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BACKGROUND: Inhibition of kinases is the ever-expanding therapeutic approach to various types of cancer. Typically, assessment of the treatment response is accomplished by standard, volumetric imaging procedures, performed weeks to months after the onset of treatment, given the predominantly cytostatic nature of the kinase inhibitors, at least when used as single agents. Therefore, there is a great clinical need to develop new monitoring approaches to detect the response to kinase inhibition much more promptly. Noninvasive 1H magnetic resonance spectroscopy (MRS) can measure in vitro and in vivo concentration of key metabolites which may potentially serve as biomarkers of response to kinase inhibition. METHODS: We employed mantle cell lymphoma (MCL) cell lines demonstrating markedly diverse sensitivity of inhibition of Bruton's tyrosine kinase (BTK) regarding their growth and studied in-depth effects of the inhibition on various aspects of cell metabolism including metabolite synthesis using metabolomics, glucose and oxidative metabolism by Seahorse XF technology, and concentration of index metabolites lactate, alanine, total choline and taurine by 1H MRS. RESULTS: Effective BTK inhibition profoundly suppressed key cell metabolic pathways, foremost pyrimidine and purine synthesis, the citrate (TCA) cycle, glycolysis, and pyruvate and glutamine/alanine metabolism. It also inhibited glycolysis and amino acid-related oxidative metabolism. Finally, it profoundly and quickly decreased concentration of lactate (a product of mainly glycolysis) and alanine (an indicator of amino acid metabolism) and, less universally total choline both in vitro and in vivo, in the MCL xenotransplant model. The decrease correlated directly with the degree of inhibition of lymphoma cell expansion and tumor growth. CONCLUSIONS: Our results indicate that BTK inhibition exerts a broad and profound suppressive effect on cell metabolism and that the affected index metabolites such as lactate, alanine may serve as early, sensitive, and reliable biomarkers of inhibition in lymphoma patients detectable by noninvasive MRS-based imaging method. This kind of imaging-based detection may also be applicable to other kinase inhibitors, as well as diverse lymphoid and non-lymphoid malignancies.
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Tirosina Quinase da Agamaglobulinemia , Linfoma de Célula do Manto , Inibidores de Proteínas Quinases , Humanos , Linhagem Celular Tumoral , Inibidores de Proteínas Quinases/farmacologia , Animais , Tirosina Quinase da Agamaglobulinemia/metabolismo , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/patologia , Linfoma de Célula do Manto/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Proliferação de Células/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos , Biomarcadores/metabolismoRESUMO
In this study, arsenic (As) speciation was investigated in the freshwater alga Chlamydomonas reinhardtii treated with 20 µg/L arsenate using fractionation as well as ICP-MS/ESI-MS analyses and was compared with the known As metabolite profile of wild-grown Saccharina latissima. While the total As accumulation in C. reinhardtii was about 85% lower than in S. latissima, the relative percentage of arsenolipids was significantly higher in C. reinhardtii (57.0% vs. 5.01%). As-containing hydrocarbons and phospholipids dominated the hydrophobic As profile in S. latissima, but no As-containing hydrocarbons were detectable in C. reinhardtii. Instead for the first time, an arsenoriboside-containing phytol (AsSugPhytol) was found to dominate the hydrophobic arsenicals of C. reinhardtii. Interestingly, this compound and its relatives had so far been only found in green marine microalgae, open sea plankton (mixed assemblage), and sediments but not in brown or red macroalgae. This compound family might therefore relate to differences in the arsenic metabolism between the algae phyla.
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Arsênio , Arsenicais , Chlamydomonas reinhardtii , Algas Comestíveis , Laminaria , Arsenicais/química , Arsênio/metabolismo , Chlamydomonas reinhardtii/metabolismo , HidrocarbonetosRESUMO
The midbrain periaqueductal grey (PAG) is a critical region for the mediation of pain-related behavioural responses. Neuronal tract tracing techniques in experimental animal studies have demonstrated that the lateral column of the PAG (lPAG) displays a crude somatotopy, which is thought to be critical for the selection of contextually appropriate behavioural responses, without the need for higher brain input. In addition to the different behavioural responses to cutaneous and muscle pain - active withdrawal versus passive coping - there is evidence that cutaneous pain is processed in the region of the lPAG and muscle pain in the adjacent ventrolateral PAG (vlPAG). Given the fundamental nature of these behavioural responses to cutaneous and muscle pain, these PAG circuits are assumed to have been preserved, though yet to be definitively documented in humans. Using ultra-high field (7-Tesla) functional magnetic resonance imaging we determined the locations of signal intensity changes in the PAG during noxious cutaneous heat stimuli and muscle pain in healthy control participants. Images were processed and blood oxygen level dependant (BOLD) signal changes within the PAG determined. It was observed that noxious cutaneous stimulation of the lip, cheek, and ear evoked maximal increases in BOLD activation in the rostral contralateral PAG, whereas noxious cutaneous stimulation of the thumb and toe evoked increases in the caudal contralateral PAG. Analysis of individual participants demonstrated that these activations were located in the lPAG. Furthermore, we found that deep muscular pain evoked the greatest increases in signal intensity in the vlPAG. These data suggest that the crude somatotopic organization of the PAG may be phyletically preserved between experimental animals and humans, with a body-face delineation capable of producing an appropriate behavioural response based on the location and tissue origin of a noxious stimulus.
