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1.
Proc Natl Acad Sci U S A ; 121(7): e2312676121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38324566

RESUMO

To facilitate analysis and sharing of mass spectrometry (MS)-based proteomics data, we created online tools called CURTAIN (https://curtain.proteo.info) and CURTAIN-PTM (https://curtainptm.proteo.info) with an accompanying series of video tutorials (https://www.youtube.com/@CURTAIN-me6hl). These are designed to enable non-MS experts to interactively peruse volcano plots and deconvolute primary experimental data so that replicates can be visualized in bar charts or violin plots and exported in publication-ready format. They also allow assessment of overall experimental quality by correlation matrix and profile plot analysis. After making a selection of protein "hits", the user can analyze known domain structure, AlphaFold predicted structure, reported interactors, relative expression as well as disease links. CURTAIN-PTM permits analysis of all identified PTM sites on protein(s) of interest with selected databases. CURTAIN-PTM also links with the Kinase Library to predict upstream kinases that may phosphorylate sites of interest. We provide examples of the utility of CURTAIN and CURTAIN-PTM in analyzing how targeted degradation of the PPM1H Rab phosphatase that counteracts the Parkinson's LRRK2 kinase impacts cellular protein levels and phosphorylation sites. We also reanalyzed a ubiquitylation dataset, characterizing the PINK1-Parkin pathway activation in primary neurons, revealing data of interest not highlighted previously. CURTAIN and CURTAIN-PTM are free to use and open source, enabling researchers to share and maximize the impact of their proteomics data. We advocate that MS data published in volcano plot format be reported containing a shareable CURTAIN weblink, thereby allowing readers to better analyze and exploit the data.


Assuntos
Espectrometria de Massas , Proteômica , Software , Internet , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas/análise , Proteômica/métodos
2.
Proc Natl Acad Sci U S A ; 120(20): e2219953120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155866

RESUMO

The Golgi is a membrane-bound organelle that is essential for protein and lipid biosynthesis. It represents a central trafficking hub that sorts proteins and lipids to various destinations or for secretion from the cell. The Golgi has emerged as a docking platform for cellular signaling pathways including LRRK2 kinase whose deregulation leads to Parkinson disease. Golgi dysfunction is associated with a broad spectrum of diseases including cancer, neurodegeneration, and cardiovascular diseases. To allow the study of the Golgi at high resolution, we report a rapid Golgi immunoprecipitation technique (Golgi-IP) to isolate intact Golgi mini-stacks for subsequent analysis of their content. By fusing the Golgi-resident protein TMEM115 to three tandem HA epitopes (GolgiTAG), we purified the Golgi using Golgi-IP with minimal contamination from other compartments. We then established an analysis pipeline using liquid chromatography coupled with mass spectrometry to characterize the human Golgi proteome, metabolome, and lipidome. Subcellular proteomics confirmed known Golgi proteins and identified proteins not previously associated with the Golgi. Metabolite profiling established the human Golgi metabolome and revealed the enrichment of uridine-diphosphate (UDP) sugars and their derivatives, which is consistent with their roles in protein and lipid glycosylation. Furthermore, targeted metabolomics validated SLC35A2 as the subcellular transporter for UDP-hexose. Finally, lipidomics analysis showed that phospholipids including phosphatidylcholine, phosphatidylinositol, and phosphatidylserine are the most abundant Golgi lipids and that glycosphingolipids are enriched in this compartment. Altogether, our work establishes a comprehensive molecular map of the human Golgi and provides a powerful method to study the Golgi with high precision in health and disease.


Assuntos
Complexo de Golgi , Proteoma , Humanos , Complexo de Golgi/metabolismo , Cromatografia Líquida , Proteoma/metabolismo , Lipídeos , Difosfato de Uridina/metabolismo
3.
Mutagenesis ; 39(2): 146-155, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38183270

RESUMO

The two-test in vitro battery for genotoxicity testing (Ames and micronucleus) has in the majority of cases replaced the three-test battery (as two-test plus mammalian cell gene mutation assay) for the routine testing of chemicals, pharmaceuticals, cosmetics, and agrochemical metabolites originating from food and feed as well as from water treatment. The guidance for testing agrochemical groundwater metabolites, however, still relies on the three-test battery. Data collated in this study from 18 plant protection and related materials highlights the disparity between the often negative Ames and in vitro chromosome aberration data and frequently positive in vitro mammalian cell gene mutation assays. Sixteen of the 18 collated materials with complete datasets were Ames negative, and overall had negative outcomes in in vitro chromosome damage tests (weight of evidence from multiple tests). Mammalian cell gene mutation assays (HPRT and/or mouse lymphoma assay (MLA)) were positive in at least one test for every material with this data. Where both MLA and HPRT tests were performed on the same material, the HPRT seemed to give fewer positive responses. In vivo follow-up tests included combinations of comet assays, unscheduled DNA synthesis, and transgenic rodent gene mutation assays, all gave negative outcomes. The inclusion of mammalian cell gene mutation assays in a three-test battery for groundwater metabolites is therefore not justified and leads to unnecessary in vivo follow-up testing.


