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1.
N Engl J Med ; 385(21): 1961-1973, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34788507

RESUMO

BACKGROUND: The goal of gene therapy for patients with hemophilia A is to safely impart long-term stable factor VIII expression that predictably ameliorates bleeding with the use of the lowest possible vector dose. METHODS: In this phase 1-2 trial, we infused an investigational adeno-associated viral (AAV) vector (SPK-8011) for hepatocyte expression of factor VIII in 18 men with hemophilia A. Four dose cohorts were enrolled; the lowest-dose cohort received a dose of 5 × 1011 vector genomes (vg) per kilogram of body weight, and the highest-dose cohort received 2 × 1012 vg per kilogram. Some participants received glucocorticoids within 52 weeks after vector administration either to prevent or to treat a presumed AAV capsid immune response. Trial objectives included evaluation of the safety and preliminary efficacy of SPK-8011 and of the expression and durability of factor VIII. RESULTS: The median safety observation period was 36.6 months (range, 5.5 to 50.3). A total of 33 treatment-related adverse events occurred in 8 participants; 17 events were vector-related, including 1 serious adverse event, and 16 were glucocorticoid-related. Two participants lost all factor VIII expression because of an anti-AAV capsid cellular immune response that was not sensitive to immune suppression. In the remaining 16 participants, factor VIII expression was maintained; 12 of these participants were followed for more than 2 years, and a one-stage factor VIII assay showed no apparent decrease in factor VIII activity over time (mean [±SD] factor VIII activity, 12.9±6.9% of the normal value at 26 to 52 weeks when the participants were not receiving glucocorticoids vs. 12.0±7.1% of the normal value at >52 weeks after vector administration; 95% confidence interval [CI], -2.4 to 0.6 for the difference between matched pairs). The participants had a 91.5% reduction (95% CI, 88.8 to 94.1) in the annualized bleeding rate (median rate, 8.5 events per year [range, 0 to 43.0] before vector administration vs. 0.3 events per year [range, 0 to 6.5] after vector administration). CONCLUSIONS: Sustained factor VIII expression in 16 of 18 participants who received SPK-8011 permitted discontinuation of prophylaxis and a reduction in bleeding episodes. No major safety concerns were reported. (Funded by Spark Therapeutics and the National Heart, Lung, and Blood Institute; ClinicalTrials.gov numbers, NCT03003533 and NCT03432520.).


Assuntos
Dependovirus , Fator VIII/genética , Fator VIII/metabolismo , Terapia Genética , Vetores Genéticos , Hemofilia A/sangue , Adolescente , Adulto , Seguimentos , Genótipo , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Hemofilia A/genética , Hemofilia A/prevenção & controle , Hepatócitos/metabolismo , Humanos , Terapia de Imunossupressão , Masculino , Pessoa de Meia-Idade , Adulto Jovem
2.
Am J Physiol Heart Circ Physiol ; 326(1): H190-H202, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37921665

RESUMO

Myoendothelial feedback (MEF), the endothelium-dependent vasodilation following sympathetic vasoconstriction (mediated by smooth muscle to endothelium gap junction communication), has been well studied in resistance arteries of males, but not females. We hypothesized that MEF responses would be similar between the sexes, but different in the relative contribution of the underlying nitric oxide and hyperpolarization mechanisms, given that these mechanisms differ between the sexes in agonist-induced endothelium-dependent dilation. We measured MEF responses (diameter changes) of male and female first- to second-order mouse mesenteric arteries to phenylephrine (10 µM) over 30 min using isolated pressure myography ± blinded inhibition of nitric oxide synthase (NOS) using Nω-nitro-l-arginine methyl ester (l-NAME; 0.1-1.0 mM), hyperpolarization using 35 mM KCl, or transient receptor potential vanilloid 4 (TRPV4) channels using GSK219 (0.1-1.0 µM) or RN-1734 (30 µM). MEF was similar [%dilation (means ± SE): males = 26.7 ± 2.0 and females = 26.1 ± 1.9 at 15 min] and significantly inhibited by l-NAME (1.0 mM) at 15 min [%dilation (means ± SE): males = 8.2 ± 3.3, P < 0.01; females = 6.8 ± 1.9, P < 0.001] and over time (P < 0.01) in both sexes. l-NAME (0.1 mM) + 35 mM KCl nearly eliminated MEF in both sexes (P < 0.001-0.0001). Activation of TRPV4 with GSK101 (0.1-10 µM) induced similar dilation between the sexes. Inhibition of TRPV4, which is reportedly involved in the hyperpolarization mechanism, did not inhibit MEF in either sex. Similar expression of eNOS was found between the sexes with Western blot. Thus, MEF is prominent and similar in murine first- and second-order mesenteric resistance arteries of both sexes, and reliant primarily on NOS and secondarily on hyperpolarization, but not TRPV4.NEW & NOTEWORTHY We found that female mesenteric resistance arteries have similar postconstriction dilatory responses (i.e., myoendothelial feedback) to a sympathetic neurotransmitter analog as male arteries. Both sexes use nitric oxide synthase (NOS) and hyperpolarization, but not TRPV4, in this response. Moreover, the key protein involved in this pathway (eNOS) is similarly expressed in these arteries between the sexes. These similarities are surprising given that agonist-induced endothelium-dependent dilatory mechanisms differ in these arteries between the sexes.


