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1.
Plant Biol (Stuttg) ; 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38837312

ABSTRACT

Rocky outcrop environments at high altitudes have nutrient-poor soil, where species are exposed to water scarcity and high solar radiation. Baccharis platypoda DC. occurs in such an environment and has a rigid and transparent secretion that covers the entire inflorescence. We analysed and compared the secretory structures and their chemical composition in female and male inflorescences of B. platypoda, a dioecious species, to explore chemodiversity within this species and assess potential differences between individuals. Our investigation also aims to understand the occurrence of these substances in the genus Baccharis L. Chemical compounds and secretory structures were similar in female and male inflorescences. There are glandular trichomes on the epidermis of the abaxial surface of bracts, and secretory ducts in the axis of the inflorescence, as well as in sepals, petals, and bracts. Histochemical tests were positive for phenolic compounds, flavonoids, proteins, pectin, and lipids, but not for mucilage. Flavonoid content varied between 6.24% and 9.81%, being higher in female inflorescences. Chromatography revealed the presence of several phenolic compounds, some terpenes, and other less frequent classes in both female and male inflorescences. We highlight that trichomes found on these surfaces produce abundant phenolic compounds. These act as natural defence agents, absorbing UV radiation and minimizing oxidative stress to plant cells. The chemical composition of the secretion covering the inflorescences may reflect adaptation and survival mechanisms of these organisms under extreme sun exposure.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 297: 122746, 2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37086536

ABSTRACT

Crystals of dipeptide α-L-aspartyl-L-alanine (α-Asp-Ala), C7H12N2O5, were studied under high-temperature conditions through vibrational spectroscopy (IR and Raman) and thermal analysis (Differential Scanning Calorimetry - DSC). From the analysis of the results, it is possible to conclude that: (i) the studied material undergoes a reversible order-disorder phase transition at 373 K on heating, where several changes were observed in the vibrational spectra, especially with vibrational modes of the units that participate directly of the hydrogen bonds; (ii) the phase transition undergone by the α-Asp-Ala crystal (about 373 K) involves changes in hydrogen bonds, possibly the rupture of at least one of them, and change in the conformation of the molecules in the unit cell.

3.
Sci Med Footb ; 6(4): 494-502, 2022 11.
Article in English | MEDLINE | ID: mdl-36412173

ABSTRACT

PURPOSE: This study aimed to compare the attention performance, by playing position, in elite Brazilian football players. METHODS: A total of 66 professional players competing in the first division of the Brazilian Championship were evaluated. They were grouped according to their playing positions into 7 goalkeepers, 8 defenders, 15 fullbacks, 8 defensive midfielders, 13 attacking midfielders, and 15 forwards. The attention was evaluated using the QuotientTM ADHD System equipment. The group performances were compared using the Kruskal-Wallis Test and the post-hoc analysis using the Mann-Whitney Test. RESULTS: Fullbacks showed less attentive behavior than defenders (U = 9.000, p = 0.001), defensive midfielders (U = 12.500, p = 0.002), offensive midfielders (U = 48.000, p = 0.007) and forwards (U = 27.000, p = 0.001). Fullbacks also had impulsive behavior longer than defenders (U = 10.500, p = 0.001) and defensive midfielders (U = 12.000, p = 0.002), as well as offensive midfielders had impulsive behavior longer than defenders (U = 16.0000, p = 0.004) and defensive midfielders (U = 19.500, p = 0.009). CONCLUSION: Players of defensive positions, as defenders and defensive midfielders, were more attentive and less impulsive than players of hybrid positions, responsible for both defensive and offensive actions, such as fullbacks and attacking midfielders. The present finding indicates that the defenders were the players who maintained the attention level for more time, while the fullbacks maintained for less time. Players in offensive playing positions (fullbacks and attacking midfielders) maintained their impulsive behavior for longer when compared to defensive positions (defenders and defensive midfielders).


Subject(s)
Athletic Performance , Football , Soccer , Impulsive Behavior , Attention
4.
Hematol., Transfus. Cell Ther. (Impr.) ; 43(4): 468-475, Oct.-Dec. 2021. tab, graf
Article in English | LILACS | ID: biblio-1350824

