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1.
Nat Immunol ; 22(7): 880-892, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099917

RESUMO

Multidimensional single-cell analyses of T cells have fueled the debate about whether there is extensive plasticity or 'mixed' priming of helper T cell subsets in vivo. Here, we developed an experimental framework to probe the idea that the site of priming in the systemic immune compartment is a determinant of helper T cell-induced immunopathology in remote organs. By site-specific in vivo labeling of antigen-specific T cells in inguinal (i) or gut draining mesenteric (m) lymph nodes, we show that i-T cells and m-T cells isolated from the inflamed central nervous system (CNS) in a model of multiple sclerosis (MS) are distinct. i-T cells were Cxcr6+, and m-T cells expressed P2rx7. Notably, m-T cells infiltrated white matter, while i-T cells were also recruited to gray matter. Therefore, we propose that the definition of helper T cell subsets by their site of priming may guide an advanced understanding of helper T cell biology in health and disease.


Assuntos
Autoimunidade , Encéfalo/imunologia , Linhagem da Célula , Encefalomielite Autoimune Experimental/imunologia , Intestinos/imunologia , Pele/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Transferência Adotiva , Animais , Autoimunidade/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Sinalização do Cálcio , Líquido Cefalorraquidiano/imunologia , Líquido Cefalorraquidiano/metabolismo , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/metabolismo , Cloridrato de Fingolimode/farmacologia , Perfilação da Expressão Gênica , Genes Codificadores dos Receptores de Linfócitos T , Células HEK293 , Humanos , Imunossupressores/farmacologia , Intestinos/efeitos dos fármacos , Microscopia Intravital , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia de Fluorescência , Esclerose Múltipla Recidivante-Remitente/genética , Esclerose Múltipla Recidivante-Remitente/imunologia , Esclerose Múltipla Recidivante-Remitente/metabolismo , Fenótipo , Estudos Prospectivos , RNA-Seq , Receptores CXCR6/genética , Receptores CXCR6/metabolismo , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo , Análise de Célula Única , Pele/efeitos dos fármacos , Pele/metabolismo , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T Auxiliares-Indutores/transplante , Transcriptoma
2.
Nature ; 616(7957): 543-552, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37046093

RESUMO

Intratumour heterogeneity (ITH) fuels lung cancer evolution, which leads to immune evasion and resistance to therapy1. Here, using paired whole-exome and RNA sequencing data, we investigate intratumour transcriptomic diversity in 354 non-small cell lung cancer tumours from 347 out of the first 421 patients prospectively recruited into the TRACERx study2,3. Analyses of 947 tumour regions, representing both primary and metastatic disease, alongside 96 tumour-adjacent normal tissue samples implicate the transcriptome as a major source of phenotypic variation. Gene expression levels and ITH relate to patterns of positive and negative selection during tumour evolution. We observe frequent copy number-independent allele-specific expression that is linked to epigenomic dysfunction. Allele-specific expression can also result in genomic-transcriptomic parallel evolution, which converges on cancer gene disruption. We extract signatures of RNA single-base substitutions and link their aetiology to the activity of the RNA-editing enzymes ADAR and APOBEC3A, thereby revealing otherwise undetected ongoing APOBEC activity in tumours. Characterizing the transcriptomes of primary-metastatic tumour pairs, we combine multiple machine-learning approaches that leverage genomic and transcriptomic variables to link metastasis-seeding potential to the evolutionary context of mutations and increased proliferation within primary tumour regions. These results highlight the interplay between the genome and transcriptome in influencing ITH, lung cancer evolution and metastasis.


Assuntos
Evolução Molecular , Genoma Humano , Neoplasias Pulmonares , Metástase Neoplásica , Transcriptoma , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Genômica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Metástase Neoplásica/genética , Transcriptoma/genética , Alelos , Aprendizado de Máquina , Genoma Humano/genética
3.
Plant J ; 117(4): 1281-1297, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37965720

RESUMO

Phytoplasmas are pathogenic bacteria that reprogram plant host development for their own benefit. Previous studies have characterized a few different phytoplasma effector proteins that destabilize specific plant transcription factors. However, these are only a small fraction of the potential effectors used by phytoplasmas; therefore, the molecular mechanisms through which phytoplasmas modulate their hosts require further investigation. To obtain further insights into the phytoplasma infection mechanisms, we generated a protein-protein interaction network between a broad set of phytoplasma effectors and a large, unbiased collection of Arabidopsis thaliana transcription factors and transcriptional regulators. We found widespread, but specific, interactions between phytoplasma effectors and host transcription factors, especially those related to host developmental processes. In particular, many unrelated effectors target specific sets of TCP transcription factors, which regulate plant development and immunity. Comparison with other host-pathogen protein interaction networks shows that phytoplasma effectors have unusual targets, indicating that phytoplasmas have evolved a unique and unusual infection strategy. This study contributes a rich and solid data source that guides further investigations of the functions of individual effectors, as demonstrated for some herein. Moreover, the dataset provides insights into the underlying molecular mechanisms of phytoplasma infection.


Assuntos
Arabidopsis , Phytoplasma , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Plantas/metabolismo , Arabidopsis/metabolismo , Mapeamento de Interação de Proteínas , Doenças das Plantas/microbiologia
4.
Am J Hum Genet ; 109(9): 1713-1723, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35948005

RESUMO

The leucine-rich glioma-inactivated (LGI) family consists of four highly conserved paralogous genes, LGI1-4, that are highly expressed in mammalian central and/or peripheral nervous systems. LGI1 antibodies are detected in subjects with autoimmune limbic encephalitis and peripheral nerve hyperexcitability syndromes (PNHSs) such as Isaacs and Morvan syndromes. Pathogenic variations of LGI1 and LGI4 are associated with neurological disorders as disease traits including familial temporal lobe epilepsy and neurogenic arthrogryposis multiplex congenita 1 with myelin defects, respectively. No human disease has been reported associated with either LGI2 or LGI3. We implemented exome sequencing and family-based genomics to identify individuals with deleterious variants in LGI3 and utilized GeneMatcher to connect practitioners and researchers worldwide to investigate the clinical and electrophysiological phenotype in affected subjects. We also generated Lgi3-null mice and performed peripheral nerve dissection and immunohistochemistry to examine the juxtaparanode LGI3 microarchitecture. As a result, we identified 16 individuals from eight unrelated families with loss-of-function (LoF) bi-allelic variants in LGI3. Deep phenotypic characterization showed LGI3 LoF causes a potentially clinically recognizable PNHS trait characterized by global developmental delay, intellectual disability, distal deformities with diminished reflexes, visible facial myokymia, and distinctive electromyographic features suggestive of motor nerve instability. Lgi3-null mice showed reduced and mis-localized Kv1 channel complexes in myelinated peripheral axons. Our data demonstrate bi-allelic LoF variants in LGI3 cause a clinically distinguishable disease trait of PNHS, most likely caused by disturbed Kv1 channel distribution in the absence of LGI3.


Assuntos
Mioquimia , Proteínas do Tecido Nervoso , Animais , Autoanticorpos , Axônios , Genômica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mamíferos/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Fenótipo , Genética Reversa
5.
Brain ; 147(4): 1399-1411, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37972275

RESUMO

The most frequent neurodegenerative proteinopathies include diseases with deposition of misfolded tau or α-synuclein in the brain. Pathological protein aggregates in the PNS are well-recognized in α-synucleinopathies and have recently attracted attention as a diagnostic biomarker. However, there is a paucity of observations in tauopathies. To characterize the involvement of the PNS in tauopathies, we investigated tau pathology in cranial and spinal nerves (PNS-tau) in 54 tauopathy cases [progressive supranuclear palsy (PSP), n = 15; Alzheimer's disease (AD), n = 18; chronic traumatic encephalopathy (CTE), n = 5; and corticobasal degeneration (CBD), n = 6; Pick's disease, n = 9; limbic-predominant neuronal inclusion body 4-repeat tauopathy (LNT), n = 1] using immunohistochemistry, Gallyas silver staining, biochemistry, and seeding assays. Most PSP cases revealed phosphorylated and 4-repeat tau immunoreactive tau deposits in the PNS as follows: (number of tau-positive cases/available cases) cranial nerves III: 7/8 (88%); IX/X: 10/11 (91%); and XII: 6/6 (100%); anterior spinal roots: 10/10 (100%). The tau-positive inclusions in PSP often showed structures with fibrillary (neurofibrillary tangle-like) morphology in the axon that were also recognized with Gallyas silver staining. CBD cases rarely showed fine granular non-argyrophilic tau deposits. In contrast, tau pathology in the PNS was not evident in AD, CTE and Pick's disease cases. The single LNT case also showed tau pathology in the PNS. In PSP, the severity of PNS-tau involvement correlated with that of the corresponding nuclei, although, occasionally, p-tau deposits were present in the cranial nerves but not in the related brainstem nuclei. Not surprisingly, most of the PSP cases presented with eye movement disorder and bulbar symptoms, and some cases also showed lower-motor neuron signs. Using tau biosensor cells, for the first time we demonstrated seeding capacity of tau in the PNS. In conclusion, prominent PNS-tau distinguishes PSP from other tauopathies. The morphological differences of PNS-tau between PSP and CBD suggest that the tau pathology in PNS could reflect that in the central nervous system. The high frequency and early presence of tau lesions in PSP suggest that PNS-tau may have clinical and biomarker relevance.


