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1.
BMC Cancer ; 24(1): 332, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38475765

RESUMEN

BACKGROUND AND OBJECTIVES: Almost one third of cancer patients in the United States will develop brain metastases on an annual basis. Surgical resection is indicated in the setting of brain metastases for reasons, such as maximizing local control in select patients, decompression of mass effect, and/or tissue diagnosis. The current standard of care following resection of a brain metastasis has shifted from whole brain radiation therapy to post-operative stereotactic radiosurgery (SRS). However, there is a significant rate of local recurrence within one year of postoperative SRS. Emerging retrospective and prospective data suggest pre-operative SRS is a safe and potentially effective treatment paradigm for surgical brain metastases. This trial intends to determine, for patients with an indication for resection of a brain metastasis, whether there is an increase in the time to a composite endpoint of adverse outcomes; including the first occurrence of either: local recurrence, leptomeningeal disease, or symptomatic radiation brain necrosis - in patients who receive pre-operative SRS as compared to patients who receive post-operative SRS. METHODS: This randomized phase III clinical trial compares pre-operative with post-operative SRS for brain metastases. A dynamic random allocation procedure will allocate an equal number of patients to each arm: pre-operative SRS followed by surgery or surgery followed by post-operative SRS. EXPECTED OUTCOMES: If pre-operative SRS improves outcomes relative to post-operative SRS, this will establish pre-operative SRS as superior. If post-operative SRS proves superior to pre-operative SRS, it will remain a standard of care and halt the increasing utilization of pre-operative SRS. If there is no difference in pre- versus post-operative SRS, then pre-operative SRS may still be preferred, given patient convenience and the potential for a condensed timeline. DISCUSSION: Emerging retrospective and prospective data have demonstrated some benefits of pre-op SRS vs. post-op SRS. This study will show whether there is an increase in the time to the composite endpoint. Additionally, the study will compare overall survival; patient-reported outcomes; morbidity; completion of planned therapies; time to systemic therapy; time to regional progression; time to CNS progression; time to subsequent treatment; rate of radiation necrosis; rate of local recurrence; and rate of leptomeningeal disease. TRIAL REGISTRATION NUMBER: NCT03750227 (Registration date: 21/11/2018).


Asunto(s)
Neoplasias Encefálicas , Radiocirugia , Humanos , Estudios Retrospectivos , Radiocirugia/métodos , Estudios Prospectivos , Resultado del Tratamiento , Neoplasias Encefálicas/secundario , Necrosis/etiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Ensayos Clínicos Fase III como Asunto
2.
PLoS Comput Biol ; 19(2): e1010914, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36848379

RESUMEN

Environmentally induced or epigenetic-related beta-cell dysfunction and insulin resistance play a critical role in the progression to diabetes. We developed a mathematical modeling framework capable of studying the progression to diabetes incorporating various diabetogenic factors. Considering the heightened risk of beta-cell defects induced by obesity, we focused on the obesity-diabetes model to further investigate the influence of obesity on beta-cell function and glucose regulation. The model characterizes individualized glucose and insulin dynamics over the span of a lifetime. We then fit the model to the longitudinal data of the Pima Indian population, which captures both the fluctuations and long-term trends of glucose levels. As predicted, controlling or eradicating the obesity-related factor can alleviate, postpone, or even reverse diabetes. Furthermore, our results reveal that distinct abnormalities of beta-cell function and levels of insulin resistance among individuals contribute to different risks of diabetes. This study may encourage precise interventions to prevent diabetes and facilitate individualized patient treatment.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Resistencia a la Insulina/fisiología , Insulina , Obesidad/complicaciones , Glucosa , Glucemia
3.
Diabetes Obes Metab ; 26(2): 463-472, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37867175

