Bovine serum albumin-doxorubicin conjugate overcomes multidrug resistance in a rat hepatoma

A bovine serum albumin-conjugated doxorubicin via the glutaraldehyde bridge (BSA-DXR conjugate) showed potent dose-dependent inhibition of cell growth against daunorubicin-resistant AH66 (AH66DR) cells as well as parental AH66 (AH66P) cells in vitro as compared to treatment with DXR or BSA-glutaraldehyde conjugate without DXR (BSA-GA). In the culture of AH66DR with BSA-DXR conjugate, drug accumulation in the AH66DR cells increased as a function of time up to 24 h reaching approximately the same drug level as AH66P cells treated with DXR. The intracellular accumulation of the BSA-DXR conjugate was inhibited by the addition of ammonium chloride, while that of DXR alone was not inhibited. Intracellular DXR was effluxed rapidly from AH66DR cells, but BSA-DXR conjugate or pharmacologically active DXR adduct remained in the cells at a relatively high concentration over a 36-h time period. The life-prolonging effect of the conjugate was assessed using rats inoculated i.p. with AH66P or AH66DR. The rats were treated with the BSA-DXR conjugate, DXR, a mixture of DXR with BSA, or BSA-GA by either the i.p. or i.v. route. Treatment with DXR had no significant surviving effect as compared to that with saline in AH66P-bearing rats. By contrast, BSA-DXR conjugate showed a significant life-prolonging effect as compared with DXR alone in the same degree both in AH66P- and AH66DR-bearing rats. BSA-GA did not show any toxicity in vivo as well as in vitro. These results indicate that the BSA-DXR conjugate allows DXR to escape from the multidrug resistance mechanism.

[Angiotropic lymphoma presenting with subacute dementia: treatment with combination chemotherapy (CHOP) based on antemortem diagnosis--a case report]

We report a 64-year-old male with angiotropic lymphoma. He developed subacute dementia with right hemiparesis. Laboratory abnormalities included elevated serum lactic dehydrogenase (LDH) (715 U/l) erythrocyte sedimentation rate (38 mm/hr) and CSF protein (90 mg/dl). Precontrast MR imaging of the brain demonstrated lesions involving the left internal capsule, subcortical white matter in the right frontal lobe and splenium within the atrophic corpus callosum. A brain biopsy revealed intravascular lymphoid cells, strongly suggestive of angiotropic lymphoma. By combination chemotherapy (CHOP), serum LDH and CSF protein normalized through the patient remained demented. He died of bronchopneumonia about 2 years and 5 months after the onset. Coronal sections of the brain showed infarct in the left internal capsule as well as markedly thin corpus callosum with necrotic lesions involving both the genu and splenium. Microscopic examination showed many small vessels occluded by lymphoma cells (B-lymphocyte) predominantly in the corpus callosum, cerebral white matter, thalamus, midbrain, medulla oblongata, thoracic and lumbar segments of the spinal cord. By combination chemotherapy, our patient survived longer than most of previous patients with angiotropic lymphoma. An early diagnosis and subsequent combination chemotherapy may improve neurological manifestations, and make possible longer survival in angiotropic lymphoma.

Stimulation of DNA synthesis in osteoblast-like MC3T3-E1 cells by Bordetella bronchiseptica dermonecrotic toxin

We investigated the effects of Bordetella bronchiseptica dermonecrotic toxin on DNA synthesis in MC3T3-E1 cells. The rate of [methyl-3H]thymidine incorporation increased in the toxin-treated cells more than 24 h after addition of the toxin under the serum-starved conditions. This effect was dependent on the toxin concentration ranging from 0.3 to 3 ng/ml and was eliminated by aphidicolin and hydroxyurea, inhibitors for DNA replication. In the toxin-treated culture, the number of cells did not increase but polynucleated cells appeared and their number increased to ca. 50% of the total number of cells 6 days after the toxin addition. From these results, we concluded that the toxin stimulates DNA replication in MC3T3-E1 cells without cell proliferation.

