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1.
Br J Haematol ; 190(3): 450-457, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32307711

RESUMO

The pathophysiology of sickle cell disease (SCD) includes vasculopathy as well as anaemia. Elevated plasma homocysteine is a risk factor for vascular disease and may be associated with increased risk of vascular complications in SCD patients. In the present study, microvascular characteristics were assessed in the bulbar conjunctiva of 18 paediatric and 18 adult SCD patients, using the non-invasive technique of computer-assisted intravital microscopy. A vasculopathy severity index (SI) was computed to quantify the degree of microvasculopathy in each patient. Plasma homocysteine and several of its determinants [serum folate and vitamin B12, plasma pyridoxal-5'-phosphate (vitamin B6 status) and creatinine (kidney function)] were measured. Age was strongly correlated with microvasculopathy in the SCD patients, with the SI increasing about 0·1 unit per one-year increase in age (P < 0·001). After adjusting for age, gender, B-vitamin status and creatinine, homocysteine concentration was directly correlated with severity index (P < 0·05). Age and homocysteine concentration were independent predictors of microvasculopathy in SCD patients. It remains to be determined whether lowering homocysteine concentrations using appropriate B-vitamin supplements (folate and vitamins B12 and B6) - particularly if started early in life - could ameliorate microvasculopathy and its associated complications in SCD patients.


Assuntos
Anemia Falciforme/fisiopatologia , Homocisteína/sangue , Microcirculação , Microangiopatias Trombóticas/etiologia , Adolescente , Adulto , Anemia Falciforme/sangue , Criança , Pré-Escolar , Creatina/sangue , Ácido Fólico/sangue , Humanos , Microscopia Intravital , Pessoa de Meia-Idade , Fosfato de Piridoxal/sangue , Índice de Gravidade de Doença , Microangiopatias Trombóticas/sangue , Microangiopatias Trombóticas/fisiopatologia , Vitamina B 12/sangue
2.
J Clin Oncol ; 34(25): 3031-8, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27400942

RESUMO

PURPOSE: The use of radiographic response as the primary end point in phase II osteosarcoma trials may limit optimal detection of treatment response because of the calcified tumor matrix. We performed this study to determine if time to progression could be used as an end point for subsequent studies. PATIENTS AND METHODS: We performed a retrospective analysis of outcome for patients with recurrent/refractory osteosarcoma enrolled in one of seven phase II trials conducted by the Children's Oncology Group and predecessor groups from 1997 to 2007. All trials used RECIST or WHO radiographic response criteria and the primary end point of response rate. The following potential prognostic factors-age, trial, number of prior chemotherapy regimens, sex, and race/ethnicity-were evaluated for their impact on event-free survival (EFS). We used data from a phase II study (AOST0221) of patients with osteosarcoma who were given inhaled granulocyte-macrophage colony-stimulating factor with first pulmonary recurrence who had an EFS as well as biologic end point to determine the historical disease control rate for patients with fully resected disease. RESULTS: In each included trial, the drugs tested were determined to be inactive on the basis of radiographic response rates. The EFS for 96 patients with osteosarcoma and measurable disease was 12% at 4 months (95% CI, 6% to 19%). There was no significant difference in EFS across trials according to number of prior treatment regimens or patient age, sex, and ethnicity. The 12-month EFS for the 42 evaluable patients enrolled in AOST0221 was 20% (95% CI, 10% to 34%). CONCLUSION: The EFS was uniformly poor for children with recurrent/refractory osteosarcoma in these single-arm phase II trials. We have now constructed baseline EFS outcomes that can be used as a comparison for future phase II trials for recurrent osteosarcoma.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/tratamento farmacológico , Ensaios Clínicos Fase II como Assunto/métodos , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/tratamento farmacológico , Adolescente , Criança , Intervalo Livre de Doença , Determinação de Ponto Final , Feminino , Humanos , Masculino , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
3.
Pediatr Dev Pathol ; 19(4): 338-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26555328

