Repeat angiography and magnetic resonance imaging (MRI) of dissecting aneurysms of the intracranial vertebral artery. Report of four cases

We here present 4 cases with dissecting aneurysm (DA) of the intracranial vertebral artery, who were followed up by repeat cerebral angiography and MRI. The patients consisted of 2 males and 2 females, and the mean age was 43 years. Two cases were associated with polyarteritis nodosa (PN) and hypertension, respectively. Three of the cases developed subarachnoid haemorrhage (SAH), while the other one suffered from lateral medullary syndrome. In cerebral angiography, "pearl and string" signs were revealed in all cases, while a "double lumen" indicating a true diagnostic sign of DA was demonstrated in only one case. Repeat angiography showed that a bleb formation with a bulging of the aneurysmal sac was seen in 2 cases, and an irregularity of the wall in one case. On the other hand in one case, the ectatic part shrank, while the stenotic part was restored. In magnetic resonance imaging (MRI), a hyperintensity mass on T 1-weighted image (T 1-WI) adjacent to flow void suggesting either an intramural haematoma or a linear shape hyperintensity on T 1-WI were demonstrated in 3 cases. In the follow up MRI done in 2 cases, a serial change in the intensity from iso-intensity to hyperintensity on T 1-WI was observed in one case suggesting intramural haemorrhage, while an enlargement of the ectasic flow void was seen in the other case. Three of 4 cases were operated on by trapping of the aneurysms. One, who had systemic vascular diseases due to PN, and repeat angiography showed a regression of the aneurysm, was conservatively treated.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of diabetes on lipid peroxidation and scavenger activity in ischemia/reperfusion injury

This study examined the effects of ischemia/reperfusion on cardiac function and diabetes-associated lipid peroxidation and scavenger induction in isolated working hearts. Cardiac function in diabetic rats was depressed in proportion to the duration of diabetes. Plasma levels of malondialdehyde (MDA) were increased significantly after diabetes of 1-week duration (1wD). MDA levels in the myocardium were increased significantly after 4-weeks (4wD) and tissue superoxide dismutase (SOD) activity was also elevated significantly in 8-week diabetic rats (8wD) as compared to control values. In both controls and diabetics, tissue MDA concentrations increased significantly during the first 3 min of reperfusion following 20 min of ischemia, compared with preischemia levels. At the end of reperfusion, tissue MDA levels decreased in controls and 1wD hearts, but remained elevated in the 4wD and 8wD cases. The SOD activity in 8wD hearts decreased significantly after 20 min of global ischemia followed by 30 min reperfusion, compared with preischemia levels. By contrast, there were no significant differences between preischemic and after-reperfusion data for parameters of cardiac function in 8wD rats. Thus, lipid peroxidation appears to have little influence on cardiac function during ischemia/reperfusion in rats with chronic diabetes.

Effects of prolonged application of isoprenaline on intracellular free magnesium concentration in isolated heart of rat

1. The effect of prolonged application of isoprenaline on intracellular free-Mg2+ concentration ([Mg2+]i) was examined by use of 31P-nuclear magnetic resonance (31P-n.m.r.) in rat isolated hearts. Left ventricular pressure (LVP) was simultaneously measured. 2. [Mg2+]i was estimated from the separation of the alpha- and beta-ATP peaks, using the dissociation constant of MgATP 38 microM (established previously). In normal (phosphate-free, Krebs-Henseleit) solution, [Mg2+]i was approximately 0.4 mM. 3. When isoprenaline was applied for 100 min, a transient increase in [Mg2+]i was observed during the initial 25 min, whilst concentrations of ATP ([ATP]) and phosphocreatine ([PCr]) decreased and [Pi] correspondingly increased. During the subsequent 75 min of isoprenaline application, [Mg2+]i decreased below its resting levels. Washout of isoprenaline restored [Mg2+]i and [PCr], but [ATP] remained low. These changes elicited by isoprenaline were not observed in the presence of propranolol, a typical alpha-adrenoceptor blocker. 4. Isoprenaline increased both LVP and heart rate. The increased LVP and heart rate slowly returned to lower values during prolonged application of isoprenaline, but remained higher than those before application. 5. The transient rise in [Mg2+]i elicited by isoprenaline could be attributed to the decrease in [ATP] resulting in a release of Mg2+. The subsequent decrease in [Mg2+]i during the prolonged applications suggests that beta-adrenoceptor stimulation itself facilitates Mg(2+)-extruding mechanism(s).

