In Japan,Camellia japonica and Camellia rusticana are naturally distributed.Despite differences in their habitats and morphologies,they have been classified by various researchers as either varieties,subspecies,or spe...In Japan,Camellia japonica and Camellia rusticana are naturally distributed.Despite differences in their habitats and morphologies,they have been classified by various researchers as either varieties,subspecies,or species.The taxonomic position of C.japonica and C.rusticana remain unclear because morphological comparisons have been restricted to limited areas and quantitative data are scarce.C.rusticana grows in snowy places,unlike C.japonica.While C.japonica displays ornithophily,C.rusticana displays entomophily.Both species have adapted to different growing environments and pollinators,which have altered the morphology of flowers and leaves.We therefore quantitatively estimated the differentiation between these two taxa by comparing the morphologies of leaf hypodermis,flower form,petal color,and filament color in twenty populations.Our findings allowed us to differentiate these two species by the presence or absence of a leaf hypodermis.We also discovered an intermediate type of leaf hypodermis,which might also be caused by hybridization.Principal component analysis(PCA)indicated that the flower morphologies between these species were significantly different.The petal and filament colors were also significantly different.Our quantitative analysis suggests that speciation caused by differences in both pollinators and environment is one of the factors involved in this group.These findings in C.japonica and C.rusticana help to explain speciation processes for other species as well.展开更多
The number of diabetic patients has recently been increasing all over the world together with lifestyle changes including sedentary life and high-calorie diet intake, and as a result the increase in these suffering fr...The number of diabetic patients has recently been increasing all over the world together with lifestyle changes including sedentary life and high-calorie diet intake, and as a result the increase in these suffering from diabetes mellitus has become a global issue. Diabetic animal models play a key role in bettering our understanding of the pathophysiology of diabetes and in developing new therapies for the disease. Diabetes is classified into two types, type 1 and type 2, and type 2 diabetes is chiefly caused by a depletion of insulin secretion in the pancreas and insulin resistance in peripheral tissues. The Goto-Kakizaki (GK) rat and the Spontaneously Diabetic Torii (SDT) rat are genetic non-obese type 2 diabetic models, and the both rats are considered to be suitable models for investigating the etiology of the depletion of insulin secretion and impaired glucose tolerance. In this review, we overviewed the outline of pathophysiological features in GK rats and SDT rats, including biological parameters and pharmacological responses.展开更多
基金This work was supported by Sado City Grant for Scientific Research on Biodiversity and Tadami-machi(2014e2016)was supported in part by the JSPS KAKENHI(Grant Number JP15K07473).
文摘In Japan,Camellia japonica and Camellia rusticana are naturally distributed.Despite differences in their habitats and morphologies,they have been classified by various researchers as either varieties,subspecies,or species.The taxonomic position of C.japonica and C.rusticana remain unclear because morphological comparisons have been restricted to limited areas and quantitative data are scarce.C.rusticana grows in snowy places,unlike C.japonica.While C.japonica displays ornithophily,C.rusticana displays entomophily.Both species have adapted to different growing environments and pollinators,which have altered the morphology of flowers and leaves.We therefore quantitatively estimated the differentiation between these two taxa by comparing the morphologies of leaf hypodermis,flower form,petal color,and filament color in twenty populations.Our findings allowed us to differentiate these two species by the presence or absence of a leaf hypodermis.We also discovered an intermediate type of leaf hypodermis,which might also be caused by hybridization.Principal component analysis(PCA)indicated that the flower morphologies between these species were significantly different.The petal and filament colors were also significantly different.Our quantitative analysis suggests that speciation caused by differences in both pollinators and environment is one of the factors involved in this group.These findings in C.japonica and C.rusticana help to explain speciation processes for other species as well.
文摘The number of diabetic patients has recently been increasing all over the world together with lifestyle changes including sedentary life and high-calorie diet intake, and as a result the increase in these suffering from diabetes mellitus has become a global issue. Diabetic animal models play a key role in bettering our understanding of the pathophysiology of diabetes and in developing new therapies for the disease. Diabetes is classified into two types, type 1 and type 2, and type 2 diabetes is chiefly caused by a depletion of insulin secretion in the pancreas and insulin resistance in peripheral tissues. The Goto-Kakizaki (GK) rat and the Spontaneously Diabetic Torii (SDT) rat are genetic non-obese type 2 diabetic models, and the both rats are considered to be suitable models for investigating the etiology of the depletion of insulin secretion and impaired glucose tolerance. In this review, we overviewed the outline of pathophysiological features in GK rats and SDT rats, including biological parameters and pharmacological responses.
