Genetic diagnosis of cardiovascular diseases and the therapeutic application

We have examined the effect of neutralizing TGF-beta antibodies on cisplatin-mediated cytotoxicity against MDA-231 human breast tumor cell spheroids. These tridimensional in vitro systems have been shown to recapitulate the drug sensitivity pattern of tumor cells in vivo. MDA-231 tumor cell spheroids exhibit higher protein levels of the cyclin-dependent kinase (Cdk) inhibitors p21 and p27 and >10-fold lower Cdk2 activity compared to adherent cell monolayers, as well as pRb hypophosphorylation, a predominant G1 population, and a cisplatin 1-h IC50 of approximately 100 microM. Treatment of MDA-231 cells in monolayer with cisplatin for 1 h, subsequently grown as spheroids, increased steady-state TGF-beta1 mRNA levels, secretion of active TGF-beta, cellular Cdk2 activity, pRb phosphorylation, and p21 protein levels, while downregulating p27. Accumulation of cells in G2M and progression into S were noted 48 h after treatment with 100 microM cisplatin. We tested whether drug-induced upregulation of TGF-beta1 and p21, perhaps by preventing cell cycle progression, were protective mechanisms against drug-mediated toxicity by using neutralizing anti-TGF-beta antibodies. Anti-TGF-beta antibodies diminished the induction of p21, enhanced the activation of Cdk2, and facilitated progression into S and G2M following cisplatin treatment. This resulted in a >twofold enhancement of drug-induced DNA fragmentation and a shift in the cisplatin 1-h IC50 from 100 to <10 microM. These data suggest that tumor cell TGF-beta1 may protect from DNA damage and that postchemotherapy administration of TGF-beta inhibitors may facilitate progression beyond G1/S, potentially increasing the efficacy of cytotoxic chemotherapy.     

Sarcoplasmic reticulum genes are selectively down-regulated in cardiomyopathy produced by doxorubicin in rabbits

The clinical utility of doxorubicin, an antineoplastic agent, is limited by its cardiotoxicity. Our objective was to determine whether expression of genes encoding proteins that affect Ca2+ homeostasis were altered in the hearts of rabbits chronically treated with doxorubicin. Twelve male New Zealand white rabbits received an injection of doxorubicin (2.5 mg/kg i.v.) once a week for 8 weeks. Eight rabbits were similarly injected with saline as controls. The cardiac function of both groups was evaluated 8 weeks after the final injection, as were the levels of expression of mRNA for Ca2+ transport proteins in the sarcoplasmic reticulum and plasma membrane. The amount of the sarcoplasmic reticulum Ca2+-ATPase and the Ca2+ uptake capacity of the protein were also quantitated. Cardiac output was significantly decreased in the doxorubicin-treated group (71+/-21 ml/min, P<0.05) compared with the control group (118+/-15 ml/min). The mRNA levels for the sarcoplasmic reticulum proteins were significantly diminished in the doxorubicin-treated hearts: ryanodine receptor-2 (relative expression level compared with controls, 0.35+/-0.13, P<0.01), sarcoplasmic reticulum Ca2+-ATPase (0.56+/-0.13, P<0.01), phospholamban (0.62+/-0.20, P<0.01) and cardiac calsequestrin (0. 57+/-0.26, P<0.01). In addition, both relative amount of sarcoplasmic reticulum Ca2+-ATPase protein (doxorubicin-treated group, 69+/-17% of control, P<0.01) and the Ca2+ uptake capacity (46. 9+/-9.8 nmol Ca2+/mg protein-5 min in doxorubicin group v 63.2+/-10. 4 in the control group, P<0.01) were concomitantly decreased with its mRNA expression level. Conversely, the mRNA levels for the plasma membrane proteins did not differ from those of control rabbits: the dihydropyridine receptor (relative expression level, 1. 03+/-0.30, N.S.), plasma membrane Ca2+-ATPase (0.93+/-0.33, N.S.) and the Na+/Ca2+ exchanger (0.87+/-0.34, N.S.). These findings suggest that a selective decrease in mRNA expression for sarcoplasmic reticulum Ca2+ transport proteins is responsible for the impaired Ca2+ handling, and thus, for the reduced cardiac function seen in the cardiomyopathy induced in rabbits by the long-term treatment with doxorubicin.     

