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Although viral hepatocellular carcinoma (HCC) is declining, nonviral HCC, which often is the end stage of nonalcoholic or alcoholic steatohepatitis (NASH, ASH), is on an upward trajectory. Immune checkpoint inhibitors (ICIs) that block the T cell inhibitory receptor PD-1 were approved for treatment of all HCC types. However, only a minority of HCC patients show a robust and sustained response to PD-1 blockade, calling for improved understanding of factors that negatively impact response rate and duration and the discovery of new adjuvant treatments that enhance ICI responsiveness. Using a mouse model of NASH-driven HCC, we identified peritumoral fibrosis as a potential obstacle to T cell-mediated tumor regression and postulated that antifibrotic medications may increase ICI responsiveness. We now show that the angiotensin II receptor inhibitor losartan, a commonly prescribed and safe antihypertensive drug, reduced liver and peritumoral fibrosis and substantially enhanced anti-PD-1-induced tumor regression. Although losartan did not potentiate T cell reinvigoration, it substantially enhanced HCC infiltration by effector CD8+ T cells compared to PD-1 blockade alone. The beneficial effects of losartan correlated with blunted TGF-ß receptor signaling, reduced collagen deposition, and depletion of immunosuppressive fibroblasts.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Linfócitos T CD8-Positivos , Losartan , Cirrose Hepática/patologiaRESUMO
Recent HIV-1 vaccine development has centered on "near native" soluble envelope glycoprotein (Env) trimers that are artificially stabilized laterally (between protomers) and apically (between gp120 and gp41). These mutations have been leveraged for use in membrane-expressed Env mRNA vaccines, although their effects in this context are unclear. To address this question, we used virus-like particle (VLP) produced in 293T cells. Uncleaved (UNC) trimers were laterally unstable upon gentle lysis from membranes. However, gp120/gp41 processing improved lateral stability. Due to inefficient gp120/gp41 processing, UNC is incorporated into VLPs. A linker between gp120 and gp41 neither improved trimer stability nor its antigenic profile. An artificially introduced enterokinase cleavage site allowed post-expression gp120/gp41 processing, concomitantly increasing trimer stability. Gp41 N-helix mutations I559P and NT1-5 imparted lateral trimer stability, but also reduced gp120/gp41 processing and/or impacted V2 apex and interface NAb binding. I559P consistently reduced recognition by HIV+ human plasmas, further supporting antigenic differences. Mutations in the gp120 bridging sheet failed to stabilize membrane trimers in a pre-fusion conformation, and also reduced gp120/gp41 processing and exposed non-neutralizing epitopes. Reduced glycan maturation and increased sequon skipping were common side effects of these mutations. In some cases, this may be due to increased rigidity which limits access to glycan processing enzymes. In contrast, viral gp120 did not show glycan skipping. A second, minor species of high mannose gp160 was unaffected by any mutations and instead bypasses normal folding and glycan maturation. Including the full gp41 cytoplasmic tail led to markedly reduced gp120/gp41 processing and greatly increased the proportion of high mannose gp160. Remarkably, monoclonal antibodies were unable to bind to this high mannose gp160 in native protein gels. Overall, our findings suggest caution in leveraging stabilizing mutations in nucleic acid-based immunogens to ensure they impart valuable membrane trimer phenotypes for vaccine use.
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Proteína gp41 do Envelope de HIV , HIV-1 , Humanos , Proteína gp41 do Envelope de HIV/genética , Proteína gp41 do Envelope de HIV/metabolismo , Glicosilação , Manose/metabolismo , Mutação , Glicoproteínas/metabolismo , Proteína gp120 do Envelope de HIV/genética , Proteína gp120 do Envelope de HIV/metabolismo , Anticorpos Anti-HIVRESUMO
Point mutations in leucine-rich repeat kinase 2 (LRRK2) cause Parkinson's disease and augment LRRK2's kinase activity. However, cellular pathways that endogenously enhance LRRK2 kinase function have not been identified. While overexpressed Rab29 draws LRRK2 to Golgi membranes to increase LRRK2 kinase activity, there is little evidence that endogenous Rab29 performs this function under physiological conditions. Here, we identify Rab38 as a novel physiologic regulator of LRRK2 in melanocytes. In mouse melanocytes, which express high levels of Rab38, Rab32, and Rab29, knockdown (or CRISPR knockout) of Rab38, but not Rab32 or Rab29, decreases phosphorylation of multiple LRRK2 substrates, including Rab10 and Rab12, by both endogenous LRRK2 and exogenous Parkinson's disease-mutant LRRK2. In B16-F10 mouse melanoma cells, Rab38 drives LRRK2 membrane association and overexpressed kinase-active LRRK2 shows striking pericentriolar recruitment, which is dependent on the presence of endogenous Rab38 but not Rab32 or Rab29. Consistently, knockdown or mutation of BLOC-3, the guanine nucleotide exchange factor for Rab38 and Rab32, inhibits Rab38's regulation of LRRK2. Deletion or mutation of LRRK2's Rab38-binding site in the N-terminal armadillo domain decreases LRRK2 membrane association, pericentriolar recruitment, and ability to phosphorylate Rab10. In sum, our data identify Rab38 as a physiologic regulator of LRRK2 function and lend support to a model in which LRRK2 plays a central role in Rab GTPase coordination of vesicular trafficking.
