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1.
Talanta ; 269: 125406, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008024

RESUMO

Understanding the role of non-structural carbohydrates (NSC) in tree-level carbon cycling crucially depends on the availability of NSC data in a sufficient temporal resolution covering extreme conditions and seasonal peaks or declines. Chemical analytical methods should therefore get complemented by less extensive retrieval methods. To this end, we explored the potential of diffuse reflectance spectroscopy for estimating NSC contents at a set of 180 samples taken from leaves, roots, stems and branches of different tree species in different biogeographic regions. Multiple randomized partitioning in calibration and validation data were performed with near-infrared (NIR) and mid-infrared (MIR) as well as combined data. With derivative spectra, NIR markedly outperformed MIR data for NSC estimation; mean RMSE for outer validation samples equalled 2.58 (in % of dry matter) compared to 2.90, r2 was 0.64 compared to 0.52. We found complementary information related to NSC in both spectral domains, so that a combination with high-level data fusion (model averaging) increased accuracy (RMSE decreased to 2.19, r2 equalled 0.72). Spectral variable selection with the CARS algorithm further improved results slightly (RMSE = 1.97, r2 = 0.78). On the level of tissue types, we found a marked differentiation concerning the appropriateness of datasets and approaches. High-level data fusion was successful for leaves, NIR data (together with CARS) provided the best results for wooden tissues. This suggests further studies with a greater number of samples per tissue type but only for selected (main) tree species to finally judge the sensitivities of diffuse reflectance spectroscopy (NIR, MIR) for NSC retrieval.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Árvores , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Calibragem , Carbono , Algoritmos , Análise dos Mínimos Quadrados
2.
J Fungi (Basel) ; 9(9)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37755027

RESUMO

Glycoside hydrolases (GHs) are enzymes that participate in many biological processes of fungi and other organisms by hydrolyzing glycosidic linkages in glycosides. They play fundamental roles in the degradation of carbohydrates and the assembly of glycoproteins and are important subjects of studies in molecular biology and biochemistry. Based on amino acid sequence similarities and 3-dimensional structures in the carbohydrate-active enzyme (CAZy), they have been classified in 171 families. Members of some of these families also exhibit the activity of trans-glycosydase or glycosyl transferase (GT), i.e., they create a new glycosidic bond in a substrate instead of breaking it. Fungal glycosidases are important for virulence by aiding tissue adhesion and colonization, nutrition, immune evasion, biofilm formation, toxin release, and antibiotic resistance. Here, we review fungal glycosidases with a particular emphasis on Sporothrix species and C. albicans, two well-recognized human pathogens. Covered issues include a brief account of Sporothrix, sporotrichosis, the different types of glycosidases, their substrates, and mechanism of action, recent advances in their identification and characterization, their potential biotechnological applications, and the limitations and challenges of their study given the rather poor available information.

3.
Med Mycol ; 61(7)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37410609

RESUMO

The species of the Candida genus are opportunistic pathogenic fungi found in humans and are responsible for ∼80% of worldwide fungal infections. Aimed at diminishing and preventing Candida adhesion to cells or implanted devices in the human host, a large diversity of materials has been developed and functionalized that have attracted much interest. Furthermore, these materials have been focused almost exclusively on Candida albicans, followed by C. glabrata, C. parapsilosis, and C. tropicalis. Although an important diversity of materials has been synthesized to prevent adherence and formation of biofilms by Candida species, it is however important to evaluate the capacity of each material in terms of its property to diminish the adherence of Candida. These materials are discussed in this review.


Assuntos
Candida albicans , Candida , Animais , Humanos , Biofilmes , Candida glabrata , Antifúngicos
4.
Front Cell Infect Microbiol ; 12: 976924, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211971