Assuntos
Hipoxantina Fosforribosiltransferase , Linfoma , Camundongos , Animais , Testes de Mutagenicidade , Ensaio Cometa , Roedores , Agroquímicos , Testes para Micronúcleos , Dano ao DNA
4.
J Clin Ultrasound ; 52(5): 588-599, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38567722

RESUMO

Deep learning techniques have become crucial in the detection of brain tumors but classifying numerous images is time-consuming and error-prone, impacting timely diagnosis. This can hinder the effectiveness of these techniques in detecting brain tumors in a timely manner. To address this limitation, this study introduces a novel brain tumor detection system. The main objective is to overcome the challenges associated with acquiring a large and well-classified dataset. The proposed approach involves generating synthetic Magnetic Resonance Imaging (MRI) images that mimic the patterns commonly found in brain MRI images. The system utilizes a dataset consisting of small images that are unbalanced in terms of class distribution. To enhance the accuracy of tumor detection, two deep learning models are employed. Using a hybrid ResNet+SE model, we capture feature distributions within unbalanced classes, creating a more balanced dataset. The second model, a tailored classifier identifies brain tumors in MRI images. The proposed method has shown promising results, achieving a high detection accuracy of 98.79%. This highlights the potential of the model as an efficient and cost-effective system for brain tumor detection.


Assuntos
Neoplasias Encefálicas , Aprendizado Profundo , Imageamento por Ressonância Magnética , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
5.
Dig Dis Sci ; 68(1): 284-290, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35467310

RESUMO

INTRODUCTION: Administration of antibiotics in patients with cirrhosis and upper gastrointestinal bleeding has been shown to improve outcomes. Little is known regarding optimum duration of prophylactic antibiotics. Seven days of antibiotics are generally recommended but very few studies have compared antibiotic duration to clinical outcomes in current available scientific literature. The goal of our study was to study the effect of shorter antibiotic duration on patient outcomes. METHODS: We conducted a retrospective cohort study of patients with cirrhosis presenting with upper GI bleeding at our institute from 2010 to 2018. Patients were divided into three cohorts based on duration of antibiotic administration for prophylaxis: 1-3 days of antibiotics, 4-6 days of antibiotics and 7 days or more of antibiotics. Rates of infection diagnosis within 30 days, rebleeding, and mortality were compared between the three groups with Chi square, Fisher Exact and Kruskall-Wallace tests. Multivariable analysis was conducted to evaluate independent risk factors for infection. RESULTS: Medical charts of 980 patients with cirrhosis and upper GI bleeding during the study period were reviewed. A total of 303 with upper gastrointestinal bleeding were included in the final sample, of these 243 patients received antibiotics for prophylaxis and were included for analysis. Seventy-seven patients received antibiotic therapy for 3 days or less, 69 patients for 4-6 days, and 97 patients longer than 6 days. The three groups were well matched in demographic and clinical variables. Twenty-seven patients developed infections within 30 days of bleeding. MELD-Na score at presentation and presence of ascites were associated with infection within 30 days. Rates of infection were not statistically different between the three antibiotic groups (p = 0.78). In the thirty days following the GI bleed, pneumonia was the most diagnosed infection (eleven patients) followed by urinary tract infections (eight patients). Four patients developed spontaneous bacterial peritonitis and three were diagnosed with bacteremia. There was no difference in time to infection (Kruskall Wallace test p = 0.75), early re-bleeding (p = 0.81), late re-bleeding (p = 0.37) and in-hospital mortality (p = 0.94) in the three groups. Six patients in the cohort developed C. Difficile infection; no patient in the short antibiotic group developed C. Difficile infection. CONCLUSION: Short course of antibiotics for prophylaxis (3 days) appears safe and adequate for prophylaxis in patients with cirrhosis with upper gastrointestinal bleeding if there is no active infection.