RESUMEN

AIM: This study compared the 5-year incidence rate of macrovascular and microvascular complications for tirzepatide, semaglutide and insulin glargine in individuals with type 2 diabetes, using the Building, Relating, Assessing, and Validating Outcomes (BRAVO) diabetes simulation model. RESEARCH DESIGN AND METHODS: This study was a 5-year SURPASS-2 trial extrapolation, with an insulin glargine arm added as an additional comparator. The 1-year treatment effects of tirzepatide (5, 10 or 15 mg), semaglutide (1 mg) and insulin glargine on glycated haemoglobin, systolic blood pressure, low-density lipoprotein and body weights were obtained from the SUSTAIN-4 and SURPASS-2 trials. We used the BRAVO model to predict 5-year complications for each study arm under two scenarios: the 1-year treatment effects persisted (optimistic) or diminished to none in 5 years (conservative). RESULTS: When compared with insulin glargine, we projected a 5-year risk reduction in cardiovascular adverse events [rate ratio (RR) 0.64, 95% confidence interval (CI) 0.61-0.67] and microvascular composite (RR 0.67, 95% CI 0.64-0.70) with 15 mg tirzepatide, and 5-year risk reduction in cardiovascular adverse events (RR 0.75, 95% CI 0.72-0.79) and microvascular composite (RR 0.79, 95% CI 0.76-0.82) with semaglutide (1 mg) under an optimistic scenario. Lower doses of tirzepatide also had similar, albeit smaller benefits. Treatment effects for tirzepatide and semaglutide were smaller but still significantly higher than insulin glargine under a conservative scenario. The 5-year risk reduction in diabetes-related complication events and mortality for the 15 mg tirzepatide compared with insulin glargine ranged from 49% to 10% under an optimistic scenario, which was reduced by 17%-33% when a conservative scenario was assumed. CONCLUSION: With the use of the BRAVO diabetes model, tirzepatide and semaglutide exhibited potential to reduce the risk of macrovascular and microvascular complications among individuals with type 2 diabetes, compared with insulin glargine in a 5-year window. Based on the current modelling assumptions, tirzepatide (15 mg) may potentially outperform semaglutide (1 mg). While the BRAVO model offered insights, the long-term cardiovascular benefit of tirzepatide should be further validated in a prospective clinical trial.


Asunto(s)
Complicaciones de la Diabetes , Diabetes Mellitus Tipo 2 , Humanos , Complicaciones de la Diabetes/tratamiento farmacológico , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/efectos adversos , Insulina Glargina/efectos adversos , Estudios Prospectivos
4.
Clin Auton Res ; 34(2): 233-252, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38709357

RESUMEN

PURPOSE: We conducted a meta-analysis to determine the effect of hyperoxia on muscle sympathetic nerve activity in healthy individuals and those with cardio-metabolic diseases. METHODS: A comprehensive search of electronic databases was performed until August 2022. All study designs (except reviews) were included: population (humans; apparently healthy or with at least one chronic disease); exposures (muscle sympathetic nerve activity during hyperoxia or hyperbaria); comparators (hyperoxia or hyperbaria vs. normoxia); and outcomes (muscle sympathetic nerve activity, heart rate, blood pressure, minute ventilation). Forty-nine studies were ultimately included in the meta-analysis. RESULTS: In healthy individuals, hyperoxia had no effect on sympathetic burst frequency (mean difference [MD] - 1.07 bursts/min; 95% confidence interval [CI] - 2.17, 0.04bursts/min; P = 0.06), burst incidence (MD 0.27 bursts/100 heartbeats [hb]; 95% CI - 2.10, 2.64 bursts/100 hb; P = 0.82), burst amplitude (P = 0.85), or total activity (P = 0.31). In those with chronic diseases, hyperoxia decreased burst frequency (MD - 5.57 bursts/min; 95% CI - 7.48, - 3.67 bursts/min; P < 0.001) and burst incidence (MD - 4.44 bursts/100 hb; 95% CI - 7.94, - 0.94 bursts/100 hb; P = 0.01), but had no effect on burst amplitude (P = 0.36) or total activity (P = 0.90). Our meta-regression analyses identified an inverse relationship between normoxic burst frequency and change in burst frequency with hyperoxia. In both groups, hyperoxia decreased heart rate but had no effect on any measure of blood pressure. CONCLUSION: Hyperoxia does not change sympathetic activity in healthy humans. Conversely, in those with chronic diseases, hyperoxia decreases sympathetic activity. Regardless of disease status, resting sympathetic burst frequency predicts the degree of change in burst frequency, with larger decreases for those with higher resting activity.


