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1.
Front Plant Sci ; 14: 1155755, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37152121

RESUMEN

Early fruit growth in peach is characterized by cell production. Cytokinins have established roles in regulating cell division and may regulate cell production during early fruit growth. However, the role of active cytokinins and regulation of their metabolism are not well characterized in the peach fruit. In this study, fruit growth parameters, concentrations of active cytokinin bases and a cytokinin riboside, and expression of three key cytokinin metabolism-related gene families were determined during early fruit growth. Early fruit growth was associated with intensive cell production until around 40 days after full bloom. During the early stages of this period, trans-zeatin (tZ), isopentenyladenine (iP), dihydrozeatin (DHZ) and tZ-riboside (tZR), displayed higher abundance which declined rapidly by 3.5- to 16-fold during the later stages. Changes in concentration of active cytokinin bases were consistent with roles for them in regulating cell production. Expression analyses of members of cytokinin biosynthesis-related gene families, ISOPENTENYL TRANSFERASE (IPT) and LONELY GUY (LOG), further indicated that mechanisms of synthesis of cytokinin metabolites and their activation are functional within the fruit pericarp. Changes in expression of multiple members of the LOG family paralleled changes in active cytokinin concentrations. Specifically, transcript abundance of LOG3 and LOG8 were correlated with concentrations of tZ, and iP and DHZ, respectively, suggesting that the direct activation pathway is an important route for active cytokinin base synthesis during early fruit development. Transcript abundance of two CYTOKININ OXIDASE (CKX) genes, CKX1 and CKX2, was consistent with roles in cytokinin catabolism during later stages of early fruit growth. Together, these data support a role for active cytokinins synthesized in the fruit pericarp in regulating early fruit growth in peach.

2.
Acta Neuropathol Commun ; 8(1): 182, 2020 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-33153497

RESUMEN

Recent discoveries have provided valuable insight into the genomic landscape of pediatric low-grade gliomas (LGGs) at diagnosis, facilitating molecularly targeted treatment. However, little is known about their temporal and therapy-related genomic heterogeneity. An adequate understanding of the evolution of pediatric LGGs' genomic profiles over time is critically important in guiding decisions about targeted therapeutics and diagnostic biopsy at recurrence. Fluorescence in situ hybridization, mutation-specific immunohistochemistry, and/or targeted sequencing were performed on paired tumor samples from primary diagnostic and subsequent surgeries. Ninety-four tumor samples from 45 patients (41 with two specimens, four with three specimens) from three institutions underwent testing. Conservation of BRAF fusion, BRAFV600E mutation, and FGFR1 rearrangement status was observed in 100%, 98%, and 96% of paired specimens, respectively. No loss or gain of IDH1 mutations or NTRK2, MYB, or MYBL1 rearrangements were detected over time. Histologic diagnosis remained the same in all tumors, with no acquired H3K27M mutations or malignant transformation. Changes in CDKN2A deletion status at recurrence occurred in 11 patients (42%), with acquisition of hemizygous CDKN2A deletion in seven and loss in four. Shorter time to progression and shorter time to subsequent surgery were observed among patients with acquired CDKN2A deletions compared to patients without acquisition of this alteration [median time to progression: 5.5 versus 16.0 months (p = 0.048); median time to next surgery: 17.0 months versus 29.0 months (p = 0.031)]. Most targetable genetic aberrations in pediatric LGGs, including BRAF alterations, are conserved at recurrence and following chemotherapy or irradiation. However, changes in CDKN2A deletion status over time were demonstrated. Acquisition of CDKN2A deletion may define a higher risk subgroup of pediatric LGGs with a poorer prognosis. Given the potential for targeted therapies for tumors harboring CDKN2A deletions, biopsy at recurrence may be indicated in certain patients, especially those with rapid progression.


Asunto(s)
Neoplasias Encefálicas/genética , Glioma/genética , Recurrencia Local de Neoplasia/genética , Adolescente , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/terapia , Niño , Preescolar , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Progresión de la Enfermedad , Femenino , Eliminación de Gen , Genoma , Genómica , Glioma/patología , Glioma/terapia , Humanos , Lactante , Isocitrato Deshidrogenasa/genética , Masculino , Glicoproteínas de Membrana/genética , Clasificación del Tumor , Recurrencia Local de Neoplasia/terapia , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas c-myb/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Receptor trkB/genética , Transactivadores/genética
3.
Sensors (Basel) ; 19(5)2019 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-30871016

