Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 359
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Brief Bioinform ; 23(6)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36124775

RESUMO

Pan-genome analyses of metagenome-assembled genomes (MAGs) may suffer from the known issues with MAGs: fragmentation, incompleteness and contamination. Here, we conducted a critical assessment of pan-genomics of MAGs, by comparing pan-genome analysis results of complete bacterial genomes and simulated MAGs. We found that incompleteness led to significant core gene (CG) loss. The CG loss remained when using different pan-genome analysis tools (Roary, BPGA, Anvi'o) and when using a mixture of MAGs and complete genomes. Contamination had little effect on core genome size (except for Roary due to in its gene clustering issue) but had major influence on accessory genomes. Importantly, the CG loss was partially alleviated by lowering the CG threshold and using gene prediction algorithms that consider fragmented genes, but to a less degree when incompleteness was higher than 5%. The CG loss also led to incorrect pan-genome functional predictions and inaccurate phylogenetic trees. Our main findings were supported by a study of real MAG-isolate genome data. We conclude that lowering CG threshold and predicting genes in metagenome mode (as Anvi'o does with Prodigal) are necessary in pan-genome analysis of MAGs. Development of new pan-genome analysis tools specifically for MAGs are needed in future studies.


Assuntos
Genoma Bacteriano , Metagenoma , Filogenia , Genômica , Análise de Sequência de DNA/métodos , Metagenômica/métodos
2.
Appl Environ Microbiol ; 90(9): e0122424, 2024 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-39177328

RESUMO

Given the vast quantity of oil and gas input to the marine environment annually, hydrocarbon degradation by marine microorganisms is an essential ecosystem service. Linkages between taxonomy and hydrocarbon degradation capabilities are largely based on cultivation studies, leaving a knowledge gap regarding the intrinsic ability of uncultured marine microbes to degrade hydrocarbons. To address this knowledge gap, metagenomic sequence data from the Deepwater Horizon (DWH) oil spill deep-sea plume was assembled to which metagenomic and metatranscriptomic reads were mapped. Assembly and binning produced new DWH metagenome-assembled genomes that were evaluated along with their close relatives, all of which are from the marine environment (38 total). These analyses revealed globally distributed hydrocarbon-degrading microbes with clade-specific substrate degradation potentials that have not been reported previously. For example, methane oxidation capabilities were identified in all Cycloclasticus. Furthermore, all Bermanella encoded and expressed genes for non-gaseous n-alkane degradation; however, DWH Bermanella encoded alkane hydroxylase, not alkane 1-monooxygenase. All but one previously unrecognized DWH plume member in the SAR324 and UBA11654 have the capacity for aromatic hydrocarbon degradation. In contrast, Colwellia were diverse in the hydrocarbon substrates they could degrade. All clades encoded nutrient acquisition strategies and response to cold temperatures, while sensory and acquisition capabilities were clade specific. These novel insights regarding hydrocarbon degradation by uncultured planktonic microbes provides missing data, allowing for better prediction of the fate of oil and gas when hydrocarbons are input to the ocean, leading to a greater understanding of the ecological consequences to the marine environment.IMPORTANCEMicrobial degradation of hydrocarbons is a critically important process promoting ecosystem health, yet much of what is known about this process is based on physiological experiments with a few hydrocarbon substrates and cultured microbes. Thus, the ability to degrade the diversity of hydrocarbons that comprise oil and gas by microbes in the environment, particularly in the ocean, is not well characterized. Therefore, this study aimed to utilize non-cultivation-based 'omics data to explore novel genomes of uncultured marine microbes involved in degradation of oil and gas. Analyses of newly assembled metagenomic data and previously existing genomes from other marine data sets, with metagenomic and metatranscriptomic read recruitment, revealed globally distributed hydrocarbon-degrading marine microbes with clade-specific substrate degradation potentials that have not been previously reported. This new understanding of oil and gas degradation by uncultured marine microbes suggested that the global ocean harbors a diversity of hydrocarbon-degrading bacteria, which can act as primary agents regulating ecosystem health.


Assuntos
Bactérias , Biodegradação Ambiental , Hidrocarbonetos , Água do Mar , Hidrocarbonetos/metabolismo , Água do Mar/microbiologia , Bactérias/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Oceanos e Mares , Metagenoma , Metagenômica , Poluição por Petróleo , Filogenia
3.
BMC Microbiol ; 24(1): 228, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943070