RESUMO

Neonatal intestinal masses with spindle cell morphology have broad differential diagnoses and require a multidisciplinary approach to make the final diagnosis. Spindle cell masses with heterotopic cartilage in the gastrointestinal tract are very rare, and, to our knowledge, have not previously been reported in the neonate. Here we present a case of intestinal primitive spindle cell neoplasm with extensive heterotopic cartilage that manifested initially as acute abdomen in a 6-day-old term infant. Plain radiography demonstrated pneumoperitoneum, prompting diagnostic laparotomy that identified a perforated mass involving the midileum. Histologic and immunohistochemical examination demonstrated an infiltrative spindle cell tumor most compatible with infantile fibrosarcoma (IFS) by a process of exclusion, with nodules of mature heterotopic cartilage. Additional staging studies did not reveal any evidence of residual or metastatic disease. Recognition of this rare variant of IFS will aid in differentiation from other neonatal intestinal mesenchymal tumors.


Assuntos
Abdome Agudo/etiologia , Cartilagem , Coristoma , Fibrossarcoma/patologia , Neoplasias do Íleo/congênito , Neoplasias do Íleo/patologia , Doenças do Recém-Nascido/patologia , Fibrossarcoma/congênito , Humanos , Íleo/patologia , Recém-Nascido , Masculino
4.
J Pediatr Hematol Oncol ; 34(3): 169-74, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22278200

RESUMO

Periodic blood exchange transfusion is a treatment modality commonly used to manage pediatric sickle cell anemia at the University of California Davis Medical Center. The goal of exchange transfusion therapy is to ameliorate vasoocclusion and improve tissue perfusion by removing sickled red blood cells and introducing normal red blood cells. Using computer-assisted intravital microscopy, pretransfusion and posttransfusion microvascular characteristics were analyzed. In this study, the bulbar conjunctiva exhibited a "blanched" avascular appearance in all 6 pediatric sickle cell anemia patients before transfusion, indicative of tissue hypoperfusion and ischemia. Immediately after transfusion, substantial improvement in vascularization and tissue perfusion resulted, reflected by the enhanced appearance of capillaries and arterioles. In addition, a decrease in red cell velocity was observed. These observations provide evidence that exchange transfusion therapy is beneficial in ameliorating vasoocclusion and improving tissue perfusion. However, with the paradoxical posttransfusion decrease in red cell velocity presumably due to induced hyperviscosity from the large transfusion volume, blood flow is still impaired. This decreased velocity may thwart efforts to improve oxygen delivery through transfusion and may, to some extent, promote vasoocclusion instead. This paradoxical result warrants further investigation on the effects of transfusion volume and viscosity in the exchange transfusion process.


Assuntos
Anemia Falciforme/sangue , Anemia Falciforme/terapia , Transfusão Total , Microcirculação , Microscopia de Vídeo , Adolescente , Criança , Pré-Escolar , Humanos , Estudos Longitudinais , Prognóstico
5.
Pediatr Blood Cancer ; 58(6): 885-90, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21796766

RESUMO

BACKGROUND: HSP90 plays a central role in stabilizing client proteins involved in malignant processes. SNX-2112 is an orally administered potent HSP90 inhibitor that has demonstrated pre-clinical anti-tumor activity in adult malignancies. As many childhood tumors depend upon HSP90 client proteins, we sought to test the pre-clinical efficacy of SNX-2112 in a panel of pediatric cancer cell lines both as a single-agent and in combination with cisplatin (CP). PROCEDURE: Eight cell lines (from osteosarcoma, neuroblastoma, hepatoblastoma, and lymphoma) were studied. Short- and long-term effects of SNX-2112 were assessed by MTT and clonogenic assays. Cell cycling was measured using flow cytometry. Status of HSC70, HSP72, AKT1, C-Raf, and PARP was assessed by immunoblotting. Efficacy of SNX-2112 in combination with CP was assessed using median-effect analysis. RESULTS: Cell lines studied demonstrated sensitivity to SNX-2112 with IC(50) values ranging from 10-100 nM. Low dose treatments (12 nM) resulted in a cytostatic response with a minimal increase in sub-G1 content. A higher dose (70 nM) exhibited a more prolonged inhibition and larger sub-G1 accumulation. Observed levels of AKT1 and C-Raf were markedly reduced over time along with an increase in PARP cleavage. In concurrently administered combination treatments, SNX-2112 and CP synergistically inhibited cell growth. CONCLUSIONS: SNX-2112 showed marked single-agent activity in pediatric cancer cell lines with downstream effects on HSP90 client proteins. The combination of SNX-2112 and CP showed synergistic activity in two cell lines tested. Further studies of HSP90 inhibitors such as SNX-2112 as a single agent or in combination with chemotherapy are warranted in pediatric cancer.


