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2.
Environ Sci Technol ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39049709

RESUMO

Biobased chemicals, crucial for the net-zero chemical industry, rely on lignocellulose residues as a major feedstock. However, its availability and environmental impacts vary greatly across regions. By 2050, we estimate that 3.0-5.2 Gt of these residues will be available from the global forest and agricultural sectors, with key contributions from Brazil, China, India, and the United States. This supply satisfies the growing global feedstock demands for plastics when used efficiently. Forest residues have 84% lower climate change impacts than agricultural residues on average globally but double the land-use-related biodiversity loss. Biobased plastics may reduce climate change impacts relative to fossil-based alternatives but are insufficient to fulfill net-zero targets. In addition, they pose greater challenges in terms of biodiversity loss and water stress. Avoiding feedstock sourcing from biodiversity-rich areas could halve lignocellulose residues-related biodiversity loss without significantly compromising availability. Improvements in region-specific feedstock sourcing, agricultural management and biomass utilization technologies are warranted for transitioning toward a sustainable chemical industry.

4.
Diabetologia ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38981930

RESUMO

AIMS/HYPOTHESIS: Alterations in circadian rhythms increase the likelihood of developing type 2 diabetes and CVD. Circadian rhythms are controlled by several core clock genes, which are expressed in nearly every cell, including immune cells. Immune cells are key players in the pathophysiology of type 2 diabetes, and participate in the atherosclerotic process that underlies cardiovascular risk in these patients. The role of the core clock in the leukocytes of people with type 2 diabetes and the inflammatory process associated with it are unknown. We aimed to evaluate whether the molecular clock system is impaired in the leukocytes of type 2 diabetes patients and to explore the mechanism by which this alteration leads to an increased cardiovascular risk in this population. METHODS: This is an observational cross-sectional study performed in 25 participants with type 2 diabetes and 28 healthy control participants. Clinical and biochemical parameters were obtained. Peripheral blood leukocytes were isolated using magnetic bead technology. RNA and protein lysates were obtained to assess clock-related gene transcript and protein levels using real-time PCR and western blot, respectively. Luminex XMAP technology was used to assess levels of inflammatory markers. Leukocyte-endothelial interaction assays were performed by perfusing participants' leukocytes or THP-1 cells (with/without CLK8) over a HUVEC monolayer in a parallel flow chamber using a dynamic adhesion system. RESULTS: Participants with type 2 diabetes showed increased BMAL1 and NR1D1 mRNA levels and decreased protein levels of circadian locomotor output cycles kaput (CLOCK), cryptochrome 1 (CRY1), phosphorylated basic helix-loop-helix ARNT like 1 (p-BMAL1) and period circadian protein homologue 2 (PER2). Correlation studies revealed that these alterations in clock proteins were negatively associated with glucose, HbA1c, insulin and HOMA-IR levels and leukocyte cell counts. The leukocyte rolling velocity was reduced and rolling flux and adhesion were enhanced in individuals with type 2 diabetes compared with healthy participants. Interestingly, inhibition of CLOCK/BMAL1 activity in leukocytes using the CLOCK inhibitor CLK8 mimicked the effects of type 2 diabetes on leukocyte-endothelial interactions. CONCLUSIONS/INTERPRETATION: Our study demonstrates alterations in the molecular clock system in leukocytes of individuals with type 2 diabetes, manifested in increased mRNA levels and decreased protein levels of the core clock machinery. These alterations correlated with the impaired metabolic and proinflammatory profile of the participants with type 2 diabetes. Our findings support a causal role for decreased CLOCK/BMAL1 activity in the increased level of leukocyte-endothelial interactions. Overall, our data suggest that alterations in core clock proteins accelerate the inflammatory process, which may ultimately precipitate the onset of CVD in patients with type 2 diabetes.