Assuntos
Óxido Nítrico Sintase , Canais de Cátion TRPV , Camundongos , Masculino , Feminino , Animais , NG-Nitroarginina Metil Éster/farmacologia , Retroalimentação , Canais de Cátion TRPV/metabolismo , Artérias Mesentéricas/metabolismo , Vasodilatação , Óxido Nítrico/metabolismo , Endotélio Vascular/metabolismo
3.
Support Care Cancer ; 32(5): 276, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38589646

RESUMO

PURPOSE: To study the effects of delaying pegfilgrastim administration following high-dose cytarabine (HiDAC) consolidation in AML patients on time to neutrophil count recovery, infectious complications, and survival. METHODS: Single-center retrospective chart review of 55 patients receiving pegfilgrastim as early administration (within 72 h) or delayed administration (after 72 h) of HiDAC. RESULTS: The difference in neutrophil recovery time was similar between the early and delayed groups (18 days versus 19 days, p < 0.28). Infections were seen in four patients in the early administration group following chemotherapy compared to none in the delayed group (p = 0.04). Febrile neutropenia rates were also decreased in the delayed administration group (23.1% versus 10.3%, p = 0.28) as well as a trend towards longer median survival (16 months versus 19 months, p = 0.69) and overall survival (21 months versus 31 months, p = 0.47). CONCLUSION: A difference in time to neutrophil recovery was not observed between the early and delayed administration groups yet decreased infectious complications may support the delayed administration of pegfilgrastim in these patients.


Assuntos
Citarabina , Filgrastim , Leucemia Mieloide Aguda , Polietilenoglicóis , Humanos , Citarabina/efeitos adversos , Quimioterapia de Consolidação , Estudos Retrospectivos , Leucemia Mieloide Aguda/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
4.
Cytometry A ; 103(11): 839-850, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37768325

RESUMO

High-dimensional immunoprofiling is essential for studying host response to immunotherapy, infection, and disease in murine model systems. However, the difficulty of multiparameter panel design combined with a lack of existing murine tools has prevented the comprehensive study of all major leukocyte phenotypes in a single assay. Herein, we present a 40-color flow cytometry panel for deep immunophenotyping of murine lymphoid tissues, including the spleen, blood, Peyer's patches, inguinal lymph nodes, bone marrow, and thymus. This panel uses a robust set of surface markers capable of differentiating leukocyte subsets without the use of intracellular staining, thus allowing for the use of cells in downstream functional experiments or multiomic analyses. Our panel classifies T cells, B cells, natural killer cells, innate lymphoid cells, monocytes, macrophages, dendritic cells, basophils, neutrophils, eosinophils, progenitors, and their functional subsets by using a series of co-stimulatory, checkpoint, activation, migration, and maturation markers. This tool has a multitude of systems immunology applications ranging from serial monitoring of circulating blood signatures to complex endpoint analysis, especially in pre-clinical settings where treatments can modulate leukocyte abundance and/or function. Ultimately, this 40-color panel resolves a diverse array of immune cells on the axes of time, tissue, and treatment, filling the niche for a modern tool dedicated to murine immunophenotyping.


Assuntos
Imunidade Inata , Tecido Linfoide , Camundongos , Animais , Citometria de Fluxo/métodos , Linfócitos T , Células Matadoras Naturais , Imunofenotipagem
5.
Neurol Sci ; 44(12): 4473-4479, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37453951

RESUMO

INTRODUCTION: Small fiber neuropathy [SFN] is a common peripheral neurologic disorder with a vast array of implicated etiologies. It has previously been proposed that some forms of immune-mediated small fiber neuropathy are driven by vasculitis, though antinuclear cytoplasmic antibodies [ANCA] antibodies have not commonly been reported in association with SFN, thus far. We present this case series to discuss the observation of a possible novel association between ANCA and SFN. METHODS: This is a retrospective case series of 6 patients with SFN and ANCA positivity, with and without systemic manifestations. Patients included were diagnosed with SFN by skin biopsy or autonomic function testing and were seropositive for ANCA by ELISA. RESULTS: Six patients are outlined, including 4 females and 2 males. Antigen specific antibodies were MPO alone in 4 cases, PR3 alone in 1 case and both MPO and PR3 in 1 case. Systemic vasculitis was noted in 2 patients. Five patients received immunosuppression. Three patients experienced partial improvement, while symptoms stabilized in 3 patients. DISCUSSION: This is the first series of patients with suspected immune-mediated SFN and ANCA antibody positivity, raising the possibility of ANCA mediated isolated SFN. This is in contradistinction to the more typical ANCA-mediated peripheral neuropathy manifestations of mononeuropathy multiplex or axonal sensorimotor neuropathy. We cannot unequivocally prove ANCA-associated vasculitis [AAV] causality in these cases; however, the stabilization in SFN symptomatology and associated improvement in ANCA antibody titer, after AAV treatment, may be indicative of an association.


Assuntos
Neuropatia de Pequenas Fibras , Vasculite , Masculino , Feminino , Humanos , Anticorpos Anticitoplasma de Neutrófilos/análise , Neuropatia de Pequenas Fibras/complicações , Neuropatia de Pequenas Fibras/diagnóstico , Estudos Retrospectivos , Ensaio de Imunoadsorção Enzimática , Peroxidase
6.
Proc Natl Acad Sci U S A ; 117(23): 12674-12685, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32430322

RESUMO

Robust cytotoxic T cell infiltration has proven to be difficult to achieve in solid tumors. We set out to develop a flexible protocol to efficiently transfect tumor and stromal cells to produce immune-activating cytokines, and thus enhance T cell infiltration while debulking tumor mass. By combining ultrasound with tumor-targeted microbubbles, membrane pores are created and facilitate a controllable and local transfection. Here, we applied a substantially lower transmission frequency (250 kHz) than applied previously. The resulting microbubble oscillation was significantly enhanced, reaching an effective expansion ratio of 35 for a peak negative pressure of 500 kPa in vitro. Combining low-frequency ultrasound with tumor-targeted microbubbles and a DNA plasmid construct, 20% of tumor cells remained viable, and ∼20% of these remaining cells were transfected with a reporter gene both in vitro and in vivo. The majority of cells transfected in vivo were mucin 1+/CD45- tumor cells. Tumor and stromal cells were then transfected with plasmid DNA encoding IFN-ß, producing 150 pg/106 cells in vitro, a 150-fold increase compared to no-ultrasound or no-plasmid controls and a 50-fold increase compared to treatment with targeted microbubbles and ultrasound (without IFN-ß). This enhancement in secretion exceeds previously reported fourfold to fivefold increases with other in vitro treatments. Combined with intraperitoneal administration of checkpoint inhibition, a single application of IFN-ß plasmid transfection reduced tumor growth in vivo and recruited efficacious immune cells at both the local and distant tumor sites.


Assuntos
Imunoterapia/métodos , Interferon beta/genética , Neoplasias Experimentais/terapia , Linfócitos T/imunologia , Transfecção/métodos , Ondas Ultrassônicas , Animais , Linhagem Celular Tumoral , Membrana Celular/efeitos da radiação , Movimento Celular , Humanos , Interferon beta/metabolismo , Camundongos , Microbolhas/uso terapêutico , Linfócitos T/fisiologia
7.
J Sports Sci ; 41(16): 1573-1579, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38078436

RESUMO

Differences in workload exist between netball playing positions and competition levels, but no research has compared workloads experienced by the same elite players during national and international competitions. This study collected internal (heart rate) and external (PlayerLoad·min-1) workload data per match quarter from 44 players during a national competition and 12 players during an international competition. Nine players played in both competitions. Linear mixed models compared percentage of match quarter in each heart rate zone and PlayerLoad·min-1 between competitions for each playing position. Workloads against low- and high-ranked international opponents were also compared. Internal workloads were greater in national compared to international competition for GD and WD positions. PlayerLoad·min-1 was significantly higher by 8-13% in the national competition for positions WD and C, and by 5-8% in the international competition for GD and GA. Positional differences may indicate a role of the team's tactical style of play. Workloads were generally greater against higher- rather than lower-ranked international opponents. These results indicate that tactical factors in combination with playing position and opposition characteristics should be considered when preparing physically for matches.


Assuntos
Desempenho Atlético , Basquetebol , Humanos , Basquetebol/fisiologia , Carga de Trabalho , Desempenho Atlético/fisiologia , Frequência Cardíaca/fisiologia , Modelos Lineares
8.
Ann Vasc Surg ; 70: 370-377, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32603847

RESUMO

BACKGROUND: Arterial access and device delivery in endovascular aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR) have evolved from open femoral or iliac artery exposure to selective percutaneous arterial access. Although regional application of percutaneous access for these 2 procedures varies widely, the use of this technique continues to increase. Currently, differences in the use of percutaneous access between EVAR and TEVAR have not been well explored. The Gore Global Registry for Endovascular Aortic Treatment (GREAT) registry collected relevant data for evaluation of these issues and the comparative results between open and percutaneous approaches in regard to complication rates and length of stay (LOS). METHODS: This study was performed via a retrospective review of patients from the GREAT registry (Clinicaltrials.gov no. NCT01658787). The primary variable of this study was access site complications including postoperative hematoma, vessel dissection, and pseudoaneurysm. Patients were categorized by abdominal (EVAR) and thoracic (TEVAR) aortic procedures using percutaneous-only, cutdown-only, and combined vascular access techniques for a total of 6 groups. Standard statistical methodology was used to perform single-variable and multivariable analysis of a variety of covariates including LOS, geographical location of procedure, procedural success rate, and access sheath size. RESULTS: Of 4,781 patients from the GREAT registry, 3,837 (80.3%) underwent EVAR and 944 (19.7%) underwent TEVAR with percutaneous-only access techniques being used in 2,017 (42.2%) and cutdown-only in 2,446 (51.2%). There was variable application of percutaneous access by geographic region with Australia and New Zealand using this technique more frequently and Brazil using percutaneous access the least. No significant difference in the rate of access site complications was detected between the 6 groups of patients in the study; however, significantly lower rates of access site complications were associated with percutaneous-only compared with both cutdown-only and combined techniques (P = 0.03). In addition, associated with significantly higher rates of access site complications was longer LOS (P < 0.01). Average LOS was 5.2 days and was higher in the TEVAR group (10.1 days) than that in EVAR (4.0 days, P < 0.05). Increased sheath size does not appear to increase the risk of access site complication. CONCLUSIONS: There was no significant difference found in the complication rate between percutaneous and cutdown access techniques. This analysis demonstrates that percutaneous-only access is safe, has low complication rates, and has lower LOS compared with open access or combined access techniques.


Assuntos
Doenças da Aorta/cirurgia , Implante de Prótese Vascular , Cateterismo Periférico , Procedimentos Endovasculares , Artéria Femoral/cirurgia , Artéria Ilíaca/cirurgia , Idoso , Idoso de 80 Anos ou mais , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Cateterismo Periférico/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Punções , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Stents , Fatores de Tempo , Resultado do Tratamento
9.
Adv Neonatal Care ; 21(3): 189-197, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33009153

RESUMO

BACKGROUND: Diaper dermatitis (DD) causes discomfort and emotional distress and creates possible sources of infection among newborn intensive care unit infants. Diaper dermatitis remains prevalent despite studies documenting an understanding of prevention and treatment modalities. Standardizing perineal skin care guidelines could reduce DD. PURPOSE: Implement perineal skin care guidelines, while introducing novel diaper wipes, to decrease the incidence of DD by 20% within a 1-year period. METHODS: Our unit reviewed evidence-based literature to develop a standardized perineal care guideline for prevention and treatment, encompassing the use of novel, preservative-free diaper wipes with grapefruit seed extract. The outcome measures were the incidence and duration of DD. Process compliances were monitored. The balancing measure was the rate of fungal skin infection while using preservative-free wipes. FINDINGS: Between July 2017 and March 2019, 1070 infants were admitted for 1 or more days, with 11% of those being born at less than 30 weeks of gestational age. After guideline implementation in January 2018, the incidence of DD decreased by 16.7%. The incidence of severe cases dropped by 34.9%, with 3.5 days per 100 patient-days shortened duration. Process compliance was achieved. Neonates tolerated the novel wipes without increased fungal skin infection. IMPLICATIONS FOR PRACTICE: The Perineal Skin Care Guidelines could reduce the rate and duration of DD. Newborn intensive care unit infants tolerated the novel diaper wipes. IMPLICATIONS FOR RESEARCH: Additional research on wipes containing other types of extracts or ingredients.


Assuntos
Dermatite das Fraldas , Unidades de Terapia Intensiva Neonatal , Criança , Dermatite das Fraldas/prevenção & controle , Humanos , Lactente , Cuidado do Lactente , Recém-Nascido , Melhoria de Qualidade , Higiene da Pele
10.
N Engl J Med ; 377(23): 2215-2227, 2017 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-29211678

RESUMO

BACKGROUND: The prevention of bleeding with adequately sustained levels of clotting factor, after a single therapeutic intervention and without the need for further medical intervention, represents an important goal in the treatment of hemophilia. METHODS: We infused a single-stranded adeno-associated viral (AAV) vector consisting of a bioengineered capsid, liver-specific promoter and factor IX Padua (factor IX-R338L) transgene at a dose of 5×1011 vector genomes per kilogram of body weight in 10 men with hemophilia B who had factor IX coagulant activity of 2% or less of the normal value. Laboratory values, bleeding frequency, and consumption of factor IX concentrate were prospectively evaluated after vector infusion and were compared with baseline values. RESULTS: No serious adverse events occurred during or after vector infusion. Vector-derived factor IX coagulant activity was sustained in all the participants, with a mean (±SD) steady-state factor IX coagulant activity of 33.7±18.5% (range, 14 to 81). On cumulative follow-up of 492 weeks among all the participants (range of follow-up in individual participants, 28 to 78 weeks), the annualized bleeding rate was significantly reduced (mean rate, 11.1 events per year [range, 0 to 48] before vector administration vs. 0.4 events per year [range, 0 to 4] after administration; P=0.02), as was factor use (mean dose, 2908 IU per kilogram [range, 0 to 8090] before vector administration vs. 49.3 IU per kilogram [range, 0 to 376] after administration; P=0.004). A total of 8 of 10 participants did not use factor, and 9 of 10 did not have bleeds after vector administration. An asymptomatic increase in liver-enzyme levels developed in 2 participants and resolved with short-term prednisone treatment. One participant, who had substantial, advanced arthropathy at baseline, administered factor for bleeding but overall used 91% less factor than before vector infusion. CONCLUSIONS: We found sustained therapeutic expression of factor IX coagulant activity after gene transfer in 10 participants with hemophilia who received the same vector dose. Transgene-derived factor IX coagulant activity enabled the termination of baseline prophylaxis and the near elimination of bleeding and factor use. (Funded by Spark Therapeutics and Pfizer; ClinicalTrials.gov number, NCT02484092 .).