Effects of sex hormones on induction of intestinal metaplasia by X-irradiation in rats

The influence of sex hormones on induction of intestinal metaplasia was examined in 5 week old Crj: CD (SD) rats of both sexes. At the age of 4 weeks, the animals were gonadectomized and given testosterone or dimethyl estradiol (DES). One week after operation, they were irradiated with two 10 Gy doses of X-rays to the gastric region at a 3 day interval for a total of 20 Gy. At the termination of the experiment, 6 months after the alkaline phosphatase (ALP) positive foci in males was significantly higher than in females, in orchidectomized males or orchidectomized plus DES treated rats (P < 0.01). On the other hand, the incidence of intestinal metaplasia with ALP-positive foci in normal females appeared lower than in ovariectomized females (P < 0.01), and was increased in rats by treatment with testosterone or decreased by DES. Numbers of foci of intestinal metaplasias with Paneth cells and total numbers appeared to increase in males treated with DES. The results suggested a promoting role for testosterone in the development of ALP positive lesions and indicated considerable heterogeneity between intestinal metaplasia subtypes.

[Clinical effect and characteristics of low dose leucovorin and high dose 5-FU therapy in patients with recurrent gastric cancer--a new method of biochemical modulation]

The biochemical modulation of 5-fluorouracil (5-FU) and leucovorin (LV) has resulted in a remarkable increase of the response rate in patients with colorectal cancer. Recently, in the treatment of gastric cancer this biochemical modulation has been introduced into clinical practice and has also achieved good antitumor activity. A review of the literature indicates that 5-FU/LV therapy for gastric cancer is effective only when LV is administered at high doses (200 mg-500 mg/m2), and the efficacy of low dose LV (20 mg/m2) administration with the combination of high dose 5-FU is still unknown. Thirty-five patients with measurable recurrent gastric cancer received low dose LV and high dose 5-FU for 4 days. The schedule was as follows: iv injection of low dose leucovorin (20 mg/m2) and from one hour later 2-hour infusion of high dose 5-FU (700 mg/m2). This new treatment for recurrent gastric cancer achieved a response rate of 40.0%, and 80.0% of the patients with pronounced palliative effects measured as recurrence-related symptoms. It is very rare for 7 out of 8 patients (87.5%) to be relieved of obstructive jaundice, and we now prefer this therapy to percutaneous transhepatic biliary drainage in patients with jaundice. The toxicity of this biochemical modulation is leukopenia, stomatitis and diarrhea, and the number of patients with toxicity over grade 3 was 5 (14.3%). There was no treatment-related death.

A new type of congenital dysfibrinogen, fibrinogen Bremen, with an A alpha Gly-17 to Val substitution associated with hemorrhagic diathesis and delayed wound healing

We have identified a new type of A alpha Gly-17 to Val substitution in a congenital dysfibrinogen, fibrinogen Bremen, derived from a 15-year-old boy having manifested easy bruising and delayed wound healing. The functional abnormality was characterized by altered fibrin monomer polymerization, which became evident by increasing the salt concentration and pH. A synthetic tetrapeptide with a sequence of the amino-terminal segment of normal fibrin alpha-chain, Gly-Pro-Arg-Val, substantially inhibited polymerization of both normal and the patient-derived fibrin monomers. A synthetic tetrapeptide with the Bremen type sequence of Val-Pro-Arg-Val inhibited polymerization of the patient's fibrin monomers partially at a peptide: fibrin monomer molar ratio of 4,000:1, and that of normal one at a much higher ratio of 10,000:1. Likewise, a synthetic peptide Ala-Pro-Arg-Val with a replacement of the Gly residue by another aliphatic amino acid Ala inhibited similarly the patient's fibrin monomer polymerization. Thus, the hypothetical two-pronged socket-like structure consisting of the alpha-amino group of the amino-terminal Gly and the guanidino group of an Arg at position 3 of the normal fibrin alpha-chain seems to be restored considerably in the mutant fibrin alpha-chain at low ionic strengths and pH's, despite the replacement of the amino-terminal Gly by another aliphatic amino acid Val.

A possible prototype of multifocal recurrence after liver resection of hepatocellular carcinoma: report of a case

The clinical course of a 68-year-old male with HCC is herein reported. In addition to two tumor nodules detected preoperatively, the resected surgical specimen disclosed macroscopically invisible tumor-cell clusters as well as intrahepatic metastatic foci. These clusters had no clear border and were more basophilic with small-sized cells, high cellularity, and a higher nuclear/cytoplasm ratio, which was suggestive of early HCC with a form of de novo occurrence. The postoperative course, characterized by an early recurrence of small nodules in the remnant liver suggested the presence of a similar invisible tumor mixture at the time of operation. This case can thus be regarded as a prototype of the multifocal recurrence type.

