RESUMO
BACKGROUND: Fibroblast growth factor receptor-3 (FGFR3) gain-of-function mutations are linked to achondroplasia. Infigratinib, a FGFR1-3 tyrosine kinase inhibitor, improves skeletal growth in an achondroplasia mouse model. FGFs and their receptors have critical roles in developing teeth, yet effects of infigratinib on tooth development have not been assessed. Dentoalveolar and craniofacial phenotype of Wistar rats dosed with low (0.1 mg/kg) and high (1.0 mg/kg) dose infigratinib were evaluated using micro-computed tomography, histology, and immunohistochemistry. RESULTS: Mandibular third molars were reduced in size and exhibited aberrant crown and root morphology in 100% of female rats and 80% of male rats at high doses. FGFR3 and FGF18 immunolocalization and extracellular matrix protein expression were unaffected, but cathepsin K (CTSK) was altered by infigratinib. Cranial vault bones exhibited alterations in dimension, volume, and density that were more pronounced in females. In both sexes, interfrontal sutures were significantly more patent with high dose vs vehicle. CONCLUSIONS: High dose infigratinib administered to rats during early stages affects dental and craniofacial development. Changes in CTSK from infigratinib in female rats suggest FGFR roles in bone homeostasis. While dental and craniofacial disruptions are not expected at therapeutic doses, our findings confirm the importance of dental monitoring in clinical studies.
Assuntos
Acondroplasia , Camundongos , Masculino , Ratos , Feminino , Animais , Microtomografia por Raio-X , Ratos Wistar , Receptores de Fatores de Crescimento de Fibroblastos/genéticaAssuntos
Morte Encefálica , Hipotálamo , Humanos , Morte Encefálica/diagnóstico , Hipotálamo/diagnóstico por imagem , Encéfalo , CabeçaRESUMO
OBJECTIVE: To examine the frequency and association of neck pain symptoms in patients with a concussion. STUDY SETTING AND PARTICIPANTS: Three-hundred and thirty-one consecutively enrolled patients aged 9 to 68 years with a diagnosed concussion 1 to 384 days post-injury were enrolled at a concussion clinic from a single integrated healthcare system in Western Pennsylvania between 2019 and 2021. DESIGN: Retrospective cohort analysis of prospectively collected concussion screening tool intake survey responses and clinical outcomes data. The primary outcome was self-reported neck pain or difficulty with neck movement on the Concussion Clinical Profiles Screening (CP Screen) tool, recovery time, and incidence of treatment referral. Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) composite scores, Vestibular/Ocular Motor Screening (VOMS) item scores, type and severity of neck symptoms, mechanism of injury, time from injury to clinic presentation, medical history, and concussion symptom profile were secondary outcomes. RESULTS: Of the 306 consecutively enrolled eligible patients in the registry, 145 (47%) reported neck pain, 68 (22.2%) reported difficulty moving their neck, and 146 (47.7%) reported either symptom. A total of 47 (15.4%) participants reported more severe neck symptoms, and this group took longer to recover (40 ± 27 days) than those not reporting neck symptoms (30 ± 28 days; U = 8316, P < .001). Stepwise logistic regression predicting more severe neck symptoms was significant (Nagelkerke R2 = 0.174, χ 2 = 9.315, P = .316) with older age ( P = .019) and mechanism of injury including motor vehicle collisions (MVCs) ( P = .047) and falls ( P = .044) as risk factors. MVCs and falls were associated with over 4 times and 2 times greater risk, respectively, for reporting more severe neck symptoms. CONCLUSION: Neck pain and stiffness symptoms are common in patients with a concussion following high-energy mechanisms of injury including MVCs or falls from height. These symptoms are associated with prolonged recovery. Providers should evaluate neck symptoms and consider targeted treatment strategies to limit their effects in patients with a concussion.
