Effects of low-intensity, elastic band resistance exercise combined with blood flow restriction on muscle activation.

We examined the effects of blood flow-restricted, low-intensity resistance exercise (termed kaatsu) using an elastic band for resistance on muscle activation. Nine men performed triceps extension and biceps flexion exercises (four sets respectively) using an elastic band for resistance with blood flow restriction (BFR) or CON (unrestricted blood flow). During a BFR session, subjects wore pressure cuffs inflated to 170-260 mmHg on the proximal region of both arms. Surface electromyography (EMG) was recorded from the triceps brachii and biceps brachii muscles, and mean integrated EMG (iEMG) was analyzed. Blood lactate concentration was obtained before (Pre) and immediately after two exercises (Post). During triceps extension and biceps flexion exercises, muscle activation increased progressively (P < 0.05) under BFR (46% and 69%, respectively) but not under CON (12% and 23%, respectively). Blood lactate concentration at Post was higher (P < 0.05) under BFR than under CON (3.6 and 2.1 mmol/L, respectively). Blood lactate concentration at Post was significantly correlated with increased iEMG in both triceps extension (r = 0.65, P < 0.01) and biceps flexion exercises (r = 0.52, P < 0.05). We conclude that kaatsu training using elastic bands for resistance enhances muscle activation and may be an effective method to promote muscle hypertrophy in older adults or patients with a low level of activity.

Muscle size and arterial stiffness after blood flow-restricted low-intensity resistance training in older adults.

Previous studies have shown that blood flow-restricted low-intensity resistance training (BFR-RT) causes muscle hypertrophy while maintaining arterial function in young adults. We examined the effects of BFR-RT on muscle size and arterial stiffness in older adults. Healthy subjects (ages 61-84 years) were divided into BFR-RT (n = 9) or non-training control (CON; n = 10) groups. The BFR-RT group performed 20% and 30%, respectively, of one-repetition maximal (1-RM) knee extension and leg press exercises, 2 days/wk for 12 weeks. The BFR-RT group wore elastic cuffs (120-270 mmHg) on both legs during training. Magnetic resonance imaging-measured muscle cross-sectional area (CSA), 1-RM strength, chair stand (CS) test, and cardio-ankle vascular index testing (CAVI), an index of arterial stiffness, were measured before and 3-5 days after the final training session. Muscle CSA of the quadriceps (8.0%), adductors (6.5%), and gluteus maximus (4.4%), leg extension and leg press 1-RM strength (26.1% and 33.4%), and CS performance (18.3%) improved (P < 0.05) in the BFR-RT group, but not in the CON group. In CAVI testing, there were no changes in both two groups. In conclusion, BFR-RT improves muscle CSA as well as maximal muscle strength, but does not negatively affect arterial stiffness or humeral coagulation factors in older adults.

Magnetically Advected Winds.

Observations of X-ray absorption lines in magnetically driven disc winds around black hole binaries and active galactic nuclei yield a universal radial density profile ρ ∝ r - 1.2 in the wind. This is in disagreement with the standard Blandford & Payne profile ρ BP ∝ r - 1.5 expected when the magnetic field is neither advected nor diffusing through the accretion disc. In order to account for this discrepancy, we establish a new paradigm for magnetically driven astrophysical winds according to which the large scale ordered magnetic field that threads the disc is continuously generated by the Cosmic Battery around the inner edge of the disc and continuously diffuses outward. We obtain self-similar solutions of such magnetically advected winds (MAW) and discuss their observational ramifications.

Temporal and spatial expressions of transforming growth factor-betas and their receptors in epiphyseal growth plate.

The activities of TGF-beta and its receptors in enchondral ossification have not yet been fully elucidated. The temporal and spatial expressions of TGF-beta and its receptors were examined immunohistochemically in epiphyseal growth plate of rats, in order to clarify the roles of TGF-beta and receptors in cartilage cells during enchondral ossification. TGF-beta1 and TGF-beta3 were expressed from 6 to 24 weeks in resting, proliferating, and maturing zone. TGF-beta2 was expressed at 6 week, but decreased during growth. The expression of TGF-betas in hypertrophic chondrocytes was weak. TbetaR-I was co-expressed with the ligand in resting, proliferating, and maturing zone throughout the development. The expressions of TbetaR-II was recognized at 6 weeks but decreased after that. This study suggests that TGF-betas play a major role in modulating endochondral ossification during growth in epiphyseal growth plate.

Effects of benzoic acid and its analogues on insulin and glucagon secretion in sheep.

The effects of benzoic acid and its analogues on insulin and glucagon secretion were investigated in conscious sheep. Intravenous injections of benzoic acid increased plasma insulin and glucagon concentrations in a dose-dependent manner between 39-1250 mumol/kg, with ED50s for increasing both hormones of about 625 mumol/kg. Various derivatives of benzoic acid (625 mumol/kg) were administered and structure-activity relationships were examined. A single carboxylic group was essential for stimulating insulin and glucagon secretion, since both hormone responses were abolished with compounds in which the carboxylic group was replaced by sulfonic or phosphoric groups, or in which another carboxylic element was introduced (phthalic acids). Most of the compounds which introduced other elements (amino and hydroxy groups, and halogens) onto the benzene ring had an altered stimulating activity. Thus the pancreatic endocrine system can recognize the chemical structure of benzoic acid and its derivatives in detail and induce insulin and glucagon secretion in sheep.

Unpredictable deprivation of water increases the probability of torpor in the Syrian hamster.

The effect of unpredictable water deprivation on hibernation was investigated in the Syrian hamster under natural photoperiod and temperature. Based on our previous findings, we hypothesized that 1) deprivation of water caused testicular regression, 2) the magnitude of regression depended on unpredictability of water deprivation, 3) unpredictable deprivation of water on 50% of the days of the experimental period causes more testicular regression for animals than regular deprivation every other day, even if the total lengths were the same for the two treatments, and thus, 4) unpredictable deprivation of water induces hibernation more readily than regular deprivation or no deprivation. The results showed that the animals with the random and unpredictable deprivation a) started hibernation earlier, b) had a higher chance of being in torpor at the end of hibernation season, c) spent more time in torpor during hibernation than those animals which were deprived of water on a regular basis or the control, non-deprived animals. These findings supported our working hypothesis.

Immunolocalization of transforming growth factor-beta s and type I and type II receptors in rat articular cartilage.

The activities of TGF-beta s and their receptors (T beta R) in the articular cartilage have not been fully elucidated as yet. Temporal and spatial expression of TGF-beta s and their receptors were examined immunohistochemically in the articular cartilage of growing rats to clarify their role in chondrogenesis. TGF-beta 1, -beta 2 and -beta 3 were strongly expressed from 6 to 50 weeks in the superficial, transitional, and least mature zones. The expression of TGF-beta s in hypertrophic chondrocyte was weak except TGF-beta 1. T beta R-I and T beta R-II were co-expressed with the ligand in the superficial, transitional, and least mature zones throughout the growth phase. This study revealed that TGF-beta s in the articular cartilage plays a major role in the modulation of endochondral ossification ensuring the growth and maintenance of the chondrocyte lineage in articular cartilage.

Blood flow rate in normal and tumor-bearing rats in conscious state, under urethane anesthesia, and during systemic hypothermia.

The blood flow rates of 14 tissues in the body were determined by microsphere method using normal and tumor-bearing rats kept conscious or under urethane anesthesia. The effects on the blood flow rate in the tissues were assessed for multimodal therapy, systemic hypothermia for ischemic brain injury, and local hyperthermia and angiotensin II-induced hypertensive chemotherapy for cancer. Urethane anesthesia showed no effect on cardiac output, while there was a tendency of decrease of blood flow rate and % of cardiac output in each tissue other than muscle tissue, in which they increased as a counterbalance, in normal and tumor-bearing rats. Systemic hypothermia gave results similar to those of urethane anesthesia in normal rats, but for tumor-bearing rats, it decreased cardiac output, and consequently the blood flow rate in most tissues. Brain blood flow rate was about half of that in the conscious rats. Local hyperthermia also decreased the cardiac output and blood flow rate in each tissue, including the tumor tissue. Angiotensin II-induced hypertension showed no effect on cardiac output, had various effects on blood flow rate in each tissue, and led to no increase in the tumor blood flow rate. Simulations based on the physiological pharmacokinetic modeling suggested that intramuscular injection of a lung-specific derivative of ceftazidime would provide the ideal biodistribution to ensure its optimal therapeutic efficacy during systemic hypothermia. This methodology, namely the pharmacokinetic simulation based on the physiological values of the body, will provide a useful piece of information on drug delivery systems under various conditions.

Analysis program based on finite element method, MULTI(FEM), for evaluation of dose-dependent local disposition of drug in liver.

A curve-fitting program based on the Finite Element Method, MULTI(FEM), was developed to model nonlinear local disposition of a drug in the liver under non-steady-state conditions. The program was written in FORTRAN on an IBM-compatible personal computer. The validity of MULTI(FEM) was confirmed by analyzing the outflow kinetics of oxacillin (a model drug) following a pulse input to isolated, perfused rat livers, according to both linear and nonlinear dispersion models. Four dose levels (300, 1000, 3000, and 5000 microg) of oxacillin were administered to observe the dose-dependency in the hepatic local disposition. First, the individual outflow time-profiles at the same dose were averaged, and the average time-profile was analyzed by MULTI(FEM) based on linear dispersion models to yield a single curve fit. The fitted parameters at each dose level were compared with parameters estimated using MULTI(FILT), a program based on fast inverse Laplace transform, to analyze linear pharmacokinetics. The estimated parameters by MULTI(FEM) were in good agreement with those by MULTI(FILT). The apparent elimination rate constant (ke) decreased with an increase in dose, whereas other parameters showed no discernible dependency on an increase of dose. Second, the average outflow time-profiles at the four dose levels were simultaneously analyzed by MULTI(FEM) based on dispersion models featuring Michaelis-Menten elimination. The outflow time-profiles of oxacillin were well approximated by a two-compartment dispersion model with central Michaelis-Menten elimination. The maximum elimination rate constant (Vmax) and the Michaelis constant (Km) were estimated to be 1520 microg/mL/min and 41.3 microg/mL, respectively. Thus, the capability of MULTI(FEM) was demonstrated in evaluating capacity-limited local disposition in the liver.

The effect of adaptive iterative dose reduction on image quality in 320-detector row CT coronary angiography.

OBJECTIVE: To evaluate the effect of adaptive iterative dose reduction (AIDR) on image noise and image quality as compared with standard filtered back projection (FBP) in 320-detector row CT coronary angiography (CTCA). METHODS: 50 patients (14 females, mean age 68 ± 9 years) who underwent CTCA (100 kV or 120 kV, 400-580 mA) within a single heartbeat were enrolled. Studies were reconstructed with FBP and subsequently AIDR. Image noise, vessel contrast and contrast-to-noise ratio (CNR) in the coronary arteries were evaluated. Overall image quality for coronary arteries was assessed using a five-point scale (1, non-diagnostic; 5, excellent). RESULTS: All the examinations were performed in a single heartbeat. Image noise in the aorta was significantly lower in data sets reconstructed with AIDR than in those reconstructed with FBP (21.4 ± 3.1 HU vs 36.9 ± 4.5 HU; p<0.001). No significant differences were observed between FBP and AIDR for the mean vessel contrast (HU) in the proximal coronary arteries. Consequently, CNRs in the proximal coronary arteries were higher in the AIDR group than in the FBP group (p<0.001). The mean image quality score was improved by AIDR (3.75 ± 0.38 vs 4.24 ± 0.38; p<0.001). CONCLUSION: The use of AIDR reduces image noise and improves image quality in 320-detector row CTCA.

Reaction characteristics of an immobilized yeast producing ethanol.

The reaction behavior of Saccharomyces formaosensis imobilized by polyacrylamide gel is presented. Two types of the immobilized yeast are studied, i. e. the immobilized resting yeast and the immobilized growing yeast. For both of the yeast, reaction retes are expressed by the Michaelis-Menten type equation with a linear ethanol inhibition factor. The Michaelis constants aere close each other, but considerably larger that of native S. cerevisiae. Distribution of the growing yeast cell inside the carrier gel is presented. It is found that the cell density is somewhat higher near the surface of the carrier.

Distribution of leptospirosis among stray dogs in the Okinawa Islands, Japan: comparison of the microcapsule and microscopic agglutination tests.

Three hundred and thirty-eight sera collected from stray dogs in the Okinawa islands were examined for antibodies against Leptospira interrogans using the microscopic agglutination test (MAT) and the one-point microcapsule agglutination test (MCAT). Seventy-eight sera (23%) showed a positive reaction to at least one of the six serovar antigens, and 69 of these reacted with serovar canicola by microcapsule agglutination test. The mixed microcapsule agglutination test detected 68 of the microscopic agglutination test-positive sera, and the 10 remaining were negative by microcapsule agglutination test. On the other hand, a single microcapsule agglutination test which was sensitized with serovar canicola detected 77 of the microscopic agglutination test-positive sera and the remaining one was microcapsule agglutination test-negative.

Pharmacokinetic analysis program based on tank-in-series model, MULTI(TIS), for evaluation of capacity-limited local disposition.

A pharmacokinetic analysis program based on a tank-in-series model, MULTI(TIS), was developed for the evaluation of dose-dependency in the local disposition of a drug. The program written in FORTRAN was constructed by expanding MULTI(RUNGE). The reliability of MULTI(TIS) was verified by analyzing the experimental data based on linear and nonlinear tank-in-series models. Linear one- and two-compartment tank-in-series models were adopted to analyze outflow time profiles in single-pass hepatic perfusion following a pulse input of 5'-deoxy-5-fluorouridine (DFUR). The estimated parameters agreed well with those by MULTI(FILT) which is widely used for linear kinetic analysis. The nonlinear models adopted were one-compartment model with Michaelis-Menten elimination and two-compartment models with Michaelis-Menten elimination from central and peripheral compartments. Oxacillin was used as a model drug, because time courses of oxacillin show a capacity-limited hepatic disposition following a pulse input in high doses to the liver (300, 1000, 3000 and 5000 microg). The hepatic recovery ratio (F(H)) of oxacillin increased with dose, whereas the mean transit time (tH) was almost constant. The maximum elimination rate constant (Vmax) and Michaelis constant (Km) of oxacillin were estimated to be 1980 microg/ml/min and 54.1 microg/ml, respectively. Thus, the reliability of MULTI(TIS) was demonstrated for the analysis of nonlinear local disposition, especially, capacity-limited elimination in the liver.

The first epidemic of acute hemorrhagic conjunctivitis due to a coxsackievirus A24 variant in Okinawa, Japan, in 1985-1986.

Epidemics of acute hemorrhagic conjunctivitis due to a coxsackievirus A24 variant occurred in July-November, 1985 and August-October, 1986 in Okinawa Prefecture, Japan. This is the first report of an acute hemorrhagic conjunctivitis epidemic due to a coxsackievirus A24 variant in Japan The epidemic involved most islands of the prefecture. The prefectural surveillance center was notified of 9,952 cases in 1985 and 6,096 cases in 1986 from three sentinel eye clinics. The neutralizing antibody-positive rate against the coxsackievirus A24 variant of the serum samples collected before and immediately after the 1985 epidemic rose from 1.0% to 8.5%. The coxsackievirus A24 variant was isolated from 48 out of 68 conjunctival swabs collected during the epidemics. The isolates were indistinguishable antigenically in the plaque reduction test from the prototype strain, EH24/70, but had a markedly distinct oligonucleotide pattern.