[Central nervous system metastasis from lingual carcinoma: report of a case]

A rare case of lingual carcinoma which metastasized to the brain is reported. A 66-year-old man was referred to our department on April 23, 1991, with complaints of memory disturbance and mild left motor weakness of one month's duration. The patient had been discharged from the Department of Otolaryngology of our hospital 9 months before, after undergoing radical neck dissection and chemotherapy (THP, CDDP, PEP) for his lingual cancer with metastases to the cervical lymph nodes and the lung. On admission to our department, the patient complained of mild frontalgia. Neurological examination showed memory disturbance, change of character, mild left hemiparesis and urinary incontinence. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a well circumscribed mass in the right frontal lobe associated with midline shift toward the left. Systemic Gallium-67 scintigraphy demonstrated an abnormal uptake in the right frontal region, but no abnormal uptake was seen in the neck and the lung. The most likely diagnosis was thought to be metastasis of lingual cancer. The patient underwent tumor removal 10 days after admission. A histological examination of the tumor specimen revealed metastatic anaplastic cell carcinoma, indicating a metastasis from lingual carcinoma. After postoperative radiotherapy (total 60 Gy), the patient was discharged without neurological deficit. Central nervous system metastasis from lingual carcinoma is quite rare. To the best of our knowledge, only two such cases have been reported. We report another rare case of solitary brain metastasis from lingual carcinoma and review the pertinent medical literature.

Increase in ubiquitin conjugates dependent on ischemic damage

Insoluble ubiquitin conjugates (UC) in the mitochondrial fraction of the gerbil cortex were analyzed following transient forebrain ischemia. At 1 h of reperfusion after 2-10 min of ischemia, UC increased as the duration of ischemia was prolonged. Pre-treatment with pentobarbital, rather than post-treatment immediately after recirculation, reduced the increase of UC at 1 h of reperfusion following 5 min of ischemia. Pentobarbital had no effect on in vitro ubiquitination of heat-denatured lysozyme by the extract of gerbil cortex. These results suggest that increase in UC is dependent on ischemic damage and pentobarbital attenuates the increase of UC by relieving injury during ischemia.

Immune recognition of hormonogenic sites of human thyroglobulin: studies of Graves' sera and a murine monoclonal antibody with thyroid hormone antibody activity

We synthesized four peptides (HTg-1, 1-10; HTg-2, 2547-2558; HTg-4, 2592-2603 and HTg-6, 2737-2748) and two peptides (HTg-3, 2582-2591 and HTg-5, 2687-2694) with or without hormonogenic acceptor tyrosine of human thyroglobulin (hTg). They were iodinated with 127I or 125I. 127I-labeled peptides were tested for their ability to displace 125I-T4 binding to thyroid hormone autoantibodies (THAA) in two cases of Graves' disease and to a murine anti-hTg monoclonal antibody with anti-T4 activity (mAb). 125I-labeled peptides were tested for the direct binding to the aforementioned antibodies. None of the peptides displaced 125I-T4 binding to THAA or to a mAb, or exhibited increased binding to THAA and to a mAb. 125I-T4 binding to a mAb was equally displaced by hTgs obtained from a normal thyroid gland (NTg) and a case of Hürthle cell adenoma with undetectable iodine content (CTg). 125I-T4 binding to serum gamma globulin in each patient's serum was completely displaced by NTg, but CTg displaced 125I-T4 binding 2% and 5% in Case 1 and Case 2, respectively. It was speculated that the mAb recognizes a topological epitope around the hormonogenic site of hTg, while that of THAA in our two cases recognizes only T4 or an iodine dependent topological epitope(s) of hTg.

