Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Dev Neurosci ; : 1-15, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38797164

RESUMO

INTRODUCTION: The complement response activates upon reperfusion in neonatal hypoxic-ischemic encephalopathy (HIE) and contributes to excessive neuroinflammation and worse outcomes. C5a is a powerful anaphylatoxin central to each of the complement pathways, and its engagement with C5aR1 is directly tied to brain injury and neuronal death. Reasoning C5aR1 antagonism can decrease excessive neuroinflammation and thereby improve neurological and functional outcomes, we tested this hypothesis in a rat model of HIE with PMX205, a small molecule that inhibits C5a-C5aR1 interaction. METHODS: Term-equivalent pups (P10-12) were subjected to mild-moderate HIE by Vannucci's method and treated with PMX205. We compared motor and cognitive outcomes with two behavioral tests each (food handling and accelerod; novel object recognition [NOR] and open field) to improve the accuracy of our conclusions. RESULTS: Improvements were observed in fine motor function, balance, and exploratory behaviors, but little to no improvement in recognition memory and gross motor function. Lesion area and histological assessments showed robust cortical neuroprotection from treatment but persistent injury to the CA1 region of the hippocampus. Better structural and functional outcomes were seen within 1 day of treatment, suggesting C5aR1 antagonism beyond the latent injury phase may impair recovery. In a dose-response experiment, cerebral area loss from injury was improved only in female rats, suggesting underlying sexual dimorphisms in the complement response. CONCLUSION: These results demonstrate proof-of-concept for targeting C5aR1 signaling in neonatal HIE with PMX205 and underscore the role of sex in hypoxic-ischemic injury.

2.
Am J Perinatol ; 40(13): 1446-1453, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-34674212

RESUMO

OBJECTIVE: The objective of this study was to determine the degree of progressive posthemorrhagic ventricular dilatation (PHVD) that is associated with a significant decrease in regional cerebral oxygen saturation (rScO2) in premature infants at risk for periventricular-intraventricular hemorrhage (PIVH). STUDY DESIGN: Cranial ultrasound (US) and near-infrared spectroscopy (NIRS) measurements of rScO2 were performed on inborn infants with birth weights less than 1,250 g on admission and at 1, 4, and 8 weeks of age. Infants with severe PIVH were studied weekly. A 1-hour average of rScO2 was compared with the frontal-occipital horn ratio (FOHR) measured the same day. Generalized linear models were used to analyze the relationship between FOHR and rScO2, by severity of PIVH, and adjusted for gestational age. Cut-off points of 0.55 for FOHR and 45% for rScO2 were used to calculate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: The study cohort included 63 infants with normal US, 15 with grade-1 or -2 PIVH (mild group), and 21 with grade-3 or -4 PIVH (severe group). Increases in FOHR in the severe group were associated with decreases in rScO2 at 1 week (p = 0.036), 4 weeks (p = 0.013), and 8 weeks of life (p = 0.001) compared with the normal and mild groups. Infants with FOHR greater than 0.55 were 92% more likely to have rScO2 less than 45% when compared with infants with FOHR less than 0.55 (OR = 0.08, 95% CI: [0.04, 0.13], p < 0.001). CONCLUSION: Progressive PHVD (FOHR > 0.55) is a strong predictor of compromised cerebral oxygenation. A combination of rScO2 and FOHR measurements may aid in identifying infants with PHVD that would benefit from early intervention. KEY POINTS: · Earlier intervention in PHVD may improve outcomes.. · PHVD is diagnosed with US measurements of ventricular size.. · FOHR > 0.55 is associated with decreased cerebral perfusion..


Assuntos
Hidrocefalia , Doenças do Prematuro , Recém-Nascido , Lactente , Humanos , Dilatação , Recém-Nascido Prematuro , Hidrocefalia/complicações , Idade Gestacional , Hemorragia Cerebral/diagnóstico por imagem
3.
Pediatr Res ; 89(1): 74-84, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32221474

RESUMO

The next phase of clinical trials in neonatal encephalopathy (NE) focuses on hypothermia adjuvant therapies targeting alternative recovery mechanisms during the process of hypoxic brain injury. Identifying infants eligible for neuroprotective therapies begins with the clinical detection of brain injury and classification of severity. Combining a variety of biomarkers (serum, clinical exam, EEG, movement patterns) with innovative clinical trial design and analyses will help target infants with the most appropriate and timely treatments. The timing of magnetic resonance imaging (MRI) and MR spectroscopy after NE both assists in identifying the acute perinatal nature of the injury (days 3-7) and evaluates the full extent and evolution of the injury (days 10-21). Early, intermediate outcome of neuroprotective interventions may be best defined by the 21-day neuroimaging, with recognition that the full neurodevelopmental trajectory is not yet defined. An initial evaluation of each new therapy at this time point may allow higher-throughput selection of promising therapies for more extensive investigation. Functional recovery can be assessed using a trajectory of neurodevelopmental evaluations targeted to a prespecified and mechanistically derived hypothesis of drug action. As precision medicine revolutionizes healthcare, it should also include the redesign of NE clinical trials to allow safe, efficient, and targeted therapeutics. IMPACT: As precision medicine revolutionizes healthcare, it should also include the redesign of NE clinical trials to allow faster development of safe, effective, and targeted therapeutics. This article provides a multidisciplinary perspective on the future of clinical trials in NE; novel trial design; study management and oversight; biostatistical methods; and a combination of serum, imaging, and neurodevelopmental biomarkers can advance the field and improve outcomes for infants affected by NE. Innovative clinical trial designs, new intermediate trial end points, and a trajectory of neurodevelopmental evaluations targeted to a prespecified and mechanistically derived hypothesis of drug action can help address common challenges in NE clinical trials and allow for faster selection and validation of promising therapies for more extensive investigation.