RESUMO

The cell wall (CW) of fungi exhibits a complex structure and a characteristic chemical composition consisting almost entirely of interacting crystalline and amorphous polysaccharides. These are synthesized by a number of sugar polymerases and depolymerases encoded by a high proportion of the fungal genome (for instance, 20% in Saccharomyces cerevisiae). These enzymes act in an exquisitely coordinated process to assemble the tridimensional and the functional structure of the wall. Apart from playing a critical role in morphogenesis, cell protection, viability and pathogenesis, the CW represents a potential target for antifungals as most of its constituents do not exist in humans. Chitin, ß-glucans and cellulose are the most frequent crystalline polymers found in the fungal CW. The hexosamine biosynthesis pathway (HBP) is critical for CW elaboration. Also known as the Leloir pathway, this pathway ends with the formation of UDP-N-GlcNAc after four enzymatic steps that start with fructose-6-phosphate and L-glutamine in a short deviation of glycolysis. This activated aminosugar is used for the synthesis of a large variety of biomacromolecules in a vast number of organisms including bacteria, fungi, insects, crustaceans and mammalian cells. The first reaction of the HBP is catalyzed by GlcN-6-P synthase (L-glutamine:D-fructose-6-phosphate amidotransferase; EC 2.6.1.16), a critical enzyme that has been considered as a potential target for antifungals. The enzyme regulates the amount of cell UDP-N-GlcNAc and in eukaryotes is feedback inhibited by the activated aminosugar and other factors. The native and recombinant forms of GlcN-6-P synthase has been purified and characterized from both prokaryotic and eukaryotic organisms and demonstrated its critical role in CW remodeling and morphogenesis after exposure of some fungi to agents that stress the cell surface by interacting with wall polymers. This review deals with some of the cell compensatory responses of fungi to wall damage induced by Congo Red and Calcofluor White.


Assuntos
Sporothrix , beta-Glucanas , Animais , Antifúngicos , Benzenossulfonatos , Parede Celular/metabolismo , Celulose , Quitina , Vermelho Congo , Glutamina , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/genética , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Hexosaminas/análise , Hexosaminas/metabolismo , Humanos , Mamíferos/metabolismo , Polímeros/análise , Sporothrix/metabolismo , Açúcares , Difosfato de Uridina , beta-Glucanas/análise
5.
Pediatr Nephrol ; 37(11): 2547-2557, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35237863

RESUMO

Pediatric chronic kidney disease (CKD) is characterized by many co-morbidities, including impaired growth and development, CKD-mineral and bone disorder, anemia, dysregulated iron metabolism, and cardiovascular disease. In pediatric CKD cohorts, higher circulating concentrations of fibroblast growth factor 23 (FGF23) are associated with some of these adverse clinical outcomes, including CKD progression and left ventricular hypertrophy. It is hypothesized that lowering FGF23 levels will reduce the risk of these events and improve clinical outcomes. Reducing FGF23 levels in CKD may be accomplished by targeting two key stimuli of FGF23 production-dietary phosphate absorption and iron deficiency. Ferric citrate is approved for use as an enteral phosphate binder and iron replacement product in adults with CKD. Clinical trials in adult CKD cohorts have also demonstrated that ferric citrate decreases circulating FGF23 concentrations. This review outlines the possible deleterious effects of excess FGF23 in CKD, summarizes data from the adult CKD clinical trials of ferric citrate, and presents the Ferric Citrate and Chronic Kidney Disease in Children (FIT4KiD) study, a randomized, placebo-controlled trial to evaluate the effects of ferric citrate on FGF23 in pediatric patients with CKD stages 3-4 (ClinicalTrials.gov Identifier NCT04741646).


Assuntos
Insuficiência Renal Crônica , Criança , Compostos Férricos , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Ferro/uso terapêutico , Minerais , Fosfatos , Ensaios Clínicos Controlados Aleatórios como Assunto , Insuficiência Renal Crônica/complicações
6.
Antonie Van Leeuwenhoek ; 115(4): 505-519, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35175437

RESUMO

The most frequently isolated human fungal pathogen is Candida albicans which is responsible for about 50% of all Candida infections. In healthy individuals, this organism resides as a part of the normal microbiota in equilibrium with the host. However, under certain conditions, particularly in immunocompromised patients, this opportunistic pathogen adheres to host cells causing serious systemic infections. Thus, much effort has been dedicated to the study of its physiology with emphasis on factors associated to pathogenicity. A representative analysis deals with the mechanisms of glycoprotein assembly as many cell surface antigens and other macromolecules that modulate the immune system fall within this chemical category. In this regard, studies of the terminal protein glycosylation stage which occurs in Golgi vesicles has led to the identification of nucleotidases that convert glycosyltransferase-generated dinucleotides into the corresponding mononucleotides, thus playing a double function: their activity prevent inhibition of further glycosyl transfer by the accumulation of dinucleotides and the resulting mononucleotides are exchanged by specific membrane transporters for equimolecular amounts of sugar donors from the cytosol. Here, using a simple protocol for protein separation we isolated a bifunctional nucleotidase from C. albicans active on GDP and UDP that was characterized in terms of its molecular mass, response to bivalent ions and other factors, substrate specificity and affinity. Results are discussed in terms of the similarities and differences of this nucleotidase with similar counterparts from other organisms thus contributing to the knowledge of a bifunctional diphosphatase not described before in C. albicans.