[Dermoid cyst in the fourth ventricle associated with Klippel-Feil syndrome]

Dermoid cysts in the central nervous system are often associated with various congenital disorders, especially dermal sinus and spina bifida. We report a case of dermoid cyst in the fourth ventricle associated with Klippel-Feil syndrome. A 47-year-old man with a long history of headache had been known to have a cystic lesion in the posterior fossa for 12 years. When he was referred to our hospital with complaints of transient tetraparesis, he showed bilateral cerebellar ataxia and minimal left hemiparesis. Furthermore, he was noted to have a webbed neck with a low hairline and facial asymmetry. CT and MRI showed multiple cerebral infarctions as well as a mass lesion in the posterior fossa. Cervical roentgenogram showed a fusion of C 2 and C 3 vertebrae. The tumor was totally removed via a suboccipital approach, and the diagnosis was a dermoid cyst. The present patient had not only dermoid cyst and Klippel-Feil syndrome but also hypertrophy of the zygomatic bone. The pathogenesis of the Klippel-Feil syndrome is presumed to be an intrauterine defect, with a failure of segmentation of mesodermal somites. The zygomatic bone is also derived from the mesoderm somites at early fourth week, too. From these points of view, the disturbance in the mesoderm before the fourth week of gestation might have played an important role in causing a dermoid cyst.

[Advanced breast cancer with onset of multi-organ metastases successfully treated with combined loco-regional therapies: a case report]

A 56-year-old woman was referred to Shizuoka General Hospital on April 17, 1992, because of progressive jaundice and massive pleural effusion. A thorough work-up revealed the diagnosis of advanced left breast cancer complicated with direct invasion of the thoracic wall, pleural carcinomatosis, multiple liver and bone metastases and obstructive jaundice due to the hilar mass. From a prognostic point of view, we scheduled the treatment course as follows. First, we treated the chief complaints. After emergency drainage and chemo-adhesive therapy of the pleural lesion, percutaneous biliary drainage and radiotherapy were done for obstructive jaundice, followed by internal drainage with self-expandable metallic stents. For the primary cancer of the left breast, standard mastectomy was performed following 57 Gy of radiotherapy. MPA was also administered because estrogen-receptor was positive on the histological examination of the resected specimen. To complete the multi-disciplinary treatment, we implanted a vascular access percutaneously via the left femoral artery and started intermittent hepatic arterial infusion chemotherapy on an outpatient basis. The patient was discharged on the 123rd hospital day and is well and active without any symptom 9 months thereafter.

Monoclonal-antibody against Doxorubicin (dxr) - some characteristics and utilization for dxr-immunoassay

To establish a rapid, specific, sensitive and simple assay method for doxorubicin (DXR) in body fluid, monoclonal antibodies (MAbs) against DXR were generated by immunizing mice with keyhole limpet hemocyanin-DXR conjugate, cell fusion, and a one step, time saving screening ELISA method using aminoplate-coupled DXR via a glutaraldehyde bridge as solid phase antigen. Inhibition ELISA for DXR-immunoassay was established using anti-DXR MAb of the best producer (2E9) and aminoplate-coupled DXR as antigen and DXR ranging from 50 pg to 50 ng in the body fluid or in the cell extract could be detected. MAb 2E9 cross-reacted to various degrees to anthracycline compounds, such as some DXR analogues and derivatives, but did not recognize anthracene and anthraquinone structures.

Cytotoxicity of T cells for cerebral endothelium in multiple sclerosis

We investigated the cytotoxic effect of peripheral blood T cells on cerebral endothelium in patients with MS. We examined in vitro the damage to 51Cr-labelled dissociated human brain endothelial cells produced by mitogen-stimulated T cell lines from patients with MS and controls. Endothelial targets were lysed by T-lymphocytes from patients with acute relapsing MS during an exacerbation at every target-effector cell ratio tested compared with controls (P < 0.001). The percentage of endothelial targets lysed was not significantly increased by incubation with T cells from patients with acute relapsing MS in remission and chronic progressive MS, compared with that of normal subjects. Relapsing MS patients during an exacerbation had significantly higher interleukin-1 (IL-1)-alpha concentrations in cultures of targets with effector cells than normal subjects (P < 0.02). Experiments of major histocompatibility complex (MHC)-restricted cytotoxicity in MS demonstrated incomplete blocking of specific lysis by either anti-MHC class I or class II monoclonal antibody (mAb). These results indicate that cytotoxicity of T cells for cerebral endothelial cells may play a role in the initiation of immune response in acute relapsing MS during an exacerbation which appears to cause an increase in blood-brain barrier (BBB) permeability.

