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1.
Bioresour Technol ; 200: 90-102, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26476169

RESUMO

Lignocellulose fractionation is a key biorefinery process that need to be understood. In this work, a comprehensive study on hydrothermal-fractionation of holm oak in a semi-continuous system was conducted. The aim was to develop a physicochemical model in order to reproduce the role of temperature and water flow over the products composition. The experiments involved two sets: at constant flow (6mL/min) and two different ranges of temperature (140-180 and 240-280°C) and at a constant temperature range (180-260°C) and different flows: 11.0, 15.0 and 27.9mL/min. From the results, temperature has main influence and flow effect was observed only if soluble compounds were produced. The kinetic model was validated against experimental data, reproducing the total organic carbon profile (e.g. deviation of 33%) and the physicochemical phenomena observed in the process. In the model, it was also considered the variations of molecular weight of each biopolymer, successfully reproducing the biomass cleaving.


Assuntos
Celulose/química , Fracionamento Químico/métodos , Modelos Teóricos , Polissacarídeos/química , Biomassa , Biotecnologia/métodos , Fracionamento Químico/instrumentação , Desenho de Equipamento , Fagaceae/química , Cinética , Lignina/química , Temperatura , Água/química , Madeira/química
2.
Plant Dis ; 98(10): 1441, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30704005

RESUMO

Gray mold (Botrytis cinerea Pers.) is a major disease of grapevine (Vitis vinifera L.) worldwide. Integrated control strategies, including canopy management and fungicide treatments, are needed to control gray mold. Chemical control relies on the use of single mode of action fungicides. The aim of this research was to study the sensitivity of B. cinerea to boscalid, which is a single mode of action fungicide of the succinate dehydrogenase inhibitor (SDHI) fungicide group. Fifty isolates were obtained in 2012 to 2013 from commercial vineyards in central Chile. Vineyards had received two boscalid applications at least for four consecutive years. Briefly, the percent mycelial growth inhibition (MGI) was determined on minimal medium (MM) (2) plus 50 µg m-1 of boscalid (Cantus 50 WP, BASF Chile). Each isolate was tested in triplicate, obtaining 2% highly resistant (HR, MGI ≤25%), 32% moderately resistant (MR, MGI 26 to 50%), 64% low resistant (LR, MGI 51 to 80%), and 2% sensitive (S, MGI ≥81%) phenotypes. Nine isolates were arbitrary selected and compared for MGI on MM plus 50 µg ml-1 of boscalid (1) and conidial germination inhibition (CGI) on yeast extract-bacto peptone-Na acetate (YBA) plus 5 µg ml-1 of boscalid (2,3). Isolates previously determined to be S and HR had the same phenotype for both MGI and CGI. However, all of the MR and LR isolates, determined based on the MGI tests, were identified as S isolates in the CGI tests. Using primer-introduced restriction analysis (PIRA)-PCR (4), the SdhB mutations were detected only in the HR isolate. The amplifications were performed with H272L-fw/H272-rev and were digested by the enzyme BglII, yielding 35- and 85-bp fragments and confirming a mutation at codon 272 (H272L) in the HR phenotype. The efficacy of the label-rate (0.4 g liter-1) boscalid in controlling gray mold was determined on 'Granny Smith' apples. The apples were surface-disinfested (75% ethanol, 30 s), wounded with a sterile syringe, and inoculated with a mycelium plug (5 mm in diameter) or 20 µl of a conidial suspension (106 conidia/ml) of one HR, MR, and S isolate. The inoculum was placed on the wounded sites after boscalid application. Apples were incubated for 7 days at 21°C. Each test had four replicates and the experiment was conducted three times. Boscalid slightly controlled (<6.7% efficacy) gray mold on the apples that were inoculated with mycelium or conidia of the HR phenotype isolate, while the sensitive isolate was highly controlled (>95% efficacy), and the MR isolate was moderately controlled (27 to 34% efficacy). These results demonstrate that mycelium or conidia assays using MM + 50 µg ml-1 boscalid or YBA+5 µg ml-1 boscalid consistently detected HR isolates. The S isolates detected using MGI were also S according with the CGI tests. The presence of the boscalid HR strains of B. cinerea associated with the H272L mutation in grapevine in Chile is reported for the first time in this study. This finding suggests that resistance to boscalid needs to be considered in the design of gray mold control strategies in commercial grapevine orchards. References: (1) D. Fernandez-Ortuño et al Plant Dis. 96:1198, 2012. (2) M.-J. Hu et al. J. Phytopathol. 159:616, 2011. (3) Y. K. Kim and C. L. Xiao. Plant Dis. 94:604, 2010. (4) T. Veloukas et al. Plant Dis. 95:1302, 2011.

3.
Neurocirugia (Astur) ; 16(2): 124-33, 2005 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-15915302

RESUMO

Overdrainage in ventricular shunting constitutes a difficult to prevent and to treat complication. The authors reviewed a retrospective series of 512 children submitted to a ventricular shunting procedure aimed at analysing factors influencing this type of complication. The causes for the hydrocephalus were congenital (n=172), post-myelomeningocele (n=123), posthemorrhagic (n=103), tumoral (n=64), postmeningitis (n=40) and posttraumatic (n=10). Eighty-eight children (17.8%) evolved with a complication related to the excessive function of the valve. The authors investigated the relationship between hydrocephalus' etiology and type of overdrainage syndromes. The most frequent complication was ventricular catheter block (n=50), followed by symptomatic slit ventricle syndrome (SVS) (n=19), subdural hematoma (n=10) and trapped fourth ventricle (n=9). There were no statistical differences regarding complications for each etiologic subset of hydrocephalus. SVS occurred in 19 children (3.71%), a low rate according to the current literature. Posthemorrhagic and postinfectious hydrocephalus grouped together showed a higher rate of SVS (p=0.005), a feature that we attributed to the cerebral destruction caused by these two conditions. Treatment of SVS was complex and required diverse procedures, applied in an escalated way, which included five decompressive craniectomies. The authors suggest avoiding, as much as possible, the use of ventricular shunts, and recommend the alternative use of new technology valves and neuroendoscopic procedures.


Assuntos
Derivações do Líquido Cefalorraquidiano/efeitos adversos , Hidrocefalia/cirurgia , Complicações Pós-Operatórias/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/patologia , Incidência , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Complicações Pós-Operatórias/classificação , Estudos Retrospectivos , Síndrome , Tomografia Computadorizada por Raios X
4.
Neurocir. - Soc. Luso-Esp. Neurocir ; 16(2): 124-133, abr. 2005. ilus, tab
Artigo em Es | IBECS | ID: ibc-038305

RESUMO

El drenaje excesivo de las válvulas constituye una complicación dificil, tanto de prevenir como de tratar. Los autores revisan una serie de 512 niños operados mediante derivación de líquido cefalorraquídeo, de manera retrospectiva, para analizar las causas de esta complicación. La causa de la hidrocefalia fue congénita (n= 172), debida a mielomeningocele (n= 123), posthemorrágica (n=103), tumoral (n= 64), postinfecciosa (n=40) y postraumática (n= 10). Ochenta y ocho niños (17,8%) presentaron alguna complicación por funcionamiento excesivo del sistema valvular. Se analizó la etiología de la hidrocefalia relacionándola con los cuadros de hiperdrenaje. La complicación más frecuente fue la obstrucción del extremo ventricular de la derivación (n= 50), seguida del cuadro de colapso ventricular sintomático (n= 19), de hematoma subdural (n= 10) y de cuarto ventrículo aislado (n=9). Las diversas complicaciones se distribuyeron de manera homogénea entre todos los grupos etiológicos, sin diferencia estadística. El cuadro de colapso ventricular sintomático (CVS) ocurrió en 19 niños (3,71%), cifra menor que la descrita en la bibliografía. Sólo dos grupos de pacientes con hidrocefalia adquirida (postinfecciosa y posthemorrágica) tuvieron una mayor tasa de CVS (p=0,005), lo que se atribuyó a la mayor incidencia en estos niños de procesos destructivos cerebrales. El tratamiento del CVS fue complejo y requirió diversos procedimientos, que se aplicaron de manera escalonada, incluyendo cinco craniectomías descompresivas. Los autores recomiendan evitar, en lo posible, el empleo de válvulas, utilizando en su lugar, y siempre que sea posible, técnicas de neuroendoscopia, o válvulas de nueva tecnología, que supuestamente disminuirán el número de complicaciones de hiperfunción valvular


Overdrainage in ventricular shunting constitutes a difficult to prevent and to treat complication. The authors reviewed a retrospective series of 512 children submitted to a ventricular shunting procedure aimed at analysing factors influencing this type of complication. The causes for the hydrocephalus were congenital (n=172), post-myelomeningocele (n=123), posthemorrhagic (n=103), tumoral (n=64), postmeningitis (n=40) and posttraumatic (n=10). Eighty-eight children (17.8%) evolved with a complication related to the excessive function of the valve. The authors investigated the relationship between hydrocephalus' etiology and type of overdrainage syndromes. The most frequent complication was ventricular catheter block (n=50), followed by symptomatic slit ventricle syndrome (SVS) (n=19), subdural hematoma (n=10) and trapped fourth ventricle (n=9). There were no statistical differences regarding complications for each etiologic subset of hydrocephalus. SVS occurred in 19 children (3,71%), a low rate according to the current literature. Posthemorrhagic and postinfectious hydrocephalus grouped together showed a higher rate of SVS (p=0,005), a feature that we attributed to the cerebral destruction caused by these two conditions. Treatment of SVS was complex and required diverse procedures, applied in an escalated way, which included five decompressive craniectomies. The authors suggest avoiding, as much as possible, the use of ventricular shunts, and recommend the alternative use of new technology valves and neuroendoscopic procedures


