Taxonomic evidence that serovar 7 of Erysipelothrix strains isolated from dogs with endocarditis are Erysipelothrix tonsillarum

The levels of relatedness among strains of Erysipelothrix serovar 7 isolated from dogs with endocarditis were estimated by performing DNA-DNA hybridization experiments with the type strains of Erysipelothrix rhusiopathiae and Erysipelothrix tonsillarum. All the canine strains exhibited more than 81% hybridization with the type strain of E. tonsillarum but less than 13% hybridization with the type strain of E. rhusiopathiae. Based on DNA-DNA hybridization results we confirmed that serovar 7 of the isolates from dogs with endocarditis were conclusively identified as E. tonsillarum. These results strongly indicate that some strains of genomic E. tonsillarum are a canine pathogen.

mkp-1 encoding mitogen-activated protein kinase phosphatase 1, a verotoxin 1 responsive gene, detected by differential display reverse transcription-PCR in Caco-2 cells

The major cytotoxic effect of the verotoxins (VTs) produced by strains of VT-producing Escherichia coli is the inhibition of host-cell protein synthesis, but VTs are also suspected to play a role in apoptotic cell signaling and cytokine release. Four differentially expressed genes, including mkp-1 (encoding mitogen-activated protein kinase phospatase 1), were detected by differential display reverse transcription-PCR (DD RT-PCR) stimulated by VT1 in Caco-2 cells. Northern blot analysis showed the induction of mkp-1 mRNA 6 h after VT1 stimulation. Neither mutant VT1 (mutVT1), harboring two mutations in the A subunit (E167Q-R170L), nor cycloheximide induced mkp-1 mRNA, but mkp-1 mRNA was detected with both wild-type VT1 (wtVT1) and anisomycin, a 28S rRNA inhibitor. Therefore, we concluded that the A subunit of VT1 was essential for mkp-1 induction. Increased amounts of phosphorylated c-Jun protein were also found with wtVT1 and anisomycin. Although the precise mechanism of induction of MKP-1 is unknown, we hypothesized that 28S rRNA not only was a sensor for ribotoxic stress, but also was involved in the signal cascade of MKP-1. This is the first report of detection by DD RT-PCR of cellular genes induced by bacterial toxins.

Alterations of thymocyte development, thymic emigrants and peripheral T cell population in rats exposed to 2,3,7, 8-tetrachlorodibenzo-p-dioxin

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exerts diverse biological effects by activating the cytosolic transcription factor, arylhydrocarbon receptor (AhR), which translocates to nuclei by TCDD binding and induces gene expressions. Among the well known-adverse effects of TCDD is thymus atrophy. In thymus atrophy, TCDD alters the proliferation as well as the differentiation of immature thymocytes. Previous studies on the effects of TCDD on thymocyte development were primarily carried out with high doses of TCDD. The present study investigates the effects of lower doses of TCDD (1 or 2 microg TCDD/kg by gavage) on thymocyte development, and furthermore, their sequential consequences on the peripheral T cell repertoire. Seven days after treatment with 1 or 2 microg TCDD/kg, the expression of CYP1A1 mRNA, one of the sensitive responses caused by the binding of TCDD to AhR, was detected in the thymus of rats. Thymus weights and thymus cell numbers decreased in TCDD-treated rats in a dose-dependent manner. The ratios of CD4 single-positive (SP) cells/CD8 SP cells were significantly reduced by TCDD exposure, indicating that the maturation of CD4(+)CD8(+) double-positive (DP) cells was skewed toward CD8 SP cells. These changes in the thymus were parallel to those previously observed with high doses of TCDD exposure. However, the specific reduction of DP cells reported in previous studies with high doses of TCDD was not detected in the present study. On the other hand, the skewing of mature CD4/CD8 T cell ratio in thymocytes by TCDD was not reflected in mesenteric lymph node (LN) lymphocytes, where the proportion of CD8 T cells was rather lowered by TCDD with a significant difference at 1 microg TCDD/kg. In LN lymphocytes, the percentage of recent thymic emigrants (RTEs), defined by the surface markers of Thy1(+)CD45RC(-), was shown to be significantly reduced by exposure to 1 and 2 microg TCDD/kg. T cell supply from the thymus has a crucial role in keeping the diversity of the T cell repertoire. The results of the present study indicated that lower doses of TCDD affect thymocyte development, especially differentiation, and reduce the proportion of RTE in LN, which may cause immunosuppression by reducing the variety of the T cell receptor repertoire.

Extraocular muscle responses to high dose intravenous methylprednisolone in myasthenia gravis

Three patients with generalised myasthenia gravis and three with ocular myasthenia gravis received two to five courses of high dose intravenous methylprednisolone because of the failure of standard immunomodulating therapies. Changes in myasthenic signs were assessed using a four step system for grading muscle weakness and fatiguability in 10 test items. Although a brief and modest amelioration was found from day 1 to day 2 after the initial infusion in two patients with generalised myasthenia gravis, all three experienced a prolonged phase of worsening followed by improvement before the next course. Conversely, for two of the patients with ocular myasthenia gravis, a transient but dramatic improvement of ptosis and ocular immobility was noted from 90 minutes to 5 hours after initiating the first infusion, followed by mild or no exacerbation. This 3 hour improvement may be related not only to possible differences in the neuromuscular junction, but also to corticosteroids unmasking the central adaptation for the peripheral ocular muscle weakness by increasing the acetylcholine release.

Morphology of vulnerable coronary plaque: insights from follow-up of patients examined by intravascular ultrasound before an acute coronary syndrome

OBJECTIVES

To determine the morphologic features of coronary plaques associated with acute coronary syndrome, we prospectively followed patients with atherosclerotic disease identified by intravascular ultrasound (IVUS).

BACKGROUND

Although clinical evaluation of the vulnerable atherosclerotic plaque is important, few data exist regarding the morphology of the vulnerable plaque in clinical settings.

METHODS

We examined 114 coronary sites without significant stenosis by angiography (<50% diameter stenosis) in 106 patients. All the sites exhibited atherosclerotic lesions by IVUS. These lesions consisted of 22 concentric and 92 eccentric plaques with a percent plaque area averaging 59 +/- 12%.

RESULTS

During the follow-up period of 21.8 +/- 6.4 months (range 1 to 24), 12 patients had an acute coronary event at a previously examined coronary site at an average of 4.0 +/- 3.4 months after the initial IVUS study. All the preexisting plaques related to the acute events exhibited an eccentric pattern and the mean percent plaque area was 67 +/- 9%, which was greater than plaque area in the other 90 patients without acute events (57 +/- 12%, p < 0.05). There was no statistically significant difference in lumen area between two patient groups (6.7 +/- 3.0 vs. 7.5 +/- 3.7 mm2). Among 12 coronary sites with an acute occlusion, 10 sites contained the echolucent zones, eight of these shallow and two deep, likely representing a lipid-rich core. In 90 sites without acute events, an echolucent zone in the shallow portion was seen at only four sites (p < 0.05).

CONCLUSIONS

Large eccentric plaque containing an echolucent zone by IVUS can be at increased risk for instability even though the lumen area is preserved at the time of initial study. Compensatory enlargement of vessel wall due to remodeling may contribute to the relatively small degree of stenosis by angiography.

Serovar, pathogenicity and antimicrobial susceptibility of erysipelothrix rhusiopathiae isolates from farmed wild boars (Sus scrofa) affected with septicemic erysipelas in Japan

Six strains of Erysipelothrix rhusiopathiae were isolated from farmed wild boars with acute septicemic erysipelas during the period from 1983 to 1998 in Japan. All isolates belonged to serovar 1a or 2 (predominant serovars in swine). The 50 per cent lethal dose values of those isolates ranged from 10(1.3)to 10(6.2)colony forming units in mice. In swine, all isolates were virulent, capable of inducing localized or generalized urticarial lesions after intradermal inoculation. All of the isolates were resistant to oxytetracycline and/or dihydrostreptomycin. These observations suggest that E. rhusiopathiae strains isolated from wild boars may have aetiological significance in swine erysipelas.

Effects of adjunctive balloon angioplasty after intravascular ultrasound-guided optimal directional coronary atherectomy: the result of Adjunctive Balloon Angioplasty After Coronary Atherectomy Study (ABACAS)

OBJECTIVES

This study was conducted to evaluate: 1) the effect of adjunctive percutaneous transluminal coronary angioplasty (PTCA) after directional coronary atherectomy (DCA) compared with stand-alone DCA, and 2) the outcome of intravascular ultrasound (IVUS)-guided aggressive DCA.

BACKGROUND

It has been shown that optimal angiographic results after coronary interventions are associated with a lower incidence ofrestenosis. Adjunctive PTCA after DCA improves the acute angiographic outcome; however, long-term benefits of adjunctive PTCA have not been established.

