Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 334
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
J Gen Virol ; 105(8)2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39163114

RESUMO

Equine rotavirus species A (ERVA) G3P[12] and G14P[12] are two dominant genotypes that cause foal diarrhoea with a significant economic impact on the global equine industry. ERVA can also serve as a source of novel (equine-like) rotavirus species A (RVA) reassortants with zoonotic potential as those identified previously in 2013-2019 when equine G3-like RVA was responsible for worldwide outbreaks of severe gastroenteritis and hospitalizations in children. One hurdle to ERVA research is that the standard cell culture system optimized for human rotavirus replication is not efficient for isolating ERVA. Here, using an engineered cell line defective in antiviral innate immunity, we showed that both equine G3P[12] and G14P[12] strains can be rapidly isolated from diarrhoeic foals. The genome sequence analysis revealed that both G3P[12] and G14P[12] strains share the identical genotypic constellation except for VP7 and VP6 segments in which G3P[12] possessed VP7 of genotype G3 and VP6 of genotype I6 and G14P[12] had the combination of VP7 of genotype G14 and VP6 of genotype I2. Further characterization demonstrated that two ERVA genotypes have a limited cross-neutralization. The lack of an in vitro broad cross-protection between both genotypes supported the increased recent diarrhoea outbreaks due to equine G14P[12] in foals born to dams immunized with the inactivated monovalent equine G3P[12] vaccine. Finally, using the structural modelling approach, we provided the genetic basis of the antigenic divergence between ERVA G3P[12] and G14P[12] strains. The results of this study will provide a framework for further investigation of infection biology, pathogenesis and cross-protection of equine rotaviruses.


Assuntos
Antígenos Virais , Diarreia , Genótipo , Doenças dos Cavalos , Infecções por Rotavirus , Rotavirus , Animais , Cavalos , Rotavirus/genética , Rotavirus/imunologia , Rotavirus/isolamento & purificação , Rotavirus/classificação , Infecções por Rotavirus/veterinária , Infecções por Rotavirus/virologia , Infecções por Rotavirus/imunologia , Doenças dos Cavalos/virologia , Doenças dos Cavalos/imunologia , Diarreia/virologia , Diarreia/veterinária , Antígenos Virais/genética , Antígenos Virais/imunologia , Genoma Viral/genética , Filogenia , Linhagem Celular
2.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34475219

RESUMO

Group A rotaviruses cause severe gastroenteritis in infants and young children worldwide, with P[II] genogroup rotaviruses (RVs) responsible for >90% of global cases. RVs have diverse host ranges in different human and animal populations determined by host histo-blood group antigen (HBGA) receptor polymorphism, but details governing diversity, host ranges, and species barriers remain elusive. In this study, crystal structures of complexes of the major P[II] genogroup P[4] and P[8] genotype RV VP8* receptor-binding domains together with Lewis epitope-containing LNDFH I glycans in combination with VP8* receptor-glycan ligand affinity measurements based on NMR titration experiments revealed the structural basis for RV genotype-specific switching between ßß and ßα HBGA receptor-binding sites that determine RV host ranges. The data support the hypothesis that P[II] RV evolution progressed from animals to humans under the selection of type 1 HBGAs guided by stepwise host synthesis of type 1 ABH and Lewis HBGAs. The results help explain disease burden, species barriers, epidemiology, and limited efficacy of current RV vaccines in developing countries. The structural data has the potential to impact the design of future vaccine strategies against RV gastroenteritis.


Assuntos
Antígenos de Grupos Sanguíneos/imunologia , Evolução Molecular , Rotavirus/genética , Cristalografia por Raios X , Especificidade de Hospedeiro/genética , Humanos , Ressonância Magnética Nuclear Biomolecular/métodos , Conformação Proteica , Rotavirus/química , Rotavirus/imunologia , Proteínas não Estruturais Virais/química , Vacinas Virais/imunologia
3.
Metabolomics ; 19(7): 64, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37378680

