Antithrombin and thrombolytic effects of a new antithrombin agent: angioscopic and angiographic comparison with heparin or batroxobin

The antithrombotic effect of three different types of antithrombotic agents (antithrombin:argatroban, heparin, defibrinogenating agent:batroxobin) were evaluated in canine coronary and iliac arteries. An occlusive thrombus was produced by balloon injury. One of the three agents was infused intravenously at 1 hour after thrombus formation (heparin 250 U/kg, argatroban 0.5 mg/kg, batroxobin 0.5 U/kg) and the effect of thrombus size reduction was evaluated. On the contralateral side of the iliac artery, the preventive effect of these agents on thrombus formation was evaluated after balloon injury. In the iliac artery, angioscopic percent area obstruction by the thrombus before and 60 minutes after treatment reduced from 69% to 32% in the argatroban group, and from 64% to 51% in the batroxobin group (P < 0.0001 and P < 0.05, respectively). No significant change was observed in the heparin group. Angiography demonstrated the same trend. The percent area stenosis with thrombus at 60 minutes following balloon injury was 0.75% in the argatroban group, 18.9% in the heparin group (P < 0.05 vs argatroban), and 12.9% in the batroxobin group. Thrombus size at the treated site was smaller than that at the control site in all three groups (P < 0.05 vs control). In the coronary artery, angioscopic percent area obstruction by the thrombus before and 60 minutes after treatment reduced from 84% to 53% in the argatroban group, and from 86% to 68% in the batroxobin group (P < 0.0001 and P < 0.05, respectively). No significant change was observed in the heparin group. Angiography also demonstrated the same trend. The activated partial thromboplastin time (APTT) was prolonged to 189% of the control value with argatroban and to 1253% of the value with heparin (P < 0.0001). Fibrinogen was markedly reduced with batroxobin. These results showed that both the antithrombin agent and the defibrinogenating agent have a preventive effect on thrombus formation and the effect on thrombus size reduction, without marked prolongation of the APTT.

IL-1 beta regulates the expression of the Gi2 alpha gene via lipid mediators in guinea pig tracheal muscle

When isolated guinea pig muscle preparations were incubated with human recombinant IL-1 beta, mRNA level of Gi2 alpha but not of Gs alpha increased in a time and dose dependent manner. The increase was partially blocked by inhibitors of lipoxygenase (NDGA) and cyclooxygenase (indomethacin) and PAF antagonist (SC47014A), while U46619 (thromboxane A2 mimetic), LTD4, 15-HETE and PAF partially mimicked it. The IL-1 beta induced Gi2 alpha expression was almost completely inhibited by anti-phospholipase A2 antiserum, whereas preimmune serum had no apparent effects. From these observations, we suggest that IL-1 beta first induces the synthesis and release of Type II inflammatory phospholipase A2, which in turn stimulates the expression of Gi2 alpha gene via production of various lipid mediators.

[Nontraumatic femoral head necrosis: classification of bone scintigraphic findings and diagnostic value of SPECT following planar imaging]

This study was conducted to determine bone scintigraphic findings in nontraumatic femoral head avascular necrosis and diagnostic value of SPECT imaging following a conventional planar imaging. Forty-three femoral heads in twenty-six cases with idiopathic femoral head necrosis (n = 2), systemic lupus erythematosus (n = 22), aplastic anemia (n = 1), and renal transplantation (n = 1) were studied. The diagnosis for femoral head necrosis was based on magnetic resonance imaging as well as other diagnostic studies in all cases. Scintigraphic findings of planar and SPECT images were classified into six categories: normal (N); cold or decrease (C); partial increase with cold or decrease (PH+C); ring-like increase with a cold center (RH+C); partial increase (PH); diffuse and/or irregular increase (DH). Avascular necrosis was confirmed in twenty-four femoral heads, in which planar and SPECT images showed scintigraphic findings of N (n = 3, 2), C (n = 1, 3), PH+C (n = 2, 8), RH+C (n = 2, 3), PH (n = 9, 2), and DH (n = 7, 6), respectively. Femoral heads without avascular necrosis demonstrated planar and SPECT findings of N (n = 16, 12), C (n = 0, 6), and DH (n = 3, 1), respectively. When considering C, PH+C, and RH+C as diagnostic findings for avascular necrosis, sensitivities of planar and SPECT images were 21% and 58%, and specificities were 100% and 68%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of rupture of the ascending aorta owing to prosthetic graft dilation following replacement of the descending aorta]

