Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 62
Filtrar
1.
Arch Orthop Trauma Surg ; 144(2): 975-984, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38063881

RESUMO

INTRODUCTION: The optimal treatment of chronic scapholunate instability has yet to be established. Scapholunate ligament grafts are still far from being the ideal solution. We conducted an experimental study to evaluate whether flexion-opening wedge osteotomy of the distal radius improves misalignment and avoids rotatory subluxation of the scaphoid in a cadaveric model of static scapholunate dissociative instability. MATERIALS AND METHODS: Radiographic studies were performed on 15 cryopreserved specimens after recreating a model of scapholunate instability by division of the scapholunate interosseous ligament (SLIL) and secondary stabilizers, taking radiographs at baseline, after the instability model, and after distal radius osteotomy. Static and dynamic (under controlled tendon traction) anteroposterior and lateral views were obtained to measure the length (in mm) of the carpal scaphoid and scapholunate interval, scapholunate angle, radio-lunate angle, and palmar tilt of the distal joint surface of the radius and to measure the dorsal scaphoid translation by the concentric circles method. The Wilcoxon test was used for statistical comparisons. RESULTS: The scapholunate interval was significantly decreased after osteotomy in all static anteroposterior views and in all lateral views under tendon traction. Dorsal scaphoid translation was significantly reduced in static lateral view in extension and in dynamic lateral view under 5-pound flexor carpi radialis tendon tension controlled by a digital dynamometer. CONCLUSIONS: Flexion-addition osteotomy of the distal radius appears to improve carpal alignment parameters in a cadaveric model of static scapholunate instability, achieving similar values to those obtained before instability.


Assuntos
Instabilidade Articular , Osso Semilunar , Osso Escafoide , Humanos , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/cirurgia , Osso Semilunar/diagnóstico por imagem , Osso Semilunar/cirurgia , Osso Escafoide/diagnóstico por imagem , Osso Escafoide/cirurgia , Articulação do Punho/diagnóstico por imagem , Articulação do Punho/cirurgia , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/cirurgia , Osteotomia , Cadáver , Ligamentos Articulares/diagnóstico por imagem , Ligamentos Articulares/cirurgia
2.
Proc Natl Acad Sci U S A ; 117(34): 20785-20793, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32778592

RESUMO

Transfer RNA (tRNA) activity is tightly regulated to provide a physiological protein translation, and tRNA chemical modifications control its function in a complex with ribosomes and messenger RNAs (mRNAs). In this regard, the correct hypermodification of position G37 of phenylalanine-tRNA, adjacent to the anticodon, is critical to prevent ribosome frameshifting events. Here we report that the tRNA-yW Synthesizing Protein 2 (TYW2) undergoes promoter hypermethylation-associated transcriptional silencing in human cancer, particularly in colorectal tumors. The epigenetic loss of TYW2 induces guanosine hypomodification in phenylalanine-tRNA, an increase in -1 ribosome frameshift events, and down-regulation of transcripts by mRNA decay, such as of the key cancer gene ROBO1. Importantly, TYW2 epigenetic inactivation is linked to poor overall survival in patients with early-stage colorectal cancer, a finding that could be related to the observed acquisition of enhanced migration properties and epithelial-to-mesenchymal features in the colon cancer cells that harbor TYW2 DNA methylation-associated loss. These findings provide an illustrative example of how epigenetic changes can modify the epitranscriptome and further support a role for tRNA modifications in cancer biology.


Assuntos
Neoplasias do Colo/genética , Mudança da Fase de Leitura do Gene Ribossômico , RNA de Transferência/genética , Ribossomos/genética , tRNA Metiltransferases/deficiência , Adulto , Idoso , Anticódon/genética , Anticódon/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/enzimologia , Neoplasias do Colo/metabolismo , Ilhas de CpG , Epigênese Genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Conformação de Ácido Nucleico , Fenilalanina/genética , Fenilalanina/metabolismo , Regiões Promotoras Genéticas , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Transferência/metabolismo , Ribossomos/metabolismo , tRNA Metiltransferases/genética , tRNA Metiltransferases/metabolismo
3.
Plant Dis ; 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37721521

