Descriptive analysis of the prevalence and the molecular epidemiology of Mycobacterium avium complex-infected pigs that were slaughtered on the main island of Okinawa.

Recent genetic studies have revealed that several epidemiological factors affect Mycobacterium avium complex (MAC) infection in pig populations. However, mechanisms underlying the spread of MAC infection among hog farms have not been clarified. In consideration of this situation, we cross-sectionally investigated the mechanisms underlying the spread of MAC on the island of Okinawa. Pigs slaughtered (n=706,763) and 331 hog farms on Okinawa were surveyed during the years 2002-2004. Two outbreaks of MAC infection were occurred in several farms during survey period. Bacteria were isolated from randomly selected pigs and genotype of isolates was determined by using genetic finger printing methods with the insertion sequence (IS) 1245 restriction fragment length polymorphism (RFLP). Most isolates had large numbers of IS1245 copies, while strains with low copy numbers of IS1245 and isolates without IS1245 were seen in few farms. MACs strains were repeatedly isolated from pigs of the affected farms during the survey period. Those farms with an identical pig rearing systems showed synchronic changes in the prevalence of MAC infection. An industrial farm without an outbreak had an independent pig flow, but maintained distinct MAC strains. Multivariate analysis did not reveal independent factors for the prevalence of the MAC infection. These findings suggest that there were three clusters distinguished genetically in the main island of Okinawa, which were potentially spread by common pig flow. However, the outbreaks occurred because of unspecified conditions on each farm environment.

Inhibition of intracellular hepatitis C virus replication by nelfinavir and synergistic effect with interferon-alpha.

Liver diseases associated with hepatitis C virus (HCV) infection have become the major cause of mortality in patients with human immunodeficiency virus (HIV) infection since the introduction of highly active anti-retroviral therapy. HCV-related liver disease is more severe in HIV-infected patients than in non-HIV-infected patients, but the standard therapies used to treat chronic hepatitis C in HCV/HIV coinfected patients are the same as those for patients infected with HCV alone. HIV protease inhibitors might have potential to down-regulate HCV load of HCV/HIV coinfected patients. In this study, we evaluated the effects of nelfinavir on intracellular HCV replication using the HCV replicon system. We constructed an HCV replicon expressing a neomycin-selectable chimeric firefly luciferase reporter protein. Cytotoxicity and apoptosis induced by nelfinavir were assessed and synergism between nelfinavir and interferon (IFN) was calculated using CalcuSyn analysis. Nelfinavir dose-dependently repressed HCV replication at low concentrations (IC(50), 9.88 micromol/L). Nelfinavir failed to induce cytotoxicity or apoptosis at concentrations that inhibited HCV replication. Clinical concentrations of nelfinavir (5 micromol/L) combined with IFN showed synergistic inhibition of HCV replication in our replicon model. Our results suggest that the direct effects of nelfinavir on the HCV subgenome and its synergism with IFN could improve clinical responses to IFN therapy in HCV/HIV coinfected patients.

Enhancement of biofilm formation onto surface-modified hollow-fiber membranes and its application to a membrane-aerated biofilm reactor.

Surface-modified hollow-fiber membranes were prepared by radiation-induced grafting of an epoxy-group-containing monomer, glycidylmethacrylate (GMA), onto a polyethylene-based fiber (PE-fiber). The epoxy ring of GMA was opened by introduction of diethylamine (DEA). The bacterial adhesivity to this material (DEA-fiber) was tested by immersion into a nitrifying bacterial suspension. The initial adhesion rates and the amount of attached bacteria of the DEA-fiber were 6-10-fold and 3-fold greater than those of the PE fiber, respectively. A membrane-aerated biofilm reactor (MABR) composed of DEA fibers was developed for partial nitrification with nitrite accumulation. Prior to the nitrification test, it was confirmed that the oxygen supply rate (OSR) was proportional to air pressure up to 100 kPa, allowing easy control of oxygen supply. Stable nitrite accumulation was observed in the partial nitrification test at a fixed oxygen supply throughout the operation period, indicating that oxygen was consumed only by ammonia oxidizers. Furthermore, it was demonstrated that oxygen utilization efficiency (OUE) in the ammonia oxidation process was nearly 100% after 300 h incubation.