RESUMO

BACKGROUND: Mangroves are complex and dynamic coastal ecosystems under frequent fluctuations in physicochemical conditions related to the tidal regime. The frequent variation in organic matter concentration, nutrients, and oxygen availability, among other factors, drives the microbial community composition, favoring syntrophic populations harboring a rich and diverse, stress-driven metabolism. Mangroves are known for their carbon sequestration capability, and their complex and integrated metabolic activity is essential to global biogeochemical cycling. Here, we present a metabolic reconstruction based on the genomic functional capability and flux profile between sympatric MAGs co-assembled from a tropical restored mangrove. RESULTS: Eleven MAGs were assigned to six Bacteria phyla, all distantly related to the available reference genomes. The metabolic reconstruction showed several potential coupling points and shortcuts between complementary routes and predicted syntrophic interactions. Two metabolic scenarios were drawn: a heterotrophic scenario with plenty of carbon sources and an autotrophic scenario with limited carbon sources or under inhibitory conditions. The sulfur cycle was dominant over methane and the major pathways identified were acetate oxidation coupled to sulfate reduction, heterotrophic acetogenesis coupled to carbohydrate catabolism, ethanol production and carbon fixation. Interestingly, several gene sets and metabolic routes similar to those described for wastewater and organic effluent treatment processes were identified. CONCLUSION: The mangrove microbial community metabolic reconstruction reflected the flexibility required to survive in fluctuating environments as the microhabitats created by the tidal regime in mangrove sediments. The metabolic components related to wastewater and organic effluent treatment processes identified strongly suggest that mangrove microbial communities could represent a resourceful microbial model for biotechnological applications that occur naturally in the environment.


Assuntos
Bactérias , Microbiota , Áreas Alagadas , Microbiota/genética , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Filogenia , Processos Heterotróficos , Ciclo do Carbono , Carbono/metabolismo , Metano/metabolismo , Processos Autotróficos , Redes e Vias Metabólicas/genética
4.
Eur J Neurol ; 31(3): e16164, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38015467

RESUMO

BACKGROUND: Anti-myelin-associated glycoprotein (MAG) neuropathy is a debilitating demyelinating polyneuropathy with no approved therapies. Our primary objective was to ascertain lenalidomide safety and maximum tolerated dose (MTD) in anti-MAG neuropathy. METHODS: This phase 1b, open-label, single-arm, dose-finding trial was conducted from 2019 through 2022. The original design included a dose-escalation/extension phase followed by a dose-expansion phase. Three doses of lenalidomide were evaluated: 10, 15, and 25 mg. The main outcome was the MTD. RESULTS: Eleven patients enrolled (10 men), with a mean age of 67.6 years (SD = 6.18, range 58-77 years) and mean disease duration of 8.5 years (SD = 10.9, range 1-40 years). The study terminated early due to higher-than-expected non-dose-limiting toxicity venous thromboembolism (VTE) events. The calculated MTD was 25 mg (posterior mean of toxicity probability was 0.01 with a 95% credible interval of 0.00, 0.06), but a recommended phase 2 dose of 15 mg was advised. For secondary exploratory outcomes, only EQ-5D (-0.95, 95% CI -1.81 to -0.09) and total IgM (-162 mg/dL, 95% CI -298 to -26) showed signs of improvement by month 12. CONCLUSIONS: Lenalidomide was associated with higher-than-expected VTE events in anti-MAG neuropathy patients, despite a calculated MTD of 25 mg. A recommended phase 2 dose of 15 mg was advised. Lenalidomide did not improve disability or impairment at 12 months, although this study was not powered for efficacy. The risks of long term lenalidomide may outweigh benefit for patients with anti-MAG neuropathy. Any future efficacy study should address VTE risk, as current myeloma guidelines appear inadequate. TRIAL REGISTRATION: Lenalidomide in Anti-MAG Neuropathy: Phase 1b Study, ClinicalTrials.gov Identifier: NCT03701711, https://clinicaltrials.gov/ct2/show/NCT03701711. First submitted October 10, 2018. First patient enrolled in January 2019.


Assuntos
Doenças do Sistema Nervoso Periférico , Tromboembolia Venosa , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Glicoproteínas , Lenalidomida/administração & dosagem , Lenalidomida/efeitos adversos , Dose Máxima Tolerável , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Tromboembolia Venosa/induzido quimicamente , Tromboembolia Venosa/tratamento farmacológico
5.
BMC Neurol ; 24(1): 320, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237863

RESUMO

Neurolymphomatosis (NL) is a rare neurologic manifestation of non-Hodgkin lymphoma (NHL) with poor prognosis. Investigations including MRI, PET/CT, nerve biopsy and cerebrospinal fluid (CSF) analysis can aid the diagnosis of NL. In this study, we presented a case of NL with co-existing myelin-associated glycoprotein (MAG) antibody. The patient first presented with symptoms of peripheral neuropathy involving multiple cranial nerves and cauda equina, and later developed obstructive hydrocephalus and deep matter lesions. He also had persistently positive MAG antibody, but did not develop electrophysiologically proven neuropathy and monoclonal immunoglobulin. The final brain biopsy confirmed diffuse large B cell lymphoma.