Assuntos
Fator IX/genética , Terapia Genética/métodos , Vetores Genéticos , Hemofilia B/terapia , Transgenes , Adolescente , Adulto , Dependovirus/imunologia , Fator IX/metabolismo , Fator IX/uso terapêutico , Vetores Genéticos/administração & dosagem , Hemofilia B/genética , Hemofilia B/metabolismo , Hemorragia/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Mol Phylogenet Evol ; 146: 106750, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32028034

RESUMO

Colletes Latreille (Hymenoptera: Colletidae) is a diverse genus with 518 valid species distributed in all biogeographic realms, except Australasia and Antarctica. Here we provide a comprehensive dated phylogeny for Colletes based on Bayesian and maximum likelihood-based analyses of DNA sequence data of six loci: 28S rDNA, cytochrome c oxidase subunit 1, elongation factor-1α copy F2, long-wavelength rhodopsin, RNA polymerase II and wingless. In total, our multilocus matrix consists of 4824 aligned base pairs for 143 species, including 112 Colletes species plus 31 outgroups (one stenotritid and a diverse array of colletids representing all subfamilies). Overall, analyses of each of the six single-locus datasets resulted in poorly resolved consensus trees with conflicting phylogenetic signal. However, our analyses of the multilocus matrix provided strong support for the monophyly of Colletes and show that it can be subdivided into five major clades. The implications of our phylogenetic results for future attempts at infrageneric classification for the Colletes of the world are discussed. We propose species groups for the Neotropical species of Colletes, the only major biogeographic realm for which no species groups have been proposed to date. Our dating analysis indicated that Colletes diverged from its sister taxon, Hemicotelles Toro and Cabezas, in the early Oligocene and that its extant lineages began diversifying only in the late Oligocene. According to our biogeographic reconstruction, Colletes originated in the Neotropics (most likely within South America) and then spread to the Nearctic very early in its evolutionary history. Geodispersal to the Old World occurred soon after colonization of the Northern Hemisphere. Lastly, the historical biogeography of Colletes is analyzed in light of available geological and palaeoenvironmental data.


Assuntos
Abelhas/classificação , Animais , Teorema de Bayes , Abelhas/genética , Funções Verossimilhança , Filogenia , Filogeografia , Análise de Sequência de DNA , América do Sul
12.
Glob Chang Biol ; 26(11): 6276-6295, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32914511

RESUMO

Climatic impacts are especially pronounced in the Arctic, which as a region is warming twice as fast as the rest of the globe. Here, we investigate how mean climatic conditions and rates of climatic change impact parasitoid insect communities in 16 localities across the Arctic. We focus on parasitoids in a widespread habitat, Dryas heathlands, and describe parasitoid community composition in terms of larval host use (i.e., parasitoid use of herbivorous Lepidoptera vs. pollinating Diptera) and functional groups differing in their closeness of host associations (koinobionts vs. idiobionts). Of the latter, we expect idiobionts-as being less fine-tuned to host development-to be generally less tolerant to cold temperatures, since they are confined to attacking hosts pupating and overwintering in relatively exposed locations. To further test our findings, we assess whether similar climatic variables are associated with host abundances in a 22 year time series from Northeast Greenland. We find sites which have experienced a temperature rise in summer while retaining cold winters to be dominated by parasitoids of Lepidoptera, with the reverse being true for the parasitoids of Diptera. The rate of summer temperature rise is further associated with higher levels of herbivory, suggesting higher availability of lepidopteran hosts and changes in ecosystem functioning. We also detect a matching signal over time, as higher summer temperatures, coupled with cold early winter soils, are related to high herbivory by lepidopteran larvae, and to declines in the abundance of dipteran pollinators. Collectively, our results suggest that in parts of the warming Arctic, Dryas is being simultaneously exposed to increased herbivory and reduced pollination. Our findings point to potential drastic and rapid consequences of climate change on multitrophic-level community structure and on ecosystem functioning and highlight the value of collaborative, systematic sampling effort.


Assuntos
Ecossistema , Herbivoria , Animais , Regiões Árticas , Groenlândia , Interações Hospedeiro-Parasita , Larva
13.
BJOG ; 127(4): 478-488, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31715077

RESUMO

OBJECTIVE: Women with pre-eclampsia have elevated circulating levels of soluble fms-like tyrosine kinase-1 (sFlt-1). Statins can reduce sFlt-1 from cultured cells and improve pregnancy outcome in animals with a pre-eclampsia-like syndrome. We investigated the effect of pravastatin on plasma sFlt-1 levels during pre-eclampsia. DESIGN: Blinded (clinician and participant), proof of principle, placebo-controlled trial. SETTING: Fifteen UK maternity units. POPULATION: We used a minimisation algorithm to assign 62 women with early-onset pre-eclampsia (24+0 -31+6  weeks of gestation) to receive pravastatin 40 mg daily (n = 30) or matched placebo (n = 32), from randomisation to childbirth. PRIMARY OUTCOME: Difference in mean plasma sFlt-1 levels over the first 3 days following randomisation. RESULTS: The difference in the mean maternal plasma sFlt-1 levels over the first 3 days after randomisation between the pravastatin (n = 27) and placebo (n = 29) groups was 292 pg/ml (95% CI -1175 to 592; P = 0.5), and over days 1-14 was 48 pg/ml (95% CI -1009 to 913; P = 0.9). Women who received pravastatin had a similar length of pregnancy following randomisation compared with those who received placebo (hazard ratio 0.84; 95% CI 0.50-1.40; P = 0.6). The median time from randomisation to childbirth was 9 days (interquartile range [IQR] 5-14 days) for the pravastatin group and 7 days (IQR 4-11 days) for the placebo group. There were three perinatal deaths in the placebo-treated group and no deaths or serious adverse events attributable to pravastatin. CONCLUSIONS: We found no evidence that pravastatin lowered maternal plasma sFlt-1 levels once early-onset pre-eclampsia had developed. Pravastatin appears to have no adverse perinatal effects. TWEETABLE ABSTRACT: Pravastatin does not improve maternal plasma sFlt-1 or placental growth factor levels following a diagnosis of early preterm pre-eclampsia #clinicaltrial finds.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Pravastatina/administração & dosagem , Pré-Eclâmpsia/tratamento farmacológico , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto , Método Duplo-Cego , Feminino , Idade Gestacional , Humanos , Pré-Eclâmpsia/sangue , Gravidez , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos
14.
Artigo em Inglês | MEDLINE | ID: mdl-37720693

RESUMO

Protective coatings based on an Al-Al2O3 metal matrix composite (MMC) were sprayed using dynamic metallization (DM), a low-pressure cold spray variant. A series of samples approximately 1 mm in thickness were sprayed using different spray process parameters (temperature, velocity) and different feedstock powder compositions (Al, Zn, Al2O3). This resulted in MMCs of different phase compositions and slightly different physical conditions of coating formation. The through-thickness residual stresses that accumulate in coatings during the spray process were studied using neutron diffraction in all phases comprising the MMCs. The overall residual stress in the coating (macrostress) was compressive, which is in good agreement with the data on residual stress observed in other cold spray coatings, accumulating as a result of the peening process. However, due to the slightly elevated spray temperature characteristic of DM in comparison with other cold spray variants, thermal stresses are also present and play an equally important role in the accumulation of residual stress in each phase. Because of the multi-phase composition and thermal mismatch between the metal and ceramic components of the MMC, inter-phase microstresses also accumulate. A micro-mechanical explanation of the observed tensile microstress in Al/Zn versus compressive stress in Al2O3 is proposed.

15.
J Neurochem ; 151(6): 764-776, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31539452

RESUMO

Fragile X syndrome (FXS) is caused by silencing of the FMR1 gene and consequent absence of its protein product, fragile X mental retardation protein (FMRP). FMRP is an RNA-binding protein that can suppress translation. The absence of FMRP leads to symptoms of FXS including intellectual disability and has been proposed to lead to abnormalities in synaptic plasticity. Synaptic plasticity, protein synthesis, and cellular growth pathways have been studied extensively in hippocampal slices from a mouse model of FXS (Fmr1 KO). Enhanced metabotropic glutamate receptor 5 (mGluR5)-dependent long-term depression (LTD), increased rates of protein synthesis, and effects on signaling molecules have been reported. These phenotypes were found under amino acid starvation, a condition that has widespread, powerful effects on activation and translation of proteins involved in regulating protein synthesis. We asked if this non-physiological condition could have effects on Fmr1 KO phenotypes reported in hippocampal slices. We performed hippocampal slice experiments in the presence and absence of amino acids. We measured rates of incorporation of a radiolabeled amino acid into protein to determine protein synthesis rates. By means of western blots, we assessed relative levels of total and phosphorylated forms of proteins involved in signaling pathways regulating translation. We measured evoked field potentials in area CA1 to assess the strength of the long-term depression response to mGluR activation. In the absence of amino acids, we replicate many of the reported findings in Fmr1 KO hippocampal slices, but in the more physiological condition of inclusion of amino acids in the medium, we did not find evidence of enhanced mGluR5-dependent LTD. Activation of mGluR5 increased protein synthesis in both wild type and Fmr1 KO. Moreover, mGluR5 activation increased eIF2α phosphorylation and decreased phosphorylation of p70S6k in slices from Fmr1 KO. We propose that the eIF2α response is a cellular attempt to compensate for the lack of regulation of translation by FMRP. Our findings call for a re-examination of the mGluR theory of FXS.


Assuntos
Aminoácidos/farmacologia , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Hipocampo/metabolismo , Depressão Sináptica de Longo Prazo/fisiologia , Biossíntese de Proteínas/fisiologia , Transdução de Sinais/fisiologia , Animais , Proteína do X Frágil da Deficiência Intelectual/genética , Hipocampo/efeitos dos fármacos , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Técnicas de Cultura de Órgãos , Biossíntese de Proteínas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
16.
Blood ; 129(26): 3486-3494, 2017 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-28432223

RESUMO

Friend leukemia virus integration 1 (FLI1), a critical transcription factor (TF) during megakaryocyte differentiation, is among genes hemizygously deleted in Jacobsen syndrome, resulting in a macrothrombocytopenia termed Paris-Trousseau syndrome (PTSx). Recently, heterozygote human FLI1 mutations have been ascribed to cause thrombocytopenia. We studied induced-pluripotent stem cell (iPSC)-derived megakaryocytes (iMegs) to better understand these clinical disorders, beginning with iPSCs generated from a patient with PTSx and iPSCs from a control line with a targeted heterozygous FLI1 knockout (FLI1+/-). PTSx and FLI1+/- iMegs replicate many of the described megakaryocyte/platelet features, including a decrease in iMeg yield and fewer platelets released per iMeg. Platelets released in vivo from infusion of these iMegs had poor half-lives and functionality. We noted that the closely linked E26 transformation-specific proto-oncogene 1 (ETS1) is overexpressed in these FLI1-deficient iMegs, suggesting FLI1 negatively regulates ETS1 in megakaryopoiesis. Finally, we examined whether FLI1 overexpression would affect megakaryopoiesis and thrombopoiesis. We found increased yield of noninjured, in vitro iMeg yield and increased in vivo yield, half-life, and functionality of released platelets. These studies confirm FLI1 heterozygosity results in pleiotropic defects similar to those noted with other critical megakaryocyte-specific TFs; however, unlike those TFs, FLI1 overexpression improved yield and functionality.


Assuntos
Síndrome da Deleção Distal 11q de Jacobsen/patologia , Megacariócitos/citologia , Proteína Proto-Oncogênica c-fli-1/sangue , Trombopoese , Animais , Plaquetas/metabolismo , Diferenciação Celular , Linhagem Celular , Humanos , Células-Tronco Pluripotentes Induzidas , Camundongos , Camundongos SCID , Proto-Oncogene Mas
17.
J Vasc Surg ; 70(1): 67-73, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30598353

RESUMO

OBJECTIVE: To date, no single scoring system for predicting 30-day mortality in patients with ruptured abdominal aortic aneurysms (rAAAs) has been endorsed by any vascular society or proven to definitively predict treatment futility. Three recently developed scoring systems for predicting 30-day mortality in patients with rAAA have been validated by their respective institutional data. The purpose of this study was to evaluate the accuracy of these rAAA mortality risk scores using an independent community hospital dataset. METHODS: Consecutive patients presenting with rAAA at Saint Joseph Hospital between January 1, 2009, and February 28, 2017, were used for validation. Logistic regression analysis was used to evaluate the association between risk score and odds of death. Confidence intervals were calculated using the Wilson method. Comparisons were made between models by calculating the area under the receiver operating characteristic (AUC) curves. RESULTS: Complete data from 38 patients was used for accuracy evaluation. The AUCs for the Dutch Aneurysm Score, Harborview Medical Center score, and Vascular Surgery Group of New England (VSGNE) score were 0.762, 0.792, and 0.860, respectively, for all patients. When evaluating 30-day mortality for patients undergoing ruptured endovascular aneurysm repair, the scores were 0.802, 0.893, and 0.927, respectively. The difference between scores did not reach statistical significance. All three indexes significantly associated with the mortality rate using logistic regression. CONCLUSIONS: Each risk score accurately predicted 30-day mortality using the independent dataset. The results suggest that the VSGNE score is the most accurate; however, differences in accuracy between each scoring system did not reach statistical significance. The Harborview Medical Center scoring system is based only on preoperative variables. Although the VSGNE score had the highest AUC in this analysis, it is dependent on intraoperative variables. The authors favor a single risk assessment tool, with consensus vascular societal approval, that incorporates preoperative variables and includes a tool for the prediction of treatment futility.


Assuntos
Aneurisma da Aorta Abdominal/mortalidade , Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/mortalidade , Ruptura Aórtica/cirurgia , Implante de Prótese Vascular/mortalidade , Técnicas de Apoio para a Decisão , Procedimentos Endovasculares/mortalidade , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Ruptura Aórtica/diagnóstico por imagem , Implante de Prótese Vascular/efeitos adversos , Bases de Dados Factuais , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
18.
J Fish Dis ; 42(7): 975-984, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31066066

RESUMO

A previous proteomic study examining the plasma acute-phase response of rainbow trout to sterile inflammation highlighted an unidentified 9.5-kDa spot using 2D-PAGE, which was dramatically increased. The 15 amino acid sequence obtained from this protein spot allowed rapid amplification of cDNA ends PCR to generate a 443-bp nucleotide sequence that was 98.6% similar to type-4 ice-structuring protein LS-12 from Atlantic salmon Salmo salar Linnaeus. Quantitative reverse translation PCR and an ELISA were used to measure gene expression and plasma concentrations of LS-12 following experimental intraperitoneal injection of rainbow trout with either 106 or 108 colony-forming units (CFU) of Flavobacterium psychrophilum. There was no significant change in the plasma concentration of LS-12 up to 15 days post-infection in any group. Hepatic LS-12 gene expression was significantly reduced at 3 and 6 days (p < 0.001) post-infection in fish injected with 108 CFU of F. psychrophilum relative to control fish, while branchial or head kidney expression was unchanged. Infected fish had significantly increased hepatic gene expression of serum amyloid A, confirming an acute-phase response. Under the conditions used, LS-12 is not a positive acute-phase protein in rainbow trout.


Assuntos
Reação de Fase Aguda/veterinária , Doenças dos Peixes/microbiologia , Proteínas de Peixes/genética , Infecções por Flavobacteriaceae/veterinária , Oncorhynchus mykiss/microbiologia , Reação de Fase Aguda/microbiologia , Animais , Proteínas de Peixes/sangue , Infecções por Flavobacteriaceae/microbiologia , Flavobacterium/patogenicidade , Reação em Cadeia da Polimerase , Proteômica
19.
J Mol Evol ; 86(8): 501-510, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30218341

RESUMO

Cycles of biologically relevant reactions are an alternative to an origin of life emerging from a steady state away from equilibrium. The cycles involve a rate at which polymers are synthesized and accumulate in microscopic compartments called protocells, and two rates in which monomers and polymers are chemically degraded by hydrolytic reactions. Recent experiments have demonstrated that polymers are synthesized from mononucleotides and accumulate during cycles of hydration and dehydration, which means that the rate of polymer synthesis during the dehydrated phase of the cycle is balanced (but not dominated) by the rate of polymer hydrolysis during the hydrated phase of the cycle. Furthermore, depurination must be balanced by the reverse process of repurination. Here we describe a computational model that was inspired by experimental results, can be generalized to accommodate other reaction parameters, and has qualitative predictive power.


Assuntos
Polímeros/química , Polímeros/síntese química , Desidratação , Hidratação , Hidrólise
20.
Nature ; 491(7425): 608-12, 2012 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-23135403

RESUMO

Defects in the availability of haem substrates or the catalytic activity of the terminal enzyme in haem biosynthesis, ferrochelatase (Fech), impair haem synthesis and thus cause human congenital anaemias. The interdependent functions of regulators of mitochondrial homeostasis and enzymes responsible for haem synthesis are largely unknown. To investigate this we used zebrafish genetic screens and cloned mitochondrial ATPase inhibitory factor 1 (atpif1) from a zebrafish mutant with profound anaemia, pinotage (pnt (tq209)). Here we describe a direct mechanism establishing that Atpif1 regulates the catalytic efficiency of vertebrate Fech to synthesize haem. The loss of Atpif1 impairs haemoglobin synthesis in zebrafish, mouse and human haematopoietic models as a consequence of diminished Fech activity and elevated mitochondrial pH. To understand the relationship between mitochondrial pH, redox potential, [2Fe-2S] clusters and Fech activity, we used genetic complementation studies of Fech constructs with or without [2Fe-2S] clusters in pnt, as well as pharmacological agents modulating mitochondrial pH and redox potential. The presence of [2Fe-2S] cluster renders vertebrate Fech vulnerable to perturbations in Atpif1-regulated mitochondrial pH and redox potential. Therefore, Atpif1 deficiency reduces the efficiency of vertebrate Fech to synthesize haem, resulting in anaemia. The identification of mitochondrial Atpif1 as a regulator of haem synthesis advances our understanding of the mechanisms regulating mitochondrial haem homeostasis and red blood cell development. An ATPIF1 deficiency may contribute to important human diseases, such as congenital sideroblastic anaemias and mitochondriopathies.


Assuntos
Eritroblastos/metabolismo , Eritropoese , Heme/biossíntese , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas/metabolismo , Anemia Sideroblástica/genética , Anemia Sideroblástica/metabolismo , Anemia Sideroblástica/patologia , Animais , Modelos Animais de Doenças , Eritroblastos/citologia , Ferroquelatase/metabolismo , Teste de Complementação Genética , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Mitocôndrias/patologia , Proteínas Mitocondriais/deficiência , Proteínas Mitocondriais/genética , Oxirredução , Proteínas/genética , Peixe-Zebra/metabolismo , Proteína Inibidora de ATPase
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