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1.
J Cell Biol ; 223(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38722279

RESUMO

In addition to its well-established role in actin assembly, profilin 1 (PFN1) has been shown to bind to tubulin and alter microtubule growth. However, whether PFN1's predominant control over microtubules in cells occurs through direct regulation of tubulin or indirectly through the polymerization of actin has yet to be determined. Here, we manipulated PFN1 expression, actin filament assembly, and actomyosin contractility and showed that reducing any of these parameters for extended periods of time caused an adaptive response in the microtubule cytoskeleton, with the effect being significantly more pronounced in neuronal processes. All the observed changes to microtubules were reversible if actomyosin was restored, arguing that PFN1's regulation of microtubules occurs principally through actin. Moreover, the cytoskeletal modifications resulting from PFN1 depletion in neuronal processes affected microtubule-based transport and mimicked phenotypes that are linked to neurodegenerative disease. This demonstrates how defects in actin can cause compensatory responses in other cytoskeleton components, which in turn significantly alter cellular function.


Assuntos
Actinas , Microtúbulos , Profilinas , Animais , Humanos , Camundongos , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Actinas/genética , Actomiosina/metabolismo , Microtúbulos/metabolismo , Neurônios/metabolismo , Profilinas/metabolismo , Profilinas/genética , Tubulina (Proteína)/metabolismo , Tubulina (Proteína)/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-38724202

RESUMO

The American Society of Neuroradiology has expanded its global presence, driven by the efforts of the International Collaborations Committee. This committee is actively involved in training radiologists and fostering collaborations worldwide in the fields of education, research, and community service. This article explores key initiatives of the committee, such as the Anne G. Osborn ASNR International Outreach Professor Program, the International Imaging Series, and Virtual Reading Rooms. Additionally, we provide insight into recent developments related to the pandemic and outline future opportunities.

3.
medRxiv ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38699303

RESUMO

Background: Single-cell technologies have unveiled various transcriptional states in different brain cell types. Transcription factors (TFs) regulate the expression of related gene sets, thereby controlling these diverse expression states. Apolipoprotein E (APOE), a pivotal risk-modifying gene in Alzheimer's disease (AD), is expressed in specific glial transcriptional states associated with AD. However, it is still unknown whether the upstream regulatory programs that modulate its expression are shared across brain cell types or specific to microglia and astrocytes. Methods: We used pySCENIC to construct state-specific gene regulatory networks (GRNs) for resting and activated cell states within microglia and astrocytes based on single-nucleus RNA sequencing data from AD patients' cortices from the Knight ADRC-DIAN cohort. We then identified replicating TF using data from the ROSMAP cohort. We identified sets of genes co-regulated with APOE by clustering the GRN target genes and identifying genes differentially expressed after the virtual knockout of TFs regulating APOE. We performed enrichment analyses on these gene sets and evaluated their overlap with genes found in AD GWAS loci. Results: We identified an average of 96 replicating regulators for each microglial and astrocyte cell state. Our analysis identified the CEBP, JUN, FOS, and FOXO TF families as key regulators of microglial APOE expression. The steroid/thyroid hormone receptor families, including the THR TF family, consistently regulated APOE across astrocyte states, while CEBP and JUN TF families were also involved in resting astrocytes. AD GWAS-associated genes (PGRN, FCGR3A, CTSH, ABCA1, MARCKS, CTSB, SQSTM1, TSC22D4, FCER1G, and HLA genes) are co-regulated with APOE. We also uncovered that APOE-regulating TFs were linked to circadian rhythm (BHLHE40, DBP, XBP1, CREM, SREBF1, FOXO3, and NR2F1). Conclusions: Our findings reveal a novel perspective on the transcriptional regulation of APOE in the human brain. We found a comprehensive and cell-type-specific regulatory landscape for APOE, revealing distinct and shared regulatory mechanisms across microglia and astrocytes, underscoring the complexity of APOE regulation. APOE-co-regulated genes might also affect AD risk. Furthermore, our study uncovers a potential link between circadian rhythm disruption and APOE regulation, shedding new light on the pathogenesis of AD.

