Genomic And Chemical Insights Into Biosurfactant Production By The Mangrove-derived Strain Bacillus Safensis Ccma-560.

Many Bacillus species can produce biosurfactant, although most of the studies on lipopeptide production by this genus have been focused on Bacillus subtilis. Surfactants are broadly used in pharmaceutical, food and petroleum industry, and biological surfactant shows some advantages over the chemical surfactants, such as less toxicity, production from renewable, cheaper feedstocks and development of novel recombinant hyperproducer strains. This study is aimed to unveil the biosurfactant metabolic pathway and chemical composition in Bacillus safensis strain CCMA-560. The whole genome of the CCMA-560 strain was previously sequenced, and with the aid of bioinformatics tools, its biosurfactant metabolic pathway was compared to other pathways of closely related species. Fourier transform infrared (FTIR) and high-resolution TOF mass spectrometry (MS) were used to characterize the biosurfactant molecule. B. safensis CCMA-560 metabolic pathway is similar to other Bacillus species; however, some differences in amino acid incorporation were observed, and chemical analyses corroborated the genetic results. The strain CCMA-560 harbours two genes flanked by srfAC and srfAD not present in other Bacillus spp., which can be involved in the production of the analogue gramicidin. FTIR and MS showed that B. safensis CCMA-560 produces a mixture of at least four lipopeptides with seven amino acids incorporated and a fatty acid chain with 14 carbons, which makes this molecule similar to the biosurfactant of Bacillus pumilus, namely, pumilacidin. This is the first report on the biosurfactant production by B. safensis, encompassing the investigation of the metabolic pathway and chemical characterization of the biosurfactant molecule.

Vaginal Epithelium And Microflora Characteristics In Women With Premature Ovarian Failure Under Hormone Therapy Compared To Healthy Women.

To evaluate some microbiological aspects of the vaginal flora and the vaginal trophism of women with premature ovarian failure (POF) in use of oral hormone therapy. A cross-sectional study with 36 women with POF under the age of 40 years using oral hormonal therapy. They were age matched with 36 women with normal gonadal function (control group). The characteristics of the vaginal epithelium were assessed through the hormonal vaginal cytology, vaginal pH measurement and vaginal health index to identify vaginal disturbances. Vaginal microflora was evaluated by the amine test, bacterioscopy (Nugent score) and culture for fungi to identify vaginal abnormal microflora and fungi infections. Despite the fact that there were no statistical significant differences related to the cytological aspects and pH measurements, it was found that the vaginal health index was highly superior in the control group than in the POF group (23.4 ± 1.8 vs 20.8 ± 3.5), p < 0.0001 despite both groups had trophic scores. There were no statistical significance differences regarding to vaginal microflora types and fungi infection. Oral hormone therapy for young women with POF seems to be good enough to reestablish the epithelium cells, vaginal pH and microflora.

Synchronous Oral Paracoccidioidomycosis And Pulmonary Tuberculosis In An Immunocompetent Patient.

Paracoccidioidomycosis (PCM) and tuberculosis (TB) are chronic granulomatous infectious diseases, in which the main form of contraction is through inhalation of the microorganism-Paracoccidioides brasiliensis and Mycobacterium tuberculosis. Oral involvement of PCM is observed in up to 70 % of the cases and usually presents clinically as ulcerations with granular surface showing tiny hemorrhagic areas. Oral presentation of TB is rare with prevalence smaller than 0.5 % of all cases. Clinical presentation of oral TB mainly consists of single ulcers with irregular limits and necrotic base. A 70-year-old immunocompetent man presented simultaneously oral PCM and pulmonary TB. Medical history revealed a previous diagnosis of pulmonary TB; however, even under treatment for TB, the patient remained with oral lesions and intense pulmonary fibrosis. The physician requested P. brasiliensis serological analysis, which resulted positive. Although the combination of PCM and TB has been reported in the literature, it is still considered an uncommon condition and their diagnosis may represent a challenge to healthcare professionals because of the similarity between their clinical and radiological presentations.

Chromobacterium Amazonense Sp. Nov. Isolated From Water Samples From The Rio Negro, Amazon, Brazil.

The taxonomic position of a bacterium isolated from water samples from the Rio Negro, in Amazon, Brazil, was determined by using a polyphasic approach. The organism formed a distinct phyletic line in the Chromobacterium 16S rRNA gene tree and had chemotaxonomic and morphological properties consistent with its classification in this genus. It was found to be closely related to Chromobacterium vaccinii DSM 25150(T) (98.6 % 16S rRNA gene similarity) and shared 98.5 % 16S rRNA gene similarity with Chromobacterium piscinae LGM 3947(T). DNA-DNA relatedness studies showed that isolate CBMAI 310(T) belongs to distinct genomic species. The isolate was readily distinguished from the type strain of these species using a combination of phenotypic and chemotaxonomic properties. Thus, based on genotypic and phenotypic data, it is proposed that isolate CBMAI 310(T) (=DSM 26508(T)) be classified in the genus Chromobacterium as the type strain of a novel species, namely, Chromobacterium amazonense sp. nov.

Temporal Auditory Processing And Phonological Awareness In Children With Benign Epilepsy With Centrotemporal Spikes.

The aim of this research was to analyze temporal auditory processing and phonological awareness in school-age children with benign childhood epilepsy with centrotemporal spikes (BECTS). Patient group (GI) consisted of 13 children diagnosed with BECTS. Control group (GII) consisted of 17 healthy children. After neurological and peripheral audiological assessment, children underwent a behavioral auditory evaluation and phonological awareness assessment. The procedures applied were: Gaps-in-Noise test (GIN), Duration Pattern test, and Phonological Awareness test (PCF). Results were compared between the groups and a correlation analysis was performed between temporal tasks and phonological awareness performance. GII performed significantly better than the children with BECTS (GI) in both GIN and Duration Pattern test (P < 0.001). GI performed significantly worse in all of the 4 categories of phonological awareness assessed: syllabic (P = 0.001), phonemic (P = 0.006), rhyme (P = 0.015) and alliteration (P = 0.010). Statistical analysis showed a significant positive correlation between the phonological awareness assessment and Duration Pattern test (P < 0.001). From the analysis of the results, it was concluded that children with BECTS may have difficulties in temporal resolution, temporal ordering, and phonological awareness skills. A correlation was observed between auditory temporal processing and phonological awareness in the suited sample.

Altered Urinary Sodium Excretion Response After Central Cholinergic And Adrenergic Stimulation Of Adult Spontaneously Hypertensive Rats.

In this study, we hypothesized that blunting of the natriuresis response to intracerebroventricularly (i.c.v.) microinjected cholinergic and adrenergic agonists is involved in the development of hypertension in spontaneously hypertensive rats (SHR). We evaluated the effect of i.c.v. injection of cholinergic and noradrenergic agonists, at increasing concentrations, and of muscarinic cholinergic and α1 and α2-adrenoceptor antagonists on blood pressure and urinary sodium handling in SHR, compared with age-matched Wistar Kyoto rats (WR). We confirmed that CCh and NE microinjected into the lateral ventricle (LV) of conscious rats leads to enhanced natriuresis. This response was associated with increased proximal and post-proximal sodium excretion accompanied by an unchanged rate of glomerular filtration. We showed that cholinergic-induced natriuresis in WR and SHR was attenuated by previous i.c.v. administration of atropine and was significantly lower in the hypertensive strain than in WR. In both groups the natriuretic effect of injection of noradrenaline into the LV was abolished by previous local injection of an α1-adrenoceptor antagonist (prazosin). Conversely, LV α2-adrenoceptor antagonist (yohimbine) administration potentiated the action of noradrenaline. The LV yohimbine pretreatment normalized urinary sodium excretion in SHR compared with age-matched WR. In conclusion, these are, as far as we are aware, the first results showing the importance of interaction of central cholinergic and/or noradrenergic receptors in the pathogenesis of spontaneous hypertension. These experiments also provide good evidence of the existence of a central adrenergic mechanism consisting of α1 and α2-adrenoceptors which works antagonistically on regulation of renal sodium excretion.

[comparative Study Between Fast And Slow Induction Of Propofol Given By Target-controlled Infusion: Expected Propofol Concentration At The Effect Site. Randomized Controlled Trial].

studies have shown that rate of propofol infusion may influence the predicted propofol concentration at the effect site (Es). The aim of this study was to evaluate the Es predicted by the Marsh pharmacokinetic model (ke0 0.26min(-1)) in loss of consciousness during fast or slow induction. the study included 28 patients randomly divided into two equal groups. In slow induction group (S), target-controlled infusion (TCI) of propofol with plasma, Marsh pharmacokinetic model (ke0 0.26min(-1)) with target concentration (Tc) at 2.0-μg.mL(-1) were administered. When the predicted propofol concentration at the effect site (Es) reached half of Es value, Es was increased to previous Es + 1μg.mL(-1), successively, until loss of consciousness. In rapid induction group (R), patients were induced with TCI of propofol with plasma (6.0μg.ml(-1)) at Es, and waited until loss of consciousness. in rapid induction group, Tc for loss of consciousness was significantly lower compared to slow induction group (1.67±0.76 and 2.50±0.56μg.mL(-1), respectively, p=0.004). the predicted propofol concentration at the effect site for loss of consciousness is different for rapid induction and slow induction, even with the same pharmacokinetic model of propofol and the same balance constant between plasma and effect site.

Nectar Robbery By A Hermit Hummingbird: Association To Floral Phenotype And Its Influence On Flowers And Network Structure.

Interactions between flowers and their visitors span the spectrum from mutualism to antagonism. The literature is rich in studies focusing on mutualism, but nectar robbery has mostly been investigated using phytocentric approaches focused on only a few plant species. To fill this gap, we studied the interactions between a nectar-robbing hermit hummingbird, Phaethornis ruber, and the array of flowers it visits. First, based on a literature review of the interactions involving  P. ruber, we characterized the association of floral larceny to floral phenotype. We then experimentally examined the effects of nectar robbing on nectar standing crop and number of visits of the pollinators to the flowers of Canna paniculata. Finally, we asked whether the incorporation of illegitimate interactions into the analysis affects plant-hummingbird network structure. We identified 97 plant species visited by P. ruber and found that P. ruber engaged in floral larceny in almost 30 % of these species. Nectar robbery was especially common in flowers with longer corolla. In terms of the effect on C. paniculata, the depletion of nectar due to robbery by P. ruber was associated with decreased visitation rates of legitimate pollinators. At the community level, the inclusion of the illegitimate visits of P. ruber resulted in modifications of how modules within the network were organized, notably giving rise to a new module consisting of P. ruber and mostly robbed flowers. However, although illegitimate visits constituted approximately 9 % of all interactions in the network, changes in nestedness, modularity, and network-level specialization were minor. Our results indicate that although a flower robber may have a strong effect on the pollination of a particular plant species, the inclusion of its illegitimate interactions has limited capacity to change overall network structure.

Reduction Of Oxidative Damage And Inflammatory Response In The Diaphragm Muscle Of Mdx Mice Using Iron Chelator Deferoxamine.

Oxidative stress and inflammatory processes strongly contribute to pathogenesis in Duchenne muscular dystrophy (DMD). Based on evidence that excess iron may increase oxidative stress and contribute to the inflammatory response, we investigated whether deferoxamine (DFX), a potent iron chelating agent, reduces oxidative stress and inflammation in the diaphragm (DIA) muscle of mdx mice (an experimental model of DMD). Fourteen-day-old mdx mice received daily intraperitoneal injections of DFX at a dose of 150 mg/kg body weight, diluted in saline, for 14 days. C57BL/10 and control mdx mice received daily intraperitoneal injections of saline only, for 14 days. Grip strength was evaluated as a functional measure, and blood samples were collected for biochemical assessment of muscle fiber degeneration. In addition, the DIA muscle was removed and processed for histopathology and Western blotting analysis. In mdx mice, DFX reduced muscle damage and loss of muscle strength. DFX treatment also resulted in a significant reduction of dystrophic inflammatory processes, as indicated by decreases in the inflammatory area and in NF-κB levels. DFX significantly decreased oxidative damage, as shown by lower levels of 4-hydroxynonenal and a reduction in dihydroethidium staining in the DIA muscle of mdx mice. The results of the present study suggest that DFX may be useful in therapeutic strategies to ameliorate dystrophic muscle pathology, possibly via mechanisms involving oxidative and inflammatory pathways.

Photodynamic Antimicrobial Effects Of Bis-indole Alkaloid Indigo From Indigofera Truxillensis Kunth (leguminosae).

Multidrug-resistant microbial infections represent an exponentially growing problem affecting communities worldwide. Photodynamic therapy is a promising treatment based on the combination of light, oxygen, and a photosensitizer that leads to reactive oxygen species production, such as superoxide (type I mechanism) and singlet oxygen (type II mechanism) that cause massive oxidative damage and consequently the host cell death. Indigofera genus has gained considerable interest due its mutagenic, cytotoxic, and genotoxic activity. Therefore, this study was undertaken to investigate the effect of crude extracts, alkaloidal fraction, and isolated substance derived from Indigofera truxillensis in photodynamic antimicrobial chemotherapy on the viability of bacteria and yeast and evaluation of mechanisms involved. Our results showed that all samples resulted in microbial photoactivation in subinhibitory concentration, with indigo alkaloid presenting a predominant photodynamic action through type I mechanism. The use of CaCl2 and MgCl2 as cell permeabilizing additives also increased gram-negative bacteria susceptibility to indigo.

Microsatellite Markers For Urochloa Humidicola (poaceae) And Their Transferability To Other Urochloa Species.

Urochloa humidicola is a warm-season grass commonly used as forage in the tropics and is recognized for its tolerance to seasonal flooding. This grass is an important forage species for the Cerrado and Amazon regions of Brazil. U. humidicola is a polyploid species with variable ploidy (6X-9X) and facultative apomixis with high phenotypic plasticity. However, this apomixis and ploidy, as well as the limited knowledge of the genetic basis of the germplasm collection, have constrained genetic breeding activities, yet microsatellite markers may enable a better understanding of the species' genetic composition. This study aimed to develop and characterize new polymorphic microsatellite molecular markers in U. humidicola and to evaluate their transferability to other Urochloa species. A set of microsatellite markers for U. humidicola was identified from two new enriched genomic DNA libraries: the first library was constructed from a single sexual genotype and the second from a pool of eight apomictic genotypes selected on the basis of previous results. Of the 114 loci developed, 72 primer pairs presented a good amplification product, and 64 were polymorphic among the 34 genotypes tested. The number of bands per simple sequence repeat (SSR) locus ranged from 1 to 29, with a mean of 9.6 bands per locus. The mean polymorphism information content (PIC) of all loci was 0.77, and the mean discrimination power (DP) was 0.87. STRUCTURE analysis revealed differences among U. humidicola accessions, hybrids, and other Urochloa accessions. The transferability of these microsatellites was evaluated in four species of the genus, U. brizantha, U. decumbens, U. ruziziensis, and U. dictyoneura, and the percentage of transferability ranged from 58.33% to 69.44% depending on the species. This work reports new polymorphic microsatellite markers for U. humidicola that can be used for breeding programs of this and other Urochloa species, including genetic linkage mapping, quantitative trait loci identification, and marker-assisted selection.

Towards A Deeper Understanding Of Structural Biomass Recalcitrance Using Phase-contrast Tomography.

The development of technological routes to convert lignocellulosic biomass to liquid fuels requires an in-depth understanding of the cell wall architecture of substrates. Essential pretreatment processes are conducted to reduce biomass recalcitrance and usually increase the reactive surface area. Quantitative three-dimensional information about both bulk and surface structural features of substrates needs to be obtained to expand our knowledge of substrates. In this work, phase-contrast tomography (PCT) was used to gather information about the structure of a model lignocellulosic biomass (piassava fibers). The three-dimensional cellular organization of piassava fibers was characterized by PCT using synchrotron radiation. This technique enabled important physical features that describe the substrate piassava fibers to be visualized and quantified. The external surface area of a fiber and internal surface area of the pores in a fiber could be determined separately. More than 96% of the overall surface area available to enzymes was in the bulk substrate. The pore surface area and length exhibited a positive linear relationship, where the slope of this relationship depended on the plant tissue. We demonstrated that PCT is a powerful tool for the three-dimensional characterization of the cell wall features related to biomass recalcitrance. Original and relevant quantitative information about the structural features of the analyzed material were obtained. The data obtained by PCT can be used to improve processing routes to efficiently convert biomass feedstock into sugars.

New Interaction Partners For Nek4.1 And Nek4.2 Isoforms: From The Dna Damage Response To Rna Splicing.

Neks are serine-threonine kinases that are similar to NIMA, a protein found in Aspergillus nidulans which is essential for cell division. In humans there are eleven Neks which are involved in different biological functions besides the cell cycle control. Nek4 is one of the largest members of the Nek family and has been related to the primary cilia formation and in DNA damage response. However, its substrates and interaction partners are still unknown. In an attempt to better understand the role of Nek4, we performed an interactomics study to find new biological processes in which Nek4 is involved. We also described a novel Nek4 isoform which lacks a region of 46 amino acids derived from an insertion of an Alu sequence and showed the interactomics profile of these two Nek4 proteins. Isoform 1 and isoform 2 of Nek4 were expressed in human cells and after an immunoprecipitation followed by mass spectrometry, 474 interacting proteins were identified for isoform 1 and 149 for isoform 2 of Nek4. About 68% of isoform 2 potential interactors (102 proteins) are common between the two Nek4 isoforms. Our results reinforce Nek4 involvement in the DNA damage response, cilia maintenance and microtubule stabilization, and raise the possibility of new functional contexts, including apoptosis signaling, stress response, translation, protein quality control and, most intriguingly, RNA splicing. We show for the first time an unexpected difference between both Nek4 isoforms in RNA splicing control. Among the interacting partners, we found important proteins such as ANT3, Whirlin, PCNA, 14-3-3ε, SRSF1, SRSF2, SRPK1 and hNRNPs proteins. This study provides new insights into Nek4 functions, identifying new interaction partners and further suggests an interesting difference between isoform 1 and isoform 2 of this kinase. Nek4 isoform 1 may have similar roles compared to other Neks and these roles are not all preserved in isoform 2. Besides, in some processes, both isoforms showed opposite effects, indicating a possible fine controlled regulation.

The C-terminal Region Of The Human P23 Chaperone Modulates Its Structure And Function.

The p23 protein is a chaperone widely involved in protein homeostasis, well known as an Hsp90 co-chaperone since it also controls the Hsp90 chaperone cycle. Human p23 includes a β-sheet domain, responsible for interacting with Hsp90; and a charged C-terminal region whose function is not clear, but seems to be natively unfolded. p23 can undergo caspase-dependent proteolytic cleavage to form p19 (p231-142), which is involved in apoptosis, while p23 has anti-apoptotic activity. To better elucidate the function of the human p23 C-terminal region, we studied comparatively the full-length human p23 and three C-terminal truncation mutants: p23₁₋₁₁₇; p23₁₋₁₃₁ and p23₁₋₁₄₂. Our data indicate that p23 and p19 have distinct characteristics, whereas the other two truncations behave similarly, with some differences to p23 and p19. We found that part of the C-terminal region can fold in an α-helix conformation and slightly contributes to p23 thermal-stability, suggesting that the C-terminal interacts with the β-sheet domain. As a whole, our results suggest that the C-terminal region of p23 is critical for its structure-function relationship. A mechanism where the human p23 C-terminal region behaves as an activation/inhibition module for different p23 activities is proposed.