RESUMEN

A robust 3-D GPR dataset provides interpreters with a variety of methods for extracting important information at buried archaeological sites. An iterative approach that uses reflection profile analysis, amplitude slice-mapping, and often both in conjunction is often necessary as neither method by itself is sufficient. In northern Australia, two constructed mounds contain a number of cultural and geological horizons and features, which can be imaged with GPR. The reflection profiles display the modified ground surface prior to mound construction and some initial construction layers. On the pre-mound surface, amplitude maps of reflective layers that were built-up on the ground surface indicate that they were constructed in an intentional manner. Those surfaces were later covered by sand to produce mounds used for human burial. Human internments in the mound can only be seen in reflection profiles, but once discovered, the profiles can be re-sliced to produce high definition amplitude images of these remains. No one method of analysis can provide an overall interpretation of these complex internal mound features. When the methods are varied, depending on the results of one method, a detailed and varied analysis of certain aspects of the mounds' internal features are visible, leading to the generation of a number of hypotheses about how this area of northern Australia was used in the past. The 3-D data from GPR shows that this area was an important location on the landscape in the past, and was modified by the construction of a monumental mound, which was then used for human burials, and more recently, the construction of what was likely a ritual enclosure.

4.
J Neurooncol ; 127(1): 53-61, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26626490

RESUMEN

Although bevacizumab has not proven effective in adults with newly diagnosed high-grade gliomas (HGG), feasibility in newly diagnosed children with diffuse intrinsic pontine gliomas (DIPG) or HGG has not been reported in a prospective study. In a safety and feasibility study, children and young adults with newly diagnosed HGG received radiotherapy (RT) with bevacizumab (10 mg/kg: days 22, 36) and temozolomide (75-90 mg/m(2)/day for 42 days) followed by bevacizumab (10 mg/kg, days 1, 15), irinotecan (125 mg/m(2), days 1, 15) and temozolomide (150 mg/m(2)/day days 1-5). DIPG patients did not receive temozolomide. Telomerase activity, quality of life (QOL), and functional outcomes were assessed. Among 27 eligible patients (15 DIPG, 12 HGG), median age 10 years (range 3-29 years), 6 discontinued therapy for toxicity: 2 during RT (grade 4 thrombocytopenia, grade 3 hepatotoxicity) and 4 during maintenance therapy (grade 3: thrombosis, hypertension, skin ulceration, and wound dehiscence). Commonest ≥grade 3 toxicities included lymphopenia, neutropenia and leukopenia. Grade 3 hypertension occurred in 2 patients. No intracranial hemorrhages occurred. For DIPG patients, median overall survival (OS) was 10.4 months. For HGG patients, 3-year progression free survival and OS were 33 % (SE ± 14 %) and 50 % (SE ± 14 %), respectively. All 3 tested tumor samples, demonstrated histone H3.3K27M (n = 2 DIPG) or G34R (n = 1 HGG) mutations. QOL scores improved over the course of therapy. A bevacizumab-based regimen is feasible and tolerable in newly diagnosed children and young adults with HGG and DIPG.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Tronco Encefálico/terapia , Quimioradioterapia , Glioma/terapia , Adolescente , Adulto , Bevacizumab/administración & dosificación , Neoplasias del Tronco Encefálico/diagnóstico , Camptotecina/administración & dosificación , Camptotecina/análogos & derivados , Niño , Preescolar , Dacarbazina/administración & dosificación , Dacarbazina/análogos & derivados , Femenino , Estudios de Seguimiento , Glioma/diagnóstico , Humanos , Irinotecán , Masculino , Clasificación del Tumor , Proyectos Piloto , Pronóstico , Tasa de Supervivencia , Temozolomida , Adulto Joven
5.
J Pediatr Hematol Oncol ; 37(4): e258-63, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25757023

RESUMEN

Chemotherapy is an essential component of therapy for infants and children with hepatoblastoma. Vincristine has been a mainstay of chemotherapeutic regimens used by North American cooperative groups, based on indirect evidence of benefit and an assumption of minimal added toxicity. European cooperative group trials have reported comparable survival rates using regimens that omit vincristine. Further examination of the risk and benefit profile of vincristine relevant to hepatoblastoma clinical care paradigms is thus warranted. We evaluated the incidence of vincristine-related sensorimotor peripheral, autonomic, and cranial nerve neurological morbidities in 45 consecutive hepatoblastoma patients treated at our institution. Data suggest an increased risk of vincristine-associated neuropathic grade 2 and 3 events (neuropathic pain and gross motor impairment) in children ages 24 months old or younger, and particularly in children born prematurely. Formal prospective investigation of the relative risks and benefits of vincristine in hepatoblastoma treatment is warranted to assess the value of continued use of vincristine in this patient population.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Hepatoblastoma/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Síndromes de Neurotoxicidad/etiología , Vincristina/efectos adversos , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Morbilidad
6.
J Neurooncol ; 122(1): 169-77, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25582835

