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BACKGROUND: Tongue cancer is associated with debilitating diseases and poor prognostic outcomes. The use of imaging techniques like ultrasonography to assist in the clinical management of affected patients is desirable, but its reliability remains debatable. Therefore, the aim of this study is to investigate the importance of ultrasound use for the clinicopathological management of tongue cancer. METHODS: A scoping review was carried out using specific search strategies in the following electronic databases: PubMed/MEDLINE, Scopus, Web of Science, and Google Scholar. Collected data included bibliographical information, study design, ultrasound equipment, the aim of the ultrasonography use, the timing of ultrasound use during oncological treatment (pre-, trans-, and/or post-operatively), and the advantages and disadvantages of the use of the ultrasound. RESULTS: A total of 47 studies were included in this review after following the selection process. The majority of the studies investigated the use of ultrasound pre-operatively for the investigation of lymph node metastases or to determine the tumor thickness and depth of invasion. The sensitivity, specificity, and accuracy of ultrasound to determine clinical lymph node metastases ranged from 47% to 87.2%, from 84.3% to 95.8%, and from 70% to 86.2%, respectively. The sensitivity and specificity to determine the microscopic depth of invasion were 92.3% and from 70.6% to 82.1%, respectively. CONCLUSION: Ultrasonography seems to be a reliable imaging technique for the investigation of important prognostic parameters for tongue cancer, including depth of invasion and lymph node metastases.
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Neoplasias da Língua , Humanos , Neoplasias da Língua/diagnóstico por imagem , Neoplasias da Língua/terapia , Neoplasias da Língua/patologia , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Reprodutibilidade dos Testes , Ultrassonografia , Prognóstico , Estadiamento de Neoplasias , Linfonodos/patologiaRESUMO
A reversible optoelectronic nose is presented consisting of ten acid-base indicators incorporated into a starch-based film, covering a wide pH range. The starch substrate is odorless, biocompatible, flexible, and exhibits high tensile resistance. This optical artificial olfaction system was used to detect the early stages of food decomposition by exposing it to the volatile compounds produced during the spoialge process of three food products (beef, chicken, and pork). A smartphone was used to capture the color changes caused by intermolecular interactions between each dye and the emitted volatiles over time. Digital images were processed to generate a differential color map, which uses the observed color shifts to create a unique signature for each food product. To effectively discriminate among different samples and exposure times, we employed chemometric tools, including hierarchical cluster analysis (HCA) and principal component analysis (PCA). This approach detects food deterioration in a practical, cost-effective, and user-friendly manner, making it suitable for smart packaging. Additionally, the use of starch-based films in the food industry is preferable due to their biocompatibility and biodegradability characteristics.
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Nariz Eletrônico , Embalagem de Alimentos , Amido , Amido/química , Animais , Galinhas , Suínos , Bovinos , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/análise , Smartphone , Análise de Componente PrincipalRESUMO
Plasmodium, a digenetic parasite, requires a host and a vector for its life cycle completion. Most Plasmodium species display circadian rhythmicity during their intraerythrocytic cycle within the host, aiding in immune evasion. This rhythmicity, however, diminishes in in vitro cultures, highlighting the importance of host-derived signals for synchronizing the parasite's asexual cycle. Studies indicate a species-specific internal clock in Plasmodium, dependent on these host signals. Melatonin, a hormone the pineal gland produces under circadian regulation, impacts various physiological functions and is extensively reviewed as the primary circadian marker affecting parasite rhythms. Research suggests that melatonin facilitates synchronization through the PLC-IP3 signaling pathway, activating phospholipase C, which triggers intracellular calcium release and gene expression modulation. This evidence strongly supports the role of melatonin as a key circadian marker for parasite synchronization, presenting new possibilities for targeting the melatonin pathway when developing novel therapeutic approaches.