[Transplantation of basal forebrain cells of fetal rats into the subarachnoid space: improvement of disturbance of passive avoidance memory due to injury of basal forebrain]

The memory disturbance of senile dementia of Alzheimer type has been thought to associate with marked degeneration and loss of cholinergic neurons of the basal forebrain (nucleus basalis of Meynert, NBM). Electrical or chemical destruction of the NBM causes memory deficits in rats. After unilateral lesioning of the NBM in adult rats with excitotoxic amino acid, kainic acid, basal forebrain cells of fetal rats were transplanted through a microsyringe needle, the tip of which was transcortically inserted to the subarachnoid space. Eight weeks after the transplantation, passive avoidance response test was performed, and the response was compared with those of non-transplanted lesioned rats and of non-operated control rats. Although acquisition impairment did not improve, retention impairment was significantly ameliorated in the transplanted rats. Transplanted fetal neurons survived and grew very well over the cortical surface and exhibited facilitated neuritic elongation (acetylcholinesterase staining), but the neurites penetrating the intact pia mater were not verified. Choline acetyltransferase-immunoreactive neurons were found along the needle tract as well as in the subarachnoidal graft. The innervated neurites from the needle tract were rare. The results indicate that the re-innervation from the graft to the host cortex is not necessarily indispensable for improvement of memory deficit due to injury of the NBM. We suppose that the diffusional supply of neurotransmitters and/or their synthetic enzymes and some kinds of neuronotrophic factors is more important. Moreover, we emphasize the participation of astroglias, which are simultaneously transplanted with neurons, in production of neuronotrophic factors.

Both the SH2 and SH3 domains of human CRK protein are required for neuronal differentiation of PC12 cells

Human CRK protein is a homolog of the chicken v-crk oncogene product and consists mostly of src homology region 2 (SH2) and SH3, which are shared by many proteins, in particular those involved in signal transduction. SH2 has been shown to bind specifically to phosphotyrosine-containing peptides. We report here that both SH2 and SH3 are required for signaling from CRK protein. Microinjection of the CRK protein induced neurite formation of rat pheochromocytoma cell line PC12. This activity was abolished by mutation of the CRK protein in either SH2 or SH3. The neuronal differentiation induced by the CRK protein was blocked by an excess amount of peptides containing CRK SH3. Moreover, we identified three proteins, of 118, 125, and 136 kDa, which bound specifically to CRK SH3. The CRK-induced neuronal differentiation was also suppressed by monoclonal antibodies against either CRK SH2 or p21ras. These results suggest that both SH2 and SH3 of the CRK protein mediate specific protein-protein binding and that the resulting multimolecular complex generates a signal for neurite differentiation through activation of p21ras.

Molecular defect in factor IX Tokyo: substitution of valine-182 by alanine at position P2' in the second cleavage site by factor XIa resulting in impaired activation

Utilizing polymerase chain reaction and directly sequencing the amplified exon 6 of the factor IX gene derived from a mild hemophilia Bm patient, we have identified a T to C mutation at nucleotide 20,525. This point mutation predicted a Val182 to Ala substitution in the abnormal factor IX molecule, designated as factor IX Tokyo. The patient manifested a low factor IX activity and a moderately prolonged ox-brain prothrombin time but a normal factor IX antigen level in plasma. Immunopurified factor IX derived from the patient was found to have a normal molecular weight but a reduced specific activity (23% of normal). Limited proteolysis by activated factor XI or by a snake venom-derived factor X-activating enzyme was considerably delayed, indicating the presence of structural alteration(s) most probably at or near the second enzyme-cleavage site. Once activated, however, factor IXa Tokyo was able to activate factor X normally and was inactivated by antithrombin III also in a normal fashion. The structural model of factor IXa and a docking model of factor IX and activated factor VII (factor VIIa) suggested that the Val182 to Ala substitution would not affect the local conformation of the catalytic domain. This mutation would rather loosen the fitness of the molecule into the substrate-binding pocket of factor VIIa due to a shorter side chain of the Ala substitution at the P2' position of the second cleavage site.

Increased levels of circulating intercellular adhesion molecule-1 in multiple sclerosis and human T-lymphotropic virus type I-associated myelopathy

We evaluated the presence of soluble intercellular adhesion molecule-1 (sICAM-1) antigen in the sera of patients with multiple sclerosis and human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) using an enzyme-linked immunosorbent assay. Patients with multiple sclerosis in the active phase had higher sICAM serum levels than did control subjects (p < 0.01). In addition, a significantly increased serum level of sICAM-1 was found in patients with HAM (p < 0.001). Furthermore, we found a positive correlation with HAM sICAM-1 and tumor necrosis factor-alpha levels in the sera of patients with multiple sclerosis in the active phase (r = 0.88, p < 0.01) and in those with HAM (r = 0.86, p < 0.01). These results suggest that serum sICAM-1 may be related to clinical activity in patients with multiple sclerosis and the detection of sICAM-1 could be useful as a marker of inflammatory disease.

Lung cancer incidence rate for male ex-smokers according to age at cessation of smoking

Lung cancer incidence rate after the cessation of smoking was assessed for male ex-smokers according to the age at cessation, using the results from a case-control study for ex-smoker versus continuing smoker, and the lung cancer incidence rate function for continuing smoker estimated from Japan Vital Statistics and the "Six-prefectural Cohort Study" in Japan. This hospital-based case-control study consisted of 776 lung cancer cases (553 current smokers and 223 ex-smokers) and 772 controls (490 current smokers and 282 ex-smokers) who started smoking at ages 18-22. The odds ratio of developing lung cancer for ex-smokers compared to continuing smokers according to years since the cessation of smoking was estimated for four age groups (55-64, 60-69, 65-74 and 70-79). Given that the number of years since cessation of smoking is the same, reduction of the odds ratio appeared to be greater for the younger age group than for the older age group, reflecting the shorter period of exposure for the younger age group. Lung cancer incidence rate (per 100,000) was assumed to be expressed by the following function; 1.7 x 10(-5) x (age -24.3) for continuing smokers and 0.15 x 10(-5) x (age) for nonsmokers. Lung cancer incidence rate among ex-smokers according to years since cessation was then estimated to be the above function multiplied by the odds ratio from the case-control study for each age group. In contrast to the greater reduction of the odds ratio among younger ex-smokers, reduction of the incidence rate, in terms of rate difference, was considerably greater for older ex-smokers due to a high incidence rate of lung cancer for older continuing smokers. This indicates that the absolute magnitude of reduction of the lung cancer incidence rate after cessation of smoking is greater for older ex-smokers, although the relative magnitude of reduction is greater for younger ex-smokers.

Insulin stimulates association of insulin receptor substrate-1 with the protein abundant Src homology/growth factor receptor-bound protein 2

Insulin activates the ras proto-oncogene product p21ras (Ras) by stimulating conversion of the inactive GDP-bound form of Ras to the active GTP-bound form. The protein ASH (for abundant Src homology) (Matuoka, K., Shibata, M., Yamakawa, A., and Takenawa, T. (1992) Proc. Natl. Acad. Sci. U. S. A. 89, 9015-9019) is composed of one Src homology (SH)2 and two SH3 domains and highly homologous to the Caenorhabditis elegans protein sem-5 that couples a tyrosine kinase to a Ras protein. We have studied an interaction of ASH with insulin-stimulated tyrosine-phosphorylated proteins in Chinese hamster ovary cells overexpressing human insulin receptors (CHO-HIR cells). In an anti-ASH (alpha ASH) immunoprecipitates, we detected a 170-kDa phosphoprotein that was recognized by an anti-phosphotyrosine antibody and an anti-insulin receptor substrate 1 antibody (alpha IRS-1) from the insulin-stimulated [32P]orthophosphate-labeled CHO-HIR cells. We failed to detect the tyrosine phosphorylation of the protein ASH. These data suggested that insulin stimulates IRS-1.ASH complex formation in intact cells. Incubation of an ASH fusion protein with the lysates of insulin-stimulated CHO-HIR cells revealed that the fusion protein of ASH was able to bind the tyrosine-phosphorylated 170-kDa protein that was recognized by alpha IRS-1. We also demonstrated that fusion protein of ASH was able to bind the fusion protein of tyrosine-phosphorylated IRS-1 fragments, suggesting that ASH is able to bind tyrosine-phosphorylated IRS-1 directly. These data suggest that IRS-1.ASH complex formation may play a role in coupling the insulin receptor kinase to a Ras signaling pathway. Furthermore, we observed an insulin-stimulated phosphatidylinositol (PI) 3-kinase activity in alpha ASH immunoprecipitates, suggesting the formation of an ASH.IRS-1.PI 3-kinase complex. This complex formation was detected as early as 10 s after insulin stimulation in intact CHO-HIR cells. This is the first report that supports the notion that IRS-1 binds several signal transducing molecules containing SH2 domains, thus serves as an SH2 docking protein that transduces insulin's signal multidirectionally.