Assuntos
Doença de Alzheimer , Doença de Pick , Paralisia Supranuclear Progressiva , Tauopatias , Humanos , Paralisia Supranuclear Progressiva/patologia , Proteínas tau/metabolismo , Doença de Pick/patologia , Doença de Alzheimer/patologia , Tauopatias/patologia , Nervos Espinhais , Biomarcadores
6.
Proteins ; 92(7): 874-885, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38477414

RESUMO

Aquaporin (AQP) is a water channel protein from the family of transmembrane proteins which facilitates the movement of water across the cell membrane. It is ubiquitous in nature, however the understanding of the water transport mechanism, especially for AQPs in microbes adapted to low temperatures, remains limited. AQP also has been recognized for its ability to be used for water filtration, but knowledge of the biochemical features necessary for its potential applications in industrial processes has been lacking. Therefore, this research was conducted to express, extract, solubilize, purify, and study the functional adaptations of the aquaporin Z family from Pseudomonas sp. AMS3 via molecular approaches. In this study, AqpZ1 AMS3 was successfully subcloned and expressed in E. coli BL21 (DE3) as a recombinant protein. The AqpZ1 AMS3 gene was expressed under optimized conditions and the best optimized condition for the AQP was in 0.5 mM IPTG incubated at 25°C for 20 h induction time. A zwitterionic mild detergent [(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate was the suitable surfactant for the protein solubilization. The protein was then purified via affinity chromatography. Liposome and proteoliposome was reconstituted to determine the particle size using dynamic light scattering. This information obtained from this psychrophilic AQP identified provides new insights into the structural adaptation of this protein at low temperatures and could be useful for low temperature application and molecular engineering purposes in the future.


Assuntos
Aquaporinas , Proteínas de Bactérias , Clonagem Molecular , Escherichia coli , Pseudomonas , Proteínas Recombinantes , Pseudomonas/metabolismo , Pseudomonas/genética , Pseudomonas/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Escherichia coli/genética , Escherichia coli/metabolismo , Aquaporinas/química , Aquaporinas/genética , Aquaporinas/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Expressão Gênica , Proteolipídeos/metabolismo , Proteolipídeos/química , Regiões Antárticas , Lipossomos/metabolismo , Lipossomos/química , Água/química , Água/metabolismo , Solubilidade , Sequência de Aminoácidos
7.
Thorax ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38906696

RESUMO

INTRODUCTION: Given the heterogeneity of sarcoidosis, predicting disease course of patients remains a challenge. Our aim was to determine whether the 3-year change in pulmonary function differed between pulmonary function phenotypes and whether there were differential longitudinal changes by race and sex. METHODS: We identified individuals seen between 2005 and 2015 with a confirmed diagnosis of sarcoidosis who had at least two pulmonary function test measurements within 3 years of entry into the cohort. For each individual, spirometry, diffusion capacity, Charlson Comorbidity Index, sarcoidosis organ involvement, diagnosis duration, tobacco use, race, sex, age and medications were recorded. We compared changes in pulmonary function by type of pulmonary function phenotype and for demographic groups. RESULTS: Of 291 individuals, 59% (173) were female and 54% (156) were black. Individuals with restrictive pulmonary function phenotype had significantly greater 3-year rate of decline of FVC% (forced vital capacity) predicted and FEV1% (forced expiratory volume in 1 s) predicted course when compared with normal phenotype. We identified a subset of individuals in the cohort, highest decliners, who had a median 3-year FVC decline of 156 mL. Black individuals had worse pulmonary function at entry into the cohort measured by FVC% predicted, FEV1% predicted and diffusing capacity for carbon monoxide % predicted compared with white individuals. Black individuals' pulmonary function remained stable or declined over time, whereas white individuals' pulmonary function improved over time. There were no sex differences in rate of change in any pulmonary function parameters. SUMMARY: We found significant differences in 3-year change in pulmonary function among pulmonary function phenotypes and races, but no difference between sexes.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38847760

RESUMO

Chronic exercise training is associated with an 'athlete's artery' phenotype in young adults and an attenuated age-related decline in endothelium-dependent arterial function. Adolescence is associated with an influx of sex-specific hormones that may exert divergent effects on endothelial function, but whether training adaptations interact with biological maturation to produce a 'youth athlete's artery' has not been explored. We investigated the influence of exercise training-status on endothelium-dependent arterial function during childhood and adolescence. Brachial artery flow mediated dilation (FMD) was assessed in n=102 exercise-trained (males: n=25, females: n=29) and untrained (males: n=23, females: n=25) youths, characterised as pre- (males: n=25, females: n=26) or post- (males: n=23, females: n=28) predicted age at peak height velocity (PHV). Baseline brachial artery diameter was larger in post- compared to pre-PHV youths (P≤0.001), males compared to females (P≤0.001), and trained compared to untrained youths (3.26 ± 0.51mm vs 3.11 ± 0.42mm; P=0.041). Brachial FMD was similar in pre- and post-PHV youths (P=0.298), and males and females (P=0.946). However, exercise trained youths demonstrated higher FMD when compared to untrained counterparts (5.3 ± 3.3% vs 3.0 ± 2.6%; P≤0.001). Furthermore, brachial artery diameter (r2=0.142; P=0.007 vs r2=0.004; P=0.652) and FMD (r2=0.138; P=0.008 vs r2=0.003; P=0.706) were positively associated with cardiorespiratory fitness in post-, but not pre-PHV youths, respectively. Collectively, our data indicate that exercise training is associated with brachial artery remodeling and enhanced endothelial function during youth. However, arterial remodeling and endothelium-dependent function are only associated with elevated cardiorespiratory fitness during later stages of adolescence.

9.
Eur Respir J ; 63(2)2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38123239

RESUMO

BACKGROUND: Short-term studies suggest that dietary nitrate (NO3 -) supplementation may improve the cardiovascular risk profile, lowering blood pressure (BP) and enhancing endothelial function. It is not clear if these beneficial effects are sustained and whether they apply in people with COPD, who have a worse cardiovascular profile than those without COPD. Nitrate-rich beetroot juice (NR-BRJ) is a convenient dietary source of nitrate. METHODS: The ON-BC trial was a randomised, double-blind, placebo-controlled parallel group study in stable COPD patients with home systolic BP (SBP) measurement ≥130 mmHg. Participants were randomly allocated (1:1) using computer-generated, block randomisation to either 70 mL NR-BRJ (400 mg NO3 -) (n=40) or an otherwise identical nitrate-depleted placebo juice (0 mg NO3 -) (n=41), once daily for 12 weeks. The primary end-point was between-group change in home SBP measurement. Secondary outcomes included change in 6-min walk distance (6MWD) and measures of endothelial function (reactive hyperaemia index (RHI) and augmentation index normalised to a heart rate of 75 beats·min-1 (AIx75)) using an EndoPAT device. Plasma nitrate and platelet function were also measured. RESULTS: Compared with placebo, active treatment lowered SBP (Hodges-Lehmann treatment effect -4.5 (95% CI -5.9- -3.0) mmHg), and improved 6MWD (30.0 (95% CI 15.7-44.2) m; p<0.001), RHI (0.34 (95% CI 0.03-0.63); p=0.03) and AIx75 (-7.61% (95% CI -14.3- -0.95%); p=0.026). CONCLUSIONS: In people with COPD, prolonged dietary nitrate supplementation in the form of beetroot juice produces a sustained reduction in BP, associated with an improvement in endothelial function and exercise capacity.


Assuntos
Doenças Cardiovasculares , Doença Pulmonar Obstrutiva Crônica , Humanos , Nitratos/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/tratamento farmacológico , Suplementos Nutricionais , Fatores de Risco , Pressão Sanguínea , Antioxidantes , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Método Duplo-Cego , Estudos Cross-Over
10.
Small ; 20(12): e2304881, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37946631

RESUMO

InP/ZnS quantum dots (QDs) have received a large focus in recent years as a safer alternative to heavy metal-based QDs. Given their intrinsic fluorescent imaging capabilities, these QDs can be potentially relevant for in vivo platelet imaging. The InP/ZnS QDs are synthesized and their biocompatibility investigated through the use of different phase transfer agents. Analysis of platelet function indicates that platelet-QD interaction can occur at all concentrations and for all QD permutations tested. However, as the QD concentration increases, platelet aggregation is induced by QDs alone independent of natural platelet agonists. This study helps to define a range of concentrations and coatings (thioglycolic acid and penicillamine) that are biocompatible with platelet function. With this information, the platelet-QD interaction can be identified using multiple methods. Fluorescent lifetime imaging microscopy (FLIM) and confocal studies have shown QDs localize on the surface of the platelet toward the center while showing evidence of energy transfer within the QD population. It is believed that these findings are an important stepping point for the development of fluorescent probes for platelet imaging.


Assuntos
Pontos Quânticos , Ligantes
11.
BMC Microbiol ; 24(1): 176, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778276

