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1.
Inorg Chem ; 61(48): 19248-19260, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36403154

RESUMO

The introduction of defects is one of the most recurrent pathways to generate modifications to materials' electronic structure and surface reactivity. In this work, calculations based on the density functional theory (DFT) were applied to study the electronic properties of pristine and reduced TiO2(B)(100) ultrathin sheets to evaluate their potential as a semiconductor material for dye-sensitized solar cells (DSSCs). It was carried out by introducing vacancy defects on these surfaces and then adsorbing a catechol molecule, used as a model of a direct electron injection sensitizer (type-II dye), in different interaction configurations. Geometric, energetic, and electronic analyses were performed, focusing on the electronic structure changes and charge transfer between the dye and surface during molecular adsorption. The obtained results seem to indicate that a thickness of four layers is adequate to obtain a satisfactory slab model approximation of the TiO2(B)(100) surface. The presence of oxygen vacancy states among the majority of the reduced surfaces was observed as well as a reduction of the band gap energy value. Additionally, the adsorption of catechol in the reduced surface induced an increase in light absorption compared to the pristine model. These attributes suggest that reduced ultrathin sheets of TiO2(B) could be a suitable candidate as a photoelectrode for DSSC applications.

2.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 35(7): 441-443, ago.-sept. 2017. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-165242

RESUMO

Recientemente hemos documentado un caso de paraparesia espástica tropical por HTLV-I en un paciente de nacionalidad española. Este retrovirus infrecuente en Europa rara vez produce sintomatología, pero cuando lo hace supone un grave problema sanitario. Aquí presentamos dicho caso y discutimos situaciones clínicas que justifiquen su detección. Se analizaron las peticiones de cribado de HTLV que recibimos durante 2014-2015 (n=123). El algoritmo diagnóstico fue: 1) Enzimoinmunoanálisis, 2) Hibridación reversa y 3) PCR de ADN proviral. Los resultados mostraron diversas situaciones de cribado de HTLV, destacando el estudio de paraparesia (22%). Se detectaron 7 casos de infección por HTLV-I: 5 pacientes de zona endémica, un paciente VIH+ y por último el caso de paraparesia mencionado. La vigilancia de HTLV-I en regiones no endémicas supone un reto sanitario al no estar bien establecido su balance coste-beneficio. Este caso apoya la inclusión de HTLV-I dentro del diagnóstico diferencial de paraparesia espástica de evolución insidiosa (AU)


We have recently documented a case of tropical spastic paraparesis by HTLV-I in a Spanish patient. HTLV-I infection is rare in Europe, and hardly ever is accompanied by symptoms, but if it does it could trigger a major health issue. This case is presented here, as well as a discussion on the situations in which HTLV-I detection is justified. An analysis was made of the HTLV diagnostic requests at our centre during 2014-2015 (n=123). The diagnostic algorithm was: 1) Enzyme immunoassay, 2) Reverse hybridization, and 3) Proviral DNA detection by PCR. The results showed several situations of HTLV screening, emphasising those related to paraparesis (22%). Seven cases of HTLV-I infection were found: five in patients from endemic regions, one in an HIV-infected patient, and the case of TSP mentioned above. HTLV-I surveillance in non-endemic regions is a challenging issue, as the cost-benefit ratio is not well-established. This case report emphasises the importance of including HTLV within the differential diagnosis of insidious spastic paraparesis (AU)


Assuntos
Humanos , Masculino , Adulto , Paraparesia Espástica Tropical/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Infecções por HTLV-I/microbiologia , Programas de Rastreamento/métodos
3.
Enferm Infecc Microbiol Clin ; 35(7): 441-443, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26282070

RESUMO

We have recently documented a case of tropical spastic paraparesis by HTLV-I in a Spanish patient. HTLV-I infection is rare in Europe, and hardly ever is accompanied by symptoms, but if it does it could trigger a major health issue. This case is presented here, as well as a discussion on the situations in which HTLV-I detection is justified. An analysis was made of the HTLV diagnostic requests at our centre during 2014-2015 (n=123). The diagnostic algorithm was: 1) Enzyme immunoassay, 2) Reverse hybridization, and 3) Proviral DNA detection by PCR. The results showed several situations of HTLV screening, emphasising those related to paraparesis (22%). Seven cases of HTLV-I infection were found: five in patients from endemic regions, one in an HIV-infected patient, and the case of TSP mentioned above. HTLV-I surveillance in non-endemic regions is a challenging issue, as the cost-benefit ratio is not well-established. This case report emphasises the importance of including HTLV within the differential diagnosis of insidious spastic paraparesis.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Paraparesia Espástica Tropical/diagnóstico , Paraparesia Espástica Tropical/virologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espanha
4.
Med Oral Patol Oral Cir Bucal ; 17(5): e893-901, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22549681

RESUMO

OBJECTIVES: To explore peri-implant health (and relation with periodontal status) 4-5 years after implant insertion. STUDY DESIGN: A practice-based dental research network multicentre study was performed in 11 Spanish centres. The first patient/month with implant insertion in 2004 was considered. Per patient four teeth (one per quadrant) showing the highest bone loss in the 2004 panoramic X-ray were selected for periodontal status assessment. Bone losses in implants were calculated as the differences between 2004 and 2009 bone levels in radiographs. RESULTS: A total of 117 patients were included. Of the 408 teeth considered, 73 (17.9%) were lost in 2009 (losing risk: >50% for bone losses ≥7 mm). A total of 295 implants were reviewed. Eight of 117 (6.8%) patients had lost implants (13 of 295 implants installed; 4.4%). Implant loss rate (quadrant status) was 1.4% (edentulous), 3.6% (preserved teeth), and 11.1% (lost teeth) (p=0.037). The percentage of implant loss significantly (p<0.001) increased when the medial/distal bone loss was ≥3 mm. The highest (p≤0.001) pocket depths were found in teeth with ≥5 mm and implants with ≥3 mm bone losses, with similar mean values (≥4 mm), associated with higher rates of plaque index and bleeding by probing. CONCLUSIONS: The significant bi-directional relation between plaque and bone loss, and between each of these two parameters/signs and pocket depths or bleeding (both in teeth and implants, and between them) together with the higher percentage of implants lost when the bone loss of the associated teeth was ≥3 mm suggest that the patient's periodontal status is a critical issue in predicting implant health/lesion.


Assuntos
Implantes Dentários , Saúde Bucal , Pesquisa Biomédica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peri-Implantite/diagnóstico , Peri-Implantite/epidemiologia , Índice Periodontal , Periodontite/diagnóstico , Periodontite/epidemiologia , Espanha , Fatores de Tempo
5.
Neurotox Res ; 4(5-6): 437-451, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12754158

RESUMO

The interpretation of the huge number of results in schizophrenia research using neuroimaging is uncertain. However, the simultaneous use of complimentary data obtained with these techniques may yield more relevant information in this regard. In this paper we present a series of studies performed by our group in two schizophrenic samples with the use of structural (magnetic resonance imaging, MRI), functional [glucose positron emission tomography (PET) and N-acetyl-aspartate (NAA) magnetic resonance spectrocopy] and neurophysiological techniques (the P300 event-related potential). Transversal and longitudinal measurements were performed.The integrated vision of the results so obtained allows us to propose the hypothesis of a neurodevelopmentally determined state of prefrontal disinihibition, in which the degree of atrophy would directly relate to the metabolic rate. This state would already be present in the first stages of illness and could have neurotoxic consequences in the long term. This would explain the findings of an association between sulcal cerebrospinal fluid (CSF) and illness duration and decreased NAA levels in chronic but not in recent-onset cases. The prefrotnal disinhibition would overstimulate the limbic system and the hippocampus would become overactivated, the metabolic rate at this level being inversely related to P300 amplitude. Clozapine showed a more selective and intense action on that hyperactive metabolic tone than haloperidol.

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