Factors affecting the nocturnal decrease in blood pressure: a community-based study in Ohasama

OBJECTIVE: To investigate factors affecting the nocturnal decrease in blood pressure. DESIGN: A cross-sectional study of 823 community-based untreated subjects aged > 20 years. Screening and ambulatory blood pressures were measured and the effects of age and the ambulatory blood pressure on the nocturnal decrease were examined. RESULTS: The magnitude of the decrease and the percentage decrease in the nocturnal blood pressure increased with increasing daytime ambulatory blood pressure and decreased with increasing night-time ambulatory blood pressure. Although the magnitude of the nocturnal decrease in blood pressure increased with increasing daytime blood pressure, the nocturnal blood pressure levels in hypertensives were still higher than those in normotensive subjects. The magnitude decreased with increasing age for men but not for women, whereas the percentage decrease decreased with increasing age both for men and for women. The SD of the 24 h blood pressure correlated strongly to the magnitude of the nocturnal decrease (systolic blood pressure r = 0.62, P < 0.0001; diastolic blood pressure r = 0.52, P < 0.0001), suggesting that the SD of the 24 h blood pressure is representative of the nocturnal decrease. A minimal nocturnal decrease was observed frequently in elderly normotensive men but infrequently in hypertensive individuals from the general population. A marked nocturnal decrease was observed frequently in hypertensive women aged > 70 years. CONCLUSION: Although the magnitude of the nocturnal decrease in blood pressure increased with increasing daytime blood pressure, the nocturnal blood pressure levels increased with increasing daytime ambulatory blood pressure. Therefore, the blood pressure in hypertensive subjects should essentially be lowered throughout the 24 h period. A marked nocturnal decrease in blood pressure in some elderly hypertensive women was observed without treatment. The nocturnal blood pressure levels of such subjects should be considered during treatment.     

Miliary tuberculosis

Seventy-four cases of miliary tuberculosis were studied retrospectively. Most common symptoms and findings were fever (97.3%), elevated serum alkaline phosphatase (67.6%), and nodular shadows in the chest X-ray films (98.6%). The other findings were enlarged mediastinal lymph node (17.6%), lung cavities (23.0%), consolidation (35.1%), and pleural effusion (27.0%). Sputum cultures and urine cultures were positive for Mycobacterium tuberculosis in 76.8% and 58.6% respectively. Biopsies were positive for bone marrow aspiration (61.5%), lymph node biopsies (83.3%), liver biopsies (100%), and lung biopsies (100%). Though antituberculosis therapy was successful in most of the patients, seven patients died of miliary tuberculosis, of whom four developed adult respiratory distress syndrome.     

Specific inhibition of Na+,K(+)-ATPase activity by atractylon, a major component of byaku-jutsu, by interaction with enzyme in the E2 state

Acute myocardial infarction (AMI) is known to be associated with a complex neuroendocrine activation, especially concerning sympathetic and renin-angiotensin systems, cortisol, atrial natriuretic peptide and endothelin. Results of our study show that the vasoactive intestinal peptide (VIP), also, is early involved in the neuroendocrine activation occurring in AMI. Plasma concentration of VIP, significantly increased in AMI patients within 6 hours after the onset of chest pain, soon decreased and remained below than normal along the first week. At the 14th day of the AMI, plasma levels of VIP returned into the normal range. A significant increase of VIP plasma concentration is detectable in the first hours of AMI in survived as compared with died patients. The phenomenon seems to be a suitable process to provide an endogenous support to the ischemic heart and to counteract the negative effects of other neuroendocrine activated factors.     

Selective inhibition of Src protein tyrosine kinase by analogues of 5-S-glutathionyl-beta-alanyl-L-dopa

Twelve analogues of the antibacterial phenolic peptide 5-S-glutathionyl-beta-alanyl-L-dopa (5-S-GA-L-D: 1) were synthesized via orthoquinones using tyrosinase. Several synthesized compounds inhibited the v-Src autophosphorylation tyrosine kinase reaction with an IC50 value comparable to that of herbimycin. The inhibition of c-Src substrate phosphorylation was much less active than v-Src autophosphorylation inhibition. The analogues showed no effects on substrate phosphorylation by epidermal growth factor receptor (EGFR), and this selectivity is the most characteristic feature of the analogues (1-12).     