RESUMO

INTRODUCTION: Interpretation and analysis of NMR-based metabolic profiling studies is limited by substantially incomplete commercial and academic databases. Statistical significance tests, including p-values, VIP scores, AUC values and FC values, can be largely inconsistent. Data normalization prior to statistical analysis can cause erroneous outcomes. OBJECTIVES: The objectives were (1) to quantitatively assess consistency among p-values, VIP scores, AUC values and FC values in representative NMR-based metabolic profiling datasets, (2) to assess how data normalization can impact statistical significance outcomes, (3) to determine resonance peak assignment completion potential using commonly used databases and (4) to analyze intersection and uniqueness of metabolite space in these databases. METHODS: P-values, VIP scores, AUC values and FC values, and their dependence on data normalization, were determined in orthotopic mouse model of pancreatic cancer and two human pancreatic cancer cell lines. Completeness of resonance assignments were evaluated using Chenomx, the human metabolite database (HMDB) and the COLMAR database. The intersection and uniqueness of the databases was quantified. RESULTS: P-values and AUC values were strongly correlated compared to VIP or FC values. Distributions of statistically significant bins depended strongly on whether or not datasets were normalized. 40-45% of peaks had either no or ambiguous database matches. 9-22% of metabolites were unique to each database. CONCLUSIONS: Lack of consistency in statistical analyses of metabolomics data can lead to misleading or inconsistent interpretation. Data normalization can have large effects on statistical analysis and should be justified. About 40% of peak assignments remain ambiguous or impossible with current databases. 1D and 2D databases should be made consistent to maximize metabolite assignment confidence and validation.


Assuntos
Imageamento por Ressonância Magnética , Metabolômica , Animais , Camundongos , Humanos , Espectroscopia de Ressonância Magnética , Bases de Dados Factuais , Linhagem Celular
4.
Mol Ther ; 30(10): 3270-3283, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-35619558

RESUMO

Profound natural killer (NK) cell suppression after cancer surgery is a main driver of metastases and recurrence, for which there is no clinically approved intervention available. Surgical stress is known to cause systemic postoperative changes that negatively modulate NK cell function including the expansion of surgery-induced myeloid-derived suppressor cells (Sx-MDSCs) and a marked reduction in arginine bioavailability. In this study, we determine that Sx-MDSCs regulate systemic arginine levels in the postoperative period and that restoring arginine imbalance after surgery by dietary intake alone was sufficient to significantly reduce surgery-induced metastases in our preclinical murine models. Importantly, the effects of perioperative arginine were dependent upon NK cells. Although perioperative arginine did not prevent immediate NK cell immunoparalysis after surgery, it did accelerate their return to preoperative cytotoxicity, interferon gamma secretion, and activating receptor expression. Finally, in a cohort of patients with colorectal cancer, postoperative arginine levels were shown to correlate with their Sx-MDSC levels. Therefore, this study lends further support for the use of perioperative arginine supplementation by improving NK cell recovery after surgery.


Assuntos
Arginina , Células Supressoras Mieloides , Animais , Humanos , Interferon gama/metabolismo , Células Matadoras Naturais/metabolismo , Camundongos
5.
J Strength Cond Res ; 37(10): 2016-2022, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37729514

RESUMO

ABSTRACT: Faulhaber, M, Schneider, S, Rausch, LK, Dünnwald, T, Menz, V, Gatterer, H, Kennedy, MD, and Schobersberger, W. Repeated short-term bouts of hyperoxia improve aerobic performance in acute hypoxia. J Strength Cond Res 37(10): 2016-2022, 2023-This study aimed to test the effects of repeated short-term bouts of hyperoxia on maximal 5-minute cycling performance under acute hypoxic conditions (3,200 m). Seventeen healthy and recreationally trained individuals (7 women and 10 men) participated in this randomized placebo-controlled cross-over trial. The procedures included a maximal cycle ergometer test and 3 maximal 5-minute cycling time trials (TTs). TT1 took place in normoxia and served for habituation and reference. TT2 and TT3 were conducted in normobaric hypoxia (15.0% inspiratory fraction of oxygen). During TT2 and TT3, the subjects were breathing through a face mask during five 15-second periods. The face mask was connected through a nonrebreathing T valve to a 300-L bag filled with 100% oxygen (intermittent hyperoxia) or ambient hypoxic air (placebo). The main outcome was the mean power output during the TT. Statistical significance level was set at p < 0.05. The mean power output was higher in the intermittent hyperoxia compared with the placebo condition (255.5 ± 49.6 W vs. 247.4 ± 48.2 W, p = 0.001). Blood lactate concentration and ratings of perceived exertion were significantly lower by about 9.7 and 7.3%, respectively, in the intermittent hyperoxia compared with the placebo condition, whereas heart rate values were unchanged. IH application increased arterial oxygen saturation (82.9 ± 2.6% to 92.4 ± 3.3%, p < 0.001). Repeated 15-second bouts of hyperoxia, applied during high-intensity exercise in hypoxia, are sufficient to increase power output. Future studies should focus on potential dose-response effects and the involved mechanisms.


