Increased transendothelial permeation of albumin by high glucose concentration

Vascular endothelial cells, which are polyfunctional, play an important role in the pathogenesis of diabetic complications. The increase in vascular permeability, ie, regulated by vascular endothelial cells, has been reported in patients with diabetes mellitus complicated by angiopathy. To determine the role of hyperglycemia in endothelial cell permeability, we examined the effect of high concentrations of glucose on the permeability of cultured bovine aortic endothelial cells. The permeations of albumin and fluorescein-labeled dextran (FD) across endothelial cell monolayers were increased when cultured with a high concentration of glucose (400 mg/dL). This increased permeation of albumin but not FD was temperature-dependent and was partially reduced by adding 100 mumol/L ponalrestat (ICI 128,436, Statil; ICI, Cheshire, UK), which is an aldose reductase inhibitor. Stimulation or inhibition of Na,K-adenosine triphosphatase (ATPase) in bovine aortic endothelial cells failed to alter their permeability. These findings suggest that high concentrations of glucose enhance transendothelial permeability of albumin in part by activating the polyol pathway, but independently of Na,K-ATPase activity.

Immunoblot analysis using recombinant protein of the 180 kD bullous pemphigoid antigen NC16a domain as an aid to the diagnosis of atypical subepidermal autoimmune bullous skin diseases

We have recently developed a novel immunoblotting system using bacterial fusion protein containing the NC16a domain, the most immunogenic region, of the 180 kD bullous pemphigoid (BP) antigen, which was shown to be highly sensitive and specific method to detect the antigen and to be very useful for the diagnosis of BP. In this study, using this immunoblot assay, we investigated sera obtained from 26 patients who showed atypical clinical features. The sera of these cases showed in general very weak reactivity with the basement membrane zone on immunofluorescence, and very weak and variable results in detection of either the 230 kD or 180 kD BP antigen with immunoblotting of human epidermal extracts. However, with immunoblotting of the BP180 NC16a domain fusion protein, this protein was detected by 21 out of the 26 cases. These results indicated that this new assay system is the most sensitive method to detect BP antigen, and should be very useful for the diagnosis for these atypical cases.

Third-order nonlinear optical properties of sol-gel-derived V(2)O(5), Nb(2)O(5), and Ta(2)O(5) thin films

The third-order nonlinear optical properties of sol-gel-derived V(2)O(5), Nb(2)O(5), and Ta(2)O(5) thin films have been investigated by the third-harmonic-generation method, and the effect of the metal-oxygen bond length on the third-order nonlinear optical susceptibility χ((3)) has been examined. The χ((3)) values of V(2)O(5), Nb(2)O(5), and Ta(2)O(5) thin films were 1.1 × 10(-11), 1.3 × 10(-12), and 6.1 × 10(-13) esu, respectively, which corresponds to an increase in the average bond length I(b) of the order of V-O (I(b) = 0.183 nm), Nb-O (I(b) = 0.200 nm), and Ta-O (I(b) = 0.204 nm). The current and previous results indicate that χ((3)) of these transition metal oxides with the empty d orbitals is dominated mainly by the metal-oxygen bond length rather than the valence of the metal cation. It is predicted on the basis of Lines' model that transition metal oxides with the shortest I(b) exhibit the highest χ((3)), whereas nontransition metal oxides with the longest I(b) exhibit the highest χ((3)).

Characterisation of a desmocollin isoform (bovine DSC3) exclusively expressed in lower layers of stratified epithelia

Desmocollins are cadherin-like glycoproteins involved in cell adhesion and plaque formation in desmosome junctions. Three distinct isoforms, the products of different genes, have been found in bovine tissues. We have reported previously that one of these, DSC3, is expressed only in basal and lower suprabasal layers of stratified epithelia. Using RT-PCR we have now obtained the complete cDNA coding sequence of mature bovine DSC3. It has alternatively spliced ‘a’ and ‘b’ forms found in other desmocollins but is unique in having a 43 instead of a 46 base pair exon. We have characterised a monoclonal antibody, 07–4G, which is specific for the Dsc3 protein, recognising an epitope in the extracellular domain. Immunofluorescent staining with 07–4G confirms that this isoform is found only in stratified epithelia, being strongly expressed in the basal cell layers of these tissues. The intensity of expression fades gradually in the suprabasal layers and disappears completely below the upper limit of desmosome expression. These results suggest that Dsc3 plays an important role in cell epithelial differentiation.

