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Biomedical subjects

H Takaoka

Publications and source records attributed to H Takaoka.

At least 19 recordsLinked to original sources
PubMed2006

New filarial nematode from Japanese serows (Naemorhedus crispus: Bovidae) close to parasites from elephants.

A new onchocercid species, Loxodontofilaria caprini n. sp. (Filarioidea: Nematoda), found in subcutaneous tissues of 37 (33%) of 112 serows (Noemorhedus crispus) examined in Japan, is described. The female worm had the characteristics of Loxodontofilaria, e.g., the large body size, well-developed esophagus with a shallow buccal cavity, and the long tail with three caudal lappets. The male worm of the new species, which was first described in the genus, had unequal length of spicules, 10 pairs of pre- and post-caudal papillae, and three terminal caudal lappets. Deirids were present in both sexes. Among four species of the genus loxodontofiloria: one from the hippopotamus and three from the Elepantidae, L. caprini n. sp. appears close to L. asiatica Bain, Baker & Chabaud, 1982, a subcutaneous parasite of Elephas indicus in Myanmar (Burma). However, L. caprini n. sp. is distinct from L. asiatica in that the Japanese female worm has an esophagus half as long and the microfilariae also half as long with a coiled posterior. The microfilariae were found in the skin of serows. The new parasite appears to clearly illustrate a major event in the evolution of onchocercids: the host-switching. This might have occurred on the Eurasian continent, where elephantids and the lineage of rupicaprines diversified during the Pliocene-Pleistocene, or in Japan, into which some of these hosts migrated.

Animals↗
PubMed2004

Affinities between Cutifilaria (Nematoda: Filarioidea), parasites of deer, and Mansonella as seen in a new onchocercid, M. (C.) perforata n. sp., from Japan.

A new dermal filarioid nematode, collected from Cervus nippon nippon (sika deer) on Kyushu Island, Japan, showed close affinities between the genera Cutifilaria and Mansonella (Onchocercidae: Onchocercinae): no buccal capsule, esophagus reduced to a thin fibrous tube, and female tail with four lappets. We propose Cutifilaria as a subgenus of Mansonella. Cutifilaria was distinguished from the five other subgenera, Mansonella, Tetrapetalonema, Esslingeria, Sandnema, and Tupainema, in having an area rugosa composed of transverse bands with tiny points, 14-16 papillae around the cloacal aperture, two prominent rhomboidal subterminal papillae, and a thick right spicule with spoon-shaped distal extremity. The host range of Mansonella was extended to ungulates by the addition of Cutifilaria, which appears to be derived from Tupainema, parasitic in Tupaioidea (insectivores), because of the similarity in their right spicules; Cutifilaria seems to have an Asiatic origin. M. (C.) perforata n. sp. was distinct from the sole other related species, M. (C.) wenki, a parasite of Cervus elaphus (red deer) in Europe, having a more complex right spicule with a sturdy terminal point and microfilariae with a bifid posterior end. In addition, almost all females had cuticular pores near the vulva, on the ventral line. The prevalence of microfiloriae and adults of M. (C.) perforata in the skin of sika deer was 38% and 21%, respectively.

Animals↗
PubMed2004

Zoonotic onchocerciasis caused by a parasite from wild boar in Oita, Japan. A comprehensive analysis of morphological characteristics of the worms for its diagnosis.

Histological examination of a nodule removed from the back of the hand of a 58-year-old woman from Oita, Kyushu, Japan showed an Onchocerca female sectioned through the posterior region of the worm (ovaries identifiable) and young (thin cuticle). Six Onchocerca species are enzootic in that area: O. gutturosa and O. lienalis in cattle, O. suzukii in serows (Capricornis crispus), O. skrjabini and an Onchocerca sp. in Cervus nippon nippon, and O. dewittei japonica in wild boar (Sus scrofa leucomystax). Diagnostic characters of female Onchocerca species, such as the cuticle and its ridges, change along the body length. Tables of the histologic morphology of the mid- and posterior body-regions of the local species are presented. In addition, it was observed that transverse ridges arose and thickened during the adult stage (examination of fourth stage and juvenile females of O. volvulus). The specimen described in this report, with its prominent and widely spaced ridges, was identified as O. d. japonica. Four of the 10 zoonotic cases of onchocerciasis reported worldwide were from Oita, three of them being caused by O. d. japonica, the prevalence of which in local wild boar was 22 of 24 (92%).