MRI of soft-tissue lesions: opposed-phase T2*-weighted gradient-echo images

We evaluated the ability of opposed-phase T2*-weighted gradient-echo (T2*GE) MRI to demarcate soft tissue lesions. The series contained 37 cases, including 18 benign tumors, 8 malignant tumors, and 11 miscellaneous nonneoplastic soft-tissue lesions. Images were obtained on a 0.5 T magnet with T2*GE imaging (TR/TE 300/22 ms, 20 degrees). Results were compared with those of T1-weighted SE images (500/20-40) and T2-weighted SE (T2SE) images (2,000/80). The T2*GE images were similar to T2SE images with respect to the signal behavior and internal architecture of the masses in many cases. In some instances, they were better than T2SE images in delineating the lesions and adjacent fat tissue, in delineating the lesions and adjacent small vessels, and in depicting special features such as hemosiderin deposits. They were inferior to T2SE images in delineating the lesions and adjacent muscles. Because of reduced lesion-muscle delineation, T2*GE images can not be substituted for T2SE images in the evaluation of soft-tissue lesions, but are useful as an adjunct in some cases.

Circadian blood pressure variation in diabetic patients with autonomic neuropathy

OBJECTIVE

To elucidate distinctive patterns of circadian variation of blood pressure in diabetic patients.

DESIGN

Circadian variations and indices of blood pressure variability were examined by non-invasive ambulatory blood pressure monitoring. The indices were assessed for a correlation with various possible signs of autonomic neuropathy, including the coefficient of variation of the RR interval and orthostatic hypotension.

METHODS

The study was conducted on 38 normotensive diabetics and 15 age- and sex-matched non-diabetic controls, all of whom were outpatients at the Third Department of Internal Medicine in Nagoya University Hospital. Ambulatory blood pressure measurements were taken in all subjects and the coefficients of variation in the RR interval and postural changes in blood pressure were determined.

RESULTS

The diabetic patients demonstrated a different pattern of circadian variation in blood pressure from that of the non-diabetics. Diurnal-nocturnal differences were significantly smaller in diabetics than in non-diabetic controls. Statistically significant correlations were found between diurnal-nocturnal differences in blood pressure and the duration of diabetes, glycaemic control, the coefficient of variation in the RR interval and the change in blood pressure on standing. A subgroup of diabetic patients with severe autonomic neuropathy showed the lowest diurnal-nocturnal differences.

CONCLUSIONS

In diabetic patients with autonomic neuropathy circadian variations in blood pressure are blunted. Ambulatory blood pressure monitoring can detect these abnormal variations and therefore may be useful in evaluating diabetic autonomic neuropathy.

Are diabetic hearts more resistant to ischemia/reperfusion injury?

The present study was designed to investigate the cardiac impairment during ischemia/reperfusion injury in rats with streptozotocin-induced diabetes vs controls. Male rats were divided into three groups: controls, one-week diabetic rats (1wDM) and four-week diabetic rats (4wDM). In the isolated working heart, left ventricular developed pressure (LVDP), left ventricular end-diastolic pressure (LVEDP), and maximum positive and negative dP/dt were measured before ischemia and after 20 min of global ischemia followed by 30 min reperfusion. In the pre-ischemic state, hearts of 4wDM showed a significant (p < 0.05) depression of the maximum positive and negative dP/dt compared with those of controls and 1wDM. There were no significant differences in LVDP and LVEDP among the three groups. The incidence of reperfusion-induced ventricular fibrillation (VF) was 75% for controls, 15% for 1wDM rats, and 27% for 4wDM rats. In hearts without reperfusion-induced VF, there were no differences in the three groups, between the pre- and post-ischemic values in LVDP, LVEDP, and maximum positive and negative dP/dt. These findings suggest that diabetic hearts exhibit no susceptibility to ischemia/reperfusion injury.

Transient depletion of T cells with bright CD11a/CD18 expression from peripheral circulation during acute Kawasaki disease

To clarify the activation of peripheral blood T cells in Kawasaki disease (KD) patients, we investigated whether expression of lymphocyte function-associated antigen-1 (LFA-1, CD11a/CD18) and/or intercellular adhesion molecule-1 (ICAM-1, CD54) on peripheral blood T cells increases during the acute stage. Expression of cellular adhesion molecules was measured using flow cytometry. There was a decrease in the percentage of CD3+ T cells in the bright LFA-1 alpha and LFA-1 beta population and a concomitant increase in the dim population of LFA-1 alpha and LFA-1 beta during the acute stage, in comparison with those of the convalescent stage. In addition, we observed no significant differences in ICAM-1 expression during the acute stage compared with that of the convalescent stage. In our view the present data, in conjunction with previous reports on T-cell function during acute KD, suggest that activated T cells are temporarily withdrawn from peripheral circulation during acute KD.

Occurrence of phosphonotetraglycosyl ceramide in the sea hare Dolabella auricularia

Two kinds of phosphonoglycolipids were isolated from the sea hare Dolabella auricularia. One was phosphonopentaglycosyl ceramide with the same structure as that of the phosphonoglycolipid obtained from the sea hare Aplysia kurodai. The other, phosphonotetraglycosyl ceramide, was discovered in this study. Its structure was determined to be 3-O-Me-Gal alpha 1-3(AEP-6Gal alpha 1-2)Gal beta 1-4Glc beta 1-1-ceramide. The presence of tetraglycosyl and pentaglycosyl ceramides, the backbone structures of phosphonoglycolipids in the neutral glycolipid fraction, indicate that these neutral glycolipids are precursors of the phosphonoglycolipids.

Time-dependent blockade of neurogenic plasma extravasation in dura mater by 5-HT1B/D agonists and endopeptidase 24.11

1. The delayed effects of stimulating the trigeminal ganglion unilaterally in rats and guinea-pigs were assessed by measuring the leakage of radiolabelled albumin from blood into the dura mater at intervals for up to 120 min after a 5 min stimulation period (5 Hz, 0.6 mA, 5 ms). 2. [125I]-albumin (50 microCi kg-1) was injected i.v. as a tracer 0, 20, 50, 80 or 110 min after stimulation and the animals were killed 10 min later. Extravasation of plasma protein developed for up to 90 min poststimulation. 3. To examine the mechanism underlying delayed plasma protein extravasation, CP-93,129 (5-HT1B receptor agonist, 460 nmol.kg-1), sumatriptan (5-HT1B/D receptor agonist, 24 nmol kg-1), or neutral endopeptidase 24.11 (1 nmol kg-1) were administered 45 or 75 min after trigeminal stimulation and 5 min before radiolabelled albumin. The extravasation response was reduced at 45 min. CP-23,129 also blocked extravasation when injected 25 min after capsaicin administration (1 mumol kg-1). 4. If the tracer was injected 5 min prior to electrical trigeminal stimulation, endopeptidase 24.11 (1 nmol kg-1) given 10 min before stimulation blocked the leakage (as reported previously for CP-93,129 or sumatriptan). All three compounds blocked the leakage when administered 30 min (but not 60 min) poststimulation in this paradigm. 5. The data support the previously made contention that neuropeptide release from sensory fibres mediates the plasma extravasation response following trigeminal ganglion stimulation, and that release and plasma leakage continue many minutes beyond the stimulation period. Hence, drugs that inhibit neuropeptide release (CP-93,129, sumatriptan), or enhance breakdown of neuropeptide mediators(endopeptidase 24.11) block the delayed extravasation response. Extravasation developing later than 45 min poststimulation was not neurogenically mediated.

The osteogenic potential of fracture hematoma and its mechanism on bone formation--through fracture hematoma culture and transplantation of freeze-dried hematoma

This study was conducted to provide further evidence of the inherent osteogenic potential of the fracture hematoma. The fracture hematoma was separated into its cellular and extracellular elements. The hematoma cells were cultured to study bone formation by the cellular elements alone. Bone formation acceleration factor was added to the cultured fracture hematoma cells. The cell responded to this stimulation by differentiation into chondrocytes. Fracture hematoma was freeze-dried to study the presence of osteoinduction by the extracellular factors in the fracture hematoma. The freeze-dried fracture hematoma was packaged in methylmethacrylate pellets and within capsules of hydroxyapatite. These pellets and capsules in response to extracellular humoral factors from the freeze-dried fracture hematoma. The results of experimental implantation of the cultured fracture hematoma cells revealed that these cells had the potential to differentiate into chondroblasts or osteoblasts when bone induction factors and bone acceleration factor was added to their media. These extracellular humoral factors are known to be present in the fracture hematoma.

Aneurysm of the posterior cerebral artery: report of eleven cases--surgical approaches and procedures

Eleven cases of an aneurysm of the posterior cerebral artery are reported. All 11 aneurysms were saccular, and 3 were either giant or large. The aneurysms arose from the P1 segment in three patients, the P1-P2 junction in three patients, the P2 segment in three patients, and from the P3 segment in two patients. In all, 10 patients underwent surgery. All P1 and P1-P2 junction aneurysms were treated with the pterional approach. Three P2 and two P3 aneurysms were managed by the subtemporal approach. Two small aneurysms in the series were treated by coating the aneurysmal dome, two by clipping the afferent artery, and all other saccular type aneurysms were treated by clipping the aneurysmal neck. Seven patients had either an excellent or good outcome; two had poor results; and one patient died. The operative approaches and procedures are also discussed in relation to the anatomy of posterior cerebral artery aneurysms.

[Perfusion imaging with 99mTc PPN-1011 for the assessment of myocardial area at risk and the efficacy of PTCA/PTCR in myocardial infarction and unstable angina]

The determination of the myocardium at risk before intervention and the change in that region after intervention constitute a promising measurement tool for the assessment of acute therapy. We used 99mTc PPN-1011 in 4 patients with acute myocardial ischemia (2 patients with acute myocardial infarction, 2 unstable angina) and subsequent successful reperfusion. All 4 patients had perfusion defect on the pre-reperfusion image. Perfusion abnormality on post-reperfusion image was all improved significantly compared with pre-reperfusion image, suggesting the efficacy of acute treatment in acute myocardial ischemia. We conclude that 99mTc PPN-1011 scintigraphy is useful method for the assessment of myocardial area at risk and the efficacy of PTCA/PTCR in myocardial infarction and unstable angina.

Decreased expression of CD23 on peripheral blood macrophages/monocytes during acute Kawasaki disease with coronary artery lesions

CD23 has been reported to be a macrophage/monocyte activation antigen. We focused on the expression of CD23 by peripheral blood macrophages/monocytes in 5 Kawasaki disease (KD) patients with coronary artery lesions (CAL) and compared these values with those of 35 patients without CAL. The expression of CD23 on peripheral blood macrophages/monocytes was assayed by a fluorescence-activated cell sorter using monoclonal antibodies CD23 and CD14. Absolute counts of CD23+CD14+ macrophages/monocytes in KD patients with CAL did not increase during the acute stage, while these values in KD patients without CAL increased. In addition, this decreased expression of CD23 on peripheral blood macrophages/monocytes in patients with CAL did not change during the acute stage, regardless of IVGG therapy. Our results suggest that the decreased expression of CD23 on peripheral blood macrophages/monocytes in patients with CAL is part of the regulatory system of CD23 antigen during acute KD.

Soluble ICAM-1 levels in serum during acute infectious mononucleosis

Intercellular adhesion molecule-1 (ICAM-1) has been reported as a T-cell, B-cell or macrophage/monocyte activation antigen. We investigated whether soluble ICAM-1 levels in serum increased during the acute stage in 11 patients with infectious mononucleosis (IM). Serum ICAM-1 levels were measured by a double determinant immunoassay using 2 monoclonal antibodies in the FAST system. Serum ICAM-1 levels in patients with IM increased during the acute stage. There was a positive correlation between serum ICAM-1 levels and absolute counts of peripheral blood mononuclear cells. Our results suggest that the elevated serum ICAM-1 levels are based on the increased counts of activated peripheral blood mononuclear cells and that ICAM-1 is a part of the regulatory system of immune reactions during acute IM.

Role of liver-type glucose transporter (GLUT2) in transport across the basolateral membrane in rat jejunum

To obtain information on the regulation of glucose transport across the basolateral membrane (BLM) of intestinal epithelial cells, we measured the number of [3H]cytochalasin B binding sites and the level of liver-type glucose transporter (GLUT2) protein in the BLM in the jejunum of rats (i) with diabetes (ii) given a high-carbohydrate diet or (iii) with experimental hyperglycemia (12 h infusion of a high-glucose solution). A glucose uptake and the number of D-glucose inhibitable [3H]cytochalasin B binding sites in BLM vesicles were significantly increased in all three conditions. Western blot analysis showed that the amount of GLUT2 protein in BLM vesicles was increased in rats with diabetes and those given a high-carbohydrate diet, but not in those with experimental hyperglycemia. These results suggest that there is a mechanism for rapid regulation of glucose transport in the BLM that does not depend on change in the amount of GLUT2.

UK-14,304, R(-)-alpha-methyl-histamine and SMS 201-995 block plasma protein leakage within dura mater by prejunctional mechanisms

Intravenous administration of an alpha-adrenoceptor agonist, UK-14,304, a histamine H3 receptor agonist, R(-)-alpha-methyl-histamine (alpha-MeHA) or SMS 201-995 (a synthetic octapeptide analogue of somatostatin), blocked plasma protein (125I-albumin) extravasation within rat and/or guinea pig dura mater following unilateral electrical trigeminal ganglion stimulation or capsaicin administration. The extravasation caused by the administration of the neuropeptide mediator, substance P, was not inhibited by any of the three compounds. Blockade by UK-14,304 was completely antagonized by pretreatment with the highly selective alpha 2-antagonist, idazoxan, as was alpha-MeHA by pretreatment with the highly selective histamine H3 antagonist, thioperamide. Taken together, the results are consistent with blockade by prejunctional alpha 2, histamine H3 and probably somatostatin receptors which may be coupled to inhibition of neuropeptide release. Because 5-HT1-like agonists, which are useful for treating migraine and related headaches, share similar inhibitory properties in this in vivo model, the significance of prejunctional alpha 2, histamine H3 and somatostatin receptors to treatment of vascular headaches is suggested.

Hypophyseal metastatic hypernephroma mimicking a pituitary adenoma. Case report

A patient with a remote history of nephrectomy for hypernephroma presented a visual field defect with hypopituitarism. Neuro-imaging studies showed a highly vascularized sellar mass with suprasellar extension. Surgery, which was performed via the subfrontal approach, disclosed the pituitary tumor to be a hypernephroma. Although anterior pituitary involvement is rare, chiasmal compression is much rarer in metastatic pituitary carcinomas, a review of previously reported cases of metastatic pituitary hypernephroma and our own case indicated that pituitary metastasis from this carcinoma, in contrast to other metastatic pituitary tumors, often mimics pituitary adenoma.

Capillary gas chromatographic method for the determination of the thromboxane A2 receptor antagonist S-1452 and its metabolites in human plasma

A capillary gas chromatographic method for the determination of a newly developed thromboxane A2 antagonist, S-1452, and its metabolites in human plasma has been developed. This nitrogenous compound was detected as the free acid (+)-S-145 using a nitrogen-phosphorus detector. The two metabolites bisnor-(+)-S-145 and tetranor-(+)-145 were also assayed. The three compounds, which all possess carboxylic acid group, were converted into their hexafluoro-2-propyl esters with hexafluoropropan-2-ol-pentafluoropropionic anhydride as reagent. The esterification resulted in a decreased background response from the detector, and hence higher sensitivity and better precision. The glucuronides of the three compounds were also assayed after alkaline hydrolysis. The plasma concentration of the glucuronide of I was more than twice that of the free acid. This method allows determination of the three compounds at more than 2 ng/ml with a precision of 2-6% and an accuracy variation of less than +/- 5%. The analysis was performed within 2 min after injection to assay the sample rapidly from the Phase I test. The method is suitable for pharmacokinetic studies.

Capillary gas chromatographic method for the determination of the thromboxane A2 receptor antagonist S-1452 and its metabolites in human urine

A capillary gas chromatographic method using a sulphur-specific detector (Hall's electrolytic conductivity detector) was established to determine the thromboxane A2 antagonist S-1452 and its metabolites in human urine. The target species were the free acid (+)-S-145 of the drug and its nine metabolites: the three hydroxyl forms of (+)-S-145 (I, II and III), bis-nor-(+)-S-145 (IV) the hydroxylated forms of IV (V and VI), tetranor-(+)-S-145 (VII) and the hydroxylated forms of VII (VIII and IX). These ten compounds, which have the same sulphur-containing functional group in common, were determined simultaneously. Their conjugated forms, which were assumed to be glucuronides, were also assayed after hydrolysis. The first derivatization was esterification with diazomethane. The second, for the hydroxylated compounds, was trimethylsilylation with bis(trimethylsilyl)trifluoroacetamide. The ten analytes appeared as separate peaks without mutual interference during 5 min. Hall's detector distinguished the ten analytes selectively from the other urinary components, which removed the need for complex clean-up procedures and led to higher sensitivity with a lower noise level. The method is sensitive enough for the assay of substances present at more than 0.1 micrograms/ml of urine. All the compounds could be determined with a high level of precision and accuracy, with 2-5% relative standard deviation and within +/- 5% deviation from the actual value. Day-to-day measurements verified the reproducibility of the method. Recovered substances were quantified by following the time course, and the analytical data together with previously obtained plasma data clarified the metabolism pharmacokinetically.

[The prevalence and the clinical characteristics of silent myocardial ischemia detected by stress thallium scintigraphy]

The prevalence of silent myocardial ischemia was retrospectively assessed in a group of 100 consecutive patients with angiographically proved coronary artery disease, and diagnostic ECG, by symptom-limited exercise thallium-201 scintigraphy. Twenty-four patients had no evidence of ischemia despite adequate exercise level. So among 76 patients with exercise induced ischemia, only 33 patients (43%) stopped exercise due to anginal pain (symptomatic ischemia: Group 3). And 43 patients with asymptomatic ischemia composed of 23 patients (30%) with ECG change (Group 2B) and 20 patients (26%) without ECG change (Group 2A). Patients background including the history of old myocardial infarction and diabetes mellitus, were similar among Group 2A, 2B, and Group 3. And our major observation was that the extent and severity of quantified SPECT perfusion defects was nearly identical between 3 groups Thus in this study group, there was a rather high prevalence rate of silent ischemia (57%) by exercise thallium-201 criteria. Patients with silent ischemia, associated with positive and negative exercise ECG findings, and those with exercise angina had similar background and comparable amount of jeopardized myocardium.

Balloon catheter with check valves for experimental relief of acute aortic regurgitation

To evaluate the ability of a newly designed balloon catheter with check valves to temporarily relieve hemodynamic deterioration in acute aortic regurgitation, we produced an experimental model of acute aortic regurgitation in closed-chest dogs using endomyocardial biopsy forceps. Aortic regurgitation was produced until an increase in aortic pulse pressure of over 50% was achieved. Left ventricular end-diastolic pressure rapidly increased after the production of aortic regurgitation. Immediately after the catheter began functioning, pulse pressure decreased from 133 +/- 1 to 78 +/- 5 mm Hg (mean +/- SEM) and left ventricular end-diastolic pressure also decreased from 26 +/- 1 to 13 +/- 1 mm Hg. These effects lasted as long as the catheter functioned. Although a mild (21 +/- 8 mm Hg) pressure gradient between the left ventricular peak systolic pressure and the aortic peak systolic pressure was observed when this catheter was used, forward stroke volume was no less than in the group in which the catheter had not been used. These findings suggest that the balloon catheter with check valves may effectively reduce aortic regurgitation.