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1.
Blood ; 143(18): 1807-1815, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38237147

RESUMO

ABSTRACT: Caplacizumab prevents the interaction between von Willebrand factor and platelets and is used to treat immune thrombotic thrombocytopenic purpura (iTTP). Its administration has been associated with a delay in ADAMTS13 activity restoration after plasma exchange (PEX) suspension. We analyzed the outcomes of 113 iTTP episodes, 75 of which were treated with caplacizumab, in 108 patients from the Spanish Registry of Thrombotic Thrombocytopenic Purpura. Caplacizumab shortened the time to platelet count normalization and reduced PEX requirement, exacerbations, and relapses. There was no difference in the time to achieve ADAMTS13 activity ≥20% after PEX end between caplacizumab-treated and nontreated episodes (median [interquartile range], 14.5 [7.7-27.2] vs 13.0 [8.0-29.0] days, P = .653). However, considering the 36 episodes in which caplacizumab was started ≤3 days after iTTP diagnosis, the time for ADAMTS13 restoration from PEX end was higher than in those episodes in which caplacizumab was started >3 days after iTTP diagnosis (20.0 [12.0-43.0] vs 11.0 [3.5-20.0] days, P = .003) or than in non-caplacizumab-treated episodes (P = .033). This finding could be related to a significantly shorter duration of PEX in early caplacizumab-treated episodes than in late caplacizumab-treated episodes (5.5 [4.0-9.0] vs 15.0 [11.0-21.5] days, P < .001) or non-caplacizumab-treated episodes (11.0 [6.0-26.0] days, P < .001). There were no differences in time to ADAMTS-13 restoration from PEX start (28.0 [17.2-47.5], 27.0 [19.0-37.5] and 29.5 [15.2-45.0] days in early caplacizumab-treated, late caplacizumab-treated and non-caplacizumab-treated episodes). Early administered caplacizumab does not prevent the requirement for immunosuppression but has beneficial effects by shortening PEX requirement without major safety concerns.


Assuntos
Proteína ADAMTS13 , Troca Plasmática , Púrpura Trombocitopênica Trombótica , Anticorpos de Domínio Único , Humanos , Proteína ADAMTS13/sangue , Proteína ADAMTS13/metabolismo , Púrpura Trombocitopênica Trombótica/tratamento farmacológico , Púrpura Trombocitopênica Trombótica/terapia , Masculino , Feminino , Anticorpos de Domínio Único/uso terapêutico , Adulto , Pessoa de Meia-Idade , Contagem de Plaquetas , Doença Aguda , Resultado do Tratamento , Idoso
2.
Chembiochem ; 25(6): e202300746, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38081789

RESUMO

A complex code of cellular signals is mediated by ubiquitin and ubiquitin-like (Ub/UbL) modifications on substrate proteins. The so-called Ubiquitin Code specifies protein fates, such as stability, subcellular localization, functional activation or suppression, and interactions. Hundreds of enzymes are involved in placing and removing Ub/UbL on thousands of substrates, while the consequences of modifications and the mechanisms of specificity are still poorly defined. Challenges include rapid and transient engagement of enzymes and Ub/UbL interactors, low stoichiometry of modified versus non-modified cellular substrates, and protease-mediated loss of Ub/UbL in lysates. To decipher this complexity and confront the challenges, many tools have been created to trap and identify substrates and interactors linked to Ub/UbL modification. This review focuses on an assortment of biotin-based tools developed for this purpose (for example BioUbLs, UbL-ID, BioE3, BioID), taking advantage of the strong affinity of biotin-streptavidin and the stringent lysis/washing approach allowed by it, paired with sensitive mass-spectrometry-based proteomic methods. Knowing how substrates change during development and disease, the consequences of substrate modification, and matching substrates to particular UbL-ligating enzymes will contribute new insights into how Ub/UbL signaling works and how it can be exploited for therapies.


