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1.
Childs Nerv Syst ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819669

RESUMO

Teratomas account for 18-20% of all intracranial germ cell tumors and mostly occur in the pineal region with only a few cases of pediatric sellar and suprasellar teratomas described in the literature. Here, we present a case of a child with an intracranial mature teratoma with pancreatic features causing vasospasm and subsequent stroke, found to be positive for CDKN2A-an independent variant associated with malignancy and small vessel disease leading to stroke.

2.
Pediatr Dev Pathol ; 27(1): 13-22, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37801635

RESUMO

Liver histology in infants with cystic fibrosis (CF) and persistent cholestasis is seldom reported in detail. We extend previous observation of a distinctive intrahepatic cholangiopathy (ICCF) to 3 additional infants homozygous for CFTR pathological variants and a fourth infant with a heterozygous CFTR variant, summarizing our experience in 10 infants with CFTR variants and persistent cholestasis. Cholangiograms demonstrate abnormal extrahepatic ducts in 2 infants with CF, 1 with uniform dilatation interpreted as a choledochal cyst and the other with narrow patent ducts. Liver histology in 3 CF homozygotes had prominent ductular reaction with a focally destructive cholangiolitis (inflammation of small bile ducts). The CFTR heterozygote had generalized portal edema with ductular reaction and paucity but no cholangitis. Cholestasis slowly subsided in all infants. ICCF is characterized by severe ductular reaction, prominent cholangiocyte injury, and multifocal necrotizing cholangiolitis. Local aggregates of portal ceroid might suggest previous bile leakage from damaged ducts. ICCF in liver biopsies from infants with cystic fibrosis and persistent cholestasis is unrelated to the specific CFTR genotype. Liver biopsy findings and intraoperative cholangiogram help rule out biliary atresia. ICCF is an early manifestation of CF, a likely prototype for pathogenesis of cystic fibrosis liver disease later in life.


Assuntos
Atresia Biliar , Colestase Intra-Hepática , Colestase , Fibrose Cística , Hepatite , Lactente , Humanos , Fibrose Cística/complicações , Fibrose Cística/genética , Fibrose Cística/patologia , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Colestase/diagnóstico , Colestase/etiologia , Fígado/patologia , Atresia Biliar/patologia , Hepatite/patologia , Colestase Intra-Hepática/patologia
3.
Acta Neuropathol Commun ; 11(1): 203, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38115140

RESUMO

The prognosis of childhood medulloblastoma (MB) is often poor, and it usually requires aggressive therapy that adversely affects quality of life. microRNA-211 (miR-211) was previously identified as an important regulator of cells that descend from neural cells. Since medulloblastomas primarily affect cells with similar ontogeny, we investigated the role and mechanism of miR-211 in MB. Here we showed that miR-211 expression was highly downregulated in cell lines, PDXs, and clinical samples of different MB subgroups (SHH, Group 3, and Group 4) compared to normal cerebellum. miR-211 gene was ectopically expressed in transgenic cells from MB subgroups, and they were subjected to molecular and phenotypic investigations. Monoclonal cells stably expressing miR-211 were injected into the mouse cerebellum. miR-211 forced expression acts as a tumor suppressor in MB both in vitro and in vivo, attenuating growth, promoting apoptosis, and inhibiting invasion. In support of emerging regulatory roles of metabolism in various forms of cancer, we identified the acyl-CoA synthetase long-chain family member (ACSL4) as a direct miR-211 target. Furthermore, lipid nanoparticle-coated, dendrimer-coated, and cerium oxide-coated miR-211 nanoparticles were applied to deliver synthetic miR-211 into MB cell lines and cellular responses were assayed. Synthesizing nanoparticle-miR-211 conjugates can suppress MB cell viability and invasion in vitro. Our findings reveal miR-211 as a tumor suppressor and a potential therapeutic agent in MB. This proof-of-concept paves the way for further pre-clinical and clinical development.