5.
PLoS Biol ; 22(4): e3002607, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38687811

RESUMO

Unbiased data-driven omic approaches are revealing the molecular heterogeneity of Alzheimer disease. Here, we used machine learning approaches to integrate high-throughput transcriptomic, proteomic, metabolomic, and lipidomic profiles with clinical and neuropathological data from multiple human AD cohorts. We discovered 4 unique multimodal molecular profiles, one of them showing signs of poor cognitive function, a faster pace of disease progression, shorter survival with the disease, severe neurodegeneration and astrogliosis, and reduced levels of metabolomic profiles. We found this molecular profile to be present in multiple affected cortical regions associated with higher Braak tau scores and significant dysregulation of synapse-related genes, endocytosis, phagosome, and mTOR signaling pathways altered in AD early and late stages. AD cross-omics data integration with transcriptomic data from an SNCA mouse model revealed an overlapping signature. Furthermore, we leveraged single-nuclei RNA-seq data to identify distinct cell-types that most likely mediate molecular profiles. Lastly, we identified that the multimodal clusters uncovered cerebrospinal fluid biomarkers poised to monitor AD progression and possibly cognition. Our cross-omics analyses provide novel critical molecular insights into AD.


Assuntos
Doença de Alzheimer , Encéfalo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Humanos , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Camundongos , Transcriptoma/genética , Proteômica/métodos , Masculino , Biomarcadores/metabolismo , Metabolômica/métodos , Aprendizado de Máquina , Feminino , Progressão da Doença , Idoso , Modelos Animais de Doenças , Multiômica
6.
Support Care Cancer ; 32(4): 271, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581472

RESUMO

PURPOSE: In this work, we aimed to describe the strategy of the weekly SARS-CoV-2 RT-PCR surveillance program that was implemented in our bone marrow transplantation (BMT) unit. METHODS: Our unit performed SARS-CoV-2 RT-PCR before admission and then weekly during hospitalization even if the patient was asymptomatic. From May 2021 to May 2022, we collected data from all patients that were admitted in the BMT unit to perform transplantation. The total of SARS-CoV-2 RT-PCR performed and the positive rate were described. RESULTS: During the study period, 65 patients were admitted for HSCT. A total of 414 SARS-CoV-2 RT-PCR were performed. Two cases were detected (positivity rate, 0.48%). After the positive test, both patients were isolated outside the BMT unit. CONCLUSION: We postulate that diagnosing these patients and isolating them outside the transplantation unit may have prevented secondary symptomatic cases.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Transplante de Medula Óssea , Brasil/epidemiologia , Teste para COVID-19 , Técnicas de Laboratório Clínico , Hospitais de Ensino
7.
Vet Clin Pathol ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684480

RESUMO

BACKGROUND: The current bone marrow (BM) reference intervals (RI) are based on a limited number of cats. Age-related changes in BM variables might be important, possibly affecting the interpretation of the results. OBJECTIVES: Establish BM cytologic reference intervals (RIs) and association of age and sex on these findings, in healthy juvenile and young adult cats. METHODS: BM aspirates of cats deemed healthy based on history and clinical, CBC, serum chemistry findings, and negative retrovirus serology were obtained and examined cytologically. The examination included a 1000-nucleated differential cell count and cell morphologic assessment. RIs were calculated using parametric, robust, and nonparametric methods. The cytologic findings were examined for associations with sex and age. RESULTS: The study included 40 cats (females, 22 [55%]; males, 18 [45%]) with a median age of 1.5 years (range 0.5-5). Most calculated RIs were similar to those previously reported. BM plasma cell and monocyte counts were weakly and positively correlated with age (rs, .312 and .373, respectively; P < .05). Metarubricytes were higher in females (mean, 25.1%; SD, 6.0%) than males (mean, 21.2%; SD, 6.0%; P < .05). CONCLUSIONS: The BM differential cell counts determined in this study can serve as RIs for cats aged 0.5-5 years.

8.
J Morphol ; 285(4): e21693, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38602442

RESUMO

In insect taxa with homogeneous external morphology, genital structures often emerge as essential traits for interspecific differentiation. In the tribe Ptomaphagini (Coleoptera, Leiodidae, Cholevinae), precise identification often depends on analyzing the male genital morphology, even at the genus level. Here, we present a new character for diagnosing the genera Paulipalpina Gnaspini & Peck, 1996 and Parapaulipalpina Gnaspini, 1996. This feature, which we dub 'paralobe', is a projection arising from the internal surface of the right lobe of the aedeagal apex. Based on its absence in other beetles, including other Ptomaphagini, we recognize it as a putative synapomorphy for those genera. The recognition of this previously overlooked structure adds important information for understanding the sequence of changes that occurred in the male genitalia among the genera of Ptomaphagini.


Assuntos
Besouros , Masculino , Animais , Fenótipo
10.
J Comp Pathol ; 210: 15-24, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479335

RESUMO

Feline infectious peritonitis (FIP) is an important cause of death in cats. Thoracic manifestations are less common than abdominal manifestations, and FIP-associated respiratory disease is poorly documented. This study aimed to investigate pathological findings in the respiratory tract of cats with FIP and the occurrence and distribution of feline coronavirus antigen in the respiratory tract using immunohistochemistry. A retrospective study was carried out on 112 cats with FIP, of which 66 had inflammatory histological lesions in the respiratory tract (58.9%) and were included in this study. Three major gross patterns were defined: marked fibrin deposition in the thoracic cavity with lung atelectasis; marked fibrin deposition in the thoracic cavity with lung pyogranulomas; and lung pyogranulomas without thoracic effusion. Histological analysis revealed primary lesions in the visceral pleura and lung parenchyma at a similar frequency, with multifocal to diffuse presentations. Marked lesions were commonly observed. Five major histological patterns were defined: pleuritis; pleuritis and vasculitis/perivascular injury in the lung parenchyma; pleuritis and pneumonia; perivascular injury in the parenchyma without pleuritis; and pneumonia without pleuritis. In the pleura and pulmonary parenchyma, FIP virus antigen was detected in perivascular and peribronchial macrophages and in macrophages within bronchial-associated lymphoid tissue and foci of necrosis and inflammation in the pleura and lung parenchyma. Co-infections with retroviruses were detected in 47 cats (71.2%), mainly with feline leukemia virus (62.2%). Although FIP is a systemic disease, some cats developed significant lesions in the thoracic cavity, including involvement of the upper respiratory tract and presenting respiratory signs, without other classic signs of FIP. This work advances our knowledge of FIP in the respiratory system, helping veterinarians to recognize the various presentations of this disease.


Assuntos
Doenças do Gato , Peritonite Infecciosa Felina , Pleurisia , Pneumonia , Gatos , Animais , Estudos Retrospectivos , Sistema Respiratório/patologia , Pleurisia/veterinária , Pneumonia/veterinária , Fibrina
11.
J Org Chem ; 89(6): 4009-4018, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38441063

RESUMO

The conformational equilibria of selectively halogenated cyclohexanes are explored both experimentally (VT-NMR) for 1,1,4,-trifluorocyclohexane 7 and by computational analysis (M06-2X/aug-cc-pVTZ level), with the latter approach extending to a wider range of more highly fluorinated cyclohexanes. Perhaps unexpectedly, 7ax is preferred over the 7eq conformation by ΔG = 1.06 kcal mol-1, contradicting the accepted norm for substituents on cyclohexanes. The axial preference is stronger again in 1,1,3,3,4,5,5,-heptafluorocyclohexane 9 (ΔG = 2.73 kcal mol-1) as the CF2 groups further polarize the isolated CH2 hydrogens. Theoretical decomposition of electrostatic and hyperconjugative effects by natural bond orbital analysis indicated that nonclassical hydrogen bonding (NCHB) between the C-4 fluorine and the diaxial hydrogens at C-2 and C-6 in cyclohexane 7 and 9 largely accounts for the observed bias. The study extended to changing fluorine (F) for chlorine (Cl) and bromine (Br) at the pseudoanomeric position in the cyclohexanes. Although these halogens do not become involved in NCHBs, they polarize the geminal -CHX- hydrogen at the pseudoanomeric position to a greater extent than fluorine, and consequent electrostatic interactions influence conformer stabilities.

12.
Int J Food Microbiol ; 416: 110662, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38461734

RESUMO

Salmonella Typhimurium is a foodborne pathogen often found in the poultry production chain. Antibiotics have been used to reduce S. Typhimurium contamination in poultry aviaries and improve chicken growth. However, antibiotics were banned in several countries. Alternatively, organic acids, such as propionic acid (PA), can control pathogens. This study determined the PA minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and mathematically modeled S. Typhimurium growth/inactivation kinetics under the influence of PA at different pH values (4.5, 5.5, and 6.5) which are within the pH range of the chicken gastrointestinal tract. The PA MIC against S. Typhimurium was pH-dependent, resulting in 5.0, 3.5 and 9.0 mM undissociated PA at pH 4.5, 5.5, and 6.5, respectively. The Baranyi and Roberts and the Weibull model fit growth and inactivation data well, respectively. Secondary models were proposed. The validated model predicted 3-log reduction of S. Typhimurium in 3 h at 68.2 mM of undissociated PA and pH 4.5. The models presented a good capacity to describe the kinetics of S. Typhimurium subjected to PA, representing a useful tool to predict PA antibacterial action depending on the pH.