Distinct localization and target specificity of galanin-immunoreactive sympathetic preganglionic neurons of a teleost, the filefish Stephanolepis cirrhifer.

Immunoreactivity for galanin was examined in the sympathetic preganglionic neurons in the spinal cord, adrenal glands, sympathetic ganglia, and some sensory ganglia of the filefish Stephanolepis cirrhifer. Galanin-immunoreactive neurons were found only in the rostral part, but not in the caudal part of the central autonomic nucleus (a column of sympathetic preganglionic neurons of teleosts). Many galanin-immunoreactive nerve terminals were found in contact with neurons in the celiac ganglia and the cranial sympathetic ganglia on both sides of the body. Most neurons encircled by galanin-immunoreactive nerve fibers were negative for tyrosine hydroxylase. Galanin-immunoreactive nerve fibers were very sparse in the spinal sympathetic paravertebral ganglia. No galanin-immunoreactive nerve fibers were found in the adrenal glands. No sensory neurons of the trigeminal, vagal, or spinal dorsal root ganglia were positive for galanin-immunoreactivity. These results suggest that galanin-immunoreactive sympathetic preganglionic neurons have distinct segmental localization and might project specifically to a population of non-adrenergic sympathetic postganglionic neurons in the celiac and cranial sympathetic ganglia.

Microvasculature of crotaline snake pit organs: possible function as a heat exchange mechanism.

The infrared sensory membranes of the pit organs of pit vipers have an extremely rich capillary vasculature, which has been noted passim in the literature, but never illustrated or studied in detail. We rendered the pit vasculature visible in various ways, namely, by microinjection of India ink, by a combination of ink and succinate dehydrogenase staining, and by making resin casts for scanning electron microscope study. We also used transmission electron microscopy for identifying the types (arterioles, venules, capillaries) of blood vessels. Then we compared the pit vasculature with that of the retina and the dermis. Good visualization of the vasculature was obtained with both ink and resin injection. Arterioles, venules, and capillaries could be distinguished with all methods used. The monolayer vasculature was denser in the pit membrane than in the retina or skin. Each loop of the network enclosed a small number of infrared receptors so that all receptors were in contact with a capillary on at least one side. The forward-looking areas of the pit had a denser network than side-looking areas. Since infrared rays cause nerve impulses by raising the temperature of individual receptors, the capillary network functions not only as a supplier of energy but also as a cooling mechanism to reduce afterimages. Thus the denser network in the forward-looking areas causes these areas to be more sensitive and have better image resolution than the rest of the membrane.

Intracoronary ST-segment alternans during coronary balloon angioplasty.

ST-segment alternans has been described in experimental coronary artery occlusion and in patients with variant angina. It is also seen during coronary angioplasty. This report describes a patient who on balloon inflation during coronary angioplasty demonstrated ST-segment alternans only on intracoronary electrocardiogram but did not on surface 12 lead electrocardiogram. Hemodynamic pulsus alternans of the aortic pressure tracing was not observed during electrical alternans.

Antiischemic effects of nicorandil during coronary angioplasty in humans.