Assuntos
Hiperóxia , Masculino , Feminino , Humanos , Hipóxia , Oxigênio , Ciclismo , Ácido Láctico
6.
Proteins ; 90(1): 110-122, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34322903

RESUMO

Protein ß-turn classification remains an area of ongoing development in structural biology research. While the commonly used nomenclature defining type I, type II and type IV ß-turns was introduced in the 1970s and 1980s, refinements of ß-turn type definitions have been introduced as recently as 2019 by Dunbrack, Jr and co-workers who expanded the number of ß-turn types to 18 (Shapovalov et al, PLOS Computat. Biol., 15, e1006844, 2019). Based on their analysis of 13 030 turns from 1074 ultrahigh resolution (≤1.2 Å) protein structures, they used a new clustering algorithm to expand the definitions used to classify protein ß-turns and introduced a new nomenclature system. We recently encountered a specific problem when classifying ß-turns in crystal structures of pentapeptide repeat proteins (PRPs) determined in our lab that are largely composed of ß-turns that often lie close to, but just outside of, canonical ß-turn regions. To address this problem, we devised a new scheme that merges the Klyne-Prelog stereochemistry nomenclature and definitions with the Ramachandran plot. The resulting Klyne-Prelog-modified Ramachandran plot scheme defines 1296 distinct potential ß-turn classifications that cover all possible protein ß-turn space with a nomenclature that indicates the stereochemistry of i + 1 and i + 2 backbone dihedral angles. The utility of the new classification scheme was illustrated by re-classification of the ß-turns in all known protein structures in the PRP superfamily and further assessed using a database of 16 657 high-resolution protein structures (≤1.5 Å) from which 522 776 ß-turns were identified and classified.


Assuntos
Conformação Proteica , Proteínas , Algoritmos , Sequência de Aminoácidos , Análise por Conglomerados , Cristalografia , Ligação de Hidrogênio , Modelos Moleculares , Proteínas/química , Proteínas/classificação , Proteínas/metabolismo , Estereoisomerismo
7.
Eur Respir J ; 60(6)2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35680144

RESUMO

BACKGROUND: Signalling through platelet-derived growth factor receptor (PDGFR), colony-stimulating factor 1 receptor (CSF1R) and mast/stem cell growth factor receptor kit (c-KIT) plays a critical role in pulmonary arterial hypertension (PAH). We examined the preclinical efficacy of inhaled seralutinib, a unique small-molecule PDGFR/CSF1R/c-KIT kinase inhibitor in clinical development for PAH, in comparison to a proof-of-concept kinase inhibitor, imatinib. METHODS: Seralutinib and imatinib potency and selectivity were compared. Inhaled seralutinib pharmacokinetics/pharmacodynamics were studied in healthy rats. Efficacy was evaluated in two rat models of PAH: SU5416/Hypoxia (SU5416/H) and monocrotaline pneumonectomy (MCTPN). Effects on inflammatory/cytokine signalling were examined. PDGFR, CSF1R and c-KIT immunohistochemistry in rat and human PAH lung samples and microRNA (miRNA) analysis in the SU5416/H model were performed. RESULTS: Seralutinib potently inhibited PDGFRα/ß, CSF1R and c-KIT. Inhaled seralutinib demonstrated dose-dependent inhibition of lung PDGFR and c-KIT signalling and increased bone morphogenetic protein receptor type 2 (BMPR2). Seralutinib improved cardiopulmonary haemodynamic parameters and reduced small pulmonary artery muscularisation and right ventricle hypertrophy in both models. In the SU5416/H model, seralutinib improved cardiopulmonary haemodynamic parameters, restored lung BMPR2 protein levels and decreased N-terminal pro-brain natriuretic peptide (NT-proBNP), more than imatinib. Quantitative immunohistochemistry in human lung PAH samples demonstrated increased PDGFR, CSF1R and c-KIT. miRNA analysis revealed candidates that could mediate seralutinib effects on BMPR2. CONCLUSIONS: Inhaled seralutinib was an effective treatment of severe PAH in two animal models, with improved cardiopulmonary haemodynamic parameters, a reduction in NT-proBNP, reverse remodelling of pulmonary vascular pathology and improvement in inflammatory biomarkers. Seralutinib showed greater efficacy compared to imatinib in a preclinical study.


Assuntos
Hipertensão Pulmonar , MicroRNAs , Hipertensão Arterial Pulmonar , Ratos , Humanos , Animais , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/metabolismo , Mesilato de Imatinib/uso terapêutico , Monocrotalina , Hipertensão Pulmonar Primária Familiar , Artéria Pulmonar , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Hipóxia , MicroRNAs/metabolismo , Modelos Animais de Doenças
8.
PLoS Pathog ; 16(3): e1008386, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32208455

