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91.
92.
Facilitation and sand burial affect plant survival during restoration of a tropical coastal sand dune degraded by tourist cars
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Coastal sand dunes support various ecosystem services, including storm protection and tourism. Restoration programs are often critical to preserve this ecosystem due to its fragility and high degree of degradation. Dune restoration still suffers from a general lack of knowledge of the ecological processes controlling tropical dune communities. We investigated if facilitation can increase restoration success by assisting plant survival in a Brazilian coastal dune degraded by buggies at the Environmental Protection Area of Jenipabu, RN, Brazil. We performed two field experiments on dune crest sites degraded by buggies. The first experiment tested how the presence of established vegetation and coconut mesh, mimicking soil‐stabilizing effect of vegetation, facilitates seedling survival and establishment of the early successional dominant dune plant Canavalia maritima (Fabaceae). The second experiment tested if coconut mesh and initial irrigation would allow the establishment of C. maritima outside the vegetation, using both seeds and transplants. We found that the presence of established vegetation positively affected seedling survival. Application of mesh positively affected microclimatic conditions and slightly increased survival, but only for seeds. Initial irrigation only had a small effect on transplanted seedlings survival. Nevertheless, there was extreme seedling mortality in the experiment in particular from sand burial. We conclude that restoration of these dune crests is very difficult. Facilitation by vegetation can reduce plant mortality by sand burial and desiccation, but successful restoration is likely to require a major effort involving a very high number of seedlings or seeds. 相似文献
93.
Kazutoshi Fujibayashi Toshiaki Gunji Hirohide Yokokawa Toshio Naito Noriko Sasabe Mitsue Okumura Kimiko Iijima Katsuhiko Shibuya Teruhiko Hisaoka Hiroshi Fukuda 《PloS one》2016,11(3)
Background
Most studies on the relationships between metabolic disorders (hypertension, dyslipidemia, and impaired glucose tolerance) and hepatic steatosis (HS) or visceral fat accumulation (VFA) have been cross-sectional, and thus, these relationships remain unclear. We conducted a retrospective cohort study to clarify the relationships between components of metabolic disorders and HS/VFA.Methods
The participants were 615 middle-aged men who were free from serious liver disorders, diabetes, and HS/VFA and underwent multiple general health check-ups at our institution between 2009 and 2013. The data from the initial and final check-ups were used. HS and VFA were assessed by computed tomography. HS was defined as a liver to spleen attenuation ratio of ≤1.0. VFA was defined as a visceral fat cross-sectional area of ≥100 cm2 at the level of the navel. Metabolic disorders were defined using Japan’s metabolic syndrome diagnostic criteria. The participants were divided into four groups based on the presence (+) or absence (-) of HS/VFA. The onset rates of each metabolic disorder were compared among the four groups.Results
Among the participants, 521, 55, 24, and 15 were classified as HS(-)/VFA(-), HS(-)/VFA(+), HS(+)/VFA(-), and HS(+)/VFA(+), respectively, at the end of the study. Impaired glucose tolerance was more common among the participants that exhibited HS or VFA (p = 0.05). On the other hand, dyslipidemia was more common among the participants that displayed VFA (p = 0.01).Conclusions
It is likely that VFA is associated with impaired glucose tolerance and dyslipidemia, while HS might be associated with impaired glucose tolerance. Unfortunately, our study failed to detect associations between HS/VFA and metabolic disorders due to the low number of subjects that exhibited fat accumulation. Although our observational study had major limitations, we consider that it obtained some interesting results. HS and VFA might affect different metabolic disorders. Further large-scale longitudinal studies are needed to reveal the relationships between the components of metabolic disorders and HS/VFA. 相似文献94.
Gerhard E. Overbeck Eduardo Vlez‐Martin Fabio R. Scarano Thomas M. Lewinsohn Carlos R. Fonseca Sebastian T. Meyer Sandra C. Müller Paula Ceotto Letícia Dadalt Giselda Durigan Gislene Ganade Martin M. Gossner Demetrio L. Guadagnin Katrin Lorenzen Claudia M. Jacobi Wolfgang W. Weisser Valrio D. Pillar 《Diversity & distributions》2015,21(12):1455-1460
95.
