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1.
Immunity ; 57(8): 1893-1907.e6, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39096910

RESUMO

Naive CD4+ T cells in specific pathogen-free (SPF) mice are characterized by transcriptional heterogeneity and subpopulations distinguished by the expression of quiescence, the extracellular matrix (ECM) and cytoskeleton, type I interferon (IFN-I) response, memory-like, and T cell receptor (TCR) activation genes. We demonstrate that this constitutive heterogeneity, including the presence of the IFN-I response cluster, is commensal independent insofar as being identical in germ-free and SPF mice. By contrast, Nippostrongylus brasiliensis infection altered this constitutive heterogeneity. Naive T cell-intrinsic transcriptional changes acquired during helminth infection correlated with and accounted for decreased immunization response to an unrelated antigen. These compositional and functional changes were dependent variables of helminth infection, as they disappeared at the established time point of its clearance in mice. Collectively, our results indicate that the naive T cell pool is subject to dynamic transcriptional changes in response to certain environmental cues, which in turn permutes the magnitude of the immune response.


Assuntos
Linfócitos T CD4-Positivos , Nippostrongylus , Animais , Camundongos , Linfócitos T CD4-Positivos/imunologia , Nippostrongylus/imunologia , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologia , Organismos Livres de Patógenos Específicos , Transcrição Gênica , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Helmintíase/imunologia , Interferon Tipo I/metabolismo , Interferon Tipo I/imunologia , Camundongos Endogâmicos C57BL , Ativação Linfocitária/imunologia
2.
Cell ; 167(4): 1111-1124.e13, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27814508

RESUMO

Differences in susceptibility to immune-mediated diseases are determined by variability in immune responses. In three studies within the Human Functional Genomics Project, we assessed the effect of environmental and non-genetic host factors of the genetic make-up of the host and of the intestinal microbiome on the cytokine responses in humans. We analyzed the association of these factors with circulating mediators and with six cytokines after stimulation with 19 bacterial, fungal, viral, and non-microbial metabolic stimuli in 534 healthy subjects. In this first study, we show a strong impact of non-genetic host factors (e.g., age and gender) on cytokine production and circulating mediators. Additionally, annual seasonality is found to be an important environmental factor influencing cytokine production. Alpha-1-antitrypsin concentrations partially mediate the seasonality of cytokine responses, whereas the effect of vitamin D levels is limited. The complete dataset has been made publicly available as a comprehensive resource for future studies. PAPERCLIP.


Assuntos
Citocinas/genética , Citocinas/imunologia , Interação Gene-Ambiente , Adolescente , Adulto , Idoso , Envelhecimento , Animais , Artrite/imunologia , Sangue/imunologia , Índice de Massa Corporal , Feminino , Projeto Genoma Humano , Humanos , Infecções/imunologia , Infecções/microbiologia , Infecções/virologia , Inflamação/imunologia , Inflamação/microbiologia , Leucócitos Mononucleares/imunologia , Macrófagos/imunologia , Masculino , Camundongos , Pessoa de Meia-Idade , Estações do Ano , Caracteres Sexuais
3.
PLoS Pathog ; 20(7): e1012257, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38950082

RESUMO

An important aspect of how viruses spread and infect is the viral burst size, or the number of new viruses produced by each infected cell. Surprisingly, this value remains poorly characterized for influenza A virus (IAV), commonly known as the flu. In this study, we screened tens of thousands of cells using a microfluidic method called droplet quantitative PCR (dqPCR). The high-throughput capability of dqPCR enabled the measurement of a large population of infected cells producing progeny virus. By measuring the fully assembled and successfully released viruses from these infected cells, we discover that the viral burst sizes for both the seasonal H3N2 and the 2009 pandemic H1N1 strains vary significantly, with H3N2 ranging from 101 to 104 viruses per cell, and H1N1 ranging from 101 to 103 viruses per cell. Some infected cells produce average numbers of new viruses, while others generate extensive number of viruses. In fact, we find that only 10% of the single-cell infections are responsible for creating a significant portion of all the viruses. This small fraction produced approximately 60% of new viruses for H3N2 and 40% for H1N1. On average, each infected cell of the H3N2 flu strain produced 709 new viruses, whereas for H1N1, each infected cell produced 358 viruses. This novel method reveals insights into the flu virus and can lead to improved strategies for managing and preventing the spread of viruses.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Influenza Humana , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Análise de Célula Única/métodos , Animais , Células Madin Darby de Rim Canino , Vírus da Influenza A/genética , Cães , Replicação Viral
4.
Circulation ; 149(10): 747-759, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-37883784

