Kinematic and kinetic characteristics of stepping over a 10-cm-high obstacle in older adults

[Purpose] The purpose of this research was to clarify the common responses shared by a high-falldown-risk group of older adults and develop an exercise-learning program to prevent falls. [Subjects] Thirty-four subjects were chosen from those who use the daycare program of a nursing home at least once a week. [Methods] All subjects were categorized in longer or shorter-MSL groups. Ninety-second stepping from two force plates to a 10-cm-high box was executed under three conditions. The locus length of the COP,toe-obstacle distance,and step length were used as experimental data. [Results] The coefficient between the MSL and COP was from 0.69 to 0.73. The shorter-MSL group showed smaller COP movements in the A-P direction and a smaller toe-obstacle distance between the single stepping and stepping with the visual task and between the single stepping and stepping with the auditory task. No significant difference was noted in the step length between the two groups. [Conclusion] The shorter-MSL group was easily affected by the dual-task, suggesting that the shorter-MSL group has a high risk of falling when negotiating obstacles. Stepping exercise with the dual-task using the COP movements as a feedback index may be useful for older adults who have a smaller MSL

The assessments of body sway on the static standing using the center of pressure

The Center of Pressure (COP) has been used in evaluation of balance and motion analysis research. When it is measured with such a platform systems, the COP is defined as the center of the total number of active transducers for each data sample collected. Smaller magnitude of the COP movement on static standing reflects greater ability of postural control. On the contrary, bigger magnitude of the COP movement on static standing reflects poorer ability of postural control. Though this theory has been supported by some researches, there are some exceptions. To clarify the meaning of measuring the COP movements on static standing, we focused on some parameters concerning the COP, reliability and validity of the COP, the way to use, the COP movements of static standing with balance disabled people, the effect of aging on static balance, the relationship between gender and static balance, the effect of a low alcohol dose, and the balance of the day

Effects of isometric exercise on hypertension

Hypertension is a serious problem in modern society. Between the ages of 60 and 74, the prevalence of hypertension is almost double its age-adjusted prevalence among people under 60 years old. Physical activity and cardiorespiratory fitness are important influences on blood pressure. Most physical activity interventions have utilized aerobic exercise, but recent studies suggest that isometric exercise is safe and has favorable effects on physical fitness, hypertension, and the psychological status. Isometric exercise in hypertensive populations appears to maintain the reductions in blood pressure achieved by endurance training, and may even elicit further reductions in blood pressure. However, as I am indicating, resistance training is not the only recommended approach to lower blood pressure, but should play a prominent role in any program designed to do so

The association between the thrifty genotype and energy expenditure during aerobic exercise in healthy males and females

The number of patients with diabetes is notably increasing in Japan. The thrifty genotype characteristics provide an explanation for this very high prevalence of diabetes. Especially, the Trp64Arg polymorphism in the β3-adrenergic receptor (β3-AR) gene is relatively common in Japanese people. Aerobic exercise is one of the major strategies for prevention and treatment of type 2 diabetes. The present study investigated whether the Trp64Arg polymorphism in the β3-AR gene is associated with a reduction in energy expenditure in aerobic exercise. Eighty-six non-obese healthy young people were recruited. Energy expenditure was measured using indirect calorimetry. The subjects performed an aerobic exercise program at 60% of their maximal heart rate for 30 minutes. The level of fat oxidation during aerobic exercise by male subjects with the Trp/Arg of the β3-AR gene was significantly lower than that by those with the Trp/Trp genotype. There was no difference observed in female subjects. It was demonstrated that the Trp64Arg polymorphism in the β3-AR gene is associated with the reduction of fat oxidation during aerobic exercise in healthy young males

Diversity in common epithelial carcinoma, simplicity in sarcoma and leukemia

In some type of leukemia and sarcoma, cancer development mechanism is straightforward ; aberrant activation of single oncogene transforms cells. Such oncogenes are master genes which function upstream of transcriptional cascade. On the other hand, cancer genome analyses clearly show that that of common epithelial cancers such as lung adenocarcinoma is related to accumulations of mutations in "non-master" oncogenes, leading to heterogeneity in aggressiveness and clinical behavior among their patients. Common epithelial carcinomas do not arise from mutations in specific oncogenes but from accelerated growth rate as a result of summation of growth advantage of each driver mutations on a different composition of oncogenes. Because most of human cancers are of epithelial origin, this heterogeneity gives us a challenge both in understanding the molecular mechanism of carcinogenesis and in the treatment of carcinoma

Up-regulation of VE-cadherin expression by the LMO2 complex promotes vascular remodeling

LMO2 and its binding partner TAL1/SCL have essential roles in both hematopoiesis and angiogenesis. Indeed, LMO2 is highly expressed in endothelial cells and hematopoietic stem cells (HSCs) almost exclusively (with exceptions) throughout life. Recently, the first birthplace of HSCs has been identified as hemogenic endothelial cells in the dorsal aorta in mammals. Firstly, the LMO2 complex including TAL1, GATA1/2/3 (i.e., GATA1 or GATA2 or GATA3), and LDB1 play a key role in endothelial to hemogenic endothelial cell transition in the dorsal aorta in producing HSCs. Another role of the LMO2 complex is to remodel the existing vascular system in angiogenesis. In 2007 and 2012, progress was made in dissecting the mechanism of vascular remodeling regulated by the LMO2 complex. Two of the pivotal role players in vascular remodeling, VE-cadherin and angiopoitin-2, were identified to be among the direct targets of the LMO2 transcription factor complex. In this review, the detailed mechanism in vascular remodeling via the LMO2 complex is discussed

The origin of the first blood cell

In mouse development, the first blood cell activity appears in the yolk sac at E7.5(embryonic day 7.5). However,this blood cell activity (primitive hematopoiesis)is restricted to red blood cells (primitive erythrocytes). The pluripotent hematopoietic stem cells which are able to differentiate into all kinds of peripheral blood cell (including lymphocytes)are initially identified in the AGM (aorta-gonad -mesonephros)region at E10.5(definitive hematopoiesis).In vitro studies suggest the presence of hemangioblasts,which can differentiate into both blood and endothelial cells. However, until recently, direct evidence of the presence of these hemangioblasts in vivo was not available, and the precise mechanism of the differentiation of hematopoietic cells from hemangioblasts was totally unknown. Recent progress in this field of study indicates that the first hematopoietic stem cells are generated through the hemogenic endothelium stage and are anatomically derived from the hemogenic endothelium in the dorsal aorta floor of the AGM region

Molecular mechanism of angiogenesis

Angiogenesis is one of the chief events both in development and postnatal pathological conditions. Recent extensive studies revealed the key signaling and transcriptional regulators of sprouting angiogenesis. Sprouting angiogenesis is a multistep process composed of endothelial loosening, endothelial cell migration, stalk elongation, anastomosis, and stabilization. Although the initial process of sprouting is triggered by soluble proangiogenic factors such as VEGF and FGF, the rather complicated subsequent step recruits many signaling and adhesion molecules which are pivotal players in autonomous and conditional specification in development. There is a marked similarity at the molecular level between embryogenic and postnatal angiogenesis. By its physiological constraint, endothelium differentiation is closely linked with blood cell specification. Many transcription factors with a major role in hematopoietic stem cell generation are also involved in angiogenesis

The force used to pick up an object with one upper extremity after picking up a heavy object contralaterally -The influence of the force for the unilateral picking up of an object on the force used on the opposite side-

This research is a re-investigation of the "Generation of excess grip force after picking up a heavier object with the contralateral hand" which was conducted by Noda[1]. Noda[1] reported that information on the weight when picking up an object with the thumb and index finger influences information on the weight when picking up an object with the contralateral arm. The results we obtained in this study agreed with Noda\u27s study[1]. From our study,we confirmed that information on the weight of objects when picking up influenced information on the weight when picking up an object on the opposite side

Degenerative and of regenerative changes in the dorsal funiculus of the cryoinjured spinal cord of rats -electron microscopic study-

The morphological changes were examined in the dorsal funiculus after cryoinjury to the spinal cord at Th10 in the rat. Cryoinjury was performed by contacting a liquid nitrogen-frozen metal rod with the dorsal surface of the spinal cord. The frozen spinal cord was thawed spontaneously. This freeze-thawing treatment was repeated three times. The histological changes were examined by light and electron microscopy from 2 to 60 days after cryoinjury. The present study focused on the electron microscopic findings of the degenerative and regenerative changes of nerve fibers and glial cells following injury. In typical Waller degeneration, myelin sheaths of degenerated axons were separated from oligodendrocytes, and phagocytozed by macrophages. Within the lesion, while glial cells including oligodendrocytes were degraded, some axons were rescued from the damage, surviving as demyelinated axons after the degradation of associated oligodendrocytes. Such demyelinated axons were later remyelinated by oligodendrocytes or Schwann cells. This might be a major factor contributing to the locomotive recovery of the animal. Growth cones were formed even after a long period following cryoinjury at the proximal stump of the injured nerves. This suggests that nerve fibers have a strong ability to regenerate in the spinal cord dorsal funiculus. A cavity was usually formed in the epicenter to rostral part of the lesion. Cavity formation is a critical barrier to spinal cord regeneration. The main strategies for spinal cord regeneration might be to rescue and restore neural tissues from degeneration, and prevent cavity formation by providing a sufficient blood supply to ensure tissue survival and axonal outgrowth