Background and aims
The endophytic diazotrophic strain CBAmC of
Nitrospirillum amazonense
has been reported as a plant growth promoter of sugarcane variety RB867515 when grown under field conditions. ...The present work aimed to assess the influence of apoplast fluid from RB867515 on the transcriptomic and proteomic profiles of CBAmC cultured
in vitro
.
Methods
RNA-Seq in Ion Proton™ and ESI-LC-MS/MS peptide analysis were used to evaluate the transcriptomic and proteomic profiles, respectively, of CBAmC exposed for 2 h to the sugarcane apoplast fluid.
Results
The bacterial transcriptomic and proteomic profiles were well correlated. The overall response of CBAmC to the apoplast fluid included overexpression of defense systems against reactive oxygen species (ROS) and osmotic stress, RND efflux pumps for toxic compounds, Sec and Tat secretory systems, and assimilative metabolism of iron. In contrast, active transporters of organic compounds, chemotaxis system and flagellum structure were underexpressed.
Conclusions
The bacterial metabolic pathways / functions activated in response to the sugarcane apoplast fluid are most likely related to its adaptation to the peculiar characteristics of the fluid. The activation of some of those functions could be determinant for its adaptation to the sugarcane apoplastic niche, and perhaps be involved in the previously observed effect of promoting plant growth.
Feedlot cattle are usually adapted to high-concentrate diets containing sodium monensin (MON) in more than 14 days. However, considering that the dry matter intake DMI is usually lower during ...adaptation when compared to the finishing period, the use of MON during adaptation may decrease even further the DMI, and virginiamycin (VM) may be an alternative. This study was designed to investigate the effects of shortening the adaptation length from 14 to 9 or 6 days on ruminal metabolism, feeding behavior, and nutrient digestibility of Nellore cattle fed high-concentrate diets containing only VM as the sole feed additive. The experimental design was a 5 × 5 Latin square, where each period lasted 21 days. Five 17 mo-old Nellore yearling bulls were used (415 ± 22 kg of body weight), which were assigned to five treatments: (1) MON (30 mg/kg) and adaptation for 14 days; (2) MON (30 mg/kg) + VM (25 mg/kg) and adaptation for 14 days; (3) VM (25 mg/kg) and adaptation for 14 days; (4) VM (25 mg/kg) and adaptation for 9 days, and (5) VM (25 mg/kg) and adaptation for 6 days. A quadratic effect for adaptation length when only VM was fed was observed for mean pH (
= 0.03), duration of pH below 5.2 (
= 0.01) and 6.2 (
= 0.01), where cattle consuming VM adapted for 9 days had higher mean pH and shorter period of pH below 5.2 and 6.2. Cattle that consumed only MON had a lower concentration of butyrate (
= 0.02) and a higher concentration of propionate (
= 0.04) when compared to those consuming VM and adapted for 14 days. As the adaptation length decreased for animals consuming only VM, the rumen degradability of dry matter (
< 0.01), neutral detergent fiber (
< 0.01), and starch (
< 0.01) decreased; however, protozoa numbers of
and total protozoa increased. It is not recommended to shorten the adaptation length of these animals to either 6 or 9 days without negatively impacting nutrient disappearance and ruminal fermentation patterns.
We report herein the synthesis and trypanocidal profile of new (E)-cinnamic N-acylhydrazones (NAHs) designed by exploiting molecular hybridization between the potent cruzain inhibitors ...(E)-1-(benzod1,3dioxol-5-yl)-3-(4-bromophenyl)prop-2-en-1-one and (E)-3-hydroxy-N′-((2-hydroxynaphthalen-1-yl)methylene)-7-methoxy-2-naphthohydrazide. These derivatives were evaluated against both amastigote and trypomastigote forms of Trypanosoma cruzi and lead us to identify two compounds that were approximately two times more active than the reference drug, benznidazole, and with good cytotoxic index. Although designed as cruzain inhibitors, the weak potency displayed by the best cinnamyl NAH derivatives indicated that another mechanism of action was likely responsible for their trypanocide action.
Display omitted Novel cinnamic-N-acylhydrazones (NAHs) with potent trypanocide profile and adequate cytotoxicity index were described. Two of these NAH compounds showed to be more effective than the standard drug benznidazole against trypomastigote forms of T. cruzi.
► New (E)-cinnamic N-acylhydrazones (NAHs) were synthesized and evaluated as trypanocide agents. ► (E)-Cinnamic NAH was designed through molecular hybridization of potent cruzain inhibitors. ► (E)-Cinnamic NAH presenting 2-hydroxyphenyl group attached to imine unit are potent trypanocides. ► (E)-Cinnamic NAH has 2-fold higher potency than benznidazole against trypomastigote forms of T. cruzi. ► (E)-Cinnamic N-acylhydrazones have adequate cytotoxicity profile against mammalian cells.
Feedlot cattle are usually adapted to high-concentrate diets containing sodium monensin (MON) in more than 14 days. However, for finishing diets with lower energy content, the use of MON during ...adaptation may hold dry matter intake (DMI), and virginiamycin (VM) may be an alternative. This study was designed to determine the potential of shortening the adaptation of Nellore cattle to high-concentrate diets using only VM as a sole feed additive relative to feedlot performance, feeding behavior, and ruminal and cecum morphometrics. The experiment was designed as a completely randomized block replicated six times (four animals/pen) in which 120 Nellore bulls (390.4 ± 19.0 kg) were fed in 30 pens for 111 days according to the following treatments: (1) MON and adaptation for 14 days (MON14), (2) MON + VM and adaptation for 14 days (MONVM14), (3) VM and adaptation for 14 days (VM14), (4) VM and adaptation for 9 days (VM9), and (5) VM and adaptation for 6 days (VM6). At the end of the adaptation, 30 animals (
n
= 1 per pen) were randomly slaughtered for rumen and cecum evaluations. The remaining 90 bulls were harvested at the end of the study. No effects of treatments were observed (
P
< 0.10) for final body weight, average daily gain (ADG), and hot carcass weight (HCW). Cattle fed VM14 presented a greater (
P
≤ 0.03) DMI, expressed as percent of body weight (BW), than animals fed either MON14 or MONVM14; however, cattle fed either MON14 or MONVM14 improved (
P
≤ 0.02) the gain-to-feed ratio (G/F) by 10.4 or 8.1%, respectively, when compared to bulls fed VM14. Bulls fed VM14 had smaller (
P
< 0.05) papillae area (0.34 vs. 0.42 cm
2
) and rumen absorptive surface area (28.9 vs. 33.8 cm
2
) than those fed MON14. The shortening of the adaptation period linearly decreased the 12th rib fat (
P
= 0.02) and biceps femoris fat daily gain (
P
= 0.02) of Nellore bulls fed only VM, which linearly decreased the final biceps femoris fat thickness (
P
< 0.01). Feedlot cattle fed VM as a sole feed additive should not be adapted to high-concentrate diets in less than 14 days. Regardless of either adaptation length or feed additive, feedlot cattle need at least 14 days to adapt to finishing diets.
We have investigated the chemical composition and the antibacterial activity of the essential oil of Dysphania ambrosioides (L.) Mosyakin & Clemants (Chenopodiaceae) (DA‐EO) against a representative ...panel of cariogenic bacteria. We have also assessed the in vitro schistosomicidal effects of DA‐EO on Schistosoma mansoni and its cytotoxicity to GM07492‐A cells in vitro. Gas chromatography (GC) and gas chromatography‐mass spectrometry (GC/MS) revealed that the monoterpenes cis‐piperitone oxide (35.2%), p‐cymene (14.5%), isoascaridole (14.1%), and α‐terpinene (11.6%) were identified by as the major constituents of DA‐EO. DA‐EO displayed weak activity against Streptococcus sobrinus and Enterococcus faecalis (minimum inhibitory concentration (MIC) = 1000 μg/ml). On the other hand, DA‐EO at 25 and 12.5 μg/ml presented remarkable schistosomicidal action in vitro and killed 100% of adult worm pairs within 24 and 72 h, respectively. The LC50 values of DA‐EO were 6.50 ± 0.38, 3.66 ± 1.06, and 3.65 ± 0.76 μg/ml at 24, 48, and 72 h, respectively. However, DA‐EO at concentrations higher than 312.5 μg/ml significantly reduced the viability of GM07492‐A cells (IC50 = 207.1 ± 4.4 μg/ml). The selectivity index showed that DA‐EO was 31.8 times more toxic to the adult S. mansoni worms than GM07492‐A cells. Taken together, these results demonstrate the promising schistosomicidal potential of the essential oil of Dysphania ambrosioides.
The purpose of this study was to investigate the influence of gutta-percha solvents on the bond strength of fiberglass post to root canal dentin. Forty bovine incisors were decoronated, prepared, ...filled, and randomly distributed into four groups (n = 10) according to the gutta-percha solvent used: control, xylene, eucalyptol and orange oil. After root canal treatment, the posts were cemented into the prepared root canals using a resin-based cement. A micro push-out test was executed, and the patterns of failure were assessed with microscopy. The data were analyzed using two-way ANOVA followed by Tukey’s test. The control group exhibited greater bond strength compared to the eucalyptol group in the cervical and middle thirds of the root (P < 0.05); however, it did not differ significantly from the xylene and orange oil groups (P > 0.05). No difference was observed in the values of the xylene, orange oil, and eucalyptol groups (P > 0.05). The cervical third had higher values than the apical third for all tested solvents (P < 0.05). Adhesive failure between resin cement and dentin was the most frequent type of failure. The use of xylene and orange oil as gutta-percha solvents did not influence the bond strength of fiberglass posts to root canal dentin. (J Oral Sci 56, 105-112, 2014)
Social support has a strong impact on individuals, not least on older individuals with health problems. A lack of support network and poor family or social relations may be crucial in later life, and ...represent risk factors for elder abuse. This study focused on the associations between social support, demographics/socio-economics, health variables and elder mistreatment.
The cross-sectional data was collected by means of interviews or interviews/self-response during January-July 2009, among a sample of 4,467 not demented individuals aged 60-84 years living in seven European countries (Germany, Greece, Italy, Lithuania, Portugal, Spain, and Sweden).
Multivariate analyses showed that women and persons living in large households and with a spouse/partner or other persons were more likely to experience high levels of social support. Moreover, frequent use of health care services and low scores on depression or discomfort due to physical complaints were indicators of high social support. Low levels of social support were related to older age and abuse, particularly psychological abuse.
High levels of social support may represent a protective factor in reducing both the vulnerability of older people and risk of elder mistreatment. On the basis of these results, policy makers, clinicians and researchers could act by developing intervention programmes that facilitate friendships and social activities in old age.
Rainforest aquatic ecosystems include complex habitats with scarce information on their unicellular eukaryote diversity and community structure. We have investigated the diversity of ciliates in ...freshwater and brackish environments along the Brazilian Atlantic Forest, based on the hypervariable V4 region of the 18S-rDNA obtained by high-throughput DNA sequencing. Our analyses detected 409 ciliate taxonomic units (OTUs), mostly attributed to the classes Oligohymenophorea and Spirotrichea. A total of 11 classes, 12 subclasses, 112 genera, and 144 species were reported. We found the following: (a) the ciliate communities are more diverse in freshwater- than in Atlantic Forest-associated brackish environments; (b) the ciliate communities are composed by a small amount of highly abundant OTUs, but a high number of low-abundant or rare OTUs; (c) nearly one-third of the ciliate OTUs share less than 97% sequence identity to reference sequences and (d) phylogenetic inference supports the hypothesis that the V4 region of the Ciliophora 18S-rDNA is a suitable marker for accurate evolutionary inferences at class level. Our results showed that a considerable fraction of the HTS-detected diversity of ciliates from Brazilian Atlantic Forest is not represented in the currently available molecular databases.
In this work, a search for antimicrobial agents against multi-drug resistant (MDR) bacteria was undertaken. It involved two natural diterpenes of different basic skeletons, named ent-kaurenoic acid ...and ent-pimaradienoic acid, that were used as precursors to access 28 semi-synthetic derivatives that were also submitted to biological assays. All 30 substances were assayed against a set of seven clinically isolated MDR bacteria, including three Staphylococcus aureus strains. Results classified both natural compounds as promising bactericidal antimicrobial agents against these MDR bacteria, especially for their performance in time-kill curve assay, improving on the positive control vancomycin. Moreover, di-hydro ent-pimaradienoic acid, obtained as one of the derivatives, also displayed promising minimum inhibitory concentration (MIC) values against the microorganism set, proving optimum activity against S. aureus strains. Thereby, this work also yielded a promising semi-synthetic bacteriostatic antimicrobial agent against MDR S. aureus. Furthermore, the study was carried out with 30 structures in order to verify the veracity and scope of Urzúa’s hypothesis about the structure-activity relationship between diterpenes and antimicrobial action. Our results are 93% in agreement with this hypothesis.
A set of seven diterpenes, three kauranes and four trachylobanes, isolated from the African plant Psiadia punctulata were assayed against Mycobacterium tuberculosis and reached activity comparable ...with cycloserine, a second line drug used to treat tuberculosis (TB). Several structural properties of those diterpenes, such as lipophilicity, HOMO and LUMO energies, charge density, and intramolecular hydrogen bond (IHB) formation, were obtained by theoretical calculations and compared with their activities. Peculiar correlations were observed, especially between activity, lipophilicity and IHB formation.
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