RESUMO

Root-associated fungal endophytes may facilitate nitrogen (N) absorption in plants, leading to benefits in photosynthesis and growth. Here, we investigated whether endophytic insect pathogenic fungi (EIPF) are capable of transferring soil N to the crop species Chenopodium quinoa. We evaluated nutrient uptake, carbon allocation, and morpho-physiological performance in C. quinoa in symbiosis with two different EIPF (Beauveria and Metarhizium) under contrasting soil N supply. A controlled experiment was conducted using two plant groups: (1) plants subjected to low N level (5 mM urea) and (2) plants subjected to high N level (15 mM urea). Plants from each group were then inoculated with different EIPF strains, either Beauveria (EIPF1+), Metarhizium (EIPF2+) or without fungus (EIPF-). Differences in N and C content, amino acids, proteins, soluble sugars, starch, glutamine synthetase, glutamate dehydrogenase, and physiological (photosynthesis, stomatal conductance, transpiration), and morphological performance between plant groups under each treatment were examined. We found that both Beauveria and Metarhizium translocated N from the soil to the roots of C. quinoa, with positive effects on photosynthesis and plant growth. These effects, however, were differentially affected by fungal strain as well as by N level. Additionally, an improvement in root C and sugar content was observed in presence of EIPF, suggesting translocation of carbohydrates from leaves to roots. Whereas both strains were equally effective in N transfer to roots, Beauveria seemed to exert less demand in C. quinoa for photosynthesis-derived carbohydrates compared to Metarhizium. Our study revealed positive effects of EIPF on N transfer and morpho-physiological performance in crops, highlighting the potential of these fungi as an alternative to chemical fertilizers in agriculture systems.

RESUMO

This article presents a study about some perceptions of university students' perceptions in Barranquilla, Colombia about flipped classrooms during Covid-19 pandemic. The group of participants were 302 students who are studying in different universities of the city and took their virtual or remote classes with a flipped classroom strategy. Students identified their learning styles, experiences and characteristics of the virtual or remote classes and their class preferences. In addition, they mentioned resources and learning spaces used by the teachers that promote collaboration and knowledge development and technology used by the university to develop classes. Given the results of the survey, it was determined that flipped classroom strategy is a useful method for the students because it allowed them to be more self-taught (independent learning) during pandemic. It was possible to identify their learning styles and to create spaces of greater participation with the teachers as guides. Flipped classrooms allow learning by doing, developing and participating and no memorizing (traditional method) supported by emerging technologies applied in university teaching. These technologies must be combined with different strategies that allow the development of skills, teamwork and comprehension of the topics.

RESUMO

The Amazonian poison frog genus Ameerega is one of the largest yet most understudied of the brightly colored genera in the anuran family Dendrobatidae, with 30 described species ranging throughout tropical South America. Phylogenetic analyses of Ameerega are highly discordant, lacking consistency due to variation in data types and methods, and often with limited coverage of species diversity in the genus. Here, we present a comprehensive phylogenomic reconstruction of Ameerega, utilizing state-of-the-art sequence capture techniques and phylogenetic methods. We sequenced thousands of ultraconserved elements from over 100 tissue samples, representing almost every described Ameerega species, as well as undescribed cryptic diversity. We generated topologies using maximum likelihood and coalescent methods and compared the use of maximum likelihood and Bayesian methods for estimating divergence times. Our phylogenetic inference diverged strongly from those of previous studies, and we recommend steps to bring Ameerega taxonomy in line with the new phylogeny. We place several species in a phylogeny for the first time, as well as provide evidence for six potential candidate species. We estimate that Ameerega experienced a rapid radiation approximately 7-11 million years ago and that the ancestor of all Ameerega was likely an aposematic, montane species. This study underscores the utility of phylogenomic data in improving our understanding of the phylogeny of understudied clades and making novel inferences about their evolution.

Assuntos

RESUMO

BACKGROUND: Cervical cancer incidence and mortality rates in Bolivia are among the highest in Latin America. This investigation aims to evaluate the possibility of using simple devices, e.g. a cotton swab and a glass slide, for self-sampling in order to detect human papillomavirus (HPV) DNA by PCR in cervico-vaginal cells. METHODS: In the first phase of our study we evaluated the use of a glass slide as a transport medium for cervical cells. A physician took paired-cervical samples from 235 women. One sample was transported in Easyfix® solution and the other sample was smeared over a glass slide. Both were further analyzed and compared for human DNA recovery and HPV detection. A kappa value was determined to evaluate the agreement between the HPV DNA detection rates. In the second phase of the study, 222 women from the urban, peri-urban and rural regions of Cochabamba were requested to perform self-sampling using the following devices: a cotton swab combined with a glass slide, and a vaginal tampon. Women gave their opinion about the self-sampling technique. Finally, the agreement for high risk-HPV detection between self- and physician-collected samples was performed in 201 samples in order to evaluate the self-sampling technique. RESULTS: Firstly, the comparison between Easyfix® solution and the glass slide to transport clinical samples gave a good agreement for HPV DNA detection (κ = 0.71, 95% CI 0.60-0.81). Secondly, self-sampling, especially with cotton swab combined with glass slide, would generally be preferred over clinician sampling for a screening program based on HPV detection. Finally, we showed a good agreement between self- and physician collected samples for high risk-HPV detection (κ = 0.71, 95% CI 0.55-0.88). CONCLUSIONS: Simple devices such as a cotton swab and a glass slide can be used to perform self-sampling and HPV DNA detection. Furthermore, most Bolivian women preferred self-sampling over clinician-sampling for cervical cancer screening.

Assuntos

RESUMO

We describe and name a new species of poison-dart frog from the Amazonian slopes of the Andes in Manu Province, Madre de Dios Department, Peru; specifically within the Amarakaeri Communal Reserve and the buffer zone of Manu National Park. Ameerega shihuemoy sp. nov. is supported by a unique combination of characters: black dorsum with cream to light orange dorsolateral lines, blue belly reticulated with black, and the lack of axillary, thigh and calf flash marks. Within Ameerega, it shares the general appearance of A. altamazonica, A. boliviana, A. hahneli, A. ignipedis, A. petersi, A. picta, A. pongoensis, A. pulchripecta, A. simulans, A. smaragdina, and A. yungicola; each possessing a granular black to brown dorsum, a light labial bar, a conspicuous dorsolateral line running from the snout to the groin, and a metallic blue belly and underside of arms and hind limbs. From most of these species it can be distinguished by lacking flash marks on the axillae, thighs, and calves (absent in only A. boliviana and A. smaragdina, most A. petersi, and some A. pongoensis), by having bright cream to orange dorsolateral stripes (white, intense yellow, or green in all other species, with the exception of A. picta), and by its blue belly reticulated with black (bluish white and black in A. boliviana, green and blue with black marbling in A. petersi, and green and blue lacking black marbling in A. smaragdina). Its mating call also shows clear differences to morphologically similar species, with a lower note repetition rate, longer space between calls, and higher fundamental and dominant frequencies. Phylogenetic analyses based on the 16S mitochondrial rRNA fragment also support the distinctiveness of the new species and suggest that A. shihuemoy is most closely related to Ameerega macero, A. altamazonica, A. rubriventris, and two undescribed species (Ameerega sp. from Porto Walter, Acre, Brazil, and Ameerega sp. from Ivochote, Cusco, Peru). Genetically, the new species is most similar to the sympatric A. macero, from which it clearly differs in characteristics of its advertisement call and coloration. The new species is found near rocky streams during the dry season and near temporary water bodies during the rainy season. Tadpoles are found in lentic water along streams, or in shallow, slow-moving streams. Given its small geographic range, we recommend that A. shihuemoy should be considered 'Near threatened' (NT) according to IUCN Red List criteria.

Assuntos

RESUMO

BACKGROUND: The clinical significance of focal segmental glomerulosclerosis (FSGS) tip variant remains unclear. With the aim to determine its clinical and histological features, and natural history, we studied our cases of patients with this glomerular lesion. METHODS: This is a retrospective analysis. All native renal biopsies from patients diagnosed as FSGS, between 1998 and 2006, were revised for cases with tip variant. Glomerulosclerosis (GS), segmental lesions and interstitial fibrosis (IF) were quantified. We analysed clinical and follow-up data and compared with cases of FSGS not otherwise specified (NOS). RESULTS: In 248 primary FSGS cases, 37 corresponded to tip variant (14.9%). Median age was 17 years (range 1-65); 13 (35.1%) patients were <15 years old, and 56.8% were males. All patients had nephrotic proteinuria. At diagnosis, there were no significant differences for age, renal function and proteinuria between cases with NOS and tip variant. IF, GS and percentage of glomeruli with segmental lesions were higher in NOS than GTL (P < 0.01). At follow-up (n = 25), 15 patients received steroids alone, and 10 steroids and a cytotoxic agent. At a median follow-up of 48.7 months (24.3-86.7), 7 patients (28.0%) progressed to chronic kidney disease (CKD), 4 (16.0%) developed end-stage renal disease (ESRD) and 9 (36.0%) had complete remission. In NOS patients (n = 93), 48 (51.6%) developed CKD (P = 0.04), 20 (21.5%) developed ESRD (P = 0.54%) and 13 (14.0%) had complete remission (P = 0.02). CONCLUSIONS: Our work does not demonstrate a clearly favourable prognosis in a group of patients with FSGS tip variant. Although in the tip variant there are less chronic renal tissue damage and CKD, and more frequent complete remission of the nephrotic syndrome, there is an important percentage of patients who develop CKD and ESRD.

Assuntos