ABSTRACT

ABSTRACT Introduction: Although the efficacy of hydroxyurea (HU) in inhibiting erythrocyte sickling has been well demonstrated, the action of this drug on human neutrophils and the mechanism by which it improves the manifestations of the disease have not been studied thoroughly. We aimed to investigate the cell viability, along with inflammatory and oxidative markers in the neutrophils of sickle cell anemia (SCA) patients and the effects of HU therapy on these cells, by evaluating the dose-responsiveness. Methods: In the present study, 101 patients (45 men and 56 women, aged 18-69 years) with SCA were divided into groups according to the use or not of HU: the SS group (without HU treatment, n = 47) and the SSHU group (under HU treatment, n = 54). The SSHU group was further stratified into subgroups according to the daily dose of the drug that patients already used: SSHU - 0.5 g (n = 19); SSHU - 1 g (n = 26) and SSHU - 1.5-2 g (n = 9). A control group (AA) comprised 50 healthy individuals. Neutrophils isolated from whole blood were analyzed using Trypan Blue, monoiodotyrosine (MTT) and lactate dehydrogenase (LDH) toxicity assays. Myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities and concentrations of interleukin 10 (IL-10), tumor necrosis factor alpha (TNF-α) and malonaldehyde (MDA) were also measured. Results: Neutrophils from SCA patients showed membrane fragility and a significant decrease in cell viability when analyzed by Trypan Blue (p < 0.05), MTT (p < 0.001) and LDH (p = 0.011), compared to the AA group. Levels of inflammatory (MPO, TNF-α, and IL-10) and oxidative markers (SOD, GSH-Px, and MDA) were also altered (p < 0.05) in these cells, showing a significant difference in the SSHU-1g and SSHU - 1.5-2 g groups, compared to the SS group. Treatment with HU reverted the levels of all markers to concentrations similar to those in healthy individuals in a positive dose-effect relationship. Conclusion: The HU did not generate a cytotoxic effect on neutrophils in SCA patients, but it modulated their oxidative and inflammatory mechanisms, promoting cytoprotection with a positive dose-effect.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Hydroxyurea , Anemia, Sickle Cell , Tumor Necrosis Factor-alpha , Oxidative Stress , Cytotoxicity, Immunologic , Dosage , Inflammation , Malondialdehyde , Neutrophils
5.
Hematol Transfus Cell Ther ; 43(4): 468-475, 2021.
Article in English | MEDLINE | ID: mdl-33051133

ABSTRACT

INTRODUCTION: Although the efficacy of hydroxyurea (HU) in inhibiting erythrocyte sickling has been well demonstrated, the action of this drug on human neutrophils and the mechanism by which it improves the manifestations of the disease have not been studied thoroughly. We aimed to investigate the cell viability, along with inflammatory and oxidative markers in the neutrophils of sickle cell anemia (SCA) patients and the effects of HU therapy on these cells, by evaluating the dose-responsiveness. METHODS: In the present study, 101 patients (45 men and 56 women, aged 18-69 years) with SCA were divided into groups according to the use or not of HU: the SS group (without HU treatment, n = 47) and the SSHU group (under HU treatment, n = 54). The SSHU group was further stratified into subgroups according to the daily dose of the drug that patients already used: SSHU - 0.5 g (n = 19); SSHU - 1 g (n = 26) and SSHU - 1.5-2 g (n = 9). A control group (AA) comprised 50 healthy individuals. Neutrophils isolated from whole blood were analyzed using Trypan Blue, monoiodotyrosine (MTT) and lactate dehydrogenase (LDH) toxicity assays. Myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities and concentrations of interleukin 10 (IL-10), tumor necrosis factor alpha (TNF-α) and malonaldehyde (MDA) were also measured. RESULTS: Neutrophils from SCA patients showed membrane fragility and a significant decrease in cell viability when analyzed by Trypan Blue (p < 0.05), MTT (p < 0.001) and LDH (p = 0.011), compared to the AA group. Levels of inflammatory (MPO, TNF-α, and IL-10) and oxidative markers (SOD, GSH-Px, and MDA) were also altered (p < 0.05) in these cells, showing a significant difference in the SSHU-1g and SSHU - 1.5-2 g groups, compared to the SS group. Treatment with HU reverted the levels of all markers to concentrations similar to those in healthy individuals in a positive dose-effect relationship. CONCLUSION: The HU did not generate a cytotoxic effect on neutrophils in SCA patients, but it modulated their oxidative and inflammatory mechanisms, promoting cytoprotection with a positive dose-effect.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 241: 118643, 2020 Nov 05.
Article in English | MEDLINE | ID: mdl-32682278

ABSTRACT

Raman spectra of Fe-doped L-asparagine monohydrate (LAM:Fe) crystal were studied under several temperatures varying from 17 to 490 K. The effect of Fe (III) ion on the stability of the crystal in changing temperature through the vibrational spectra was discussed. The behavior of inter and intra-molecular vibration modes has indicated two phase transitions and an amorphous transformation. These effects were also clarified by X-ray powder diffraction measurements which corroborate very well the Raman data. In addition, we have determinated the lattice parameters of all phases and verified that under low temperature conditions the crystal undergoes a conformational transition whereas under high temperatures its structure transforms from the orthorhombic (P212121-space group) to the monoclinic (P21-space group) symmetry and, after this process, it goes to an amorphous phase due to the start of the decomposition. Finally, differential scanning calorimetry analysis was utilized as complementary technique to investigate the structural stability of LAM:Fe and results are in a good agreement with the Raman and the X-ray diffraction data.