Assuntos
Propionatos , Salmonella typhimurium , Animais , Contagem de Colônia Microbiana , Antibacterianos/farmacologia , Concentração de Íons de Hidrogênio , Galinhas/microbiologia , Cinética
13.
Biometals ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38538957

RESUMO

Over recent years, we have been living under a pandemic, caused by the rapid spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). One of the major virulence factors of Coronaviruses is the Non-structural protein 1 (Nsp1), known to suppress the host cells protein translation machinery, allowing the virus to produce its own proteins, propagate and invade new cells. To unveil the molecular mechanisms of SARS-CoV2 Nsp1, we have addressed its biochemical and biophysical properties in the presence of calcium, magnesium and manganese. Our findings indicate that the protein in solution is a monomer and binds to both manganese and calcium, with high affinity. Surprisingly, our results show that SARS-CoV2 Nsp1 alone displays metal-dependent endonucleolytic activity towards both RNA and DNA, regardless of the presence of host ribosome. These results show Nsp1 as new nuclease within the coronavirus family. Furthermore, the Nsp1 double variant R124A/K125A presents no nuclease activity for RNA, although it retains activity for DNA, suggesting distinct binding sites for DNA and RNA. Thus, we present for the first time, evidence that the activities of Nsp1 are modulated by the presence of different metals, which are proposed to play an important role during viral infection. This research contributes significantly to our understanding of the mechanisms of action of Coronaviruses.

14.
Indian J Microbiol ; 64(1): 225-228, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38468738

RESUMO

Mannosylerythritol-lipids-B (MEL-B) are microbial-produced glycolipids with skincare properties, notably moisturizing, antimelanogenic, antimicrobial, and antiaging. Thus, there is a potential use of MEL-B in a formulation for treating acne-prone skin. This study investigated the antimicrobial effect of MEL-B against the Gram-positive bacteria Cutibacterium acnes. The broth macro dilution method was used to evaluate the growth of C. acnes (3-4 CFU/mL), in the absence (positive control) or presence of MEL-B (128, 192, 256, and 512 µg/mL). Additionally, the leakage of genetic materials was used to determine the potential drug-induced membrane disruption of glycolipids. The amount of DNA and RNA release was quantified spectrophotometrically at 260 nm. Macro dilution technique and membrane integrity experiments showed that MEL-B does not have antimicrobial activity against C. acnes. Indeed, MEL-B assisted C. acnes growth. Ultimately, MEL-B has been reported as a remarkably active compound for skincare formulations; however, preliminarily, it should be avoided for acneic skin.

15.
Drug Chem Toxicol ; : 1-5, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38465510

RESUMO

It has been reported that glyphosate, one of the most common herbicides used in agriculture, impairs locomotion and cognition. Glyphosate has a variable half-life in soil up to biotic and/or abiotic factors transform the molecule in metabolites such as the aminomethylphosphonic acid (AMPA) that has a longer half-life. In this study, female Sprague Dawley rats were acutely exposed to different doses of glyphosate or AMPA (i.e. 10, 56 or 100 mg/kg) and, subsequently, the acetylcholinesterase (AChE) activity was measured in the hippocampus, prefrontal cortex (PFC) and the gastrocnemius muscle. Both glyphosate and AMPA produced a similar decrease in the AChE activity in all the tissues tested. These results suggest that interference with normal cholinergic neurotransmission may be one of the mechanisms involved in glyphosate-induced motor alterations in rats. Moreover, our results highlight the biological importance of AMPA as a molecule with anticholinesterase action in brain and skeletal muscle. To our knowledge, this is the first report showing in vivo that AMPA, the major metabolite of glyphosate, behaves as an organophosphate.