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Ritmo Circadiano , Melatonina , Plasmodium , Melatonina/metabolismo , Ritmo Circadiano/fisiologia , Animais , Humanos , Plasmodium/metabolismo , Plasmodium/fisiologia , Malária/parasitologia , Malária/metabolismo , Biomarcadores , Transdução de Sinais , Interações Hospedeiro-ParasitaRESUMO
The technological revolution has contributed to environmental and social issues around the world. However, in the context of higher education institutions (HEIs) - key stakeholders for sustainable development - there is a theoretical gap regarding systematic reviews on the topic. In order to address this need, this study explores how digital transformation (DT) can contribute to sustainability in HEIs by identifying the general state of the art, the theoretical perspectives in the field, and future research insights. A multi-methods approach was adopted, which consisted of a quantitative bibliometric review and a qualitative content analysis. Consistent with this approach, the Scopus database was used for the bibliometric analysis of 672 publications, which was conducted with the support of VOSviewer software. Subsequently, a content analysis of 72 publications was carried out using the software ATLAS.ti and Zotero. The findings suggest three areas of current research: ensuring sustainability competencies through DT, smart and sustainable campus approaches, and theorisation of sustainability in higher education through DT. The theoretical perspectives of the field were divided and discussed into seven main clusters. Lastly, five research lines for further studies on DT towards sustainability were identified. This study has both theoretical and practical implications since it may be the first literature review on this subject, providing theoretical insights to the academic community, guiding sustainability and digital practices in HEIs - through the identification of tools, approaches, and strategies - and then supporting the implementation of the United Nations Sustainable Development Goals.
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Melatonin and its indoles derivatives are central in the synchronization of malaria parasites. In this research, we discovered that melatonin is unable to increase the parasitemia in the human malaria Plasmodium falciparum that lacks the kinase PfeIK1. The PfeIK1 knockout strain is a valuable tool in the screening of indol-related compound that blocks the melatonin effect in wild-type (WT) parasite development. The assays were performed by using flow cytometry with simultaneous labeling for mitochondria viability with MitoTracker Deep Red and nucleus staining with SYBR Green. We found that Melatotosil leads to an increase in parasitemia in P. falciparum and blocks melatonin effect in the WT parasite. Using microscopy imaging system, we found that Melatotosil at 500 nM is able to induce cytosolic calcium rise in transgenic PfGCaMP3 parasites. On the contrary, the compound Triptiofen blocks P. falciparum cell cycle with IC50 9.76 µM ± 0.6, inhibits melatonin action, and does not lead to a cytosolic calcium rise in PfGCaMP3 parasites. We also found that the synthetic indol-related compounds arrested parasite cycle for PfeIK1 knockout and (WT) P. falciparum (3D7) in 72 hours culture assays with the IC50 values slighting lower for the WT strain. We concluded that the kinase PfeIK1 is central for melatonin downstream signaling pathways involved in parasite cell cycle progression. More importantly, the indol-related compounds block its cycle as an upstream essential mechanism for parasite survival. Our data clearly show that this class of compounds emerge as an alternative for the problem of resistance with the classical antimalarials.