Asunto(s)
Hiperoxia , Músculo Esquelético , Sistema Nervioso Simpático , Humanos , Hiperoxia/fisiopatología , Sistema Nervioso Simpático/fisiología , Sistema Nervioso Simpático/fisiopatología , Músculo Esquelético/fisiología , Músculo Esquelético/inervación , Frecuencia Cardíaca/fisiología
5.
Neuropathology ; 44(4): 278-284, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38129983

RESUMEN

Astroblastoma, MN1-altered, is a rare neoplasm of the central nervous system (CNS). This malignancy shares similar histopathological features with other CNS tumors, including ependymomas, making it challenging to diagnose. DNA methylation profiling is a new and robust technique that may be used to overcome this diagnostic hurdle. We report the case of a now 25-year-old female diagnosed with what was initially called an ependymoma located in the cervical spine at the age of 2 years old. After initial resection, the tumor recurred multiple times and within 2 years of diagnosis had disseminated disease throughout the brain and spinal cord. She has now undergone over two decades of treatment, including multiple surgical resections, radiation therapy, and administration of numerous chemotherapeutic agents. In 2021, the patient presented to our institution with lumbosacral radicular symptoms due to enlarging lesions within the lumbosacral spine. Reexamination of formalin-fixed, paraffin-embedded material from the patient's tumor using genomic DNA methylation profiling resulted in a diagnostic change from grade III anaplastic ependymoma to astroblastoma, MN1-altered. This work describes another confirmed case of astroblastoma, MN1-altered, to the growing body of literature.


Asunto(s)
Neoplasias Neuroepiteliales , Neoplasias de la Médula Espinal , Humanos , Femenino , Neoplasias Neuroepiteliales/genética , Neoplasias Neuroepiteliales/patología , Neoplasias Neuroepiteliales/diagnóstico por imagen , Adulto , Neoplasias de la Médula Espinal/genética , Neoplasias de la Médula Espinal/patología , Neoplasias de la Médula Espinal/diagnóstico por imagen , Factores de Transcripción/genética , Proteínas de Fusión Oncogénica/genética , Transactivadores , Proteínas Supresoras de Tumor
6.
Can J Neurol Sci ; 50(1): 1-9, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-34711299

RESUMEN

The surgical treatment of insular gliomas requires specialized knowledge. Over the last three decades, increased momentum in surgical resection of insular gliomas shifted the focus from one of expectant management to maximal safe resection to establish a diagnosis, characterize tumor genetics, treat preoperative symptoms (i.e., seizures), and delay malignant transformation through tumor cytoreduction. A comprehensive review of the literature was performed regarding insular glioma classification/genetics, insular anatomy, surgical approaches, and patient outcomes. Modern large, published series of insular resections have reported a median 80% resection, 80% improvement in preoperative seizures, and postsurgical permanent neurologic deficits of less than 10%. Major complication avoidance includes recognition and preservation of eloquent cortex for language and respecting the lateral lenticulostriate arteries.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Neoplasias Encefálicas/complicaciones , Resultado del Tratamiento , Imagen por Resonancia Magnética , Glioma/patología , Procedimientos Neuroquirúrgicos/efectos adversos , Convulsiones/etiología , Corteza Cerebral/patología
7.
Neurosurg Focus ; 55(2): E17, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37527680

RESUMEN

OBJECTIVE: The objective of this review was to describe the immunological changes that take place in the dura mater in response to metastatic disease that seeds the CNS. The authors hypothesized that the dura's anatomy and resident immune cell population play a role in enabling metastasis to the brain and leptomeninges. METHODS: An extensive literature search was conducted to identify evidence that supports the dura's participation in metastasis to the CNS. The authors' hypothesis was informed by a recent upsurge in studies that have investigated the dura's role in metastatic development, CNS infections, and autoimmunity. They reviewed this literature as well as the use of immunotherapy in treating brain metastases and how these therapies change the meningeal immune landscape to overcome and reverse tumor-promoting immunosuppression. RESULTS: Evidence suggests that the unique architecture and immune cell profile of the dura, compared with other immune compartments within the CNS, facilitate entry of metastatic tumor cells into the brain. Once these tumor cells penetrate the dural barrier, they propagate an immunosuppressive tumor microenvironment. Therefore, immunotherapy may serve to overcome this immunosuppressive environment and liberate proinflammatory immune cells in an effort to combat metastatic disease. CONCLUSIONS: Within the next few years, the authors expect the addition of several more scientific studies into the literature that further underscore the dura as a chief participant and neuroanatomical barrier in neuro-oncology.


