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1.
Health Policy ; 129: 104699, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36566153

RESUMEN

Since the Dutch tolerance policy, allowing the purchase of cannabis in 'coffeeshops', is associated with problems of public order and safety as well as health risks, there has been a long debate about legalisation of cannabis production and supply. It was therefore decided to conduct an experiment with a controlled legal ('closed') cannabis supply chain for recreational use. This is of international relevance in view of the current illegal cannabis exports from the Netherlands, the importance of sharing knowledge about the effectiveness of cannabis policies, and the accumulation of evidence needed to evaluate and update international treaties. Here we describe and discuss the background, general approach and design of the experiment. An independent expert committee elaborated how the closed chain will operate and be evaluated, based on the experience with the medicinal cannabis chain, and round table discussions with stakeholders (mayors, coffeeshop owners, cannabis consumers, growers, regulators, scientists, and addiction experts). Ten trusted cannabis growers are contracted to produce and supply cannabis to the coffeeshops in intervention municipalities, with product quality control, law enforcement against criminal interference, and preventive efforts to reduce health risks being implemented. No changes will be made in the cannabis supply to the coffeeshops in participating control municipalities. A process evaluation will assess whether the chain from production to sale in the intervention municipalities was really closed. In a quasi-experimental study comparing intervention and control municipalities, the chain's effects on public health, cannabis-related crime, safety and public nuisance will be estimated. The fieldwork period is expected to start early 2024 and will take four years, including reporting to the government and parliament. These will then decide whether and what further steps towards legalisation of the production and supply of cannabis will be taken.


Asunto(s)
Cannabis , Humanos , Países Bajos , Políticas , Salud Pública , Comercio , Legislación de Medicamentos
2.
Biomolecules ; 12(2)2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35204652

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) and their N- and O-containing derivatives (N-/O-PAHs) are environmental pollutants and synthetically attractive building blocks in pharmaceuticals. Functionalization of PAHs can be achieved via C-H activation by cytochrome P450 enzymes (e.g., P450 CYP3A4) in an environmentally friendly manner. Despite its broad substrate scope, the contribution of CYP3A4 to metabolize common PAHs in humans was found to be small. We recently showcased the potential of CYP3A4 in whole-cell biocatalysis with recombinant yeast Komagataella phaffii (Pichia pastoris) catalysts for the preparative-scale synthesis of naturally occurring metabolites in humans. In this study, we aimed at exploring the substrate scope of CYP3A4 towards (N-/O)-PAHs and conducted a bioconversion experiment at 10 L scale to validate the synthetic potential of CYP3A4 for the preparative-scale production of functionalized PAH metabolites. Hydroxylated products were purified and characterized using HPLC and NMR analysis. In total, 237 mg of fluorenol and 48 mg of fluorenone were produced from 498 mg of fluorene, with peak productivities of 27.7 µmol/L/h for fluorenol and 5.9 µmol/L/h for fluorenone; the latter confirmed that CYP3A4 is an excellent whole-cell biocatalyst for producing authentic human metabolites.


Asunto(s)
Citocromo P-450 CYP3A , Hidrocarburos Policíclicos Aromáticos , Reactores Biológicos , Citocromo P-450 CYP3A/química , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/metabolismo , Humanos , Hidrocarburos Policíclicos Aromáticos/química , Hidrocarburos Policíclicos Aromáticos/metabolismo
3.
Biochem Biophys Res Commun ; 595: 35-40, 2022 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-35093638

RESUMEN

In a previous study, we identified CYP5035S7 of the white-rot fungus Polyporus arcularius with a broad activity towards monoterpenes such as p-cymene. Therefore, in this study we aimed at further exploring the substrate scope of detoxifying CYP5035S7 towards terpenes and semi-preparatively isolating some of the products via whole-cell biotransformation, in order to obtain information about the enzyme's reactivity. We noticed a clear preference for the monoterpene skeleton and elucidated a distinct regioselectivity pattern based on key structural and electronic features of its substrates. This study illustrates how minimal characterisation effort may already suffice to provide vital information on enzymatic reactivity by the comparison of structural derivatives.


