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Autophagic flux plays a crucial role in various diseases. Recently, the lysosomal ion channel TRPML1 has emerged as a promising target in lysosomal storage diseases, such as mucolipidosis. The discovery of mucolipin synthetic agonist-1 (ML-SA1) has expanded our understanding of TRPML1's function and its potential therapeutic uses. However, ML-SA1 is a racemate with limited cellular potency and poor water solubility. In this study, we synthetized rac-ML-SA1, separated the enantiomers by chiral liquid chromatography and determined their absolute configuration by vibrational circular dichroism (VCD). In addition, we focused on investigating the impact of each enantiomer of ML-SA1 on the TRPML1-TFEB axis. Our findings revealed that (S)-ML-SA1 acts as an agonist for TRPML1 at the lysosomal membrane. This activation prompts transcription factor EB (TFEB) to translocate from the cytosol to the nucleus in a dose-dependent manner within live cells. Consequently, this signaling pathway enhances the expression of coordinated lysosomal expression and regulation (CLEAR) genes and activates autophagic flux. Our study presents evidence for the potential use of (S)-ML-SA1 in the development of new therapies for lysosomal storage diseases that target TRPML1.

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Introdução: Os arcos branquiais são os precursores embriológicos da face, pescoço e faringe. As anomalias dos arcos branquiais são a segunda lesão congênita mais comum de cabeça e pescoço em crianças. Entre essas anomalias, estão os cistos de arcos branquiais (BCC), que surgem devido a uma incorreta obliteração das fendas branquiais, ainda no período embrionário. Os BCC podem ser assintomáticos, apenas percebidos incidentalmente, e não se manifestar até a idade adulta. Resultados: Anomalias do segundo arco branquial devem ser consideradas como um dos possíveis diagnósticos diferenciais de massas cervicais, especialmente as que se manifestam como um abaulamento em região lateral do pescoço. Os BCC são formações de revestimento epitelial, sem aberturas externas. Após seu diagnóstico, o tratamento é cirúrgico, usualmente por meio de uma incisão cervical transversa e cuidadosa dissecação das estruturas, com o objetivo de extirpar toda a lesão. Conclusão: O método descrito, de excisão da lesão, por meio de incisão transversa em região cervical, dissecção tecidual por planos e ressecção de massa cística, é uma opção para o tratamento dessa deformidade, com adequado resultado estético e boa reprodutibilidade.

Introduction: The branchial arches are the embryological precursors of the face, neck, and pharynx. Branchial arch anomalies are the second most common congenital head and neck lesions in children. Among these anomalies are branchial arch cysts (BCC), which arise due to incorrect obliteration of the branchial slits, still in the embryonic period. BCCs may be asymptomatic, only noticed incidentally, and not manifest until adulthood. Results: Anomalies of the second branchial arch should be considered as one of the possible differential diagnoses of neck masses, especially those that manifest as a bulge in the lateral region of the neck. BCCs are epithelial lining formations without external openings. After diagnosis, treatment is surgical, usually through a transverse cervical incision and careful dissection of the structures, with the aim of extirpating the entire lesion. Conclusion: The method described of excision of the lesion through a transverse incision in the cervical region, tissue dissection in planes, and resection of the cystic mass is an option for the treatment of this deformity, with adequate aesthetic results and good reproducibility.

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Crosslinking mass spectrometry (XL-MS) is a valuable technique for generating point-to-point distance measurements in protein space. However, cell-based XL-MS experiments require efficient software that can detect crosslinked peptides with sensitivity and controlled error rates. Many algorithms implement a filtering strategy designed to reduce the size of the database prior to mounting a search for crosslinks, but concern has been expressed over the possibility of reduced sensitivity using these strategies. We present a new scoring method that uses a rapid presearch method and a concept inspired by computer vision algorithms to resolve crosslinks from other conflicting reaction products. Searches of several curated crosslink datasets demonstrate high crosslink detection rates, and even the most complex proteome-level searches (using cleavable or noncleavable crosslinkers) can be completed efficiently on a conventional desktop computer. The detection of protein-protein interactions is increased twofold through the inclusion of compositional terms in the scoring equation. The combined functionality is made available as CRIMP 2.0 in the Mass Spec Studio.