Assuntos
Antineoplásicos/farmacologia , Hepatoblastoma , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Linfoma , Neuroblastoma , Osteossarcoma , Apoptose/efeitos dos fármacos , Western Blotting , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Sinergismo Farmacológico , Citometria de Fluxo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Humanos
6.
Am J Med Genet A ; 155A(1): 120-5, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21204218

RESUMO

We report on a 5-year-old Caucasian female with multiple anomalies whose deletion, 46,XX,del(21)(q22.11q22.13), was determined by a 105K oligonucleotide-based microarray. This case is a unique deletion that mimicked Fanconi anemia (combination of thrombocytopenia, thumb anomalies, congenital heart defects, borderline small head circumference, strabismus, hydronephrosis, and significant developmental delay) but testing for Fanconi anemia was negative, as was testing for a wide array of genetic/metabolic conditions. Microarray testing done at 5 months failed to demonstrate the interstitial deletion that was found on a newer generation microarray test performed after 3 years of age. When compared to other reported cases of partial monosomy 21q, the unique features of this case include: (1) cleft palate, although high palate is reported in other cases; (2) neonatal thrombocytopenia requiring platelet transfusion; (3) a platelet function defect, reported previously as platelet storage pool defect as part of a familial platelet disorder; and (4) an immune function defect. Similar to other reported patients with terminal 21q deletion, this child had significant developmental delay, and feeding and growth problems. This case also highlights the ability for newer technology microarrays to identify small interstitial deletions previously missed by an earlier version microarray. The advances in the microarray technologies are allowing us to better define new phenotypes and leading to the identification of a diagnosis for many patients who have been previously undiagnosed. Review of the genes involved in these novel deletions allows the caring physician to design surveillance strategies that are custom-designed for these unique patients.


Assuntos
Anormalidades Múltiplas/genética , Anemia de Fanconi/genética , Fenótipo , Anormalidades Múltiplas/patologia , Transtornos Plaquetários/genética , Transtornos Plaquetários/patologia , Criança , Deleção Cromossômica , Cromossomos Humanos Par 21/genética , Fissura Palatina/genética , Fissura Palatina/patologia , Diagnóstico Diferencial , Anemia de Fanconi/patologia , Feminino , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Trombocitopenia Neonatal Aloimune/genética , Trombocitopenia Neonatal Aloimune/patologia
7.
Am J Hematol ; 85(11): 899-901, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20872552

RESUMO

The conjunctival microcirculation in 14 pediatric and eight adult sickle cell anemia (SCA) patients was studied using computer-assisted intravital microscopy. The bulbar conjunctiva in SCA patients in both age groups exhibited a blanched/avascular appearance characterized by decreased vascularity. SCA patients from both age groups had many of the same abnormal morphometric [vessel diameter, vessel distribution, morphometry (shape), tortuosity, arteriole:venule (A:V) ratio, and hemosiderin deposits] and dynamic [vessel sludging/sludged flow, boxcar blood (trickled) flow, and abnormal flow velocity] abnormalities. A severity index (SI) was computed to quantify the degree of vasculopathy for comparison between groups. The severity of vasculopathy differed significantly between the pediatric and adult patients (SI: 4.2 ± 1.8 vs. 6.6 ± 2.4; P = 0.028), indicative of a lesser degree of overall severity in the pediatric patients. Specific abnormalities that were less prominent in the pediatric patients included abnormal vessel morphometry and tortuosity. Sludged flow, abnormal vessel distribution, abnormal A:V ratio, and boxcar flow appeared in high prevalence in both age groups. The results indicate that SCA microvascular abnormalities develop in childhood and the severity of vasculopathy likely progresses with age. Intervention and effective treatment/management modalities should target pediatric patients to ameliorate, slow down, or prevent progressive microvascular deterioration.


Assuntos
Anemia Falciforme/fisiopatologia , Microvasos/patologia , Adolescente , Adulto , Fatores Etários , Velocidade do Fluxo Sanguíneo , Criança , Túnica Conjuntiva/irrigação sanguínea , Humanos , Microcirculação , Microvasos/fisiopatologia , Pessoa de Meia-Idade
8.
Am J Med Genet A ; 149A(10): 2265-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19764022

RESUMO

We report on a 5-year-old male with expressive language delay, developmental delay, short stature, and facial anomalies consistent with Floating-Harbor syndrome (FHS). In addition, he developed an intramedullary ganglioglioma. This is the first reported case of a tumor associated with FHS, and may represent an as yet undefined genetic link between spinal cord tumors and FHS, adding this syndrome to the growing list of disorders with a predisposition for tumor development.


Assuntos
Anormalidades Craniofaciais/complicações , Deficiências do Desenvolvimento/complicações , Ganglioglioma/complicações , Transtornos do Crescimento/complicações , Neoplasias da Medula Espinal/complicações , Pré-Escolar , Anormalidades Craniofaciais/diagnóstico , Deficiências do Desenvolvimento/diagnóstico , Ganglioglioma/diagnóstico , Transtornos do Crescimento/diagnóstico , Humanos , Transtornos do Desenvolvimento da Linguagem/complicações , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Masculino , Neoplasias da Medula Espinal/diagnóstico , Síndrome
10.
Anal Chem ; 80(6): 2180-7, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18260656

RESUMO

Currently, a combination of technologies is typically required to assess the malignancy of cancer cells. These methods often lack the specificity and sensitivity necessary for early, accurate diagnosis. Here we demonstrate using clinical samples the application of laser trapping Raman spectroscopy as a novel approach that provides intrinsic biochemical markers for the noninvasive detection of individual cancer cells. The Raman spectra of live, hematopoietic cells provide reliable molecular fingerprints that reflect their biochemical composition and biology. Populations of normal T and B lymphocytes from four healthy individuals and cells from three leukemia patients were analyzed, and multiple intrinsic Raman markers associated with DNA and protein vibrational modes have been identified that exhibit excellent discriminating power for cancer cell identification. A combination of two multivariate statistical methods, principal component analysis (PCA) and linear discriminant analysis (LDA), was used to confirm the significance of these markers for identifying cancer cells and classifying the data. The results indicate that, on average, 95% of the normal cells and 90% of the patient cells were accurately classified into their respective cell types. We also provide evidence that these markers are unique to cancer cells and not purely a function of differences in their cellular activation.


Assuntos
Separação Celular , Leucemia/patologia , Análise Espectral Raman/métodos , Linfócitos B/citologia , Humanos , Reprodutibilidade dos Testes , Linfócitos T/citologia
12.
Biophys J ; 90(2): 648-56, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16239327

RESUMO

Current methods for identifying neoplastic cells and discerning them from their normal counterparts are often nonspecific, slow, biologically perturbing, or a combination thereof. Here, we show that single-cell micro-Raman spectroscopy averts these shortcomings and can be used to discriminate between unfixed normal human lymphocytes and transformed Jurkat and Raji lymphocyte cell lines based on their biomolecular Raman signatures. We demonstrate that single-cell Raman spectra provide a highly reproducible biomolecular fingerprint of each cell type. Characteristic peaks, mostly due to different DNA and protein concentrations, allow for discerning normal lymphocytes from transformed lymphocytes with high confidence (p << 0.05). Spectra are also compared and analyzed by principal component analysis to demonstrate that normal and transformed cells form distinct clusters that can be defined using just two principal components. The method is shown to have a sensitivity of 98.3% for cancer detection, with 97.2% of the cells being correctly classified as belonging to the normal or transformed type. These results demonstrate the potential application of confocal micro-Raman spectroscopy as a clinical tool for single cancer cell detection based on intrinsic biomolecular signatures, therefore eliminating the need for exogenous fluorescent labeling.


