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Certified reference material (CRM) for natural (40K,210Pb,210Po,226Ra,228Ra,228Th,230Th,232Th,234U,235U, and238U) and anthropogenic (137Cs,239+240Pu, and241Am) radionuclides in marine sediment from the Baltic Sea (IAEA-465) has been developed. Information values are given for 238Pu,239Pu and240Pu. Altogether 27 laboratories participated in this exercise. Radiometric (alpha-spectrometry, gamma-spectrometry and beta counting, as well as mass spectrometry (ICP-MS and AMS) techniques were applied in measurements. The CRM is intended to be used for Quality Assurance/Quality Control of radionuclide analyses, for the development and validation of analytical methods, for the development of reference methods and for training purposes.
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Sedimentos Geológicos , Monitoramento de Radiação , Poluentes Radioativos da Água , Sedimentos Geológicos/química , Poluentes Radioativos da Água/análise , Plutônio/análise , Padrões de Referência , Radioisótopos/análise , Radioisótopos de Césio/análise , Tório/análiseRESUMO
Automatic tracking of viral and intracellular structures displayed as spots with varying sizes in fluorescence microscopy images is an important task to quantify cellular processes. We propose a novel probabilistic tracking approach for multiple particle tracking based on multi-detector and multi-scale data fusion as well as Bayesian smoothing. The approach integrates results from multiple detectors using a novel intensity-based covariance intersection method which takes into account information about the image intensities, positions, and uncertainties. The method ensures a consistent estimate of multiple fused particle detections and does not require an optimization step. Our probabilistic tracking approach performs data fusion of detections from classical and deep learning methods as well as exploits single-scale and multi-scale detections. In addition, we use Bayesian smoothing to fuse information of predictions from both past and future time points. We evaluated our approach using image data of the Particle Tracking Challenge and achieved state-of-the-art results or outperformed previous methods. Our method was also assessed on challenging live cell fluorescence microscopy image data of viral and cellular proteins expressed in hepatitis C virus-infected cells and chromatin structures in non-infected cells, acquired at different spatial-temporal resolutions. We found that the proposed approach outperforms existing methods.
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The top 20 highest burdened countries (in disability-adjusted life years) account for more than 75% of the global burden of viral hepatitis. An effective response in these 20 countries is crucial if global elimination targets are to be achieved. In this update of the Lancet Gastroenterology & Hepatology Commission on accelerating the elimination of viral hepatitis, we convene national experts from each of the top 20 highest burdened countries to provide an update on progress. Although the global burden of diseases is falling, progress towards elimination varies greatly by country. By use of a hepatitis elimination policy index conceived as part of the 2019 Commission, we measure countries' progress towards elimination. Progress in elimination policy has been made in 14 of 20 countries with the highest burden since 2018, with the most substantial gains observed in Bangladesh, India, Indonesia, Japan, and Russia. Most improvements are attributable to the publication of formalised national action plans for the elimination of viral hepatitis, provision of publicly funded screening programmes, and government subsidisation of antiviral treatments. Key themes that emerged from discussion between national commissioners from the highest burdened countries build on the original recommendations to accelerate the global elimination of viral hepatitis. These themes include the need for simplified models of care, improved access to appropriate diagnostics, financing initiatives, and rapid implementation of lessons from the COVID-19 pandemic.