Assuntos
Infecções Bacterianas , Clostridioides difficile , Humanos , Antibioticoprofilaxia , Estudos Retrospectivos , Hemorragia Gastrointestinal/prevenção & controle , Hemorragia Gastrointestinal/complicações , Antibacterianos/uso terapêutico , Cirrose Hepática
6.
Biochem J ; 479(18): 1941-1965, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36040231

RESUMO

Leucine-rich-repeat-kinase 1 (LRRK1) and its homolog LRRK2 are multidomain kinases possessing a ROC-CORA-CORB containing GTPase domain and phosphorylate distinct Rab proteins. LRRK1 loss of function mutations cause the bone disorder osteosclerotic metaphyseal dysplasia, whereas LRRK2 missense mutations that enhance kinase activity cause Parkinson's disease. Previous work suggested that LRRK1 but not LRRK2, is activated via a Protein Kinase C (PKC)-dependent mechanism. Here we demonstrate that phosphorylation and activation of LRRK1 in HEK293 cells is blocked by PKC inhibitors including LXS-196 (Darovasertib), a compound that has entered clinical trials. We show multiple PKC isoforms phosphorylate and activate recombinant LRRK1 in a manner reversed by phosphatase treatment. PKCα unexpectedly does not activate LRRK1 by phosphorylating the kinase domain, but instead phosphorylates a cluster of conserved residues (Ser1064, Ser1074 and Thr1075) located within a region of the CORB domain of the GTPase domain. These residues are positioned at the equivalent region of the LRRK2 DK helix reported to stabilize the kinase domain αC-helix in the active conformation. Thr1075 represents an optimal PKC site phosphorylation motif and its mutation to Ala, blocked PKC-mediated activation of LRRK1. A triple Glu mutation of Ser1064/Ser1074/Thr1075 to mimic phosphorylation, enhanced LRRK1 kinase activity ∼3-fold. From analysis of available structures, we postulate that phosphorylation of Ser1064, Ser1074 and Thr1075 activates LRRK1 by promoting interaction and stabilization of the αC-helix on the kinase domain. This study provides new fundamental insights into the mechanism controlling LRRK1 activity and reveals a novel unexpected activation mechanism.


Assuntos
GTP Fosfo-Hidrolases , Proteínas Serina-Treonina Quinases , Cordyceps , GTP Fosfo-Hidrolases/metabolismo , Células HEK293 , Humanos , Leucina/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Mutação , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Isoformas de Proteínas/metabolismo , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Proteína Quinase C-alfa/metabolismo , Inibidores de Proteínas Quinases , Proteínas Serina-Treonina Quinases/genética
7.
J Am Chem Soc ; 144(37): 16930-16952, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36007011

RESUMO

Leucine-rich repeat kinase 2 (LRRK2) is one of the most promising targets for Parkinson's disease. LRRK2-targeting strategies have primarily focused on type 1 kinase inhibitors, which, however, have limitations as the inhibited protein can interfere with natural mechanisms, which could lead to undesirable side effects. Herein, we report the development of LRRK2 proteolysis targeting chimeras (PROTACs), culminating in the discovery of degrader XL01126, as an alternative LRRK2-targeting strategy. Initial designs and screens of PROTACs based on ligands for E3 ligases von Hippel-Lindau (VHL), Cereblon (CRBN), and cellular inhibitor of apoptosis (cIAP) identified the best degraders containing thioether-conjugated VHL ligand VH101. A second round of medicinal chemistry exploration led to qualifying XL01126 as a fast and potent degrader of LRRK2 in multiple cell lines, with DC50 values within 15-72 nM, Dmax values ranging from 82 to 90%, and degradation half-lives spanning from 0.6 to 2.4 h. XL01126 exhibits high cell permeability and forms a positively cooperative ternary complex with VHL and LRRK2 (α = 5.7), which compensates for a substantial loss of binary binding affinities to VHL and LRRK2, underscoring its strong degradation performance in cells. Remarkably, XL01126 is orally bioavailable (F = 15%) and can penetrate the blood-brain barrier after either oral or parenteral dosing in mice. Taken together, these experiments qualify XL01126 as a suitable degrader probe to study the noncatalytic and scaffolding functions of LRRK2 in vitro and in vivo and offer an attractive starting point for future drug development.


Assuntos
Barreira Hematoencefálica , Ubiquitina-Proteína Ligases , Animais , Camundongos , Barreira Hematoencefálica/metabolismo , Leucina , Ligantes , Inibidores de Proteínas Quinases/farmacologia , Proteólise , Sulfetos , Ubiquitina-Proteína Ligases/metabolismo
8.
Antimicrob Agents Chemother ; 66(4): e0173221, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35311524

