Cell-surface hydrophobicity and scum formation of Rhodococcus rhodochrous strains with different colonial morphologies

Rhodococcus rhodochrous has been reported to be one of the micro-organisms responsible for the formation of scum which is thick and viscous biological foam in activated sludge plants. The hydrophobicity of mycolic acids present on the cell surface and the long-branched shape of the hyphae have been thought to contribute to the scum formation. Cell surface hydrophobicity and scum formation of four R. rhodochrous strains with different colony morphologies were determined, and the results showed that the two rough strains had strong cell surface hydrophobicity and produced scum, whereas the weakly hydrophobic smooth strain and the hydrophilic mucoidal strain did not. All four strains displayed long, branched hyphae, and their electrophoretic mobilities were similar, between pH 4 and 9. These data suggest that changes in the cell surface hydrophobicity of the R. rhodochrous result in changes in the culture characteristics and the formation of scum.

[Acute eosinophilic pneumonia induced by cigarette smoke]

An 18-year-old man was admitted to our hospital because of a dry cough and high fever of acute onset. A chest radiograph revealed diffuse bilateral infiltrates, mainly in peripheral lung zones. Laboratory data showed hypoxemia and leukocytosis, and no eosinophilia. The diagnosis was acute eosinophilic pneumonia, and was based on examination of a transbronchial lung biopsy specimen and on the clinical course. The patient was treated with a corticosteroid and responded quickly. We suspected that the disease was related to smoking because the patient had started smoking two days before the onset of the symptoms. Therefore, a challenge test was done in which the patient smoked cigarettes. By 15 hours after the challenge, he had become severely hypoxemic and by 21 hours after the challenge his pulmonary function had decreased. In this patient, smoking cigarettes appeared to have induced acute eosinophilic pneumonia.

Purification and characterization of a thermostable pyruvate kinase from the actinomycete Microbispora thermodiastatica

The pyruvate kinase of Microbispora thermodiastatica was purified to homogeneity and some properties of the enzyme were characterized. The molecular weight of the enzyme by gel filtration is 277,000. The subunit molecular weight is 55,000 by SDS-polyacrylamide gel electrophoresis, and only one N-terminal amino acid sequence was obtained. It had a pH optimum around pH 4.5 to 7.0 and was stable over the range of pH 4.0-8.0. The enzyme is thermostable and no activity was lost after heat treatment at 55 degrees C for 60 min. AMP activated this enzyme and the saturation curve of the enzyme for PEP changed from sigmoidal type to hyperbolic type in the presence of AMP.

Abnormalities of cortical inhibitory neurons in amyotrophic lateral sclerosis

We have used peristimulus time histograms to study how paired, transcranial magnetic stimulation alters the firing of single motor units and the magnitude of unitary excitatory postsynaptic potentials (EPSPs) recorded from the extensor digitorum communis muscle. With stimulus intensity at threshold and an interstimulus interval of 30 ms, normal subjects (n = 20) demonstrated marked inhibition with a mean test/conditioning EPSP ratio of 13.8% (range 0-51%) and in 7 subjects the ratio was 0 (100% inhibition). In amyotrophic lateral sclerosis (ALS) the ratio was 133% (range 64-267%), P < 0.001. Fifty percent of patients had a test/conditioning EPSP ratio greater than 100% (0 inhibition). The abnormalities were independent of disease severity, bulbar versus spinal ALS, more prominent upper versus lower motor neuron findings, and disease duration. Normal inhibition occurred in 3 individuals, 1 each with multiple sclerosis, Kennedy's syndrome, and monomelic amyotrophy. We speculate that the marked loss of inhibition seen in all patients with ALS, which may be unique to this disorder, reflects loss of inhibitory modulation of the corticomotoneuron and could result in their chronic excitatory drive and eventual demise.