5.
Front Med (Lausanne) ; 11: 1425449, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38966536

RESUMO

Introduction: This study aims to describe the clinical characteristics, disease activity, and structural damage in patients with axial spondyloarthritis (axSpA) who receive chronic treatment with nonsteroideal anti-inflammatory drugs (NSAIDs) or advanced therapies in a clinical setting. Methods: Cross-sectional study on axSpA patients consecutively recruited from the outpatient clinic of a tertiary hospital. We collected data on clinical and demographic characteristics, as well as treatment patterns involving NSAIDs and advanced therapies. Structural damage was assessed using mSASSS. Results: Overall, data from 193 axSpA patients (83% ankylosing spondylitis) were gathered, with a mean disease duration of 21.4 years. Of these, 85 patients (44%) were exclusively taking NSAIDs, while 108 (56%) were receiving advanced therapies, with TNF inhibitors being the predominant choice (93 out of 108, 86.1%). Among patients using NSAIDs, 64.7% followed an on-demand dosing regimen, while only 17.6% used full doses. Disease activity was low, with a mean BASDAI of 3.1 and a mean ASDAS-CRP of 1.8. In comparison to patients under chronic NSAID treatment, those taking advanced therapies were primarily male (69.4% versus 51.8%, p = 0.025) and significantly younger (mean age of 49 versus 53.9 years, p = 0.033). Additionally, patients on advanced therapies exhibited lower ASDAS-CRP (p = 0.046), although CRP serum levels and BASDAI scores did not differ between the two groups. In the multivariable analysis, therapy (NSAID versus biological treatment) was not independently associated with ASDAS-CRP, BASDAI or mSASSS. Conclusion: This cross-sectional analysis of a real-world cohort of axSpA patients shows positive clinical and radiological outcomes for both NSAIDs and advanced therapies.

6.
Sci Adv ; 10(29): eado2623, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39018398

RESUMO

Diatoms are major players in the global carbon cycle, and their metabolism is affected by ocean conditions. Understanding the impact of changing inorganic nutrients in the oceans on diatoms is crucial, given the changes in global carbon dioxide levels. Here, we present a genome-scale metabolic model (iMK1961) for Cylindrotheca closterium, an in silico resource to understand uncharacterized metabolic functions in this ubiquitous diatom. iMK1961 represents the largest diatom metabolic model to date, comprising 1961 open reading frames and 6718 reactions. With iMK1961, we identified the metabolic response signature to cope with drastic changes in growth conditions. Comparing model predictions with Tara Oceans transcriptomics data unraveled C. closterium's metabolism in situ. Unexpectedly, the diatom only grows photoautotrophically in 21% of the sunlit ocean samples, while the majority of the samples indicate a mixotrophic (71%) or, in some cases, even a heterotrophic (8%) lifestyle in the light. Our findings highlight C. closterium's metabolic flexibility and its potential role in global carbon cycling.


Assuntos
Diatomáceas , Diatomáceas/metabolismo , Diatomáceas/genética , Diatomáceas/crescimento & desenvolvimento , Ciclo do Carbono , Oceanos e Mares , Água do Mar , Modelos Biológicos , Transcriptoma , Redes e Vias Metabólicas
7.
Org Chem Front ; 11(7): 2008-2014, 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-39007032

RESUMO

Cyclopropanes are recurrent structural motifs in natural products and bioactive molecules. Recently, biocatalytic cyclopropanations have emerged as a powerful approach to access enantioenriched cyclopropanes, complementing chemocatalytic approaches developed over the last several decades. Here, we report the development of a first biocatalytic strategy for cyclopropanation using ethyl α-diazopyruvate as a novel enzyme-compatible carbene precursor. Using myoglobin variant Mb(H64V,V68G) as the biocatalyst, this method afforded the efficient synthesis of α-cyclopropylpyruvates in high diastereomeric ratios and enantiomeric excess (up to 99% ee). The ketoester moiety in the cyclopropane products can be used to synthesize diverse optically pure cyclopropane derivatives. Furthermore, the enzymatically obtained α-cyclopropylpyruvate products could be converted into enantiopure cyclobutenoates via a metal-free photochemical ring expansion without loss of optical activity.