Maki Konno-Shimizu Nobutake Yamamichi Ken-ichi Inada Natsuko Kageyama-Yahara Kazuya Shiogama Yu Takahashi Itsuko Asada-Hirayama Mitsue Yamamichi-Nishina Chiemi Nakayama Satoshi Ono Shinya Kodashima Mitsuhiro Fujishiro Yutaka Tsutsumi Masao Ichinose Kazuhiko Koike 《PloS one》2013,8(2)
Gastric cancer (GC) presents various histological features, though the mechanism underlying its diversity is seldom elucidated. It is mainly classified into well differentiated tubular adenocarcinoma (tub1), moderately differentiated tubular adenocarcinoma (tub2), poorly differentiated adenocarcinoma (por), signet-ring cell carcinoma (sig), mucinous adenocarcinoma (muc), and papillary adenocarcinoma (pap). By screening, we found cathepsin E (CTSE) expresses universally in sig-type, occasionally in por-type, and rarely in tub1/tub2-type GC cell lines. In surgically-resected specimens, CTSE was immunostained in 50/51 sig-type (98.0%), 3/10 tub1-type (30.0%), 7/18 tub2-type (38.9%), 15/26 por-type (57.7%), 4/10 pap-type (40.0%), and 0/3 muc-type (0.0%) GC. In endoscopically-resected specimens, 6/7 sig-type (85.7%), 7/52 tub1-type (13.7%), 5/12 tub2-type (41.7%), 2/7 pap-type (28.6%) GC and 0/6 adenoma (0.0%) expressed CTSE. For non-malignant tissues, CTSE is universally expressed in normal fundic, pyloric, and cardiac glands of stomach, but hardly in other digestive organs. In the precancerous intestinal metaplasia of stomach, CTSE is mostly observed in mixed gastric-and-intestinal type and deficient in solely-intestinal type. CTSE expression is positively correlated with gastric marker MUC5AC (p<0.0001) and negatively correlated with intestinal marker MUC2 (p = 0.0019). For sig-type GC, in both tumors and background mucosa, expression of MUC5AC and CTSE is high whereas that of MUC2 is low, indicating that sig-type GC reflects the features of background mucosa. For gastric adenoma and tub1/tub2-type GC, more undifferentiated tumors tend to show higher expression of CTSE with MUC5AC and lower expression of MUC2 in tumors, but they tend to present lower expression of CTSE, MUC5AC and MUC2 in background mucosa. These suggest that more malignant gastric adenocarcinoma with stronger gastric and weaker intestinal properties tend to arise from background mucosa with decreased both gastric and intestinal features. In conclusion, CTSE is a marker of both gastric differentiation and signet-ring cell carcinoma, which should shed light on the mechanism of gastric tumorigenesis. 相似文献
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97.
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99.
Hong J Yokomakura A Nakano Y Ishihara K Kaneda M Onodera M Nakahama K Morita I Niikura K Ahn JW Zee O Ohuchi K 《FEBS letters》2006,580(11):2723-2730
Apicularen A and the known vacuolar-type (H(+))-ATPase (V-ATPase) inhibitor bafilomycin A(1) induced apoptosis of RAW 264.7 cells, while apicularen B, an N-acetyl-glucosamine glycoside of apicularen A, was far less effective. Apicularen A inhibited vital staining with acridine orange of the intracellular organelles of RAW 264.7 cells, inhibited the ATP-dependent proton transport into inside-out microsome vesicles, and inhibited the bafilomycin A(1)-sensitive ATP hydrolysis. The IC(50) values of the proton transport were 0.58 nM for apicularen A, 13 nM for apicularen B, and 0.95 nM for bafilomycin A(1). Furthermore, apicularen A inhibited the bafilomycin A(1)-sensitive ATP hydrolysis more potently than apicularen B. F-ATPase and P-ATPase were not inhibited by apicularen A. We concluded that apicularen A inhibits V-ATPase, and thus induces apoptosis in RAW 264.7 cells. 相似文献
100.
Fabiano A. Fernandes Gislene L. Gonçalves Simone S. F. Ximenes Thales R. O. de Freitas 《Genetica》2009,136(3):449-459
The rodent genus Ctenomys (tuco-tucos) comprises more than 60 described species, and shows extraordinary inter- and intraspecific karyotypic variation.
The most widely distributed species of Ctenomys in Brazil is C. torquatus. Although several cytogenetic studies have been done, the karyotypic variability of this species is still poorly known. In
this paper we report two new diploid numbers for C. torquatus: 2n = 40 and 2n = 42, both showing AN = 72. The new distribution limits of C. torquatus here reported include localities in the southern, central and western parts of Rio Grande do Sul (RS) State in southern Brazil.
The phylogenetic relationship between C. torquatus from Alegrete, RS, and Ctenomys sp. from Corrientes, Argentina, is described by means of mtDNA cytochrome b analysis. Although both entities share similar karyotypes and sperm morphology, these two species are not phylogenetically
close. 相似文献