Assuntos
Neoplasias Cerebelares , Meduloblastoma , MicroRNAs , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Cerebelares/metabolismo , Regulação Neoplásica da Expressão Gênica , Homeostase , Ligases/genética , Ligases/metabolismo , Meduloblastoma/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Qualidade de Vida
4.
J Neurosurg Pediatr ; 32(3): 351-357, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37327147

RESUMO

OBJECTIVE: Tuberous sclerosis is a rare genetic condition caused by TSC1 or TSC2 mutations that can be inherited, sporadic, or the result of somatic mosaicism. Subependymal giant-cell astrocytoma (SEGA) is a major diagnostic feature of tuberous sclerosis complex (TSC). This study aimed to present a series of cases in which a pathological diagnosis of SEGA was not diagnostic of tuberous sclerosis. METHODS: The authors retrospectively reviewed a clinical case series of 5 children who presented with a SEGA tumor to Johns Hopkins All Children's Hospital and St. Louis Children's Hospital between 2010 and 2022 and whose initial genetic workup was negative for tuberous sclerosis. All patients were treated with craniotomy for SEGA resection. TSC genetic testing was performed on all SEGA specimens. RESULTS: The children underwent open frontal craniotomy for SEGA resection from the ages of 10 months to 14 years. All cases demonstrated the classic imaging features of SEGA. Four were centered at the foramen of Monro and 1 in the occipital horn. One patient presented with hydrocephalus, 1 with headaches, 1 with hand weakness, 1 with seizures, and 1 with tumor hemorrhage. Somatic TSC1 mutation was present in the SEGA tumors of 2 patients and TSC2 mutation in 1 patient. Germline TSC mutation testing was negative for all 5 cases. No patient had other systemic findings of tuberous sclerosis on ophthalmological, dermatological, neurological, renal, or cardiopulmonary assessments and thus did not meet the clinical criteria for tuberous sclerosis. The average follow-up was 6.7 years. Recurrence was noted in 2 cases, in which 1 patient underwent radiosurgery and 1 was started on a mammalian target of rapamycin (mTOR) inhibitor (rapamycin). CONCLUSIONS: There may be intracranial implications of somatic mosaicism associated with tuberous sclerosis. Children who are diagnosed with SEGA do not necessarily have a diagnosis of tuberous sclerosis. Tumors may carry a TSC1 or TSC2 mutation, but germline testing can be negative. These children should continue to be followed with serial cranial imaging for tumor progression, but they may not require the same long-term monitoring as patients who are diagnosed with germline TSC1 or TSC2 mutations.

5.
Arthrosc Tech ; 12(3): e433-e440, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37013021

RESUMO

The purpose of this article is to describe a technique to restore both vertical and horizontal stability using an augmentation of the acromioclavicular ligament complex (ACLC) and coracoclavicular (CC) ligaments with the combination of synthetic and biological support. Our technique introduces a modification in the surgical procedure for acromioclavicular (AC) joint dislocations; it provides the use of biological supplements not only during the repair of the CC ligaments but also when the ACLC is restored due to the use of a dermal patch as an augmentation allograft after the use of a horizontal cerclage. The main purpose of this technique is to replicate the anatomy and functionality of the native ligaments that stabilize the AC joint to improve both clinical and functional results.

6.
Pediatr Transplant ; 27(2): e14443, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36419214

RESUMO

In pediatric patients who undergo heart transplantation, severe immune-mediated bowel disease has been reported. Management is complex, and there are little data discussing the use of basiliximab for immune-mediated bowel disease. This case report discusses a pediatric patient who developed immune-mediated bowel disease following heart transplantation and was successfully managed with basiliximab.


