Predictors of healthy aging in men with high life expectancies.

OBJECTIVE: The purpose of this study was to identify risk factors that consistently predict staying healthy in contrast to developing clinical illness and/or physical and mental impairments. METHODS: More than 8000 men of Japanese ancestry were followed for 28 years with repeat examinations and surveillance for deaths and incident clinical illness. Physical and cognitive functions were measured in 1993. Measures of healthy aging included surviving and remaining free of major chronic illnesses and physical and cognitive impairments. RESULTS: Of 6505 healthy men at baseline, 2524 (39%) died prior to the final exam. Of the 3263 available survivors, 41% remained free of major clinical illnesses, 40% remained free of both physical and cognitive impairment, and 19% remained free of both illness and impairment. The most consistent predictors of healthy aging were low blood pressure, low serum glucose, not smoking cigarettes, and not being obese. CONCLUSIONS: Beyond the biological effects of aging, much of the illness and disability in the elderly is related to risk factors present at midlife.     

Progressive cerebellar ataxia with diencephalic symptoms (Toyokura)--a case report]

We reported a 16-year-old boy suffering from dwarfism, diabetes insipidus and progressive cerebellar ataxia. The disease entity here reported was originally reported by Toyokura et al. in 1967, under the title of "progressive cerebellar ataxia with diencephalic symptoms". Ten similar cases have been reported in literature so far, all of which were Japanese except for two sibling cases reported by Robinson et al. The topographic distribution of the lesion in this disorder, however, had been conjectured to be at spinocerebellar tract and diencephalon only on a clinical ground. By applying the modern techniques of neuroimaging, electrophysiological and endocrinological test in our patient, the authors were able to demonstrate the lesion of the disorder more precisely. CT and MRI of the head revealed degenerative changes in deeper structures of the bilateral cerebellar hemispheres. ABR abnormality suggested the presence of a wide lesion in the brain stem. Pituitary hormones (GH and ACTH) sufficiently responded to the loading of hypothalamic hormones such as growth hormone releasing factor and corticotropin releasing factor, in spite of poor responses of GH under the insulin stimulation or sleep. These clinical and laboratory findings suggested that the patient has a systemic degenerative disease which preferentially involves hypothalamus, brain stem and cerebellum.     

Renal tissue gas tensions during hemorrhagic shock

To evaluate the development of renal hypoxia during hemorrhagic shock, fourteen dogs were induced in this study. The animals were divided equally into a group in which mean arterial pressure (MAP) was kept at 50mmHg (group 1), and into another where MAP was kept at 40mmHg for 180mim (group 2). Renal tissue gas tensions were determined by a mass spectrometer. In the 50-mmHg group, renal tissue oxygen tension (Pr_{O 2}) dropped for 15min following hemorrhage, remained constant for 90min, then fell further for 150min before a plateau was established. In the 40-mmHg group, the Pr_{O 2} dropped for 90min before reaching a plateau. The second Pr_{O 2} decline occurred at the same level in both the 50-mmHg group and the 40-mmHg group. The point at which the same Pr_{O 2} level occurred for each group suggests the cessation of oxygen consumption and the conditions of renal hypoxia. It is assumed that renal hypoxia occurs in 120min at a MAP of 50-mmHg and in 60min at a MAP of 40mmHg.(Murakawa K, Izumi R, Kobayashi A: Renal tissue gas tentions during hemorrhagic shock. J Anesth 3: 10–15, 1989)     

Effect of halothane and enflurane on hepatic blood flow and oxygen consumption in dogs

We investigated the relative effects of 0.5, 1.0, 1.5, 2.0 MAC halothane and enflurane, and concurrent noxious stimulus on hepatic blood flow and oxygen consumption in 14 mongrel dogs randomly divided into groups of seven each. Hepatic arterial and portal venous blood flow (HABF and PVBF, respectively) were measured continuously using ultrasonic transit time flow meter. Mean arterial blood pressure (MAP), cardiac index (CI), hepatic oxygen supply, and hepatic oxygen consumption (H _{O 2}) were measured. Halothane significantly deceased HABF, but not PVBF in a dose dependent manner. Enflurane did not affect HABF and PVBF significantly. MAP and CI decreased in both groups, with halothane producing more marked decreases than enflurane. H _{O 2} did not change with enflurane, but did with halothane, producing significant differences, with halothane being greater at 1.5, 2.0 MAC. A noxious stimulus only caused minor change in blood flow. The results suggest that liver blood flow and oxygen consumption are affected differently by halothane and enflurane and that halothane has a stronger tendency to cause an imbalance between liver oxygen supply and consumption than dose enflurane.(Masaki E, Yasuda N, Tanifuji Y et al.: Effect of halothane and enflurane on hepatic blood flow and oxygen consumption in dogs. J Anesth 3: 118–122, 1989)     

Drug Binding to α1-Acid Glycoprotein Studied by Circular Dichroism

The interactions of acidic and basic drugs with ₁-acid glycoprotein (₁-AGP) were investigated using circular dichroism (CD) measurements. Extrinsic Cotton effects were generated by the binding of drugs to ₁-AGP. The CD data suggested the presence of a single binding site on the ₁-AGP molecule. The induced ellipticities of the acidic drug–₁-AGP system decreased with increasing pH, while the ellipticities for the basic drugs increased with pH. The ellipticities for all drugs were reduced by the addition of fatty acids. Furthermore, the induced ellipticities decreased in the presence of cesium chloride for basic drugs bound to ₁-AGP. The extrinsic Cotton effects therefore appear to result from hydrophobic interaction with ₁-AGP for the acidic drugs and from hydrophobic and electrostatic interactions for the basic drugs.     

MR imaging of renal cell carcinoma: associations among signal intensity, tumor enhancement, and pathologic findings

The purpose of this study was to compare the MR characteristics of renal cell carcinomas against histologic findings and to assess the correlations among signal intensity, tumor enhancement, and pathologic findings. Fifty-four patients (56 lesions) were examined by MR imaging and then underwent partial or radical nephrectomy. The pathologic diagnosis of all lesions was renal cell carcinoma. All MR examinations were performed as dynamic studies using the same 1.5-T scanner. MR characteristics were compared against pathologic findings after resection, and the correlations among signal intensity, tumor enhancement, and pathologic findings were then assessed. A significant correlation was observed between tumor grade and tumor enhancement, with G3 lesions tending to show little enhancement. Regardless of the histologic classification, G3 tumors were found to contain highly heterotypic cancer cells and very few vessels by histopathologic examination. No significant correlations were noted between the other MR characteristics and pathologic findings. Renal cell carcinomas showing little enhancement tend to be highly malignant lesions based on the pathologic findings. Special consideration is required for these tumors with regard to the selection of surgical intervention and follow-up observation.     

Differential diagnosis of adrenal masses by chemical shift and dynamic gadolinium enhanced MR imaging

Chemical shift MRI is widely used for identifying adenomas, but it is not a perfect method. We determined whether combined dynamic MRI methods can lead to improved diagnostic accuracy. Fifty-seven adrenal masses were examined by chemical shift and dynamic MR imaging using 2 MR systems. The masses included 38 adenomas and 19 non-adenomas. In chemical shift MRI studies, the signal intensity index (SI) was calculated, and the lesions classified into 5 types in the dynamic MRI studies. Of the 38 adenomas studied, 37 had an SI greater than 0. In the dynamic MRI, 34 of 38 adenomas showed a benign pattern (type 1). If the SI for the adenomas in the chemical shift MRI was considered to be greater than 0, the positive predictive value was 0.9, and the negative predictive value was 0.94 and kappa = 0.79. If type 1 was considered to indicate adenomas in the dynamic MRI, the corresponding values were 0.94, 0.81 and kappa = 0.77 respectively. The results obtained when the 2 methods were combined were 1, 0.95 and kappa = 0.96 respectively. The chemical shift MRI was found to be useful for identifying adenomas in most cases. If the adrenal mass had a low SI (0 < SI < 5), dynamic MRI was also found to be helpful for making a differential diagnosis.     

Electron Microscopic Studies on IgA Nephropathy

We carried out electron microscopic studies on renal tissues from 9 patients with IgA nephropathy. Electron dense deposits were present in the mesangial area in all cases, subendothelial deposits in 4, and subepithelial deposits in only one. In basement membrane, segmental swelling and rarefaction of basement membrane substance were observed. In some cases the degenerated basement membrane substance protruded through the dilated endothelial fenestration into capillary lumina. Focal splitting, attenuation, mouse eaten appearance, and herniation of basement membrane were seen in a high incidence. Mesangial cells possessed well developed rough endoplasmic reticulums and polysomes. In the peripheral areas of mesangial cell cytoplasm, there was accumulation of electron dense substance and this was occasionally continuously present in the mesangial matrix. There was segmental swelling of endothelial cell cytoplasm, resulting in loss of fenestration. Epithelial cells had well developed rough endoplasmic reticulums and polysomes. Segmental foot process fusion was seen, and these processes, regardless of fusion, became electron denser in the area close to the basement membrane. Multivesiculated bodies were present in all cases in the epithelial cells and in 7 cases in the endothelial cells. Spherical microparticles were present in 3 cases in the urinary space or between the basement membrane and the epithelial cells.     

An assessment of PKI and networked electronic patient record system: lessons learned from real patient data exchange at the platform of OCHIS (Osaka Community Healthcare Information System)

To enhance medical cooperation between the hospitals and clinics around Osaka local area, the healthcare network system, named Osaka Community Healthcare Information System (OCHIS), was established with support of a supplementary budget from the Japanese government in fiscal year 2002. Although the system has been based on healthcare public key infrastructure (PKI), there remain security issues to be solved technically and operationally. An experimental study was conducted to elucidate the central and the local function in terms of a registration authority and a time stamp authority in contract with the Japanese Medical Information Systems Organization (MEDIS) in 2003. This paper describes the experimental design and the results of the study concerning message security.     

Analysis of small dense LDL in patients with type 2 diabetic mellitus by the modified Krauss method using an internal standard

In patients with Type 2 diabetes mellitus (Type 2 DM), the relationship between the prevalence rate of small dense LDL (sdLDL) and parameters of lipid metabolism was analyzed using the method devised by modified Krauss method using apoferritin as an internal standard. The prevalence rate of sdLDL was 34% compared with it of normal subjects in this study. When the severity of Type 2 DM was classified into three groups of the HbA1c value, neither the sdLDL size nor its prevalence rate differed significantly depending upon the severity of the Type 2 DM. Also, when the prevalence rate of sdLDL was analyzed in relation to the severity of complications, i.e., of microangiopathy (retinopathy and nephropathy) or macroangiopathy (cerebral infarction), there was no significant difference in the prevalence rate of sdLDL depending on the severity of any of these complications. On the other hand, the prevalence rate of sdLDL was found to be correlated with the serum TG level. The serum level of TG-rich remnants (metabolites of TG) was also high in patients with sdLDL. It should take notice that the assessment of sdLDL should be used the authorized method for the evaluation. Thus it is concluded that the levels of sdLDL were important in evaluation of Type 2 DM. The prevalence rate of sdLDL did not correlate with the severity, nor the modalities for the complications of Type 2 DM.