Assuntos
Pesquisa Biomédica/tendências , Encefalopatias/terapia , Ensaios Clínicos como Assunto , Doenças do Recém-Nascido/terapia , Neonatologia/tendências , Projetos de Pesquisa/tendências , Biomarcadores/sangue , Encefalopatias/diagnóstico por imagem , Encefalopatias/etiologia , Encefalopatias/fisiopatologia , Consenso , Técnica Delphi , Difusão de Inovações , Previsões , Humanos , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico por imagem , Doenças do Recém-Nascido/etiologia , Doenças do Recém-Nascido/fisiopatologia , Neuroimagem , Sociedades Médicas , Sociedades Científicas , Fatores de Tempo , Resultado do Tratamento
4.
Pediatr Res ; 81(4): 654-662, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28002390

RESUMO

BACKGROUND: Therapeutic hypothermia (HT) is the only intervention that improves outcomes in neonatal hypoxic-ischemic encephalopathy (HIE). However, the multifactorial mechanisms by which HT impacts HIE are incompletely understood. The complement system plays a major role in the pathogenesis of ischemia-reperfusion injuries such as HIE. We have previously demonstrated that HT modulates complement activity in vitro. METHODS: Term equivalent rat pups were subjected to unilateral carotid ligation followed by hypoxia (8% O2) for 45 min to simulate HIE. A subset of animals was subjected to HT (31-32°C for 6 h). Plasma and brain levels of C3a and C5a were measured. Receptors for C3a (C3aR) and C5a (C5aR) along with C1q, C3, and C9 were characterized in neurons, astrocytes, and microglia. RESULTS: We found that HT increased systemic expression of C3a and decreased expression of C5a after HIE. In the brain, C3aR and C5aR are predominantly expressed on microglia after HIE. HT increased local expression of C3aR and decreased expression on C5aR after HIE. Furthermore, HT decreased local expression of C1q, C3-products, and C9 in the brain. CONCLUSION: HT is associated with significant alteration of complement effectors and their cognate receptors. Complement modulation may improve outcomes in neonatal HIE.


Assuntos
Encefalopatias/sangue , Complemento C3a/análise , Complemento C5a/análise , Hipotermia Induzida , Hipóxia-Isquemia Encefálica/sangue , Animais , Animais Recém-Nascidos , Astrócitos/metabolismo , Encéfalo/patologia , Encefalopatias/terapia , Hipóxia , Hipóxia-Isquemia Encefálica/terapia , Microglia/metabolismo , Neurônios/metabolismo , Ratos , Ratos Wistar , Traumatismo por Reperfusão , Temperatura , Fatores de Tempo
5.
Transfusion ; 56(8): 2133-45, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27282513

RESUMO

BACKGROUND: Acute hemolytic transfusion reactions have a broad clinical presentation from mild and transitory signs and symptoms to shock, disseminated intravascular coagulation, renal failure, and death. We have recently developed a rat model of acute intravascular hemolysis showing that the classical complement pathway mediates antibody-dependent hemolysis. The objective of this study was to evaluate the role of the classical pathway inhibitor peptide inhibitor of complement C1 (PIC1) in this animal model. STUDY DESIGN AND METHODS: Male Wistar rats received a 15% transfusion of human red blood cells (RBCs) and blood was isolated from the animals up to 120 minutes. Animals received PIC1 either 2 minutes before or 0.5 minutes after transfusion. Sham-, vehicle-, and cobra venom factor (CVF)-treated animals were used as control groups with a subset of rats also receiving an equivalent dose of intravenous immunoglobulin (IVIG) before transfusion. Blood was analyzed for transfused RBC survival by flow cytometry and free hemoglobin (Hb) in isolated plasma by spectrophotometry. RESULTS: Vehicle-treated rats showed decreased human RBC survival and increased free Hb as expected. Rats receiving PIC1 before transfusion showed increased human RBC survival and decreased Hb similar to CVF-treated rats. Notably, rats receiving PIC1 after initiation of transfusion showed similar decreases in hemolysis as animals receiving PIC1 before transfusion. Compared to IVIG and saline controls, PIC1-treated animals demonstrated decreased hemolysis and protection from acute kidney injury. CONCLUSIONS: These results demonstrate that PIC1 has efficacy in an animal model of acute intravascular hemolysis in both prevention and rescue scenarios.