Asunto(s)
Carbono/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Proteínas Fúngicas/metabolismo , Monoterpenos/metabolismo , Polyporus/metabolismo , Biotransformación , Carbono/química , Hidroxilación , Estructura Molecular , Monoterpenos/química , Estereoisomerismo , Especificidad por Sustrato
4.
Mol Carcinog ; 61(1): 5-18, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34587660

RESUMEN

Elevated preoperative plasma level of endoglin has been associated with worse oncologic outcomes in various malignancies. The present large-scale study aimed to determine the predictive and prognostic values of preoperative endoglin with regard to clinicopathologic and survival outcomes in patients treated with radical cystectomy (RC) for nonmetastatic urothelial carcinoma of the bladder (UCB). We prospectively collected preoperative blood samples from 1036 consecutive patients treated with RC for UCB. Logistic and Cox regression analyses were undertaken to assess the correlation of endoglin levels with pathologic and survival outcomes, respectively. The AUC and C-index were used to assess the discrimination. Patients with adverse pathologic features had significantly higher median preoperative endoglin plasma levels than their counterparts. Higher preoperative endoglin level was independently associated with an increased risk for lymph node metastasis, ≥pT3 disease, and nonorgan confined disease (NOCD; all p < 0.001). Plasma endoglin level was also independently associated with cancer-specific and overall survival in both pre- and postoperative models (all p < 0.05), as well as with recurrence-free survival (RFS) in the preoperative model (p < 0.001). The addition of endoglin to the preoperative standard model improved its discrimination for prediction of lymph node metastasis, ≥pT3 disease, NOCD, and RFS (differential increases in C-indices: 10%, 5%, 5.8%, and 4%, respectively). Preoperative plasma endoglin is associated with features of biologically and clinically aggressive UCB as well as survival outcomes. Therefore, it seems to hold the potential of identifying UCB patients who may benefit from intensified therapy in addition to RC such as extended lymphadenectomy or/and preoperative systemic therapy.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma de Células Transicionales/cirugía , Endoglina/sangre , Neoplasias de la Vejiga Urinaria/cirugía , Anciano , Carcinoma de Células Transicionales/sangre , Carcinoma de Células Transicionales/patología , Cistectomía , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Periodo Preoperatorio , Pronóstico , Estudios Prospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/sangre , Neoplasias de la Vejiga Urinaria/patología
5.
Biomolecules ; 11(11)2021 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-34827706

RESUMEN

Functionalisation of polycyclic aromatic hydrocarbons (PAHs) and their N-heteroarene analogues (NPAHs) is a tedious synthetic endeavour that requires diverse bottom-up approaches. Cytochrome P450 enzymes of white-rot fungi were shown to participate in the fungal detoxification of xenobiotics and environmental hazards via hydroxylation of PAH compounds. In this paper, the recently discovered activity of the monooxygenase CYP5035S7 towards (N)PAHs was investigated in detail, and products formed from the substrates azulene, acenaphthene, fluorene, anthracene, and phenanthrene by whole-cell biocatalysis were isolated and characterised. The observed regioselectivity of CYP5035S7 could be explained by a combination of the substrate's electron density and steric factors influencing the substrate orientation giving insight into the active-site geometry of the enzyme.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Basidiomycota , Sistema Enzimático del Citocromo P-450 , Fenantrenos , Polyporus
6.
Urol Oncol ; 39(11): 764-773, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34400065

RESUMEN

PURPOSE: Tyrosine kinase inhibitors (TKIs) have been widely used in the management of patients with metastatic renal cell carcinoma (RCC). However, the use of systemic therapies in the adjuvant setting of localized and locally advanced RCC has shown conflicting results across the literature. Therefore, we aimed to conduct an updated systematic review and meta-analysis comparing the efficacy and safety of TKIs in the adjuvant setting for patients with localized and locally advanced RCC. MATERIALS AND METHODS: The MEDLINE and EMBASE databases were searched in December 2020 to identify phase III randomized controlled trials of patients receiving adjuvant therapies with TKI for RCC. Disease-free survival (DFS) and overall survival (OS) were the primary endpoints. The secondary endpoints included treatment-related adverse events (TRAEs) of high and any grade. RESULTS: Five trials (S-TRAC, ASSURE, PROTECT, ATLAS, and SORCE) were included in our meta-analysis comprising 6,531 patients. The forest plot revealed that TKI therapy was associated with a significantly longer DFS compared to placebo (pooled HR: 0.88, 95% CI: 0.81-0.96, P= 0.004). The Cochrane's Q test (P = 0.51) and I2 test (I2 = 0%) revealed no significant heterogeneity. Adjuvant TKI was not associated with improved OS compared to placebo (pooled HR: 0.93, 95% CI: 0.83-1.04, P= 0.23). The Cochrane's Q test (P = 0.74) and I2 test (I2 = 0%) revealed no significant heterogeneity. The forest plot revealed that TKI therapy, compared to placebo, was associated with higher rates of high grade TRAEs (OR: 5.20, 95% CI: 4.10-6.59, P< 0.00001) as well as any grade TRAEs (OR: 3.85, 95% CI: 1.22-12.17, P= 0.02). The Cochrane's Q tests (P < 0.0001 and P < 0.00001, respectively) and I2 tests (I2 = 79% and I2 = 90%, respectively) revealed significant heterogeneity. CONCLUSIONS: The findings of our analyses suggest an improved DFS in patients with localized and locally advanced RCC receiving adjuvant TKI as compared to placebo; however, this did not translate into any significant OS benefit. Additionally, TKI therapy led to significant toxicity. Adjuvant TKI does not seem to offer a satisfactory risk and/orbenefit balance for all patients. Select patients with very poor prognosis may be considered in a shared decision-making process with the patient. With the successful arrival of immune-based therapies in RCC, these may allow a more favorable risk/benefit profile.


Asunto(s)
Carcinoma de Células Renales/tratamiento farmacológico , Quimioterapia Adyuvante/métodos , Neoplasias Renales/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Carcinoma de Células Renales/mortalidad , Carcinoma de Células Renales/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Renales/mortalidad , Neoplasias Renales/patología , Masculino , Inhibidores de Proteínas Quinasas/farmacología
7.
Appl Microbiol Biotechnol ; 105(18): 6779-6792, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34459954

RESUMEN

Bioprospecting for innovative basidiomycete cytochrome P450 enzymes (P450s) is highly desirable due to the fungi's enormous enzymatic repertoire and outstanding ability to degrade lignin and detoxify various xenobiotics. While fungal metagenomics is progressing rapidly, the biocatalytic potential of the majority of these annotated P450 sequences usually remains concealed, although functional profiling identified several P450 families with versatile substrate scopes towards various natural products. Functional knowledge about the CYP5035 family, for example, is largely insufficient. In this study, the families of the putative P450 sequences of the four white-rot fungi Polyporus arcularius, Polyporus brumalis, Polyporus squamosus and Lentinus tigrinus were assigned, and the CYPomes revealed an unusual enrichment of CYP5035, CYP5136 and CYP5150. By computational analysis of the phylogeny of the former two P450 families, the evolution of their enrichment could be traced back to the Ganoderma macrofungus, indicating their evolutionary benefit. In order to address the knowledge gap on CYP5035 functionality, a representative subgroup of this P450 family of P. arcularius was expressed and screened against a test set of substrates. Thereby, the multifunctional enzyme CYP5035S7 converting several plant natural product classes was discovered. Aligning CYP5035S7 to 102,000 putative P450 sequences of 36 fungal species from Joint Genome Institute-provided genomes located hundreds of further CYP5035 family members, which subfamilies were classified if possible. Exemplified by these specific enzyme analyses, this study gives valuable hints for future bioprospecting of such xenobiotic-detoxifying P450s and for the identification of their biocatalytic potential. KEY POINTS: • The P450 families CYP5035 and CYP5136 are unusually enriched in P. arcularius. • Functional screening shows CYP5035 assisting in the fungal detoxification mechanism. • Some Polyporales encompass an unusually large repertoire of detoxification P450s.


