Relationship between cerebral activity and movement frequency of maximal finger tapping

To examine the cerebral activity of the motor cortex during maximum movement, we measured regional cerebral blood flow (rCBF) in twelve normal volunteers, using near infrared spectroscopy (NIRS). Repetitive tapping of the right index finger was performed at 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, and 4.5 Hz, and during maximum effort (ME). The relative increase rate of rCBF during movement beginning with a resting condition was calculated for each movement condition. The left primary sensorimotor cortex showed significant activation during ME compared to the other frequencies. The rapid increase of rCBF was seen immediately after the initiation of finger tapping at all the tested frequencies but showed no increase following that. However, the rCBF during ME continued to increase until the end of the task.Change of the integrated electromyogram (iEMG) for the frequency and change of rCBF for the frequency at all the tested frequencies showed similar tendencies.     

Continuous production of oxytetracycline by immobilized growing Streptomyces rimosus cells

Summary Streptomyces rimosus cells were immobilized with urethane prepolymers and used in the production of oxytetracycline. Based on the criteria for oxytetracycline productivity, cell growth in gels, cell leakage from gels and mechanical strength of gel, a hydrophilic prepolymer, PU-1, the main chain of which was polyethylene glycol (molecular weight, approximately 1500) was employed as gel material among 11 kinds of urethane prepolymers. Use of glucose-free medium for cultivation of PU-1-entrapped cells increased the production rate of oxytetracycline and minimized cell leakage from the gels. When the gel-entrapped cells lost activity, treatment of the cell-entrapping gels with saline or 70% ethanol resulted in recovery of the oxytetracycline productivity. Continuous oxytetracycline fermentation using PU-1-entrapped growing cells was successfully achieved in air-bubbled reactor for at least 35 days with reactivation of the cells.     

Alteration in molecular species of phosphatidylethanolamine between anesthetic resistant and sensitive strains of drosophila melanogaster

An analysis of lipid composition was carried out in resistant and sensitive strains of $\text{Drosophila}$$\text{melanogaster}$. Amount of total lipid and amount of phosphate of phospholipids were not different from each other in both strains. Phosphatidylethanolamine (PE) and phosphatidylcholine (PC) did not differ in amount between both strains. Determination of molecular species of PE using gas chromatography (GC) and GC-mass spectrometry showed that the resistant strain had increased 34:2 and decreased 36:2, 36:3 and 36:5 relative to the sensitive strain. The molecular species of PC did not differ between the two strains. Chromosomal analysis revealed that the alterations in 34:2 and 36:2 of PE were regulated by the X- and third chromosomes of the resistant strain. Therefore, the changes in PE may explain the mechanism of anesthetic resistance because genetic analyses indicate that these chromosomes have more influence on the anesthetic resistant traits of the resistant strain.     

Diversity of fungal DNA in lake sediments on Vega Island,north-east Antarctic Peninsula assessed using DNA metabarcoding

Extremophiles - We assessed the diversity of fungal DNA present in sediments of three lakes on Vega Island, north-east Antarctic Peninsula using metabarcoding through high-throughput sequencing...     

An expression profile analysis of ES cell-derived definitive endodermal cells and Pdx1-expressing cells

Background  

We developed an efficient in vitro method to differentiate mouse ES cells into the definitive endoderm (DE) and then Pdx1-expressing pancreatic lineages using mesodermal-derived supporting cells, M15. Using this method, resulting ES cell-derived DE and Pdx1-expressing cells were isolated by cell sorting, and their gene expression profiles were investigated with DNA microarray. Genes that were specifically expressed in DE and/or in Pdx1-expressing cells were extracted and their expression patterns in normal embryonic development were studied.     

A comparative study of % fat and living style on nepalese

Measurements of %Fat, nutrient intake and maximal aerobic power (MAP) were carried out on Nepalese to clarify the cause of obesity attended with modernization. One hundred thirty-two males (KV) who have a natural living style, 20-84 years of age, in rural district and 237 males who have a living style affected by the rapid urbanization, in surburban district were selected as subjects. The subjects of surburban district were divided into two groups. One of them included 147 farmers (BF) who engage in not mechanized farming, 20-73 years of age. Another group included 90 students and wage laborers (BNF) who go to and from Kathmandu (the capital of Nepal), 20-57 years of age. %Fat was estimated from skinfold thickness according to the method of Nagamine (1975). The survey for the nutrient intake was carried out by the 24-hour recall method to obtain the individual food consumption using the food models. Measurement of MAP was made indirectly by the modified of Margaria et al (1965). The main results are summarized as follows. 1) Mean %Fat and the appearance rates of obesity in each age group showed high values in following order: BNF greater than BF greater than KV. 2) Mean caloric intake in KV was higher than those in BF and in BNF an almost all age groups and no significant difference was found between BF and BNF in all age groups. 3) No significant differences in mean fat intake and in mean animal fat intake among all groups were found in almost all age groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Determination of the enzymatic activity of pectinases from different microorganisms

The decrease in viscosity is widely used to estimate the activity of pectinolytic enzymes. This method is shown to be influenced by the production strain and this prevents an accurate comparison between the activities of different microorganisms, especially under different conditions.A.E. Maiorano and Y. Ogaki are with the Divisão de Quimica, with the Agrupamento de Biotecnologia, Instituto de Pesquisas Tecnológicas do Estado de São Paulo S/A.-IPT, Cidade Universitária, Caixa Postal 7141, CEP 01064-970, São Paulo, SP, Brazil; W. Schmidell is with the Departamento de Engenharia Quimica, Escola Politécnia, Universidade de São Paulo, Caixa Postal 61548, CEP 05424-970, São Paulo, SP, Brazil.     

Cardiorespiratory response to low-intensity walking in water and on land in elderly women.

The purpose of the present study was to determine whether or not the exercise intensity of water-walking for elderly women could be accurately prescribed by heart rate data obtained during treadmill exercise on land. Six healthy female volunteers, with a mean age of 62.2 +/- 4.2 years, took part in this study. Walking on land was performed on a treadmill. Each subject completed three consecutive 4-minute walks at a progressively increasing velocity (40, 60 and 80 m.min-1), with a 1-minute rest after both the first and second walks. The room temperature and relative humidity were 24.5 +/- 0.2 degrees C and 54.8 +/- 4.0%, respectively. Walking in water was performed in a Flowmill, which is a treadmill positioned at the base of a water flume. Each subject completed three consecutive 4-minute walks at a progressively increasing belt and water-flow velocity (20, 30 and 40 m.min-1), with a 1-minute rest after both the first and second walks. The water depth was at the level of the xiphoid process of each subject. The water temperature was 30.7 +/- 0.1 degrees C. The exercise intensity at the highest workrate was equivalent to 44.2 +/- 10.3% of the heart rate reserve (HRR) during water-walking and 38.4 +/- 4.7% of the HRR during land-walking. There was a highly significant linear relationship between heart rate (HR) and oxygen uptake (VO2) during both water-walking and land-walking. The relationship between HR and VO2 in both exercise modes was similar. Thus, the relationship of HR to VO2 derived from a treadmill-graded walking test on land may be used to prescribe exercise intensity for water-walking in thermoneutral water.     

The effect of maximal finger tapping on cerebral activation

The purpose of the present study was to investigate the effect of the repetition rate of a simple movement on the magnitude of neuronal recruitment at maximal effort in humans. Nine right-handed healthy subjects [age: 27.4 +/- 4.8 yr, stature: 174.5 +/- 12.2 cm, body-weight 74.3 +/- 16.6 kg (Mean +/- SD)] participated in this study. We measured the regional cerebral hemodynamics using 24-channel near infrared spectroscopy (NIRS). An auditory-cued, repetitive flexion movement of the right index finger against a button was performed as the finger-tapping task at maximal effort (ME), at 25% of maximal effort (25% ME) and at 50% of maximal effort (50% ME). The increase of the left primary motor cortex hemodynamics during movement relative to the hemodynamics under the resting condition was calculated for each pair of movement conditions. The frequency of finger-tapping was 1.61 +/- 0.18 Hz (25% ME trial), 3.23 +/- 0.36 Hz (50% ME trial), and 6.46 +/- 0.72 Hz (ME trial). The left primary motor cortex showed significant activation under all conditions. The change in total hemoglobin ([tHb]) between the ME trial and the resting value (1.19 +/- 0.93 mmol.mm) was significantly higher than those between the resting value and the 25% ME trial (0.04 +/- 0.04 mmol.mm) or the 50% ME trial (0.08 +/- 0.11 mmol x mm) (p < 0.05). There was a 29.8-fold increase of the [tHb] value between the 50% ME trial and the ME trial, but only a 2-fold increase of the [tHb] value between the 25% ME trial and the 50% ME trial. These results demonstrated that the rate of change in regional cerebral hemoglobin at a maximal effort finger-tapping task was much higher than that at a low frequency finger-tapping task.     

Thermoregulatory responses to low-intensity prolonged swimming in water at various temperatures and treadmill walking on land

The purpose of the present study was to examine the effect of water temperature on the human body during low-intensity prolonged swimming. Six male college swimmers participated in this study. The experiments consisted of breast stroke swimming for 120 minutes in 23 degrees C, 28 degrees C and 33 degrees C water at a constant speed of 0.4 m.sec-1 in a swimming flume. The same subjects walked on a treadmill at a rate of approximately 50% of maximal oxygen uptake (VO2max) at the same relative intensity as the three swimming trials. Rectal temperature (Tre) in 33 degrees C water was unchanged during swimming for 120 minutes. Tre during treadmill walking increased significantly compared to the three different swimming trials. Tre, mean skin temperature (Tsk) and mean body temperature (Tb) in 23 degrees C and 28 degrees C water decreased significantly more than in both the 33 degrees C water and walking on land. VO2 during swimming in 23 degrees C water increased more than during swimming in the 28 degrees C and 33 degrees C trials; however, there were no significant differences in VO2 between the 23 degrees C swimming trial and treadmill walking. Heart rate (HR) during treadmill walking on land increased significantly compared with HR during the three swimming trials. Plasma adrenaline concentration at the end of the treadmill walking was higher than that at the end of each of the three swimming trials. Noradrenaline concentrations at the end of swimming in the 23 degrees C water and treadmill walking were higher than those during the other two swimming trials. Blood lactate concentration during swimming in 23 degrees C water was higher than that during the other two swimming trials and walking on land. These results suggest that the balance of heat loss and heat production is maintained in the warm water temperature. Therefore, a relatively warm water temperature may be desirable when prolonged swimming or other water exercise is performed at low intensity.