RESUMO

Initial cell attachment of rotavirus (RV) to specific cell surface glycan receptors, which is the essential first step in RV infection, is mediated by the VP8* domain of the spike protein VP4. Recently, human histo-blood group antigens (HBGAs) have been identified as receptors or attachment factors for human RV strains. RV strains in the P[4] and P[8] genotypes of the P[II] genogroup share common recognition of the Lewis b (Leb) and H type 1 antigens, however, the molecular basis of receptor recognition by the major human P[8] RVs remains unknown due to lack of experimental structural information. Here, we used nuclear magnetic resonance (NMR) spectroscopy-based titration experiments and NMR-derived high ambiguity driven docking (HADDOCK) methods to elucidate the molecular basis for P[8] VP8* recognition of the Leb (LNDFH I) and type 1 HBGAs. We also used X-ray crystallography to determine the molecular details underlying P[6] recognition of H type 1 HBGAs. Unlike P[6]/P[19] VP8*s that recognize H type 1 HBGAs in a binding surface composed of an α-helix and a ß-sheet, referred as the "ßα binding site", the P[8] and P[4] VP8*s bind Leb HBGAs in a previously undescribed pocket formed by the edges of two ß-sheets, referred to as the "ßß binding site". Importantly, the P[8] and P[4] VP8*s retain binding capability to non-Leb type 1 HBGAs using the ßα binding site. The presence of two distinct binding sites for Leb and non-Leb HBGA glycans in the P[8] and P[4] VP8* domains suggests host-pathogen co-evolution under structural and functional adaptation of RV pathogens to host glycan polymorphisms. Assessment and understanding of the precise impact of this co-evolutionary process in determining RV host ranges and cross-species RV transmission should facilitate improved RV vaccine development and prediction of future RV strain emergence and epidemics.


Assuntos
Proteínas do Capsídeo/química , Antígenos do Grupo Sanguíneo de Lewis/química , Simulação de Acoplamento Molecular , Rotavirus/química , Proteínas do Capsídeo/metabolismo , Células HT29 , Humanos , Antígenos do Grupo Sanguíneo de Lewis/metabolismo , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Rotavirus/metabolismo
9.
Ann Surg Oncol ; 29(12): 7410-7420, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35879482

RESUMO

BACKGROUND: Surgery results in severe impairment of natural killer (NK) cell cytotoxicity (NKC) and activity (NKA, cytokine secretion), and a dramatic drop in arginine levels. Postoperative immunosuppression is associated with increased complications and recurrence. Perioperative arginine is reported to reduce postoperative complications. Because arginine modulates NK cell function, this study aimed to determine whether perioperative consumption of arginine-enriched supplements (AES) can improve NK cell function in colorectal cancer (CRC) surgery patients. METHODS: This study randomized 24 CRC patients to receive the AES or isocaloric/isonitrogenous control supplement three times a day for five days before and after surgery. The AES contained 4.2 g of arginine per dose (12.6 g/day). The primary objective was to determine whether AES improved NKC by 50 % compared with the control group after surgery. RESULTS: On surgery day (SD) 1, NKC was significantly reduced postoperatively in the control group by 50 % (interquartile range [IQR], 36-55 %; p = 0.02) but not in the AES group (25 % reduction; IQR, 28-75 %; p = 0.3). Furthermore, AES had no benefit in terms of NKA or NK cell number. Compliance was much greater preoperatively (>91 %) than postoperatively (<46 %). However, despite excellent preoperative compliance, arginine was rapidly cleared from the blood within 4 h after consumption and therefore, did not prevent the postoperative drop in arginine. CONCLUSIONS: Oral consumption of arginine immunonutrition resulted in a modest improvement in NKC after surgery but was unable to prevent postoperative arginine depletion or the suppression of NKA (ClinicalTrials.gov NCT02987296).


Assuntos
Arginina , Neoplasias Colorretais , Neoplasias Colorretais/cirurgia , Citocinas , Humanos , Células Matadoras Naturais , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos
10.
Cytotherapy ; 24(10): 979-989, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35562303

RESUMO

Autologous whole cell vaccines use a patient's own tumor cells as a source of antigen to elicit an anti-tumor immune response in vivo. Recently, the authors conducted a systematic review of clinical trials employing these products in hematological cancers that showed a favorable safety profile and trend toward efficacy. However, it was noted that manufacturing challenges limit both the efficacy and clinical implementation of these vaccine products. In the current literature review, the authors sought to define the issues surrounding the manufacture of autologous whole cell products for hematological cancers. The authors describe key factors, including the acquisition, culture, cryopreservation and transduction of malignant cells, that require optimization for further advancement of the field. Furthermore, the authors provide a summary of pre-clinical work that informs how the identified challenges may be overcome. The authors also highlight areas in which future basic research would be of benefit to the field. The goal of this review is to provide a roadmap for investigators seeking to advance the field of autologous cell vaccines as it applies to hematological malignancies.