Assuntos
Biotina , Ubiquitina , Ubiquitina/metabolismo , Proteômica , Peptídeo Hidrolases
3.
Periodontol 2000 ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38641954

RESUMO

This review focuses on three major aspects of oncoviruses' role in cancer development. To begin, we discuss their geographic distribution, revealing that seven oncoviruses cause 20% of all human cancers worldwide. Second, we investigate the primary carcinogenic mechanisms, looking at how these oncogenic viruses can induce cellular transformation, angiogenesis, and local and systemic inflammation. Finally, we investigate the possibility of SARS-CoV-2 infection reactivating latent oncoviruses, which could increase the risk of further disease. The development of oncovirus vaccines holds great promise for reducing cancer burden. Many unanswered questions about the host and environmental cofactors that contribute to cancer development and prevention remain, which ongoing research is attempting to address.

4.
Emerg Infect Dis ; 29(5): 992-996, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36821867

RESUMO

Heartland virus (HRTV) disease is an emerging tickborne illness in the midwestern and southern United States. We describe a reported fatal case of HRTV infection in the Maryland and Virginia region, states not widely recognized to have human HRTV disease cases. The range of HRTV could be expanding in the United States.


Assuntos
Infecções por Bunyaviridae , Phlebovirus , Viroses , Estados Unidos/epidemiologia , Humanos , Infecções por Bunyaviridae/diagnóstico , Phlebovirus/genética , Mid-Atlantic Region
5.
Adv Exp Med Biol ; 1404: 65-75, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36792871

RESUMO

In this chapter, we discuss motility control as a possible link between quorum sensing (QS) to surface attachment in Vibrio species. QS regulates a variety of behaviors that are important for the life cycle of many bacterial species, including virulence factor production, biofilm formation, or metabolic homeostasis. Therefore, without QS, many species of bacteria cannot survive in their natural environments. Here, we summarize several QS systems in different Vibrio species and discuss some of emerging features that suggest QS is intimately connected to motility control. Finally, we speculate the connection between motility and QS is critical for Vibrio species to detect solid surfaces for surface attachment.


Assuntos
Percepção de Quorum , Vibrio , Percepção de Quorum/fisiologia , Vibrio/genética , Vibrio/metabolismo , Fatores de Virulência , Biofilmes , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
6.
Alzheimers Dement ; 19(6): 2355-2364, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36464907

RESUMO

INTRODUCTION: Neurodegenerative disorders are associated with different pathologies that often co-occur but cannot be measured specifically with in vivo methods. METHODS: Thirty-three brain hemispheres from donors with an Alzheimer's disease (AD) spectrum diagnosis underwent T2-weighted magnetic resonance imaging (MRI). Gray matter thickness was paired with histopathology from the closest anatomic region in the contralateral hemisphere. RESULTS: Partial Spearman correlation of phosphorylated tau and cortical thickness with TAR DNA-binding protein 43 (TDP-43) and α-synuclein scores, age, sex, and postmortem interval as covariates showed significant relationships in entorhinal and primary visual cortices, temporal pole, and insular and posterior cingulate gyri. Linear models including Braak stages, TDP-43 and α-synuclein scores, age, sex, and postmortem interval showed significant correlation between Braak stage and thickness in the parahippocampal gyrus, entorhinal cortex, and Broadman area 35. CONCLUSION: We demonstrated an association of measures of AD pathology with tissue loss in several AD regions despite a limited range of pathology in these cases. HIGHLIGHTS: Neurodegenerative disorders are associated with co-occurring pathologies that cannot be measured specifically with in vivo methods. Identification of the topographic patterns of these pathologies in structural magnetic resonance imaging (MRI) may provide probabilistic biomarkers. We demonstrated the correlation of the specific patterns of tissue loss from ex vivo brain MRI with underlying pathologies detected in postmortem brain hemispheres in patients with Alzheimer's disease (AD) spectrum disorders. The results provide insight into the interpretation of in vivo structural MRI studies in patients with AD spectrum disorders.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Humanos , Doença de Alzheimer/metabolismo , alfa-Sinucleína/metabolismo , Proteínas tau/metabolismo , Doenças Neurodegenerativas/complicações , Imageamento por Ressonância Magnética , Proteínas de Ligação a DNA
7.
J Bacteriol ; 204(6): e0008922, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35638827