Assuntos
Masculino , Feminino , Lactente , Criança , Humanos , Drenagem , Derivações do Líquido Cefalorraquidiano , Hidrocefalia/etiologia , Hidrocefalia/genética , Ventrículos Cerebrais/patologia , Derivação Ventriculoperitoneal , Neuroendoscopia , Hematoma Subdural/complicações , Microcefalia , Edema Encefálico
6.
Surg Neurol ; 55(5): 256-60, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11516459

RESUMO

BACKGROUND: Patients diagnosed with spina bifida may show late deterioration. This worsening in their clinical symptoms has been attributed to a multiplicity of causes such as secondary tethering of the spinal cord, Chiari II anomaly, hydromyelia, diastematomyelia, arachnoid cysts, and dermoid tumors. METHODS: We searched the clinical records of patients diagnosed with spina bifida who were treated at our hospital for a period of 25 years for the purpose of ascertaining the number and etiology of cases of late neurological deterioration. RESULTS: Six of 144 patients with open spina bifida presented with late neurological deterioration. In one of these cases and in another patient with occult spina bifida the most relevant factor noted during surgery was the presence of marked lumbar canal stenosis. CONCLUSION: We suggest that certain cases of late clinical worsening in spina bifida patients are because of lumbar canal stenosis and that this condition should be added to the list of causes that may produce delayed neurological deterioration in patients with spinal dysraphism.


Assuntos
Meningomielocele/complicações , Disrafismo Espinal/complicações , Estenose Espinal/diagnóstico , Estenose Espinal/fisiopatologia , Adulto , Diagnóstico Diferencial , Humanos , Região Lombossacral , Masculino , Meningomielocele/fisiopatologia , Meningomielocele/cirurgia , Radiografia , Disrafismo Espinal/fisiopatologia , Disrafismo Espinal/cirurgia , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/etiologia
7.
J Neurosurg ; 87(3): 468-71, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9285618

RESUMO

The authors present the case of a 6-year-old girl who developed a right frontal intradiploic meningoencephalocele following an accidental dural tear produced during surgery for craniosynostosis. Although rare, growing skull fractures have been described in at least eight cases following the accidental laceration of the dura mater in the course of craniosynostosis repair. These cases closely resemble those produced by accidental trauma to the growing skull. However, the intradiploic location of a meningoencephalocele following surgery for craniosynostosis has not been documented previously. This patient presented with headache and a frontal tumor of bonelike consistency. Radiographs and computerized tomography scans of the skull revealed an intraosseous cyst, whereas magnetic resonance imaging demonstrated cerebral tissue herniation within the intradiploic tumor. Surgical treatment consisted of duraplasty and cranioplasty, which achieved good functional and cosmetic results. The pathogenesis of this unusual lesion is discussed and compared with the hypotheses advanced for explaining posttraumatic intradiploic cysts.


Assuntos
Encefalocele , Meningocele , Criança , Encefalocele/diagnóstico por imagem , Encefalocele/patologia , Encefalocele/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Meningocele/diagnóstico por imagem , Meningocele/patologia , Meningocele/cirurgia , Tomografia Computadorizada por Raios X
8.
Acta Neurochir (Wien) ; 139(6): 585-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9248596

RESUMO

Atretic cephaloceles are usually detected at birth. Recently we treated a 38-year-old man with one of these lesions, apparently the first report of this occurrence in an adult.


Assuntos
Encefalocele/patologia , Couro Cabeludo/patologia , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino
9.
Acta Neurochir (Wien) ; 127(1-2): 65-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7942185

RESUMO

Thirty adult patients presenting with medulloblastoma between 1974 and 1991 were studied and treated at Puerta de Hierro Clinic. After diagnosis, all patients were treated by surgery followed by radiotherapy and eight of them received adjuvant chemotherapy. We have studied the influence of some factors such as age, sex, location of tumour in the cerebellum, amount of surgical resection and histological variants on survival and recurrence of the disease. Only the histological type has a statistically significant influence on survival and recurrence: we have found that patients presenting classic medulloblastoma have a long survival and a long relapse-free interval.


Assuntos
Neoplasias Cerebelares/cirurgia , Meduloblastoma/cirurgia , Adolescente , Adulto , Neoplasias Cerebelares/mortalidade , Neoplasias Cerebelares/patologia , Derivações do Líquido Cefalorraquidiano , Quimioterapia Adjuvante , Terapia Combinada , Irradiação Craniana , Feminino , Seguimentos , Humanos , Hidrocefalia/mortalidade , Hidrocefalia/patologia , Hidrocefalia/cirurgia , Masculino , Meduloblastoma/mortalidade , Meduloblastoma/patologia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Radioterapia Adjuvante , Estudos Retrospectivos , Taxa de Sobrevida
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