Asunto(s)
Basidiomycota , Polyporales , Basidiomycota/genética , Sistema Enzimático del Citocromo P-450/genética , Evolución Molecular , Genoma Fúngico , Lentinula , Filogenia , Polyporales/genética , Polyporus
8.
Urol Oncol ; 39(12): 806-815, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34266740

RESUMEN

We aimed to conduct a systematic review and meta-analysis assessing the incidence and risk factors of urethral recurrence (UR) as well as summarizing data on survival outcomes in patients with UR after radical cystectomy (RC) for bladder cancer. The MEDLINE and EMBASE databases were searched in February 2021 for studies of patients with UR after RC. Incidence and risk factors of UR were the primary endpoints. The secondary endpoint was survival outcomes in patients who experienced UR. Twenty-one studies, comprising 9,435 patients, were included in the quantitative synthesis. Orthotopic neobladder (ONB) diversion was associated with a decreased probability of UR compared to non-ONB (pooled OR: 0.44, 95% CI: 0.31-0.61, P < 0.001) and male patients had a significantly higher risk of UR compared to female patients (pooled OR: 3.16, 95% CI: 1.83-5.47, P < 0.001). Among risk factors, prostatic urethral or prostatic stromal involvement (pooled HR: 5.44, 95% CI: 3.58-8.26, P < 0.001; pooled HR: 5.90, 95% CI: 1.82-19.17, P = 0.003, respectively) and tumor multifocality (pooled HR: 2.97, 95% CI: 2.05-4.29, P < 0.001) were associated with worse urethral recurrence-free survival. Neither tumor stage (P = 0.63) nor CIS (P = 0.72) were associated with worse urethral recurrence-free survival. Patients with UR had a 5-year CSS that varied from 47% to 63% and an OS - from 40% to 74%; UR did not appear to be related to worse survival outcomes. Male patients treated with non-ONB diversion as well as patients with prostatic involvement and tumor multifocality seem to be at the highest risk of UR after RC. Risk-adjusted standardized surveillance protocols should be developed into clinical practice after RC.


Asunto(s)
Cistectomía/métodos , Neoplasias de la Vejiga Urinaria/cirugía , Femenino , Humanos , Incidencia , Masculino , Recurrencia Local de Neoplasia , Factores de Riesgo , Resultado del Tratamiento
9.
ChemCatChem ; 11(9): 2226-2242, 2019 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-31423290

RESUMEN

The biological potency of natural products has been exploited for decades. Their inherent structural complexity and natural diversity might hold the key to efficiently address the urgent need for the development of novel pharmaceuticals. At the same time, it is that very complexity, which impedes necessary chemical modifications such as structural diversification, to improve the effectiveness of the drug. For this purpose, Cytochrome P450 enzymes, which possess unique abilities to activate inert sp3-hybridised C-H bonds in a late-stage fashion, offer an attractive synthetic tool. In this review the potential of cytochrome P450 enzymes in chemoenzymatic lead diversification is illustrated discussing studies reporting late-stage functionalisations of natural products and other high-value compounds. These enzymes were proven to extend the synthetic toolbox significantly by adding to the flexibility and efficacy of synthetic strategies of natural product chemists, and scientists of other related disciplines.

10.
Elife ; 72018 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-30465650

RESUMEN

Sensory navigation results from coordinated transitions between distinct behavioral programs. During chemotaxis in the Drosophila melanogaster larva, the detection of positive odor gradients extends runs while negative gradients promote stops and turns. This algorithm represents a foundation for the control of sensory navigation across phyla. In the present work, we identified an olfactory descending neuron, PDM-DN, which plays a pivotal role in the organization of stops and turns in response to the detection of graded changes in odor concentrations. Artificial activation of this descending neuron induces deterministic stops followed by the initiation of turning maneuvers through head casts. Using electron microscopy, we reconstructed the main pathway that connects the PDM-DN neuron to the peripheral olfactory system and to the pre-motor circuit responsible for the actuation of forward peristalsis. Our results set the stage for a detailed mechanistic analysis of the sensorimotor conversion of graded olfactory inputs into action selection to perform goal-oriented navigation.


Asunto(s)
Conducta Animal , Quimiotaxis , Drosophila melanogaster/citología , Corteza Sensoriomotora/fisiología , Animales , Bioensayo , Pruebas Genéticas , Larva/citología , Locomoción/fisiología , Actividad Motora/fisiología , Neuronas Motoras/fisiología , Neuronas Receptoras Olfatorias/fisiología , Neuronas Receptoras Olfatorias/ultraestructura , Optogenética , Peristaltismo , Fenotipo , Olfato/fisiología
11.
Sports Med ; 47(10): 2045-2068, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28386652

RESUMEN

BACKGROUND: Proficiency in fundamental movement skills (FMS) lays the foundation for being physically active and developing more complex motor skills. Improving these motor skills may provide enhanced opportunities for the development of a variety of perceptual, social, and cognitive skills. OBJECTIVE: The objective of this systematic review and meta-analysis was to assess the effects of FMS interventions on actual FMS, targeting typically developing young children. METHOD: Searches in seven databases (CINAHL, Embase, MEDLINE, PsycINFO, PubMed, Scopus, Web of Science) up to August 2015 were completed. Trials with children (aged 2-6 years) in childcare or kindergarten settings that applied FMS-enhancing intervention programs of at least 4 weeks and meeting the inclusion criteria were included. Standardized data extraction forms were used. Risk of bias was assessed using a standard scoring scheme (Effective Public Health Practice Project-Quality Assessment Tool for Quantitative Studies [EPHPP]). We calculated effects on overall FMS, object control and locomotor subscales (OCS and LMS) by weighted standardized mean differences (SMDbetween) using random-effects models. Certainty in training effects was evaluated using GRADE (Grading of Recommendations Assessment, Development, and Evaluation System). RESULTS: Thirty trials (15 randomized controlled trials and 15 controlled trials) involving 6126 preschoolers (aged 3.3-5.5 years) revealed significant differences among groups in favor of the intervention group (INT) with small-to-large effects on overall FMS (SMDbetween 0.46), OCS (SMDbetween 1.36), and LMS (SMDbetween 0.94). Our certainty in the treatment estimates based on GRADE is very low. CONCLUSIONS: Although there is relevant effectiveness of programs to improve FMS proficiency in healthy young children, they need to be interpreted with care as they are based on low-quality evidence and immediate post-intervention effects without long-term follow-up.


Asunto(s)
Ejercicio Físico , Actividad Motora/fisiología , Destreza Motora/fisiología , Movimiento/fisiología , Niño , Preescolar , Humanos , Instituciones Académicas , Estudiantes
12.
Angew Chem Int Ed Engl ; 56(21): 5760-5764, 2017 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-28444918

RESUMEN

The first catalytic kinetic resolution by N-sulfonylation is described. 2-Substituted indolines are resolved (s=2.6-19) using an atropisomeric 4-dimethylaminopyridine-N-oxide (4-DMAP-N-oxide) organocatalyst. Use of 2-isopropyl-4-nitrophenylsulfonyl chloride is critical to the stereodiscrimination and enables facile deprotection of the sulfonamide products with thioglycolic acid. A qualitative model that accounts for the stereodiscrimination is proposed.

13.
Artículo en Inglés | MEDLINE | ID: mdl-23221232

RESUMEN

Phospholipid-coated ultrasound contrast agents may deflate or even collapse because of stress resulting from ultrasound-induced oscillations. In this work, we investigate the behavior of isolated contrast agent microbubbles during prolonged ultrasound excitation. Isolated microbubbles placed in a thin capillary tube were excited with hundreds of ultrasound pulses at a low mechanical index, and their oscillations were recorded using the Brandaris-128 ultra-high-speed camera. Results show that microbubbles undergo an irreversible, non-destructive deflation process. Such deflation seems to occur in discrete steps rather than as a continuous process; furthermore, the dynamics of the bubble change during deflation: radial oscillations, both symmetric and asymmetric around the resting radius of the bubble, occur at various stages of the deflation process. Strongly asymmetric oscillations, such as compression-only and expansion-only behavior, were also observed: notably, expansion-only behavior is associated with a rapid size reduction, whereas compression-only behavior mostly occurs without a noticeable change of the bubble radius. We hypothesize that bubble deflation results from at least two distinct phenomena, namely diffusive gas loss and lipid material shedding from the encapsulating shell.