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ETHNOBOTANICAL RELEVANCE: Equisetum hyemale is used in traditional medicine as an anti-inflammatory, antioxidant, diuretic and anticancer agent. Recent studies have observed antiproliferative activity of this species in some tumor cell lines. AIM OF THE STUDY: The aim of this study was to evaluate the antiproliferative activity of the ethanol extract of E. hyemale and its partitions in oral squamous carcinoma cell lines, the death pathways induced by the most active partition, the acute toxicity and therapeutic activity, and the identification of the main compounds. MATERIALS AND METHODS: The ethanol crude extract was prepared from the stems of E. hyemale and partitions were obtained from this extract with n-hexane, dichloromethane and ethyl acetate. Cytotoxicity assays were performed using MTT on human oral tumor lines SCC-9, SCC4 and SCC-25, and normal primary fibroblasts. The main pathways of programmed cell death were analyzed. Acute toxicity in mice was performed using the most active partition, ethyl acetate. Antitumor activity was accessed in xenotransplants grafts of SCC-9 cells in Balb/nude mice. Phytochemical analysis was performed using UHPLC-MS/MS and dereplication was done using Global Natural Product Social Molecular Networking (GNPS) analysis. RESULTS: Ethanol extract, n-hexane and ethyl acetate partitions showed dose-dependent activity and selectivity towards oral tumor cells, with the ethyl acetate being the most bioactive. This medium polarity partition was shown to induce tumor cell death through apoptosis due to the presence of activated caspase 3/7, DNA fragmentation, chromatin condensation and phosphatidylserine exposure. The ethyl acetate partition also produced low toxicity in mice, provoking mild hepatic changes, but without causing necrosis and significantly reduced tumors volume and weight in xenotransplants of SCC-9 cells. Phytochemical analysis allowed identification of kaempferol glycosides and cinnamic acid derivatives previously described for E. hyemale. In addition it was possible to identify 6 new non-glycolyzed flavonoids 5-Hydroxy-3',4',7,8-tetramethoxyflavone (14), 5,4'-Dihydroxy-7,8,3'-trimethoxyflavone (15), 5,7-Dihydroxy-3',4'-dimethoxyflavone (16), 3',4,5,7-Tretramethoxyflavone (17), 5-Hydroxy-3'4',7-trimethoxyflavone (18), and 5,4'-Dihydroxy-3'-7'-dimethoxyflavone (19); besides 5 compounds already determined to be cytotoxic in other species, Isoferulic acid (1), Ferulic acid (2), Atractylenolide III (6), Dihydroxy-3',4'-dimethoxyflavone (16), and 5-Hydroxy-3'4 ',7-trimethoxyflavone (18). CONCLUSION: The results indicate that the E. hyemale extract and partitions inhibited 3 different cell lines of OSCC in a highly selective nontoxic way by inducing apoptosis of the cells. We identified 6 new non-glycosylated flavonoids and 5 other substances in this species.

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Abstract Obesity is considered a risk factor to health and besides generating metabolic and cardiovascular alterations, it is related to mechanical complications. Since stability may be altered due to anthropometric and biomechanical factors, studies investigating the relationship of excess weight on the mobility and balance of obese adults are still scarce. The research aimed to evaluate the postural balance and mobility of obese individuals who are waiting for bariatric surgery. This is a cross-sectional and descriptive study, conducted at the Hospital das Clínicas of the Universidade Federal de Pernambuco. The sample consisted of 97 individuals, 81 women, 16 men, age 38.39 ± 10.60 years and body mass index 47.5 ± 6.9 kg/m2. The Timed Up and Go test, which evaluates the mobility, resulted in 7.6 ± 1.7 seconds as the average of the longest times spent to perform the test. Regarding the evaluation of dynamic balance and mobility, it was found that the domains of anticipatory postural adjustments, necessary to prevent postural disturbances (median 5, 95%CI 5-6) and the domain of dynamic movement, which corresponds to the balance necessary to walk (median 8, 95%CI 7-9) are the most impaired in the subjects with obesity. Positive correlations were found between weight and dynamic balance. The findings indicate that excess body fat interferes with dynamic balance.

Resumo A obesidade é considerada fator de risco à saúde e além de gerar alterações metabólicas e cardiovasculares, está relacionada a complicações mecânicas. Uma vez que a estabilidade pode estar alterada em função de fatores antropométricos e biomecânicos, ainda são escassos os estudos que investigam a relação do excesso de peso sobre a modilidade e equilíbrio dos adultos obesos. A pesquisa teve como objetivo avaliar o equilíbrio postural e a mobilidade dos indivíduos com obesidade que estão aguardando a realização da Cirurgia Bariátrica. Trata-se de um estudo transversal e descritivo, realizado no Hospital das Clínicas da Universidade Federal de Pernambuco. A amostra foi composta por 97 indivíduos, sendo 81 mulheres, 16 homens, idade 38,39 ± 10,60 anos e índice de massa corporal 47,5 ± 6,9 kg/m2. O teste Timed Up and Go, que avalia a mobilidade, teve como resultado 7,6 ± 1,7 segundos como a média dos maiores tempos gastos para a execução do teste. A respeito da avaliação do equilíbrio dinâmico e da mobilidade, verificou-se que os domínios de ajustes posturais antecipatórios, necessários para prevenir perturbações posturais (mediana 5, IC95% 5-6) e o domínio de movimentação dinâmica, que corresponde ao equilíbrio necessário para a realização da marcha (mediana 8; IC95% 7-9) são os mais prejudicados nos sujeitos com obesidade avaliados. Foram constatadas correlações positiva entre peso e equilíbrio dinâmico. Os achados indicam que o excesso de gordura corporal interfere no equilíbrio dinâmico.

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Crossing and developing inbred lines have been promising options for guava breeding programs. The purpose of this study was to evaluate the genetic divergence among genotypes of S1 inbred guava families by means of the Gower's technique and the Ward-MLM methodology, to verify the correlation and relative contribution of traits, as well as to identify descriptors with minimum efficiency for this species. The experiment was implemented at the Estação Experimental da Ilha Barra do Pomba, in the municipality of Itaocara, RJ, Brazil. A randomized block design with 18 inbred families, three replicates, and ten plants per plot was used for the experimental design. After 19 months from the planting of the experiment, the 61 earliest and most productive genotypes (individual plants) were evaluated. For this purpose, 29 descriptors were evaluated, of which fifteen were qualitative and fourteen, quantitative. The characteristics required to obtain the distance matrix were analyzed based on the Gower algorithm, and a comparative cluster between the dendrograms of the morphoagronomic variables was achieved from this matrix. Lastly, the Ward-MLM procedure was applied to form the clusters of inbred families. By using all 29 descriptors, greater efficiency was achieved in cluster discrimination. Hence, according to the results identified, it is not possible to indicate minimum descriptors for the culture. Using the Ward-MLM method, the descriptors that most contributed to the divergence among the genotypes were fruit flesh mass, fruit weight, fruit diameter, fruit flesh thickness, fruit placental mass, and fruit length. The most divergent genotypes can be recommended for further crosses or self-pollinations to develop new lines in the guava breeding program of UENF.