METHODS

Out of 225 patients who underwent IVUS-guided DCA, angiographically optimal debulking was achieved in 214 patients, then theywere randomized to either no further treatment or to added PTCA.

RESULTS

Postprocedural quantitative angiographic analysis demonstrated an improved minimum luminal diameter (2.88 +/- 0.48 vs. 2.6 +/- 0.51 mm; p = 0.006) and a less residual stenosis (10.8% vs.15%; p = 0.009) in the adjunctive PTCA group. Quantitative ultrasound analysis showed a larger minimum luminal diameter (3.26 +/- 0.48 vs. 3.04 +/- 0.5 mm; p < 0.001) and lower residual plaque mass in the adjunctive PTCA group (42.6% vs. 45.6%; p < 0.001). Despite the improved acute findings in the adjunctive PTCA group, six-month angiographic and clinical results were not different. The restenosis rate (adjunctive PTCA 23.6%, DCA alone 19.6%; p = ns) and target lesion revascularization rate (20.6% vs. 15.2%; p = ns) did not differ between the groups.

CONCLUSIONS

With IVUS guidance, aggressive DCA can safely achieve optimal angiographic results with low residual plaque mass, and this was associated with a low restenosis rate. Although adjunctive PTCA after optimal DCA improved the acute quantitative coronary angiography and quantitative coronary ultrasonography outcomes, its benefit was not maintained at six months.

Serotyping and pathogenicity of Erysipelothrix strains isolated from tonsils of slaughter pigs in Thailand

Erysipelothrix strains were isolated from the tonsils of 46 (15.0%) of 307 apparently healthy slaughter pigs in Thailand during the period of August to September, 1997. A total of 27 of the 46 Erysipelothrix isolates could be classified into 5 serovars but the remaining 19 were untypable in this study. Of the 25 isolates serologically identified as Erysipelothrix rhusiopathiae, 20, 4, and 1 isolates belonged to serovars 2, 12, and 17, respectively. Only 2 isolates from the tonsils belonged to Erysipelothrix tonsillarum and represented either serovar 7 or 10. Although the periods and the districts of the survey were limited, the information obtained in the present investigation demonstrates the presence of a variety of serovars in pigs in Thailand. Of 29 selected isolates belonging to serovars 2, 7, 10, 12, 17, and untypable, only 5 (17.2%) were virulent for both mice and pigs. Five of these virulent isolates belonging to serovars 2 and 12 killed less than 30% of mice immunized with a swine erysipelas bacterin commercially available in Thailand, suggesting that the vaccine elicited a sufficient immunity to these field isolates.

Learning to design synergetic computers with an extended symmetric diffusion network

This article proposes an extended symmetric diffusion network that is applied to the design of synergetic computers. The state of a synergetic computer is translated to that of order parameters whose dynamics is described by a stochastic differential equation. The order parameter converges to the Boltzmann distribution, under some condition on the drift term, derived by the Fokker-Planck equation. The network can learn the dynamics of the order parameters from a nonlinear potential. This property is necessary to design the coefficient values of the synergetic computer. We propose a searching function for the image processing executed by the synergetic computer. It is shown that the image processing with the searching function is superior to the usual image-associative function of synergetic computation. The proposed network can be related, as a special case, to the discrete-state Boltzmann machine by some transformation. Finally, the extended symmetric diffusion network is applied to the estimation problem of an entire density function, as well as the proposed searching function for the image processing.

Coordination of swallowing and phases of respiration during added respiratory loads in awake subjects

In order to test the hypothesis that different types of respiratory mechanical loads may differently modify the coordination of respiration and swallowing, we investigated the coordination of respiration and swallowing during resistive and elastic loads in 14 healthy subjects. Ventilation was monitored with a pneumotachograph and reflex swallowing was elicited by continuous infusion of distilled water into the pharynx (3 ml/min) and recorded on a submental electromyogram while the subject breathed through a device with a flow-resistive load (180 cm H2O/L/s), an elastic load (70 cm H2O/L), or without any external load. We found that addition of a flow-resistive load did not influence the frequency of swallowing, whereas addition of an elastic load caused a significant increase in swallowing frequency during continuous infusion of water. Analysis of the timing of swallowing in relation to respiratory cycle phase revealed that with flow-resistive loading, swallows occurred preferentially during the inspiratory-expiratory (I-E) transition, whereas with elastic loading, swallows occurred preferentially during the expiratory-inspiratory (E-I) transition. Signs of laryngeal irritation were observed most often during the elastic loading following E-I swallows. These results indicate that different types of respiratory mechanical loads can differently modify this coordination of respiration and swallowing, and suggest that the coordination may be compromised more with elastic loading than with flow-resistive loading.