Asunto(s)
Medios de Contraste/química , Gases/química , Microburbujas , Difusión , Modelos Teóricos , Fosfolípidos/química , Presión , Ultrasonografía
14.
Hum Mov Sci ; 30(2): 341-51, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21453667

RESUMEN

The concept of body schema has been introduced and widely discussed in the literature to explain various clinical observations and distortions in the body and space representation. Here we address the role of body schema related information in multi-joint limb motion. The processing of proprioceptive information may differ significantly in static and dynamic conditions since in the latter case the control system may employ specific dynamic rules and constraints. Accordingly, the perception of movement, e.g., estimation of step length and walking distance, may rely on a priori knowledge about intrinsic dynamics of limb segment motion and inherent relationships between gait parameters and body proportions. The findings are discussed in the general framework of space and body movement representation and suggest the existence of a dynamic locomotor body schema used for controlling step length and path estimation.


Asunto(s)
Marcha/fisiología , Cinestesia/fisiología , Orientación/fisiología , Propiocepción/fisiología , Caminata/fisiología , Fenómenos Biomecánicos , Imagen Corporal , Encéfalo/fisiología , Humanos , Articulaciones/inervación , Músculo Esquelético/inervación , Analizadores Neurales/fisiología , Desempeño Psicomotor/fisiología , Médula Espinal/fisiología
15.
Psychol Med ; 40(9): 1531-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19917144

RESUMEN

BACKGROUND: Patients with anorexia nervosa (AN) overestimate their size despite being severely underweight. Whether this misperception echoes an underlying emotional disturbance or also reflects a genuine body-representation deficit is debatable. Current measures inquire directly about subjective perception of body image, thus distinguishing poorly between top-down effects of emotions/attitudes towards the body and disturbances due to proprioceptive disorders/distorted body schema. Disorders of body representation also emerge following damage to the right parietal lobe. The possibility that parietal dysfunction might contribute to AN is suspected, based on the demonstrated association of spatial impairments, comparable to those found after parietal lesion, with this syndrome. METHOD: We used a behavioral task to compare body knowledge in severe anorexics (n=8), healthy volunteers (n=11) and stroke patients with focal damage to the left/right parietal lobe (n=4). We applied a psychophysical procedure based on the perception, in the dark, of an approaching visual stimulus that was turned off before reaching the observer. Participants had to predict whether the stimulus would have hit/missed their body, had it continued its linear motion. RESULTS: Healthy volunteers and left parietal patients estimated body boundaries very close to the real ones. Conversely, anorexics and right parietal patients underestimated eccentricity of their left body boundary. CONCLUSIONS: These findings are in line with the role the parietal cortex plays in developing and maintaining body representation, and support the possibility for a neuropsychological component in the pathogenesis of anorexia, offering alternative approaches to treatment of the disorder.


Asunto(s)
Anorexia Nerviosa/patología , Trastorno Dismórfico Corporal/patología , Lóbulo Parietal/patología , Trastornos de la Percepción/patología , Adulto , Anorexia Nerviosa/psicología , Ganglios Basales/patología , Estudios de Casos y Controles , Femenino , Humanos , Corteza Somatosensorial/patología
16.
Neuropsychologia ; 46(7): 1898-907, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18316102

RESUMEN

We tested navigational abilities of brain-damaged patients suffering from representational or perceptual neglect asking them to retrieve a location according to salient spatial cues included in a rectangular empty room. Both groups of patients showed difficulties in learning the spatial definition of the target location in relation to two landmarks. However in a delayed attempt performed after several trials the group of patients with perceptual neglect proved able to easily retrieve the target location. In this condition they performed as controls showing a spared ability to navigate according to a stable representation of the room in long-term memory. In contrast the difficulty of patients with representational neglect remained unchanged across experimental conditions. At variance with clinical assessment, in which patients show asymmetrical performances in describing a well-known environment from memory, this latter result depicts a behavioural counterpart of the disorder, namely the inability to orient in a new environment according to an inner representation. Data are further discussed in order to provide a description of the cognitive mechanisms required for space representation for navigation.


Asunto(s)
Daño Encefálico Crónico/fisiopatología , Señales (Psicología) , Orientación/fisiología , Trastornos de la Percepción/diagnóstico , Adulto , Anciano , Grupos Control , Conducta Exploratoria/fisiología , Femenino , Percepción de Forma/fisiología , Lateralidad Funcional/fisiología , Humanos , Masculino , Aprendizaje por Laberinto/fisiología , Memoria/fisiología , Persona de Mediana Edad , Pruebas Neuropsicológicas , Trastornos de la Percepción/fisiopatología , Estimulación Luminosa , Tiempo de Reacción/fisiología , Percepción Espacial/fisiología
17.
Vaccine ; 25(4): 649-58, 2007 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-17014936

RESUMEN

The CP05 saponin from Calliandra pulcherrima Benth, shows remarkable similarities to the QS21 saponin of Quillaja saponaria Molina. Both shared a monoterpene hydrophobic moiety, a glycidic chain attached to the triterpene C28, and three sugars attached to C3. Different from QS21, the CP05 does not show the aldehyde group in triterpene C4 involved in TH1 response. Balb/c mice were immunized either intact saponin (CP05), the monoterpene-deprived (BS), the C28 carbohydrate-deprived (HS) or the sapogenin fraction, in formulation with the FML antigen of Leishmania donovani and challenged with 2 x 10(8) amastigotes of L. chagasi. While the CP05 induced 90% survival and 92.1% parasite reduction, a 100% survival and 94.1% protection were detected after the BS-vaccine treatment, indicating that the monoterpene acylated moiety, absent in the BS vaccine, is not necessary for the induction of a protective global TH1 response. Only the DTH response of BS vaccines was mildly lower than that of CP05 vaccinees. Maximal anti-FML antibody, CD4(+) and CD8(+) Leishmania specific lymphocytes, IFN-gamma splenocyte secretion, reduction in parasite load and survival was also detected for the BS vaccine. The HSFML vaccine showed diminished responses in all tested variables, except for IFN-gamma secretion, indicating that the integrity of the carbohydrate moiety attached to C28 is mandatory for the these functions. No protection was induced by the sapogenin-FML indicating that the CP05 triterpene which lacks the C4 aldehyde group, is not a immunostimulating compound. No contribution to protection was detected in the CP05 saponin treated control group supporting the specificity of the FML antigenic preparation.


Asunto(s)
Fabaceae/química , Leishmaniasis Visceral/prevención & control , Saponinas/química , Saponinas/farmacología , Terpenos/química , Adyuvantes Inmunológicos , Animales , Femenino , Inmunoglobulinas/sangre , Ratones , Estructura Molecular , Relación Estructura-Actividad , Vacunación
18.
Vaccine ; 24(18): 3909-20, 2006 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-16556475

RESUMEN

The adjuvant of the FML-vaccine against murine and canine visceral leishmaniasis, the Riedel de Haen saponin mixture, was fractionated by ion exchange chromatography on DEAE-cellulose to afford one TLC homogeneous Quillaja saponaria Molina QS21 saponin fraction (18.0%), a mixture of two deacylsaponins (19.4%), sucrose (39.9%), sucrose and glucose (19.7%), rutin (0.8%) and quercetin (2.2%), that were identified by comparison of 1H and 13C NMR spectroscopy. The QS21 shows the typical aldehyde group in C-23 (65% equatorial) and a normonoterpene moiety acylated in C-28. The deacylsaponins show the aldehyde group but do not have the normonoterpene moiety. Balb/c mice were vaccinated with 150 microg of FML antigen of Leishmania donovani and 100 microg of each obtained fraction and further challenged by infection with 10(8) amastigotes of Leishmania chagasi. The safety analysis and the effect on humoral and cellular immune responses and in clinical signs showed that the QS21 saponin and the deacylsaponins are the most active adjuvant compounds of the Riedel the Haen saponin mixture. Both induced the highest and non-significantly different increases in DTH, CD4+ T lymphocytes in spleen, IFN-gamma in vitro, body weight gain and the most pronounced reduction of parasite burden in liver (95% for QS21 and 86% for deacylsaponins; p>0.05). While the QS21 showed mild toxicity, significant adjuvant effect on the anti-FML humoral response before and after infection, and decrease in liver relative weight, the deacylsaponins showed no toxicity, less haemolysis and antibody and DTH responses increased mainly after infection, still inducing a stronger Leishmania-specific in vitro splenocyte proliferation. Our results confirm in the Riedel de Haen saponin extract the presence of deacylsaponins normonoterpene-deprivated which are non-toxic and capable of inducing a specific and strong immunoprotective response in vaccination against murine visceral leishmaniasis.


Asunto(s)
Adyuvantes Inmunológicos , Lectinas/inmunología , Leishmania donovani/inmunología , Leishmaniasis Visceral/prevención & control , Vacunas Antiprotozoos/inmunología , Quillaja/química , Saponinas/inmunología , Acilación , Adyuvantes Inmunológicos/administración & dosificación , Animales , Anticuerpos Antiprotozoarios/sangre , Antígenos de Protozoos/administración & dosificación , Antígenos de Protozoos/inmunología , Linfocitos T CD4-Positivos/inmunología , Cromatografía por Intercambio Iónico , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Hemólisis , Hipersensibilidad Tardía , Interferón gamma/biosíntesis , Lectinas/administración & dosificación , Leishmaniasis Visceral/inmunología , Leishmaniasis Visceral/parasitología , Leishmaniasis Visceral/patología , Hígado/parasitología , Hígado/patología , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos BALB C , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/inmunología , Saponinas/administración & dosificación , Saponinas/química , Saponinas/toxicidad , Bazo/inmunología
19.
Neuroimage ; 30(1): 172-83, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16288893

RESUMEN

Human cortical plasticity has been studied after peripheral sensory alterations due to amputations or grafts, while sudden 'quasi-physiological' changes in the dimension of body parts have not been investigated yet. We examined the cortical reorganization in achondroplastic dwarfs submitted to progressive elongation (PE) of lower limbs through the Ilizarov technique. This paradigm is ideal for studying cortical plasticity because it avoids the perturbation connected with deafferentation and re-afferentation. Somatosensory evoked-potentials (SEP) and fMRI studies were performed before and after PE during foot and knee stimulation, above and below the surgical fracture. A body schema test was also performed. Following PE, cortical modifications were observed in the primary somatosensory cortex for foot stimulation and in higher order somatosensory cortices for foot and knee. The former modifications tended to decrease 6 months after the elongation ending, whereas the latter tended to persist. Results are interpreted in terms of cortical adaptation mediated by temporary disorganization.


Asunto(s)
Acondroplasia/cirugía , Técnica de Ilizarov , Músculo Esquelético/inervación , Plasticidad Neuronal/fisiología , Corteza Somatosensorial/fisiología , Tibia/inervación , Tibia/cirugía , Adolescente , Estatura/fisiología , Imagen Corporal , Mapeo Encefálico , Dominancia Cerebral/fisiología , Potenciales Evocados Somatosensoriales/fisiología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Valores de Referencia
20.
AIDS ; 17(8): 1209-16, 2003 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-12819523

RESUMEN

OBJECTIVE: To measure the impact of HIV on mortality in Addis Ababa, Ethiopia. DESIGN: A retrospective review of burials at three cemeteries, 1987-2001 and a prospective surveillance of burials at all (n = 70) cemeteries, February-May, 2001. METHODS: The age, sex, and date of burial were recorded; in the absence of denominators, we compared the ratio of deaths of persons 25-49 versus 5-14 years of age per calendar year, using logistic regression, adjusting for sex and site. The age- and sex- specific mortality were calculated and compared with pre-HIV mortality in 1984. RESULTS: Of 17,519 deaths, retrospectively reviewed, complete data were available for 6342 (47%) females and 7269 (53%) males. During 1987-2001, the '25-49' versus '5-14' group all-cause mortality ratio increased by 8.5% per calendar year (P < 0.05). A total of 5101 deaths were recorded in the prospective surveillance. Crude mortality rates were 9.5/1000 per year (men) and 7.1/1000 per year (women). In comparison with 1984, 5.0-times as many men and 5.3-times as many women died in the age group 35-39 years. Attributing the increase in mortality in ages 15-60 to HIV in the period 1984-2001, Ethiopian men and women have a probability of 18.8 and 17.8%, respectively, of dying of HIV before age 60. CONCLUSION: Burials increased significantly among the '25-49', versus the '5-14' group, during the period 1987-2001. This trend, and a five-times higher mortality in 2001 than in 1984 in those aged 35-39 years demonstrate a severe impact of HIV on mortality. Continuing surveillance of burials is recommended.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/mortalidad , Adolescente , Adulto , Distribución por Edad , Niño , Preescolar , Certificado de Defunción , Etiopía/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Estudios Prospectivos , Estudios Retrospectivos , Distribución por Sexo
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