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Mialgia , Substância Cinzenta Periaquedutal , Animais , Humanos , Substância Cinzenta Periaquedutal/fisiologia , Neurônios , Comportamento Animal/fisiologia , Imageamento por Ressonância MagnéticaRESUMO
The hippocampus is a brain region crucially involved in regulating stress responses and highly sensitive to environmental changes, with elevated proliferative and adaptive activity of neurons and glial cells. Despite the prevalence of environmental noise as a stressor, its effects on hippocampal cytoarchitecture remain largely unknown. In this study, we aimed to investigate the impact of acoustic stress on hippocampal proliferation and glial cytoarchitecture in adult male rats, using environmental noise as a stress model. After 21 days of noise exposure, our results showed abnormal cellular proliferation in the hippocampus, with an inverse effect on the proliferation ratios of astrocytes and microglia. Both cell lineages also displayed atrophic morphologies with fewer processes and lower densities in the noise-stressed animals. Our findings suggest that, stress not only affects neurogenesis and neuronal death in the hippocampus, but also the proliferation ratio, cell density, and morphology of glial cells, potentially triggering an inflammatory-like response that compromises their homeostatic and repair functions.
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Hipocampo , Neuroglia , Ratos , Masculino , Animais , Hipocampo/metabolismo , Neurônios/metabolismo , Astrócitos/metabolismo , Microglia/metabolismo , Neurogênese/fisiologiaRESUMO
Importance of the redox status of nicotinamide adenine dinucleotide (NAD), including its oxidized (NAD+) and reduced (NADH) forms, has been shown in many biological processes. However, NAD(H) redox status assessment is traditionally limited to biochemical assays in vitro or optical redox imaging (ORI) for superficial tissues in vivo and for deep tissues ex vivo. In recent years, phosphorous-31 magnetic resonance spectroscopy (31P-MRS) was utilized to quantify NAD+, NADH, and the redox ratio NAD+/NADH in normal tissues in vivo. The quantification is based on the spectral fitting of the upfield shoulder of the αATP peak that contains signals of NAD+ (a quartet) and NADH (a singlet), assuming pH-independence of peak positions. To evaluate the feasibility of measuring tumour NAD(H) redox status in vivo, we fitted single voxel 31P-MR spectra of subcutaneous mouse xenografts of human breast cancer cell lines acquired on a 9.4-T horizontal bore preclinical MR scanner. We found larger variations in the chemical shift offsets of NAD+ and NADH from αATP in these tumours than the literature values of normal tissues. Furthermore, our 31P-MR spectra of αATP, NAD+, and NADH solution phantoms indicated that the chemical shift of αATP and thus the offsets between NAD(H) and αATP were pH dependent. Therefore, whether tumour pH should be incorporated into the spectral fitting model should be further evaluated. Additionally, spectral resolution and signal-to-noise ratio should be improved by optimising 31P-MRS protocols, increasing data acquisition time, and using a more sensitive coil for signal detection.
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NAD , Neoplasias , Animais , Humanos , Camundongos , NAD/metabolismo , Fósforo , Estudos de Viabilidade , Espectroscopia de Ressonância Magnética/métodos , Oxirredução , Neoplasias/diagnóstico por imagemRESUMO
As a phosphorus-containing molecule, nicotinamide adenine dinucleotide is visible by phosphorus magnetic resonance spectroscopy (31P-MRS). However, the relatively low cellular levels of its oxidised (NAD+) and reduced (NADH) forms and a significant peak overlap hinder their evaluation in live tissues. This problem is critical when using 31P-MR spectroscopic imaging, where signals are localised from limited tissue volumes. We have reported improvements in spectral resolution of 31P-MRSI of human tissues in situ using a strict optimisation of the static magnetic field (B0 shimming) and 1H-irradiation during 31P acquisition. Given this, we aimed to demonstrate if these improvements allowed us to measure the in vivo intracellular levels of NAD+ and NADH at the relatively low magnetic field of 1.5 tesla (T). Our results show the feasibility of the in vivo determination of NAD+ and NADH from relatively small volumes of human tissues studied at 1.5 T. These results are clinically relevant as the currently available systems for human use mainly operate at 1.5 or 3.0.
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NAD , Fósforo , Humanos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodosRESUMO
Objective: Describe health outcomes for men based on analysis of their interrelationship with masculinities, which will make it possible to identify actions to improve health outcomes of men, women, and children. Methods: Update and expansion of the findings stated in the report on Masculinities and Health in the Region of the Americas, published by the Pan American Health Organization in 2019, which was based on a targeted, up-to-date search for secondary data on men's health and other research addressing the topic. Results: Men's and women's health is different, not only because of biological factors, but also because of gender constructs and inequalities, and the intersection of social determinants. Considerable differences are seen in mortality and morbidity patterns by sex over the life course, including men's over-mortality from preventable causes such as violent deaths, road accidents, and use of alcohol and other drugs (cocaine, cannabis, and amphetamines, among others). Several causes of mortality and morbidity are linked to expressions of the hegemonic model of masculinity, which endangers the overall health of men and people close to them. Conclusions: We propose the adoption of coordinated and intersectoral policies with a relational and intersectional gender perspective that includes men, in order to generate health actions in all policies aimed at men in all their diversity, with positive consequences as well for children, adolescents, and women.
Objetivo: Descrever os desfechos da saúde dos homens a partir da análise de sua inter-relação com as masculinidades, que permitirá identificar ações para melhorar os desfechos de saúde de homens, mulheres e crianças. Métodos: Atualização e ampliação dos achados do relatório Masculinidades e Saúde nas Américas, publicado pela Organização Pan-Americana da Saúde em 2019, que foi realizado a partir de uma busca intencional e atualizada de dados secundários sobre a saúde do homem e outras pesquisas que abordam o tema. Resultados: A saúde dos homens e das mulheres é distinta não apenas por fatores biológicos, mas também pela construção e pelas desigualdades de gênero, e pela intersecção dos determinantes sociais. Existem diferenças importantes nos padrões de morbimortalidade por sexo ao longo do curso de vida, incluindo a sobremortalidade dos homens por causas evitáveis como mortes violentas, acidentes de trânsito, e consumo de álcool e outras drogas (cocaína, cannabis e anfetaminas, entre outros). Várias causas de mortalidade e morbidade estão vinculadas à expressão do modelo hegemônico de masculinidade, que representa um risco à saúde integral dos homens e das pessoas próximas a eles. Conclusões: Propomos o desenvolvimento de políticas coordenadas e intersetoriais, com perspectiva de gênero relacional e interseccional que inclua homens, a fim de gerar ações de saúde em todas as políticas para a diversidade dos homens, com consequências positivas também para crianças, adolescentes e mulheres.
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OBJECTIVES: The aim of this study was to conduct a systematic review in order to assess the impact of early childhood caries (ECC) and its severity on Oral health-related quality of life (OHRQoL). MATERIALS AND METHODS: An electronic search was conducted in MEDLINE, EMBASE, Cochrane, SciELO and Lilacs databases. The study eligibility criteria were primary studies published in English, Spanish or Portuguese that assessed OHRQoL in preschool children with dental caries using validated instruments. Two researchers independently performed the selection process and data extraction. The Effective Public Health Practice Project's Quality Assessment Tool was used for the quality assessment. Random effects models were used to estimate the pooled effect for continuous and categorical data. RESULTS: Of 2,037 identified articles, thirty-five studies (37 articles) met the inclusion criteria. The methodological quality was judged mainly as moderate. Children with ECC were more likely to report any impact on OHRQoL than children without caries (OR: 1.99; 95% CI: 1.51-2.62; 6 studies). Severe ECC (dmft > 5) presented a higher effect (OR: 5.00; 95% CI: 3.70-6.74; 8 studies). Sensitivity analysis including only population studies showed uncertain results on the impact of ECC on OHRQoL (OR: 1.67; 95% CI: 0.99-2.82; I2 = 95%). The symptom and psychological domains were the most affected (SMD: 0.60, 95% CI: 0.38-0.81 and SMD: 0.61, 95% CI: 0.37-0.85 respectively). CONCLUSIONS: ECC has a negative impact on the OHRQoL of both preschoolers and their families. However, its impact on OHRQoL is diluted when it is evaluated at population level.
