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2.
Ecology ; 103(4): e3640, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35060633

RESUMO

Data papers and open databases have revolutionized contemporary science, as they provide the long-needed incentive to collaborate in large international teams and make natural history information widely available. Nevertheless, most data papers have focused on species occurrence or abundance, whereas interactions have received much less attention. To help fill this gap, we have compiled a georeferenced data set of interactions between 93 bat species of the family Phyllostomidae (Chiroptera) and 501 plant species of 68 families. Data came from 169 studies published between 1957 and 2007 covering the entire Neotropical Region, with most records from Brazil (34.5% of all study sites), Costa Rica (16%), and Mexico (14%). Our data set includes 2571 records of frugivory (75.1% of all records) and nectarivory (24.9%). The best represented bat genera are Artibeus (28% of all records), Carollia (24%), Sturnira (10.1%), and Glossophaga (8.8%). Carollia perspicillata (187), Artibeus lituratus (125), Artibeus jamaicensis (94), Glossophaga soricina (86), and Artibeus planirostris (74) were the bat species with the broadest diets recorded based on the number of plant species. Among the plants, the best represented families were Moraceae (17%), Piperaceae (15.4%), Urticaceae (9.2%), and Solanaceae (9%). Plants of the genera Cecropia (46), Ficus (42), Piper (40), Solanum (31), and Vismia (27) exhibited the largest number of interactions. These data are stored as arrays (records, sites, and studies) organized by logical keys and rich metadata, which helped to compile the information on different ecological and geographic scales, according to how they should be used. Our data set on bat-plant interactions is by far the most extensive, both in geographic and taxonomic terms, and includes abiotic information of study sites, as well as ecological information of plants and bats. It has already facilitated several studies and we hope it will stimulate novel analyses and syntheses, in addition to pointing out important gaps in knowledge. Data are provided under the Creative Commons Attribution 4.0 International License. Please cite this paper when the data are used in any kind of publication related to research, outreach, and teaching activities.


Assuntos
Quirópteros , Ficus , Piper , Animais , Brasil , Costa Rica , Humanos
3.
Nat Commun ; 11(1): 3215, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32587246

RESUMO

Changes in global and regional precipitation regimes are among the most pervasive components of climate change. Intensification of rainfall cycles, ranging from frequent downpours to severe droughts, could cause widespread, but largely unknown, alterations to trophic structure and ecosystem function. We conducted multi-site coordinated experiments to show how variation in the quantity and evenness of rainfall modulates trophic structure in 210 natural freshwater microcosms (tank bromeliads) across Central and South America (18°N to 29°S). The biomass of smaller organisms (detritivores) was higher under more stable hydrological conditions. Conversely, the biomass of predators was highest when rainfall was uneven, resulting in top-heavy biomass pyramids. These results illustrate how extremes of precipitation, resulting in localized droughts or flooding, can erode the base of freshwater food webs, with negative implications for the stability of trophic dynamics.


Assuntos
Bromelia , Ecossistema , Inundações , Água Doce , Animais , Biodiversidade , Biomassa , Mudança Climática , Secas , Cadeia Alimentar , Hidrologia , América do Sul
4.
Ecology ; 101(4): e02984, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31958151

RESUMO

There is growing recognition that ecosystems may be more impacted by infrequent extreme climatic events than by changes in mean climatic conditions. This has led to calls for experiments that explore the sensitivity of ecosystems over broad ranges of climatic parameter space. However, because such response surface experiments have so far been limited in geographic and biological scope, it is not clear if differences between studies reflect geographic location or the ecosystem component considered. In this study, we manipulated rainfall entering tank bromeliads in seven sites across the Neotropics, and characterized the response of the aquatic ecosystem in terms of invertebrate functional composition, biological stocks (total invertebrate biomass, bacterial density) and ecosystem fluxes (decomposition, carbon, nitrogen). Of these response types, invertebrate functional composition was the most sensitive, even though, in some sites, the species pool had a high proportion of drought-tolerant families. Total invertebrate biomass was universally insensitive to rainfall change because of statistical averaging of divergent responses between functional groups. The response of invertebrate functional composition to rain differed between geographical locations because (1) the effect of rainfall on bromeliad hydrology differed between sites, and invertebrates directly experience hydrology not rainfall and (2) the taxonomic composition of some functional groups differed between sites, and families differed in their response to bromeliad hydrology. These findings suggest that it will be difficult to establish thresholds of "safe ecosystem functioning" when ecosystem components differ in their sensitivity to climatic variables, and such thresholds may not be broadly applicable over geographic space. In particular, ecological forecast horizons for climate change may be spatially restricted in systems where habitat properties mediate climatic impacts, and those, like the tropics, with high spatial turnover in species composition.


Assuntos
Mudança Climática , Ecossistema , Animais , Secas , Invertebrados , Chuva
5.
Int J Pharm ; 562: 86-95, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30885651

RESUMO

Coumestrol is a polyphenol with promising therapeutic applications as phytoestrogen, antioxidant and potential cancer chemoprevention agent. The presence of two hydroxyl groups on its chemical structure, with orientation analogous to estradiol, is responsible of both, its antioxidant capacity and its estrogenic activity. However, several studies show that the interaction of polyphenols with food and plasma proteins reduces their antioxidant efficacy. We studied the interaction of coumestrol with bovine serum albumin protein (BSA) by fluorescence spectroscopy and circular dichroism techniques, and the effect of this interaction on its antioxidant activity as a hydroxyl radical scavenger. In addition, coumestrol antioxidant capacity profile using different assays (DPPH, ORAC-FL and ORAC-EPR) was studied. To explain its reactivity we used several methodologies, including DFT calculations, to define its antioxidant mechanism. Coumestrol antioxidant activity unveiled interesting antioxidant properties. BSA interaction with coumestrol reduces significantly photolytic degradation in several media thus preserving its antioxidant properties. Results suggest no significant changes in BSA structure and activity when interacting with coumestrol. Furthermore, this interaction is stronger than for other phytoestrogens such as daidzein and genistein. Considering our promising results, we reported for the first time the fabrication and characterization of coumestrol-loaded albumin nanoparticles. The resulting spherical and homogeneous nanoparticles showed a diameter close to 96 nm. The coumestrol incorporation efficiency in BSA NPs was 22.4%, which is equivalent to 3 molecules of coumestrol for every 10 molecules of BSA.


Assuntos
Antioxidantes/química , Cumestrol/química , Portadores de Fármacos/química , Nanopartículas/química , Fitoestrógenos/química , Soroalbumina Bovina/química , Radical Hidroxila/química
6.
J AOAC Int ; 101(1): 235-241, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28766479

RESUMO

In this work, we developed an HPLC method to simultaneously quantify and hence evaluate the stability, distribution, and antioxidant capacity of six isoflavones: genistein, genistin, daidzein, daidzin, glycitin, and biochanin A. Isoflavones have been described as having an important estrogenic activity to treat menopausal symptoms and can reduce postmenopausal bone loss and also participate in the prevention of cardiovascular diseases. These beneficial properties are believed derived from their capacity to act as free-radical scavengers. Isoflavones are formulated in capsules and creams and also can be used as antioxidants in liposomes. HPLC separation was achieved on an Agilent Hypersil ODS C18 column. The mobile phase consisted of 0.02-0.2% orthophosphoric acid in water-acetonitrile with gradient elution. The diode array detector was operated at 260 nm. The hydrophobicity of isoflavones was determined through their distribution in octanol-buffer. These results allowed us to establish a relation between chemical structure, pKa, lipophilicity, and the characteristics of the dispersion medium. Photolysis of hydrogen peroxide was used to measure the HO• scavenging capability of isoflavones. In liposomes, the order of reactivity of the studied compounds was genistein > biochanin A > genistin > daidzein > daidzin > glycitin.


Assuntos
Antioxidantes/análise , Sequestradores de Radicais Livres/análise , Isoflavonas/análise , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Sequestradores de Radicais Livres/farmacologia , Peróxido de Hidrogênio/antagonistas & inibidores , Radical Hidroxila/química , Isoflavonas/farmacologia , Lipossomos/antagonistas & inibidores , Estrutura Molecular , Fotólise , Fatores de Tempo
7.
Psychoanal Study Child ; 62: 329-58, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18524098

RESUMO

The intent of this paper is to add to the psychoanalytic understanding of midlife by exploring the relationships among transience, uncertainty and time limitation; and their effect on intra-psychic conflict and change. After a presentation of definitions and relevant midlife development tasks, the focus shifts to a discussion of two of Freud's papers, "On Transience" (1916 [1915]) and "The Uncanny" (1919) in which Freud introduced important concepts that provide a foundation for psychoanalytic exploration of attitudes toward transience, uncertainty and death. A major focus of the paper is a conceptualization of a developmental continuum from midlife transition to midlife crisis, rather than dichotomizing the midlife developmental process as either transition or crisis, followed by a discussion of three basic ways of processing the continuum and six common ways in which midlife pathology and/or more normative developmental progression are expressed. Two detailed, clinical examples illustrate the theoretical concepts and focus, in particular on clinical presentation and transference and counter-transference. The intention is to link theory with clinical understanding and technique.


Assuntos
Conflito Psicológico , Desenvolvimento da Personalidade , Psicanálise/história , Interpretação Psicanalítica , Adulto , Áustria , História do Século XIX , História do Século XX , Humanos , Pessoa de Meia-Idade
8.
PLoS One ; 10(6): e0129749, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26098745

RESUMO

In this work, the relationship between the molecular structure of three flavonoids (kaempferol, quercetin and morin), their relative location in microheterogeneous media (liposomes and erythrocyte membranes) and their reactivity against singlet oxygen was studied. The changes observed in membrane fluidity induced by the presence of these flavonoids and the influence of their lipophilicity/hydrophilicity on the antioxidant activity in lipid membranes were evaluated by means of fluorescent probes such as Laurdan and diphenylhexatriene (DPH). The small differences observed for the value of generalized polarization of Laurdan (GP) curves in function of the concentration of flavonoids, indicate that these three compounds promote similar alterations in liposomes and erythrocyte membranes. In addition, these compounds do not produce changes in fluorescence anisotropy of DPH, discarding their location in deeper regions of the lipid bilayer. The determined chemical reactivity sequence is similar in all the studied media (kaempferol < quercetin < morin). Morin is approximately 10 times more reactive than quercetin and 20 to 30 times greater than kaempferol, depending on the medium.


Assuntos
Flavonoides/química , Sequestradores de Radicais Livres/química , Oxigênio Singlete/química , Flavonoides/farmacologia , Sequestradores de Radicais Livres/farmacologia , Lipossomos/química
9.
Radiother Oncol ; 67(3): 303-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12865178

RESUMO

PURPOSE: To report post-brachytherapy results in high and intermediate risk patients of prostatic adenocarcinoma. METHODS AND MATERIALS: From June 1994 to June 2000, 356 consecutive high and intermediate risk patients were treated with three-dimensional computed tomography-guided stereotactic pararectal brachytherapy. The age was 42-90 years (median, 68 years), the initial prostate volume was 14-180 cm3 (median, 59 cm3), and initial PSA was 1.7-143 ng/ml (median, 10.5 ng/ml). Three hundred forty-eight patients were available for follow-up for 2-8 years (median, 4.5 years). Two hundred eighty patients had one or more high risk factors (PSA >20 ng/ml, Gleason>7, Stage T2b, T3a, or T3b). Sixty-eight patients had only one intermediate risk factor (PSA 10-20 ng/ml or Gleason=7). Patients with both intermediate risks were considered high risk. The high-risk group was further stratified into subgroups with similar risk profile. A dose of 144 Gy with 125I or 120 Gy with 103Pd was achieved in 90-100% of the target. Thirty (30) patients (9%) had prior transurethral resection and 229 (64%) were treated with 3 months neoadjuvant androgen ablation. RESULTS: Biochemical disease-free survival was 92% of 280 high risk patients and 96% of 68 intermediate risk patients. Seven patients (2%) required catheterization during the first year for urinary retention, nine patients (3%) required TUR 1-3 years post-implant, three patients (1%) developed grade 1 or 2 incontinence after a second TUR, and four patients (1%) developed grade 3 rectal complications. CONCLUSION: This method produces a high level of biochemical control 2-8 years (median 4.5 years). Morbidity is acceptable regardless of risk profile or initial prostate volume.


Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Intervalo Livre de Doença , Seguimentos , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Tomografia Computadorizada por Raios X/métodos , Transtornos Urinários/etiologia
10.
Technol Cancer Res Treat ; 2(4): 339-44, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12892517

RESUMO

Thirty-one [31] patients with local recurrent or residual adenocarcinoma of the prostate, with no evidence of distant metastases, were treated with second permanent implant using a stereotactic three dimensional system and posterior pararectal CT-guided method. All patients had extensive under local anesthesia or IV sedation pararectal CT-guided biopsy of the prostate and seminal vesicles. All patients except one had 3 month neoadjuvant androgen ablation prior to salvage reimplantation. Twenty [20] of these patients had local recurrence in the prostate and eleven [11] patients had seminal vesicle invasion which was not diagnosed nor treated with the initial brachytherapy. In addition, the patients had PSA failure or local palpable disease, "cold spots" with CT imaging or areas of dosage less than 80% of the prescribed dose with DVH (dose volume histogram). Initial prescribed dose was 120 Gy with (103)Pd loose seeds in 26 patients and 144 Gy with (125)I loose seeds in 5 patients. For the reimplant the dosage in the recurrent site was 100-144 Gy with (125)I seeds in strand in 24 patients (77%) and 100-120 Gy with (103)Pd loose seeds in 7 patients (23%). The preference of (125)I seeds in the second treatment was because only (125)I in strand was available at the time of the reimplant. Eleven [11] patients had second implant twelve to twenty-four months after the initial implant and 20 patients had after twenty-five to eighty-seven months and median follow-up was thirty months. A high level of biochemical control (87%) was achieved in all of these patients who are recognized as high risk due to local recurrence. Four [4] patients experienced grade 2 or 3 GI or GU complications and two [2] patients experienced grade 4 GI complications. Patients with local recurrent prostate cancer following initial brachytherapy including those with seminal vesicle invasion can be successfully treated with pararectal stereotactic CT-guided reimplantation. Assessment of seminal vesicle status is an essential part of staging for local recurrence.


Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Terapia de Salvação/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Humanos , Imageamento Tridimensional , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Paládio/uso terapêutico , Radioisótopos/uso terapêutico , Recidiva , Fatores de Tempo
11.
Rev Gastroenterol Peru ; 20(3): 291-295, 2000.
Artigo em Espanhol | MEDLINE | ID: mdl-12140590

RESUMO

A case of a 50-years old female patient with a clinical picture of acute pancratitis caused by gallstone disease is reported. On the evolution she presented bowel obstruction signs. After wards a gallstone by rectum was eliminated with symptoms resolution.A review of the medical literature is done.

14.
J Urol ; 169(4): 1331-6, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12629354

RESUMO

PURPOSE: We report post-brachytherapy results in patients with cancer in a large prostate. MATERIALS AND METHODS: From June 1, 1994 to June 30, 2000, 331 consecutive patients with a large prostate of 50 to 180 cm.3 (median 69) were treated with 3-dimensional computerized tomography guided brachytherapy. Patient age was 42 to 90 years (median 69). Of these patients 327 were available for followup for 2 to 8 years (median 4.5). Patients were stratified according to risk profile. The high risk group had 1 or more high risk factors (prostate specific antigen [PSA] greater than 20 ng./ml., Gleason greater than 7, stage T2b, T3a or T3b) or 2 intermediate risk factors (PSA 10 to 20 ng./ml. and Gleason 7). The high risk group was further stratified into subgroups with a similar risk profile. The intermediate risk group had only 1 high risk factor (PSA 10 to 20 ng./ml. or Gleason 7). The low risk group had PSA less than 10 ng./ml., Gleason less than 7 and stage T1a, b, c or T2a. A dose of 144 Gy. with 125I or 120 Gy. with 103Pd was achieved in 90% to 100% of the target. A total of 31 patients (9%) had previously undergone transurethral resection and 198 (60%) were treated with 3 months of neoadjuvant androgen ablation. RESULTS: Biochemical disease-free survival was achieved in 90% of the 182 patients at high risk, 96% of the 52 at intermediate risk and 99% of the 93 at low risk. Seven patients (2%) required catheterization during year 1 for urinary retention, 11 (3%) required transurethral prostate resection 1 to 4 years after implantation, 3 patients (1%) had grade 1 or 2 incontinence after repeat transurethral prostate resection and 4 (1%) had grade 3 or 4 rectal complications. CONCLUSIONS: The 3-dimensional computerized tomography guided pararectal permanent implant results in a high level of biochemical control with low morbidity at 2 to 8 years in patients with prostate cancer who have a large prostate. There was less favorable biochemical control in patients with PSA greater than 20 ng./ml., Gleason 7 or greater and seminal vesicle invasion.


Assuntos
Braquiterapia/métodos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Terapia Combinada , Intervalo Livre de Doença , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Próstata/diagnóstico por imagem , Próstata/patologia , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Radioterapia Adjuvante , Fatores de Risco , Ressecção Transuretral da Próstata
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