RESUMO

Botulism is a rare, life-threatening paralytic disease caused by botulinum neurotoxin (BoNT). Available treatments including an equine antitoxin and human immune globulin are given postexposure and challenging to produce and administer. NTM-1633 is an equimolar mixture of 3 human IgG monoclonal antibodies, E1, E2, and E3, targeting BoNT serotype E (BoNT/E). This first-in-human study assessed the safety, tolerability, pharmacokinetics (PK), and immunogenicity of NTM-1633. This double-blind, single-center, placebo-controlled dose escalation study randomized 3 cohorts of healthy volunteers to receive a single intravenous dose of NTM-1633 (0.033, 0.165, or 0.330 mg/kg) or saline placebo. Safety monitoring included physical examinations, clinical laboratory studies, and vital signs. Blood sampling was performed at prespecified time points for PK and immunogenicity analyses. Twenty-four subjects received study product (18 NTM-1633; 6 placebo), and no deaths were reported. An unrelated serious adverse event was reported in a placebo subject. Adverse events in the NTM-1633 groups were generally mild and similar in frequency and severity to the placebo group, and no safety signal was identified. NTM-1633 has a favorable PK profile with a half-life >10 days for the 0.330 mg/kg dose and an approximately linear relationship with respect to maximum concentration and area under the concentration-time curve (AUC0→t). NTM-1633 also demonstrated low immunogenicity. NTM-1633 is well tolerated at the administered doses. The favorable safety, PK, and immunogenicity profile supports further development as a treatment for BoNT/E intoxication and postexposure prophylaxis.


Assuntos
Toxinas Botulínicas , Botulismo , Animais , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacocinética , Método Duplo-Cego , Cavalos , Humanos , Imunoglobulina G
9.
Nanotechnology ; 33(30)2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35395644

RESUMO

We investigated metal-organic vapor phase epitaxy grown droplet epitaxy (DE) and Stranski-Krastanov (SK) InAs/InP quantum dots (QDs) by cross-sectional scanning tunneling microscopy (X-STM). We present an atomic-scale comparison of structural characteristics of QDs grown by both growth methods proving that the DE yields more uniform and shape-symmetric QDs. Both DE and SKQDs are found to be truncated pyramid-shaped with a large and sharp top facet. We report the formation of localized etch pits for the first time in InAs/InP DEQDs with atomic resolution. We discuss the droplet etching mechanism in detail to understand the formation of etch pits underneath the DEQDs. A summary of the effect of etch pit size and position on fine structure splitting (FSS) is provided via thek·ptheory. Finite element (FE) simulations are performed to fit the experimental outward relaxation and lattice constant profiles of the cleaved QDs. The composition of QDs is estimated to be pure InAs obtained by combining both FE simulations and X-STM results. The preferential formation of {136} and {122} side facets was observed for the DEQDs. The formation of a DE wetting layer from As-P surface exchange is compared with the standard SKQDs wetting layer. The detailed structural characterization performed in this work provides valuable feedback for further growth optimization to obtain QDs with even lower FSS for applications in quantum technology.

10.
Biochem J ; 478(2): 299-326, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33367571

RESUMO

Mutations that increase the protein kinase activity of LRRK2 are one of the most common causes of familial Parkinson's disease. LRRK2 phosphorylates a subset of Rab GTPases within their Switch-II motif, impacting interaction with effectors. We describe and validate a new, multiplexed targeted mass spectrometry assay to quantify endogenous levels of LRRK2-phosphorylated Rab substrates (Rab1, Rab3, Rab8, Rab10, Rab35 and Rab43) as well as total levels of Rabs, LRRK2 and LRRK2-phosphorylated at the Ser910 and Ser935 biomarker sites. Exploiting this assay, we quantify for the first time the relative levels of each of the pRab proteins in different cells (mouse embryonic fibroblasts, human neutrophils) and mouse tissues (brain, kidney, lung and spleen). We define how these components are impacted by Parkinson's pathogenic mutations (LRRK2[R1441C] and VPS35[D620N]) and LRRK2 inhibitors. We find that the VPS35[D620N], but not LRRK2[R1441C] mutation, enhances Rab1 phosphorylation in a manner blocked by administration of an LRRK2 inhibitor, providing the first evidence that endogenous Rab1 is a physiological substrate for LRRK2. We exploit this assay to demonstrate that in Parkinson's patients with VPS35[D620N] mutations, phosphorylation of multiple Rab proteins (Rab1, Rab3, Rab8, Rab10 and Rab43) is elevated. We highlight the benefits of this assay over immunoblotting approaches currently deployed to assess LRRK2 Rab signalling pathway.