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Membranas Intracelulares , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Melanócitos , Proteínas rab de Ligação ao GTP , Animais , Camundongos , Complexo de Golgi/enzimologia , Complexo de Golgi/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Melanócitos/metabolismo , Mutação , Doença de Parkinson/metabolismo , Fosforilação , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , Células HEK293 , Humanos , Expressão Gênica , Domínios Proteicos , Ligação Proteica , Membranas Intracelulares/metabolismoRESUMO
High levels of sour rot on propiconazole-treated lemon fruit that were stored for extended times in some California packinghouses in 2020 and 2021 initiated surveys on fungicide sensitivity of the causal pathogen. In isolations from diseased fruit in 2020 to 2023, 157 isolates of Geotrichum spp. were obtained. Using species-specific primers, 143 were determined to be G. citri-aurantii and 15 were G. candidum. Isolates of G. citri-aurantii were either sensitive (EC50 0.06 to 0.34 µg/ml), moderately resistant (EC50 1.20 to 2.34 µg/ml), or highly resistant (EC50 >17.68 µg/ml) to propiconazole. There was incomplete cross resistance to cyproconazole, another demethylation inhibitor fungicide pending postharvest registration on citrus in the United States: isolates sensitive to propiconazole were sensitive, isolates moderately resistant to propiconazole were sensitive, and isolates highly resistant were moderately resistant to cyproconazole (EC50 0.11 to 0.63 µg/ml, 0.19 to 0.73 µg/ml, and 2.66 to 6.79 µg/ml, respectively). All except one isolate of G. candidum were highly resistant to both fungicides (EC50 >9.55). Isolates of both species were all considered sensitive to natamycin (EC50 1.18 to 5.01 µg/ml). In lemon fruit inoculations with G. candidum, the incidence of typical sour rot increased from 4.7% to 68.2% when inoculum was amended 2 µg/ml or 100 µg/ml cycloheximide, respectively, a compound known to suppress host defenses. In co-inoculations with 1:1 mixtures of the two Geotrichum spp., G. candidum was only recovered from the centers of decay lesions, whereas G. citri-aurantii was also obtained from the advancing margins. We conclude that G. candidum is a secondary pathogen of lemons, and its presence was favored by extended late-season storage of senescent fruit with reduced defense mechanisms.
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BACKGROUND & AIMS: Early detection of pancreatic cancer (PaC) can drastically improve survival rates. Approximately 25% of subjects with PaC have type 2 diabetes diagnosed within 3 years prior to the PaC diagnosis, suggesting that subjects with type 2 diabetes are at high risk of occult PaC. We have developed an early-detection PaC test, based on changes in 5-hydroxymethylcytosine (5hmC) signals in cell-free DNA from plasma. METHODS: Blood was collected from 132 subjects with PaC and 528 noncancer subjects to generate epigenomic and genomic feature sets yielding a predictive PaC signal algorithm. The algorithm was validated in a blinded cohort composed of 102 subjects with PaC, 2048 noncancer subjects, and 1524 subjects with non-PaCs. RESULTS: 5hmC differential profiling and additional genomic features enabled the development of a machine learning algorithm capable of distinguishing subjects with PaC from noncancer subjects with high specificity and sensitivity. The algorithm was validated with a sensitivity for early-stage (stage I/II) PaC of 68.3% (95% confidence interval [CI], 51.9%-81.9%) and an overall specificity of 96.9% (95% CI, 96.1%-97.7%). CONCLUSIONS: The PaC detection test showed robust early-stage detection of PaC signal in the studied cohorts with varying type 2 diabetes status. This assay merits further clinical validation for the early detection of PaC in high-risk individuals.
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Ácidos Nucleicos Livres , Diabetes Mellitus Tipo 2 , Neoplasias Pancreáticas , Humanos , Diabetes Mellitus Tipo 2/diagnóstico , Epigenômica , Detecção Precoce de Câncer , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genéticaRESUMO
The mammalian intestine is a complex environment that is constantly exposed to Ags derived from food, microbiota, and metabolites. Intestinal dendritic cells (DC) have the responsibility of establishing oral tolerance against these Ags while initiating immune responses against mucosal pathogens. We now know that DC are a heterogeneous population of innate immune cells composed of classical and monocyte-derived DC, Langerhans cells, and plasmacytoid DC. In the intestine, DC are found in organized lymphoid tissues, such as the mesenteric lymph nodes and Peyer's patches, as well as in the lamina propria. In this Brief Review, we review recent work that describes a division of labor between and collaboration among gut DC subsets in the context of intestinal homeostasis and inflammation. Understanding relationships between DC subtypes and their biological functions will rationalize oral vaccine design and will provide insights into treatments that quiet pathological intestinal inflammation.
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Imunidade nas Mucosas , Mucosa Intestinal/imunologia , Células de Langerhans/imunologia , Nódulos Linfáticos Agregados/imunologia , Animais , Humanos , Inflamação/imunologia , Inflamação/patologia , Mucosa Intestinal/patologia , Células de Langerhans/patologia , Linfonodos/imunologia , Linfonodos/patologia , Mesentério/imunologia , Mesentério/patologia , Nódulos Linfáticos Agregados/patologiaRESUMO
Human mesenchymal stem cells (hMSCs) are under intense study for applications of cell and gene therapeutics because of their unique immunomodulatory and regenerative properties. Safe and efficient genetic modification of hMSCs could increase their clinical potential by allowing functional expression of therapeutic transgenes or control over behavior and differentiation. Viral gene delivery is efficient, but suffers from safety issues, while nonviral methods are safe, but highly inefficient, especially in hMSCs. Our lab previously demonstrated that priming cells before delivery of DNA complexes with dexamethasone (DEX), an anti-inflammatory glucocorticoid drug, significantly increases hMSC transfection success. This work systematically investigates the mechanisms of hMSC transfection and DEX-mediated enhancement of transfection. Our results show that hMSC transfection and its enhancement by DEX are decreased by inhibiting classical intracellular transport and nuclear import pathways, but DEX transfection priming does not increase cellular or nuclear internalization of plasmid DNA (pDNA). We also show that hMSC transgene expression is largely affected by pDNA promoter and enhancer sequence changes, but DEX-mediated enhancement of transfection is unaffected by any pDNA sequence changes. Furthermore, DEX-mediated transfection enhancement is not the result of increased transgene messenger RNA transcription or stability. However, DEX-priming increases total protein synthesis by preventing hMSC apoptosis induced by transfection, resulting in increased translation of transgenic protein. DEX may also promote further enhancement of transgenic reporter enzyme activity by other downstream mechanisms. Mechanistic studies of nonviral gene delivery will inform future rationally designed technologies for safe and efficient genetic modification of clinically relevant cell types.
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Dexametasona/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Transfecção/métodos , Transformação Genética , Células Cultivadas , Expressão Gênica , HumanosRESUMO
Peripartum cardiomyopathy is a rare form of acute heart failure but the major cause of all deaths in pregnant patients with heart failure. Improved survival rates in recent years, however, emphasize the importance of early recognition and initiation of heart failure treatment. This article, therefore, attempts to raise awareness among cardiac and obstetric anesthesiologists as well as intensivists of this often fatal diagnosis. This review summarizes theories of the pathophysiology and outcome of peripartum cardiomyopathy. Based on the most recent literature, it further outlines diagnostic criteria and treatment options including medical management, mechanical circulatory support devices, and heart transplantation. Earlier recognition of this rare condition and a new generation of mechanical circulatory devices has contributed to the improved outcome. More frequently, patients in cardiogenic shock who fail medical management are successfully bridged to recovery on extracorporeal circulatory devices or survive with a long-lasting implantable ventricular assist device. The outcome of transplanted patients with peripartum cardiomyopathy, however, is worse compared to other recipients of heart transplants and warrants further investigation in the future.