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Cárie Dentária , Qualidade de Vida , Pré-Escolar , Cárie Dentária/epidemiologia , Suscetibilidade à Cárie Dentária , Humanos , Saúde BucalRESUMO
Widespread geographic distributions in lichens have been usually explained by the high dispersal capacity of their tiny diaspores. However, recent phylogenetic surveys have challenged this assumption and provided compelling evidence for cryptic speciation and more restricted distribution ranges in diverse lineages of lichen-forming fungi. To evaluate these scenarios, we focus on the fungal genus Pseudephebe (Parmeliaceae) which includes amphitropical species, a distribution pattern whose origin has been a matter of debate since first recognized in the nineteenth century. In our study, a six-locus dataset and a broad specimen sampling covering almost all Earth's continents is used to investigate species delimitation in Pseudephebe. Population structure, gene flow and dating analyses, as well as genealogical reconstruction methods, are employed to disentangle the most plausible transcontinental migration routes, and estimate the timing of the origin of the amphitropical distribution and the Antarctic populations. Our results demonstrate the existence of three partly admixed phylogenetic species that diverged between the Miocene and Pliocene, and whose Quaternary distribution has been strongly driven by glacial cycles. Pseudephebe minuscula is the only species showing an amphitropical distribution, with populations in Antarctica, whereas the restricted distribution of P. pubescens and an undescribed Alaskan species might reflect the survival of these species in European and North American refugia. Our microevolutionary analyses suggest a Northern Hemisphere origin for P. minuscula, which could have dispersed into the Southern Hemisphere directly and/or through "mountain-hopping" during the Pleistocene. The Antarctic populations of this species are sorted into two genetic clusters: populations of the Antarctic Peninsula were grouped together with South American ones, and the Antarctic Continental populations formed a second cluster with Bolivian and Svalbard populations. Therefore, our data strongly suggest that the current distribution of P. minuscula in Antarctica is the outcome of multiple, recent colonizations. In conclusion, our results stress the need for integrating species delimitation and population analyses to properly approach historical biogeography in lichen-forming fungi.
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Especiação Genética , Líquens/classificação , Parmeliaceae/classificação , Regiões Antárticas , Ecossistema , Haplótipos/genética , Filogenia , Filogeografia , Polimorfismo Genético , Análise de Sequência de DNA , Especificidade da Espécie , Fatores de TempoRESUMO
Lichens host highly diverse microbial communities, with bacteria being one of the most explored groups in terms of their diversity and functioning. These bacteria could partly originate from symbiotic propagules developed by many lichens and, perhaps more commonly and depending on environmental conditions, from different sources of the surroundings. Using the narrowly distributed species Peltigera frigida as an object of study, we propose that bacterial communities in these lichens are different from those in their subjacent substrates, even if some taxa might be shared. Ten terricolous P. frigida lichens and their substrates were sampled from forested sites in the Coyhaique National Reserve, located in an understudied region in Chile. The mycobiont identity was confirmed using partial 28S and ITS sequences. Besides, 16S fragments revealed that mycobionts were associated with the same cyanobacterial haplotype. From both lichens and substrates, Illumina 16S amplicon sequencing was performed using primers that exclude cyanobacteria. In lichens, Proteobacteria was the most abundant phylum (37%), whereas soil substrates were dominated by Acidobacteriota (39%). At lower taxonomic levels, several bacterial groups differed in relative abundance among P. frigida lichens and their substrates, some of them being highly abundant in lichens but almost absent in substrates, like Sphingomonas (8% vs 0.2%), and others enriched in lichens, as an unassigned genus of Chitinophagaceae (10% vs 2%). These results reinforce the idea that lichens would carry some components of their microbiome when propagating, but they also could acquire part of their bacterial community from the substrates.