Assuntos
Transplante de Coração , Transplante de Rim , Criança , Humanos , Basiliximab/uso terapêutico , Imunossupressores/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico , Rejeição de Enxerto
7.
Case Rep Gastroenterol ; 15(3): 939-947, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34949979

RESUMO

Very early onset inflammatory bowel disease, autoimmune hepatitis (AIH), or primary sclerosing cholangitis (PSC) alone is a rare condition in young children. The combination of all 3 autoimmune disorders in a 16-month-old child is even rarer. The onset and etiology of these diseases is multifactorial and typically unknown. However, when the children are diagnosed, the accepted view point is that the inflammation was likely present for months to years prior. This case is unique because the gastrointestinal problems started from infancy, and evolved to the development of Crohn's disease, AIH, and PSC at a very early age. This case helps bring to light that very early onset autoimmune disorders may in fact present with symptoms of feeding difficulties, growth failure, and formula intolerance. Patients may be diagnosed initially with allergic enterocolitis in infancy. Although few children with these symptoms evolve to develop autoimmune diseases at an older age, clinicians should consider following these children more closely. This case also demonstrates how hard it is to diagnose very early onset autoimmune disorders, as they mimic other illnesses.

8.
Neuro Oncol ; 23(4): 572-585, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33844835

RESUMO

BACKGROUND: Medulloblastoma (MB) is an aggressive brain tumor that predominantly affects children. Recent high-throughput sequencing studies suggest that the noncoding RNA genome, in particular long noncoding RNAs (lncRNAs), contributes to MB subgrouping. Here we report the identification of a novel lncRNA, lnc-HLX-2-7, as a potential molecular marker and therapeutic target in Group 3 MBs. METHODS: Publicly available RNA sequencing (RNA-seq) data from 175 MB patients were interrogated to identify lncRNAs that differentiate between MB subgroups. After characterizing a subset of differentially expressed lncRNAs in vitro and in vivo, lnc-HLX-2-7 was deleted by CRISPR/Cas9 in the MB cell line. Intracranial injected tumors were further characterized by bulk and single-cell RNA-seq. RESULTS: Lnc-HLX-2-7 is highly upregulated in Group 3 MB cell lines, patient-derived xenografts, and primary MBs compared with other MB subgroups as assessed by quantitative real-time, RNA-seq, and RNA fluorescence in situ hybridization. Depletion of lnc-HLX-2-7 significantly reduced cell proliferation and 3D colony formation and induced apoptosis. Lnc-HLX-2-7-deleted cells injected into mouse cerebellums produced smaller tumors than those derived from parental cells. Pathway analysis revealed that lnc-HLX-2-7 modulated oxidative phosphorylation, mitochondrial dysfunction, and sirtuin signaling pathways. The MYC oncogene regulated lnc-HLX-2-7, and the small-molecule bromodomain and extraterminal domain family‒bromodomain 4 inhibitor Jun Qi 1 (JQ1) reduced lnc-HLX-2-7 expression. CONCLUSIONS: Lnc-HLX-2-7 is oncogenic in MB and represents a promising novel molecular marker and a potential therapeutic target in Group 3 MBs.


Assuntos
Neoplasias Cerebelares , Meduloblastoma , RNA Longo não Codificante , Carcinogênese , Neoplasias Cerebelares/genética , Proteínas de Homeodomínio , Humanos , Hibridização in Situ Fluorescente , Meduloblastoma/genética , RNA Longo não Codificante/genética , Fatores de Transcrição
10.
SAGE Open Med Case Rep ; 4: 2050313X16666232, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27621807

RESUMO

Management of patients with central nervous system tumors relies largely on magnetic resonance imaging scans to document disease progression or recurrence. The finding of new lesions always presents the challenge of differentiating between post-surgical changes, radiation necrosis, gliosis, and tumor, submitting these patients to more aggressive therapy and more toxicity. We reviewed the medical records of three patients with primary central nervous system tumors treated at the Children's Hospital Los Angeles who had new false-positive magnetic resonance imaging findings suggestive of tumor recurrence. All of them had complete total resection of primary tumor, had received involved-field radiation therapy, had biopsies confirming absence of viable tumor, and all three patients are long-term survivors. These cases exemplify that not everything that enhances on brain or spine magnetic resonance imaging is viable tumor, and a biopsy should always be considered in the decision-making process in evaluation of potentially recurrent central nervous system tumors in pediatric patients. A step-wise approach for such challenging cases is presented in this article.

11.
PLoS One ; 11(6): e0156907, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27310018

RESUMO

Medulloblastomas are the most common malignant pediatric brain tumor and have been divided into four major molecular subgroups. Animal models that mimic the principal molecular aberrations of these subgroups will be important tools for preclinical studies and allow greater understanding of medulloblastoma biology. We report a new transgenic model of medulloblastoma that possesses a unique combination of desirable characteristics including, among others, the ability to incorporate multiple and variable genes of choice and to produce bioluminescent tumors from a limited number of somatic cells within a normal cellular environment. This model, termed BarTeL, utilizes a Barhl1 homeobox gene promoter to target expression of a bicistronic transgene encoding both the avian retroviral receptor TVA and an eGFP-Luciferase fusion protein to neonatal cerebellar granule neuron precursor (cGNP) cells, which are cells of origin for the sonic hedgehog (SHH) subgroup of human medulloblastomas. The Barhl1 promoter-driven transgene is expressed strongly in mammalian cGNPs and weakly or not at all in mature granule neurons. We efficiently induced bioluminescent medulloblastomas expressing eGFP-luciferase in BarTeL mice by infection of a limited number of somatic cGNPs with avian retroviral vectors encoding the active N-terminal fragment of SHH and a stabilized MYCN mutant. Detection and quantification of the increasing bioluminescence of growing tumors in young BarTeL mice was facilitated by the declining bioluminescence of their uninfected maturing cGNPs. Inclusion of eGFP in the transgene allowed enriched sorting of cGNPs from neonatal cerebella. Use of a single bicistronic avian vector simultaneously expressing both Shh and Mycn oncogenes increased the medulloblastoma incidence and aggressiveness compared to mixed virus infections. Bioluminescent tumors could also be produced by ex vivo transduction of neonatal BarTeL cerebellar cells by avian retroviruses and subsequent implantation into nontransgenic cerebella. Thus, BarTeL mice provide a versatile model with opportunities for use in medulloblastoma biology and therapeutics.


Assuntos
Neoplasias Cerebelares/genética , Cerebelo/metabolismo , Efeito Fundador , Meduloblastoma/genética , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Animais , Animais Recém-Nascidos , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Diferenciação Celular , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Cerebelo/crescimento & desenvolvimento , Cerebelo/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Humanos , Luciferases/genética , Luciferases/metabolismo , Medições Luminescentes , Masculino , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Camundongos , Camundongos Transgênicos , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/patologia , Neurônios/patologia , Regiões Promotoras Genéticas , Receptores Virais/genética , Receptores Virais/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Retroviridae/genética , Retroviridae/metabolismo
12.
Knee Surg Sports Traumatol Arthrosc ; 24(7): 2197-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25448140

RESUMO

The different approaches used in arthroscopic stabilisation of the acromioclavicular joint are well known. However, and despite a great incidence of ectopic pectoralis minor insertion, an alternative choice for the use of arthroscopic portal has not being sufficiently described. Here, we describe a case of acute acromioclavicular dislocation grade III. The arthroscopic stabilisation was achieved using the TightRope (Arthrex, Naples, USA) implant. Through this technique, the approach to the articular portion of the coracoid process can be made intra-articularly or from the subacromial space. We accessed intra-articularly, by opening the rotator interval to reach the coracoid process from the joint cavity. After opening the rotator interval, an ectopic insertion of the pectoralis minor was observed. The choice of approach of the coracoid process from the subacromial space would have complicated the intervention, making it necessary to sever the ectopic tendon to complete the technique, lengthening the surgical time and increasing the chance of complications. For this reason, the use of a standard posterior portal providing intra-articular arthroscopic access through the rotator interval is recommended since the aforementioned anatomical variation is not infrequent. Level of evidence Therapeutic studies-investigating the results of treatment, Level V.