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Cardiomiopatias/terapia , Oxigenação por Membrana Extracorpórea/métodos , Insuficiência Cardíaca/terapia , Período Periparto , Complicações Cardiovasculares na Gravidez/terapia , Doença Aguda , Cardiomiopatias/diagnóstico , Cardiomiopatias/fisiopatologia , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Período Periparto/fisiologia , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico , Complicações Cardiovasculares na Gravidez/fisiopatologia , Resultado do TratamentoRESUMO
BACKGROUND: Patients with anemia frequently undergo surgery, as it is unclear at what threshold clinicians should consider delaying surgery for preoperative anemia optimization. The primary objective of this study was to determine whether there is an association of varying degrees of anemia and transfusion with 30-day mortality. METHODS: This is a retrospective cohort study using the American College of Surgeons National Surgical Quality Improvement Program database from 2011 to 2013. Cohorts were analyzed based on preoperative hematocrit range-patients with: (1) no anemia, (2) hematocrit ≥33% and <36% in females or <39% in males, (3) hematocrit ≥30% and <33%, (4) hematocrit ≥27% and <30%, (5) hematocrit ≥24% and <27%, and (6) hematocrit ≥21% and less than 24%. Multivariable logistic regression was used to analyze the association of anemia and transfusion with 30-day in-hospital mortality. RESULTS: The odds for 30-day mortality increased incrementally as the hematocrit ranges decreased, in which preoperative hematocrit between 21 and 24% had the highest odds for this outcome (odds ratio [OR] 6.50, p < 0.0001) compared to the reference group (no anemia). The use of transfusion increased the odds of mortality even further (OR 5.57, p < 0.0001). Among patients that received an intra-/postoperative transfusion, preoperative anemia was not predictive of mortality. CONCLUSIONS: Healthcare providers making preoperative clinical decisions for patients undergoing elective surgery should consider the degree of preoperative anemia and likelihood of perioperative transfusion.
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Transfusão de Sangue , Procedimentos Cirúrgicos Eletivos/mortalidade , Hematócrito , Idoso , Anemia/mortalidade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Cuidados Pré-Operatórios , Estudos Retrospectivos , Fatores de RiscoRESUMO
Intra-hospital transport (IHT) of intensive care unit (ICU) patients is associated with a 30% to 60% incidence of adverse events (AEs). This prospective observational study collected data from 200 patient transports from a 24-bed cardiovascular intensive care unit (ICU) between July 2017 and December 2017. Phase 1 of the study focused on identifying and correcting deficiencies in nurses' knowledge regarding IHT. Phase 2 observed the occurrence and type of AEs during the IHT of ICU patients with and without physician accompaniment. The preeducation mean nursing knowledge score was 30.8 ± 10.2 (scale 0-100), and postcurriculum test mean score was 80 ± 20.2 (p < .001). In a series of 200 ICU transports, the incidence of AEs was 21.5% (n = 43). In patients who were unstable prior to transport, there was no difference in complications with or without a physician present (p = 0.40, χ = 0.696, odds ratio = 0.643, 95% confidence interval: 0.245-1.96). Patient needs during transport were met with preexisting orders or treatment orders received telephonically. Nurses' knowledge of transport standards improved significantly with education. Physician presence did not affect outcomes. The interventions needed to respond to complications did not require physician presence. In this cohort, there was no statistically significant benefit from physician attendance in transport.
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Doenças Cardiovasculares/terapia , Cuidados Críticos/normas , Estado Terminal/terapia , Transporte de Pacientes , Enfermagem de Cuidados Críticos , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: Perioperative risk factors and the clinical impact of acute kidney injury (AKI) and failure after lung transplantation are not well described. The incidences of AKI and acute renal failure (ARF), potential perioperative contributors to their development, and postdischarge healthcare needs were evaluated. DESIGN: Retrospective. SETTING: University hospital. PARTICIPANTS: Patients undergoing lung transplantation between January 1, 2011 and December 31, 2015. MEASURED DATA: The incidences of AKI and ARF, as defined using the Risk, Injury, Failure, Loss, End-Stage Renal Disease criteria, were measured. Perioperative events were analyzed to identify risk factors for renal compromise. A comparison of ventilator days, intensive care unit (ICU) and hospital lengths of stay (LOS), 1-year readmissions, and emergency department visits was performed among AKI, ARF, and uninjured patients. MEASUREMENTS AND MAIN RESULTS: Ninety-seven patients underwent lung transplantation; 22 patients developed AKI and 35 patients developed ARF. Patients with ARF had significantly longer ICU LOS (12 days v 4 days, p < 0.001); ventilator days (4.5 days v 1 day, p < 0.001); and hospital LOS (22.5 days v 14 days, p < 0.001) compared with uninjured patients. Patients with AKI also had significantly longer ICU and hospital LOS. Patients with ARF had significantly more emergency department visits and hospital readmissions (2 v 1 readmissions, p = 0.002) compared with uninjured patients. A univariable analysis suggested that prolonged surgical time, intraoperative vasopressor use, and cardiopulmonary bypass use were associated with the highest increased risk for AKI. Intraoperative vasopressor use and cardiopulmonary bypass mean arterial pressure <60 mmHg were identified as independent risk factors by multivariable analysis for AKI. CONCLUSION: The severity of AKI was associated with an increase in the use of healthcare resources after surgery and discharge. Certain risk factors appeared modifiable and may reduce the incidence of AKI and ARF.
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Injúria Renal Aguda/economia , Custos de Cuidados de Saúde , Recursos em Saúde/economia , Recursos em Saúde/estatística & dados numéricos , Transplante de Pulmão/economia , Complicações Pós-Operatórias/economia , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Adulto , Feminino , Custos de Cuidados de Saúde/tendências , Humanos , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/tendências , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
OBJECTIVES: The hemodynamic consequences of ventilation of intubated patients during transport either by hand or using a transport ventilator have not been reported in patients after cardiac surgery. The authors hypothesized that bag-mask ventilation would alter end-tidal CO2 during transport and hemodynamic parameters in patients post-cardiac surgery. DESIGN: A prospective, randomized trial. SETTING: A university-affiliated tertiary care hospital. PARTICIPANTS: Cardiac surgery patients. INTERVENTIONS: Thirty-six patients were randomized to hand ventilation or machine ventilation. Hemodynamic variables including blood pressure, heart rate, peripheral saturation of oxygen, and end-tidal carbon dioxide (ETCO2) were measured in these patients prior to transport, every 2 minutes during transport and upon arrival in the intensive care unit (ICU). Pulmonary artery pressure (PA) pressures were measured at origin and at destination. MEASUREMENTS AND MAIN RESULTS: Outcomes were changes from baseline in end-tidal CO2, hemodynamic changes from baseline and pulmonary artery pressure changes from origin to destination. The average transport time between the 2 groups was not different: 5 minutes for patients ventilated by hand and 5.47 minutes for patients ventilated with a transport ventilator (p = 0.369 by 2-sided t-test). The difference in all measured changes in ETCO2 between hand-ventilated and machine-ventilated patients during transport was 2.74 mmHg (p = 0.013). The difference between operating room and ICU ETCO2 from each cohort was 1.31 mmHg (p = 0.067). The difference in PAmean measured at origin and destination was 0.783 mmHg (p = 0.622). All other hemodynamic variables were not different during transport. CONCLUSIONS: Hand ventilation during transport was associated with greater change from baseline of ETCO2 compared to machine ventilation during transport after cardiac surgery, but this did not translate into any difference in hemodynamic changes upon arrival in ICU. A hemodynamic benefit of machine transport ventilation to cardiac patients was not demonstrated.
Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Hemodinâmica/fisiologia , Respiração Artificial/métodos , Transporte de Pacientes/métodos , Idoso , Procedimentos Cirúrgicos Cardíacos/normas , Estudos de Coortes , Feminino , Mãos , Humanos , Intubação Intratraqueal/métodos , Intubação Intratraqueal/normas , Masculino , Pessoa de Meia-Idade , Ventilação não Invasiva/métodos , Ventilação não Invasiva/normas , Estudos Prospectivos , Respiração Artificial/normas , Transporte de Pacientes/normas , Ventiladores Mecânicos/normasRESUMO
OBJECTIVES: Chronic endobronchial infections with Pseudomonas aeruginosa contribute to bronchiectasis and progressive loss of lung function in patients with cystic fibrosis. This study aimed to evaluate the therapeutic potential of a novel macrocyclic peptide, rhesus θ-defensin-1 (RTD-1), by characterizing its in vitro antipseudomonal activity and in vivo efficacy in a murine model of chronic Pseudomonas lung infection. METHODS: Antibacterial testing of RTD-1 was performed on 41 clinical isolates of P. aeruginosa obtained from cystic fibrosis patients. MIC, MBC, time-kill and post-antibiotic effects were evaluated following CLSI-recommended methodology, but using anion-depleted Mueller-Hinton broth. RTD-1 was nebulized daily for 7 days to cystic fibrosis transmembrane conductance regulator (CFTR) F508del-homozygous mice infected using the agar bead model of chronic P. aeruginosa lung infection. In vivo activity was evaluated by change in lung bacterial burden, airway leucocytes and body weight. RESULTS: RTD-1 exhibited potent in vitro bactericidal activity against mucoid and non-mucoid strains of P. aeruginosa (MIC90â=â8 mg/L). Cross-resistance was not observed when tested against MDR and colistin-resistant isolates. Time-kill studies indicated very rapid, concentration-dependent bactericidal activity of RTD-1 with ≥3 log10 cfu/mL reductions at concentrations ≥4× MIC. No post-antibiotic effect was observed. In vivo, nebulized treatment with RTD-1 significantly decreased lung P. aeruginosa burden (mean difference of -1.30 log10 cfu; Pâ=â0.0061), airway leucocytes (mean difference of -0.37 log10; Pâ=â0.0012) and weight loss (mean difference of -12.62% at day 7; Pâ<â0.05) when compared with controls. CONCLUSIONS: This study suggests that RTD-1 is a promising potential therapeutic agent for cystic fibrosis airway disease.
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Antibacterianos/administração & dosagem , Defensinas/administração & dosagem , Macaca mulatta , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Carga Bacteriana , Peso Corporal , Fibrose Cística/complicações , Defensinas/farmacologia , Modelos Animais de Doenças , Humanos , Contagem de Leucócitos , Pulmão/microbiologia , Pulmão/patologia , Masculino , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Resultado do TratamentoRESUMO
Fetal alcohol exposure (FAE) can lead to a variety of behavioral and physiological disturbances later in life. Understanding how alcohol (ethanol, EtOH) affects fetal brain development is essential to guide the development of better therapeutics for FAE. One of EtOH's many pharmacological targets is the γ-aminobutyric acid type A receptor (GABAAR), which plays a prominent role in early brain development. Acute EtOH potentiates inhibitory currents carried by certain GABAAR subtypes, whereas chronic EtOH leads to persistent alterations in GABAAR subunit composition, localization and function. We recently introduced a flavonoid compound, dihydromyricetin (DHM), which selectively antagonizes EtOH's intoxicating effects in vivo and in vitro at enhancing GABAAR function as a candidate for alcohol abuse pharmacotherapy. Here, we studied the effect of FAE on physiology, behavior and GABAAR function of early adolescent rats and tested the utility of DHM as a preventative treatment for FAE-induced disturbances. Gavage administration of EtOH (1.5, 2.5, or 5.0 g/kg) to rat dams on day 5, 8, 10, 12, and 15 of pregnancy dose-dependently reduced female/male offspring ratios (largely through decreased numbers of female offspring) and offspring body weights. FAE (2.5 g/kg) rats tested on postnatal days (P) 25-32 also exhibited increased anxiety and reduced pentylenetetrazol (PTZ)-induced seizure threshold. Patch-clamp recordings from dentate gyrus granule cells (DGCs) in hippocampal slices from FAE (2.5 g/kg) rats at P25-35 revealed reduced sensitivity of GABAergic miniature inhibitory postsynaptic currents (mIPSCs) and tonic current (Itonic) to potentiation by zolpidem (0.3 µM). Interestingly, potentiation of mIPSCs by gaboxadol increased, while potentiation of Itonic decreased in DGCs from FAE rats. Co-administration of EtOH (1.5 or 2.5 g/kg) with DHM (1.0 mg/kg) in pregnant dams prevented all of the behavioral, physiological, and pharmacological alterations observed in FAE offspring. DHM administration alone in pregnant rats had no adverse effect on litter size, progeny weight, anxiety level, PTZ seizure threshold, or DGC GABAAR function. Our results indicate that FAE induces long-lasting alterations in physiology, behavior, and hippocampal GABAAR function and that these deficits are prevented by DHM co-treatment of EtOH-exposed dams. The absence of adverse side effects and the ability of DHM to prevent FAE consequences suggest that DHM is an attractive candidate for development as a treatment for prevention of fetal alcohol spectrum disorders.
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Ansiedade/prevenção & controle , Etanol/administração & dosagem , Transtornos do Espectro Alcoólico Fetal/prevenção & controle , Flavonóis/uso terapêutico , Receptores de GABA-A/fisiologia , Potenciais Sinápticos/fisiologia , Fatores Etários , Animais , Animais Recém-Nascidos , Ansiedade/induzido quimicamente , Ansiedade/fisiopatologia , Relação Dose-Resposta a Droga , Etanol/toxicidade , Feminino , Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Flavonóis/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Masculino , Técnicas de Cultura de Órgãos , Gravidez , Ratos , Ratos Sprague-Dawley , Potenciais Sinápticos/efeitos dos fármacosRESUMO
Maggots in a wound ("myiasis") cannot be considered maggot therapy (therapeutic myiasis) unless, at a minimum, the species is known to be safe and effective, and the maggots have been properly disinfected. Documenting treatment details is critical and allows us to determine the cause of problems, if they arise.
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We aimed to evaluate the lasting functional imprinting of exercise (EX) and catechin (CAT) on the vascular function of middle-age mice switched to a proatherogenic environment. C57BL/6J mice (n = 10-15 in each group) fed a regular diet (RD) were exposed from the age of 1 to 9 months either to EX (voluntary running; 2.7 ± 0.2 km/day), to the polyphenol CAT (30 mg/kg/day in drinking water), or to physical inactivity (PI). At 9 months of age, EX and CAT were stopped and mice either remained on the RD or were fed a Western diet (WD) for an additional 3 months. At 12 months of age, mice from all groups fed a WD had similar body mass, systolic blood pressure, and plasma total cholesterol, glucose, insulin, and isoprostane. Compared to the RD, the WD induced an indomethacin-sensitive aortic endothelium-dependent and independent dysfunction in PI mice (p < 0.05) that was prevented by both EX and CAT; this benefit was associated with a higher (p < 0.05) non-nitric oxide/non-prostacyclin endothelium-dependent relaxation. While EX, but not PI or CAT, prevented vascular dysfunction induced by the WD in cerebral arteries, it had no effect in femoral arteries. The profiles of activity of antioxidant enzymes and of proinflammatory gene expression in the aorta suggest a better adaptation of EX > CAT > PI mice to stress. In conclusion, our data suggest that a postnatal exposure to EX, but not to CAT, imprints an adaptive defense capacity in the vasculature against a deleterious change in lifestyle.
Assuntos
Antioxidantes/farmacologia , Artérias/fisiologia , Catequina/farmacologia , Endotélio Vascular/fisiologia , Esforço Físico , Fatores Etários , Animais , Artérias/metabolismo , Aterosclerose/prevenção & controle , Glicemia , Pressão Sanguínea , Peso Corporal , Colesterol/sangue , Dieta Aterogênica , Endotélio Vascular/metabolismo , Meio Ambiente , Insulina/sangue , Isoprostanos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Despite numerous studies and recommendations, the acceptance of treatments involving medicinal maggots in many clinics has been slow. Several factors may account for this, including the gender of nurses administering the treatment, their level of work experience, and their perceived level of personal stress. The aim of the study was to assess the impact of selected variables (gender, work experience, stress level) on the readiness of nurses to administer maggot debridement therapy (MDT), which is a form of biodebridement. The study population was a cohort of 290 wound care nurses providing specialist care for patients with chronic wounds. It was assumed that the identified variables may determine the implementation of larval therapy in everyday professional practice. A subsample of 35 men and 35 women was further analyzed to determine if gender, work experience, and/or personal stress levels were correlated with attitudes towards the utilization of maggots in biodebridement. Assessment tools included the Perceived Stress Scale (PSS-10) and the MDT 10 Perception Assessment Questionnaire, a protocol by which the subject ranked six wound photographs in order of repulsiveness and responded to questions regarding demographic variables, which include education and work experience. The visual perception of pictures of a wound with larvae is indirectly an indicator of the attitude towards larval therapy. Selection of the photograph with maggots on the wound as the most repulsive image was associated with a personal appraisal of not being ready to implement maggot therapy (chi-square = 8.430, p = 0.015). Low work experience (chi-square = 14.039, df = 4, p = 0.007), and low readiness for MDT (chi-square = 8.430, df = 2, p = 0.015) were also associated with unpreparedness to administer maggot therapy. Neither gender nor perceived stress level were exclusively associated with disgust for maggots or lack of readiness to implement MDT. Low professional experience and a deficit of knowledge in maggot therapy may negatively affect the readiness of nurses to administer biodebridement. Gender and personal stress levels do not affect nurses' readiness to utilize larval therapy.
RESUMO
Although viral hepatocellular carcinoma (HCC) is declining, non-viral HCC, which often is the end-stage of non-alcoholic or alcoholic steatohepatitis (NASH, ASH), is on an upward trajectory. Immune checkpoint inhibitors (ICI) that block the T cell inhibitory receptor PD-1 were approved for treatment of all HCC types. However, only a small portion of HCC patients show a robust and sustained response to PD-1 blockade, calling for improved understanding of factors that negatively impact response rate and duration and the discovery of new adjuvant treatments that enhance ICI responsiveness. Using a mouse model of NASH-driven HCC, we identified peritumoral fibrosis as a potential obstacle to T cell mediated tumor regression and postulated that anti-fibrotic medications may increase ICI responsiveness. We now show that the angiotensin II receptor inhibitor losartan, a commonly prescribed and safe antihypertensive drug, reduced liver and peritumoral fibrosis and substantially enhanced anti-PD-1 induced tumor regression. Although losartan did not potentiate T cell reinvigoration, it substantially enhanced HCC infiltration by effector CD8 + T cells compared to PD-1 blockade alone. The beneficial effects of losartan correlated with inhibition of TGF-ß receptor signaling, collagen deposition and depletion of immunosuppressive fibroblasts. Significance: Immune checkpoint inhibitors are used in HCC treatment but overall response rates for single agent PD-1/PD-L1 blockers have remained stubbornly low. Using a mouse model of NASH-driven HCC, we show that co-treatment with the safe and inexpensive angiotensin II receptor inhibitor losartan substantially enhanced anti-PD-1 triggered HCC regression. Although losartan did not influence the reinvigoration of exhausted CD8 + T cells it considerably enhanced their intratumoral invasion, which we postulated to be compromised by peritumoral fibrosis. Indeed, the beneficial effect of losartan correlated with inhibition of TGF-ß signaling and collagen deposition, and depletion of immunosuppressive fibroblasts. Losartan should be evaluated for its adjuvant activity in HCC patients undergoing PD-1/PD-L1 blocking therapy.
RESUMO
Cystic fibrosis (CF) is characterized by a chronic neutrophilic inflammatory response resulting in airway remodeling and progressive loss of lung function. Doxycycline is a tetracycline antibiotic that inhibits matrix metalloproteinase 9, a protease known to be associated with the severity of lung disease in CF. The pharmacokinetics of doxycycline was investigated during the course of a clinical trial to evaluate the short-term efficacy and safety in adults with CF. Plasma samples were obtained from 14 patients following a single intravenous dose and after 2 and 4 weeks of oral administration of doses ranging from 40 to 200 mg daily. The data were analyzed using noncompartmental and compartmental pharmacokinetics. The maximum concentration of drug in serum (C(max)) and area under the concentration-time curve from 0 h to infinity (AUC(0-∞)) values ranged from 1.0 to 3.16 mg/liter and 15.2 to 47.8 mg/liter × h, respectively, following single intravenous doses of 40 to 200 mg. C(max) and time to maximum concentration of drug in serum (T(max)) values following multiple-dose oral administration ranged from 1.15 to 3.04 mg/liter and 1.50 to 2.33 h, respectively, on day 14 and 1.48 to 3.57 mg/liter and 1.00 to 2.17 on day 28. Predose sputum/plasma concentration ratios on days 14 and 28 ranged from 0.33 to 1.1 (mean, 0.71 ± 0.33), indicating moderate pulmonary penetration. A 2-compartment model best described the combined intravenous and oral data. Absorption was slow and delayed (absorption rate constant [K(a)], 0.414 h(-1); lag time, 0.484 h) but complete (bioavailability [F], 1.16). The distribution and elimination half-lives were 0.557 and 18.1 h, respectively. Based on these data, the plasma concentrations at the highest dose, 200 mg/day, are in the range reported to produce anti-inflammatory effects in vivo and should be evaluated in clinical trials.
Assuntos
Fibrose Cística/tratamento farmacológico , Doxiciclina/farmacocinética , Glândulas Exócrinas/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz , Administração Oral , Adolescente , Adulto , Área Sob a Curva , Disponibilidade Biológica , Cromatografia de Fase Reversa , Fibrose Cística/enzimologia , Fibrose Cística/patologia , Relação Dose-Resposta a Droga , Doxiciclina/administração & dosagem , Glândulas Exócrinas/enzimologia , Glândulas Exócrinas/patologia , Feminino , Meia-Vida , Humanos , Injeções Intravenosas , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Escarro/química , Estados UnidosRESUMO
A hallmark of cystic fibrosis is the massive recruitment of neutrophils into the lung compartment in response to chronic Pseudomonas aeruginosa infection. The overexuberant neutrophilic response results in release of proteases (e.g. neutrophil elastase and matrix metalloproteinase-9) leading to matrix breakdown, airway remodeling, and progressive loss of lung function. Doxycycline is used clinically for the management of periodontitis due to its potent direct inhibition of matrix metalloproteinases; however, little is known regarding its potential anti-inflammatory properties and clinical utility in the context of cystic fibrosis airway disease. CF (IB3-1) and corrected (S9) bronchial epithelial cell lines were used to determine the cytotoxicity and anti-inflammatory effects of doxycycline in-vitro. Exposure to doxycycline, at low concentrations, resulted in minimal cell death and dose dependent reductions in release of CXCL-8 and MMP-9 protein. To confirm these findings, mechanistic analysis revealed ERK 1/2, p38, and JNK, but not NF-κB p65 dependent cell signaling inhibition with doxycycline treatment. These findings indicate that doxycycline exhibits anti-inflammatory activity in CF lung epithelial cells at concentrations below the cytotoxic potential. These data are encouraging and indicate in-vivo studies are warranted.