Antifungal activity of 2-chloro-N-phenylacetamide: a new molecule with fungicidal and antibiofilm activity against fluconazole-resistant Candida spp / Atividade antifúngica de 2-cloro-N-fenilacetamida: uma nova molécula com atividade fungicida e anti-biofilme contra Candida spp. resistentes a fluconazol

In the current context of emerging drug-resistant fungal pathogens such as Candida albicans and Candida parapsilosis, discovery of new antifungal agents is an urgent matter. This research aimed to evaluate the antifungal potential of 2-chloro-N-phenylacetamide against fluconazole-resistant clinical strains of C. albicans and C. parapsilosis. The antifungal activity of 2-chloro-N-phenylacetamide was evaluated in vitro by the determination of the minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), inhibition of biofilm formation and its rupture, sorbitol and ergosterol assays, and association between this molecule and common antifungal drugs, amphotericin B and fluconazole. The test product inhibited all strains of C. albicans and C. parapsilosis, with a MIC ranging from 128 to 256 µg.mL-1, and a MFC of 512-1,024 µg.mL-1. It also inhibited up to 92% of biofilm formation and rupture of up to 87% of preformed biofilm. 2-chloro-N-phenylacetamide did not promote antifungal activity through binding to cellular membrane ergosterol nor it damages the fungal cell wall. Antagonism was observed when combining this substance with amphotericin B and fluconazole. The substance exhibited significant antifungal activity by inhibiting both planktonic cells and biofilm of fluconazole-resistant strains. Its combination with other antifungals should be avoided and its mechanism of action remains to be established.

No atual contexto de patógenos fúngicos resistentes emergentes tais como Candida albicans e Candida parapsilosis, a descoberta de novos agentes antifúngicos é uma questão urgente. Esta pesquisa teve como objetivo avaliar o potencial antifúngico da 2-cloro-N-fenilacetamida contra cepas clínicas de C. albicans e C. parapsilosis resistentes a fluconazol. A atividade antifúngica da substância foi avaliada in vitro através da determinação da concentração inibitória mínima (CIM), concentração fungicida mínima (CFM), ruptura e inibição da formação de biofilme, ensaios de sorbitol e ergosterol, e associação entre esta molécula e antifúngicos comuns, anfotericina B e fluconazol. O produto teste inibiu todas as cepas de C. albicans e C. parapsilosis, com uma CIM variando de 128 a 256 µg.mL-1, e uma CFM de 512-1,024 µg.mL-1. Também inibiu até 92% da formação de biofilme e causou a ruptura de até 87% de biofilme pré-formado. A 2-cloro-N-fenilacetamida não promoveu atividade antifúngica pela ligação ao ergosterol da membrana celular fúngica, tampouco danificou a parede celular. Antagonismo foi observado ao combinar esta substância com anfotericina B e fluconazol. A substância exibiu atividade antifúngica significativa ao inibir tanto as células planctônicas quanto o biofilme das cepas resistentes ao fluconazol. Sua combinação com outros antifúngicos deve ser evitada e seu mecanismo de ação deve ser estabelecido.

Antifungal activity of 2-chloro-N-phenylacetamide: a new molecule with fungicidal and antibiofilm activity against fluconazole-resistant Candida spp

Abstract In the current context of emerging drug-resistant fungal pathogens such as Candida albicans and Candida parapsilosis, discovery of new antifungal agents is an urgent matter. This research aimed to evaluate the antifungal potential of 2-chloro-N-phenylacetamide against fluconazole-resistant clinical strains of C. albicans and C. parapsilosis. The antifungal activity of 2-chloro-N-phenylacetamide was evaluated in vitro by the determination of the minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), inhibition of biofilm formation and its rupture, sorbitol and ergosterol assays, and association between this molecule and common antifungal drugs, amphotericin B and fluconazole. The test product inhibited all strains of C. albicans and C. parapsilosis, with a MIC ranging from 128 to 256 µg.mL-1, and a MFC of 512-1,024 µg.mL-1. It also inhibited up to 92% of biofilm formation and rupture of up to 87% of preformed biofilm. 2-chloro-N-phenylacetamide did not promote antifungal activity through binding to cellular membrane ergosterol nor it damages the fungal cell wall. Antagonism was observed when combining this substance with amphotericin B and fluconazole. The substance exhibited significant antifungal activity by inhibiting both planktonic cells and biofilm of fluconazole-resistant strains. Its combination with other antifungals should be avoided and its mechanism of action remains to be established.