Asunto(s)
Neoplasias Encefálicas , Neoplasias Supratentoriales , Humanos , Duramadre/patología , Neoplasias Encefálicas/patología , Encéfalo , Microambiente Tumoral
8.
Neurosurg Focus ; 54(4): E6, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37004136

RESUMEN

OBJECTIVE: Idiopathic normal pressure hydrocephalus (iNPH) results in significant morbidity in the elderly with symptoms of dementia, gait instability, and urinary incontinence. In well-selected patients, ventriculoperitoneal shunt (VPS) placement often results in clinical improvement. Most postshunt assessments of patients rely on subjective scales. The goal of this study was to assess the utility of remote activity monitoring to provide objective evidence of gait improvement following VPS placement for iNPH. METHODS: Patients with iNPH were prospectively enrolled and fitted with 5 activity monitors (on the hip and bilateral thighs and ankles) that they wore for 4 days preoperatively within 30 days of surgery and for 4 days within 30 days postoperatively. Monitors collected continuous data for number of steps, cadence, body position (upright, prone, supine, and lateral decubitus), gait entropy, and the proportion of each day spent active or static. Data were retrieved from the devices and a comparison of pre- and postoperative movement assessment was performed. The gait data were also correlated with formal clinical gait assessments before and after lumbar puncture and with motion analysis laboratory testing at baseline and 1 month and 1 year after VPS placement. RESULTS: Twenty patients fulfilled the inclusion and exclusion criteria (median age 76 years). The baseline median number of daily steps was 1929, the median percentage of the day spent inactive was 70%, the median percentage of the day with a static posture was 95%, the median gait velocity was 0.49 m/sec, and the median number of steps required to turn was 8. There was objective improvement in median entropy from pre- to postoperatively, increasing from 0.6 to 0.8 (p = 0.002). There were no statistically significant differences for any of the remaining variables measured by the activity monitors when comparing the preoperative to the 1-month postoperative time point. All variables from motion analysis testing showed statistically significant differences or a trend toward significance at 1 year after VPS placement. Among the significantly correlated variables at baseline, cadence was inversely correlated with percentage of gait cycle spent in the support phase (contact with ground vs swing phase). CONCLUSIONS: This pilot study suggests that activity monitoring provides an early objective measure of improvement in gait entropy after VPS placement among patients with iNPH, although a more significant improvement was noted on the detailed clinical gait assessments. Further long-term studies are needed to determine the utility of remote monitoring for assessing gait improvement following VPS placement.


Asunto(s)
Hidrocéfalo Normotenso , Derivación Ventriculoperitoneal , Humanos , Anciano , Derivación Ventriculoperitoneal/métodos , Hidrocéfalo Normotenso/cirugía , Hidrocéfalo Normotenso/diagnóstico , Proyectos Piloto , Resultado del Tratamiento , Estudios Longitudinales
9.
Int J Mol Sci ; 24(8)2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-37108470

RESUMEN

Sudden sensorineural hearing loss (SSNHL) is an acquired idiopathic hearing loss. Serum levels of small, non-coding RNAs and microRNAs (miRNAs) miR-195-5p/-132-3p/-30a-3p/-128-3p/-140-3p/-186-5p/-375-3p/-590-5p are differentially expressed in SSNHL patients within 28 days of hearing loss onset. This study determines if these changes persist by comparing the serum miRNA expression profile of SSNHL patients within 1 month of hearing loss onset with that of patients 3-12 months after hearing loss onset. We collected serum from consenting adult SSNHL patients at presentation or during clinic follow-up. We matched patient samples drawn 3-12 months after hearing loss onset (delayed group, n = 9 patients) by age and sex to samples drawn from patients within 28 days of hearing loss onset (immediate group, n = 14 patients). We compared the real-time PCR-determined expression levels of the target miRNAs between the two groups. We calculated the air conduction pure-tone-averaged (PTA) audiometric thresholds in affected ears at the initial and final follow-up visits. We undertook inter-group comparisons of hearing outcome status and initial and final PTA audiometric thresholds. There was no significant inter-group difference in miRNA expression level, hearing recovery status and initial and final affected ear PTA audiometric thresholds.