RESUMO

BACKGROUND: The randomized, sham-controlled RADIANCE-HTN (A Study of the Recor Medical Paradise System in Clinical Hypertension) SOLO, RADIANCE-HTN TRIO, and RADIANCE II (A Study of the Recor Medical Paradise System in Stage II Hypertension) trials independently met their primary end point of a greater reduction in daytime ambulatory systolic blood pressure (SBP) 2 months after ultrasound renal denervation (uRDN) in patients with hypertension. To characterize the longer-term effectiveness and safety of uRDN versus sham at 6 months, after the blinded addition of antihypertensive treatments (AHTs), we pooled individual patient data across these 3 similarly designed trials. METHODS: Patients with mild to moderate hypertension who were not on AHT or with hypertension resistant to a standardized combination triple AHT were randomized to uRDN (n=293) versus sham (n=213); they were to remain off of added AHT throughout 2 months of follow-up unless specified blood pressure (BP) criteria were exceeded. In each trial, if monthly home BP was ≥135/85 mm Hg from 2 to 5 months, standardized AHT was sequentially added to target home BP <135/85 mm Hg under blinding to initial treatment assignment. Six-month outcomes included baseline- and AHT-adjusted change in daytime ambulatory, home, and office SBP; change in AHT; and safety. Linear mixed regression models using all BP measurements and change in AHT from baseline through 6 months were used. RESULTS: Patients (70% men) were 54.1±9.3 years of age with a baseline daytime ambulatory/home/office SBP of 150.5±9.8/151.0±12.4/155.5±14.4 mm Hg, respectively. From 2 to 6 months, BP decreased in both groups with AHT titration, but fewer uRDN patients were prescribed AHT (P=0.004), and fewer additional AHT were prescribed to uRDN patients versus sham patients (P=0.001). Whereas the unadjusted between-group difference in daytime ambulatory SBP was similar at 6 months, the baseline and medication-adjusted between-group difference at 6 months was -3.0 mm Hg (95% CI, -5.7, -0.2; P=0.033), in favor of uRDN+AHT. For home and office SBP, the adjusted between-group differences in favor of uRDN+AHT over 6 months were -5.4 mm Hg (-6.8, -4.0; P<0.001) and -5.2 mm Hg (-7.1, -3.3; P<0.001), respectively. There was no heterogeneity between trials. Safety outcomes were few and did not differ between groups. CONCLUSIONS: This individual patient-data analysis of 506 patients included in the RADIANCE trials demonstrates the maintenance of BP-lowering efficacy of uRDN versus sham at 6 months, with fewer added AHTs. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT02649426 and NCT03614260.


Assuntos
Hipertensão , Artéria Renal , Feminino , Humanos , Masculino , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Monitorização Ambulatorial da Pressão Arterial , Denervação/efeitos adversos , Denervação/métodos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Rim , Artéria Renal/diagnóstico por imagem , Simpatectomia/métodos , Resultado do Tratamento , Pessoa de Meia-Idade
5.
Ann Intern Med ; 177(2): 165-176, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38190711

