Spatiotemporal development of the neuronal accumulation of amyloid precursor protein and the amyloid plaque formation in the brain of 3xTg-AD mice

The amyloid plaque is a hallmark of Alzheimer's disease. The accumulation of the amyloid precursor protein (APP) in the neuronal structure is assumed to lead to amyloid plaque formation through the excessive production of β-amyloid protein. To study the relationship between the neuronal accumulation of APP and amyloid plaque formation, we histologically analyzed their development in the different brain regions in 3xTg-AD mice, which express Swedish mutated APP (APPSWE) in the neurons. Observation throughout the brain revealed APPSWE-positive somata in the broad regions. Quantitative model analysis showed that the somatic accumulation of APPSWE developed firstly in the hippocampus from a very early age (<1 month) and proceeded slower in the isocortex. In line with this, the hippocampus was the first region to form amyloid plaques at the age of 9-12 months, while amyloid plaques were rarely observed in the isocortex. Females had more APPSWE-positive somata and plaques than males. Furthermore, amyloid plaques were observed in the lateral septum and pontine grey, which did not contain APPSWE-positive somata but only the APPSWE-positive fibers. These results suggested that neuronal accumulation of APPSWE, both in somatodendritic and axonal domains, is closely related to the formation of amyloid plaques.

Exploring the Limits of Bottom-Up Gold Filling to Fabricate Diffraction Gratings

Gold deposition on rotating disk electrodes, Bi3+ adsorption on planar Au films and superconformal Au filling of trenches up to 45 μm deep are examined in Bi3+-containing Na3Au(SO3)2 electrolytes with pH between 9.5 and 11.5. Higher pH is found to increase the potential-dependent rate of Bi3+ adsorption on planar Au surfaces, shortening the incubation period that precedes active Au deposition on planar surfaces and bottom-up filling in patterned features. Decreased contact angles between the Au seeded sidewalls and bottom-up growth front also suggest improved wetting. The bottom-up filling dynamic in trenches is, however, lost at pH 11.5. The impact of Au concentration, 80 mmol/L versus 160 mmol/L Na3Au(SO3)2, on bottom-up filling is examined in trenches up to ≈ 210 μm deep with aspect ratio of depth/width ≈ 30. The microstructures of void-free, bottom-up filled trench arrays used as X-ray diffraction gratings are characterized by scanning electron microscopy (SEM) and Electron Backscatter Diffraction (EBSD), revealing marked spatial variation of the grain size and orientation within the filled features.

Optogenetics Identification of a Neuronal Type with a Glass Optrode in Awake Mice

It is a major concern in neuroscience how different types of neurons work in neural circuits. Recent advances in optogenetics have enabled the identification of the neuronal type in in vivo electrophysiological experiments in broad brain regions. In optogenetics experiments, it is critical to deliver the light to the recording site. However, it is often hard to deliver the stimulation light to the deep brain regions from the brain's surface. Especially, it is difficult for the stimulation light to reach the deep brain regions when the optical transparency of the brain surface is low, as is often the case with recordings from awake animals. Here, we describe a method to record spike responses to the light from an awake mouse using a custom-made glass optrode. In this method, the light is delivered through the recording glass electrode so that it is possible to reliably stimulate the recorded neuron with light in the deep brain regions. This custom-made optrode system consists of accessible and inexpensive materials and is easy to assemble.

ToF-SIMS Depth Profiling of Organic Films: A Comparison between Single Beam and Dual-beam Analysis

In dual-beam depth profiling, a high energy analysis beam and a lower energy etching beam are operated in series. Although the fluence of the analysis beam is usually kept well below the static SIMS limit, complete removal of the damage induced by the high energy analysis beam while maintaining a good depth resolution is difficult. In this study a plasma polymerized tetraglyme film is used as the model organic system and the dimensionless parameter R, (analysis beam fluence)/(total ion fluence), is introduced to quantify the degree of sample damage induced as a function of the analysis beam fluence. It was observed for a constant C(60) (+) etching beam fluence, increasing the analysis fluence (and consequently increasing the R parameter) increased in the amount of damage accumulated in the sample. For Bi(n) (+) (n = 1 and 3) and C(60) (+) depth profiling, minimal damage accumulation was observed up to R = 0.03, with a best depth resolution of 8 nm. In general, an increase in the Bi(n) (+) analysis fluence above this value resulted in a decrease in the molecular signals of the steady state region of the depth profile and a degradation of the depth resolution at the polymer/substrate interface.

Distribution characteristics of acid-dissolved trace metals of suspended particulate matter (SPM) in Kurashiki, Japan

This study was undertaken to examine the distribution characteristics of such trace metals in fine particulate (especially with diameters of less than 2.1 microns). The acid-dissolved metals in suspended particulate matter (0.1-9.0 microns) were examined with consideration given to particle size over a 2-year period. It became clear the metals of artificial origin such as Pb, V, Cd, Ni, Cr exist in fine particulates (0.1 or more 2.0 microns), whereas metals of natural origin, such as Ti, Mn, Mg, and Sr primarily exist in coarse particles (2.1-9.0 microns) in Kurashiki City, near the Mizushima Industrial Area in Japan.

A milestone for normal development of the infantile brain detected by functional MRI

OBJECTIVE

To investigate the relationship between cerebral cortical function and white matter myelination in the visual pathway in the evaluation of normal brain development.

METHODS

The authors performed quantitative analysis of white matter myelination detected with conventional T1-weighted spin echo (SE) MRI and brain functional MRI (fMRI) using echoplanar imaging with photic stimulation in 27 neurologically normal infants (age range, 0 to 22 weeks).

RESULTS

An age-dependent gradual increase in signal intensity was observed in optic radiation on the T1-weighted SE images, indicating progression of white matter myelination. A rapid age-dependent reverse in signal response was observed on fMRI. Infants older than 8 weeks showed a stimulus-induced signal decrease in the visual cortex, whereas infants younger than 7 weeks showed a signal increase.

CONCLUSIONS

A rapid inversion of response revealed by fMRI with photic stimulation in infants suggests a change in oxygen consumption during neuronal activation, which is related to rapid synapse formation and accompanying increased metabolism. fMRI can detect dynamic metabolic changes during brain maturation, which is a different developmental process from white matter myelination. The metabolic changes detected by fMRI provide a milestone for the evaluation of normal brain development.

Toxicity of organic and inorganic mercury to Saccharomyces cerevisiae

In this study the effect if six different forms of mercury on the growth of the yeast Saccharomyces cerevisiae is presented. Five kinds of strains of S. cerevisiae were used. They were a wild type, a mercury-resistant type, and three mutants: mutation repair-deficient mutant, excision repair-deficient mutant, and recombination repair-deficient mutant. In terms of EC50 toward the wild-type strain, the toxicity order for the inorganic forms was Hg(NO3)2>HgSO4>HgCl2. Monovalent nitrate mercury Hg(NO3)2 was more toxic than bivalent Hg(NO3)2. The toxicity of organic mercury CH3HgCl on cell growth was two orders of magnitude higher than that of inorganic HgCl2. Between the two organic forms, CH3HgCl was more toxic than CH3HgOH. The survival rate in the presence of a certain concentration of CH3HgCl was about one-hundredth of the survival in presence of the same concentration of HgCl2. On the other hand, the concentration of CH3HgCl in the cell was about 170 times that of HgCl2. The addition of chelating agents, EDTA and methyl-penicillamine, to the medium did not reduce the toxicity of mercury. Among the three mutants tested, the one deficient in recombination repair systems was the most sensitive to mercury.

Assessment of hepatic portal perfusion using T2 measurements of Gd-DTPA

Recently, perfusion imaging has been of increasing interest in MRI. We applied this method for semiquantitative evaluation of hepatic parenchymal portal blood flow in patients with diffuse liver damage. Twenty patients with diffuse hepatic damage were divided according to the Child's Classification and studied. Gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) was administered into the superior mesenteric artery (SMA), and a dynamic series of T2*-weighted fast low angle shot (FLASH) images was obtained. We evaluated relative regional portal blood volume (rrPBV), mean transit time (MTT), and relative regional portal blood flow (rrPBF). The relationship between the rrPBV, rrPBF, and plasma indocyanine green retention rate test at 15 minutes (ICGR15 was also evaluated in 12 patients. Both rrPBF and rrPBV are significantly decreased in Child B & C patients compared with Child A patients. On the other hand, the MTT is significantly prolonged in Child B & C patients compared with Child A patients. Significant correlations were also noted between rrPBV and ICGR15 and between rrPBF and ICGR15. By means of selective catheterization into the SMA, we were able to estimate rrPBV, rrPBF, and MTT. This method may play a clinical role for assessment of regional portal perfusion in various diseases with diffuse liver damage.

[Prognosis of amyotrophic lateral sclerosis--clinical analysis]

We report the results of a study on the long-term outcome of amyotrophic lateral sclerosis (ALS). The clinical subjects were 81 ALS patients, 75 of whom required assisted ventilation, and 57 of whom have died. We found that the following factors were associated with a longer clinical course: (1) younger onset: (2) female sex: (3) left-sided predominance of amyotrophy: (4) slower development of bulbar symptoms.

Cytosolic localization of beta 3-subunit of heterotrimeric GTP binding protein in rat hearts

The expression of three different subtypes of GTP binding protein beta-subunits (beta 1, beta 2 and beta 3) was examined in rat hearts at both mRNA and protein levels. Among three subtypes, beta 3 mRNA was more abundant in ventricles while beta 1 and beta 2 mRNAs were expressed ubiquitously among ventricles, atria and aortas. The immunodetectable beta 1- and beta 3-proteins were predominantly found in the cytosolic fraction of rat ventricles. In this study, we demonstrate ventricle-specific expression of beta 3-subunit and localization of G protein beta 3-subunit in the cytosol of rat hearts. This unusual cytosolic localization of G protein beta 3-subunit might indicate subtype-specific function of G protein beta (gamma)-subunits in rat hearts.

Peripheral neuroectodermal tumor presenting pleural effusion

Pleural effusion is a common finding of peripheral neuroectodermal tumor (PNET) of the chest wall (Askin's tumor), but little is known about the characteristics. A case of Askin's tumor with pleural effusion is reported. Repeated cytologies were negative for malignancy, but levels of lactic dehydrogenase (LDH) and neuron-specific enolase (NSE) in the pleural effusion were increased. Surgical biopsy was performed and immunohistochemical study of the tumor revealed the diagnosis.

[Specific expression and distribution of the isoforms of GTP binding protein beta subunits in hearts]

A growing body of evidence now supports the idea that free beta gamma subunits of GTP binding proteins (G proteins) can themselves interact functionally with effector proteins. Recent results suggest that beta subunits might be playing a key role to specify the receptor-effector coupling in various transmembrane signaling systems. The purpose of this study is to examine the expression level and distribution of G protein beta subunits in rat hearts. Brain and ventricle of WKY rats were used to examined the expression of three different isoforms of beta subunits in mRNA and protein level by means of Northern blot and Western blot analysis, respectively. beta 3 mRNA was expressed significantly more in ventricles than in brains. This result was supported by Western blot analysis showing that beta 3 was expressed more in ventricles. For all three isoforms (beta 1 beta 2 and beta 3), the majority of beta subunits expressed in rat hearts were detected in cytosolic fractions. An ultrafiltration and subsequent Western blot analysis revealed that the beta subunits in ventricular cytosolic fractions had molecular mass greater than 100,000 dalton. In this study, tissue-specific expression of beta subunit isoforms was revealed in rat hearts.

[A case of long-standing isolated traumatic tricuspid regurgitation with remarkably dilated right cardiac chambers and pancytopenia]

We report a rare case of tricuspid regurgitation due to nonpenetrating chest trauma 33 years previously. A 79-year-old man suffered a blunt trauma due to a piece of wood at work in 1958. He suffered multiple rib fractures on the right side and was admitted. Since then, he began having shortness of breath on exertion and was treated with medication. The patient was transferred to the Division of Cardiology, Hakodate National Hospital in 1984. A chest x-ray film revealed a marked cardiomegaly. Cardiac catheterization showed severe tricuspid regurgitation. Hepatomegaly and pancytopenia was observed. He was readmitted because of general fatigue in July 1991. Two-dimensional echocardiography demonstrated systolic excursion of septal and posterior tricuspid leaflets with ruptured chordae tendineae into the right atrium, and a remarkably enlarged right ventricule, right atrium and vena cava interior. Cardiac catheterization was performed. The right atrial pressure-wave form resembled the right ventricular pressure recording (ventricularization of the atrial pressure). Right ventricular cineangiography revealed severe tricuspid regurgitation, grade 4. Laboratory data showed pancytopenia. Thrombocytopenia progressed (3 x 10(4)/mm3), and a hemorrhagic tendency developed. The liver edge was palpable 4 finger breadths below the right costal margin. Pancytopenia due to congestive hepatomegaly and hypersplenism would have complicated this case.

Phosphatidylinositol metabolism in hypertrophic rat heart

The accumulation of inositol 1,4,5-trisphosphate (IP3) after hormonal stimulation has a physiological role, possibly by alteration of Ca2+ levels in cardiac myocyte. However, this accumulation has not been studied under pathophysiological conditions. In this report, we examine phosphatidylinositol metabolism during cellular response to norepinephrine in pressure-overloaded hypertrophic rat heart. After stimulation with norepinephrine, the accumulations of IP3 and diacylglyceride significantly increased in isolated myocytes from stroke-prone spontaneously hypertensive rat (SHRSP) heart, indicating phosphatidylinositol-specific phospholipase C activity increased in SHRSP heart cells. Protein kinase C activity was also enhanced in SHRSP, with a marked increase in particulate activity. We determined the intracellular calcium concentration and found it to be higher in SHRSP than in Wistar-Kyoto (WKY) rats at 30-40 weeks of age. Ca2+ influx was also elevated in SHRSP stimulated by norepinephrine. In SHRSP heart, cytosolic Ca2+ concentration may rise quickly in response to some stimuli, such as alpha 1-adrenergic stimulation, which is shown to be one of the pathways that increases cytosolic Ca2+ levels in hypertrophied rat heart. These data suggest that a part of the phosphatidylinositol-turnover pathway, such as the phosphatidylinositol 4,5-bisphosphate-IP3-Ca2+ pathway or the diacylglyceride-protein kinase C pathway, may play an important role in the development of hypertrophy in SHRSP heart.

[Anti-bacterial zeolite balloon catheter and its potential for urinary tract infection control]

We present here a production of anti-bacterial zeolite balloon catheter and investigated its potential for controlling urinary tract infection. This anti-bacterial balloon catheter showed a bactericidal effect against Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli in vitro studies. The antibacterial effects were correlated with the concentration of anti-bacterial zeolite and size of catheter. We tried this catheter for 11 various urological patients who needed a long-term indwelling of a balloon catheter for lower urinary tract obstruction and neurogenic bladder. All patients were already indwelled silicon balloon catheter for 3 to 6 months and suffered with complicated urinary tract infection. Nine patients who had this anti-bacterial zeolite balloon catheter indwelled for 3 to 7 months and exchanged every 2 to 4 weeks, and no patient was taking antibiotics during this trial. Two patients (22.2%) showed good results by the urinary tract infection (UTI) criteria and 5 patients (55.4%) showed good effects by doctor's judgment. This anti-bacterial zeolite balloon catheter might be useful for patients who need long-term balloon catheter indwelling.

CONGENITAL PELVIC ARTERIOVENOUS FISTULA IN A MALE A Case Report

A congenital arteriovenous fistula (AV fistula) in the true pelvis is extremely rare, especially in males. We present a case of this disease with pollakiuria and intrarectal discomfort. Diagnosis was made by computed tomography and magnetic resonance imaging and confirmed by cine angiography. Because the AV fistula involved the bladder, prostate and rectum, ligation of the main feeding arteries was performed. He also had benign prostatic hypertrophy and was treated by conservative therapy because of a high risk of massive bleeding in surgical treatment.

[Incidental renal cell carcinoma]

We reviewed the cases of incidental renal cell carcinoma that had been treated at the Kitasato University Hospital between July, 1971 and December, 1989. Forty one of the 170 (24.1%) cases were found without any direct signs of renal cell carcinoma. The patients were between 30 and 78 years old (mean 55.0 years) and consisted of 29 males and 12 females. Fifteen cases were detected at the general health check-up and the remaining 26 during the postoperative follow-up for other malignant tumors or other diseases. Twenty three cases were identified by ultrasonography followed by computed tomography (CT) and excretory pyelography in 4 cases each. Especially, the number of patients incidentally found by ultrasonography had increased in the recent 8 years. Urinalysis did not show any microhematuria in 31 of the 37 cases (83.7%), and no tumor mass could be detected by excretory pyelography in 3 cases. We believe that ultrasonography may be valuable as a screening modality for early detection of renal cell carcinoma and should be used as a screening method at the routine health check-up.

