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1.
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
2.
Nature ; 593(7858): 255-260, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33911285

RESUMO

Alzheimer's disease (AD) is the most prevalent cause of dementia1. Although there is no effective treatment for AD, passive immunotherapy with monoclonal antibodies against amyloid beta (Aß) is a promising therapeutic strategy2,3. Meningeal lymphatic drainage has an important role in the accumulation of Aß in the brain4, but it is not known whether modulation of meningeal lymphatic function can influence the outcome of immunotherapy in AD. Here we show that ablation of meningeal lymphatic vessels in 5xFAD mice (a mouse model of amyloid deposition that expresses five mutations found in familial AD) worsened the outcome of mice treated with anti-Aß passive immunotherapy by exacerbating the deposition of Aß, microgliosis, neurovascular dysfunction, and behavioural deficits. By contrast, therapeutic delivery of vascular endothelial growth factor C improved clearance of Aß by monoclonal antibodies. Notably, there was a substantial overlap between the gene signature of microglia from 5xFAD mice with impaired meningeal lymphatic function and the transcriptional profile of activated microglia from the brains of individuals with AD. Overall, our data demonstrate that impaired meningeal lymphatic drainage exacerbates the microglial inflammatory response in AD and that enhancement of meningeal lymphatic function combined with immunotherapies could lead to better clinical outcomes.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/imunologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Imunoterapia , Vasos Linfáticos/imunologia , Meninges/imunologia , Microglia/imunologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/imunologia , Doença de Alzheimer/genética , Doença de Alzheimer/imunologia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/efeitos dos fármacos , Animais , Anticorpos Monoclonais Humanizados/imunologia , Encéfalo/irrigação sanguínea , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Modelos Animais de Doenças , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/imunologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Masculino , Meninges/irrigação sanguínea , Meninges/citologia , Camundongos , Microglia/citologia , Microglia/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Fator C de Crescimento do Endotélio Vascular/metabolismo , Fator C de Crescimento do Endotélio Vascular/farmacologia
3.
Nature ; 571(7763): 58-62, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31270484

RESUMO

Over the course of evolution, organism size has diversified markedly. Changes in size are thought to have occurred because of developmental, morphological and/or ecological pressures. To perform phylogenetic tests of the potential effects of these pressures, here we generated a dataset of more than ten thousand descriptions of insect eggs, and combined these with genetic and life-history datasets. We show that, across eight orders of magnitude of variation in egg volume, the relationship between size and shape itself evolves, such that previously predicted global patterns of scaling do not adequately explain the diversity in egg shapes. We show that egg size is not correlated with developmental rate and that, for many insects, egg size is not correlated with adult body size. Instead, we find that the evolution of parasitoidism and aquatic oviposition help to explain the diversification in the size and shape of insect eggs. Our study suggests that where eggs are laid, rather than universal allometric constants, underlies the evolution of insect egg size and shape.


Assuntos
Ecologia , Insetos , Animais , Ovos , Feminino , Oviposição , Filogenia
4.
Crit Care Med ; 52(1): 102-111, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855674

RESUMO

OBJECTIVES: To assess whether delirium during ICU stay is associated with subsequent change in treatment of cancer after discharge. DESIGN: Retrospective cohort study. SETTING: A 50-bed ICU in a dedicated cancer center. PATIENTS: Patients greater than or equal to 18 years old with a previous proposal of cancer treatment (chemotherapy, target therapy, hormone therapy, immunotherapy, radiotherapy, oncologic surgery, and bone marrow transplantation). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We considered delirium present if Confusion Assessment Method for the ICU was positive. We assessed the association between delirium and modification of the treatment after discharge. We also performed a mediation analysis to assess both the direct and indirect (i.e., mediated by the development of functional dependence after discharge) of delirium on modification of cancer treatment and whether the modification of cancer treatment was associated with mortality at 1 year. We included 1,134 patients, of whom, 189 (16.7%) had delirium. Delirium was associated with the change in cancer treatment (adjusted odds ratio [OR], 3.80; 95% CI, 2.72-5.35). The association between delirium in ICU and change of treatment was both direct and mediated by the development of functional dependence after discharge. The proportion of the total effect of delirium on change of treatment mediated by the development of functional dependence after discharge was 33.0% (95% CI, 21.7-46.0%). Change in treatment was associated with increased mortality at 1 year (adjusted OR, 2.68; 95% CI, 2.01-3.60). CONCLUSIONS: Patients who had delirium during ICU stay had a higher rate of modification of cancer treatment after discharge. The effect of delirium on change in cancer treatment was only partially mediated by the development of functional dependence after discharge. Change in cancer treatment was associated with increased 1-year mortality.


Assuntos
Delírio , Neoplasias , Humanos , Estudos Retrospectivos , Estado Terminal/terapia , Análise de Mediação , Unidades de Terapia Intensiva , Delírio/epidemiologia , Delírio/etiologia , Estudos Prospectivos , Neoplasias/complicações , Neoplasias/terapia
5.
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
6.
Syst Biol ; 72(3): 662-680, 2023 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-36773019

RESUMO

Logical character dependency is a major conceptual and methodological problem in phylogenetic inference of morphological data sets, as it violates the assumption of character independence that is common to all phylogenetic methods. It is more frequently observed in higher-level phylogenies or in data sets characterizing major evolutionary transitions, as these represent parts of the tree of life where (primary) anatomical characters either originate or disappear entirely. As a result, secondary traits related to these primary characters become "inapplicable" across all sampled taxa in which that character is absent. Various solutions have been explored over the last three decades to handle character dependency, such as alternative character coding schemes and, more recently, new algorithmic implementations. However, the accuracy of the proposed solutions, or the impact of character dependency across distinct optimality criteria, has never been directly tested using standard performance measures. Here, we utilize simple and complex simulated morphological data sets analyzed under different maximum parsimony optimization procedures and Bayesian inference to test the accuracy of various coding and algorithmic solutions to character dependency. This is complemented by empirical analyses using a recoded data set on palaeognathid birds. We find that in small, simulated data sets, absent coding performs better than other popular coding strategies available (contingent and multistate), whereas in more complex simulations (larger data sets controlled for different tree structure and character distribution models) contingent coding is favored more frequently. Under contingent coding, a recently proposed weighting algorithm produces the most accurate results for maximum parsimony. However, Bayesian inference outperforms all parsimony-based solutions to handle character dependency due to fundamental differences in their optimization procedures-a simple alternative that has been long overlooked. Yet, we show that the more primary characters bearing secondary (dependent) traits there are in a data set, the harder it is to estimate the true phylogenetic tree, regardless of the optimality criterion, owing to a considerable expansion of the tree parameter space. [Bayesian inference, character dependency, character coding, distance metrics, morphological phylogenetics, maximum parsimony, performance, phylogenetic accuracy.].


Assuntos
Algoritmos , Filogenia , Teorema de Bayes , Fenótipo
7.
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.

8.
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.

9.
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
10.
Vet Pathol ; 61(4): 582-589, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38146917

RESUMO

Although tick infestation is a significant health problem in livestock, there are limited studies on the dermatopathological aspects of natural tick infestation in cattle. This study aimed to describe the gross and histologic aspects of cutaneous lesions caused by tick infestation in cattle. Thirteen cases were selected based on necropsy data from a 10-year retrospective study. Predispositions were observed in beef cattle (P = .049) and the Angus breed (P = .012), and lesions occurred mainly in the fall (P = .007). Gross lesions included hypotrichosis (13/13; 100%), scales (12/13; 92%), alopecia (11/13; 85%), ulcers (7/13; 54%), crusts (7/13; 54%), and erosions (2/13; 15%). These gross lesions were mainly located in the thorax (12/13; 92%), head (11/13; 85%), abdomen (10/13; 77%), neck (9/13; 69%), limbs (9/13; 69%), and perineum (9/13; 69%). Histologically, all cases had ticks adhered to the epidermis with erosions (13/13; 100%), ulcers (11/13; 85%), orthokeratotic hyperkeratosis (13/13; 100%), irregular acanthosis (13/13; 100%), intraepidermal pustules (13/13; 100%), crusts (10/13; 77%), and ballooning degeneration (4/13; 31%). In the dermis, just below the tick insertion site, there was coagulation necrosis, fibrin deposition, and inflammatory infiltrate composed of mixed cells (neutrophils, lymphocytes, plasma cells, macrophages, and few eosinophils) (9/13; 69%), neutrophils (3/13; 23%), or eosinophils (1/13; 8%). This study reinforces the different patterns of cutaneous lesions caused by tick infestation in cattle, which should be considered as a potential cause of dermatitis in this species.


Assuntos
Doenças dos Bovinos , Infestações por Carrapato , Animais , Bovinos , Doenças dos Bovinos/patologia , Doenças dos Bovinos/parasitologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/patologia , Infestações por Carrapato/parasitologia , Estudos Retrospectivos , Feminino , Masculino , Pele/patologia , Pele/parasitologia , Carrapatos , Dermatopatias/veterinária , Dermatopatias/patologia , Dermatopatias/parasitologia
11.
An Acad Bras Cienc ; 96(3): e20230078, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38865507

RESUMO

This study evaluated the effects of broiler age (A) and levels of replacement (L) of control diet (CD) on the utilization of energy and nutrients of whole corn germ. 720 one-day-old broilers (b) were allocated at completely randomized design to six treatments and six replicates, in three assays: pre-starter (1-8 days, 10 b/cage), starter (15-22 days, 6 b/cage), and grower (28-35 days, 4 b/cage) phases. The treatments were: CD and four test diets (L): 100, 150, 200, 250, or 300 g kg-1 of the CD replaced by WCG levels. The data were adjusted to the response surface model. The stationary points for apparent energy metabolizable (AME) and AME corrected for nitrogen balance (AMEn) were: 4173 and 3591 kcal kg-1, respectively, and coefficients of gross energy (AMCGE), crude protein (AMCCP), dry matter (AMCDM), and ether extract (AMCEE) were: 49.3, 40.4, 72.6, and 61.3%, respectively; and Ileal digestibility coefficient of crude protein (IDCCP), dry matter (IDCDM), digestibility crude protein values (DCP), and digestibility dry matter value (DDM) were: 78.0, 57.96, 8.50, and 56.17%, respectively. The EP for AMEn was at 18 days of age, 28 g kg-1 WCG. There was a correlation between A and L on digestibility and metabolisability of nutrient's WCG.


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Galinhas , Digestão , Metabolismo Energético , Íleo , Zea mays , Animais , Ração Animal/análise , Metabolismo Energético/fisiologia , Digestão/fisiologia , Zea mays/química , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Íleo/metabolismo , Íleo/fisiologia , Dieta/veterinária , Masculino , Distribuição Aleatória
12.
BMC Biol ; 21(1): 162, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37501205

RESUMO

BACKGROUND: Deceptive alternative mating tactics are commonly maintained at low frequencies within populations because males using them are less competitive and acquire lower fitness than those using dominant tactics. However, the successful invasion of a male deceptive tactic is plausible if deception carries no fitness cost to females. Among populations of the gift-giving spider Paratrechalea ornata, males very often offer females a deceptive worthless gift, rather than a nutritive gift. We tested the degree to which deceptive worthless gifts can occur in natural populations living under divergent environmental conditions (moderate and stressful). We examined the plasticity of morphological and behavioral traits and analyzed the fitness of females in relation to the gift type, also examining the paternity acquired by males offering either gift type. RESULTS: We demonstrated that worthless gifts can become dominant under highly stressful environmental conditions (84-100%). Individuals in such environment reach smaller sizes than those in moderate conditions. We suggest that the size reduction probably favors low metabolic demands in both sexes and may reduce the costs associated with receiving deceptive worthless gifts for females. In contrast, males living under moderate conditions varied the use of the deceptive tactic (0-95%), and worthless gifts negatively influenced female fecundity. Furthermore, male size, rather than gift content, positively impacted paternity success in the moderate but not in the stressful environment. CONCLUSIONS: Overall, this is the first empirical evidence that a reversible deceptive tactic can become dominant when the environment becomes harsh and mate choice becomes limited.


Assuntos
Comportamento Sexual Animal , Aranhas , Animais , Feminino , Masculino , Reprodução , Fenótipo
13.
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.

14.
Chem Biodivers ; : e202400667, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935347

RESUMO

Monoacylglycerols are eco-friendly and inexpensive emulsifiers with a range of applications. The traditional synthetic route is not eco-friendly, while enzymatic catalysis offers milder reaction conditions and higher selectivity. However, its application still is limited due to the costs. In this context, endophytic fungi can be source to new biocatalysts with enhanced catalytic activity. Based on this perspective, the aim of this study was perform the synthesis of MAG's through transesterification reactions of solketal and different vinyl esters, using crude and immobilized lipolytic extracts from the endophytic fungi Stemphylium lycopersici, isolated from Humiria balsamifera. The reactions were conducted using 100 mg of biocatalyst, 1 mmol of substrates, 9 : 1 n-heptane/acetone, at 40 °C, 200 rpm for 96 h. In the reactions using the ILE and stearate, laureate and decanoate vinyl esters it was possible to obtain the correspondent products with conversion rates of 52-75 %. Also, according to the structure drivers used in MCM-48 synthesis, different morphologies and conversions rates were observed. Employing [C16MI] Cl, [C14MI] Cl and [C4MI] Cl, the 1-lauroyl- glycerol conversion was 36 %, 79 % and 44 %, respectively. This is the first work involving the immobilization of an endophytic fungi and its utilization as a biocatalyst in the production of MAG's.

15.
Molecules ; 29(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38257271

RESUMO

Dye-decolorizing peroxidases (DyPs) are heme proteins with distinct structural properties and substrate specificities compared to classical peroxidases. Here, we demonstrate that DyP from the extremely radiation-resistant bacterium Deinococcus radiodurans is, like some other homologues, inactive at physiological pH. Resonance Raman (RR) spectroscopy confirms that the heme is in a six-coordinated-low-spin (6cLS) state at pH 7.5 and is thus unable to bind hydrogen peroxide. At pH 4.0, the RR spectra of the enzyme reveal the co-existence of high-spin and low-spin heme states, which corroborates catalytic activity towards H2O2 detected at lower pH. A sequence alignment with other DyPs reveals that DrDyP possesses a Methionine residue in position five in the highly conserved GXXDG motif. To analyze whether the presence of the Methionine is responsible for the lack of activity at high pH, this residue is substituted with a Glycine. UV-vis and RR spectroscopies reveal that the resulting DrDyPM190G is also in a 6cLS spin state at pH 7.5, and thus the Methionine does not affect the activity of the protein. The crystal structures of DrDyP and DrDyPM190G, determined to 2.20 and 1.53 Å resolution, respectively, nevertheless reveal interesting insights. The high-resolution structure of DrDyPM190G, obtained at pH 8.5, shows that one hydroxyl group and one water molecule are within hydrogen bonding distance to the heme and the catalytic Asparagine and Arginine. This strong ligand most likely prevents the binding of the H2O2 substrate, reinforcing questions about physiological substrates of this and other DyPs, and about the possible events that can trigger the removal of the hydroxyl group conferring catalytic activity to DrDyP.


Assuntos
Deinococcus , Extremófilos , Peróxido de Hidrogênio , Metionina , Racemetionina , Heme , Peroxidases
16.
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.

17.
Biophys J ; 122(18): 3678-3689, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37218133

RESUMO

Directed transport of cellular components is often dependent on the processive movements of cytoskeletal motors. Myosin 2 motors predominantly engage actin filaments of opposing orientation to drive contractile events and are therefore not traditionally viewed as processive. However, recent in vitro experiments with purified nonmuscle myosin 2 (NM2) demonstrated myosin 2 filaments could move processively. Here, we establish processivity as a cellular property of NM2. Processive runs in central nervous system-derived CAD cells are most apparent on bundled actin in protrusions that terminate at the leading edge. We find that processive velocities in vivo are consistent with in vitro measurements. NM2 makes these processive runs in its filamentous form against lamellipodia retrograde flow, though anterograde movement can still occur in the absence of actin dynamics. Comparing the processivity of NM2 isoforms, we find that NM2A moves slightly faster than NM2B. Finally, we demonstrate that this is not a cell-specific property, as we observe processive-like movements of NM2 in the lamella and subnuclear stress fibers of fibroblasts. Collectively, these observations further broaden NM2 functionality and the biological processes in which the already ubiquitous motor can contribute.