Assuntos
Candida albicans , Candidíase , Humanos , Pirofosfatases/metabolismo
7.
Antonie Van Leeuwenhoek ; 114(5): 609-624, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33660079

RESUMO

It is well documented that disturbance of cell surface by some agents triggers compensatory responses aimed to maintain the cell wall integrity in fungi and other organisms. Here, the thermodimorphic fungus Sporothrix globosa, a member of the pathogenic clade of the Sporothrix complex, was propagated in yeast-peptone-dextrose medium under conditions to obtain the mycelium (pH 4.5, 27-28 °C) or the yeast (pH 7.8, 32-34 °C) morphotypes in the absence and presence of the wall-interacting dyes Congo Red (CR) and Calcofluor White (CFW) either alone or in combination. After different periods of time, growth, cell morphology and activity of glucosamine-6-phosphate synthase (GlcN-6-P synthase), an ubiquitous enzyme that plays a crucial role in cell wall biogenesis, were determined. CR and to a lower extent CFW affected growth and morphology of both fungal morphotypes and significantly increased enzyme activity. Notoriously, CR or CR in combination with CFW induced the transient conversion of yeasts into conidia-forming filamentous cells even under culture conditions adjusted for yeast development, most likely as a strategy to evade the noxious effect of the dye. After sometime, hypha returned to yeast cells. An hypothetical model to explain the effect of CR on morphology and enzyme activity based on the possible role of membrane-spanning proteins known as mechanosensors is proposed. Results are discussed in terms of the fungal responses to cell wall damage.


Assuntos
Sporothrix , Benzenossulfonatos , Parede Celular , Vermelho Congo
8.
Rev. colomb. anestesiol ; 48(2): 78-84, Jan.-June 2020. tab, graf
Artigo em Inglês | LILACS, COLNAL | ID: biblio-1115560

RESUMO

Abstract Introduction: Pain control in total knee arthroplasty (TKA) is a determining factor in the patient's rehabilitation process. With conventional peripheral blocking techniques for the posterior compartment, foot drop, and distal motor deficit have been reported. The infiltration between popliteal artery and capsule of the knee (IPACK) block is a promising emerging analgesic technique. Objective: To describe analgesic control, opioid consumption, and mobility of patients scheduled for TKA using IPACK block as adjunct analgesic to the femoral block. Methods: We conducted a prospective observational cohort study over a 6-month period in adults taken to TKA. Sociodemographic and anthropometric characteristics, laterality, postoperative pain, and opioid consumption, patient and surgeon satisfaction (Likert), postoperative nausea and vomiting, and walk in the first 24hours, were evaluated and reported with a descriptive analysis. Results: Twenty-seven patients taken to TKA received an IPACK block. The pain score remained in a mild level during the 48 hours of evaluation. In 73% of the cases, an opioid rescue dose was not required; 81% of the patients managed to walk in the first 24 hours. Conclusion: The IPACK block, combined with femoral block and neuraxial anesthesia, turn out to be an excellent analgesic strategy for TKA, achieving adequate pain management, prompt rehabilitation, and early ambulation of the patient.


Resumen Introducción: El control del dolor en artroplastia total de rodilla (ATR) es determinante en el proceso de rehabilitación del paciente. Con las técnicas convencionales de bloqueo periférico para el compartimiento posterior se ha reportado pie caído y déficit motor distal. Por lo anterior, se decidió evaluar en una cohorte las cualidades analgésicas del bloqueo IPACK como una técnica emergente prometedora. Objetivo: Describir el control analgésico, consumo de opioides y movilidad de pacientes programados para ATR usando bloqueo IPACK como adyuvante analgésico al bloqueo femoral. Métodos: Se realizó un estudio de cohorte prospectivo, en adultos llevados a ATR, durante 6 meses. Se evaluaron las características sociodemográficas, antropométricas, lateralidad, dolor postopera torio y consumo de opioides, satisfacción del paciente y del cirujano, náuseas y vómito postoperatorio, caminata en las primeras 48 h. Se informar los resultados de forma descriptiva. Resultados: En total, 27 pacientes a quienes se les realizó ATR obtuvieron bloqueo IPACK. La puntuación del dolor se mantuvo en una escala leve en un rango de 1-3 durante las 48 horas de seguimiento. En el 73% de los casos no se requirió una dosis de opioide de rescate. El 81% de los pacientes logró caminar en las primeras 24 horas. Conclusión: El IPACK, combinado con el bloqueo femoral y la anestesia neuroaxial, resultan ser una excelente estrategia analgésica para logar un adecuado control del dolor en ATR, pronta rehabilitación y deambulación temprana del paciente.