Assuntos
Traumatismos em Atletas , Concussão Encefálica , Síndrome Pós-Concussão , Humanos , Traumatismos em Atletas/diagnóstico , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/complicações , Estudos Retrospectivos , Cervicalgia/diagnóstico , Cervicalgia/epidemiologia , Cervicalgia/etiologia , Concussão Encefálica/diagnóstico , Concussão Encefálica/epidemiologia , Concussão Encefálica/complicações , Testes Neuropsicológicos , Síndrome Pós-Concussão/diagnóstico , Síndrome Pós-Concussão/epidemiologia , Síndrome Pós-Concussão/etiologiaRESUMO
Recently determined structures of class C G protein-coupled receptors (GPCRs) revealed the location of allosteric binding sites and opened new opportunities for the discovery of novel modulators. In this work, molecular docking screens for allosteric modulators targeting the metabotropic glutamate receptor 5 (mGlu5) were performed. The mGlu5 receptor is activated by the main excitatory neurotransmitter of the nervous central system, L-glutamate, and mGlu5 receptor activity can be allosterically modulated by negative or positive allosteric modulators. The mGlu5 receptor is a promising target for the treatment of psychiatric and neurodegenerative diseases, and several allosteric modulators of this GPCR have been evaluated in clinical trials. Chemical libraries containing fragment- (1.6 million molecules) and lead-like (4.6 million molecules) compounds were docked to an allosteric binding site of mGlu5 identified in X-ray crystal structures. Among the top-ranked compounds, 59 fragments and 59 lead-like compounds were selected for experimental evaluation. Of these, four fragment- and seven lead-like compounds were confirmed to bind to the allosteric site with affinities ranging from 0.43 to 8.6 µM, corresponding to a hit rate of 9%. The four compounds with the highest affinities were demonstrated to be negative allosteric modulators of mGlu5 signaling in functional assays. The results demonstrate that virtual screens of fragment- and lead-like chemical libraries have complementary advantages and illustrate how access to high-resolution structures of GPCRs in complex with allosteric modulators can accelerate lead discovery.
Assuntos
Receptor de Glutamato Metabotrópico 5 , Bibliotecas de Moléculas Pequenas , Receptor de Glutamato Metabotrópico 5/metabolismo , Regulação Alostérica , Simulação de Acoplamento Molecular , Bibliotecas de Moléculas Pequenas/farmacologia , Ligantes , Ácido Glutâmico , Sítio Alostérico , Receptores Acoplados a Proteínas GRESUMO
BACKGROUND: Repetitive, highly elevated blood alcohol (ethanol) concentrations (BACs) of 350 to 450 mg/dl over several days cause brain neurodegeneration and coincident neuroinflammation in adult rats localized in the hippocampus (HC), temporal cortex (especially the entorhinal cortex; ECX), and olfactory bulb (OB). The profuse neuroinflammation involves microgliosis, increased proinflammatory cytokines, and elevations of Ca+2 -dependent phospholipase A2 (cPLA2) and secretory PLA2 (sPLA2), which both mobilize proinflammatory ω-6 arachidonic acid (ARA). In contrast, Ca+2 -independent PLA2 (iPLA2) and anti-inflammatory ω-3 docosahexaenoic acid (DHA), a polyunsaturated fatty acid regulated primarily by iPLA2, are diminished. Furthermore, supplemented DHA exerts neuroprotection. Given uncertainties about the possible effects of lower circulating BACs that are common occurring during short- term binges, we examined how moderate BACs affected the above inflammatory events, and the impact of supplemented DHA. METHODS AND RESULTS: Young adult male rats sustaining upper-moderate BACs (~150 mg/dl) from once-daily alcohol intubations were sacrificed with appropriate controls after 1 week. The HC, ECX and OB were quantitatively examined using immunoblotting, neurodegeneration staining, and lipidomics assays. Whereas neurodegeneration, increases in cPLA2 IVA, sPLA2 IIA, and ARA, and microglial activation were not detected, the HC and ECX regions demonstrated significantly reduced iPLA2 levels. Levels of DHA and synaptamide, its anti-inflammatory N-docosahexaenoylethanolamide derivative, also were lower in HC, and DHA supplementation prevented the iPLA2 decrements in HC. Additionally, adult mice maintaining upper-moderate BACs from limited alcohol binges had reduced midbrain iPLA2 levels. CONCLUSIONS: The apparently selective depletion by moderate BACs of the metabolically linked anti-inflammatory triad of hippocampal iPLA2, DHA, and synaptamide, and of iPLA2 in the ECX, potentially indicates an unappreciated deficit in brain anti-inflammatory reserve that may be a harbinger of regional neurovulnerability.
Assuntos
Anti-Inflamatórios/farmacologia , Etanol/farmacologia , Etanolaminas/metabolismo , Fosfolipases A2 Independentes de Cálcio/farmacologia , Fosfolipases A2 Citosólicas/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Fosfolipases A2/metabolismo , RatosRESUMO
Some patients who have been diagnosed as "dead by neurologic criteria" continue to exhibit certain brain functions, most commonly, neuroendocrine functions. In this chapter, we review the pathophysiology of brain death that can lead either to neuroendocrine failure or to preserved neuroendocrine functioning. We review the evidence on continued hypothalamic functioning in patients who have been declared "brain dead," examine potential mechanisms that would explain these findings, and discuss how these findings create additional confounds for brain death testing. We conclude by reviewing the evidence for the management of hypothalamic-pituitary failure in the setting of brain death and organ transplantation.
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Morte Encefálica , Transplante de Órgãos , Morte Encefálica/diagnóstico , Humanos , Hipotálamo , Sistemas NeurossecretoresRESUMO
Psoriasis is an inflammatory autoimmune disease of the skin and nails, causing debilitating pain and having an adverse effect on the patients' life. Typical treatment regimens involve topical and systemic therapies in combination with phototherapy. However, patients with extensive, chronic disease may encounter treatment resistance, with limited or no success of these therapies. Radiation therapy (RT) has been shown to be an effective treatment for benign skin lesions; however, recommended dose, fractionation and long-term follow-up is not well established within the literature making clinical implementation challenging. Furthermore, RT may induce the Koebner Phenomenon, exacerbating the disease. This case study presents a patient with chronic hyperkeratotic palmoplantar psoriasis who was offered RT as a last resort. A total dose of 6Gy was delivered using photons and superficial energies. Significant reduction in extent of disease was seen as a result, with the patient no longer wheelchair-bound and able to mobilise with minimal discomfort. This case is a single example of RT as a successful treatment for chronic palmoplantar psoriasis; however, a larger sample size and clinical trial is needed to ascertain dose and fractionation for optimal long-term control. Implementation of such treatments within departments invites clinicians to further develop RT practices and provide much needed relief to a new cohort of patients with non-malignant conditions.
Assuntos
Psoríase , Doença Crônica , Humanos , Fototerapia , Psoríase/radioterapia , Resultado do TratamentoRESUMO
Autosomal dominant hypocalcemia type 1 (ADH1) is a rare form of hypoparathyroidism caused by heterozygous, gain-of-function mutations of the calcium-sensing receptor gene (CAR). Individuals are hypocalcemic with inappropriately low parathyroid hormone (PTH) secretion and relative hypercalciuria. Calcilytics are negative allosteric modulators of the extracellular calcium receptor (CaR) and therefore may have therapeutic benefits in ADH1. Five adults with ADH1 due to four distinct CAR mutations received escalating doses of the calcilytic compound NPSP795 (SHP635) on 3 consecutive days. Pharmacokinetics, pharmacodynamics, efficacy, and safety were assessed. Parallel in vitro testing with subject CaR mutations assessed the effects of NPSP795 on cytoplasmic calcium concentrations (Ca2+i ), and ERK and p38MAPK phosphorylation. These effects were correlated with clinical responses to administration of NPSP795. NPSP795 increased plasma PTH levels in a concentration-dependent manner up to 129% above baseline (p = 0.013) at the highest exposure levels. Fractional excretion of calcium (FECa) trended down but not significantly so. Blood ionized calcium levels remained stable during NPSP795 infusion despite fasting, no calcitriol supplementation, and little calcium supplementation. NPSP795 was generally safe and well-tolerated. There was significant variability in response clinically across genotypes. In vitro, all mutant CaRs were half-maximally activated (EC50 ) at lower concentrations of extracellular calcium (Ca2+o ) compared to wild-type (WT) CaR; NPSP795 exposure increased the EC50 for all CaR activity readouts. However, the in vitro responses to NPSP795 did not correlate with any clinical parameters. NPSP795 increased plasma PTH levels in subjects with ADH1 in a dose-dependent manner, and thus, serves as proof-of-concept that calcilytics could be an effective treatment for ADH1. Albeit all mutations appear to be activating at the CaR, in vitro observations were not predictive of the in vivo phenotype or the response to calcilytics, suggesting that other parameters impact the response to the drug. © 2019 American Society for Bone and Mineral Research.