RESUMEN

Pediatric tectal plate gliomas are indolent slow-growing gliomas that often present with increased intracranial pressure or incidentally on routine brain imaging. We investigated clinical outcomes, endocrinopathies, and neuropsychological sequelae associated with tectal plate gliomas. Twenty-six patients with tectal plate glioma were identified in a 20-year retrospective review. Clinical outcomes, treatments, endocrine function, neuropsychological testing outcomes and radiographic imaging were reviewed for possible signs correlating with tumor progression. Among 26 patients, 19 presented with signs or symptoms of increased intracranial pressure (73 %) versus an incidental finding in 7 (27 %). Median follow-up was 46 months (range 8-143 months). Six of 26 (23 %) experienced progressive disease after diagnosis. Five of 26 (19 %) required more than one surgical procedure due to failure of initial endoscopic third ventriculostomy. Seven of 26 had history of endocrine dysfunction, of which, five presented with endocrine dysfunction (precocious puberty or short stature), 1 developed menstrual irregularities after surgical intervention and 1 had preexisting pan hypopituitarism. Of 12 patients with available neuropsychological testing, eleven had at least one indicator of executive functioning in the low-average to impaired range. While tectal plate gliomas have been considered indolent tumors that are rarely progressive, 23 % of patients in our cohort experienced disease progression and required further therapy. Neurocognitive deficits may occur, while endocrine deficiency is uncommon. Regular multidisciplinary oncology follow-up, routine monitoring with MRI and formal neurocognitive evaluation are imperative to provide early recognition of disease progression or recurrent hydrocephalus and to improve school functioning in this population.


Asunto(s)
Neoplasias del Tronco Encefálico/complicaciones , Enfermedades del Sistema Endocrino/etiología , Glioma/complicaciones , Procedimientos Neuroquirúrgicos/efectos adversos , Techo del Mesencéfalo/patología , Adolescente , Neoplasias del Tronco Encefálico/patología , Neoplasias del Tronco Encefálico/psicología , Neoplasias del Tronco Encefálico/cirugía , Niño , Preescolar , Progresión de la Enfermedad , Enfermedades del Sistema Endocrino/diagnóstico , Enfermedades del Sistema Endocrino/psicología , Femenino , Estudios de Seguimiento , Glioma/patología , Glioma/psicología , Humanos , Lactante , Masculino , Estadificación de Neoplasias , Pruebas Neuropsicológicas , Pronóstico , Estudios Retrospectivos , Techo del Mesencéfalo/cirugía
7.
J Neurooncol ; 121(3): 591-8, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25433556

RESUMEN

There is a paucity of data regarding patterns of progression in children with high-grade glioma (HGG) or diffuse intrinsic pontine glioma (DIPG) treated with bevacizumab (BVZ) at diagnosis. We performed a retrospective study of 20 children with HGG or DIPG who received BVZ-based therapy at diagnosis on, or according to, a bi-institutional study. Magnetic resonance imaging (MRI) characteristics of first and most recent progressions were reviewed. Comparison was made to a control group of 19 patients who never received BVZ. Imaging definitions of progressive disease (PD) were local: at primary site or within 2 cm, contiguous; diffuse: >2 cm away but contiguous with primary site, ill-defined and infiltrative; distant: new, non-contiguous disease. In the BVZ-treated group, 14 patients had DIPG, six patients had HGG. Median age was 7 years (range: 3-21). Median time to PD and follow-up were 8.8 months (range 4-21) and 11 months (range: 6-25), respectively. Among 14 patients with PD, 8 (57.1 %) had local PD, 6 (42.9 %) had local and diffuse/distant PD, at initial progression. At most recent progression, a median of 10.8 months (range 6-25) from diagnosis, 10 of 14 (71.4 %) had at least diffuse (n = 8), or distant (n = 6) PD. In the comparable control group, 15 patients had PD: 11(73.3 %) local, 4 (26.7 %) local and diffuse/distant PD at first and most recent progressions. Based on these data, we postulate that BVZ may lead to a higher incidence of distant and diffuse disease in newly-diagnosed children with HGG or DIPG who received BVZ-based therapy.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Antineoplásicos/administración & dosificación , Neoplasias Encefálicas/patología , Glioma/patología , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Bevacizumab , Neoplasias Encefálicas/tratamiento farmacológico , Camptotecina/administración & dosificación , Camptotecina/análogos & derivados , Quimioradioterapia , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Glioma/tratamiento farmacológico , Humanos , Irinotecán , Masculino , Clasificación del Tumor , Estudios Retrospectivos , Adulto Joven
8.
Childs Nerv Syst ; 30(8): 1383-91, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24770664