Assuntos
Glicoproteína Associada a Mielina , Neurolinfomatose , Humanos , Masculino , Neurolinfomatose/diagnóstico por imagem , Neurolinfomatose/diagnóstico , Glicoproteína Associada a Mielina/imunologia , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/complicações , Idoso , Autoanticorpos/sangue , Autoanticorpos/imunologia , Autoanticorpos/líquido cefalorraquidiano
6.
J Biochem Mol Toxicol ; 38(4): e23638, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38613466

RESUMO

The pancreas is a heterocrine gland that has both exocrine and endocrine parts. Most pancreatic cancer begins in the cells that line the ducts of the pancreas and is called pancreatic ductal adenocarcinoma (PDAC). PDAC is the most encountered pancreatic cancer type. One of the most important characteristic features of PDAC is neuropathy which is primarily due to perineural invasion (PNI). PNI develops tumor microenvironment which includes overexpression of fibroblasts cells, macrophages, as well as angiogenesis which can be responsible for neuropathy pain. In tumor microenvironment inactive fibroblasts are converted into an active form that is cancer-associated fibroblasts (CAFs). Neurotrophins they also increase the level of Substance P, calcitonin gene-related peptide which is also involved in pain. Matrix metalloproteases are the zinc-associated proteases enzymes which activates proinflammatory interleukin-1ß into its activated form and are responsible for release and activation of Substance P which is responsible for neuropathic pain by transmitting pain signal via dorsal root ganglion. All the molecules and their role in being responsible for neuropathic pain are described below.


Assuntos
Neuralgia , Neoplasias Pancreáticas , Humanos , Substância P , Neuralgia/etiologia , Pâncreas , Neoplasias Pancreáticas/complicações , Fibroblastos , Microambiente Tumoral
7.
BMC Med Imaging ; 24(1): 94, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649862

RESUMO

BACKGROUND: Large field of view CZT SPECT cameras with a ring geometry are available for some years now. Thanks to their good sensitivity and high temporal resolution, general dynamic SPECT imaging may be performed more easily, without resorting to dedicated systems. To evaluate the dynamic SPECT imaging by such cameras, we have performed an in vivo pilot study to analyze the kidney function of a pig and compare the results to standard dynamic planar imaging by a conventional gamma camera. METHODS: A 7-week-old (12 kg) female Landrace pig was injected with [99mTc]Tc-MAG3 and a 30 min dynamic SPECT acquisition of the kidneys was performed on a CZT ring camera. A fast SPECT/CT was acquired with the same camera immediately after the dynamic SPECT, without moving the pig, and used for attenuation correction and drawing regions of interest. The next day the same pig underwent a dynamic planar imaging of the kidneys by a conventional 2-head gamma camera. The dynamic SPECT acquisition was reconstructed using a MLEM algorithm with up to 20 iterations, with and without attenuation correction. Time-activity curves of the total counts of each kidney were extracted from 2D and 3D dynamic images. An adapted 2-compartment model was derived to fit the data points and extract physiological parameters. Comparison of these parameters was performed between the different reconstructions and acquisitions. RESULTS: Time-activity curves were nicely fitted with the 2-compartment model taking into account the anesthesia and bladder filling. Kidney physiological parameters were found in agreement with literature values. Good agreement of these parameters was obtained for the right kidney between dynamic SPECT and planar imaging. Regional analysis of the kidneys can be performed in the case of the dynamic SPECT imaging and provided good agreement with the whole kidney results. CONCLUSIONS: Dynamic SPECT imaging is feasible with CZT swiveling-detector ring cameras and provides results in agreement with dynamic planar imaging by conventional gamma cameras. Regional analysis of organs uptake and clearance becomes possible. Further studies are required regarding the optimization of acquisition and reconstruction parameters to improve image quality and enable absolute quantification.


Assuntos
Câmaras gama , Rim , Telúrio , Tomografia Computadorizada de Emissão de Fóton Único , Zinco , Animais , Projetos Piloto , Rim/diagnóstico por imagem , Feminino , Suínos , Tomografia Computadorizada de Emissão de Fóton Único/instrumentação , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Cádmio , Tecnécio Tc 99m Mertiatida , Algoritmos , Compostos Radiofarmacêuticos
8.
Food Microbiol ; 117: 104372, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37919016

