I-123 iodoamphetamine lung scanning in patients with ventilation-perfusion mismatching

I-123 IMP is a nonparticulate agent and becomes trapped by endothelial membranes in the pulmonary capillaries. Using I-123 IMP, the authors studied six patients with ventilation-perfusion mismatch. Three of six patients had pulmonary thromboembolism, and three had pulmonary hypertension. In comparison with conventional perfusion lung scanning using Tc-99m MAA, defect sizes visualized by I-123 IMP were smaller in all patients. I-123 iodoamphetamine is a useful agent for assessing the perfusion of pulmonary arterial microvasculature which Tc-99m MAA fails to penetrate.

[Experimental pneumonia with Pseudomonas aeruginosa in immunosuppressed guinea pigs as a model for biofilm-associated infection]

To establish a model where the role of bacterial biofilms in chronic pneumonia with Pseudomonas aeruginosa could be investigated, hydrocortisone-treated guinea pigs were given P. aeruginosa, strain 2126 by inhalation which were used throughout this study, in planktonic form. In these animals, the bacteria were recovered only from the lungs more than 4 weeks after infection. The persistence in bacterial colonization in the lungs coincided with the formation of glanulomatous lesions that surrounded spherical grains consisting of outer shell and inner bacterial colonies. The outer shell of grain was stained with ruthenium red and was presumed to be polyanionic and therefore to be a biofilm-like material. In normal animals without hydrocortisone-treatment, the number of neutrophils recovered from bronchoalveolar lavage fluid increased significantly from 3 hours after infection and subsequently the inhaled bacteria were eliminated from the lungs by day 3 of infection. This early influx of neutrophils into the lungs tended to be suppressed by treatment with hydrocortisone. The formation of grains did not take place in the lungs of normal animals, indicating the significant role of grain-formation in the initiation and the prolongation of bacterial colonization in the lungs. P. aeruginosa, strain 2126, incubated in saline formed thick biofilms on the surface of teflon piece. Levofloxacin (LVFX), a quinolone antibacterial, exhibited killing activity against the bacteria in in vitro-forming biofilms at MIC. In contrast, gentamicin (GM), an aminoglycosid antibiotic, and ceftazidime (CAZ), a beta-lactams antibiotic, showed no such killing activity at MIC. Treatment of this model with oral LVFX achieved complete eradication of the bacteria, whereas subcutaneous injection of GM or CAZ was hardly effective. The pharmacokinetic study on these antibacterials revealed that the doses used in this study were sufficient to obtain the pulmonary levels of these drugs far above MIC even in GM and CAZ. These data indicate that the outer shell of grains, a characteristic finding in the pulmonary lesions of this model, may be one of the forms of pseudomonal biofilms and that this model represents the significant role of biofilm mode of growth of P. aeruginosa in persistence in pulmonary colonization.

Effect of beta-blockade on regional left ventricular function in patients with dilated cardiomyopathy

It has been reported that beta-blockade has beneficial effects on the cardiac function and prognosis of patients with congestive heart failure. However, the mechanism for these effects remained unclear. This study compared the use of an angiotensin-converting enzyme (ACE) inhibitor (enalapril, 2.5 to 5.0 mg/day, or delapril, 15 to 30 mg/day) alone with the effects of beta-blockade therapy (metoprolol, 40 to 60 mg/day) coupled with an ACE inhibitor on global and regional left ventricular (LV) function in patients with dilated cardiomyopathy. In 12 patients with dilated cardiomyopathy, the global LV ejection fraction (EF), regional EF (rEF), and regional ejection time (rET) were determined by sector analysis of the radionuclide ventriculogram before and after therapy (duration 14 +/- 9 months). The coefficients of variation of rEF and rET were calculated as indexes of the heterogeneity of regional LV systolic wall motion. EF increased significantly from 20% +/- 8% to 30% +/- 8% (p < 0.05) in patients who received beta-blockade and an ACE inhibitor (n = 5). Furthermore, the coefficients of variation of rET decreased from 27% +/- 13% to 16% +/- 7% (p < 0.05). In contrast, patients treated with an ACE inhibitor only (n = 7) showed no significant improvements in any of these parameters. These results suggest that, compared with an ACE inhibitor alone, beta-blockade improves global and regional LV function in dilated cardiomyopathy by synchronizing myocardial contraction.