Asunto(s)
Sordera , Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , MicroARNs , Adulto , Humanos , MicroARNs/genética , Pérdida Auditiva Sensorineural/genética , Pérdida Auditiva Súbita/genética , Audición/genética , Estudios Retrospectivos
10.
J Environ Manage ; 345: 118636, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37574637

RESUMEN

To effectively manage species and habitats at multiple scales, population and land managers require rapid information on wildlife use of managed areas and responses to landscape conditions and management actions. GPS tracking studies of wildlife are particularly informative to species ecology, habitat use, and conservation. Combining GPS data with administrative data and a diverse suite of remotely sensed, geo-referenced environmental (e.g., climatic) data, would more comprehensively inform how animals interact with and utilize habitats and ecosystems and our goal was to create a conceptual model for a system that would accomplish this - the 'Automated Interactive Monitoring System (AIMS) for Wildlife'. Our objective for this study was to develop a Customized Wildlife Report (CWR) - the first AIMS for Wildlife deliverable product. CWRs collate and summarize our 8-year GPS tracking dataset of ∼11 million locations from 1338 individual (16 species) avifauna and make actionable, real-time data on animal movements and trends in a specific area of interest available to managers and stakeholders for rapid application in day-to-day management. The CWR exemplar presented in this paper was developed to address needs identified by habitat managers of Sacramento National Wildlife Refuge and illustrates the highly specific, information offered and how it contributes to assessing the efficacy of conservation actions while allowing for near real-time adaptive management. The report can be easily customized for any of the thousands of wildlife refuges or regional areas of interest in the United States, emphasizing the broad application of an animal movement data stream. Utilizing diverse, extensive telemetry data streams through scientific collaboration can aid managers and conservation stakeholders with short and long-term research and conservation planning and help address a cadre of issues from local-scale habitat management to improving the understanding of landscape level impacts like drought, wildfire, and climate change on wildlife populations.


Asunto(s)
Animales Salvajes , Ecosistema , Animales , Estados Unidos , Ecología , Modelos Teóricos , Telemetría , Conservación de los Recursos Naturales
11.
Am J Pathol ; 191(3): 454-462, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33307036

RESUMEN

Emerging data suggest that type 1 diabetes affects not only the ß-cell-containing islets of Langerhans, but also the surrounding exocrine compartment. Using digital pathology, machine learning algorithms were applied to high-resolution, whole-slide images of human pancreata to determine whether the tissue composition in individuals with or at risk for type 1 diabetes differs from those without diabetes. Transplant-grade pancreata from organ donors were evaluated from 16 nondiabetic autoantibody-negative controls, 8 nondiabetic autoantibody-positive subjects with increased type 1 diabetes risk, and 19 persons with type 1 diabetes (0 to 12 years' duration). HALO image analysis algorithms were implemented to compare architecture of the main pancreatic duct as well as cell size, density, and area of acinar, endocrine, ductal, and other nonendocrine, nonexocrine tissues. Type 1 diabetes was found to affect exocrine area, acinar cell density, and size, whereas the type of difference correlated with the presence or absence of insulin-positive cells remaining in the pancreas. These changes were not observed before disease onset, as indicated by modeling cross-sectional data from pancreata of autoantibody-positive subjects and those diagnosed with type 1 diabetes. These data provide novel insights into anatomic differences in type 1 diabetes pancreata and demonstrate that machine learning can be adapted for the evaluation of disease processes from cross-sectional data sets.


Asunto(s)
Algoritmos , Autoanticuerpos/inmunología , Diabetes Mellitus Tipo 1/patología , Procesamiento de Imagen Asistido por Computador/métodos , Aprendizaje Automático , Páncreas/patología , Adolescente , Autoanticuerpos/sangre , Estudios de Casos y Controles , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/metabolismo , Femenino , Humanos , Insulina/análisis , Páncreas/inmunología , Páncreas/metabolismo , Donantes de Tejidos
12.
J Neurooncol ; 159(2): 221-231, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35902552

RESUMEN

OBJECT: Hemangioblastoma is a relatively rare neoplasm occurring mostly in the cerebellum that may arise sporadically or in the context of von Hippel-Lindau (VHL) syndrome. Presentation, imaging, natural history, surgical patterns of care, and outcomes are incompletely defined for this uncommon lesion. We reviewed our large institutional series to help clarify these issues. METHODS: Retrospective analysis of consecutive, neurosurgically managed CNS hemangioblastomas at Mayo Clinic, 1988-2018. RESULTS: Two hundred and eighty five hemangioblastomas were treated in 184 unique patients (115 sporadic, 69 VHL). Compared to sporadic patients, VHL patients were younger (36.7 vs 51.7 years; p < 0.0001), were treated while asymptomatic more commonly (47.3 vs 4.2%; p < 0.0001), had smaller lesions (6.6 vs 13.9 mL; p < 0.0001), and harbored lesions with associated cysts less frequently (51.0 vs 75.0%; p = 0.0002). Macrocystic tumor architecture was associated with larger lesion size and greater symptom severity. Solid lesions later formed cysts at a median 130 months. Growth in both total volume and solid component accelerated after cyst formation (10.6 and 6.0 times median rate prior to cyst emergence). VHL patients died at a younger age (47.9 vs 74.5, p = 0.0017) and were more likely to die of direct disease sequelae. Though treatment-free survival time was significantly longer in sporadic cases, a substantial fraction (> 40%) developed tumor recurrence/progression requiring additional treatment. CONCLUSIONS: Hemangioblastoma presentation varies with etiology and clinical course is more complicated in VHL cases. Nodular lesions often develop cysts over time which is associated with accelerated tumor growth. Sporadic cases have a previously unappreciated but substantial risk of late recurrence/progression requiring treatment.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Quistes , Hemangioblastoma , Enfermedad de von Hippel-Lindau , Cerebelo , Humanos , Estudios Retrospectivos
13.
Neurosurg Focus ; 52(2): E5, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35104794

RESUMEN

Glioblastoma is the most common primary malignant brain neoplasm with dismal 10-year survival rates of < 1%. Despite promising preliminary results from several novel therapeutic agents, clinical responses have been modest due to several factors, including tumor heterogeneity, immunosuppressive tumor microenvironment, and treatment resistance. Novel immunotherapeutics have been developed to reverse tumor-induced immunosuppression in patients with glioblastomas. In order to recapitulate the tumor microenvironment, reliable in vivo syngeneic murine models are critical for the development of new targeted agents as these models demonstrate rapid tumor induction and reliable tumor growth over multiple generations. Despite the clear advantages of murine models, choosing an appropriate model from an immunological perspective can be difficult and have significant ramifications on the translatability of the results from murine to human trials. Herein, the authors reviewed the 4 most commonly used immunocompetent syngeneic murine glioma models (GL261 [C57BL/6], SB28 [C57BL/6], CT-2A [C57BL/6], and SMA-560 [VM/Dk]) and compared their strengths and weaknesses from an immunological standpoint.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glioma , Animales , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Glioma/patología , Humanos , Inmunoterapia , Ratones , Ratones Endogámicos C57BL , Microambiente Tumoral
14.
Diabetologia ; 64(4): 836-844, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33496819

RESUMEN

AIMS/HYPOTHESIS: We aimed to compare characteristics of individuals identified in the peri-diagnostic range by Index60 (composite glucose and C-peptide measure) ≥2.00, 2 h OGTT glucose ≥11.1 mmol/l, or both. METHODS: We studied autoantibody-positive participants in the Type 1 Diabetes TrialNet Pathway to Prevention study who, at their baseline OGTT, had 2 h blood glucose ≥11.1 mmol/l and/or Index60 ≥2.00 (n = 354, median age = 11.2 years, age range = 1.7-46.6; 49% male, 83% non-Hispanic White). Type 1 diabetes-relevant characteristics (e.g., age, C-peptide, autoantibodies, BMI) were compared among three mutually exclusive groups: 2 h glucose ≥11.1 mmol/l and Index60 <2.00 [Glu(+), n = 76], 2 h glucose <11.1 mmol/l and Index60 ≥2.00 [Ind(+), n = 113], or both 2 h glucose ≥11.1 mmol/l and Index60 ≥2.00 [Glu(+)/Ind(+), n = 165]. RESULTS: Participants in Glu(+), vs those in Ind(+) or Glu(+)/Ind(+), were older (mean ages = 22.9, 11.8 and 14.7 years, respectively), had higher early (30-0 min) C-peptide response (1.0, 0.50 and 0.43 nmol/l), higher AUC C-peptide (2.33, 1.13 and 1.10 nmol/l), higher percentage of overweight/obesity (58%, 16% and 30%) (all comparisons, p < 0.0001), and a lower percentage of multiple autoantibody positivity (72%, 92% and 93%) (p < 0.001). OGTT-stimulated C-peptide and glucose patterns of Glu(+) differed appreciably from Ind(+) and Glu(+)/Ind(+). Progression to diabetes occurred in 61% (46/76) of Glu(+) and 63% (71/113) of Ind(+). Even though Index60 ≥2.00 was not a Pathway to Prevention diagnostic criterion, Ind(+) had a 4 year cumulative diabetes incidence of 95% (95% CI 86%, 98%). CONCLUSIONS/INTERPRETATION: Participants in the Ind(+) group had more typical characteristics of type 1 diabetes than participants in the Glu(+) did and were as likely to be diagnosed. However, unlike Glu(+) participants, Ind(+) participants were not identified at the baseline OGTT.


