doi:10.1111/j.1741‐2358.2009.00309.x Domestic use of a disclosing solution for denture hygiene: a randomised trial Objectives: The purpose of this study was to investigate the effect of the domestic use of a disclosing agent for denture hygiene. Materials and methods: Completely edentulous participants wearing maxillary dentures were randomly assigned to one of the three intervention groups: (1) Follow‐up only (control; n = 12); (2) Oral and denture hygiene instructions (n = 10); (3) Instructions associated with the home use of a disclosing agent (1% neutral red; n = 10). Biofilm coverage area (%) over internal and external surfaces of the maxillary denture was assessed at baseline and after 14 and 90 days. Data were evaluated by generalised estimating equations based on score tests (α = 0.05). Results: The participants presented low changes for areas of biofilm coverage (14 days (%): internal: GI = 1.4 ± 0.9; GII = 1.5 ± 1.3; GIII = ?0.4 ± 0.9; external: GI = 1.4 ± 1.5; GII = 1.5 ± 1.4; GIII = ?0.4 ± 0.9; 90 days (%): internal: GI = 2.0 ± 0.9; GII = 2.2 ± 1.4; GIII = 0.3 ± 1.0; external: GI = 2.1 ± 1.4; GII = 2.2 ± 1.5; GIII = 0.3 ± 0.9). Changes were similar for the three groups (p = 0.293) and were not influenced by the test time (p = 0.218). Conclusion: It can be concluded that the home use of a disclosing agent for denture hygiene does not improve the removal of the biofilm, particularly for patients with adequate oral hygiene habits. 相似文献
Summary— The replica staining label fracture technique was used to analyse the distribution of cruzipain and Ssp4 in Trypanosoma cruzi. Intense labeling for the two proteins was seen on the E fracture face of amastigote forms. Gold particles did not co-localize with the intramembranous particles. Labeling was abolished by previous treatment of the parasites with phospholipase C from Trypanosoma brucei, which removes glycosylphosphatidyl inositol (GPI) anchored proteins. These observations suggest that cruzipain and Ssp4 are attached to the parasite surface via a GPI anchor. 相似文献
Some reports have described the interference of Leishmania on sand flies physiology, and such behavior most likely evolved to favor the development and transmission of the parasite. Most of these studies showed that Leishmania could modulate the level of proteases in the midgut after an infective blood meal, and decreased proteolytic activity is indeed beneficial for the development of promastigotes in the gut of sand flies. In the present study, we performed a detailed investigation of the intestinal pH in Lutzomyia longipalpis females naturally infected with Leishmania infantum and investigated the production of trypsin by these insects using different approaches. Our results allowed us to propose a mechanism by which these parasites interfere with the physiology of L. longipalpis to decrease the production of proteolytic enzymes. According to our hypothesis L. infantum promastigotes indirectly interfere with the production of trypsin by modulating the mechanism that controls the intestinal pH via the action of a yet non-identified substance released by promastigote forms inside the midgut. This substance is not an acid, whose action would be restrict on to release H+ to the medium, but is a substance that is able to interfere with midgut physiology through a mechanism involving pH control. According to our hypothesis, as the pH decreases, the proteolytic enzymes efficiency is also reduced, leading to a decline in the supply of amino acids to the enterocytes: this decline reduces the stimulus for protease production because it is regulated by the supply of amino acids, thus leading to a delay in digestion. 相似文献
The Walker and Syers model predict that phosphorus (P) availability decreases with time leading to a final stage known as retrogression. We tested the validity of the Walker and Syers model in the Canary Islands, a soil chronosequence ranging from 300 years to 11 million years under recurrent episodes of atmospheric dust-containing P inputs. In particular, we compared our results with those from the volcanic soil chronosequences described in the Hawaii Islands and in Arizona, as they share key biological and/or geological characteristics. In three islands of the Canarian Archipelago, we selected 18 independent sites dominated by mature Pinus canariensis forests and grouped them into six age classes. For each site, soil samples were analyzed for known proxies of soil nitrogen (N), P and cations availability. We also analyzed the P. canariensis needles for N, P and cation contents. We found tendencies similar to those observed in other soil chronosequences: maximum N and P concentrations at intermediate ages and lower P concentrations in the older soils. The nutrient dynamics suggested that the older sites may indeed be approaching the retrogression stage but at lower rates than in other similar chronosequences. Differences from other chronosequences are likely due to the drier Canarian climate, the higher P deposition rates originating from the nearby Sahara Desert and the top soil horizon studied. Our results confirm the validity of the Walker and Syers model for the Canary Islands despite the influence that the high P deposition rates and the seasonally dry climate may have on soil development and P pools in P. canariensis ecosystems.
Aims: To find new antifungal agents among essential oils from Brazilian Croton species. Methods and Results: Plant leaves were steam distilled and the obtained essential oils were analyzed by gas chromatography/mass spectroscopy. The main constituents were estragole and anethole for Croton zehntneri, methyl-eugenol and bicyclogermacrene for Croton nepetaefolius and spathulenol and bicyclogermacrene for Croton argyrophylloides. The antifungal activity of essential oils was evaluated against Candida albicans, Candida tropicalis and Microsporum canis by the agar-well diffusion method and the minimum inhibitory concentration (MIC) by the broth microdilution method. Essential oils of Croton species demonstrated better activity against M. canis. Among the three plants C. argyrophylloides showed the best results, with MIC ranging from 9 to 19 μg ml−1. The acute administration of the essential oil up to 3 g kg−1 by the oral route to mice was devoid of overt toxicity. Conclusions: The studied essential oils are active in vitro against the dermatophyte M. canis and present relative lack of acute toxicity in vivo. Significance and Impact of the Study: Because of its antifungal activity and low toxicity, the essential oils of studied Croton species are promising sources for new phytotherapeutic agents to treat dermatophytosis. 相似文献
Indigenous forest reserves represent approximately one fifth of Brazilian Amazonia and pose enormous challenges for sustainable
natural resource management by native Amazonians. In collaboration with the Kayapó Indians of A’Ukre of southeastern Amazonia,
we obtained a game harvest profile of over 1360 forest vertebrates consumed at this village over a 20-month period, including
743 mammals, 361 forest tortoises and 256 birds from a minimum of 42 game species. This amounted to a total of 13,775 kg of
game animals harvested over the entire study (mean = 26.2 kg d−1). We also obtained some 450 km of line transect census data of midsized to large-bodied vertebrates within the core hunting
catchment of this village and in an unhunted but otherwise comparable site upriver of A’Ukre. Population density estimates
of 16 of the 18 species censused were significantly depressed by hunting by central place foragers within the village catchment,
and a number of harvest-sensitive prey species showed clear evidence of local depletion. For the time being, however, we can
conclude that hunting was sustainable at the landscape scale largely because source-sink dynamics in the context of low village
catchment density is made possible by large surrounding tracts of primary forest that remain unharvested or underharvested. 相似文献
Rat liver mitochondria were stored at 0-4 degrees C for several days using an appropriate medium and energy source. The elimination of the majority of microsomes and lysosomes, that normally contaminate isolated mitochondria, had a positive effect in preservation of respiratory control, P:O ratio, and monoamine oxidase activity during long term storage. 相似文献
Monosodium glutamate (MSG) has been shown to alter several neuroendocrine functions in neonatally treated rats. To evaluate possible alterations in lipogenesis rate and lipoprotein lipase (LPL) activity, male and female rats were injected during the neonatal period with MSG or saline (controls). In male MSG rats, an increase in lipogenesis of liver and retroperitoneal adipose tissues was observed. Triton WR 1339 (an LPL inhibitor) administration decreased retroperitoneal lipogenesis in these animals. In female rats, MSG-treatment increased lipogenesis only in gonadal and retroperitoneal adipose tissues. No change was observed in hepatic lipogenesis and the Triton administration did not change retroperitoneal lipogenesis. LPL activity was increased in the gonadal and retroperitoneal adipose tissues in male and female MSG-treated rats. These data suggest that there is a specific sex-dependent response in the development of MSG-induced obesity. 相似文献