Assuntos
Biomarcadores/análise , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Espectrometria de Massas em Tandem/métodos , Proteínas rab de Ligação ao GTP/metabolismo , Animais , Biomarcadores/metabolismo , Fibroblastos/metabolismo , Humanos , Imunoprecipitação/métodos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/antagonistas & inibidores , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Limite de Detecção , Camundongos Mutantes , Mutação , Doença de Parkinson/genética , Fosforilação , Serina/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
11.
Biochem J ; 478(3): 553-578, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33459343

RESUMO

Autosomal dominant mutations in LRRK2 that enhance kinase activity cause Parkinson's disease. LRRK2 phosphorylates a subset of Rab GTPases including Rab8A and Rab10 within its effector binding motif. Here, we explore whether LRRK1, a less studied homolog of LRRK2 that regulates growth factor receptor trafficking and osteoclast biology might also phosphorylate Rab proteins. Using mass spectrometry, we found that in LRRK1 knock-out cells, phosphorylation of Rab7A at Ser72 was most impacted. This residue lies at the equivalent site targeted by LRRK2 on Rab8A and Rab10. Accordingly, recombinant LRRK1 efficiently phosphorylated Rab7A at Ser72, but not Rab8A or Rab10. Employing a novel phospho-specific antibody, we found that phorbol ester stimulation of mouse embryonic fibroblasts markedly enhanced phosphorylation of Rab7A at Ser72 via LRRK1. We identify two LRRK1 mutations (K746G and I1412T), equivalent to the LRRK2 R1441G and I2020T Parkinson's mutations, that enhance LRRK1 mediated phosphorylation of Rab7A. We demonstrate that two regulators of LRRK2 namely Rab29 and VPS35[D620N], do not influence LRRK1. Widely used LRRK2 inhibitors do not inhibit LRRK1, but we identify a promiscuous inhibitor termed GZD-824 that inhibits both LRRK1 and LRRK2. The PPM1H Rab phosphatase when overexpressed dephosphorylates Rab7A. Finally, the interaction of Rab7A with its effector RILP is not affected by LRRK1 phosphorylation and we observe that maximal stimulation of the TBK1 or PINK1 pathway does not elevate Rab7A phosphorylation. Altogether, these findings reinforce the idea that the LRRK enzymes have evolved as major regulators of Rab biology with distinct substrate specificity.


Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Fibroblastos , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/antagonistas & inibidores , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/imunologia , Camundongos , Camundongos Knockout , Fosfoproteínas Fosfatases/metabolismo , Fosforilação , Fosfosserina/metabolismo , Proteínas Quinases/deficiência , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Organismos Livres de Patógenos Específicos , Acetato de Tetradecanoilforbol/farmacologia
12.
Molecules ; 28(1)2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36615362

RESUMO

A topological index (TI) is a real number that defines the relationship between a chemical structure and its properties and remains invariant under graph isomorphism. TIs defined for chemical structures are capable of predicting physical properties, chemical reactivity and biological activity. Several kinds of TIs have been defined and studied for different molecular structures. Graphene is the thinnest material known to man and is also extremely strong while being a good conductor of heat and electricity. With such unique features, graphene and its derivatives have found commercial uses and have also fascinated theoretical chemists. In this article, the neighbourhood sum degree-based M-polynomial and entropy measures have been computed for graphene, graphyne and graphdiyne structures. The proper analytical expressions for these indices are derived. The obtained results will enable theoretical chemists to study these exciting structures further from a structural perspective.


Assuntos
Grafite , Relação Quantitativa Estrutura-Atividade , Humanos , Entropia , Estrutura Molecular , Algoritmos
13.
World J Microbiol Biotechnol ; 38(11): 207, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36008694

RESUMO

The plant growth-promoting rhizobacteria (PGPRs) improve plant growth and fitness by multiple direct (nitrogen fixation and phosphate solubilization) and indirect (inducing systematic resistance against phytopathogens, soil nutrient stabilization, and maintenance) mechanisms. Nevertheless, the mechanisms by which PGPRs promote plant growth in hot and arid environments remain poorly recorded. In this study, a comparative genome analysis of two phosphate solubilizing bacteria, Pseudomonas atacamensis SM1 and Pseudomonas toyotomiensis SM2, isolated from the rhizosphere of date palm was performed. The abundance of genes conferring stress tolerance (chaperones, heat shock genes, and chemotaxis) and supporting plant growth (plant growth hormone, root colonization, nitrogen fixation, and phosphate solubilization) were compared among the two isolates. This study further evaluated their functions, metabolic pathways, and evolutionary relationship. Results show that both bacterial strains have gene clusters required for plant growth promotion (phosphate solubilization and root colonization), but it is more abundant in P. atacamensis SM1 than in P. toyotomiensis SM2. Genes involved in stress tolerance (mcp, rbs, wsp, and mot), heat shock, and chaperones (hslJ and hslR) were also more common in P. atacamensis SM1. These findings suggest that P. atacamensis SM1could have better adaptability to the hot and arid environment owing to a higher abundance of chaperone genes and heat shock proteins. It may promote plant growth owing to a higher load of root colonization and phosphate solubilization genes and warrants further in vitro study.


Assuntos
Phoeniceae , Rizosfera , Bactérias/metabolismo , Ácidos Indolacéticos/metabolismo , Phoeniceae/metabolismo , Fosfatos/metabolismo , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Pseudomonas/metabolismo , Microbiologia do Solo
14.
Antimicrob Agents Chemother ; 65(7): e0232920, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33875433

RESUMO

Botulism is a rare, life-threatening paralytic disease caused by Clostridium botulinum neurotoxin (BoNT). Available treatments, including an equine antitoxin and human immune globulin, are given postexposure and challenging to produce and administer. NTM-1632 is an equimolar mixture of 3 human IgG monoclonal antibodies, B1, B2, and B3, targeting BoNT serotype B (BoNT/B). This first-in-human study assessed the safety, tolerability, pharmacokinetics (PK), and immunogenicity of NTM-1632. This double-blind, single-center, placebo-controlled dose escalation study randomized 3 cohorts of healthy volunteers to receive a single intravenous dose of NTM-1632 (0.033, 0.165, or 0.330 mg/kg) or saline placebo. Safety monitoring included physical examinations, clinical laboratory studies, and vital signs. Blood sampling was performed at prespecified time points for PK and immunogenicity analyses. Twenty-four subjects received study product (18 NTM-1632; 6 placebo), and no deaths or serious adverse events were reported. Adverse events in the NTM-1632 groups were generally mild and similar in frequency and severity to the placebo group, and no safety signal was identified. NTM-1632 has a favorable PK profile with a half-life of >20 days for the 0.330-mg/kg dose and an approximately linear relationship with respect to maximum concentration and area under the concentration-time curve (AUC0→t). NTM-1632 demonstrated low immunogenicity with only a few treatment-emergent antidrug antibody responses in the low and middle dosing groups and none at the highest dose. NTM-1632 is well tolerated at the administered doses. The favorable safety, PK, and immunogenicity profile of NTM-1632 supports further clinical development as a treatment for BoNT/B intoxication and postexposure prophylaxis. (This study has been registered at ClinicalTrials.gov under identifier NCT02779140.).


Assuntos
Anticorpos Monoclonais , Botulismo , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/uso terapêutico , Botulismo/tratamento farmacológico , Método Duplo-Cego , Voluntários Saudáveis , Humanos , Imunoglobulina G
15.
Acta Neuropathol ; 142(3): 475-494, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34125248

RESUMO

Heterozygous gain-of-kinase function variants in LRRK2 (leucine-rich repeat kinase 2) cause 1-2% of all cases of Parkinson's disease (PD) albeit with incomplete and age-dependent penetrance. All pathogenic LRRK2 mutations reside within the two catalytic domains of LRRK2-either in its kinase domain (e.g. G2019S) with modest effect or its ROC-COR GTPase domain (e.g. R1441G/H) with large effect on LRRK2 kinase activity. We have previously reported assays to interrogate LRRK2 kinase pathway activity in human bio-samples measuring phosphorylation of its endogenous substrate Rab10, that mirrors LRRK2 kinase activation status. Here, we isolated neutrophils from fresh peripheral blood from 101 participants including 42 LRRK2 mutation carriers (21 with the G2019S and 21 with the R1441G mutations), 27 patients with idiopathic PD, and 32 controls. Using a dual approach, LRRK2 dependent Rab10 phosphorylation at Threonine 73 (pRab10Thr73) was measured by quantitative multiplexed immunoblotting for pRab10Thr73/total Rab10 as well as targeted mass-spectrometry for absolute pRab10Thr73 occupancy. We found a significant over fourfold increase in pRab10Thr73 phosphorylation in carriers of the LRRK2 R1441G mutation irrespective of clinical disease status. The effect of the LRRK2 G2019S mutation did not reach statistical significance. Furthermore, we show that LRRK2 phosphorylation at Serine 935 is not a marker for LRRK2 kinase activity in human neutrophils. When analysing pRab10Thr73 phosphorylation in post-mortem brain samples, we observed overall high variability irrespective of clinical and LRRK2 mutation status and attributed this mainly to the adverse effect of the peri- and post-mortem period on the stability of posttranslational modifications such as protein phosphorylation. Overall, in vivo LRRK2 dependent pRab10Thr73 phosphorylation in human peripheral blood neutrophils is a specific, robust and promising biomarker for significant LRRK2 kinase hyperactivation, as with the LRRK2 R1441G mutation. Additional readouts and/or assays may be needed to increase sensitivity to detect modest LRRK2 kinase activation, as with the LRRK2 G2019S mutation. Our assays could be useful for patient stratification and target engagement studies for LRRK2 kinase inhibitors.


Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Mutação/genética , Neutrófilos/metabolismo , Proteínas rab de Ligação ao GTP/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Autopsia , Biomarcadores , Feminino , Heterozigoto , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/genética , Doença de Parkinson/patologia , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Processamento de Proteína Pós-Traducional
16.
Plant Cell ; 30(7): 1645-1660, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29891568

RESUMO

Long-lived perennial plants, with distinctive habits of inter-annual growth, defense, and physiology, are of great economic and ecological importance. However, some biological mechanisms resulting from genome duplication and functional divergence of genes in these systems remain poorly studied. Here, we discovered an association between a poplar (Populus trichocarpa) 5-enolpyruvylshikimate 3-phosphate synthase gene (PtrEPSP) and lignin biosynthesis. Functional characterization of PtrEPSP revealed that this isoform possesses a helix-turn-helix motif in the N terminus and can function as a transcriptional repressor that regulates expression of genes in the phenylpropanoid pathway in addition to performing its canonical biosynthesis function in the shikimate pathway. We demonstrated that this isoform can localize in the nucleus and specifically binds to the promoter and represses the expression of a SLEEPER-like transcriptional regulator, which itself specifically binds to the promoter and represses the expression of PtrMYB021 (known as MYB46 in Arabidopsis thaliana), a master regulator of the phenylpropanoid pathway and lignin biosynthesis. Analyses of overexpression and RNAi lines targeting PtrEPSP confirmed the predicted changes in PtrMYB021 expression patterns. These results demonstrate that PtrEPSP in its regulatory form and PtrhAT form a transcriptional hierarchy regulating phenylpropanoid pathway and lignin biosynthesis in Populus.


Assuntos
3-Fosfoshikimato 1-Carboxiviniltransferase/metabolismo , Populus/metabolismo , 3-Fosfoshikimato 1-Carboxiviniltransferase/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Populus/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Toxicol Appl Pharmacol ; 428: 115673, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34364948

RESUMO

Pegbelfermin (PGBF) is a PEGylated fibroblast growth factor 21 (FGF21) analogue in development for treatment of nonalcoholic steatohepatitis (NASH). Mouse models highlight potential utility of FGF21 in NASH, but also suggest negative effects on bone, though these findings are confounded by profound FGF21-related decreases in body mass/growth. This study aimed to profile PGBF-related bone effects in adult nonhuman primates after long-term, clinically-relevant exposures. Adult male cynomolgus monkeys received weekly subcutaneous PGBF (0.3, 0.75 mg/kg) or control injections for 1 year (n = 5/group). Assessments included body weight, clinical chemistry, adiponectin levels, bone turnover biomarkers, skeletal radiography, pharmacokinetics, immunogenicity, and histopathology. Bone densitometry and body composition were evaluated in vivo and/or ex vivo with dual-energy x-ray absorptiometry, peripheral quantitative computed tomography, and biomechanical strength testing. After 1 year of PGBF administration, there was clear evidence of sustained PGBF pharmacology in monkeys (peak increase in serum adiponectin of 1.7× and 2.35× pretest at 0.3 and 0.75 mg/kg PGBF, respectively) and decreased body weight compared with control at exposures comparable to those tested in humans. At 0.75 mg/kg PGBF, pharmacologically-mediated reductions in lean mass, lean area, and fat area were observed relative to controls. There were no PGBF-related effects on bone biomarkers, radiography, densitometry, or strength. Together, these data demonstrate that PGBF did not adversely alter bone metabolism, density, or strength following 1 year of dosing at clinically relevant (0.7-2.2× human AUC[0-168 h] at 20 mg once weekly), pharmacologically-active exposures in adult monkeys, suggesting a low potential for negative effects on bone quality in adult humans.


Assuntos
Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Fatores de Crescimento de Fibroblastos/análogos & derivados , Polietilenoglicóis/administração & dosagem , Animais , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Esquema de Medicação , Fatores de Crescimento de Fibroblastos/administração & dosagem , Fatores de Crescimento de Fibroblastos/química , Haplorrinos , Macaca fascicularis , Masculino , Polietilenoglicóis/química , Fatores de Tempo
18.
Arch Microbiol ; 203(1): 219-231, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32803348

