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1.
Comp Biochem Physiol C Toxicol Pharmacol ; 283: 109960, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38885749

ABSTRACT

Pesticides used in rice cultivation can cause negative health effects to non-target organisms representative of natural biodiversity. In this context, the present study aimed to investigate the occurrence of pesticides in surface waters from a river that flows in the middle of a rice farming-dominated area. We were also interested in evaluate biochemical and histological effects caused by exposure (16 d) to the lower and higher concentrations of the main found herbicide (bentazone, BTZ), insecticide (chlorantraniliprole, CTP) and fungicide (tebuconazole, TBZ), isolated or mixed, in Boana faber tadpoles. No significant differences were observed in the development of the animals. Tadpoles exposed to the herbicide BTZ showed higher hepatic levels of malondialdehyde (MDA). In animals exposed to CTP, MDA levels were lower than controls. Animals exposed to the fungicide TBZ showed higher hepatic activity of glutathione S-transferase and carboxylesterase (CbE), as well as higher levels of carbonyl proteins and MDA. Animals exposed to Mix showed higher activity in CbE and glucose-6-phosphate dehydrogenase activity in the liver, as well as higher levels of MDA. In the brain and muscle of tadpoles exposed to Mix, acetylcholinesterase activity was higher. Histological changes were also observed in pesticide-exposed animals, such as increased occurrence of melanomacrophages, inflammatory infiltrates and congestion. Our data evidences the contamination of natural aquatic environments by rice pesticides, and the adverse effects of main ones in B. faber tadpoles, which suggests the contribution of pesticides derived from rice cultivation to the degradation of local biodiversity health.

2.
Gene ; 927: 148722, 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38914244

ABSTRACT

Products from stingless bees are rich reservoirs of microbial diversity, including yeasts with fermentative potential. Previously, two Saccharomyces cerevisiae strains, JP14 and IP9, were isolated from Jataí (Tetragonisca angustula) and Iraí (Nannotrigona testaceicornis) bees, respectively, aiming at mead production. Both strains presented great osmotic and sulfite tolerance, and ethanol production, although they have a high free amino nitrogen demand. Herein, their genomes were sequenced, assembled, and annotated, and the variants were compared to the S. cerevisiae S288c reference strain. The final assembly of IP9 and JP14 presented high N50 and BUSCO scores, and more than 6430 protein-coding genes. Additionally, nQuire predicted the ploidy of IP9 as diploid, but the results were not enough to determine the ploidy of JP14. The mitochondrial genomes of IP9 and JP14 presented the same gene content as S288c but the genes were rearranged and fragmented in different patterns. Meanwhile, the genes with mutations of high impact (e.g., indels, gain of stop codon) for both yeasts were enriched for transmembrane transport, electron transfer, oxidoreductase, heme binding, fructose, mannose, and glucose transport, activities related to the respiratory chain and sugar metabolism. The IP9 strain presented copy number gains in genes related to sugar transport and cell morphogenesis; in JP14, genes were enriched for disaccharide metabolism and transport, response to reactive oxygen species, and polyamine transport. On the other hand, IP9 presented copy number losses related to disaccharide, thiamine, and aldehyde metabolism, while JP14 presented depletions related to disaccharide, oligosaccharide, asparagine, and aspartate metabolism. Notably, both strains presented a killer toxin gene, annotated from the assembling of unmapped reads, representing a potential mechanism for the control of other microorganisms population in the environment. Therefore, the annotated genomes of JP14 and IP9 presented a high selective pressure for sugar and nitrogen metabolism and stress response, consistent with their isolation source and fermentative properties.

