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1.
This notes pursues the theme introduced in the first Notes and Observations publication: the effectiveness of biofeedback in treatment of the elderly. Current clinical results in progress are reported for a 76-year-old female hypertensive whose blood pressure has to date been lowered from 190/90 to 160/82 by means of thermal biofeedback in conjunction with progressive relaxation. These results are contrasted with reported failures in the headache study of elderly patients (Blanchard, Andrasik, Evans, & Hillhouse 1985). Results of this study are reinterpreted in terms of biofeedback modality rather than age of subjects.  相似文献   
2.
Fungal xylanases have been widely studied and various production methods have been proposed using submerged and solid-state fermentation. This class of enzyme is used to supplement cellulolytic enzyme cocktails in order to enhance the enzymatic hydrolysis of plant cell walls. The present work investigates the production of xylanase and other accessory enzymes by a recently isolated endophytic Aspergillus niger DR02 strain, using the pentose-rich liquor from hydrothermal pretreatment of sugarcane bagasse as carbon source. Batch and fed-batch submerged cultivation approaches were developed in order to minimize the toxicity of the liquor and increase enzyme production. Maximum xylanase activities obtained were 458.1 U/mL for constant fed-batch, 428.1 U/mL for exponential fed-batch, and 264.37 U/mL for pulsed fed-batch modes. The results indicated that carbon-limited fed-batch cultivation can reduce fungal catabolite repression, as well as overcome possible negative effects of toxic compounds present in the pentose-rich liquor. Enzymatic panel and mass spectrometric analyses of the fed-batch A. niger secretome showed high levels of xylanolytic enzymes (GH10, GH11, and GH62 Cazy families), together with cellobiohydrolase (G6 and GH7), β-glucosidase, β-xylosidase (GH3), and feruloyl esterase (CE1) accessory enzyme activities. The yields of glucose and xylose from enzymatic hydrolysis of hydrothermally pretreated sugarcane bagasse increased by 43.7 and 65.3%, respectively, when a commercial cellulase preparation was supplemented with the A. niger DR02 constant fed-batch enzyme complex.  相似文献   
3.
There is some evidence that dogs can be naturally infected by Paracoccidioides brasiliensis in endemic areas of paracoccidioidomycosis. In order to evaluate canine infection with this fungus, a survey with 149 urban and 126 rural dogs was carried out using ELISA and intradermal tests with the gp43 antigen of P. brasiliensis in Uberaba, Minas Gerais state of Brazil. Forty-one out of 149 urban dogs were euthanatized and had their lungs, liver and spleen removed. One slice from each viscera was processed for histopathological examination and the remaining was homogenized and then cultivated on mycobiotic agar at room temperature and Fava-Netto medium at 35°C and observed for 12 weeks. Of urban dogs, 75 (50.3%) were small adult females, 56 (36%) were strays, while 93 (64%) had been donated to the municipal zoonosis control center. Nine (6.2%) had a positive intradermal test without statistical differences regarding gender, race, nutritional status or origin. No colonies with microscopic or morphology appearances resembling P. brasiliensis were isolated, nor granulomatous process or fungal structures were observed from histopathological examination. Eighty (53.6%) of the urban dogs presented seroreactivity, without statistical differences regarding gender, race, nutritional state, origin, or positive intradermal test. Of 126 rural dogs, 102 (80.5%) presented antibodies against gp43 antigen, and this was statistically significant in relation to the reactivity detected in urban dogs (P = 0.0001). Thus, dogs are commonly infected with P. brasiliensis, but they probably present natural resistance to develop paracoccidioidomycosis.  相似文献   
4.
The ecological niche or exact habitat of the fungus Paracoccidioides brasiliensis is not known, and few isolates have been obtained from the environment. In this study, ten isolates were analyzed with respect to antigenic composition, serology, pathogenicity, and molecular aspects. Gp43 is considered to be the molecular basis for the serodiagnosis of paracoccidioidomycosis; however, in this study only six of the environmental isolates secreted this molecule (four in great amounts and two in small amounts). Other molecules were also produced. When exoantigens from these isolates were tested using immunodiffusion, only four preparations were positive by ID tests. However, when these exoantigens were tested by ELISA, all of them except one were able to detect anti-P. brasiliensis antibodies. In Western blot assays, these exoantigens showed different reactivities. Isolates that secreted gp43 presented positive reactions for this molecule, and isolates that did not secrete gp43 gave positive reactions for other minor molecules. RAPD analysis revealed that there is great genetic variation between these environmental isolates. These isolates were non-pathogenic: no mortality was observed among the inoculated mice during an 18-month follow-up period.  相似文献   
5.

Background  

We study the usage of specific peptide platforms in protein composition. Using the pentapeptide as a unit of length, we find that in the universal proteome many pentapeptides are heavily repeated (even thousands of times), whereas some are quite rare, and a small number do not appear at all. To understand the physico-chemical-biological basis underlying peptide usage at the proteomic level, in this study we analyse the energetic costs for the synthesis of rare and never-expressed versus frequent pentapeptides. In addition, we explore residue bulkiness, hydrophobicity, and codon number as factors able to modulate specific peptide frequencies. Then, the possible influence of amino acid composition is investigated in zero- and high-frequency pentapeptide sets by analysing the frequencies of the corresponding inverse-sequence pentapeptides. As a final step, we analyse the pentadecamer oligodeoxynucleotide sequences corresponding to the never-expressed pentapeptides.  相似文献   
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7.
The spatial and temporal distribution of organisms is a fundamental aspect of biological communities. The present study focused on three remnants of arboreal Caatinga in northeastern Brazil between May, 2009 and April, 2010. A total of 627 euglossine males were captured in traps baited with artificial aromatic compounds. The specimens belonged to 14 species and four genera: Euglossa Latreille, Eulaema Lepeletier, Eufriesea Cockerell, and Exaerete Hoffmannsegg. Eulaema nigrita Lepeletier (41.6), Euglossa carolina Nemésio (15.3%), Eulaema marcii Nemésio (13.6%), and Euglossa melanotricha Moure (12.8%) were the most common species sampled. The distribution of collected specimens per fragment was as follows: Braúna (280?ha)??259 individuals belonging to 14 species; Cambuí (179?ha)??161 individuals from eight species; and Pindoba (100?ha)??207 individuals represented by seven species. Braúna had the highest diversity (H???=?1.91) and estimated species richness. The largest fragment was the main source of the observed variation in species richness and abundance, indicating a non-random pattern of spatial distribution. The analysis of environmental factors indicated that seasonal variation in these factors was the principal determinant of species occurrence and abundance.  相似文献   
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9.
ABSTRACT

Potent second-generation anticoagulant rodenticides such as brodifacoum have been used as more effective alternatives to first-generation anticoagulants, such as warfarin. A combination of diphacinone at 0.005% and cholecalciferol at 0.06% produces a slow-acting bait that is effective at killing possums (Trichosurus vulpecula) and rodents. Cage trials with groups of possums and ship rats (Rattus rattus) achieved a mortality of 87% and 86% for possums and ship rats, respectively. Two field trials, each 200 hectares in size, targeting possums, ship rats and mice achieved an average reduction in the abundance of 94% for possums, 94% for ship rats and 80% for mice. The combination of diphacinone and cholecalciferol appears effective and has a favourable risk profile compared with second-generation anticoagulant rodenticides, such as brodifacoum. Approval of this new bait by the New Zealand Environmental Protection Agency was granted in 2018 and final registration obtained from the Ministry of Primary Industries in 2019.  相似文献   
10.
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