RESUMO

Interest in fermented foods, especially plant-based ones, has increased considerably in the last decade. Miso-a Japanese paste traditionally fermented with soybeans, salt, and koji (Aspergillus oryzae grown on grains or beans)-has gained attention among chefs for its rich flavour and versatility. Some chefs have even been experimenting with making novel misos with untraditional substrates to create new flavours. Such novel fermented foods also offer new scientific opportunities. To explore the microbial diversity of these new traditional foods, we sampled six misos made by the team at a leading restaurant called Noma in Copenhagen (Denmark), using yellow peas (including a nixtamalised treatment), lupin seeds, Swedish Vreta peas, grey peas, and Gotland lentils as substrates. All misos were made with the same recipe and fermented for 3 months at 28 °C. Samples were collected at the end of fermentation for subsequent shotgun metagenomic sequencing and a genome-resolved metagenomic analysis. The taxonomic profile of the samples revealed the presence of koji mould (A. oryzae) and Bacillus amyloliquefaciens in all misos. Various species of the genera Latilactobacillus, Lactiplantibacillus, Pediococcus and Staphylococcus were also detected. The Metagenome-Assembled Genomes (MAGs) revealed genomic sequences belonging to 12 different species and functional analyses of these MAGs were performed. Notably, we detected the presence of Exiguobacterium-the first reported instance of the genus in miso-and Average Nucleotide Identity (ANI) analyses suggest a potentially new species. We hope these results will improve the scientific literature on misos and contribute to developing novel fermented plant-based foods.


Assuntos
Fabaceae , Alimentos Fermentados , Alimentos de Soja , Glycine max , Metagenômica , Aromatizantes/análise , Fermentação
9.
Mar Drugs ; 22(6)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38921569

RESUMO

Microalgae are currently considered an attractive source of highly valuable metabolites potentially exploitable as anticancer agents, nutraceuticals and cosmeceuticals and for bioenergy purposes. Their ease of culturing and their high growth rates further promote their use as raw material for the production of specialty products. In the present paper, we focused our attention on specific glycerol-based lipid compounds, monoacylglycerols (MAGs), which displayed in our previous studies a selective cytotoxic activity against the haematological U-937 and the colon HCT-116 cancer cell lines. Here, we performed a quali/quantitative analysis of MAGs and total fatty acids (FAs) along with a profiling of the main lipid classes in a panel of 12 microalgal species, including diatoms and dinoflagellates. Our results highlight an inter- and intraspecific variability of MAG profile in the selected strains. Among them, Skeletonema marinoi (strain FE7) has emerged as the most promising source for possible biotechnological production of MAGs.


Assuntos
Ácidos Graxos , Microalgas , Monoglicerídeos , Microalgas/metabolismo , Humanos , Monoglicerídeos/farmacologia , Ácidos Graxos/metabolismo , Diatomáceas/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Organismos Aquáticos , Dinoflagellida/metabolismo , Dinoflagellida/química , Células HCT116
10.
Mikrochim Acta ; 191(2): 104, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38236334

RESUMO

A lateral flow assay (LFA) strip based on dual 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB)-encoded satellite Fe3O4@Au (Mag@Au) SERS tags with nanogap is reported for  ultrasensitive and simultaneous diagnosis of two SARS-CoV-2 functional proteins. Composed of Fe3O4 core, satellite gold shell with nanogaps, and double-layer DTNB, the Mag@Au nanoparticles with an average size of 238 nm were designed as multifunctional tags to efficiently enrich the target SARS-CoV-2 protein from complex samples, significantly enhancing the SERS signal of the LFA strip and provide quantitative SERS detection of analyte on test lines. The developed dual DTNB-encoded satellite Mag@Au-based LFA allowed simultaneous quantification of spike (S) protein and nucleocapsid (NP) protein with detection limits of 23 pg mL-1 and 2 pg mL-1, respectively, lower than commercial ELISA kits and reported SERS-LFA detection system-based Au NPs and Fe3O4@3 nm Au MNPs. This magnetic SERS-LFA also showed high performance of multi-variant strain detection and further distinguished clinical samples of Omicron variant infection, demonstrating the potential of in situ detection of respiratory virus diseases.


Assuntos
COVID-19 , Nanopartículas Metálicas , Humanos , COVID-19/diagnóstico , Ácido Ditionitrobenzoico , Ouro , SARS-CoV-2
11.
Brief Bioinform ; 22(5)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33758906