3.
Aquat Toxicol ; 273: 106978, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38870676

ABSTRACT

Pesticides are released into the environment daily, and their effects on nontarget species in aquatic ecosystems have been widely reported. To evaluate the adverse effects caused in adults of Danio rerio species exposed to the pesticides abamectin, difenoconazole, and their commercial formulations (Kraft 36EC® and Score 250EC®), both isolated and in mixtures, biochemical biomarkers were analyzed in the gills of organisms exposed to sublethal concentrations. To this end, the activities of the enzymes 7-ethoxyresorufin-O-deethylase (EROD), glucuronosyltransferase (UDPGT), glutathione-S-transferase (GST), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), lipid hydroperoxide (LH), and malondialdehyde (MDA), which are indicative of oxidative stress, were measured after 48 h of exposure to the different pesticide treatments. The results showed a significant increase in EROD activity and MDA levels in the gills of fish exposed to the commercial formulation of abamectin. When the fish were exposed to difenoconazole and its commercial formulation, an increase in GST, GPx, and MDA levels and a decrease in GR activity were observed in the gills. Furthermore, the responses of the biomarkers were more pronounced in organisms exposed to mixtures of both active ingredients and commercial formulations. It is concluded that the commercial formulations Kraft 36EC® and Score 250EC® and their mixtures cause significant alterations in the detoxification metabolism of exposed organisms and induce oxidative stress in fish.

4.
J Neurointerv Surg ; 2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38453461

ABSTRACT

BACKGROUND: Limited research exists regarding the impact of neuroimaging on endovascular thrombectomy (EVT) decisions for late-window cases of large vessel occlusion (LVO) stroke. OBJECTIVE: T0 assess whether perfusion CT imaging: (1) alters the proportion of recommendations for EVT, and (2) enhances the reliability of EVT decision-making compared with non-contrast CT and CT angiography. METHODS: We conducted a survey using 30 patients drawn from an institutional database of 3144 acute stroke cases. These were presented to 29 Canadian physicians with and without perfusion imaging. We used non-overlapping 95% confidence intervals and difference in agreement classification as criteria to suggest a difference between the Gwet AC1 statistics (κG). RESULTS: The percentage of EVT recommendations differed by 1.1% with or without perfusion imaging. Individual decisions changed in 21.4% of cases (11.3% against EVT and 10.1% in favor). Inter-rater agreement (κG) among the 29 raters was similar between non-perfusion and perfusion CT neuroimaging (κG=0.487; 95% CI 0.327 to 0.647 and κG=0.552; 95% CI 0.430 to 0.675). The 95% CIs overlapped with moderate agreement in both. Intra-rater agreement exhibited overlapping 95% CIs for all 28 raters. κG was either substantial or excellent (0.81-1) for 71.4% (20/28) of raters in both groups. CONCLUSIONS: Despite the minimal difference in overall EVT recommendations with either neuroimaging protocol one in five decisions changed with perfusion imaging. Regarding agreement we found that the use of automated CT perfusion images does not significantly impact the reliability of EVT decisions for patients with late-window LVO.

5.
J Insect Sci ; 24(2)2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38442352

ABSTRACT

The shift to a pollen diet and the evolution of more highly organized societies, i.e., eusocial, were key milestones in bee diversification over their evolutionary history, culminating in a high dependence on feeding broods with a large variety of floral resources. Here, we hypothesized that obligatory eusocial bees have a wider diet diversity than their relatives with solitary lifestyles, and this would be related to colony size. To test both hypotheses, we surveyed diet breadth data (palynological analysis) based on the Shannon-Wiener index (H') for 85 bee taxa. We also obtained colony size for 47 eusocial bee species. These data were examined using phylogenetic comparative methods. The results support the generalist strategy as a derived trait for the bee taxa evaluated here. The dietary diversity of eusocial bees (H': 2.1, on average) was 67.5% higher than that of noneusocial bees (H': 1.21, on average). There was, however, no relationship between diet breadth and colony size, indicating that smaller colonies can harvest a pollen variety as diverse as larger colonies. Taken together, these results provide new insights into the impact of lifestyle on the diversity of collected pollen. Furthermore, this work sheds light on an advantage of living in more highly structured societies irrespective of the size of the colony.


Subject(s)
Diet , Pollen , Bees , Animals , Phylogeny , Phenotype
6.
Zootaxa ; 5404(1): 5-13, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38480410

ABSTRACT

Fernando A. Silveira had the unique combination of being a sagacious scientist and a remarkable human being. Throughout his career, he made significant contributions to understanding bee diversity and keenly spread this scientific information to the academic community at large and beyond the university walls. His rich character, warm heart, strong voice and laughter are missed by those privileged to be Fernandos students, friends, mentors, and family. In this volume, we honor Fernando A. Silveira, who prematurely passed away at the age of 62, leaving three sons, his wife, and numerous friends.


Subject(s)
Holometabola , Male , Humans , Bees , Animals , Universities
7.
Zootaxa ; 5404(1): 236-257, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38480399

ABSTRACT

The genus Actenosigynes includes two species, A. fulvoniger (Michener, 1989) and A. mantiqueirensis Silveira, 2009, both oligolectic on flowers of Blumenbachia (Loasaceae) in southern Brazil. We describe a third species, Actenosigynes silveirai Siriani-Oliveira, sp. n., and provide additional evidence to the suspected narrow host-plant specificity between bees of this genus and Loasaceae. This new species was only recorded to collect resources on flowers of Aosa, a genus closely related to Blumenbachia in the subfamily Loasoideae. We illustrate female and male specimens of the three species to offer a complete summary of the morphological variation within this modestly sized genus of Neopasiphaeinae, including photographs of male genitalia and associated metasomal sterna. Moreover, we provide an identification key for the three species of Actenosigynes and the first phylogenetic and dating estimate for these taxa. The genus diversified in southern South America during the Miocene-Pliocene, following a more ancient divergence associated with the orogenic events that separated its sister-genus, Torocolletes, west of the Andes. We dedicate this newly described species to Fernando A. Silveira for his contributions to research on Brazilian bee taxonomy and biology.


Subject(s)
Hymenoptera , Magnoliopsida , Male , Bees , Animals , Phylogeny , Flowers
8.
Zootaxa ; 5404(1): 3-4, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38480411
9.
Sci Total Environ ; 925: 171679, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38494031

ABSTRACT

Coastal environments, such as those in the Santa Catarina State (SC, Brazil), are considered the primary receptors of anthropogenic pollutants. In this study, our objective was to evaluate the levels of emerging contaminants (ECs) and persistent organic pollutants (POPs) in indigenous Crassostrea gasar oysters from different regions of SC coast in the summer season (March 2022). Field collections were conducted in the São Francisco do Sul, Itajaí, Florianópolis and Laguna coastal zones. We analyzed the bioaccumulation levels of 75 compounds, including antibiotics (AB), endocrine disruptors (ED), non-steroidal anti-inflammatory drugs (NSAIDs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and pesticides. Furthermore, we assessed biomarker responses related to biotransformation, antioxidant defense, heat shock protection and oxidative damage in oysters' gills. Prevalence of ECs was observed in the central and southern regions, while the highest concentrations of POPs were detected in the central-northern regions of SC. Oysters exhibited an induction in biotransformation systems (cyp2au1 and cyp356a1, sult and GST activity) and antioxidant enzymes activities (SOD, CAT and GPx). Higher susceptibility to lipid peroxidation was observed in the animals from Florianópolis compared to other regions. Correlation analyses indicated possible associations between contaminants and environmental variables in the biomarker responses, serving as a warning related to climate change. Our results highlight the influence of anthropogenic activities on SC, serving as baseline of ECs and POPs levels in the coastal areas of Santa Catarina, indicating more critical zones for extensive monitoring, aiming to conserve coastal regions.


Subject(s)
Crassostrea , Polycyclic Aromatic Hydrocarbons , Water Pollutants, Chemical , Animals , Crassostrea/physiology , Brazil , Antioxidants/analysis , Biomarkers/metabolism , Polycyclic Aromatic Hydrocarbons/analysis , Water Pollutants, Chemical/analysis , Environmental Monitoring/methods
10.
Radiology ; 310(2): e232030, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38411520

ABSTRACT

According to the World Health Organization, climate change is the single biggest health threat facing humanity. The global health care system, including medical imaging, must manage the health effects of climate change while at the same time addressing the large amount of greenhouse gas (GHG) emissions generated in the delivery of care. Data centers and computational efforts are increasingly large contributors to GHG emissions in radiology. This is due to the explosive increase in big data and artificial intelligence (AI) applications that have resulted in large energy requirements for developing and deploying AI models. However, AI also has the potential to improve environmental sustainability in medical imaging. For example, use of AI can shorten MRI scan times with accelerated acquisition times, improve the scheduling efficiency of scanners, and optimize the use of decision-support tools to reduce low-value imaging. The purpose of this Radiology in Focus article is to discuss this duality at the intersection of environmental sustainability and AI in radiology. Further discussed are strategies and opportunities to decrease AI-related emissions and to leverage AI to improve sustainability in radiology, with a focus on health equity. Co-benefits of these strategies are explored, including lower cost and improved patient outcomes. Finally, knowledge gaps and areas for future research are highlighted.


Subject(s)
Artificial Intelligence , Radiology , Humans , Radiography , Big Data , Climate Change
11.
Aquat Toxicol ; 268: 106869, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38387247

ABSTRACT

Synthetic glucocorticoids are often found in surface waters and can cause harmful effects to aquatic organisms such as amphibians. In this work we evaluated the effects of the drugs prednisone (PD) and prednisolone (PL) on developmental, molecular, blood, biochemical and histological markers. Aquarana catesbeianus tadpoles were exposed for 16 days to environmentally relevant concentrations of 0, 0.1, 1 and 10 µg/L of both drugs. PD increased the transcript levels of the enzyme deiodinase III (Dio3), the hormones cortisol and T4 and delayed development. Changes in the thyroid gland occurred after tadpoles were exposed to both drugs, with a reduction in the diameter and number of follicles and an increase/or decrease in area. Also, both drugs caused a decrease in lymphocytes (L) and an increase in neutrophils (N), thrombocytes, the N:L ratio and lobed and notched erythrocytes. Increased activity of the enzymes superoxide dismutase, glutathione S-transferase and glucose 6-phosphate dehydrogenase was observed after exposure to PD. Furthermore, both drugs caused an increase in the activity of the enzymes catalase and glutathione peroxidase. However, only PD caused oxidative stress in exposed tadpoles, evidenced by increased levels of malondialdehyde and carbonyl proteins. Both drugs caused an increase in inflammatory infiltrates, blood cells and melanomacrophages in the liver. Our results indicate that PD was more toxic than PL, affecting development and causing oxidative stress.


Subject(s)
Prednisolone , Water Pollutants, Chemical , Animals , Larva , Prednisone/metabolism , Prednisone/pharmacology , Prednisolone/toxicity , Prednisolone/metabolism , Water Pollutants, Chemical/toxicity , Oxidative Stress
12.
Mar Environ Res ; 194: 106309, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38169221

ABSTRACT

This study aimed to carry out a general diagnosis of the contamination of the coastal marine environment of the Santa Catarina state (SC, Brazil) by different classes of environmental pollutants, as well as to evaluate possible adverse effects of the contaminants on biochemical biomarkers of oysters, Crassostrea gasar and Crassostrea rhizophorae. 107 chemicals were evaluated in water, sediment and oyster samples from nine sites along the coastline of SC. We also examined various biochemical biomarkers in the oysters' gills and digestive glands to assess potential effects of contaminants. In general, the northern and central regions of the littoral of SC presented higher occurrences and magnitudes of contaminants than the southern region, which is probably related to higher urbanization of center and northern areas of the littoral. The biomarker analysis in the oysters reflected these contamination patterns, with more significant alterations observed in regions with higher levels of pollutants. Our results may serve as a first baseline for future and more extensive monitoring actions and follow-up of the degree of contamination in the state, allowing for inspection actions and management of areas most affected by marine pollutants.


Subject(s)
Crassostrea , Environmental Pollutants , Water Pollutants, Chemical , Animals , Brazil , Biomarkers , Gills , Water Pollutants, Chemical/analysis , Environmental Monitoring/methods
13.
PLoS One ; 19(1): e0294127, 2024.
Article in English | MEDLINE | ID: mdl-38166040

ABSTRACT

BACKGROUND: Guidelines recommend the treatment of emergent large vessel ischemic stroke (ELVIS) patients presenting beyond 6 hours of last known well time with endovascular thrombectomy (EVT) based on perfusion computed tomography (CT) neuroimaging. We compared the outcomes (long-term good clinical outcomes, symptomatic intracranial hemorrhage (sICH), and mortality) of ELVIS patients according to the type of CT neuroimaging they underwent. METHODS: We searched the following databases: Medline, Embase, CENTRAL, and Scopus from January 1, 2015, to June 14, 2023. We included studies of late-presenting ELVIS patients undergoing EVT that had with data for non-perfusion and perfusion CT neuroimaging. We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Data were pooled using a random effects model. RESULTS: We found 7 observational cohorts. Non-perfusion versus perfusion CT was not statistically significantly different for both long-term clinical (n = 3,224; RR: 0.96; 95% CI 0.86 to 1.06; I2 = 18%) and sICH (n = 3,724; RR: 1.08 95% CI 0.60 to 1.94; I2 = 76%). Perfusion CT had less mortality (n = 3874; RR: 1.22; 95% CI 1.07 to 1.40; I2 = 0%). The certainty of these findings is very low because of limitations in the risk of bias, indirectness, and imprecision domains of the Grading of Recommendations, Assessment, Development and Evaluations. CONCLUSION: The use of either non-perfusion or perfusion CT neuroimaging may have little to no effect on long-term clinical outcomes and sICH for late-presenting EVT patients. Perfusion CT neuroimaging may be associated with a reduced the risk of mortality. Evidence uncertainty warrants randomized trial data.


Subject(s)
Brain Ischemia , Endovascular Procedures , Ischemic Stroke , Humans , Brain Ischemia/diagnostic imaging , Brain Ischemia/therapy , Brain Ischemia/etiology , Endovascular Procedures/methods , Intracranial Hemorrhages/etiology , Ischemic Stroke/diagnostic imaging , Ischemic Stroke/etiology , Ischemic Stroke/therapy , Perfusion , Thrombectomy/methods , Tomography, X-Ray Computed/methods , Treatment Outcome
14.
Mol Pharm ; 21(1): 38-52, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37646561

ABSTRACT

The cisplatin encapsulation into carbon nanohorns (CNH) is a promising nanoformulation to circumvent the drug dissipation and to specifically accumulate it in tumor sites. Herein, biased molecular dynamics simulations were used to analyze the transmembrane transport of the CNH loaded with cisplatin through a breast cancer cell membrane prototype. The simulations revealed a four-stage mechanism: approach, insertion, permeation, and internalization. Despite the lowest structural disturbance of the membrane provided by the nanocarrier, the average free energy barrier for the translocation was 55.2 kcal mol-1, suggesting that the passive process is kinetically unfavorable. In contrast, the free energy profiles revealed potential wells of -6.8 kcal mol-1 along the insertion stage in the polar heads region of the membrane, which might enhance the retention of the drug in tumor sites; therefore, the most likely cisplatin delivery mechanism should involve the adsorption and retention of CNH on the surface of cancer cells, allowing the loaded cisplatin be slowly released and passively transported through the cell membrane.


Subject(s)
Breast Neoplasms , Cisplatin , Humans , Female , Cisplatin/chemistry , Carbon , Breast Neoplasms/drug therapy , Biological Transport , Cell Membrane
15.
Environ Pollut ; 341: 122900, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-37952920

ABSTRACT

Tebuconazole (TBZ) and azoxystrobin (AZX) are fungicides frequently used in rice cultivation. Despite protecting crops against fungal diseases, these compounds can contaminate the natural environments close to the crops, exerting negative effects on non-target organisms, the present study aimed to characterize the contamination by fungicides of a river that flows in an area dominated by rice cultivation in the north of the state of Santa Catarina, SC, Brazil. Concentrations of TBZ and AZX found in the field were used to evaluate their negative effects on development, biochemical biomarkers and histopatology of the liver of a native tadpole species, the hammerfrog (Boana faber). Tadpoles were exposed for 16 days to the lowest (1.20 µg/L) and highest (2.60 µg/L) concentration of TBZ, lowest (0.70 µg/L) and highest (1.60 µg/L) concentration of AZX, and the mix of both fungicides at lowest and highest concentration of each found in field analyses. Exposure to the lower TBZ concentration and both concentrations of the Mix accelerated the development of tadpoles. AZX caused an increase in the activities of glutathione S-transferase (GST), carboxylesterase (CbE) and glucose-6-phosphate dehydrogenase (G6PDH) in the liver, an increase in the levels of protein carbonyls (PC) in the liver and an increase in the activity of acetylcholinesterase (AChE) in muscle of tadpoles. TBZ, on the other hand, generated an increase in GST, G6PDH, PC and histopathological severity scores in liver and in muscle AChE activity. The effects were more intense in the groups exposed to the Mix of contaminants. No treatment altered brain AChE. The data showed that the fungicides from in rice cultivation found in natural aquatic environments around the crops pose risks to the health of the animals, compromising their metabolism and development.


Subject(s)
Fungicides, Industrial , Oryza , Water Pollutants, Chemical , Animals , Fungicides, Industrial/toxicity , Acetylcholinesterase , Crops, Agricultural , Glutathione Transferase , Water Pollutants, Chemical/toxicity , Larva
16.
Plants (Basel) ; 12(19)2023 Sep 22.
Article in English | MEDLINE | ID: mdl-37836087

ABSTRACT

Competition is an important biological filter that can define crucial features of species' natural history, like survival and reproduction success. We evaluated in the Brazilian tropical savanna whether two sympatric and congenereric species, Qualea multiflora Mart. and Q. parviflora Mart. (Vochysiaceae), compete for pollinator services, testing whether there is a better competitor or whether plants present any anti-competitive mechanism. Additionally, we investigated the breeding system, pollinators, and flowering phenology of both species. The results showed that Q. multiflora and Q. parviflora are dependent on pollinators for fruit formation, as they exhibited a self-incompatible and non-agamospermic breeding system. These plants shared the same guild of pollinators, which was formed by bees and hummingbirds, and an overlap in the flower visitation time was observed. Each plant species had different pollinator attraction strategies: Q. multiflora invested in floral resource quality, while Q. parviflora invested in resource quantity. The blooming time showed a temporal flowering partition, with highly sequential flowering and no overlap. Qualea parviflora bloomed intensely from September to October, while Q. multiflora bloomed from November to January, with the flowering peak occurring in December. The two Qualea species have morphologically similar flowers, are sympatric, and share the same pollinator community, with overlapping foraging activity during the day. However, they do not compete for pollinator services as they exhibit an anti-competitive mechanism mediated by temporal flowering partition.

17.
Mar Pollut Bull ; 195: 115559, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37738876

ABSTRACT

This study aimed to assess the combined effect of hypoxia and exposure to diesel on biochemical parameters of Perna perna mussels. Mussels previously kept for 48 h in clean seawater were submitted to hypoxia for 24 h followed by reoxygenation in clean seawater for 48 h. The same procedure was done but using seawater containing 0.01 mL/L of diesel, before and after hypoxia. Antioxidant enzymes as well as levels of glutathione and lipid peroxidation were measured in gills and digestive glands. The neutral red retention time assay was also evaluated in hemocytes. Results showed that cycles of air exposure and reoxygenation caused oxidative stress and antioxidant modulation in both the gills and digestive glands. The presence of diesel in water triggered additional modulation of antioxidants under hypoxia and reoxygenation stress, apparently enhancing the capacity of mussels to avoid lipid peroxidation.

18.
J Chem Inf Model ; 63(19): 6141-6155, 2023 Oct 09.
Article in English | MEDLINE | ID: mdl-37751589

ABSTRACT

Breast cancer is one of the most frequent modalities of cancer worldwide, with notable mortality. The medication based on platinum drugs (cisplatin (cddp), carboplatin (cpx), and oxaliplatin (oxa)) is a conventional chemotherapy despite severe side effects and the development of drug resistance. In order to provide a deeper molecular description of the influx and efflux processes of platinum drugs through breast cancer tissues, this study focuses on molecular dynamics (MD) simulations of the passive translocation process through a realistic plasma membrane prototype of human breast cancer cell (c_memb). The results showed that the permeation events were mainly mediated by neutral lipids (DOPC, DOPE, and cholesterol), producing a low and temporary membrane deformation. The drug insertion in the region of polar heads was the most favorable stage of the translocation mechanism, especially for cddp and oxa with potential wells of -8.6 and -9.8 kcal mol-1, respectively. However, the potentials of mean force (PMF) revealed unfavorable kinetics for the permeation of these drugs through lipid tails, with energy barriers of 28.3 (cddp), 32.2 (cpx), and 30.4 kcal mol-1 (oxa). The low permeability coefficients (P) of cpx and oxa, which were 3 and 1 orders of magnitude inferior than for cddp, resulted from the high energy barriers for their traslocation processes through the membrane. The obtained results provide a more accurate picture of the permeation of Pt(II)-based drugs through breast cancer cells, which may be relevant for the design and evaluation of new platinum complexes.

19.
Curr Biol ; 33(16): 3409-3422.e6, 2023 08 21.
Article in English | MEDLINE | ID: mdl-37506702

ABSTRACT

Bees are the most significant pollinators of flowering plants. This partnership began ca. 120 million years ago, but the uncertainty of how and when bees spread across the planet has greatly obscured investigations of this key mutualism. We present a novel analysis of bee biogeography using extensive new genomic and fossil data to demonstrate that bees originated in Western Gondwana (Africa and South America). Bees likely originated in the Early Cretaceous, shortly before the breakup of Western Gondwana, and the early evolution of any major bee lineage is associated with either the South American or African land masses. Subsequently, bees colonized northern continents via a complex history of vicariance and dispersal. The notable early absences from large landmasses, particularly in Australia and India, have important implications for understanding the assembly of local floras and diverse modes of pollination. How bees spread around the world from their hypothesized Southern Hemisphere origin parallels the histories of numerous flowering plant clades, providing an essential step to studying the evolution of angiosperm pollination syndromes in space and time.


Subject(s)
Fossils , Magnoliopsida , Bees/genetics , Animals , Phylogeny , Genomics , Magnoliopsida/genetics , South America
20.
Environ Monit Assess ; 195(6): 784, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37261565

ABSTRACT

Land cover changes threaten biodiversity and alter the geographic distribution of forests worldwide. Studies on this topic are important to establish conservation strategies and public policies. However, different studies may propose different spatial representations due to differences when identifying, classifying, and/or mapping the same vegetation formation, as observed for the Cocais Forest region. This palm-dominated ecosystem predominates the Brazilian mid-north region in an ecotone region with 3 of the 6 Brazilian biomes. In this study, we conducted a literature review of studies that delineated and mapped the Cocais Forest, aiming to compare different mapped regions and to establish a new distribution map integrating these spatial data. We found seven sources that revealed spatial divergences in identifying the spatial distribution of Cocais Forest, including its characteristics in terms of size and shape, which could affect the conservation, socioeconomic, and cultural policies and studies carried out on this emblematic vegetation formation and influence area. The delineation proposed by de Sousa Nascimento and Lima (Revista de Políticas Públicas 189-192, 2016) encompassed the largest area. In addition, there was a lack of consensus regarding the nomenclature for this ecosystem, and few works offered a detailed description of the mapping process. Despite the different spatial distributions found for the Cocais Forest, we succeeded in establishing a common area by overlapping individual maps, resulting in the identification of a core region exclusive located in the State of Maranhão.


Subject(s)
Conservation of Natural Resources , Ecosystem , Environmental Monitoring , Forests , Biodiversity , Trees
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