RESUMO

In Mexico, potato (Solanum tuberosum L.) is one of the most important vegetable crops for local consumption and industry. More than 1.8 million tons of potatoes are produced annually, of which the state of Sinaloa contributes with 21.5% (SIAP. 2022). In January 2020, potato plants (cv. FL1867) showing aerial stem rot symptoms were observed in a commercial field from the Santa Rosa Valley, in Northern Sinaloa with an incidence of 36%. Putative pectolytic bacteria showing pitting on crystal violet pectate (CVP) plates were restreaked and purified onto Nutritive Agar (NA) medium at 28°C. Four independent isolates were obtained (L25F-83, L25F-105, L25F-115, and L25F-125) from four symptomatic stems with biochemical and morphological characteristics related to Pectobacterium, such as catalase positive, oxidase negative, pectinolytic activity, Gram-negative and non-fluorescent in B-King medium. Bacterial gDNA was used for amplification and sequencing of two housekeeping genes (dnaX and leuS) (Portier et al. 2019). The nucleotide sequence identity between our isolates was 100% with both housekeeping genes (dnaX, OP376536-OP376539 and leuS, OP376540-OP376543). The BLASTn analysis of dnaX gene shared 98.98% and 99.19% identity with two soft-rot-causing bacterial strains NIBIO1006T (CP017481) and NIBIO1392 (CP017482) of Pectobacterium polaris, respectively; and with leuS gene shared 99.56% identity with P. polaris type strain NIBIO1006T. To further validate the identification, two strains, S5 (isolate L25F-105) and S6 (L25F-125), were selected for whole genome sequencing (WGS). The ANI values for closely related species were calculated using the Orthologous Average Nucleotide Identity (Ortho-ANI) Software Tool (OAT) (Lee et al. 2016). The Type (Strain) Genome Server (TYGS) was used for accurate genome-based taxonomy (https://tygs.dsmz.de) (Meier-Kolthoff et al. 2019). The genomes of P. polaris strains S5 (4811345 pb, GC=52%, AULSZ000000000) and S6 (4809754 pb, GC=52%, JAULTA000000000) revealed 96.86% and 96.07% Ortho-ANI and 73.6% and 66.5% dDDH with P. polaris type strain NIBIO1006T and P. parvum strain CFBP8630, respectively. The MLSA was performed on concatenated complete sequences of dnaX (OR470476, OR470477), leuS (OR470484, OR470485), recA (OR470488, OR470488), acnA (OR470474, OR470475), gapA (OR470478, OR470479), gyrA (OR470480, OR470481), icdA (OR470482, OR470483), proA (OR470486, OR470487), and rpoA genes (OR470490, OR470491). The consensus tree, constructed using the maximum likelihood method (MEGA 7.0), clustered strains S5 and S6 with P. polaris strains NIBIO1006T and NIBIO1392. The four isolates resulted pathogenic in tuber slices and potato seedlings (cv. Fianna) 24 and 72 h, respectively, after being inoculated with 30 µL bacterial suspension (1 X 108 CFU/ml) and incubated at 28 °C and 85% relative humidity. Bacterial colonies were reisolated from the affected tissue and identified with the same PCR primers as described above. Accordingly, P. polaris isolates S5 and S6, fulfill Koch's postulates for aerial stem rot of potato. To our knowledge, this is the first report of P. polaris causing aerial stem rot of potato in Mexico. This bacterium could be a significant threat to the local potato producers; therefore, an accurate and sensitive method of detection and epidemiological studies are needed to support an effective disease diagnosis and management program.

4.
PLoS Genet ; 13(3): e1006686, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28339467

RESUMO

Mucorales are a group of basal fungi that includes the casual agents of the human emerging disease mucormycosis. Recent studies revealed that these pathogens activate an RNAi-based pathway to rapidly generate drug-resistant epimutant strains when exposed to stressful compounds such as the antifungal drug FK506. To elucidate the molecular mechanism of this epimutation pathway, we performed a genetic analysis in Mucor circinelloides that revealed an inhibitory role for the non-canonical RdRP-dependent Dicer-independent silencing pathway, which is an RNAi-based mechanism involved in mRNA degradation that was recently identified. Thus, mutations that specifically block the mRNA degradation pathway, such as those in the genes r3b2 and rdrp3, enhance the production of drug resistant epimutants, similar to the phenotype previously described for mutation of the gene rdrp1. Our genetic analysis also revealed two new specific components of the epimutation pathway related to the quelling induced protein (qip) and a Sad-3-like helicase (rnhA), as mutations in these genes prevented formation of drug-resistant epimutants. Remarkably, drug-resistant epimutant production was notably increased in M. circinelloides f. circinelloides isolates from humans or other animal hosts. The host-pathogen interaction could be a stressful environment in which the phenotypic plasticity provided by the epimutant pathway might provide an advantage for these strains. These results evoke a model whereby balanced regulation of two different RNAi pathways is determined by the activation of the RNAi-dependent epimutant pathway under stress conditions, or its repression when the regular maintenance of the mRNA degradation pathway operates under non-stress conditions.


Assuntos
Mucor/genética , Mutação , Interferência de RNA , RNA Fúngico/genética , Sequência de Aminoácidos , Farmacorresistência Fúngica/efeitos dos fármacos , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Imunossupressores/farmacologia , Modelos Genéticos , Mucormicose/microbiologia , Estabilidade de RNA , RNA Fúngico/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/genética , Tacrolimo/farmacologia
5.
Rev Invest Clin ; 72(3): 165-177, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32584326

RESUMO

BACKGROUND: Regional information regarding the characteristics of patients with coronavirus disease (COVID)-19 is needed for a better understanding of the pandemic. OBJECTIVE: The objective of the study to describe the clinical features of COVID-19 patients diagnosed in a tertiary-care center in Mexico City and to assess differences according to the treatment setting (ambulatory vs. hospital) and to the need of intensive care (IC). METHODS: We conducted a prospective cohort, including consecutive patients with COVID-19 from February 26, 2020 to April 11, 2020. RESULTS: We identified 309 patients (140 inpatients and 169 outpatients). The median age was 43 years (interquartile range, 33-54), 59.2% men, and 18.6% healthcare workers (12.3% from our center). The median body mass index (BMI) was 29.00 kg/m2 and 39.6% had obesity. Compared to outpatients, inpatients were older, had comorbidities, cough, and dyspnea more frequently. Twenty-nine (20.7%) inpatients required treatment in the IC unit (ICU). History of diabetes (type 1 or 2) and abdominal pain were more common in ICU patients compared to non-ICU patients. ICU patients had higher BMIs, higher respiratory rates, and lower room-air capillary oxygen saturations. ICU patients showed a more severe inflammatory response as assessed by white blood cell count, neutrophil and platelet count, C-reactive protein, ferritin, procalcitonin, and albumin levels. By the end of the study period, 65 inpatients had been discharged because of improvement, 70 continued hospitalized, and five had died. CONCLUSIONS: Patients with comorbidities, either middle-age obese or elderly complaining of fever, cough, or dyspnea, were more likely to be admitted. At admission, patients with diabetes, high BMI, and clinical or laboratory findings consistent with a severe inflammatory state were more likely to require IC.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Dor Abdominal/epidemiologia , Adulto , Idoso , Assistência Ambulatorial , Biomarcadores/sangue , Índice de Massa Corporal , COVID-19 , Comorbidade , Infecções por Coronavirus/complicações , Infecções por Coronavirus/terapia , Cuidados Críticos , Dispneia/etiologia , Feminino , Gastroenteropatias/epidemiologia , Humanos , Pacientes Internados/estatística & dados numéricos , Masculino , México , Pessoa de Meia-Idade , Obesidade/epidemiologia , Pacientes Ambulatoriais/estatística & dados numéricos , Pneumonia Viral/complicações , Pneumonia Viral/terapia , SARS-CoV-2 , Índice de Gravidade de Doença , Centros de Atenção Terciária/estatística & dados numéricos , Resultado do Tratamento
6.
Acta Neuropathol ; 138(6): 1053-1074, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31428936

RESUMO

Tumors have aberrant proteomes that often do not match their corresponding transcriptome profiles. One possible cause of this discrepancy is the existence of aberrant RNA modification landscapes in the so-called epitranscriptome. Here, we report that human glioma cells undergo DNA methylation-associated epigenetic silencing of NSUN5, a candidate RNA methyltransferase for 5-methylcytosine. In this setting, NSUN5 exhibits tumor-suppressor characteristics in vivo glioma models. We also found that NSUN5 loss generates an unmethylated status at the C3782 position of 28S rRNA that drives an overall depletion of protein synthesis, and leads to the emergence of an adaptive translational program for survival under conditions of cellular stress. Interestingly, NSUN5 epigenetic inactivation also renders these gliomas sensitive to bioactivatable substrates of the stress-related enzyme NQO1. Most importantly, NSUN5 epigenetic inactivation is a hallmark of glioma patients with long-term survival for this otherwise devastating disease.


Assuntos
Neoplasias Encefálicas/metabolismo , Epigênese Genética , Glioma/metabolismo , Metiltransferases/metabolismo , Proteínas Musculares/metabolismo , Biossíntese de Proteínas/fisiologia , Ribossomos/metabolismo , Animais , Biomarcadores Tumorais , Linhagem Celular Tumoral , Metilação de DNA , Humanos , Metiltransferases/genética , Camundongos Nus , Proteínas Musculares/genética , Transplante de Neoplasias , RNA Ribossômico 28S
8.
J Am Geriatr Soc ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39360482

RESUMO

BACKGROUND: The purpose of this project was to measure satisfaction with virtual comprehensive geriatric assessments (CGA) among older Veterans (OVs). METHODS: The CGA involved five different healthcare providers and four one-hour VA Video Connect (VVC) calls. Using specific enrollment criteria, OVs were recruited in four cohorts separated by time. After completing the CGA, participants were asked to complete a 10-statement telephone questionnaire. Before analyses, responses to each statement were dichotomized as Agree (Agree/Strongly agree) or Do not Agree (Neutral/Disagree/Strongly Disagree). Descriptive statistics and Binomial generalized linear models (GLMs) were used to analyze the data. RESULTS: All 269 enrolled OVs completed all components of the CGA. This included 79, 57, 61, and 72 Veterans in cohorts 1 to 4, respectively. Their average age was 76.0 ± 5.9 years, and they were predominately white (82%), male (94%), and residents of rural settings (64%). Of the 236 (88%) OVs who completed the telephone survey, 57% indicated they were comfortable using VVC and 57% expressed willingness to use VVC again; 44% felt that VVC was easier than going to in-person visits. The OVs in Cohort 1 were more likely to agree with these statements than those in the remaining cohorts, especially Cohorts 2 and 4. Differences in demographics partially explained some of these findings. The majority (89% or higher) of survey participants agreed with the remaining seven survey statements indicating they were satisfied with the CGA program. CONCLUSION: OVs were very satisfied with their participation in a program of CGA, although not necessarily the mode of delivery. The percentage of participants who indicated discomfort using VVC for the CGA visits appeared to increase with time. Further work is needed to determine which OVs would be the best candidates to use VVC to complete all or part of a CGA.

9.
Blood Adv ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058976

RESUMO

Hematological toxicity is a common side effect of CAR-T therapies, particularly severe in relapsed/refractory multiple myeloma (MM) patients. In this study, we analyzed a cohort of 48 patients treated with BCMA CAR-T cells to characterize the kinetics of cytopenia, identify predictive factors and determine potential mechanism underlying these toxicities. The overall incidence of cytopenia was 95.7%, and grade>3 thrombocytopenia and neutropenia, one month after infusion, was observed in 57% and 53% of the patients, being still present after one year in 4 and 3 patients respectively. Presence of cytopenia at baseline and high peak inflammatory markers highly correlated with cytopenia persisting up to three months. To determine potential mechanisms underpinning cytopenias, we evaluated the paracrine effect of BCMA CAR-T cells on HSPCs differentiation using an ex-vivo myeloid differentiation model. Phenotypic analysis showed that supernatants from activated CAR-T cells (spCAR) halted HSPCs differentiation, promoting more immature phenotypes, with reduced expression of granulocytic, monocytic and erythroid markers, which could be prevented with a combination of IFNγ, TNFα/ß, TGFß, IL-6 and IL-17 inhibitors. Single-cell RNA-seq demonstrated upregulation of transcription factors associated with early stages of hematopoietic differentiation in the presence of spCAR (GATA2, RUNX1, CEBPA) and decreased activity of key regulons involved in neutrophil and monocytic maturation (ID2, MAFB). Our results suggest that CAR-T cell activation negatively influences hematopoietic differentiation through paracrine effects inducing HSPCs maturation arrest. Moreover, our study contributes to the understanding of severe cytopenia observed after CAR-T therapy in MM and provides potential treatments to prevent or decrease its severity.

10.
PLoS Pathog ; 7(6): e1002086, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21698218

RESUMO

Mucor circinelloides is a zygomycete fungus and an emerging opportunistic pathogen in immunocompromised patients, especially transplant recipients and in some cases otherwise healthy individuals. We have discovered a novel example of size dimorphism linked to virulence. M. circinelloides is a heterothallic fungus: (+) sex allele encodes SexP and (-) sex allele SexM, both of which are HMG domain protein sex determinants. M. circinelloides f. lusitanicus (Mcl) (-) mating type isolates produce larger asexual sporangiospores that are more virulent in the wax moth host compared to (+) isolates that produce smaller less virulent sporangiospores. The larger sporangiospores germinate inside and lyse macrophages, whereas the smaller sporangiospores do not. sexMΔ mutants are sterile and still produce larger virulent sporangiospores, suggesting that either the sex locus is not involved in virulence/spore size or the sexP allele plays an inhibitory role. Phylogenetic analysis supports that at least three extant subspecies populate the M. circinelloides complex in nature: Mcl, M. circinelloides f. griseocyanus, and M. circinelloides f. circinelloides (Mcc). Mcc was found to be more prevalent among clinical Mucor isolates, and more virulent than Mcl in a diabetic murine model in contrast to the wax moth host. The M. circinelloides sex locus encodes an HMG domain protein (SexP for plus and SexM for minus mating types) flanked by genes encoding triose phosphate transporter (TPT) and RNA helicase homologs. The borders of the sex locus between the three subspecies differ: the Mcg sex locus includes the promoters of both the TPT and the RNA helicase genes, whereas the Mcl and Mcc sex locus includes only the TPT gene promoter. Mating between subspecies was restricted compared to mating within subspecies. These findings demonstrate that spore size dimorphism is linked to virulence of M. circinelloides species and that plasticity of the sex locus and adaptations in pathogenicity have occurred during speciation of the M. circinelloides complex.


Assuntos
Mucor/patogenicidade , Esporos Fúngicos/citologia , Virulência/fisiologia , Processos de Crescimento Celular/genética , Processos de Crescimento Celular/fisiologia , Tamanho Celular , Individualidade , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mucor/citologia , Mucor/genética , Mucor/fisiologia , Tamanho das Organelas/fisiologia , Filogenia , Reprodução/genética , Reprodução/fisiologia , Esporângios/citologia , Esporos Fúngicos/genética , Esporos Fúngicos/fisiologia , Esporos Fúngicos/ultraestrutura , Virulência/genética
11.
Bioprocess Biosyst Eng ; 36(5): 531-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22926786

RESUMO

Lecanicillium lecanii, Verticillium chlamydosporium, V. fungicola var flavidum and Beauveria bassiana were evaluated on their growth with pure n-hexane, toluene and n-hexane:toluene 17:83 (v:v) mixture. Another set of treatments were conducted with colloidal chitin as additional carbon source. All the strains of Lecanicillium were able to grow using hydrocarbons with or without the addition of chitin, although the presence of hydrocarbons showed significant inhibition evidenced by measured biomass, radial growth and microscopic analyses. Degradation of n-hexane ranged within 43 and 62 % and it was higher than that with toluene. The strains L460, L157 and L2149, which presented the highest growth, were further selected for determinations of hydrocarbon consumptions in microcosms. Strain L157 showed the highest consumption of n-hexane (55.6 %) and toluene (52.9 %) as sole carbon source and it also displayed activities of endochitinases, N-acetylhexosaminidase and production of hydrophobins class I and II.


Assuntos
Amidoidrolases/biossíntese , Ascomicetos/crescimento & desenvolvimento , Quitinases/biossíntese , Proteínas Fúngicas/biossíntese , Hexanos/metabolismo , Tolueno/metabolismo
12.
Pain Manag ; 13(4): 219-232, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37218413

RESUMO

Background: Ecuador is facing increasing health-related suffering due to cancer; however, the distributed opioid analgesic in the country is below the global average. Aim: This study explores the access to cancer pain management (CPM) from the healthcare professionals' perspective in a middle-income country. Methods: Thirty problem-centered interviews with healthcare providers were conducted in six cancer facilities and were analyzed thematically. Results: Limited and unequal access to opioid analgesics was reported. Structural weaknesses of the healthcare system restrain access for the poorest, at the primary care level, and for people living in remote areas. The lack of education among the healthcare personnel, patients, and society was identified as the main barrier. Conclusion: Access barriers were interrelated; therefore multisectoral strategies must be considered to improve access to CPM.


The number of patients with cancer in Ecuador is growing. It is known that people with a cancer diagnosis often experience severe pain, which requires opioid analgesics. In this study, we explore the opinion of healthcare providers regarding access to opioid analgesics to alleviate cancer pain in Ecuador. We interviewed 30 healthcare professionals working at six cancer centers in different cities, who deal daily with patients with a cancer diagnosis. We found that it is difficult for cancer patients in the country to access adequate pain therapy and this generates avoidable severe health-related suffering. The structure of the healthcare system makes it difficult to be supplied with the medication they need. That is worst for the country's poor and people in rural areas. The main problem is the lack of knowledge on the subject among health workers, patients and society. We conclude that the obstacles in providing patients access to cancer pain relief lie in different areas, including the healthcare system, the healthcare professionals and the patients and society, all of which are interrelated. All areas must work together to improve the situation.


Assuntos
Neoplasias , Manejo da Dor , Humanos , Equador , Pessoal de Saúde , Analgésicos Opioides/uso terapêutico , Neoplasias/complicações
13.
J Xenobiot ; 13(1): 90-101, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36810433

RESUMO

In this work, a stability study of dispersions of graphene oxide and graphene oxide functionalized with polyethylene glycol (PEG) in the presence of bovine serum albumin is carried out. First, a structural characterization of these nanomaterials is performed by scanning electron microscopy, atomic force microscopy, and ultraviolet visible spectroscopy, comparing the starting nanomaterials with the nanomaterials in contact with the biological material, i.e., bovine fetal serum. The different experiments were performed at different concentrations of nanomaterial (0.125-0.5 mg/mL) and BSA (0.01-0.04 mg/mL), at different incubation times (5-360 min), with and without PEG, and at different temperatures (25-40 °C). The SEM results show that BSA is adsorbed on the surface of the graphene oxide nanomaterial. Using UV-Vis spectrophotometry, the characteristic absorption peaks of BSA are observed at 210 and 280 nm, corroborating that the protein has been adsorbed. When the time increases, the BSA protein can be detached from the nanomaterial due to a desorption process. The stability of the dispersions is reached at a pH between 7 and 9. The dispersions behave like a Newtonian fluid with viscosity values between 1.1 and 1.5 mPa·s at a temperature range of 25 to 40 °C. The viscosity values decrease as the temperature increases.

14.
Plants (Basel) ; 12(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36903899

RESUMO

Huanglongbing (HLB) is one of the most destructive diseases threatening citriculture worldwide. This disease has been associated with α-proteobacteria species, namely Candidatus Liberibacter. Due to the unculturable nature of the causal agent, it has been difficult to mitigate the disease, and nowadays a cure is not available. MicroRNAs (miRNAs) are key regulators of gene expression, playing an essential role in abiotic and biotic stress in plants including antibacterial responses. However, knowledge derived from non-model systems including Candidatus Liberibacter asiaticus (CLas)-citrus pathosystem remains largely unknown. In this study, small RNA profiles from Mexican lime (Citrus aurantifolia) plants infected with CLas at asymptomatic and symptomatic stages were generated by sRNA-Seq, and miRNAs were obtained with ShortStack software. A total of 46 miRNAs, including 29 known miRNAs and 17 novel miRNAs, were identified in Mexican lime. Among them, six miRNAs were deregulated in the asymptomatic stage, highlighting the up regulation of two new miRNAs. Meanwhile, eight miRNAs were differentially expressed in the symptomatic stage of the disease. The target genes of miRNAs were related to protein modification, transcription factors, and enzyme-coding genes. Our results provide new insights into miRNA-mediated regulation in C. aurantifolia in response to CLas infection. This information will be useful to understand molecular mechanisms behind the defense and pathogenesis of HLB.

15.
Front Immunol ; 14: 1270843, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795087

RESUMO

Despite the potential of CAR-T therapies for hematological malignancies, their efficacy in patients with relapse and refractory Acute Myeloid Leukemia has been limited. The aim of our study has been to develop and manufacture a CAR-T cell product that addresses some of the current limitations. We initially compared the phenotype of T cells from AML patients and healthy young and elderly controls. This analysis showed that T cells from AML patients displayed a predominantly effector phenotype, with increased expression of activation (CD69 and HLA-DR) and exhaustion markers (PD1 and LAG3), in contrast to the enriched memory phenotype observed in healthy donors. This differentiated and more exhausted phenotype was also observed, and corroborated by transcriptomic analyses, in CAR-T cells from AML patients engineered with an optimized CAR construct targeting CD33, resulting in a decreased in vivo antitumoral efficacy evaluated in xenograft AML models. To overcome some of these limitations we have combined CRISPR-based genome editing technologies with virus-free gene-transfer strategies using Sleeping Beauty transposons, to generate CAR-T cells depleted of HLA-I and TCR complexes (HLA-IKO/TCRKO CAR-T cells) for allogeneic approaches. Our optimized protocol allows one-step generation of edited CAR-T cells that show a similar phenotypic profile to non-edited CAR-T cells, with equivalent in vitro and in vivo antitumoral efficacy. Moreover, genomic analysis of edited CAR-T cells revealed a safe integration profile of the vector, with no preferences for specific genomic regions, with highly specific editing of the HLA-I and TCR, without significant off-target sites. Finally, the production of edited CAR-T cells at a larger scale allowed the generation and selection of enough HLA-IKO/TCRKO CAR-T cells that would be compatible with clinical applications. In summary, our results demonstrate that CAR-T cells from AML patients, although functional, present phenotypic and functional features that could compromise their antitumoral efficacy, compared to CAR-T cells from healthy donors. The combination of CRISPR technologies with transposon-based delivery strategies allows the generation of HLA-IKO/TCRKO CAR-T cells, compatible with allogeneic approaches, that would represent a promising option for AML treatment.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Animais , Humanos , Idoso , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/metabolismo , Imunoterapia Adotiva/métodos , Modelos Animais de Doenças
16.
Nanomaterials (Basel) ; 12(4)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35215011

RESUMO

In this work, we prepared a series of N-functionalized carbon nanotubes by means of a process of acylation-amidation of commercial multiwall carbon nanotubes that were previously pre-oxidized with nitric acid. Three different amines, butylamine, N,N-dimethyl ethylenediamine, and ethylenediamine, were used in the process. The characterization of samples by several techniques probed the incorporation of nitrogen atoms to the carbon nanotubes, especially in the case of ethylenediamine. The solids were tested as catalysts in the synthesis of N-1-heptenyl-2-pyrrolidinone, included in the group of a γ-lactams, compounds that show important biological properties. The most active catalyst was that prepared with butylamine, which exhibited the highest SBET and Vpore values and contained an amount of nitrogen that was intermediate between that of the other two catalysts. A yield of 60% to N-1-heptenyl-2-pyrrolidinone was achieved after 3 h at 120 °C under free-solvent conditions. This catalyst could be used in four consecutive cycles without significant activity loss.

17.
Ecancermedicalscience ; 16: 1436, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36200009

RESUMO

The ecancer 'Choosing Wisely' conference was held for the first time in Latin America in Santa Cruz, Bolivia. The event had more than 150 registered attendees in addition to 22 speakers from different countries and different specialities in the field of oncology, who presented topics on prevention, oncological surgery, clinical oncology and palliative care, in order to demonstrate the current evidence of how to approach a patient in daily clinical practice based on the human resources, materials and drugs available, trying to offer the maximum benefit to the patient based on current scientific evidence. In addition to addressing issues of vital importance in breast cancer, during the 2 days of the event, updated information generated in recent years was presented, the results of which will change clinical practice. All the experts were in favour of developing strategies and methods that help us to properly select treatments to optimise resources and reduce the economic toxicity of the most modern and current treatments. This conference was an event of vital importance because it was the first face-to-face event for ecancer and the physicians after difficult years due to COVID-19.

18.
Mol Ther Methods Clin Dev ; 25: 137-146, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35402636

RESUMO

Genome-editing strategies, especially CRISPR-Cas9 systems, have substantially increased the efficiency of innovative therapeutic approaches for monogenic diseases such as primary hyperoxalurias (PHs). We have previously demonstrated that inhibition of glycolate oxidase using CRISPR-Cas9 systems represents a promising therapeutic option for PH type I (PH1). Here, we extended our work evaluating the efficacy of liver-specific inhibition of lactate dehydrogenase (LDH), a key enzyme responsible for converting glyoxylate to oxalate; this strategy would not be limited to PH1, being applicable to other PH subtypes. In this work, we demonstrate a liver-specific inhibition of LDH that resulted in a drastic reduction of LDH levels in the liver of PH1 and PH3 mice after a single-dose delivery of AAV8 vectors expressing the CRISPR-Cas9 system, resulting in reduced urine oxalate levels and kidney damage without signs of toxicity. Deep sequencing analysis revealed that this approach was safe and specific, with no off-targets detected in the liver of treated animals and no on-target/off-tissue events. Altogether, our data provide evidence that in vivo genome editing using CRISPR-Cas9 systems would represent a valuable tool for improved therapeutic approaches for PH.

19.
Commun Biol ; 5(1): 351, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35414121

RESUMO

Single-cell RNA-Sequencing has the potential to provide deep biological insights by revealing complex regulatory interactions across diverse cell phenotypes at single-cell resolution. However, current single-cell gene regulatory network inference methods produce a single regulatory network per input dataset, limiting their capability to uncover complex regulatory relationships across related cell phenotypes. We present SimiC, a single-cell gene regulatory inference framework that overcomes this limitation by jointly inferring distinct, but related, gene regulatory dynamics per phenotype. We show that SimiC uncovers key regulatory dynamics missed by previously proposed methods across a range of systems, both model and non-model alike. In particular, SimiC was able to uncover CAR T cell dynamics after tumor recognition and key regulatory patterns on a regenerating liver, and was able to implicate glial cells in the generation of distinct behavioral states in honeybees. SimiC hence establishes a new approach to quantitating regulatory architectures between distinct cellular phenotypes, with far-reaching implications for systems biology.


Assuntos
Redes Reguladoras de Genes , Neoplasias , Animais , Abelhas , Regulação da Expressão Gênica , Fenótipo , Biologia de Sistemas
20.
Materials (Basel) ; 15(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35629621

RESUMO

Carbon nanomaterials have received increased attention in the last few years due to their potential applications in several areas. In medicine, for example, these nanomaterials could be used as contrast agents, drug transporters, and tissue regenerators or in gene therapy. This makes it necessary to know the behavior of carbon nanomaterials in biological media to assure good fluidity and the absence of deleterious effects on human health. In this work, the rheological characterization of different graphene nanomaterials in fetal bovine serum and other fluids, such as bovine serum albumin and water, is studied using rotational and microfluidic chip rheometry. Graphene oxide, graphene nanoplatelets, and expanded graphene oxide at concentrations between 1 and 3 mg/mL and temperatures in the 25-40 °C range were used. The suspensions were also characterized by transmission and scanning electron microscopy and atomic force microscopy, and the results show a high tendency to aggregation and reveals that there is a protein-nanomaterial interaction. Although rotational rheometry is customarily used, it cannot provide reliable measurements in low viscosity samples, showing an apparent shear thickening, whereas capillary viscometers need transparent samples; therefore, microfluidic technology appears to be a suitable method to measure low viscosity, non-transparent Newtonian fluids, as it is able to determine small variations in viscosity. No significant changes in viscosity are found within the solid concentration range studied but it decreases between 1.1 and 0.6 mPa·s when the temperature raises from 25 to 40 °C.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa