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1.
Clin Colon Rectal Surg ; 34(1): 62-68, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33536851

RESUMO

Rectal prolapse is a debilitating condition that often results in impaired quality of life. Posterior compartment defects including rectal prolapse and rectal intussusception are often associated with middle and anterior compartment prolapse and require a multicompartment approach to treatment. In recent years, ventral rectopexy, with or without sacrocolpopexy for combined middle compartment prolapse, has emerged as a safe and effective method of treatment for rectal prolapse. In this article, we aim to review the etiology of rectal prolapse and intussusception, describe the indications and workup for surgery, discuss technical aspects of ventral rectopexy alone and in combination with sacrocolpopexy, review potential surgical complications, and describe the reported outcomes of the surgery.

2.
PLoS One ; 7(5): e37218, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22606352

RESUMO

Sphingosine-1-phosphate (S1P) activates a widely expressed family of G protein-coupled receptors, serves as a muscle trophic factor and activates muscle stem cells called satellite cells (SCs) through unknown mechanisms. Here we show that muscle injury induces dynamic changes in S1P signaling and metabolism in vivo. These changes include early and profound induction of the gene encoding the S1P biosynthetic enzyme SphK1, followed by induction of the catabolic enzyme sphingosine phosphate lyase (SPL) 3 days later. These changes correlate with a transient increase in circulating S1P levels after muscle injury. We show a specific requirement for SphK1 to support efficient muscle regeneration and SC proliferation and differentiation. Mdx mice, which serve as a model for muscular dystrophy (MD), were found to be S1P-deficient and exhibited muscle SPL upregulation, suggesting that S1P catabolism is enhanced in dystrophic muscle. Pharmacological SPL inhibition increased muscle S1P levels, improved mdx muscle regeneration and enhanced SC proliferation via S1P receptor 2 (S1PR2)-dependent inhibition of Rac1, thereby activating Signal Transducer and Activator of Transcription 3 (STAT3), a central player in inflammatory signaling. STAT3 activation resulted in p21 and p27 downregulation in a S1PR2-dependent fashion in myoblasts. Our findings suggest that S1P promotes SC progression through the cell cycle by repression of cell cycle inhibitors via S1PR2/STAT3-dependent signaling and that SPL inhibition may provide a therapeutic strategy for MD.


Assuntos
Lisofosfolipídeos/farmacologia , Distrofia Muscular de Duchenne/tratamento farmacológico , Distrofia Muscular de Duchenne/metabolismo , Receptores de Lisoesfingolipídeo/metabolismo , Fator de Transcrição STAT3/metabolismo , Células Satélites de Músculo Esquelético/efeitos dos fármacos , Células Satélites de Músculo Esquelético/metabolismo , Esfingosina/análogos & derivados , Animais , Proliferação de Células , Feminino , Lisofosfolipídeos/deficiência , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Camundongos Knockout , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/lesões , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Distrofia Muscular de Duchenne/patologia , Fosfotransferases (Aceptor do Grupo Álcool)/deficiência , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Regeneração/efeitos dos fármacos , Regeneração/fisiologia , Células Satélites de Músculo Esquelético/patologia , Transdução de Sinais/efeitos dos fármacos , Esfingosina/deficiência , Esfingosina/farmacologia , Receptores de Esfingosina-1-Fosfato
3.
J Pediatr Surg ; 47(1): 36-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22244389

RESUMO

BACKGROUND/PURPOSE: Congenital pulmonary airway malformations (CPAM) are rare lesions often diagnosed during routine prenatal ultrasound. The presence of hydrops fetalis is an indicator of poor prognosis. Here we present a retrospective review of fetuses undergoing either open fetal surgery or steroids for predominantly microcystic CPAM with hydrops fetalis. METHOD: A retrospective review of patients undergoing open fetal surgery or steroids for CPAM at our institution was performed. The primary outcome was survival. RESULTS: A retrospective review of all patients referred to our institution with the diagnosis of CPAM was performed. Fetuses with predominantly microcystic CPAM and the presence of hydrops fetalis treated with steroid or surgery were included. Thirteen patients were treated with steroids, and 11 patients underwent open fetal surgery. In the steroid group 12 (92%) of 13 fetuses survived to delivery versus 9 (82%) of 11 in the open fetal surgery group. Only 5 (56%) of 9 of the patients in the open fetal surgery group survived to neonatal discharge compared to 10 (83%) of 12 in the steroid group. CONCLUSIONS: In the present retrospective study, improved survival was seen in fetuses with hydrops fetalis and predominantly microcystic CPAM treated with steroids when compared with open fetal surgery. Steroids should be considered for first-line therapy in these cases.


