RESUMO
Paper-based analytical devices (PADs) are powerful platforms for point-of-need testing since they are inexpensive devices fabricated in different shapes and miniaturized sizes, ensuring better portability. Additionally, the readout and detection systems can be accomplished with portable devices, allying with the features of both systems. These devices have been introduced as promising analytical platforms to meet critical demands involving rapid, reliable, and simple testing. They have been applied to monitor species related to environmental, health, and food issues. Herein, an outline of chronological events involving PADs is first reported. This work also introduces insights into fundamental parameters to engineer new analytical platforms, including the paper type and device operation. The discussions involve the main analytical techniques used as detection systems, such as colorimetry, fluorescence, and electrochemistry. It also showed recent advances involving PADs, especially combining optical and electrochemical detection into a single device. Dual/combined detection systems can overcome individual barriers of the analytical techniques, making possible simultaneous determinations, or enhancing the devices' sensitivity and/or selectivity. In addition, this review reports on distance-based detection, which is also considered a trend in analytical chemistry. Distance-based detection offers instrument-free analyses and avoids user interpretation errors, which are outstanding features for analyses at the point of need, especially for resource-limited regions. Finally, this review provides a critical overview of the practical specifications of the recent analytical platforms involving PADs, demonstrating their challenges. Therefore, this work can be a highly useful reference for new research and innovation.
RESUMO
Fat burners are a category of nutritional supplements that are claimed to increase the metabolism and promote greater energy expenditure, leading to weight loss. However, little is known about the side effects on gastrointestinal motility. In this study, we evaluated the effect of ingestion with a fat burner named Thermbuterol® (THERM) on the gastric motility and food behavior of mice. THERM compounds were identified using nuclear magnetic resonance (NMR). Mice received variable doses of THERM (10, 50, 100 or 300 âmg/kg, p.o.) or NaCl 0.15 âM (control). Gastric emptying (GE) was assessed using the phenol red technique. Another set of mice was pretreated with intraperitoneal administration of hexamethonium (HEXA, 10 âmg/kg), prazosin (PRAZ, 0.25 âmg/kg), propranolol (PROP, 2 âmg/kg), parachlorophenylalanine (PCPA, 300 âmg/kg) or ondansetron (ONDA, 50 âµg/kg) 30 âmin before THERM treatment for evaluation of GE. We assessed the gastrointestinal responsiveness in vitro as well as THERM's effects on food behavior. Caffeine was the major compound of THERM, identified by NMR. THERM 100 and 300 âmg/kg decreased GE compared to the respective controls. Pretreatment with PRAZ or PROP did not prevent gastric dysmotility induced by THERM 100 âmg/kg. However, the pretreatment with HEXA, ONDA or PCPA prevented GE delay induced by THERM. In vitro, THERM relaxed contractions in strips of longitudinal gastric fundus and duodenum. THERM also increased food intake, which was prevented by PCPA and ONDA treatments. THERM decreased GE of a liquid and increased food intake in mice, a phenomenon mediated by the autonomic nicotinic receptors and serotoninergic receptor.
RESUMO
Around 27% of South Americans live in central and southern Brazil. Of 19,400 human malaria cases in Brazil in 2018, some were from the southern and southeastern states. High abundance of malaria vectors is generally positively associated with malaria incidence. Expanding geographic distributions of Anopheles vector mosquito species (e.g. A. cruzii) in the face of climate change processes would increase risk of such malaria transmission; such risk is of particular concern in regions that hold human population concentrations near present limits of vector species' geographic distributions. We modeled effects of likely climate changes on the distribution of A. cruzii, evaluating two scenarios of future greenhouse gas emissions for 2050, as simulated in 21 general circulation models and two greenhouse gas scenarios (RCP 4.5 and RCP 8.5) for 2050. We tested 1305 candidate models, and chose among them based on statistical significance, predictive performance, and complexity. The models closely approximated the known geographic distribution of the species under current conditions. Under scenarios of future climate change, we noted increases in suitable area for the mosquito vector species in São Paulo and Rio de Janeiro states, including areas close to 30 densely populated cities. Under RCP 8.5, our models anticipate areal increases of >75% for this important malaria vector in the vicinity of 20 large Brazilian cities. We developed models that anticipate increased suitability for the mosquito species; around 50% of Brazilians reside in these areas, and â¼89% of foreign tourists visit coastal areas in this region. Under climate change thereefore, the risk and vulnerability of human populations to malaria transmission appears bound to increase.
Assuntos
Anopheles , Malária , Animais , Brasil/epidemiologia , Mudança Climática , Florestas , Humanos , Malária/epidemiologia , Mosquitos VetoresRESUMO
A survey for species of the genus Trichoderma occurring as endophytes of Coffea, and as mycoparasites of coffee rusts (Hemileia), was undertaken in Africa; concentrating on Cameroon and Ethiopia. Ninety-four isolates of Trichoderma were obtained during this study: 76 as endophytes of healthy leaves, stems and berries and, 18 directly from colonized rust pustules. A phylogenetic analysis of all isolates used a combination of three genes: translation elongation factor-1α (tef1), rpb2 and cal for selected isolates. GCPSR criteria were used for the recognition of species; supported by morphological and cultural characters. The results reveal a previously unrecorded diversity of Trichoderma species endophytic in both wild and cultivated Coffea, and mycoparasitic on Hemileia rusts. Sixteen species were delimited, including four novel taxa which are described herein: T. botryosum, T. caeruloviride, T. lentissimum and T. pseudopyramidale. Two of these new species, T. botryosum and T. pseudopyramidale, constituted over 60% of the total isolations, predominantly from wild C. arabica in Ethiopian cloud forest. In sharp contrast, not a single isolate of Trichoderma was obtained using the same isolation protocol during a survey of coffee in four Brazilian states, suggesting the existence of a 'Trichoderma void' in the endophyte mycobiota of coffee outside of Africa. The potential use of these African Trichoderma isolates in classical biological control, either as endophytic bodyguards-to protect coffee plants from Hemileia vastatrix, the fungus causing coffee leaf rust (CLR)-or to reduce its impact through mycoparasitism, is discussed, with reference to the on-going CLR crisis in Central America.
Assuntos
Coffea/crescimento & desenvolvimento , Coffea/parasitologia , Endófitos/isolamento & purificação , Parasitos/isolamento & purificação , Trichoderma/isolamento & purificação , África , Animais , Teorema de Bayes , Biodiversidade , Endófitos/citologia , Florestas , Parasitos/citologia , Filogenia , Especificidade da Espécie , Inquéritos e Questionários , Trichoderma/citologiaRESUMO
The causes of the gradients in species richness remain contentious because of multiple competing hypotheses, significant knowledge gaps, and regional effects of environmental and historical factors on species pools. Coastal zones are subject to particular sets of environmental constraints, thus identifying the drivers of species richness therein should shed light on the regional gradients of species diversity. Here, we investigate the geographic patterns and drivers of plant diversity across coastal regions while allowing for pervasive sampling deficiencies. Based on 142708 records of flowering plant occurrences, we mapped species richness and estimated the level of knowledge across the coastal zone of Brazil. Based on inventory completeness, we used linear regression models to test the predictive power of environmental variables that represent different environmental hypotheses. Few cells (25%) were well-surveyed, reflecting little knowledge about the distribution and diversity of flowering plants on the highly-populated Brazilian coast. Still, we found support for the habitat heterogeneity hypothesis as the best explanation of the variation in species richness of flowering plants in this region. Soil properties and water constraints are also important factors. Although our work emphasises the paucity of information on plant diversity in tropical and human-dominated areas, we show that knowledge limitations should not curb our capability of addressing hypotheses about species diversity.
Assuntos
Biodiversidade , Magnoliopsida , Brasil , Ecossistema , Humanos , PlantasRESUMO
BACKGROUND: Although produced by several types of tumours, the role of serotonin on cancer biology is yet to be understood. METHODS: The effects of serotonin (5-HT) on human breast cancer cells proliferation, signalling pathways and metabolic profile were evaluated by cytometry, western blotting, qPCR, enzymology and confocal microscopy. RESULTS: Our results revealed that incubation of MCF-7 cells with 10 µM 5-HT increased cell growth rate by 28%, an effect that was prevented by the 5-HTR2A/C antagonist, ketanserin. Conversely, increasing concentrations of 5-HT promoted glucose consumption and lactate production by MCF-7 cells. We also showed that increased glucose metabolism is provoked by the upregulation of pyruvate kinase M2 (PKM2) isoform through 5-HTR2A/C-triggered activation of Jak1/STAT3 and ERK1/2 subcellular pathways. However, we noticed a decrease in the rate of produced lactate per consumed glucose as a function of the hormone concentration, suggesting a disruption of the Warburg effect. The latter effect is due to 5-HTR2A/C-dependent mitochondrial biogenesis and metabolism, which is triggered by adenylyl cyclase/PKA, enhancing the oxidation of lactate within these cells. CONCLUSIONS: We showed that serotonin, through 5-HTR2A/C, interferes with breast cancer cells proliferation and metabolism by triggering two distinct signalling pathways: Jak1/STAT3 that boosts glycolysis through upregulation of PKM2, and adenylyl cyclase/PKA that enhances mitochondrial biogenesis.
Assuntos
Neoplasias da Mama/genética , Proliferação de Células/efeitos dos fármacos , Janus Quinase 1/genética , Fator de Transcrição STAT3/genética , Adenilil Ciclases/genética , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Transporte/genética , Sobrevivência Celular/efeitos dos fármacos , Feminino , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Ketanserina/farmacologia , Sistema de Sinalização das MAP Quinases/genética , Células MCF-7 , Proteínas de Membrana/genética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Serotonina/farmacologia , Hormônios Tireóideos/genética , Proteínas de Ligação a Hormônio da TireoideRESUMO
The study presented here aims at identifying the source of redox mediators (riboflavin), electron carriers nicotinamide adenine dinucleotide (NAD) and carbon to perform decolorization of azo dye under anaerobic conditions after osmotic shock pretreatment of residual yeast from industrial fermentation. Pretreatment conditions were optimized by Doehlert experiment, varying NaCl concentration, temperature, yeast density and time. After the optimization, the riboflavin concentration in the residual yeast lysate (RYL) was 46% higher than the one present in commercial yeast extract. Moreover, similar NAD concentration was observed in both extracts. Subsequently, two decolorization experiments were performed, that is, a batch experiment (48â h) and a kinetic experiment (102â h). The results of the batch experiment showed that the use of the RYL produced by the optimized method increased decolorization rates and led to color removal efficiencies similar to those found when using the commercial extract (â¼80%) and from 23% to 50% higher when compared to the control (without redox mediators). Kinetics analysis showed that methane production was also higher in the presence of yeast extract and RYL, and biogas was mostly generated after stabilization of color removal. In all kinetics experiments the azo dye degradation followed the pseudo-second-order model, which suggested that there was a concomitant adsorption/degradation of the dye on the biomass cell surface. Therefore, results showed the possibility of applying the pretreated residual yeast to improve color removal under anaerobic conditions, which is a sustainable process.
Assuntos
Compostos Azo , Corantes , NAD/química , Riboflavina/química , Saccharomyces cerevisiae/metabolismo , Adsorção , Anaerobiose , Compostos Azo/química , Compostos Azo/metabolismo , Corantes/química , Corantes/metabolismo , Fermentação , Osmose , Oxirredução , Gerenciamento de Resíduos/métodos , ResíduosRESUMO
White-Nose syndrome (WNS) is an emergent infectious disease that has already killed around six million bats in North America and has spread over two thousand kilometers from its epicenter. However, only a few studies on the possible impacts of the fungus on bat hosts were conducted, particularly concerning its implications for bat conservation. We predicted the consequences of WNS spread by generating a map with potential areas for its occurrence based on environmental conditions in sites where the disease already occurs, and overlaid it with the geographic distribution of all hibernating bats in North America. We assumed that all intersection localities would negatively affect local bat populations and reassessed their conservation status based on their potential population decline. Our results suggest that WNS will not spread widely throughout North America, being mostly restricted to the east and southeast regions. In contrast, our most pessimistic scenario of population decline indicated that the disease would threaten 32% of the bat species. Our results could help further conservation plans to preserve bat diversity in North America.
Assuntos
Quirópteros/microbiologia , Nariz/microbiologia , Animais , Meio Ambiente , Fungos , Micoses/microbiologia , América do Norte , SíndromeRESUMO
Acca sellowiana (Myrtaceae), feijoa (in Brazil, goiaba da serra), is a native southern South America tree that produces edible fruits which, although only occasionally cultivated in South America, became a significant fruit crop in New Zealand. Recently, during surveys for fungal pathogens of feijoa in southern Brazil, several plants were found bearing tar-spot symptoms caused by a species of Phyllachora. A literature search enabled us to identify the fungus as Phyllachora feijoae, a little-known species originally described in the 19(th) century by H. Rehm and later transferred to the genus Catacauma. The name Catacauma feijoae, although now regarded as a later synonym of P. feijoae is still mistakenly in use (as, for instance, in the Brazilian list of fungi on plants). The type specimen was most probably deposited in the Botanisches Garten und Museum Berlin-Dahlem (B) and lost or destroyed during World War II, and could not be located. The recent recollection of abundant material of this fungus in the vicinity of Pelotas (Rio Grande do Sul, Brazil) allowed its re-examination and neotypification. Phyllachora feijoae is also illustrated here for the first time.
RESUMO
This paper demonstrates parallel imaging acceleration of spiral Fourier velocity encoded MRI using the iterative self-consistent parallel imaging reconstruction (SPIRiT) technique. Magnitude images and time-velocity distributions obtained with image domain SPIRiT and sum-of-squares reconstruction are compared, for 2-fold and 4-fold undersampling. We show that SPIRiT is able to reduce spatial aliasing from undersampled time-velocity distributions, with good results for 2-fold undersampling, and moderately good results for 4-fold undersampling.
Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/estatística & dados numéricos , Algoritmos , Velocidade do Fluxo Sanguíneo , Artérias Carótidas/fisiologia , Análise de Fourier , Humanos , Veias Jugulares/fisiologia , Pescoço/irrigação sanguínea , Artéria Vertebral/fisiologiaRESUMO
PURPOSE: Ifosfamide (IFS) is often involved in the occurrence of hemorrhagic cystitis due to direct contact of its metabolite acrolein with uroepithelium. It has been shown that COX-2 is involved in this pathogenesis. Thus, we aimed to study the functional changes on the urinary bladder in the putative modifications induced by IFS, as well as the COX-2 role in this process. MATERIALS AND METHODS: IFS-treated rats were evaluated by cystometrography in absence or presence of COX inhibitors indomethacin or etoricoxib or in the presence of mesna. Experiments with isolated strips of urinary bladder obtained from animals with IFS-induced cystitis, either treated or not treated with COX inhibitors or mesna, were performed. Histological analyses, immunohistochemistry for COX-2, and measurement of plasma PGE(2) were also performed. RESULTS: IFS treatment caused severe inflammation of the bladder tissue. Cystometrography recordings of IFS-treated rats revealed bladder with increased micturition frequency and enhanced filling intravesical pressure. Contractility of the isolated smooth muscle from the rat's bladder with IFS-induced cystitis showed decreased force development in response to KCl and CCh. Almost all effects induced by IFS were ameliorated by the use of COX inhibitors or mesna. Enzyme expression in the urinary bladder tissue was positive, and plasma concentration of PGE(2) was increased in IFS-treated animals and decreased significantly in etoricoxib-treated animals. CONCLUSIONS: IFS causes important changes in the micturition physiology in rats, and the inhibition of the isoenzyme COX-2 could be an important event that could prevent the detrimental effects elicited by IFS-induced hemorrhagic cystitis.
Assuntos
Antineoplásicos Alquilantes/toxicidade , Ciclo-Oxigenase 2/efeitos dos fármacos , Cistite/induzido quimicamente , Hemorragia/induzido quimicamente , Ifosfamida/toxicidade , Animais , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Cistite/fisiopatologia , Dinoprostona/sangue , Modelos Animais de Doenças , Hemorragia/fisiopatologia , Inflamação/induzido quimicamente , Masculino , Mesna/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Ratos , Ratos Wistar , Índice de Gravidade de Doença , Micção/efeitos dos fármacosRESUMO
To determine whether endogenous opiates play a role in the pathogenesis of perinatal asphyxia, a blinded clinical trial of naloxone, a competitive opiate receptor blocker, was undertaken in infants with low 1-minute Apgar scores. Of 85 infants with 1-minute Apgar score 0 to 3, 44 received an injection of naloxone (approximately 0.4 mg/kg) and 41 received saline solution. In 108 infants with 1-minute Apgar score 4 to 6, 54 received naloxone and 54 saline solution. In neither group was there a significant effect of naloxone on respiratory frequency or heart rate up to 30 minutes after injection, nor at 24 hours of age. In both groups active muscle tone of upper and lower limbs was increased by naloxone, a response that may not be beneficial in the face of inadequate oxygen delivery to vital organs. We conclude that naloxone at this dose had no readily apparent benefit in the resuscitation of the asphyxiated newborn infant.
Assuntos
Asfixia Neonatal/tratamento farmacológico , Naloxona/uso terapêutico , Adulto , Índice de Apgar , Asfixia Neonatal/etnologia , Ensaios Clínicos como Assunto , Parto Obstétrico , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Recém-Nascido , Injeções Intramusculares , Trabalho de Parto , Masculino , Idade Materna , Gravidez , Respiração/efeitos dos fármacos , RessuscitaçãoRESUMO
Ten preterm infants (birth weight 0.970 to 2.495 kg) with apnea due to periodic breathing (apneic interval = 5 to 10 seconds) or with "serious apnea" (greater than or equal to 20 seconds) were studied before and after the administration of theophylline. We determined the incidence of apnea, respiratory minute volume, alveolar gases, arterial gases and pH, "specific" compliance, functional residual capacity, and work of breathing. Theophylline decreased the incidence of apnea (P less than .05), increased respiratory minute volume (P less than 0.001), decreased (PACO2 (and PaCO2 P less than 0.001), increased the slope of the CO2 response curve (P less than 0.02) with a significant shift to the left (P less than 0.02). These findings suggest that the decreased incidence of apnea after theophylline is associated with an increase in alveolar ventilation and increased sensitivity to CO2 with a pronounced shift of the CO2 response curve to the left. These data are consistent with the idea that apnea is a reflection of a depressed respiratory system.