Animals↗
PubMed2003

Novel functional imaging technique from brain surface with optical coherence tomography enabling visualization of depth resolved functional structure in vivo.

Mapping of the activity of brain by optical intrinsic signal imaging (OISI) provides a two-dimensional activation pattern of visual cortical areas at a resolution of a few hundred microns. However, integration of the intrinsic signal over depth results in loss of finer information about functional organization across the depth. Here, we report the first successful implementation of optical coherence tomography (OCT) at around 30 microm depth resolution to investigate cortical functions of a cat brain in vivo. This technique, named functional OCT (fOCT) provided visually evoked changes in the OCT signal. The fOCT signal shows stimulus specificity that correlates well with that of the intrinsic signals and provides depth resolved layer specific functional information.

Animals↗
PubMed2003

Black flies (Diptera: Simuliidae) attracted to humans and water buffalos and natural infections with filarial larvae, probably Onchocerca sp., in northern Thailand.

Several Simulium species were investigated as to their biting habits and natural infections with filarial larvae at Ban Pan Fan, Chiang Mai Province, in northern Thailand. Female adults flies landing on or flighting around a human and a water buffalo were collected during the daytime from 06.00 to 19.00 hours on 22 June 2001. As a result, 217 S. nodosum, 86 S. asakoae and two S. nigrogilvum were obtained from a human attractant, and 416 S. nodosum, 25 S. nakhonense, 16 S. asakoae, four S. fenestratum and two S. nigrogilvum, from a water buffalo. The blood-feeding was confirmed only for S. nodosum and S. nigrogilvum on humans, and for S. nodosum and S. nakhonense on water buffalos. Dissections of these simuliids showed that S. nodosum was naturally infected with developing filarial larvae. Two types of microfilariae were distinguished but only one type of infective larvae. These larvae resembled Onchocerca suzukii, a parasite from a wild Japanese bovid, suggesting that an unknown Onchocerca species from ruminants was transmitted in Thailand. Infection rates with all stages of larvae and third-stage larvae were 2.3% (14/608) and 1.0% (6/608), respectively. This is the first report of natural infections of black flies with Onchocerca larvae in Southeast Asia, and the involved black fly species is shown to be not only anthropophilic but also zoophilic in this region.

Animals↗
PubMed2002

Diversification of Cercopithifilaria species (Nematoda: Filarioidea) in Japanese wild ruminants with description of two new species.

Twelve of the 17 Cervus nippon nippon deer from Kyushu Island, Japan, that we examined were infected with one or two Cercopithifilaria species. C. longa n. sp. adults were in the subcutaneous tissues of limbs and the abdomen, and C. crassa n. sp. adults were in the skin, mainly in the anterior part of the back; the distribution of the dermal microfilariae generally matched that of the adult worms. The two new species were assigned to the group of primitive Cercopithifilaria species that parasitize ruminants (bavids and cervids), but the new species could readily be distinguished from others morphologically. C. longa was more primitive and resembled C. bulboidea, one of the five species from the serow Capricornis crispus, a Japanese member of the Caprinae, and species from Bovidae in Africa. C. crassa had a thick body and large spicules like C. rugosicauda from Capreolus capreolus in Europe, the only previously known Cercopithifilaria species from cervids, but it also had one or two hypertrophied pairs of caudal papillae, an unusual character found so far only in Japanese parasites. Among the 12 species known from ruminants, four are African, one is European and more highly evolved, and seven are Japanese, with some being primitive and some more evolved. The great diversity of Cercopithifilaria species in the two wild ruminants that live in Japan seems to have resulted from local speciation, which occurred during the Pleistocene, from a primitive form of the C. longa type derived from Eurasiatic ancestors, which has disappeared or, more probably, not yet been discovered.

Animals↗
PubMed2001

Augmentation of cardiac contractility mediated by the human beta(3)-adrenergic receptor overexpressed in the hearts of transgenic mice.

BACKGROUND: Stimulation of beta(1)- and beta(2)-adrenergic receptors (ARs) in the heart results in positive inotropy. In contrast, it has been reported that the beta(3)AR is also expressed in the human heart and that its stimulation leads to negative inotropic effects. METHODS AND RESULTS: To better understand the role of beta(3)ARs in cardiac function, we generated transgenic mice with cardiac-specific overexpression of 330 fmol/mg protein of the human beta(3)AR (TGbeta(3) mice). Hemodynamic characterization was performed by cardiac catheterization in closed-chest anesthetized mice, by pressure-volume-loop analysis, and by echocardiography in conscious mice. After propranolol blockade of endogenous beta(1)- and beta(2)ARs, isoproterenol resulted in an increase in contractility in the TGbeta(3) mice (30%), with no effect in wild-type mice. Similarly, stimulation with the selective human beta(3)AR agonist L-755,507 significantly increased contractility in the TGbeta(3) mice (160%), with no effect in wild-type mice, as determined by hemodynamic measurements and by end-systolic pressure-volume relations. The underlying mechanism of the positive inotropy incurred with L-755,507 in the TGbeta(3) mice was investigated in terms of beta(3)AR-G-protein coupling and adenylyl cyclase activation. Stimulation of cardiac membranes from TGbeta(3) mice with L-755,507 resulted in a pertussis toxin-insensitive 1.33-fold increase in [(35)S]GTPgammaS loading and a 1.6-fold increase in adenylyl cyclase activity. CONCLUSIONS: Cardiac overexpression of human beta(3)ARs results in positive inotropy only on stimulation with a beta(3)AR agonist. Overexpressed beta(3)ARs couple to G(s) and activate adenylyl cyclase on agonist stimulation.

Adenylyl Cyclases↗
PubMed2001

Cloning and characterization of adenylate kinase from Chlamydia pneumoniae.

Chlamydiae proliferate only within the infected host cells and are thought to be "energy parasites," because they take up ATP from the host cell as an energy source. In the present study, we isolated from Chlamydia pneumoniae the gene encoding adenylate kinase (AK). Using the enzyme produced in Escherichia coli, its properties were characterized. K(m) values for AMP and for ADP of the purified C. pneumoniae AK (AKcpn) were each 330 microm, which is significantly higher than the reported values of other AKs, whereas K(m) for ATP was 24 microm, which was rather lower than others. AKcpn contains 1 g atom of zinc/mol of 24,000-dalton protein. Mass spectrometric analysis of AKcpn and analysis of properties of mutated AKcpn strongly suggested that zinc is associated with four cysteine residues in the LID domain of the enzyme. The apo-AKcpn that lost zinc retained AK activity, although K(m) for AMP of apo-AKcpn increased about 2-fold and V(max) decreased about one-half from that of holo-AKcpn. The apo-AKcpn was more thermolabile and sensitive to trypsin digestion than the holo-AKcpn. Moreover, the recovery in vitro of the AK activity during the renaturation process of the denatured apo-AKcpn was dependent on zinc. A mutated protein in which cysteine residues in the LID domain were substituted by other amino acids lost both zinc and enzyme activity. The mutated protein was more sensitive to protease than the apo-AKcpn. These results indicate that zinc in AKcpn, although not essential for the catalysis, stabilizes the enzyme and probably plays a crucial role in proper folding of the protein. Furthermore, the catalytic properties of AKcpn suggest a distinctive regulatory mechanism in the metabolism compared with AKs in other organisms.

Adenylate Kinase↗
PubMed2001

Coexistence of five Cercopithifilaria species in the Japanese rupicaprine bovid, Capricornis crispus.

The Japanese serow, Capricornis crispus (Bovidae, Caprinae, Rupicaprini), is parasitized by five Cercopithifilaria species: C. shohoi, recently described, and reexamined in this paper, C. multicauda n. sp., C. minuta n. sp., C. tumidicervicata n. sp., and C. bulboidea n. sp. Coinfections are frequent. The location (skin or subcutaneous regions) in the host of adult worms differed between the species, as did many morphological characters of both adults and microfilariae. The location (limbs, trunk, etc.) in the host of adult worms and dermal microfilariae seemed to differ depending on the species. Male and female worms of the same species had similar head shapes, buccal capsules, and, in four species, swellings in the anterior region of the body (because of the presence of a giant ventral pseudocoelomocyte). The Cercopithifilaria spp. from C. crispus were related to the primitive forms of the genus, parasites of Bovidae and Cervidae, presently recorded in Africa and Europe. C. bulboidea was particularly close to the most primitive species, C. ruandae and C. dermicola, in Africa, with the pairs of caudal papillae numbered 8 and 9 being distant from each other, but the species also had several specialized characters. Like C. rugosicauda in a European cervid, the four other species had pairs 8 and 9 close to each other; they reflect an evolutionary trend (hypertrophy of pair 6, and reduction and posterior migration of pair 7) that suggests diversification in the host.

Animals↗
PubMed2001

Onchocerca dewittei japonica n. subsp., a common parasite from wild boar in Kyushu Island, Japan.