Long-term effects of dietary fiber supplementation on serum glucose and lipoprotein levels in diabetic rats fed a high cholesterol diet

We have shown that cholesterol-fed diabetic rats developed atheromatous lesions in the aorta and coronary arteries, which were not observed in cholesterol-fed diabetic rats receiving concomitant supplementation with 15% glucomannan, a soluble dietary fiber concentrate. The present study was designed to examine the effects of the dietary fiber supplementation on serum levels of glucose and lipoproteins in cholesterol-fed diabetic rats. Feeding a diet containing 1.5% cholesterol (wt/wt) and 0.37% cholic acid for 18 weeks to rats made diabetic by streptozotocin (35 mg/kg body weight, iv) produced moderate hyperglycemia and moderate hypercholesterolemia, the latter being characterized by high concentrations not only of low density lipoproteins but also intermediate density lipoproteins and very low density lipoproteins. These changes in serum lipoproteins and hyperglycemia were substantially reduced by 18 weeks of supplementation with glucomannan but high density lipoprotein cholesterol and triglyceride levels did not change after feeding a cholesterol-rich diet in the presence or absence of glucomannan supplementation. These results suggest that amelioration in hyperlipoproteinemia and hyperglycemia induced by the dietary fiber supplementation may help retard or prevent the atheromatous formation found in cholesterol-fed diabetic rats.

[Relationship between 123I-BMIPP imaging and cardiac function in acute myocardial infarction]

We evaluated the relationship between free fatty acid metabolism using 123I beta-methyl-iodophenyl pentadecanoic acid (BMIPP) and cardiac function in acute myocardial infarction. Twenty-five patients were examined with 123I-BMIPP and 201Tl dual SPECT. The 123I-BMIPP images were compared with the 201Tl images and the left ventricular wall motions. The 123I-BMIPP images showed a larger uptake defect than the 201Tl images. This was marked in the patients after revascularization therapy. The uptake decrease of 123I-BMIPP was in good agreement with the decrease in regional wall motion. The incidence of accordance was 79% of the wall segments. The correlation between 123I-BMIPP defect size and ejection fraction was higher (r = -0.54) than that of 201Tl (r = -0.44). Subtraction of ejection fractions four weeks and soon after infarction correlated well with the subtraction of 123I-BMIPP and 201Tl defect sizes (r = 0.55). In conclusion, 123I-BMIPP is more closely related to wall motion, than 201Tl and might be valuable in predicting the functional improvement of acute myocardial infarction.

Flow cytometric analysis of p53 expression during the cell cycle

Mutant p53 expressed in many types of carcinoma lacks an inhibitory function on cell growth, but its role has been unclear. We performed two-parameter flow cytometry (FCM) to elucidate the relationship between the expression of p53 and the cell cycle in A431 cells. Fluorescence in situ hybridization proved that an A431 cell had two p53 genes whereas chromosome 17 was tetraploid. FCM showed that A431 cells expressed constantly high levels of p53 during the cell cycle. Under conditions of both serum deprivation and presence of hydroxyurea, p53 expression was decreased throughout the cell cycle, and the bivariate DNA/p53 distribution pattern during the cell cycle did not change. The expression of p53 was reduced to 60% for the first 4 h after the addition of cycloheximide, and showed no significant changes at least for 20 h. Treatment with Triton X-100 increased p53 immunoreactivity throughout the cell cycle. These results indicate that mutant p53 differs from proliferative markers such as PCNA, Ki-67 and DNA polymerase-alpha, and that there are no links between the expression of p53 and the cell cycle in A431 cells.

Monitoring of venous blood flow velocity during interhemispheric approach for deep seated lesions

No precise intra-operative monitoring of venous blood flow has yet been developed for neurosurgical procedures. Preservation of the bridging veins is an important issue in order to minimize complications due to disturbances of venous blood flow during an interhemispheric approach. In the present study, venous blood flow velocity was measured in 11 anterior circulation aneurysms. The measurement was performed before brain retraction, during brain retraction and after completion of the procedure without brain retraction. In 6 cases, a bridging vein was dissected completely free from the dura up to its entry into the superior sagittal sinus (SSS group). In 5 cases, dura was cut parallel to the bridging vein so that the vein remained covered by the dura (dura group). Venous blood flow velocity was measured by microvascular Doppler sonography. The results show that venous blood flow can be better preserved during the retraction when the bridging vein remains covered with the dura than if the vein is dissected completely free from the dura.