[Leiomyosarcoma of the esophagus associated with pulmonary edema by the compression of the left atrium]

Leiomyosarcoma of the esophagus is a rare neoplasm. We reported a very rare case of esophageal leiomyosarcoma associated with pulmonary edema by the compression of the left atrium. A 67-year-old man was admitted with a 3-month history of chest pain, exertional dyspnea and dysphagia. Chest X-ray computed tomography showed posterior mediastinal tumor. Esophageogastroscopy and fiberoptic bronchofiberscopy showed no direct invasion of the tumor. By echocardiography, the left atrium was found to be compressed by the tumor and pulmonary hypertension (58/25 mmHg) and increased pulmonary wedge pressure (25 mmHg) was present. Open biopsy specimen demonstrated elongated cells suggestive of sarcoma. At autopsy, the tumor was confirmed to be leiomyosarcoma and to be originated from the lower esophagus.

[A case of pulmonary aspergillosis presenting pulmonary bulla and eosinophilic pneumonia]

A rare case of a 25-year-old man with pulmonary aspergillosis is reported. Pulmonary bulla and eosinophilic pneumonia in the right upper lobe were diagnosed by chest roentgenogram and transbronchial lung biopsy. Because the patient developed infective bullae during steroid therapy, we performed transcutaneous thoracic drainage and right upper lobectomy. The resected lung tissue contained numerous hyphae of Aspergillus. Around the hyphae of Aspergillus, granulomatous reaction and eosinophilic infiltration were observed. Antibodies against Aspergillus were detected in the serum of the patient. The number of peripheral blood eosinophils decreased after right upper lobectomy. These findings suggest that pulmonary bullae and eosinophilic pneumonia may be a rare manifestation of pulmonary aspergillosis.

Unresponsiveness to L-DOPA in parkinsonian patients: a study of homovanillic acid concentration in the cerebrospinal fluid

In this study, concentrations of homovanillic acid (HVA), a principal metabolite of dopamine (DA), in the cerebrospinal fluid (CSF) were measured in 17 patients with Parkinson's disease (PD) who had been effectively treated with L-DOPA and in 8 patients clinically diagnosed as having striatonigral degeneration (SND) and for whom treatment with L-DOPA had proved ineffective. L-DOPA administration, consisting of a daily dosage of 600 mg plus 150 mg aromatic L-amino acid decarboxylase inhibitor was continued in all cases for at least 3 months. In the PD group, the HVA value was 511.6 +/- 196.5 pmol/ml and in the SND group, 144.9 +/- 83.4 pmol/ml. This remarkably low value for the SND group suggests that there may exist severe disorders in the uptake and decarboxylation of exogenous L-DOPA.

Sex differences in gallbladder bile acid composition and hepatic steroid 12 alpha-hydroxylase activity in hamsters

The gallbladder bile acid composition and the activity of the hepatic steroid 12 alpha-hydroxylase were determined in male and female hamsters. Cholic acid, chenodeoxycholic acid, and deoxycholic acid were the major bile acids in both sexes; in addition, 7-ketodeoxycholic acid and lithocholic acid were present. A sex-linked difference in the ratio of cholic acid (plus its metabolites) to chenodeoxycholic acid (plus its metabolite) was observed. The ratio was 1.93 +/- 0.39 in males and 2.74 +/- 0.54 in females. Another sex-linked difference was found in the activity of the 12 alpha-hydroxylase. The extent of the 12 alpha-hydroxylation of 7 alpha-hydroxycholest-4-en-3-one to yield 7 alpha, 12 alpha-dihydroxycholest-4-en-3-one was about two times greater in the microsomal suspension obtained from the liver of female hamsters than in that of male hamsters. A positive correlation between the 12 alpha-hydroxylase activity and the ratio of cholic acid/chenodeoxycholic acid was also observed. These results strongly support the proposal that the activity of the 12 alpha-hydroxylase is the major factor in determining the relative proportion of cholic acid and chenodeoxycholic acid formed from cholesterol in the liver.

Effect of feeding cholesterol and sitosterol on hepatic steroid 12 alpha-hydroxylase activity in female hamsters

The effects of dietary cholesterol and sitosterol on the activity of the hepatic steroid 12 alpha-hydroxylase, gallbladder bile acid composition, and serum and liver cholesterol concentrations were studied in female hamsters. The 12 alpha-hydroxylase activity was inhibited by 63% in cholesterol-fed animals and by 30% in sitosterol-fed animals. Cholesterol feeding increased percentages of chenodeoxycholic and lithocholic acids in gallbladder bile with reciprocal decrease of cholic acid, while sitosterol feeding had no significant effect on bile acid composition. Cholesterol feeding increased levels of serum and liver cholesterol, on the contrary, sitosterol decreased both concentrations. A positive correlation between the 12 alpha-hydroxylase activity and the ratio of cholic acid plus its metabolites to chenodeoxycholic acid plus its metabolite was also observed. These results support the proposal that steroid 12 alpha-hydroxylase is a major factor in determining the relative proportion of cholic acid and chenodeoxycholic acid synthesized in the liver and indicate that cholesterol feeding increased percentage of chenodeoxycholic acid by inhibiting the activity of steroid 12 alpha-hydroxylase.

[Clinical evaluation of cardiac function test using scintiview (author's transl)]

Cardiac function was studied with Scintiview in 107 cases, 24 normal and 83 affected cases, and the following results were obtained. 1. Better data were obtained with converging collimeter than with parallel collimeter in cardiac study. (2) Red blood cells were sufficiently labeled with 99mTc using stannous chloride as reductant, and it was proven to be applicable to measurement of circulation blood volume. (3) Pulmonary circulation time and the systemic circulation time calculated from time activity curve, greater than 9.0 seconds and greater than 25 seconds, respectively, were considered abnormal prolongation. (4) Cardiac output index (cardiac output/circulation blood volume), less than 1.10 was considered decreased cardiac output. (5) Stroke volume index ((stroke volume/circulation blood volume)x 100, less than 1.70 was considered decreased stroke volume. (6) Ejection fraction, less than 60% was considered decreased left ventricular wall motion. (7) Cardiac function index (cardiac output index X ejection fraction), less than 80 was considered decreased cardiac performance.

[TSH responses to TRH in the addisonians (author's transl)]

After the administration of TRH the hyperresponse of TSH was observed in the non-treated addisonians and the normal response in the treated addisonians. These reulsts are inverted to those found in the patients of hyperadrenocorticism or treated with corticoid. This hyperresponse of TSH to TRH is due to the lack of corticoid and makes us suppose that the corticoid controls the TRH-TSH system as well as the CRF-ACTH system.

Onset and progression of diabetic glomerulosclerosis; a prospective study based on serial renal biopsies

Clinical factors related to the development and progression of renal lesions were studied in twenty-three diabetics by the use of serial renal biopsies or autopsy. The results were as follows: Most of the juvenile and intermediate type diabetics were poorly controlled, with the glomerular lesion progressing rather rapidly. In contrast, many cases of the adult type were able to be maintained under good control and the renal lesion neither developed nor progressed. Two of the adult type diabetics with poor control showed slowly and slightly progressing renal lesions. The progression of glomerular lesions was significantly related to the control of blood glucose, type of diabetes, age at onset, type of treatment, and degree of obesity, but not to the duration of diabetes or the length of the follow-up period. There was a significant correlation between the type of diabetes and the control of blood glucose over the years. Arteriolar lesions developed concurrently with the progression of the glomerular lesion. Retinopathy also had a tendency to develop in proportion to the progress of glomerular lesions although it was not statistically significant. We have discussed the clinical factors responsible for the progression of diabetic glomerulosclerosis and have suggested that the type of diabetes rather than the degree of control of blood glucose might be more important in determining the development and progression of diabetic glomerulosclerosis. Nevertheless, the possibility remains that successful control of blood glucose may prevent or retard the development of diabetic glomerulosclerosis.