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Ascomicetos , Cianobactérias , Líquens , MicrobiotaRESUMO
OBJECTIVE: The objective of this work is to retrospectively analyze the resection in patients with oligometastatic stage IV pancreatic adenocarcinoma, after first-line chemotherapy for metastatic pancreatic cancer, evaluating the survival of these cases. MATERIALS AND METHODS: Between January 2005 and December 2019, 5 patients diagnosed with oligometastatic pancreatic cancer undergoing first-line chemotherapy were retrospectively evaluated, after which resective surgery was performed. RESULTS: The resective surgery performed in these patients were: three distal pancreatectomies with splenectomy, one duodenopancreatectomy and one total pancreatectomy. All received chemotherapy treatment; three patients received treatment with Folfurinox, one received 5-fluorouracil, and one received gemcitabine plus capecitabine. The patients received an average of 4 months of chemotherapy (3-6 months) and after this, resective surgery was scheduled. The average survival in these patients was 23 months (11 to 39 months), only one patient presented recurrence of the disease and died at 28 months, the remaining 4 are alive. CONCLUSION: Resective surgery in patients with stage IV pancreatic cancer can be done safely. This could be considered in selected patients with a good radiological and biochemical response after an adequate period of chemotherapy in whom there is no obvious distant disease.
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Adenocarcinoma , Neoplasias Pancreáticas , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Pancreatectomia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Estudos Retrospectivos , Neoplasias PancreáticasRESUMO
BACKGROUND: Multidisciplinary interventions may be useful for children and adolescents with diabetes mellitus (DM), especially in areas where new blood glucose monitoring and control technologies are difficult to access. METHODS: PAANDA, a care program for adolescents and children with diabetes, was implemented in patients aged 0 to 18 years and 11 months. The effect of the intervention was determined by self-blood glucose monitoring (SBGM) and glycosylated hemoglobin (HbA1C ) levels at start and after 6 months. RESULTS: A total of 121 patients with DM were evaluated, mean age of 14.27 years (SD: 4.60 years). Blood glucose measurements in range (70-120 mg/dL pre-prandial or 70-180 mg/dL post-prandial) increased by 20.67% before breakfast, 8.14% after breakfast (both P-value <.001), 5.02% before lunch (P-value = .02), 8.66% after lunch (P-value <.001), 11.50% before dinner (P-value <.001), 11.87% after dinner (P-value <.001), and 8.00% at dawn (P-value = .001). This change was accompanied by fewer values in the hyperglycemic category (-19.49% before breakfast, -7.73% after breakfast, both P-value <.001) and hypoglycemia (-1.18%). HbA1C levels decreased significantly 1.8% (P-value = .018). Multivariate logistic regression analysis showed an increase in glycemic control associated with each month after the intervention time in the PAANDA program (P-value <.001 for all the time points evaluated) and a significant decrease in glycemic variability. CONCLUSIONS: The multidisciplinary PAANDA intervention had a beneficial effect on glycemic control, with an improved time in range in a population of children and adolescents with DM.
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Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/terapia , Hemoglobinas Glicadas/metabolismo , Adolescente , Automonitorização da Glicemia , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , México , Período Pós-Prandial , Avaliação de Programas e Projetos de Saúde , Fatores de TempoRESUMO
A quantitative measurement, the Heart-to-Mediastinum (H/M) ratio of counts derived from a planar acquisition approximately 4 hours after injection of 123I-mIBG, is a strong predictor of outcomes in patients with stable class II-III heart failure and LVEF ≤ 35%. This study assessed the test-retest reproducibility of the H/M ratio in such patients. 47 subjects with class II-III systolic heart failure and LVEF ≤ 35% were tested at two time intervals separated by 5 to 14 days. Subjects were imaged twice on the same camera using the same radionuclide dose. Images were sent to a core analysis lab, where three nuclear technologists independently determined the H/M ratios. The primary endpoint was test-retest H/M ratio reproducibility calculated as the absolute difference in mean value determined by the three readers. Mean subject age was 65 ± 12 years, 85% were male, and mean BMI was 29 ± 6 kg/m2. Mean injected activity was 10.18 ± 0.43 mCi for first dose and 10.09 ± 0.52 mCi for the second dose. The mean and SD values for first and repeat studies were almost identical: the 95% confidence interval of the mean test-retest difference was 0.055 to 0.076. Bland-Altman plots showed no systematic effect of the H/M ratio on the magnitude of the difference between replicate measurements. Inter-reader measurements were nearly identical. There were no serious adverse events despite exposure to 123I-mIBG on 2 occasions in a short time period. The Heart-to-Mediastinum ratio of 123I-mIBG is a consistent and highly reproducible measurement in stable Class II to III heart failure patients.
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3-Iodobenzilguanidina/farmacologia , Coração/diagnóstico por imagem , Cintilografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Cardiomiopatias/diagnóstico por imagem , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Mediastino/patologia , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/farmacologia , Reprodutibilidade dos Testes , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular EsquerdaRESUMO
BACKGROUND: Although Latinos, African-Americans, and American Indians/Alaska Natives comprise 34% of Americans, these under-represented minorities (URMs) account for only 7% of US medical-school faculty. Even when URMs become faculty, they face many substantial challenges to success. Little has been published, however, on keys to academic success for URM young faculty investigators. METHODS: The Research in Academic Pediatrics Initiative on Diversity (RAPID) goal is to enhance the professional advancement of URM junior faculty pursuing research careers in general academic pediatrics. One important RAPID component is the annual mentoring/career-development conference, which targets URM residents, fellows, and junior faculty, and has included 62 URM participants since its 2013 inception. A conference highlight is the panel discussion on keys to academic success for URM young investigators, conducted by the RAPID National Advisory Committee, a diverse group of leading senior researchers. The article aim was to provide a guide to academic success for URM young investigators using the 2018 RAPID Conference panel discussion. A modified Delphi technique was used to provide a systematic approach to obtaining answers to six key questions using an expert panel: the single most important key to success for URM young investigators; ensuring optimal mentorship; how to respond when patients/families say, "I don't want you to see my child because you are ____"; best strategies for maximizing funding success; how to balance serving on time-consuming committees with enough time to advance research/career objectives; and the single thing you wish someone had told you which would have substantially enhanced your success early on. RESULTS/CONCLUSIONS: This is the first published practical guide on keys to academic success for URM young investigators. Identified keys to success included having multiple mentors, writing prolifically, being tenaciously persistent, having mentors who are invested in you, dealing with families who do not want you to care for their child because of your race/ethnicity by seeking to understand the reasons and debriefing with colleagues, seeking non-traditional funding streams, balancing committee work with having enough time to advance one's research and career by using these opportunities to generate scholarly products, and asking for all needed resources when negotiating for new jobs.
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Pesquisa Biomédica/organização & administração , Docentes de Medicina/estatística & dados numéricos , Mentores/estatística & dados numéricos , Grupos Minoritários/estatística & dados numéricos , Pediatria , Pesquisadores/estatística & dados numéricos , Faculdades de Medicina/organização & administração , Sucesso Acadêmico , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Pesquisa Biomédica/estatística & dados numéricos , Criança , Diversidade Cultural , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Indígenas Norte-Americanos/estatística & dados numéricos , Masculino , Faculdades de Medicina/estatística & dados numéricos , Estados Unidos , Adulto JovemRESUMO
Lichens exhibit varying degrees of specialization with regard to the surfaces they colonize, ranging from substrate generalists to strict substrate specialists. Though long recognized, the causes and consequences of substrate specialization are poorly known. Using a phylogeny of a 150-200 Mya clade of lichen fungi, we asked whether substrate niche is phylogenetically conserved, which substrates are ancestral, whether specialists arise from generalists or vice versa and how specialization affects speciation/extinction processes. We found strong phylogenetic signal for niche conservatism. Specialists evolved into generalists and back again, but transitions from generalism to specialism were more common than the reverse. Our models suggest that for this group of fungi, 'escape' from specialization for soil, rock and bark occurred, but specialization for wood foreclosed evolution away from that substrate type. In parallel, speciation models showed positive diversification rates for soil and rock dwellers but not other specialists. Patterns in the studied group suggest that fungal substrate specificity is a key determinant of evolutionary trajectory for the entire lichen symbiosis.
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Ascomicetos/fisiologia , Evolução Biológica , Líquens/fisiologia , Simbiose , FilogeniaRESUMO
BACKGROUND: Texture is a major quality parameter for the acceptability of canned whole beans. Prior knowledge of this quality trait before processing would be useful to guide variety development by bean breeders and optimize handling protocols by processors. The objective of this study was to evaluate and compare the predictive power of visible and near infrared reflectance spectroscopy (visible/NIRS, 400-2498 nm) and hyperspectral imaging (HYPERS, 400-1000 nm) techniques for predicting texture of canned black beans from intact dry seeds. Black beans were grown in Michigan (USA) over three field seasons. The samples exhibited phenotypic variability for canned bean texture due to genetic variability and processing practice. Spectral preprocessing methods (i.e. smoothing, first and second derivatives, continuous wavelet transform, and two-band ratios), coupled with a feature selection method, were tested for optimizing the prediction accuracy in both techniques based on partial least squares regression (PLSR) models. RESULTS: Visible/NIRS and HYPERS were effective in predicting texture of canned beans using intact dry seeds, as indicated by their correlation coefficients for prediction (Rpred ) and standard errors of prediction (SEP). Visible/NIRS was superior (Rpred = 0.546-0.923, SEP = 7.5-1.9 kg 100 g-1 ) to HYPERS (Rpred = 0.401-0.883, SEP = 7.6-2.4 kg 100 g-1 ), which is likely due to the wider wavelength range collected in visible/NIRS. However, a significant improvement was reached in both techniques when the two-band ratios preprocessing method was applied to the data, reducing SEP by at least 10.4% and 16.2% for visible/NIRS and HYPERS, respectively. Moreover, results from using the combination of the three-season data sets based on the two-band ratios showed that visible/NIRS (Rpred = 0.886, SEP = 4.0 kg 100 g-1 ) and HYPERS (Rpred = 0.844, SEP = 4.6 kg 100 g-1 ) models were consistently successful in predicting texture over a wide range of measurements. CONCLUSION: Visible/NIRS and HYPERS have great potential for predicting the texture of canned beans; the robustness of the models is impacted by genotypic diversity, planting year and phenotypic variability for canned bean texture used for model building, and hence, robust models can be built based on data sets with high phenotypic diversity in textural properties, and periodically maintained and updated with new data. © 2017 Society of Chemical Industry.
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Alimentos em Conserva/análise , Phaseolus/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise dos Mínimos Quadrados , Controle de Qualidade , Sementes/químicaRESUMO
As self-supporting and long-living symbiotic structures, lichens provide a habitat for many other organisms beside the traditionally considered lichen symbionts-the myco- and the photobionts. The lichen-inhabiting fungi either develop diagnostic phenotypes or occur asymptomatically. Because the degree of specificity towards the lichen host is poorly known, we studied the diversity of these fungi among neighbouring lichens on rocks in an alpine habitat. Using a sequencing metabarcoding approach, we show that lichen mycobiomes clearly reflect the overlap of multiple ecological sets of taxa, which differ in their trophic association with lichen thalli. The lack of specificity to the lichen mycobiome is further supported by the lack of community structure observed using clustering and ordination methods. The communities encountered across samples largely result from the subsampling of a shared species pool, in which we identify three major ecological components: (i) a generalist environmental pool, (ii) a lichenicolous/endolichenic pool and (iii) a pool of transient species. These taxa majorly belong to the fungal classes Dothideomycetes, Eurotiomycetes and Tremellomycetes with close relatives in adjacent ecological niches. We found no significant evidence that the phenotypically recognized lichenicolous fungi influence the occurrence of the other asymptomatic fungi in the host thalli. We claim that lichens work as suboptimal habitats or as a complex spore and mycelium bank, which modulate and allow the regeneration of local fungal communities. By performing an approach that minimizes ambiguities in the taxonomic assignments of fungi, we present how lichen mycobiomes are also suitable targets for improving bioinformatic analyses of fungal metabarcoding.
Assuntos
Ascomicetos/classificação , Basidiomycota/classificação , Código de Barras de DNA Taxonômico , Líquens/microbiologia , Micobioma , Áustria , DNA Espaçador Ribossômico/genética , Filogenia , SimbioseRESUMO
Survival of Litopenaeus vannamei was evaluated during a Vibrio parahaemolyticus infection. This bacteria has been causing significant economic losses in the shrimp industry due to the appearance of early mortality syndrome (EMS), also known as acute hepatopancreatic necrosis disease (AHPND). Control of bacteria in ponds is difficult to achieve with antibiotics due to environmental infections and antibiotic resistance. New methods have been proposed to control and prevent the impact of bacterial infections. The physiological response indicated by plasma biochemical parameters in shrimp can determine their health and stress status. Meanwhile, shrimp immunology is the key factor in establishing strategies to control diseases. Immunostimulants are the best alternative to antibiotics to prevent or minimize disease damage, and at the same time, these stimulants improve the immune system in shrimp. Four diets containing 1.5, 2, 2.5 and 3% of Dunaliella sp. with high ß-carotene content were tested in the present study. After 20days of feeding, organisms were infected with V. parahaemolyticus. Protein, glucose, lactate, triglyceride and cholesterol levels, as well as activity of prophenoloxidase and phenoloxidase, were determined 48 h post-infection (hpi). Shrimp fed a diet with 3% Dunaliella sp. showed the highest survival. Glucose, cholesterol, and triglyceride levels, as well as prophenoloxidase and phenoloxidase activity, were not observed to be suitable indicators during this bacterial infection. The results indicated that the inclusion of Dunaliella sp. in diet increases survival in L. vannamei infected with V. parahaemolyticus.
Assuntos
Clorófitas , Penaeidae/imunologia , Penaeidae/microbiologia , Vibrio parahaemolyticus , beta Caroteno/administração & dosagem , Animais , Alimentos MarinhosRESUMO
BACKGROUND: The number of racial/ethnic minority children will exceed the number of white children in the USA by 2018. Although 38% of Americans are minorities, only 12% of pediatricians, 5% of medical-school faculty, and 3% of medical-school professors are minorities. Furthermore, only 5% of all R01 applications for National Institutes of Health grants are from African-American, Latino, and American Indian investigators. Prompted by the persistent lack of diversity in the pediatric and biomedical research workforces, the Academic Pediatric Association Research in Academic Pediatrics Initiative on Diversity (RAPID) was initiated in 2012. RAPID targets applicants who are members of an underrepresented minority group (URM), disabled, or from a socially, culturally, economically, or educationally disadvantaged background. The program, which consists of both a research project and career and leadership development activities, includes an annual career-development and leadership conference which is open to any resident, fellow, or junior faculty member from an URM, disabled, or disadvantaged background who is interested in a career in academic general pediatrics. METHODS: As part of the annual RAPID conference, a Hot Topic Session is held in which the young investigators spend several hours developing a list of hot topics on the most useful faculty and career-development issues. These hot topics are then posed in the form of six "burning questions" to the RAPID National Advisory Committee (comprised of accomplished, nationally recognized senior investigators who are seasoned mentors), the RAPID Director and Co-Director, and the keynote speaker. RESULTS/CONCLUSIONS: The six compelling questions posed by the 10 young investigators-along with the responses of the senior conference leadership-provide a unique resource and "survival guide" for ensuring the academic success and optimal career development of young investigators in academic pediatrics from diverse backgrounds. A rich conversation ensued on the topics addressed, consisting of negotiating for protected research time, career trajectories as academic institutions move away from an emphasis on tenure-track positions, how "non-academic" products fit into career development, racism and discrimination in academic medicine and how to address them, coping with isolation as a minority faculty member, and how best to mentor the next generation of academic physicians.
Assuntos
Pesquisa Biomédica , Diversidade Cultural , Etnicidade , Grupos Minoritários , Pediatria , Grupos Raciais , Pesquisadores , Negro ou Afro-Americano , Escolha da Profissão , Pessoas com Deficiência , Emprego , Docentes de Medicina , Necessidades e Demandas de Serviços de Saúde , Hispânico ou Latino , Humanos , Indígenas Norte-Americanos , Mentores , Pediatras , Discriminação Social , Fatores Socioeconômicos , Estados UnidosRESUMO
KEY MESSAGE: Fivefold diversity for cooking time found in a panel of 206 Phaseolus vulgaris accessions. Fastest accession cooks nearly 20 min faster than average. SNPs associated with cooking time on Pv02, 03, and 06. Dry beans (Phaseolus vulgaris L.) are a nutrient dense food and a dietary staple in parts of Africa and Latin America. One of the major factors that limits greater utilization of beans is their long cooking times compared to other foods. Cooking time is an important trait with implications for gender equity, nutritional value of diets, and energy utilization. Very little is known about the genetic diversity and genomic regions involved in determining cooking time. The objective of this research was to assess cooking time on a panel of 206 P. vulgaris accessions, use genome- wide association analysis (GWAS) to identify genomic regions influencing this trait, and to test the ability to predict cooking time by raw seed characteristics. In this study 5.5-fold variation for cooking time was found and five bean accessions were identified which cook in less than 27 min across 2 years, where the average cooking time was 37 min. One accession, ADP0367 cooked nearly 20 min faster than average. Four of these five accessions showed close phylogenetic relationship based on a NJ tree developed with ~5000 SNP markers, suggesting a potentially similar underlying genetic mechanism. GWAS revealed regions on chromosomes Pv02, Pv03, and Pv06 associated with cooking time. Vis/NIR scanning of raw seed explained 68 % of the phenotypic variation for cooking time, suggesting with additional experimentation, it may be possible to use this spectroscopy method to non-destructively identify fast cooking lines as part of a breeding program.