The evolutionary relationships between homologs of ribosomal YL8 protein and YL8-like proteins

We previously reported the sequence of YL8A, one of the two genes encoding yeast ribosomal protein YL8. With the aim of conducting an evolutionary study we have cloned and sequenced a second gene, YL8B. The disruption of both genes is lethal. Unlike other duplicated ribosomal protein genes, each open reading frame is interrupted by two introns containing long conserved sequences. A comparison of nucleotide and amino-acid sequences reveals that the duplication of the YL8 gene must have occurred very recently. Alignment and phylogenetic analysis of the amino-acid sequences of YL8-related proteins from various species show the existence not only of YL8 ribosomal proteins but also of a family of YL8-like proteins. These are present in at least three species of yeast and seem to be functionally distinct from ribosomal proteins.

Desmoyokin/AHNAK protein localizes to the non-desmosomal keratinocyte cell surface of human epidermis

Desmoyokin, a high-molecular-weight protein of 680 kD with a 170-nm-long dumbbell shape, was originally thought to be localized to the desmosomal attachment plaque and to work as a kind of stabilizer of desmosomes. Recently, desmoyokin was shown to be widely detected in many types of cells that do not possess desmosomes. The purpose of the present study was to elucidate the precise localization and possible function of desmoyokin in human epidermis. In 0.2-micron ultrathin cryosections of human skin for immunofluorescence, anti-desmoyokin antibody showed a ladder-like staining pattern along the cell surface, whereas anti-desmocollin and anti-desmoplakin antibodies as controls showed a discontinuous dotted staining pattern, indicating their distinct localization. Post-embedding immunoelectron microscopy with cryofixation and cryosubstitution revealed that desmoyokin was localized mainly along the non-desmosomal and non-hemidesmosomal plasma membrane, but not to the desmosomes and hemidesmosomes themselves. This localization was further confirmed by double-labeling immunoelectron microscopy with antibodies against desmocollin, desmoplakin, or bullous pemphigoid antigen. Results indicate that desmoyokin was not localized to the desmosomes themselves as previously considered. Desmoyokin was localized to the non-desmosomal and non-hemidesmosomal epidermal keratinocyte cell surface as a plasma membrane-associated protein, and might play a role in cell adhesion that is not directly associated with desmosomes or hemidesmosomes.

[A patient with a relapse of myasthenia gravis after a 13-year remission following successful treatment by mediastinal irradiation and corticosteroid therapy]

We report a patient with myasthenia gravis who experienced a relapse 13 years after apparently successful treatment by mediastinal irradiation and corticosteroid therapy. A 20-year-old male was admitted to Shinshu University Hospital with a chief complain double vision and drooping eyelids. These symptoms had appeared 2 months prior to admission. They tended to be more severe late in the day, and varied from day to day. Prior to this admission the patient had been healthy for the 13 years since undergoing 45-Gy mediastinal irradiation and corticosteroid therapy. MRI and CT studies revealed no thymic hyperplasia. Total thymectomy was performed, and his myasthenic symptoms, including the opthalmoplegia, improved. Histological examination of the resected thymus revealed an active thymus with germinal centers. Immunohistological studies showed an abundance of intracellular adhesion molecule-1 (ICAM-1) in the germinal centers and thymic medullary epithelium, and the presence of lymphoid function-associated antigen-1 (LFA-1) in thymic lymphocytes. ICAM-1 and LFA-1 are ligand of adhesion molecules which interact with each other and play an important role in antigen presentation. Acetylcholine receptor (ACh-R) antigen is known to be present in the thymus. The presence of both ICAM-1 and LFA-1 in the active thymus in this patient suggests that these adhesion molecules may have a role in ACh-R antigen presentation, causing myasthenia. These findings suggest that patients with myasthenia gravis who do not undergo total thymectomy have a risk of recurrence, even after long-term remission.

Methamphetamine-induced dopaminergic hyperactivity is not accompanied with increase in tyrosine hydroxylase mRNA of the rat midbrain

Tyrosine hydroxylase (TH) mRNA was measured in the midbrain of rats treated repeatedly with methamphetamine (MAP). Male Sprague-Dawley rats were daily injected with MAP (5 mg/kg, i.p., once daily) or saline for 14 days. Progressive augmentation was observed in MAP-induced stereotyped behaviors. After one week of abstinence, the rats were decapitated and the brains were prepared for either in situ hybridization using non-radioactive cRNA probes or Northern blot analysis using 32P-labeled cDNA probes. In situ hybridization showed that the signals of TH mRNA were localized to the dopaminergic perikarya in the midbrain and were reduced in MAP-treated animals compared to the controls. Northern blot analysis revealed that the level of TH mRNA in the midbrain of MAP-treated rats was decreased by 37% compared to the controls, which was close to the statistical significance (P = 0.053). These results indicate that the dopaminergic hyperactivity caused by repeated MAP treatment is not associated with enhanced transcription of the TH gene.

Developmental brain changes investigated with proton magnetic resonance spectroscopy

Volume-selective proton magnetic resonance spectroscopy (1H-MRS) of the brain was performed with a 1.5 Tesla magnet in 47 healthy children and in six healthy adults. Peaks of N-acetylaspartate (NAA), choline (Cho) and creatine (Cr) were observed in all cases, but a lactate peak was not observed. In the right parietal region. 1H-MRS revealed increases in the rations of NAAJCho and NAA/Cr and a decrease in Cho/Cr with advancing age. The most rapid changes were noted between one and three years of age. 1H-MRS of the right frontal region also was performed in 21 cases (20 children and one adult). In the right frontal region, there was an increase in the ratio of NAA/Cho and a decrease in Cho/Cr with advancing age, while a developmental change was not observed in the ratio of NAA/Cr. The ratios of both NAA/Cho and NAA/Cr were lower in the right frontal region than in the right parietal region. These results show that developmental changes and regional variation of metabolites are observed in 1H-MRS of the brain, and need to be considered in its application.

Ectodermal dysplasia syndrome in siblings with true keloids, stenosis of the esophagus after operations for congenital achalasia and renovascular hypertension due to stenosis of renal artery

Ectodermal dysplasia syndrome (EDS) is a rare hereditary disease, with symptoms brought about by dysplasia of ectodermal tissue (such as skin, teeth, nails, and hair). This report details the cases of two siblings (41 and 43 year old sisters) with autosomal recessive and hydrotic EDS complicated by esophageal achalasia, postoperative stenosis of esophagus, true keloids, renovascular hypertension, incomplete malrotation of the bowel, and demyelination of the brain.

Proton magnetic resonance spectroscopy of brain in congenital myotonic dystrophy

Volume selective proton magnetic resonance spectroscopy of brain was performed on a 1.5 T magnet in 5 patients with congenital muscular dystrophy and compared to the results in 46 healthy children and 1 healthy adult. Peaks of N-acetyl aspartate, choline, and creatine but not lactate, were observed in both groups on proton magnetic resonance spectroscopy. Spectroscopy of controls revealed an increase with advancing age in the ratio of N-acetyl aspartate/choline and N-acetyl aspartate/creatine and a decrease in the choline/creatine ratio. In patients with congenital myotonic dystrophy, the N-acetyl aspartate/choline ratio did not increase with advancing age, but the N-acetyl aspartate/creatine ratio did. The choline/creatine ratio decreased with advancing age, which matched the results of controls. At any age older than 4 years, the N-acetyl aspartate/choline and N-acetyl aspartate/creatine ratios were lower in patients with congenital myotonic dystrophy than in controls. The choline/creatine ratio did not differ between congenital myotonic dystrophy and controls. These results suggest that in patients with congenital myotonic dystrophy N-acetyl aspartate decreases and there exists a developmental disorder of neurons in brain.

Granulocytapheresis as a possible cancer treatment

We assessed the effect of granulocyte apheresis in patients exhibiting increased granulocyte-to-lymphocyte ratio in order to overcome granulocytosis occurring in the terminal stages of malignancies. 17 patients with post-operative recurrent metastatic tumors including 6 gastric, 3 colonic, 2 rectal, 1 esophageal and 5 breast cancers were selected. The granulocytapheresis was performed by extracorporeal vein-to-vein circulation equipped with an apheresis column filled with cellulose acetate beads. Each week the patients underwent one or two sessions of treatment that lasted 30 to 50 minutes per session at a flow rate of 30 to 50 ml/min. 15 sessions formed 1 therapeutic cycle. The effect of granulocytapheresis resulted in partial response (PR) in 4 cases, no change (NC) in 7 cases and partial disease (PD) in 6 cases. The performance status showed 30% remission. None of the patients exhibited significant side effects. Since the treatment demonstrated anti-tumor effects, granulocytapheresis may be applied during combined cancer treatments.

A quantitative method for cDNA-directed expression in cultured mammalian cells

A simple technique of quantitative cDNA-directed expression was devised by using a vaccinia virus system. The technique was applied to the cDNA expression of peroxisomal acyl-coenzyme A oxidase (AOX) and microsomal cytochromes P450 1A2, 2E1, and 3A4. Quantitative cDNA expression of all four enzymes tested was successfully achieved. This represents important progress for establishing the relationship between the amount of enzyme and its function in cells. The vaccinia virus system was also used to express AOX protein in specific cellular regions.

Dynamic analysis of intraarticular pressure in the glenohumeral joint

Dynamic analysis of intraarticular pressure was performed in 180 glenohumeral joints. The intraarticular pressure demonstrated characteristic changes during shoulder movement. In the healthy group minimum pressure was measured at 40 degrees of elevation in the scapular plane. In patients with contractures the pressure increased in the early phase of elevation and persisted. Pressure changes of the group with incomplete tears of the rotator cuff resembled those of the healthy group, whereas those in the massive tear group showed only slight pressure changes. When patients with rotator cuff tears had no limitation of arm elevation, pressure changes close to the normal pattern were found. However, when active elevation was markedly limited, no significant pressure changes were noted in some cases. In unstable shoulders the rate of pressure increase was slower, and the range of pressure changes was more limited than that in the healthy group. It is speculated that changes in intraarticular pressure reflect the intraarticular volume. Measurement of the intraarticular pressure may be clinically useful in functional assessment.

Effects of volume loading on pulmonary venous flow pattern in dogs with normal left ventricular function

The effects of altered loading conditions on the pattern of pulmonary venous flow are poorly understood. The authors investigated such effects, therefore, by using volume loading in 6 open-chest dogs. The pulmonary venous flow volume rate curve was obtained with a transit-time ultrasonic flowmeter at a fixed heart rate. Measurements were performed in the control and several states during the intravenous infusion of dextran. The influences of volume loading on hemodynamic and pulmonary venous flow variables were compared between the control state and three interventional states in which mean left atrial pressure was approximately 1, 2, and 3 mm Hg above the control value. The systolic flow volume (SI), which corresponds to left atrial reservoir volume, significantly increased, but the early diastolic flow volume (DI), which corresponds to left atrial conduit volume, did not show significant change with volume loading. The flow volume during left atrial contraction significantly increased with volume loading. The flow volume during one cardiac cycle (PVF) significantly increased with volume loading. Approximately 73% of increased PVF was distributed to the systolic flow. The rest was distributed to the early diastolic flow (14%) and to the flow during left atrial contraction (12%). The change in the ratio of SI/DI significantly and positively correlated with the change in mean left atrial pressure (r = 0.87, P < 0.001). These findings indicate that increased pulmonary venous flow induced by volume loading in dogs with normal left ventricular function is mainly distributed to the left atrial reservoir volume.

Differential (Ha-, K- and N-) ras p21 expression in benign and malignant human thyroid tumors: an immunohistochemical study

An immunohistochemical study of 24 thyroid carcinomas, 10 thyroid adenomas and 10 normal thyroids was performed using monoclonal antibodies directed against each of the three members of ras p21s; Ha-, K- and N-ras p21. Normal thyroids showed a negative staining for all of the three ras p21s. The expressional levels of the three ras p21s were various in each benign and malignant thyroid tumor, but a higher expression of Ha- and N-ras p21 and a lower or negative expression of K-ras p21 was a common finding in thyroid tumors of all histologic categories. There were no correlations between the expressional levels of ras p21s and the histologic subtypes, tumor size or lymph node status in the thyroid carcinomas.

[A case of adult Wilms' tumor with vena caval involvement]

The patient was a 35-year-old female with the chief complaint of macrohematuria. Computerized tomographic (CT) scan, ultrasonography and magnetic resonance imaging (MRI) revealed the presence of a large and inhomogeneous mass in the left kidney, and a tumor thrombus growing in the inferior vena cava. Angiography also showed a hypervascular tumor in the left kidney. The chest X-ray and CT scan demonstrated multiple metastatic lesions in the bilateral lungs. Radical nephrectomy and thrombectomy was performed under the diagnosis of left renal tumor with its invasion of inferior vena cava. Pathological findings revealed that this tumor was nephroblastoma, and its type was clear cell sarcoma of the kidney (CCSK). The patient received chemotherapy according to National Wilms' Tumor Study (NWTS) IV chemotherapeutic drug regimen. In general, CCSK is known to have poor prognosis. However, doxorubicin has been reported to have a relatively good antitumor effect for CCSK. However, in this case, the evaluation after the first course of chemotherapy was progressive disease, because some new lesions appeared, although most old pulmonary metastatic lesions were reduced.

[Proton MR spectroscopy of the brain in patients with congenital myotonic dystrophy]

Volume selective proton MR spectroscopy (1H-MRS) of the brain was performed on a 1.5T magnet in five patients with congenital muscular dystrophy (CMyD), 46 healthy children, and one healthy adult. Peaks of N-acetylaspartate (NAA), choline (Cho) and creatine (Cr) were observed in both patients and control groups on 1H-MRS, but lactate was not observed. 1H-MRS revealed an increase in the ratio of NAA/Cho and NAA/Cr, and a decrease in Cho/Cr ratio with age in control subjects. In patients with CMyD, the values of NAA/Cho ratio did not increase with age. The values of NAA/Cr ratio decreased with age. The values of Cho/Cr ratio decreased with age in both patient and control groups. At age more than 4 years, the values of NAA/Cho and NAA/Cr ratios were lower in patients with CMyD than in controls. The values of Cho/Cr ratio did not differ between CMyD and controls. These results suggest that in patients with CMyD, there is an NAA decrease and a developmental disorder of neurons in the brain.

Characterization of paraneoplastic pemphigus autoantigens by immunoblot analysis

We investigated the antigen molecules for six clinically typical cases of paraneoplastic pemphigus (PNP) using immunofluorescence, immunoprecipitation, and immunoblotting. All the PNP sera showed a clear reactivity with transitional epithelia of rat urinary bladder and immunoprecipitated the 250-kD, 230-kD, 210-kD, 190-kD, and 170-kD proteins in various combinations, confirming the diagnosis of PNP. Immunoblot analysis demonstrated slightly different reactivity from that of immunoprecipitation. With immunoblotting of normal human epidermal extract, bovine desmosome preparation, and extract of cultured squamous cell carcinoma cells, all the PNP sera reacted with a characteristic doublet of the 210-kD and 190-kD proteins. However, immunoblotting detected the 250-kD desmoplakin I and the 230-kD bullous pemphigoid antigen less frequently and did not detect the 170-kD protein. Further immunoblot studies indicated that the 210-kD protein is different from desmoplakin II and that the 190-kD protein is most frequently detected by PNP sera. Two of the six PNP sera specifically reacted with the extracellular domain of recombinant pemphigus vulgaris antigen protein, indicating that pemphigus vulgaris antigen may be involved in PNP. In future studies to unravel the complex mechanisms of the PNP antigens, the immunoblot technique may be a useful tool.

A new type of human calcitonin receptor isoform generated by alternative splicing

There are three isoforms of calcitonin receptors (CTRs). The first type (type 1) has 479 amino acids in rat and 482 amino acids in porcine. The second type (type 2) has a 39 amino acid insertion in the second extracellular domain. The third type (type 3) has a 16 amino acid insertion in the first intracellular domain. The CTR which has been isolated from a human ovarian carcinoma cell line belongs to type 3. Using RT-PCR with primers whose sequences correspond to the human CTR cDNA, we analyzed the expression of the CTR transcripts in seven human tumor cell lines and surgical specimens. The CTR m-RNA were found in all samples. Transcripts which were 48bp shorter than that of the type 3 human CTR were detected, but not transcripts of type 2 and type 3. Since the structure of this CTR is same as that of the type 1 rat and porcine CTRs, we termed it the human type 1 CTR. PCR studies using human genomic DNA as a template revealed that the 48bp sequence constitutes an exon. These results indicate that the type 1 and the type 3 human CTRs are generated by alternative splicing and a majority of human CTR transcripts is type 1.

[Immunohistochemical study of the endomyocardial biopsy of systemic lupus erythematosus]

The mechanisms of cardiac involvement in systemic lupus erythematosus (SLE) were studied using immunohistochemical staining of endomyocardial biopsy specimens from 14 patients with SLE and normal coronary arteriograms. All 14 specimens showed mild interstitial edema, 11 showed mild cardiac fibrosis, and another two cases showed moderate cardiac fibrosis with myocardial derangements. Four specimens showed moderate cell infiltration in the interstitium. Area of fibrosis, diameter of myocardium and area of interstitial edema were increased in the SLE patients compared to the control cases. Immunofluorescence showed IgG and fibrinogen deposition in the membrane of cardiac myocytes and in the interstitium. Immunohistochemistry found no B lymphocytes in any of the seven SLE cases. T lymphocytes were observed in all seven SLE cases, and OKT 8 lymphocytes were increased significantly in the interstitial tissue as compared with OKT 4 lymphocytes. At endomyocardial biopsy, all 14 patients were receiving corticosteroid therapy and had low activity disease. The results suggest that cardiac tissue damage was associated with immunological abnormalities and might progress silently under conditions in which the disease activity was suppressed by corticosteroid therapy.