Diabetes mellitus carrying a mutation in the mitochondrial tRNA(Leu(UUR)) gene

We screened 214 Japanese NIDDM (non-insulin-dependent) diabetic patients with a family history of diabetes for mutations in the mitochondrial tRNA(Leu(UUR)) gene using polymerase chain reaction-restriction fragment length polymorphism and direct sequencing. Six patients were identified as having an A to G transition at position 3243 (3243 mutation), but no patients were detected with a T to C transition at position 3271, in the mitochondrial tRNA(Leu(UUR)) gene. These two mutations were not present in 85 healthy control subjects. It was disclosed that the patients' mothers were also affected by diabetes mellitus in five of the six cases. In these six affected patients, the 3243 mutation shows variable phenotypes, such as the degree of multiple organ involvement, intrafamilial and interfamilial differences in disease characteristics, and the degree of the involvement of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) phenotype. Endocrinological examinations revealed that those diabetic patients with the 3243 mutation show not only beta-cell dysfunction, but also a defect in alpha-cell function, which is considered characteristic of diabetes with the 3243 mutation. When compared with 50 selected diabetic control subjects without the 3243 mutation, whose mothers, but not fathers, were found to have diabetes, it was established statistically that those with the 3243 mutation possess the following clinical characteristics; 1) the age of diabetes onset is lower, 2) they have lean body constitutions, and 3) they are more likely to be treated with insulin than control subjects. We suggest that diabetes with the 3243 mutation possesses phenotypes distinct from those in common forms of diabetes.

Body fat and muscle thickness distributions in untrained young females

Brightness-mode (B-mode) ultrasound was used to measure fat and muscle thicknesses on 44 untrained females (age = 18-29 yr, body density = 1.050 +/- 0.009 (SD)g.ml-1, %fat = 21.5 +/- 4.1%) at eight sites (triceps, biceps, forearm, subscapular, abdomen, quadriceps, hamstrings, and posterior calf). The correlation coefficients between fat and muscle thickness were not significant at any measurement site except for the triceps (r = -0.32, P < 0.05). Intercorrelation analyses among the eight sites were significant (P < 0.05) in almost all cases for fat thickness, while mainly between adjoining sites for muscle thickness. However, both tissues had a low degree of generality in thickness among sites. Fat thickness at all measurement sites was significantly correlated with body density except for the posterior calf; the best correlation was found with the quadriceps (r = -0.73). On the other hand, for muscle thickness, only the forearm and triceps were significantly correlated with body density. These results show 1) the extent of muscled and fat thicknesses are independent each of other within the same region, 2) fat and muscle thicknesses have a high degree of specificity in site distribution, and 3) fat thickness measurements determined from B-mode ultrasound may be of significant value assessing total body composition.

Autophosphorylation of insulin receptor in a patient with Werner's syndrome associated with insulin resistant diabetes mellitus

The tissue sensitivity to insulin was evaluated using the hyperinsulinemic euglycemic clamp technique in a 44-year old male with Werner's syndrome associated with diabetes mellitus. In addition, the autophosphorylation of insulin receptors and the number of autophosphorylated insulin receptors were measured in his erythrocytes by a new enzyme-linked immunosorbent assay. He had an increased serum insulin level (30.5 microU/ml) in addition to hyperglycemia (226 mg/dl), suggesting that he had insulin-resistant diabetes mellitus. A clamp study revealed that his insulin-stimulated glucose disposal rate (2.80 mg/kg/min) was comparable to that in noninsulin-dependent diabetes mellitus (4.14 +/- 1.94 (SD) mg/kg/min, n = 23). The number of autophosphorylated insulin receptors per 300 microliters of erythrocytes was also identical to that in normal control subjects. In addition, the autophosphorylation of insulin receptors determined at six different insulin concentrations was within the normal range, even when it was expressed as per 300 microliters of erythrocytes as well as per unit receptor. These results demonstrate that insulin resistance in the patient with Werner's syndrome is caused by a defect that cannot be detected by means employed in this study, and suggest that the defect is present at the steps distal to the autophosphorylation of tyrosine kinase of insulin receptors.

In vitro and in vivo activity of DQ-2556, a new cephalosporin

The antibacterial activity of DQ-2556, a new cephalosporin, was compared with that of cefepime, cefpirome, and other antibiotics. DQ-2556 was more active than cefepime and less active than cefpirome against gram-positive bacteria. DQ-2556 was the most active compound against most members of the Enterobacteriaceae, such as Escherichia coli, Klebsiella, Proteus, Salmonella spp., and Shigella spp., and Haemophilus influenzae and Neisseria gonorrhoeae. In vivo, treatment with DQ-2556 was as or more efficacious than that with reference compounds in both systemic and respiratory tract infections in mice. DQ-2556 achieved higher concentrations than cefepime and cefpirome in lungs and kidney of mice.

Long-term efficacy and tolerability of pravastatin in hypercholesterolemia in patients with non-insulin-dependent diabetes mellitus. Hyogo Pravastatin Study Group

This study reports the result of a 12-month, open-label multicenter study of the efficacy and tolerability of pravastatin in the management of hypercholesterolemia associated with non-insulin-dependent diabetes mellitus. Pravastatin produced a decrease, in 138 diabetic and 51 non-diabetic patients, in total serum cholesterol by 19 and 20%, in low-density lipoprotein (LDL) cholesterol by 25 and 29%, in apolipoprotein B by 15 and 19% and in triglycerides by 8 and 5%, respectively. High-density lipoprotein cholesterol levels were increased by 9% in both groups. All of these changes were significant (P < 0.001) except for triglycerides changes in non-diabetic patients, where the change was not significant and no significant differences were observed between the two groups. These favorable effects on LDL cholesterol and apolipoprotein B were not influenced by gender, the type of diabetic therapy, baseline hemoglobin A1c levels and by the presence of hypertension or gross proteinuria, although a decrease in the two variables were less in those with body mass index > or = 26.4 kg/m2 or in those with age < 60 years. Adverse experiences were similar between treatment groups and the drug was well tolerated. Only one diabetic patient was withdrawn from the study because of pruritus. Pravastatin produced no change in fasting plasma glucose concentrations and hemoglobin A1c levels in diabetic patients throughout the study. Pravastatin was generally effective in improving the serum lipids of hypercholesterolemic diabetic patients.

IL-2 can support growth of CD8+ T cells but not CD4+ T cells of human IL-2 receptor beta-chain transgenic mice

We have generated transgenic mice expressing the human (h) IL-2R beta-chain on lymphoid cells under the control of the mouse H-2Kd promoter. Spleen cells and thymocytes of the transgenic mice were cultured in the presence of 5 nM hIL-2. After a 10-day culture, the expanded populations were analyzed by flow cytometry and shown to be composed of CD8+ T cells and gamma delta T cells. Surprisingly, CD4+ T cells of the transgenic mice did not proliferate in response to hIL-2, although the CD4+ T cells expressed the transgenic hIL-2R beta-chain as well as the endogenous gamma-chain on their surface and bound 125I-labeled IL-2. When CD4+ T cells of the transgenic mice were stimulated with anti-CD3 mAb, the CD4+ T cells proliferated in response to hIL-2. These findings suggest that CD4+ T cells may require another triggering signal to respond to IL-2 even when IL-2Rs are expressed. By contrast, CD8+ T cells and gamma delta T cells respond to IL-2 as long as IL-2Rs are expressed.

IL-2 can support growth of CD8+ T cells but not CD4+ T cells of human IL-2 receptor beta-chain transgenic mice

We have generated transgenic mice expressing the human (h) IL-2R beta-chain on lymphoid cells under the control of the mouse H-2Kd promoter. Spleen cells and thymocytes of the transgenic mice were cultured in the presence of 5 nM hIL-2. After a 10-day culture, the expanded populations were analyzed by flow cytometry and shown to be composed of CD8+ T cells and gamma delta T cells. Surprisingly, CD4+ T cells of the transgenic mice did not proliferate in response to hIL-2, although the CD4+ T cells expressed the transgenic hIL-2R beta-chain as well as the endogenous gamma-chain on their surface and bound 125I-labeled IL-2. When CD4+ T cells of the transgenic mice were stimulated with anti-CD3 mAb, the CD4+ T cells proliferated in response to hIL-2. These findings suggest that CD4+ T cells may require another triggering signal to respond to IL-2 even when IL-2Rs are expressed. By contrast, CD8+ T cells and gamma delta T cells respond to IL-2 as long as IL-2Rs are expressed.

Red blood cell sorbitol in diabetic children

When red blood cells (RBC) were incubated with various concentrations of glucose, the RBC sorbitol level increased in a concentration-dependent manner. The elevated RBC sorbitol level was not reduced by further incubation in a glucose-free medium. In both diabetic and non-diabetic children, an increase of RBC sorbitol levels occurred in the oral glucose tolerance test and the return to baseline was delayed in diabetics compared with non-diabetics. In the majority of diabetics (87%), RBC sorbitol levels exceeded the upper limit of the normal range, which was arbitrarily determined as the mean + 2 s.d., in healthy non-diabetic children and adults. A good correlation was observed between RBC sorbitol levels and plasma glucose levels (r = 0.644). In both diabetics and non-diabetics, no correlation was observed between RBC sorbitol levels and age, and in diabetics the RBC sorbitol level was not related to the duration of disease. A good correlation was observed between RBC sorbitol levels, and hemoglobin Alc (HbAlc) or fructosamine levels in diabetic children.

Photoreceptor differentiation of retinoblastoma: an electron microscopic study of 29 retinoblastomas

Retinoblastomas exhibit a unique form of differentiation to produce cell elements similar to those seen in a photoreceptor cell. An ultrastructural study was performed on 29 cases of retinoblastoma to further clarify the cytologic characteristics of the tumor cells. The age of the retinoblastomas averaged 17.1 months and the tumor cells showing photoreceptor differentiation were demonstrated in 10 cases (35%). The findings were especially notable in retinoblastomas with Flexner-Wintersteiner rosette formation (seven cases, 28%). Similar photoreceptor differentiation was also evident in solid cell clusters without rosette formation (four cases, 14%). The presence of photoreceptor elements was assumed to be significantly frequent both in Flexner-Wintersteiner rosettes and in the solid cell clusters. The cell cytoplasm also showed proliferation of long mitochondria and microtubules, reflecting photoreceptor differentiation. The hereditary-type retinoblastoma showed more advanced cell differentiation than the non-hereditary type. Photoreceptor differentiated retinoblastoma showed rather indolent growth compared with the undifferentiated type, and the former can expect a curative treatment by operation. These observations provide additional findings of the biological nature of retinoblastomas.

Characteristics of femtosecond pulses near 1.5 microm in a self-mode-locked Cr(4+):YAG laser

The operating characteristics of a self-mode-locked Cr(4+) :YAG laser that produces sub-100-fs pulses are described. Stable, nearly transform-limited pulses are obtained at a central wavelength longer than 1.50 microm, and the spectrum of the wavelength is extended past 1.60 microm, over the net gain bandwidth of the laser material. The group-velocity dispersion and the third-order dispersion of the Cr-doped YAG rod are measured by a Fourierindicating that the group-velocity dispersion vanishes at a transform interferometric cross-correlation technique, wavelength of 1.59 microm.

Circadian rhythms of adenosine triphosphate contents in the suprachiasmatic nucleus, anterior hypothalamic area and caudate putamen of the rat--negative correlation with electrical activity

Contents of adenosine triphosphate (ATP) in the suprachiasmatic nucleus (SCN), anterior hypothalamic area (AH) and caudate putamen (CPu) were determined every 4 h in rats kept under constant dark conditions. All tested regions of the brain exhibited circadian rhythms in ATP content. Among these, the amplitude of the rhythm was largest in the SCN. Peaks of the ATP content were observed at circadian time 18 in the SCN, 6 in the AH and 10 in the CPu. In view of the observation that at around these peak times electrical or glucose uptake activity of each brain region was lowest, the present result suggests that ATP content is negatively correlated with electrical or glucose uptake activity.

Multidirectional contraction of human hypertrophied prostate

1. The purpose of the present investigation is to evaluate muscle contraction in two directions (longitudinal and circumferential to urethra) physiologically and morphologically for alpha-adrenoceptor agonists. 2. Norepinephrine (10(-7)-10(-4) M), phenylephrine (10(-7)-10(-4) M) and clonidine (10(-7)-10(-4) M) induced contractions in a dose-dependent manner on human prostate from patients with benign prostatic hypertrophy (BPH). 3. No significant differences were observed between longitudinal and circumferential directions of human prostate in 50% of the maximal muscle contraction (EC50 values) and the maximal muscle contractions caused by any agents used. 4. Morphometric analysis for muscle in prostates was performed using formalin-fixed, paraffin-embedded sections stained by the Mallory-Azan method. 5. There was no significant difference in the density of the muscle area between longitudinal and circumferential directions of prostatic strips. 6. These results suggest that there are no significant differences in responsiveness of alpha-adrenoceptor agonists and the smooth muscle contents in longitudinal and circumferential directions to urethra, for human hypertrophied prostate.