RESUMO

Recent advances in high-throughput sequencing technologies and computational methods have added a new dimension to metagenomic data analysis i.e. genome-resolved metagenomics. In general terms, it refers to the recovery of draft or high-quality microbial genomes and their taxonomic classification and functional annotation. In recent years, several studies have utilized the genome-resolved metagenome analysis approach and identified previously unknown microbial species from human and environmental metagenomes. In this review, we describe genome-resolved metagenome analysis as a series of four necessary steps: (i) preprocessing of the sequencing reads, (ii) de novo metagenome assembly, (iii) genome binning and (iv) taxonomic and functional analysis of the recovered genomes. For each of these four steps, we discuss the most commonly used tools and the currently available pipelines to guide the scientific community in the recovery and subsequent analyses of genomes from any metagenome sample. Furthermore, we also discuss the tools required for validation of assembly quality as well as for improving quality of the recovered genomes. We also highlight the currently available pipelines that can be used to automate the whole analysis without having advanced bioinformatics knowledge. Finally, we will highlight the most widely adapted and actively maintained tools and pipelines that can be helpful to the scientific community in decision making before they commence the analysis.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Genoma Microbiano , Metagenoma , Metagenômica/métodos , Microbiota/genética , Fezes/microbiologia , Genitália/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Boca/microbiologia , Análise de Sequência de DNA , Pele/microbiologia , Microbiologia do Solo , Microbiologia da Água
12.
Muscle Nerve ; 68(6): 823-832, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37602932

RESUMO

Myelin-associated glycoprotein (MAG) is a transmembrane glycoprotein concentrated in periaxonal Schwann cell and oligodendroglial membranes of myelin sheaths that serves as an antigen for immunoglobulin M (IgM) monoclonal antibodies. Individuals who harbor anti-MAG antibodies classically develop a progressive autoimmune peripheral neuropathy characterized clinically by ataxia, distal sensory loss, and gait instability, and electrophysiologically by distally accentuated conduction velocity slowing. Although off-label immunotherapy is common, there are currently no proven effective disease-modifying therapeutics, and most patients experience slow accumulation of disability over years and decades. The typically slowly progressive nature of this neuropathy presents unique challenges when trying to find effective anti-MAG therapeutic agents. Drug development has also been hampered by the lack of validated outcome measures that can detect clinically meaningful changes in a reasonable amount of time as well as by the lack of disease activity biomarkers. In this invited review, we provide an update on the state of clinicometric outcome measures and disease activity biomarkers in anti-MAG neuropathy. We highlight the insensitivity of widely used existing clinicometric outcome measures such as the Inflammatory Neuropathy Cause and Treatment (INCAT) disability score as well as the INCAT sensory subscore in anti-MAG neuropathy, referencing the two previous negative randomized controlled clinical trials evaluating rituximab. We then discuss newly emerging candidate therapeutic agents, including tyrosine kinase inhibitors and enhanced B-cell-depleting agents, among others. We conclude with a practical approach to the evaluation and management of anti-MAG neuropathy patients.


Assuntos
Neurite (Inflamação) , Doenças do Sistema Nervoso Periférico , Humanos , Glicoproteína Associada a Mielina , Doenças do Sistema Nervoso Periférico/terapia , Rituximab/uso terapêutico , Anticorpos Monoclonais , Imunoglobulina M , Autoanticorpos , Neurite (Inflamação)/tratamento farmacológico , Biomarcadores
13.
Eur J Neurol ; 30(2): 501-510, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35191144

RESUMO

BACKGROUND AND PURPOSE: A diagnostic score was developed to discriminate anti-myelin-associated-glycoprotein (MAG) neuropathy from chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and applied it to patients with atypical anti-MAG neuropathy. METHODS: The clinical and electrophysiological features of patients with a diagnosis of typical anti-MAG neuropathy were compared to those of patients with a diagnosis of CIDP. The association of each feature with the diagnosis was assessed in the two groups. Features showing a significant association with the diagnosis were included in a multivariable logistic regression model and adjusted odds ratios were estimated for each feature. A score ranging from 1 to 3 was applied to each feature based on the magnitude of the estimated odds ratios. The score was then applied to patients with a clinical diagnosis of CIDP who also had high anti-MAG antibody titers (CIDP-MAG). RESULTS: Thirty-one anti-MAG neuropathy patients, 45 typical CIDP patients and 16 CIDP-MAG patients were included. Scores in anti-MAG antibody patients ranged from 1 to 5 and in CIDP patients from -7 to -1. Using the score, 4/16 CIDP-MAG patients were diagnosed to have anti-MAG neuropathy and 12/16 patients to have CIDP. Response to intravenous immunoglobulin in the CIDP-MAG patients classified as CIDP was similar to that of definite CIDP patients and higher than that of anti-MAG neuropathy patients. CONCLUSIONS: Our score allowed an accurate discrimination to be made, amongst patients with anti-MAG antibodies, of those affected by CIDP and the patients with anti-MAG neuropathy. This score may help proper treatment to be chosen for patients with anti-MAG antibodies with a CIDP-like presentation.