Assuntos
Humanos , Feminino , Idoso , Artéria Femoral , Joelho , Bloqueio Nervoso , Artroplastia , Procedimentos Ortopédicos/reabilitação , Analgesia
9.
Front Plant Sci ; 10: 1100, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31620144

RESUMO

Urban trees are subjected to numerous biotic and mechanical damages, which can affect their growth rates and health. However, for most species, a systematic analysis of tree above- and below-ground growth reactions to a variety of damages is still lacking. Under a fully factorial experimental setup, using two common urban trees (Celtis occidentalis, Fraxinus pennsylvanica), we tested the effects of various degrees of frequently occurring damage as defoliation, root reduction, and stem injuries for a total of 18 treatments. We hypothesized that (i) an increasing amount of damage would proportionally negatively affect both root and stem growth; (ii) there would be a lag or lasting effect on growth; and (iii) both species would react similarly to the treatments. Contrary to our expectation, increasing levels of single or combined damage did not have an incremental effect on either stem or root growth. Although Celtis was significantly less vigorous than Fraxinus, it did not react strongly to damage treatments compared to the control. Interestingly, Celtis that experienced stem damage alone or in combination with other damages showed higher growth rates than the control. For Celtis, root injury was the treatment having the most impact, decreasing both root and stem growth consistently throughout the 5 years following treatments, whereas defoliation decreased growth only in the first 2 years. All damage treatments negatively affected stem and root growth of Fraxinus trees. Stem growth was affected the most by defoliation in the first year following the treatment, while root injury became the driving factor in subsequent years. For both species, stem injury showed the least influence on growth rates. The control and low-level damage treatments often affected growth rates in a similar way, suggesting that low-intensity stress triggers compensatory reactions stimulating photosynthetic rates and nutrient utilization. The slower-growing tree species, Celtis, showed a less negative reaction to all damage treatments compared to Fraxinus. This study illustrates that various types of above- and below-ground injuries do not have a simple additive effect on tree growth and that trees are capable of compensating for the loss of foliage, roots, or phloem to meet their metabolic demand.

10.
Sci Total Environ ; 639: 195-207, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29787903

RESUMO

Flood risks are dynamically changing over time. Over decades and centuries, the main drivers for flood risk change are influenced either by perturbations or slow alterations in the natural environment or, more importantly, by socio-economic development and human interventions. However, changes in the natural and human environment are intertwined. Thus, the analysis of the main drivers for flood risk changes requires a disentangling of the individual risk components. Here, we present a method for isolating the individual effects of selected drivers of change and selected flood risk management options based on a model experiment. In contrast to purely synthetic model experiments, we built our analyses upon a retro-model consisting of several spatio-temporal stages of river morphology and settlement structure. The main advantage of this approach is that the overall long-term dynamics are known and do not have to be assumed. We used this model setup to analyse the temporal evolution of the flood risk, for an ex-post evaluation of the key drivers of change, and for analysing possible alternative pathways for flood risk evolution under different governance settings. We showed that in the study region the construction of lateral levees and the consecutive river incision are the main drivers for decreasing flood risks over the last century. A rebound effect in flood risk can be observed following an increase in settlements since the 1960s. This effect is not as relevant as the river engineering measures, but it will become increasingly relevant in the future with continued socio-economic growth. The presented approach could provide a methodological framework for studying pathways for future flood risk evolvement and for the formulation of narratives for adapting governmental flood risk strategies to the spatio-temporal dynamics in the built environment.

11.
Forensic Sci Int ; 262: 173-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27022860

RESUMO

Fungi colonizing cadavers are capable of drug metabolism and may thus change the metabolite pattern or concentration of drugs in forensic postmortem samples. The purpose of this study was to check for the presence of such changes by searching fungi-specific metabolites of four model drugs (amitriptyline, metoprolol, mirtazapine, and zolpidem) in decomposed postmortem blood samples from 33 cases involving these drugs. After isolation and identification of fungal strains present in the samples, each isolate was incubated in Sabouraud medium at 25°C for up to 120h with each model drug. One part of the supernatants was directly analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), another after liquid-liquid extraction with chlorobutane and concentration. From 21 out of 33 decomposed postmortem blood samples (64%) a total of 30 different strains could be isolated, one from the class of Ascomycete and the rest belonging to 15 species from 8 different genera (number of species): Aspergillus (2), Botrytis (1), Candida (8), Fusarium (1), Mucor (1), Penicillium (1), and Rodothorula (1). In the in vitro studies, these microorganisms were found capable of N-demethylation and N-oxidation of amitriptyline and mirtazapine, O-demethylation followed by side chain oxidation of metoprolol as well as hydroxylation of all four-model drugs. In two of the postmortem blood samples, from which the fungi Aspergillus jensenii, Candida parapsilosis. and Mucor circinelloides had been isolated, a fungi-specific hydroxy zolpidem metabolite was detected. The presence of this metabolite in postmortem samples likely indicates postmortem fungal biodegradation.


Assuntos
Amitriptilina/sangue , Fungos/isolamento & purificação , Metoprolol/sangue , Mianserina/análogos & derivados , Mudanças Depois da Morte , Piridinas/sangue , Idoso , Biotransformação , Fármacos Cardiovasculares/sangue , Fármacos do Sistema Nervoso Central/sangue , Cromatografia Líquida , Feminino , Humanos , Masculino , Mianserina/sangue , Pessoa de Meia-Idade , Mirtazapina , Espectrometria de Massas em Tandem , Zolpidem
12.
World J Pediatr Congenit Heart Surg ; 6(3): 401-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26180155

RESUMO

BACKGROUND: Acute kidney injury (AKI) and fluid overload have been shown to increase morbidity and mortality. The reported incidence of AKI in pediatric patients following surgery for congenital heart disease is between 15% and 59%. Limited data exist looking at risk factors and outcomes of AKI or fluid overload in neonates undergoing surgery for congenital heart disease. METHODS: Neonates aged 6 to 29 days who underwent surgery for congenital heart disease and who were without preoperative kidney disease were included in the study. The AKI was determined utilizing the Acute Kidney Injury Network criteria. RESULTS: Ninety-five neonates were included in the study. The incidence of neonatal AKI was 45% (n = 43), of which 86% had stage 1 AKI. Risk factors for AKI included cardiopulmonary bypass time, selective cerebral perfusion, preoperative aminoglycoside use, small kidneys by renal ultrasound, and risk adjustment for congenital heart surgery category. There were eight mortalities (five from stage 1 AKI group, three from stage 2, and zero from stage 3). Fluid overload and AKI both increased hospital length of stay and postoperative ventilator days. CONCLUSION: To avoid increased risk of morbidity and possibly mortality, every attempt should be made to identify and intervene on those risk factors, which may be modifiable or identifiable preoperatively, such as small kidneys by renal ultrasound.


Assuntos
Injúria Renal Aguda/etiologia , Cardiopatias Congênitas/cirurgia , Complicações Pós-Operatórias/etiologia , Desequilíbrio Hidroeletrolítico/etiologia , Injúria Renal Aguda/diagnóstico , Diagnóstico Precoce , Métodos Epidemiológicos , Feminino , Humanos , Lactente , Recém-Nascido , Terapia Intensiva Neonatal , Masculino , Complicações Pós-Operatórias/diagnóstico , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Desequilíbrio Hidroeletrolítico/diagnóstico
13.
Drug Test Anal ; 7(4): 265-79, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24898183