Assuntos
Biofísica/métodos , Células-Tronco Hematopoéticas/citologia , Neoplasias/metabolismo , Análise Espectral Raman/métodos , Linfócitos B/metabolismo , Adesão Celular , Linhagem Celular , Linhagem Celular Transformada , DNA/química , Hematopoese , Sistema Hematopoético , Humanos , Células Jurkat , Leucócitos Mononucleares/metabolismo , Linfócitos/metabolismo , Microscopia Confocal , Microscopia de Fluorescência , Análise de Componente Principal , RNA/química , Reprodutibilidade dos Testes , Espectrofotometria , Fatores de Tempo
14.
Ann Neurol ; 58(4): 594-604, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16178029

RESUMO

We report four young women who developed acute psychiatric symptoms, seizures, memory deficits, decreased level of consciousness, and central hypoventilation associated with ovarian teratoma (OT) and cerebrospinal fluid (CSF) inflammatory abnormalities. Three patients recovered with treatment of the tumor or immunosuppression and one died of the disorder. Five other OT patients with a similar syndrome and response to treatment have been reported. Our patients' serum or CSF showed immunolabeling of antigens that were expressed at the cytoplasmic membrane of hippocampal neurons and processes and readily accessed by antibodies in live neurons. Immunoprobing of a hippocampal-expression library resulted in the isolation of EFA6A, a protein that interacts with a member of the two-pore-domain potassium channel family and is involved in the regulation of the dendritic development of hippocampal neurons. EFA6A-purified antibodies reproduced the hippocampal immunolabeling of all patients' antibodies and colocalized with them at the plasma membrane. These findings indicate that in a young woman with acute psychiatric symptoms, seizures, and central hypoventilation, a paraneoplastic immune-mediated syndrome should be considered. Recognition of this disorder is important because despite the severity of the symptoms, patients usually recover. The location and function of the isolated antigen suggest that the disorder is directly mediated by antibodies.


Assuntos
Encefalite/etiologia , Hipoventilação/etiologia , Transtornos Mentais/etiologia , Neoplasias Ovarianas/complicações , Teratoma/complicações , Adolescente , Adulto , Animais , Anticorpos Antineoplásicos/metabolismo , Western Blotting/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Células Cultivadas , Feminino , Fluordesoxiglucose F18/farmacocinética , Regulação Neoplásica da Expressão Gênica/fisiologia , Hipocampo/citologia , Humanos , Imunoglobulina G/metabolismo , Imuno-Histoquímica/métodos , Imageamento por Ressonância Magnética/métodos , Neurônios/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Ratos , Fatores de Tempo
15.
J Palliat Med ; 8(3): 486-9, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15992188

RESUMO

Historically, the concept of palliative care has been limited to hospice and end-of-life services. Recently, palliative care has been expanded to emphasize its integration throughout an illness. We suggest that palliative care provides an opportunity to prevent illness. Palliative care providers can effectively reduce the risk of illness in families by employing methods and strategies of preventive medicine. We illustrate three such cases. Patients and survivors may benefit from appropriate recognition and referral to prevent potential medical, social, and psychological problems. For preventive medicine to become fully exploited by palliative care providers, curricula will need to be developed. Risk assessment indicators of heritable and acquired conditions will define core functions of this educational process. Relevant topics should encompass basic preventive medicine methods, methods to disseminate assigned risk to the palliative care team, and referral mechanisms to specialists with expertise in the identified area(s) of concern. Opportunities to integrate preventive care into end-of-life services will create a new dimension for comprehensive palliative care.


Assuntos
Cuidados Paliativos/organização & administração , Medicina Preventiva , Síndrome da Imunodeficiência Adquirida/enfermagem , Adulto , Continuidade da Assistência ao Paciente , Feminino , Humanos , Doença de Huntington/enfermagem , Masculino , Melanoma/enfermagem , Melanoma/patologia , Pessoa de Meia-Idade , Metástase Neoplásica , Estados Unidos
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