Assuntos
Vacinas Anticâncer , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Neoplasias , Neoplasias Hematológicas/terapia , Humanos , Transplante Autólogo
11.
Mol Cell ; 53(2): 330-43, 2014 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-24462206

RESUMO

While structural symmetry is a prevailing feature of homo-oligomeric proteins, asymmetry provides unique mechanistic opportunities. We present the crystal structure of full-length TRAP1, the mitochondrial Hsp90 molecular chaperone, in a catalytically active closed state. The TRAP1 homodimer adopts a distinct, asymmetric conformation, where one protomer is reconfigured via a helix swap at the middle:C-terminal domain (MD:CTD) interface. This interface plays a critical role in client binding. Solution methods validate the asymmetry and show extension to Hsp90 homologs. Point mutations that disrupt unique contacts at each MD:CTD interface reduce catalytic activity and substrate binding and demonstrate that each protomer needs access to both conformations. Crystallographic data on a dimeric NTD:MD fragment suggests that asymmetry arises from strain induced by simultaneous NTD and CTD dimerization. The observed asymmetry provides the potential for an additional step in the ATPase cycle, allowing sequential ATP hydrolysis steps to drive both client remodeling and client release.


Assuntos
Trifosfato de Adenosina/metabolismo , Fator 1 Associado a Receptor de TNF/química , Proteínas de Peixe-Zebra/química , Cristalografia por Raios X , Hidrólise , Estrutura Terciária de Proteína , Fator 1 Associado a Receptor de TNF/metabolismo , Fator 1 Associado a Receptor de TNF/fisiologia , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/fisiologia
12.
Intern Med J ; 52(9): 1471-1477, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35191178

RESUMO

The World Anti-Doping Agency now allows cannabidiol (CBD) to be taken in elite sport, but has retained all other cannabinoids on its banned list. This, together with liberalisation of cannabis laws, has led to an increasing interest in its use in sport. This includes commercial sponsorship of sporting events and highlights the need for accurate information to be readily available to athletes and their advisers. This narrative review confirms that CBD and tetrahydrocannabinol (THC) do not enhance performance. CBD possesses anti-inflammatory and analgesic properties that have not been adequately evaluated in the area of sport. Some formulations of CBD contain THC or other cannabinoids that may result in a positive drug test.


Assuntos
Canabidiol , Canabinoides , Cannabis , Analgésicos , Dronabinol/farmacologia , Humanos
13.
Nucleic Acids Res ; 48(1): 432-444, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31713614

RESUMO

SP_0782 from Streptococcus pneumoniae is a dimeric protein that potentially binds with single-stranded DNA (ssDNA) in a manner similar to human PC4, the prototype of PC4-like proteins, which plays roles in transcription and maintenance of genome stability. In a previous NMR study, SP_0782 exhibited an ssDNA-binding property different from YdbC, a prokaryotic PC4-like protein from Lactococcus lactis, but the underlying mechanism remains unclear. Here, we show that although SP_0782 adopts an overall fold similar to those of PC4 and YdbC, the ssDNA length occupied by SP_0782 is shorter than those occupied by PC4 and YdbC. SP_0782 exhibits varied binding patterns for different lengths of ssDNA, and tends to form large complexes with ssDNA in a potential high-density binding manner. The structures of SP_0782 complexed with different ssDNAs reveal that the varied binding patterns are associated with distinct capture of nucleotides in two major DNA-binding regions of SP_0782. Moreover, a comparison of known structures of PC4-like proteins complexed with ssDNA reveals a divergence in the binding interface between prokaryotic and eukaryotic PC4-like proteins. This study provides insights into the ssDNA-binding mechanism of PC4-like proteins, and benefits further study regarding the biological function of SP_0782, probably in DNA protection and natural transformation.


Assuntos
Proteínas de Bactérias/química , DNA Bacteriano/química , DNA de Cadeia Simples/química , Proteínas de Ligação a DNA/química , Streptococcus pneumoniae/genética , Fatores de Transcrição/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Cristalografia por Raios X , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Cinética , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Modelos Moleculares , Conformação de Ácido Nucleico , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Dobramento de Proteína , Domínios e Motivos de Interação entre Proteínas , Streptococcus pneumoniae/metabolismo , Termodinâmica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Int J Mol Sci ; 23(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36498937