Assuntos
Betametasona/uso terapêutico , Feto/cirurgia , Glucocorticoides/uso terapêutico , Hidropisia Fetal/tratamento farmacológico , Hidropisia Fetal/cirurgia , Pulmão/anormalidades , Pulmão/cirurgia , Feminino , Humanos , Gravidez , Estudos Retrospectivos
4.
Anticancer Agents Med Chem ; 11(9): 782-93, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21707493

RESUMO

Sphingosine-1-phosphate (S1P) is a bioactive lipid with diverse functions including the promotion of cell survival, proliferation and migration, as well as the regulation of angiogenesis, inflammation, immunity, vascular permeability and nuclear mechanisms that control gene transcription. S1P is derived from metabolism of ceramide, which itself has diverse and generally growth-inhibitory effects through its impact on downstream targets involved in regulation of apoptosis, senescence and cell cycle progression. Regulation of ceramide, S1P and the biochemical steps that modulate the balance and interconversion of these two lipids are major determinants of cell fate, a concept referred to as the "sphingolipid rheostat." There is abundant evidence that the sphingolipid rheostat plays a role in the origination, progression and drug resistance patterns of hematopoietic malignancies. The pathway has also been exploited to circumvent the problem of chemotherapy resistance in leukemia and lymphoma. Given the broad effects of sphingolipids, targeting multiple steps in the metabolic pathway may provide possible therapeutic avenues. However, new observations have revealed that sphingolipid signaling effects are more complex than previously recognized, requiring a revision of the sphingolipid rheostat model. Here, we summarize recent insights regarding the sphingolipid metabolic pathway and its role in hematopoietic malignancies.


Assuntos
Neoplasias Hematológicas/metabolismo , Transdução de Sinais , Esfingolipídeos/metabolismo , Animais , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Transdução de Sinais/efeitos dos fármacos
5.
J Pediatr Surg ; 40(1): 251-5, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15868593

RESUMO

PURPOSE: Desmoplastic small round cell tumors (DSRCTs) are rare aggressive neoplasms that frequently present with large symptomatic intraabdominal masses. We examined the effects of multimodal therapy including induction chemotherapy, aggressive surgical debulking, and external beam radiotherapy on patients with DSRCT. METHODS: Institutional Review Board permission was obtained. Sixty-six patients were diagnosed by histology, immunohistochemistry, and or cytogenetics as having DSRCT at our institution from July 1, 1972, to July 1, 2003. Data were collected on patient demographics, presenting symptoms, tumor location and extent, treatment regimen, and overall survival. RESULTS: A majority of patients were male (91%), Caucasian (85%), and with a median age of 19 (7-58) years old at diagnosis. The most common presenting complaint was an intraabdominal mass (64%). In 63 patients (96%), the primary tumor was located in the abdomen or pelvis. Thirty-three (50%) had positive lymph nodes and 27 (41%) had distant parenchymal metastases at diagnosis. Overall, 3- and 5-year survivals were 44% and 15%, respectively. Twenty-nine of these patients (44%) underwent induction chemotherapy (P6), surgical debulking, and radiotherapy. Three-year survival was 55% in those receiving chemotherapy, surgery, and radiotherapy vs 27% when all 3 modalities were not used (P < .02). Gross tumor resection was highly significant in prolonging overall survival; 3-year survival was 58% in patients treated with gross tumor resection compared to no survivors past 3 years in the nonresection cohort (P < .00001). Ten patients (15%) have no evidence of disease with a median follow-up of 2.4 years (range, 0.4-11.2 years). CONCLUSIONS: Multimodal therapy results in improved survival in patients with DSRCT. Aggressive surgical resection of these extensive intraabdominal neoplasms correlates with improved patient outcome.


Assuntos
Sarcoma de Células Pequenas/terapia , Neoplasias de Tecidos Moles/terapia , Neoplasias Abdominais/patologia , Neoplasias Abdominais/cirurgia , Neoplasias Abdominais/terapia , Adolescente , Adulto , Antineoplásicos/uso terapêutico , Criança , Terapia Combinada , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Pélvicas/patologia , Neoplasias Pélvicas/cirurgia , Neoplasias Pélvicas/terapia , Radioterapia , Sarcoma de Células Pequenas/patologia , Sarcoma de Células Pequenas/cirurgia , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/cirurgia , Procedimentos Cirúrgicos Operatórios , Análise de Sobrevida , Neoplasias Testiculares/patologia , Neoplasias Testiculares/cirurgia , Neoplasias Testiculares/terapia , Neoplasias Torácicas/patologia , Neoplasias Torácicas/cirurgia , Neoplasias Torácicas/terapia , Resultado do Tratamento
6.
J Pediatr Hematol Oncol ; 27(5): 254-8, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15891559

RESUMO

This study describes the outcomes of children treated with combinations of temozolomide and radiation therapy for various aggressive central nervous system malignancies. Their age at diagnosis ranged from 1 to 15 years. Patients with focal disease were treated with concomitant temozolomide (daily 75 mg/m) and three-dimensional conformal radiotherapy in a dose that ranged from 50 to 54 Gy, followed by temozolomide (200 mg/m/d x 5 days/month in three patients, 150 mg/m x 5 days/ month in one patient). Patients with disseminated disease were treated with craniospinal radiation (39.6 Gy) before conformal boost. One patient received temozolomide (200 mg/m x 5 days/month) before craniospinal radiation, and one patient received temozolomide (daily 95 mg/m) concomitant with craniospinal radiation and a radiosurgical boost, followed by temozolomide (200 mg/m x 5 days/month). Three patients achieved a partial response during treatment, with two of these patients dying of progressive disease after treatment. One patient has no evidence of disease. Three patients achieved stable disease, with one of these patients dying of progressive disease after treatment. Toxicities observed included low-grade neutropenia, thrombocytopenia, and lymphopenia. The combination of temozolomide and radiotherapy appears to be well tolerated in a variety of treatment schemas for aggressive pediatric central nervous system malignancies. This information is of particular use in designing future studies, given the recent positive results in a randomized study examining the use of temozolomide concomitant with radiation in the treatment of adult glioblastoma.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/radioterapia , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Adolescente , Neoplasias do Sistema Nervoso Central/diagnóstico , Criança , Pré-Escolar , Terapia Combinada , Evolução Fatal , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Temozolomida
7.
Proc Natl Acad Sci U S A ; 100(9): 5491-6, 2003 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-12702772

RESUMO

In the visual system, differential gene expression underlies development of the anterior-posterior and dorsal-ventral axes. Here we present the results of a microarray screen to identify genes differentially expressed in the developing retina. We assayed gene expression in nasal (anterior), temporal (posterior), dorsal, and ventral embryonic mouse retina. We used a statistical method to estimate gene expression between different retina regions. Genes were clustered according to their expression pattern and were ranked within each cluster. We identified groups of genes expressed in gradients or with restricted patterns of expression as verified by in situ hybridization. A common theme for the identified genes is the differential expression in the dorsal-ventral axis. By analyzing gene expression patterns, we provide insight into the molecular organization of the developing retina.


Assuntos
Perfilação da Expressão Gênica , Retina/metabolismo , Animais , Sequência de Bases , Primers do DNA , Camundongos , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Retina/enzimologia
8.
Neuron ; 36(3): 417-34, 2002 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-12408845

RESUMO

As an approach toward understanding the molecular mechanisms of neuronal differentiation, we utilized DNA microarrays to elucidate global patterns of gene expression during pontocerebellar development. Through this analysis, we identified groups of genes specific to neuronal precursor cells, associated with axon outgrowth, and regulated in response to contact with synaptic target cells. In the cerebellum, we identified a phase of granule cell differentiation that is independent of interactions with other cerebellar cell types. Analysis of pontine gene expression revealed that distinct programs of gene expression, correlated with axon outgrowth and synapse formation, can be decoupled and are likely influenced by different cells in the cerebellar target environment. Our approach provides insight into the genetic programs underlying the differentiation of specific cell types in the pontocerebellar projection system.


Assuntos
Diferenciação Celular/genética , Cerebelo/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/genética , Vias Neurais/crescimento & desenvolvimento , Neurônios/metabolismo , Ponte/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Células Cultivadas , Cerebelo/citologia , Cerebelo/metabolismo , Ciclina D2 , Ciclinas/genética , Feminino , Masculino , Camundongos , Camundongos Mutantes Neurológicos , Vias Neurais/citologia , Vias Neurais/metabolismo , Neuroglia/citologia , Neuroglia/metabolismo , Neurônios/citologia , Análise de Sequência com Séries de Oligonucleotídeos , Ponte/citologia , Ponte/metabolismo , Células de Purkinje/citologia , Células de Purkinje/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de GABA/genética , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Transcrição/genética
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