ICAM-1 expression on cardiac myocytes and aortic endothelial cells via their specific endothelin receptor subtype

Endothelin-1 (ET-1) and Endothelin-3 (ET-3) increased the expression of intercellular adhesion molecule-1 (ICAM-1) on rat neonatal cultured cardiac myocytes and rat aortic endothelial cells. ET-1-induced ICAM-1 expression on cardiac myocytes was inhibited by a selective ETA receptor antagonist, S-0139, but not by a selective ETB receptor antagonist, BQ788. ET-3-induced ICAM-1 expression on endothelial cells was inhibited by BQ788 but not by S-0139. Protein kinase C (PKC) inhibitor staurosporine inhibited ETs-induced ICAM-1 expression on both cell types. Treatment of the cells with ETs increased neutrophil adhesion, which was inhibited by S-0139 and staurosporine on cardiac myocytes and by BQ788 and staurosporine on endothelial cells. These results suggest that ETs induce neutrophil adhesion to cardiac myocytes and aortic endothelial cells by increasing ICAM-1 expression, which mediate via ETA receptor on cardiac myocytes and via ETB receptor on aortic endothelial cells. ICAM-1 expression induced by activation of ETA and ETB receptors appears to be mediated through the PKC pathway.

8-Hydroxydeoxyguanosine in human leukocyte DNA and daily health practice factors: effects of individual alcohol sensitivity

A typical oxidative DNA damage, 8-hydroxydeoxyguanosine (8-OHdG), was evaluated in human polymorphonuclear leukocytes (PMN) and mononuclear leukocytes (MN) by an anaerobic determination method. The mean 8-OHdG values were the lowest level ever reported [PMN, 3.07 +/- 1.45; MN, 2.37 +/- 1.21 8-OHdG/10(6) deoxyguanosine molecules (dG); n = 92]. According to a self-administered questionnaire to 92 healthy male workers, the relationship was investigated between 8-OHdG in leukocytes and daily health practice factors, that is, the frequency of physical exercise, smoking status, alcohol drinking, nutritional balance, and the degree of mental stress. A significant difference was observed only in alcohol drinking in subjects classified by aldehyde-dehydrogenase 2 isozyme (ALDH2) genotype. Habitual alcohol intake appeared to increase 8-OHdG in PMN from ALDH2-deficient subjects. Neither age, body mass index, nor any other factors examined showed any significant correlation with the 8-OHdG levels in leukocytes.

Reduced corticomotoneuronal excitatory postsynaptic potentials (EPSPs) with normal Ia afferent EPSPs in amyotrophic lateral sclerosis

We studied excitatory postsynaptic potentials (EPSPs) arising in single spinal motoneurons (composite EPSPs) induced by Ia afferent and magnetic cortical stimulation in 28 normal subjects ranging in age from 24 to 84 years and 28 patients with amyotrophic lateral sclerosis (ALS) aged 34 to 82 years. The subjects voluntarily recruited single motor units of the first dorsal interosseous muscle. Using peristimulus time histograms, we determined changes in the firing probability of the first dorsal interosseous motor units and measured the magnitude of the EPSP. An early period of increased firing probability (primary peak) occurred at approximately 30 msec after la afferent and 25 msec after cortical stimulation, reflecting underlying EPSPs arising in spinal motoneurons induced by either projection. The latency of the primary peaks for both Ia afferent and cortical stimulation was mildly prolonged in ALS, suggesting a loss of the fastest-conducting spinal motoneurons. Patients with ALS had la afferent-driven EPSPs whose amplitude and rise time were equivalent to those of normal subjects. However, the ratio of cortical to la afferent-driven composite EPSPs in ALS was significantly lower than that for normal subjects. Fourteen of 28 ALS motor units had cortically driven EPSPs that were small or large only because of a prolonged rise time. The findings suggest that in ALS, corticomotoneuronal attrition or dispersion of the descending volley occurs in the presence of normally functioning spinal motoneurons to which they project.

Factors influencing visual acuity after photocoagulation for subfoveal choroidal neovascularization of exudative age-related macular degeneration

PURPOSE

To evaluate factors influencing visual acuity after laser photocoagulation for subfoveal choroidal neovascularization of exudative age-related macular degeneration.

METHODS

Subfoveal choroidal neovascular membranes were photocoagulated. Factors favoring a visual acuity of 20/200 or better were analyzed using Fisher's exact probability test or chi-square test on 28 eyes in which visual acuity was 20/200 or better, and 23 eyes with a visual acuity below 20/200 at the most recent follow-up examination.

RESULTS

Factors predicting a postoperative visual acuity of 20/200 or better were (1) distance between one lateral margin of the neovascular membrane and the center of the foveal avascular zone was one-third disc diameter or less, and (2) pretreatment retinal sensitivity at the fixation point was 10 dB or more.

CONCLUSION

Good indications for photocoagulation treatment of subfoveal choroidal neovascular membrane were a neovascular membrane margin near the center of the foveal avascular zone and relatively good retinal sensitivity at the fixation point adjacent to the scotoma. These factors predict a visual acuity of 20/200 or better after treatment.

Elevation of serum levels of matrix metalloproteinase-2 and -3 as new predictors of recurrence in patients with urothelial carcinoma

BACKGROUND

The relationship between serum levels of matrix metalloproteinase-2 (MMP-2) and MMP-3 and recurrence in patients with urothelial carcinoma after complete resection was studied to determine whether the enzymes could be a new predictor of recurrence.

METHODS

Serum levels of MMP-2 and MMP-3 in 146 healthy controls, 52 patients with superficial (noninvasive) and 35 patients with advanced (invasive or metastatic) bladder carcinoma, and 30 patients with advanced upper urothelial carcinoma (renal pelvis and ureter) were measured by a one-step sandwich enzyme assay.

RESULTS

Among the 53 patients with advanced urothelial carcinoma who underwent complete resection, the 1- and 3-year disease free survival rates of patients with elevated serum levels of either or both of the enzymes were 51% and 19%, respectively, whereas those of patients with normal serum levels of these enzymes were much higher, 86% and 79%, respectively (P < 0.005). In pT2N0M0 and pT3N0M0 patients who underwent complete resection, the recurrence rate in those with preoperative elevated serum levels of either or both of the enzymes was significantly higher than that in patients with normal levels (75% vs. 8%; P < 0.001). The 1- and 3-year disease free survival rates of pT2N0M0 and pT3N0M0 patients with elevated serum levels of either or both of the enzymes were 55% and 21%, respectively, which was significantly lower than that of patients with normal levels (92%; P < 0.001).

CONCLUSIONS

The results of this study indicate that the elevation of serum levels of either MMP-2 or MMP-3 or both could be new predictors of recurrence in patients with advanced urothelial carcinoma after complete resection.

Pigmentary degeneration induced by N-methyl-N-nitrosourea and the fate of pigment epithelial cells in the rat retina

Pigmentary degeneration of the retina was induced by a single intraperitoneal injection of 75 mg/kg of N-methyl-N-nitrosourea (MNU) in female Brown-Norway colored rats at 50 days of age, which were then observed at 24, 48 and 72 h and 7, 21, 35 and 150 days after the treatment. MNU-treated rats showed selective destruction of the photoreceptor cells by an apoptotic mechanism 24 h after the treatment, and the destruction was completed by day 7. During the photoreceptor cell degeneration, proliferation of Müller cells and infiltration of macrophages was prominent 72 h and 21 days after the treatment, respectively. Müller cell proliferation and macrophage infiltration corresponded to degenerative photoreceptor cell phagocytosis, and proliferating Müller cell processes responded to stabilize the damaged retina. Pigment epithelial cell detachment from the Bruch's membrane was seen 72 h after the treatment, and migration within all layers of the retina was seen at day 7 when photoreceptor cells were lost. At 21, 35 and 150 days after the treatment, lack of photoreceptor cells and deposition of pigment epithelial cells within the retina but not in contact to vascular endothelial cells were characteristic. MNU-induced photoreceptor apoptosis followed by Müller cell and macrophage reaction then pigment epithelial cells deposition within the retina partially resembles retinitis pigmentosa in humans.