We describe Onchocerca dewittei japonica n. subsp. from the Japanese wild boar, Sus scrofa leucomystax, in Oita, Kyushu Island, where all seven animals examined were found to be infected. This study began with efforts to identify the causative species in a recent case of zoonotic onchocerciasis. Compared with Onchocerca dewittei dewittei from Sus scrofa jubatus in Malaysia, which was reexamined here, our new subspecies has much greater space between the ridges on the females. In addition, its microfilariae (from uteri) are shorter (192-210 microns compared with 228-247 microns), and only the posterior third of the microfilarial body is coiled, instead of the entire body. The Onchocerca species parasitic in suids (these two subspecies and O. ramachandrini from the warthog in the Ethiopian region) form a group sharing several characters. Among the most unusual characters are the body swellings (a specialized apparatus for mating, known in only a few other genera). In addition, longitudinal cuticular crests were found on males of both subspecies from wild boar and on females of O. ramachandrini.

Animals↗
PubMed2001

Plasma brain natriuretic peptide as a novel therapeutic indicator in idiopathic dilated cardiomyopathy during beta-blocker therapy: a potential of hormone-guided treatment.

BACKGROUND: Plasma brain natriuretic peptide (BNP) is a sensitive and specific marker of left ventricular (LV) function. In the treatment of heart failure, especially in idiopathic dilated cardiomyopathy (IDC), beta-blocker (BB) therapy has been established as a powerful strategy. The purpose of this study was to analyze relationships between changes in BNP level and LV function during BB therapy in patients with IDC. METHODS: In 30 patients with IDC who had already received conventional therapy, measurement for plasma BNP and norepinephrine levels and echocardiographic indices were evaluated before and 2 and 6 months after carvedilol in 21 patients and at baseline and after 6 months in 9 patients who did not receive carvedilol. RESULTS: After 6 months carvedilol treatment significantly improved LV end-diastolic dimension (LVEDD) (65 +/- 8 to 61 +/- 8 mm) and LV ejection fraction (LVEF) (34% +/- 13% to 43% +/- 12%) with intergroup differences; it significantly decreased BNP (127 +/- 113 to 69 +/- 92 pg/mL) with no intergroup difference; however, it did not decrease norepinephrine. BNP correlated strongly with LVEDD, LVEF, and LV mass index in carvedilol-treated patients. The degree of change in BNP correlated with that in LVEDD or LVEF 6 months after carvedilol. All 14 patients with decreased or unchanged BNP levels showed an increase in LVEF, and 4 of 7 with a rise in BNP had decreased or unchanged LVEF. According to receiver operating characteristic analysis, the optimal BNP levels for detecting LVEF <35% before and after carvedilol were 75.5 and 69 pg/mL, respectively. CONCLUSION: Plasma BNP levels may accurately reflect alteration in LV function and structure and can be used as a therapeutic indicator for risk stratification in patients with IDC during BB therapy.

Adrenergic beta-Antagonists↗
PubMed2001

Detection of Orientia tsutsugamushi (Rickettsiales: rickettsiaceae) in unengorged chiggers (Acari: Trombiculidae) from Oita Prefecture, Japan, by nested polymerase chain reaction.

The current study surveyed the 56-kDa type-specific antigen (TSA) gene DNAs of Orientia tsutsugamushi (Hayashi) in approximately 4.000 unengorged chiggers obtained from the soil or ground surface in an endemic and a nonendemic area of the Tsutsugamushi disease in Oita Prefecture, southwestern Japan, by nested polymerase chain reaction (PCR). Serotypes of O. tsutsugamushi were identified by restriction fragment-length polymorphism (RFLP) analysis. In the endemic area, 242 pools from five species [234 pools of Leptotrombidium scutellare (Nagayo, Miyagawa, Mitamura, Tamiya and Tenjin), two L. pallidum (Nagayo, Miyagawa, Mitamura and Tamiya), four L. kitasatoi (Fukuzumi & Obata), one L. fuji (Kuwata, Berge and Philip), and one Neotrombicula japonica (Tanaka, Kaiwa, Teramura and Kagaya)] were tested, and eight (seven pools of L. scutellare and one N. japonica) were positive for O. tsutsugamushi. Among the seven positive pools of L. scutellare, the distribution of serotypes was as follows: Kuroki (4), Gilliam (1), Karp (1), and Kawasaki (1). The first two serotypes (Kuroki and Gilliam) were identified for the first time in this species. In the nonendemic area, 128 pools from eight species were tested, and 13 were positive for O. tsutsugamushi. The positive rate was as follows: L. pallidum (4/41). L. kitasatoi (1/18), Gahrliepia saduski Womersley (2/10), L. fuji (4/50), L. himizu (Sasa, Kumada, Hayashi, Enomoto, Fukuzumi and Obata) (1/2), and Miyatrombicula kochiensis (Sasa, Kawashima and Egashira) (1/3). The latter three species were shown for the first time to harbor O. tsutsugamushi. All ofthe positive pools were Kuroki, except for two pools (one L. pallidum and one L. fuji), which were Gilliam (this serotype was also detected for the first time in L. pallidum). Further analysis revealed no differences in the nucleotide sequences (125 bp of variable domain 1 of TSA gene) of the same serotypes (i.e., Kuroki and Gilliam) among the positive samples. These data indicate that O. tsutsugamushi was widely distributed in various trombiculid species, even in the nonendemic area. The data are also suggestive of a possible horizontal transmission of O. tsutsugamushi among trombiculid species.

Animals↗
PubMed2001

[Nitric oxide spares myocardial oxygen consumption through attenuation of contractile response to beta-adrenergic stimulation in patients with idiopathic dilated cardiomyopathy].

BACKGROUND: The results of recent studies suggest that nitric oxide (NO) synthase may increase in the failing myocardium and that NO modulates the myocardial contractile response to beta-adrenergic stimulation. However, there are few data regarding the physiological role of NO in patients with heart failure. The aim of the present study was to address the role of NO in left ventricular contractile response to beta-adrenergic stimulation and corresponding oxygen expenditure in human heart failure. METHODS AND RESULTS: We studied 15 patients with heart failure due to idiopathic dilated cardiomyopathy (mean ejection fraction 0.33). We examined left ventricular contractility (Emax, the slope of end-systolic pressure-volume relation), left ventricular external work (EW), myocardial oxygen consumption (MVO2), and mechanical efficiency (measured as EW/MVO2) with the use of conductance and coronary sinus thermodilution catheters before and during dobutamine (DOB) infusion via a peripheral vein (4.8 +/- 0.3 micrograms.kg-1.min-1 i.v.). Heart rate was kept constant with atrial pacing. We carried out a similar protocol during the intracoronary infusion of the NO synthase inhibitor NG-monomethyl-L-arginine (L-NMMA; 200 mumol). DOB increased Emax, EW, and MVO2 (by 77 +/- 17%, 39 +/- 5%, and 21 +/- 5%, respectively), leading to an increase in mechanical efficiency (25.4 +/- 3.1% to 29.6 +/- 4.1%). L-NMMA alone did not significantly change these variables. Although the concurrent infusion of DOB with L-NMMA increased Emax, EW, and MVO2 (by 140 +/- 21%, 64 +/- 9%, and 35 +/- 5%, respectively) more than DOB alone, mechanical efficiency did not increase further (24.3 +/- 3.3% to 29.5 +/- 4.5%) because EW and MVO2 increased in parallel. CONCLUSIONS: These data suggest that in patients with idiopathic dilated cardiomyopathy, endogenous NO spares MVO2 through attenuation of left ventricular contractile response to beta-adrenergic stimulation while maintaining left ventricular energy-converting efficiency.

Cardiomyopathy, Dilated↗
PubMed2001

Distribution of unengorged larvae of Leptotrombidium pallidum and other species in and around the rodent nest holes.

The distribution of unengorged larvae of Leptotrombidium pallidum, L. fuji and L. kitasatoi in and around 12 rodent-nest holes in Oita Prefecture, Japan was studied using the Tullgren funnel apparatus. Soil was taken from each nest hole, and the ground-surface soil and litter from the surrounding area A (an inner quadrate of 20 cm x 20 cm except the nest hole), and also from the outer area B (an outer quadrate of 40 cm x 40 cm excluding A and the nest hole) were sampled, separately. The numbers (% of the total) of L. pallidum collected from soil samples of the nest holes and areas A and B were 38 (19.0), 111 (55.5) and 30 (15.0); those of L. fuji were 171 (58.8), 104 (35.7) and 14 (4.8); those of L. kitasatoi were 35 (77.9), 7 (15.6) and 3 (6.7), and those of G. saduski were 20 (50.0), 17 (42.5) and 3 (7.5). The larvae recovered from litter samples were few, representing 0-8.5% of the total. It is shown that unengorged larvae of these species are distributed not only in the nest holes but also in the nearby areas, and exist mainly on (or in) the soil.

Animals↗
PubMed2000

Nitric oxide spares myocardial oxygen consumption through attenuation of contractile response to beta-adrenergic stimulation in patients with idiopathic dilated cardiomyopathy.

BACKGROUND: The results of recent studies suggest that NO synthase may increase in the failing myocardium and that NO modulates the myocardial contractile response to beta-adrenergic stimulation. However, there are few data regarding the physiological role of NO in patients with heart failure. The aim of the present study was to address the role of NO in left ventricular (LV) contractile response to beta-adrenergic stimulation and corresponding oxygen expenditure in human heart failure. METHODS AND RESULTS: We studied 15 patients with heart failure due to idiopathic dilated cardiomyopathy (mean ejection fraction 0.33). We examined LV contractility (E(max), the slope of end-systolic pressure-volume relation), LV external work (EW), myocardial oxygen consumption (MVO(2)), and mechanical efficiency (measured as EW/MVO(2)) with the use of conductance and coronary sinus thermodilution catheters before and during dobutamine (DOB) infusion via a peripheral vein (4. 8+/-0.3 microg. kg(-1). min(-1) IV). Heart rate was kept constant with atrial pacing. We carried out a similar protocol during the intracoronary infusion of the NO synthase inhibitor N(G)-monomethyl-L-arginine (L-NMMA; 200 micromol). DOB increased E(max), EW, and MVO(2) (by 77+/-17%, 39+/-5%, and 21+/-5%, respectively), leading to an increase in mechanical efficiency (25.4+/-3.1% to 29.6+/-4.1%). L-NMMA alone did not significantly change these variables. Although the concurrent infusion of DOB with L-NMMA increased E(max), EW, and MVO(2) (by 140+/-21%, 64+/-9%, and 35+/-5%, respectively) more than DOB alone, mechanical efficiency did not increase further (24.3+/-3.3% to 29.5+/-4.5%) because EW and MVO(2) increased in parallel. Conclusions-These data suggest that in patients with idiopathic dilated cardiomyopathy, endogenous NO spares MVO(2) through attenuation of LV contractile response to beta-adrenergic stimulation while maintaining LV energy-converting efficiency.

Adrenergic beta-Agonists↗
PubMed2000

Effect of beta-blocker therapy on severe ventricular arrhythmias in patients with idiopathic dilated cardiomyopathy.

Beta-blocker therapy has been shown to improve cardiac function and prognosis in patients with idiopathic dilated cardiomyopathy (DCM). However, whether beta-blockers reduce severe ventricular arrhythmias and sudden cardiac death has not been clarified. The present study was designed to investigate the effects of beta-blockers on non-sustained ventricular tachycardia (VT) and sudden cardiac death in patients with DCM. Sixty-five patients with DCM treated with diuretics, digitalis and angiotensin-converting enzyme inhibitors were assigned to receive beta-blockers (n = 33) or not (n = 32). Mean follow-up was 53+/-30 months. The echocardiographic indices of cardiac function, the incidence of non-sustained VT on Holter monitoring electrocardiograms, and sudden cardiac death rate were compared between the 2 groups. Comparable improvement in cardiac function on echocardiograms was found in the 2 treatment groups. The patient group treated with beta-blockers showed a significant reduction in the prevalence of VT (from 43 to 15%, p<0.05) and the development of new episodes of VT (5 vs. 16%) compared to the group without beta-blockers. The sudden cardiac death rate did not differ between the 2 groups. The results of the present study suggest that beta-blockers are effective in reducing severe ventricular arrhythmias in patients with DCM.

Adrenergic beta-Antagonists↗
PubMed1999

Systemic endothelial function is preserved in men with both active and inactive variant angina pectoris.

To test the hypothesis that coronary spasm could be a coronary manifestation of systemic endothelial dysfunction and that the activity of coronary spasm could influence systemic endothelial function, we examined brachial flow-mediated, endothelium-dependent vasodilation and nitroglycerin-induced endothelium-independent vasodilation with high-resolution ultrasound in 11 men with variant angina pectoris (6 active and 5 inactive) without established coronary atherosclerosis. Endothelium-dependent vasodilation in peripheral circulation was preserved in men with active and inactive variant angina pectoris, suggesting that systemic endothelial dysfunction is not involved in either the pathogenesis or the activity of coronary spasm.

Aged↗