Assuntos
Articulação Acromioclavicular/cirurgia , Artroscopia , Dispositivos de Fixação Ortopédica , Músculos Peitorais/anormalidades , Luxação do Ombro/cirurgia , Adulto , Humanos , Masculino , Luxação do Ombro/classificação
13.
Neuroradiology ; 57(9): 951-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26141852

RESUMO

INTRODUCTION: The specific goal of this study was to determine whether the inclusion of MRS had a measureable and positive impact on the accuracy of pre-surgical MR examinations of untreated pediatric brain tumors over that of MRI alone in clinical practice. METHODS: Final imaging reports of 120 pediatric patients with newly detected brain tumors who underwent combined MRI/MRS examinations were retrospectively reviewed. Final pathology was available in all cases. Group A comprised 60 subjects studied between June 2001 and January 2005, when MRS was considered exploratory and radiologists utilized only conventional MRI to arrive at a diagnosis. For group B, comprising 60 subjects studied between January 2005 and March 2008, the radiologists utilized information from both MRI and MRS. Furthermore, radiologists revisited group A (blind review, time lapse >4 years) to determine whether the additional information from MRS would have altered their interpretation. RESULTS: Sixty-three percent of patients in group A were diagnosed correctly, whereas in 10% the report was partially correct with the final tumor type mentioned (but not mentioned as most likely tumor), while in 27% of cases the reports were wrong. For group B, the diagnoses were correct in 87%, partially correct in 5%, and incorrect in 8% of the cases, which is a significant improvement (p < 0.005). Re-review of combined MRI and MRS of group A resulted 87% correct, 7% partially correct, and 7% incorrect diagnoses, which is a significant improvement over the original diagnoses (p < 0.05). CONCLUSION: Adding MRS to conventional MRI significantly improved diagnostic accuracy in preoperative pediatric patients with untreated brain tumors.


Assuntos
Neoplasias Encefálicas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Imagem Multimodal , Criança , Feminino , Humanos , Masculino
14.
JBJS Case Connect ; 5(2): e55, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-29252708

RESUMO

CASE: We report the case of a fifty-one-year-old woman who underwent an uneventful cubital tunnel release and was admitted five days after surgery with a diagnosis of infection. Despite multiple surgical debridements and prolonged intravenous antibiotic treatment, the wound edges continued to slough and necrose. A delayed diagnosis of postsurgical pyoderma gangrenosum (PG) was made, and corticosteroid and immunosuppressive treatment was administered, with immediate clinical improvement. CONCLUSION: When apparent postoperative infections fail to improve with debridement and antimicrobial treatment, and when accompanied by a fever and severe local pain, nonspecific histopathological findings, and negative microbiological cultures, postsurgical PG should be considered.

15.
J Neurosurg Pediatr ; 12(1): 80-6, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23662931

RESUMO

An intradural somatic-to-autonomic anastomosis, or Xiao procedure, has been described to create a "skin-CNS-bladder" reflex that improves bladder and bowel function in patients with neurogenic bladder and bowel dysfunction. The authors present their experience with a 10-year-old boy with chronic neurogenic bladder and bowel dysfunction related to spinal cord injury who underwent the Xiao procedure. After undergoing a left L-5 ventral root to left S2-3 intradural anastomosis, the patient reported that his bladder and bowel dysfunction improved between 6 and 12 months. Two years after the procedure, however, he reported that there was no change in his bladder or bowel dysfunction as compared with his condition prior to the procedure. Frequent, systematic multidisciplinary evaluations produced conflicting data. Electrophysiological and histological evaluation of the previously performed anastomosis during surgical reexploration 3 years after the Xiao procedure revealed that the anastomosis was in anatomical continuity but neuroma formation had prevented reinnervation. Nerve action potentials were not demonstrable across the anastomosis, and stimulation of the nerve above and below the anastomosis created no bladder or perineal contractions. This is the first clinical report on the outcome of the Xiao procedure in a child with spinal cord injury outside of China. It is impossible to draw broad conclusions about the efficacy of the procedure based on a single patient with no demonstrable benefit. However, future studies should carefully interpret transient improvements in bladder function, urodynamic findings, and the patient's ability to void in response to scratching after the Xiao procedure. The authors' experience with the featured patient, in whom reinnervation could not be demonstrated, suggests that such changes could be related to factors other than the establishment of a skin-CNS-bladder reflex as a result of a somatic-to-autonomic anastomosis.


Assuntos
Vias Autônomas/cirurgia , Reflexo , Rizotomia , Pele/inervação , Traumatismos da Medula Espinal/complicações , Raízes Nervosas Espinhais/cirurgia , Sistema Nervoso Simpático/cirurgia , Bexiga Urinaria Neurogênica/fisiopatologia , Bexiga Urinaria Neurogênica/cirurgia , Bexiga Urinária/inervação , Micção , Anastomose Cirúrgica/métodos , Criança , Doença Crônica , Incontinência Fecal/cirurgia , Humanos , Vértebras Lombares , Masculino , Reoperação , Sacro , Traumatismos da Medula Espinal/fisiopatologia , Raízes Nervosas Espinhais/fisiopatologia , Espaço Subdural , Fatores de Tempo , Resultado do Tratamento , Bexiga Urinária/fisiopatologia , Bexiga Urinaria Neurogênica/etiologia , Incontinência Urinária/cirurgia , Urodinâmica
16.
Childs Nerv Syst ; 29(3): 361-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23250249

RESUMO

BACKGROUND: Microcystic meningioma (MM) is a World Health Organization grade I tumor that is rare in the pediatric population. Meningiomas account for approximately 2-4 % of all childhood central nervous system (CNS) tumors compared to approximately 20 % of all adult CNS tumors. The authors present one of the few confirmed cases of microcystic meningioma in a child and discuss the characteristic radiographic appearance and histological findings. HISTORY: We report the case of an 11-year-old boy who presented with first-time seizure and imaging consistent with brain tumor. There was significant vasogenic edema within the entire right hemisphere, disproportionate to the size of the falcine-based tumor. Histopathological analysis revealed the microcystic subtype of meningioma. DISCUSSION: We review the radiographic characteristics, histopathological findings, and reported pediatric cases of MM in conjunction with our case. CONCLUSION: MM has distinct radiographic characteristics (variable enhancement, lack of a dural tail, and disproportionate vasogenic edema) that can be misinterpreted in the pediatric population, suggesting a more aggressive tumor.


Assuntos
Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Fatores Etários , Criança , Seguimentos , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/diagnóstico por imagem , Meningioma/patologia , Meningioma/cirurgia , Radiografia , Resultado do Tratamento
18.
J Neurooncol ; 107(2): 269-80, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22120608

RESUMO

The paucity of cell culture models for childhood brain tumors prompted us to establish pediatric cell lines for use in biological experiments and preclinical developmental therapeutic studies. Three cell lines were established, CHLA-200 (GBM), CHLA-259 (anaplastic medulloblastoma) and CHLA-266 (atypical teratoid rhabdoid tumor, AT/RT). Consistent with an AT/RT origin, CHLA-266 lacked INI1 expression and had monosomy 22. All lines had unique DNA short tandem repeat "fingerprints" matching that of the patient's tumor tissue and were adherent on tissue culture plastic, but differed in morphology and doubling times. CHLA-200 had a silent mutation in TP53. CHLA-259 and CHLA-266 had wild-type TP53. All three lines were relatively resistant to multiple drugs when compared to the DAOY medulloblastoma cell line, using the DIMSCAN fluorescence digital image microscopy cytotoxicity assay. RNA expression of MYC and MYCN were quantified using RT-PCR (Taqman). CHLA-200 expressed MYC, DAOY and CHLA-259 expressed MYCN, and CHLA-266 expressed both MYCN and MYC. CHLA-200 was only tumorigenic subcutaneously, but CHLA-259 and CHLA-266 were tumorigenic both subcutaneously and in brains of NOD/SCID mice. Immunohistochemistry of the xenografts revealed GFAP staining in CHLA-200 and PGP 9.5 staining in CHLA-259 and CHLA-266 tumors. As expected, INI1 expression was lacking in CHLA-266 (AT/RT). These three new cell lines will provide useful models for research of pediatric brain tumors.


