Life-Long Wheel Running Attenuates Age-Related Fiber Loss in the Plantaris Muscle of Mice: a Pilot Study.

The purpose of this study was to investigate whether long-term wheel running would attenuate age-related loss of muscle fiber. Male ICR mice were divided into young (Y, n=12, aged 3 months), old-sedentary (OS, n=5, aged 24 months), and old-exercise (OE, n=6, aged 24 months) groups. The OE group started spontaneous wheel running at 3 months and continued until 24 months of age. Soleus and plantaris muscles were fixed in 4% paraformaldehyde buffer. The fixed muscle was digested in a 50% NaOH solution to isolate single fiber and then fiber number was quantified. The masses of the soleus and plantaris muscles were significantly lower at 24 months than at 3 months of age, and this age-related difference was attenuated by wheel running (P<0.05). Soleus muscle fiber number did not differ among the groups. In the plantaris muscle, the fiber number in the OS group (1 288±92 fibers) was significantly lower than in the Y group (1 874±93 fibers), and this decrease was attenuated in the OE group (1 591±80 fibers) (P<0.05). These results suggest that age-related fiber loss occurs only in the fast-twitch fiber-rich muscle of mice, and that life-long wheel running exercise can prevent this fiber loss.

Applications of magnetic and electromagnetic forces in micro-analytical systems.

Novel applications of magnetic fields in analytical chemistry have become a remarkable trend in the last two decades. Various magnetic forces have been employed for the migration, orientation, manipulation, and trapping of microparticles, and new analytical platforms for separating and detecting molecules have been proposed. Magnetic materials such as functional magnetic nanoparticles, magnetic nanocomposites, and specially designed magnetic solids and liquids have also been developed for analytical purposes. Numerous attractive applications of magnetic and electromagnetic forces on magnetic and non-magnetic materials have been studied, but fundamental studies to understand the working principles of magnetic forces have been challenging. These studies will form a new field of magneto-analytical science, which should be developed as an interdisciplinary field. In this review, essential pioneering works and recent attractive developments are presented.

Brain-derived neurotrophic factor treatment increases the skeletal muscle glucose transporter 4 protein expression in mice.

The purpose of the present study was to investigate whether peripheral brain-derived neurotrophic factor (BDNF) treatment induced metabolic adaptations in mouse skeletal muscle. BDNF (20 mg/kg/day) was injected subcutaneously for successive 14 days. BDNF treatment significantly reduced the total food intake and inhibited the weight gain in comparison to the control group. The glucose transporter 4 (GLUT4) protein expression in the gastrocnemius muscle was significantly increased by BDNF treatment in comparison to the control and pair-fed groups. Neither the oxidative nor the glycolytic enzyme activities in the gastrocnemius muscle changed after the BDNF treatment. These results suggest that the peripheral BDNF treatment promotes the skeletal muscle GLUT4 protein expression as well as hypophagia.

HUNT: launch of a full-length cDNA database from the Helix Research Institute.

The Helix Research Institute (HRI) in Japan is releasing 4356 HUman Novel Transcripts and related information in the newly established HUNT database. The institute is a joint research project principally funded by the Japanese Ministry of International Trade and Industry, and the clones were sequenced in the governmental New Energy and Industrial Technology Development Organization (NEDO) Human cDNA Sequencing Project. The HUNT database contains an extensive amount of annotation from advanced analysis and represents an essential bioinformatics contribution towards understanding of the gene function. The HRI human cDNA clones were obtained from full-length enriched cDNA libraries constructed with the oligo-capping method and have resulted in novel full-length cDNA sequences. A large fraction has little similarity to any proteins of known function and to obtain clues about possible function we have developed original analysis procedures. Any putative function deduced here can be validated or refuted by complementary analysis results. The user can also extract information from specific categories like PROSITE patterns, PFAM domains, PSORT localization, transmembrane helices and clones with GENIUS structure assignments. The HUNT database can be accessed at http://www.hri.co.jp/HUNT.

Study on risk management of heavy metals for reuse of biosolids.

