Sargassum Filipendula Alginate From Brazil: Seasonal Influence And Characteristics.

The aim of this work is focused on the extraction and characterization of the Brazilian seaweed Sargassum filipendula alginate. Alginates obtained at different seasons were characterized by liquid state nuclear magnetic resonance spectroscopy and scanning electron microscopy. The alginate extraction efficiency was about 20%. Different seasons of the year and different stages in the life cycle of Sargassum sp. in southeastern Brazil influenced the M/G and, consequently, the technological properties of extracted alginates.

Cluster Analysis To Identify Elderly People's Profiles: A Healthcare Strategy Based On Frailty Characteristics.

The new social panorama resulting from aging of the Brazilian population is leading to significant transformations within healthcare. Through the cluster analysis strategy, it was sought to describe the specific care demands of the elderly population, using frailty components. Cross-sectional study based on reviewing medical records, conducted in the geriatric outpatient clinic, Hospital de Clínicas, Universidade Estadual de Campinas (Unicamp). Ninety-eight elderly users of this clinic were evaluated using cluster analysis and instruments for assessing their overall geriatric status and frailty characteristics. The variables that most strongly influenced the formation of clusters were age, functional capacities, cognitive capacity, presence of comorbidities and number of medications used. Three main groups of elderly people could be identified: one with good cognitive and functional performance but with high prevalence of comorbidities (mean age 77.9 years, cognitive impairment in 28.6% and mean of 7.4 comorbidities); a second with more advanced age, greater cognitive impairment and greater dependence (mean age 88.5 years old, cognitive impairment in 84.6% and mean of 7.1 comorbidities); and a third younger group with poor cognitive performance and greater number of comorbidities but functionally independent (mean age 78.5 years old, cognitive impairment in 89.6% and mean of 7.4 comorbidities). These data characterize the profile of this population and can be used as the basis for developing efficient strategies aimed at diminishing functional dependence, poor self-rated health and impaired quality of life.

Effects Of High Pressure Homogenization On The Activity, Stability, Kinetics And Three-dimensional Conformation Of A Glucose Oxidase Produced By Aspergillus Niger.

High pressure homogenization (HPH) is a non-thermal method, which has been employed to change the activity and stability of biotechnologically relevant enzymes. This work investigated how HPH affects the structural and functional characteristics of a glucose oxidase (GO) from Aspergillus niger. The enzyme was homogenized at 75 and 150 MPa and the effects were evaluated with respect to the enzyme activity, stability, kinetic parameters and molecular structure. The enzyme showed a pH-dependent response to the HPH treatment, with reduction or maintenance of activity at pH 4.5-6.0 and a remarkable activity increase (30-300%) at pH 6.5 in all tested temperatures (15, 50 and 75°C). The enzyme thermal tolerance was reduced due to HPH treatment and the storage for 24 h at high temperatures (50 and 75°C) also caused a reduction of activity. Interestingly, at lower temperatures (15°C) the activity levels were slightly higher than that observed for native enzyme or at least maintained. These effects of HPH treatment on function and stability of GO were further investigated by spectroscopic methods. Both fluorescence and circular dichroism revealed conformational changes in the molecular structure of the enzyme that might be associated with the distinct functional and stability behavior of GO.

Impact Of Chemical Changes On The Sensory Characteristics Of Coffee Beans During Storage.

Sensory changes during the storage of coffee beans occur mainly due to lipid oxidation and are responsible for the loss of commercial value. This work aimed to verify how sensory changes of natural coffee and pulped natural coffee are related to the oxidative processes during 15 months of storage. During this period, changes in the content of free fatty acids (1.4-3.8 mg/g oil), TBARS values (8.8-10.2 nmol MDA/g), and carbonyl groups (2.6-3.5 nmol/mg of protein) occurred. The intensity of rested coffee flavour in the coffee brew increased (2.1-6.7) and 5-caffeoylquinic acid concentration decreased (5.2-4.6g/100g). Losses were also observed in seed viability, colour of the beans and cellular structure. All the results of the chemical analyses are coherent with the oxidative process that occurred in the grains during storage. Therefore, oxidation would be also responsible for the loss of cellular structure, seed viability and sensory changes.

Anatomical Study Of Minor Alterations In Neonate Vocal Folds.

Minor structural alterations of the vocal fold cover are frequent causes of voice abnormalities. They may be difficult to diagnose, and are expressed in different manners. Cases of intracordal cysts, sulcus vocalis, mucosal bridge, and laryngeal micro-diaphragm form the group of minor structural alterations of the vocal fold cover investigated in the present study. The etiopathogenesis and epidemiology of these alterations are poorly known. To evaluate the existence and anatomical characterization of minor structural alterations in the vocal folds of newborns. 56 larynxes excised from neonates of both genders were studied. They were examined fresh, or defrosted after conservation via freezing, under a microscope at magnifications of 25× and 40×. The vocal folds were inspected and palpated by two examiners, with the aim of finding minor structural alterations similar to those described classically, and other undetermined minor structural alterations. Larynges presenting abnormalities were submitted to histological examination. Six cases of abnormalities were found in different larynges: one (1.79%) compatible with a sulcus vocalis and five (8.93%) compatible with a laryngeal micro-diaphragm. No cases of cysts or mucosal bridges were found. The observed abnormalities had characteristics similar to those described in other age groups. Abnormalities similar to sulcus vocalis or micro-diaphragm may be present at birth.

A New Platinum Complex With Tryptophan: Synthesis, Structural Characterization, Dft Studies And Biological Assays In Vitro Over Human Tumorigenic Cells.

A new platinum(II) complex with the amino acid L-tryptophan (trp), named Pt-trp, was synthesized and characterized. Elemental, thermogravimetric and ESI-QTOF mass spectrometric analyses led to the composition [Pt(C11H11N2O2)2]⋅6H2O. Infrared spectroscopic data indicate the coordination of trp to Pt(II) through the oxygen of the carboxylate group and also through the nitrogen atom of the amino group. The (13)C CP/MAS NMR spectroscopic data confirm coordination through the oxygen atom of the carboxylate group, while the (15)N CP/MAS NMR data confirm coordination of the nitrogen of the NH2 group to the metal. Density functional theory (DFT) studies were applied to evaluate the cis and trans coordination modes of trp to platinum(II). The trans isomer was shown to be energetically more stable than the cis one. The Pt-trp complex was evaluated as a cytotoxic agent against SK-Mel 103 (human melanoma) and Panc-1 (human pancreatic carcinoma) cell lines. The complex was shown to be cytotoxic over the considered cells.

Structural And Biomechanical Changes In The Achilles Tendon After Chronic Treatment With Statins.

Cases of tendinopathy and tendon ruptures have been reported as side effects associated with statin therapy. This work assessed possible changes in the structural and biomechanical properties of the tendons after chronic treatment with statins. Wistar rats were divided into the following groups: treated with atorvastatin (A-20 and A-80), simvastatin (S-20 and S-80) and the group that received no treatment (C). The doses of statins were calculated using allometric scaling, based on the doses of 80 mg/day and 20 mg/day recommended for humans. The morphological aspect of the tendons in A-20, S-20 and S-80 presented signals consistent with degeneration. Both the groups A-80 and S-80 showed a less pronounced metachromasia in the compression region of the tendons. Measurements of birefringence showed that A-20, A-80 and S-80 groups had a lower degree of organization of the collagen fibers. In all of the groups treated with statins, the thickness of the epitenon was thinner when compared to the C group. In the biomechanical tests the tendons of the groups A-20, A-80 and S-20 were less resistant to rupture. Therefore, statins affected the organization of the collagen fibers and decreased the biomechanical strength of the tendons, making them more predisposed to ruptures.

Kinase Inhibitor Profile For Human Nek1, Nek6, And Nek7 And Analysis Of The Structural Basis For Inhibitor Specificity.

Human Neks are a conserved protein kinase family related to cell cycle progression and cell division and are considered potential drug targets for the treatment of cancer and other pathologies. We screened the activation loop mutant kinases hNek1 and hNek2, wild-type hNek7, and five hNek6 variants in different activation/phosphorylation statesand compared them against 85 compounds using thermal shift denaturation. We identified three compounds with significant Tm shifts: JNK Inhibitor II for hNek1(Δ262-1258)-(T162A), Isogranulatimide for hNek6(S206A), andGSK-3 Inhibitor XIII for hNek7wt. Each one of these compounds was also validated by reducing the kinases activity by at least 25%. The binding sites for these compounds were identified by in silico docking at the ATP-binding site of the respective hNeks. Potential inhibitors were first screened by thermal shift assays, had their efficiency tested by a kinase assay, and were finally analyzed by molecular docking. Our findings corroborate the idea of ATP-competitive inhibition for hNek1 and hNek6 and suggest a novel non-competitive inhibition for hNek7 in regard to GSK-3 Inhibitor XIII. Our results demonstrate that our approach is useful for finding promising general and specific hNekscandidate inhibitors, which may also function as scaffolds to design more potent and selective inhibitors.

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.

Molecularly Imprinted Solid Phase Extraction Of Fluconazole From Pharmaceutical Formulations.

This work encompasses a direct and coherent strategy to synthesise a molecularly imprinted polymer (MIP) capable of extracting fluconazole from its sample. The MIP was successfully prepared from methacrylic acid (functional monomer), ethyleneglycoldimethacrylate (crosslinker) and acetonitrile (porogenic solvent) in the presence of fluconazole as the template molecule through a non-covalent approach. The non-imprinted polymer (NIP) was prepared following the same synthetic scheme, but in the absence of the template. The data obtained from scanning electronic microscopy, infrared spectroscopy, thermogravimetric and nitrogen Brunauer-Emmett-Teller plot helped to elucidate the structural as well as the morphological characteristics of the MIP and NIP. The application of MIP as a sorbent was demonstrated by packing it in solid phase extraction cartridges to extract fluconazole from commercial capsule samples through an offline analytical procedure. The quantification of fluconazole was accomplished through UPLC-MS, which resulted in LOD≤1.63×10(-10) mM. Furthermore, a high percentage recovery of 91±10% (n=9) was obtained. The ability of the MIP for selective recognition of fluconazole was evaluated by comparison with the structural analogues, miconazole, tioconazole and secnidazole, resulting in percentage recoveries of 51, 35 and 32%, respectively.

Chemical And Structural Analyses Of Titanium Plates Retrieved From Patients.

The aim of this study was to evaluate the microscopic structure and chemical composition of titanium bone plates and screws retrieved from patients with a clinical indication and to relate the results to the clinical conditions associated with the removal of these devices. Osteosynthesis plates and screws retrieved from 30 patients between January 2010 and September 2013 were studied by metallographic, gas, and energy dispersive X-ray (EDX) analyses and the medical records of these patients were reviewed. Forty-eight plates and 238 screws were retrieved. The time elapsed between plate and screw insertion and removal ranged between 11 days and 10 years. Metallographic analysis revealed that all the plates were manufactured from commercially pure titanium (CP-Ti). The screw samples analyzed consisted of Ti-6Al-4V alloy, except four samples, which consisted of CP-Ti. Titanium plates studied by EDX analysis presented greater than 99.7% titanium by mass. On gas analysis of Ti-6Al-4V screws, three samples were outside the standard values. One CP-Ti screw sample and one plate sample also presented an oxygen analysis value above the standard. The results indicated that the physical properties and chemical compositions of the plates and screws did not correspond with the need to remove these devices or the time of retention.

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.

Key Participants Of The Tumor Microenvironment Of The Prostate: An Approach Of The Structural Dynamic Of Cellular Elements And Extracellular Matrix Components During Epithelial-stromal Transition.

Cancer is a multistep process that begins with the transformation of normal epithelial cells and continues with tumor growth, stromal invasion and metastasis. The remodeling of the peritumoral environment is decisive for the onset of tumor invasiveness. This event is dependent on epithelial-stromal interactions, degradation of extracellular matrix components and reorganization of fibrillar components. Our research group has studied in a new proposed rodent model the participation of cellular and molecular components in the prostate microenvironment that contributes to cancer progression. Our group adopted the gerbil Meriones unguiculatus as an alternative experimental model for prostate cancer study. This model has presented significant responses to hormonal treatments and to development of spontaneous and induced neoplasias. The data obtained indicate reorganization of type I collagen fibers and reticular fibers, synthesis of new components such as tenascin and proteoglycans, degradation of basement membrane components and elastic fibers and increased expression of metalloproteinases. Fibroblasts that border the region, apparently participate in the stromal reaction. The roles of each of these events, as well as some signaling molecules, participants of neoplastic progression and factors that promote genetic reprogramming during epithelial-stromal transition are also discussed.

O estado da arte da cromatografia associada à espectrometria de massas acoplada à espectrometria de massas na análise de compostos tóxicos em alimentos

Chromatography combined with several different detection systems is one of the more used and better performing analytical tools. Chromatography with tandem mass spectrometric detection gives highly selective and sensitive analyses and permits obtaining structural information about the analites and about their molar masses. Due to these characteristics, this analytical technique is very efficient when used to detect substances at trace levels in complex matrices. In this paper we review instrumental and technical aspects of chromatography-tandem mass spectrometry and the state of the art of the technique as it is applied to analysis of toxic substances in food.

Ontogenia e estrutura do pericarpo de Prestonia riedelii (Müll. Arg.) Markgr. (Apocynaceae)

The aim of this work was to describe the morphology and ontogeny of P. riedelii fruits to aid in taxonomic, ecological and phylogenetic studies in Apocynaceae. Fruits were fixed in FAA, embedded in plastic resin, sectioned at 10 ìm and stained with toluidine blue, for structural analysis. The fruit of P. riedelii is a follicarium, with two follicular fruitlets. The epicarp is one-cell-layered, with trichomes and thick cuticle. The mesocarp, originating from fundamental ovary tissue, is parenchymatous with laticifers, non-lignified fibers and vascular bundles. The endocarp sensu lato is two-celllayered of crossed sclereids, originating from the inner ovary epidermis and from a single layer of parenchyma cells of fundamental ovary tissue. Follicle dehiscence is lateral and the dehiscence process involves anatomical characteristics such as a dehiscence zone with thin-walled cells, non-lignified fibers in the mesocarp and crossed sclereids in the endocarp.