A 55-year-old male was diagnosed as acute type A aortic dissection caused by retrograde propagation from a tear in the descending aorta. A replacement of the descending aorta was performed with a prosthetic graft (VASCUTEK). Sixteen days after the operation, the patient required an emergency operation due to a rupture in the ascending aorta. Transesophageal echo and contrast enhanced CT indicated the point of entry to be at the proximal anastomotic portion of the prosthetic graft and the prosthetic graft (30 mm in diameter) to be dilated to 45 mm. Intimal tear at anastomotic portion owing to graft dilation was suspected as the main factor causing rupture of the ascending aorta.

Growth-inhibitory factor, metallothionein-like protein, and neurodegenerative diseases

Growth-inhibitory factor (GIF), which is deficient in the Alzheimer's disease brain, is a 68-amino-acid metallothionein-like protein. GIF is expressed in the central nervous system but not in peripheral tissues including dorsal root ganglion. GIF is immunocytochemically distributed in Bergmann's glia in the cerebellum and astrocytes in the neocortex, hippocampus, striatum, brain stem, and spinal cord. Strong GIF immunoreactivity is localized in astrocyte cell bodies and fine long processes, which are closely associated with neural perikarya and dendrites, such as layers 2-6 of cerebral gray matter, the molecular layer of the dentate gyrus, the pyramidal layer of the hippocampus and spinal gray matter. GIF is induced in reactive astrocytes in the cerebral cortex in cases of meningitis and Creutzfeldt-Jakob disease or in reactive astrocytes surrounding old cerebral infarcts. On the other hand, GIF is reduced in the subset of reactive astrocytes in lesioned areas of degenerative diseases such as Alzheimer's disease, multiple-system atrophy, Parkinson's disease, progressive supranuclear palsy and amyotrophic lateral sclerosis. Reduction of GIF is correlated with neuronal loss. Thus, perturbation in normal neuroglial interaction in degenerative diseases may lead to a reduction of GIF in reactive astrocytes.

The effects of dobutamine, propranolol and nitroglycerin on an experimental canine model of congestive heart failure

A new experimental model of acute congestive heart failure was established in open-chest dogs, and it was employed to examine the effects of dobutamine, propranolol and nitroglycerin. The model was induced by intracoronary administration of saponin, volume loading and intravenous infusion of methoxamine. Left ventricular end-diastolic pressure (LVEDP) increased from 7.9 +/- 0.6 to 24.2 +/- 1.4 mmHg, and aortic blood flow (AoF) decreased from 0.89 +/- 0.06 to 0.53 +/- 0.04 l/min. Systemic vascular resistance (SVR) increased from 9618 +/- 585 to 16492 +/- 1213 dynes.sec/cm5 and right atrial pressure (RAP) increased from 2.5 +/- 0.2 to 4.2 +/- 0.4 mmHg. Furthermore, Vmax decreased from 71.6 +/- 5.1 to 45.8 +/- 2.9 1/sec, and the time constant of left ventricular pressure decay (T) increased from 40.0 +/- 2.6 to 90.2 +/- 7.9 msec. These hemodynamic changes were stable for up to 80 min. Dobutamine improved cardiac function by increasing Vmax and by decreasing T. Consequently, dobutamine increased AoF and decreased LVEDP, while there was no change in SVR. Nitroglycerin reduced LVEDP, SVR and T; increased AoF; and did not change Vmax. Propranolol produced no improvement in the hemodynamics or cardiac function. These results indicate that the present congestive heart failure model is characterized by global left ventricular dysfunction with lowered cardiac output and increased peripheral vascular tone, and it is beneficial for evaluating the pharmacological properties of drugs for acute congestive heart failure.