The present study was undertaken on 10 patients with angina undergoing percutaneous transluminal coronary angioplasty. The angioplasty procedure consisted of two successive 30-second balloon inflations at 5 minute intervals. After the first inflation, nicorandil (0.1 mg/kg) was given intravenously over a 2-minute period. The second inflation was then performed 3 minutes after the completion of drug administration. Myocardial ischemia was measured as the magnitude of ST-segment elevation on the intracoronary electrocardiogram (intracoronary ECG) recorded from the guidewire. Nicorandil significantly reduced the magnitude of ST-segment elevation. Nicorandil did not change the heart rate-blood pressure product, nor the oxygen saturation of the blood sampled from the great cardiac vein, nor the velocity of coronary blood flow in those patients with no evidence of collaterals. These results favor the conclusion that nicorandil prolongs the intrinsic ability of cardiac myocyte to withstand oxygen deprivation. This salutary effect is possibly due to a direct cellular mechanism because nicorandil did not modify the peripheral and coronary hemodynamic parameters that govern myocardial oxygen consumption.

[A case of nonobstructive hypertrophic cardiomyopathy associated with ventricular tachycardia and sick sinus syndrome].

We examined, a 64 year old man with hypertrophic nonobstructive cardiomyopathy (HNCM) accompanied with dizziness. Twenty-four hour ECG monitoring showed sinus bradycardia and sinoatrial block. Electrophysiologic study demonstrated inducible sustained ventricular tachycardia (VT) by continuous rapid high right atrum pacing during which systolic blood pressure fell to 40 mmHg. Induced VT degenerated into ventricular fibrillation in ten seconds. We implanted a DDD pacemaker for sick sinus syndrome (SSS) and administrated 90mg/day of diltiazem for VT. Treadmill exercise test was carried out while the patient was taking diltiazem and no arrhythmia was induced. This case of HNCM is rare in that he presented both sick sinus syndrome and sustained VT.

Intravascular ultrasound imaging in human peripheral and coronary arteries in vivo.

To determine the feasibility of intravascular ultrasound imaging in vivo, a miniaturized high frequency transducer catheter was introduced into human peripheral (n = 10) and coronary (n = 4) arteries. Cross-sectional ultrasound images were obtained from iliofemoral arteries in 10 patients using a 20 MHz transducer catheter (1.2 mm in diameter) and from coronary arteries in 4 patients using a 30 MHz transducer catheter 5 French size (Fr) following successful coronary angioplasty. Ultrasound images obtained from peripheral arteries showed a three-layered appearance (echo-reflective intima, echo-lucent media and echo-reflective adventitia) in the normal arteries. In diseased arteries, the location, amount and extent of atheromatous plaque were clearly documented. The arterial diameters measured by ultrasound closely correlated with the measurements by angiography (r = 0.91) in the peripheral arteries. Coronary angiograms obtained following balloon angioplasty revealed smooth edges at the dilatation sites without significant narrowing in all patients. However, a significant amount of residual atheromatous plaque was clearly observed on the ultrasound images at the previously dilated sites. Coronary dissection, which was identified as an echo-lucent area behind the plaque, was noted in 2 patients. Ultrasound images also revealed the presence of calcium in the plaque which was unrecognized on the angiograms in 3 patients. In addition, direct measurement of the lumen cross-sectional area was possible on the ultrasound images.(ABSTRACT TRUNCATED AT 250 WORDS)

Anticoagulant effect of iohexol vs. ioxaglate during cardiac catheterization.

Contrast agent safety during cardiac catheterization (CC) may relate in part to anti- or procoagulant effect. We studied these effects in 177 patients who underwent standard CC (N=112) or percutaneous transluminal coronary angioplasty (PTCA) (N=65) and received either iohexol (N=111) or ioxaglate (N=66). Patients received either 0 or 2000u heparin for CC or 10,000u for PTCA. The groups were similar in regards to age, sex, amount of contrast used, and procedure time. Partial thromboplastin time (PTT) and activated clotting time (ACT) were both significantly increased (P less than .01) in patients who received 10,000u heparin irrespective of type of contrast agent although larger increases were seen in the iohexol group. With 2000u of heparin, ACT and PTT increased significantly (P less than .01) only in the iohexol group. PTT and ACT actually decreased to similar and significant (P less than .01) degrees after both iohexol and ioxaglate when heparin was not used. We conclude: 1) commonly used measures of anticoagulant (ACT and PTT) show greater prolongation after either 2000 or 10,000u of heparin with iohexol than ioxaglate, 2) ACT and PCT appear to shorten with both iohexol and ioxaglate if no heparin is used. This data would suggest that ioxaglate does not have an anticoagulant advantage over iohexol.

Sudden appearance of coronary thrombus observed by angiography--a case report.

A sudden coronary thrombus formation was documented by chance during cardiac catheterization in a patient with postinfarction angina. The thrombus was successfully treated with intravenous urokinase and heparin infusions, and thereafter, coronary angioplasty was performed without any complication.

Exact mechanisms contributing to instability and refractoriness to therapy in patients with unstable angina: coronary arteriographic evaluation.

Ninety one patients with unstable angina were evaluated by clinical and angiographic study. Of 91 patients, 42 (46%) responded poorly to the intensive medical treatment. Emergency coronary arteriography was then performed on these patients. The important pathoanatomical mechanisms contributing to instability of angina pectoris and/or refractoriness to the intensive medical treatment were observed in 19 of 42 patients (45%). These include: 1) More severe disease with left main lesion; 2) Refractory coronary spasm; 3) Coronary dissection; 4) Rapid progression of atherosclerosis; 5) Ulcerating plaque and 6) Coronary thrombus. Our results presented here suggest that an appropriate knowledge regarding pathophysiology might improve the approach to treatment.

The clinical evaluation of the late potentials in patients with ventricular arrhythmias.

We investigated the recognition of late potentials in patients with and without organic heart diseases and spontaneous ventricular arrhythmias. None of the normal subjects had late potentials and patients with ventricular arrhythmias but no organic heart diseases, also had no late potentials as well as patients with idiopathic ventricular tachycardias. Late potentials in patients with idiopathic cardiomyopathy were noted more frequently in the dilated type than in the hypertrophic type, especially in those with high grades of ventricular arrhythmias. Patients with old myocardial infarctions had a higher rate of late potentials recognition in cases of sudden death or ventricular tachycardias. On the other hand, we observed lower rates in patients during early stage of acute myocardial infarction in spite of the evidence of a higher rate of ventricular electrical instability. There was no association between ejection fractions, wall motion scores and late potentials. However, a higher recognition of late potentials was found in patients with inferior or posterior myocardial infarction and ventricular aneurysm. We concluded that the late potential must be evaluated in each of the different groups of organic heart diseases in order to estimate the clinical value of ventricular arrhythmias.

[Long-term vasodilator therapy of chronic refractory heart failure in patients with dilated cardiomyopathy].

The effect of long-term vasodilator therapy (hydralazine, ecarazine or budralazine + isosorbide dinitrate) were evaluated for 20 patients with chronic congestive heart failure due to dilated cardiomyopathy (DCM) resistant to conventional therapy. There were 16 men and four women whose ages ranged from 30 to 74 years (mean 52 years). Fifteen patients were in NYHA class III, and five in class IV. All patients continued their previous therapeutic regimens during this study. Hemodynamic measurements were performed with a triple lumen flow-directed balloon-tipped catheter for 15 patients to evaluate the effects of vasodilator therapy. In the other five patients, heart rate, blood pressure, chest radiography for heart size (CTR) and M-mode echocardiography were monitored. The hemodynamic responses to the combined vasodilator therapy for 15 patients showed significant decreases in afterload and preload concomitant with an increase in cardiac output. The noninvasive evaluations of combined vasodilator therapy in five patients resulted in significant improvement in heart size and ejection fraction. In all 20 patients, symptoms were significantly improved. Side effects and drug toxicity were uncommon during vasodilator therapy. It is concluded that combined vasodilator treatment is the most ajunctive therapy for the management of severe refractory heart failure due to DCM. In addition, long-term nonparenteral vasodilators can be administered even in an outpatient clinic without hemodynamic monitoring.