RESUMEN

OBJECTIVE: Children suffering from epilepsy with suspected low-grade tumors may benefit from a surgical approach that considers the epileptogenic zone, which can be more extensive than the tumor region. This study aimed to determine the prevalence of epilepsy in children undergoing supratentorial tumor resection and the factors predictive of postoperative seizure freedom in children with low-grade tumors. METHODS: Subjects 3 months to 21 years undergoing supratentorial brain tumor resection between 2007 and 2011 were included in this retrospective study. Children with supratentorial, cortically based tumors and a preoperative diagnosis of epilepsy were considered epilepsy surgery candidates. Pre- and postoperative MRI were reviewed and scored for extent of resection, adjacent dysplasia, and remaining abnormal cortex postoperatively. RESULTS: The prevalence of seizures in all cases of supratentorial tumors was 46/87 (53 %). Eighteen were epilepsy surgery candidates. Eight of 18 (44 %) were seizure-free postoperatively with a mean follow-up of 39 months. Children who were seizure free postoperatively had tried fewer anticonvulsants than those with continued seizures (1.7 v. 2.9, p = 0.01). Presurgical evaluation was nonstandardized, and a more extensive workup and resection were performed in children who continued to have seizures postoperatively. CONCLUSIONS: All epilepsy surgery candidates had low-grade tumors on histological evaluation, indicating that a surgical approach that takes into consideration the epileptogenic zone is reasonable in this population. Gross total resection should be the goal, with additional attention to resection of the epileptogenic zone when located in the noneloquent cortex.


Asunto(s)
Epilepsia/epidemiología , Epilepsia/cirugía , Procedimientos Neuroquirúrgicos/efectos adversos , Adolescente , Niño , Preescolar , Electroencefalografía , Epilepsia/etiología , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos , Neoplasias Supratentoriales/complicaciones , Neoplasias Supratentoriales/cirugía , Adulto Joven
9.
J Neurooncol ; 103(3): 759-64, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20953660

RESUMEN

Medulloblastoma with melanotic differentiation, a rare variant of medulloblastoma, often carries a poor prognosis. We present such a case of a 4 year male with this rare, aggressive tumor. Additionally, we have reviewed the literature and report on the features important in the pathologic and radiologic diagnosis in this type of tumor, as well as review clinical outcomes. This subtype of medulloblastoma occurs more frequently in males, at a younger median age than the other subtypes of medulloblastoma. The prognosis is generally very poor. However, it is important to note, that a subset of patients with M0 disease who can achieve a gross total resection followed by radiation and platinum based chemotherapy can become long term survivors of this aggressive subtype of medulloblastoma.


Asunto(s)
Neoplasias Cerebelosas/diagnóstico , Meduloblastoma/diagnóstico , Neoplasias Cerebelosas/terapia , Preescolar , Humanos , Antígeno Ki-67 , Imagen por Resonancia Magnética , Masculino , Meduloblastoma/terapia , Mucina-1/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Radioterapia , Tomografía Computarizada por Rayos X
10.
J Food Prot ; 71(11): 2307-11, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19044278

RESUMEN

A method is described for the identification of dorsal root ganglia (DRG)-associated sensory neurons within advanced meat recovery (AMR) product derived from bovine vertebral columns. This method relies on the unique microanatomy of sensory neurons and immunohistochemical staining, primarily for glial fibrillary acidic protein. Sensory neurons are variably sized unipolar neurons, exhibiting a single-cell process that is rarely seen in histologic sections. These neurons are surrounded by a prominent ring of glial fibrillary acidic protein-positive satellite cells that produce a distinctive and readily identifiable staining pattern in histologic sections. Fragmented DRG were detected to the 0.25% level in samples of ground beef or nonvertebral-origin AMR product spiked with these sensory ganglia. Similarly examined commercially produced nonvertebral-origin AMR product (n = 157) did not contain sensory ganglia, while 3.3% of vertebral-origin AMR product (n = 364) contained fragmented DRG.