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Herein, the extraction of bioactive compounds from umbu fruit peel was optimized using thermal-assisted solid-liquid extraction. In parallel, antioxidant, antimicrobial, and inhibitory effects against α-amylase of optimized extract were also evaluated. The combination of operational conditions including the temperature (32-74 °C), ethanol concentration (13-97%), and solid/liquid ratio (1:10-1:60; w/v) was employed using a rotational central composite design for optimization. The extracts were evaluated for total phenolic compounds (TPC), total flavonoid compounds (TFC) and antioxidant capacity by ABTS•+, DPPH• and FRAP assays. The bioactive profile of the optimized extract was obtained by ultra-performance liquid chromatography coupled to quadrupole/time-of-flight mass spectrometry in electrospray ionization in both negative and positive modes. The statistically evaluated results showed that the optimal operational conditions for the recovery of bioactive compounds from umbu fruit peel included 74 °C, 37% ethanol, and a solid-liquid ratio of 1:38. Under these conditions, the obtained values were 1985 mg GAE/100 g, 1364 mg RE/100 g, 122 µmol TE/g, 174 µmol/TE g and 468 µmol Fe2+/g for TPC, TFC, ABTS•+, DPPH•, and FRAP assays, respectively. In addition, the optimized extract was effective against Gram-positive and Gram-negative bacteria (MBC ranged from 0.060 to 0.24 mg GAE/mL), as well as it was effective to inhibit α-amylase (IC50 value of 0.076 mg GAE/mL). The optimized extract showed to be mainly constituted by phenolic acids and flavonoids.

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INTRODUCTION: Chronic subdural haematoma (CSDH) is one of the most common neurosurgical pathologies. The recurrence of chronic subdural haematomas is an important concern, considering that elderly patients are the most affected and reoperations in these patients may represent a risk of neurological and clinical complications. In accordance with the inflammatory theory regarding CSDH and its recurrence, we aimed to evaluate the role of an inflammatory marker, neutrophil-to-lymphocyte ratio (NLR), as a risk factor and prognostic variable for CSDH recurrence. METHODS: We performed a cohort study of adult patients operated for post-traumatic CSDH traumatic CSDH between January 2015 and December 2019 in our neurotrauma unit, whose data was retrospectively retrieved. We excluded patients with previous inflammatory or infectious diseases as well as use of anticoagulant/antiplatelet medications. Neutrophil and lymphocyte counts were obtained 24 h preoperatively and 48-72 h postoperatively. The primary endpoint was symptomatic recurrence of CSDH up to 1 year after the surgery. An independent sample was used to validate the findings. RESULTS: The testing sample comprised 160 patients (59.4% male, mean age 69.3 ± 14.3 years, recurrence rate 22.5%). Postoperative neutrophil count and NLR were higher in those who recurred, as well as the neutrophils (median 1.15 vs 0.96, p = 0.022) and NLR (median 1.29 vs 0.79, p = 0.001) postoperative-to-preoperative ratios. Preoperative laboratory parameters or other baseline variables were not associated with recurrence. Postoperative NLR ratio (each additional unit, OR 2.53, 95% CI 1.37-4.67, p = 0.003) was independently associated with recurrence. The best cut-off for the postoperative NLR ratio was 0.995 (AUC-ROC 0.67, sensitivity 63.9%, specificity 76.6%). Postoperative NLR ratio ≥ 1 (i.e. a post-operative NLR that does not decrease compared to the preoperative value) was associated with recurrence (OR 4.59, 95% CI 2.00-10.53, p < 0.001). The validation sample analysis (66 patients) yielded similar results (AUC-ROC 0.728, 95% CI 0.594-0.862, p = 0.002) and similar cut-off (≥ 1.05, sensitivity 77.8%, specificity 66.7%). CONCLUSION: NLR ratio can be a useful parameter for the prediction of post-traumatic CSDH recurrence. This hypothesis was validated in an independent sample and the accuracy was moderate.