RESUMO

The present study investigated the in vitro metabolic capacity of 28 fungal strains isolated from post-mortem material towards five model drugs: amitriptyline, metoprolol, mirtazapine, promethazine, and zolpidem. Each fungal strain was incubated at 25 °C for up to 120 h with each of the five models drugs. Cunninghamella elegans was used as positive control. Aliquots of the incubation mixture were centrifuged and 50 µL of the supernatants were diluted and directly analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) with product ion scanning. The remaining mixture was analyzed by full scan gas chromatography-mass spectrometry (GC-MS) after liquid-liquid extraction and acetylation. The metabolic activity was evaluated through the total number of detected metabolites (NDM) produced in each model and fungal strains and the percentage of parent drug remaining (%RPD) after up to five days of incubation. All the tested fungal strains were capable of forming mammalian phase I metabolites. Fungi from the normal fungal flora of the human body such as Candida sp., Geotrichum candidum, and Trichosporon asahii) formed up to seven metabolites at %RPD values greater than 52% but no new fungal metabolites (NFM). In contrast, some airborne fungal strains like Bjerkandera adusta, Chaetomium sp, Coriolopsis sp., Fusarium solani and Mucor plumbeus showed NDM values exceeding those of the positive control, complete metabolism of the parent drug in some models and formation of NFM. NFM (numbers in brackets) were detected in four of the five model drugs: amitriptyline (18), metoprolol (4), mirtazapine (8), and zolpidem (2). The latter NFM are potential candidates for marker substances indicating post-mortem fungal metabolism.


Assuntos
Amitriptilina/metabolismo , Cadáver , Fungos/metabolismo , Metoprolol/metabolismo , Mianserina/análogos & derivados , Prometazina/metabolismo , Piridinas/metabolismo , Biotransformação , Fungos/isolamento & purificação , Humanos , Mianserina/metabolismo , Mirtazapina , Zolpidem
14.
PLoS One ; 8(10): e76308, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24155899

RESUMO

Insect pollination benefits over three quarters of the world's major crops. There is growing concern that observed declines in pollinators may impact on production and revenues from animal pollinated crops. Knowing the distribution of pollinators is therefore crucial for estimating their availability to pollinate crops; however, in general, we have an incomplete knowledge of where these pollinators occur. We propose a method to predict geographical patterns of pollination service to crops, novel in two elements: the use of pollinator records rather than expert knowledge to predict pollinator occurrence, and the inclusion of the managed pollinator supply. We integrated a maximum entropy species distribution model (SDM) with an existing pollination service model (PSM) to derive the availability of pollinators for crop pollination. We used nation-wide records of wild and managed pollinators (honey bees) as well as agricultural data from Great Britain. We first calibrated the SDM on a representative sample of bee and hoverfly crop pollinator species, evaluating the effects of different settings on model performance and on its capacity to identify the most important predictors. The importance of the different predictors was better resolved by SDM derived from simpler functions, with consistent results for bees and hoverflies. We then used the species distributions from the calibrated model to predict pollination service of wild and managed pollinators, using field beans as a test case. The PSM allowed us to spatially characterize the contribution of wild and managed pollinators and also identify areas potentially vulnerable to low pollination service provision, which can help direct local scale interventions. This approach can be extended to investigate geographical mismatches between crop pollination demand and the availability of pollinators, resulting from environmental change or policy scenarios.


Assuntos
Abelhas/fisiologia , Produtos Agrícolas/fisiologia , Modelos Teóricos , Polinização/fisiologia , Animais , Calibragem , Fabaceae/fisiologia , Especificidade da Espécie , Reino Unido
15.
PLoS One ; 8(9): e74834, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24040347

RESUMO

Human migration north through Africa is contentious. This paper uses a novel palaeohydrological and hydraulic modelling approach to test the hypothesis that under wetter climates c.100,000 years ago major river systems ran north across the Sahara to the Mediterranean, creating viable migration routes. We confirm that three of these now buried palaeo river systems could have been active at the key time of human migration across the Sahara. Unexpectedly, it is the most western of these three rivers, the Irharhar river, that represents the most likely route for human migration. The Irharhar river flows directly south to north, uniquely linking the mountain areas experiencing monsoon climates at these times to temperate Mediterranean environments where food and resources would have been abundant. The findings have major implications for our understanding of how humans migrated north through Africa, for the first time providing a quantitative perspective on the probabilities that these routes were viable for human habitation at these times.