Assuntos
Complemento C1/antagonistas & inibidores , Hemólise/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Incompatibilidade de Grupos Sanguíneos/tratamento farmacológico , Contagem de Eritrócitos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Hemoglobinas/metabolismo , Humanos , Masculino , Peptídeos/uso terapêutico , Ratos , Ratos Wistar , Reação Transfusional/tratamento farmacológico
6.
Ann Allergy Asthma Immunol ; 116(5): 435-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27017558

RESUMO

BACKGROUND: Eosinophilic esophagitis (EoE) is a chronic disease that requires long-term medical management and monitoring. The eosinophil count determined during esophageal biopsy remains the gold standard for diagnosis and monitoring of EoE. Although markers of eosinophil degranulation correlate with symptoms, eosinophil counts do not correlate. Development of a noninvasive, cost-effective biomarker of eosinophil activation for the evaluation of EoE is an unmet medical need. OBJECTIVE: To conduct a proof-of-concept study to evaluate the potential for measuring urinary 3-bromotyrosine (3-BT) levels in creatinine normalized urine for quantifying eosinophil degranulation in EoE disease. METHODS: A mass spectrometry-based method of measuring normalized 3-BT levels, the Eosinophil Quantitated Urine Kinetic (EoQUIK), was developed, and proof-of-concept evaluation was performed for patients with EoE (n = 27), atopic controls (n = 24), and nonatopic controls (n = 24). RESULTS: EoQUIK revealed that median normalized 3-BT levels were increased 93-fold in patients with EoE compared with nonatopic controls (P = .01) and increased 13-fold in patients with EoE compared with atopic controls (P = .01). Cutoff thresholds were selected for EoQUIK that yielded a specificity of 100% and a negative predictive value of 100% for nonatopic controls and a specificity of 79% and a negative predictive value of 90% for atopic controls. In a logistic regression model, a urine 3-BT level greater than 20 pg per 400 mg of creatinine increased the odds of a patient having EoE by 4.8 (95% confidence interval, 1.14-20.5; P = .03) when compared with atopic controls after controlling for race and sex. CONCLUSION: These data provide proof of concept that EoQUIK can potentially be a useful noninvasive clinical tool in the evaluation of possible EoE.


Assuntos
Esofagite Eosinofílica/urina , Tirosina/análogos & derivados , Adolescente , Adulto , Bioensaio , Criança , Pré-Escolar , Esofagite Eosinofílica/diagnóstico , Esofagite Eosinofílica/imunologia , Eosinófilos/imunologia , Feminino , Humanos , Contagem de Leucócitos , Masculino , Tirosina/urina , Adulto Jovem
7.
BMC Pulm Med ; 16: 42, 2016 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-26987997

RESUMO

BACKGROUND: Budesonide and formoterol (BF) Spiromax® is a dry powder inhaler designed to deliver BF with maximum ease of use for patients with asthma or chronic obstructive pulmonary disease. METHODS: A phase 3b, 12-week, multicenter, double-blind, double-dummy, randomized, controlled trial in patients (≥12 years) with persistent asthma. PRIMARY OBJECTIVE: to demonstrate non-inferiority of twice-daily BF Spiromax 160/4.5 mcg to BF Turbuhaler® 200/6 mcg in change from baseline in weekly average of daily trough morning peak expiratory flow (PEF). Secondary endpoints included: Patient Satisfaction and Preference Questionnaire scores, change from baseline in evening PEF, trough forced expiratory volume in one second, percentage of symptom-free and rescue-free 24-hour periods, and safety. RESULTS: The analysis was based on the per-protocol population (BF Spiromax, n = 290; BF Turbuhaler, n = 284). The least squares mean change from baseline to week 12 in morning PEF was: BF Spiromax, 18.8 L/min and BF Turbuhaler, 21.8 L/min. Non-inferiority of BF Spiromax vs BF Turbuhaler was demonstrated (the lower limit of the 95% two-sided confidence interval was -9.02 L/min, which is greater than -15 L/min [the criteria specified for non-inferiority]). The mean difference in the total performance domains scores for BF Spiromax vs BF Turbuhaler were 0.248 at baseline and 0.353 at week 12 (both, p <0.001), indicating statistical superiority for BF Spiromax. No statistical or numerical differences were recorded in the total convenience domain score between the two devices. Scores for 'device preference' and 'willingness to continue' supported BF Spiromax at baseline and at week 12 (p = 0.0005 vs BF Turbuhaler). No significant between-group differences were observed in the other secondary efficacy endpoints. Both treatments were well tolerated, with no significant differences in adverse events or asthma exacerbations. CONCLUSIONS: This study demonstrates the non-inferiority of BF Spiromax vs BF Turbuhaler in patients (≥12 years) with asthma. More patients preferred the Spiromax device over Turbuhaler for its performance, and were willing to continue therapy with BF Spiromax beyond the 12-week study period. TRIAL REGISTRATION: NCT01803555; February 28, 2013.


Assuntos
Asma/tratamento farmacológico , Broncodilatadores/administração & dosagem , Budesonida/administração & dosagem , Inaladores de Pó Seco , Fumarato de Formoterol/administração & dosagem , Administração por Inalação , Adolescente , Adulto , Asma/fisiopatologia , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Preferência do Paciente , Satisfação do Paciente , Pico do Fluxo Expiratório , Resultado do Tratamento , Adulto Jovem
8.
Am J Respir Cell Mol Biol ; 52(5): 611-21, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25275225

RESUMO

Current treatments for inflammation associated with bronchopulmonary dysplasia (BPD) fail to show clinical efficacy. Foxm1, a transcription factor of the Forkhead box family, is a critical mediator of lung development and carcinogenesis, but its role in BPD-associated pulmonary inflammation is unknown. Immunohistochemistry and RNA analysis were used to assess Foxm1 in lung tissue from hyperoxia-treated mice and patients with BPD. LysM-Cre/Foxm1(-/-) mice, in which Foxm1 was deleted from myeloid-derived inflammatory cells, including macrophages, monocytes, and neutrophils, were exposed to neonatal hyperoxia, causing lung injury and remodeling. Measurements of lung function and flow cytometry were used to evaluate the effects of Foxm1 deletion on pulmonary inflammation and repair. Increased Foxm1 expression was observed in pulmonary macrophages of hyperoxia-exposed mice and in lung tissue from patients with BPD. After hyperoxia, deletion of Foxm1 from the myeloid cell lineage decreased numbers of interstitial macrophages (CD45(+)CD11b(+)Ly6C(-)Ly6G(-)F4/80(+)CD68(-)) and impaired alveologenesis and lung function. The exaggerated BPD-like phenotype observed in hyperoxia-exposed LysM-Cre/Foxm1(-/-) mice was associated with increased expression of neutrophil-derived myeloperoxidase, proteinase 3, and cathepsin g, all of which are critical for lung remodeling and inflammation. Our data demonstrate that Foxm1 influences pulmonary inflammatory responses to hyperoxia, inhibiting neutrophil-derived enzymes and enhancing monocytic responses that limit alveolar injury and remodeling in neonatal lungs.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Hiperóxia/complicações , Lesão Pulmonar/metabolismo , Pulmão/metabolismo , Pneumonia/metabolismo , Remodelação das Vias Aéreas , Células Epiteliais Alveolares/metabolismo , Animais , Displasia Broncopulmonar/metabolismo , Estudos de Casos e Controles , Catepsina G/metabolismo , Modelos Animais de Doenças , Proteína Forkhead Box M1 , Fatores de Transcrição Forkhead/genética , Humanos , Hiperóxia/metabolismo , Hiperóxia/fisiopatologia , Recém-Nascido , Pulmão/patologia , Pulmão/fisiopatologia , Lesão Pulmonar/etiologia , Lesão Pulmonar/patologia , Lesão Pulmonar/fisiopatologia , Macrófagos/metabolismo , Camundongos Knockout , Mieloblastina/metabolismo , Neutrófilos/metabolismo , Peroxidase/metabolismo , Pneumonia/etiologia , Pneumonia/patologia , Pneumonia/fisiopatologia
9.
Int J Clin Pharmacol Ther ; 53(7): 593-602, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26042485

RESUMO

OBJECTIVE: Budesonide formoterol (BF) Spiromax® is a breath-actuated dry-powder inhaler designed to deliver similar combinations of budesonide and formoterol as Symbicort® Turbohaler®. We performed two studies to demonstrate pharmacokinetic (PK) equivalence of BF Spiromax with BF Turbohaler. MATERIALS AND METHODS: Two single-center, open-label, randomized, 5-period crossover studies were performed. The first study compared BF Spiromax 160/4.5 µg with BF Turbohaler 200/6 µg, while the second study compared BF Spiromax 320/9 µg with BF Turbohaler 400/12 µg. All treatments were administered with and without charcoal. PK parameters were calculated by measuring plasma drug concentrations from blood samples taken pre-dose and up to 24 hours post-dose. RESULTS: In each study, 90 healthy volunteers were randomized. Bioequivalence of BF Spiromax with BF Turbohaler was demonstrated for budesonide and formoterol (AUC0-t and Cmax (90% confidence intervals of the geometric mean between-device ratios for both parameters were within the predefined range of 0.80-1.25 in both studies)). Equivalence was observed without use of charcoal (overall absorption post-inhalation) and with charcoal (pulmonary absorption). There were no major differences between treatments in tmax for either budesonide or formoterol. All study treatments were well tolerated (one treatment-emergent adverse event (TEAE) in the medium-dose study and four TEAEs in the high-dose study). CONCLUSIONS: These studies indicate that BF Spiromax (±charcoal block) is bioequivalent to BF Turbohaler with respect to the PK parameters assessed. Single doses of BF Spiromax were well tolerated; the overall safety profile of BF Spiromax and BF Turbohaler was similar.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Agonistas de Receptores Adrenérgicos beta 2/farmacocinética , Broncodilatadores/administração & dosagem , Broncodilatadores/farmacocinética , Budesonida/administração & dosagem , Budesonida/farmacocinética , Carvão Vegetal , Inaladores de Pó Seco , Etanolaminas/administração & dosagem , Etanolaminas/farmacocinética , Glucocorticoides/administração & dosagem , Glucocorticoides/farmacocinética , Administração por Inalação , Agonistas de Receptores Adrenérgicos beta 2/efeitos adversos , Agonistas de Receptores Adrenérgicos beta 2/sangue , Adulto , Broncodilatadores/efeitos adversos , Broncodilatadores/sangue , Budesonida/efeitos adversos , Budesonida/sangue , Estudos Cross-Over , Combinação de Medicamentos , Desenho de Equipamento , Etanolaminas/efeitos adversos , Etanolaminas/sangue , Feminino , Fumarato de Formoterol , Glucocorticoides/efeitos adversos , Glucocorticoides/sangue , Voluntários Saudáveis , Humanos , Masculino , Equivalência Terapêutica , Adulto Jovem
10.
J Transl Med ; 12: 181, 2014 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-24962100

RESUMO

BACKGROUND: Therapeutic hypothermia is a treatment modality that is increasingly used to improve clinical neurological outcomes for ischemia-reperfusion injury-mediated diseases. Antibody-initiated classical complement pathway activation has been shown to contribute to ischemia-reperfusion injury in multiple disease processes. However, how therapeutic hypothermia affects complement activation is unknown. Our goal was to measure the independent effect of temperature on complement activation, and more specifically, examine the relationship between clinical hypothermia temperatures (31-33°C), and complement activation. METHODS: Antibody-sensitized erythrocytes were used to assay complement activation at temperatures ranging from 0-41°C. Individual complement pathway components were assayed by ELISA, Western blot, and quantitative dot blot. Peptide Inhibitor of complement C1 (PIC1) was used to specifically inhibit activation of C1. RESULTS: Antibody-initiated complement activation resulting in eukaryotic cell lysis was increased by 2-fold at 31°C compared with 37°C. Antibody-initiated complement activation in human serum increased as temperature decreased from 37°C until dramatically decreasing at 13°C. Quantitation of individual complement components showed significantly increased activation of C4, C3, and C5 at clinical hypothermia temperatures. In contrast, C1s activation by heat-aggregated IgG decreased at therapeutic hypothermia temperatures consistent with decreased enzymatic activity at lower temperatures. However, C1q binding to antibody-coated erythrocytes increased at lower temperatures, suggesting that increased classical complement pathway activation is mediated by increased C1 binding at therapeutic hypothermia temperatures. PIC1 inhibited hypothermia-enhanced complement-mediated cell lysis at 31°C by up to 60% (P = 0.001) in a dose dependent manner. CONCLUSIONS: In summary, therapeutic hypothermia temperatures increased antibody-initiated complement activation and eukaryotic cell destruction suggesting that the benefits of therapeutic hypothermia may be mediated via other mechanisms. Antibody-initiated complement activation has been shown to contribute to ischemia-reperfusion injury in several animal models, suggesting that for diseases with this mechanism hypothermia-enhanced complement activation may partially attenuate the benefits of therapeutic hypothermia.


Assuntos
Ativação do Complemento , Hipotermia/fisiopatologia , Temperatura , Ensaio de Imunoadsorção Enzimática , Humanos , Hipotermia/metabolismo , Hipotermia/patologia , Ligação Proteica
11.
Transfusion ; 54(11): 2892-900, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24806146

RESUMO

BACKGROUND: Prevention of acute hemolytic transfusion reactions is a worldwide concern. The objective of this study was to develop a simple rat model of complement-mediated acute intravascular hemolysis. STUDY DESIGN AND METHODS: Human AB red blood cells (RBCs) were incubated with complement-sufficient or complement-deficient Wistar rat serum (WRS) in the presence and absence of human RBC antibody in vitro to elucidate the mechanism of hemolysis. To study the role of complement in acute intravascular hemolysis in vivo, Wistar rats were treated either with or without cobra venom factor (CVF) to deplete complement activity. Human AB RBCs were then injected into both groups of rats, followed by serial blood draws up to 2 hours. Venous blood clearance and lysis of transfused RBCs at each time point were measured by flow cytometry and spectrophotometry. RBC sequestration was determined in the liver, spleen, and kidney by immunohistochemistry. RESULTS: In vitro incubation of human RBCs with WRS demonstrated that RBC lysis was mediated via the classical complement pathway and that hemolysis was antibody dependent. Transfusion of human RBCs into rats showed significantly less hemolysis in the CVF group versus untreated group. RBC sequestration in the spleen and liver 2 hours posttransfusion were not quantitatively different between the two groups. CONCLUSIONS: Given the much higher degree of similarity for rat and human complement compared to mice, this simple rat model is ideal for testing novel inhibitors of classical pathway activation for the prevention and treatment of acute intravascular hemolysis.