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ABSTRACT This study objective to compare the acute effects between one resistance training bout with high versus moderate intensities on inflammatory markers in women with severe obesity. Experimental crossover study, performed with adult women with severe obesity (BMI ≥ 40.0 kg/m²; age ≥ 18 years old). Each participant performed a high and moderate intensity resistance training (HIRT and MIRT, respectively) with an interval of 7 days between bouts. Four exercises were performed in the both protocols, with total training volume equalized. MIRT consisted of 3 sets of 8 repetitions each, with an intensity of 75% of 1RM, while HIRT consisted of 2 sets of 6 repetitions, followed by a 20-second rest, with a new performance of 2 to 3 repetitions, with one more rest of 20s and finishing with 2 to 3 more repetitions, at an intensity of 85% of 1RM. Blood samples were collected before, 15 minutes after and 24 hours after both training protocols. The inflammatory markers analyzed were IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ. Nine participants have completed the intervention (n=9; 35.2 ± 10.93 years old; BMI = 48.3 ± 5.06 kg/m²). The Mann-Whitney U test showed that there was no significant difference between the HIRT and MIRT in the concentration of markers. Friedman's test did not report significant differences between intragroup measures for the HIRT as well as MIRT. This research suggests that a single session of high or moderate intensity resistance training does not change the inflammatory status of women with severe obesity.

RESUMO Este estudo objetivou comparar os efeitos agudos entre uma sessão de treinamento de força de alta versus moderada intensidade sobre marcadores inflamatórios em mulheres com obesidade severa. Estudo experimental do tipo cross-over, realizado com mulheres adultas com obesidade severa (IMC ≥ 40,0 kg/m²; idade ≥ 18 anos). Cada participante realizou uma sessão de treinamento de força de alta e de moderada intensidade (HIRT e MIRT, respectivamente) com intervalo de 7 dias entre as sessões. Quatro exercícios foram realizados em ambos os protocolos, com volume total de treino equalizado. O MIRT consistiu em 3 séries de 8 repetições cada, com intensidade de 75% de 1RM, enquanto o HIRT consistiu em 2 séries de 6 repetições, seguidas de um descanso de 20 segundos, com nova execução de 2 a 3 repetições, com mais um descanso de 20s e finalização com mais 2 a 3 repetições, com intensidade de 85% de 1RM. Amostras de sangue foram coletadas antes, 15 minutos após e 24 horas após ambos os protocolos de treino. Os marcadores inflamatórios analisados foram IL-2, IL-4, IL-6, IL-10, TNF-α e IFN-γ. Nove participantes completaram a intervenção (n=9; 35,2 ± 10,93 anos; IMC = 48,3 ± 5,06 kg/m²). O teste U de Mann-Whitney mostrou que não houve diferença significativa entre HIRT e MIRT na concentração dos marcadores. O teste de Friedman não mostrou diferenças significativas entre as medidas intragrupo para HIRT e MIRT. Esta pesquisa sugere que uma única sessão de treinamento de força de alta ou moderada intensidade não altera o estado inflamatório de mulheres com obesidade severa.

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The extensive marine biodiversity has proved to be a promising source of substances with biomedical potential. In this study, the cytotoxicity of the Brazilian octocoral Phyllogorgia dilatata (Gorgoniidae) was evaluated against two tumor cell lines and three bacterial strains. The methanol/dichloromethane crude extract presented no antibacterial activity up to the highest concentration tested (512 µg/mL), however it revealed a noteworthy antiproliferative effect against HCT-116 (80%) and MCF-7 (54%) cell lines at 50 µg/mL. Therefore, guided by the cytotoxic activity, a multistep chemical fractionation of the extract provided the subfraction 5 (PDPH2-5) with IC50 values of 3.18 and 17.80 µg/mL against HCT-116 and MCF-7, respectively. The LC-HRMS/MS analysis of PDPH2-5 showed ions of m/z 219.1742 and 219.1743, characterized as (E,E) and (Z,E) germacrone, after a LC-DAD-SPE/NMR analysis of the hexanic fraction and comparisons of NMR data with the literature. Previously reported assessments to the cytotoxic activity of the (E,E)-diastereoisomer disclosed higher IC50 values than that obtained for the PDPH2-5 fraction, suggesting, herein, a potentiated effect of the diastereoisomeric mixture. Such remark encourage further bioactivity studies with stereoisomer mixtures and reduce the urge for compound isolation.

