Curvature, length, and cross-sectional geometry of the femur and humerus in anthropoid primates

The aims of this study were to describe the curvature of anthropoid limb bones quantitatively, to determine how limb bone curvature scales with body mass, and to discuss how bone curvature influences static measures of bone strength. Femora and humeri in six anthropoid genera of Old World monkeys, New World monkeys, and gibbons were used. Bone length, curvature, and cross-sectional properties were incorporated into the analysis. These variables were obtained by a new method using three-dimensional morphological data reconstructed from consecutive CT images. This method revealed the patterns of curvature of anthropoid limb bones. Log-transformed scaling analyses of the characters revealed that bone length and especially bone curvature strongly reflected taxonomic/locomotor differences. As compared with Old World monkeys, New World monkeys and gibbons in particular have a proportionally long and less curved femur and humerus relative to body mass. It is also revealed that the section modulus relative to body mass varies less between taxonomic/locomotor groups in anthropoids. Calculation of theoretical bending strengths implied that Old World monkeys achieve near-constant bending strength in accordance with the tendency observed in general terrestrial mammals. Relatively shorter bone length and larger A-P curvature of Old World monkeys largely contribute to this uniformity. Bending strengths in New World monkeys and gibbons were, however, a little lower under lateral loading and extremely stronger and more variable under axial loading as compared with Old World monkeys, due to their relative elongated and weakly curved femora and humeri. These results suggest that arboreal locomotion, including quadrupedalism and suspension, requires functional demands quite dissimilar to those required in terrestrial quadrupedalism.     

L-Arabinose induces synthesis of secreted beta-galactosidase in the filamentous fungus penicillium canescens

The mechanism of induction of secreted beta-galactosidase was studied in the filamentous fungus Penicillium canescens. L-Arabinose and its metabolite L-arabitol induce the synthesis of the enzyme. Apart from beta-galactosidase, L-arabinose induces the synthesis of other extracellular carbohydrolases including alpha-L-arabinofuranosidase. Increasing L-arabinose concentration above 1 mM or addition of other carbon sources results in carbon catabolite repression of the synthesis of the secreted enzymes. The data suggest that arabinofuranosidase can regulate the synthesis of secreted enzymes in P. canescens, thus controlling the level of free L-arabinose.     

A method with three triangular flaps as a secondary operative procedure after reconstruction of the lower lip by Estlander's method.

We have devised a new method for secondary commissuroplasty after reconstruction of the lower lip using Estlander's method with both aesthetically and functionally satisfactory results. This method consists of forming two equilaterally triangular mucosal flaps on the vermilion and a small triangular skin flap in the new position of the commissure and transposing these three flaps to reconstruct the commissure. In the present paper, we reported the procedure and the results. This method produces extremely good results, obtaining favorable commissure form and reconstruction of the mucosa of both upper and lower lips without leaving an unnatural-looking color change in the mucosa or a step deformity in the vermilion. It can be expected that our method will improve the results of Estlander's operations after tumor resection in the lower lip.     

The effects of 20 days bed rest on serum lipids and lipoprotein concentrations in healthy young subjects

The effects of 20 days bed rest (BR) on serum lipids and lipoprotein concentrations were investigated in 23 healthy young subjects (13 males and 10 females, aged 19 to 25 yr.). After 20 days BR, VO2max was reduced in both genders, but body composition did not change. The ratio of glucose area to insulin area during an oral glucose tolerance test decreased gradually throughout BR, which suggested a decrease in insulin sensitivity. Estimated changes in plasma volume from the beginning of BR were largest at day 3 of BR (-9.1% in females and -3.4% in males) and seemed to return the initial level at the end of BR in both genders. The increase in serum triglycerides and the decrease in high density lipoprotein (HDL) cholesterol, and apolipoprotein AI were observed in both genders during BR. In a smaller study of 4 males and 5 females, 20 days BR was associated with a decrease in HDL, cholesterol, a decrease in apolipoprotein AI and apolipoprotein AII, decrease in a plasma postheparin lipoprotein lipase activity and an increase in very low density lipoprotein triglyceride. Overall, the data suggested that the decrease in lipoprotein lipase activity and insulin sensitivity may contribute to the impairment in HDL metabolism.     

Effects of the renin-angiotensin-aldosterone system on the cardiovascular system during 20-days bed rest

Long term change of renin-angiotensin-aldosterone system (RAAS) induced by bed rest and its effects on cardiovascular system are still controversial. The purpose of this study was to obtain a general conclusion on these questions by analyzing our two 20-days horizontal bed rest experiments in past two years with 18 subjects. Plasma renin activity and aldosterone were consistently increased during the bed rest, but angiotensin II was increased only during the early days. Decrease in urinary sodium excretion and increase in urinary potassium excretion were observed during day 3-8 and day 7-12, respectively. Mean arterial pressure increased during day 3-8. Pulse pressure was returned to pre-bed rest level by day 10 after an initial decrease. All these results indicated an activated RAAS and its active effects on cardiovascular and overall fluid regulating systems during our horizontal bed rest studies. Direct effect of change in gravitational force on renal pressure-sensitive cells or effects related to physical inactivity may explain our results.     

Short review of human prolonged horizontal bed rest studies in Japan

As many as 700,000-1,000,000 Japanese are spending a substantial part of their life in bed not being able to resume standing position due to disease and/or accident. Our objectives were urgently derived from that fact. The research project group at Faculty of Medicine, University of Tokyo, in Japan have studied effects of prolonged horizontal bed rest on humans since 1990. Financial supports from the Japanese Ministry of Education (Grant-in aide for scientific research), National Aero Space Development Agency of Japan and Japan Federation for Health Sciences have enabled us to perform five prolonged bed rest experiments for 5 years from 1990 to 1994. Many scientists in Europe, America and Russia have already made a heap of studies on this subject since the latter half of 1940s (eg. 39). However, our studies mainly focused upon the effects of inactivity on human health to determine how to bring a human from inactivity back to an unrestricted active life. This short review is going to summarize our results obtained from 1990 to 1993.     

Activated renin-angiotensin-aldosterone system and its effects on cardiovascular system during 20-days horizontal bed rest

Change in circulating blood volume by bed rest has been suggested to effect on many cardiovascular responses after bed rest including orthostatic intolerance and exercise performance. However, there is a lack of consensus on effect of renin-angiotensin-aldosterone system (RAAS) on baseline heart rate and blood pressure during bed rest, although RAAS is the most potent fluid regulating system. The purpose of this study was to clarify the effect of RAAS on changes in baseline cardiovascular system and urine excretion.     

Identification and cloning of an Erwinia carotovora subsp. carotovora bacteriocin regulator gene by insertional mutagenesis

Avirulent Erwinia carotovora subsp. carotovora CGE234-M403 produces two types of bacteriocin. For the purpose of cloning the bacteriocin genes of strain CGE234M403, a spontaneous rifampin-resistant mutant of this strain, M-rif-11-2, was isolated. By Tn5 insertional mutagenesis using M-rif-11-2, a mutant, TM01A01, which produces the high-molecular-weight bacteriocin but not the low-molecular-weight bacteriocin was obtained. By thermal asymmetric interlaced PCR, the DNA sequence from the Tn5 insertion site and the DNA sequence of a contiguous 1,280-bp region were determined. One complete open reading frame (ORF), designated ORF2, was identified within the sequenced fragment. The 3' end of another ORF, ORF1, was located upstream of ORF2. A noncoding region and a putative promoter were located between ORF1 and ORF2. Downstream from ORF2, the 5' end of another ORF (ORF3) was found. Deduction from the nucleotide sequence indicated that ORF2 encodes a protein of 99 amino acids, which showed high homology with Yersinia enterocolitica Yrp, a regulator of enterotoxin (Y-ST) production; Escherichia coli host factor 1, required for Qbeta-replicase; and Azorhizobium caulinodans NrfA, required for the expression of nifA. ORF2 was designated brg, bacteriocin regulator gene. A fragment containing ORF2 and its promoter was amplified and cloned into pBR322 and pHSG415r, and the recombinant plasmids, pBYL1 and pHYL1, were transferred into E. coli DH5. Plasmid pBYL1 was reisolated and transferred into the insertion mutant TM01A01. Transformants carrying the plasmid, which was reisolated and designated pBYL1, re-produced the low-molecular-weight bacteriocin.     

Learning process by goldfish and its use of a local site as a map

The issue we address is whether an animal knows or understands the significance of learning. We constructed an animal's own conceptualization via resolving a paradox underlying the process of learning. We found a kind of self-similar pattern in the behavior of goldfish resolving a paradoxical experimental problem. The pattern can be considered as a solution to the paradox in the experiment. An animal's own learning should be revised through solving paradoxes. The dualism of mechanistic thinking and vitalism can thus be avoided.     

Robot control with biological cells

At present there exists a large gap in size, performance, adaptability and robustness between natural and artificial information processors for performing coherent perception-action tasks under real-time constraints. Even the simplest organisms have an enviable capability of coping with an unknown dynamic environment. Robots, in contrast, are still clumsy if confronted with such complexity. This paper presents a bio-hybrid architecture developed for exploring an alternate approach to the control of autonomous robots. Circuits prepared from amoeboid plasmodia of the slime mold Physarum polycephalum are interfaced with an omnidirectional hexapod robot. Sensory signals from the macro-physical environment of the robot are transduced to cellular scale and processed using the unique micro-physical features of intracellular information processing. Conversely, the response form the cellular computation is amplified to yield a macroscopic output action in the environment mediated through the robot's actuators.