Role of human cytochrome P4502A6 in C-oxidation of nicotine

Nicotine is primarily metabolized to cotinine in humans. In this study, human cytochrome P450 (CYP) isoform involved in cotinine formation was identified. The formation of cotinine in 16 human liver microsomes was determined with a 50 microM nicotine concentration and with a cytosol preparation as a source of aldehyde oxidase. Cotinine formation in human liver microsomes significantly correlated with immunochemically determined CYP2A6 levels (r = 0.663, p < 0.05), coumarin 7-hydroxylase activities (r = 0.831, p < 0.01), and cotinine 3'-hydroxylase activities (r = 0.735, p < 0.01) that are responsible for CYP2A6. In inhibition studies, cotinine formation in human liver microsomes was inhibited by coumarin and rabbit anti-rat CYP2A1 antibody specifically. When the capability of microsomes of B-lymphoblastoid cells expressing human CYPs to perform biotransformation of nicotine to cotinine was determined, cDNA-expressed CYP2A6 exhibited the highest cotinine formation. The KMapp values from microsome expressing CYP2A6 cDNA were similar to the value obtained from human liver microsomes. The large interindividual variabilities in cotinine formation and immunochemically determined CYP2A6 levels were observed in human liver microsomes, suggesting genetic polymorphism of CYP2A6. Nicotine is a new in vivo probe for phenotyping of CYP2A6 in humans.

Reconsideration of the sequence of rigor mortis through postmortem changes in adenosine nucleotides and lactic acid in different rat muscles

We examined the changes in adenosine triphosphate (ATP), lactic acid, adenosine diphosphate (ADP) and adenosine monophosphate (AMP) in five different rat muscles after death. Rigor mortis has been thought to occur simultaneously in dead muscles and hence to start in small muscles sooner than in large muscles. In this study we found that the rate of decrease in ATP was significantly different in each muscle. The greatest drop in ATP was observed in the masseter muscle. These findings contradict the conventional theory of rigor mortis. Similarly, the rates of change in ADP and lactic acid, which are thought to be related to the consumption or production of ATP, were different in each muscle. However, the rate of change of AMP was the same in each muscle.

Bond strength to crown and root dentin

PURPOSE

To investigate (1) the tensile bond strengths of four commercial dentin bonding systems to bovine crown and root dentin and (2) the structure of the hybrid layers for each system bonded to the two dentin substrates.

MATERIALS AND METHODS

Superficial surfaces were exposed in bovine crown and root dentin. The teeth were embedded in plaster and a 3 mm diameter bonding area was demarcated. The four bonding systems used were All-Bond 2, Super-Bond D-Liner Plus, Clearfil Liner Bond II, and ProBond. Bonding procedures followed the manufacturers' instructions with the exception of Super-Bond D-Liner Plus where the primer was left in situ for 60 seconds. Tensile bond strengths were tested after 24-hour storage in 37 degrees C deionized water. Specimens were also prepared for SEM observation of the hybrid layer, after treatment with 10% phosphoric acid, and 10% phosphoric acid and 5% sodium hypochlorite.

RESULTS

Statistically lower bond strengths to crown dentin when compared with root dentin were observed for All-Bond 2, whereas Liner Bond II showed the opposite (P < 0.01). Both ProBond and Super-Bond D-Liner Plus showed no statistical differences between crown and root dentin (P > 0.05). Hybrid layers could be observed for All-Bond 2, Liner Bond II and Super-Bond D-Liner Plus, with no apparent differences between the hybrid layers of crown and root dentin. In the case of ProBond, where the smear layer was not removed during the priming stage, it appeared that the primer had infiltrated and caused hybridization of the smear layer. The differences in bond strength were thought to be related to the different bonding mechanisms of each material, as well as possible variations in the crown and root dentin substrates.

Kappa-casein suppresses melanogenesis in cultured pigment cells

The effects of bovine milk proteins on melanogenesis in B16 cells were examined. Both whey protein isolate and casein exhibited depigmenting properties. Among the major protein components of milk--including beta-lactoglobulin, alpha-lactalbumin, alpha-, beta-, and kappa-casein--only kappa-casein exhibited the depigmenting effect. However, the carboxyl terminal peptide of kappa-casein, glycomacropeptide, did not show this activity. Also, kappa-casein promoted the proliferation of the cells and inhibited the activity of tyrosinase in the cells. These results indicate that kappa-casein acts as a melanogenesis-suppressing modulator.

In vivo transfer of gene and oligodeoxynucleotides into skin of fetal rats by incubation in amniotic fluid

One of the tools to test an in vitro hypothesis in vivo is transgenic/gene targeting technology. Transgenic technology provides many advantages such as: (1) the study of specific gene function as systemic and developmental effects; and (2) testing of specific gene function chronically. nevertheless, one disadvantage of this technology is the difficulty in tissue-specific targeting of the transgenic expression. Another useful tool is the in vivo gene transfer approach. Therefore, we tested a potential novel model for the study of transgene expression and knock-out using antisense technology. Here, we have demonstrated that incubation of hemagglutinating virus of Japan (HVJ)-liposome complex containing FITC-labeled oligonucleotides in the amniotic fluid of fetal rats resulted in the nuclear localization of fluorescence in the skin (epidermis and dermis). Similarly, transfection of beta-galactosidase gene resulted in positive staining in several surface layers of the skin. Thus, local gene or antisense oligonucleotide transfer approach into the skin may be useful for studying the role of autocrine/paracrine mediators and treating diseases.

[Summer-type hypersensitivity pneumonitis in a patient with a positive skin test (15 minutes) for Trichosporon mucoides and a high serum IgE level]

The serum IgE level is usually not high in hypersensitivity pneumonitis (HP) because it develops from Type III and Type IV allergies (Gell and Coombs). However, we have previously reported infiltration of lymphocytes and mast cells in patients with summer-type HP and a high serum IgE level. We encountered a 56-year-old woman with summer-type HP who had a high serum IgE level and a positive skin reaction to the causative antigen. She was admitted to our hospital because of coughing, fever, and dyspnea. On admission, a chest X-ray film and a chest CT scan disclosed ground-glass opacity and diffuse small nodular shadows. Her PaO2 was 56 mmHg on room air and her serum IgE level was high (725 U/ml). Pulmonary-function testing revealed a low DLCo, but the FEV1 was normal. Summer-type HP was diagnosed because of a positive test for serum antibody to Trichosporon mucoides (TIMM1573), a positive result on an antigen challenge test, and because pathological examination of specimens obtained by transbronchial lung biopsy showed severe infiltration of lymphocytes. After admission, her serum IgE levels gradually improved along with the symptoms and the PaO2. A skin test for the causative antigen was done to study the early immunological reaction, and a positive result (22 mm x 24 mm) was obtained for T. mucoides (TIMM1573) in only 15 minutes. We could not elicit any history of atopy that may have been associated with the high serum IgE level and the positive skin test. Therefore, we suspect that this patient had an early immunologic reaction (Type I allergy) to T. mucoides, and that Type I allergy is involved in the development of HP.

Clinical significance of Ki-67 staining index in acoustic neurinoma

The correlation between various clinical parameters and MIB-1 (Ki-67) staining indices was evaluated in 58 acoustic neurinomas. The index ranged from 0.37% to 6.61% (mean 1.70%), and did not correlate with age, sex, or initial tumor volume. Sixteen of the 18 tumors removed subtotally or partially showed regrowth, and two showed a volume reduction. The 16 patients with regrowth were divided into two groups according to Ki-67 staining index, < 2.00% and > or = 2.00%. These groups had a significant difference in tumor doubling time (TDT). In addition, there was a significant logarithmic correlation between Ki-67 staining index and TDT. Ki-67 staining index can be used as an index of regrowth rate in partially or subtotally removed acoustic neurinomas. Intraoperative assessment of Ki-67 staining index may be useful for better management planning as well as the estimation of prognosis.

Pheromone-induced stimulation of hypothalamic gonadotropin-releasing hormone pulse generator in ovariectomized, estrogen-primed goats

As an example of pheromone-induced activation of reproductive function, the 'male effect' is well known in seasonally anestrous goats. The effect of this male pheromone on the hypothalamic gonadotropin-releasing hormone (GnRH) pulse generator activity was examined by monitoring the characteristic increases in the multiple-unit activity (MUA volleys) of the medial basal hypothalamus which had been associated with the pulsatile secretion of luteinizing hormone in ovariectomized goats carrying estradiol implants under 16L/8D condition. Male goat hair was used as the source of male pheromones, and the exposure to the hair was accurately timed to be midway between succeeding MUA volleys. The interval from the pheromone exposure to the subsequent volley was measured, so that the primer pheromone effect was assessed in terms of the stimulation of the GnRH pulse generator activity. Exposure to hair from an intact male goat resulted in occurrence of a MUA volley within a few minutes (1.7 +/- 0.2 min, n = 15) with the intervolley interval being apparently shortened as compared with the preexposure period. Hair from castrated male goats, on the other hand, had no such stimulatory effect at all on the hypothalamic GnRH pulse generator activity, but treatment of the castrated goats with testosterone for 2 months resumed the pheromone activity. The present results provide first direct evidence for the central action of the primer pheromone in a mammalian species, and pheromonal stimulation of the reproductive neuroendocrine system is shown to be exerted by instantaneously stimulating the hypothalamic GnRH pulse generator activity.

Pseudoaneurysm of the cystic artery associated with upper gastrointestinal bleeding

Pseudoaneurysm of the cystic artery is a cause of hemobilia, and is extremely rare, with only eight cases having been reported in the world literature. We report a case of pseudoaneurysm of the cystic artery in a 72-year-old Japanese man. The patient experienced epigastric pain and melena, and was found to have jaundice and liver dysfunction. Repeated gastroendoscopy did not reveal the cause of the alimentary tract bleeding; however, color-Doppler ultrasonography detected an aneurysm of the cystic artery in the gallbladder. Selective hepatic arteriography demonstrated that the posterior branch of the cystic artery was markedly dilated and that an aneurysm had formed in the midst of the artery. We diagnosed hemobilia due to the pseudoaneurysm of the cystic artery, and associated gastrointestinal bleeding. Cholecystectomy was performed immediately. Pathologically, the gallbladder showed acute calculous cholecystitis. This case emphasizes the importance of including hemobilia in the differential diagnosis whenever gastrointestinal bleeding is associated with signs of biliary disorder; color-Doppler imaging is a favorable modality for the diagnosis of pseudoaneurysm of the cystic artery.

[Detection of lesions in bone marrow for the diagnosis of miliary tuberculosis: reliability of bone marrow aspiration and biopsy in view of distribution pattern of lesions in autopsy cases]

The usefulness of the serial section method was investigated in four bone marrow aspirates, four biopsies and nine autopsy specimens obtained from patients with miliary tuberculosis who were admitted to our hospital between 1974 and 1994. In original sections, granulomas consistent with tuberculosis were found in two out of four aspirate specimens (50%) but in none of the four bone marrow biopsies. By using serially out sections, however, granulomas were detected in two more aspirate specimens and two biopsies which were negative in original sections. Consequently four of four aspirates (100%) and two of four biopsies ((50%) became positive. In addition, the distribution of granulomas was investigated using vertebral bone marrows obtained from 12 autopsy cases. We divided the vertebral bone marrows obtained from 12 autopsy cases. We divided the vertebra into the peripheral and central portions. Granulomas were more frequently found in the peripheral portions than in the central. The higher detection rate of granulomas in the peripheral bone marrow when the biopsy and aspiration needles easily reach, suggests that bone marrow aspiration and/or biopsy would be a useful procedure for the diagnosis miliary tuberculosis. Therefore if serial sections were utilized for such samples in the miliary tuberculosis patients, the detection rate is expected to became much higher.

Formobactin, a novel free radical scavenging and neuronal cell protecting substance from Nocardia sp

Formobactin, a new free radical scavenger, was isolated from the culture of Nocardia sp. strain ND20. The structure of formobactin was determined to be a member of the nocobactin group antibiotics. Formobactin inhibited lipid peroxidation in rat brain homogenate. Formobactin also showed the activity to suppress L-glutamate toxicity in neuronal hybridoma N18-RE-105 cells.