Asunto(s)
Contaminación de Alimentos/análisis , Ganglios Espinales/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Carne/análisis , Animales , Bovinos , Seguridad de Productos para el Consumidor , Estudios de Evaluación como Asunto , Humanos , Inmunohistoquímica/métodos , Productos de la Carne/análisis , Reproducibilidad de los Resultados , Células Satélites Perineuronales , Sensibilidad y Especificidad , Células Receptoras Sensoriales
12.
J Transl Med ; 3(1): 9, 2005 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-15723705

RESUMEN

BACKGROUND: There is a continued need to develop more effective cancer immunotherapy strategies. Exosomes, cell-derived lipid vesicles that express high levels of a narrow spectrum of cell proteins represent a novel platform for delivering high levels of antigen in conjunction with costimulatory molecules. We performed this study to test the safety, feasibility and efficacy of autologous dendritic cell (DC)-derived exosomes (DEX) loaded with the MAGE tumor antigens in patients with non-small cell lung cancer (NSCLC). METHODS: This Phase I study enrolled HLA A2+ patients with pre-treated Stage IIIb (N = 4) and IV (N = 9) NSCLC with tumor expression of MAGE-A3 or A4. Patients underwent leukapheresis to generate DC from which DEX were produced and loaded with MAGE-A3, -A4, -A10, and MAGE-3DPO4 peptides. Patients received 4 doses of DEX at weekly intervals. RESULTS: Thirteen patients were enrolled and 9 completed therapy. Three formulations of DEX were evaluated; all were well tolerated with only grade 1-2 adverse events related to the use of DEX (injection site reactions (N = 8), flu like illness (N = 1), and peripheral arm pain (N = 1)). The time from the first dose of DEX until disease progression was 30 to 429+ days. Three patients had disease progression before the first DEX dose. Survival of patients after the first DEX dose was 52-665+ days. DTH reactivity against MAGE peptides was detected in 3/9 patients. Immune responses were detected in patients as follows: MAGE-specific T cell responses in 1/3, increased NK lytic activity in 2/4. CONCLUSION: Production of the DEX vaccine was feasible and DEX therapy was well tolerated in patients with advanced NSCLC. Some patients experienced long term stability of disease and activation of immune effectors.

13.
J Acquir Immune Defic Syndr ; 30(4): 392-400, 2002 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12138345

RESUMEN

Valganciclovir, an oral prodrug of the anti-cytomegalovirus (CMV) agent ganciclovir, was evaluated in a single-arm open-label safety study. AIDS patients (median CD4 lymphocyte count of 140 cells/microL) with treated CMV retinitis (N = 212) received 900-mg once-daily valganciclovir maintenance therapy with courses of 900-mg twice-daily valganciclovir induction therapy as needed to treat progression. After a median treatment duration of 372 days, the adverse event profile was similar to that reported for intravenous (IV) and oral ganciclovir. Adverse event rates of note were diarrhea (35%), nausea (23%), fever (18%), neutropenia (absolute neutrophil count <500 cells/microL) (10%), and anemia (hemoglobin <8.0 g/dL) (12%). Consistent with prior treatment studies of oral ganciclovir, IV catheter-related adverse events were uncommon (6%) and lower than previously reported for IV ganciclovir. The mortality rate was 0.072 deaths per patient-year. Progression of CMV retinitis occurred in 17% of patients during the study treatment period, usually in association with a low CD4 cell count. Other than a higher than expected frequency of oral candidiasis (17%), no clinical toxicities or laboratory abnormalities occurred during treatment with valganciclovir that have not been observed during treatment with ganciclovir.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Antivirales/administración & dosificación , Antivirales/efectos adversos , Retinitis por Citomegalovirus/tratamiento farmacológico , Ganciclovir/análogos & derivados , Ganciclovir/administración & dosificación , Ganciclovir/efectos adversos , Administración Oral , Adulto , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Candidiasis Bucal/etiología , Retinitis por Citomegalovirus/complicaciones , Tolerancia a Medicamentos , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Humanos , Masculino , Persona de Mediana Edad , Profármacos/administración & dosificación , Profármacos/efectos adversos , Seguridad , Valganciclovir
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