Assuntos
Clima , Migração Humana , Rios , África , África do Norte , Simulação por Computador , Clima Desértico , Geografia , Humanos , Região do Mediterrâneo , Modelos Teóricos , Dinâmica Populacional , Chuva , Reprodutibilidade dos Testes
16.
Rev. salud pública ; 15(5): 729-742, set.-oct. 2013. tab
Artigo em Espanhol | LILACS | ID: lil-709099

RESUMO

RESUMEN El objetivo del presente trabajo fue identificar las políticas públicas que se han desarrollado en los países latinoamericanos frente a la intervención de los Determinantes Sociales de la Salud. Para esto se realizó una revisión temática de artículos científicos a partir de bases de datos y de documentos oficiales de organismos multilaterales y de los Ministerios de Salud de los 22 países latinoamericanos. Se hace un recuento del concepto e historia de los determinantes sociales de la salud de la Organización Mundial de la Salud y del trabajo desarrollado en el ámbito mundial en regiones como Europa, así como en Latinoamérica. Posteriormente se describen como ejemplos los casos de ocho países (Argentina, Brasil, Bolivia, Chile, Colombia, Costa Rica, México y Venezuela) y las políticas públicas desarrolladas en el área de estudio. Se concluye que en Latinoamérica hay un panorama desigual de aplicación de políticas de abordaje hacia los determinantes sociales de la salud así como una intervención segmentada principalmente hacia los determinantes intermedios de la salud, sin tener en cuenta la intervención integral desde diferentes puntos de entrada, según el marco conceptual.


ABSTRACT The study was aimed at identifying Latin-American countries’ public policy which has been related to the social determinants of health. A topic review was thus made of papers kept in the 22 Latin-American countries’ databases and official documents issued by their multilateral organisations and ministries of health. The World Health Organization’s concept of the social determinants of health has been summarised and a history given of the pertinent work developed worldwide in regions such as Europe and Latin-America. Public policy regarding the field of study in Argentina, Brazil, Bolivia, Chile, Colombia, Costa Rica, México and Venezuela has been described. It was concluded that Latin-America provides a panorama of inequality regarding the application of policy concerning the social determinants of health and that there was segmented intervention, mainly regarding intermediate determinants of health, without taking an integrated approach from different entrance points into account, according to the stated conceptual framework.


Assuntos
Humanos , Política Pública , Determinantes Sociais da Saúde , América Latina , Estados Unidos
17.
Anal Bioanal Chem ; 405(26): 8443-50, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23954943

RESUMO

Cadavers can be colonized by a wide variety of bacteria and fungi. Some of these microbes could change the concentration or the metabolic pattern of drugs present in postmortem samples. The purpose of this study was to identify fungi from human postmortem material and to further assess their potential role in the metabolism of drugs. Aliquots of 252 postmortem samples (heart blood, liver, kidney, and lung) taken from 105 moderately to severely decomposed bodies were streaked on Sabouraud agar for isolation of fungal species. One part of the samples was worked up immediately after autopsy (group I). The second part had previously been stored at -20 °C for at least 1 year (group II). Identification of the isolates was achieved morphologically by microscopy and molecularly by polymerase chain reaction amplification and sequencing of markers allowing species identification of the respective genera. Depending on the genus, different gene fragments were used: calmodulin for Aspergillus, ß-tubulin for Penicillium, translation elongation factor 1α for Fusarium, and the internal transcribed spacer region of the ribosomal DNA for all remaining genera. A total of 156 fungal strains were isolated from 62% of the postmortem materials. By using these primers, 98% of the isolates could be identified to the species level. The most common genera were Candida (60.0%-six species), Penicillium (10.3%-two species), Rhodotorula (7.1%-one species), Mucor (6.4%-four species), Aspergillus (3.2%-four species), Trichosporon (3.2%-one species), and Geotrichum (3.2%-one species). Group I samples contained 53% more fungal species than stored samples suggesting some fungi did not survive the freezing process. The isolated fungi might be characteristic for decomposed bodies. The proposed methodology proved to be appropriate for the identification of fungi in this type of material.


Assuntos
DNA Fúngico/isolamento & purificação , Fungos/isolamento & purificação , Preparações Farmacêuticas/metabolismo , Adulto , Idoso , Autopsia , Sequência de Bases , Cadáver , DNA Fúngico/genética , Feminino , Fungos/genética , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA
18.
Dis Markers ; 34(3): 163-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23334650

RESUMO

MicroRNAs (miRNAs) are a class of small, non-coding RNA molecules that can regulate gene expression, thereby affecting crucial processes in cancer development. miRNAs offer great potential as biomarkers for cancer detection because of their remarkable stability in blood and their characteristic expression in different diseases. We investigated whether quantitative RT-PCR miRNA profiling on serum could discriminate between breast cancer patients and healthy controls. We performed miRNA profiling on serum from breast cancer patients, followed by construction of ROC (Receiver Operating Characteristic) curves to determine the sensitivity and specificity of the assay. We found that seven miRNAs (miR-10b, miR-21, miR-125b, miR-145, miR-155 miR-191 and miR-382) had different expression patterns in serum of breast cancer patients compared to healthy controls. ROC curve analyses revealed that three serum miRNAs could be valuable biomarkers for distinguishing BC from normal controls. Additionally, a combination of ROC curve analyses of miR-145, miR-155 and miR-382 showed better sensitivity and specificity of our assay. miRNA profiling in serum has potential as a novel method for breast cancer detection in the Mexican population.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/diagnóstico , Perfilação da Expressão Gênica , MicroRNAs/sangue , RNA Mensageiro/genética , Adulto , Idoso , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Curva ROC , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade
19.
Eur Urol ; 64(4): 588-97, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23245816

RESUMO

CONTEXT: Postoperative paralytic ileus (POI) has profound clinical consequences because it represents a substantial burden on both patients and health care resources. OBJECTIVE: To determine the knowledge base regarding POI in the radical cystectomy (RC) population with an emphasis on preventive measures and risk factors. EVIDENCE ACQUISITION: A systematic literature search of Medline (1966 to February 2011) and a study review were conducted. Eligible studies explicitly reported the incidence of POI and/or at least two quantitative measures of gastrointestinal recovery. EVIDENCE SYNTHESIS: The search identified 727 relevant articles; 77 met eligibility criteria, comprising 13 793 patients. Of these, 21 used explicit definitions of POI, and they varied widely. Across studies, the incidence of POI ranged from 1.58% to 23.5%. Possible risk factors for POI included increasing age and body mass index. Seventeen studies reported effects of an intervention on POI: 3 randomized controlled studies, 11 observational cohort studies with concurrent comparison, and 3 observational cohort studies with nonconcurrent comparison. Gum chewing was associated with shortened times to flatus (2.4 vs 2.9 d; p<0.0001) and bowel movement (BM) (3.2 vs 3.9 d; p<0.001) in one observational cohort study (n=102); omission of a postoperative nasogastric tube (NGT) was associated with shorter time to flatus (4.21 vs 5.33 d; p=0.0001) and shorter length of stay (14.4 vs 19.1 d; p=0.001) in one observational cohort study (n=430); and the routine use of bowel preparation was associated with an increased incidence of POI (5% vs 19%) in another series (n=86). Additionally, readaptation of the dorsolateral peritoneal layer was shown to shorten times to flatus (p=0.016) and times to BM (p=0.011) in one randomized controlled study (n=200). CONCLUSIONS: The incidence/definition of POI after RC is highly variable. An improved reporting strategy is needed to identify true incidence and risk factors, and to guide future research for both potential preventive and therapeutic interventions.


Assuntos
Cistectomia/efeitos adversos , Pseudo-Obstrução Intestinal/epidemiologia , Pseudo-Obstrução Intestinal/prevenção & controle , Fatores Etários , Índice de Massa Corporal , Humanos , Incidência , Pseudo-Obstrução Intestinal/classificação , Pseudo-Obstrução Intestinal/diagnóstico , Pseudo-Obstrução Intestinal/fisiopatologia , Recuperação de Função Fisiológica , Fatores de Risco , Terminologia como Assunto , Fatores de Tempo , Resultado do Tratamento
20.
Rev Salud Publica (Bogota) ; 15(5): 731-42, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-25124248

RESUMO

The study was aimed at identifying Latin-American countries' public policy which has been related to the social determinants of health. A topic review was thus made of papers kept in the 22 Latin-American countries' databases and official documents issued by their multilateral organisations and ministries of health. The World Health Organization's concept of the social determinants of health has been summarised and a history given of the pertinent work developed worldwide in regions such as Europe and Latin-America. Public policy regarding the field of study in Argentina, Brazil, Bolivia, Chile, Colombia, Costa Rica, México and Venezuela has been described. It was concluded that Latin-America provides a panorama of inequality regarding the application of policy concerning the social determinants of health and that there was segmented intervention, mainly regarding intermediate determinants of health, without taking an integrated approach from different entrance points into account, according to the stated conceptual framework.


Assuntos
Política Pública , Determinantes Sociais da Saúde , Humanos , América Latina , Estados Unidos
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