RESUMO

Natural Killer (NK) cell cytotoxicity and interferon-gamma (IFNγ) production are profoundly suppressed postoperatively. This dysfunction is associated with increased morbidity and cancer recurrence. NK activity depends on the integration of activating and inhibitory signals, which may be modulated by transforming growth factor-beta (TGF-ß). We hypothesized that impaired postoperative NK cell IFNγ production is due to altered signaling pathways caused by postoperative TGF-ß. NK cell receptor expression, downstream phosphorylated targets, and IFNγ production were assessed using peripheral blood mononuclear cells (PBMCs) from patients undergoing cancer surgery. Healthy NK cells were incubated in the presence of healthy/baseline/postoperative day (POD) 1 plasma and in the presence/absence of a TGF-ß-blocking monoclonal antibody (mAb) or the small molecule inhibitor (smi) SB525334. Single-cell RNA sequencing (scRNA-seq) was performed on PBMCs from six patients with colorectal cancer having surgery at baseline/on POD1. Intracellular IFNγ, activating receptors (CD132, CD212, NKG2D, DNAM-1), and downstream target (STAT5, STAT4, p38 MAPK, S6) phosphorylation were significantly reduced on POD1. Furthermore, this dysfunction was phenocopied in healthy NK cells through incubation with rTGF-ß1 or POD1 plasma and was prevented by the addition of anti-TGF-ß immunotherapeutics (anti-TGF-ß mAb or TGF-ßR smi). Targeted gene analysis revealed significant decreases in S6 and FKBP12, an increase in Shp-2, and a reduction in NK metabolism-associated transcripts on POD1. pSmad2/3 was increased and pS6 was reduced in response to rTGF-ß1 on POD1, changes that were prevented by anti-TGF-ß immunotherapeutics. Together, these results suggest that both canonical and mTOR pathways downstream of TGF-ß mediate phenotypic changes that result in postoperative NK cell dysfunction.


Assuntos
Células Matadoras Naturais , Neoplasias , Fator de Crescimento Transformador beta , Humanos , Leucócitos Mononucleares/metabolismo , Neoplasias/cirurgia , Receptores de Células Matadoras Naturais/metabolismo , Fator de Crescimento Transformador beta/antagonistas & inibidores , Anticorpos Monoclonais
15.
Am J Physiol Renal Physiol ; 320(5): F984-F1000, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33843271

RESUMO

Sepsis-associated acute kidney injury (SA-AKI) is a significant problem in the critically ill that causes increased death. Emerging understanding of this disease implicates metabolic dysfunction in its pathophysiology. This study sought to identify specific metabolic pathways amenable to potential therapeutic intervention. Using a murine model of sepsis, blood and tissue samples were collected for assessment of systemic inflammation, kidney function, and renal injury. Nuclear magnetic resonance (NMR)-based metabolomics quantified dozens of metabolites in serum and urine that were subsequently submitted to pathway analysis. Kidney tissue gene expression analysis confirmed the implicated pathways. Septic mice had elevated circulating levels of inflammatory cytokines and increased levels of blood urea nitrogen and creatinine, indicating both systemic inflammation and poor kidney function. Renal tissue showed only mild histological evidence of injury in sepsis. NMR metabolomic analysis identified the involvement of mitochondrial pathways associated with branched-chain amino acid metabolism, fatty acid oxidation, and de novo NAD+ biosynthesis in SA-AKI. Renal cortical gene expression of enzymes associated with those pathways was predominantly suppressed. Renal cortical fatty acid oxidation rates were lower in septic mice with high inflammation, and this correlated with higher serum creatinine levels. Similar to humans, septic mice demonstrated renal dysfunction without significant tissue disruption, pointing to metabolic derangement as an important contributor to SA-AKI pathophysiology. Metabolism of branched-chain amino acid and fatty acids and NAD+ synthesis, which all center on mitochondrial function, appeared to be suppressed. Developing interventions to activate these pathways may provide new therapeutic opportunities for SA-AKI.NEW & NOTEWORTHY NMR-based metabolomics revealed disruptions in branched-chain amino acid metabolism, fatty acid oxidation, and NAD+ synthesis in sepsis-associated acute kidney injury. These pathways represent essential processes for energy provision in renal tubular epithelial cells and may represent targetable mechanisms for therapeutic intervention.


Assuntos
Injúria Renal Aguda/sangue , Injúria Renal Aguda/urina , Imageamento por Ressonância Magnética/métodos , Metabolômica/métodos , Mitocôndrias/metabolismo , Sepse/complicações , Animais , Biomarcadores/sangue , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica , Inflamação/sangue , Inflamação/metabolismo , Inflamação/urina , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
Hematol Oncol ; 39(4): 448-464, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33963789