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Antimaláricos/farmacologia , Ciclo Celular , Malária Falciparum/enzimologia , Plasmodium falciparum/enzimologia , Transdução de Sinais , Proteínas Elk-1 do Domínio ets/antagonistas & inibidores , Antimaláricos/química , Humanos , Malária Falciparum/tratamento farmacológico , Melatonina , Proteínas Elk-1 do Domínio ets/metabolismoRESUMO
BACKGROUND: Early pregnancy ultrasound scans are usually performed by nonexpert examiners in obstetrics/gynecology (OB/GYN) emergency departments. Establishing the precise diagnosis of pregnancy location is key for appropriate management of early pregnancies, and experts are usually able to locate a pregnancy in the first scan. A decision-support system based on a semantic, expert-validated knowledge base may improve the diagnostic performance of nonexpert examiners for early pregnancy transvaginal ultrasound. OBJECTIVE: This study aims to evaluate a novel Intelligent Scan Assistant System for early pregnancy ultrasound to diagnose the pregnancy location and determine the image quality. METHODS: Two trainees performed virtual transvaginal ultrasound examinations of early pregnancy cases with and without the system. The ultrasound images and reports were blindly reviewed by two experts using scoring methods. A diagnosis of pregnancy location and ultrasound image quality were compared between scans performed with and without the system. RESULTS: Each trainee performed a virtual vaginal examination for all 32 cases with and without use of the system. The analysis of the 128 resulting scans showed higher quality of the images (quality score: +23%; P<.001), less images per scan (4.6 vs 6.3 [without the CDSS]; P<.001), and higher confidence in reporting conclusions (trust score: +20%; P<.001) with use of the system. Further, use of the system cost an additional 8 minutes per scan. We observed a correct diagnosis of pregnancy location in 39 (61%) and 52 (81%) of 64 scans in the nonassisted mode and assisted mode, respectively. Additionally, an exact diagnosis (with precise ectopic location) was made in 30 (47%) and 49 (73%) of the 64 scans without and with use of the system, respectively. These differences in diagnostic performance (+20% for correct location diagnosis and +30% for exact diagnosis) were both statistically significant (P=.002 and P<.001, respectively). CONCLUSIONS: The Intelligent Scan Assistant System is based on an expert-validated knowledge base and demonstrates significant improvement in early pregnancy scanning, both in diagnostic performance (pregnancy location and precise diagnosis) and scan quality (selection of images, confidence, and image quality).
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Sistemas de Apoio a Decisões Clínicas/normas , Ultrassonografia/métodos , Diagnóstico Precoce , Feminino , Humanos , GravidezRESUMO
Alzheimer's disease is the most common neurodegenerative disease, and its treatment is lacking. In this work, we tested Amylovis-201, a naphthalene-derived compound, as a possible therapeutic candidate for the treatment of AD. For this purpose, we performed three experiments. In the first and third experiment, animals received a bilateral administration of streptozotocin and, starting 24 h after injection, a daily dose of Amylovis-201 (orally), for 17 days or for the whole time of the experiment respectively (28 days), after which learning and memory, as well as the number of hippocampal dentate gyrus cells, were assessed. In the second experiment, healthy animals received a single dose of Amylovis-201, 10 min or 5 h after the learning section to assess whether this substance could promote specific mechanisms involved in memory trace formation. Our data show that, administration of a single dose of Amylovis-201, 10 min after the end of training, but not at 5 h, produces a prolongation in memory duration, probably because it modulates specific mechanisms involved in memory trace consolidation. Furthermore, daily administration of Amylovis-201 to animals with bilateral intracerebroventricular injection of STZ produces a reduction in the loss of the hippocampus dentate gyrus cells and an improvement in spatial memory, probably because Amylovis-201 can interact with some of the protein kinases of the insulin signaling cascade, also involved in neural plasticity, and thereby halt or reverse some of the effects of STZ. Taking to account these results, Amylovis-201 is a good candidate for the therapeutic treatment of AD.
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Doença de Alzheimer , Doenças Neurodegenerativas , Animais , Estreptozocina/farmacologia , Doenças Neurodegenerativas/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Memória Espacial , Transtornos da Memória/metabolismo , Aprendizagem em LabirintoRESUMO
Essential oils are appreciated worldwide for their pleasant aroma, in addition to their therapeutic, pharmacological, and cosmetic functions. For these reasons, adulteration is a common practice that decreases product quality causing economic and health issues. In this study, we present for the first time the application of a simple, inexpensive and disposable paper-based optoelectronic nose (i.e. colorimetric sensor array) to (i) discriminate sixteen different types of essential oils and (ii) detect adulterated samples. The colorimetric array was prepared by adding 1.5 µL of 9 chemo-responsive dyes with different chemical properties to each circular spot of the paper-based device. 1 mL of each essential oil was transferred to a flask and bubbled with synthetic air at an airflow of 200 mL min-1. Then, the optoelectronic nose was exposed to the airstream containing the volatiles from the sample for 5 minutes. Digital images from before and after exposure were obtained using a smartphone and the RGB values were extracted using appropriate software. The color changes provided a unique color map fingerprint for each essential oil. Hierarchical clustering analysis (HCA) and principal component analysis (PCA) were successfully employed using a customized smartphone app, showing suitable discrimination of all studied essential oils as well as among adulterated and non-adulterated samples. The proof-of-concept showed the potential of the optoelectronic nose approach for the discrimination of different essential oils and the identification of adulterated samples, providing a valuable tool for quality control procedures.