In vivo glucose metabolism in obese and type II diabetic subjects with or without hypertension

This study examined whether the presence of hypertension, an insulin-resistant condition, exacerbates the defect in insulin action observed in obesity and type II diabetes mellitus. Glucose metabolism in the basal state and in response to insulin was quantitated by using the euglycemic insulin (20 mU.min-1 x m-2) clamp in combination with 3-[3H]glucose infusion and indirect calorimetry in 20 obese nondiabetic subjects (10 hypertensive and 10 normotensive), 26 type II diabetic subjects (13 hypertensive and 13 normotensive), and 11 normal nondiabetic subjects. The two groups of obese subjects and the two groups of diabetic subjects were matched for sex, age, race, body mass index, and fat distribution. Both in the basal state and during insulin infusion, glucose disposal rates (total, oxidative, and nonoxidative) were similar in obese subjects with or without hypertension. Compared with control subjects, both groups of obese subjects were markedly insulin resistant. Similarly, type II diabetic individuals, whether normotensive or hypertensive, were equally insulin resistant. The severity of insulin resistance was nearly identical in obese and diabetic groups. In diabetic subjects, the inhibitory effect of insulin on hepatic glucose output, lipolysis, and lipid oxidation was blunted compared with normal subjects. In obese subjects the ability of insulin to inhibit lipolysis and lipid oxidation was impaired. However, hypertension did not alter the suppressive effects of insulin on hepatic glucose production, plasma free fatty acid levels, or lipid oxidation in either obese or type II diabetic subjects. These results indicate that hypertension does not confer a greater severity of insulin resistance than that already is present in obesity and type II diabetes mellitus.

[A case of interstitial pneumonia of polymyositis-dermatomyositis with various pathological findings in open lung biopsy]

A 60-year-old woman was admitted to our hospital with a two month history of dry cough and dyspnea on exertion. A chest roentgenogram revealed diffuse interstitial shadows with a reduction of lower lung volume. Laboratory examinations revealed an increase in CPK and aldolase. There was decreased proximal muscle power, and the findings of a biopsy of the right deltoid were compatible with polymyositis. Myositic symptoms were stable, but the respiratory symptoms worsened, and an open lung biopsy was performed for diagnosis and to determine the best treatment. The histological findings of biopsy materials demonstrated active interstitial pneumonia complicated by cellular interstitial pneumonia, bronchiolitis obliterans organizing pneumonia, usual interstitial pneumonia and lymphoid hyperplasia. The patient responded well to adrenocorticosteroid and immunosuppressive therapy, and is now attending as an out patient. It is well known that PM-DM can be associated with interstitial pneumonia, and this complication is an important prognostic factor clinically. The pathological patterns of interstitial pneumonia in PM-DM may be divided into usual interstitial pneumonia and bronchiolitis obliterans organizing pneumonia. Furthermore, it is well documented that these patterns are concurrent with the response to adrenocorticosteroid and prognostic factors. However, our case of PM-DM, in which various patterns such as rheumatoid arthritis (RA) were pathologically revealed, cannot be considered as having uniform pathological pattern. We consider that pulmonary pathological patterns of PM-DM are very varied, as with RA. It is a very important to evaluate the nature of these patterns and the subsequent clinical course in PM-DM with interstitial pneumonia.

Assay of vitamin B6 in human plasma with graphitic carbon column

A high performance liquid chromatographic (HPLC) procedure for measuring pyridoxal-5'-phosphate (PLP) and certain forms of B6 vitamers in plasma is presented here. This HPLC procedure consisted of a single graphitic carbon column with a fluorescence detector employing an isocratic eluent (15% acetonitrile: 1% perchloric acid: 0.05% sodium bisulfite). The graphitic carbon column is useful in acidic eluent without deteriorization. The relatively low fluorescent intensity of PLP under acidic conditions is improved by its derivatization with bisulfite in the eluent during chromatographic separation. Using this procedure, the detection limit of PLP is 50 fmol, and an aliquot of 5-50 microL of human plasma is required giving satisfactorily precise results within 5 min. We applied this method to the determination of PLP and certain B6 vitamers in human plasma after oral supplementation of pyridoxine.