Assuntos
Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Polirradiculoneuropatia , Humanos , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/terapia , Imunoglobulina M , Imunoglobulinas Intravenosas/uso terapêutico , Autoanticorpos , Glicoproteína Associada a Mielina , Polirradiculoneuropatia/tratamento farmacológico
14.
Environ Sci Technol ; 57(36): 13473-13486, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37639510

RESUMO

Dissimilatory arsenate-respiring prokaryotes (DARPs) are considered to be a key impetus of the reductive dissolution of solid-phase arsenic. However, little is known about the interaction between nitrate and DARPs so far. In this study, we showed that nitrate either inhibited or promoted the DARP population-catalyzed reductive mobilization of As in sediments. Metagenomic analysis of the microbial communities in the microcosms after seven days of As release assays suggested that microbes mainly consisted of: Type-I DARPs having potential to reduce NO3- into NO2- and Type-II DARPs having potential to reduce NO3- to NH4+. We further isolated two cultivable DARPs, Neobacillus sp. A01 and Paenibacillus sp. A02, which represent Type-I and -II DARPs, respectively. We observed that nitrate suppressed A01-mediated release of As(III) but promoted A02-mediated release of As(III). Furthermore, we demonstrated that this observation was due to the fact that nitrite, the end product of incomplete denitrification by Type-I DARPs, suppressed the arrA gene expression per cell and growth of all DARPs, whereas ammonium, the end product of dissimilatory nitrate reduction to ammonium (DNRA) by Type-II DARPs, enhanced the arrA gene expression per cell and significantly promoted the growth of all DARPs. These findings suggest that the actual effects of nitrate on DARP population-catalyzed reductive mobilization of arsenic, largely depend on the ratio of Type-I to Type-II DARPs in sediments.


Assuntos
Arsênio , Nitratos , Arseniatos , Nitritos
15.
J Peripher Nerv Syst ; 28(2): 269-275, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37041730

RESUMO

BACKGROUND: International consensus on IgM ± anti-MAG ± PNP (IgM PNP) is lacking. Despite increasing interest in clinical trials, validated disease-specific measures are needed to adequately capture limitations and changes over time. The IMAGiNe (IgM ± anti-myelin associated glycoprotein [MAG] peripheral neuropathy) study surges as an international collaboration to create a standardized registry of patients with IgM ± anti-MAG PNP. The consortium, which currently consists of 11 institutions from 7 countries, presents here the IMAGiNe study design and protocol. AIMS: Functional outcome measures will be constructed at the level of impairment, as well as activity and participation. We aim to describe the natural history of the cohort, the role of anti-MAG antibodies, the presence of clinical subtypes, and potential biomarkers. METHODS: The IMAGiNe study is a prospective, observational cohort study with a 3-year follow-up. At each assessment, researchers collect clinical data and subjects complete a list of preselected outcome measures. Among these, the "Pre-Rasch-built Overall Disability Scale (Pre-RODS)" questionnaire will be submitted to Rasch analysis to assess classic and modern clinimetric requirements. RESULTS: The final measures will include the IgM-PNP-specific RODS and Ataxia Rating Scale (IgM-PNP-ARS). Descriptions of the disease course, clinical heterogeneity, treatment regimes, variations in laboratory values, and antibody titers will help reach consensus on diagnosis and follow-up strategies. CONCLUSION: The constructed interval scales will be cross-culturally valid and suitable for use in future clinical trials and daily practice. The ultimate goals are to improve functional individualized assessment, reach international consensus, and lay the foundations for successful designs in future studies.


Assuntos
Doenças do Sistema Nervoso Periférico , Humanos , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/terapia , Imunoglobulina M , Glicoproteína Associada a Mielina , Biomarcadores , Autoanticorpos , Ataxia , Estudos Observacionais como Assunto
16.
J Stroke Cerebrovasc Dis ; 32(7): 107106, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37116446

RESUMO

OBJECTIVES: To delineate diurnal variation onset distinguishing ischemic from hemorrhagic stroke, wake from sleep onset, and weekdays from weekends/holidays. MATERIALS AND METHODS: We analyzed patients enrolled in the FAST-MAG trial of field-initiated neuroprotective agent in patients with hyperacute stroke within 2h of symptoms onset. Stroke onset times were analyzed in 1h, 4h, and 12h time blocks throughout the 24h day-night cycle. Patient demographic, clinical features, stroke severity, and prehospital workflow were evaluated for association with onset times. RESULTS: Among 1615 acute cerebrovascular disease patients, final diagnoses were acute cerebral ischemia in 76.5% and Intracerebral hemorrhage in 23.5%. Considering all acute cerebrovascular disease patients, frequency of wake onset times showed a bimodal pattern, with peaks on onsets at 09:00-13:59 and 17:00-18:59 and early morning (00:00-05:59) onset in only 3.8%. Circadian rhythmicity differed among stroke subtypes: in acute cerebral ischemia, a single broad plateau of elevated incidences was seen from 10:00-21:59; in Intracerebral hemorrhage, bimodal peaks occurred at 09:00 and 19:00. The ratio of Intracerebral hemorrhage to acute cerebral ischemia occurrence was highest in early morning, 02:00-06:59. Marked weekday vs weekends pattern variation was noted for acute cerebral ischemia, with a broad plateau between 09:00 and 21:59 on weekdays but a unimodal peak at 14:00-15:59 on weekends. CONCLUSIONS: Wake onset of acute cerebrovascular disease showed a marked circadian variation, with distinctive patterns of a broad elevated plateau among acute cerebral ischemia patients; a bimodal peak among intracerebral hemorrhage patients; and a weekend change in acute cerebral ischemia pattern to a unimodal peak.


Assuntos
Isquemia Encefálica , Transtornos Cerebrovasculares , Acidente Vascular Cerebral Hemorrágico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral Hemorrágico/diagnóstico , Acidente Vascular Cerebral Hemorrágico/complicações , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/complicações , Hemorragia Cerebral/epidemiologia , Transtornos Cerebrovasculares/etiologia
17.
J Biol Chem ; 296: 100779, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34000299

RESUMO

Calcium (Ca2+) is an essential mineral of endoplasmic reticulum (ER) luminal biochemistry because of the Ca2+ dependence of ER-resident chaperones charged with folding de novo proteins that transit this cellular compartment. ER Ca2+ depletion reduces the ability of chaperones to properly fold the proteins entering the ER, thus leading to an accumulation of misfolded proteins and the onset of a state known as ER stress. However, not all conditions that cause ER stress do so in a manner dependent on ER Ca2+ depletion. Agents such as tunicamycin inhibit the glycosylation of de novo polypeptides, a key step in the maturation process of newly synthesized proteins. Despite this established effect of tunicamycin, our understanding of how such conditions modulate ER Ca2+ levels is still limited. In the present study, we report that a variety of ER stress-inducing agents that have not been known to directly alter ER Ca2+ homeostasis can also cause a marked reduction in ER Ca2+ levels. Consistent with these observations, protecting against ER stress using small chemical chaperones, such as 4-phenylbutyrate and tauroursodeoxycholic acid, also attenuated ER Ca2+ depletion caused by these agents. We also describe a novel high-throughput and low-cost assay for the rapid quantification of ER stress using ER Ca2+ levels as a surrogate marker. This report builds on our understanding of ER Ca2+ levels in the context of ER stress and also provides the scientific community with a new, reliable tool to study this important cellular process in vitro.


Assuntos
Cálcio/metabolismo , Estresse do Retículo Endoplasmático , Cálcio/análise , Linhagem Celular , Retículo Endoplasmático/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Microscopia de Fluorescência , Resposta a Proteínas não Dobradas
18.
Prostate ; 82(1): 86-96, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34633090

RESUMO

BACKGROUND: Prostate-specific membrane antigen (PSMA)-targeted radioligand therapy (RLT) may be associated with renal toxicity. We aimed to identify predictive parameters for the development of chronic kidney disease (CKD) in patients with metastatic castration resistant prostate cancer (mCRPC) undergoing RLT. METHODS: In 46 mCRPC patients scheduled for Lu-177-PSMA-RLT, pretherapeutic estimated glomerular filtration rate (eGFR [ml/min/1.73 m2 ]), Tc-99m-mercaptoacetyltriglycine (Tc-99m-MAG3) clearance and baseline Ga-68-PSMA-ligand positron emission tomography (PET)-derived renal cortical uptake and PSMA-tumor volume (TV) were determined. We tested the predictive capability of these parameters and clinical risk factors for the occurrence of CKD (defined as CTCAE vers. 5.0 grade 2 or higher) during follow-up. RESULTS: After 4 ± 3 cycles of RLT average eGFR declined from 76 ± 17 to 72 ± 20 ml/min/1.73 m2 (p = 0.003). Increased estimated renal radiation dose (eRRD) was significantly associated with renal functional decline (p = 0.008). During follow-up, 16/46 (30.4%) developed CKD grade 2 (no grade 3 or higher). In receiver operating characteristic (ROC) analysis, pretherapeutic eGFR was highly accurate in identifying the occurrence of CKD vs no CKD with an area under the curve (AUC) of 0.945 (p < 0.001; best threshold, 77 ml/min/1.73 m2 ), followed by Tc-99m-MAG3-derived tubular extraction rate (TER; AUC, 0.831, p < 0.001; best threshold, 200 ml/min/1.73 m2 ). Renal PET signal (p = 0.751) and PSMA-TV (p = 0.942), however, were not predictive. Kaplan-Meier analyses revealed adverse renal outcome for patients with lower eGFR (p = 0.001) and lower scintigraphy-derived TER (p = 0.009), with pretherapeutic eGFR emerging as the sole predictive parameter in multivariate analysis (p = 0.007). CONCLUSION: Serious adverse renal events are not a frequent phenomenon after PSMA-targeted RLT. However, in patients developing moderate CKD after RLT, pretherapeutic eGFR is an independent predictor for renal impairment during follow-up.