Expression of cytokine and adhesion molecule mRNA in atherectomy specimens from patients with coronary artery disease

Coronary arteriosclerosis is an underlying condition in acute myocardial infarction (AMI), unstable angina pectoris (UAP) and stable angina pectoris (SAP), and is also related to restenosis (RS) following coronary intervention. To investigate the pathogenesis of this condition, a quantitative reverse transcriptase polymerase chain reaction was used to determine relative levels of mRNA for interleukin (IL)-1beta, IL-6, IL-8, transforming growth factor beta (TGF-beta), intercellular adhesion molecule (ICAM)-1, E-selectin and vascular cell adhesion molecule (VCAM)-1 using directional coronary atherectomy (DCA) specimens. Eleven patients with AMI, 7 with UAP, 10 with SAP and 6 with RS following a previous coronary intervention underwent DCA. The mRNA intensity for each molecule was expressed by comparing it with that of beta-actin mRNA. The AMI and UAP patients showed high frequencies of mRNA for IL-1beta, IL-8, TGF-beta, and ICAM-1 together with strong intensities of expression, whereas SAP patients showed decreased mRNA expression for these molecules. Increased IL-6 mRNA expression was observed only in AMI samples. Specimens from RS patients revealed an accumulated expression of proinflammatory cytokines, except for IL-6, as well as of TGF-beta. The study suggests that variation in mRNA expression may reflect the pathophysiology of specific types of coronary artery disease, and remodeling following vascular injury.

High incidence of glucose intolerance in Vogt-Koyanagi-Harada disease

AIMS

To evaluate glucose tolerance of patients with Vogt-Koyanagi-Harada (VKH) disease before systemic corticosteroid therapy, and to assess changes brought on by treatment.

METHODS

20 VKH patients with acute bilateral panuveitis were studied. 20 healthy adults and 11 Behçet's disease patients with active uveoretinitis served as controls. A 75 g oral glucose tolerance test (OGTT) was given in the acute stage of ocular inflammation before systemic corticosteroid therapy. The OGTT was repeated in the convalescent stage of VKH disease in the patients with glucose intolerance before treatment. Insulin response was examined at the same time as the OGTT when possible.

RESULTS

55% of VKH patients (11/20) showed glucose intolerance but no apparent insulin secretion deficiency was detected. Four of seven patients in the convalescent stage showed improvement of glucose tolerance. None of the normal controls or disease controls showed glucose intolerance.

CONCLUSION

A high incidence of glucose intolerance was found in the acute stage of VKH disease. However, glucose intolerance improved in most cases after systemic corticosteroid therapy. It is possible that glucose intolerance seen in VKH patients may be related to the autoimmune inflammatory process of this disease.

Detection of Mycoplasma in avian live virus vaccines by polymerase chain reaction

The polymerase chain reaction (PCR) was evaluated to detect mycoplasma contamination of avian live virus vaccines. The specificity of the primers showed that 34 strains belonging to nine species of avian mycoplasma DNA could be detected. The sensitivity of PCR to detect mycoplasma DNA was 10(0.2) colony forming units (cfu) of Mycoplasma synoviae and 10(0.7) cfu of Mycoplasma gallisepticum. When M. synoviae and M. gallisepticum were spiked into several avian live virus vaccines, PCR gave a positive reaction except for the avian pox and the avian encephalomyelitis vaccines which were prepared from organ homogenates. Short-term incubation of avian encephalomyelitis vaccines improved the sensitivity of PCR to detect both M. synoviae and M. gallisepticum. Therefore, PCR, combined with the short-term incubation, were shown to be most effective in detecting mycoplasma contamination in all of avian live virus vaccines.

[The skin vasomotor dysfunction of the juvenile muscular atrophy of the distal upper limb--investigation by the ice water immersion test]

We investigated the skin vasomotor function of the juvenile muscular atrophy of the distal upper limb (JMA) by the ice water immersion test. The skin temperature of the bilateral second fingers during ice water immersion were measured in 17 patients with JMA and 25 normal controls. The insufficient fall of the skin temperature during ice water immersion was observed in 5 patients (3 patients in atrophic side, 2 patients in non-atrophic side). The insufficient recovery of the skin temperature was observed in 6 patients (3 patients in atrophic side, 3 patients in non-atrophic side). The both of the insufficient fall and recovery of the skin temperature was observed in one patient (both sides). The insufficient fall of the skin temperature indicates the hypofunction of skin vasomotor activity, and the insufficient recovery of the skin temperature indicates the hyperfunction of skin vasomotor activity because JMA has no disturbance of the peripheral sensory nerve fibers. We conclude that the responsible lesion of these abnormalities may be in the descending sympathetic tract in the cervical spinal cord.

Suppression of actively induced experimental autoimmune uveoretinitis by CD4+ T cells

BACKGROUND

Helper/inducer T cells that exert an inhibitory effect on disease induction have been recently found in many experimental models. In order to clarify the mechanisms of spontaneous remission of experimental autoimmune uveoretinitis (EAU), we investigated the inhibitory effect and the phenotype of the post-recovery suppressor cells.

METHODS

In a series of experiments, we separated spleen cells of rats that had recovered from EAU. Three groups of spleen cells, CD4+ T, CD8+ T and B cells, were each adoptively transferred into naive syngeneic rats before active immunization with retinal soluble antigen (S-Ag) and Freund's complete adjuvant or passive immunization with uveitogenic T cells from donor rats. Inflammation was examined clinically and histologically.

RESULTS

The development of EAU could be significantly prevented by adoptive transfer of CD4+ T cells, whereas CD8+ T cells could not suppress the onset. However, post-recovery CD4+ T cells failed to inhibit EAU induced by passive immunization with uveitogenic T cells.

CONCLUSION

These findings indicate that CD4+ post-recovery (suppressor) T cells may play an important role in the remission of EAU.

Detection of mycoplasma DNA in veterinary live virus vaccines by the polymerase chain reaction

We examined bovine, porcine, canine, feline, avian and mink veterinary live vaccines for the presence of mycoplasma DNA by the polymerase chain reaction including nested-pair primers. Mycoplasma DNA was detected in 22 of the 61 commercial veterinary vaccines (36.1%), although these vaccines did not contain any viable mycoplasma cells.

Serovars of Erysipelothrix strains isolated from pigs affected with erysipelas in Japan

Serovars of 1,046 Erysipelothrix strains isolated from diseased pigs during a period from 1983 to 1993 in Japan were determined by an agar gel double-diffusion precipitation system using typing sera representing all the known serovars, 1 through 23 and type N, of 2 species of Erysipelothrix. A total of 943 strains could be serotyped within the serovars. The remaining 103 strains could not be determined for their serovars and were classified as untypable. Of the 938 (99.5%) strains serologically identified as Erysipelothrix rhusiopathiae, 423 (40.4%) belonged to serovar 1a, 359 (34.3%) to serovar 2, 65 (6.2%) to serovar 1b, 35 (3.3%) to serovar 6, 19 (1.8%) to serovar 5, 11 (1.1%) to serovar 21, and the remaining 26 to serovars 4, 8, 11, 12, 15, 17, or 19. Only 5 (0.5%) strains isolated from the cases of erysipelas belonged to Erysipelothrix tonsillarum and represented serovars 7 or 23.

Amyloid associated muscle pseudohypertrophy: amelioration of motor dysfunction with plasmapheresis and dimethylsulphoxide

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A successful surgical treatment of coronary perforation associated with directional coronary atherectomy--a case report

We encountered a patient with coronary perforation showing cardiac tamponade and shock that occurred during debulking by directional coronary atherectomy. We successfully performed emergent pericardial drainage and aorto-coronary bypass procedures. Bypass surgery is recommended to avoid perioperative myocardial infarction in cases such as ours since the native coronary artery may be at risk of being occluded or narrowed due to oppression by the hematoma and destroyed intima.

Malignant hypercalcemia due to gastric endocrine cell carcinoma

A 62-year-old man was admitted to our Neurology Unit due to consciousness disturbance. Laboratory data showed marked hypercalcemia and azotemia. Serum parathyroid hormone-related protein (PTHrP) level was extremely high. We performed intensive hemodialysis for renal failure, but his condition deteriorated rapidly. On day 10, he died of multiple organ failure. The autopsy revealed gastric undifferentiated adenocarcinoma with systemic dissemination. Immunohistological study showed positive PTHrP staining in carcinoid-like parts of the tumor. This is the first reported case of malignant hypercalcemia due to PTHrP-producing carcinoid or endocrine cell carcinoma of the stomach.