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Objective: To analyse the factors associated with preventable of infant mortality, in Espirito Santo, Brazil. Methods: Data were collected from records of notifiable of infant death of the Mortality Information System. A total of 5,089 infant deaths were classified as preventable and non-preventable according to the International Collaborative Effort on Infant Mortality (ICE) and the State System of Data Analysis Foundation (SEADE) methods. To investigate the factors associated with preventable of deaths, it was applied the logistic regression. Results: Approximately, 73% of the deaths were preventable according to the ICE, while 76% were preventable according to the SEADE method. Using to both methods, it was observed that preterm birth, postneonatal death and birth weight between 3000 and above 4,000 g represented higher chances for preventable infant deaths. Furthermore, the medical care was more likely to preventable infant death only for ICE method. Conclusions: The factors related to the quality of care offered in the prenatal, prepartum and childbirth periods were more relevant for the occurrence of preventable infant death. Accordingly, it is recommended to strengthen mother-child care to detect risk pregnancies during prenatal care, as well as a hierarchical, regionalized and integrated perinatal network.
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This study aimed to describe cesarean and repeated cesarean section rates in Brazil according to gestational age (GA) at birth and type of hospital. This is an ecologic study using data from the Brazilian Information System on Live Births and the 2017 National Registry of Health Facilities. Overall and repeated cesarean section rates were calculated and analyzed according to GA, region of residence, and type of hospital. Spearman correlations were performed between cesarean and repeated cesarean section rates by GA subgroups at birth (≤ 33, 34-36, 37-38, 39-41, and ≥ 42 weeks) and analyzed according to the type of hospital. Overall and repeated cesarean section rates were 55.1% and 85.3%, respectively. More than 60% of newborns between 37-38 weeks were delivered via cesarean section. Private hospitals in all regions showed the highest cesarean section rates, especially those in the Central-West Region, with more than 80% at all GAs. The overall cesarean section rate was highly correlated with all cesarean section rates of GA subgroups (r > 0.7, p < 0.01). Regarding repeated cesarean sections, the overall rate was strongly correlated with the rates of 37-38 and 39-41 weeks in public/mixed hospitals, differing from private hospitals, which showed moderate correlations. This finding indicates the decision for cesarean section is not based on clinical factors, which can cause unnecessary damage to the health of both the mother and the baby. Then, changes in the delivery care model, strengthening public policies, and encouragement of vaginal delivery after a cesarean section in subsequent pregnancies are important strategies to reduce cesarean section rates in Brazil.
O objetivo deste estudo foi descrever as taxas de cesariana e cesariana recorrente no Brasil segundo a idade gestacional (IG) ao nascer e o tipo de hospital. Trata-se de um estudo ecológico, utilizando dados do Sistema de Informação sobre Nascidos Vivos e do Cadastro Nacional de Estabelecimentos de Saúde de 2017. As taxas de cesariana geral e recorrente foram calculadas e analisadas de acordo com a IG, região de residência e tipo de hospital. Foram realizadas correlações de Spearman entre as taxas de cesariana e cesariana recorrente por subgrupos de IG ao nascer (≤ 33, 34-36, 37-38, 39-41 e ≥ 42 semanas), analisadas segundo o tipo de hospital. Verificaram-se taxas de cesariana geral e recorrente de 55,1% e 85,3%, respectivamente. Mais de 60% dos recém-nascidos entre 37-38 semanas ocorreram via cesariana. Os hospitais privados de todas as regiões concentraram as maiores taxas de cesariana, sobretudo os do Centro-oeste, com mais de 80% em todas as IG. A taxa geral de cesariana foi altamente correlacionada com todas as taxas de cesariana dos subgrupos de IG (r > 0,7, p < 0,01). Quanto à cesariana recorrente, verificou-se forte correlação com as taxas de 37-38 e 39-41 semanas no hospital público/misto, diferindo do hospital privado, que apresentou correlações moderadas. Isso indica que a decisão pela cesariana não é pautada em fatores clínicos, o que pode causar danos desnecessários à saúde da mulher e do bebê. Conclui-se que mudanças no modelo de atenção ao parto, fortalecimento de políticas públicas e maior incentivo do parto vaginal após cesárea em gestações subsequentes são estratégias importantes para a redução das cesarianas no Brasil.
El objetivo de este estudio fue describir las tasas de cesárea y de cesárea recurrente en Brasil según la edad gestacional (EG) al nacer y el tipo de hospital. Estudio ecológico a partir de los datos del Sistema de Información de Nacidos Vivos y del Registro Nacional de Establecimientos de Salud 2017. Se calcularon y analizaron las tasas de cesárea general y recurrente según EG, región de residencia y tipo de hospital. Se aplicaron las correlaciones de Spearman entre las tasas de cesárea y de cesárea recurrente por subgrupos de EG al nacer (≤ 33, 34-36, 37-38, 39-41 y ≥ 42 semanas) y se analizaron según el tipo de hospital. Las tasas de cesárea general y recurrente fueron del 55,1% y 85,3%, respectivamente. Más del 60% de los recién nacidos entre 37-38 semanas nacieron por cesárea. Los hospitales privados de todas las regiones concentraron las tasas más altas de cesáreas, especialmente los del Centro-Oeste, con más del 80% en todas las EG. En general, la tasa general de cesáreas estuvo altamente correlacionada con todas las tasas de cesáreas de los subgrupos de EG (r > 0,7, p < 0,01). En cuanto a la cesárea recurrente, se encontró que la tasa general se correlacionó fuertemente con las tasas de 37-38 y 39-41 semanas en el hospital público/mixto, a diferencia del hospital privado que mostró correlaciones moderadas. Esto indica que la decisión de hacer la cesárea no se basa en factores clínicos, lo que puede causar daños innecesarios a la salud de la mujer y del bebé. Por lo tanto, los cambios en el modelo de asistencia al parto, el fortalecimiento de las políticas públicas y una mayor promoción del parto vaginal en los embarazos posteriores de la cesárea se encuentran entre las estrategias importantes para reducir esta práctica en Brasil.
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Cesárea , Parto , Brasil/epidemiologia , Feminino , Idade Gestacional , Hospitais Privados , Humanos , Recém-Nascido , GravidezRESUMO
OBJECTIVE: Describe and estimate the rate of recurrent preterm birth in Brazil according to the type of delivery, weighted by associated factors. METHODS: We obtained data from the national hospital-based study "Birth in Brazil", conducted in 2011 and 2012, from interviews with 23,894 women. Initially, we used the chi-square test to verify the differences between newborns according to previous prematurity and type of recurrent prematurity. Sequentially, we applied the propensity score method to balance the groups according to the following covariates: maternal age, socio-economic status, smoking during pregnancy, parity, previous cesarean section, previous stillbirth or neonatal death, chronic hypertension and chronic diabetes. Finally, we performed multiple logistic regression to estimate the recorrence. RESULTS: We analyzed 6,701 newborns. The rate of recurrence was 42.0%, considering all women with previous prematurity. Among the recurrent premature births, 62.2% were spontaneous and 37.8% were provider-initiated. After weighting by propensity score, we found that women with prematurity have 3.89 times the chance of having spontaneous recurrent preterm birth (ORaj = 3.89; 95%CI 3.01-5.03) and 3.47 times the chance of having provider-initiated recurrent preterm birth (ORaj = 3.47; 95%CI 2.59-4.66), compared to women who had full-term newborns. CONCLUSIONS: Previous prematurity showed to be a strong predictor for its recurrence. Thus, expanding and improving the monitoring and management of pregnant women who had occurrence of prematurity strongly influence the reduction of rates and, consequently, the reduction of infant morbidity and mortality risks in the country.
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Nascimento Prematuro , Brasil/epidemiologia , Cesárea , Feminino , Humanos , Recém-Nascido , Paridade , Parto , Gravidez , Nascimento Prematuro/epidemiologiaRESUMO
OBJECTIVE: To verify whether advanced maternal age (AMA), defined as women of ≥35 years, is associated with premature and early-term birth in Brazil, according to the onset of labor (spontaneous or provider-initiated). METHODS: Cross-sectional population-based study. The "Birth in Brazil" study interviewed 23 894 puerperal women between 2011 and 2012, in all regions of Brazil. The current analysis included 17 994 adult mothers and their newborns (15 448 aged between 20-34 years, and 2536 ≥ 35 years). A propensity score was used to assess the likelihood of AMA women giving birth to premature or early-term infants (spontaneous or provider-initiated) compared to women aged 20-34 years. To balance the groups, we used maternal, prenatal, and childbirth characteristics. RESULTS: The general prematurity rate was 10.24%, of which the majority of births were spontaneous (55.73%). Conversely, early-term births were more often provider-initiated (54.81%). AMA did not increase the chance of premature births, whether spontaneous or provider-initiated. However, AMA was associated with a higher rate of provider-initiated early-term birth (OR = 1.48; 95% CI: 1.23-1.77). CONCLUSION: AMA alone does not contribute to premature birth; AMA's independent association with provider-initiated early-term birth may not be based solely on clinical indications.
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Nascimento Prematuro , Adulto , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Idade Materna , Gravidez , Nascimento Prematuro/epidemiologia , Nascimento a Termo , Adulto JovemRESUMO
Olive oil is one of the oldest and essential edible oils in the market. The classification of olive oils (e.g. extra virgin, virgin, refined) is often influenced by factors ranging from its complex inherent physiochemical properties (e.g. fatty acid profiles) to the undisclosed manufacturing processes. Therefore, olive oils have been the target of adulteration due to its profitable margin. In this work, we demonstrate that multi-parametric time-domain NMR relaxometry can be used to rapidly (in minutes) identify and classify olive oils in label-free and non-destructive manner. The subtle differences in molecular microenvironment of the olive oils induce substantial changes in the relaxation mechanism in the time-domain NMR regime. We demonstrated that the proposed NMR-relaxation based detection (AUC = 0.95) is far more sensitive and specific than the current gold-standards in the field i.e. near-infrared spectroscopy (AUC = 0.84) and Ultraviolet-visible spectroscopy (AUC = 0.73), respectively. We further show that, albeit the inherent complexity of olive plant natural phenotypic variations, the proposed NMR-relaxation based traits may be a viable mean (AUC = 0.71) in tracing the regions of origin for olive trees, in agreement with their geographical orientation.
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Melatonin acts to synchronize the parasite's intraerythrocytic cycle by triggering the phospholipase C-inositol 1,4,5-trisphosphate (PLC-IP3) signaling cascade. Compounds with an indole scaffold impair in vitro proliferation of blood-stage malaria parasites, indicating that this class of compounds is potentially emerging antiplasmodial drugs. Therefore, we aimed to study the role of the alkyl and aryl thiol moieties of 14 synthetic indole compounds against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strains of Plasmodium falciparum. Four compounds (3, 26, 18, 21) inhibited the growth of P. falciparum (3D7) by 50% at concentrations below 20 µM. A set of 2-sulfenylindoles also showed activity against Dd2 parasites. Our data suggest that Dd2 parasites are more susceptible to compounds 20 and 28 than 3D7 parasites. These data show that 2-sulfenylindoles are promising antimalarials against chloroquine-resistant parasite strains. We also evaluated the effects of the 14 compounds on the parasitemia of the 3D7 strain and their ability to interfere with the effect of 100 nM melatonin on the parasitemia of the 3D7 strain. Our results showed that compounds 3, 7, 8, 10, 14, 16, 17, and 20 slightly increased the effect of melatonin by increasing parasitemia by 8-20% compared with that of melatonin-only-treated 3D7 parasites. Moreover, we found that melatonin modulates the expression of kinase-related signaling components giving additional evidence to investigate inhibitors that can block melatonin signaling.
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Malária Falciparum , Malária , Melatonina , Parasitos , Animais , Cloroquina/farmacologia , Humanos , Indóis/metabolismo , Indóis/farmacologia , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Melatonina/metabolismo , Melatonina/farmacologia , Parasitemia , Plasmodium falciparumRESUMO
BACKGROUND: Self-complementary RNA transcripts form a double-stranded RNA (dsRNA) that triggers a sequence-specific mRNA degradation, in a process known as RNA interference (RNAi), leading to gene silencing. In vascular plants, RNAi molecules trafficking occur between cells and systemically throughout the plant. RNAi signals can spread systemically throughout a plant, even across graft junctions from transgenic to non-transgenic stocks. There is also a great interest in applying RNAi to pathogenic fungi. Specific inhibition of gene expression by RNAi has been shown to be suitable for a multitude of phytopathogenic filamentous fungi. However, double-stranded (ds)RNA/small interfering (si)RNA silencing effect has not been observed in vivo. RESULTS: This study demonstrates for the first time the in vivo interference phenomenon in the pathogenic fungus Fusarium verticillioides, in which expression of an individual fungal transgene was specifically abolished by inoculating mycelial cells in transgenic tobacco plants engineered to express siRNAs from a dsRNA corresponding to the particular transgene. CONCLUSION: The results provide a powerful tool for further studies on molecular plant-microbe and symbiotic interactions. From a biotechnological perspective, silencing of fungal genes by generating siRNAs in the host provides a novel strategy for the development of broad fungi-resistance strategies in plants and other organisms.
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Fusarium/genética , Inativação Gênica , Nicotiana/genética , Plantas Geneticamente Modificadas/genética , Interferência de RNA , RNA de Cadeia Dupla/metabolismo , Northern Blotting , Southern Blotting , Primers do DNA/genética , Fusarium/ultraestrutura , Microscopia Eletrônica de Varredura , Folhas de Planta/microbiologia , Folhas de Planta/ultraestrutura , Plantas Geneticamente Modificadas/microbiologia , Reação em Cadeia da Polimerase , RNA de Cadeia Dupla/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Nicotiana/microbiologia , Transgenes/genéticaRESUMO
Natural and synthetic alkaloids are widely used for several applications, ranging from clinical purposes to criminal activities. Presumptive color tests are considered a leading tool to reveal on-scene substance identification via rapid chemical reactions that result in visual color changes. Colorimetric tests are popular due to their inherent simplicity, low cost, promptitude and portability; however, in many cases the results of such tests may not be predictable, partly because of the interference from similar species. In this proof-of-concept study, we present a paper-based microfluidic optoelectronic tongue - the so-called µOPTO - comprised of 6 indicators in lieu of one specific test and capable of discriminating 8 different alkaloid drugs (i.e. scopolamine, atropine, cocaine, morphine, ephedrine, caffeine, dipyrone and alprazolam) used for recreational, criminal and medical purposes. The wax printing method was employed to fabricate the microfluidic analytical device with six circular spots for reagent accommodation connected to a centered spot to enable simultaneous reactions with one sample injection. Digital images were obtained using an ordinary flatbed scanner, and the RGB information from before and after sample exposure was extracted using appropriate software. The color changes related to each spot were used to build differential maps with a unique fingerprint for each drug. The chemometric tools (i.e. PCA and HCA) showed suitable discrimination of all studied alkaloids in different quantities. To demonstrate a practical application, different alcoholic beverages spiked with scopolamine - a famous substance that causes drug abuse - were analyzed using the optoelectronic tongue. The results showed that small quantities of the drug were identified in different beverages, demonstrating that our device has the potential to be used in situ to prevent ingestion of contaminated samples.
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Cocaína , Preparações Farmacêuticas , Colorimetria , Microfluídica , LínguaRESUMO
Previously we have reported that the G protein-coupled receptor (GPCR)-like PfSR25 in Plasmodium falciparum is a potassium (K+) sensor linked to intracellular calcium signaling and that knockout parasites (PfSR25-) are more susceptible to oxidative stress and antimalarial compounds. Here, we explore the potential role of PfSR25 in susceptibility to the antimalarial compounds atovaquone, chloroquine, dihydroartemisinin, lumefantrine, mefloquine, piperaquine, primaquine, and pyrimethamine and the Medicine for Malaria Venture (MMV) compounds previously described to act on egress/invasion (MMV006429, MMV396715, MMV019127, MMV665874, MMV665878, MMV665785, and MMV66583) through comparative assays with PfSR25- and 3D7 parasite strains, using flow cytometry assays. The IC50 and IC90 results show that lumefantrine and piperaquine have greater activity on the PfSR25- parasite strain when compared to 3D7. For MMV compounds, we found no differences between the strains except for the compound MMV665831, which we used to investigate the store-operated calcium entry (SOCE) mechanism. The results suggest that PfSR25 may be involved in the mechanism of action of the antimalarials lumefantrine and piperaquine. Our data clearly show that MMV665831 does not affect calcium entry in parasites after we depleted their internal calcium pools with thapsigargin. The results demonstrated here shed light on new possibilities on the antimalarial mechanism, bringing evidence of the involvement of the GPCR-like PfSR25.
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â¢Discuss molecular components for the coordination of circadian rhythm of malaria parasites inside the vertebrate host.â¢Synthetic indole compounds show antimalarial activity in vitro against P.falciparum 3D7.â¢Plasmodium falciparum synchronizes in cell culture upon melatonin treatment.
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The host hormone melatonin is known to modulate the asexual cell-cycle of the human malaria parasite Plasmodium falciparum and the kinase PfPK7 is fundamental in the downstream signaling pathways. The nuclear protein PfMORC displays a histidine kinase domain and is involved in parasite cell cycle control. By using a real-time assay, we show a 24 h (h) rhythmic expression of PfMORC at the parasite asexual cycle and the expression is dramatically changed when parasites were treated with 100 nM melatonin for 17 h. Moreover, PfMORC expression was severely affected in PfPK7 knockout (PfPK7-) parasites following melatonin treatment. Parasites expressing 3D7morc-GFP shows nuclear localization of the protein during the asexual stage of parasite development. Although the PfMORC knockdown had no significant impact on the parasite proliferation in vitro it significantly changed the ratio of the different asexual intraerythrocytic stages of the parasites upon the addition of melatonin. Our data reveal that in addition to the upstream melatonin signaling pathways such as IP3 generation, calcium, and cAMP rise, a nuclear protein, PfMORC is essential for the hormone response in parasite synchronization.
Assuntos
Malária Falciparum/genética , Proteínas Nucleares/genética , Plasmodium falciparum/genética , Animais , Eritrócitos/parasitologia , Humanos , Malária Falciparum/parasitologia , Melatonina/genética , Plasmodium falciparum/patogenicidade , Proteínas de Protozoários/genética , Reprodução Assexuada/genéticaRESUMO
Olive oil is an appreciated food product with high nutritional value, besides being an essential component in many culture diets. In this study, we present for the first time the application of a simple and non-invasive paper-based optoelectronic nose designed in a QR code configuration to evaluate the odor of olive oils. The chemical QR code was fabricated by the addition of 12 dyes, which provided high dimensional data resulting from the interaction between the volatile compounds and the colorimetric array. The color changes were employed to build differential maps with a unique fingerprint (i) to discriminate between olive oil and other edible oil samples; (ii) to quantify nonanaldehyde as an oxidation marker; and (iii) to identify oxidized oils through principal component analysis (PCA) and hierarchical component analysis (HCA). By developing suitable mobile apps, we anticipate the employment of the chemical QR code for portable, low-cost, and in-situ evaluation of food product quality.