RESUMO

Bacillus subtilis exhibits swarming motility, a flagellar-mediated form of surface motility. Here, we use transposon mutagenesis and sequencing (TnSeq) to perform a high-throughput screen for candidate genes required for swarming. The TnSeq approach identified all of the known genes required for flagellar biosynthesis and nearly all of the previously reported regulators that promote swarming. Moreover, we identified an additional 36 genes that improve swarming and validated them individually. Among these, two mutants with severe defects were recovered, including fliT, required for flagellar biosynthesis, and a gene of unknown function, yolB, whose defect could not be attributed to a lack of flagella. In addition to discovering additional genes required for B. subtilis swarming, our work validates TnSeq as a powerful approach for comprehensively identifying genes important for nonessential processes such as colony expansion on plates. IMPORTANCE In TnSeq, transposons are randomly inserted throughout the chromosome at a population level, but insertions that disrupt genes of essential function cause strains that carry them to fall out of the population and appear underrepresented at the sequence level. Here, we apply TnSeq to the nonessential phenotype of motility in B. subtilis and spatially select for cells proficient in swarming. We find that insertions in nearly all genes previously identified as required for swarming are underrepresented in TnSeq analysis, and we identify 36 additional genes that enhance swarming. We demonstrate that TnSeq is a powerful tool for the genetic analysis of motility and likely other nonlethal screens for which enrichment is strong.


Assuntos
Bacillus subtilis , Proteínas de Bactérias , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Flagelos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutagênese , Mutagênese Insercional , Mutação
8.
Lab Invest ; 102(4): 401-410, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34893758

RESUMO

The oncoprotein Smoothened (SMO), a Frizzled-class-G-protein-coupled receptor, is the central transducer of hedgehog (Hh) signaling. While canonical SMO signaling is best understood in the context of cilia, evidence suggests that SMO has other functions in cancer biology that are unrelated to canonical Hh signaling. Herein, we provided evidence that elevated levels of human SMO show a strong correlation with elevated levels of insulin-like growth factor 1 receptor (IGF1R) and reduced survival in diffuse large B-cell lymphoma (DLBCL). As an integral component of raft microdomains, SMO plays a fundamental role in maintaining the levels of IGF1R in lymphoma and breast cancer cells as well IGF1R-associated activation of protein kinase B (AKT). Silencing of SMO increases lysosomal degradation and favors a localization of IGF1R to late endosomal compartments instead of early endosomal compartments from which much of the receptor would normally recycle. In addition, loss of SMO interferes with the lipid raft localization and retention of the remaining IGF1R and AKT, thereby disrupting the primary signaling context for IGF1R/AKT. This activity of SMO is independent of its canonical signaling and represents a novel and clinically relevant contribution to signaling by the highly oncogenic IGF1R/AKT signaling axis.


Assuntos
Fator de Crescimento Insulin-Like I , Proteínas Proto-Oncogênicas c-akt , Proteínas Hedgehog/metabolismo , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/fisiologia , Receptor Smoothened/metabolismo
9.
Brain ; 144(9): 2784-2797, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34259858

RESUMO

Tau protein neurofibrillary tangles are closely linked to neuronal/synaptic loss and cognitive decline in Alzheimer's disease and related dementias. Our knowledge of the pattern of neurofibrillary tangle progression in the human brain, critical to the development of imaging biomarkers and interpretation of in vivo imaging studies in Alzheimer's disease, is based on conventional two-dimensional histology studies that only sample the brain sparsely. To address this limitation, ex vivo MRI and dense serial histological imaging in 18 human medial temporal lobe specimens (age 75.3 ± 11.4 years, range 45 to 93) were used to construct three-dimensional quantitative maps of neurofibrillary tangle burden in the medial temporal lobe at individual and group levels. Group-level maps were obtained in the space of an in vivo brain template, and neurofibrillary tangles were measured in specific anatomical regions defined in this template. Three-dimensional maps of neurofibrillary tangle burden revealed significant variation along the anterior-posterior axis. While early neurofibrillary tangle pathology is thought to be confined to the transentorhinal region, we found similar levels of burden in this region and other medial temporal lobe subregions, including amygdala, temporopolar cortex, and subiculum/cornu ammonis 1 hippocampal subfields. Overall, the three-dimensional maps of neurofibrillary tangle burden presented here provide more complete information about the distribution of this neurodegenerative pathology in the region of the cortex where it first emerges in Alzheimer's disease, and may help inform the field about the patterns of pathology spread, as well as support development and validation of neuroimaging biomarkers.


Assuntos
Mapeamento Encefálico/métodos , Imageamento Tridimensional/métodos , Emaranhados Neurofibrilares/patologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/patologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
10.
Eur J Pediatr ; 181(6): 2283-2290, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35212827

RESUMO

Upper extremity involvement is one of the most common motor impairments in children with unilateral spastic cerebral palsy (CP). One tool for the assessment of manual function in CP is the Nine Hole Peg Test (NHPT). However, the reliability of the NHPT in patients with unilateral CP is unknown. This study aimed to analyze the intra-rater inter-session reliability of the NHPT in unilateral spastic CP, for its use in clinical practice and research. A total of 27 participants with spastic unilateral CP were included. Reliability was verified by the intraclass correlation coefficient (ICC), standard error of measurement, and minimum detectable change. The agreement was analyzed by the Bland-Altman method. An excellent intra-rater reliability was observed for the non-affected side (ICC = 0.94) and the affected side (ICC = 0.96). The minimal detectable change was 4 and 12 s for the non-affected and affected side, respectively. There were no significant biases between repetitions.   Conclusions: The NHPT showed excellent intra-rater inter-session reliability in patients with spastic unilateral CP. In addition, the test shows adequate agreement and proportionally small errors to assess manual dexterity. What is Known: • The Nine Hole Peg Test (NHPT) is widely used to assess dexterity in patients with neurological conditions. • The NHPT has demonstrated appropriate measurement properties in healthy children and adults with neurological conditions. What is New: • The NHPT presents excellent reliability, small measurement errors, and adequate agreement for the assessment of patients with cerebral palsy. • The measurement error of the NHPT in unilateral cerebral palsy may be up to 13% of the total time to perform it.


Assuntos
Paralisia Cerebral , Adulto , Paralisia Cerebral/complicações , Paralisia Cerebral/diagnóstico , Criança , Humanos , Espasticidade Muscular , Reprodutibilidade dos Testes
11.
Aesthetic Plast Surg ; 46(5): 2438-2449, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35648192

RESUMO

OBJECTIVE: To assess the efficacy and safety of a new non-invasive body contouring device in patients with localized fat in abdomen or in abdomen and hips. Additionally, we also evaluated the patient satisfaction with the procedure. METHODS: Prospective and non-randomized open label study. The patients underwent four sessions, separated by 1 week each, with the Alma PrimeX, a non-invasive body contouring device that combines pulsed non-focus ultrasound and a Unipolar radiofrequency. The primary end point was the mean change in fat tissue thickness, assessed by diagnostic ultrasound, from baseline to 3-months after the last treatment-session. RESULTS: Fifteen subjects were evaluated. As compared to pre-treatment thickness, Hodges-Lehmann median difference (95% CI) was - 85.3 (- 107.5 to - 62.0) mm, p = 0.0001; - 70.3 (- 95.0 to - 48.5) mm, p = 0.0001; - 100.0 (- 140.5 to - 49.5) mm, p = 0.0039; and - 71.8 (- 132.5 to - 23.0) mm, p = 0.0078 in infraumbilical, supraumbilical, right hip, and left hip, respectively. Pretreatment fat volume was significantly reduced from 32.9% to 31.2%, p = 0.0006. The median (interquartile range) degree of patient satisfaction was 4.0 (1.0-5.0), with 13 (86.7%) patients being "Highly satisfied" or "Satisfied" with the treatment results. The most common adverse event was discomfort, followed by erythema. All the adverse events were mild and were successfully resolved without treatment. CONCLUSIONS: Combine therapy of a Pulsed non-focus ultrasound and Unipolar radiofrequency using the non-invasive device Alma PrimeX was an effective and safe treatment for reducing fat tissue thickness in abdomen and hips in patients with localized fat. Patients' satisfaction with the procedure was high. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Contorno Corporal , Humanos , Contorno Corporal/métodos , Estudos Prospectivos , Projetos Piloto , Resultado do Tratamento , Ondas Ultrassônicas
12.
Int J Mol Sci ; 23(3)2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35163721

RESUMO

The use of surfactants in polymerization reactions is particularly important, mainly in emulsion polymerizations. Further, micelles from biocompatible surfactants find use in pharmaceutical dosage forms. This paper reviews recent developments in the synthesis of novel gemini and bicephalous surfactants, micelle formation, and their applications in polymer and nanoparticle synthesis, oil recovery, catalysis, corrosion, protein binding, and biomedical area, particularly in drug delivery.


Assuntos
Micelas , Tensoativos , Polimerização , Polímeros
13.
Int J Mol Sci ; 23(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36555465

RESUMO

Antimicrobial resistance (AMR) is a serious public health problem that results in high morbidity and mortality rates. In particular, multidrug-resistant (MDR) strains circulating in hospital settings pose a major threat as they are associated with serious nosocomial infections. Therefore, regular cleaning and disinfection procedures, usually using chemical disinfectants, must be implemented in these facilities. Hydrogen peroxide (HP)-based disinfectants have proven high microbicidal activity and several comparative advantages over conventional disinfectants. We assessed the in vitro biocidal activity of an 8% HP solution combined with 30 mg/L silver ions (HP + Ag) against MDR clinical isolates of Klebsiella pneumoniae (MDRKp) and Pseudomonas aeruginosa (MDRPa), and methicillin-resistant Staphylococcus aureus (MRSA). Accordingly, the in vitro antibacterial activity was determined using the macrodilution method, and the efficacy was determined for 30 min in terms of (1) activity on bacteria in suspension and (2) activity on surfaces using vaporized HP + Ag on a 20 cm2 stainless steel surface. A strong bactericidal effect of HP + Ag was observed against MDRKp, MDRPa, and MRSA strains, with minimum inhibitory concentrations and minimum bactericidal concentrations between 362.5 and 5800 mg/L. A strong effect was observed during the 30 min of HP + Ag exposure to the resistant clinical isolates, with over 4-Log10 reduction in CFUs. Regarding the efficacy of the disinfectant on surfaces, bacterial load reductions of >99% were observed. These results suggest that HP + Ag is potentially useful as an effective disinfectant for decontaminating surfaces in hospital settings suspected of contamination with MDR bacteria.


Assuntos
Desinfetantes , Staphylococcus aureus Resistente à Meticilina , Peróxido de Hidrogênio/farmacologia , Prata/farmacologia , Desinfetantes/farmacologia , Desinfecção/métodos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
14.
Adv Skin Wound Care ; 35(12): 675-679, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36179316

RESUMO

OBJECTIVE: To determine if health education has an influence on podiatric knowledge, self-care, and conditions in adults with diabetes mellitus. DATA SOURCES: The authors conducted a literature search for Spanish-, English-, and Portuguese-language publications using PubMed, Scopus, Dialnet, and CUIDEN. STUDY SELECTION: Selected keywords related to diabetes, health education, (diabetic) foot, and self-care were searched, and the titles, abstracts, and relevant full-text articles were screened. Thirteen studies were selected with a total of 1,296 participants. Four were randomized controlled trials, and nine were quasi-experimental studies. DATA EXTRACTION: Data pertaining to preventive intervention and study outcomes were extracted. DATA SYNTHESIS: The preventive interventions used varied from traditional educational workshops and one-on-one patient education to new technological strategies. Three different outcomes were evaluated in each study: podiatric knowledge (n = 4), foot self-care (n = 13), and foot problems (n = 2). CONCLUSIONS: Health education interventions increase podiatric self-care in adults with diabetes mellitus. These interventions appear to contribute positively to foot health and podiatric knowledge.


Assuntos
Diabetes Mellitus , Podiatria , Adulto , Humanos , Autocuidado , Diabetes Mellitus/terapia , Educação em Saúde
15.
J Bacteriol ; 203(10)2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33649146

RESUMO

Lytic enzymes play an essential role in the remodeling of bacterial peptidoglycan (PG), an extracellular mesh-like structure that retains the membrane in the context of high internal osmotic pressure. Peptidoglycan must be unfailingly stable to preserve cell integrity, but must also be dynamically remodeled for the cell to grow, divide, and insert macromolecular machines. The flagellum is one such macromolecular machine that transits the PG, and flagellar insertion is aided by localized activity of a dedicated PG lyase in Gram-negative bacteria. To date, there is no known dedicated lyase in Gram-positive bacteria for the insertion of flagella. Here, we take a reverse-genetic candidate-gene approach and find that cells mutated for the lytic transglycosylase CwlQ exhibit a severe defect in flagellum-dependent swarming motility. We further show that CwlQ is expressed by the motility sigma factor SigD and is secreted by the type III secretion system housed inside the flagellum. Nonetheless, cells with mutations of CwlQ remain proficient for flagellar biosynthesis even when mutated in combination with four other lyases related to motility (LytC, LytD, LytF, and CwlO). The PG lyase (or lyases) essential for flagellar synthesis in B. subtilis, if any, remains unknown.IMPORTANCE Bacteria are surrounded by a wall of peptidoglycan and early work in Bacillus subtilis was the first to suggest that bacteria needed to enzymatically remodel the wall to permit insertion of the flagellum. No PG remodeling enzyme alone or in combination, however, has been found to be essential for flagellar assembly in B. subtilis Here, we take a reverse-genetic candidate-gene approach and find that the PG lytic transglycosylase CwlQ is required for swarming motility. Subsequent characterization determined that while CwlQ was coexpressed with motility genes and is secreted by the flagellar secretion apparatus, it was not required for flagellar synthesis. The PG lyase needed for flagellar assembly in B. subtilis remains unknown.


Assuntos
Bacillus subtilis/enzimologia , Bacillus subtilis/fisiologia , Flagelos/metabolismo , Peptidoglicano Glicosiltransferase/metabolismo , Peptidoglicano/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/ultraestrutura , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Movimento , Mutação , Peptidoglicano Glicosiltransferase/genética , Fator sigma/metabolismo , Sistemas de Secreção Tipo III/metabolismo
16.
J Bacteriol ; 203(17): e0022721, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34124944

RESUMO

Swarming motility is flagellum-mediated movement over a solid surface, and Bacillus subtilis cells require an increase in flagellar density to swarm. SwrB is a protein of unknown function required for swarming that is necessary to increase the number of flagellar hooks but not basal bodies. Previous work suggested that SwrB activates flagellar type III secretion, but the mechanism by which it might perform this function is unknown. Here, we show that SwrB likely acts substoichiometrically as it localizes as puncta at the membrane in numbers fewer than those of flagellar basal bodies. Moreover, the action of SwrB is likely transient as puncta of SwrB were not dependent on the presence of the basal bodies and rarely colocalized with flagellar hooks. Random mutagenesis of the SwrB sequence found that a histidine within the transmembrane segment was conditionally required for activity and punctate localization. Finally, three hydrophobic residues that precede a cytoplasmic domain of poor conservation abolished SwrB activity when mutated and caused aberrant migration during electrophoresis. Our data are consistent with a model in which SwrB interacts with the flagellum, changes conformation to activate type III secretion, and departs. IMPORTANCE Type III secretion systems (T3SSs) are elaborate nanomachines that form the core of the bacterial flagellum and injectisome of pathogens. The machines not only secrete proteins like virulence factors but also secrete the structural components for their own assembly. Moreover, proper construction requires complex regulation to ensure that the parts are roughly secreted in the order in which they are assembled. Here, we explore a poorly understood activator of the flagellar T3SS activation in Bacillus subtilis called SwrB. To aid mechanistic understanding, we determine the rules for subcellular punctate localization, the topology with respect to the membrane, and critical residues required for SwrB function.


Assuntos
Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Bacillus subtilis/química , Bacillus subtilis/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Flagelos/química , Flagelos/genética , Flagelos/metabolismo , Regulação Bacteriana da Expressão Gênica , Domínios Proteicos , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo III/metabolismo
17.
Carcinogenesis ; 42(5): 714-723, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33421057

RESUMO

Melanoma is one of the most aggressive forms of human cancer and its incidence has significantly increased worldwide over the last decades. This neoplasia has been characterized by the release of a wide variety of soluble factors, which could stimulate tumor cell proliferation and survival in an autocrine and paracrine manner. Consequently, we sought to evaluate the pattern of soluble factors produced by pre-metastatic and metastatic melanoma established cultures, and to determine whether these factors can be detected in the autologous serum of malignant melanoma patients. Our results showed that both melanoma cultures had a common profile of 27 soluble factors mainly characterized by the high expression of VEGF-A, IL-6, MCP-1, IL-8, and SDF-1. In addition, when we compared supernatants, we observed significant differences in VEGF-A, BDNF, FGF-2, and NGF-ß concentrations. As we found in melanoma cultures, serum samples also had their specific production pattern composed by 21 soluble factors. Surprisingly, PDGF-BB and EGF were only found in serum, whereas IL-2, IL-4, IL-8, IL31, FGF2, and GRO-α were only expressed in the supernatant. Significant differences in PDGF-BB, MIP-1ß, HGF, PIGF-1, BDNF, EGF, Eotaxin, and IP-10 were also found after comparing autologous serum with healthy controls. According to this, no correlation was found between culture supernatants and autologous serum samples, which suggests that some factors may act locally, and others systemically. Nonetheless, after validation of our results in an independent cohort of patients, we concluded that PDGF-BB, VEGF-A, and IP-10 serum levels could be used to monitor different melanoma stages.


Assuntos
Becaplermina/sangue , Quimiocina CXCL10/sangue , Melanoma/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Comunicação Autócrina/genética , Becaplermina/genética , Proliferação de Células/genética , Quimiocina CCL2/sangue , Quimiocina CXCL10/genética , Quimiocina CXCL12/sangue , Citocinas/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Interleucina-6/sangue , Interleucina-8/sangue , Masculino , Melanoma/genética , Melanoma/patologia , Proteínas de Neoplasias/sangue , Proteínas de Neoplasias/genética , Comunicação Parácrina/genética , Fator A de Crescimento do Endotélio Vascular/genética
18.
J Anat ; 239(4): 856-868, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34028021

RESUMO

The perinatal period, sensitive for newborn survival, is also one of the most critical moments in human brain development. Perinatal hypoxia due to reduced blood supply to the brain (ischemia) is one of the main causes of neonatal mortality. Brain damage caused by perinatal hypoxia-ischemia (HI) can lead to neuro- and psychological disorders. However, its impact seems to be region-dependent, with the hippocampus being one of the most affected areas. Among the neuronal populations of the hippocampus, some interneuron groups - such as somatostatin- or neuropeptide Y-expressing neurons - seem to be particularly vulnerable. The limited information available about the effects of HI in the hippocampus comes mainly from animal models and adult human studies. This article presents an immunohistochemical analysis of somatostatin (SOM) and neuropeptide Y (NPY) expression in the developing human hippocampus after perinatal HI. Two rostrocaudal sections of the body of the hippocampus were analysed, and the number of immunostained cells in the polymorphic layer of the dentate gyrus (DG) and the pyramidal cell layer and stratum oriens of the CA3, CA2 and CA1 fields of the hippocampus proper were quantified. The results showed a lower density of both neuropeptides in hypoxic compared to control cases. In the HI group, the number of SOM-immunoreactive cell bodies was statistically significantly lower in the pyramidal cell layer and stratum oriens of CA1, while the number of NPY-expressing neurons was statistically lower in the pyramidal cell layer of CA2. Besides, the number of SOM-expressing neurons was significantly higher in the stratum oriens of CA1 compared to that in CA2. In sum, we observed a different vulnerability of SOM- and NPY-containing neurons in the developing human hippocampus following perinatal HI damage. Our results could contribute to a better understanding of the behaviour of these neuronal populations under stressful conditions during the perinatal period.


Assuntos
Hipocampo , Neuropeptídeo Y , Animais , Hipocampo/metabolismo , Humanos , Hipóxia , Isquemia , Neurônios/metabolismo
19.
Metabolomics ; 17(7): 66, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34228201

RESUMO

INTRODUCTION: In humans and companion animals, obesity is accompanied by metabolic derangements. Studies have revealed differences in the composition of the fecal microbiome between obese dogs and those with an ideal body weight. OBJECTIVES: We have previously reported that the fecal microbiome in obese dogs changes after controlled weight reduction, induced by feeding a diet high in fiber and protein. Despite these findings, it is unclear if taxonomic differences infer differences at the functional level between obese dogs and those with an ideal body weight. METHODOLOGY: Untargeted fecal metabolome analysis was performed on dogs with obesity before and after weight loss achieved by feeding a high-fiber-high-protein diet. RESULTS: Fecal metabolome analysis revealed a total of 13 compounds that changed in concentration in obese dogs after weight loss. Of these compounds, metabolites associated with bacterial metabolism decreased after weight loss including purine, L-(-)-methionine, coumestrol, and the alkaloids 1-methylxanthine and trigonelline. Conversely, the polyphenols (-)-epicatechin and matairesinol and the quinoline derivatives 1,5-isoquinolinediol and 2-hydroxiquinoline increased after weight loss. CONCLUSION: These results suggest differences in intestinal microbiome at the functional level after weight loss, but further studies are needed to determine the role of these compounds in the etiology of obesity and weight loss.


Assuntos
Dieta Rica em Proteínas , Microbioma Gastrointestinal , Animais , Fibras na Dieta , Cães , Metaboloma , Obesidade/dietoterapia , Redução de Peso
20.
Transfus Med Hemother ; 48(4): 234-239, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34539317

RESUMO

Therapeutic apheresis (TA) is prescribed to patients that suffer from a severe progressive disease that is not sufficiently treated by conventional medications. A way to gain more knowledge about this treatment is usually by the local analysis of data. However, the use of large quality assessment registries enables analyses of even rare findings. Here, we report some of the recent data from the World Apheresis Association (WAA) registry. Data from >104,000 procedures were documented, and TA was performed on >15,000 patients. The main indication for TA was the collection of autologous stem cells (45% of patients) as part of therapy for therapy. Collection of stem cells from donors for allogeneic transplantation was performed in 11% of patients. Patients with indications such as neurological diseases underwent plasma exchange (28%). Extracorporeal photochemotherapy, lipid apheresis, and antibody removal were other indications. Side effects recorded in the registry have decreased significantly over the years, with approximately only 10/10,000 procedures being interrupted for medical reasons. CONCLUSION: Collection of data from TA procedures within a multinational and multicenter concept facilitates the improvement of treatment by enabling the analysis of and feedback on indications, procedures, effects, and side effects.

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