RESUMO

BACKGROUND: Mangrove sediment microbes are increasingly attracting scientific attention due to their demonstrated capacity for diverse bioremediation activities, encompassing a wide range of environmental contaminants. MATERIALS AND METHODS: The microbial communities of five Avicennia marina mangrove sediment samples collected from Al Rayyis White Head, Red Sea (KSA), were characterized using Illumina amplicon sequencing of the 16S rRNA genes. RESULTS: Our study investigated the microbial composition and potential for organohalide bioremediation in five mangrove sediments from the Red Sea. While Proteobacteria dominated four microbiomes, Bacteroidetes dominated the fifth. Given the environmental concerns surrounding organohalides, their bioremediation is crucial. Encouragingly, we identified phylogenetically diverse organohalide-respiring bacteria (OHRB) across all samples, including Dehalogenimonas, Dehalococcoides, Anaeromyxobacter, Desulfuromonas, Geobacter, Desulfomonile, Desulfovibrio, Shewanella and Desulfitobacterium. These bacteria are known for their ability to dechlorinate organohalides through reductive dehalogenation. PICRUSt analysis further supported this potential, predicting the presence of functional biomarkers for organohalide respiration (OHR), including reductive dehalogenases targeting tetrachloroethene (PCE) and 3-chloro-4-hydroxyphenylacetate in most sediments. Enrichment cultures studies confirmed this prediction, demonstrating PCE dechlorination by the resident microbial community. PICRUSt also revealed a dominance of anaerobic metabolic processes, suggesting the microbiome's adaptation to the oxygen-limited environment of the sediments. CONCLUSION: This study provided insights into the bacterial community composition of five mangrove sediments from the Red Sea. Notably, diverse OHRB were detected across all samples, which possess the metabolic potential for organohalide bioremediation through reductive dehalogenation pathways. Furthermore, PICRUSt analysis predicted the presence of functional biomarkers for OHR in most sediments, suggesting potential intrinsic OHR activity by the enclosed microbial community.


Assuntos
Bactérias , Biodegradação Ambiental , Sedimentos Geológicos , Microbiota , Filogenia , RNA Ribossômico 16S , Sedimentos Geológicos/microbiologia , RNA Ribossômico 16S/genética , Microbiota/genética , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Bactérias/isolamento & purificação , Oceano Índico , Metagenômica , DNA Bacteriano/genética , Áreas Alagadas , Metagenoma
12.
Toxicol Appl Pharmacol ; 486: 116943, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38677600

RESUMO

Ulcerative colitis (UC) is an inflammatory condition that affects the colon's lining and increases the risk of colon cancer. Despite ongoing research, there is no identified cure for UC. The recognition of NLRP3 inflammasome activation in the pathogenesis of UC has gained widespread acceptance. Notably, the ketone body ß-hydroxybutyrate inhibits NLRP3 demonstrating its anti-inflammatory properties. Additionally, BD-AcAc 2 is ketone mono ester that increases ß-hydroxybutyrate blood levels. It has the potential to address the constraints associated with exogenous ß-hydroxybutyrate as a therapeutic agent, including issues related to stability and short duration of action. However, the effects of ß-hydroxybutyrate and BD-AcAc 2 on colitis have not been fully investigated. This study found that while both exogenous ß-hydroxybutyrate and BD-AcAc 2 produced the same levels of plasma ß-hydroxybutyrate, BD-AcAc 2 demonstrated superior effectiveness in mitigating dextran sodium sulfate-induced UC in rats. The mechanism of action involves modulating the NF-κB signaling, inhibiting the NLRP3 inflammasome, regulating antioxidant capacity, controlling tight junction protein expression and a potential to inhibit apoptosis and pyroptosis. Certainly, BD-AcAc 2's anti-inflammatory effects require more than just increasing plasma ß-hydroxybutyrate levels and other factors contribute to its efficacy. Local ketone concentrations in the gastrointestinal tract, as well as the combined effect of specific ketone bodies, are likely to have contributed to the stronger protective effect observed with ketone mono ester ingestion in our experiment. As a result, further investigations are necessary to fully understand the mechanisms of BD-AcAc 2 and optimize its use.


Assuntos
Ácido 3-Hidroxibutírico , Colite Ulcerativa , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Ácido 3-Hidroxibutírico/farmacologia , Ratos , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos Sprague-Dawley , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Sulfato de Dextrana/toxicidade , Colo/efeitos dos fármacos , Colo/patologia , Colo/metabolismo , NF-kappa B/metabolismo , Modelos Animais de Doenças , Transdução de Sinais/efeitos dos fármacos , Cetonas/farmacologia
13.
BMC Cancer ; 24(1): 131, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273265

RESUMO

BACKGROUND: Current guidelines advocate for colorectal cancer (CRC) screening in adults who are at risk by using direct visualization methods such as colonoscopy. However, in Egypt, there is a paucity of data regarding the current practice of colonoscopy screening. Moreover, more information is needed about the knowledge and attitudes of potential participants regarding the procedure and possible barriers that can limit their participation. METHODS: We conducted a nationwide cross-sectional study using an interview-based survey of patients aged 45 years or above who presented to outpatient clinics of nine university hospitals throughout Egypt. Participants were surveyed to assess their compliance with CRC colonoscopy screening guidelines, their knowledge of and attitude towards colonoscopy screening, and their perspective on potential barriers to colonoscopy screening. RESULTS: A total of 1,453 participants responded to our survey in the nine study centers. Only a minority of participants (2.3%) were referred for CRC screening. Referral rates were higher among those who knew someone with a history of CRC (5.3% vs 1.5%, p < 0.001) or had a discussion with their physician about CRC (25.8% vs 0.7%, p < 0.001). Few responders (3.2%) had good knowledge regarding CRC screening. After introducing the concept of CRC screening to all participants, most patients (66.7%) showed a positive attitude towards having the procedure. Financial burden and fear of results were the two most frequently cited barriers to undergoing CRC screening (81.1%; and 60.1%, respecteively). CONCLUSIONS: Despite the positive attitude, there is insufficient knowledge about CRC screening among eligible participants in Egypt. This has probably contributed to low compliance with current CRC screening guidelines and needs to be addressed at the national level.


Assuntos
Neoplasias Colorretais , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Humanos , Estudos Transversais , Egito/epidemiologia , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/métodos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Colonoscopia
14.
Brain Behav Immun ; 119: 494-506, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38657842

RESUMO

Alcohol Use Disorder (AUD) is a persistent condition linked to neuroinflammation, neuronal oxidative stress, and neurodegenerative processes. While the inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) has demonstrated effectiveness in reducing liver inflammation associated with alcohol, its impact on the brain remains largely unexplored. This study aimed to assess the effects of alirocumab, a monoclonal antibody targeting PCSK9 to lower systemic low-density lipoprotein cholesterol (LDL-C), on central nervous system (CNS) pathology in a rat model of chronic alcohol exposure. Alirocumab (50 mg/kg) or vehicle was administered weekly for six weeks in 32 male rats subjected to a 35 % ethanol liquid diet or a control liquid diet (n = 8 per group). The study evaluated PCSK9 expression, LDL receptor (LDLR) expression, oxidative stress, and neuroinflammatory markers in brain tissues. Chronic ethanol exposure increased PCSK9 expression in the brain, while alirocumab treatment significantly upregulated neuronal LDLR and reduced oxidative stress in neurons and brain vasculature (3-NT, p22phox). Alirocumab also mitigated ethanol-induced microglia recruitment in the cortex and hippocampus (Iba1). Additionally, alirocumab decreased the expression of pro-inflammatory cytokines and chemokines (TNF, CCL2, CXCL3) in whole brain tissue and attenuated the upregulation of adhesion molecules in brain vasculature (ICAM1, VCAM1, eSelectin). This study presents novel evidence that alirocumab diminishes oxidative stress and modifies neuroimmune interactions in the brain elicited by chronic ethanol exposure. Further investigation is needed to elucidate the mechanisms by which PCSK9 signaling influences the brain in the context of chronic ethanol exposure.


Assuntos
Anticorpos Monoclonais Humanizados , Encéfalo , Etanol , Neurônios , Estresse Oxidativo , Inibidores de PCSK9 , Pró-Proteína Convertase 9 , Animais , Estresse Oxidativo/efeitos dos fármacos , Masculino , Ratos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Inibidores de PCSK9/farmacologia , Pró-Proteína Convertase 9/metabolismo , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Anticorpos Monoclonais Humanizados/farmacologia , Alcoolismo/metabolismo , Alcoolismo/tratamento farmacológico , Microglia/metabolismo , Microglia/efeitos dos fármacos , Receptores de LDL/metabolismo , Ratos Sprague-Dawley , Modelos Animais de Doenças
15.
Gastrointest Endosc ; 99(6): 981-988.e5, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38103750

RESUMO

BACKGROUND AND AIMS: Jejunostomy tube placements provides enteral access for feeding in eligible patients who cannot meet their nutritional needs by mouth. They can be surgically placed laparoscopically (lap-J) or with the use of a conventional open laparotomy approach (open-J). Recently, direct percutaneous endoscopic jejunostomy (DPEJ) has emerged as an alternative owing to its low cost and shorter recovery times. We sought to retrospectively compare the procedural success rates and adverse events of these methods. METHODS: Patients were identified by querying our health system patient database and the departmental database of patients who underwent DPEJ. The patients were divided into 3 cohorts based on the procedure: DPEJ, lap-J, or open-J. Patient age and body mass index, procedural success rate, and adverse event rate were compared among the 3 groups. RESULTS: A total of 201 patients met inclusion criteria (65 DPEJ, 111 lap-J, and 25 open-J). Procedural success rates were similar among the 3 groups (DPEJ 96.9%, lap-J 99.1%, open-J 100%; P = .702). Rates of infection and bleeding were also similar among the 3 groups. There were no cases of GI perforation. Tube dysfunction for any reason that required complete removal or replacement within 90 days occurred more often in the surgical groups than in the DPEJ group (DPEJ 0%, lap-J 35.1%, open-J 40.0%; P < .001). This was driven largely by increased rates of tube clogging and tube dislodgement in the surgical groups. CONCLUSIONS: DPEJ is a safe and effective alternative to surgical jejunostomy in eligible patients and may be associated with decreased adverse event rates at 90 days.


Assuntos
Nutrição Enteral , Jejunostomia , Humanos , Jejunostomia/métodos , Jejunostomia/efeitos adversos , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Nutrição Enteral/métodos , Nutrição Enteral/instrumentação , Endoscopia Gastrointestinal/métodos , Endoscopia Gastrointestinal/efeitos adversos , Adulto , Laparoscopia/métodos , Resultado do Tratamento , Idoso de 80 Anos ou mais
16.
Gastrointest Endosc ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38431104

RESUMO

BACKGROUND AND AIMS: Direct endoscopic necrosectomy (DEN) is a recommended strategy for treatment of walled-off-necrosis (WON). DEN uses a variety of devices including the EndoRotor (Interscope, Inc.) debridement catheter. Recently, a 5.1 mm EndoRotor with increased chamber size and rate of tissue removal was introduced. The aim of this study was to assess the efficacy and safety of this device. METHODS: A multi-center cohort study was conducted at eight institutions including patients who underwent DEN with the 5.1 mm EndoRotor. The primary outcome was the number of DEN sessions needed for WON resolution. Secondary outcomes included the average percent reduction in solid WON debris and decrease in WON area per session, total time spent performing EndoRotor therapy for WON resolution, and adverse events. RESULTS: 64 procedures in 41 patients were included. For patients in which the 5.1 mm EndoRotor catheter was the sole therapeutic modality, an average of 1.6 DEN sessions resulted in WON resolution with an average cumulative time of 85.5 minutes. Of the 21 procedures with data regarding percent of solid debris, the average reduction was 85% +/- 23% per session. Of the 19 procedures with data regarding WON area, the mean area significantly decreased from 97.6 +/- 72.0 cm2 to 27.1 +/- 35.5 cm2 (p<0.001) per session. Adverse events included two intra-procedural LAMS dislodgements managed endoscopically and three perforations none of which were related to EndoRotor. Bleeding was reported in seven cases, none required embolic or surgical therapy and two required blood transfusions. CONCLUSIONS: This is the first multi-center retrospective study to investigate the efficacy and safety of the 5.1 mm EndoRotor catheter for WON. Results from this study showed an average of 1.6 DEN sessions were needed to achieve WON resolution with an 85% single session reduction in solid debris and a 70% single session decrease in WON area with minimal adverse events.

17.
Malar J ; 23(1): 103, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609987

RESUMO

BACKGROUND: The emergence of resistance to artemisinin-based combination therapy necessitates the search for new, more potent antiplasmodial compounds, including herbal remedies. The whole extract of Maytenus senegalensis has been scientifically investigated for potential biological activities both in vitro and in vivo, demonstrating strong antimalarial activity. However, there is a lack of data on the electrocardiographic effects of M. senegalensis in humans, which is a crucial aspect in the investigation of malaria treatment. Assessing the electrocardiographic effects of M. senegalensis is essential, as many anti-malarial drugs can inadvertently prolong the QT interval on electrocardiograms. Therefore, the study's objective was to evaluate the electrocardiographic effects of M. senegalensis in healthy adult volunteers. METHODS: This study is a secondary analysis of an open-label single-arm dose escalation. Twelve healthy eligible Tanzanian males, aged 18 to 45, were enrolled in four study dose groups. A single 12-lead electrocardiogram (ECG) was performed at baseline and on days 3, 7, 14, 28, and 56. RESULTS: No QTcF adverse events occurred with any drug dose. Only one volunteer who received the highest dose (800 mg) of M. senegalensis experienced a moderate transient change (△QTcF > 30 ms; specifically, the value was 37 ms) from baseline on day 28. There was no difference in maximum QTcF and maximum △QTcF between volunteers in all four study dose groups. CONCLUSIONS: A four-day regimen of 800 mg every 8 h of M. senegalensis did not impact the electrocardiographic parameters in healthy volunteers. This study suggests that M. senegalensis could be a valuable addition to malaria treatment, providing a safer alternative and potentially aiding in the battle against artemisinin-resistant malaria. The results of this study support both the traditional use and the modern therapeutic potential of M. senegalensis. They also set the stage for future research involving larger and more diverse populations to explore the safety profile of M. senegalensis in different demographic groups. This is especially important considering the potential use of M. senegalensis as a therapeutic agent and its widespread utilization as traditional medicine. Trial registration ClinicalTrials.gov, NCT04944966. Registered 30 June 2021-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04944966?term=kamaka&draw=2&rank=1.


Assuntos
Antimaláricos , Artemisininas , Malária , Maytenus , Adulto , Humanos , Masculino , Antimaláricos/farmacologia , Eletrocardiografia , Voluntários Saudáveis , Malária/tratamento farmacológico , Tanzânia , Voluntários , Adulto Jovem , Pessoa de Meia-Idade
18.
Analyst ; 149(12): 3433-3443, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38721993

RESUMO

A novel analysis technique of elements at ambient conditions has been developed. The technique is based on microwave-assisted laser-induced breakdown spectroscopy (MW-LIBS) applied to acoustically levitated samples. The technique has been demonstrated using three solid samples with different properties and compositions. These are ore containing multiple elements (OREAS 520), aluminium oxide (Al3O2) and gypsum (CaSO4·2H2O). The mass of samples was 21 mg, 23 mg, and 55 mg for gypsum, mineral ore, and Al3O2, respectively. Significant signal enhancements were recorded for a variety of elements, using microwave-assisted laser-induced breakdown spectroscopy and levitation (MW-LIBS-Levitation). The signal enhancement for Mn I (403.07 nm), Al I (396.13 nm) and Ca II (393.85 nm) was determined as 123, 46, and 63 times, respectively. Moreover, it was found that MW-LIBS-Levitation minimises the self-absorption of the Ca I (422.67 nm) and Na I (588.99 nm and 589.59 nm) spectral lines. In addition to the signal enhancements, the levitation process produces a spinning motion in the solids with an angular frequency of 7 Hz. This feature benefits laser-based analysis as a fresh sample is introduced at each laser pulse, eliminating the need for the usual mechanical devices. Based on the single-shot analysis, it was found that ∼80% of the laser pulses produced successful MW-LIBS-Levitation detection, confirming an impressive repeatability of the process. This contactless analytical technique can be applied in ambient pressure and temperature conditions with high sensitivity, which can benefit disciplines such as forensics science, isotope analysis, and medical analysis, where the sample availability is often diminutive.

19.
BMC Med Res Methodol ; 24(1): 82, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580928

RESUMO

BACKGROUND: This retrospective analysis aimed to comprehensively review the design and regulatory aspects of bioequivalence trials submitted to the Saudi Food and Drug Authority (SFDA) since 2017. METHODS: This was a retrospective, comprehensive analysis study. The Data extracted from the SFDA bioequivalence assessment reports were analyzed for reviewing the overall design and regulatory aspects of the successful bioequivalence trials, exploring the impact of the coefficient of variation of within-subject variability (CVw) on some design aspects, and providing an in-depth assessment of bioequivalence trial submissions that were deemed insufficient in demonstrating bioequivalence. RESULTS: A total of 590 bioequivalence trials were included of which 521 demonstrated bioequivalence (440 single active pharmaceutical ingredients [APIs] and 81 fixed combinations). Most of the successful trials were for cardiovascular drugs (84 out of 521 [16.1%]), and the 2 × 2 crossover design was used in 455 (87.3%) trials. The sample size tended to increase with the increase in the CVw in trials of single APIs. Biopharmaceutics Classification System Class II and IV drugs accounted for the majority of highly variable drugs (58 out of 82 [70.7%]) in the study. Most of the 51 rejected trials were rejected due to concerns related to the study center (n = 21 [41.2%]). CONCLUSION: This comprehensive analysis provides valuable insights into the regulatory and design aspects of bioequivalence trials and can inform future research and assist in identifying opportunities for improvement in conducting bioequivalence trials in Saudi Arabia.


Assuntos
Medicamentos Genéricos , Humanos , Equivalência Terapêutica , Medicamentos Genéricos/uso terapêutico , Arábia Saudita , Estudos Retrospectivos , Tamanho da Amostra
20.
Inorg Chem ; 63(17): 7725-7734, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38623051

RESUMO

Layered carbides are fascinating compounds due to their enormous structural and chemical diversity, as well as their potential to possess useful and tunable functional properties. Their preparation, however, is challenging and forces synthesis scientists to develop creative and innovative strategies to access high-quality materials. One unique compound among carbides is Mo2Ga2C. Its structure is related to the large and steadily growing family of 211 MAX phases that crystallize in a hexagonal structure (space group P63/mmc) with alternating layers of edge-sharing M6X octahedra and layers of the A-element. Mo2Ga2C also crystallizes in the same space group, with the difference that the A-element layer is occupied by two A-elements, here Ga, that sit right on top of each other (hence named "221" compound). Here, we propose that the Ga content in this compound is variable between 2:2, 2:1, and 2: ≤1 (and 2:0) Mo/Ga ratios. We demonstrate that one Ga layer can be selectively removed from Mo2Ga2C without jeopardizing the hexagonal P63/mmc structure. This is realized by chemical treatment of the 221 phase Mo2Ga2C with a Lewis acid, leading to the "conventional" 211 MAX phase Mo2GaC. Upon further reaction with CuCl2, more Ga is removed and replaced with Cu (instead of fully exfoliating into the Ga-free Mo2CTx MXene), leading to Mo2Ga1-xCuxC still crystallizing with space group P63/mmc, however, with a significantly larger c-lattice parameter. Furthermore, 211 Mo2GaC can be reacted with Ga to recover the initial 221 Mo2Ga2C. All three reaction pathways have not been reported previously and are supported by powder X-ray diffraction (PXRD), electron microscopy, X-ray spectroscopy, and density functional theory (DFT) calculations.

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