Reexamination of phenoloxidase in larval circulating hemocytes of the silkworm, Bombyx mori

We have developed a modified method to detect phenoloxidase activity on hemocytes by using freshly prepared l-DOPA (1 mg/ml in 35% ethanol) to fix and incubate larval hemocytes. This method is more sensitive than the common method, in which hemocytes were fixed in 4% formaldehyde and then incubated with 2 mg/ml l-DOPA in water separately. Phenoloxidase assayed using this modified method can be inhibited by phenyltiourea (phenoloxidase inhibitor). After incubation with l-DOPA solution in ethanol, most prohemocytes, all plasmatocytes and young granulocytes are stained brown due to oxidation of l-DOPA into pigments, indicating that they have phenoloxidase. Oenocytoids are dimly stained because many of their cell inclusions have been released during the treatment. Large propidium-iodide-negative prohemocytes have strong phenoloxidase activity and are easily misunderstood as propidium-iodide-positive oenocytoids if the fluorescent method is not used for identification. Thus, in addition to oenocytoids and plasmatocytes, some prohemocytes and granulocytes in the silkworm also have phenoloxidase.

Two cases with transient lipoprotein lipase (LPL) activity impairment: evidence for the possible involvement of an LPL inhibitor

Two independent severe hypertriglyceridemic infants with transiently impaired lipoprotein lipase (LPL) activity were observed and the causes were explored. Both infants were female, born prematurely with low birth weight and developed hypertriglyceridemia (Fredrickson type V hyperlipidemia: high VLDL and low LDL/HDL) a few months after birth. While mass levels of their post-heparin plasma LPL and apoprotein C-II (apo C-II), a physiological activator of LPL, were normal, their post-heparin plasma LPL activities were remarkably impaired. Both of their mothers' post-heparin plasma LPL activities were slightly or moderately impaired as well, without a decrease in the LPL mass level. No mutations in the genes for LPL and apo C-II were detected in either patient. In an in vitro study with their serum at onset, we could not detect any distinct circulating inhibitors for LPL. There was no data supporting infection or autoimmune diseases, which might have an impact on LPL activity, during the follow-up period. Levels of their plasma triglyceride (TG) and total cholesterol (TC) were decreased quickly by a dietary intervention with medium-chain triglyceride (MCT) milk and kept normal even after stopping the intervention at around age 1 year. However, their low post-heparin LPL activity persisted and returned to normal at around age 2 years. Their low HDL cholesterol levels persisted even after recovery of the TG and TC levels, although lecithin:cholesterol acyltransferase (LCAT) and cholesterol-ester-transfer protein (CETP), two key enzymes of HDL metabolism, were normal throughout the course. The exact reasons why their post-heparin LPL activities were impaired for a certain period and why their HDL cholesterol levels have remained low are still unclear.

CONCLUSION

Transiently impaired LPL activity with no defect in LPL enzyme induced severe hypertriglyceridemia in infants. The transient occurrence of inhibitor(s) for LPL was proposed.

Effect of transglutaminase on reconstruction and physicochemical properties of collagen gel from shark type I collagen

The effects of microbial transglutaminase (MTGase) on type I collagen self-assembly and properties of reconstructed collagen fibrils from shark were investigated. Collagen self-assembly was accelerated with the addition of MTGase in dependence on that concentration. The relative amount of reconstructed collagen slightly decreased with MTGase. The diffusion coefficient of collagen gel was reduced by treatment with MTGase, and that suggested the reduction of mobility of the whole collagen network. At a high temperature, used to denature the collagen, MTGase-treated collagen gel remained as aggregates. By differential scanning calorimetry, the denaturation temperature of MTGase-treated collagen gel was about 2 degrees C higher than that of nontreated collagen gel. Treatment with MTGase yielded thermally stable cross-links in collagen molecules.

TGFbeta-Smad signalling in postoperative human lens epithelial cells

AIMS

To localise Smads3/4 proteins in lens epithelial cells (LECs) of fresh and postoperative human specimens. Smads3/4 are involved in signal transduction between transforming growth factor beta (TGFbeta) cell surface receptors and gene promoters. Nuclear localisation of Smads indicates achievement of endogenous TGFbeta signalling in cells.

METHODS

Three circular sections of the anterior capsule, one lens, and 17 capsules undergoing postoperative healing were studied. Immunohistochemistry was performed for Smads3/4 in paraffin sections of the specimens. The effect of exogenous TGFbeta2 on Smad3 subcellular localisation was examined in explant cultures of extracted human anterior lens epithelium.

RESULTS

The cytoplasm, but not the nuclei, of LECs of uninjured lenses was immunoreactive for Smads3/4. In contrast, nuclear immunoreactivity for Smads3/4 was detected in LECs during capsular healing. Nuclei positive for Smads3/4 were observed in monolayered LECs adjacent to the regenerated lens fibres of Sommerring's ring. Interestingly, the nuclei of LECs that were somewhat elongated, and appeared to be differentiating into fibre-like cells, were negative for Smads3/4. Fibroblast-like, spindle-shaped lens cells with nuclear immunoreactivity for nuclear Smads3/4 were occasionally observed in the extracellular matrix accumulated in capsular opacification. Exogenous TGFbeta induced nuclear translocation of Smad3 in LECs of anterior capsule specimens in explant culture.

CONCLUSIONS

This is consistent with TGFbeta induced Smad signalling being involved in regulating the behaviour of LECs during wound healing after cataract surgery.

Improved filler-matrix coupling in resin composites

Ineffective silane coupling between filler and matrix within dental composites is prone to accelerated in vivo degradation. In this study, we examined to what degree a procedure involving chemical decontamination of filler prior to silanization could improve the filler-matrix bonding, and thus the physico-mechanical properties, of composites. X-ray photoelectron spectroscopy revealed that filler-matrix coupling largely depended upon siloxane bridge (Si-O-Si) formation between the silica surface and the silane molecule, rather than on intermolecular bonding between adjacent silane molecules. Pre-silanization decontamination based upon boiling silica in 0.05-5% sodium peroxodisulfate, followed by ultrasonic rinsing in acetone, most effectively decontaminated filler. Consequently, it significantly improved the bonding of silane molecules to silanol groups at the silica surface. Experimental composites produced following pre-silanization decontamination of filler revealed a diametral tensile strength that was resistant to degradation by thermocycling.

Effect of temocapril hydrochloride on serum lipid levels in patients with hypertensive type 2 diabetes mellitus

The effect of angiotensin converting enzyme inhibitor, temocapril hydrochloride on the serum lipoproteins, and especially on the size of low density lipoproteins (LDL) of hypertensive diabetic patients, were studied. Temocapril hydrochloride (5 mg/day) was administered to 32 hypertensive type 2 diabetes patients for 16 weeks. During treatment, systolic and diastolic blood pressures decreased significantly from 162/95 mmHg to 138/76 mmHg at 16 weeks (p<0.001), and serum levels of total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) showed significant reduction, but those of HbA1c, triglycerides (TG) and high density lipoprotein cholesterol (HDL-C) showed no significant changes. LDL particle size evaluated by polyacrylamide gel disc electrophoresis was normalized from small size. It is concluded that temocapril hydrochloride favorably affects the serum lipoprotein metabolism of hypertensive type 2 dependent diabetes mellitus patients.

Detection of porphyrin using a short peptide immobilized on a surface plasmon resonance sensor chip

In this paper the development and feasibility of a novel detection system for a low molecular weight chemical, in which a peptide was utilized as a binding molecule, are described. Surface plasmon resonance (SPR) apparatus was used as a transducer. The porphyrin binding peptide, PSP2, was used as a model peptide ligand, while a porphyrin derivative, H(2)TMpyP, was used as a model low-molecular-weight chemical. PSP2 was covalently immobilized onto the SPR sensor chip and SPR measurement using the PSP2-immobilized chip for various concentrations of porphyrin was carried out. H(2)TMpyP was detectable in the range from 100 ng ml(-1) to 10 microg ml(-1) with a linear correlation and good precision and the PSP2-immobilized chip could be regenerated within 1 min after measurement in this system. From comparison of the detection manners of three porphyrin derivatives, the ability of a short peptide to discriminate between differences in molecular structure was demonstrated. Moreover, the self-assembled monolayer (SAM) of PSP2 was successfully prepared on the gold substrate and H(2)TMpyP could be detected using the PSP2-SAM chip.

Expression of transcription factor AP-1 in rat lens epithelial cells during wound repair

We examined the spatial and temporal expression patterns of proteins and mRNAs of the components of transcription factor activator protein 1 (AP-1) to examine the activation pattern of lens epithelial cells during lens wound repair following an anterior capsular injury. One eye of adult Wistar rats (n = 106) were used. After making a lens anterior capsule incision with a hypodermic needle, the affected eye was enucleated 0 and 30 min, 1, 3, 5, 8, 10, 15, 20, 24 hr after injury. Forty six globes were processed for in situ hybridization with oligonucleotide probes for c-fos, fosB, c-jun, junB and junD mRNAs, and 60 globes were immunohistochemically analysed using anti-c-Fos and anti-c-Jun antibodies. Normal lens epithelial cells expressed mRNA signals for junD, but not for c-fos, fosB, c-jun, and junB. mRNAs for c-fos, fosB, c-jun, and junB were detected in the whole lens epithelium from the vicinity to the wound to the equator from 30 min to 8 hr post-injury with their peaks after 30 min to 1 hr, but were no longer detected at 10 hr or later. Expression of c-fos mRNA in the equatorial lens cells was more marked than that of c-jun mRNA. Immunohistochemistry showed that c-Fos protein was expressed in the lens epithelial cells in both the anterior and equatorial regions of the injured lens from 1 to 10 hr after injury, and was no longer detected at 12 hr. C-Jun protein was detected only in the equatorial lens cells from 1 to 5 hr after injury, and was no longer detected at 8 hr. Lens epithelial cells except those in the equatorial region did not express c-Jun protein. These findings indicate that transcriptional activation of lens epithelial cells is initiated in the very early phase after the lens injury, i.e. 30 min post-injury, suggesting that AP-1 may play important roles in regulating lens cell behavior during lens wound repair in rats.

Role of hypertension, dyslipidemia and diabetes mellitus in the development of coronary atherosclerosis in Japan

The present study evaluated the effect of hypertension (HT), dyslipidemia and diabetes mellitus (DM) on the development of coronary atherosclerosis in the Japanese population, using a cross-sectional study of 433 patients (254 men and 179 women) aged 30 years or older who underwent coronary angiography for suspected or known coronary heart disease angina at 5 cardiology departments in the Fukuoka area between September 1996 and August 1997. Patients with a disease duration of 6 months or more were excluded. The main outcome measure was angiographically defined coronary artery stenosis and was found to a significant degree in 146 patients (33.7%). HT, DM, low levels of high-density lipoprotein cholesterol (HDL-C) and hypertriglyceridemia remained as significant coronary artery disease (CAD) risk factors even after controlling for age, sex, hospital, smoking, alcohol use, body mass index and leisure time physical activity. However, hypercholesterolemia was not a significant risk factor after adjusting for these variables. After controlling for these variables, DM, low HDL-C and hypertriglyceridemia were significant CAD risk factors for men, but only DM was a significant CAD risk factor in women. These results indicate that in Japan DM, low HDL-C and hypertriglyceridemia may be more important CAD risk factors than hypercholesterolemia.

Midazolam for continuous sedation in Japanese critical care patients: phase II study

This prospective study was undertaken to evaluate the efficacy and safety of midazolam as a sedative agent in 14 critically ill patients without coma admitted to the intensive care unit at Nihon University Itabashi Hospital, Japan. Adequate sedation (sedation score [SS] 4-6) was induced with 0.058- 0.372 mg/ kg midazolam and maintained with a dose range of 0.03-0.4 mg/kg per h. Most burn or trauma patients required higher midazolam doses than patients with cardiovascular disease. The most frequent adverse events observed were hypotension, heart-rate fluctuation and electrocardiogram abnormalities. Pharmacokinetic analysis of the population suggested that lower drug clearance rates correlated with presence of complications. Plasma concentrations (EC50) of SS 5, estimated by logistic regression analysis, varied among patients (mean 194 ng/ml). Midazolam infusion achieved successful sedation in this critical care setting, but the optimum dose differed by patient and was influenced by the presence of complications.