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Gastroenterologia , Hepatite A , Hepatite , Humanos , Pandemias , Hepatite/epidemiologia , Hepatite A/epidemiologia , Hepatite A/prevenção & controle , ÍndiaRESUMO
Delayed cerebral infarction (DCI) is a major cause of morbidity and mortality in patients with aneurysmal subarachnoid hemorrhage (aSAH). The benefits of magnesium sulfate as an alternative treatment are controversial, and most previous studies examined its benefits only as adjunctive treatment to traditional nimodipine. We retrospectively analyzed aSAH patients records with magnesium sulfate between 2010 and 2021. We aimed for a serum magnesium concentration of 2-2.5 mmol/l between post-hemorrhage days 3 and 12. The patients were separated in three groups based on average serum magnesium concentration (magnesium >2 mmol/l, reduced magnesium 1.1-1.9 mmol/l, and no magnesium). Additionally, we assessed delayed cerebral infarction (DCI) and clinical outcome at follow-up, using the modified Rankin Scale (mRS), categorized in favorable (0-3) and unfavorable outcome (4-5). In this analysis, 548 patients were included. Hereof, radiological evidence of DCI could be found in 23.0% (n = 126) of patients. DCI rates were lower if patients' average serum magnesium was higher than 2 mmol/l (magnesium 18.8%, n = 85; reduced magnesium 38.3%, n = 23; no magnesium 51.4%, n = 18; p < 0.001). Also, at the last follow-up, patients in the group with a higher serum magnesium concentration had better outcome (favorable outcome: magnesium 64.7%, n = 293; reduced magnesium 50.0%, n = 30; no magnesium 34.3%, n = 12; p < 0.001). This 12-year study reveals the value of serum concentration-guided magnesium administration in aSAH patients. Our findings demonstrate the safety and efficacy when titrated to a serum concentration of 2-2.5 mmol/l. We observed higher rates of delayed cerebral infarction and unfavorable outcomes in patients with serum concentrations below 2 mmol/l.
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Magnésio , Hemorragia Subaracnóidea , Humanos , Magnésio/uso terapêutico , Sulfato de Magnésio/uso terapêutico , Estudos Retrospectivos , Hemorragia Subaracnóidea/tratamento farmacológico , Neuroproteção , Infarto CerebralRESUMO
Tuberculosis (TB) is one of the most dangerous infectious diseases and is caused by Mycobacterium bovis (Mb) and Mycobacterium tuberculosis (Mt). Branched-chain amino acid aminotransferases (BCATs) were reported to be the key enzyme for methionine synthesis in Mycobacterium. Blocking the methionine synthesis in Mycobacterium can inhibit the growth of Mycobacterium. Therefore, in silico screening of inhibitors can be a good way to develop a potential drug for treating TB. A pyridoxal 5'-phosphate (PLP)-form of Mycobacterium bovis branched-chain amino acid aminotransferases (MbBCAT), an active form of MbBCAT, was constructed manually for docking approximately 150 000 compounds and the free energy was calculated in Autodock Vina. The 10 compounds which had the highest affinity to MbBCAT were further evaluated for their inhibitory effects against MbBCAT. Within the selected compounds, compound 4 (ZINC12359007) was found to be the best inhibitor against MbBCAT with the inhibitory constant Ki of 0·45 µmol l-1 and IC50 of 2·37 µmol l-1 . Our work provides potential candidates to develop effective drugs to prevent TB since the well-known structural information would be beneficial in the structure-based modification and design.
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Mycobacterium tuberculosis , Aminoácidos de Cadeia Ramificada/farmacologia , Antituberculosos/química , Antituberculosos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Metionina/farmacologia , Fosfatos/farmacologia , Piridoxal/farmacologia , Transaminases/química , Transaminases/metabolismoRESUMO
BACKGROUND AND PURPOSE: Dorsal root ganglion MR imaging (MR gangliography) is increasingly gaining clinical-scientific relevance. However, dorsal root ganglion morphometry by MR imaging is typically performed under the assumption of ellipsoid geometry, which remains to be validated. MATERIALS AND METHODS: Sixty-four healthy volunteers (37 [57.8%] men; mean age, 31.5 [SD, 8.3] years) underwent MR gangliography of the bilateral L4-S2 levels (3D-T2WI TSE spectral attenuated inversion recovery-sampling perfection with application-optimized contrasts by using different flip angle evolution, isotropic voxels = 1.1 mm³, TE = 301 ms). Ground truth dorsal root ganglion volumes were bilaterally determined for 96 dorsal root ganglia (derivation cohort) by expert manual 3D segmentation by 3 independent raters. These ground truth dorsal root ganglion volumes were then compared with geometric ellipsoid dorsal root ganglion approximations as commonly practiced for dorsal root ganglion morphometry. On the basis of the deviations from ellipsoid geometry, improved volume estimation could be derived and was finally applied to a large human validation cohort (510 dorsal root ganglia). RESULTS: Commonly used equations of ellipsoid geometry underestimate true dorsal root ganglion volume by large degrees (factor = 0.42-0.63). Ground truth segmentation enabled substantially optimizing dorsal root ganglion geometric approximation using its principal axes lengths by deriving the dorsal root ganglion volume term of [Formula: see text]. Using this optimization, the mean volumes of 510 lumbosacral healthy dorsal root ganglia were as follows: L4: 211.3 (SD, 52.5) mm³, L5: 290.7 (SD, 90.9) mm³, S1: 384.2 (SD, 145.0) mm³, and S2: 192.4 (SD, 52.6) mm³. Dorsal root ganglion volume increased from L4 to S1 and decreased from S1 to S2 (P < .001). Dorsal root ganglion volume correlated with subject height (r = . 22, P < .001) and was higher in men (P < .001). CONCLUSIONS: Dorsal root ganglion volumetry by measuring its principal geometric axes on MR gangliography can be substantially optimized. By means of this optimization, dorsal root ganglion volume distribution was estimated in a large healthy cohort for the clinically most relevant lumbosacral levels, L4-S2.
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Gânglios Espinais , Imageamento por Ressonância Magnética , Adulto , Feminino , Gânglios Espinais/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , MasculinoRESUMO
OBJECTIVE: We assessed the association between methamphetamine use and lack of viral suppression among a cohort of HIV-seropositive persons who inject drugs (PWID) in Hai Phong, Vietnam. DESIGN: Cohort study with random effects logit modeling and mediation analysis for antiretroviral therapy (ART) adherence. METHODS: PWID were recruited from October 2016 to October 2017; HIV-seropositive PWID were enrolled in a cohort to assess HIV viral loads, changes in drug use, risk behaviors, and ART adherence during 24-month follow-up. Methamphetamine use in last 30 days was divided into three categories: 0 days (no use), 1-19 days (intermediate), and 20 or more days (heavy). Bivariate and a multivariable random effects logit models were used to assess the relationship between methamphetamine use and not being virally suppressed. We also assessed self-reported ART adherence as a mediating factor. RESULTS: A total of 645 HIV-seropositive PWID were included at baseline; 95% male, average age 40 (SDâ=â6.4). At baseline, methamphetamine use in last 30 days was 64% no use, 32% intermediate use, 4% heavy use. Approximately 74% of PWID reported high/complete adherence; 76% were at viral suppression. In random effects analysis, recent methamphetamine use was associated with not being virally suppressed during follow-up (adjusted odds ratio: 1.84, 95% confidence interval: 1.06, 3.17); the effect was not explained by a mediating effect of self-reported adherence to ART. CONCLUSION: Recent methamphetamine use is associated with not being virally suppressed among PWID. The results of this study indicate the need for targeted interventions for methamphetamine use with special focus on those with HIV infection.
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Fármacos Anti-HIV/uso terapêutico , Usuários de Drogas/psicologia , Infecções por HIV , Metanfetamina/uso terapêutico , Abuso de Substâncias por Via Intravenosa/complicações , Adulto , Terapia Antirretroviral de Alta Atividade , Estudos de Coortes , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Adesão à Medicação/estatística & dados numéricos , Metanfetamina/efeitos adversos , Pessoa de Meia-Idade , Assunção de Riscos , Abuso de Substâncias por Via Intravenosa/epidemiologia , Cooperação e Adesão ao Tratamento , Resultado do Tratamento , Vietnã/epidemiologia , Carga ViralRESUMO
Shape, tip projection, and position can be controlled by the use of septal extension grafts (SEG). A retrospective cohort study of patients undergoing primary and secondary rhinoplasty was reviewed. The purpose of this study was to analyze maintenance of nasal length, dorsal length, and nasolabial angle postoperatively comparing different types of SEG using standardized photography and digital measurement. Two-hundred twenty-one patients undergoing rhinoplasty were included. There was a statistically significant change regarding the nasolabial angle during the time of follow-up decreasing from 97.53 to 95.30 degrees. No changes could be found in dorsal and nasal length. There was no significant difference among the techniques used to fixate the SEG. The nasolabial angle appeared to decrease from the position 2 weeks postoperatively without changes in the dorsal and nasal length. This means that the decrease in the nasolabial angle depends on the swelling effect and not on drooping of the tip confirming the reliability of SEG over time.
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Septo Nasal/cirurgia , Rinoplastia , Humanos , Fotografação , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do TratamentoRESUMO
BACKGROUND: Progressive multifocal leukoencephalopathy is a demyelinating CNS disorder. Reactivation of John Cunningham virus leads to oligodendrocyte infection with lysis and consequent axonal loss due to demyelination. Patients usually present with confusion and seizures. Late diagnosis and lack of adequate therapy options persistently result in permanent impairment of brain functions. Due to profound T cell depletion, impairment of T-cell function and potent immunosuppressive factors, allogeneic hematopoietic cell transplantation recipients are at high risk for JCV reactivation. To date, PML is almost universally fatal when occurring after allo-HCT. METHODS: To optimize therapy specificity, we enriched JCV specific T-cells out of the donor T-cell repertoire from the HLA-identical, anti-JCV-antibody positive family stem cell donor by unstimulated peripheral apheresis [1]. For this, we selected T cells responsive to five JCV peptide libraries via the Cytokine Capture System technology. It enables the enrichment of JCV specific T cells via identification of stimulus-induced interferon gamma secretion. RESULTS: Despite low frequencies of responsive T cells, we succeeded in generating a product containing 20 000 JCV reactive T cells ready for patient infusion. The adoptive cell transfer was performed without complication. Consequently, the clinical course stabilized and the patient slowly went into remission of PML with JCV negative CSF and containment of PML lesion expansion. CONCLUSION: We report for the first time feasibility of generating T cells with possible anti-JCV activity from a seropositive family donor, a variation of virus specific T-cell therapies suitable for the post allo transplant setting. We also present the unusual case for successful treatment of PML after allo-HCT via virus specific T-cell therapy.
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Transplante de Células-Tronco Hematopoéticas , Vírus JC , Leucoencefalopatia Multifocal Progressiva , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Imunoterapia Adotiva , Leucoencefalopatia Multifocal Progressiva/terapia , LinfócitosRESUMO
In February 2004, anthropogenic radionuclides (137Cs, 236U, 239Pu and 240Pu), transported from the Sahara Desert, were observed in the Monaco air, and later in water and sediment samples collected at the DYFAMED site in the northwest (NW) Mediterranean Sea. While 236U and 137Cs in Saharan dust particles showed a high solubility in seawater, Pu isotopes were particle reactive in the water column and in the sediment. The impact of the Saharan deposition was found at 0-1.0 cm of the sediment core for 236U and 137Cs, and between 1.0 and 1.5 cm for Pu isotopes. The excess of 236U was observed more in the water column than in the sediment, whereas the 239+240Pu total inventories were comparable in the water column and the sediment. This single-day particle event represented 72% of annual atmospheric deposition in Monaco. At the DYFAMED site, it accounted for 10% (137Cs) and 15% (239+240Pu) activities of sinking particles during the period of the highest mass flux collected at the 200 and 1000 m water depths, and for a significant proportion of the total annual atmospheric input to the NW Mediterranean Sea (28-37% for 137Cs and 34-45% for 239+240Pu). Contributions to the total 137Cs and 239+240Pu sediment inventories were estimated to be 14% and 8%, respectively. The Saharan dust deposition phenomenon (atmospheric input, water column and sediment) offered a unique case to study origin and accumulation rates of radionuclides in the NW Mediterranean Sea.
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Monitoramento de Radiação , Água do Mar , África do Norte , Atmosfera , Poeira , Sedimentos Geológicos , Mar Mediterrâneo , Mônaco , Poluentes Radioativos da ÁguaRESUMO
Regenerative medicine aims to repair, replace, or restore function to tissues damaged by aging, disease, or injury. Partial organ resection is not only a common clinical approach in cancer therapy but also an experimental injury model used to examine mechanisms of regeneration and repair in organs. We performed a partial resection, or partial sialoadenectomy, in the female murine submandibular salivary gland (SMG) to establish a model for investigation of repair mechanisms in salivary glands (SGs). After partial sialoadenectomy, we performed whole-gland measurements over a period of 56 d and found that the gland increased slightly in size. We used microarray analysis and immunohistochemistry (IHC) to examine messenger RNA and protein changes in glands over time. Microarray analysis identified dynamic changes in the transcriptome 3 d after injury that were largely resolved by day 14. At the 3-d time point, we detected gene signatures for cell cycle regulation, inflammatory/repair response, and extracellular matrix (ECM) remodeling in the partially resected glands. Using quantitative IHC, we identified a transient proliferative response throughout the gland. Both secretory epithelial and stromal cells expressed Ki67 that was detectable at day 3 and largely resolved by day 14. IHC also revealed that while most of the gland underwent a wound-healing response that resolved by day 14, a small region of the gland showed an aberrant sustained fibrotic response characterized by increased levels of ECM deposition, sustained Ki67 levels in stromal cells, and a persistent M2 macrophage response through day 56. The partial submandibular salivary gland resection model provides an opportunity to examine a normal healing response and an aberrant fibrotic response within the same gland to uncover mechanisms that prevent wound healing and regeneration in mammals. Understanding regional differences in the wound-healing responses may ultimately affect regenerative therapies for patients.
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Glândulas Salivares , Glândula Submandibular , Animais , Matriz Extracelular , Feminino , Humanos , Macrófagos , Camundongos , Medicina Regenerativa , Glândulas Salivares/cirurgia , Glândula Submandibular/cirurgia , TranscriptomaRESUMO
AIM: To evaluate if diffusion-tensor-imaging MR-Neurography (DTI-MRN) can detect lesions of peripheral nerves due to polyneuropathy in patients with type 2 diabetes. METHODS: Ten patients with type 2 diabetes with polyneuropathy (DPN), 10 patients with type 2 diabetes without polyneuropathy (nDPN) as well as 20 healthy controls (HC) were included. DTI-MRN covered proximal (sciatic nerve) and distal regions (tibial nerve) of the lower extremity. Fractional-anisotropy (FA) and diffusivity (mean (MD), axial (AD) and radial (RD)) were calculated and compared to neuropathy severity. Conventional T2-relaxation-time and proton-spin-density data were obtained from a multi-echo SE sequence. Furthermore, we evaluated sensitivity and specificity of DTI-MRN from receiver operating characteristics (ROC). RESULTS: The proximal and distal FA was lowest in patients with DPN compared with nDPN and HC (pâ¯<â¯0.01). Likewise, proximal and distal RD was highest in patients with DPN (pâ¯<â¯0.01). MD and AD were also significantly different though less pronounced. ROC curve analyses of DTI separated nDPN and DPN with area-under-the-curve values ranging from 0.65 to 0.98. T2-relaxation-time and proton-spin-density could not differentiate between nDPN and DPN. CONCLUSION: DTI-MRN accurately detects DPN by lower nerve FA and higher RD. These alterations are likely to reflect both proximal and distal nerve fiber pathology in patients with type 2 diabetes.
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Diabetes Mellitus Tipo 2/complicações , Neuropatias Diabéticas/diagnóstico por imagem , Imagem de Tensor de Difusão , Polineuropatias/diagnóstico por imagem , Idoso , Neuropatias Diabéticas/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polineuropatias/etiologia , Nervo Isquiático/diagnóstico por imagem , Nervo Isquiático/fisiopatologia , Nervo Tibial/diagnóstico por imagem , Nervo Tibial/fisiopatologiaRESUMO
Basidiomata were found on dead stems of wild native Formosa palm (Arenga engleri) in Taiwan. The fungus was identified based on morphology and internal transcribed spacer sequence comparison as the oil palm pathogen Marasmius palmivorus. A pathogenicity test with cultivated mycelium of M. palmivorus positively produced disease symptoms and death of non-wounded Formosa palm tree seedlings under excessive moisture conditions. These results indicate that mycelial inoculum may be more important for pathogenesis than spore inoculum and that the fungus does not require wounds for entry into the plant. Host records in the literature are critically revised. The extended geographical and host distribution indicate a greater risk by M. palmivorus in palm plantations than hitherto anticipated. SIGNIFICANCE AND IMPACT OF THE STUDY: Certain palm species are susceptible to disease caused by Marasmius palmivorus, particularly in oil and coconut palm plantations in tropical countries. Hitherto, there is no published information on the morphology and pathogenicity of the species in Taiwan.
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Arecaceae/microbiologia , Marasmius/patogenicidade , Doenças das Plantas/microbiologia , Arecaceae/classificação , Óleo de Palmeira , Plântula/microbiologia , Taiwan , ÁrvoresRESUMO
BACKGROUND AND PURPOSE: In addition to the 4 histopathologically defined entities of medulloblastoma, 4 distinct genetically defined subgroups have been included in the World Health Organization classification of 2016. The smallest subgroup is the medulloblastoma with activated wingless pathway. The goal of this study was to identify a typical MR imaging morphology in a larger number of pediatric patients with wingless pathway medulloblastoma. MATERIALS AND METHODS: From January 2001 to October 2017, of 75 patients with histologically confirmed and molecularly subgrouped wingless pathway medulloblastomas recruited to the German Pediatric Brain Tumor (HIT) trials, 38 patients (median age, 12.8 ± 4.6 years at diagnosis; 24 [63.2%] female) had preoperative imaging that passed the entry criteria for this study. Images were rated by the local standardized imaging criteria of the National Reference Center of Neuroradiology. Additionally, a modified laterality score was used to determine tumor localization and extension. RESULTS: Twenty-eight of 38 (73.7%) were primary midline tumors but with a lateral tendency in 39.3%. One extensively eccentric midline tumor was rated by the laterality score as in an off-midline position. Five tumors were found in the cerebellopontine angle; 3, in the deep white matter; and 2, in a cerebellar hemisphere. Leptomeningeal dissemination was rare (11.5%). In 60.5%, intratumoral blood-degradation products were found, and 26.3% showed cysts with blood contents. CONCLUSIONS: According to our observations, wingless pathway medulloblastomas are not preferentially off-midline tumors as postulated in previous studies with smaller wingless pathway medulloblastoma cohorts. Dense intratumoral blood-degradation products and cysts with blood contents are frequently found and might help to differentiate wingless pathway medulloblastoma from other medulloblastoma subtypes.
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Neoplasias Cerebelares/diagnóstico por imagem , Neoplasias Cerebelares/genética , Meduloblastoma/diagnóstico por imagem , Meduloblastoma/genética , Via de Sinalização Wnt/genética , Adolescente , Neoplasias Cerebelares/patologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Meduloblastoma/patologia , Mutação , Estudos Retrospectivos , Adulto JovemRESUMO
Macrocyclic compounds are an attractive modality for drug development, but the limited availability of large, structurally diverse macrocyclic libraries hampers the discovery of leads. Here, we describe the discovery of efficient macrocyclization reactions based on thiol-to-amine ligations using bis-electrophiles, their application to synthesize and screen large libraries of macrocyclic compounds, and the identification of potent small macrocyclic ligands. The thiol-to-amine cyclization reactions showed unexpectedly high yields for a wide substrate range, which obviated product purification and enabled the generation and screening of an 8988 macrocycle library with a comparatively small effort. X-ray structure analysis of an identified thrombin inhibitor (K i = 42 ± 5 nM) revealed a snug fit with the target, validating the strategy of screening large libraries with a high skeletal diversity. The approach provides a route for screening large sub-kilodalton macrocyclic libraries and may be applied to many challenging drug targets.
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Aminas/química , Compostos Macrocíclicos/química , Bibliotecas de Moléculas Pequenas , Compostos de Sulfidrila/química , Antitrombinas/química , Antitrombinas/farmacologia , Ciclização , Descoberta de Drogas , Humanos , Ligantes , Compostos Macrocíclicos/síntese química , Compostos Macrocíclicos/farmacologia , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Inibidores da Tripsina/química , Inibidores da Tripsina/farmacologiaRESUMO
AIMS: To demonstrate the plant growth-promoting potential of a wood-decay mushroom. METHODS AND RESULTS: A wild strain of a white rot fungus (Pleurotus pulmonarius) was found to convert 10 mmol l-1 L-tryptophan (TRP) to approximately 15 µg ml-1 indole-3-acetic acid (IAA) under the optimal growth conditions of 30°C and pH 5 for 15 days. Results of gas chromatography-mass spectrometry indicated IAA synthesis through the indole-3-pyruvic acid pathway when using cellulose as a sole carbon source. The mycelium as well as the culture filtrate promoted the growth and chlorophyll content of seedlings. In a monocotyledonous plant (rice), the number of lateral roots was increased experimentally, whereas in a dicotyledonous plant (tomato), the fungus led to an increased length of shoots and roots. CONCLUSIONS: TRP-dependent IAA production was demonstrated for the first time for P. pulmonarius and may be responsible for enhancing plant growth in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: Synthesis of IAA as the most prevalent phytohormone in plants has been demonstrated for soil microfungi. Pleurotus pulmonarius is reported as an IAA-producing wood-decay macrofungus. The higher temperature optimum of P. pulmonarius isolated from subtropical environment compared to other Pleurotus species from temperate regions makes it more suitable for application in subtropical/tropical regions.
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Reguladores de Crescimento de Plantas , Raízes de Plantas , Pleurotus , Ácidos Indolacéticos/metabolismo , Solanum lycopersicum , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/microbiologia , Pleurotus/química , Pleurotus/metabolismo , Plântula/efeitos dos fármacos , Plântula/microbiologia , Triptofano/metabolismoRESUMO
This work proposes an approach for Cu2+ sensing in water which combines the selectivity of the Gly-Gly-His (GGH) peptide probe with the sensitivity of the electrolyte-gated organic field-effect transistor (EGOFET). The oligopeptide probe was immobilized onto the gate electrode of the transistor by electrooxidation of the primary amine of the glycine moiety. Cu2+ complexation by the grafted GGH was at first electrochemically evidenced, using cyclic and square wave voltammetries, then it was demonstrated that GGH-functionalized EGOFETs can transduce Cu2+ complexation through a significant threshold voltage shift and therefore a change in drain current. The limit of detection is ca. 10-12 M and the sensitivity in the linear range (10-12 - 10-8 M) is 1â¯mAâ¯dec-1 (drain current variations).
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Técnicas Biossensoriais , Cobre/isolamento & purificação , Peptídeos/química , Cobre/química , Eletrólitos/química , Limite de Detecção , Oligopeptídeos/química , Transistores Eletrônicos , Água/químicaRESUMO
In our research on biologically active compounds from Vietnamese marine invertebrates, rare melibiose-containing glycosphingolipids were found in a sample of a sponge-coral association (Desmapsamma anchorata/Carijoa riisei). Melibiosylceramides were analyzed as constituents of some multi-component RP-HPLC fractions, and the structures of 14 new (1b, 3b, 4a-4c, 6a-6c, 8b, 9a, 9b, 10b, 11a, 11b) and five known (2b, 5a-5c, 7b) natural compounds were elucidated using NMR, mass spectrometry, optical rotation, and chemical transformations. These α-d-Galp-(1â6)-ß-d-Glcp-(1 â 1)-ceramides (presumably sponge-derived compounds) were shown to contain phytosphingosine-type n-t17:0 (1), (6E)-n-t17:1 (2), i-t17:0 (3), n-t18:0 (4), (6E)-n-t18:1 (5), i-t18:0 (6), (6E)-i-t18:1 (7), i-t19:0 (8), (6E)-i-t19:1 (9), ai-t19:0 (10), and (6E)-ai-t19:1 (11) backbones N-acylated with saturated straight-chain (2R)-2-hydroxy C21 (a), C22 (b), and C23 (c) acids. Characteristic trends in the fragmentations of the terminal parts of tetraacetylated normal-chain and iso- and anteiso-branched sphingoid bases were observed using GC/MS. The total sum of melibiosylceramides and compound 5b caused a reduction in colony formation of human melanoma cells.