RESUMO

Goldfish farming gained more attention among the ornamental fishes in aquaculture industry. The occurrence of bacterial infections and further antimicrobial treatment lead to the major crisis of antibiotic resistance in aquaculture. We have isolated diverse enterobacteriaceae groups which affect the goldfish and identified their response towards 46 antimicrobials of 15 different classes. Thirteen significant bacterial isolates such as Edwardsiella tarda, Serratia marcescens, Klebsiella aerogenes, Proteus penneri, P. hauseri, Enterobacter cloacae, E. cancerogenus, E. ludwigii, Citrobacter freundii, E. coli, Kluyvera cryocrescens, Plesiomonas shigelloides and Providencia vermicola were recovered from the infected fish with the Shannon-wiener diversity index of 2.556. Multiple antibiotic resistance (MAR) index was found to be maximum for P. penneri (0.87) and minimum for C. freundii and E. cloacae (0.22), highlighting the hyper antibiotic selection pressure in the farm. The minimum concentration of antibiotics required to inhibit most of the resistant isolates was found to be > 256 mcg/ml. All the isolates were susceptible towards ciprofloxacin. Plasmid curing and further AMR tests could reveal the location of antibiotic resistance genes mainly as plasmids which determine the large extent of AMR spread through horizontal gene transfer. This study is the first of its kind to investigate the antimicrobial resistance profile of enterobacteriaceae recovered from goldfish, before and after plasmid curing.


Assuntos
Antibacterianos/farmacologia , Infecções por Enterobacteriaceae/veterinária , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Doenças dos Peixes/microbiologia , Carpa Dourada/microbiologia , Animais , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Água Doce , Transferência Genética Horizontal/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , beta-Lactamases/genética
19.
J Appl Toxicol ; 41(6): 915-927, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33124094

RESUMO

The regulatory community is transitioning to the use of nonanimal methods for dermal sensitization assessments; however, some in vitro assays have limitations in their domain of applicability depending on the properties of chemicals being tested. This study explored the utility of epidermal sensitization assay (EpiSensA) to evaluate the sensitization potential of complex and/or "difficult to test" chemicals. Assay performance was evaluated by testing a set of 20 test chemicals including 10 methacrylate esters, 5 silicone-based compounds, 3 crop protection formulations, and 2 surfactant mixtures; each had prior in vivo data plus some in silico and in vitro data. Using the weight of evidence (WoE) assessments by REACH Lead Registrants, 14 of these chemicals were sensitizers and, six were nonsensitizers based on in vivo studies (local lymph node assay [LLNA] and/or guinea pig studies). The EpiSensA correctly predicted 16/20 materials with three test materials as false positive and one silane as false negative. This silane, classified as weak sensitizer via LLNA, also gave a "false negative" result in the KeratinoSens™ assay. Overall, consistent with prior evaluations, the EpiSensA demonstrated an accuracy level of 80% relative to available in vivo WoE assessments. In addition, potency classification based on the concentration showing positive marker gene expression of EpiSensA was performed. The EpiSensA correctly predicted the potency for all seven sensitizing methacrylates classified as weak potency via LLNA (EC3 ≥ 10%). In summary, EpiSensA could identify dermal sensitization potential of these test substances and mixtures, and continues to show promise as an in vitro alternative method for dermal sensitization.


Assuntos
Agroquímicos/toxicidade , Testes Cutâneos , Alérgenos , Alternativas aos Testes com Animais/métodos , Animais , Bioensaio , Linhagem Celular , Dermatite Alérgica de Contato , Epiderme , Cobaias , Haptenos , Humanos , Técnicas In Vitro , Ensaio Local de Linfonodo , Pele
20.
Eur Spine J ; 30(7): 2069-2081, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33748882

RESUMO

PURPOSE: Inappropriate use of MRI leads to increasing interventions and surgeries for low back pain (LBP). We probed the potential effects of a routine MRI report on the patient's perception of his spine and functional outcome of treatment. An alternate 'clinical reporting' was developed and tested for benefits on LBP perception. METHODS: In Phase-I, 44 LBP patients were randomized to Group A who had a factual explanation of their MRI report or Group B, who were reassured that the MRI findings showed normal changes. The outcome was compared at 6 weeks by VAS, PSEQ-2, and SF-12. In Phase-II, clinical reporting was developed, avoiding potential catastrophizing terminologies. In Phase-III, 20 MRIs were reported by both routine and clinical methods. The effects of the two methods were tested on four categories of health care professionals (HCP) who read them blinded on their assessment of severity of disease, possible treatment required, and the probability of surgery. RESULTS: Both groups were comparable initial by demographics and pain. After 6 weeks of treatment, Group A had a more negative perception of their spinal condition, increased catastrophization, decreased pain improvement, and poorer functional status(p = significant for all). The alternate method of clinical reporting had significant benefits in assessment of lesser severity of the disease, shift to lesser severity of intervention and surgery in three groups of HCPs. CONCLUSION: Routine MRI reports produce a negative perception and poor functional outcomes in LBP. Focussed clinical reporting had significant benefits, which calls for the need for 'clinical reporting' rather than 'Image reporting'.


Assuntos
Dor Lombar , Cirurgiões , Catastrofização , Humanos , Dor Lombar/diagnóstico por imagem , Imageamento por Ressonância Magnética , Projetos de Pesquisa
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