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1.
Arq. bras. med. vet. zootec. (Online) ; 70(4): 1045-1052, jul.-ago. 2018. tab, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-916320

RESUMEN

Eyes from brachycephalic dogs were studied by acoustic radiation force impulse (ARFI) elastography to establish quantitative and qualitative reference values related to the shape and rigidity of some ocular structures. Eighty-four eyes from 42 adult brachycephalic dogs were included in this study. Animals were subjected to physical, laboratory, and ophthalmic examinations. Following confirmation of good health, the dogs were subjected to ultrasonography and ARFI elastography, emphasizing the optic nerve, ciliary body, and lens. On qualitative elastography, homogeneous characteristics were observed on the ciliary body and optic nerve. Aqueous and vitreous humors were visualized as mosaic-like images. Quantitative elastography showed the mean optic nerve shear wave velocity (SWV) was 1.01±0.27m/s, temporal ciliary body was 0.91±0.24m/s, and nasal ciliary body was 0.91±0.3m/s. The SWV of the lens values were out of range, this value was not detectable by this software. Elastography has proved to be a non-invasive procedure and feasible in dogs. The establishmentof the parameters of degree of rigidity of ocular structures will serve as a baseline for animals with eye disorders. Results may be extrapolated to primary research on the applicability of ARFI in the evaluation of ocular bulb in humans.(AU)


Estruturas oculares de cães braquicéfalos foram estudadas por elastografia acoustic radiation force impulse (ARFI) para estabelecer valores quantitativos e qualitativos de referência relacionados com a forma e a rigidez de algumas estruturas oculares. Foram avaliados 84 olhos de 42 cães braquicéfalos neste estudo. Os animais foram submetidos aos exames físico, laboratorial e aos exames oftalmológicos. Após a confirmação da sanidade dos pacientes, os cães foram submetidos à ultrassonografia e à elastografia ARFI, enfatizando-se o nervo óptico, o corpo ciliar e a lente. Para elastografia qualitativa, foram observadas características homogêneas no corpo ciliar e no nervo óptico. Os humores aquoso e vítreo foram visibilizados como imagens tipo mosaico. A elastografia quantitativa demonstrou velocidades de cisalhamento para nervo óptico de 1,01±0,27m/s, para corpo ciliar temporal de 0,91±0,24m/s e para corpo ciliar nasal de 0,91±0,3m/s. Valores dessas velocidades para lentes apresentaram-se fora do intervalo: X.XXm/s. A elastografia provou ser um procedimento não invasivo e viável para cães. Estabelecidos os parâmetros do grau de rigidez das estruturas oculares, futuramente tais dados servirão como padrão para avaliação de animais com os distúrbios oculares. Os resultados podem ser extrapolados para a pesquisa primária sobre a aplicabilidade da ARFI na avaliação do bulbo ocular em seres humanos.(AU)


Asunto(s)
Animales , Perros , Diagnóstico por Imagen de Elasticidad/estadística & datos numéricos , Diagnóstico por Imagen de Elasticidad/veterinaria , Anomalías del Ojo/diagnóstico por imagen , Perros/anomalías
3.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);67(1): 94-102, 2/2015. tab
Artículo en Portugués | LILACS | ID: lil-741121

RESUMEN

Neste estudo, 67 ejaculados foram avaliados, antes e depois da técnica de swim-up, em relação à qualidade seminal e à presença do CAEV. Das 67 amostras testadas por PCRn, antes do swim-up, 47 (70,15%) foram positivas para o DNA pró-viral. No entanto, quatro amostras adicionais foram positivas ao RT-nested PCR após o swim-up, o que permite dizer que, pelo menos, 76,12% (51/67) delas estavam infectadas antes da lavagem. Todavia, em 23,88% (16/67) das amostras não foi detectada a presença do CAEV. Após a aplicação da técnica de swim-up, constatou-se, pela PCRn e RT-nested PCR, que houve uma redução significativa (χ²= 9,078; p<0,001) da presença do CAEV nas amostras seminais, pois 28 de 51 amostras positivas resultaram livres do vírus (54,90%), tanto para DNA pró-viral quanto para o vírus livre. Em relação à motilidade individual progressiva (MIP) e vigor espermático obtidos antes e depois da técnica de swim-up, observou-se uma diminuição significativa em suas médias, sendo o MIP de 86,42% para 71,49%, já o vigor espermático de 4,16 para 3,93. Conclui-se que a eliminação do CAEV no sêmen é de caráter intermitente, e que a associação da PCRn e RT-nested PCR é uma opção segura para a certificação sanitária individual das amostras seminais quanto à presença ou ausência do CAEV. Finalmente, a técnica de swim-up promove uma redução na infectividade de amostras de sêmen contaminadas, e, além disso, é possível promover a recuperação de espermatozoides viáveis.


In this study, 67 ejaculates were assessed before and after the swim-up technique in relation to semen quality and presence of CAEV. Of the 67 samples tested by Nested PCR, before swim-up 47 (70.15%) were positive for viral DNA. Furthermore, four additional samples were positive for RT-nested PCR after swim-up, which allows us to affirm that at least 76.12% (51/67) were infected before washing. However, 23.88% (16/67) of the samples did not detect the presence of CAEV. After application of the swim-up technique it was found, by Nested PCR and RT-nested PCR, that there was a significant decrease (χ² = 9.078, p <0.001) in the presence of CAEV in semen samples, once 28 of 51 positive samples were free from the virus (54.90%) for both proviral DNA and the free form of the virus. Regarding individual progressive motility (IPM) and spermatic vigor obtained before and after the swim-up technique, a significant decrease was observed in the average, being 86.42% of the IPM to 71.49% and the spermatic vigor from 4.16 for the 3.93. It is concluded that the removal of CAEV in semen has an intermittent character, and the combination of PCR and RT-nested PCR is a safe option for health certification of individual semen samples for the presence or absence of CAEV. Finally, the swim-up technique promotes a reduction in the infectivity of contaminated semen samples, and it is possible to promote the recovery of high individual progressive motility sperm and sperm vigor.


Asunto(s)
Animales , Masculino , Reacción en Cadena de la Polimerasa/estadística & datos numéricos , Reacción en Cadena de la Polimerasa/veterinaria , Virus de la Artritis-Encefalitis Caprina/aislamiento & purificación , Análisis de Semen/veterinaria
4.
World J Microbiol Biotechnol ; 31(2): 399-406, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25549906

RESUMEN

Prodigiosin is an alkaloid and natural red pigment produced by Serratia marcescens. Prodigiosin has antimicrobial, antimalarial and antitumor properties and induces apoptosis in T and B lymphocytes. These properties have piqued the interest of researchers in the fields of medicine, pharmaceutics and different industries. The aim of the present study was to evaluate the antimicrobial activity of prodigiosin against pathogenic micro-organisms. The red pigments produced by S. marcescens exhibited absorption at 534 nm, Rf of 0.59 and molecular weight of 323 m/z. Antimicrobial activity was tested against oxacillin-resistant Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Streptococcus pyogenes, Acinetobacter sp. and oxacillin-resistant S. aureus. The standard antibiotics employed were ampicillin, chloramphenicol, gentamicin and oxacillin. The disc-diffusion tests demonstrated significant inhibition zones for S. aureus (35 ± 0.6), E. faecalis (22 ± 1.0) and S. pyogenes (14 ± 0.6). However, prodigiosin showed resistance to E. coli, P. aeruginosa and acinetobacter, where no significant formation of inhibitory halos were observed. We determined the inhibitory minimum concentrations and bactericidal for 20 strains of oxacillin-resistant S. aureus (ORSA). The pattern was the antibiotic oxacillin. The minimum inhibitory concentrations observed ranged from 1, 2 and 4.0 µg/mL, respectively, while the minimum bactericidal concentrations ranged from 2, 4, 8 and 16 µg/mL. The S. marcescens prodigiosin produced by showed bactericidal and bacteriostatic effect showing promising antimicrobial activity and suggesting future studies regarding its applicability in antibiotics therapies directed ORSA.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Prodigiosina/farmacología , Serratia marcescens/química , Acinetobacter/efectos de los fármacos , Antibacterianos/química , Bacterias/crecimiento & desarrollo , Pruebas Antimicrobianas de Difusión por Disco , Enterococcus faecalis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Prodigiosina/química , Pseudomonas aeruginosa/efectos de los fármacos , Espectrofotometría , Staphylococcus aureus/efectos de los fármacos , Streptococcus pyogenes/efectos de los fármacos
5.
Arq. bras. med. vet. zootec. (Online) ; 67(1): 1024-102, 2015. tab
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1462523

RESUMEN

Neste estudo, 67 ejaculados foram avaliados, antes e depois da técnica de swim-up, em relação à qualidade seminal e à presença do CAEV. Das 67 amostras testadas por PCRn, antes do swim-up, 47 (70,15%) foram positivas para o DNA pró-viral. No entanto, quatro amostras adicionais foram positivas ao RT-nested PCR após o swim-up, o que permite dizer que, pelo menos, 76,12% (51/67) delas estavam infectadas antes da lavagem. Todavia, em 23,88% (16/67) das amostras não foi detectada a presença do CAEV. Após a aplicação da técnica de swim-up, constatou-se, pela PCRn e RT-nested PCR, que houve uma redução significativa (²= 9,078, p<0,001) da presença do CAEV nas amostras seminais, pois 28 de 51 amostras positivas resultaram livres do vírus (54,90%), tanto para DNA pró-viral quanto para o vírus livre. Em relação à motilidade individual progressiva (MIP) e vigor espermático obtidos antes e depois da técnica de swim-up, observou-se uma diminuição significativa em suas médias, sendo o MIP de 86,42% para 71,49%, já o vigor espermático de 4,16 para 3,93. Conclui-se que a eliminação do CAEV no sêmen é de caráter intermitente, e que a associação da PCRn e RT-nested PCR é uma opção segura para a certificação sanitária individual das amostras seminais quanto à presença ou ausência do CAEV. Finalmente, a técnica de swim-up promove uma redução na infectividade de amostras de sêmen contaminadas, e, além disso, é possível promover a recuperação de espermatozoides viáveis.


In this study, 67 ejaculates were assessed before and after the swim-up technique in relation to semen quality and presence of CAEV. Of the 67 samples tested by Nested PCR, before swim-up 47 (70.15%) were positive for viral DNA. Furthermore, four additional samples were positive for RT-nested PCR after swim-up, which allows us to affirm that at least 76.12% (51/67) were infected before washing. However, 23.88% (16/67) of the samples did not detect the presence of CAEV. After application of the swim-up technique it was found, by Nested PCR and RT-nested PCR, that there was a significant decrease (² = 9.078, p <0.001) in the presence of CAEV in semen samples, once 28 of 51 positive samples were free from the virus (54.90%) for both proviral DNA and the free form of the virus. Regarding individual progressive motility (IPM) and spermatic vigor obtained before and after the swim-up technique, a significant decrease was observed in the average, being 86.42% of the IPM to 71.49% and the spermatic vigor from 4.16 for the 3.93. It is concluded that the removal of CAEV in semen has an intermittent character, and the combination of PCR and RT-nested PCR is a safe option for health certification of individual semen samples for the presence or absence of CAEV. Finally, the swim-up technique promotes a reduction in the infectivity of contaminated semen samples, and it is possible to promote the recovery of high individual progressive motility sperm and sperm vigor.


Asunto(s)
Masculino , Animales , Análisis de Semen/veterinaria , Reacción en Cadena de la Polimerasa , Reacción en Cadena de la Polimerasa/veterinaria , Virus de la Artritis-Encefalitis Caprina/aislamiento & purificación
6.
Differentiation ; 84(5): 355-65, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23142731

RESUMEN

Cellular systems implanted into an injured nerve may produce growth factors or extracellular matrix molecules, modulate the inflammatory process and eventually improve nerve regeneration. In the present study, we evaluated the therapeutic value of human umbilical cord matrix MSCs (HMSCs) on rat sciatic nerve after axonotmesis injury associated to Vivosorb® membrane. During HMSCs expansion and differentiation in neuroglial-like cells, the culture medium was collected at 48, 72 and 96 h for nuclear magnetic resonance (NMR) analysis in order to evaluate the metabolic profile. To correlate the HMSCs ability to differentiate and survival capacity in the presence of the Vivosorb® membrane, the [Ca(2+)]i of undifferentiated HMSCs or neuroglial-differentiated HMSCs was determined by the epifluorescence technique using the Fura-2AM probe. The Vivosorb® membrane proved to be adequate and used as scaffold associated with undifferentiated HMSCs or neuroglial-differentiated HMSCs. In vivo testing was carried out in adult rats where a sciatic nerve axonotmesis injury was treated with undifferentiated HMSCs or neuroglial differentiated HMSCs with or without the Vivosorb® membrane. Motor and sensory functional recovery was evaluated throughout a healing period of 12 weeks using sciatic functional index (SFI), extensor postural thrust (EPT), and withdrawal reflex latency (WRL). Stereological analysis was carried out on regenerated nerve fibers. In vitro investigation showed the formation of typical neuroglial cells after differentiation, which were positively stained for the typical specific neuroglial markers such as the GFAP, the GAP-43 and NeuN. NMR showed clear evidence that HMSCs expansion is glycolysis-dependent but their differentiation requires the switch of the metabolic profile to oxidative metabolism. In vivo studies showed enhanced recovery of motor and sensory function in animals treated with transplanted undifferentiated and differentiated HMSCs that was accompanied by an increase in myelin sheath. Taken together, HMSC from the umbilical cord Wharton jelly might be useful for improving the clinical outcome after peripheral nerve lesion.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Regeneración Nerviosa , Poliésteres/uso terapéutico , Animales , Antígenos Nucleares/análisis , Diferenciación Celular , Línea Celular , Proteína GAP-43/análisis , Proteína Ácida Fibrilar de la Glía/análisis , Glucólisis , Humanos , Espectroscopía de Resonancia Magnética , Membranas Artificiales , Células Madre Mesenquimatosas/citología , Actividad Motora , Vaina de Mielina/metabolismo , Compresión Nerviosa , Proteínas del Tejido Nervioso/análisis , Neuroglía/citología , Traumatismos de los Nervios Periféricos/terapia , Ratas , Nervio Ciático/química , Nervio Ciático/fisiología , Nervio Ciático/cirugía , Sensación , Gelatina de Wharton/citología
7.
Neurol Res ; 34(10): 971-6, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23146299

RESUMEN

OBJECTIVES: Brain tissue oxygen concentration (PbtO(2)) monitoring has been used in aneurysm surgery to detect decreased brain oxygenation during temporary clipping. The effects of circulatory interruption according to different aneurysm locations have not been established. In this work, variations in PbtO(2) during temporary clipping were studied in anterior communicating (AcomA), posterior communicating (PcomA) origin, and middle cerebral artery (MCA) aneurysm surgery. METHODS: PbtO(2) was monitored during surgery of 41 patients; aneurysms were located in the AcomA (10 cases), origin of PcomA (8 cases), and MCA bifurcation (23 cases). Temporary clips were used in all cases. Variations in PbtO(2) values obtained during application of temporary clips were evaluated and studied according to the duration and type of circulatory interruption for each aneurysm location. RESULTS: In AcomA aneurysm surgery, a significant decrease in PbtO(2) values was found in 31% of the periods of temporary clipping, whereas in PcomA and MCA aneurysm surgery, significant decreases were found in all temporary clip applications (100%). In MCA aneurysms, the amplitude of decrease in PbtO(2) was higher when the circulatory interruption lasted for 2 or more minutes, compared with shorter periods of temporary clipping. DISCUSSION: During temporary clipping, different variations in PbtO(2) values were obtained when comparing frontal and temporal regions of monitoring: in MCA and PcomA origin aneurysms, significant variations were registered in all periods of temporary regional circulatory interruption, but the same results were not found in frontal monitoring for AcomA aneurysm surgery.


Asunto(s)
Encéfalo/metabolismo , Encéfalo/cirugía , Aneurisma Intracraneal/metabolismo , Aneurisma Intracraneal/cirugía , Monitoreo Intraoperatorio/métodos , Oxígeno/metabolismo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Instrumentos Quirúrgicos , Factores de Tiempo , Adulto Joven
8.
Neurol Res ; 34(2): 181-6, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22333942

RESUMEN

BACKGROUND: Vasospasm is a frequent complication of subarachnoid hemorrhage (SAH), implicated in poor outcome, and prediction of its occurrence might be important on the therapeutic approach of this condition. Brain oxygenation in aneurysmal SAH was prospectively monitored during surgery in 28 patients, using brain tissue oxygen pressure (PbtO(2)), studying its association with the occurrence of post-operative vasospasm, detected by transcranial Doppler. METHODS: PbtO(2) monitoring was performed during surgery of 28 patients with aneurysmal SAH, using a polarographic microcatheter (Licox; GMS, Kiel, Germany), inserted into the cerebral tissue. The aneurysms were localized in the anterior communicating artery (AcoA) complex (eight cases), in the posterior communicating artery (Pcom) origin (seven cases), and in the middle cerebral artery (MCA) bifurcation (13 cases). Basal PbtO(2) values, obtained immediately before application of temporary or definitive clips, were studied according to age, clinical status and CT findings. The association between the basal values and the occurrence of increased blood flow velocity in the post-operative transcranial Doppler (TCD vasospasm) was investigated. RESULTS: Post-operative TCD vasospasm developed in 13 patients, all of them with basal values inferior to 10 mmHg. PbtO(2) basal value was significantly lower in cases that developed TCD vasospasm. This association was independent of age, clinical status, or CT findings. CONCLUSION: The finding of low intraoperative basal PbtO(2) values may be an indicator for a high risk of occurrence of post-operative TCD vasospasm in cases of aneurysmatic SAH.


Asunto(s)
Encéfalo/irrigación sanguínea , Monitoreo Intraoperatorio/métodos , Hemorragia Subaracnoidea/complicaciones , Vasoespasmo Intracraneal/etiología , Catéteres , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio/instrumentación , Hemorragia Subaracnoidea/cirugía , Ultrasonografía Doppler Transcraneal
9.
Surg Neurol Int ; 2: 37, 2011 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-21541203

RESUMEN

INTRODUCTION: The management of incidental unruptured aneurysms remains a matter of controversy; middle-sized or large anterior circulation incidental aneurysms, in young or middle age patients, should be considered for treatment. Surgical clipping is an accepted treatment for middle cerebral artery unruptured aneurysms. Ischemic events can occur even in cases of incidental aneurysm surgery. Since regional cerebral blood flow can be compromised due to temporary arterial clipping or to incorrect placement of defi nitive clip, we performed intra-operative monitoring of brain tissue oxygen concentration (PtiO(2)), to detect changes in brain oxygenation due to reduced blood fl ow, eventually leading to ischemia, during surgery of middle cerebral artery incidental aneurysms. METHODS: PtiO(2) monitoring was performed during surgery of eight patients harboring incidental MCA aneurysms, using a polarographic microcatheter (Licox, GMS - Kiel, Germany), placed in the temporal lobe on the side of the lesion, from dural opening to dural closure. RESULTS: Basal values varied between 2.3 and 27.3 mmHg; these values are lower than those previously described in the literature as "normal" for uninjured brain or in cases of subarachnoid hemorrhage. In all patients, a significant decrease in PtiO2 was found in every period of temporary clipping of MCA. Post-operative infarction in the territory of middle cerebral artery occurred in one patient and, in that case, there was a persistent minimum value of 0.6 mmHg, without recovery after the placement of the definitive clip. In another patient, an incorrect placement of the definitive clip could be predicted by a decrease in PtiO(2) value. CONCLUSIONS: PtiO(2) monitoring during aneurysm surgery shows brain tissue perfusion in real time and there is a correlation between any episode of reduced blood flow to the affected vascular territory during surgery and a decrease of PtiO2 values. Unexpected low basal values were obtained in "uninjured" brain, with no influence from subarachnoid hemorrhage. The values of risk for brain infarction during temporary arterial occlusion still need further studies, but an incomplete recovery or a persistent fall in PtiO(2) values after definitive clipping should be considered as an indication for verification of the position of the clip.

10.
Biomaterials ; 29(33): 4409-19, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18723219

RESUMEN

Many studies have been dedicated to the development of scaffolds for improving post-traumatic nerve regeneration. The goal of this study was to develop and test hybrid chitosan membranes to use in peripheral nerve reconstruction, either alone or enriched with N1E-115 neural cells. Hybrid chitosan membranes were tested in vitro, to assess their ability in supporting N1E-115 cell survival and differentiation, and in vivo to assess biocompatibility as well as to evaluate their effects on nerve fiber regeneration and functional recovery after a standardized rat sciatic nerve crush injury. Functional recovery was evaluated using the sciatic functional index (SFI), the static sciatic index (SSI), the extensor postural thrust (EPT), the withdrawal reflex latency (WRL) and ankle kinematics. Nerve fiber regeneration was assessed by quantitative stereological analysis and electron microscopy. All chitosan membranes showed good biocompatibility and proved to be a suitable substrate for plating the N1E-115 cellular system. By contrast, in vivo nerve regeneration assessment after crush injury showed that the freeze-dried chitosan type III, without N1E-115 cell addition, was the only type of membrane that significantly improved posttraumatic axonal regrowth and functional recovery. It can be thus suggested that local enwrapping with this type of chitosan membrane may represent an effective approach for the improvement of the clinical outcome in patients receiving peripheral nerve surgery.


Asunto(s)
Axones/patología , Quitosano/farmacología , Modelos Animales , Regeneración Nerviosa/efectos de los fármacos , Nervio Ciático/fisiología , Animales , Axones/fisiología , Materiales Biocompatibles/farmacología , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Células Clonales , Membranas Artificiales , Ratones , Microscopía Electrónica de Rastreo , Compresión Nerviosa , Regeneración Nerviosa/fisiología , Neuroblastoma/patología , Ratas , Ratas Wistar , Recuperación de la Función/fisiología , Nervio Ciático/lesiones , Nervio Ciático/patología , Nervio Ciático/ultraestructura
11.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);59(3): 711-718, jun. 2007. tab
Artículo en Portugués | LILACS | ID: lil-461150

RESUMEN

Comparou-se o valor energético do capim-elefante, obtido em diferentes idades de rebrota, com aqueles estimados pelas equações do National Research Council (NRC) e avaliou-se o tempo de incubação da fibra em detergente neutro (FDN) que representa a digestibilidade in vivo. A avaliação do capim ocorreu nas idades de 33, 48, 63, 78 e 93 dias de rebrota, utilizando-se quatro bovinos castrados, com peso médio inicial de 320kg. O procedimento de validação dos parâmetros foi realizado por meio do ajuste do modelo de regressão linear simples dos valores estimados sobre os observados. Realizou-se um ensaio de degradação in situ utilizando-se os tempos de 6, 12, 24, 36, 48, 72, 96, 120 e 144 horas para a determinação da degradabilidade da matéria seca (MS) e da fibra em detergente neutro (FDN). As frações digestíveis da FDN, a proteína bruta (PB), o extrato etéreo (EE) e os valores de NDT foram subestimados pelas equações do NRC, enquanto as dos carboidratos não fibrosos (CNF) foram semelhantes aos valores observados. O tempo de incubação in situ que melhor representou a digestibilidade in vivo da FDN foi o de 72 horas. Concluiu-se que as equações do NRC não foram eficientes na estimativa do valor energético do capim-elefante. Sugere-se a incubação in situ durante 72 horas para determinação da fração digestível da FDN.


This work was carried out to compare the energy (TDN) value of elephantgrass harvest at different regrowth ages with those estimated by NRC equations and evaluate neutral detergent fiber (NDF) incubation time, that represents in vivo digestibility. Four steers with average initial weight of 320kg were fed elephantgrass harvested at 33, 48, 63, 78 and 93 regrowth ages. Energy value of elephantgrass at different ages was calculated by using chromic oxide to obtain fecal dry matter production, and NDT values were estimated by NRC equations. Parameter validation method was obtained by fitting the simple linear regression model on the observed values. An in situ degradation trial, by using incubation times of 6 ,12, 24, 36, 48, 72, 96, 120 and 144 hours, was performed to determine dry matter (DM) and neutral detergent fiber (NDF) degradability. NDF, crude protein (CP) and ether extract (EE) digestible fractions and NDT values were underestimated by NRC equations, and nonfiber carbohydrates (NFC) values were similar to the observed ones. The best correlation between in situ incubation time and in vivo NDF digestibility was at 72 hours. NRC equations were not efficient to estimate elephantgrass energy value. It is suggested the in situ incubation for 72 hours to determine NDF digestible fraction of elephantgrass.


Asunto(s)
Animales , Bovinos , Valor Nutritivo , Pennisetum , Rumen , Alimentación Animal
12.
Int J Pediatr Otorhinolaryngol ; 71(7): 1047-54, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17467064

RESUMEN

OBJECTIVE: This study examined the risk factors associated with middle ear disease in a cohort of Pacific 2-year-old children residing in New Zealand. METHODS: The data were gathered as part of the Pacific Island Families: first 2 years of life (PIF) study in which 656 2-year-old were screened using tympanometry to identify children at risk for otitis media with effusion (OME) and other otological disorders. RESULTS: Within this 2-year-old cohort of Pacific children, one set of factors significantly associated with OME was clustered around the respiratory and auditory health of the child over the past year. OME was more likely for children who were regularly suffering from fluid/pus discharge from ears (OR=2.10, 95% CI: 1.01-4.35), children with five or more coughs/colds in the last year (OR=1.90, 95% CI: 1.22-3.00), and children who frequently/constantly snored (OR=2.60, 95% CI: 1.09-6.23) to have OME. Those children who were treated at home for breathing problems were more that two times more likely to have OME (OR=2.61, 95% CI: 1.55-4.42). A second set of factors was clustered around environmental risks that exposed children to a large number of other children. Children who attended a day care centre for more than 20h were five times more likely (OR=5.21, 95% CI: 2.90-9.35) and those who regularly attended church (OR=2.78, 95% CI: 1.05-7.40) were almost three times more likely to have OME. CONCLUSIONS: These findings portray a child compromised by persistent ear infections and general coughs and colds as being at increased risk of contracting OME. In line with international research these findings raise questions about the negative child health effects associated with the day care environment for young children.


Asunto(s)
Otitis Media/epidemiología , Pruebas de Impedancia Acústica , Preescolar , Estudios de Cohortes , Familia , Femenino , Humanos , Lactante , Entrevistas como Asunto , Masculino , Tamizaje Masivo , Nueva Zelanda/epidemiología , Otitis Media/etiología , Islas del Pacífico/epidemiología , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios
13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 74(2 Pt 1): 021920, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17025485

RESUMEN

The Davydov-Scott model describes the transfer of energy along hydrogen-bonded chains, like those that stabilize the structure of alpha helices. It is based on the hypothesis that amide I excitations are created (by the hydrolysis of ATP, for instance) and kept in the system. Recent experimental results confirm that the energy associated with amide I excitations does indeed last for tens of picoseconds in proteins and model systems. However, the Davydov-Scott model cannot describe the conversion of that energy into work, because it conserves the number of excitations. With the aim of describing conformational changes, we consider, in this paper, a nonconserving generalization of the model, which is found to describe essentially a contraction of the hydrogen bond adjacent to the site where an excitation is present. Unlike the one-site Davydov-Scott model, that contraction is time dependent because the number of excitations is not conserved. However, considering the time average of the dynamical variables, the results reported here tend to the known results of the Davydov-Scott model.


Asunto(s)
Adenosina Trifosfato/química , Amidas/química , Transferencia de Energía , Modelos Químicos , Modelos Moleculares , Simulación por Computador , Termodinámica
14.
Int J Pediatr Otorhinolaryngol ; 70(10): 1771-8, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16828885

RESUMEN

OBJECTIVE: The aim of this study was to determine the prevalence of chronic middle ear disease in 2-year-old Pacific children living in New Zealand. METHODS: The data were gathered as part of the Pacific Islands Families: First Two Years of Life (PIF) Study in which 1001 two year olds were screened using tympanometry to identify children at risk for otitis media with effusion (OME) and other otological disorders. Those failing the screening tests were referred to Manukau Superclinic where they had a further tympanometry test, and if they failed this test, were followed up with a comprehensive otological examination by an otolaryngologist using otomicroscopy and pneumatic otoscopy. RESULTS: Bilateral otitis media with effusion (OME) was the most common abnormality detected (N=102) with further cases of unilateral OME (N=8), and unilateral OME resolving (N=2). Other cases of OME were associated with acute otitis media (AOM), impacted wax (N=1), perforation (N=1), and mild retraction (N=2). Overall there were 118 children with unilateral or bilateral OME. AOM of any form was seen in nine cases. Retraction of the tympanic membrane was seen in 26 cases. The population prevalence among Pacific 2-year-old children was estimated as 25.4% for OME, 1.9% for AOM, and 26.9% for OME or AOM. CONCLUSIONS: These findings reveal that over 25% of Pacific Island 2-year-old were affected by OME and recommend the consideration of national screening for OME and other otological disorders at this earlier age.


Asunto(s)
Nativos de Hawái y Otras Islas del Pacífico , Otitis Media con Derrame/diagnóstico , Otitis Media con Derrame/epidemiología , Pruebas de Impedancia Acústica , Preescolar , Enfermedad Crónica , Estudios de Cohortes , Femenino , Humanos , Masculino , Tamizaje Masivo , Nueva Zelanda/epidemiología , Otitis Media con Derrame/etnología , Otoscopía , Prevalencia
15.
Rev. bras. farmacogn ; 15(4): 298-303, out.-dez. 2005. tab
Artículo en Inglés | LILACS | ID: lil-570933

RESUMEN

Several species of the genus Hyptis have presented medicinal characteristics and are frequently indicated to treat gastro intestinal infections, gramps and pain, as well as for skin infections. Three harvests were carried out using six H. pectinata accessions, and the following characteristics were evaluated: plant height, canopy diameter, leave length (L) and width (W), L/W relation and dry weight of leaves and stem. The accession SAM006 have presented highest leave dry matter yield when the three harvests were summed. The aqueous leaf extracts of the same six H. pectinata accessions were tested for anti-edematogenic effect using the carrageenin-induced rat paw edema at doses of 200, 400 and 600 mg/kg. The extracts administered orally had a significant anti-edematogenic effect. The dose of 200 mg/kg of accessions SAM004 and SAM005 had a stronger effect reducing the edema by 19.6 percent and 15.4 percent, respectively. Similar results were obtained using higher dosages of the aqueous extract of the accessions SAM002, SAM003 and SAM006. It can be concluded that the accessions SAM004, SAM005 and SAM006 are promising genotypes for a plant breeding program that aims the development of a cultivar with highest leave yielding and anti-edematogenic effect.

16.
Early Hum Dev ; 60(1): 35-42, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11054582

RESUMEN

Several recent studies have reported a causal association between stature and month of birth. Perinatal exposure to sunlight has been suggested as the principal factor underlying this relationship, although the mechanisms involved remain a matter of debate. The longitudinal design of the present study allowed us to directly test the influence of perinatal sunlight exposure (and other meteorological and behavioural factors) on body size at birth and at regular intervals up to age 26. The findings confirmed that pre-natal sunlight is one of the most significant determinants of height. However, the trimester of greatest influence differs depending on the age at which study members were measured.


Asunto(s)
Desarrollo Embrionario y Fetal , Crecimiento , Luz Solar , Peso al Nacer , Constitución Corporal , Estatura , Femenino , Estudios de Seguimiento , Edad Gestacional , Humanos , Recién Nacido , Estudios Longitudinales , Nueva Zelanda , Embarazo , Análisis de Regresión , Estaciones del Año , Fumar
17.
J Am Acad Child Adolesc Psychiatry ; 37(6): 594-601, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9628079

RESUMEN

OBJECTIVE: To examine the young adult physical health outcomes of adolescent girls with behavior problems. METHOD: Girls with conduct disorder, girls with depression, girls with anxiety, and healthy girls (N = 459) who had been evaluated at age 15 years were followed up at age 21, when general physical health, substance dependence, and reproductive health were assessed. RESULTS: After control for potentially confounding variables including prior health, adolescent conduct disorder predicted more medical problems, poorer self-reported overall health, lower body mass index, alcohol and/or marijuana dependence, tobacco dependence, daily smoking, more lifetime sexual partners, sexually transmitted disease, and early pregnancy. Adolescent depression predicted only adult tobacco dependence and more medical problems; adolescent anxiety predicted more medical problems. CONCLUSIONS: The robust link between female adolescent conduct disorder and poor physical health in adulthood suggests that intervention with girls who have conduct disorder may be a strategy for preventing subsequent health problems.


Asunto(s)
Ansiedad/epidemiología , Trastorno de la Conducta/epidemiología , Depresión/epidemiología , Estado de Salud , Adolescente , Adulto , Ansiedad/complicaciones , Ansiedad/psicología , Trastorno de la Conducta/complicaciones , Trastorno de la Conducta/psicología , Depresión/complicaciones , Depresión/psicología , Femenino , Humanos , Análisis de los Mínimos Cuadrados , Estudios Longitudinales , Nueva Zelanda , Embarazo , Riesgo , Conducta Sexual/psicología , Análisis de Supervivencia
18.
Addiction ; 91(11): 1705-14, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8972928

RESUMEN

A follow-up of smoking behaviour to age 18 in a longitudinal study of a birth cohort enabled an assessment of the prevalence of smoking and quitting among adolescents approaching adulthood. There was a dramatic increase in number of daily smokers (15% at age 15 years to 31% at age 18 years), and in a climate of expected decreases in smoking, a history of never smoking to age 15 years was not as protective against future smoking as anticipated. Among 15-year-olds who had experimented with smoking, only 11% per year stopped by age 18 years. Cessation rates for adolescent daily smokers were low (3% had not smoked in the last year at age 18 years), and previously have not been widely reported. We also examined some methodological issues related to self-reported prevalence rates, in particular reliability, validity and sources of bias, finding confirmation of the accuracy of information from prospective longitudinal studies and supporting the conclusion that adolescents' recall for information beyond a 1-year period is inconsistent.


Asunto(s)
Autorrevelación , Cese del Hábito de Fumar/estadística & datos numéricos , Fumar/epidemiología , Adolescente , Sesgo , Estudios de Cohortes , Estudios Transversales , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Incidencia , Masculino , Nueva Zelanda/epidemiología , Fumar/psicología , Cese del Hábito de Fumar/psicología , Prevención del Hábito de Fumar
19.
Arch Dis Child ; 75(5): 392-8, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8957951

RESUMEN

BACKGROUND: Previous studies have not resolved the importance of several potential risk factors for the development of childhood atopy, airway hyperresponsiveness, and wheezing, which would allow the rational selection of interventions to reduce morbidity from asthma. Risk factors for these disorders were examined in a birth cohort of 1037 New Zealand children. METHODS: Responses to questions on respiratory symptoms and measurements of lung function and airway responsiveness were obtained every two to three years throughout childhood and adolescence, with over 85% cohort retention at age 18 years. Atopy was determined by skin prick tests at age 13 years. Relations between parental and neonatal factors, the development of atopy, and features of asthma were determined by comparison of proportions and logistic regression. RESULTS: Male sex was a significant independent predictor for atopy, airway hyper-responsiveness, hay fever, and asthma. A positive family history, especially maternal, of asthma strongly predicted childhood atopy, airway hyperresponsiveness, asthma, and hay fever. Maternal smoking in the last trimester was correlated with the onset of childhood asthma by the age of 1 year. Birth in the winter season increased the risk of sensitisation to cats. Among those with a parental history of asthma or hay fever, birth in autumn and winter also increased the risk of sensitisation to house dust mites. The number of siblings, position in the family, socioeconomic status, and birth weight were not consistently predictive of any characteristic of asthma. CONCLUSIONS: Male sex, parental atopy, and maternal smoking during pregnancy are risk factors for asthma in young children. Children born in winter exhibit a greater prevalence of sensitisation to cats and house dust mites. These data suggest possible areas for intervention in children at risk because of parental atopy.


Asunto(s)
Asma/etiología , Hiperreactividad Bronquial/etiología , Hipersensibilidad Inmediata/etiología , Asma/genética , Orden de Nacimiento , Peso al Nacer , Hiperreactividad Bronquial/genética , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Hipersensibilidad Inmediata/genética , Masculino , Análisis Multivariante , Rinitis Alérgica Estacional/etiología , Rinitis Alérgica Estacional/genética , Factores de Riesgo , Estaciones del Año , Factores Sexuales , Contaminación por Humo de Tabaco/efectos adversos
20.
J Adolesc Health ; 16(1): 71-7, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7742343

RESUMEN

PURPOSE: Studies of adolescent smoking have concentrated on factors that are associated with smoking (vulnerability), but have tended not to examine whether these factors also describe adolescents who have been at risk of becoming smokers but have not succumbed, for example, to the social pressure of having friends who smoke (resilience). METHODS: Results from a longitudinal study were used to examine the predictors of resilience to social influence from among a selected group of factors associated with adolescent smoking. RESULTS: Among these with no recent history of smoking, the predictor variables for vulnerability and resilience were different across age. However, for adolescents who had a recent history of smoking there were no predictors of continued smoking or of stopping, apart from whether or not a friend smoked. CONCLUSIONS: Resilience factors against smoking show the characteristics of those who have successfully resisted the social influence to smoke. Identification of further predictors of resilience would help in the development of intervention programs and should include a reexamination of factors not usually correlated with smoking status.


Asunto(s)
Conducta del Adolescente , Actitud , Padres , Psicología del Adolescente , Asunción de Riesgos , Fumar/psicología , Medio Social , Adolescente , Sesgo , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Pronóstico , Análisis de Regresión , Factores de Riesgo , Fumar/epidemiología
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