Assuntos
Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral/patologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Glioma/patologia , Adolescente , Animais , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Criança , Modelos Animais de Doenças , Genótipo , Glioma/tratamento farmacológico , Glioma/metabolismo , Humanos , Lactente , Imageamento por Ressonância Magnética , Oncogenes/efeitos dos fármacos , Oncogenes/genética , Pediatria , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Células Tumorais Cultivadas/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Pediatr Blood Cancer ; 56(4): 604-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21298746

RESUMO

BACKGROUND: Types II and III pleuropulmonary blastoma (PPB) are aggressive sarcomas of lung and pleura in young children. Similar to cavoatrial extension of Wilms tumor, PPB may extend into thoracic great vessels and the heart and may involve both venous and arterial circulations and right and left cardiac chambers. Serious embolic complications occur. PROCEDURE: Review International PPB Registry databases and literature (1) for PPB cases with vascular/cardiac extension and (2) for neoadjuvant chemotherapy results in vascular extension cases. RESULTS: Among 179 Registry-confirmed and approximately 200 literature Type II and III PPB cases, 11 examples (approximately 3%) of great vessel/cardiac extension were identified; 1 case is presented in detail. Nine cases involved the left circulation, one the right and one both. Various radiographic techniques including echography, computed tomography and gated magnetic resonance imaging identified vascular tumor. Seven children had arterial embolic events: cerebrovascular accidents (six, including one femoral artery occlusion) and acute aortic occlusion (1). Six of these seven died from complications that may be attributed to vascular involvement. In three of four children with vascular involvement, neoadjuvant chemotherapy lessened the involvement; in one the effect could not be assessed. None of these four had embolic events. Effect on survival could not be assessed due to small numbers. CONCLUSIONS: Involvement of thoracic great vessels and the heart is a serious complication of PPB, with fatal embolic complications possible. Radiographic evaluation of the central circulation should be performed in children with suspected or diagnosed PPB to identify this complication.


Assuntos
Neoplasias Cardíacas/patologia , Neoplasias Pulmonares/patologia , Células Neoplásicas Circulantes/patologia , Neoplasias Vasculares/patologia , Pré-Escolar , Feminino , Humanos , Miocárdio/patologia , Invasividade Neoplásica , Artéria Pulmonar/patologia , Blastoma Pulmonar/patologia , Veias Pulmonares/patologia , Veias Cavas/patologia
20.
J Biol Chem ; 286(3): 2183-93, 2011 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21071448

RESUMO

Outer membrane protein A (OmpA) has been implicated as an important virulence factor in several gram-negative bacterial infections such as Escherichia coli K1, a leading cause of neonatal meningitis associated with significant mortality and morbidity. In this study, we generated E. coli K1 mutants that express OmpA in which three or four amino acids from various extracellular loops were changed to alanines, and we examined their ability to survive in several immune cells. We observed that loop regions 1 and 2 play an important role in the survival of E. coli K1 inside neutrophils and dendritic cells, and loop regions 1 and 3 are needed for survival in macrophages. Concomitantly, E. coli K1 mutants expressing loop 1 and 2 mutations were unable to cause meningitis in a newborn mouse model. Of note, mutations in loop 4 of OmpA enhance the severity of the pathogenesis by allowing the pathogen to survive better in circulation and to produce high bacteremia levels. These results demonstrate, for the first time, the roles played by different regions of extracellular loops of OmpA of E. coli K1 in the pathogenesis of meningitis and may help in designing effective preventive strategies against this deadly disease.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Escherichia coli/metabolismo , Escherichia coli/patogenicidade , Meningite devida a Escherichia coli/metabolismo , Viabilidade Microbiana , Animais , Bacteriemia/genética , Bacteriemia/metabolismo , Bacteriemia/microbiologia , Proteínas da Membrana Bacteriana Externa/genética , Células Dendríticas/metabolismo , Células Dendríticas/microbiologia , Escherichia coli/genética , Humanos , Macrófagos/metabolismo , Macrófagos/microbiologia , Meningite devida a Escherichia coli/genética , Meningite devida a Escherichia coli/microbiologia , Camundongos , Camundongos Knockout , Mutação , Neutrófilos/metabolismo , Neutrófilos/microbiologia , Estrutura Secundária de Proteína
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