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One objective was to evaluate the association of dry matter intake as a percentage of body weight (DMI%BW) and energy balance (EB) prepartum and postpartum, and energy-corrected milk (ECM) postpatum with digestive disorders postpartum. For this, ANOVA was used, and DMI%BW, EB, and ECM were the outcome variables, and left displaced abomasum (LDA), indigestion, and other digestive disorders (ODDZ) were the explanatory variables. The main objective was to evaluate prepartum DMI%BW and EB as predictors of digestive disorders. For this, logistic regression was used, and LDA, indigestion, and ODDZ were the outcome variables and DMI%BW and EB were the explanatory variables. Data from 689 cows from 11 experiments were compiled. Left displaced abomasum was not associated with prepartum DMI%BW or EB. Postpartum data were normalized to the day of the event (day 0). Cows that developed LDA had lesser postpartum DMI%BW on days -24, -23, -12, -7 to 0 and from days 1 to 8, 10 to 12, and 14 and 16, lesser postpartum EB from days -7 to -5, -3 to 0, and 12, and lesser postpartum energy-corrected milk on days -19, -2, -1, 0, 7, 9, 10, 15, and 17 relative to diagnosis than cows without LDA. Cows that developed indigestion had lesser prepartum DMI%BW and EB than cows without indigestion, and lesser postpartum DMI%BW on days -24, -1, 0, 1, and 2, and greater DMI%BW on day 26, lesser ECM on days -24, -2, -1, 0, 1, and 2 relative to diagnosis. Postpartum EB was not associated with indigestion postpartum. Cows that developed ODDZ had lesser prepartum DMI%BW on day -8 and from days -5 to -2, lesser prepartum EB on day -8 and from days -5 to -2, and lesser postpartum DMI%BW than cows without ODDZ. Each 0.1 percentage point decrease in the average DMI%BW and each Mcal decrease in the average EB in the last 3 days prepartum increased the odds of having indigestion by 9% each. Cutoffs for DMI%BW and EB during the last 3 days prepartum to predict indigestion were established and were ≤1.3%/day and ≤0.68 Mcal/day, respectively. In summary, measures of prepartum DMI%BW and EB were associated with indigestion and ODDZ postpartum and were predictors of indigestion postpartum, although the effect sizes were small.

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Phorbas is a widely studied genus of marine sponge and produce structurally rich cytotoxic metabolites. Still, only few studies have assessed metabolites present in Brazilian species. To circumvent redundancy, in this work, we applied and herein report the use of a scouting liquid chromatographic system associate to the design of experiment produced by the DryLab® software to obtain a fast and efficient chromatographic separation of the active hexane fraction, further enabling untargeted high-resolution mass spectrometry (HRMS) data. To this end, a crude hydroalcoholic extract of the sponge Phorbas amaranthus collected in Brazilian coast was prepared and partitioned. The cytotoxicity of the crude extract and the fractions was evaluated using tumor cell culture models. Fragmentation pathways assembled from HRMS data allowed the annotation of 18 known Phorbas metabolites, while 17 metabolites were inferred based on Global Natural Product Social Molecular Networking (GNPS), matching with a further 29 metabolites annotated through molecular subnetwork. The workflow employed demonstrates that chromatographic method development can be accelerated by the use of automated scouting systems and DryLab®, which is useful for profiling natural product libraries, as well as data curation by molecular clusters and should be incorporated to the tools of natural product chemists.

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This is a case demonstrating a combined traumatic lesion of the internal carotid artery (dissection and a carotid cavernous fistula [CCF]) in a patient who was beaten during a robbery and, while trying to escape, was hit by a vehicle. Endovascular approach for the treatment was chosen using the retrograde access from the vertebral artery to the cavernous sinus by posterior communicating (Pcom) artery due to the occlusion of the ipsilateral internal carotid. Because the artery access by the internal carotid was impossible, retrograde approach by vertebral artery and Pcom artery was done to treat the direct CCF. A patient presented with left hemiplegia and proptosis, chemosis, right eye ptosis. Computed tomography (CT) and CT angiography revealed a CCF of the right carotid. An arterial retrograde endovascular approach by the vertebral artery was used for CCF occlusion with coils. We present a rare case of a combined traumatic cerebrovascular lesion, right carotid artery dissection and a right direct CCF treated by a retrograde endovascular approach by the vertebral artery through the Pcom artery to reach the fistula point and achieved a complete cure of the CCF.

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Here we describe a successful mechanical thrombectomy (MT) for acute large vessel occlusion in stroke treatment with one passage (thrombolysis in cerebral infarction, TICI 3). Immediately after the withdrawing of the stent retriever, a narrowing of the middle cerebral artery was diagnosed. The rate of vasospasms during this procedure can be as higher as 41% (range from 6-41%). Here we describe our protocol when a narrowing of the artery is visualized after a stent retriever is withdrawn. A patient presented in our emergency room with National Institute of Health Stroke Scale (NIHSS) of 21, Alberta Stroke Program Early CT Score (ASPECTS) 8, computed tomography angiography revealed occlusion of the M1 segment and MT was indicated. One passage TICI Ⅲ was achieved. After that, the image showed a narrowing of the artery. We present one case of a spasm after stent retriever technique for MT, we injected vasodilator and the artery became normal in a few minutes differentiating between atheromatous stenosis and vasospasm. We present a technical note that can help to make the differentiation of vasospasm or atheromatous disease after MT with the stent retriever technique.

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Forage crops occupy large areas of tropical pastures for cattle feeding in Brazil. The use of stylos (Stylosanthes spp.) in these pastures, which are leguminous shrubs, has increased in the country due to their outstanding nutritional value and for being an efficient and alternative source for nitrogen fixation in the soil. In recent years, virus-like mosaic symptoms on S.guianensis leaves have often been observed in the field, indicating possible virus-like pathogen infections. In an effort to identify the causal agent, virus semi-purification protocol was performed using symptomatic S. guianensis leaves collected at EMBRAPA Beef Cattle Research Center. Total RNA extracted from this semi-purified preparation was submitted to high-throughput sequencing, which revealed complete genome sequences of novel viruses of the family Potyviridae. These viruses, tentatively named stylo mosaic-associated virus 1 (StyMaV-1) and stylo mosaic-associated virus 2 (StyMaV-2), shared 73 % CP aa identity and 77 % polyprotein aa identity with each other and, after that, being closest related to blackberry virus Y, genus Brambyvirus (only 41 % CP aa identity). Based on ICTV genus demarcation criteria, StyMaV-1 and StyMaV-2 represent new species of a new genus within the family Potyviridae. StyMaV-1 and StyMaV-2 are also not efficiently transmitted to other plant species by mechanical inoculation.

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In T. cruzi, a causative agent of Chagas disease, phosphoenolpyruvate carboxykinase (TcPEPCK) is associated with carbohydrate catabolism. Due to its importance in the metabolism of the parasite, it has become a promising target for the development of new drugs against Chagas disease. Aiming to investigate different approaches for ligands screening, TcPEPCK was immobilized on amine-terminated magnetic beads (TcPEPCK-MB) and kinetically characterized by liquid chromatography tandem mass spectrometry activity assay with a KMapp value of 10 ± 1 µM to oxaloacetate as substrate. Natural products library affords highly diverse molecular frameworks through their secondary metabolites, herein a ligand fishing TcPEPCK-MB assay is described for prospecting ligands in four ethanolic extracts of Brazilian Cerrado plants: Qualea grandiflora (Vochysiaceae), Diospyros burchellii (Ebenaceae), Anadenanthera falcata (Fabaceae) and Byrsonima coccolobifolia (Malpighiaceae). The chemical characterization of eleven identified ligands was carried out by liquid chromatography tandem high-resolution mass spectrometry experiments. Senecic acid, syneilesinolide A, phytosphingosine and vanillic acid 4-glucopyranoside are herein reported for the first time for Q. grandiflora, D. burchellii, A. falcata, respectively. In addition, the specificity of the assay was observed since only catechin was fished out from the ethanolic extract of B. coccolobifolia leaves, despite the presence of epicatechin epimer.

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