Assuntos
Proteínas do Sistema Complemento , Transfusão de Eritrócitos/efeitos adversos , Eritrócitos/metabolismo , Hemólise , Fígado/metabolismo , Baço/metabolismo , Doença Aguda , Animais , Inativadores do Complemento/farmacologia , Via Clássica do Complemento/efeitos dos fármacos , Modelos Animais de Doenças , Venenos Elapídicos/farmacologia , Eritrócitos/patologia , Humanos , Fígado/patologia , Camundongos , Ratos , Ratos Wistar , Especificidade da Espécie , Baço/patologia
12.
Clin Infect Dis ; 56(4): e40-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23166187

RESUMO

BACKGROUND: Deer tick virus (DTV) is a tick-borne flavivirus that has only recently been appreciated as a cause of viral encephalitis. We describe the clinical presentation of a patient who had DTV encephalitis diagnosed before death and survived for 8 months despite severe neurologic dysfunction. METHODS: Diagnosis was made from a cerebrospinal fluid specimen, using a flavivirus-specific polymerase chain-reaction assay followed by sequence confirmation, and the phylogeny was analyzed. Serologic testing, including plaque reduction neutralization testing, was also performed. RESULTS: Molecular analysis indicated that the virus was closely related to 2 strains of DTV that had been detected in Ixodes scapularis ticks from Massachusetts in 1996 and in the brain of a patient from New York in 2007. CONCLUSIONS: DTV encephalitis should be considered in the differential diagnosis of encephalitis in geographic areas that are endemic for Lyme disease.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Encefalite Transmitida por Carrapatos/líquido cefalorraquidiano , Ixodes , Idoso , Animais , Antibacterianos/uso terapêutico , Cefepima , Cefalosporinas/uso terapêutico , Diagnóstico Diferencial , Encefalite Transmitida por Carrapatos/tratamento farmacológico , Evolução Fatal , Humanos , Imageamento por Ressonância Magnética , Masculino , New York , Filogenia , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Behav Brain Res ; 437: 114119, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36162642

RESUMO

Neonatal hypoxic ischemic encephalopathy (HIE) is a neurological disease caused by restricted oxygen and blood flow to the brain at or around the time of birth. Long term cognitive and motor sequelae are common and demonstrate sexual dimorphism in animal studies. Therapeutic hypothermia (TH) is the standard of care for HIE, but provides incomplete neuroprotection. Using the Vannucci model of neonatal HIE, term-equivalent 11-day old rat pups were subjected to mild-moderate hypoxic-ischemic injury (HII), and a subset of animals were treated with TH. Sex-dependent neuroprotection was measured with gross and fine motor control assays, and functional deficits detected with these assays were correlated to injury in specific brain structures. At the equivalent of human adolescence and adulthood (P51-89), accelerod and beam walking tests were used to assess gross motor function, and string-pulling and food handling tests were used to assess fine motor function. At necropsy (P94-97), brain lesions were primarily focused to the posterior cerebrum and characterized by variable reduction in cortical, thalamic and hippocampal regions and glial scarring. Gross motor impairment was detected in male rats with untreated and TH-treated HIE in the accelerod test, but beam walk test data was confounded by the lower body mass of untreated male rats. HIE animals of both sexes demonstrated deficit in the forelimb contralateral to ischemic surgery, observed as unilaterally impaired food handling behaviors, and in string pulling as decreased string contacts and increased in bracing behavior. However, kinematic analyses revealed sex-specific decreases in peak speeds in string reaching and pulling movements. In both sexes, treatment with TH improved body mass, some measures of contralateral forelimb impairment, and the severity of brain lesions to levels not different to Sham surgery rats. Unique differences in behavior following TH were observed in female rats, who took longer to consume food items but traversed beams and approached strings faster than untreated and Sham females. Future use of these motor assays may unravel the subtle, sex-specific differences in HIE outcomes and in developing a customized therapeutic approach to neonatal brain injury.


Assuntos
Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Adulto , Animais , Feminino , Humanos , Masculino , Ratos , Animais Recém-Nascidos , Hipóxia-Isquemia Encefálica/patologia , Neuroproteção
14.
Front Neurosci ; 15: 616734, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33642979

RESUMO

OBJECTIVE: Complement activation is instrumental in the pathogenesis of Hypoxic-ischemic encephalopathy (HIE), a significant cause of neonatal mortality and disability worldwide. Therapeutic hypothermia (HT), the only available treatment for HIE, only modestly improves outcomes. Complement modulation as a therapeutic adjunct to HT has been considered, but is challenging due to the wide-ranging role of the complement system in neuroinflammation, homeostasis and neurogenesis in the developing brain. We sought to identify potential therapeutic targets by measuring the impact of treatment with HT on complement effector expression in neurons and glia in neonatal HIE, with particular emphasis on the interactions between microglia and C1q. METHODS: The Vannucci model was used to induce HIE in term-equivalent rat pups. At P10-12, pups were randomly assigned to three different treatment groups: Sham (control), normothermia (NT), and hypothermia (HT) treatment. Local and systemic complement expression and neuronal apoptosis were measured by ELISA, TUNEL and immunofluorescence labeling, and differences compared between groups. RESULTS: Treatment with HT is associated with decreased systemic and microglial expression of C1q, decreased systemic C5a levels, and decreased microglial and neuronal deposition of C3 and C9. The effect of HT on cytokines was variable with decreased expression of pro and anti-inflammatory effectors. HT treatment was associated with decreased C1q binding on cells undergoing apoptosis. CONCLUSION: Our data demonstrate the extreme complexity of the immune response in neonatal HIE. We propose modulation of downstream effectors C3a and C5a as a therapeutic adjunct to HT to enhance neuroprotection in the developing brain.

15.
Brachytherapy ; 20(3): 631-637, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33642174

RESUMO

PURPOSE: The noninvasive image-guided breast brachytherapy (NIBB) technique is a novel noninvasive yet targeted method for accelerated partial breast irradiation. We established a multi-institutional registry to evaluate the toxicity and efficacy of this technique across various practice settings. METHODS AND MATERIALS: Institutions using the NIBB technique were invited to participate. Data for acute/late toxicity, cosmetic outcome, and tumor recurrence were collected. Toxicity and cosmetic outcome were graded based on the Common Terminology Criteria for Adverse Events version 3.0 and NRG/Radiation Therapy Oncology Group scale, respectively. Treatment variables were analyzed for association with outcomes. RESULTS: A total of 252 patients from eight institutions were analyzed. The median age was 69 years. The mean tumor size was 1.1 cm (0.1-4.0 cm). Treatment was delivered 10 fractions (34-36 Gy) in 75% and five fractions (28.5 Gy) in 22%. B.i.d. fractionation was used in 9%. Acute radiation dermatitis was Grade 0-1, 2, and 3 in 77%, 19%, and 4%, respectively. One hundred ninety-one patients with a median followup of 18 months (4-72 months) were evaluable for late outcomes. Late toxicity Grades 2 and 3 were observed in 8.8% and 1%, respectively. Cosmetic outcome was excellent, good, and fair/poor in 62%, 36%, and 2%, respectively. B.i.d. fractionation was associated with higher acute and late toxicity. Second-generation applicators were associated with lower late toxicity and better cosmetic outcome. Actuarial freedom from ipsilateral breast tumor recurrence and true recurrence were 98.3% and 98.3% at 2 years and 90.9% and 95.4% at 5 years, respectively. CONCLUSIONS: Accelerated partial breast irradiation using NIBB was well tolerated with a low rate of acute and late toxicity across various practice settings. Ipsilateral breast tumor recurrence and cosmetic outcomes were favorable. b.i.d. fractionation was associated with higher toxicity. Longer followup is needed to confirm late endpoints.


Assuntos
Braquiterapia , Neoplasias da Mama , Idoso , Braquiterapia/métodos , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Mastectomia Segmentar , Recidiva Local de Neoplasia/radioterapia , Dosagem Radioterapêutica , Sistema de Registros , Resultado do Tratamento
16.
Pediatr Res ; 68(3): 210-5, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20703142

RESUMO

Monocyte chemoattractant proteins (MCP-1 and MCP-2) mediate monocyte and T-lymphocyte chemotaxis, and IL-1 contributes to the pathogenesis of chorioamnionitis-induced lung inflammation and fetal inflammatory responses. We tested the hypothesis that IL-1 mediates the systemic and pulmonary induction of MCP-1 and MCP-2 in response to lipopolysaccharide (LPS)-induced chorioamnionitis. MCP-1 mRNA, MCP-2 mRNA, and MCP-1 protein expression were measured in two models: 1) intra-amniotic LPS and 2) intra-amniotic recombinant sheep IL-1alpha given at varying intervals before preterm delivery at 124 d GA. Intra-amniotic LPS or IL-1alpha induced MCP-1 mRNA and protein and MCP-2 mRNA in fetal lung many fold at 1-2 d. LPS induced intense MCP-1 expression in subepithelial mesenchymal cells and interstitial inflammatory cells in the lung. Inhibition of IL-1 signaling with recombinant human IL-1 receptor antagonist (rhIL-1ra) did not attenuate LPS induced increase in MCP-1 or MCP-2 expression. MCP-1 and MCP-2 were not induced in liver or chorioamnion, but MCP-1 increased in cord plasma. LPS or IL-1 can induce robust expression of MCP-1 or MCP-2 in the fetal lung. LPS induction of MCP-1 is not IL-1 dependent in fetal sheep. MCP-1 and MCP-2 may be significant contributors to fetal inflammation.


Assuntos
Quimiotaxia/fisiologia , Corioamnionite/induzido quimicamente , Corioamnionite/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Pulmão/metabolismo , Proteínas Quimioatraentes de Monócitos/metabolismo , RNA Mensageiro/metabolismo , Análise de Variância , Animais , Membranas Extraembrionárias/metabolismo , Feminino , Feto/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Interleucina-1/metabolismo , Lipopolissacarídeos/toxicidade , Fígado/metabolismo , Proteínas Quimioatraentes de Monócitos/sangue , Gravidez , Nascimento Prematuro/metabolismo , Receptores de Interleucina-1/antagonistas & inibidores , Ovinos , Austrália Ocidental
17.
J Perinatol ; 39(1): 54-62, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30348960

RESUMO

OBJECTIVE: Changes in cerebrovascular hemodynamics associated with head position may be important in the pathogenesis of periventricular-intraventricular hemorrhage (PIVH) in premature infants. This study evaluated the effect of elevated midline head positioning on cardiopulmonary function and the incidence of PIVH. STUDY DESIGN: ELBW infants were randomized to FLAT (flat, supine) or ELEV (supine, bed elevated 30 degrees) for 96 h. Cardiopulmonary function, complications of prematurity, and the occurrence of PIVH were documented. RESULTS: Infants were randomized into FLAT (n = 90) and ELEV groups (n = 90). No significant differences were seen in the incidence of BPD or other respiratory complications. The ELEV group developed significantly fewer grade 4 hemorrhages (p = 0.036) and survival to discharge was significantly higher in the ELEV group (p = 0.037). CONCLUSIONS: Managing ELBW infants in an elevated midline head position for the first 4 days of life appears safe and may decrease the likelihood of severe PIVH and improve survival.


Assuntos
Hemorragia Cerebral , Ventrículos Cerebrais , Circulação Cerebrovascular/fisiologia , Doenças do Prematuro , Movimentação e Reposicionamento de Pacientes , Posicionamento do Paciente , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/terapia , Ventrículos Cerebrais/irrigação sanguínea , Ventrículos Cerebrais/diagnóstico por imagem , Feminino , Idade Gestacional , Cabeça , Humanos , Incidência , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Recém-Nascido , Doenças do Prematuro/diagnóstico , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/etiologia , Doenças do Prematuro/terapia , Terapia Intensiva Neonatal/métodos , Masculino , Movimentação e Reposicionamento de Pacientes/efeitos adversos , Movimentação e Reposicionamento de Pacientes/métodos , Posicionamento do Paciente/efeitos adversos , Posicionamento do Paciente/métodos , Resultado do Tratamento , Ultrassonografia/métodos
19.
Neuromuscul Disord ; 18(7): 561-4, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18579382

RESUMO

In this study, we describe the association between Duchenne muscular dystrophy (DMD) and symptomatic nephrolithiasis. The DMD patients were matched to non-ambulatory control patients with non-DMD neurological diagnoses via retrospective chart review. All patients with DMD and symptomatic nephrolithiasis were over 20 years old. We found that six of the 29 at-risk DMD patients had nephrolithiasis (20.7%) while only one of the 68 control patients had nephrolithiasis (1.5%) (p<0.0001). Controlling for duration of immobilization with stratified analysis, the risk ratio for nephrolithiasis among DMD patients compared with controls was 9.94. Using rate-based estimates of renal stone development per 10,000 patient-years, the ratio of stone development among DMD patients compared with controls was 18.5. On logistic regression analysis, the corrected odds ratio for nephrolithiasis comparing DMD patients to controls was 14.26. We conclude that, in our study group, DMD was an independent risk factor for symptomatic nephrolithiasis.


Assuntos
Distrofia Muscular de Duchenne/complicações , Nefrolitíase/complicações , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Razão de Chances , Estudos Retrospectivos
20.
J Asthma ; 44(8): 629-33, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17943573

RESUMO

Coexisting asthma and allergic rhinitis (AR) are often treated with both intranasal and inhaled corticosteroids. This study investigated whether intranasal ciclesonide 200 microg once daily has an additional effect on cortisol suppression when coadministered with inhaled hydrofluoroalkane-beclomethasone dipropionate (HFA-BDP). Adult patients (n = 150) with perennial AR received HFA-BDP 320 microg twice daily and placebo once daily during a run-in period. Patients were then randomized to ciclesonide or placebo and HFA-BDP (43 days). A single 2-mg dose of dexamethasone was administered on the last treatment day. Plasma cortisol decreased by 67.8 microg x h/dL (p < 0.001) during the run-in period. When ciclesonide was added, the change in mean plasma cortisol was similar for ciclesonide and placebo (8.5 microg x h/dL and 1.0 microg x h/dL, respectively). Dexamethasone decreased mean plasma cortisol (p < 0.001), demonstrating that further cortisol suppression was possible. This study suggests that intranasal ciclesonide can be used with an inhaled corticosteroid without increased cortisol suppression.


Assuntos
Antialérgicos/administração & dosagem , Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Beclometasona/administração & dosagem , Hidrocortisona/sangue , Pregnenodionas/administração & dosagem , Rinite Alérgica Perene/tratamento farmacológico , Administração por Inalação , Administração Intranasal , Adolescente , Adulto , Antialérgicos/efeitos adversos , Antiasmáticos/efeitos adversos , Asma/sangue , Asma/complicações , Beclometasona/efeitos adversos , Método Duplo-Cego , Humanos , Hidrocortisona/urina , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Pessoa de Meia-Idade , Cooperação do Paciente , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Pregnenodionas/efeitos adversos , Rinite Alérgica Perene/sangue , Rinite Alérgica Perene/complicações
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA