Evaluation of the dye-protein tracers in pathophysiology of the blood-brain barrier

1. Sodium fluorescein and Evans Blue, commonly used tracers in the study of blood-brain barrier disturbances, revealed considerable differences in their respective protein binding capacity in the plasma, passage through the barrier and in the rate of their elimination from the brain parenchyma. 2. In the plasma a considerable portion of the sodium fluorescein remains free and behaves like a micromolecular barrier tracer. On the other hand, almost complete binding of the Evans Blue to albumin confers to it properties of a protein tracer. 3. Following the extravasation of the tracers, the sodium fluorescein is relatively soon eliminated, whereas Evans Blue remains in the cellular elements of the brain parenchyma for a considerable time, although the protein moiety of the tracer is removed much sooner from the cytoplasm of glial cells, presumably by the lysosomal digestion.

Adrenal nodularity and somatic mutations in primary aldosteronism: one node is the culprit?

CONTEXT

Somatic mutations in genes that influence cell entry of calcium have been identified in aldosterone-producing adenomas (APAs) of adrenal cortex in primary aldosteronism (PA). Many adrenal glands removed for suspicion of APA do not contain a single adenoma but nodular hyperplasia.

OBJECTIVE

The objective of the study was to assess multinodularity and phenotypic and genotypic characteristics of adrenals removed because of the suspicion of APAs.

DESIGN AND METHODS

We assessed the adrenals of 53 PA patients for histopathological characteristics and immunohistochemistry for aldosterone (P450C18) and cortisol (P450C11) synthesis and for KCNJ5, ATP1A1, ATP2B3, and CACNA1D mutations in microdissected nodi.

RESULTS

Glands contained a solitary adenoma in 43% and nodular hyperplasia in 53% of cases. Most adrenal glands contained only one nodule positive for P450C18 expression, with all other nodules negative. KCNJ5 mutations were present in 22 of 53 adrenals (13 adenoma and nine multinodular adrenals). An ATP1A1 and a CACNA1D mutation were found in one multinodular gland each and an ATP2B3 mutation in five APA-containing glands. Mutations were always located in the P450C18-positive nodule. In one gland two nodules containing two different KCNJ5 mutations were present. Zona fasciculata-like cells were more typical for KCNJ5 mutation-containing nodules and zona glomerulosa-like cells for the other three genes.

CONCLUSIONS

Somatic mutations in KCNJ5, ATP1A1, or CACNA1D genes are not limited to APAs but are also found in the more frequent multinodular adrenals. In multinodular glands, only one nodule harbors a mutation. This suggests that the occurrence of a mutation and nodule formation are independent processes. The implications for clinical management remain to be determined.

Application of percutaneous transluminal coronary angioplasty to coronary arterial stenosis in Kawasaki disease

BACKGROUND

Percutaneous transluminal coronary angioplasty (PTCA) has rarely been performed on patients with coronary lesions that result from Kawasaki disease. In this study, we retrospectively evaluated the effectiveness of PTCA in five patients with coronary arterial stenosis that resulted from Kawasaki disease and reviewed previous reports for possible indicators of PTCA effectiveness.

METHODS AND RESULTS

Five patients, ranging in age from 2 to 16 years (median 8 years) underwent conventional PTCA for localized stenosis. The lesion targeted for PTCA was located in the middle right coronary artery of three patients and in the left anterior descending artery in two patients. In four of the five patients, PTCA was angiographically effective, with stenosis rates improving from 84 +/- 10% to 33 +/- 11% (P<.05). When the previously reported cases of six similar patients were taken into consideration, the only predictor of successful PTCA seemed to be the time elapsed between the onset of Kawasaki disease and performance of this procedure.

CONCLUSIONS

In cases in which patients show significant localized stenosis as a result of Kawasaki disease, PTCA should be attempted within 6 to 8 years of the onset of the disease. Additionally, intravascular ultrasound imaging was found to be a useful tool for evaluating internal morphology before and after PTCA. In older patients with coronary calcification, other alternatives to PTCA, such as the use of a rotablator or an atherectomy catheter, should be considered.

Electromyographic analysis of shoulder joint function of the biceps brachii muscle during isometric contraction

Surface electromyography was performed for both heads of the biceps brachii in 11 healthy men while the muscles were under 30% maximum isometric shoulder flexion and abduction. Elbow related biceps activity was minimized by using a brace locked in neutral forearm rotation. Electromyographic activity was normalized as a percentage of maximal muscle contraction during 24 shoulder motions. Electromyographic activity was detected in all motions examined, suggesting that the biceps muscle acts as a flexor and an abductor of the shoulder. Both heads of the biceps muscle had higher activities during external rotation than during internal rotation for most motions. Activities of both heads increased with arm elevation, but showed little dependence on elbow position. The long head was still active during internal rotation of the shoulder. These findings also suggest that the biceps muscle is a flexor and an abductor of the shoulder, and that the long head can act as a humeral head stabilizer in superior and anterior directions. Muscle fatigue of the biceps and the deltoid muscle also was determined at 30% of maximum isometric flexion. All muscles had significantly decreased mean power frequency and turns count, and increased amplitude and integrated electromyography. The rate of decrease in mean power frequency was larger for the biceps than for the deltoid muscle, and the rate of increase in amplitude was larger for the long head of the biceps than for the short head or for the deltoid muscle. These findings suggest that the long head of the biceps must increase its mechanical output to keep the arm in elevation to a greater extent than do the short head and the deltoid muscle. This may be one of the causes of tendinitis or rupture of the long head.

Effect of hydrogen bonding on electronic spectra and reactivity of flavins

Riboflavin tetrabutyrate undergoes characteristic spectral changes, in both the first and second absorption band regions, upon hydrogen bonding with trichloroacetic acid of trifluoroacetic acid. On the basis of the calculated electron densities, hydrogen bonding at the heteroatoms of the isoalloxazine nucleus is considered to occur with increasing concentrations of the proton donor, first at N(1), then at O(12), O(14), and N(3)H, and finally at N(5). The idea that the major effect of the hydrogen bonding at the N(1), N(3)H, and oxygen atoms of the flavin nucleus is to facilitate the electrophilicity of the N(5) position, which was predicted by molecular orbital calculations, was supported by the observation that the hydrogen-bonded flavin in its triplet state abstracts hydrogen from the donor N-benzyl-n,n'-dimethylethylenediamine at a faster rate than do the non-hydrogen-bonded species in CCI4. The implications of the present study in the spectroscopic and catalytic properties of flavoproteins are briefly discussed.

Cloning, sequencing, and high level expression of the genes encoding adenosylcobalamin-dependent glycerol dehydrase of Klebsiella pneumoniae

The gld genes encoding adenosylcobalamin-dependent glycerol dehydrase of Klebsiella pneumoniae were cloned by cross-hybridization with a DNA fragment of Klebsiella oxytoca diol dehydrase genes. Since the Escherichia coli clones isolated did not show appreciable enzyme activity, plasmids for high level expression of cloned genes were constructed. The enzyme expressed in E. coli was indistinguishable from the wild-type glycerol dehydrase of K. pneumoniae by the criteria of polyacrylamide gel electrophoretic, immunochemical, and catalytic properties. It was also shown that the recombinant functional enzyme consists of Mr 61,000, 22,000, and 16, 000 subunits. Sequence analysis of the genes revealed four open reading frames separated by 2-12 bases. The sequential three open reading frames from the first to the third (gldA, gldB, and gldC genes) encoded polypeptides of 555, 194, and 141 amino acid residues with predicted molecular weights of 60,659(alpha), 21,355(beta), and 16,104(gamma), respectively. High level expression of these three genes in E. coli produced more than 14-fold higher level of fully active apoenzyme than that in K. pneumoniae. It was thus concluded that these are the genes encoding the subunits of glycerol dehydrase. The deduced amino acid sequences of the three subunits were 71, 58, and 54% identical with those of the alpha, beta, and gamma subunits of diol dehydrase, respectively, but failed to show any apparent homology with other proteins.

Idebenone improves cerebral mitochondrial oxidative metabolism in a patient with MELAS

We report a 36-year-old man with MELAS in whom a 5-month course of high-dose oral idebenone, a derivative of coenzyme Q10, increased markedly cerebral metabolic ratio of oxygen and oxygen extraction fraction without increased cerebral blood flow with PET. The results indicate that idebenone improves mitochondrial oxidative metabolism in the brain and suggest a therapeutic potential of idebenone for MELAS.

Relationship between molecular structures of sugars and their ability to stimulate the release of glucagon-like peptide-1 from canine ileal loops

The structure-activity relationship of sugars inducing secretion of glucagon-like peptide-1 from the gut was examined using intestinal loops prepared from the terminal portion of the ileum of dogs. The plasma glucagon-like peptide-1 concentration in a mesenteric vein draining only the looped region of the intestine was increased after infusion of 139 mmol/l solutions of D-glucose, D-galactose, D-glucuronic acid, 3-0-methyl-D-glucose, maltose, sucrose or maltitol into the intestinal lumen, but not after infusion of solutions of D-fructose, D-fucose, D-mannose, D-xylose or lactose. The increases in plasma glucagon-like peptide-1 concentration correlated with the corresponding increases in glucagon-like immunoreactivity induced by these sugars. The plasma glucose level of the regional mesenteric vein increased significantly from the basal level after instillation of D-glucose, but not after instillation of other sugars. It is suggested that cells of the gut have a glucose sensor for release of products of the glucagon gene and that this sensor has specific steric requirements. The sugars that induced glucagon-like peptide-1 release share the molecular features of electron density near C(6), an equatorial hydroxyl at C(2), and an axial hydroxyl at C(1), which could account for their recognition by the glucose sensor to initiate the releases of glucagon-like peptide-1 and glucagon-like immunoreactivity.

Hydrogen bonding of flavoprotein. I. Effect of hydrogen bonding on electronic spectra of flavoprotein

The effect of hydrogen bonding on the transition energy and the oscillator strength of the isoalloxazine nucleus of flavins was studied by the molecular orbital method. Among the possible hydrogen bondings examined, characteristic spectral shifts were found for the hydrogen bondings at N(1) and N(5) of the nucleus. The hydrogen bonding at N(1) resulted in the shift of the first absorption band towards blue and that of the second one towards red. On the other hand, the hydrogen bonding at N(5) resulted in the shifts of both the first and the second band towards red. The spectral characteristics reported on Clostridium MP and Desulfovibrio vulgaris flavodoxin coincided with the calculated results. The application of the calculated results to D-amino acid oxidase (D-amino acid: oxygen oxidoreductase (deaminating), EC 1.4.3.3) led to the conclusion that hydrogen bonding occurs at O(12), N(3)H, O(14) and N(5) of the isoalloxazine nucleus. The occurrence of hydrogen bondings at O(12), N(3)H, and O(14) is favorable for N(5) of the isoalloxazine nucleus to accept electron from an electron donor.

Association study of TRAF1-C5 polymorphisms with susceptibility to rheumatoid arthritis and systemic lupus erythematosus in Japanese

OBJECTIVE

The primary aim of this study was to investigate the association of polymorphisms of TRAF1-C5, a newly identified rheumatoid arthritis (RA) risk locus in Caucasians, with susceptibility to RA and systemic lupus erythematosus (SLE) in Japanese populations. Gene expression levels of TRAF1 and C5 to assess the functional significance of genotypes were also analysed.

METHODS

A multicentre association study consisting of 4 RA case-control series (4397 cases and 2857 controls) and 3 SLE case-control series (591 cases and 2199 shared controls) was conducted. Genotyping was performed using TaqMan genotyping assay for two single nucleotide polymorphisms (SNPs) that showed the best evidence of association in the previous Caucasian studies. Quantifications of TRAF1 and C5 expression were performed with TaqMan expression assay.

RESULTS

Significant differences in allele frequency for both SNPs were observed between RA and control subjects (combined odds ratio = 1.09), while no significant difference was detected between patients with SLE and controls. Interestingly, alleles rs3761847 A and rs10818488 G had increased the risk for RA in the present study, while they decreased the risk in the original studies. A significant difference was found between risk allele carriers and non-carriers of rs10818488 for the expression level of TRAF1 in phorbol myristate acetate-stimulated lymphoblastoid cell lines (p = 0.04).

CONCLUSION

Association of TRAF1-C5 locus with RA susceptibility was detected in the Japanese populations with modest magnitude, while no significant association was observed for SLE. Significant positive effect of genotype on the expression of TRAF1 might support the genetic association between TRAF1 and RA.

Apoptosis as a possible cause of wall thinning in end-stage hypertrophic cardiomyopathy

A 15-year-old boy with hypertrophic cardiomyopathy died of congestive heart failure with progressive left ventricular wall thinning with poor systolic function. Microscopic examination revealed patchy fibrosis in the ventricular myocardium with wall thinning, and immunohistochemical evaluation of apoptosis showed apoptotic cells and bodies in the destroyed myocytes along the border between the fibrotic area and myofibril.

Increased tacrolimus trough levels in association with severe diarrhea, a case report

It is well known that during diarrhea episodes decreased cyclosporine and tacrolimus levels are often observed, usually requiring an increase in dose. An increase in tacrolimus trough levels is infrequently recognized as a potential cause of the adverse effect of severe diarrhea. Herein, we report the case of a renal transplant patient who displayed increased tacrolimus trough levels during an episode of gastroenteritis with severe diarrhea. The patient is 32-year-old male who received a renal transplant from his mother. Immunosuppression was initiated with tacrolimus in combination with mycophenolate mofetil and prednisone. The postoperative course was uneventful. The function of the transplanted kidney was normal. Eight months after transplantation he presented to our hospital with a history of high fever, abdominal pain, nausea and severe diarrhea. He was admitted with a diagnosis of enterocolitis of unknown etiology. The blood trough level of tacrolimus had increased from 6.7 ng/mL to 28.7 ng/mL after the onset of diarrhea. A therapeutic trough level of tacrolimus was reached 6 weeks after complete relief of diarrhea. Tacrolimus shows large variability in bioavailability after oral administration, both due to intestinal metabolism by cytochrome P450 (CYP3A4) and active secretion from enterocyte into intestinal lumen by P-glycoprotein. The epithelial cells of the intestine, may be destroyed abrogating P-glycoproteins during the course of enterocolitis, thereby increasing the levels of tacrolimus. It is recommended to monitor trough levels of tacrolimus during severe diarrhea of any nature to prevent tacrolimus-related complications.

Dilatation mechanism of balloon angioplasty in children: assessment by angiography and intravascular ultrasound

PURPOSE

Little information is available about the dilatation mechanism in children. This prospective study aimed to (1) evaluate the dilatation mechanism of balloon angioplasty in children with arterial stenosis, and (2) compare the morphological changes seen by intravascular ultrasound (IVUS) and angiography.

METHODS

Twenty consecutive patients, who had undergone a total of 23 procedures, were examined before and immediately after balloon angioplasty with a 4.3 Fr, 30 MHz rotational tip IVUS system. The lesions for IVUS study had resulted from coarctation of the aorta in six patients, pulmonary arterial stenosis in five, Blalock-Taussig shunt stenosis in three, subclavian artery stenosis in two, renal artery stenosis in two, coronary artery stenosis in one and ductus arteriosus in one.

RESULTS

Four distinctive morphological types were identified: type I with arterial stretching, type IIa with superficial tearing, type IIb with deep intimal-medial tearing, type III with flap formation, and type IV with dissection. The diameter of the narrowest site before and after balloon angioplasty increased significantly from 2. 1 +/- 1.4 mm to 4.6 +/- 3.4 mm (p < 0.001). Eighteen of the 23 angioplasty procedures (78%) were considered to be successful, with a dilatation ratio of more than 50%. In most patients with successful dilatation, non-stretch mechanisms such as tearing, flap formation, or dissection were found. The positive percent (70%) of non-stretch mechanisms seen by IVUS was significantly higher than the positive findings (39%) by angiography (Chi2 = 6.47, p < 0.02).

CONCLUSIONS

Non-stretch morphology of the arterial wall may be a common mechanism of dilatation after balloon angioplasty in children with arterial stenosis. IVUS is a useful modality for evaluating the effectiveness of balloon angioplasty and the mechanism of dilatation in individual cases.

Progressive vascular lesions in Williams-Beuren syndrome

We report two patients with Williams-Beuren syndrome. The first patient showed no evidence of coarctation of the aorta at the first examination. Seven years later, she developed coarctation of the aorta. In the second patient, we found the progression of renal artery stenosis by serial angiography. We report that vascular lesions may be progressive in Williams-Beuren syndrome.

Magnetic resonance imaging and brain-stem auditory evoked potentials in neuro-Behçet's disease

We studied central nervous system lesions in patients with neuro-Behcet's disease using magnetic resonance imaging (MRI) of the brain and recording of brain-stem auditory evoked potentials (BAEPs). MRI revealed abnormal findings in seven of eight patients. MRI studies demonstrated extensive regions with high intensity signal in the brain stem and/or basal ganglia on T2-weighted images obtained during the acute stage of the disease in three patients. One of these patients had a strongly gadolinum-enhanced round lesion in the lower pons. In four of the other five patients with chronic disease, brain-stem atrophy was observed on T1-weighted images. Atrophic changes were more severe in the brain stem than in the cerebellum. Abnormal BAEPs were observed in three patients and consisted of prolongation of interpeak latency of waves III-V and defects of wave III or V. Abnormal BAEPs were recorded in patients with severe inflammatory changes or progression of atrophic changes in the brain stem. Our findings show that MRI and BAEPs are useful in detecting the presence and assessing the degree of neurological involvement in patients with neuro-Behçet's disease.

Intramuscular spindle cell lipoma: Case report and review of the literature

Spindle cell lipoma (SCL) is a relatively rare adipocytic neoplasm and is histologically characterized by a mixture of uniform spindle cells and mature fat cells. It occurs predominantly in male patients aged 45-65 years, and in most cases it arises in the subcutaneous tissue of the neck or shoulder. Although the neoplasm sometimes affects unusual sites, only three cases have been reported in which the lesion was intramuscular. Here we present a case of SCL arising in skeletal muscle; to our knowledge, the first report in 10 years. The tumor occurred in the neck of a 50-year-old male patient. Magnetic resonance imaging (MRI) revealed a lipomatous tumor within the right trapezius muscle. The tumor was localized beneath the fascia and was excised completely at surgery. Histologically, the tumor was typical of a spindle cell lipoma with no evidence of malignancy. An immunohistochemical study revealed all spindle cells were strongly positive for CD34. Differential diagnosis is discussed with a review of the literature.

Studies in a model system on the effect of hydrogen bonding at hetero atoms of oxidized flavin on its electron acceptability

The effect of hydrogen bonding at hetero atoms of oxidized flavin on its electron acceptability was studied by the ab initio molecular orbital method. The calculations were carried out for all possible lumiflavin-H2O complexes and for some lumiflavin-formamide complexes. Calculated data showed that the magnitudes of hydrogen bonding energy at the hetero atoms are in the order of N(3)H greater than N(5) greater than O(12) greater than N(1) greater than O(14). It was found that the atomic orbital coefficient of the lowest unoccupied molecular orbital is the largest at N(5) and that hydrogen bonding at N(1), N(5), O(12), and O(14) increases the electron acceptability of the oxidized flavin at N(5), while hydrogen bonding at N(3)H decreases it.

Late persistent expressions of ICAM-1 and VCAM-1 on myocardial tissue in children with lymphocytic myocarditis

BACKGROUND

Both intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) have been implicated in cardiac allograft rejection. However, there is little information about the relationship between the expression of these adhesion molecules and myocarditis in children.

METHODS AND RESULTS

Immunoreactivities of ICAM-1 and VCAM-1 were examined by enzyme immunoassay in 31 biopsy specimens obtained from 11 pediatric patients with biopsy-proven myocarditis or cardiomyopathy. Five of the 11 patients had clear evidence of acute myocarditis. The other 6 had ECG abnormalities identified by mass screening for heart disease, and subsequently had been histologically diagnosed as having non-specific cardiomyopathy. The period between onset of myocarditis or identification of ECG abnormality and immunohistochemical studies was 23 to 60 days and 8 months to 3 years, respectively. Expression of ICAM-1 and VCAM-1 was assessed by counting ICAM-1 and VCAM-1 positive vessels and dividing by the total number of vessels. ICAM-1 was significantly present on 81% (P < 0.01) of myocardial tissue samples in the 5 patients with healing-stage acute myocarditis, and on 45% (P < 0.05) in the remaining 6 patients with non-specific cardiomyopathy, compared with 24% in control specimens obtained from right ventricular muscle resected at surgery for tetralogy of Fallot. VCAM-1 was also present on 50% (P < 0.05) of the samples from the 5 patients with acute myocarditis, but was not present in those with non-specific cardiomyopathy.

CONCLUSION

This persistent expression of ICAM-1 suggests that myocardial cell damage may persist immunologically for a long period in myocarditis. In addition, immunostaining for these adhesion molecules may be diagnostic value in clinically silent lymphocytic myocarditis and chronic cardiomyopathy.

Percutaneous transluminal coronary angioplasty for Kawasaki disease: a case report and literature review

A 31-month-old boy developed right coronary artery stenosis after Kawasaki disease for which he underwent percutaneous transluminal coronary angioplasty (PTCA). The narrowing of the right coronary artery was successfully dilated by angioplasty without apparent complication. This case suggests that PTCA may have a potential advantage as a temporary method to postpone the aortocoronary bypass surgery in a child with coronary artery stenosis due to Kawasaki disease. However, strict patient selection is recommended for coronary angioplasty.

Clinical features of aortic arch anomaly with malalignment ventricular septal defect

The clinical features and outcome after various surgical procedures on 9 patients with coarctation or interruption of the aortic arch and malalignment ventricular septal defect (group 1) were compared with those of 9 patients with the arch anomaly without malalignment ventricular septal defect (group 2). Cardiomegaly and metabolic acidosis were prominent in group 1. Five of the 9 patients in group 1 died in the immediate postoperative period (56% mortality), but no operative deaths occurred among 8 patients in group 2 (p less than 0.01). The ratio of left ventricular outflow tract to ascending aortic diameter was 0.59 +/- 0.09 in group 1 and 1.03 +/- 0.11 in group 2 (p less than 0.01). Three of 4 patients with a ratio of less than 0.6 died, but no operative deaths occurred among the 6 patients who had a palliative operation and in whom the ratio was more than 0.6. These data suggest that left ventricular outflow tract obstruction is critical when the ratio of left ventricular outflow tract to ascending aortic diameter is 0.6 or less. The presence of severe left ventricular outflow tract obstruction necessitates modification of the present surgical strategy.

Clinical evaluation of taste dysfunction using a salt-impregnated taste strip

We have used special tests to investigate taste function in detail. To evaluate acuity for a salty taste, we used a paper with salt crystals, Salsave. The procedure is simple and takes only a few minutes. We analyzed the relationships between the magnitude of the threshold of response to this test and the results of other taste function tests in 126 patients who visited our clinic. The mean magnitude of the response to Salsave significantly correlated with the results of other taste tests. Thus, this is a useful method for screening the detection and recognition threshold of a salty taste.

Subcutaneous phaeohyphomycosis caused by Phaeoacremonium rubrigenum in an immunosuppressed patient

BACKGROUND

Phaeohyphomycosis refers to infection by dematiaceous fungi with pigmented hyphae or yeast-like cells in the tissue. In humans, this disease is usually considered to be an opportunistic infection. The causal agents of phaeohyphomycosis include numerous species belonging to different genera and they are increasing as a result of the development of intensive medical therapy.

OBSERVATION

We report the case of a 61-year-old Japanese female under corticosteroid treatment for malignant rheumatoid arthritis. An asymptomatic subcutaneous tumor developed on the back of her left foot. Histological examination of the excised material revealed mixed cell granuloma (H&E) and the presence of branched hyphal elements (periodic acid-Schiff). A fungus grown in pure culture was identified as Phaeoacremonium rubrigenum.

CONCLUSION

The hyphomycete genus, Phaeoacremonium, was proposed in 1996 by Crous et al. Three species belonging to this genus have been isolated from clinical specimens: P. inflatipes, from a human toenail, human synovial fluid and human mycetoma of the foot, P. parasiticum, from a subcutaneous lesion on a kidney transplant patient and several other sources, and P. rubrigenum, from a human patient with pneumonia. To our knowledge, however, this is the first report of phaeohyphomycosis caused by Phaeoacremonium rubrigenum.