8.
Foods ; 13(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38998616

RESUMO

When looking for new ingredients to process red meat, poultry, and fish products, it is essential to consider using vegetable resources that can replace traditional ingredients such as animal fat and synthetic antioxidants that may harm health. The Amazon, home to hundreds of edible fruit species, can be a viable alternative for new ingredients in processing muscle food products. These fruits have gained interest for their use as natural antioxidants, fat replacers, colorants, and extenders. Some of the fruits that have been tested include açai, guarana, annatto, cocoa bean shell, sacha inchi oil, and peach palm. Studies have shown that these fruits can be used as dehydrated products or as liquid or powder extracts in doses between 250 and 500 mg/kg as antioxidants. Fat replacers can be added directly as flour or used to prepare emulsion gels, reducing up to 50% of animal fat without any detrimental effects. However, oxidation problems of the gels suggest that further investigation is needed by incorporating adequate antioxidant levels. In low doses, Amazon fruit byproducts such as colorants and extenders have been shown to have positive technological and sensory effects on muscle food products. While evidence suggests that these fruits have beneficial health effects, their in vitro and in vivo nutritional effects should be evaluated in muscle food products containing these fruits. This evaluation needs to be intended to identify safe doses, delay the formation of key oxidation compounds that directly affect health, and investigate other factors related to health.

9.
Sci Rep ; 14(1): 15662, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977836

RESUMO

Scincidae is one of the most species-rich and cosmopolitan clades of squamate reptiles. Abundant disarticulated fossil material has also been attributed to this group, however, no complete pre-Cenozoic crown-scincid specimens have been found. A specimen in Burmite (99 MYA) is the first fossil that can be unambiguously referred to this clade. Our analyses place it as nested within extant skinks, supported by the presence of compound osteoderms formed by articulated small ostedermites. The specimen has a combination of dorsal and ventral compound osteoderms and overlapping cycloid scales that is limited to skinks. We propose that this type of osteoderm evolved as a response to an increased overlap of scales, and to reduced stiffness of the dermal armour. Compound osteoderms could be a key innovation that facilitated diversification in this megadiverse family.


Assuntos
Âmbar , Fósseis , Animais , Fósseis/anatomia & histologia , Lagartos/anatomia & histologia , Filogenia , Evolução Biológica
10.
Cryst Growth Des ; 24(13): 5775-5780, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38983119

RESUMO

We report herein, by means of structural and computational analyses, a comprehensive study of the capability of differently substituted haloalkenes to behave as electron density acceptors in noncovalent interactions. The nature of these interactions between haloalkenes and Lewis bases highly depends on the number and nature of the halogen atoms bound to the carbon-carbon double bond. When hydrogen bonds, which generally dominate for mono- and dihaloalkenes, cannot be formed, we observe the establishment of attractive interactions in which an sp2 carbon atom, belonging to an acyclic C=C double bond, plays the role of the Lewis acid via its π* antibonding orbital.

11.
Artigo em Inglês | MEDLINE | ID: mdl-39018667

RESUMO

BACKGROUND: Noise generation and anterior knee pain can occur after primary total knee arthroplasty (TKA) and may affect patient satisfaction. Polyethylene design in cruciate-sacrificing implants could be a variable influencing these complications. The purpose of this study was to analyze the effect of polyethylene design on noise generation and anterior knee pain. METHODS: We prospectively reviewed a cohort of patients who underwent primary TKA between 2014 and 2022 by a single surgeon using either a posterior-stabilized (PS) or ultracongruent (UC) polyethylene of the same implant design. The primary outcomes were measured through a noise generation questionnaire and the Knee Injury and Osteoarthritis Outcome Score-Patellofemoral score. RESULTS: A total of 409 TKA procedures were included, 153 (37.4%) PS and 256 (62.6%) UC. No difference was noted in the Knee Injury and Osteoarthritis Outcome Score-Patellofemoral score between PS and UC designs (71.7 ± 26 versus 74.2 ± 23.2, P = 0.313). A higher percentage of patients in the PS cohort reported hearing (32.7% versus 22.3%, P = 0.020) or feeling noise (28.8 versus 20.3, P = 0.051) coming from their implant. No notable difference was observed in noise-related satisfaction rates. Independent risk factors of noise generation were age (OR, 0.96; P = 0.006) and PS polyethylene (OR, 1.61; P = 0.043). Noise generation was associated with decreased patient-reported outcome measure scores (P < 0.001). CONCLUSION: While there was no difference in anterior knee pain between PS and UC polyethylene designs, PS inserts exhibit higher rates of noise generation compared with UC. Noise generation had comparable satisfaction but was associated with decreased patient-reported outcome measure scores.