Elevation of ceruloplasmin activity involved in changes of hepatic metal concentration in primary biliary cirrhosis

Primary biliary cirrhosis (PBC) patients showed increased ceruloplasmin activity and Cu content in the serum as compared to the control group. Moreover, Cu, Fe, and Zn contents were measured in the livers of autopsied cases. The PBC patients showed increased Cu content and reduced Fe and Zn levels. In PBC cases, Cu transportation via bile is disturbed due to collapse of the interlobular bile ducts and consequently Cu accumulates in the liver. Thus, it is likely that serum ceruloplasmin activity increases to metabolize the accumulated hepatic Cu and that Cu content increases in the serum as a ceruloplasmin-bound form. Furthermore, reduction of Fe and Zn contents in the liver of the PBC patients indicated the possible relationship of ceruloplasmin to Fe and Zn metabolism as well as Cu metabolism.

Sterol composition in polyene antibiotic-sensitive and resistant strains of Malassezia pachydermatis

The membrane sterol compositions of ten strains of Malassezia pachydermatis were analysed by gas-liquid chromatography. Six of these were wild-type strains from clinical sources that were sensitive to polyene antibiotics, whereas the other four strains were resistant mutants that had arisen after treatment with N-methyl-N'-nitrosoguanidine or UV radiation. The wild-type strains contained 838.8 to 1291.7 micrograms of sterol per gram of freeze-dried mycelium. The sterols were composed of 79% ergosterol, 19% fecosterol and 2% lichesterol. The mutant strains contained 277.1 to 348.8 micrograms/g of sterols composed of 76% ergosterol and 24% fecosterol.

[Clinical usefulness of serum assay of EIA-CYFRA 21-1 in lung cancer]

Enzyme immunoassay CYFRA 21-1, a novel lung tumor marker presented in serum (upper limit of normal values: 3.5 ng/ml) was measured in 84 patients with lung cancer and 141 patients with benign respiratory diseases. The positive rate for CYFRA 21-1 in primary lung cancer was 70.3% and the false positive rate in respiratory diseases was 24.1%. In respect to the histological types of lung cancer, CYFRA 21-1 was elevated in 85.0% of squamous cell carcinoma and in 64.8% of other cell types of primary lung cancer. Elevated CYFRA 21-1 levels were found in 40% of Stage I-II, in 80.0% of Stage IIIA-B, and in 73.5% of Stage IV. The overall diagnostic efficiency was 53.4% for CYFRA 21-1 and 44.5% for CEA, respectively. Receiver operating characteristic (ROC) curve analysis suggested that CYFRA 21-1 test has an advantage over CEA. From the results of this study, CYFRA 21-1 was more efficient than CEA as primary diagnostic marker in lung cancer.

Virulence of Rhodococcus equi isolates from patients with and without AIDS

Rhodococcus equi is an emerging opportunistic pathogen of human immunodeficiency virus-infected patients. Thirty-nine isolates of R. equi from immunocompromised patients with and without AIDS were analyzed for the presence of virulence plasmid DNA, expression of 15- to 17-kDa antigens, and their pathogenicities in mice. Of the human isolates, eight contained an 85-kb virulence plasmid, expressed 15- to 17-kDa antigens, and were virulent in mice. Nineteen isolates carried cryptic plasmids of various sizes, and the remaining 12 isolates did not contain any plasmids. These 31 isolates did not express virulence-associated antigens and were not virulent in mice. The results suggested that opportunistic infections in immunocompromised patients could be caused by both virulent and avirulent R. equi strains and that the pathogenesis of R. equi infection in immunocompromised patients appears to be different from that which occurs in foals.

Lower incidence of K-ras codon 12 mutation in flat colorectal adenomas than in polypoid adenomas

In order to clarify genetic changes in flat adenomas, K-ras codon 12 point mutations were examined in 56 flat adenomas, 81 polypoid adenomas and 42 cancers of colon and rectum. The mutation frequency in flat adenomas was 23% (13/56), significantly lower than that in polypoid adenomas (67%: 54/81) and cancers (76%: 32/42). Even mildly dysplastic adenomas or small (less than 5 mm) adenomas showed higher mutation incidence in polypoid type (62%, 57%) than in flat type (23%, 19%). Among flat adenomas, flat elevated lesions exhibited relatively higher mutation frequency than completely flat or depressed ones. As for cancers, 14 tumors (33%) contained mutations only in a minor tumor cell population, indicating that these mutations occur at a late stage of tumorigenesis. These results suggest that the adenoma-carcinoma sequence through flat adenomas may be different from that through polypoid adenomas, and genetic changes may be heterogeneous in colorectal carcinogenesis.

Possible involvement of L-arginine-nitric oxide pathway in modulating regional blood flow to brown adipose tissue of rats

To evaluate whether the L-arginine-nitric oxide (NO) pathway is involved in the regulation of regional blood flow to brown adipose tissue (BAT), the effects of two specific NO synthase inhibitors, NG-nitro-L-arginine methyl ester (L-NAME) and NG-monomethyl-L-arginine (L-NMMA), on the blood flow to interscapular brown adipose tissue (IBAT) were studied in urethane-anesthetized rats. Regional blood flow in IBAT was measured with laser-Doppler flowmetry. An intravenous injection of L-NAME and L-NMMA, but not of either D-enantiomer, caused a transient and dose-dependent increase in IBAT blood flow. Dose-response curves for these NO synthase inhibitors showed that L-NAME was more potent than L-NMMA in increasing IBAT blood flow. We also observed a concomitant pressor effect accompanied by a slight decrease in heart rate following intravenous injection of L-NAME and L-NMMA. An elevation of IBAT blood flow and blood pressure induced by both L-NAME and L-NMMA was reversed by L-arginine in an enantiomerically specific manner. The increase in IBAT blood flow induced by NO synthase inhibitors was of shorter duration and less sensitive to L-arginine than the increase in blood pressure. Our results show that the IBAT blood flow is increased by inhibition of NO synthase and that the response of IBAT vasculature to NO synthase inhibitors is different from that of the resistance vessels which regulate blood pressure. The involvement of L-arginine-NO pathways in modulating microcirculation in IBAT is suggested.

Naloxone attenuates drinking behavior in psychiatric patients displaying self-induced water intoxication

1. The present study was performed to examine the effect of naloxone on drinking behavior in three schizophrenic inpatients with psychosis, intermittent hyponatremia, and polydipsia. 2. Their body weight were checked five times daily and the maximum weight gain during a day was chosen as an index of their polydipsia. 3. After control recording for six weeks, a daily naloxone (0.6 mg) injection series was performed once every two weeks for three series (six weeks). Withdrawal of this drug for six weeks resulted in weight gain recovering to control level. 4. The present study showed that naloxone seems to be a potential treatment for psychiatric patients displaying self-induced water intoxication and that endogenous opioid systems are involved in the compulsive drinking behavior of this syndrome.

Exposure of workers to a mixture of toluene and xylenes. II. Effects

The health effects of exposure to a mixture of toluene and xylene isomers was studied on the fourth or fifth days of a working week in factories in China. The study population comprised 233 subjects (122 men and 111 women), who were exposed to the time weighted geometric mean (maximum) concentrations of toluene (3 (203) ppm) and xylenes (4 (103) ppm). For comparison, 241 non-exposed controls (116 men and 125 women) were recruited from the same regions. The prevalence of some subjective symptoms significantly increased in the exposed population, and the symptom profiles were similar to those found after exposure to toluene or xylenes alone. Haematology and serum biochemistry did not show notable changes. It seems reasonable to conclude that the effects of the toxicities of toluene and xylenes in combination are additive.

Exposure of workers to a mixture of toluene and xylenes. I. Metabolism

The urinary excretion of hippuric acid and methylhippuric acid was studied in workers (233 subjects; 122 men and 111 women) exposed to toluene and xylenes in combination and in non-exposed controls (281 subjects; 141 men and 140 women) recruited from the same factories or factories of the same regions. Smoking and drinking habits of the subjects were obtained by medical interviews. From each worker, one urine sample was collected at the end of a shift and analysed for hippuric and methylhippuric acids by high performance liquid chromatography. Air samples for the estimation of toluene and xylenes were collected with diffusive personal samplers. There was a linear correlation between the time weighted average exposure either to toluene or xylene isomers and the concentrations of hippuric acid or methylhippuric acid isomers in urine. Essentially no difference was found in the correlation between quantitative exposure and excretion in the three xylene isomers. Comparison of the slopes of regression lines indicated the absence of metabolic interaction between toluene and xylenes at the measured concentrations. The metabolism of toluene and xylenes was significantly reduced among smokers or drinkers compared with non-smokers and non-drinkers.

Prenatal diagnosis of peroxisomal disorders. Biochemical and immunocytochemical studies on peroxisomes in human amniocytes

Prenatal diagnoses of peroxisomal disorders, including peroxisome-deficient Zellweger syndrome, isolated deficiency of peroxisomal beta-oxidation enzyme and rhizomelic type chondrodysplasia punctata were investigated by means of the lignoceric acid oxidation assay, indirect immunofluorescence staining and pulse-chase experiments, using cultured amniocytes. Assessment of peroxisomal beta-oxidation activity by means of [1-14C]lignoceric acid oxidation is essential for the diagnosis of a single enzyme deficiency of peroxisomal beta-oxidation with detectable enzyme protein. For the diagnosis of Zellweger syndrome, the absence of peroxisomes was readily determined by immunofluorescence staining of only a few amniocytes. Evidence for abnormal processing of 3-ketoacyl-CoA thiolase leads to the diagnosis of rhizomelic chondrodysplasia punctata. All the fetuses were considered to be normal and the neonates were normal. Use of these methods requires only a small number of amniocytes and will facilitate the prenatal diagnosis of peroxisomal disorders.

[A case of round atelectasis related to spontaneous pneumothorax in a patient with neurilemmomatosis]

A 60-year-old man was admitted to our department for investigation of abnormal shadows on his chest X-ray. He had been diagnosed as having neurilemmomatosis in 1987. His chest X-ray showed nodular shadows in left S5 and S8 and localized spontaneous pneumothorax in left lung field. The nodular shadows, which were in contact with thickening of the pleura, showed curved shadows of bronchi and vessels (so-called comet tail sign). We suspected that they were round atelectasis, but to confirm the diagnosis and to treat the pneumothorax, limited resection of the lung and resection of the bulla were performed. The diagnosis of round atelectasis was confirmed by histological findings. Round atelectasis related to spontaneous pneumothorax is a very rare condition; however, we consider this to be an important case for understanding the pathogenesis of round atelectasis.

[Antigen-induced dynamic alterations of endothelin receptors--guinea pig lung tissues]

Endothelins (ETs) are a family of peptides with potent constrictive activity in vascular and treacheal smooth muscle. The lung tissues are abundant in these peptides and their receptors; the peptides are produced by endothelial cells and airway epithelial cells, while its receptor is mainly located on smooth muscle. Therefore, it has been proposed that endothelins act in a paracrine fashion on nearby smooth muscle, thus regulating its tone. However, little is known about its physiological and pathological roles in pulmonary functions. We hypothesized that ET plays an important role in bronchoconstriction elicited by antigen challenge. In order to test this hypothesis, we investigated tracheal contractile activities and ET-receptors by employing an animal model in guinea pigs. Here, we report that guinea pigs who were sensitized followed by multiple challenges with the antigens had alterations of ET receptor(s) with respect to number and affinity.