RESUMO

Autologous cell vaccines use a patient's tumor cells to stimulate a broad antitumor response in vivo. This approach shows promise for treating hematologic cancers in early phase clinical trials, but overall safety and efficacy remain poorly described. We conducted a systematic review assessing the use of autologous cell vaccination in treating hematologic cancers. Primary outcomes of interest were safety and clinical response, with secondary outcomes including survival, relapse rate, correlative immune assays and health-quality related metrics. We performed a search of MEDLINE, Embase and the Cochrane Register of Controlled Trials including any interventional trial employing an autologous, whole cell product in any hematologic malignancy. Risk of bias was assessed using a modified Institute of Health Economics tool. Across 20 single arm studies, only 341 of 592 enrolled participants received one or more vaccinations. Primary reasons for not receiving vaccination included rapid disease progression/death and manufacturing challenges. Overall, few high-grade adverse events were observed. One death was reported and attributed to a GM-CSF producing allogeneic cell line co-administered with the autologous vaccine. Of 58 evaluable patients, the complete response rate was 21.0% [95% CI, 10.4%-37.8%)] and overall response rate was 35.8% (95% CI, 24.4%-49.0%). Of 97 evaluable patients for survival, the 5-years overall survival rate was 64.9% (95% CI, 52.6%-77.2%) and disease-free survival was 59.7% (95% CI, 47.7%-71.7%). We conclude that, in hematologic malignancies, based on limited available data, autologous cell vaccines are safe and display a trend towards efficacy but that challenges exist in vaccine manufacture and administration.


Assuntos
Neoplasias Hematológicas/terapia , Vacinas/uso terapêutico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vacinas/farmacologia
17.
J Strength Cond Res ; 35(12): 3459-3465, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35133998

RESUMO

ABSTRACT: Falk Neto, JH, Parent, E, and Kennedy, MD. Long-term athlete development: Seasonal and longitudinal fitness changes in female university rugby players. J Strength Cond Res 35(12): 3459-3465, 2021-The Long-Term Athlete Development model is used by organizations to determine the expected improvements from athletes at different stages of their careers. For female rugby athletes, university sports should provide continued support for athlete development during the Training to Perform stage (18-21 years old). However, little evidence exists for longitudinal changes across years of participation in university sports in this group. The purpose of this study was to assess changes in anthropometric and fitness characteristics in female university rugby players across different seasons. Seventeen players were divided into forwards (n = 9, 21.1 ± 2.6 years) and backs (n = 8, 19.62 ± 0.9 years) and assessed across 5 points over 3 years: preseason 1, postseason 1, preseason 2, postseason 2, and preseason 3. Anthropometric (height, body mass, and body mass index) and performance measurements (grip strength, flexibility, trunk muscular endurance, upper-body muscular endurance, 40-m sprint, vertical jump, and 20-m shuttle run) were collected. V̇o2max was higher at preseason 2 compared with postseason 1 (p = 0.02), postseason 2 (p = 0.01), and preseason 3 (p = 0.015), and trunk muscular endurance was higher at preseason 3 (p = 0.02). Performance in the first 5 m of the sprint test decreased at postseason 1 (p = 0.018) and preseason 2 (p = 0.016) when compared with preseason 1. The results indicate that these female athletes did not improve their fitness across the Training to Perform stage when participating in university sports. These female rugby players likely developed their fitness at earlier stages and, at this stage, already possessed well-developed fitness levels, which were merely maintained throughout years.


Assuntos
Desempenho Atlético , Futebol Americano , Adolescente , Adulto , Atletas , Feminino , Humanos , Aptidão Física , Rugby , Estações do Ano , Universidades , Adulto Jovem
18.
Rural Remote Health ; 21(1): 6137, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33641336

RESUMO

INTRODUCTION: Kansas is a predominantly rural state that had 9853 rural births in 2018. The Kansas Rural Obstetrical Access Task Force was formed to study and address factors affecting these births. One of these factors is the distance between mothers and the location of maternity services. Poor access leading to increased travel times between mothers and maternity care providers has been associated with a greater rate of pregnancy complications, premature birth, and higher cost of care. In Kansas, the current state of access is not clearly described. Adding to the concern were reports of rural hospital closures and provider cessation of maternity care services. This was likely leading to 'maternity deserts': entire counties that have no maternity care providers. The goal of this project was to identify who currently delivers babies in Kansas, map their location, and determine future plans for maternity care service provision. METHODS: The study began by dividing the state of Kansas into counties by population density and by identifying current practitioners in the state. Once identified, providers were sent a 72-item mixed methods survey with content including demographics, practice location, provision of maternity care, and intents on future practice changes. RESULTS: Analysis of the survey responses led to a clearer picture of the current state of maternity care provider distribution in Kansas. This revealed multiple existing maternity deserts and a projected expansion of these deserts over the next 10 years. CONCLUSION: The current distribution of maternity care services in Kansas reveals numerous maternity deserts, and provider survey projections as far forward as 2030 show expansion of these deserts. This poor access to care may be contributing to unnecessary pregnancy complications. With the extent of this issue identified, targeted efforts toward narrowing the current and expanding maternity deserts are being implemented.


Assuntos
Serviços de Saúde Materna , Estudos Transversais , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Kansas/epidemiologia , Gravidez , População Rural
19.
Proteins ; 88(11): 1493-1512, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32548861

RESUMO

Pentapeptide repeat proteins (PRPs) represent a large superfamily with more than 38 000 sequences in nearly 3500 species, the majority belonging to cyanobacteria but represented among all branches of life. PRPs contain at least eight consecutive pentapeptide repeats with the consensus (A/C/S/V/T/L/I)(D/N/S/K/E/I/R)(L/F)(S/T/R/E/Q/K/V/D)(G/D/E/N/R/Q/K). PRPs fold into right-handed quadrilateral ß helices, also known as repeat-five-residue (Rfr)-folds, with four consecutive pentapeptide repeats comprising a single coil, the ~90° change in polypeptide direction in square-shaped coils achieved by type I, II and IV ß turns, and hydrogen bonds between coils establishing ß ladders on each Rfr-fold face. PRPs are broadly categorized into group 1 and 2 involved in antibiotic resistance and group 3 currently having unknown functions. Motivated by their intriguing structures, we are investigating PRP biophysical characteristics, including Rfr-fold thermal stability, ß turn and ß ladder hydrogen bond amide exchange rates and backbone dynamics. Here, we present analysis of 20 ns molecular dynamics (MD) simulations and all atom normal mode analysis (aaNMA) calculations for four group 1 and group 2 and four group 3 PRPs whose structures have been determined by X-ray crystallography. The MD cross-correlation matrices and aaNMA indicated strong correlated motion between adjacent coils and weak coupled motion between coils separated by one or more intervening coils. Slow anticorrelated motions were detected between adjacent coils in aaNMA modes that we hypothesize are requisite to access exchange-competent states necessary to permit solvent exchange of amide hydrogens involved in ß-ladder and ß-turns hydrogen bonds, which can have lifetimes on the order of months.


Assuntos
Proteínas de Bactérias/química , Simulação de Dinâmica Molecular , Oligopeptídeos/química , Dobramento de Proteína , Animais , Arabidopsis/química , Arabidopsis/metabolismo , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Cianobactérias/química , Cianobactérias/metabolismo , Medição da Troca de Deutério , Humanos , Ligação de Hidrogênio , Oligopeptídeos/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Estabilidade Proteica , Sequências Repetitivas de Aminoácidos , Termodinâmica
20.
Proteins ; 88(9): 1143-1153, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32092202

RESUMO

Nostoc sp. PCC 7120 are filamentous cyanobacteria capable of both oxygenic photosynthesis and nitrogen fixation, with the latter taking place in specialized cells known as heterocysts that terminally differentiate from vegetative cells under conditions of nitrogen starvation. Cyanobacteria have existed on earth for more than 2 billion years and are thought to be responsible for oxygenation of the earth's atmosphere. Filamentous cyanobacteria such as Nostoc sp. PCC 7120 may also represent the oldest multicellular organisms on earth that undergo cell differentiation. Pentapeptide repeat proteins (PRPs), which occur most abundantly in cyanobacteria, adopt a right-handed quadrilateral ß-helical structure, also referred to as a repeat five residue (Rfr) fold, with four-consecutive pentapeptide repeats constituting a single coil in the ß-helical structure. PRPs are predicted to exist in all compartments within cyanobacteria including the thylakoid and cell-wall membranes as well as the cytoplasm and thylakoid periplasmic space. Despite their intriguing structure and importance to understanding ancient cyanobacteria, the biochemical function of PRPs in cyanobacteria remains largely unknown. Here we report the crystal structure of Alr1298, a PRP from Nostoc sp. PCC 7120 predicted to reside in the cytoplasm. The structure displays the typical right-handed quadrilateral ß-helical structure and includes a four-α-helix cluster capping the N-terminus and a single α-helix capping the C-terminus. A gene cluster analysis indicated that Alr1298 may belong to an operon linked to cell proliferation and/or thylakoid biogenesis. Elevated alr1298 gene expression following nitrogen starvation indicates that Alr1298 may play a role in response to nitrogen starvation and/or heterocyst differentiation.


Assuntos
Proteínas de Bactérias/química , Nostoc/química , Oligopeptídeos/química , Oxigênio/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Parede Celular/química , Parede Celular/metabolismo , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Modelos Moleculares , Fixação de Nitrogênio/fisiologia , Nostoc/metabolismo , Oligopeptídeos/genética , Oligopeptídeos/metabolismo , Oxirredução , Oxigênio/metabolismo , Fotossíntese/fisiologia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Termodinâmica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA