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1.
Bioorg Med Chem Lett ; 91: 129362, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37295614

RESUMO

Inhibition of monoacylglycerol transferase 2 (MGAT2) has recently emerged as a potential therapeutic strategy for the treatment of metabolic diseases such as obesity, diabetes and non-alcoholic steatohepatitis (NASH). Metabolism studies with our clinical lead (1) suggested variability in in vitro glucuronidation rates in liver microsomes across species, which made projection of human doses challenging. In addition, the observation of deconjugation of the C3-C4 double bond in the dihydropyridinone ring of 1 in solution had the potential to complicate its clinical development. This report describes our lead optimization efforts in a novel pyridinone series, exemplified by compound 33, which successfully addressed both of these potential issues.


Assuntos
Doenças Metabólicas , Monoglicerídeos , Humanos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Inibidores Enzimáticos/química , Obesidade/tratamento farmacológico , Doenças Metabólicas/tratamento farmacológico
2.
Bioorg Med Chem ; 85: 117273, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37030194

RESUMO

GPR40 AgoPAMs are highly effective antidiabetic agents that have a dual mechanism of action, stimulating both glucose-dependent insulin and GLP-1 secretion. The early lipophilic, aromatic pyrrolidine and dihydropyrazole GPR40 AgoPAMs from our laboratory were highly efficacious in lowering plasma glucose levels in rodents but possessed off-target activities and triggered rebound hyperglycemia in rats at high doses. A focus on increasing molecular complexity through saturation and chirality in combination with reducing polarity for the pyrrolidine AgoPAM chemotype resulted in the discovery of compound 46, which shows significantly reduced off-target activities as well as improved aqueous solubility, rapid absorption, and linear PK. In vivo, compound 46 significantly lowers plasma glucose levels in rats during an oral glucose challenge yet does not demonstrate the reactive hyperglycemia effect at high doses that was observed with earlier GPR40 AgoPAMs.


Assuntos
Glicemia , Hiperglicemia , Ratos , Animais , Receptores Acoplados a Proteínas G , Peptídeo 1 Semelhante ao Glucagon , Hipoglicemiantes/farmacologia , Pirrolidinas/farmacologia , Pirrolidinas/química , Insulina
3.
Pharm Res ; 38(5): 901-914, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33880721

RESUMO

PURPOSE: The use of two solvent-casted film methods to select optimal polymer compositions for amorphous solid dispersions prepared to support preclinical pharmacokinetic and toxicology studies is described. METHODS: Evaporation of solvent from cover slips by using nitrogen flow, and solvent removal from vials by using rotary evaporation were employed. The films prepared on cover slips were evaluated under the microscope to determine crystallinity. The methods were validated by scaling up corresponding SDDs, evaluating SDD's dissolution, and comparing those results to the dissolution of drug-polymer films. Subsequently, SDD suspensions were prepared and dosed orally to rats to determine pharmacokinetic parameters. This was done by using three compounds from our pipeline and evaluating multiple polymers. RESULTS: The dissolution of generated films showed good agreement with the dissolution of spray dried dispersions when the films were fully amorphous (Compound A and B). In contrast, there was disagreement between film and SDD dissolution when the films had crystallized (Compound C). The in vivo exposure results indicated that the polymer choice based on the film screening methods would have been accurate for drug-polymer films that were amorphous (Compound A and B). Two additional case studies (Compound D and E) are presented, showing good agreement between in vivo and in vitro results. CONCLUSION: This study established the ability of two film casting screening methods to predict the in vitro and in vivo performance of corresponding SDDs, provided that the films are fully amorphous.


Assuntos
Composição de Medicamentos/métodos , Polímeros/química , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Liberação Controlada de Fármacos , Ratos , Solubilidade , Solventes/química , Testes de Toxicidade/métodos , Difração de Raios X
4.
Molecules ; 26(7)2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807401

RESUMO

The aim of this work is to present an approach to enhance the dissolution of progestin medication, megestrol acetate (also known as MEGACE), for improving the dissolution rate and kinetic solubility by incorporating nano graphene oxide (nGO). An antisolvent precipitation process was investigated for nGO-drug composite preparation, where prepared composites showed crystalline properties that were similar to the pure drug but enhanced aqueous dispersibility and colloidal stability. To validate the efficient release profile of composite, in vitro dissolution testing was carried out using United States Pharmacopeia, USP-42 paddle method, with gastric pH (1.4) and intestinal pH (6.5) solutions to mimic in vivo conditions. Pure MA is practically insoluble (2 µg/mL at 37 °C). With the incorporation of nGO, it was possible to dissolve nearly 100% in the assay. With the incorporation of 1.0% of nGO, the time required to dissolve 50% and 80% of drug, namely T50 and T80, decreased from 138.0 min to 27.0 min, and the drug did not dissolve for 97.0 min in gastric media, respectively. Additionally, studies done in intestinal media have revealed T50 did not dissolve for 92.0 min. This work shows promise in incorporating functionalized nanoparticles into the crystal lattice of poorly soluble drugs to improve dissolution rate.


Assuntos
Excipientes/química , Grafite/química , Acetato de Megestrol , Nanopartículas/química , Disponibilidade Biológica , Química Farmacêutica , Composição de Medicamentos , Interações Hidrofóbicas e Hidrofílicas , Acetato de Megestrol/química , Acetato de Megestrol/farmacocinética , Solubilidade
5.
Blood ; 131(1): 108-120, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29051183

RESUMO

Leukemia relapse remains the major cause of allogeneic hematopoietic stem cell transplantation (HCT) failure, and the prognosis for patients with post-HCT relapse is poor. There is compelling evidence that potent selective antileukemic effects can be delivered by donor T cells specific for particular minor histocompatibility (H) antigens. Thus, T-cell receptors (TCRs) isolated from minor H antigen-specific T cells represent an untapped resource for developing targeted T-cell immunotherapy to manage post-HCT leukemic relapse. Recognizing that several elements may be crucial to the efficacy and safety of engineered T-cell immunotherapy, we developed a therapeutic transgene with 4 components: (1) a TCR specific for the hematopoietic-restricted, leukemia-associated minor H antigen, HA-1; (2) a CD8 coreceptor to promote function of the class I-restricted TCR in CD4+ T cells; (3) an inducible caspase 9 safety switch to enable elimination of the HA-1 TCR T cells in case of toxicity; and (4) a CD34-CD20 epitope to facilitate selection of the engineered cell product and tracking of transferred HA-1 TCR T cells. The T-cell product includes HA-1 TCR CD4+ T cells to augment the persistence and function of the HA-1 TCR CD8+ T cells and includes only memory T cells; naive T cells are excluded to limit the potential for alloreactivity mediated by native TCR coexpressed by HA-1 TCR T cells. We describe the development of this unique immunotherapy and demonstrate functional responses to primary leukemia by CD4+ and CD8+ T cells transduced with a lentiviral vector incorporating the HA-1 TCR transgene construct.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Imunoterapia , Leucemia/terapia , Linfócitos T/imunologia , Células Cultivadas , Humanos , Leucemia/imunologia , Antígenos de Histocompatibilidade Menor/metabolismo , Oligopeptídeos/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo
6.
Biomed Microdevices ; 22(3): 52, 2020 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-32770358

RESUMO

Although microfluidic micro-electromechanical systems (MEMS) are well suited to investigate the effects of mechanical force on large populations of cells, their high-throughput capabilities cannot be fully leveraged without optimizing the experimental conditions of the fluid and particles flowing through them. Parameters such as flow velocity and particle size are known to affect the trajectories of particles in microfluidic systems and have been studied extensively, but the effects of temperature and buffer viscosity are not as well understood. In this paper, we explored the effects of these parameters on the timing of our own cell-impact device, the µHammer, by first tracking the velocity of polystyrene beads through the device and then visualizing the impact of these beads. Through these assays, we find that the timing of our device is sensitive to changes in the ratio of inertial forces to viscous forces that particles experience while traveling through the device. This sensitivity provides a set of parameters that can serve as a robust framework for optimizing device performance under various experimental conditions, without requiring extensive geometric redesigns. Using these tools, we were able to achieve an effective throughput over 360 beads/s with our device, demonstrating the potential of this framework to improve the consistency of microfluidic systems that rely on precise particle trajectories and timing.


Assuntos
Dispositivos Lab-On-A-Chip , Sistemas Microeletromecânicos/instrumentação , Soluções Tampão , Desenho de Equipamento , Microesferas , Tamanho da Partícula , Poliestirenos/química , Temperatura , Viscosidade
7.
J Fish Biol ; 96(1): 194-201, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31729024

RESUMO

We explored the macroevolutionary dynamics of miniaturisation in New World anchovies by integrating a time-calibrated phylogeny, geometric morphometrics and phylogenetic comparative methods. We found that the paedomorphic species Amazonsprattus scintilla occupies a novel region of shape space, while the dwarf species Anchoviella manamensis has an overall shape consistent with other anchovies. We found that miniaturisation did not increase overall clade disparity in size or shape beyond the expectations of Brownian motion, nor were there differences in rates of size or shape evolution among clades. Overall, our study shows that while the mode of miniaturisation influences shape evolution, the phenotypic novelty produced by the evolution of miniaturisation did not seem to alter macroevolutionary dynamics.


Assuntos
Peixes/anatomia & histologia , Miniaturização , Animais , Evolução Biológica , Tamanho Corporal/genética , Peixes/classificação , Peixes/genética , Filogenia
8.
J Pediatr Hematol Oncol ; 41(1): e34-e37, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29432310

RESUMO

Congenital brain tumors are rare, representing <2% of all childhood brain tumors. Of these, ependymoblastoma is a profoundly aggressive embryonal brain tumor that is included in the diagnostic entity known as an embryonal tumor with multilayered rosettes. This report of a congenital ependymoblastoma diagnosed at birth aims to highlight how much remains unknown about embryonal tumor with multilayered rosettes and the devastating prognosis of this condition. Despite recent advancements made in identifying molecular targets for therapy, this tumor continues to have a high rate of recurrence with few successful treatment options, especially when diagnosed in the newborn period.


Assuntos
Neoplasias Encefálicas/congênito , Neoplasias Encefálicas/diagnóstico por imagem , Tumores Neuroectodérmicos Primitivos/congênito , Tumores Neuroectodérmicos Primitivos/diagnóstico por imagem , Adulto , Neoplasias Encefálicas/patologia , Feminino , Humanos , Recém-Nascido , Tumores Neuroectodérmicos Primitivos/patologia , Gravidez
9.
BMC Evol Biol ; 18(1): 116, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-30021522

RESUMO

BACKGROUND: One of the most perplexing questions in evolutionary biology is why some lineages diversify into many species, and others do not. In many cases, ecological opportunity has played an important role, leading to diversification along trophic or habitat-based axes. The Goodeidae (Teleostomi: Cyprinodontiformes) are a family of freshwater fishes with two subfamilies: Goodeinae (42 species, viviparous, heterogeneous habitats, Mesa Central of Mexico) and Empetrichthyinae (4 species, oviparous, homogeneous habitats, Great Basin of the United States). These discrepant sets of characteristics and their sister-group relationship make the goodeids amenable to a comparative study of diversification. We gathered lateral body images from more than 1600 specimens of all extant species in the family. Geometric morphometric, and phylogenetic comparative analyses were used to address whether higher species diversity correlates with higher rates of morphological shape evolution and whether there are differences in functional/habitat modules between the two subfamilies. RESULTS: This study recovered a higher rate of overall body shape evolution in the Goodeinae that is nearly double in magnitude compared to the Empetrichthyinae. A modularity test indicated that the Goodeinae displayed elevated rates of morphological evolution in comparison to the Empetrichthyinae when only trunk (locomotor) regions were compared between subfamilies. No significant differences in evolutionary shape rates were recovered when the trophic (head) regions were compared between subfamilies. DISCUSSION: These results support the hypothesis that Mexican goodeids radiated via an ecological opportunity scenario into a wide-array of novel habitats in the island-like Mesa Central as evidenced by their high rate of shape evolution, relative to the Empetrichthyinae. This study quantitatively unraveled the drivers of evolution and eliminated trophic specialization as a driving force within the Goodeidae. CONCLUSIONS: A combination of phylogenetic and morphometric data, and phylogenetic comparative analyses were used to examine body shape rate evolution within the Goodeidae. Results support the hypothesis that species in the subfamily Goodeinae on the central Mexican plateau had a higher rate of body shape evolution relative to its sister subfamily Empetrichthyinae in the Great Basin suggesting that the Goodeinae diversified via an ecological opportunity scenario along habitat, rather than trophic axes.


Assuntos
Biodiversidade , Ciprinodontiformes/classificação , Espécies em Perigo de Extinção , Água Doce , Animais , Calibragem , Ciprinodontiformes/anatomia & histologia , Geografia , México , Filogenia , Especificidade da Espécie , Fatores de Tempo
10.
Pediatr Dermatol ; 35(6): e389-e390, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30178566

RESUMO

Melanotic neuroectodermal tumors of infancy are rare tumors arising from the neural crest and typically present during the first 12 months of life. The majority involve the facial bones, although melanotic neuroectodermal tumors of infancy of the skull and extremities have been observed with less frequency, as in the present case. This entity may initially be presented to the dermatologist as a scalp mass and should be considered in the differential diagnosis of infants with rapidly growing head and neck lesions.


Assuntos
Tumor Neuroectodérmico Melanótico/diagnóstico , Neoplasias Cranianas/diagnóstico , Diagnóstico Diferencial , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Tumor Neuroectodérmico Melanótico/cirurgia , Crânio/patologia , Neoplasias Cranianas/patologia
11.
Pediatr Neurosurg ; 53(2): 100-107, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29316543

RESUMO

INTRODUCTION: Myelomeningocele (MMC) is an open neural tube defect routinely surgically closed within 48 h of birth to prevent secondary infection. Up to 18% of patients experience wound complications, and 85% require shunting for hydrocephalus. We hypothesized that wound complications could be reduced by cerebrospinal fluid (CSF) diversion at the time of closure. METHODS: Institutional review board approval was obtained to review records of the 88 patients who underwent MMC closure between January 2005 and June 2016 at the Children's Hospital of Pittsburgh. Twenty-three patients (26%) had an external ventricular drain (EVD) placed at the time of MMC closure and underwent 7-11 days of CSF drainage. Fourteen patients (16%) had a shunt placed at the time of MMC closure, and 51 (58%) had no form of CSF diversion at the time of MMC closure. RESULTS: Patients with an EVD or shunt placed at the time of closure had no wound complications. In contrast, 8 patients (16%) without CSF diversion at closure developed wound complications (p = 0.048). Seven of the 8 wound complications occurred in the 71 patients with evidence of hydrocephalus at birth (p = 0.98). Of patients with evidence of hydrocephalus at the time of MMC closure, wound complications had a higher rate of occurrence among patients who did not receive a shunt or EVD at closure (p = 0.01). When comparing only patients with evidence of hydrocephalus at birth, the EVD group alone had a lower rate of wound complications than patients who did not receive CSF diversion at the time of closure (p = 0.031). CONCLUSIONS: These results suggest that addressing hydrocephalus at the time of MMC closure significantly reduces the likelihood of wound complications and may justify temporary CSF diversion at birth, at least in those patients manifesting hydrocephalus.


Assuntos
Drenagem , Hidrocefalia/cirurgia , Meningomielocele/complicações , Derivação Ventriculoperitoneal/métodos , Feminino , Humanos , Hidrocefalia/complicações , Recém-Nascido , Masculino , Meningomielocele/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Estudos Retrospectivos
12.
Pediatr Neurosurg ; 52(1): 36-40, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27595482

RESUMO

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare lesion that typically manifests in the first year of life, most commonly involving the facial bones. We present 2 infants with MNTI involving the posterior skull with associated compression of the superior sagittal sinus (SSS). A review of the anatomical locations of MNTI is offered, and the implications of SSS involvement are described. This represents the first known description of MNTI with involvement of the posterior SSS.


Assuntos
Tumor Neuroectodérmico Melanótico/diagnóstico por imagem , Tumor Neuroectodérmico Melanótico/cirurgia , Seio Sagital Superior/diagnóstico por imagem , Seio Sagital Superior/cirurgia , Feminino , Humanos , Lactente , Masculino
13.
Am J Obstet Gynecol ; 214(2): 277.e1-277.e7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26363481

RESUMO

BACKGROUND: Twin pregnancies are associated with an increased risk of perinatal morbidity and mortality primarily due to spontaneous preterm deliveries. The mean gestational age for delivery is 35.3 weeks and twins account for 23% of preterm births <32 weeks. A number of strategies have been proposed to prevent preterm deliveries: tocolytics, bed rest, hospitalization, home uterine activity monitoring, cerclage, and most recently, progesterone. Unfortunately, none have proven effective. Recent metaanalyses and reviews suggest that transvaginal cervical length (TVCL) ultrasound in the second trimester is a powerful predictor of preterm birth among asymptomatic women. Indeed, TVCL has the highest positive and negative predictive values for determining the risk of spontaneous preterm delivery in twin pregnancies. It follows that TVCL assessment may allow identification of a subset of twin pregnancies that re better candidates for interventions intended to prevent prematurity. OBJECTIVE: We sought to determine whether use of TVCL prolongs gestation in twin pregnancies. STUDY DESIGN: This is a multicenter, randomized, controlled trial of 125 dichorionic or monochorionic/diamniotic twin pregnancies without prior preterm birth <28 weeks. The study group (n = 63) had TVCL and digital exams monthly from 16-28 weeks and were managed with a standard algorithm for activity restriction and cerclage. The control group (n = 62) had monthly digital cervical examinations but no routine TVCL ultrasound examinations. The primary outcome was gestational age at delivery. Secondary outcomes included percentage of deliveries <35 weeks, and maternal and neonatal outcomes. RESULTS: The mean gestational age at delivery was 35.7 weeks (95% confidence interval [CI], 35.2-36.2) among those managed with TVCL and 35.5 weeks (95% CI, 34.7-36.4) among the control patients. The Kaplan-Meier estimates of deliveries <38 weeks were not significantly different between groups. This was true whether we compared curves with a log-rank test (P = .67), Breslow test (P = .67), or Tarone-Ware test (P = .64). The percentage of deliveries <35 0/7 weeks did not differ: 27.4% for subjects managed with routine TVCL and 28.6% for control subjects (relative risk, 0.96; 95% CI, 0.60-1.54). Our study had an 80% power to detect a 12-day difference in the gestational age at delivery with 95% confidence. CONCLUSION: The overall mean length of gestation and the percentage of women delivering <35 weeks did not differ between twin gestations managed with TVCL and digital exams monthly from 16-28 weeks with a standard algorithm for activity restriction and cerclage and controls who had monthly digital cervical examinations but no routine TVCL. Routine second-trimester transvaginal ultrasound assessment of cervical length is not associated with improved outcomes when incorporated into the standard management of otherwise low-risk twin pregnancies.


Assuntos
Repouso em Cama/métodos , Cerclagem Cervical/métodos , Colo do Útero/diagnóstico por imagem , Gravidez de Gêmeos , Nascimento Prematuro/prevenção & controle , Adulto , Medida do Comprimento Cervical , Parto Obstétrico , Feminino , Humanos , Estimativa de Kaplan-Meier , Gravidez , Medição de Risco , Adulto Jovem
14.
Childs Nerv Syst ; 32(8): 1463-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27125518

RESUMO

INTRODUCTION: PHACE syndrome is a neurocutaneous disorder involving large facial hemangiomas in association with posterior fossa abnormalities, cerebral arterial anomalies, cardiac defects, and eye abnormalities. A recent consensus statement has delineated criteria necessary for the diagnosis of PHACE syndrome. Extracutaneous manifestations of PHACE syndrome predominately affect the cerebrovascular system. To date, there are no reports of cerebral cavernous malformations (CCMs) in children with PHACE syndrome. METHODS: We reviewed the charts of children admitted to the Children''s Hospital of Pittsburgh who met criteria for PHACE syndrome, and evaluated neuroimaging for cerebrovascular abnormalities, including the finding of CCMs. RESULTS: Six children met criteria for PHACE syndrome at our institution over a 10-year period. All children were female. All children had cerebrovascular abnormalities sufficient to meet major criteria for diagnosis. Four children (66.7 %) were found incidentally to have CCMs; all lesions measured less than 5 mm at the time of diagnosis and were asymptomatic. CONCLUSION: At present, CCMs are not listed among the diagnostic criteria for PHACE syndrome, and they have not previously been reported in association with PHACE syndrome. Hypoxic injury in utero may be the common denominator in the pathogenesis of many of the abnormalities already accepted in the criteria for PHACE syndrome and the formation of CCMs. In the setting of PHACE syndrome, we encourage clinicians to evaluate children for CCMs, which are readily apparent on the already-recommended screening MRIs.


Assuntos
Coartação Aórtica/complicações , Anormalidades do Olho/complicações , Malformações Arteriovenosas Intracranianas/complicações , Síndromes Neurocutâneas/complicações , Coartação Aórtica/diagnóstico por imagem , Pré-Escolar , Anormalidades do Olho/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Lactente , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino , Síndromes Neurocutâneas/diagnóstico por imagem
15.
Pediatr Blood Cancer ; 62(2): 240-245, 2015 02.
Artigo em Inglês | MEDLINE | ID: mdl-25382690

RESUMO

BACKGROUND: Radiation therapy (RT)-induced effects in children treated for low grade glioma (LGG) can result in worsening of neurologic symptoms and clinical and radiographic deterioration. Treatment for radiation-induced tumor enlargement is based on symptom control and usually involves steroids. PROCEDURE: We conducted a retrospective review of children with LGG treated with RT who developed symptomatic radiation-induced tumor enlargement and were managed with bevacizumab. Charts were abstracted for onset and duration of RT changes, toxicity and doses of dexamethasone and bevacizumab. Tumor volumes prior to RT, at maximal size following RT, after bevacizumab administration, and at follow-up were evaluated. RESULTS: Five children were treated with bevacizumab for symptomatic radiation-induced tumor enlargement following RT for LGG at a median of 4.2 months (range, 1-11 months) after completion of RT. The median increase in volume of tumor was 195.4% (range, 115.5-309%) compared to the pre-RT volume. Bevacizumab 5-10 mg/kg was administered IV q 2-4 weeks as primary treatment (n = 1) or to assist in weaning patients off steroids (n = 4). All children on high dose steroids (n = 4) were weaned off or to physiologic doses of hydrocortisone. Two children developed avascular necrosis after prolonged steroid use and while on bevacizumab. Radiographically, all children showed significant improvement and are now a median of 31 months (range, 18-50 months) from the completion of radiation without requiring additional tumor-related therapy. CONCLUSIONS: Bevacizumab can play an important role in children with symptomatic radiation changes following LGG treatment, allowing patients to avoid or minimize the toxicity of long-term steroid use. Pediatr Blood Cancer 2015;62:240-245. © 2014 Wiley Periodicals, Inc.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Neoplasias Induzidas por Radiação/tratamento farmacológico , Lesões por Radiação/tratamento farmacológico , Adolescente , Antineoplásicos Hormonais/uso terapêutico , Criança , Pré-Escolar , Dexametasona/uso terapêutico , Feminino , Humanos , Masculino , Estudos Retrospectivos
16.
Childs Nerv Syst ; 31(1): 115-21, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25119153

RESUMO

PURPOSE: Neurocutaneous melanosis (NCM) is a rare congenital disorder occurring in children born with multiple or large congenital melanocytic nevi (CMN) in association with melanocytic deposits in the leptomeninges. Multiple associations between NCM and other syndromes or neurologic abnormalities have been reported. Of note, there exists a possible association between NCM and tethered cord (TC). METHODS: We retrospectively reviewed charts and films of all patients with the diagnosis of NCM at the Children's Hospital of Pittsburgh (CHP) from August 2002 to present. RESULTS: Five children met the criteria for NCM at our institution over a 12-year period. Apart from the melanocytic deposits, one or more additional spinal abnormalities were identified in all children. Three children had radiographic evidence of a low-lying conus medullaris, two of which also demonstrated lipomatous infiltration of the filum terminale, consistent with a tethered cord (TC). CONCLUSIONS: Clinical features of NCM include dermatologic and neurologic manifestations. To date, this is the first series to note an association between NCM and TC. While nearly all recent series of NCM patients advocate early MRI of the neuroaxis, we recommend screening imaging of the spine on children with possible NCM regardless of the locations of CMN.


Assuntos
Melanose/complicações , Defeitos do Tubo Neural/complicações , Síndromes Neurocutâneas/complicações , Adolescente , Encéfalo/patologia , Criança , Pré-Escolar , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Melanose/diagnóstico , Síndromes Neurocutâneas/diagnóstico , Exame Neurológico , Medula Espinal/patologia
17.
J Pharmacol Exp Ther ; 350(1): 22-35, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24741074

RESUMO

Identification of therapeutic strategies that might enhance the efficacy of B-cell lymphoma-2 (Bcl-2) inhibitor ABT-737 [N-{4-[4-(4-chloro-biphenyl-2-ylmethyl)-piperazin-1-yl]-benzoyl}-4-(3-dimethylamino-1-phenylsulfanylmethyl-propylamino)-3-nitro-benzenesulfonamide] is of great interest in many cancers, including glioma. Our recent study suggested that Akt is a crucial mediator of apoptosis sensitivity in response to ABT-737 in glioma cell lines. Inhibitors of phosphatidylinositol 3-kinase (PI3K)/Akt are currently being assessed clinically in patients with glioma. Because PI3K/Akt inhibition would be expected to have many proapoptotic effects, we hypothesized that there may be unique synergy between PI3K inhibitors and Bcl-2 homology 3 mimetics. Toward this end, we assessed the combination of the PI3K/Akt inhibitor NVP-BKM120 [5-(2,6-dimorpholinopyrimidin-4-yl)-4-(trifluoromethyl)pyridin-2-amine] and the Bcl-2 family inhibitor ABT-737 in established and primary cultured glioma cells. We found that the combined treatment with these agents led to a significant activation of caspase-8 and -3, PARP, and cell death, irrespective of PTEN status. The enhanced lethality observed with this combination also appears dependent on the loss of mitochondrial membrane potential and release of cytochrome c, smac/DIABLO, and apoptosis-inducing factor to the cytosol. Further study revealed that the upregulation of Noxa, truncation of Bid, and activation of Bax and Bak caused by these inhibitors were the key factors for the synergy. In addition, we demonstrated the release of proapoptotic proteins Bim and Bak from Mcl-1. We found defects in chromosome segregation leading to multinuclear cells and loss of colony-forming ability, suggesting the potential use of NVP-BKM120 as a promising agent to improve the anticancer activities of ABT-737.


Assuntos
Aminopiridinas/farmacologia , Antineoplásicos/farmacologia , Compostos de Bifenilo/toxicidade , Caspases/metabolismo , Dano ao DNA/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Morfolinas/farmacologia , Nitrofenóis/toxicidade , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Sulfonamidas/toxicidade , Fator de Indução de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose , Proteína 11 Semelhante a Bcl-2 , Caspase 3/metabolismo , Caspase 8/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Segregação de Cromossomos/efeitos dos fármacos , Citocromos c/metabolismo , Sinergismo Farmacológico , Glioblastoma/enzimologia , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas Mitocondriais/metabolismo , Piperazinas/toxicidade , Poli(ADP-Ribose) Polimerases/metabolismo , Cultura Primária de Células , Proteínas Proto-Oncogênicas , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
18.
J Neurooncol ; 120(3): 459-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25139025

RESUMO

We previously observed that glioma cells are differentially sensitive to ABT-737 and, when used as a single-agent, this drug failed to induce apoptosis. Identification of therapeutic strategies to enhance the efficacy of the Bcl-2 inhibitor ABT-737 in human glioma is of interest. Histone deacetylation inhibitors (HDACI) are currently being assessed clinically in patients with glioma, as regulation of epigenetic abnormalities is expected to produce pro-apoptotic effects. We hypothesized that co-treatment of glioma with a BH3-mimetic and HDACI may induce cellular death. We assessed the combination of ABT-737 and HDACI SAHA in established and primary cultured glioma cells. We found combination treatment led to significant cellular death when compared to either drug as single agent and demonstrated activation of the caspase cascade. This enhanced apoptosis also appears dependent upon the loss of mitochondrial membrane potential and the release of cytochrome c and AIF into the cytosol. The upregulation of Noxa, truncation of Bid, and activation of Bax caused by this combination were important factors for cell death and the increased levels of Noxa functioned to sequester Mcl-1. This combination was less effective in PTEN-deficient glioma cells. Both genetic and pharmacologic inactivation of the PI3K/Akt signaling pathway sensitized PTEN-deleted glioma cells to the combination. This study demonstrates that antagonizing apoptosis-resistance pathways, such as targeting the Bcl-2 family in combination with epigenetic modifiers, may induce cell death. These findings extend our previous observations that targeting the PI3K/Akt pathway may be additionally necessary to promote apoptosis in cancers lacking PTEN functionality.


Assuntos
Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Glioma/tratamento farmacológico , Inibidores de Histona Desacetilases/farmacologia , Nitrofenóis/farmacologia , Sulfonamidas/farmacologia , Apoptose/efeitos dos fármacos , Fator de Indução de Apoptose/metabolismo , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Quimioterapia Combinada , Glioma/genética , Glioma/patologia , Glioma/fisiopatologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , PTEN Fosfo-Hidrolase/deficiência , PTEN Fosfo-Hidrolase/genética , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo
19.
Pediatr Blood Cancer ; 61(8): 1490-2, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24501091

RESUMO

The development of Moyamoya syndrome (MMS) after cranial irradiation for pediatric tumors has been well established. However, information on the development of MMS after proton beam radiotherapy is sparse. We present the case of a 2-year-old child who developed radiation-induced MMS after treatment with proton beam therapy.


Assuntos
Neoplasias do Tronco Encefálico/radioterapia , Ependimoma/radioterapia , Doença de Moyamoya/etiologia , Terapia com Prótons/efeitos adversos , Pré-Escolar , Humanos , Masculino , Terapia com Prótons/métodos
20.
J Pharm Sci ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608727

RESUMO

The preparation of amorphous solid dispersions (ASDs) represents a promising strategy for addressing the solubility limitations of poorly soluble drugs, facilitating enhanced oral absorption. Acidic polymers such as cellulose acetate phthalate (CAP) and hydroxypropyl methylcellulose phthalate (HPMCP) have emerged as effective carriers for ASDs. Although the hydrolytic degradation of these polymers has been documented, its impact on the stability of ASDs has not been systematically investigated. This research aimed to explore the potential hydrolysis of CAP and HPMCP and how it influences the stability of ASDs containing ketoconazole (KTZ), at drug loadings of 10 % and 50 %. Our study utilized thermal analysis, infrared spectroscopy, and evaluations of physical and chemical stability. The results revealed that although KTZ remained physically stable in all ASDs over 60 days under various stability conditions, the emergence of crystalline phthalic acid (PA), a byproduct of polymer hydrolysis, was observed at elevated temperatures and relative humidity levels. The acidic microenvironment fostered by the release of PA further catalyzed drug chemical degradation. This study underscores the susceptibility of CAP and HPMCP to hydrolytic degradation, highlighting the inherent risk of PA-induced drug degradation, particularly for acid-labile compounds. These insights into the understanding of polymer hydrolysis in ASDs pave the way for the development of targeted approaches to safeguard drug stability and optimize pharmaceutical formulations for enhanced bioavailability, efficacy, and safety.

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