Effects of cholinergic and adrenergic agonists on the secretion of fluid and protein by submandibular glands of the guinea-pig and the mouse

Significant differences were observed between the guinea-pig and the mouse in terms of the secretion of fluid, protein and secretory granules from submandibular glands in response to pilocarpine, phenylephrine and isoproterenol. In both the guinea-pig and the mouse, the secretory responses induced by pilocarpine, phenylephrine and isoproterenol were inhibited by pretreatment with 4-DAMP, phentolamine and propranolol, respectively. The results suggest that the submandibular glands of the guinea-pig and the mouse have M3-cholinoreceptors, as well as alpha- and beta-adrenoceptors, and that these receptors play different roles in the secretion of fluid, protein and secretory granules from guinea-pig and mouse submandibular glands.

Erythroid differentiation-inducing activity of protoporphyrin IX and its analogs on human leukemia K562 cell line

Protoporphyrin IX, which had been regarded as ineffective in cell differentiation, induced erythroid differentiation of K562 cell line, and its analogs such as hematoporphyrin IX, mesoporphyrin IX, deuteroporphyrin IX and protoporphyrin IX dimethyl ester were also differentiation inducers. The differentiation induced by these compounds was augmented by a retinoid, as is hemin-induced differentiation.

Mutation of a fungal aspartic proteinase, Mucor pusillus rennin, to decrease thermostability for use as a milk coagulant

Mutagenesis of a fungus Mucor pusillus, a producer of an aspartic proteinase named Mucor pusillus rennin (MPR), was performed to obtain the mutated enzymes with decreased thermostability, which is desirable for practical use of the enzyme as a milk coagulant for cheese manufacturing. A fungal mutant strain which produced the mutant enzyme with distinctly reduced thermostability was isolated. Two different mutant alleles of the mpr gene, one with a single amino acid exchange of Ala101 for Thr and the other of Gly186 for Asp, were cloned out of this mutant strain. The mutated mpr genes were expressed in Saccharomyces cerevisiae under the control of the yeast GAL7 promoter to produce the active enzymes in extracellular medium. Both of the mutations, especially Gly186Asp, were confirmed to cause a marked decrease in thermostability of the enzyme. All mutants possessing exchanges of Gly186 for various amino acids by site-directed mutagenesis showed a decrease in thermostability, indicating involvement of this residue to maintain a conformation of the enzyme. A double mutant having the both exchanges, Ala101Thr and Gly186Asp, in a single molecule showed the lowest thermostability without decrease in the enzymatic activity as well as the relative ratio of clotting to proteolytic activity.

"Lupinosis"-like lesions in mice caused by ustiloxin, produced by Ustilaginoieda virens: a morphological study

A crude toxin, obtained by methanol-extraction of a water extract of false smut balls (INA-KOUJI in Japanese) caused by Ustilaginoidea virens on rice panicles, was injected into mice intraperitoneally. Single injection of 100 or 200 mg/kg body weight of the extract was not lethal but caused acute, occasional necrosis of hepatocytes and renal tubular cells, followed by increased number of mitotic figures with occasional multinuclear giant cells. Erosions and ulceration of the forestomach and atrophy of the thymus were observed a week later. Repeated intraperitoneal injection of the crude toxin at the levels of 12 and 25 mg/kg body weight induced more severe necrosis of the liver and kidneys, with delayed occurrence of mitosis. Forestomach erosion also occurred. Serial injection for 10-12 days of either 3 or 6 mg/kg of the crude extract or 400 micrograms/kg of ustiloxin A, using the purified crystals, caused relatively mild but definite liver and kidney lesions similar to those described above. The lesions in the liver and kidney were quite similar to those observed in lupinosis caused by phomopsin A, a mycotoxin produced by Phomopsis leptostromiformis. Isolation of the toxic substance indicates that the contaminated rice panicles may cause toxicosis of cattle, although no field outbreaks have occurred yet.

[A case of Hangman's fracture associated with vertebral arteriovenous fistula treated with trapping]

A case of a traumatic vertebral arteriovenous fistula associated with a hangman's fracture is reported. A 45-year-old male fell down about 2 meters and struck his parietooccipital region against the ground. Profuse nasal bleeding developed. He was transferred to a local hospital, where his respiration was ataxic and blood pressure was low. After intubation, he was transferred to our emergency department. Cervical x-p revealed fracture of C1, C2 and subluxation of C2 body. Because of uncontrollable nasal bleeding, the bilateral maxillary arteries were embolized with spongel. At this time, right vertebral angiograms demonstrated a vertebral arteriovenous fistula with an pseudoaneurysm located at C2 level. On the 13th hospital day, direct balloon occlusion of the fistula was attempted; this could not be achieved because the subclavian and vertebral arteries were tortuous and the balloon catheter could not be introduced to the level of the fistula in the vertebral artery. The patient was only observed until follow-up angiogram on the 24th hospital day revealed enlargement of the pseudoaneurysm. We performed trapping of both the proximal and distal ends of the involved vertebral artery; from C5 to C1. Postoperative course was uneventful, hangman's fracture was fixed with a Halo vest. Four months after operation, fistula and pseudoaneurysm were not opacified on angiogram. We believe that transvascular techniques are the treatment of choice for vertebral arteriovenous fistulas. However, as the next best thing, we can use trapping for the patient whose vessels are too tortuous to introduce the balloon catheter to the involved vessel.

Spatial attention and two modes of visual consciousness

The relationship between spatial attention and visual consciousness was critically examined in an attempt to show the operation of two simultaneously available modes of visual consciousness (i.e., object consciousness, which concerns the conscious identification of objects, and background consciousness, which deals with conscious monitoring of the background scene). The traditional view seems to pay attention only to object consciousness, which is a product of spatial attention. To substantiate the hypothesis, five topics from varied fields of human experimental psychology were chosen: iconic storage, stabilized retinal image disappearance, stable perception of external space, texture segregation and attention, and spatial frequency sensitivity in a figure-ground reversal figure. The findings of these studies suggest that there may be visual consciousness outside of focal attention and that background consciousness operates as a default mode for global scene analysis and early warning of anomalies. Finally, neural substrata for these two modes of consciousness are suggested.

Factors useful in predicting the response to interferon therapy in chronic hepatitis C

To determine how various factors influence the response to interferon (IFN) therapy, we retrospectively studied 157 consecutive Japanese patients with chronic hepatitis C who received various treatment schedules of IFN. They were divided into two groups on the bases of outcome. One group was comprised of 65 patients who achieved a sustained normalization of serum alanine aminotransferase (ALT) levels for at least 6 months after treatment, while the other group was comprised of 84 patients with persistent elevation of serum ALT levels, despite treatment. Genotyping of hepatitis C virus (HCV) was done by polymerase chain reaction (PCR) with genotype specific primers, analysing the variations in nucleotide sequence within the NS 5 region of the HCV genome, namely genotypes PT, K1, K2a and K2b. We then used a multivariate analysis to determine the factors related to mode of treatment, patient characteristics and HCV genotype in relation to the response to IFN therapy. Of the 16 factors analysed, the HCV genotype (genotype K2a or K2b, P < 0.0008), treatment schedule (intermittent administration following a daily schedule, designated as combined schedule, P > 0.0014) and liver histology just before treatment (chronic persistent hepatitis or mild chronic aggressive hepatitis, P < 0.0324) were the most strongly correlated with a normalizing response to IFN therapy. These results suggest that not only are the IFN treatment schedule and patient profile significant, but the properties of the virus also influences the response. However, as the IFN treatment schedule is the only changeable factor, it should be designed to maximize the benefit of IFN therapy.

[A case of splenial astrocytoma with various neuropsychological symptoms]

A case with splenial astrocytoma that showed various neuropsychological symptoms after disappearance of tumor due to chemo- and radiation therapies. A 40-year-old right-handed truck driver visited the Neurosurgical Clinic with complaints of memory disturbance and loosing his way during truck driving. Under diagnosis of protoplasmic astrocytoma chemotherapy and radiation treatments were carried out. These treatments were satisfactorily effective, but the patient showed marked memory deficits and personality change. He was hospitalized, therefore, into the Neuropsychiatric Clinic 20 months after the above mentioned treatments. Aside personality changes such as lack of inhibition and shameless acts, the patient showed interhemispheric disconnection symptoms (dyslexia in the left visual hemifield), memory deficits, and visual perceptual disturbances. His memory deficits consisted of anterograde and retrograde amnesia and disorientation of time and place, indicating that he had typical amnesic syndrome. In other words he had so-called retrosplenial amnesia. His visual perceptual deficits were impaired performance on many tasks already described as tests of visual perception.

Urinary epidermal growth factor levels in patients with acute renal failure

To investigate the importance of epidermal growth factor (EGF) in patients with renal dysfunction, urinary human EGF (hEGF) levels were determined by radioimmunoassay in 16 patients with acute renal failure (ARF) and in 12 healthy controls. Seven patients with chronic renal failure also were studied. Urinary hEGF levels, corrected for urine creatinine concentrations, were significantly decreased in patients with ARF in the acute phase compared with normal control subjects (0.98 +/- 0.20 v 13.74 +/- 1.18 ng/mg creatinine, P < 0.001), and subsequently increased during the recovery phase (6.10 +/- 0.73 ng/mg creatinine, P < 0.001 v acute phase). A significant positive correlation existed between urinary hEGF levels and creatinine clearance in patients with ARF (r = 0.66, P < 0.001). Serum hEGF levels also were significantly lower in patients with ARF compared with normal control subjects (0.10 +/- 0.01 v 0.30 +/- 0.03 ng/mL, P < 0.001). No significant correlation was found between hEGF concentrations in serum and urine. In conclusion, measurement of urinary hEGF may be useful in the diagnosis of ARF and for following the recovery of the kidney after severe tubular injury.

Characterization of the insulin A-chain major immunogenic determinant presented by MHC class II I-Ad molecules

Data are presented which demonstrate the minimal insulin peptide required to activate a large group of insulin-specific T hybrids following presentation by either live or fixed APC, is the N-terminal insulin-A(1-13) peptide. Functional activation and competition assays using both live and fixed APC with 19 synthesized variants of the N-terminal bovine insulin A-chain molecule permitted classification of peptide residues into MHC agretope and T cell epitope regions. Our findings indicate insulin A-chain peptide occupies the Ag binding groove of class II MHC in an extended conformation as a result of intracellular reduction of A-loop disulfide bonds. Insulin A-chain Cys7 and Cys11 residues represent two independent T cell epitopes N- and C-terminal to the A-loop region. Data are presented that demonstrate the unique residues associated with several insulin isoform molecules contribute to the peptide agretope region. Our findings may suggest peptide agretopes may subtly modify the peptide/MHC conformation presented to TCR.

Enhancing effect of cadmium on rat ventral prostate carcinogenesis induced by 3,2'-dimethyl-4-aminobiphenyl

The effects of cadmium given at different stages during 3,2'-dimethyl-4-aminobiphenyl (DMAB)-induced rat prostate carcinogenesis were investigated using male F344 rats. Animals were given 10 subcutaneous injections of 50 mg/kg body weight of DMAB or the corn oil vehicle at two-week intervals. In addition, cadmium was administered at doses of 0, 10, or 30 mumol/kg body weight as single intramuscular injection on the 1st day of the experiment or one day after the last injection of DMAB at week 20. Two further groups were subjected to administration of cadmium at 10 mumol/kg at week 20 and then 5 mumol/kg at week 40, or 10 mumol/kg at week 20 and then 5 mumol/kg at weeks 30, 40 and 50. At the termination, 60 weeks after the beginning of the experiment, the incidences and multiplicity of ventral prostate carcinomas in the groups given cadmium plus DMAB demonstrated a consistent tendency for increase over control values (groups receiving DMAB or cadmium alone). The numbers of carcinomas per rat and per unit area of prostate section were significantly elevated in the two groups given low doses of cadmium after cessation of DMAB administration. Cadmium alone also induced a few prostate carcinomas. The influence on development of prostate tumors did not appear to be a result of the induced severe testicular atrophy because serum testosterone levels were not affected. The results indicate that cadmium and DMAB can act synergistically to cause rat prostate carcinogenesis.

Characterization of the insulin A-chain major immunogenic determinant presented by MHC class II I-Ad molecules

Data are presented which demonstrate the minimal insulin peptide required to activate a large group of insulin-specific T hybrids following presentation by either live or fixed APC, is the N-terminal insulin-A(1-13) peptide. Functional activation and competition assays using both live and fixed APC with 19 synthesized variants of the N-terminal bovine insulin A-chain molecule permitted classification of peptide residues into MHC agretope and T cell epitope regions. Our findings indicate insulin A-chain peptide occupies the Ag binding groove of class II MHC in an extended conformation as a result of intracellular reduction of A-loop disulfide bonds. Insulin A-chain Cys7 and Cys11 residues represent two independent T cell epitopes N- and C-terminal to the A-loop region. Data are presented that demonstrate the unique residues associated with several insulin isoform molecules contribute to the peptide agretope region. Our findings may suggest peptide agretopes may subtly modify the peptide/MHC conformation presented to TCR.

Inactivated products of rifampicin by pathogenic Nocardia spp.: structures of glycosylated and phosphorylated metabolites of rifampicin and 3-formylrifamycin SV

Rifampicin (1) was converted into four inactivated products by pathogenic Nocardia, RIP-1 and RIP-2 by N. brasiliensis and RIP-3 and RIP-4 by N. otitidiscaviarum. MS and NMR analysis showed the compounds to be 3-formyl-23-[O-(beta-D-glucopyranosyl)]rifamycin SV (2), 23-[O-(beta-D-glucopyranosyl)]rifampicin (3), 21-(O-phosphoryl)rifampicin (4) and 3-formyl-21-(O-phosphoryl)-rifamycin SV (5), respectively.

Enhancement by retinoid of hemin-induced differentiation of human leukemia K562 cell line

The effect of retinoid on human leukemia K562 cell differentiation induced by hemin was examined. Retinoids (retinoic acid and synthetic retinoids [Am80 and Ch55]) dose-dependently enhanced hemin-induced erythroid differentiation of K562 cells, though these retinoids themselves did not induce the differentiation. Under optimal conditions, these retinoids caused a doubling of the population of hemin-induced differentiated cells. In addition, co-treatment of cells with hemin and retinoid led to longer maintenance of the differentiated state after the removal of hemin, which might imply acquisition of irreversibility of hemin-induced differentiation. These results suggest that the combination of retinoids with other differentiation inducers might be useful for leukemia therapy in cases where the leukemic cells are poorly responsive or unresponsive to retinoids, alone.

[Traumatic primary brain stem injury and ambient cistern hematoma evaluated with magnetic resonance imaging]

Traumatic hemorrhage in the ambient cistern is thought to be an indirect indication of brain stem injury. In many cases such brain stem lesions cannot be clearly demonstrated by conventional CT scans. Magnetic resonance imaging (MRI) provides a more sophisticated display of the brain stem with improved contrast resolution of structures not appreciated on CT. We present four patients with traumatic ambient cistern hematoma on CT. They showed consciousness disturbance at the initial neurological examination and a Glasgow Coma Scale (GCS) of 7-10. All patients had hemothorax or clavicular fracture ipsilateral to the ambient cistern hematoma that suggested a severe mechanical force from the same direction. Axial, coronal and sagittal MRI scans were obtained with a super-conductive 1.5 T unit (Picker) within 6 days after trauma. Two standard pulse sequences were used; (1) Spin-echo (TR/TE = 500/20) or Inversion Recovery (TR/TI/TE = 3300/600/30) to obtain T1-weighted information and (2) Spin-echo (TR/TE = 2000/100) to obtain T2-weighted information. In case 1 (3-year-old girl) the hematoma which was thought to be located in the ambient cistern on CT was found to be present in the subpial region in the tegmentum on MRI. On T2 weighted image, a high signal intensity area was seen in the perifocal area. This area was demonstrated as a low density area on CT. This patient has remained in a persistent vegetative state 6 months after trauma. In case 3 (31-year-old man) CT demonstrated no abnormal findings in the brain stem. MRI demonstrated a high intensity area in the right cerebral peduncle and left tegmentum.(ABSTRACT TRUNCATED AT 250 WORDS)

The distribution of 3H-labeled endotoxin in the kidney of liver cirrhotic rats

Although the etiology and pathogenesis of progressive renal failure is largely unknown, endotoxin is supposed to be one of the contributory factors. However, the distribution of endotoxin in liver cirrhosis has not been clarified. Therefore we studied the distribution of 3H-labeled endotoxin in the kidney in rats with CCl4-induced liver injury. Daily inhalations of CCl4 on rats for 6 and 10 weeks produced liver fibrosis (LF group, N = 5) and cirrhosis (LC group, N = 5), respectively. At 6 or 10 weeks, animals were sacrificed 24 hours after an intravenous injection of endotoxin labeled with 3H at the galactose moiety (12,000 cpm/1 g body weight). In the liver, 3H-labeled endotoxin was taken up mainly by Kupffer cells as determined by autoradiography. Compared to control rats, in rats of the LC or LF group the measured amount of 3H-labeled endotoxin per gram kidney or ml blood increased, while that of the liver was significantly decreased. A positive correlation of the amount of 3H-labeled endotoxin per weight or volume respectively was shown between kidney and blood, but not between lung or spleen and blood. These results suggest that overflow of endotoxin due to decreased inactivation in the liver causes endotoxemia in liver injury and that the resulting endotoxemia may directly affect the kidney. The resulting endotoxin-induced vasoconstriction may be a contributory factor for the progressive renal failure frequently observed in liver cirrhosis.

Target organ specificity of cell proliferation induced by various carcinogens

The target organ specificities of cell proliferation and histopathological lesion induction by 5 carcinogens having different target organs were evaluated using a multiorgan carcinogenesis bioassay. In Group 1, male F-344 rats aged 6 wk were sequentially treated with N-diethylnitrosamine (DEN, single 100-mg/kg ip injection, week 0), N-methyl-N-nitrosourea (MNU, 4 20-mg/kg ip injections, weeks 0-2), N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN, 0.05% in drinking water, weeks 0-2), N,N'-dimethylhydrazine (DMH, 4 40-mg/kg sc injections, weeks 2-4), and dihydroxy-di-N-propylnitrosamine (DHPN, 0.1% in drinking water, weeks 2-4) during the first 4 wk. In Groups 2-6, rats were treated with only one of the above initiators, applied as in Group 1. Group 7 served as the no-treatment control. Bromouracil deoxyriboside (BUdR) labeling indices (LI) were counted in various organs at weeks 2 and 4. Numbers and areas of glutathione S-transferase placental form positive (GST-P+) liver foci were measured at weeks 2, 4, and 28. Preneoplastic or neoplastic lesion development was assessed at week 28. With regard to specific elevation of cell proliferation in target organs, BUdR LIs in the urinary bladder, liver, and colon were, respectively, increased in the BBN alone, DEN alone, and DMH alone treated groups as well as in Group 1. However, LIs of thyroid, lung, and kidney were also elevated by several carcinogens not including these organs in their carcinogenic target specificity. On the other hand, morphological lesions and GST-P+ foci were limited to Group 1 and the target organs of the corresponding carcinogen-treated groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of the carbohydrate composition of a low-protein meal on the postprandial responses of plasma glucose and insulin in diabetic patients

We determined whether, in 15 diabetic patients, a conventional low-protein diet containing a high proportion of mono- and disaccharides would lead to a deterioration of postprandial glucose metabolism. Three different test meals were given on 3 different days. We found that a high proportion of simple carbohydrates, when consumed as a low-protein meal, aggravated the postprandial hyperglycemia in diabetic patients. The substitution of complex carbohydrates for simple sugars in the meal suppressed postprandial hyperglycemia in diabetic patients.

Cytotoxic activity of spleen-derived T lymphocytes against autologous biliary epithelial cells in autopsy patients with primary biliary cirrhosis

Autoimmunity against biliary epithelial cells is considered to be involved in the pathogenesis of primary biliary cirrhosis (PBC). However, cytotoxic activity of T lymphocytes against biliary epithelial cells has not previously been examined. This study has demonstrated that spleen-derived T lymphocytes were cytotoxic for autologous biliary epithelial cells in all of five patients with PBC, even though it was only detectable at high effector to target ratios. Such cytotoxicity was not found in non-PBC patients. CD8-positive T lymphocytes were shown to be responsible for the cytotoxicity by negative selection, and its inhibition was dependent on the ratio of cold to hot target cells. These observations may support a current hypothesis that the pathogenesis of PBC is partly due to T cell autoimmunity directed against the bile duct epithelium.

A fluorescent probe and a photoaffinity labeling reagent to study the binding site of maytansine and rhizoxin on tubulin

A fluorescent probe (20-demethoxy-20-[3-[[[5-(dimethylamino)naphthalen-1-yl]sulfonyl] amino]propyl]maytansinol 3-isobutyrate, Dan-PDM-3) and a photoaffinity labeling reagent (20-demethoxy-20-[(p-azidobenzoyl)oxy]maytansinol 3-isobutyrate, DABMI) were prepared by derivatization of ansamitocin P-3 (ASMP-3), a maytansinoid. Dan-PDM-3 consists of a tethered dansyl moiety and a maytansinoid moiety. DABMI contains a p-azidobenzoyl group instead of the tethered dansyl moiety of Dan-PDM-3. These compounds were synthesized by reacting 20-demethoxy-20-hydroxymaytansinol-3 isobutyrate (PDM-3) with the corresponding alkyl halide or benzoic acid. Both inhibit tubulin polymerization as potently as ASMP-3 and compete with ASMP-3 for binding to tubulin. The inhibition constants (Ki) of DABMI for the binding to tubulin of rhizoxin and ASMP-3 were 0.54 and 0.36 microM, respectively, which were nearly equal to the dissociation constant (Kd = 0.43 microM) of DABMI measured by the use of [14C]DABMI. The results suggest that Dan-PDM-3 and DABMI interacted with tubulin at the same site as rhizoxin and maytansine. DABMI is irreversibly bound to tubulin upon irradiation. Dan-PDM-3 and DABMI should be useful probes for studying the binding site.

Inactivation of rifampin by Nocardia brasiliensis

Rifampin was glycosylated by a pathogenic species of Nocardia, i.e., Nocardia brasiliensis. The structures of two glycosylated compounds (RIP-1 and RIP-2) isolated from the culture broth of the bacterium were determined to be 3-formyl-23-(O-[beta-D-glucopyranosyl])rifamycin SV and 23-(O-[beta-D-glucopyranosyl])rifampin, respectively. Both compounds lacked antimicrobial activity against other gram-positive bacteria as well as the Nocardia species.

Incomplete interlobar fissures: bronchovascular analysis with CT

Thin-section computed tomographic scans of both lungs in 154 patients, including seven cadavers, with lung cancer (n = 37), diffuse (n = 32) or inflammatory (n = 30) lung disease, other proved or suspected disease (n = 23), or healthy lungs (n = 32) were analyzed to determine the frequency of incomplete interlobar fissure (IIF). An IIF was defined as a discontinuous linear shadow that remained in contact with the chest wall. An IIF was found in 128 of 154 right lungs (83.1%) and 77 of 154 left lungs (50.0%). Some bronchovascular structures crossed or passed through two contiguous lobes in the fused area. The most common bronchovascular structure associated with an IIF was a pulmonary vein; this association was found in 87 right lungs (56.5%) and 20 left lungs (13.0%). An IIF was traversed by a pulmonary artery in only seven right lungs and 13 left lungs or by a bronchus in only three lungs. It is concluded that recognition of an IIF might improve understanding of the spread of pulmonary disease.

Identification of the fragment photoaffinity-labeled with azidodansyl-rhizoxin as Met-363-Lys-379 on beta-tubulin

The rhizoxin (RZX)-binding site on porcine brain tubulin was investigated by photoaffinity labeling with the 5-azido-1-naphthalene sulfonyl (azidodansyl) derivative of RZX, nor-rhizoxin-22-al-5'-azidonaphthalene-1'-sulfonylhydrazo ne (azidodansylrhizoxin: Adan-RZX). Upon ultraviolet irradiation, Adan-RZX generates a highly reactive nitrene, which irreversibly binds to an amino acid residue(s) near the RZX-binding site. The label was found to be on beta-tubulin. Enzymatic digestion of the labeled tubulin generated only one major fluorescent peak on C18 reverse phase HPLC analysis. The labeled site(s) was mapped by using various combinations of highly specific peptidases in succession. That is, the labeled fragment generated by the first peptidase was purified by HPLC and exposed to a second peptidase; if the retention time in HPLC changed after the second digestion, the fragment generated in the first digestion must have contained the recognition site(s) of the second enzyme. From the results of these successive digestions and the known polypeptide sequences, we could identify the labeled fragment as Met-363-Lys-379 of beta-tubulin. This peptidase combination technique should be widely applicable.