The behaviour of heavy metals was investigated at 22 wastewater treatment plants (WWTPs). In addition, the survey of heavy metal balance was conducted in detail at one WWTP. For the measurement, 22 types of heavy metals were selected from the chemical materials of pollutant release and transfer register (PRTR). There were some heavy metals, which were detected not in wastewater but in dewatered sludge. By means of the detailed survey at one WWTP, 60 to 80% of some heavy metals, such as B, Mn, Co, Ni and Mo, were discharged with treated water. According to the results of PRTR, Zn, B and Mn accounted for a large part of the discharge into the water course. To estimate the behaviour of heavy metals in the environment, leaching tests were applied to the products made of biosolids. During a series of leaching tests for building materials, it was observed that the concentration of heavy metals was very small, but the ratio of increase keeps a constant value. Therefore, it was considered that the acid extractable contents of heavy metal would be important.

Prevalence of the coexistence of left ventricular false tendons and premature ventricular complexes in apparently healthy subjects: a prospective study in the general population.

The prevalence of left ventricular false tendons, premature ventricular complexes and their coexistence was evaluated prospectively in 187 healthy company workers aged 21 to 50 (mean 36) years. False tendons were demonstrated echocardiographically in 133 (71%). Eight subjects were withdrawn from the study because of silent mitral valve prolapse. In these 179 healthy subjects, false tendons were detected in 127 (71%) and premature ventricular complexes in 48 (27%). Their coexistence was observed in 40, which showed a significant correlation (p less than 0.05) of false tendons and premature ventricular complexes. In seven of the eight subjects without false tendons, premature ventricular complexes were uniform and infrequent (mean 3 beats/24 h). In the 40 subjects with false tendons, premature ventricular complexes were uniform in 29, multiform in 6 and repetitive in 5, and the mean frequency was 96 beats/24 h. Correlation of premature ventricular complexes with the type of false tendons showed that premature ventricular complexes were significantly associated with thick (greater than or equal to 2 mm) and longitudinal tendons (p less than 0.005). Although it is not certain that left ventricular false tendons are arrhythmogenic, the prevalence of the coexistence of left ventricular false tendons and premature ventricular complexes in the general population, and the special relation between the frequency and the form of premature ventricular complexes and the type of false tendons, suggests that false tendons may play an etiologic role in the genesis of premature ventricular complexes in apparently healthy subjects.

Genome analysis: Assigning protein coding regions to three-dimensional structures.

We describe the results of a procedure for maximizing the number of sequences that can be reliably linked to a protein of known three-dimensional structure. Unlike other methods, which try to increase sensitivity through the use of fold recognition software, we only use conventional sequence alignment tools, but apply them in a manner that significantly increases the number of relationships detected. We analyzed 11 genomes and found that, depending on the genome, between 23 and 32% of the ORFs had significant matches to proteins of known structure. In all cases, the aligned region consisted of either >100 residues or >50% of the smaller sequence. Slightly higher percentages could be attained if smaller motifs were also included. This is significantly higher than most previously reported methods, even those that have a fold-recognition component. We survey the biochemical and structural characteristics of the most frequently occurring proteins, and discuss the extent to which alignment methods can realistically assign function to gene products.

Identification of two polyketide synthase gene clusters on the linear plasmid pSLA2-L in Streptomyces rochei.

The 200kb linear plasmid pSLA2-L was suggested to be involved in the production of two macrolide antibiotics, lankamycin (Lm) and lankacidin (Lc), in Streptomyces rochei 7434AN4. Hybridization experiments with the polyketide synthase (PKS) genes for erythromycin and actinorhodin identified two eryAI-homologous regions and an actI-homologous region on pSLA2-L. The nucleotide sequence of a 3.6kb SacI fragment carrying one of the eryAI-homologs revealed that it codes for part of a large protein with four domains for ketoreductase, acyl carrier protein, ketosynthase, and acyltransferase. Gene disruption confirmed that the two eryAI-homologs are parts of a large type-I PKS gene cluster for Lm. A 4.8kb DNA carrying the actI-homologous region contains four open reading frames (ORF1-ORF4) as well as an additional ORF, i.e. ORF5, which might code for a thioesterase. Deletion of the ORF2-ORF4 region showed that it is not involved in the synthesis of Lm or Lc. Thus, it was confirmed that pSLA2-L contains two PKS gene clusters for Lm and an unknown type-II polyketide.

Improvement in left ventricular diastolic function during intravenous and oral diltiazem therapy in patients with hypertrophic cardiomyopathy: an echocardiographic study.

M-mode echocardiography was used to evaluate the acute effect of intravenously administered diltiazem, 10 mg, and the chronic effects of oral diltiazem, 180 mg/day, and propranolol, 60 to 120 mg/day, administered for 2 weeks on left ventricular (LV) systolic and diastolic function in 13 patients with hypertrophic cardiomyopathy. Intravenous injection of diltiazem reduced isovolumic relaxation time from 114 +/- 26 to 99 +/- 21 ms (p less than 0.01) and the time to peak rate of LV dimensional lengthening from 166 +/- 17 to 133 +/- 10 ms (p less than 0.01), without significant changes of LV dimensions or fractional shortening. No significant changes were observed in LV dimensions or fractional shortening, but a significant increase in peak rate of LV dimensional lengthening (from 4.1 +/- 1.5 to 4.8 +/- 1.6/s, p less than 0.05) and a reduction in isovolumic relaxation time (from 105 +/- 26 to 77 +/- 23 ms, p less than 0.01) and the time to peak rate of LV dimensional lengthening (from 156 +/- 23 to 124 +/- 20 ms, p less than 0.01) occurred during the oral administration of diltiazem. In contrast, propranolol caused no significant changes in these values. Thus, diltiazem improves LV relaxation and diastolic filling without altering LV systolic function in patients with hypertrophic cardiomyopathy.

Noninvasive detection of left ventricular diastolic dysfunction using M-mode echocardiography to assess left ventricular posterior wall kinetics in hypertrophic cardiomyopathy.

In patients with hypertrophic cardiomyopathy (HC), it is difficult to determine the severity of left ventricular (LV) diastolic dysfunction. Three different patterns of LV posterior wall motion were found by M-mode echocardiography in patients with HC, and the use of these patterns is proposed as a new noninvasive index of the severity of LV diastolic dysfunction. M-mode echocardiograms were recorded prospectively from 35 patients with HC, and the posterior wall motion pattern in late systole and early diastole was classified into the following 3 types: (1) normal motion (n = 9); (2) flat motion--flat motion from late systole to early diastole, followed by rapid backward movement (n = 13); and (3) downward motion--slow backward movement from late systole (n = 13). There were no differences in the severity or type of hypertrophy, LV systolic function and pulsed Doppler indexes of LV filling among these 3 groups. However, LV end-diastolic pressure was increased in the groups with flat (15 +/- 6 mm Hg) and downward (16 +/- 9 mm Hg) motion. Furthermore, the maximal rate of decrease in LV pressure (normal 1,450 +/- 300, flat 1,250 +/- 300 and downward 860 +/- 80 mm Hg/s) and the time constant of LV pressure reduction (normal 60 +/- 15, flat 70 +/- 25 and downward 101 +/- 34 ms) showed a stepwise deterioration from the normal to the flat and then to the downward motion groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Natural history and left ventricular response in chronic aortic regurgitation.

This study was aimed at clarifying the natural history and left ventricular response in aortic regurgitation using M-mode echocardiography. We analyzed the history and echocardiographic data on 94 patients, who were divided into 4 stages according to symptoms. The duration of the asymptomatic period, which represents pure volume overload, is long, and the period of minimal symptoms, combined volume and pressure overload, is relatively short. Patients with overt heart failure due to impaired contractility can survive longer than is usually believed, and the factor that predicted the onset of heart failure was a decrease in fractional shortening > 3.8 percentage points.

Influence of warfarin therapy on left atrial spontaneous echo contrast in nonvalvular atrial fibrillation.

To examine whether warfarin therapy had any influence on left atrial spontaneous echo contrast, we performed serial transesophageal echocardiography with integrated backscatter analysis in 12 patients with non-valvular atrial fibrillation. We found that the integrated backscatter intensity of the left atrial cavity did not change after 1 to 2 months of warfarin therapy, and concluded that this therapy does not influence spontaneous echo contrast.

Influence of altered loading conditions on left atrial appendage function in vivo.

This study sought to examine the influence of heart failure treatment on left atrial (LA) appendage function in 10 patients with left ventricular dysfunction. After treatment of heart failure, LA appendage function markedly improved, less dependent on LA and left ventricular functions, which suggests that with altered loading conditions, LA appendage function changes chiefly through its intrinsic contractile property.

The contribution of cardiorespiratory fitness and visceral fat to risk factors in Japanese patients with impaired glucose tolerance and type 2 diabetes mellitus.

It is still unclear as to how cardiorespiratory fitness and visceral fat accumulation contribute to coronary heart disease (CHD) risk factors in patients with diabetes mellitus. The purpose of the present study was to investigate whether cardiorespiratory fitness contributes to such risk factors independently of visceral fat accumulation. Two hundred Japanese patients (137 men and 63 women, aged 22 to 81 years) with impaired glucose tolerance (IGT) and type 2 diabetes mellitus (type 2 DM) without any intervention and pharmacological therapy participated in a cross-sectional study. The levels of fasting insulin, triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and resting blood pressure were assessed. Maximal oxygen uptake (V.o(2max)), an index of cardiorespiratory fitness, was predicted by a graded exercise test using a cycle ergometer. Visceral fat area (VFA) was measured by computed tomography scan. The criteria for abnormalities of the risk factors were determined according to the standard values for Japanese. All subjects were divided equally into the following 3 groups according to their fitness level: low-fit (V.o(2max) < 32 mL/kg/min in men, V.o(2max) < 26 mL/kg/min in women), mid-fit (32 < or = V.o(2max) < 36 in men, 26 < or = V.o(2max) < 30 in women), and high-fit (V.o(2max) > or = 36 in men, V.o(2max) > or = 30 in women). The association between fitness level and the prevalence of abnormal values for these parameters was analyzed by a multiple logistic regression model adjusted for age and VFA. The odds ratio (OR) and 95% confidence interval (CI) for the prevalence of hyperinsulinemia were significantly lower in the mid-fit (OR = 0.35, 95% CI, 0.16 to 0.78) and in the high-fit groups (OR = 0.40, 95% CI, 0.16 to 0.98) compared with the low-fit group. In addition, ORs for the prevalence of low HDL-C in the mid-fit and high-fit groups were significantly lower (OR = 0.35, 95% CI, 0.14 to 0.86; and OR = 0.19; 95% CI, 0.08 to 0.60, respectively) than in the low-fit group. These results suggested that cardiorespiratory fitness might be one of the predictors of metabolic abnormalities, especially in patients with hyperinsulinemia and low HDL-C, independent of visceral fat accumulation in Japanese patients with IGT and type 2 DM.

Ratio of pulmonary venous to mitral A velocity is a useful marker for predicting mean pulmonary capillary wedge pressure in patients with left ventricular systolic dysfunction.

In patients with an elevated left ventricular filling pressure, the mitral A wave is diminished while the pulmonary venous A wave is augmented because of decreased left ventricular compliance. We examined whether an increase in the ratio of pulmonary venous to mitral A velocity might be a marker for an elevated mean pulmonary capillary wedge pressure. Forty-one patients who had left ventricular systolic dysfunction underwent transthoracic Doppler echocardiography simultaneously or within 24 hours of right heart catheterization. There were 29 men and 12 women 61 +/- 12 (mean +/- SD) years of age. Underlying heart disease was ischemic cardiomyopathy in 27 and nonischemic cardiomyopathy in 14 patients. The same Doppler-hemodynamic study was performed on 8 patients after optimal management of heart failure. The ratio of pulmonary venous to mitral A velocity correlated strongly with mean pulmonary wedge pressure (r = 0.72, P < .0001). When the cutoff value of the ratio was set at 0.5 or higher, the sensitivity for predicting a pulmonary capillary wedge pressure of 15 mm Hg or more was 88%, and the specificity was 80%. The serial Doppler-hemodynamic study showed that the ratio decreased markedly after treatment of heart failure. The value was 0.84 +/- 0.29 before treatment and 0.36 +/- 0.17 after treatment (P = .001). An increased ratio of pulmonary venous to mitral A velocity is a useful marker for elevated pulmonary capillary wedge pressure among patients with left ventricular systolic dysfunction.

Left ventricular Doppler filling pattern in dilated cardiomyopathy: relation to hemodynamics and left atrial function.

This study attempted to examine the relation of left ventricular filling patterns to hemodynamic status and left atrial function in dilated cardiomyopathy. Transesophageal echocardiography and cardiac catheterization were performed in 41 patients with dilated cardiomyopathy (six with an ischemic origin). Transmitral, left atrial appendage, and pulmonary venous flow velocities were recorded with the pulsed Doppler method. Left atrial systolic function was assessed by the peak velocity of the left atrial appendage emptying wave and pulmonary venous flow reversal during atrial systole. Patients were classified into three groups according to their left ventricular filling patterns. Group 1 showed an abnormal relaxation pattern (E wave/A wave ratio <1, n = 17), group 2 had a normal or pseudonormal pattern (1 < or = E/A < 2, n = 11), and group 3 had a restrictive pattern (E/A > or = 2, n = 13). No differences were found among the groups with regard to age, gender, heart rate, and M-mode echocardiographic indices of left ventricular function. Compared with patients in group 1, those in groups 2 and 3 had more symptoms (New York Heart Association functional class III or IV) and had higher left ventricular filling pressures. The sensitivity of an E/A ratio > or = 1 for predicting a pulmonary capillary wedge pressure > or = 15 mm Hg was 75% and the specificity was 94%. Despite a similar increase of filling pressures, group 3 patients had a lower left atrial appendage emptying velocity, pulmonary venous flow reversal velocity, and mitral A velocity than did group 2 patients. The sensitivity and specificity of an E/A ratio > or = 22 for detecting left atrial dysfunction (left atrial appendage emptying velocity < or = 40 cm/sec) was 85% and 86%, respectively. In conclusion, among patients with dilated cardiomyopathy, those who had a restrictive or pseudonormal filling pattern were in a higher functional class and had higher filling pressures. Further studies are needed to determine the therapeutic and prognostic significance of left atrial dysfunction, which was common in patients with a restrictive pattern.

Integrated backscatter assessment of left atrial spontaneous echo contrast in chronic nonvalvular atrial fibrillation: relation with clinical and echocardiographic parameters.

Integrated backscatter (IB) provides the quantitative assessment of left atrial spontaneous echo contrast (SEC). The IB intensity of the left atrial cavity relative to the left ventricular cavity is related to atrial thrombus in patients with atrial fibrillation (AF) or sinus rhythm. However, little is known about the relation between the quantitative SEC value of the left atrial cavity and variables implying thromboembolism in nonvalvular AF. To examine this relation, we performed transesophageal echo-cardiography with IB analysis in 65 patients with chronic nonvalvular AF. The quantitative SEC value of the left atrial cavity was defined as the difference between atrial IB intensity and ventricular IB intensity (corrected IB intensity). The corrected IB intensity was correlated with the left atrial dimension (r = 0.25, P =.049), the left atrial appendage velocity (r = -0.41, P <.001), and the duration of AF (r = 0.23, P =. 023). The corrected IB intensity was higher in patients who had a history of hypertension (3.2 +/- 2.2 dB versus 2.0 +/- 1.6 dB, P =. 018), SEC (3.9 +/- 1.9 dB versus 1.4 +/- 1.1 dB, P =.002), and left atrial thrombus (4.5 +/- 2.7 dB versus 2.2 +/- 1.7 dB, P <.001) when compared with those who did not have these abnormalities. The corrected IB intensity was significantly lower in patients with significant mitral regurgitation than in those without it (1.1 +/- 1. 2 dB versus 2.7 +/- 2.0 dB, P =.036). When the cutoff value of the corrected IB intensity was set at >/=2.0 dB, the sensitivity for left atrial thrombus was 78% and the specificity was 55%. In patients with chronic nonvalvular AF, the quantitative SEC value of the left atrial cavity depends on the duration of AF as well as the left atrial dimension and appendage velocity. Although IB may be capable of identifying patients with higher risk of cardiogenic embolism, a large-scale prospective study is needed to actually establish this.

Reversible left atrial dysfunction possibly due to afterload mismatch in patients with left ventricular dysfunction.

Limited data are available concerning the influence of altered loading conditions on left atrial (LA) function. In addition, the underlying mechanism of the augmentation of atrial filling (A) velocity (assessed by transmitral Doppler measurement) after treatment of heart failure has been less studied. Therefore, we examined various indexes of LA function during the depression of left ventricular (LV) filling pressure resulting from treatment of heart failure. Twelve patients with LV dysfunction (ejection fraction < 50%) underwent right heart catheterization and transthoracic echocardiography before and after optimal treatment of heart failure. LV/LA volume and ejection fraction and mitral and pulmonary venous flow velocities were measured. LV stiffness (substitute for LA afterload) was assessed by the ratio of LV filling pressure to LV end-diastolic volume. After treatment of heart failure, the mitral A velocity significantly increased (38 +/- 9 to 58 +/- 16 cm/sec, p < 0.005) and there was a distinct attenuation of the difference of the pulmonary venous and mitral A-wave duration (43 +/- 29 to -8 +/- 31 msec, p < 0.005). These findings were associated with a marked decrease in LV stiffness (0.12 +/- 0.04 to 0.05 +/- 0.02 mm Hg/ml, p = 0.0001) and an increase in LA ejection fraction (27% +/- 7% to 38% +/- 8%, p < 0.005). There was a significant curvilinear relation between LA ejection fraction and LV stiffness (r = 0.63, p < 0.01). The mitral A velocity correlated positively with LA ejection fraction (r = 0.77, p < 0.0001) and inversely with LV stiffness (r = -0.52, p < 0.01). The reversible LA dysfunction suggests that the initial LA dysfunction is due to LA afterload mismatch rather than intrinsic LA disease, which also contributes to the augmentation of the mitral A velocity after heart failure treatment.

Prostaglandin E2 predominantly induces production of hepatocyte growth factor/scatter factor in human dental pulp in acute inflammation.

Hepatocyte growth factor (HGF), which is also known as the scatter factor, is a broad-spectrum and multifunctional cytokine, mediates epithelial-mesenchyme interaction, and is shown to be involved in the development and regeneration of various tissues, including tooth. Here, we report that HGF was present in adult human dental pulps, and its levels increased during acute inflammation of the tissue. Levels of HGF mRNA in dental pulps also increased with inflammation, as determined by reverse-transcription/polymerase chain-reaction. The production of HGF in fibroblasts from dental pulps in culture was dose-dependently stimulated by inflammatory cytokines such as interleukin (IL)-1alpha and tumor necrosis factor (TNF)-alpha, and by prostaglandin (PG) E2, as determined by an enzyme-linked immunosorbent assay. We also showed that indomethacin did not affect the increase in HGF production by the cells with IL-1alpha, TNF-alpha, and PGE2. The levels of HGF mRNA in the cells were simultaneously increased by these stimulants, as determined by Northern blotting. Since the production of PGs is known to increase at the beginning of inflammation, PGE2 may be involved in the regeneration of dental pulps by the induction of HGF expression after inflammation.

A theoretical method for distinguishing between soluble and membrane proteins.

A method for distinguishing between membrane and soluble proteins in an amino acid sequence was developed, using only two parameters associated with the hydrophobicity: the average hydrophobicity and the power spectral density of period longer than 30 residues. The power spectral density was calculated by a maximum entropy method of Fourier transformation. Membrane proteins could be distinguished from soluble proteins with a distinction rate as high as 97%. This fact strongly suggests that the morphology of proteins, i.e., membrane or soluble forms, is determined thermodynamically through the hydrophobicity of polypeptides.