RESUMO

BACKGROUND: The efficacy of the BNT162b2 vaccine in pediatrics was assessed by randomized trials before the Omicron variant's emergence. The long-term durability of vaccine protection in this population during the Omicron period remains limited. OBJECTIVE: To assess the effectiveness of BNT162b2 in preventing infection and severe diseases with various strains of the SARS-CoV-2 virus in previously uninfected children and adolescents. DESIGN: Comparative effectiveness research accounting for underreported vaccination in 3 study cohorts: adolescents (12 to 20 years) during the Delta phase and children (5 to 11 years) and adolescents (12 to 20 years) during the Omicron phase. SETTING: A national collaboration of pediatric health systems (PEDSnet). PARTICIPANTS: 77 392 adolescents (45 007 vaccinated) during the Delta phase and 111 539 children (50 398 vaccinated) and 56 080 adolescents (21 180 vaccinated) during the Omicron phase. INTERVENTION: First dose of the BNT162b2 vaccine versus no receipt of COVID-19 vaccine. MEASUREMENTS: Outcomes of interest include documented infection, COVID-19 illness severity, admission to an intensive care unit (ICU), and cardiac complications. The effectiveness was reported as (1-relative risk)*100, with confounders balanced via propensity score stratification. RESULTS: During the Delta period, the estimated effectiveness of the BNT162b2 vaccine was 98.4% (95% CI, 98.1% to 98.7%) against documented infection among adolescents, with no statistically significant waning after receipt of the first dose. An analysis of cardiac complications did not suggest a statistically significant difference between vaccinated and unvaccinated groups. During the Omicron period, the effectiveness against documented infection among children was estimated to be 74.3% (CI, 72.2% to 76.2%). Higher levels of effectiveness were seen against moderate or severe COVID-19 (75.5% [CI, 69.0% to 81.0%]) and ICU admission with COVID-19 (84.9% [CI, 64.8% to 93.5%]). Among adolescents, the effectiveness against documented Omicron infection was 85.5% (CI, 83.8% to 87.1%), with 84.8% (CI, 77.3% to 89.9%) against moderate or severe COVID-19, and 91.5% (CI, 69.5% to 97.6%) against ICU admission with COVID-19. The effectiveness of the BNT162b2 vaccine against the Omicron variant declined 4 months after the first dose and then stabilized. The analysis showed a lower risk for cardiac complications in the vaccinated group during the Omicron variant period. LIMITATION: Observational study design and potentially undocumented infection. CONCLUSION: This study suggests that BNT162b2 was effective for various COVID-19-related outcomes in children and adolescents during the Delta and Omicron periods, and there is some evidence of waning effectiveness over time. PRIMARY FUNDING SOURCE: National Institutes of Health.


Assuntos
Vacina BNT162 , COVID-19 , Estados Unidos , Humanos , Adolescente , Criança , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Pesquisa Comparativa da Efetividade , Hospitalização
6.
J Infect Dis ; 229(1): 137-146, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-37675756

RESUMO

BACKGROUND: Mucosal antibodies play a critical role in preventing SARS-CoV-2 infections or reinfections by blocking the interaction of the receptor-binding domain (RBD) with the angiotensin-converting enzyme 2 (ACE2) receptor on the cell surface. In this study, we investigated the difference between the mucosal antibody response after primary infection and vaccination. METHODS: We assessed longitudinal changes in the quantity and capacity of nasal antibodies to neutralize the interaction of RBD with the ACE2 receptor using the spike protein and RBD from ancestral SARS-CoV-2 (Wuhan-Hu-1), as well as the RBD from the Delta and Omicron variants. RESULTS: Significantly higher mucosal IgA concentrations were detected postinfection vs postvaccination, while vaccination induced higher IgG concentrations. However, ACE2-inhibiting activity did not differ between the cohorts. Regarding whether IgA or IgG drove ACE2 inhibition, infection-induced binding inhibition was driven by both isotypes, while postvaccination binding inhibition was mainly driven by IgG. CONCLUSIONS: Our study provides new insights into the relationship between antibody isotypes and neutralization by using a sensitive and high-throughput ACE2 binding inhibition assay. Key differences are highlighted between vaccination and infection at the mucosal level, showing that despite differences in the response quantity, postinfection and postvaccination ACE2 binding inhibition capacity did not differ.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Enzima de Conversão de Angiotensina 2 , COVID-19/prevenção & controle , Vacinação , Imunoglobulina A , Imunoglobulina G , Glicoproteína da Espícula de Coronavírus , Ligação Proteica
7.
Biophys J ; 123(16): 2594-2603, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38937973

RESUMO

Cytochromes c'-α are nitric oxide (NO)-binding heme proteins derived from bacteria that can thrive in a wide range of temperature environments. Studies of mesophilic Alcaligenes xylosoxidans cytochrome c'-α (AxCP-α) have revealed an unusual NO-binding mechanism involving both heme faces, in which NO first binds to form a distal hexa-coordinate Fe(II)-NO (6cNO) intermediate and then displaces the proximal His to form a proximal penta-coordinate Fe(II)-NO (5cNO) final product. Here, we characterize a thermally stable cytochrome c'-α from thermophilic Hydrogenophilus thermoluteolus (PhCP-α) to understand how protein thermal stability affects NO binding. Electron paramagnetic and resonance Raman spectroscopies reveal the formation of a PhCP-α 5cNO product, with time-resolved (stopped-flow) UV-vis absorbance indicating the involvement of a 6cNO intermediate. Relative to AxCP-α, the rates of 6cNO and 5cNO formation in PhCP-α are ∼11- and ∼13-fold lower, respectively. Notably, x-ray crystal structures of PhCP-α in the presence and absence of NO suggest that the sluggish formation of the proximal 5cNO product results from conformational rigidity: the Arg-132 residue (adjacent to the proximal His ligand) is held in place by a salt bridge between Arg-75 and Glu-135 (an interaction not present in AxCP-α or a psychrophilic counterpart). Overall, our data provide fresh insights into structural factors controlling NO binding in heme proteins, including 5cNO complexes relevant to eukaryotic NO sensors.


Assuntos
Citocromos c' , Óxido Nítrico , Ligação Proteica , Óxido Nítrico/metabolismo , Óxido Nítrico/química , Citocromos c'/química , Citocromos c'/metabolismo , Conformação Proteica , Hydrogenophilaceae/enzimologia , Hydrogenophilaceae/metabolismo , Hydrogenophilaceae/química , Temperatura , Modelos Moleculares , Cinética
8.
J Biol Chem ; 299(6): 104742, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37100286

RESUMO

The structural basis by which gas-binding heme proteins control their interactions with NO, CO, and O2 is fundamental to enzymology, biotechnology, and human health. Cytochromes c' (cyts c') are a group of putative NO-binding heme proteins that fall into two families: the well-characterized four alpha helix bundle fold (cyts c'-α) and an unrelated family with a large beta-sheet fold (cyts c'-ß) resembling that of cytochromes P460. A recent structure of cyt c'-ß from Methylococcus capsulatus Bath revealed two heme pocket phenylalanine residues (Phe 32 and Phe 61) positioned near the distal gas-binding site. This feature, dubbed the "Phe cap," is highly conserved within the sequences of other cyts c'-ß but is absent in their close homologs, the hydroxylamine-oxidizing cytochromes P460, although some do contain a single Phe residue. Here, we report an integrated structural, spectroscopic, and kinetic characterization of cyt c'-ß from Methylococcus capsulatus Bath complexes with diatomic gases, focusing on the interaction of the Phe cap with NO and CO. Significantly, crystallographic and resonance Raman data show that orientation of the electron-rich aromatic ring face of Phe 32 toward distally bound NO or CO is associated with weakened backbonding and higher off rates. Moreover, we propose that an aromatic quadrupole also contributes to the unusually weak backbonding reported for some heme-based gas sensors, including the mammalian NO sensor, soluble guanylate cyclase. Collectively, this study sheds light on the influence of highly conserved distal Phe residues on heme-gas complexes of cytochrome c'-ß, including the potential for aromatic quadrupoles to modulate NO and CO binding in other heme proteins.


Assuntos
Citocromos c' , Methylococcus capsulatus , Humanos , Citocromos c'/química , Gases , Heme/metabolismo , Hemeproteínas/genética , Hemeproteínas/metabolismo , Methylococcus capsulatus/química
9.
Am J Transplant ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38723867

RESUMO

Minimally invasive donor hepatectomy is an emerging surgical technique in living donor liver transplantation (LDLT). We examined outcomes across open, laparoscopic, and robotic LDLT using a prospective registry. We analyzed 3448 cases (1724 donor-recipient pairs) from January 2011 to March 2023 (NCT06062706). Among donors, 520 (30%) were female. Adult-to-adult LDLT comprised 1061 (62%) cases. A total of 646 (37%) of the donors underwent open, 165 (10%) laparoscopic, and 913 (53%) robotic hepatectomies. Primary outcomes: donor overall morbidity was 4% (35/903) for robotic, 8% (13/165) laparoscopic, and 16% (106/646) open (P < .001) procedures. Pediatric and adult recipient mortality was similar among the 3 donor hepatectomy approaches: robotic 1.5% and 7.0%, compared with 2.3% and 8.3% laparoscopic, and 1.6% and 5.5% for open donor surgery, respectively (P = .802, P = .564). Secondary outcomes: pediatric and adult recipients major morbidity after robotic hepatectomy was 15% and 23%, compared with 25% and 44% for laparoscopic surgery and 19% and 31% for open surgery, respectively (P = .033, P < .001). Graft and recipient 5-year survival were 90% and 93% for pediatrics and 79% and 80% for adults, respectively. In conclusion, robotic LDLT was associated with superior outcomes when compared with the laparoscopic and open approaches. Both donors and, for the first time reported, recipients benefitted from lower morbidity rates in robotic surgery, emphasizing its potential for further advancing this field.

10.
Ann Surg ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056178

RESUMO

OBJECTIVE: To evaluate the impact of robotic techniques on organ transplantation outcomes. SUMMARY BACKGROUND DATA: The evolution of organ transplantation is becoming influenced by the adoption of minimally invasive techniques, transitioning from laparoscopic to robotic methods. Robotic surgery has emerged as a significant advancement, providing superior precision and outcomes compared to traditional approaches. METHODS: This perspective includes a systematic review of the literature, original data from a high-volume center, as well as an international survey focusing on perceptions related to robotic versus laparoscopic and open approaches. RESULTS: The systematic review and meta-analysis revealed lower morbidity with robotic donor nephrectomy, recipient kidney transplant and donor hepatectomy. Our center's experience, with over 3,000 minimally invasive transplant procedures (kidney, liver, donor, and recipient), supports the superiority of Robotic Transplant Surgery (RTS). The global survey confirms this shift, revealing a preference for robotic approaches due to their reduced morbidity, despite challenges such as access to the robotic system and cost. CONCLUSION: This comprehensive overview including a systematic review, original data, and perceptions derived from the international survey demonstrate the superiority of Robotic Transplant Surgery (RTS) across a range of organ transplantations, for both donors and recipients. The future of RTS depends on the efforts of the surgical community in addressing challenges such as economic implications, the need for specialized surgical training for numerous surgeons, as well as wide access to robotic systems worldwide.

11.
Ann Surg ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39109444

RESUMO

OBJECTIVE: This study aimed to assess short-term biliary outcomes in adult living donor liver transplants using right grafts, comparing robotic surgery with real-time indocyanine green fluorescence cholangiography (ICG-CA) for optimal hilar plate transection, against the conventional open approach. SUMMARY BACKGROUND DATA: Determining the optimal transection plane through the hilar plate is crucial in donor hepatectomies, impacting outcomes significantly. PATIENTS AND METHODS: From 2011 to 2023, a total of 839 right graft living donor hepatectomies were performed, with 414 (49%) performed via the open approach and 425 (51%) utilizing the robotic platform. RESULTS: The MRCP predictions correlated moderately with the actual count of graft ducts (r=0.57,P<0.001) Out of all 839 right donor hepatectomies, 321 (44%) were single duct grafts, of which 193/425 (49%) were retrieved with the robotic while 128/414 (38%) were with the open approach (OR 1.58, 95% CI 1.16-2.14),P=0.003). Overall, 50 (6%) of the donors developed a biliary complication during hospital stay, of whom 38 (9%) were grafts retrieved with the open, while 13 (3%) with the robotic approach (OR 0.31, 95% CI 0.15-0.61,P<0.001). Similarly, 63 (15%) of the adult recipients developed a biliary complication of any severity when grafts were retrieved with the open approach compared to 35 (8%) with the robotic approach (OR 0.50, 95% CI 0.31-0.79),P=0.002). CONCLUSION: The robotic platform with integrated real-time ICG-CA during right donor hepatectomy offers improved safety for the donor by accurately addressing the right hilar corridor, resulting in fewer graft ducts, and fewer complications of the donor and recipient when compared to the standard open approach.

12.
Nat Mater ; 22(11): 1394-1400, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37749314

RESUMO

Our lives cannot be imagined without polymer networks, which range widely, from synthetic rubber to biological tissues. Their properties-elasticity, strain-stiffening and stretchability-are controlled by a convolution of chemical composition, strand conformation and network topology. Yet, since the discovery of rubber vulcanization by Charles Goodyear in 1839, the internal organization of networks has remained a sealed 'black box'. While many studies show how network properties respond to topology variation, no method currently exists that would allow the decoding of the network structure from its properties. We address this problem by analysing networks' nonlinear responses to deformation to quantify their crosslink density, strand flexibility and fraction of stress-supporting strands. The decoded structural information enables the quality control of network synthesis, comparison of targeted to actual architecture and network classification according to the effectiveness of stress distribution. The developed forensic approach is a vital step in future implementation of artificial intelligence principles for soft matter design.

13.
Nat Immunol ; 13(2): 162-9, 2012 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-22231517

RESUMO

Memory T cells exert antigen-independent effector functions, but how these responses are regulated is unclear. We discovered an in vivo link between flagellin-induced NLRC4 inflammasome activation in splenic dendritic cells (DCs) and host protective interferon-γ (IFN-γ) secretion by noncognate memory CD8(+) T cells, which could be activated by Salmonella enterica serovar Typhimurium, Yersinia pseudotuberculosis and Pseudomonas aeruginosa. We show that CD8α(+) DCs were particularly efficient at sensing bacterial flagellin through NLRC4 inflammasomes. Although this activation released interleukin 18 (IL-18) and IL-1ß, only IL-18 was required for IFN-γ production by memory CD8(+) T cells. Conversely, only the release of IL-1ß, but not IL-18, depended on priming signals mediated by Toll-like receptors. These findings provide a comprehensive mechanistic framework for the regulation of noncognate memory T cell responses during bacterial immunity.


Assuntos
Proteínas Reguladoras de Apoptose/imunologia , Linfócitos T CD8-Positivos/imunologia , Proteínas de Ligação ao Cálcio/imunologia , Células Dendríticas/imunologia , Memória Imunológica , Inflamassomos/imunologia , Interferon gama/imunologia , Animais , Flagelina/imunologia , Interleucina-18/imunologia , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Camundongos , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , Salmonelose Animal/imunologia , Salmonella typhimurium/imunologia , Transdução de Sinais/imunologia , Baço/imunologia , Receptores Toll-Like/imunologia , Infecções por Yersinia pseudotuberculosis/imunologia
14.
Blood ; 139(15): 2347-2354, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35108372

RESUMO

Substantial heterogeneity within mutant TP53 acute myeloid leukemia (AML) and myelodysplastic syndrome with excess of blast (MDS-EB) precludes the exact assessment of prognostic impact for individual patients. We performed in-depth clinical and molecular analysis of mutant TP53 AML and MDS-EB to dissect the molecular characteristics in detail and determine its impact on survival. We performed next-generation sequencing on 2200 AML/MDS-EB specimens and assessed the TP53 mutant allelic status (mono- or bi-allelic), the number of TP53 mutations, mutant TP53 clone size, concurrent mutations, cytogenetics, and mutant TP53 molecular minimal residual disease and studied the associations of these characteristics with overall survival. TP53 mutations were detected in 230 (10.5%) patients with AML/MDS-EB with a median variant allele frequency of 47%. Bi-allelic mutant TP53 status was observed in 174 (76%) patients. Multiple TP53 mutations were found in 49 (21%) patients. Concurrent mutations were detected in 113 (49%) patients. No significant difference in any of the aforementioned molecular characteristics of mutant TP53 was detected between AML and MDS-EB. Patients with mutant TP53 have a poor outcome (2-year overall survival, 12.8%); however, no survival difference between AML and MDS-EB was observed. Importantly, none of the molecular characteristics were significantly associated with survival in mutant TP53 AML/MDS-EB. In most patients, TP53 mutations remained detectable in complete remission by deep sequencing (73%). Detection of residual mutant TP53 was not associated with survival. Mutant TP53 AML and MDS-EB do not differ with respect to molecular characteristics and survival. Therefore, mutant TP53 AML/MDS-EB should be considered a distinct molecular disease entity.


Assuntos
Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Citogenética , Humanos , Leucemia Mieloide Aguda/diagnóstico , Mutação , Síndromes Mielodisplásicas/diagnóstico , Proteína Supressora de Tumor p53/genética
15.
Arch Biochem Biophys ; 752: 109843, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38072298

RESUMO

Self-assembling nanoparticles (saNP) and nanofibers were found in the recombinant coronavirus SARS-CoV-2 S1, S2, RBD and N proteins purified by affinity chromatography using Ni Sepharose. Scanning electron (SEM), atomic force (AFM) microscopy on mica or graphite surface and in liquid as well as dynamic light scattering (DLS) revealed nanostructures of various sizes. AFM in liquid cell without drying on the surface showed mean height of S1 saNP 80.03 nm, polydispersity index (PDI) 0.006; for S2 saNP mean height 93.32 nm, PDI = 0.008; for N saNP mean height 16.71 nm, PDI = 0.99; for RBD saNP mean height 16.25 nm, PDI = 0.55. Ratios between the height and radius of each saNP in the range 0.1-0.5 suggested solid protein NP but not vesicles with internal empty spaces. The solid but not empty structures of the protein saNP were also confirmed by STEM after treatment of saNP with the standard contrasting agent uranyl acetate. The saNP remained stable after multiple freeze-thaw cycles in water and hyperosmotic solutions for 2 years at -20 °C. Receptor-mediated penetration of the SARS-CoV-2 S1 and RBD saNP in the African green mokey kidney Vero cells with the specific receptors for ß-coronavirus reproduction was more efficient compared to unspecific endocytosis into MDCK cells without the specific receptors. Amyloid-like structures were revealed in the SARS-CoV-2 S1, S2, RBD and N saNP by means of their interaction with Thioflavin T and Congo Red dyes. Taken together, spontaneous formation of the amyloid-like self-assembling nanostructures due to the internal affinity of the SARS-CoV-2 virion proteins might induce proteinopathy in patients, including conformational neurodegenerative diseases, change stability of vaccines and diagnostic systems.


Assuntos
COVID-19 , Nanoestruturas , Animais , Humanos , Chlorocebus aethiops , SARS-CoV-2 , Células Vero , Proteínas Recombinantes , Amiloide , Proteínas Amiloidogênicas
16.
PLoS Biol ; 19(10): e3001420, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34634044

RESUMO

Animals modulate sensory processing in concert with motor actions. Parallel copies of motor signals, called corollary discharge (CD), prepare the nervous system to process the mixture of externally and self-generated (reafferent) feedback that arises during locomotion. Commonly, CD in the peripheral nervous system cancels reafference to protect sensors and the central nervous system from being fatigued and overwhelmed by self-generated feedback. However, cancellation also limits the feedback that contributes to an animal's awareness of its body position and motion within the environment, the sense of proprioception. We propose that, rather than cancellation, CD to the fish lateral line organ restructures reafference to maximize proprioceptive information content. Fishes' undulatory body motions induce reafferent feedback that can encode the body's instantaneous configuration with respect to fluid flows. We combined experimental and computational analyses of swimming biomechanics and hair cell physiology to develop a neuromechanical model of how fish can track peak body curvature, a key signature of axial undulatory locomotion. Without CD, this computation would be challenged by sensory adaptation, typified by decaying sensitivity and phase distortions with respect to an input stimulus. We find that CD interacts synergistically with sensor polarization to sharpen sensitivity along sensors' preferred axes. The sharpening of sensitivity regulates spiking to a narrow interval coinciding with peak reafferent stimulation, which prevents adaptation and homogenizes the otherwise variable sensor output. Our integrative model reveals a vital role of CD for ensuring precise proprioceptive feedback during undulatory locomotion, which we term external proprioception.


Assuntos
Retroalimentação Sensorial/fisiologia , Sistema da Linha Lateral/fisiologia , Propriocepção/fisiologia , Potenciais de Ação/fisiologia , Adaptação Fisiológica , Animais , Fenômenos Biomecânicos , Modelos Biológicos , Natação/fisiologia , Fatores de Tempo , Peixe-Zebra/fisiologia
17.
J Exp Biol ; 227(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38680114

RESUMO

Animals exhibit an abundant diversity of forms, and this diversity is even more evident when considering animals that can change shape on demand. The evolution of flexibility contributes to aspects of performance from propulsive efficiency to environmental navigation. It is, however, challenging to quantify and compare body parts that, by their nature, dynamically vary in shape over many time scales. Commonly, body configurations are tracked by labelled markers and quantified parametrically through conventional measures of size and shape (descriptor approach) or non-parametrically through data-driven analyses that broadly capture spatiotemporal deformation patterns (shape variable approach). We developed a weightless marker tracking technique and combined these analytic approaches to study wing morphological flexibility in hoverfeeding Anna's hummingbirds (Calypte anna). Four shape variables explained >95% of typical stroke cycle wing shape variation and were broadly correlated with specific conventional descriptors such as wing twist and area. Moreover, shape variables decomposed wing deformations into pairs of in-plane and out-of-plane components at integer multiples of the stroke frequency. This property allowed us to identify spatiotemporal deformation profiles characteristic of hoverfeeding with experimentally imposed kinematic constraints, including through shape variables explaining <10% of typical shape variation. Hoverfeeding in front of a visual barrier restricted stroke amplitude and elicited increased stroke frequencies together with in-plane and out-of-plane deformations throughout the stroke cycle. Lifting submaximal loads increased stroke amplitudes at similar stroke frequencies together with prominent in-plane deformations during the upstroke and pronation. Our study highlights how spatially and temporally distinct changes in wing shape can contribute to agile fluidic locomotion.


Assuntos
Aves , Voo Animal , Asas de Animais , Animais , Asas de Animais/anatomia & histologia , Asas de Animais/fisiologia , Aves/fisiologia , Aves/anatomia & histologia , Fenômenos Biomecânicos , Voo Animal/fisiologia
18.
Dig Dis ; 42(1): 70-77, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37956655

RESUMO

INTRODUCTION: Chronic pancreatitis (CP) is a relevant chronic medical problem whereby delayed presentation and poor patient understanding can cause adverse effects. Quality of patient information available on the internet about CP is not known. METHODS: A systematic review of the information about CP available online using the search term "chronic pancreatitis" in using the search engine Google has been conducted. The quality of the top 100 websites returned from this search term was analysed using the validated Ensuring Quality Information for Patients (EQIP) tool (maximum score 36). Additional items were included in the website analysis specific to CP. RESULTS: In total, 45 websites were eligible for analysis. The median EQIP score of the websites was 16 (interquartile range 12-19.5). The majority of websites originated from the USA and the United Kingdom with 31 and 11 websites, respectively. Provision of additional information was inconsistent, with most websites covering information regarding aetiology and advocating alcohol and tobacco cessation, but only few reporting on more complex issues. CONCLUSION: Internet available information about CP is of limited quality. There is an immediate need for high quality, patient targeted, and informative literature accessible on the internet about this topic.

19.
Pediatr Transplant ; 28(2): e14725, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38436099

RESUMO

BACKGROUND: Biliary complications are common in pediatric liver transplant. Strictures resistant to interventional radiology procedures can be extremely challenging to manage and may result in the need of surgery or retransplantation. METHODS: This case report illustrates the use of biodegradable stents post left lateral segment live donor liver transplant in a pediatric patient with a recalcitrant chronic stricture of the biliary-enteric anastomosis. The patient developed a high stricture requiring multiple interventions and eventual access of both the segment II and segment III ducts of the graft. RESULTS: To ensure adequate biliary drainage, two biodegradable stents were deployed using a "kissing-stent" technique. The stents were successfully deployed and allowed the patient to remain free from an internal-external biliary drain for 11 months, with eventual redeployment of an additional biodegradable stent. CONCLUSION: In patients with recalcitrant stenosis of the biliary anastomosis, biodegradable stents may provide durable drainage, optimizing graft function and delaying retransplantation in addition to keeping patients without external devices, thus improving quality of life.


Assuntos
Transplante de Fígado , Humanos , Criança , Constrição Patológica/cirurgia , Doadores Vivos , Qualidade de Vida , Stents
20.
Phys Chem Chem Phys ; 26(17): 13412-13419, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647047

RESUMO

Anodic aluminum oxide (AAO) membranes were used as templates to control orientation of an ion-channel forming columnar mesophase obtained by self assembly of a wedge-shaped sulfonate molecule. Inside the AAO structure, the director vector of the mesophase is oriented parallel to the pore axis due to the confinement effect. The molecular arrangement induced by the spatial confinement within the pores is extended over several microns into the remnant film on the AAO surface. The homeotropic alignment of the channels promotes unidimensional ion conduction through the film plane, which is manifested by a considerable increase in conductivity relative to isotropic samples.

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