7.
Anaerobe ; 59: 145-153, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31254652

ABSTRACT

Glycerol, the main residue of biodiesel production, can be used to produce organic acids and energy through anaerobic digestion. This study aimed to assess microbial structure, diversity, productivity, and stability and the influence of these parameters on the performance of an anaerobic reactor. The experimental setup consisted of an upflow anaerobic sludge blanket (UASB) reactor fed residual glycerol and nutrients. The organic loading rate (OLR) was gradually increased through five stages, and sludge samples were collected at each, followed by DNA extraction and PCR denaturing gradient gel electrophoresis (PCR-DGGE). The resulting bands were excised, amplified, and purified. The results showed increased bacterial diversity and richness from the inoculum (Rr 38.72 and H 2.32) and along stages I and II, reaching the highest populational parameters (Rr 194.06 and H 3.32). The following stages promote decreases in richness and diversity, achieving the lowest populational parameters on this study (Rr 11.53 and H 2.04). Biogas production increased along with functional organization due to the specialization of the bacterial community and a decrease in the methanogenic population, both promoted by the increase in OLR.


Subject(s)
Archaea/classification , Archaea/isolation & purification , Bacteria, Anaerobic/classification , Bacteria, Anaerobic/isolation & purification , Bioreactors/microbiology , Biota , Glycerol/metabolism , Anaerobiosis , Carboxylic Acids/metabolism
8.
Arq. bras. med. vet. zootec. (Online) ; 71(2): 369-373, mar.-abr. 2019. ilus
Article in English | VETINDEX | ID: vti-23523

ABSTRACT

Equine piroplasmosis is a tick-borne disease caused by the protozoan parasites Babesia caballi and Theileria equi. We report a case of abortion in association with transplacental Theileria equi infection in a mare from the State of Espírito Santo, southeast Brazil. An apparently healthy mare aborted at the tenth month of gestation. At necropsy, the subcutaneous tissue, skeletal muscles, and visible mucosae of the aborted fetus were pale, and there was moderate hydrothorax and marked splenomegaly. Microscopic findings included splenic lymphoid hyperplasia and nephrosis. Merozoite-infected erythrocytes were found within blood vessels of all organs examined and were most numerous in the brain. DNA extracted from the spleen, liver, kidney, and thymus was used as a template for PCR. Generic primers were employed for the detection of piroplasm 18S ribosomal gene. All samples were positive for piroplasm DNA by PCR. Amplicons were purified and then sequenced. Sequencing analysis of these amplicons revealed 98% identity to T. equi sequences. Based on our findings, we suggest that abortion in this case resulted from transplacental Theileria infection.(AU)


A piroplasmose equina é transmitida por carrapatos, sendo causada pelos protozoários Babesia caballi e Theileria equi. O objetivo deste trabalho foi relatar um caso de aborto equino associado à piroplasmose fetal. Uma égua gestante, aparentemente saudável, abortou no 10º mês de gestação. Na necropsia do feto, foi observada palidez de subcutâneo, da musculatura esquelética e das mucosas visíveis, moderado hidrotórax e acentuada esplenomegalia. Histologicamente, havia hiperplasia linfoide esplênica e nefrose. Muitos merozoítos foram observados em eritrócitos nos vasos sanguíneos de todos os órgãos examinados, com maior intensidade no encéfalo. Amostras de DNA do baço, fígado, rim e timo foram utilizadas para PCR com primers genéricos para detecção de sequências do gene 18S ribossomal de piroplasmas, com resultado positivo para todas as amostras. Em seguida, os amplicons das amostras de baço foram purificados, sequenciados e, após análise, mostraram 98% de identidade com a sequência de T. equi. Portanto, as alterações microscópicas, os resultados de PCR e sequenciamento confirmam aborto associado à T. equi por transmissão transplacentária.(AU)


Subject(s)
Animals , Female , Pregnancy , Theileriasis , Babesiosis , Abortion, Veterinary/parasitology , Fetal Death/etiology , Horse Diseases , Horses
9.
Arq. bras. med. vet. zootec. (Online) ; 71(2): 369-373, mar.-abr. 2019. ilus
Article in English | VETINDEX, LILACS | ID: biblio-1011261

ABSTRACT

Equine piroplasmosis is a tick-borne disease caused by the protozoan parasites Babesia caballi and Theileria equi. We report a case of abortion in association with transplacental Theileria equi infection in a mare from the State of Espírito Santo, southeast Brazil. An apparently healthy mare aborted at the tenth month of gestation. At necropsy, the subcutaneous tissue, skeletal muscles, and visible mucosae of the aborted fetus were pale, and there was moderate hydrothorax and marked splenomegaly. Microscopic findings included splenic lymphoid hyperplasia and nephrosis. Merozoite-infected erythrocytes were found within blood vessels of all organs examined and were most numerous in the brain. DNA extracted from the spleen, liver, kidney, and thymus was used as a template for PCR. Generic primers were employed for the detection of piroplasm 18S ribosomal gene. All samples were positive for piroplasm DNA by PCR. Amplicons were purified and then sequenced. Sequencing analysis of these amplicons revealed 98% identity to T. equi sequences. Based on our findings, we suggest that abortion in this case resulted from transplacental Theileria infection.(AU)


A piroplasmose equina é transmitida por carrapatos, sendo causada pelos protozoários Babesia caballi e Theileria equi. O objetivo deste trabalho foi relatar um caso de aborto equino associado à piroplasmose fetal. Uma égua gestante, aparentemente saudável, abortou no 10º mês de gestação. Na necropsia do feto, foi observada palidez de subcutâneo, da musculatura esquelética e das mucosas visíveis, moderado hidrotórax e acentuada esplenomegalia. Histologicamente, havia hiperplasia linfoide esplênica e nefrose. Muitos merozoítos foram observados em eritrócitos nos vasos sanguíneos de todos os órgãos examinados, com maior intensidade no encéfalo. Amostras de DNA do baço, fígado, rim e timo foram utilizadas para PCR com primers genéricos para detecção de sequências do gene 18S ribossomal de piroplasmas, com resultado positivo para todas as amostras. Em seguida, os amplicons das amostras de baço foram purificados, sequenciados e, após análise, mostraram 98% de identidade com a sequência de T. equi. Portanto, as alterações microscópicas, os resultados de PCR e sequenciamento confirmam aborto associado à T. equi por transmissão transplacentária.(AU)


Subject(s)
Animals , Female , Pregnancy , Theileriasis , Babesiosis , Abortion, Veterinary/parasitology , Fetal Death/etiology , Horse Diseases , Horses
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 208: 97-108, 2019 Feb 05.
Article in English | MEDLINE | ID: mdl-30296674

ABSTRACT

In this study, the vibrational frequencies of myristic acid (CH3(CH2)12COOH) were obtained using density functional theory calculations, and the results were compared with experimental Raman and infrared data. Additionally, Raman spectra of crystalline myristic acid were recorded in the 300-20 K range. Raman spectroscopy gives important insights into the effect of low temperatures on its monoclinic phase. X-ray diffraction was performed from 298 to 133 K to provide additional information about the cryogenic behavior of the crystals. These undergo a phase transformation, which was confirmed by differential scanning calorimetry through an enthalpy anomaly observed at low temperatures. Raman spectra and X-ray diffraction refinement of the cell parameters in combination with differential scanning calorimetry at low temperatures revealed slight modifications, confirming a conformational change in the myristic acid molecules involving rearrangement of dimers within the unit cell.

11.
Arq. bras. med. vet. zootec. (Online) ; 70(5): 1547-1556, set.-out. 2018. tab, graf
Article in English | VETINDEX | ID: vti-18462

ABSTRACT

The study aimed to evaluate the action of aqueous extract of noni in an extender for sheep semen freezing. Treatments differed in inclusion of aqueous extract of noni in the extender: T1 ˗ no addition; T2 ˗ 24µg/mL; T3 ˗ 72µg/mL; and T4 ˗ 120µg/mL. Ejaculates were collected, diluted in the four treatments, and frozen. After thawing, the semen was subjected to a thermoresistance test and evaluated for subjective motility, vigor, membrane integrity assessment by hypo-osmotic swelling test, live-dead assay, computer-assisted sperm analysis and the status of sperm capacitation and acrosome reaction. Data were subjected to ANOVA, and then to Student Newman Keuls's test at 5% significance level. In the thermoresistance test after two hours of incubation, motility in T4 (120µg/mL) was lower than in the other treatments, with no differences in the HoS test in either diluted semen or in the semen evaluated immediately post-thawing, while for the other times, treatments showed similar responses. Regarding the motility parameters, a difference was observed for progressive motility, curvilinear velocity, average path velocity, and amplitude of lateral head displacement. As to the sperm capacitation status, a difference was observed between treatments for the sperm capacitated with intact acrosome.(AU)


Este estudo teve como objetivo avaliar a ação do extrato aquoso de noni em diluente para congelação de sêmen de carneiro. Os tratamentos diferiram quanto à inclusão de extrato aquoso de noni ao meio diluidor em: T1˗ sem adição de extrato; T2˗ 24µg/mL ; T3- 72µg/mL e 120µg/mL. Por meio de vagina artificial, 16 ejaculados foram coletados, diluídos entre os quatro tratamentos e congelados. Após o descongelamento, o sêmen foi submetido ao teste de termorresistência e avaliado quanto à motilidade subjetiva, ao vigor espermático, à integridade de membrana pelo teste hiposmótico, bem como ao teste supravital, à análise de sêmen assistida por computador (CASA) e ao status de capacitação espermática e de reação acrossomal. Os dados foram submetidos a uma análise de variância, seguida pelo teste de Student-Newman-Keuls com 5% de significância. No teste de termorresistência, após duas horas de incubação, a motilidade do T4 (120µg/mL) apresentou-se inferior aos demais tratamentos. Não houve diferença significativa no teste HOS tanto para o sêmen diluído quanto para o sêmen avaliado imediatamente pós-descongelação; para as demais horas, os tratamentos apresentaram comportamento semelhante. Para os parâmetros de cinética, foi observada diferença estatística para motilidade progressiva, velocidade curvilinear, velocidade do percurso médio e amplitude de deslocamento lateral da cabeça. Quanto ao estado de capacitação espermática, observou-se diferença entre os tratamentos para espermatozoide capacitado com acrossomo intacto.(AU)


Subject(s)
Animals , Lipid Peroxides/chemistry , Semen Preservation/veterinary , Sheep/embryology , Cell Membrane
12.
Arq. bras. med. vet. zootec. (Online) ; 70(5): 1547-1556, set.-out. 2018. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-947287

ABSTRACT

The study aimed to evaluate the action of aqueous extract of noni in an extender for sheep semen freezing. Treatments differed in inclusion of aqueous extract of noni in the extender: T1 ˗ no addition; T2 ˗ 24µg/mL; T3 ˗ 72µg/mL; and T4 ˗ 120µg/mL. Ejaculates were collected, diluted in the four treatments, and frozen. After thawing, the semen was subjected to a thermoresistance test and evaluated for subjective motility, vigor, membrane integrity assessment by hypo-osmotic swelling test, live-dead assay, computer-assisted sperm analysis and the status of sperm capacitation and acrosome reaction. Data were subjected to ANOVA, and then to Student Newman Keuls's test at 5% significance level. In the thermoresistance test after two hours of incubation, motility in T4 (120µg/mL) was lower than in the other treatments, with no differences in the HoS test in either diluted semen or in the semen evaluated immediately post-thawing, while for the other times, treatments showed similar responses. Regarding the motility parameters, a difference was observed for progressive motility, curvilinear velocity, average path velocity, and amplitude of lateral head displacement. As to the sperm capacitation status, a difference was observed between treatments for the sperm capacitated with intact acrosome.(AU)


Este estudo teve como objetivo avaliar a ação do extrato aquoso de noni em diluente para congelação de sêmen de carneiro. Os tratamentos diferiram quanto à inclusão de extrato aquoso de noni ao meio diluidor em: T1˗ sem adição de extrato; T2˗ 24µg/mL ; T3- 72µg/mL e 120µg/mL. Por meio de vagina artificial, 16 ejaculados foram coletados, diluídos entre os quatro tratamentos e congelados. Após o descongelamento, o sêmen foi submetido ao teste de termorresistência e avaliado quanto à motilidade subjetiva, ao vigor espermático, à integridade de membrana pelo teste hiposmótico, bem como ao teste supravital, à análise de sêmen assistida por computador (CASA) e ao status de capacitação espermática e de reação acrossomal. Os dados foram submetidos a uma análise de variância, seguida pelo teste de Student-Newman-Keuls com 5% de significância. No teste de termorresistência, após duas horas de incubação, a motilidade do T4 (120µg/mL) apresentou-se inferior aos demais tratamentos. Não houve diferença significativa no teste HOS tanto para o sêmen diluído quanto para o sêmen avaliado imediatamente pós-descongelação; para as demais horas, os tratamentos apresentaram comportamento semelhante. Para os parâmetros de cinética, foi observada diferença estatística para motilidade progressiva, velocidade curvilinear, velocidade do percurso médio e amplitude de deslocamento lateral da cabeça. Quanto ao estado de capacitação espermática, observou-se diferença entre os tratamentos para espermatozoide capacitado com acrossomo intacto.(AU)


Subject(s)
Animals , Lipid Peroxides/chemistry , Semen Preservation/veterinary , Sheep/embryology , Cell Membrane
13.
J Laryngol Otol ; 131(7): 627-630, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28462728

ABSTRACT

BACKGROUND: Peritonsillar abscess is the most common deep infection of the head and neck in young adults. It is considered a purulent complication of acute tonsillitis, but other mechanisms have been proposed. There is no consensus as to whether seasonality affects peritonsillar abscess incidence. METHODS: This observational, descriptive, retrospective study explored the epidemiology of peritonsillar abscess and its relationship with seasonality. The cases were selected from the emergency otolaryngology service of a tertiary hospital. RESULTS: The sample comprised 528 patients (42.61 per cent males, mean age = 26.63 years). A moderate positive correlation was found between peritonsillar abscess incidence and monthly average temperature. No associations were found with insolation, precipitation or humidity. CONCLUSION: In this sample, peritonsillar abscess was more likely to occur in warmer months. The findings corroborate the theory that peritonsillar abscess is not a direct complication of acute tonsillitis and may improve understanding of peritonsillar abscess aetiology.


Subject(s)
Climate , Peritonsillar Abscess/epidemiology , Peritonsillar Abscess/etiology , Adolescent , Adult , Age Factors , Aged , Brazil , Child , Cross-Sectional Studies , Female , Humans , Humidity , Male , Middle Aged , Retrospective Studies , Statistics as Topic , Temperature , Tropical Climate , Young Adult
14.
Article in English | MEDLINE | ID: mdl-25909902

ABSTRACT

This paper reports the temperature-dependent measurements in the C form of stearic acid. Raman scattering, X-ray diffraction, and differential scanning calorimetry measurements were performed at low temperatures. The polarized Raman spectra were measured for temperatures ranging from 8 to 300 K over the spectral range of 30-3000 cm(-1). The spectral changes observed in both the lattice vibrational modes and the internal vibrational modes regions of the Raman spectrum, allowed to identify a phase transition undergone by the stearic acid crystal occurring between 210 and 170 K and a change in the structure continues to be observed down to 8 K. The anharmonicity of some vibrational modes and the possible space groups presented by the crystal at low temperatures were also discussed. Low-temperature X-ray diffraction measurements were performed from 290 to 80 K and the results showed slight changes in the lattice parameters at ∼200 K. Furthermore, the evidence of the phase transformation was provided by the differential scanning calorimetry measurements, which identified an enthalpic anomaly at about 160 K.


Subject(s)
Phase Transition , Stearic Acids/chemistry , Cold Temperature , Models, Molecular , Powder Diffraction , Spectrum Analysis, Raman , X-Ray Diffraction
15.
Article in English | MEDLINE | ID: mdl-25897718

ABSTRACT

A single-crystal of peptide L-alanyl-L-alanine (C6H12N2O3) was studied by Raman spectroscopy at low-temperature, and a tentative assignment of the normal modes was given. Evidence of a second order structural phase transition was found through Raman spectroscopy between the temperatures of 80K and 60K. Group theory considerations suggest that the transition leads the sample from the tetragonal to a monoclinic structure. Additionally, our study suggests that the mechanism for the structural phase transition is governed by the occupation of non-equivalent C1 local symmetry sites by the CH3 molecular groups. Analysis based on group theory suggests L-alanyl-L-alanine presents C2 symmetry at low temperatures.


Subject(s)
Dipeptides/chemistry , Spectrum Analysis, Raman/methods , Cold Temperature , Crystallization , Models, Molecular , Phase Transition
16.
Arq. bras. med. vet. zootec ; 66(4): 1105-1111, 08/2014. graf
Article in Portuguese | VETINDEX | ID: vti-11085

ABSTRACT

O Tamandua tetradactyla é uma espécie da ordem Xenarthra que apresenta coloração amarelada na cabeça, nos membros e na parte anterior do dorso, sendo o restante do corpo negro, formando uma espécie de colete, por isso também é chamado de "tamanduá-de-colete". Objetivou-se descrever a morfologia, a topografia e a irrigação cardíaca do Tamandua tetradactyla. Foram utilizados quatro espécimes jovens, provenientes da área de Mina Bauxita - Paragominas, Pará, que foram doados à Universidade Federal Rural da Amazônia - UFRA, após morte por atropelamento. O sistema arterial foi preenchido com látex contrastado, e os animais foram fixados em uma solução de formaldeído a 10%. A cavidade torácica foi acessada e permitiu a análise topográfica do coração, com posterior mensuração, descrição morfológica e vascular. O coração estava localizado entre o terceiro e o quinto espaço intercostal, apresentando duas artérias coronárias, direita e esquerda, que se originaram do seio aórtico. O tipo de irrigação para esta espécie variou entre a do tipo equilibrada e a direita. Nos sulcos coronários, localizavam-se os ramos circunflexos das artérias coronárias, originando os ramos interventriculares paraconal e subsinuoso. Além das quatro câmaras cardíacas, observaram-se também as valvas tricúspide e bicúspide, cordas tendíneas, trabéculas carnosas e trabéculas septo marginal, músculos papilares nas câmaras ventriculares e músculos pectiniformes nas câmaras atriais.(AU)


The Tamandua tetradactyla and a specie of the Xenarthra order that presents yellowish color in the head, limbs and anterior part of the dorsum and the rest of the black body, forming a sort of vest, so it is also called "collared anteater". This study aimed to describe the morphology, topography and cardiac irrigation of the Tamandua tetradactyla. Four young specimens were used, from the bauxite mine area - Paragominas, Pará, which were donated to the Federal Rural University of Amazon - UFRA, after death due to running over. The arterial system was filled with contrasted latex and the animals were fixed in a 10% formaldehyde solution. The thoracic cavity was accessed by allowing the topographic analysis of the heart, with subsequent measurement, morphological and vascular description. The heart was located between the 3rd and 5th intercostal space, showing two coronary arteries, dextra and sinistra, that originated from the Sinus aortae. The type of irrigation for this species varied between the balanced and the right. In the coronary sulcus there were branches of circumflex coronary arteries, originating the Ramus interventricularis subsinuosus and Ramus interventricularis paraconalis. In addition to the four cardiac chambers we observed the tricuspid and bicuspid valves, chordae tendineae, trabeculaes carneae and trabeculaes septomarginales, the Musculus papillaris in ventricular chambers and Musculus pectiniform in atrial chambers.(AU)


Subject(s)
Animals , Xenarthra/anatomy & histology , Heart/anatomy & histology , Coronary Vessels/anatomy & histology , Myocardium , Thorax
17.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);66(4): 1105-1111, 08/2014. graf
Article in Portuguese | LILACS | ID: lil-722586

ABSTRACT

O Tamandua tetradactyla é uma espécie da ordem Xenarthra que apresenta coloração amarelada na cabeça, nos membros e na parte anterior do dorso, sendo o restante do corpo negro, formando uma espécie de colete, por isso também é chamado de "tamanduá-de-colete". Objetivou-se descrever a morfologia, a topografia e a irrigação cardíaca do Tamandua tetradactyla. Foram utilizados quatro espécimes jovens, provenientes da área de Mina Bauxita - Paragominas, Pará, que foram doados à Universidade Federal Rural da Amazônia - UFRA, após morte por atropelamento. O sistema arterial foi preenchido com látex contrastado, e os animais foram fixados em uma solução de formaldeído a 10%. A cavidade torácica foi acessada e permitiu a análise topográfica do coração, com posterior mensuração, descrição morfológica e vascular. O coração estava localizado entre o terceiro e o quinto espaço intercostal, apresentando duas artérias coronárias, direita e esquerda, que se originaram do seio aórtico. O tipo de irrigação para esta espécie variou entre a do tipo equilibrada e a direita. Nos sulcos coronários, localizavam-se os ramos circunflexos das artérias coronárias, originando os ramos interventriculares paraconal e subsinuoso. Além das quatro câmaras cardíacas, observaram-se também as valvas tricúspide e bicúspide, cordas tendíneas, trabéculas carnosas e trabéculas septo marginal, músculos papilares nas câmaras ventriculares e músculos pectiniformes nas câmaras atriais...


The Tamandua tetradactyla and a specie of the Xenarthra order that presents yellowish color in the head, limbs and anterior part of the dorsum and the rest of the black body, forming a sort of vest, so it is also called "collared anteater". This study aimed to describe the morphology, topography and cardiac irrigation of the Tamandua tetradactyla. Four young specimens were used, from the bauxite mine area - Paragominas, Pará, which were donated to the Federal Rural University of Amazon - UFRA, after death due to running over. The arterial system was filled with contrasted latex and the animals were fixed in a 10% formaldehyde solution. The thoracic cavity was accessed by allowing the topographic analysis of the heart, with subsequent measurement, morphological and vascular description. The heart was located between the 3rd and 5th intercostal space, showing two coronary arteries, dextra and sinistra, that originated from the Sinus aortae. The type of irrigation for this species varied between the balanced and the right. In the coronary sulcus there were branches of circumflex coronary arteries, originating the Ramus interventricularis subsinuosus and Ramus interventricularis paraconalis. In addition to the four cardiac chambers we observed the tricuspid and bicuspid valves, chordae tendineae, trabeculaes carneae and trabeculaes septomarginales, the Musculus papillaris in ventricular chambers and Musculus pectiniform in atrial chambers...


Subject(s)
Animals , Heart/anatomy & histology , Coronary Vessels/anatomy & histology , Xenarthra/anatomy & histology , Myocardium , Thorax
18.
Article in English | MEDLINE | ID: mdl-21097117

ABSTRACT

The objective of this study was to evaluate the clinical potential of the Forced Oscillation Technique (FOT) in the detection of the early alterations in respiratory mechanics of Rheumatoid Arthritis (RA) patients. A total of 36 individuals were analyzed, 18 healthy and 18 with RA. The clinical usefulness of the parameters was evaluated investigating sensibility (Se), specificity (Sp) and the area under the receiver operating characteristic curve (AUC). In the RA group, all the 3 studied parameters obtained high accuracy for clinical use (AUC>0.9), while in spirometric parameters, no parameter obtained appropriate accuracy for clinical use (AUC < 0.7). In conclusion, the parameters obtained by FOT presented adequate Se and Sp, indicating that this technique can be helpful in the evaluation of the early respiratory mechanical alterations in patients with RA.


Subject(s)
Arthritis, Rheumatoid/diagnosis , Arthritis, Rheumatoid/physiopathology , Respiratory Function Tests/methods , Respiratory Mechanics/physiology , Airway Resistance , Area Under Curve , Early Diagnosis , Female , Humans , Male , Middle Aged , ROC Curve , Respiratory Function Tests/instrumentation , Sensitivity and Specificity , Spirometry
19.
Int J Clin Pract ; 60(10): 1172-7, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16942589

ABSTRACT

Brazilian patients with benign prostatic hyperplasia were randomised in a 12-week, double-blind, double-dummy study to receive doxazosin gastrointestinal therapeutic system (GITS) 4 mg q.i.d. (n = 82) or tamsulosin 0.4 q.i.d. (n = 83). Primary endpoints were the absolute and percentage change from baseline in symptoms measured by International Prostate Symptom Score (IPSS). Secondary endpoints included IPSS, quality-of-life (QOL) question from the IPSS, and questions 6 and 7 of the Sexual Function Abbreviated Questionnaire (SFAQ) at weeks 4 and 12. Doxazosin GITS and tamsulosin improved IPSS with no significant differences between groups at week 12. During weeks 4-8, tamsulosin-treated patients demonstrated a slower improvement (p < 0.001) in IPSS than doxazosin GITS-treated patients. The proportion of satisfied patients was observed earlier with doxazosin GITS (p = 0.006) vs. tamsulosin. At week 12, the proportion of patients with little or no difficulty at ejaculation (Q6 of SFAQ) was higher in the doxazosin GITS group (p = 0.019). Both treatments were well tolerated.


Subject(s)
Adrenergic alpha-Antagonists/therapeutic use , Doxazosin/therapeutic use , Prostatic Hyperplasia/drug therapy , Sulfonamides/therapeutic use , Aged , Delayed-Action Preparations , Double-Blind Method , Drug Therapy, Combination , Humans , Male , Middle Aged , Patient Satisfaction , Quality of Life , Tamsulosin , Treatment Outcome
20.
Toxicol In Vitro ; 20(8): 1478-80, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16797914

ABSTRACT

ACLMT is a myotoxic Lys49 phospholipase A(2) isolated from the venom of the snake Agkistrodon contortrix laticinctus. We have previously shown that ACLMT increases baseline water transport and partially inhibits vasopressin-stimulated water transport across toad bladders due to an increase in cytosolic calcium. However, these evidences provide insufficient insight into the mechanisms involved in the effects of ACLMT on membrane permeability. In an attempt to better understand such mechanisms, the current study aimed to investigate whether the Na(+)/K(+)-ATPase activity of isolated toad bladders can be affected by the ACLMT and the synthetic peptide from its C-terminal region. The toxin significantly decreased the Na(+)/K(+)-ATPase, while the peptide did not alter it. These findings suggest that the effects of ACLMT on membrane permeability may be due to the inhibition of the Na(+)/K(+)-ATPase activity, and that the C-terminal region may not play a relevant role in this effect. This study contributes toward a better understanding of the mechanisms involved in the toxicity of the snake venom Lys49 PLA(2) myotoxins on biological tissues.


Subject(s)
Agkistrodon/physiology , Crotalid Venoms/enzymology , Crotalid Venoms/toxicity , Phospholipases A/toxicity , Sodium-Potassium-Exchanging ATPase/metabolism , Urinary Bladder/enzymology , Animals , Bufo marinus , Cell Membrane Permeability/drug effects , Urinary Bladder/drug effects
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