7 research outputs found
Atrazine degradation patterns: the role of straw cover and herbicide application history
In Brazil, atrazine (ATZ) is widely applied to maize (Zea mays L.) fields for weed control. The presence of ATZ and its metabolites in soil and water matrices has become a matter of some concern for governmental authorities as well as for society at large. This study evaluated the patterns of ATZ degradation (mineralization, extractable and non-extractable ATZ residues, and metabolite formation) in a Brazilian Typic Paleudult. Soil samples from a cultivated area under a no-tillage system with a history of ATZ application were incubated with 14C-ATZ in both the presence and absence of straw cover on the soil surface, and the evolved 14CO2 was determined by liquid scintillation. Samples from an area with native vegetation, adjacent to the cultivated area, were also incubated as a control. A higher mineralization of ATZ was observed in the cultivated soil (> 85 %) in comparison with the native soil (10 %) after 85 days of incubation. In addition to the higher mineralization and hydroxyatrazine (HA) formation, a rapid decrease in the water-extractable residues was observed in the cultivated soil. When the cultivated soil was covered with straw, mineralization was reduced by up to 30 % although a small amount of remobilization to the soil occurred within the 85 days. Straw cover hindered the degradation of ATZ in cultivated soils; whereas an accelerated biodegradation was due to repeated applications of ATZ, which may have selected microbiota more skilled at biodegrading the herbicide
Randomized controlled phase 2 trial of hydroxychloroquine in childhood interstitial lung disease
Background
No results of controlled trials are available for any of the few treatments offered to children with interstitial lung diseases (chILD). We evaluated hydroxychloroquine (HCQ) in a phase 2, prospective, multicentre, 1:1-randomized, double-blind, placebo-controlled, parallel-group/crossover trial. HCQ (START arm) or placebo were given for 4 weeks. Then all subjects received HCQ for another 4 weeks. In the STOP arm subjects already taking HCQ were randomized to 12 weeks of HCQ or placebo (= withdrawal of HCQ). Then all subjects stopped treatment and were observed for another 12 weeks.
Results
26 subjects were included in the START arm, 9 in the STOP arm, of these four subjects participated in both arms. The primary endpoint, presence or absence of a response to treatment, assessed as oxygenation (calculated from a change in transcutaneous O 2 -saturation of ≥ 5%, respiratory rate ≥ 20% or level of respiratory support), did not differ between placebo and HCQ groups. Secondary endpoints including change of O 2 -saturation ≥ 3%, health related quality of life, pulmonary function and 6-min-walk-test distance, were not different between groups. Finally combining all placebo and all HCQ treatment periods did not identify significant treatment effects. Overall effect sizes were small. HCQ was well tolerated, adverse events were not different between placebo and HCQ.
Conclusions
Acknowledging important shortcomings of the study, including a small study population, the treatment duration, lack of outcomes like lung function testing below age of 6 years, the small effect size of HCQ treatment observed requires careful reassessments of prescriptions in everyday practice (EudraCT-Nr.: 2013-003714-40, www.clinicaltrialsregister.eu , registered 02.07.2013)
Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines
The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points
Atrazine degradation patterns: the role of straw cover and herbicide application history
In Brazil, atrazine (ATZ) is widely applied to maize (Zea mays L.) fields for weed control. The presence of ATZ and its metabolites in soil and water matrices has become a matter of some concern for governmental authorities as well as for society at large. This study evaluated the patterns of ATZ degradation (mineralization, extractable and non-extractable ATZ residues, and metabolite formation) in a Brazilian Typic Paleudult. Soil samples from a cultivated area under a no-tillage system with a history of ATZ application were incubated with 14C-ATZ in both the presence and absence of straw cover on the soil surface, and the evolved 14CO2 was determined by liquid scintillation. Samples from an area with native vegetation, adjacent to the cultivated area, were also incubated as a control. A higher mineralization of ATZ was observed in the cultivated soil (> 85 %) in comparison with the native soil (10 %) after 85 days of incubation. In addition to the higher mineralization and hydroxyatrazine (HA) formation, a rapid decrease in the water-extractable residues was observed in the cultivated soil. When the cultivated soil was covered with straw, mineralization was reduced by up to 30 % although a small amount of remobilization to the soil occurred within the 85 days. Straw cover hindered the degradation of ATZ in cultivated soils; whereas an accelerated biodegradation was due to repeated applications of ATZ, which may have selected microbiota more skilled at biodegrading the herbicide
Atrazine degradation patterns: the role of straw cover and herbicide application history
ABSTRACT: In Brazil, atrazine (ATZ) is widely applied to maize (Zea mays L.) fields for weed control. The presence of ATZ and its metabolites in soil and water matrices has become a matter of some concern for governmental authorities as well as for society at large. This study evaluated the patterns of ATZ degradation (mineralization, extractable and non-extractable ATZ residues, and metabolite formation) in a Brazilian Typic Paleudult. Soil samples from a cultivated area under a no-tillage system with a history of ATZ application were incubated with 14C-ATZ in both the presence and absence of straw cover on the soil surface, and the evolved 14CO2 was determined by liquid scintillation. Samples from an area with native vegetation, adjacent to the cultivated area, were also incubated as a control. A higher mineralization of ATZ was observed in the cultivated soil (> 85 %) in comparison with the native soil (10 %) after 85 days of incubation. In addition to the higher mineralization and hydroxyatrazine (HA) formation, a rapid decrease in the water-extractable residues was observed in the cultivated soil. When the cultivated soil was covered with straw, mineralization was reduced by up to 30 % although a small amount of remobilization to the soil occurred within the 85 days. Straw cover hindered the degradation of ATZ in cultivated soils; whereas an accelerated biodegradation was due to repeated applications of ATZ, which may have selected microbiota more skilled at biodegrading the herbicide
Minimal information for studies of extracellular vesicles 2018 (MISEV2018) : a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines
The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles ("MISEV") guidelines for the field in 2014. We now update these "MISEV2014" guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points
Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines
The last decade has seen a sharp increase in the number
of scientific publications describing physiological and
pathological functions of extracellular vesicles (EVs), a
collective term covering various subtypes of cell-released,
membranous structures, called exosomes, microvesicles,
microparticles, ectosomes, oncosomes, apoptotic bodies, and many
other names. However, specific issues arise when working with
these entities, whose size and amount often make them difficult
to obtain as relatively pure preparations, and to characterize
properly. The International Society for Extracellular Vesicles
(ISEV) proposed Minimal Information for Studies of Extracellular
Vesicles ("MISEV") guidelines for the field in 2014. We now
update these "MISEV2014" guidelines based on evolution of the
collective knowledge in the last four years. An important point
to consider is that ascribing a specific function to EVs in
general, or to subtypes of EVs, requires reporting of specific
information beyond mere description of function in a crude,
potentially contaminated, and heterogeneous preparation. For
example, claims that exosomes are endowed with exquisite and
specific activities remain difficult to support experimentally,
given our still limited knowledge of their specific molecular
machineries of biogenesis and release, as compared with other
biophysically similar EVs. The MISEV2018 guidelines include
tables and outlines of suggested protocols and steps to follow
to document specific EV-associated functional activities.
Finally, a checklist is provided with summaries of key points