Comparison of Scheimpflug images of posterior capsule opacification and histological findings in rabbits and humans

PURPOSE

To compare the posterior capsule opacification in Scheimpflug photographic images produced by an electronic anterior eye segment analysis system with the histopathological findings in rabbits and humans.

SETTING

Department of Ophthalmology, Wakayama Medical College, Japan.

METHODS

Opacified posterior capsules were photographed using the EAS-1000 system (Nidek) and were then extracted during vitreous surgery for proliferative diabetic retinopathy or proliferative vitreoretinopathy in 2 patients. In rabbits, phacoemulsification and aspiration (PEA) with intraocular lens (IOL) implantation was performed. The IOL was implanted in the bag or in the sulcus. After intervals of healing, the posterior capsule was photographed with the EAS-1000 and the animals were then killed. In both clinical and experimental specimens, the posterior capsule was processed for light microscopic histology and immunohistochemistry.

RESULTS

Opacified human capsules were well imaged by the EAS-1000. Histology showed that lens epithelial cells proliferated with and without an accumulation of extracellular matrix. Details such as rolling of the capsulotomy edge were seen well. Regenerated lens fibers of Soemmering's ring were seen as a mass within the capsule. In the rabbit model, Scheimpflug images accurately represented the capsules as they appeared histologically.

CONCLUSION

The EAS-1000 system provided faithful, relatively high-resolution images that corresponded to the histologic findings in the posterior capsules after PEA-IOL surgery in humans and rabbits.

High cardiac angiotensin-II-forming activity in infarcted and non-infarcted human myocardium

The aims of this study were to compare human cardiac angiotensin-II-forming activity (AIIFA) between the intact area of control autopsy hearts without cardiac disease (n = 10) and the infarcted or non-infarcted area of autopsy hearts with myocardial infarction (MI, n = 7) and to determine responsible angiotensin-II-forming enzymes. Cardiac total and chymase-dependent AIIFAs were significantly higher in the infarcted and non-infarcted myocardium than those in non-MI heart, while angiotensin-converting enzyme-dependent AIIFA increased only in the infarcted myocardium. The density of chymase antibody-positive mast cells in the non-infarcted area of MI heart correlated positively with total or chymase-dependent AIIFA. Augmented AIIFA was also detected in the left atrium of post-MI hearts. Our results indicated that cardiac angiotensin II formation could be activated in the infarcted as well as in non-infarcted myocardium of the post-MI human heart.

Clinical significance of preheparin serum lipoprotein lipase mass in coronary vasospasm

The present study investigated the clinical significance of preheparin serum lipoprotein lipase (LPL) mass in coronary vasospasm by examining its relationship with the acetylcholine-induced coronary artery response in patients without angiographically demonstrable atherosclerotic coronary artery disease (CAD). The subjects were 39 men who had suspected CAD and who underwent coronary angiography. Coronary vasospasm was defined as a marked luminal narrowing or total occlusion provoked by the intracoronary administration of acetylcholine. Preheparin LPL mass was lower (p<0.05) in 25 subjects in whom vasospasm was induced by the acetylcholine provocation test than in the 14 subjects with a negative response. As regards preheparin LPL mass, the subjects with multiple vessel spasm had significantly low concentrations (p<0.05) compared with single vessel spasm, although serum lipid levels were not significantly different. Multiple regression analysis revealed only preheparin LPL mass had a significant absolute t-value (2.016) among the coronary risk factors. Low preheparin LPL mass is interpreted as reflecting an impaired acetylcholine-induced coronary relaxation in coronary vasospasm and preheparin LPL mass may be useful as a marker of early stage coronary atherosclerosis that is not detectable by angiography.