Assuntos
Actinas , Citoesqueleto , Actinas/fisiologia , Citoesqueleto de Actina , Proteínas do Citoesqueleto , Miosina Tipo II
18.
Hum Mol Genet ; 30(9): 811-822, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33835157

RESUMO

To identify novel risk genes and better understand the molecular pathway underlying Alzheimer's disease (AD), whole-exome sequencing was performed in 215 early-onset AD (EOAD) patients and 255 unrelated healthy controls of Han Chinese ethnicity. Subsequent validation, computational annotation and in vitro functional studies were performed to evaluate the role of candidate variants in EOAD. We identified two rare missense variants in the phosphodiesterase 11A (PDE11A) gene in individuals with EOAD. Both variants are located in evolutionarily highly conserved amino acids, are predicted to alter the protein conformation and are classified as pathogenic. Furthermore, we found significantly decreased protein levels of PDE11A in brain samples of AD patients. Expression of PDE11A variants and knockdown experiments with specific short hairpin RNA (shRNA) for PDE11A both resulted in an increase of AD-associated Tau hyperphosphorylation at multiple epitopes in vitro. PDE11A variants or PDE11A shRNA also caused increased cyclic adenosine monophosphate (cAMP) levels, protein kinase A (PKA) activation and cAMP response element-binding protein phosphorylation. In addition, pretreatment with a PKA inhibitor (H89) suppressed PDE11A variant-induced Tau phosphorylation formation. This study offers insight into the involvement of Tau phosphorylation via the cAMP/PKA pathway in EOAD pathogenesis and provides a potential new target for intervention.


Assuntos
Doença de Alzheimer , 3',5'-GMP Cíclico Fosfodiesterases/genética , Doença de Alzheimer/genética , Exoma/genética , Humanos , Diester Fosfórico Hidrolases/genética , Diester Fosfórico Hidrolases/metabolismo , Sequenciamento do Exoma
19.
Funct Integr Genomics ; 23(2): 101, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36964864

RESUMO

Biodiversity is proposed as a sustainable alternative for the economic development of high-biodiversity regions. Especially in the field of biodiversity genomics, the development of low-cost DNA sequencing opens an opportunity for new actors beyond academia to engage in genomic sequencing. However, it is challenging to adequately compensate non-academic actors such as local populations for their contribution to the innovation process, preventing better bioeconomy development. Although many repositories register genomic data to support biodiversity research, they do not facilitate the fair sharing of economic benefits. In this work, we propose the creation of the Amazon Biobank, a community-based genetic database. We employed blockchain to build a transparent and verifiable log of transactions involving genomic data, and we used smart contracts to implement an internal monetary system for all participants who collect, insert, process, store, and validate genomic data. We also used peer-to-peer solutions to allow users with commodity computers to collaborate with the storage and distribution of DNA files. By combining emerging technologies, Amazon Biobank provides adequate benefit-sharing among all participants that collaborate with data, knowledge, and computational resources. It also provides traceability and auditability, allowing easy association between biotechnological research and DNA data. In addition, the solution is highly scalable and less dependent on the trust deposited in any system player. Therefore, Amazon Biobank can become an important stepping stone to unlock the potential of bioeconomy in rich ecosystems such as the Amazon Rainforest.


Assuntos
Bancos de Espécimes Biológicos , Ecossistema , Humanos , Genômica , Bases de Dados Genéticas , DNA
20.
Histopathology ; 83(2): 326-329, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36939112

RESUMO

AIMS: Simple Bone Cysts (SBCs) predominantly occur in long bones and 59% harbour NFATC2 rearrangements. Jaw SBC is rare and was previously referred to as traumatic bone cyst. It can rarely occur in association with cemento-osseous dysplasia (COD). To determine whether jaw SBCs represent the same entity as SBC of the long bones, or if they have a different molecular signature, we collected 48 jaw SBC cases of 47 patients to assess NFATC2 rearrangement. METHODS AND RESULTS: Out of the 48 cases, 36 could be used for fluorescence in-situ hybridization (FISH), of which nine (two of which associated with COD) were successful using an NFATC2 split probe. The remaining cases failed to show adequate FISH signals. All nine cases lacked NFATC2 rearrangement and five of these showed no detectable gene fusions using Archer FusionPlex. CONCLUSION: In our study, NFATC2 rearrangement is absent in solitary jaw SBC (n = 7) and COD-associated SBC (n = 2). Our findings suggest that SBC presenting in the jaw is molecularly different from SBC in long bones. Future molecular studies may confirm the absence of clonal molecular aberrations in SBC of the jaw which would support a non-neoplastic, reactive origin.


Assuntos
Cistos Ósseos , Fatores de Transcrição NFATC , Tumores Odontogênicos , Humanos , Cistos Ósseos/genética , Tumores Odontogênicos/genética , Fatores de Transcrição NFATC/genética
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