Taxonomía de onicóforos de Santander, Colombia y termogravimetría, calorimetría de barrido diferencial y espectroscopía infrarroja de la secreción adhesiva (Onychophora: Peripatidae)

Velvet worm taxonomy from Santander, Colombia and thermogravimetry, differential scanning calorimetry and infrared spectroscopy of the adhesive secretion (Onychophora: Peripatidae). Onychophoran worms are terrestrial organisms that have changed relatively little since the mid-Cambrian. We collected Macroperipatus geagy in coffee plantations at "Hacienda El Roble", Santander, Colombia, and here redescribe the species based on 15 individuals. A digital three-dimensional reconstruction of the ventral side of the body indicates that the primary and accessory papillae lack a defined distribution pattern. Diagnostic characters: one main tooth and one accessory tooth in the outer jaw, and one main tooth, one accessory tooth and seven denticles in the internal jaw. Measurements: length (X=45.66 mm; SD=26.10), weight (X= 0.95 g; SD= 2.21) and number of lobopods (X= 28.13 pairs; SD= 1.30). We present a taxonomic key for six species of Macroperipatus. The liquid adhesive secretion lost 60% of the initial weight at 70 oC (solid: 13% close to 90 oC). The stability phase of the liquid secretion was within 90-280 oC (100 oC -205 oC in the solid secretion). The starting degradation temperature of the sample was 355 oC. Heat flow changes in the solid and liquid secretions were confirmed by the sample behavior during thermogravimetric analysis. The percentage of β sheets calculated by infrared spectrum was 59%. In comparison with Nephila spiders, the onychophoran secretion lost more weight and entered the phase of degradation at lower temperatures. This secondary structure of proteins gives the onychophoran adhesive secretion a tensile strength and extensibility similar to those of the silk produced by spiders for prey-capture. Rev. Biol. Trop. 57 (3): 567-588. Epub 2009 September 30.

Redescribimos taxonómicamente el gusano Macroperipatus geagy Bouvier 1899, a partir de 15 especímenes recolectados en los cafetales de hacienda El Roble, Santander, Colombia. De acuerdo con la reconstrucción en tres dimensiones de la superficie dorsal del cuerpo, las papilas primarias y accesorias de M. geagy se distribuyen sin formar un patrón determinado. Características diagnósticas: un diente accesorio y un diente principal en la mandíbula externa; y un diente principal, un diente accesorio y siete dentículos en la sierra de la mandíbula interna. Cuerpo: longitud (X=45.66; S=26.10 mm), peso (X= 0.95; S= 2.21) y pares de lobopodos (X= 28.13; S= 1.30). Se elaboró una clave para seis especies de Macroperipatus. La secreción adhesiva en estado líquido perdió 60% del peso inicial al alcanzar los 70 ºC, la muestra sólida perdió el 13% del peso cerca de los 90 ºC, la fase de estabilidad térmica de la secreción estuvo entre los 90 y 280 ºC en la secreción líquida y entre los 100 y 205 ºC en la sólida. La temperatura de inicio de la degradación de las muestras se registró a los 355 ºC. En comparación con la araña Nephila sp., el onicóforo perdió mayor porcentaje de peso y alcanzó la fase de degradación a temperaturas más bajas. Los cambios en el flujo de calor en la secreción adhesiva sólida y líquida de M. geagy fueron confirmados con el comportamiento de las muestras en el análisis de termogravimetría. La proporción de láminas beta calculado en el espectro infrarrojo de la secreción adhesiva fue del 59%. La presencia de este tipo de conformación de la estructura secundaria de las proteínas en la secreción adhesiva de M. geagy conferiría extensibilidad y resistencia a la tracción, en similitud con las fibras de seda tejidas por las arañas para depredación.