Assuntos
Antígenos de Superfície , Glutamato Carboxipeptidase II , Lutécio , Neoplasias de Próstata Resistentes à Castração , Radioimunoterapia , Radioisótopos , Insuficiência Renal Crônica , Antígenos de Superfície/imunologia , Antígenos de Superfície/metabolismo , Taxa de Filtração Glomerular , Glutamato Carboxipeptidase II/imunologia , Glutamato Carboxipeptidase II/metabolismo , Humanos , Estimativa de Kaplan-Meier , Lutécio/administração & dosagem , Lutécio/efeitos adversos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/terapia , Radioimunoterapia/efeitos adversos , Radioimunoterapia/métodos , Radioisótopos/administração & dosagem , Radioisótopos/efeitos adversos , Eliminação Renal , Insuficiência Renal Crônica/induzido quimicamente , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/prevenção & controle , Risco Ajustado/métodos , Fatores de Risco , Tecnécio/farmacologia
19.
Br J Haematol ; 198(2): 298-306, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35420717

RESUMO

Monoclonal immunoglobulin M (IgM) anti-myelin-associated glycoprotein (MAG) neuropathy is a rare disabling condition, most commonly treated with rituximab monotherapy (R), which leads to neurological improvement in only 30%-50% of patients. The combination of rituximab plus chemotherapy has been proven to improve the level of responses. We studied the outcomes of anti-MAG neuropathy patients treated either by R, or by immunochemotherapy (ICT) in our centre, focusing on the incidence of the first neurological response evaluated by the modified Rankin scale (mRS). From 2011 to 2018, 64 patients were studied: 34 were treated with R and 30 with ICT. According to our treatment decision-making process, the median mRS was higher in the ICT group (mRS 2) than in the R group (mRS 1). At one year, improvements of the mRS rates were 46% and 18% in the ICT and R groups of patients respectively, with median times to response of eight and 13 months (p = 0.023). Adverse effects were higher in the ICT group: 62% vs 15% (p Ë‚ 0.01), all grades included. One secondary acute leukaemia occurred five years after treatment with ICT. In conclusion, ICT may be used as a valid option for patients with rapidly progressive and/or severe anti-MAG neuropathy symptoms.


Assuntos
Doenças do Sistema Nervoso Periférico , Autoanticorpos , Humanos , Imunoglobulina M , Imunoterapia/efeitos adversos , Paraproteínas , Doenças do Sistema Nervoso Periférico/terapia , Rituximab/efeitos adversos
20.
Muscle Nerve ; 65(6): 667-675, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35353922

RESUMO

INTRODUCTION/AIMS: Immunoglobulin M neuropathy associated with anti-myelin-associated glycoprotein antibody (IgM/anti-MAG) neuropathy typically presents with chronic, distal-dominant symmetrical sensory or sensorimotor deficits. Ultrasonographic studies of IgM/anti-MAG neuropathy are limited, and were all performed on Western populations. We aimed to characterize the nerve ultrasonographic features of IgM/anti-MAG neuropathy in the Japanese population and evaluate whether they differ from the findings of the common subtypes of chronic inflammatory demyelinating polyneuropathy (CIDP). METHODS: In this cross-sectional study, we retrospectively reviewed medical records and extracted the cross-sectional areas (CSAs) of C5-C7 cervical nerve roots and median and ulnar nerves of 6 IgM/anti-MAG neuropathy patients, 10 typical CIDP (t-CIDP) patients, 5 multifocal CIDP (m-CIDP) patients, and 17 healthy controls (HCs). RESULTS: Cervical nerve root CSAs were significantly larger at every examined site on both sides in IgM/anti-MAG neuropathy than in m-CIDP and HCs but were comparable to those in t-CIDP. Peripheral nerve enlargements were greatest at common entrapment sites (ie, wrist and elbow) in IgM/anti-MAG neuropathy, a pattern shared with t-CIDP but not with m-CIDP. The degree of nerve enlargement at entrapment sites compared to non-entrapment sites was significantly higher in IgM/anti-MAG neuropathy than in t-CIDP. DISCUSSION: Our study delineated the ultrasonographic features of IgM/anti-MAG neuropathy in the Japanese population and observed similar characteristics to those of t-CIDP, with subtle differences. Further studies comparing results from various populations are required to optimize the use of nerve ultrasound worldwide.


Assuntos
Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Autoanticorpos , Estudos Transversais , Humanos , Imunoglobulina M , Glicoproteína Associada a Mielina , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico por imagem , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA