RESUMEN
1. A series of experiments were carried out to study the effect of grit on broiler performance, gizzard development and fate of grit in the digestive tract. 2. In Experiment 1, performance, gizzard weight and content of grit in the gizzard of broiler chickens given access to granite-type grit was investigated. In Experiment 2, the effect of grit stones on performance and gizzard development was assessed in diets with or without whole wheat. 3. In Experiment 3, the effect of grit in the form of zeolite, granite or marble on gizzard development and digestive tract grinding and passage was studied in diets with or without whole wheat. 4. Grit stones had no effect on performance of broiler chickens, which may be explained by the fact that grit stones did not stimulate gizzard development to the same extent as with other structural materials. 5. The lack of stimulation is at least partly due to the fact that a majority of the grit stones eaten pass through the small intestine without being retained in the gizzard. 6. Grit in the form of marble reduced feed intake and weight gain.
Asunto(s)
Alimentación Animal/análisis , Pollos/fisiología , Dieta/veterinaria , Digestión , Molleja de las Aves/crecimiento & desarrollo , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Carbonato de Calcio/administración & dosificación , Pollos/crecimiento & desarrollo , Dióxido de Silicio/administración & dosificación , Aumento de Peso/efectos de los fármacos , Zeolitas/administración & dosificaciónRESUMEN
Las lesiones precursoras de malignidad (gastritis crónica atrófica, metaplasia intestinal y displasia leve), según lo demuestran múltiples estudios, están claramente relacionadas con el riesgo que presentan como predictoras del cáncer gástrico y más aún en nuestra región considerada como de alto riesgo de esta patología. Se realizó un estudio prospectivo descriptivo con 212 pacientes entre 11 y 89 años de edad procedentes de la zona amarilla del departamento de Nariño, atendidos en el Centro de Investigaciones de Enfermedades Digestivas (CIED) del Centro Hospital La Rosa dependiente de la ESE Pasto Salud a quienes se tomaron 7 biopsias de mucosa gástrica sometidas a un procesamiento y coloración especial de Giemsa modificado para detectar lesiones precursoras de malignidad y presencia de Helicobacter Pylori. La prevalencia para gastritis crónica atrófica antrocorporal fue de 38,6%, metaplasia intestinal 24,4% y displasia leve 1,5%; presencia de infección para Helicobacter pylori en gastritis crónica atrófica 73,5%, para metaplasia intestinal 52% y displasia leve 100%; en relación a la severidad de las lesiones precursoras de malignidad de acuerdo a la escala de OLGA, 11,5% se clasificó como estadios III y IV; a excepción de un solo caso clínico todos fueron Helicobacter Pylori positivos. Se pone en consideración de la comunidad médica el protocolo del CIED para seguimiento y vigilancia de las lesiones precursoras de malignidad tratando de demostrar que la mayor estrategia sigue siendo la prevención para el control del cáncer gástrico en las regiones de alto riesgo.
Atrophic chronic gastritis (ACG), intestinal metaplasia (IM) and mild dysplasia (MD)) are all precursor lesions which have been clearly demonstrated by many studies to be related to risks for development of gastric cancer (GC). This is especially true in our region which is considered to be a high risk area for this disease. We conducted a prospective study of 212 patients between the ages of 11 and 89 years who were from the yellow zone of Nariño. Patients were cared for in the Centro de Investigaciones de Enfermedades Digestivas (CIED - Center for the Investigation of Digestive Diseases) at the Centro Hospital la Rosa which is part of the public health care system of Pasto. Seven gastric mucosa biopsies were taken from each subject and stained with specially modified Giemsa stain to detect precursor lesions and the presence of Helicobacter pylori. The prevalence of ACG was 38.6%, the prevalence of IM was 24.4%, and the prevalence of MD was 1.5%. Prevalence of H. pylori infections among patients with ACG was 73.5% while among patients with IM it was 52%, but prevalence rose to 100% among patients with MD. When severity of precursor lesions on the OLGA-staging (Operative Link for Gastritis Assessment) scale was 11.5%, lesions were classified as stage III and IV. With one exception, all of these patients were H. pylori positive. We would like to ask the medical community to consider CIED's Follow-up and Monitoring Protocol for precursor lesions in order to demonstrate that the best strategy continues to be GC prevention in high risk regions.
Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Gastritis , Gastritis Atrófica , Metaplasia , Lesiones Precancerosas , Neoplasias GástricasRESUMEN
The 1983-1984 mass mortality event of Diadema antillarum affected more than 93% of the total Caribbean population. Although there are no records about the status of Diadema populations before and after die-off on Cuban reefs, anecdotal information suggests that populations were struck. We analyzed spatial variation in the abundance and size structure of D. antillarum in 22 reefs sites in Jardines de la Reina, from June 2004 to September 2005. Counts of Diadema were performed in five 30x2 m transects at each sampling site and sampling time, and test diameters were measured in September 2005 at the same fore reefs. Abundances were higher at reef crests (mean densities 0.08-2.18 ind./m2), while reef slope populations reached a maximum site level of 0.13 ind./m2 at only one site and showed values up to three orders of magnitude lower than those from reef crests. Highest abundance occurred at the west margin of major channels between keys where larval recruitment seems to be favored by local oceanographic features and facilitated by the abundance of Echinometra lucunter. The size frequency distribution of D. antillarum indicates that recruitment began to be noticeable three years before September 2005, suggesting these populations were depleted in the past and they are recovering now.
Asunto(s)
Antozoos , Erizos de Mar/clasificación , Animales , Cuba , Equinodermos/clasificación , Densidad de Población , Dinámica Poblacional , Estaciones del AñoRESUMEN
The 1983-1984 mass mortality event of Diadema antillarum affected more than 93% of the total Caribbean population. Although there are no records about the status of Diadema populations before and after die-off on Cuban reefs, anecdotal information suggests that populations were struck. We analyzed spatial variation in the abundance and size structure of D. antillarum in 22 reefs sites in Jardines de la Reina, from June 2004 to September 2005. Counts of Diadema were performed in five 30x2m transects at each sampling site and sampling time, and test diameters were measured in September 2005 at the same fore reefs. Abundances were higher at reef crests (mean densities 0.08-2.18 ind./m²), while reef slope populations reached a maximum site level of 0.13 ind./m² at only one site and showed values up to three orders of magnitude lower than those from reef crests. Highest abundance occurred at the west margin of major channels between keys where larval recruitment seems to be favored by local oceanographic features and facilitated by the abundance of Echinometra lucunter. The size frequency distribution of D. antillarum indicates that recruitment began to be noticeable three years before September 2005, suggesting these populations were depleted in the past and they are recovering now. Rev. Biol. Trop. 58 (2): 663-676. Epub 2010 June 02.
La mortalidad de Diadema antillarum en 1983-1984 afectó más del 93% de la población del Caribe. Aunque no existen datos publicados sobre el estado de sus poblaciones en arrecifes cubanos antes y después de la mortalidad, se conoce anecdóticamente que fueron afectadas. En el presente trabajo se analizan las variaciones espaciales de la abundancia y estructura de tallas de D. antillarum en 22 arrecifes frontales en Jardines de la Reina, para lo cual se realizaron cinco recorridos de 30x2m en cada sitio entre Junio de 2004 y Septiembre de 2005. Las densidades de Diadema fueron mayores en las crestas arrecifales (0.08-2.18 ind./m²) mientras que en las pendientes fueron hasta tres órdenes de magnitud menor y la densidad máxima fue 0.13 ind./m². Las crestas con mayor abundancia de Diadema están ubicadas en los márgenes de las grandes pasas existentes entre cayos donde el reclutamiento parece estar favorecido por las condiciones oceanográficas locales y facilitado por la abundancia de Echinometra lucunter. La distribución de frecuencia de tallas de Diadema sugiere que el reclutamiento comenzó a ser notable aproximadamente tres años antes del muestreo, indicando que en el pasado sus poblaciones estuvieron afectadas y ahora están recuperándose.
Asunto(s)
Animales , Antozoos , Erizos de Mar/clasificación , Cuba , Equinodermos/clasificación , Densidad de Población , Dinámica Poblacional , Estaciones del AñoRESUMEN
Trophic interactions of the six most abundant fish species in the artisanal fishery in two bays, central Mexican Pacific. We surveyed the trophic components in six species of Bahía de Navidad and Bahía de Chamela: Microlepidotus brevipinnis, Caranx caballus, Haemulon flaviguttatum, Lutjanus guttatus, L. argentiventris and Mulloidichthys dentatus. Two main seasonal periods were considered: 1) North Equatorial Counter Current NECC period influence (T1) and 2) California Current CC period influence (T2). In Bahía de Navidad 78 prey taxa were identified in the stomachs. From July to December (T1), 64 prey taxa were found, and from January to June (T2), 45 prey items. In Bahía de Chamela 93 prey items were identified; 74 during T1 and 60 during T2. The highest prey number was found in the stomachs of M. dentatus during T1 in Bahía de Navidad and the lowest prey number (7) was recorded in H. flaviguttatum in Bahía de Navidad in the same period. Crustaceans were the most frequently recorded prey items, followed by fishes, mollusks, polychaetes, and echinoderms in both seasonal periods and sites. The six fish species studied are considered as specialist feeders due the low values of the niche breadth index. There was little similarity among the diets. Rev. Biol. Trop. 58 (1): 383-397. Epub 2010 March 01.
Se analizaron los componentes tróficos de las seis especies de peces más importantes en la captura de la pesquería artesanal en las Bahía de Navidad y Chamela, ubicadas en la costa de Jalisco, México. Las especies estudiadas fueron Microlepidotus brevipinnis, Caranx caballus, Haemulon flaviguttatum, Lutjanus guttatus, Lutjanus argentiventris y Mulloidichthys dentatus. Se consideraron dos periodos de estudio de acuerdo a las pautas hidroclimáticas y los patrones de producción biológica en la zona: periodo de influencia de la Contracorriente Norecuatorial (T1), y periodo de influencia de la Corriente de California (T2). En Bahía de Navidad se identificaron 78 presas en total para las seis especies. En el periodo comprendido entre julio y diciembre (T1) se identificaron 64 presas y 45 de enero a junio (T2). En Bahía de Chamela se identificaron 93 presas, encontrando 74 presas en el periodo T1 y 60 presas para el periodo T2. El mayor número de presas se encontró en M. dentatus con 34 presas en el periodo T1 de Bahía de Chamela y el menor número fue en H. flaviguttatum en T1 de Bahía de Navidad con solo 7 presas. Los crustáceos fueron las presas de mayor presencia en la dieta, seguidos por peces, moluscos, poliquetos y equinodermos, en ambos periodos y sitios de muestreo. Las seis especies analizadas se consideran como especialistas, dados los bajos valores del índice de amplitud de nicho en ambos periodos y sitios de muestreo.
Asunto(s)
Animales , Peces/fisiología , Contenido Digestivo , Explotaciones Pesqueras , Conducta Alimentaria/fisiología , Peces/clasificación , México , Estaciones del AñoRESUMEN
Reproduction of the fish Gymnothorax equatorialis (Pisces: Muraenidae) in Jalisco and Colima, Mexico. A total of 707 Gymnothorax equatorialis were collected monthly in the Jalisco and Colima coast, Mexico, from December 1995 to December 1998 and from August to November 1999, in order to determine their reproduction patterns. Females outnumbered and had longer bodies (mean length 54.7 cm) than males (52.1 cm). The minimum, maximum and mean values of total fecundity were respectively 9 660, 99 992 and 32 029 eggs. The total body length at which 50 percent of individuals have ripe gonads (L50) was 43.7 cm for females and 42.7 cm TL for males. Ovaries had two main types of oocytes: small inmature in cromatin nucleolus phase (85.1 microm) and large mature in secundary vitellogenesis phase (701.6 microm). High numbers of spermatozoa were observed in the seminal tubes of ripe testicles, which presented a lobular development. Based in gonad features and temporal changes in the gonad-somatic index, it is concluded that G. equatorialis has two relatively short reproduction periods (at the middle and at the end of the year).
Asunto(s)
Anguilas/fisiología , Gónadas/crecimiento & desarrollo , Reproducción/fisiología , Animales , Anguilas/anatomía & histología , Anguilas/crecimiento & desarrollo , Femenino , Masculino , MéxicoRESUMEN
Reproduction of the fish Gymnothorax equatorialis (Pisces: Muraenidae) in Jalisco and Colima, Mexico. A total of 707 Gymnothorax equatorialis were collected monthly in the Jalisco and Colima coast, Mexico, from December 1995 to December 1998 and from August to November 1999, in order to determine their reproduction patterns. Females outnumbered and had longer bodies (mean length 54.7 cm) than males (52.1 cm). The minimum, maximum and mean values of total fecundity were respectively 9 660, 99 992 and 32 029 eggs. The total body length at which 50 percent of individuals have ripe gonads (L50) was 43.7 cm for females and 42.7 cm TL for males. Ovaries had two main types of oocytes: small inmature in cromatin nucleolus phase (85.1 microm) and large mature in secundary vitellogenesis phase (701.6 microm). High numbers of spermatozoa were observed in the seminal tubes of ripe testicles, which presented a lobular development. Based in gonad features and temporal changes in the gonad-somatic index, it is concluded that G. equatorialis has two relatively short reproduction periods (at the middle and at the end of the year).
Con el fin de analizar los aspectos reproductivos de Gymnothorax equatorialis se recolectaron mensualmente 707 organismos en las costas de Jalisco y Colima, México, de diciembre de 1995 a diciembre de 1998 y de agosto a diciembre de 1999. Las hembras fueron más numerosas y presentaron una longitud (54.7 cm) mayor a la de los machos (52.1 cm). La fecundidad total mínima fue de 9 660 huevos, la máxima de 99 992 y la media fue 32 029 huevos. La talla en la que el 50 % de los individuos presentan gónadas maduras (L50) fue de 43.7 cm de longitud total en hembras y de 42.7 cm en machos. Los ovarios presentaron dos tipos de ovocitos, los pequeños inmaduros en fase cromatina nucleolo (85.1 μm) y los grandes maduros en fase de vitelogénesis secundaria (701.6 μm). En el testículo maduro se observó una gran cantidad de espermatozoides en el tubo seminal y el desarrollo del testículo es de tipo lobular. Con base en las características de las gónadas y la evolución temporal del índice gonadosomático, se concluye que G. equatorialis se reproduce dos veces al año (a mediados y finales del año).
Asunto(s)
Animales , Masculino , Femenino , Anguilas/fisiología , Gónadas/crecimiento & desarrollo , Reproducción/fisiología , Anguilas/anatomía & histología , Anguilas/crecimiento & desarrollo , MéxicoRESUMEN
1. The Australian plague locust, Chortoicetes terminifera, develops following rainfall in an environment dominated by two host plants, the annual Dactyloctenium radulans and the perennial Astrebla lappacea. This simple system provides an ideal opportunity to explore the relationship between plant quality, individual herbivore performance and population responses. 2. We compared the two grasses chemically and structurally, and the behavioural, physiological and developmental responses of locust nymphs to these diets. 3. The grasses appeared to be of similar nutritional quality in terms of their chemical composition, although they differed in their physical properties. Early instar nymphs performed equally well on both grasses. However, older nymphs consuming D. radulans developed faster, survived better and attained a higher body weight compared with those consuming A. lappacea. 4. The differences in performance by the older nymphs related to the rate and ratio of supply of carbohydrate and protein from the two grasses, with less carbohydrate being assimilated from A. lappacea than D. radulans per unit of protein assimilated. Experiments showed that these differences arose as a direct result of the physical barrier to nutrient extraction provided by cell walls and indirectly through the amount of water contained within each cell. Paradoxically, nitrogen did not limit performance in the traditional sense through shortage,but rather its relative excess in A. lappacea appeared to impede intake and assimilation of adequate carbohydrate. 5. As a consequence, we predict that the length of time D. radulans remains available following rainfall will influence plaguing dynamics, although not for the reasons previously thought. 6. The results highlight the need to consider nutrient balance and actual rates of supply (rather than simply measuring the chemical composition of the plant) when attempting to understand herbivore nutritional ecology.
Asunto(s)
Ecosistema , Metabolismo Energético/fisiología , Conducta Alimentaria/fisiología , Saltamontes/fisiología , Animales , Australia , Ninfa/fisiología , Poaceae , Dinámica Poblacional , LluviaRESUMEN
From 1994 to 2003, a total of 526 bitches of 99 different breeds were artificially inseminated in 685 estrus cycles with domestic (n = 353) or imported (n = 332) frozen-thawed semen from 368 males. The overall whelping rate was 73.1% and mean (+/- S.E.M.) litter size 5.7 +/- 0.1 pups. The whelping rate was higher after intrauterine insemination (75.0%; n = 665) than after intravaginal insemination (10.0%, n = 20; P < 0.05). Insemination at the optimal time resulted in a higher whelping rate (78%, n = 559; P < 0.01) and larger litter size (5.8 +/- 0.2; P < 0.05) than inseminations performed late or too late (55.7% and 4.5 +/- 0.5, n = 61). Two inseminations (n = 384) yielded a higher whelping rate (P < 0.05) and mean litter size (P < 0.01) than one insemination (n = 241), 78.1% and 6.0 +/- 0.2 and 70.5% and 5.1 +/- 0.2, respectively. For inseminations performed at the optimal time, however, the whelping rate was not significantly different for bitches inseminated twice (79.3%, n = 358) versus once (76.8%, n = 168), but the litter size was larger (6.0 +/- 0.2 and 5.3 +/- 0.3). Semen classified as of poor quality (progressive motility < 50% or percentage abnormal sperm > 20%) resulted in a lower whelping rate (P < 0.01) than semen classified as of good quality (progressive motility > or = 50% and percentage abnormal sperm < or = 20%), 61 and 77%, respectively. Small breeds (n = 50) had a smaller litter size (3.9 +/- 0.3; P < 0.01) than larger breeds (medium [5.7 +/- 0.3, n = 94], large [5.9 +/- 0.2, n = 295] or giant breeds [6.1 +/- 0.5, n = 62] [P < 0.01]). Bitches older than 6 years had a lower whelping rate (68.2%) than younger ones (77.0%; P < 0.05). The duration of pregnancy was longer (P < 0.01) for bitches with a litter size of < 3 pups (61.7 +/- 0. 4 days, n = 30) than for bitches with larger litters (60.5 +/- 0.1 days, n = 177). These results show the potential of transcervical intrauterine insemination for routine artificial insemination in dogs. The results with frozen semen inseminations were optimised by inseminating bitches < or = 6 years old 2 and 3 days after ovulation with semen of good quality from males < or = 8 years old.
Asunto(s)
Criopreservación/veterinaria , Perros/fisiología , Inseminación Artificial/veterinaria , Preservación de Semen/veterinaria , Animales , Animales Recién Nacidos , Cruzamiento , Criopreservación/métodos , Femenino , Inseminación Artificial/métodos , Inseminación Artificial/normas , Tamaño de la Camada , Masculino , Embarazo , Estudios Retrospectivos , Preservación de Semen/métodosRESUMEN
The difficulties traditionally faced by functional morphologists in representing and interpreting three-dimensional objects can now be mostly overcome using available laser and computer imaging technologies. A practical method for three-dimensional imaging of small mammalian teeth using confocal microscopy is reported. Moulding and casting of the teeth were first performed, followed by confocal fluorescence imaging. Accuracy and precision of the scanned structures were tested in morphometric studies by using a new technique to measure the noise in the scan of a three-dimensional surface, and linear and angular dimensions of the scans were compared with measurements made using traditional morphological tools. It is shown that measurements can be taken with less than 4% difference from the original object. Teeth of the microchiropteran bat Chalinolobus gouldii were scanned and measured to show the potential of the techniques. Methods for visualizing the small teeth in three-dimensional space, and animating the teeth in occlusion, show the power of this approach in aiding a three-dimensional understanding of the structure and function of teeth and other three-dimensional structures.
Asunto(s)
Microscopía Confocal/métodos , Diente/anatomía & histología , Animales , Pesos y Medidas Corporales , Quirópteros , Imagenología TridimensionalRESUMEN
HYPOTHESIS: A pattern of prehospital care combining advanced life support, physician staffing, and helicopter transport improves the outcome of patients with severe brain injuries, compared with combined expanded basic life support, nurse staffing, and ground transport. DESIGN: Inception cohort from the data set of a population-based, prospective study on major trauma. SETTING: Prehospital and hospital trauma systems of an Italian region. PATIENTS: All patients with major trauma (Injury Severity Score, >or=16) and severe head injury (Abbreviated Injury Scale score for the head, >or=4) rescued alive from March 1, 1998, to February 28, 1999, who received either form of care. Patients with self-inflicted injuries were excluded. The 184 patients who met the entry criteria were divided equally between care groups. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Mortality at 30 days and Glasgow Outcome Scale score of survivors. RESULTS: After verifying the comparability of the cohorts, no survival or disability benefit could be demonstrated (95% confidence interval [CI] of the odds ratio for mortality [helicopter/ambulance] [95% CI 1], 0.72 to 2.67; 95% CI of the difference in Glasgow Outcome Scale score medians between helicopter and ambulance groups [95% CI 2], 0.0 to 0.0). Similar results were derived from analyses restricted to the subgroups identified by low (Asunto(s)
Traumatismos Craneocerebrales/terapia
, Servicios Médicos de Urgencia/organización & administración
, Evaluación de Resultado en la Atención de Salud
, Adulto
, Ambulancias Aéreas
, Servicios Médicos de Urgencia/normas
, Femenino
, Escala de Consecuencias de Glasgow
, Humanos
, Puntaje de Gravedad del Traumatismo
, Italia
, Cuidados para Prolongación de la Vida
, Modelos Logísticos
, Masculino
, Persona de Mediana Edad
RESUMEN
The phylogenetic relationships of Trypanosoma cruzi strains were inferred using maximum-likelihood from complete 18S rDNA sequences and D7-24Salpha rDNA regions from 20 representative strains of T. cruzi. For this we sequenced the 18S rDNA of 14 strains and the D7-24Salpha rDNA of four strains and aligned them to previously published sequences. Phylogenies inferred from these data sets identified four groups, named Riboclades 1, 2, 3, and 4, and a basal dichotomy that separated Riboclade 1 from Riboclades 2, 3, and 4. Substitution models and other parameters were optimized by hierarchical likelihood tests, and our analysis of the 18S rDNA molecular clock by the likelihood ratio test suggests that a taxa subset encompassing all 2,150 positions in the alignment supports rate constancy among lineages. The present analysis supports the notion that divergence dates of T. cruzi Riboclades can be estimated from 18S rDNA sequences and therefore, we present alternative evolutionary scenarios based on two different views of T. cruzi intraspecific divergence. The first assumes a faster evolutionary rate, which suggests that the divergence between T. cruzi I and II and the extant strains occurred in the Tertiary period (37-18 MYA). The other, which supports the hypothesis that the divergence between T. cruzi I and II occurred in the Cretaceous period (144-65 MYA) and the divergence of the extant strains occurred in the Tertiary period of the Cenozoic era (65-1.8 MYA), is consistent with our previously proposed hypothesis of divergence by geographical isolation and mammalian host coevolution.
Asunto(s)
Evolución Biológica , ADN Ribosómico/genética , Genes de ARNr , Trypanosoma cruzi/genética , Animales , Funciones de Verosimilitud , Filogenia , Trypanosoma cruzi/clasificaciónRESUMEN
BACKGROUND: Pneumothorax (PNX) is a recognized cause of preventable deaths in trauma patients. Our objective was to determine the incidence of traumatic PNX, the characteristics of its victims, and the treatment they receive. METHODS: The study consisted of data set of a population-based study on major trauma. RESULTS: The incidence of PNX was 81 per 1 million population per year, mostly caused by transport accidents. PNX victims generally had multiple injuries, and they showed on-scene clinical parameters worse than victims of other chest injuries of comparable severity. Fifty-three percent of PNXs were drained during the prehospital and early (< 2 hours) hospital course. There was no uniformity of treatment among different types of rescue facilities, some of them never performing decompression despite clinical need. The z statistic for mortality was -0.63. CONCLUSION: PNX can be expected in one in five major trauma victims found alive. PNX is associated with a peculiar on-scene instability. Early decompression is often required. The effects of wider access to prehospital decompression and the reasons for its uneven availability in our setting need elucidation. Nevertheless, the present mortality follows the international standards.
Asunto(s)
Servicios Médicos de Urgencia/normas , Neumotórax/epidemiología , Calidad de la Atención de Salud , Traumatismos Torácicos/complicaciones , Análisis de Varianza , Drenaje/métodos , Humanos , Incidencia , Italia/epidemiología , Neumotórax/etiología , Neumotórax/mortalidad , Neumotórax/cirugía , Estudios Retrospectivos , Riesgo , Estadísticas no Paramétricas , Factores de TiempoRESUMEN
Three cruises, one in each of the main stream patterns in the area, were made on the central Mexican Pacific continental slope (May-June 1995, November 1995, and March 1996). Seven trawl sampling sites were defined per cruise, and in each site four bathymetric levels were sampled (20, 40, 60, and 80 m). During the warmest seasons, the highest abundance of Porichthys margaritatus was at 60 m. When the temperature of the bottom water was lower, in March 1996, the highest abundance of P. margaritatus moved towards 40 m. The depths with greatest abundance fluctuated between 18 and 21 degrees C, indicating a narrow temperature preference range. A Gaussian model was used to explain the relation between abundance and temperature.
Asunto(s)
Batrachoidiformes/fisiología , Análisis de Varianza , Animales , México , Distribución Normal , Densidad de Población , TemperaturaRESUMEN
We tested whether comparative sequence analysis of the mitochondrion-encoded cytochrome c oxidase subunit 2 gene (COX2) could be used to distinguish intraspecific variants of Candida glabrata. Mitochondrial genes are suitable for investigation of close phylogenetic relationships because they evolve much faster than nuclear genes, which in general exhibit very limited intraspecific variation. For this survey we used 11 clinical isolates of C. glabrata from three different geographical locations in Brazil, 10 isolates from one location in the United States, 1 American Type Culture Collection strain as an internal control, and the published sequence of strain CBS 138. The complete coding region of COX2 was amplified from total cellular DNA, and both strands were sequenced twice for each strain. These sequences were aligned with published sequences from other fungi, and the numbers of substitutions and phylogenetic relationships were determined. Typing of these strains was done by using 17 substitutions, with 8 being nonsynonymous and 9 being synonymous. Also, cDNAs made from purified mitochondrial polyadenylated RNA were sequenced to confirm that our sequences correspond to the expressed copies and not nuclear pseudogenes and that a frameshift mutation exists in the 3' end of the coding region (position 673) relative to the Saccharomyces cerevisiae sequence and the previously published C. glabrata sequence. We estimated the average evolutionary rate of COX2 to be 11.4% sequence divergence/10(8) years and that phylogenetic relationships of yeasts based on these sequences are consistent with rRNA sequence data. Our analysis of COX2 sequences enables typing of C. glabrata strains based on 13 haplotypes and suggests that positions 51 and 519 indicate a geographical polymorphism that discriminates strains isolated in the United States and strains isolated in Brazil. This provides for the first time a means of typing of Candida strains that cause infections by use of direct sequence comparisons and the associated divergence estimates.
Asunto(s)
Proteínas Bacterianas , Candida/clasificación , Candidiasis/microbiología , Citotoxinas/genética , Complejo IV de Transporte de Electrones/genética , Genes Bacterianos , Polimorfismo Genético , Bacteriocinas , Secuencia de Bases , Brasil , Candida/enzimología , Candida/genética , Candidiasis/epidemiología , Análisis por Conglomerados , Cartilla de ADN , Geografía , Mitocondrias/enzimología , Mitocondrias/genética , Epidemiología Molecular , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie , Estados UnidosRESUMEN
Reactive oxygen intermediates (ROI) and cytokines, particularly tumor necrosis factor (TNF) have been implicated in the pathogenesis of influenza. Using a murine model of influenza, we have studied the levels of TNF, interleukin 6 (IL-6) and of superoxide-generating xanthine oxidase (XO). Mice infected intranasally with influenza virus APR/8 had high levels of XO, TNF and IL-6 in the broncoalveolar lavage, as early as 3 d after infection. XO was elevated also in serum and lung tissue. Administration of the antioxidant N-acetylcysteine (NAC,1 g/kg per day, orally) significantly decreased the mortality in infected mice, indicating a role for RO1 in the lethality associated with influenza infection.
RESUMEN
Although sclerophylly is widespread through the world and is often the dominant leaf-form in mediterranean climates, the mechanical properties of sclerophyllous leaves are poorly understood. The term "sclerophyllous" means hard-leaved, but biologists also use terms such as tough, stiff and leathery to describe sclerophyllous leaves. The latter term has no precise definition that allows quantification. However, each of the former terms is well-defined in materials engineering, although they may be difficult or sometimes inappropriate to measure in leaves because of their size, shape or composite and anisotropic nature. Two of the most appropriate and practically applicable mechanical properties of sclerophyllous leaves are "strength" and "toughness", which in this study were applied using punching, tearing and shearing tests to 19 species of tree and shrub at Wilson's Promontory, Australia. The results of these tests were compared with leaf specific mass (LSM) and a sclerophylly index derived from botanists' ranks. Principal components analysis was used to reduce the set of mechanical properties to major axes of variation. Component 1 correlated strongly with the botanists' ranks. Overall, leaves ranked as sclerophyllous by botanists were both tough and strong in terms of punching and tearing tests. In addition, tough and strong leaves typically had high toughness and strength per unit leaf thickness. There was also a significant correlation between component 1 and LSM. Although more detailed surveys are required, we argue that sclerophylly should be defined in terms of properties that have precise meanings and are measurable, such as toughness and strength, and that relate directly to mechanical properties as implicit in the term.
RESUMEN
A better understanding of trauma epidemiology may allow to enhance the organisation of trauma systems with a potentially relevant impact on the level of trauma care. A one year epidemiology study (1st March 1998-28th February 1999) was planned in Friuli Venezia Giulia with the aim to collect all prehospital, hospital and outcome data of patients who sustained a major trauma (ISS > 15) within the regional border. In 12 months 15,429 traumatized patients (14,108 residents) were admitted to any one of the Regional hospitals. Over 1% of the whole population sustained injuries severe enough to cause hospital admission. 630 people (77.3% male, 27.7% female average age 42 ys) had a major trauma. The incidence of major trauma is 525 per million people per year. RTA was by far the most important cause of major injuries (78.6%) followed by work accidents (6.8%), domestic (5.9%) and sport accidents (1.9%). Only 1.2% of all the major injuries was the consequence of interpersonal violence. One hundred-sixty-six trauma victims died on the spot (149) or before hospital arrival (17). 464 patients with major injuries reached the hospital alive. More than two third of the patients with ISS > 15, suffered from a multiple trauma. 70% had a severe injury to the head (AIS > or = 3). Head trauma occurred as an isolated injury in only 35.3%. Hospital mortality within 30 days from admission (trauma death) was 25.1%. The results of the follow-up at 6 months are still incomplete. However the preliminary data clearly show that a high percentage of the patients who were discharged alive from the ICU had a good neurologic recovery.