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1.
J Environ Manage ; 245: 489-495, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31170638

RESUMO

Anaerobic digestion (AD) in the beverage industry is a proven treatment technology. But adding dissolved organic matter to AD can increase the on-site output of renewable energy. In the tequila industry such waste-derived organic matter can be obtained from semisolid agave bagasse submitted to steam explosion as pretreatment. Vapor at pressure <1.0 MPa is commonly available so that steam explosion can be integrated into extant production schemes. This study investigates the efficiency of agave bagasse hydrolyzation via steam explosion (applying severity factors between 2.4 and 3.7 with 0.98 MPa maximum pressure) as well as the efficiency of the bio-conversion in anaerobic batch assays. The best steam explosion yield was 14.3 ±â€¯0.1 gCOD 100 g-1 (0.98 MPa vapor pressure during 22 min followed by fast pressure release). The average biochemical methane potential (BMP) was 290 mLN gCOD-1 with 74% of the biogas released within seven days.


Assuntos
Agave , Vapor , Anaerobiose , Biocombustíveis , Celulose , Metano , Extratos Vegetais
2.
Subst Abuse ; 13: 1178221819835847, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30944519

RESUMO

BACKGROUND: The importance of alcohol and cannabis consumption for the effectiveness of treatment of chronic hepatitis C virus (HCV) infection with direct acting antivirals (DAAs) in people on opioid substitution therapy (OST) has not been investigated in detail. METHODS: We investigated sustained virological response (SVR) rates and proportion of lost to follow-up (LTFU) between OST (n = 739) and non-OST patients (n = 7008) in the German Hepatitis C-Registry (Deutsches Hepatitis C-Register, DHC-R), which is a national multicenter prospective non-interventional real-world registry. Non-OST patients comprised patients with former/current drug use (non-OST/DU; n = 1500) and patients never consuming drugs (non-OST/NDU; n = 5508). FINDINGS: SVR 12/24 rates (intention to treat [ITT]) in patients consuming no or less than 30 g/day (women) or 40 g/day (men) were significantly higher in non-OST/NDU (range 91%-92%) vs OST patients (range 83%-86%), mainly due to significantly higher LTFU rates in OST (range 11%-12%) compared with non-OST/NDU (range 2%-3%). In non-OST/NDU with high alcohol consumption of more than 30/40 g/day, SVR 12/24 rates (ITT) were lower (85%) but did not differ to OST (85%) with high alcohol consumption. No significant differences could be seen for SVR 12/24 in per-protocol (PP) analysis independent of alcohol consumption or amount of alcohol intake. Cannabis use did not significantly influence SVR 12/24 in ITT or PP or LTFU. CONCLUSIONS: High SVR rates could be achieved in both OST and non-OST patients irrespective of alcohol or cannabis consumption. However, LTFU is more likely in patients with current or former drug use than in patients without drug history and in patients with high alcohol consumption but occurred mainly after end of antiviral treatment (EOT), leaving a high chance for HCV elimination in these patients.

3.
Ann Neurol ; 77(5): 760-74, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25627477

RESUMO

OBJECTIVE: There are competing explanations for persistent postoperative seizures after temporal lobe surgery. One is that 1 or more particular subtypes of mesial temporal lobe epilepsy (mTLE) exist that are particularly resistant to surgery. We sought to identify a common brain structural and connectivity alteration in patients with persistent postoperative seizures using preoperative quantitative magnetic resonance imaging and diffusion tensor imaging (DTI). METHODS: We performed a series of studies in 87 patients with mTLE (47 subsequently rendered seizure free, 40 who continued to experience postoperative seizures) and 80 healthy controls. We investigated the relationship between imaging variables and postoperative seizure outcome. All patients had unilateral temporal lobe seizure onset, had ipsilateral hippocampal sclerosis as the only brain lesion, and underwent amygdalohippocampectomy. RESULTS: Quantitative imaging factors found not to be significantly associated with persistent seizures were volumes of ipsilateral and contralateral mesial temporal lobe structures, generalized brain atrophy, and extent of resection. There were nonsignificant trends for larger amygdala and entorhinal resections to be associated with improved outcome. However, patients with persistent seizures had significant atrophy of bilateral dorsomedial and pulvinar thalamic regions, and significant alterations of DTI-derived thalamotemporal probabilistic paths bilaterally relative to those patients rendered seizure free and controls, even when corrected for extent of mesial temporal lobe resection. INTERPRETATION: Patients with bihemispheric alterations of thalamotemporal structural networks may represent a subtype of mTLE that is resistant to temporal lobe surgery. Increasingly sensitive multimodal imaging techniques should endeavor to transform these group-based findings to individualize prediction of patient outcomes.


Assuntos
Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/cirurgia , Convulsões/diagnóstico , Lobo Temporal/patologia , Lobo Temporal/cirurgia , Tálamo/patologia , Adulto , Epilepsia do Lobo Temporal/complicações , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Convulsões/etiologia , Resultado do Tratamento
4.
Brain Cogn ; 91: 35-44, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25222292

RESUMO

In daily life, responses are often facilitated by anticipatory imagery of expected targets which are announced by associated stimuli from different sensory modalities. Silent music reading represents an intriguing case of visuotonal modality transfer in working memory as it induces highly defined auditory imagery on the basis of presented visuospatial information (i.e. musical notes). Using functional MRI and a delayed sequence matching-to-sample paradigm, we compared brain activations during retention intervals (10s) of visual (VV) or tonal (TT) unimodal maintenance versus visuospatial-to-tonal modality transfer (VT) tasks. Visual or tonal sequences were comprised of six elements, white squares or tones, which were low, middle, or high regarding vertical screen position or pitch, respectively (presentation duration: 1.5s). For the cross-modal condition (VT, session 3), the visuospatial elements from condition VV (session 1) were re-defined as low, middle or high "notes" indicating low, middle or high tones from condition TT (session 2), respectively, and subjects had to match tonal sequences (probe) to previously presented note sequences. Tasks alternately had low or high cognitive load. To evaluate possible effects of music reading expertise, 15 singers and 15 non-musicians were included. Scanner task performance was excellent in both groups. Despite identity of applied visuospatial stimuli, visuotonal modality transfer versus visual maintenance (VT>VV) induced "inhibition" of visual brain areas and activation of primary and higher auditory brain areas which exceeded auditory activation elicited by tonal stimulation (VT>TT). This transfer-related visual-to-auditory activation shift occurred in both groups but was more pronounced in experts. Frontoparietal areas were activated by higher cognitive load but not by modality transfer. The auditory brain showed a potential to anticipate expected auditory target stimuli on the basis of non-auditory information and sensory brain activation rather mirrored expectation than stimulation. Silent music reading probably relies on these basic neurocognitive mechanisms.


Assuntos
Percepção Auditiva/fisiologia , Mapeamento Encefálico , Memória de Curto Prazo/fisiologia , Música , Leitura , Canto/fisiologia , Estimulação Acústica/métodos , Adolescente , Adulto , Córtex Auditivo/fisiologia , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Adulto Jovem
5.
Eur Spine J ; 22(9): 1958-64, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23392554

RESUMO

PURPOSE: Chronic low back pain (CLBP) is one of the most important pain disorders with increasing social and economic implications. Given that CLBP is a multidimensional process associated with comorbidities such as anxiety and depression, treatment of chronic low back pain is still a challenge. Advancement of in vivo brain imaging technologies has revealed increasing insights into the etiology and pathogenesis of chronic pain; however, the exact mechanisms of chronification of LBP remain still unclear. The purpose of the present study was to analyse the neurostructural alterations in CLBP and to evaluate the role of comorbidities and their neurostructural underpinnings. METHODS: In the present study we investigated a well-characterized group of 14 patients with CLBP and 14 healthy controls applying structural MRI and psychometric measures. Using an improved algorithm for brain normalization (DARTEL) we performed a voxel-based morphometry (VBM) approach. Correlation analyses were performed to evaluate the role of anxiety and depression in neurostructural alterations observed in CLBP. RESULTS: The psychometric measures revealed significantly higher scores on depression and anxiety in the patient population. VBM analysis showed significant decreases in grey matter density in areas associated with pain processing and modulation, i.e. the dorsolateral prefrontal cortex, the thalamus and the middle cingulate cortex. With respect to anxiety and depression scores, we did not observe any correlations to the structural data. CONCLUSIONS: In the present study we found compelling evidence for alterations of grey matter architecture in CLBP in brain regions playing a major role in pain modulation and control. Our results fit the hypothesis of a "brain signature" in chronic pain conditions. The results of the psychometric assessment underline the importance of an interdisciplinary therapeutic approach including orthopedic, neurological and psychological evaluation and treatment.


Assuntos
Dor Lombar/fisiopatologia , Dor Lombar/psicologia , Plasticidade Neuronal/fisiologia , Córtex Pré-Frontal/fisiologia , Psicometria , Tálamo/fisiologia , Adulto , Idoso , Dor Crônica/epidemiologia , Dor Crônica/fisiopatologia , Dor Crônica/psicologia , Comorbidade , Avaliação da Deficiência , Feminino , Humanos , Dor Lombar/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/citologia , Tálamo/citologia
6.
PLoS One ; 7(10): e46791, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23071638

RESUMO

BACKGROUND: In patients with temporal lobe epilepsy and associated hippocampal sclerosis (TLEhs) there are brain abnormalities extending beyond the presumed epileptogenic zone as revealed separately in conventional magnetic resonance imaging (MRI) and MR diffusion tensor imaging (DTI) studies. However, little is known about the relation between macroscopic atrophy (revealed by volumetric MRI) and microstructural degeneration (inferred by DTI). METHODOLOGY/PRINCIPAL FINDINGS: For 62 patients with unilateral TLEhs and 68 healthy controls, we determined volumes and mean fractional anisotropy (FA) of ipsilateral and contralateral brain structures from T1-weighted and DTI data, respectively. We report significant volume atrophy and FA alterations of temporal lobe, subcortical and callosal regions, which were more diffuse and bilateral in patients with left TLEhs relative to right TLEhs. We observed significant relationships between volume loss and mean FA, particularly of the thalamus and putamen bilaterally. When corrected for age, duration of epilepsy was significantly correlated with FA loss of an anatomically plausible route - including ipsilateral parahippocampal gyrus and temporal lobe white matter, the thalamus bilaterally, and posterior regions of the corpus callosum that contain temporal lobe fibres - that may be suggestive of progressive brain degeneration in response to recurrent seizures. CONCLUSIONS/SIGNIFICANCE: Chronic TLEhs is associated with interrelated DTI-derived and volume-derived brain degenerative abnormalities that are influenced by the duration of the disorder and the side of seizure onset. This work confirms previously contradictory findings by employing multi-modal imaging techniques in parallel in a large sample of patients.


Assuntos
Encéfalo/anormalidades , Imagem de Tensor de Difusão/métodos , Epilepsia do Lobo Temporal/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Anisotropia , Atrofia/complicações , Epilepsia do Lobo Temporal/complicações , Feminino , Hipocampo/patologia , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Lobo Temporal/patologia , Tálamo/patologia , Fatores de Tempo
7.
Epilepsy Behav ; 10(3): 442-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17368108

RESUMO

The medial temporal lobes (MTLs) are essential for both encoding and retrieval processes in declarative memory. In addition, they are a frequent seizure focus for medically refractory epilepsy. One of the major side effects of MTL resection is a decline in memory functions. Most functional imaging paradigms have been developed to find preoperative measures that, to obtain a prognosis of postoperative memory performance, employ explicit memory encoding strategies to elicit MTL activation, and require a great amount of cognitive effort. We applied three different implicit encoding tasks, which require less effort and time, to a group of healthy subjects. We found left-lateralized activation for verbal stimuli, bilateral activation for pictures, and right-lateralized activation for faces. The present study shows that even with an implicit memory-encoding paradigm, a lateralized activation of MTL structures can be achieved. This may lead to paradigms for routine clinical application that require less cognitive effort and time on the part of patients.


Assuntos
Mapeamento Encefálico , Lateralidade Funcional/fisiologia , Memória/fisiologia , Lobo Temporal/fisiologia , Estimulação Acústica/métodos , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Oxigênio/sangue , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Lobo Temporal/irrigação sanguínea , Aprendizagem Verbal/fisiologia
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