12.
Front Genet ; 15: 1422938, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39027885

RESUMO

Purpose: Coal mining is a vital sector in Colombia, contributing significantly to the nation's economy and the development of its regions. However, despite its importance, it has led to a gradual decline in the health of mine workers and nearby residents. While the adverse health effects of open-pit coal mining on exposed individuals have been well-documented in Colombia and globally, studies investigating genetic damage in underground coal miners are lacking. Methods: The aim of our study was to evaluate chromosomal and genotoxic damage, in peripheral blood samples from a group of underground coal miners and residents of areas exposed to coal, in the town of Samacá, Boyacá-Colombia, and in a group of unexposed individuals by using banding and molecular cytogenetic techniques, as well as cytokinesis block micronucleus assays. Results: Our results suggest that occupational exposure to coal induces chromosomal and genotoxic damage in somatic cells of underground coal miners. Chromosomal and genotoxic damage is an important step in carcinogenesis and the development of many other diseases. Our findings provide valuable insights into the effects of coal dust exposure on chromosomal integrity and genetic stability. Conclusion: Our pilot study suggests that occupational exposure to coal induces chromosomal damage in underground coal miners, highlighting the importance of validating these findings with a larger sample size. Our results highlight the need to implement prevention and protection measures, as well as educational programs for underground coal miners. Characterizing and estimating exposure risks are extremely important for the safety of people exposed occupationally and environmentally to coal and its derivatives.

13.
J Bone Joint Surg Am ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052763

RESUMO

BACKGROUND: The use of antibiotic-loaded bone cement (ALBC) to help reduce the risk of infection after primary total knee arthroplasty (TKA) is controversial. There is a paucity of in vivo data on the elution characteristics of ALBC. We aimed to determine whether the antibiotic concentrations of 2 commercially available ALBCs met the minimum inhibitory concentration (MIC) and minimum biofilm eradication concentration (MBEC) for common infecting organisms. METHODS: Forty-five patients undergoing TKA were randomized to receive 1 of the following: bone cement without antibiotic (the negative control; n = 5), a commercially available formulation containing 1 g of tobramycin (n = 20), or a commercially available formulation containing 0.5 g of gentamicin (n = 20). Intra-articular drains were placed, and fluid was collected at 4 and 24 hours postoperatively. An automated immunoassay measuring antibiotic concentration was performed, and the results were compared against published MIC and MBEC thresholds. RESULTS: The ALBC treatment groups were predominantly of White (65%) or Black (32.5%) race and were 57.5% female and 42.4% male. The mean age (and standard deviation) was 72.6 ± 7.2 years in the gentamicin group and 67.6 ± 7.4 years in the tobramycin group. The mean antibiotic concentration in the tobramycin group was 55.1 ± 37.7 µg/mL at 4 hours and 19.5 ± 13.0 µg/mL at 24 hours, and the mean concentration in the gentamicin group was 38.4 ± 25.4 µg/mL at 4 hours and 17.7 ± 15.4 µg/mL at 24 hours. Time and antibiotic concentration had a negative linear correlation coefficient (r = -0.501). Most of the reference MIC levels were reached at 4 hours. However, at 24 hours, a considerable percentage of patients had concentrations below the MIC for many common pathogens, including Staphylococcus epidermidis (gentamicin: 65% to 100% of patients; tobramycin: 50% to 85%), methicillin-sensitive Staphylococcus aureus (gentamicin: 5% to 90%; tobramycin: 5% to 50%), methicillin-resistant S. aureus (gentamicin: 5% to 65%; tobramycin: 50%), Streptococcus species (gentamicin: 10% to 100%), and Cutibacterium acnes (gentamicin: 10% to 65%; tobramycin: 100%). The aforementioned ranges reflect variation in the MIC among different strains of each organism. Gentamicin concentrations reached MBEC threshold values at 4 hours only for the least virulent strains of S. aureus and Escherichia coli. Tobramycin concentrations did not reach the MBEC threshold for any of the bacteria at either time point. CONCLUSIONS: The elution of antibiotics from commercially available ALBC decreased rapidly following TKA, and only at 4 hours postoperatively did the mean antibiotic concentrations exceed the MIC for most of the pathogens. Use of commercially available ALBC may not provide substantial antimicrobial coverage following TKA. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

14.
Cureus ; 16(6): e61839, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38975489

RESUMO

Appendicitis, characterized by inflammation and obstruction of the appendiceal lumen, is a common surgical emergency often attributed to various factors. We present the case of an 18-year-old female who developed retrocecal appendicitis following blunt abdominal trauma, a rare occurrence with significant diagnostic challenges. Initial symptoms mimicked upper abdominal trauma, evolving to classic signs of appendicitis within hours. Despite a negative pre-trauma history of abdominal pain, clinical evaluation led to a suspicion of appendicitis. Contrast-enhanced CT scan confirmed the thickening of the cecal appendix, prompting urgent surgical intervention. An open appendectomy revealed a congested retrocecal appendix, supporting the diagnosis. Our case underscores the importance of considering trauma as a potential trigger for appendicitis, especially in the absence of typical pre-trauma symptoms. Diagnostic criteria for post-trauma appendicitis are evolving, and we underscore a comprehensive clinical assessment alongside imaging modalities. While surgical management remains standard, newer approaches like endoscopic retrograde appendicitis therapy warrant exploration. Further research is essential to refine diagnostic and therapeutic strategies for this uncommon presentation, ensuring timely intervention and improved patient outcomes.

15.
Anat Rec (Hoboken) ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965784

RESUMO

The rough teiid or water cork lizard (Echinosaura horrida) is a small reptile from Colombia and Ecuador placed in a genus that contains eight species and well-known phylogenetic relationships. Here we provide a detailed description and illustrations, bone by bone, of its skull, while we discussed its intraspecific variation by comparing high-resolution computed tomography data from two specimens and the variation within the genus by including previously published data from Echinosaura fischerorum. This allowed to propose putative diagnostic character states for Echinosaura horrida and synapomorphies for Echinosaura. In addition, our discussion includes broader comparisons of new character transformations of the jugal, vomer, orbitosphenoid, and hyoid. These characters are important for diagnosing clades at different levels of the Gymnophthalmoidea phylogeny.

16.
JAMA Netw Open ; 7(6): e2414122, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38857050

RESUMO

Importance: Neurological manifestations during acute SARS-CoV-2-related multisystem inflammatory syndrome in children (MIS-C) are common in hospitalized patients younger than 18 years and may increase risk of new neurocognitive or functional morbidity. Objective: To assess the association of severe neurological manifestations during a SARS-CoV-2-related hospital admission with new neurocognitive or functional morbidities at discharge. Design, Setting, and Participants: This prospective cohort study from 46 centers in 10 countries included patients younger than 18 years who were hospitalized for acute SARS-CoV-2 or MIS-C between January 2, 2020, and July 31, 2021. Exposure: Severe neurological manifestations, which included acute encephalopathy, seizures or status epilepticus, meningitis or encephalitis, sympathetic storming or dysautonomia, cardiac arrest, coma, delirium, and stroke. Main Outcomes and Measures: The primary outcome was new neurocognitive (based on the Pediatric Cerebral Performance Category scale) and/or functional (based on the Functional Status Scale) morbidity at hospital discharge. Multivariable logistic regression analyses were performed to examine the association of severe neurological manifestations with new morbidity in each SARS-CoV-2-related condition. Results: Overall, 3568 patients younger than 18 years (median age, 8 years [IQR, 1-14 years]; 54.3% male) were included in this study. Most (2980 [83.5%]) had acute SARS-CoV-2; the remainder (588 [16.5%]) had MIS-C. Among the patients with acute SARS-CoV-2, 536 (18.0%) had a severe neurological manifestation during hospitalization, as did 146 patients with MIS-C (24.8%). Among survivors with acute SARS-CoV-2, those with severe neurological manifestations were more likely to have new neurocognitive or functional morbidity at hospital discharge compared with those without severe neurological manifestations (27.7% [n = 142] vs 14.6% [n = 356]; P < .001). For survivors with MIS-C, 28.0% (n = 39) with severe neurological manifestations had new neurocognitive and/or functional morbidity at hospital discharge compared with 15.5% (n = 68) of those without severe neurological manifestations (P = .002). When adjusting for risk factors in those with severe neurological manifestations, both patients with acute SARS-CoV-2 (odds ratio, 1.85 [95% CI, 1.27-2.70]; P = .001) and those with MIS-C (odds ratio, 2.18 [95% CI, 1.22-3.89]; P = .009) had higher odds of having new neurocognitive and/or functional morbidity at hospital discharge. Conclusions and Relevance: The results of this study suggest that children and adolescents with acute SARS-CoV-2 or MIS-C and severe neurological manifestations may be at high risk for long-term impairment and may benefit from screening and early intervention to assist recovery.


Assuntos
COVID-19 , Hospitalização , Doenças do Sistema Nervoso , SARS-CoV-2 , Síndrome de Resposta Inflamatória Sistêmica , Humanos , COVID-19/complicações , COVID-19/epidemiologia , Criança , Feminino , Masculino , Pré-Escolar , Hospitalização/estatística & dados numéricos , Adolescente , Estudos Prospectivos , Síndrome de Resposta Inflamatória Sistêmica/epidemiologia , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/epidemiologia , Lactente , Índice de Gravidade de Doença
17.
Artigo em Inglês | MEDLINE | ID: mdl-38833728

RESUMO

INTRODUCTION: Although two-stage exchange has been the standard of care for periprosthetic joint infection (PJI) in the United States, single-stage exchange is emerging as an option in select patients. The purpose of this study was to compare outcomes of patients undergoing single-stage and two-stage exchange using strict surgical indications. METHODS: We reviewed a consecutive series of 196 patients with diagnosed PJI undergoing revision total knee and hip arthroplasty from 2017 to 2021. Patients were excluded if they had PJI history, plastic surgery coverage, or extensive bone loss requiring endoprosthesis. We compared the number of patients PJI-free at 1-year follow-up using MusculoSkeletal Infection Society criteria and patients requiring re-revision between the single-stage and two-stage groups. RESULTS: In total, 126 patients met inclusion criteria. Of 61 knee patients (48.4%), 22 underwent single-stage (36%) and 39 underwent two-stage (63.9%). Of 65 hip patients (51.6%), 38 underwent single-stage (58.5%) and 27 underwent two-stage (41.5%). At a mean follow-up of 1.95 ± 0.88 years, a higher rate of knee patients were classified as having treatment success in the single-stage group (77.3% versus 69.2%, P = 0.501), however with comparable septic failure rates (18.1% single-stage versus 17.9% two-stage; P = 0.982). At a mean follow-up of 1.81 ± 0.9 years, a higher rate of hip patients were classified as having treatment success in the single-stage group (94.7% versus 81.5%, P = 0.089), and more patients had septic failures in the two-stage group (18.5% versus 5.3%; P = 0.089). No differences were observed in the microorganism profile. More total complications (P = 0.021) and mortalities were found in the single-stage knee cohort than in the two-stage cohort (22.7% versus 2.6%; P = 0.011). CONCLUSION: Single-stage arthroplasty is a viable alternative to standard two-stage exchange in patients with PJI without a history of infection and with no bone or soft-tissue compromise. Additional studies with longer term follow-up are needed to evaluate its efficacy.

18.
Sci Rep ; 14(1): 13077, 2024 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844827

RESUMO

Conflicts between rural people and the Endangered Black-and-chestnut Eagle (Spizaetus isidori) are a prominent conservation concern in the northern Andes, as at least 60 eagles were poached between 2000 and 2022 in response to poultry predation. Here, we conducted direct observations to analyze the Black-and-chestnut Eagle diet and evaluated how forest cover affects the feeding habits of the species during nestling-rearing periods in 16 nests located in different human-transformed Andean landscapes of Ecuador and Colombia. We analyzed 853 prey items (46 species) delivered to nestlings. We used Generalized Linear Models to test whether the percent forest cover calculated within varying buffer distances around each nest and linear distances from the nest to the nearest settlement and pasture areas were predictors of diet diversity and biomass contribution of prey. Forest cover was not a factor that affected the consumption of poultry; however, the eagle regularly preyed on chickens (Gallus gallus) (i.e., domestic Galliformes) which were consumed by 15 of the 16 eagle pairs, with biomass contributions (14.57% ± 10.55) representing 0.6-37% of the total prey consumed. The Black-and-chestnut Eagle is an adaptable generalist able to switch from mammalian carnivores to guans (i.e., wild Galliformes) in human-dominated landscapes, and eagles nesting in sites with low forest cover had a less diverse diet than those in areas with more intact forests. Management actions for the conservation of this avian top predator require studies on the eagle's diet in areas where human persecution is suspected or documented, but also maintaining forest cover for the wild prey of the species, development of socio-economic and psychological assessments on the drivers behind human-eagle conflicts, and the strengthening of technical capacities of rural communities, such as appropriate poultry management.


Assuntos
Dieta , Águias , Espécies em Perigo de Extinção , Comportamento Predatório , Animais , Comportamento Predatório/fisiologia , Águias/fisiologia , Humanos , Equador , Colômbia , Animais Selvagens , Florestas , Conservação dos Recursos Naturais , Galinhas/fisiologia , Comportamento Alimentar
19.
BMC Ecol Evol ; 24(1): 77, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38872101

RESUMO

BACKGROUND: Unenlagiine paravians are among the most relevant Gondwanan theropod dinosaur clades for understanding the origin of birds, yet their fossil record remains incomplete, with most taxa being represented by fragmentary material and/or separated by lengthy temporal gaps, frustrating attempts to characterize unenlagiine evolution. RESULTS AND CONCLUSIONS: Here we describe Diuqin lechiguanae gen. et sp. nov., a new unenlagiine taxon from the Upper Cretaceous (Santonian) Bajo de la Carpa Formation of the Neuquén Basin of Neuquén Province in northern Patagonia, Argentina that fills a substantial stratigraphic gap in the fossil record of these theropods. Although known only from a very incomplete postcranial skeleton, the preserved bones of Diuqin differ from corresponding elements in other unenlagiines, justifying the erection of the new taxon. Moreover, in several morphological aspects, the humerus of Diuqin appears intermediate between those of geologically older unenlagiines from the Neuquén Basin (e.g., Unenlagia spp. from the Turonian-Coniacian Portezuelo Formation) and that of the stratigraphically younger, larger-bodied Austroraptor cabazai from the Campanian-Maastrichtian Allen Formation. Consequently, the morphology of the new taxon appears to indicate a transitional stage in unenlagiine evolution. Phylogenetic analysis recovers Diuqin as a paravian with multiple plausible systematic positions, but the strongest affinity is with Unenlagiinae. The humerus of the new form exhibits subcircular punctures near its distal end that are interpreted as feeding traces most likely left by a conical-toothed crocodyliform, mammal, or theropod, the latter potentially corresponding to a megaraptorid or another unenlagiine individual. Thus, in addition to filling important morphological and temporal gaps in unenlagiine evolutionary history, the new taxon also offers information relating to the paleoecology of these theropods.


Assuntos
Dinossauros , Fósseis , Argentina , Animais , Dinossauros/anatomia & histologia , Dinossauros/classificação , Filogenia , Evolução Biológica
20.
Molecules ; 29(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38930828

RESUMO

The development of new compounds to treat Chagas disease is imperative due to the adverse effects of current drugs and their low efficacy in the chronic phase. This study aims to investigate nitroisoxazole derivatives that produce oxidative stress while modifying the compounds' lipophilicity, affecting their ability to fight trypanosomes. The results indicate that these compounds are more effective against the epimastigote form of T. cruzi, with a 52 ± 4% trypanocidal effect for compound 9. However, they are less effective against the trypomastigote form, with a 15 ± 3% trypanocidal effect. Additionally, compound 11 interacts with a higher number of amino acid residues within the active site of the enzyme cruzipain. Furthermore, it was also found that the presence of a nitro group allows for the generation of free radicals; likewise, the large size of the compound enables increased interaction with aminoacidic residues in the active site of cruzipain, contributing to trypanocidal activity. This activity depends on the size and lipophilicity of the compounds. The study recommends exploring new compounds based on the nitroisoxazole skeleton, with larger substituents and lipophilicity to enhance their trypanocidal activity.


Assuntos
Isoxazóis , Tripanossomicidas , Trypanosoma cruzi , Trypanosoma cruzi/efeitos dos fármacos , Tripanossomicidas/farmacologia , Tripanossomicidas/química , Tripanossomicidas/síntese química , Isoxazóis/química , Isoxazóis/farmacologia , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/química , Proteínas de Protozoários/antagonistas & inibidores , Relação Estrutura-Atividade , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Cisteína Endopeptidases/química , Cisteína Endopeptidases/metabolismo , Animais , Domínio Catalítico , Estrutura Molecular
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