Assuntos
Compostos de Cálcio/uso terapêutico , Hipercalciúria/tratamento farmacológico , Hipocalcemia/tratamento farmacológico , Hipoparatireoidismo/congênito , Adulto , Área Sob a Curva , Compostos de Cálcio/efeitos adversos , Compostos de Cálcio/farmacocinética , Linhagem Celular , Feminino , Genótipo , Humanos , Hipercalciúria/genética , Hipocalcemia/genética , Hipoparatireoidismo/tratamento farmacológico , Hipoparatireoidismo/genética , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto JovemRESUMO
American archeology has long been polarized over the issue of a human presence in the Western Hemisphere earlier than Clovis. As evidence of early sites across North and South America continues to emerge, stone tool assemblages appear more geographically and temporally diverse than traditionally assumed. Within this new framework, the prevailing models of Clovis origins and the peopling of the Americas are being reevaluated. This paper presents age estimates from a series of alluvial sedimentary samples from the earliest cultural assemblage at the Gault Site, Central Texas. The optically stimulated luminescence age estimates (~16 to 20 thousand years ago) indicate an early human occupation in North America before at least ~16 thousand years ago. Significantly, this assemblage exhibits a previously unknown, early projectile point technology unrelated to Clovis. Within a wider context, this evidence suggests that Clovis technology spread across an already regionalized, indigenous population.
Assuntos
Arqueologia , Fósseis/história , História Antiga , Atividades Humanas/história , Humanos , América do Norte , Tecnologia , TexasRESUMO
BACKGROUND: Sodium glucose cotransporter-2 (SGLT2) inhibitors are the most recently approved class of drugs for type 2 diabetes and provide both glycemic efficacy and cardiovascular risk reduction. A number of safety issues have been identified, including treatment-emergent bone fractures. To understand the overall clinical profile, these safety issues must be balanced against an attractive efficacy profile. Our study was designed to investigate pathophysiological mechanisms mediating treatment-emergent adverse effects on bone health. METHODS: We conducted a single-blind randomized crossover study in hospitalized healthy adults (n = 25) receiving either canagliflozin (300 mg/d) or placebo for 5 days. The primary end-point was the drug-induced change in AUC for plasma intact fibroblast growth factor 23 (FGF23) immunoactivity between 24 and 72 hours. RESULTS: Canagliflozin administration increased placebo-subtracted mean levels of serum phosphorus (+16%), plasma FGF23 (+20%), and plasma parathyroid hormone (PTH) (+25%), while decreasing the level of 1,25-dihydroxyvitamin D (-10%). There was substantial interindividual variation in the magnitude of each of these pharmacodynamic responses. The increase in plasma FGF23 was correlated with the increase in serum phosphorus, and the decrease in plasma 1,25-dihydroxyvitamin D was correlated with the increase in plasma FGF23. CONCLUSIONS: Canagliflozin induced a prompt increase in serum phosphorus, which triggers downstream changes in FGF23, 1,25-dihydroxyvitamin D, and PTH, with potential to exert adverse effects on bone health. These pharmacodynamic data provide a foundation for future research to elucidate pathophysiological mechanisms of adverse effects on bone health, with the objective of devising therapeutic strategies to mitigate the drug-associated fracture risk. TRIAL REGISTRATION: ClinicalTrial.gov (NCT02404870). FUNDING: Supported by the Intramural Program of NIDDK.
Assuntos
Canagliflozina/efeitos adversos , Fatores de Crescimento de Fibroblastos/sangue , Fraturas Ósseas/induzido quimicamente , Adulto , Canagliflozina/administração & dosagem , Canagliflozina/farmacologia , Estudos Cross-Over , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/efeitos dos fármacos , Fraturas Ósseas/fisiopatologia , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Fósforo/sangue , Placebos/administração & dosagem , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Vitamina D/análogos & derivados , Vitamina D/sangueRESUMO
The Uniform Determination of Death Act (UDDA) states that an individual is dead when "all functions of the entire brain" have ceased irreversibly. However, it has been questioned whether some functions of the hypothalamus, particularly osmoregulation, can continue after the clinical diagnosis of brain death (BD). In order to learn whether parts of the hypothalamus can continue to function after the diagnosis of BD, we performed 2 separate systematic searches of the MEDLINE database, corresponding to the functions of the posterior and anterior pituitary. No meta-analysis is possible due to nonuniformity in the clinical literature. However, some modest generalizations can reasonably be drawn from a narrative review and from anatomic considerations that explain why these findings should be expected. We found evidence suggesting the preservation of hypothalamic function, including secretion of hypophysiotropic hormones, responsiveness to anterior pituitary stimulation, and osmoregulation, in a substantial proportion of patients declared dead by neurological criteria. We discuss several possible explanations for these findings. We conclude by suggesting that additional clinical research with strict inclusion criteria is necessary and further that a more nuanced and forthright public dialogue is needed, particularly since standard diagnostic practices and the UDDA may not be entirely in accord.
Assuntos
Dano Encefálico Crônico/patologia , Dano Encefálico Crônico/fisiopatologia , Morte Encefálica/fisiopatologia , Hormônios Hipotalâmicos/sangue , Hipotálamo/patologia , Hipófise/patologia , Hormônios Hipofisários/sangue , Morte Encefálica/patologia , Hormônio Liberador da Corticotropina/sangue , Hormônio Liberador de Gonadotropina/sangue , Hormônio Liberador de Hormônio do Crescimento/sangue , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Cuidados para Prolongar a VidaRESUMO
AIM: Chronic radiation injuries, although uncommon, are associated with poor quality of life in oncology patients. The present study assesses the efficacy and safety of hyperbaric oxygen therapy in the management of chronic radiation-induced tissue injuries. METHODS: A retrospective analysis was performed in 276 consecutive patients treated with hyperbaric oxygen therapy for chronic radiation-induced tissue injuries at the Hyperbaric Medicine Unit, Townsville, Queensland, between March 1995 and March 2008. Of these patients, 189 (68%) had complete follow-up data and were assessed. RESULTS: A total of 265 events of chronic radiation tissue injury were experienced by the 189 patients treated with hyperbaric oxygen therapy. Osteoradionecrosis prophylaxis due to radiation-induced dental disease had an overall response rate of 96% (P=0.00003; Wilcoxon matched-pairs signed-rank test). The overall response rates for established osteoradionecrosis of mandible, soft tissue necrosis of head and neck, and xerostomia were 86% (P=0.00001), 85% (P=0.002) and 64% (P=0.0001), respectively. The overall response rates for soft tissue necrosis at other sites, chronic radiation proctitis and hemorrhagic cystitis were 84% (P=0.03), 95% (P=0.0001) and 85% (P=0.03), respectively. The total complication rate after hyperbaric oxygen therapy was 15.9%, comprising reversible ear barotrauma (10.6%), reversible ocular barotrauma (4.2%), dental complications (0.5%) and myocardial infarction (0.5%). CONCLUSION: Our study demonstrates that hyperbaric oxygen therapy can be effectively used in a variety of chronic radiation-induced tissue injuries; its favorable risk profile suggests it should be considered for patients with radiation-induced tissue injuries.
Assuntos
Cistite/terapia , Oxigenoterapia Hiperbárica , Proctite/terapia , Qualidade de Vida , Lesões por Radiação/terapia , Radioterapia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Australásia/epidemiologia , Doença Crônica , Cistite/epidemiologia , Cistite/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/patologia , Neoplasias/radioterapia , Proctite/epidemiologia , Proctite/etiologia , Prognóstico , Lesões por Radiação/epidemiologia , Lesões por Radiação/etiologia , Estudos RetrospectivosRESUMO
Evidence that brain edema and aquaporin-4 (AQP4) water channels have roles in experimental binge ethanol-induced neurodegeneration has stimulated interest in swelling/edema-linked neuroinflammatory pathways leading to oxidative stress. We report here that neurotoxic binge ethanol exposure produces comparable significant effects in vivo and in vitro on adult rat brain levels of AQP4 as well as neuroinflammation-linked enzymes: key phospholipase A2 (PLA2) family members and poly (ADP-ribose) polymerase-1 (PARP-1). In adult male rats, repetitive ethanol intoxication (3 gavages/d for 4 d, â¼ 9 g/kg/d, achieving blood ethanol levels â¼ 375 mg/dl; "Majchrowicz" model) significantly increased AQP4, Ca+2-dependent PLA2 GIVA (cPLA2), phospho-cPLA2 GIVA (p-cPLA2), secretory PLA2 GIIA (sPLA2) and PARP-1 in regions incurring extensive neurodegeneration in this model--hippocampus, entorhinal cortex, and olfactory bulb--but not in two regions typically lacking neurodamage, frontal cortex and cerebellum. Also, ethanol reduced hippocampal Ca+2-independent PLA2 GVIA (iPLA2) levels and increased brain "oxidative stress footprints" (4-hydroxynonenal-adducted proteins). For in vitro studies, organotypic cultures of rat hippocampal-entorhinocortical slices of adult age (â¼ 60 d) were ethanol-binged (100 mM or â¼ 450 mg/dl) for 4 d, which augments AQP4 and causes neurodegeneration (Collins et al. 2013). Reproducing the in vivo results, cPLA2, p-cPLA2, sPLA2 and PARP-1 were significantly elevated while iPLA2 was decreased. Furthermore, supplementation with docosahexaenoic acid (DHA; 22:6n-3), known to quell AQP4 and neurodegeneration in ethanol-treated slices, blocked PARP-1 and PLA2 changes while counteracting endogenous DHA reduction and increases in oxidative stress footprints (3-nitrotyrosinated proteins). Notably, the PARP-1 inhibitor PJ-34 suppressed binge ethanol-dependent neurodegeneration, indicating PARP upstream involvement. The results with corresponding models support involvement of AQP4- and PLA2-associated neuroinflammatory pro-oxidative pathways in the neurodamage, with potential regulation by PARP-1 as well. Furthermore, DHA emerges as an effective inhibitor of these binge ethanol-dependent neuroinflammatory pathways as well as associated neurodegeneration in adult-age brain.
Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Córtex Entorrinal/efeitos dos fármacos , Etanol/efeitos adversos , Hipocampo/efeitos dos fármacos , Animais , Aquaporina 4/metabolismo , Ácidos Docosa-Hexaenoicos/uso terapêutico , Relação Dose-Resposta a Droga , Córtex Entorrinal/metabolismo , Hipocampo/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Fosfolipases A2/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
Chronic alcohol (ethanol) abuse causes neuroinflammation and brain damage that can give rise to alcoholic dementia. Insightfully, Dr. Albert Sun was an early proponent of oxidative stress as a key factor in alcoholism-related brain deterioration. In fact, oxidative stress has proven to be critical to the hippocampal and temporal cortical neurodamage resulting from repetitive "binge" alcohol exposure in adult rat models. Although the underlying mechanisms are uncertain, our immunoelectrophoretic and related assays in binge alcohol experiments in vivo (adult male rats) and in vitro (rat organotypic hippocampal-entorhinal cortical slice cultures) have implicated phospholipase A(2) (PLA(2))-activated neuroinflammatory pathways, release of pro-oxidative arachidonic acid (20:4 ω6), and elevated oxidative stress adducts (i.e., 4-hydroxynonenal-protein adducts). Also, significantly increased by the binge alcohol treatments was aquaporin-4 (AQP4), a water channel enriched in astrocytes that, when augmented, may trigger brain (esp. cellular) edema and neuroinflammation; of relevance, glial swelling is known to provoke increased PLA(2) activities or levels. Concomitant with PLA(2) activation, the results have further implicated binge alcohol-elevated poly (ADP-ribose) polymerase-1 (PARP-1), an oxidative stress-responsive DNA repair enzyme linked to parthanatos, a necrotic-like neuronal death process. Importantly, supplementation of the brain slice cultures with docosahexaenoic acid (22:6 ω3) exerted potent suppression of the induced changes in PLA(2) isoforms, AQP4, PARP-1 and oxidative stress footprints, and prevention of the binge alcohol neurotoxicity, by as yet unknown mechanisms. These neuroinflammatory findings from our binge alcohol studies and supportive rat binge studies in the literature are reviewed.
Assuntos
Ácidos Docosa-Hexaenoicos/uso terapêutico , Encefalite/metabolismo , Etanol , Estresse Oxidativo/efeitos dos fármacos , Fosfolipases A2/metabolismo , Animais , Aquaporina 4/metabolismo , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Encefalite/induzido quimicamente , Encefalite/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , RatosRESUMO
Tumor-induced osteomalacia (TIO) is a rare disorder of phosphate wasting due to fibroblast growth factor-23 (FGF23)-secreting tumors that are often difficult to locate. We present a systematic approach to tumor localization and postoperative biochemical changes in 31 subjects with TIO. All had failed either initial localization, or relocalization (in case of recurrence or metastases) at outside institutions. Functional imaging with ¹¹¹Indium-octreotide with single photon emission computed tomography (octreo-SPECT or SPECT/CT), and ¹8fluorodeoxyglucose positron emission tomography/CT (FDG-PET/CT) were performed, followed by anatomic imaging (CT, MRI). Selective venous sampling (VS) was performed when multiple suspicious lesions were identified or high surgical risk was a concern. Tumors were localized in 20 of 31 subjects (64.5%). Nineteen of 20 subjects underwent octreo-SPECT imaging, and 16 of 20 FDG-PET/CT imaging. Eighteen of 19 (95%) were positive on octreo-SPECT, and 14 of 16 (88%) on FDG-PET/CT. Twelve of 20 subjects underwent VS; 10 of 12 (83%) were positive. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were as follows: sensitivity = 0.95, specificity = 0.64, PPV = 0.82, and NPV = 0.88 for octreo-SPECT; sensitivity = 0.88, specificity = 0.36, PPV = 0.62, and NPV = 0.50 for FDG-PET/CT. Fifteen subjects had their tumor resected at our institution, and were disease-free at last follow-up. Serum phosphorus returned to normal in all subjects within 1 to 5 days. In 10 subjects who were followed for at least 7 days postoperatively, intact FGF23 (iFGF23) decreased to near undetectable within hours and returned to the normal range within 5 days. C-terminal FGF23 (cFGF23) decreased immediately but remained elevated, yielding a markedly elevated cFGF23/iFGF23 ratio. Serum 1,25-dihydroxyvitamin D3 (1,25D) rose and exceeded the normal range. In this systematic approach to tumor localization in TIO, octreo-SPECT was more sensitive and specific, but in many cases FDG-PET/CT was complementary. VS can discriminate between multiple suspicious lesions and increase certainty prior to surgery. Sustained elevations in cFGF23 and 1,25D were observed, suggesting novel regulation of FGF23 processing and 1,25D generation.
Assuntos
Neoplasias Ósseas , Calcitriol/sangue , Fatores de Crescimento de Fibroblastos/sangue , Proteínas de Neoplasias/sangue , Osteomalacia , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada de Emissão de Fóton Único , Adolescente , Adulto , Idoso , Neoplasias Ósseas/sangue , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/cirurgia , Raquitismo Hipofosfatêmico Familiar/sangue , Raquitismo Hipofosfatêmico Familiar/diagnóstico por imagem , Raquitismo Hipofosfatêmico Familiar/terapia , Feminino , Fator de Crescimento de Fibroblastos 23 , Fluordesoxiglucose F18/administração & dosagem , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Octreotida/análogos & derivados , Osteomalacia/sangue , Osteomalacia/diagnóstico por imagem , Osteomalacia/etiologia , Osteomalacia/cirurgia , Radiografia , Compostos Radiofarmacêuticos/administração & dosagem , Estudos RetrospectivosRESUMO
Repetitive binge intoxication with ethanol (alcohol) in adult rats, mimicking chronic ethanol abuse in alcoholics, causes trauma-like brain edema and relatively selective neurodegeneration of hippocampal dentate granule cells and pyramidal neurons in the temporal cortex (especially entorhinal cortex). We have now modeled the aspects of this type of acquired brain damage in vitro with rat entorhino-hippocampal slice cultures of adult brain age (62 ± 3 days). When sequentially treated (four 16-h overnight exposures) with 100 mM ethanol, the slices display elevated levels of aquaporin-4 (AQP4) water channels accompanied by significant neurodegeneration. Increased AQP4 has been associated with neuroinflammatory responses including edema, pro-inflammatory cytokine elevations, arachidonic acid release, and oxidative stress. Co-treatment of ethanol-binged slice cultures with docosahexaenoic acid (DHA), an omega-3 fatty acid known to suppress brain damage from other insults, prevents both the AQP4 elevations and the neurodamage. Surmising that AQP4 augmentation is a causative neuroinflammatory component in this model, we are investigating several possibilities to explain the protective actions of the omega-3 fatty acid. Since the worldwide incidence of cognitive dysfunction and dementia from ethanol abuse and alcoholism is not inconsequential, DHA supplementation with chronic alcoholics could emerge to be a rational approach to potentially lessening brain disabilities.
Assuntos
Aquaporina 4/antagonistas & inibidores , Consumo Excessivo de Bebidas Alcoólicas/prevenção & controle , Ácidos Docosa-Hexaenoicos/uso terapêutico , Etanol/toxicidade , Hipocampo/efeitos dos fármacos , Degeneração Neural/prevenção & controle , Fatores Etários , Animais , Aquaporina 4/metabolismo , Consumo Excessivo de Bebidas Alcoólicas/metabolismo , Consumo Excessivo de Bebidas Alcoólicas/patologia , Ácidos Docosa-Hexaenoicos/farmacologia , Etanol/administração & dosagem , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-DawleyRESUMO
Nitrogen-rich heterocyclic compounds have had a profound effect on human health because these chemical motifs are found in a large number of drugs used to combat a broad range of diseases and pathophysiological conditions. Advances in transition-metal-mediated cross-coupling have simplified the synthesis of such molecules; however, C-H functionalization of medicinally important heterocycles that does not rely on pre-functionalized starting materials is an underdeveloped area. Unfortunately, the innate properties of heterocycles that make them so desirable for biological applications--such as aqueous solubility and their ability to act as ligands--render them challenging substrates for direct chemical functionalization. Here we report that zinc sulphinate salts can be used to transfer alkyl radicals to heterocycles, allowing for the mild (moderate temperature, 50 °C or less), direct and operationally simple formation of medicinally relevant C-C bonds while reacting in a complementary fashion to other innate C-H functionalization methods (Minisci, borono-Minisci, electrophilic aromatic substitution, transition-metal-mediated C-H insertion and C-H deprotonation). We prepared a toolkit of these reagents and studied their reactivity across a wide range of heterocycles (natural products, drugs and building blocks) without recourse to protecting-group chemistry. The reagents can even be used in tandem fashion in a single pot in the presence of water and air.
Assuntos
Carbono/química , Hidrogênio/química , Ar , Alquilação , Produtos Biológicos/química , Desenho de Fármacos , Ligação de Hidrogênio , Indicadores e Reagentes/química , Metilação , Nitrogênio/química , Preparações Farmacêuticas/química , Ácidos Sulfínicos/química , Água , Zinco/químicaRESUMO
Clinical treatment pathways are useful to ensure that evidence-based medicine is consistently applied in hospital systems and have been shown to improve patient outcomes. Such pathways need to be regularly updated and revised by incorporating new evidence from clinical trials to ensure optimal clinical care. In 2011, we published the Columbia University Medical Center/New York Presbyterian Hospital - Clinical Pathways for Acute Coronary Syndromes and Chest Pain. This algorithm includes primary percutaneous coronary intervention for all patients with ST-segment elevation myocardial infarction and an early invasive approach for patients with non-ST-segment elevation myocardial infarction. Since our last chest pain algorithm update, the novel antiplatelet agent ticagrelor has been introduced in the United States, resulting in an important revision of our acute coronary syndrome clinical pathways. Herein, we present our updated chest pain algorithm and provide rationale for the changes that we have made to our protocol.
Assuntos
Síndrome Coronariana Aguda/terapia , Anticoagulantes/uso terapêutico , Dor no Peito/terapia , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea , Inibidores da Agregação Plaquetária/uso terapêutico , Síndrome Coronariana Aguda/complicações , Algoritmos , Dor no Peito/etiologia , Procedimentos Clínicos/normas , Eletrocardiografia , Medicina de Emergência Baseada em Evidências , HumanosRESUMO
Fibrous dysplasia (FD) is a skeletal disease caused by somatic activating mutations of the cyclic adenosine monophosphate (cAMP)-regulating protein, α-subunit of the Gs stimulatory protein (G(s) α). These mutations lead to replacement of normal bone by proliferative osteogenic precursors, resulting in deformity, fracture, and pain. Medical treatment has been ineffective in altering the disease course. Receptor activator of NF-κB ligand (RANKL) is a cell-surface protein involved in many cellular processes, including osteoclastogenesis, and is reported to be overexpressed in FD-like bone cells. Denosumab is a humanized monoclonal antibody to RANKL approved for treatment of osteoporosis and prevention of skeletal-related events from bone metastases. We present the case of a 9-year-old boy with severe FD who was treated with denosumab for a rapidly expanding femoral lesion. Immunohistochemical staining on a pretreatment bone biopsy specimen revealed marked RANKL expression. He was started on monthly denosumab, with an initial starting dose of 1 mg/kg and planned 0.25 mg/kg dose escalations every 3 months. Over 7 months of treatment he showed marked reduction in pain, bone turnover markers (BTMs), and tumor growth rate. Denosumab did not appear to impair healing of a femoral fracture that occurred while on treatment. With initiation of treatment he developed hypophosphatemia and secondary hyperparathyroidism, necessitating supplementation with phosphorus, calcium, and calcitriol. BTMs showed rapid and sustained suppression. With discontinuation there was rapid and dramatic rebound of BTMs with cross-linked C-telopeptide (reflecting osteoclast activity) exceeding pretreatment levels, accompanied by severe hypercalcemia. In this child, denosumab lead to dramatic reduction of FD expansion and FD-related bone pain. Denosumab was associated with clinically significant disturbances of mineral metabolism both while on treatment and after discontinuation. Denosumab treatment of FD warrants further study to confirm efficacy and determine potential morbidity, as well as to determine the mechanism of RANKL in the pathogenesis of FD and related bone marrow stromal cell diseases.