16.
Diabetes Res Clin Pract ; 209: 111593, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38403174

RESUMO

Obesity is a prevalent problem in people living with T1D (PwT1D), and it has been linked to cardiovascular disease in this population. The use of low dose weekly Semaglutide (0,5 mg) was evaluated in a cohort of PwT1D and excess weight.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Humanos , Hipoglicemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Aumento de Peso , Receptor do Peptídeo Semelhante ao Glucagon 1
17.
Mol Phylogenet Evol ; 194: 108025, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38342160

RESUMO

Labrundinia is a highly recognizable lineage in the Pentaneurini tribe (Diptera, Chironomidae). The distinct predatory free-swimming larvae of this genus are typically present in unpolluted aquatic environments, such as small streams, ponds, lakes, and bays. They can be found on the bottom mud, clinging to rocks and wood, and dwelling among aquatic vegetation. Labrundinia has been extensively studied in ecological research and comprises 39 species, all but one of which has been described from regions outside the Palearctic. Earlier phylogenetic studies have suggested that the initial diversification of the genus likely occurred in the Neotropical Region, with its current presence in the Nearctic Region and southern South America being the result of subsequent dispersal events. Through the integration of molecular and morphological data in a calibrated phylogeny, we reveal a complex and nuanced evolutionary history for Labrundinia, providing insights into its biogeographical and diversification patterns. In this comprehensive study, we analyze a dataset containing 46 Labrundinia species, totaling 10,662 characters, consisting of 10,616 nucleotide sites and 46 morphological characters. The molecular data was generated mainly by anchored enrichment hybrid methods. Using this comprehensive dataset, we inferred the phylogeny of the group based on a total evidence matrix. Subsequently, we employed the generated tree for time calibration and further analysis of biogeography and diversification patterns. Our findings reveal multiple dispersal events out of the Neotropics, where the group originated in the late Cretaceous approximately 72 million years ago (69-78 Ma). We further reveal that the genus experienced an early burst of diversification rates during the Paleocene, which gradually decelerated towards the present-day. We also find that the Neotropics have played a pivotal role in the evolution of Labrundinia by serving as both a cradle and a museum. By "cradle," we mean that the region has been a hotspot for the origin and diversification of new Labrundinia lineages, while "museum" refers to the region's ability to preserve ancestral lineages over extended periods. In summary, our findings indicate that the Neotropics have been a key source of genetic diversity for Labrundinia, resulting in the development of distinctive adaptations and characteristics within the genus. This evidence highlights the crucial role that these regions have played in shaping the evolutionary trajectory of Labrundinia.


Assuntos
Chironomidae , Animais , Filogenia , Filogeografia , América do Sul , Larva
18.
Environ Toxicol Pharmacol ; 106: 104381, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311300

RESUMO

In recent decades, glyphosate and glyphosate-based herbicides (GBH) have been extensively used in agriculture all over the world. Initially, they were considered safe, but rising evidence suggests that these molecules reach the central nervous system producing metabolic, functional, and permanent alterations that impact cognition and behavior. This theoretical and non-systematic review involved searching, integrating, and analyzing preclinical evidence regarding the effects of acute, sub-chronic, and chronic exposure to glyphosate and GBH on cognition, behavior, neural activity, and development in adult and juvenile rodents following perinatal exposition. In addition, this review gathers the mechanisms underlying the neurotoxicity of glyphosate mediating cognitive and behavioral alterations. Furthermore, clinical evidence of the effects of exposition to GBH on human health and its possible link with several neurological disorders was revised.


Assuntos
Herbicidas , Síndromes Neurotóxicas , Adulto , Humanos , Feminino , Gravidez , Glifosato , Cognição , Síndromes Neurotóxicas/etiologia , Herbicidas/toxicidade , Agricultura
19.
Front Psychol ; 15: 1342592, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384351

RESUMO

It is important to be able to differentiate mindfulness-based programs in terms of their model, therapeutic elements, and supporting evidence. This article compares mindfulness-based cognitive therapy (MBCT), developed for relapse prevention in depression, and mindfulness-integrated cognitive behavior therapy (MiCBT), developed for transdiagnostic applications, on: (1) origins, context and theoretical rationale (why), (2) program structure, practice and, professional training (how), and (3) evidence (what). While both approaches incorporate behavior change methods, MBCT encourages behavioral activation, whereas MiCBT includes various exposure procedures to reduce avoidance, including a protocol to practice equanimity during problematic interpersonal interactions, and a compassion training to prevent relapse. MBCT has a substantial research base, including multiple systematic reviews and meta-analyses. It is an endorsed preventative treatment for depressive relapse in several clinical guidelines, but its single disorder approach might be regarded as a limitation in many health service settings. MiCBT has a promising evidence base and potential to make a valuable contribution to psychological treatment through its transdiagnostic applicability but has not yet been considered in clinical guidelines. While greater attention to later stage dissemination and implementation research is recommended for MBCT, more high quality RCTs and systematic reviews are needed to develop the evidence base for MiCBT.

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