Characteristics of laser diodes with a partially intermixedGaAs-AlGaAs quantum well

Laser diodes (LD's) with a partially intermixed quantum-well (QW) active layer are fabricated by Zn out-diffusion from a p-cladding layer to the QW region. The dependencies of the degree of intermixing, measured by the photoluminescence (PL) shift, on Zn concentration of the p-cladding layer (P_clad) and the Al content of the guiding layer (X_g) in a separate-confinement-heterostructure (SCH) are investigated. P_clad changes in the range from 1×10 ¹⁸ cm^-3 to 4×10¹⁸ cm^-3 and X_g changes in the range from 0.21-0.37. When P_clad is 2×10¹⁸ cm^-3 and X_g is 0.37, large bandgap energy shift of 96.1 meV is observed. The lasing wavelengths of the LD's, with the partially intermixed QW, are blue-shifted linearly with increasing P_clad and X_g. For the bandgap energy shift of 66.8 meV by PL, the threshold current density is increased by 33% from that of the nonintermixed LD. Reliability of LD's with the partially intermixed QW is investigated for the first time. In spite of a large degree of intermixing the reliability of the LD with the partially intermixed QW of 66.8 meV energy shift by PL is the same as the nonintermixed one, which is confirmed by the aging test of 2500 hours at 45°C with the output power of 1 W under CW operation     

A kinetic investigation of thermally initiated emulsion copolymerization of styrene and methylmethacrylate without conventional initiators

The thermally initiated emulsion copolymerization of styrene (ST) and methyl methacrylate (MMA) was carried out in the absence of conventional initiators. The hydroperoxide (HPO) concentration in the monomers, sodium dodecyl sulfate (SDS), deionized water, and the formulation of those for emulsion copolymerization were measured. The HPO concentration in ST and MMA increased with the storage time, and were considered to be the major sources of HPO. The thermal decomposition of hydroperoxide in monomers, the thermal initiation of ST by Mayo mechanism, and the complex formation between SDS and the monomers were proposed to be three main sources of the radical generation. It was confirmed that new polymer particles were generated throughout the polymerization process, and consequently resulted in a broader distribution of polymer particle size, compared with that for conventional emulsion polymerization. Approximately 80 wt % of monomer conversion was obtained in the presence of SDS at 373 K in 24 h. The initiation rate of the 30 wt % monomer charge was faster than those of 10 wt % and 20 wt % monomer charge. The latex instability at higher solid content was improved by adding electrolyte to promote the electrostatic repulsion force between the polymer particles. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 455–467, 2002; DOI 10.1002/app.2343     

3D-CT cystography with perspective volume-rendering

We evaluated the clinical utility of 3D-CT cystography using the perspective volume rendering technique in 5 patients with disorders of the urinary bladder and prostate. Unlike the conventional orthostatic volume-rendering technique, the capability of optional visual point settlement in the urinary bladder precluded cutting a subset of acquired data for luminal inspection, and permitted observation closer to lesions. Consequently, the technique enabled the evaluation of the accurate size, shape, and relation to adjoining mucosa and the region shaded by bulky tumor. 3D-CT cystography using the perspective volume-rendering technique facilitated 3-D inspection of the bladder lumen.     

Simultaneously found transient hypothyroidism due to Hashimoto's thyroiditis, autoimmune hepatitis and isolated ACTH deficiency after cessation of glucocorticoid administration

We present a 42-year-old woman with concomitant transient hypothyroidism due to Hashimoto's thyroiditis, autoimmune hepatitis and isolated ACTH deficiency. Two months after ceasing prednisolone (5 mg/day) for uveitis, she was discovered incidentally to have liver dysfunction with hypergammaglobulinemia, later diagnosed as autoimmune hepatitis by histological examination of the biopsied liver. In addition, primary hypothyroidism due to Hashimoto's thyroiditis and secondary hypocortisolism due to isolated ACTH deficiency were revealed by endocrinological examination. Although not treated, her liver dysfunction and hypothyroid state recovered simultaneously, and the isolated ACTH deficiency was restored six months later. We concluded, after a needle-biopsy of the thyroid, that the transient hypothyroidism was due to Hashimoto's thyroiditis and the reversible ACTH deficiency was probably due to autoimmune hypophysitis. This case shows that cessation of steroid treatment may transiently exacerbate the polyglandular autoimmune syndrome.