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1.
J Appl Microbiol ; 131(3): 1261-1273, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33539603

RESUMO

AIMS: The microbial dynamics associated with the decomposition of maize (Zea mays) and coconut (Cocos nucifera) residues were investigated to assess the feasibility of using them as mulch in tropical soils. METHODS AND RESULTS: Phospholipid fatty-acid (PLFA) profiling, microbial biomass (MB-C), basal respiration, C-cycle enzyme activities and inorganic N dynamics were monitored in a microcosm experiment incubating soil samples with plant residues for 425 days. Maize stover (MS) showed a higher decomposition, respiration rate, MB-C, enzymes activities and shift in microbial community structure than coconut husk (CH), which was barely changed. In MS, the lower N level increased C losses and decreased N mineralization compared to the higher N level. CONCLUSIONS: Maize stover is suitable for mulching and has a high potential of increasing soil quality if the proper N fertilization level is used, avoiding excessive C mineralization and N immobilization. Coconut husk decomposition was mostly impaired, indicating that a pre-processing is necessary to improve the benefits of this residue. SIGNIFICANCE AND IMPACT OF THE STUDY: Tropical soils are prone to degradation. Mulching can promote soil conservation, but depends on residue type and soil chemistry. Our study showed that MS managed under the recommended N fertilization level is suitable for mulching while CH is highly inaccessible for microbial degradation.


Assuntos
Cocos , Nitrogênio , Microbiologia do Solo , Solo , Zea mays , Carbono , Fertilização , Nitrogênio/análise
2.
Opt Lett ; 45(21): 6002-6005, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33137054

RESUMO

The quantum analogue of ptychography, a powerful coherent diffractive imaging technique, is a simple method for reconstructing d-dimensional pure states. It relies on measuring partially overlapping parts of the input state in a single orthonormal basis and feeding the outcomes to an iterative phase retrieval algorithm for postprocessing. We provide a proof of concept demonstration of this method by determining pure states given by superpositions of d transverse spatial modes of an optical field. A set of n rank-r projectors, diagonal in the spatial mode basis, is used to generate n partially overlapping parts of the input, and each part is projectively measured in the Fourier transformed basis. For d up to 32, we successfully reconstructed hundreds of random states using n=5 and n=d rank-⌈d/2⌉ projectors. The extension of quantum ptychography for other types of photonic spatial modes is outlined.

3.
Phys Rev Lett ; 118(10): 100501, 2017 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-28339223

RESUMO

Quantum mechanics forbids perfect discrimination among nonorthogonal states through a single shot measurement. To optimize this task, many strategies were devised that later became fundamental tools for quantum information processing. Here, we address the pioneering minimum-error (ME) measurement and give the first experimental demonstration of its application for discriminating nonorthogonal states in high dimensions. Our scheme is designed to distinguish symmetric pure states encoded in the transverse spatial modes of an optical field; the optimal measurement is performed by a projection onto the Fourier transform basis of these modes. For dimensions ranging from D=2 to D=21 and nearly 14 000 states tested, the deviations of the experimental results from the theoretical values range from 0.3% to 3.6% (getting below 2% for the vast majority), thus showing the excellent performance of our scheme. This ME measurement is a building block for high-dimensional implementations of many quantum communication protocols, including probabilistic state discrimination, dense coding with nonmaximal entanglement, and cryptographic schemes.

4.
Int J Obes (Lond) ; 37(9): 1183-91, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23229740

RESUMO

OBJECTIVE: To identify the emotional and motivational processes that reinstate palatable food intake following removal of high-fat diet (HFD) and associated neuroadaptations tied to neurochemical and behavioural changes underlying dopaminergic function. METHODS: Adult male C57Bl6 mice were placed on a HFD (58% kcal fat) or ingredient-matched, low-fat diet (LFD; 11% kcal fat) for 6 weeks. At the end of diet-regimen mice were either maintained on their respective diets, or HFD and LFD were replaced with normal chow (withdrawal). Effort-based operant responding for sucrose and high-fat food rewards was measured along with basal and stress-induced corticosterone levels and anxiety (elevated-plus maze). Protein levels for tyrosine hydroxylase (TH), corticosterone releasing factor type 1 receptor (CRF-R1), brain-derived neurotrophic factor (BDNF), phospho-CREB (pCREB) and ΔFosB (truncated splice variant of FosB) were assessed in the amygdala, nucleus accumbens (NAc) and ventral tegmental area (VTA) via western immunoblotting. RESULTS: Six weeks of HFD resulting in significant weight gain elicited sucrose anhedonia, anxiety-like behaviour and hypothalamic-pituitary-adrenocortical axis (HPA) hypersensitivity to stress. Withdrawal from HFD but not LFD-potentiated anxiety and basal corticosterone levels and enhanced motivation for sucrose and high-fat food rewards. Chronic high-fat feeding reduced CRF-R1 and increased BDNF and pCREB protein levels in the amygdala and reduced TH and increased ΔFosB protein in NAc and VTA. Heightened palatable food reward in mice withdrawn from HFD coincided with increased BDNF protein levels in NAc and decreased TH and pCREB expression in the amygdala. CONCLUSION: Anhedonia, anxiety and sensitivity to stressors develops during the course of HFD and may have a key role in a vicious cycle that perpetuates high-fat feeding and the development of obesity. Removal of HFD enhances stress responses and heightens vulnerability for palatable foods by increasing food-motivated behaviour. Lasting changes in dopamine and plasticity-related signals in reward circuitry may promote negative emotional states, overeating and palatable food relapse.


Assuntos
Ansiedade/metabolismo , Encéfalo/metabolismo , Dieta Hiperlipídica , Obesidade/metabolismo , Estresse Psicológico/metabolismo , Animais , Ansiedade/fisiopatologia , Comportamento Animal , Western Blotting , Encéfalo/fisiopatologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora , Plasticidade Neuronal , Obesidade/etiologia , Obesidade/fisiopatologia , Regiões Promotoras Genéticas , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Recompensa , Estresse Psicológico/fisiopatologia , Sacarose/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
5.
J Periodontal Res ; 48(5): 632-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23425324

RESUMO

BACKGROUND AND OBJECTIVE: Recent evidence suggests that the use of fluoxetine could reduce periodontal disease severity. However, the effect of fluoxetine on periodontal disease has not been tested in the context of conditioned fear stress (CFS). We hypothesized that inhibition of chronic stress by fluoxetine might decrease the levels of bone loss in periodontal disease. The aim of the present study was to analyze the effect of fluoxetine on bone loss in chronic periodontitis. MATERIAL AND METHODS: Fourteen Wistar rats were submitted to ligature-induced periodontal disease and divided into four groups (A-D). Groups A (n = 3) and B (n = 4) were not stressed, while Groups C (n = 3) and D (n = 4) were submitted to a CFS paradigm for 38 d. Daily fluoxetine (20 mg/kg) was administered to Groups B and D from day 20 to day 39, at which point the rats were submitted to an open field test and killed on day 40. Mandibles were removed for histological and immunohistochemical analyses. RESULTS: Stress was associated with a higher level of bone loss in Group C compared with Group A. Additionally, no differences in bone loss were observed among Groups A, B and D. CONCLUSION: We showed that stress is associated with the progression of bone loss in a CFS model in rats and that fluoxetine treatment reduces the bone loss.


Assuntos
Periodontite Crônica/prevenção & controle , Medo/psicologia , Fluoxetina/uso terapêutico , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Estresse Psicológico/psicologia , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/prevenção & controle , Perda do Osso Alveolar/psicologia , Animais , Ansiedade/psicologia , Periodontite Crônica/patologia , Periodontite Crônica/psicologia , Condicionamento Psicológico , Modelos Animais de Doenças , Progressão da Doença , Reação de Congelamento Cataléptica/fisiologia , Interleucina-1beta/análise , Interleucina-6/análise , Locomoção/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar
6.
Neotrop Entomol ; 48(1): 171-174, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30632083

RESUMO

The lethal yellowing (LY) is a major phytoplasma causing disease seriously threatening coconut plantations worldwide, with imminent risk of entering Brazil. The LY phytoplasma is restricted to the phloem and transmitted by the planthopper Haplaxius crudus (Van Duzee) (Cixiidae). In this study, Auchenorrhyncha were collected on the leaves of Dwarf vs. Dwarf hybrids and Brazilian Green Dwarf Jiqui in the Brazilian northern state of Para using yellow adhesive traps in May of 2016. The planthopper H. crudus was found in coconut plantations of Brazilian Green Dwarf Jiqui, accounting for 87% of the individuals captured. This is the first report of vector H. crudus in Brazilian coconut plantations. These findings are of great scientific relevance since H. crudus could negatively impact the Brazilian coconut industry and this knowledge could be used in contingency measures in the case of LY be introduced in the country.


Assuntos
Cocos , Hemípteros , Animais , Brasil , Insetos Vetores , Phytoplasma , Doenças das Plantas/microbiologia , Folhas de Planta
8.
J Eur Acad Dermatol Venereol ; 21(10): 1351-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17958841

RESUMO

BACKGROUND: The patch test is an essential procedure for the investigation of aetiologic diagnosis of allergic contact dermatitis, although it is not yet able to fully reproduce the events of the initial site of contact with the allergen. OBJECTIVES: The aims of the present study are (i) to assess whether removal of the superficial corneous layer results in test positivity differences vs. the traditional technique, (ii) to assess the probable and/or possible and past and/or present sensitivity and relevance for each method, and (iii) to compare specific relevance of nickel sulphate for each method. RESULTS: Concordance of positive reactions was 75.9% (66 of 87), with 21.8% (19 of 87) positivity results on the abraded side only and 2.3% (2 of 87) on the unabraded side (P < 0.05). Concordance of the substances with probable and/or possible and past and/or present relevance was 77.3% (58 of 75) for the abraded side and 21.3% (16 of 75) and 1.3% (1 of 75) for the unabraded side (P < 0.05). Analysis of isolated relevance for nickel sulphate showed 95.6% (22 of 23) concordance. CONCLUSIONS: (i) We found a greater number of positive substances on the abraded side, and when only the 2 + and 3 + reactions were considered, greater relative discordance was also observed; (ii) relevance analysis revealed a statistically significant difference between the two methods; (iii) differences in nickel sulphate test positivity and relevance for the two methods did not reach statistical significance.


Assuntos
Dermatite de Contato/diagnóstico , Testes do Emplastro/métodos , Adolescente , Adulto , Idoso , Distribuição de Qui-Quadrado , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Fita Cirúrgica
9.
Br J Neurosurg ; 16(1): 16-20, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11926460

RESUMO

The objective of the investigation was to report on the health-related quality of life (HRQoL) of patients diagnosed with skull base tumours using the Short Form Health Survey questionnaire (SF-36). Those patients suffering with vestibular schwannoma were examined to determine the effect facial nerve function had on their quality of life. It took place at the tertiary referral centre at the Department of Clinical Neurosciences, Western General Hospital, Edinburgh. A prospective study of 70 consecutive patients was taken, who harboured the following tumours: 54 vestibular schwannomas, 13 meningiomas, two haemangioblastomas and one hypoglossal schwannoma. Patients were interviewed using the short form 36 (SF-36) questionnaire. Facial nerve function was assessed in those patients who had vestibular schwannomas. The entire cohort of live skull base patients were assessed after a median follow-up time of 38.4 months. Patients with vestibular schwannoma treated conservatively with interval MRI had a quality of life similar to t he normal population. Those who underwent surgery had a significant difference in two of the SF-36 domains. No statistically significant correlation was found at final assessment between the degree of facial nerve functioning and any of the domains of SF-36. Patients with non-vestibular tumours had an impaired HRQoL in seven of the eight domains. Patients with skull base tumours have a significant impairment of their HRQoL. A conservative policy of follow up with interval MRI for patients with small vestibular schwannomas may therefore be more appropriate to preserve their HRQoL. Facial nerve outcome has little influence on quality of life in vestibular schwannoma patients.


Assuntos
Qualidade de Vida , Perfil de Impacto da Doença , Neoplasias da Base do Crânio/reabilitação , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neuroma Acústico/patologia , Neuroma Acústico/reabilitação , Neuroma Acústico/cirurgia , Estudos Prospectivos , Escócia , Neoplasias da Base do Crânio/cirurgia , Inquéritos e Questionários , Resultado do Tratamento
10.
J Eur Acad Dermatol Venereol ; 16(6): 634-7, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12482053

RESUMO

We report a case of acute generalized exanthematous pustulosis (AGEP) in a 64-year-old woman, associated with the use of bamifylline. To the best of our knowledge there have been no previous reports of AGEP induced by the ingestion of bamifylline in the medical literature. We, therefore, add this drug to the list of causes for AGEP.


Assuntos
Broncodilatadores/efeitos adversos , Toxidermias/etiologia , Exantema/induzido quimicamente , Dermatopatias Vesiculobolhosas/induzido quimicamente , Teofilina/análogos & derivados , Teofilina/efeitos adversos , Asma/tratamento farmacológico , Broncodilatadores/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Teofilina/uso terapêutico
11.
Union Med Can ; 122(2): 103-8, 1993.
Artigo em Francês | MEDLINE | ID: mdl-8493737

RESUMO

The prevalence of antineutrophil cytoplasmic antibodies (ANCAs) was verified in 338 patients with various rheumatic diseases using the internationally standardized indirect immunofluorescence method. The method was improved by using ethidium bromide as a nuclear counterstain. We observed three patterns of fluorescence: the classical diffuse cytoplasmic granular staining (C); the perinuclear one (P) and a yet undescribed atypical cytoplasmic distribution (A). We thus found ANCAs in 14/15 (93%) patients with active Wegener's granulomatosis: 13 were C-ANCAs, 1 was P-ANCA. We also found ANCAs in 6/25 (22%) patients with other systemis vasculitides (essentially those with small vessel vasculitis): they were C-ANCAs (3 cases) or P-ANCAs (3 cases). Finally, ANCAs were detected in 10/185 patients with various autoimmune diseases (5 with rheumatoid arthritis and 5 with systemic lupus erythematosus): they were C-ANCAs (1 case), P-ANCAs (4 cases) or A-ANCAs (5 cases). No ANCAs were found in 100 control patients with miscellaneous diseases. The isotype distribution of ANCAs is essentially limited to IgG classes and the serum titre usually reflects disease activity. The technical improvement facilitates the distinction of ANCAs from other antinuclear and anticytoplasmic autoantibodies found in connective tissue diseases. Our data emphasize the clinical importance of ANCA detection and justify our efforts to develop more specific and quantitative assays.


Assuntos
Autoanticorpos/sangue , Imunoglobulina G/sangue , Doenças Reumáticas/sangue , Anticorpos Anticitoplasma de Neutrófilos , Autoanticorpos/classificação , Estudos de Avaliação como Assunto , Imunofluorescência/normas , Humanos , Imunoglobulina G/classificação , Prevalência , Doenças Reumáticas/classificação , Doenças Reumáticas/epidemiologia , Sensibilidade e Especificidade
12.
J Rheumatol ; 18(9): 1359-63, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1836814

RESUMO

99mTc-pyrophosphate musculoskeletal imaging and 99mTc-red blood cell gated blood pool imaging were performed on 10 patients with documented polymyositis/dermatomyositis. Abnormal 99mTc-pyrophosphate uptake by peripheral muscles was found in 8 patients (6 mild, 2 marked). Cardiac uptake occurred in 5 patients and was 3+ in 2 with cardiovascular symptoms. These 2 patients also had abnormal EF on gated blood pool imaging. Patients without myocardial 99mTc-pyrophosphate uptake had normal EF. Patients with myocardial 99mTc-pyrophosphate uptake had abnormal wall motion, in proportion to the degree of uptake. Response to therapy and outcome were poorer in patients with marked scintigraphic changes. These findings suggest that the magnitude of 99mTc-pyrophosphate myocardial uptake may have prognostic implications in these patients.


Assuntos
Cardiomiopatias/fisiopatologia , Dermatomiosite/fisiopatologia , Coração/fisiopatologia , Miosite/fisiopatologia , Músculos Papilares/fisiopatologia , Adolescente , Adulto , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/patologia , Criança , Dermatomiosite/diagnóstico , Dermatomiosite/patologia , Feminino , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Sistema Musculoesquelético/diagnóstico por imagem , Sistema Musculoesquelético/metabolismo , Miosite/diagnóstico , Miosite/patologia , Músculos Papilares/diagnóstico por imagem , Músculos Papilares/patologia , Cintilografia , Pirofosfato de Tecnécio Tc 99m
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