Estudo de metodologia analítica para a determinação do cetoconazol em formulações farmacêuticas / Study of analytical methodology for ketoconazole determination in pharmaceutical preparation

Cetoconazol é um antifúngico sintético, derivado imidazólico de amplo espectro de ação, efetivo no tratamento de infecções superficiais e sistêmicas. Foram estudadas diferentes metodologias para análise do cetoconazol em especialidades farmacêuticas diversas usando espectrofotometria no ultravioleta, no infravermelho e análise térmica. Os resultados mostram que a espectrofotometria ultravioleta é um método rápido, prático e econômico e apontam que outros métodos como a espectrofotometria no infravermelho e análise térmica são uma alternativa à análise do cetoconazol em diferentes especialidades farmacêuticas.

Ketoconazole is a synthetic broad-spectrum oral and topical antifungal drug derived from imidazole, effective in the treatment of superficial mycoses and systemic infections. In this study we have tested several methods to analyze ketoconazole in various pharmaceutical products containing this drug, employing techniques such as UV and IR spectrophotometry and thermal analysis. The results showed that UV spectrophotometryis a fast, practical and economical method and indicated that other methods, such as IR spectrophotometry and thermal analysis, could be good alternative methods for ketoconazole analysis in certain pharmaceutical forms.

UV-vis and IR spectroscopic studies of some 4-arylhydrazo-2-phenyl-2-oxazoline-5-one derivatives

The absorption spectra of some 4-arylhydrazo-2-phenyl-2-oxazoline-5-one derivatives, have been studied in organic solvents of different polarity. The diagnostic IR spectral bands are assigned and discussed in relation to molecular structure and hydrogen bond existing in the stable compounds in the hydrazo form. The presence of electron withdrawing group in the phenyl ring facilitates the charge migration and hence the proton transfer, thus the azohydrazo form may appear in these compounds, but the major compounds were in the hydrazo form. The fact that these compounds show evidence for intramolecular hydrogen bonding is in favor of the hydrazone structure, this fact excludes the possibility of azo structure. The electronic absorption bands are assigned to the corresponding electronic transitions and the effect of solvent parameters on the charge transfer energy [ECT] is investigated. Four absorbance bands appeared for hydrazones in the range 443-221 nm, the first band has Amax within the range 222-237 nm corresponding to the medium energy transition of the phenyl group e [1]La-[1]A]. The second band with [lambda]max at 243-257 nm is attributed to the low energy mm transition of the phenyl rings representing the [[1]Lb-[1]A] electronic state. The third band at 278-314 nm lies within the energy region for the mm excitation of the electrons of the hydrazo groups. The last band in the visible which has [lambda]max within the range 422-443 nm is considered as being due to an intramolecular charge transfer involving the whole molecule. Finally, the substitution effect was also studied

UV-visible and infrared spectroscopic studies of gamma irradiated commercial soda-lime silicate glasses

UV-visible and infrared absorption spectra of some selected commercial soda - lime - silicate glasses mixed with varied amounts of municipal glass cullet and doped with oxides of tin, manganese, and ceric before and after exposure to a high dose of gamma irradiation [5MR] were studied. XRF analysis showed that the municipal cullet contains high iron concentration and the results revealed that additions of [Mn + Ce + Sn] oxides produce colorless glasses even when containing high municipal cullet contents. It is generally observed that increasing the cullet content resulted in an optical spectrum consisting of three UV bands instead of two UV bands in case of low cullet content. The visible spectra reveal the resolution of two radiation induced bands at about 423 and 540 nm. Gamma irradiation also causes some of the absorption bands to be shifted in their positions. Experimental data are interpreted on the basis of current views on the spectroscopy of glasses

Synthesis, surface active properties of some amphoteric and anionic surfactants derived from long-chain mono alkyl malonate

A series of N.N-dimethyl-1-aminoethyl-2-amido-alkyl malonate and N, N-bis-carboxymethyl-1-aminoethyl-2-amido alkyl malonate surfactants based on fatly alcohol have been synthesized. The structure of these compounds was confirmed by elemental and spectroscopic analysis. The critical micelle concentration, efficiency, effectiveness, surface tension reduction at the air/water interface, CmC/C20 ratios. standard free energy of micellization, wetting and foam stability of the surfactants were determined. The results suggested that the minimum area/surfactants molecule [Amin] for the investigated compounds decreased with increasing the incorporated anionic group in the molecule of surfactant. It was shown that wetting and foaming characteristics of amphoteric surfactants were significantly better than those observed for anionic ones

Caracterização do fármaco hipoglicemiante glibenclamida / Characterization of the hypoglycemic drug glibenclamide

A glibenclamida (GLIB) é um fármaco de segunda geração, administrado por via oral na forma de comprimidos, utilizado para o tratamento de Diabetes mellitus. GLIB possui baixa solubilidade aquosa, o que pode levar a uma baixa liberação a partir de formas farmacêuticas sólidas no teste de dissolução e, portanto, a variabilidades no tratamento. Neste estudo, avaliam-se as características da matéria-prima GLIB, que podem influenciar o perfil de dissolução, e conseqüentemente, a biodisponibilidade, por meio de técnicas tais como, adsorção de nitrogênio, difração de raio laser, análise térmica, espectroscopia por IV/UV e difração de raios X.

Glibenclamide (GLIB) or glyburide, a second-generation hypoglycemic agent is orally used in the form of tablets for the treatment of diabetes mellitus. Bulk GLIB has a low aqueous solubility and it may yield low drug release in the dissolution test, causing variabilility in the treatment. This work evaluates the bulk GLIB features, which may influence drug release profile, hence, bioavailability, by means of techniques such as nitrogen sorption analysis, laser diffraction, thermal analysis, IV/UV spectroscopy and X-ray analysis.

Comparative study of the cuticular hydrocarbon in queens, workers and males of Ectatomma vizottoi (Hymenoptera, Formicidae) by Fourier transform-infrared photoacoustic spectroscopy

Fourier transform-infrared photoacoustic spectroscopy was applied for the first time, to our knowledge, to distinguish different castes of an ant species. The method was applied directly to the abdomen of queens, workers and males of Ectatomma vizottoi ants, without any special sample preparation. The absorption bands of secondary amide and hydrocarbons were identified; using these as variables in a canonical discriminant analysis we found significant differences between the castes. Queens have a greater hydrocarbon content than do workers and males, which is related to their function in the colony. This technique can be used to analyze and distinguish small chemical differences in biological systems, even in opaque samples.

Monitoring the injured brain in the intensive care unit.

The primary aim of managing patients with acute brain injury in the intensive care unit is to minimise secondary injury by maintaining cerebral perfusion and oxygenation. The mechanisms of secondary injury are frequently triggered by secondary insults, which may be subtle and remain undetected by the usual systemic physiological monitoring. Continuous monitoring of the central nervous system in the intensive care unit can serve two functions. Firstly it will help early detection of these secondary cerebral insults so that appropriate interventions can be instituted. Secondly, it can help to monitor therapeutic interventions and provide online feedback. This review focuses on the monitoring of intracranial pressure, blood flow to the brain (Transcranial Doppler), cerebral oxygenation using the methods of jugular bulb oximetry, near infrared spectroscopy and implantable sensors, and the monitoring of function using electrophysiological techniques.

Predicting the composition of gallstones by infrared spectroscopy.

AIM: To determine the composition of gallstones in South India by comparing visual assessment with graphic interpretation of infrared spectra. METHODS: Infrared spectroscopy (IRS) was used in qualitative analysis of 168 gallstones from Tamilnadu, Kerala and Karnataka and compared with visual interpretation. The spectrum of cholesterol, calcium bilirubinate and calcium carbonate for each stone was correlated with visual inspection. RESULTS: Fifty four percent of gallstones were of pigment variety, 43% were of mixed and the remaining 3% were cholesterol gallstones as categorised by visual interpretation. Based on infrared spectrocopic interpretation the percentages were 58%, 39% and 2% respectively. There was a good agreement between the visual inspection and IRS in classification of gallstones (Kappa value 85%; 95% CI 77-93%). CONCLUSION: Visual inspection of gallstones can predict the composition of gallstone with good accuracy and was comparable to infrared spectroscopic interpretation.

Metodología para estudios de estabilidad química en formulaciones de quitina / Methodology for chemical stability studies in chitin formulations

Se propuso combinar la gravimetría directa como método cuantitativo con la espectroscopia infrarroja como técnica cualitativa complementaria, con el objetivo de establecer la metodología para el seguimiento de la estabilidad química de la quitina como fármaco en diferentes formas farmacéuticas> suspensión, crema, supositorio. La determinación del contenido de quitina por técnicas gravimétricas se validó en cada caso según los parámetros> linealidad, precisión, exactitud y especificidad. El análisis cuantitativo mostró resultados satisfactorios con respecto al contenido de fármaco en el tiempo en todas las formulaciones evaluadas. Estos resultados fueron corroborados por los espectros infrarrojos, manifestándose que la quitina es el único producto retenido en los filtros y que desde el punto de vista químico no ha sufrido alteraciones transcurridos 2 a de estudio

Application of isotope-selective non-dispersive infrared spectrometry for the evaluation of the 13C-urea breath test: comparison with three concordant methods

The aim of this work was to compare the performance of isotope-selective non-dispersive infrared spectrometry (IRIS) for the 13C-urea breath test with the combination of the 14C-urea breath test (14C-UBT), urease test and histologic examination for the diagnosis of H. pylori (HP) infection. Fifty-three duodenal ulcer patients were studied. All patients were submitted to gastroscopy to detect HP by the urease test, histologic examination and 14C-UBT. To be included in the study the results of the 3 tests had to be concordant. Within one month after admission to the study the patients were submitted to IRIS with breath samples collected before and 30 min after the ingestion of 75 mg 13C-urea dissolved in 200 ml of orange juice. The samples were mailed and analyzed 11.5 (4-21) days after collection. Data were analyzed statistically by the chi-square and Mann-Whitney test and by the Spearman correlation coefficient. Twenty-six patients were HP positive and 27 negative. There was 100 per cent agreement between the IRIS results and the HP status determined by the other three methods. Using a cutoff value of delta-over-baseline (DOB) above 4.0 the IRIS showed a mean value of 19.38 (minimum = 4.2, maximum = 41.3, SD = 10.9) for HP-positive patients and a mean value of 0.88 (minimum = 0.10, maximum = 2.5, SD = 0.71) for negative patients. Using a cutoff value corresponding to 0.800 per cent CO2/weight (kg), the 14C-UBT showed a mean value of 2.78 (minimum = 0.89, maximum = 5.22, SD = 1.18) in HP-positive patients. HP-negative patients showed a mean value of 0.37 (minimum = 0.13, maximum = 0.77, SD = 0.17). IRIS is a low-cost, easy to manage, highly sensitive and specific test for H. pylori detection. Storing and mailing the samples did not interfere with the performance of the test.

Studies on the surface properties of human lymphocytes by photon correlation spectroscopy technique.

Electrokinetic behaviour of human lymphocytes was studied by photon correlation spectroscopy technique on laser IR-spectrometer. The electrophoretic mobilities (EPMs) were measured for peripheral blood lymphocytes (PBL) and CEM-C12 T cell line in 1:1 electrolyte at 22 degrees C. Plots of mobility vs ionic strength in the range 0.001-0.1 M were compared with theoretical curves calculated from (i) the Smoluchowsky formula, (ii) the simplified form of the Dukhin-Deryaguin equation which takes into account the fact that the mobility decreases due to the relaxation effect and (iii) the equation suggested by Donath and Pastushenko, which takes into account the influence of cell glycoprotein layer (GPL) on the EPM values. It has been found that the first two equations describe the experimental data with the assumption that surface charge density (sigma) decreases and width of the hydrodynamically immobile layer (L) increases with decreasing ionic strength; the relaxation effect turns out to be insignificant for the cell charges and sizes under consideration. In agreement with these findings, the third equation is approximately consistent with experimental data on the condition that GPL is allowed to expand with decreasing ionic strength, with simultaneous decrease of its full charge density (sigma(f)). The results are compared with relevant evidence for erythrocytes. The possible applications of the inferences arrived at in electrophoretic studies of cell behaviour are also discussed.

Synthesis and reactions of some derivatives of pyridaziny lthioglycolic acid hydrazide with possible antimicrobial activity

Substituted pyridazinyl-thiomethyl-1, 3, 4-oxadiazoles, some of their Mannich bases and their N-imido derivatives are reported. Some of these compounds are subjected to bacteriological screening. The structure of these new compounds are established on the basis of elemental analysis, IR and 1H-NMR

Monitoreo del dióxido de carbono / Monitoring of carbon dioxide

La capnografía se ha mostrado como una valiosa adquisición en el arsenal del anestesista, ya que puede alertarlo sobre situaciones potencialmente mortales, como mala colocación del tubo endotraqueal, desconexión del circuito en un paciente paralizado e hipertermia maligna, condiciones todas que si no sedetectan y tratan precozmente, llevan a un alata morbilidad y posiblemente también mortalidad. El empleo del capnógrafo es útil también en la ventilación artificial, permitiendo en forma individual regular el volumen corriente y volumen minuto utilizando la ETCO2 en lugar de normogramas por kilo de peso. Esto hace que actualmente se pueda efectivamente hablar de ventilación controlada. Esta técnica es de un aprendizaje de la fisiopatología respiratoria aplicada

Estudio químico del Heliotropium Curassavicum L que crece en Cuba / Chemical study of Heliotropium Curassavicum L growing in Cuba

Como parte del programa de tamizaje antitumoral de plantas cubanas del Departamento de Bioquímica del Instituto Nacional de Oncología y Radiobiología, se inició el estudio de la especie Heliotropium Curassavicum L, la que resultó activa en el tamizaje primario de leucemia, 1 210, y hepatoma, 22. Al realizar el estudio fitoquímico de la misma se aislaron los componentes mayoritarios heliocurassavicina y heliocurassavinina, los que fueron caracterizados espectroscópicamente

Estudio del dimeltilsulfxido (DMSO) y del Ion Amonio (NH+4) en sistemas zeoliticos por medio de las espectroscopias de masas, infrarrojo, resonancia paramagnetica electrónica y resonancia magnetica nuclear de pulsos / Study of the dimethyl sufoxide de (CDMSO) and the ammonia ions (NHT4) in zeolites systems by means to mass spectroscopy electronic paramagnetic resonance and paramagnetic pulse nuclear resonance

Fueron revisados los resultados de las investigaciones realizadas en las zeolitas, por medio de la espectroscopia de infrarrojo y las técnicas de análisis térmico diferencial y flashdesorption siendo imposible determinar la ubicación del ión amonio. El uso de la espectrometría de masa, hizo posible determinar el número de sitios de ubic ción del ión amonio en la red zeolitica y el tipo de acoplamiento con moléculas de agua y con la red. La espectroscopia de infrarrojo nos permitió separar las bandas de absorción debidas a las vibraciones del ión amonio perturbado por su contorno a la red zeolítica hidratada. De los resultados obtenidos por espectrometria de masas y espectroscopia de infrarrojo se concluyó que las muestras usadas, intercambiadas por iones amonio en medio acuoso, no son adecuadas para resonancia magnetica nuclear, dada la imposibilidad de deshidratar la muestra sin deamuzarla