unstable hemodynamics, deep hepatic laceration shown by CT scan and extravasation confirmed by angiography.

[Monostotic fibrous dysplasia of the occipital bone]

A case of monostotic fibrous dysplasia of the occipital bone in a 18-year-old female is described. She was admitted to our hospital with a hard, painless mass (5 x 5 cm) in the occipital region. Neurological examination and laboratory data revealed no abnormalities. Skull x-rays showed a radiolucent lesion with a sclerotic margin in the occipital bone. CT scan revealed an intradiploic multilocular mass separated by bone trabeculae. RI bone scan showed an abnormal uptake in this lesion. T1 and T2 MR image showed an abnormal low-intensity lesion in the occipital region. Operation was performed to verify the nature of the lesion, which was histologically confirmed to be an inactive fibrous dysplasia. Postoperative course was uneventful. Although its occurrence in the occipital bone is uncommon, fibrous dysplasia should be considered in the differential diagnosis of skull tumors.

Negative regulation of hepatocyte growth factor gene expression in human lung fibroblasts and leukemic cells by transforming growth factor-beta 1 and glucocorticoids

Hepatocyte growth factor (HGF), a mesenchymal-derived factor which regulates growth, motility, and morphogenesis of epithelial and endothelial cells, functions as a hepatotrophic and renotrophic factor for regeneration of the liver and kidney. We have now obtained evidence that transforming growth factor-beta 1 (TGF-beta 1) and glucocorticoids are negative regulators for HGF gene expression. When TGF-beta 1 or dexamethasone was added to cultures of MRC-5 human embryonic lung fibroblasts and HL-60 human promyelocytic leukemic cells, the amount of HGF secreted into the culture medium was inhibited to 30-40% of that of control cultures by 10 ng/ml TGF-beta 1 and to 40-50% by 10(-6) M dexamethasone. The inhibitory effect of TGF-beta 1 and dexamethasone on HGF synthesis in MRC-5 cells was additive, thereby suggesting that TGF-beta 1 and dexamethasone exert effects through distinct mechanisms. Hydrocortisone also inhibited HGF synthesis with the same potency as dexamethasone; however, testosterone, estriol, and beta-estradiol had no effect. The rate of HGF synthesis in MRC-5 cells, as measured by pulse labeling with [35S]methionine and subsequent immunoprecipitation, was suppressed to 30-40% of the control with 10 ng/ml TGF-beta 1, and to 30-45% by 10(-6) M dexamethasone. HGF mRNA levels in MRC-5 cells and HL-60 cells were dose-dependently suppressed by TGF-beta 1 and dexamethasone; 10 ng/ml TGF-beta 1 suppressed HGF mRNA levels to 32% and 35% of control culture, respectively, in MRC-5 cells and HL-60 cells, and 10(-6) M dexamethasone suppressed to 43% and 38%, respectively. Thus, TGF-beta 1 and glucocorticoids seem to inhibit HGF synthesis by suppressing the expression of the HGF gene. We propose that a negative regulation of HGF gene expression by TGF-beta 1 or glucocorticoids may be involved in physiological or pathological processes during tissue regeneration.

[Serial MRI findings in neuro-Behçet disease]

Behçet disease is a systemic disorder characterised by the triad of recurrent aphthous ulcers of the mouth, genital ulcers and uveitis. Neurological involvement is estimated at 10-25% in Behçet disease (neuro-Behçet). These include diplopia, pseudobulbar palsy, cranial nerve palsies, cerebeller ataxia, and cerebral and spinal sensory and motor disturbances. A case of neuro-Behçet disease is reported. A 51-year-old man was admitted with TIA attack. He had been suffering from recurrent oral and genital ulcers for several months before admission. Neurological examination on admission revealed poor mental activity, left facial nerve palsy and left hemiparesis. Lumbar puncture showed CSF pleocytosis. CT and MRI revealed multiple lesions in the cerebral hemisphere and the brain stem. CT showed spotty high density areas with perifocal low density areas in the frontal, temporal and parietal lobe which were enhanced with contrast materials. T1 weighted image of MRI revealed iso intensity areas with perifocal low intensity areas which were enhanced with Gd-DTPA in the frontal, temporal and parietal lobes. T2 weighted image revealed low intensity areas with perifocal high intensity areas in the same regions shown in the T1 weighted image. Moreover ring-like enhanced lesions with Gd-DTPA were revealed in the brain stem and corona radiata in the T1 weighted image. After high dose steroid treatment, he showed marked clinical improvement. CSF pleocytosis was normalized and the lesions were gradually reduced in size and were no longer enhanced with Gd-DTPA. MRI findings are well correlated with clinical features.(ABSTRACT TRUNCATED AT 250 WORDS)

[Elemental analysis of hilar and mediastinal lymph nodes in idiopathic pulmonary fibrosis]

Elemental analysis of hilar and mediastinal lymph node tissues was performed to determine whether some inhaled atmospheric elements are implicated in the pathogenesis of idiopathic pulmonary fibrosis (IPF). IPF was divided into two types; typical and atypical, according to our criteria. Lymph nodes were selected as the study material rather than lung tissue, because inhaled elements are concentrated in the hilar and mediastinal lymph nodes, and increase in lung weight due to fibrosis may influence the estimated values of element per unit weight of lung tissue. The hilar and mediastinal lymph nodes collected from 40 IPF cases and 43 non-IPF control cases were examined to determine the concentration of 13 elements in 100 mg dry tissue, using the X-ray fluorescent analysis method. For aluminium, 50 mg dry tissue was examined by an atomic absorption analysis method. Among the 14 elements, Ni in IPF lymph nodes showed a significantly higher level than in control nodes (mean +/- SD: 8.2 +/- 21.3 ppm versus 1.1 +/- 2.1 ppm, respectively. p < 0.01). No difference in each of the examined elements was noted between smokers and non-smokers or between typical and atypical IPF cases. Exogenous elements such as Ni may play a role as triggering substances in the pathogenesis of IPF.

Regulation of cell growth and motility by hepatocyte growth factor and receptor expression in various cell species

Hepatocyte growth factor (HGF), a humoral mediator for regeneration of liver and kidney, possesses multiple biological activities. To investigate target cell specificity and to examine whether multiple actions of HGF are related to properties of the HGF receptor on target cells, we examined the effects of HGF on cell growth and motility and analyzed the HGF receptor in various species of cells. HGF stimulated growth and DNA synthesis of PAM212 (naturally immortalized mouse keratinocytes), Mv1Lu (mink lung epithelia), and A431 (human epidermoid carcinoma) cells, as well as mature hepatocytes, but inhibited those of IM-9 (human B-lymphoblasts). Conversely, HGF had a marked stimulatory effect on cell motility of MDCK (Mardin-Darby canine kidney epithelia) cells, but not on their growth. Also, HGF enhanced the motility of various species of cells, including A431, PAM212, HepG2 (human hepatoma), KB (human epidermoid carcinoma), and J-111 (human monocytes) cells. Scatchard analysis of 125I-HGF binding to hepatocytes indicated that the cells expressed both high- and low-affinity binding sites for HGF with Kd values of 23 and 260 pM, respectively. High-affinity HGF receptor with Kd values of 20-25 pM was detected at 40-720 sites/cell in MDCK, A431, PAM212, Lu99, and IM-9 cells, but not in fibroblasts and hematopoietic cells. In contrast, low-affinity binding sites were detected in all cell lines examined, even in those not responsive to HGF. Northern blots revealed that cells possessing a high-affinity HGF receptor expressed c-MET/HGF receptor mRNA. Therefore, HGF probably regulates both cell growth and motility of various types of epithelial cells and some types of mesenchymal cells. The multiple biological activities of HGF may be exerted through a high-affinity HGF receptor linked to multiple distinct intracellular signaling pathways.

Aberrant left gastric vein directly draining into left portal venous system. A case report

A 66-year-old man with early gastric cancer and liver cirrhosis was diagnosed by preoperative angiography as having an aberrant left gastric vein communicating directly with the left lateral portal vein system. This communication was confirmed during operation for the gastric cancer. Our report is the first of an aberrant left gastric vein showing direct communication with the left portal vein system.

[Function, molecular structure and gene expression regulation of hepatocyte growth factor and its receptor]

Hepatocyte growth factor (HGF), a potent mitogen of mature hepatocytes in primary culture, is composed of 69 kDa alpha-chain with four kringle domains and 34 kDa beta-chain. HGF is currently thought to be a pleiotropic factor, that stimulates the growth and motility of various epithelial cells, and that inhibits the growth of some carcinoma cells. These cells have a single class of high affinity receptor with a dissociation constant (Kd) of 20-30 pM. The maximum number of binding sites (Bmax) was determined to be 100-1500 sites/cell. After 70% partial hepatectomy and unilateral nephrectomy, HGF activity in serum and their tissues increased markedly and HGF receptors of the injured organ rapidly decreased, but not in other normal organs. These results suggest that HGF acts only in a regenerating organ after injury through the control mechanisms governing HGF receptor.

Identification and characterization of "injurin," an inducer of expression of the gene for hepatocyte growth factor

The marked and rapid increase of hepatocyte growth factor (HGF) mRNA in the intact lung of rats after partial hepatectomy or unilateral nephrectomy suggests the existence of a humoral factor mediating a signal of injury to distal organs and may induce the expression of HGF gene in these organs. We have now identified a proteinous factor in the sera of rats with injury of liver or kidney that increases HGF mRNA in the intact lung. When the serum of rats with liver insult caused by partial hepatectomy or ischemic treatment was injected i.p. into normal noninjured rats, it induced a marked HGF mRNA expression in the lung of the recipient rats. The addition of serum from rats with various hepatic or renal injuries to MRC-5 human embryonic lung fibroblasts in culture also led to the induction of HGF mRNA expression, so that the production of HGF by MRC-5 cells after treatment with the sera was remarkably increased in the culture medium. However, serum from the normal intact rat induced no HGF production and no HGF mRNA in the lung in vivo and lung fibroblasts in vitro. This factor, which increases HGF production, was purified greater than 200-fold from sera of CCl4-treated rats. The factor proved to be an acid- and heat-stable protein with an apparent molecular mass of 10-20 kDa in SDS/PAGE. Its activity markedly increased within 3-6 hr in the plasma of rats after various treatments that injured the liver or kidney. These results suggest that the factor specifically appears in the blood of rats with organ injury and may be involved in organ regeneration through the potential to increase the synthesis of HGF. Since the factor seems to mediate various organ injuries, we named it "injurin."

Tissue distribution of hepatocyte growth factor receptor and its exclusive down-regulation in a regenerating organ after injury

Using 125I-labeled hepatocyte growth factor (HGF) as a ligand, we examined the tissue distribution of the HGF receptor in adult rats. Specific binding of 125I-HGF was detected in the plasma membranes of liver, spleen, kidney, lung, adrenal gland, pituitary, and thyroid. Scatchard analysis of HGF binding in liver, spleen, kidney, lung, and adrenal gland revealed the presence of a single class of high affinity receptor with a dissociation constant (Kd) of 20-30 pM. The maximum number of binding sites (Bmax) was determined to be 400-3,000 sites per ng of plasma membrane protein, the highest number being in the liver. Such a wide distribution of a high affinity HGF receptor indicates that HGF may be a multifunctional growth factor, targeting to a variety of organs, and not restricted to liver. After 70% partial hepatectomy, specific binding of 125I-HGF to membranes of the residual liver rapidly decreased, but there was no change in the kidney, lung, and spleen. On the other hand, after unilateral nephrectomy rapid down-regulation of the HGF receptor was clearly evident in the remaining kidney, but not in other organs including the liver. These findings suggest the presence of control mechanisms governing HGF receptor function only in a regenerating organ after injury.

Renotropic functions of hepatocyte growth factor in renal regeneration after unilateral nephrectomy

Hepatocyte growth factor (HGF), a most potent growth factor for mature hepatocytes may act as a trigger for liver regeneration. We reported that HGF strongly stimulates DNA synthesis of rabbit renal tubular cells in secondary culture (Igawa, T., Kanda, S., Kanetake, H., Saitoh, Y., Ichihara, A., Tomita, Y., and Nakamura, T. (1991) Biochem. Biophys. Res. Commun. 174, 831-838). To investigate whether or not HGF is involved in renal regeneration, we examined changes in HGF mRNA, HGF activity, and HGF receptor in the rat kidney following unilateral nephrectomy or treatment with carbon tetrachloride (CCl4). In the intact kidney, the HGF mRNA increased markedly reaching a maximum 6 h after unilateral nephrectomy, followed by an increase of HGF activity at 12 h after the surgery. The marked increase in HGF mRNA and HGF activity was also found in the kidney of rats treated with CCl4. Results of in situ hybridization suggested that cells producing HGF in the kidney are endothelial cells. The number of HGF receptors on renal plasma membranes decreased to 30% of the normal value 12 h after unilateral nephrectomy, with no change in the Kd value. The HGF receptor was greatly diminished 24 h after the operation, and recovery to 60% of the normal level was evident 1 week after the operation. Because the decrease in HGF binding may result from internalization of the HGF receptor, the HGF may bind to its receptor in vivo and act as a mitogen for renal epithelial cells. HGF may function as a renotropic factor during renal regeneration after kidney injury.

[An approach to tuberculosis in newcomers from Asia and Africa]

In recent years, it has been documented that tuberculosis frequently occurs among recently entered foreigners dominantly from Asia. We studied 85 cases admitted to our hospital for active tuberculosis from 1986 to 1990. Many of those cases, we believe, were infected in countries of origin and were reactivated soon after or before entering Japan. In spite of higher rate of involving recurrent cases and resistance to anti-mycobacterial drug agents, chemotherapy has been generally efficient. In some cases, continuance of treatment was difficult because of their illegal stay, misunderstanding of the disease or other problems such as customs and economic difficulties.

Hepatocyte growth factor has potent anti-proliferative activity in various tumor cell lines

Hepatocyte growth factor (HGF) has potent mitogenic activity for mature hepatocytes and various normal epithelial cells. We now have evidence that HGF at 1-10 ng/ml, strongly inhibits the growth of HepG2 hepatocellular carcinoma cells, B6/F1 melanoma cells and KB squamous carcinoma cells. These tumor cells express high affinity receptors for HGF with a Kd of 25-28 pM, similar to findings with hepatocytes. HGF at 1-100 ng/ml had no significant cytolytic effect on tumor cells. Therefore, the anti-proliferative effect of HGF on tumor cells seems to be cytostatic, not cytolytic. As HGF apparently has bidirectional effects on cell growth, the possibility that it can serve as an anti-tumor agent merits attention.

[A case of mediastinal mature teratoma with elevated of CA 19-9 in tumor fluid]

A 20-year-old female was diagnosed as mediastinal tumor and admitted to our hospital for the operation. Among the preoperative examinations, the serum level of CA 19-9 was within normal limits. The fluid inside the cystic tumor which was removed during the operation showed high levels of CA 19-9. We discussed the relationship between CA 19-9 and cystic lesions. Histopathological study revealed that CA 19-9 was produced in only epithelial cell of the cystic lesion. And we speculated that examination of serum CA 19-9 helps the diagnosis of cystic lesions.

[Value of "additional arterial embolization" to bilateral internal iliac TAE in patients with severe pelvic fractures]

Transcatheter arterial embolization (TAE) of the bilateral internal iliac arteries has been shown to be of great value in controlling retroperitoneal massive hemorrhage associated with pelvic fractures. It has recently been reported, however, that TAE of only the bilateral internal iliac arteries sometimes fails to stabilize the patient's hemodynamics. The purpose of the present study was to evaluate "additional arterial embolization" to the bilateral internal iliac TAE in hemodynamically unstable cases. Sixty-eight patients who underwent emergency TAE following severe pelvic fractures were reviewed. Additional arterial embolization of the lumbar arteries in four patients, middle sacral arteries in two and inferior epigastric artery in one was carried out following bilateral internal iliac TAE. The damage to these arteries was associated with fractures of the lumbar costal process, sacrum, pubis, etc. The patients were in stable condition after the procedure, and no significant complication was experienced. When fractures and dislocations of the above-mentioned bones are seen on plain X-ray films and arterial bleeding is identified by angiography, additional embolization of the arteries should be performed immediately.

Hepatocyte growth factor is a potent stimulator of human melanocyte DNA synthesis and growth

Hepatocyte growth factor (HGF) is a potent mitogen for adult rat hepatocytes in primary culture. HGF stimulates growth and DNA synthesis of normal human epidermal melanocytes in culture. The maximal stimulation of DNA synthesis by 4.0-fold occurred with 10 ng/ml HGF. This stimulatory effect was additive with both acidic and basic fibroblast growth factors, while it was inhibited by transforming growth factor-beta 1. Melanocytes expressed a single class of specific, high-affinity receptors for HGF with a Kd of 22 pM and approximately 120 receptors/cell. Thus, HGF is a potent mitogen for normal human epidermal melanocytes.