Resumo No atual contexto de patógenos fúngicos resistentes emergentes tais como Candida albicans e Candida parapsilosis, a descoberta de novos agentes antifúngicos é uma questão urgente. Esta pesquisa teve como objetivo avaliar o potencial antifúngico da 2-cloro-N-fenilacetamida contra cepas clínicas de C. albicans e C. parapsilosis resistentes a fluconazol. A atividade antifúngica da substância foi avaliada in vitro através da determinação da concentração inibitória mínima (CIM), concentração fungicida mínima (CFM), ruptura e inibição da formação de biofilme, ensaios de sorbitol e ergosterol, e associação entre esta molécula e antifúngicos comuns, anfotericina B e fluconazol. O produto teste inibiu todas as cepas de C. albicans e C. parapsilosis, com uma CIM variando de 128 a 256 µg.mL-1, e uma CFM de 512-1,024 µg.mL-1. Também inibiu até 92% da formação de biofilme e causou a ruptura de até 87% de biofilme pré-formado. A 2-cloro-N-fenilacetamida não promoveu atividade antifúngica pela ligação ao ergosterol da membrana celular fúngica, tampouco danificou a parede celular. Antagonismo foi observado ao combinar esta substância com anfotericina B e fluconazol. A substância exibiu atividade antifúngica significativa ao inibir tanto as células planctônicas quanto o biofilme das cepas resistentes ao fluconazol. Sua combinação com outros antifúngicos deve ser evitada e seu mecanismo de ação deve ser estabelecido.

Association study between ceftriaxone and a synthetic amide against strains of Pseudomonas aeruginosa.

Pseudomonas aeruginosa is a non-lactose fermenting Gram-negative bacteria responsible for causing numerous nosocomial infections. The present research aimed to analyze the anti-Pseudomonas aeruginosa potential of 2-Chloro-N-(4-fluoro-3-nitrophenyl)acetamide (A8). The antibacterial potential of A8 was evaluated from the Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Association using the checkerboard method. MIC and MBC values were 512 µg/mL for all P. aeruginosa strains evaluated, demonstrating predominantly bactericidal activity. Furthermore, when A8 was associated with the drug ceftriaxone, pharmacological additivity and indifference were evidenced. In this sense, the synthetic amide was interesting, since it demonstrates the potential to become a possible candidate for an antimicrobial drug.

Phase transitions of L-histidinium hydrogen oxalate crystal under high pressures investigated by Raman spectroscopy.

L-histidinium hydrogen oxalate (L-HisH)(HC2O4) crystal is formed from amino acid. L-histidine with oxalic acid whose vibrational high pressures behavior have not yet been investigated in the literature. Here we synthesized (L-HisH)(HC2O4) crystal by slow solvent evaporation method in a 1:1 ratio of L-histidine and oxalic acid. In addition, a vibrational study of (L-HisH)(HC2O4) crystal as a function of pressure was performed via Raman spectroscopy in the pressure range of 0.0-7.3 GPa. From analysis of the behavior of the bands within 1.5-2.8 GPa, characterized by the disappearance of lattice modes, the occurrence of a conformational phase transition was noted. A second phase transition, now from structural type, close to 5.1 GPa was observed due to the incidence of considerable changes in lattice and internal modes, mainly in vibrational modes related to imidazole ring motions.

Antifungal activity of 2-chloro-N-phenylacetamide: a new molecule with fungicidal and antibiofilm activity against fluconazole-resistant Candida spp.

In the current context of emerging drug-resistant fungal pathogens such as Candida albicans and Candida parapsilosis, discovery of new antifungal agents is an urgent matter. This research aimed to evaluate the antifungal potential of 2-chloro-N-phenylacetamide against fluconazole-resistant clinical strains of C. albicans and C. parapsilosis. The antifungal activity of 2-chloro-N-phenylacetamide was evaluated in vitro by the determination of the minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), inhibition of biofilm formation and its rupture, sorbitol and ergosterol assays, and association between this molecule and common antifungal drugs, amphotericin B and fluconazole. The test product inhibited all strains of C. albicans and C. parapsilosis, with a MIC ranging from 128 to 256 µg.mL-1, and a MFC of 512-1,024 µg.mL-1. It also inhibited up to 92% of biofilm formation and rupture of up to 87% of preformed biofilm. 2-chloro-N-phenylacetamide did not promote antifungal activity through binding to cellular membrane ergosterol nor it damages the fungal cell wall. Antagonism was observed when combining this substance with amphotericin B and fluconazole. The substance exhibited significant antifungal activity by inhibiting both planktonic cells and biofilm of fluconazole-resistant strains. Its combination with other antifungals should be avoided and its mechanism of action remains to be established.

High-pressures study by Raman spectroscopy and DFT calculations of L-tyrosine hydrobromide crystal.

The high-pressure Raman spectra of L-tyrosine hydrobromide crystal (LTHBr) were obtained from 1.0 atm to 8.1 GPa in the 100-3200 cm-1 spectral region. The structural conformation and dimensions of the monoclinic unit cell were estimated using the powder X-ray diffraction (PXRD) method and Rietveld refinement using the GSAS program. At atmospheric pressure, the Raman spectrum was obtained in the spectral range of 100-3200 cm-1 and the assignment of the normal modes based on density functional theory calculations was provided. Large wavenumber shifts of modes at 106, 123, and 157 were observed, which were interpreted as the large displacement of the atoms, making the molecule a flexible structure. The change in the slope (dÉ· / dP) of these bands between the pressures of 3.0 and 4.0 GPa and the appearance of a mode of low wavenumber indicate the occurrence of a structural phase transition. A band initially observed at 181 cm-1 in the spectrum recorded at 0.7 GPa change the relative intensity with a band at 280 cm-1 (recorded at 5.8 GPa), indicating a conformational transition. In the region of the internal modes, the spectra show changes that reinforce the conformational phase transition since the bands initially at 1247 and 1264 cm-1 observed at 1.0 GPa have their intensities reversed, and at 3.0 GPa it is observed the fusion of the bands at 1264 and 1290 cm-1 (values recorded at ambient pressure). Thus, we can assume that the LTHBr crystal has undergone a structural phase transition and a conformational phase transition in the pressure range investigated.

Pressure-induced phase transition in Glycinium maleate crystal.

The multicomponent glycinium maleate single crystal was grown by the slow evaporation method. The crystal was submitted to pressures ranging from 1 atm to 5.6 GPa and Raman spectroscopy was used as a spectroscopic probe. The modifications of relative intensity bands related to the lattice modes at 0.3 GPa were associated with rearrangements of hydrogen bonds. Moreover, between 1.7 and 4.8 GPa the Raman results indicate that the crystal experience a long structural phase transition, which was confirmed by PCA analysis. DFT calculations gave us more precision in the assignments of modes. The behavior of the internal modes under pressure showed that the maleic acid molecule undergoes greater modifications than glycine amino acid. All observed modifications were reversible when the pressure was released.

Raman spectroscopy of captopril crystals under low-temperature conditions.

The polymorphism is a characteristic of several active principles, and can affect the bioavailability of a drug. Among the drugs used in the treatment of heart diseases, captopril is one of the most widely used in the world. Despite the knowledge of vibrational properties of captopril under high temperature and under high pressure, a lack of information impedes the understanding of the substance in the crystal form at low temperatures. In this research, we investigated the vibrational properties of captopril crystals under cryogenic conditions in the 300-8 K interval using Raman spectroscopy. By observing the behavior of the inter- and intra-molecular vibrations it was possible to infer that the captopril molecules suffered a rearranging into the unit cell due slight orientational changes mainly involving CH⋯O hydrogen bonds. The phenomenon occurs in a large temperature range. However, the observed changes do not suggest the occurrence of a structural phase transition and the Raman spectra indicate that the trans conformation is recorded down to the lowest temperature available in the experiments.

In silico prediction of the functional and structural consequences of the non-synonymous single nucleotide polymorphism A122V in bovine CXC chemokine receptor type 1 / Predição in silico das consequências funcionais e estruturais do polimorfismo de nucleotídeo único não-sinônimo A122V no receptor de quimiocina CXC do tipo I bovino

Abstract The current study aimed to assess whether the A122V causal polymorphism promotes alterations in the functional and structural proprieties of the CXC chemokine receptor type 1 protein (CXCR1) of cattle Bos taurus by in silico analyses. Two amino acid sequences of bovine CXCR1 was selected from database UniProtKB/Swiss-Prot: a) non-polymorphic sequence (A7KWG0) with alanine (A) at position 122, and b) polymorphic sequence harboring the A122V polymorphism, substituting alanine by valine (V) at same position. CXCR1 sequences were submitted as input to different Bioinformatics' tools to examine the effects of this polymorphism on functional and structural stabilities, to predict eventual alterations in the 3-D structural modeling, and to estimate the quality and accuracy of the predictive models. The A122V polymorphism exerted tolerable and non-deleterious effects on the polymorphic CXCR1, and the predictive structural model for polymorphic CXCR1 revealed an alpha helix spatial structure typical of a receptor transmembrane polypeptide. Although higher variations in the distances between pairs of amino acid residues at target-positions are detected in the polymorphic CXCR1 protein, more than 97% of the amino acid residues in both models were located in favored and allowed conformational regions in Ramachandran plots. Evidences has supported that the A122V polymorphism in the CXCR1 protein is associated with increased clinical mastitis incidence in dairy cows. Thus, the findings described herein prove that the replacement of the alanine by valine amino acids provokes local conformational changes in the A122V-harboring CXCR1 protein, which could directly affect its post-translational folding mechanisms and biological functionality.

Resumo O presente estudo objetivou avaliar se o polimorfismo causal A122V promove alterações nas propriedades funcionais e estruturais da proteína receptora de quimiocina CXC do tipo 1 (CXCR1) de bovino Bos taurus por análises in silico. Duas sequências de aminoácidos da CXCR1 bovina foram selecionadas a partir do banco de dados UniProtKB/Swiss-Prot: a) sequência não-polimórfica (A7KWG0) contendo alanina (A) na posição 122, e b) sequência polimórfica carreando o polimorfismo A122V, causando a substituição de alanina por valina (V) na mesma posição. As sequências CXCR1 foram analisadas por diferentes ferramentas de Bioinformática para examinar o efeito desse polimorfismo sobre sua estabilidade, função e estrutura, predizer eventuais alterações na sua modelagem estrutural 3-D, bem como estimar a qualidade dos modelos preditos. O polimorfismo A122V exerceu efeitos toleráveis e não-deletérios sobre a CXCR1 polimórfica, apresentando um modelo estrutural de alfa-hélice típico de uma proteína receptora transmembranar para ambas as proteínas. Embora maiores variações nas distâncias entre os pares de aminoácidos nas posições-alvo tenham sido detectadas na proteína polimórfica, mais do que 97% dos aminoácidos em ambos os modelos foram situados em regiões ditas favoráveis e permitidas nos diagramas de Ramachandran. Evidências sustentam que o polimorfismo de nucleotídeo único A122V na proteína receptora CXCR1 está associado à aumentada incidência de mastite clínica em vacas leiteiras. Assim, as descobertas descritas aqui comprovam que a substituição do aminoácido alanina por valina provoca mudanças conformacionais locais na proteína CXCR1 polimórfica, que podem estar diretamente afetando seus mecanismos de enovelamento pós-traducionais e sua função biológica.

Pressure-induced phase transitions in DL-glutamic acid monohydrate crystal.

DL-glutamic acid monohydrate crystal was synthesized from an aqueous solution by slow evaporation technique. The crystal was submitted to high-pressure (1 atm-14.3 GPa) to investigate its vibrational behavior and the occurrence of phase transitions. We performed Raman spectroscopy as probe and through the analysis of the spectra we discovered three structural phase transitions. The first one occurs around 0.9 GPa. In this phase transition, glutamic acid molecules suffer modifications in their conformations while water molecules are less affected. The second phase transition at 4.8 GPa involves conformational changes related to CO2-, NH3+ units and the water molecules, while the third one, between 10.9 and 12.4 GPa, involves motions of several parts of the glutamic acid as well as the water molecules. Considering the dynamic of high pressure, the second phase of DL-glutamic acid monohydrate crystal presented a better stability compared with the second phase of its polymorphs α and ß L-glutamic acid. In addition, water molecules seem to play important role on this structural stability. All changes are reversible.

In silico prediction of the functional and structural consequences of the non-synonymous single nucleotide polymorphism A122V in bovine CXC chemokine receptor type 1.

The current study aimed to assess whether the A122V causal polymorphism promotes alterations in the functional and structural proprieties of the CXC chemokine receptor type 1 protein (CXCR1) of cattle Bos taurus by in silico analyses. Two amino acid sequences of bovine CXCR1 was selected from database UniProtKB/Swiss-Prot: a) non-polymorphic sequence (A7KWG0) with alanine (A) at position 122, and b) polymorphic sequence harboring the A122V polymorphism, substituting alanine by valine (V) at same position. CXCR1 sequences were submitted as input to different Bioinformatics' tools to examine the effects of this polymorphism on functional and structural stabilities, to predict eventual alterations in the 3-D structural modeling, and to estimate the quality and accuracy of the predictive models. The A122V polymorphism exerted tolerable and non-deleterious effects on the polymorphic CXCR1, and the predictive structural model for polymorphic CXCR1 revealed an alpha helix spatial structure typical of a receptor transmembrane polypeptide. Although higher variations in the distances between pairs of amino acid residues at target-positions are detected in the polymorphic CXCR1 protein, more than 97% of the amino acid residues in both models were located in favored and allowed conformational regions in Ramachandran plots. Evidences has supported that the A122V polymorphism in the CXCR1 protein is associated with increased clinical mastitis incidence in dairy cows. Thus, the findings described herein prove that the replacement of the alanine by valine amino acids provokes local conformational changes in the A122V-harboring CXCR1 protein, which could directly affect its post-translational folding mechanisms and biological functionality.

High pressure Raman scattering of DL­isoleucine crystals and DFT calculations.

DL­isoleucine single crystals were grown by the slow evaporation method at ambient temperature. Their vibrational properties were studied at ambient temperature as a function of pressure by Raman scattering. At ambient conditions the mode assignment was done in terms of the Potential Energy Distribution (PED) through density functional theory calculations. Both nitrogen and neon were used as pressure transmitting media. The pressure-dependent investigation shows modifications in the Raman spectra recorded between 30 and 3200 cm-1 that were interpreted as phase transitions undergone by the crystal between 1.3 and 1.9 GPa and between 3.6 and 5.1 GPa. Finally, stress was simulated on the unit cell of the crystal from ambient up to 5.0 GPa.

Immunoexpression of Heat Shock Protein 70, Glypican 3, Glutamine Synthetase, and Beta-Catenin in Hepatocellular Carcinoma After Liver Transplantation: Association Between Positive Glypican 3 and Beta-Catenin With the Presence of Larger Nodules.

BACKGROUND: Hepatocellular carcinoma (HCC) is the 6th leading cause of cancer worldwide. Its recurrence ranges from 6% to 26%. In the literature, many factors are associated with higher risk of recurrence, without a clear definition of the best method that could predict this highly lethal event. OBJECTIVE: The aim of this study was to evaluate the immunoexpression of immunohistochemical markers: HSP70, glypican 3, glutamine synthetase, and beta-catenin, as well as studying their association with tumor characteristics and prognosis of patients undergoing liver transplantation for HCC. METHODS: We studied 90 patients who underwent liver transplantation from 1998 to 2012. Afterwards we evaluated factors related to survival, tumor recurrence, and the correlation of expression of the immunohistochemical markers. RESULTS: Immunohistochemical marker glutamine synthetase showed a positive trend toward better survival. HSP70-positive patients had a higher prevalence of histologic grade III. Patients with positive glypican 3 showed larger lesions and a higher number with AFP >200 ng/mL. Patients with positive beta-catenin showed larger nodules and more with histologic grade III. The association between beta-catenin and glypican 3 showed positive association with larger nodules. CONCLUSIONS: Most of the markers studied had a correlation with at least one of the variables studied, confirming our hypothesis that these markers can indeed assist in assessing the prognosis of patients undergoing liver transplantation for HCC.

In silico prediction of the functional and structural consequences of the non-synonymous single nucleotide polymorphism A122V in bovine CXC chemokine receptor type 1

Abstract The current study aimed to assess whether the A122V causal polymorphism promotes alterations in the functional and structural proprieties of the CXC chemokine receptor type 1 protein (CXCR1) of cattle Bos taurus by in silico analyses. Two amino acid sequences of bovine CXCR1 was selected from database UniProtKB/Swiss-Prot: a) non-polymorphic sequence (A7KWG0) with alanine (A) at position 122, and b) polymorphic sequence harboring the A122V polymorphism, substituting alanine by valine (V) at same position. CXCR1 sequences were submitted as input to different Bioinformatics tools to examine the effects of this polymorphism on functional and structural stabilities, to predict eventual alterations in the 3-D structural modeling, and to estimate the quality and accuracy of the predictive models. The A122V polymorphism exerted tolerable and non-deleterious effects on the polymorphic CXCR1, and the predictive structural model for polymorphic CXCR1 revealed an alpha helix spatial structure typical of a receptor transmembrane polypeptide. Although higher variations in the distances between pairs of amino acid residues at target-positions are detected in the polymorphic CXCR1 protein, more than 97% of the amino acid residues in both models were located in favored and allowed conformational regions in Ramachandran plots. Evidences has supported that the A122V polymorphism in the CXCR1 protein is associated with increased clinical mastitis incidence in dairy cows. Thus, the findings described herein prove that the replacement of the alanine by valine amino acids provokes local conformational changes in the A122V-harboring CXCR1 protein, which could directly affect its post-translational folding mechanisms and biological functionality.

Resumo O presente estudo objetivou avaliar se o polimorfismo causal A122V promove alterações nas propriedades funcionais e estruturais da proteína receptora de quimiocina CXC do tipo 1 (CXCR1) de bovino Bos taurus por análises in silico. Duas sequências de aminoácidos da CXCR1 bovina foram selecionadas a partir do banco de dados UniProtKB/Swiss-Prot: a) sequência não-polimórfica (A7KWG0) contendo alanina (A) na posição 122, e b) sequência polimórfica carreando o polimorfismo A122V, causando a substituição de alanina por valina (V) na mesma posição. As sequências CXCR1 foram analisadas por diferentes ferramentas de Bioinformática para examinar o efeito desse polimorfismo sobre sua estabilidade, função e estrutura, predizer eventuais alterações na sua modelagem estrutural 3-D, bem como estimar a qualidade dos modelos preditos. O polimorfismo A122V exerceu efeitos toleráveis e não-deletérios sobre a CXCR1 polimórfica, apresentando um modelo estrutural de alfa-hélice típico de uma proteína receptora transmembranar para ambas as proteínas. Embora maiores variações nas distâncias entre os pares de aminoácidos nas posições-alvo tenham sido detectadas na proteína polimórfica, mais do que 97% dos aminoácidos em ambos os modelos foram situados em regiões ditas favoráveis e permitidas nos diagramas de Ramachandran. Evidências sustentam que o polimorfismo de nucleotídeo único A122V na proteína receptora CXCR1 está associado à aumentada incidência de mastite clínica em vacas leiteiras. Assim, as descobertas descritas aqui comprovam que a substituição do aminoácido alanina por valina provoca mudanças conformacionais locais na proteína CXCR1 polimórfica, que podem estar diretamente afetando seus mecanismos de enovelamento pós-traducionais e sua função biológica.

High pressure Raman spectra of monoglycine nitrate single crystal.

Single crystal of monoglycine nitrate has been studied by Raman spectroscopy under high pressures up to 5.5 GPa. The results show changes in lattice modes in the pressure ranges of 1.1-1.6 GPa and 4.0-4.6 GPa. The first change occurs with appearance of bands related to the lattice modes as well as discontinuity in the slope of dΩ/dP of these modes. Moreover, bands associated with the skeleton of glycine suggest that the molecule undergoes conformational modifications. The appearance of a strong band at 55 cm(-1) point to a second phase transition associated with the lattice modes, while the internal modes remain unchanged. These anomalies are probably due to rearrangement of hydrogen bonds. Additionally, decompression to ambient pressure shows that the phase transitions are reversible. Finally, the results show that the nitrate anions play an important role on the stability of the monoglycine nitrate crystal.

Rizatriptan vs. rizatriptan plus trimebutine for the acute treatment of migraine: a double-blind, randomized, cross-over, placebo-controlled study.

Gastroparesis frequently happens during migraine attacks, postponing the onset of action of orally administered drugs. Furthermore, triptans seem to work better in the earlier phases of the migraine attacks. Therefore, associating a gastrokinetic drug with a triptan may translate into better efficacy and higher consistency of response. Trimebutine is an opioid derivative with exclusive action on receptors of the Meissner and Auerbach plexus throughout the digestive tube. It has no absorption or central penetration. Herein we contrast the combination of rizatriptan plus trimebutine with rizatriptan alone in the acute treatment of migraine. Forty patients with migraine consecutively seen in our clinic were randomized to treat two consecutive moderate or severe attacks with one tablet of 10 mg rizatriptan plus one capsule of 200 mg trimebutine and two attacks with the same triptan and placebo, in counterbalanced order. We collected information on the severity of the attack, as well as presence of nausea and photophobia at the time of drug intake, and after 1, 2 and 4 h. Recurrence and adverse events were also contrasted. Sixty-four attacks were treated with each drug regimen. At 1 h postdose, 30 (46.8%) of 64 attacks treated with the combination resolved completely, vs. eight (12.5%) of the rizatriptan-treated attacks, a difference of 34% (P < 0.01). At 2 h postdose, 47 (73.4%) attacks treated with the combination vs. 20 (31.2%) of those treated with rizatriptan alone resolved completely, a difference of 42% (95% confidence interval 26, 58, P < 0.001). Regarding nausea and photophobia, the combination was also associated with significantly better response. Recurrence was similar among the two drug regimens, as well as adverse events. The combination rizatriptan and trimebutine is more effective than rizatriptan alone. The combination does not increase adverse events or recurrence of pain.

Relative feeding specialization may depress ontogenetic, seasonal, and sexual variations in diet: the endemic lizard Cnemidophorus littoralis (Teiidae).

We investigated the feeding habits of the teiid lizard Cnemidophorus littoralis in the markedly seasonal habitat of Restinga da Barra de Maricá (22 degrees 57'S, 43 degrees 50'W), Rio de Janeiro State, Brazil, to evaluate to what extent its diet is ontogenetically, sexually, and/or seasonally conservative. Lizard stomach contents were analyzed, identified, counted, estimated for volume (in mm3), and grouped in four classes (active, sedentary, and clumped preys, and plant material). The relative contribution of each food class to the total prey volume consumed by adult males and females and juveniles was compared in three ways: between juveniles and adults, sexes, and seasons (wet and dry). Sexual dimorphism in head size was tested by comparing head width and jaw length using analysis of covariance (ANCOVA). Isopterans were the most important prey item, occurring in 93% of the lizard stomachs examined and corresponding to 96.4% of total prey content and 69.7% of total prey volume. They occurred in high frequencies in the stomachs of C. littoralis throughout all study months. We found no sexual, ontogenetic, or seasonal differences in C. littoralis diet although the sexes differed significantly in head width. We concluded that isopterans are the main item in the diet of C. littoralis in Restinga da Barra de Maricá, both for juveniles and adults. The lack of seasonal, sexual, or ontogenetic variation in its diet results from the massive consumption of these insects. Isopterans are small, occur in clumps, and are available year-round, and thus are an advantageous food item for the active forager C. littoralis. We also found sexual dimorphism in the head size of C. littoralis: males have wider heads than females. This dimorphism, however, does not seem to be related with the diet of the species, and is probably a result of sexual selection.

Relative feeding specialization may depress ontogenetic, seasonal, and sexual variations in diet: the endemic lizard Cnemidophorus littoralis (Teiidae)

We investigated the feeding habits of the teiid lizard Cnemidophorus littoralis in the markedly seasonal habitat of Restinga da Barra de Maricá (22º57'S, 43º50'W), Rio de Janeiro State, Brazil, to evaluate to what extent its diet is ontogenetically, sexually, and/or seasonally conservative. Lizard stomach contents were analyzed, identified, counted, estimated for volume (in mm ), and grouped in four classes (active, sedentary, and clumped preys, and plant material). The relative contribution of each food class to the total prey volume consumed by adult males and females and juveniles was compared in three ways: between juveniles and adults, sexes, and seasons (wet and dry). Sexual dimorphism in head size was tested by comparing head width and jaw length using analysis of covariance (ANCOVA). Isopterans were the most important prey item, occurring in 93 percent of the lizard stomachs examined and corresponding to 96.4 percent of total prey content and 69.7 percent of total prey volume. They occurred in high frequencies in the stomachs of C. littoralis throughout all study months. We found no sexual, ontogenetic, or seasonal differences in C. littoralis diet although the sexes differed significantly in head width. We concluded that isopterans are the main item in the diet of C. littoralis in Restinga da Barra de Maricá, both for juveniles and adults. The lack of seasonal, sexual, or ontogenetic variation in its diet results from the massive consumption of these insects. Isopterans are small, occur in clumps, and are available year-round, and thus are an advantageous food item for the active forager C. littoralis. We also found sexual dimorphism in the head size of C. littoralis: males have wider heads than females. This dimorphism, however, does not seem to be related with the diet of the species, and is probably a result of sexual selection

Cluster headache associated with sleep apnoea.

This study of sleep changes in patients with cluster headache (CH) was conducted in view of the nocturnal predominance of this condition, the efficacy of oxygen and the fact that the attacks follow oxygen desaturation. Proposed mechanisms include impairment of carotid body activity secondary to hypothalamic vasomotor regulatory dysfunction. Sixteen patients with episodic CH and 29 healthy volunteers underwent nocturnal polysomnography. Five (31.3%) patients with episodic CH were found to have sleep apnoea (SA). Two patients with SA experienced two attacks during the study period. The attacks followed episodes of oxygen desaturation and were associated with REM sleep. In two patients with SA and CH, treatment with continuous positive airway pressure abolished their oxygen desaturation, sleep apnoeas and headaches. Our study confirmed the high percentage of CH associated with SA. We suggest that oxygen desaturation may be a trigger factor in some patients and play a role in the pathogenesis of CH.

Outros constituintes químicos de Diplotropis ferruginea Benth. (Fabaceae)

O extrato hexânico das cascas do caule de Diplotropis ferruginea Benth (Fabaceae), após procedimentos cromatográficos e fitoquímicos, forneceu o triterpeno lupeol, citado pela primeira vez em Diplotropis ferruginea, e etil-2-hidroxi-4-methoxi-6-propil-benzoate, descrito pela primeira vez em na literatura. As determinações estruturais desses compostos foram realizadas com base em análises espectroscópicas de ¹H e 13C NMR, bem como também por comparação com valores da literatura.

The hexane extract of the stem bark of Diplotropis ferruginea Benth (Fabaceae), after chromatografic and phytochemical procedures, yielded the triterpene lupeol, wich has been cited for the first time on Diplotropis ferruginea, and ethyl-2-hydroxy-4-methoxy-6-propyl-benzoate, described for the first time on literature. The structural determinations of these compounds were performed on the basis of ¹H and 13C NMR spectroscopic analysis as well as comparison with literature values.