Asunto(s)
Glucemia/metabolismo , Péptido C/sangre , Técnicas de Apoyo para la Decisión , Diabetes Mellitus Tipo 1/diagnóstico , Prueba de Tolerancia a la Glucosa , Islotes Pancreáticos/metabolismo , Adolescente , Adulto , Autoanticuerpos/sangre , Biomarcadores/sangre , Niño , Preescolar , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/inmunología , Progresión de la Enfermedad , Diagnóstico Precoz , Femenino , Humanos , Lactante , Islotes Pancreáticos/inmunología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Adulto Joven
15.
J Theor Biol ; 528: 110853, 2021 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-34358537

RESUMEN

Current clinician practice for thyroid hormone regulation of patients is based upon guesswork and experience rather than quantified analysis, which exposes patients under longer risk and discomfort. To quantitatively analyze the thyroid regulation for patients of different thyroid states, we develop a two-dimensional mathematical model that can be applied to analyze the dynamic behaviors of thyroid hormones with or without drug intervention. The unified model can be employed to study the regulation of TSH (thyroid-stimulating hormone) and FT4 (free thyroxine) for euthyroid (normal thyroid) subjects, Hashimoto's thyroiditis, and Graves' disease patients, respectively. The results suggest that the level of TPOAb (thyroid peroxidase antibody) may be a factor determining whether the patient would progress from euthyroid state to subclinical or clinical hypothyroidism, and that increased TRAb (TSH receptor antibody) may lead Graves' disease to deteriorate from the early stage to overt hyperthyroidism. Given the early blood-test data, we demonstrate the feasibility for healthcare professionals to apply our model in choosing an appropriate dosage regimen for patients to achieve the desired TSH and FT4 levels within a specified time frame. This proposed model has the potential to optimize personalized treatment and shorten the therapeutic time for patients suffering from Hashimoto's thyroiditis and Graves' disease.


Asunto(s)
Enfermedad de Graves , Medicina de Precisión , Autoanticuerpos , Enfermedad de Graves/tratamiento farmacológico , Humanos , Modelos Teóricos , Hormonas Tiroideas
16.
Stereotact Funct Neurosurg ; 99(5): 405-411, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33882507

RESUMEN

INTRODUCTION: Supratentorial primitive neuroectodermal tumor is a rare, aggressive intrinsic brain tumor with limited treatment options for recurrent disease. SRS as a treatment modality in the recurrent setting was investigated. METHODS: A retrospective review of 8 patients treated with SRS for local or distant recurrence of supratentorial PNET from 1999 to 2014 was conducted. RESULTS: Thirty-six tumors were treated in 15 sessions in 8 patients. The median patient age was 22.5 (interquartile range [IQR], 14.75-43.5 years) with a median 21-month period from diagnosis until SRS (IQR, 16-23.75 months). The median prescription isodose volume was 1.85 cm3 (IQR, 1.85-7.02 cm3); median tumor margin dose was 18 Gy (IQR 14-20 Gy); and median isocenters was 2 (range 1-13). No patients experienced adverse radiation effects. All but 1 patient died, and the median overall survival was 32 months (IQR, 26.75-53.5 months) with median overall survival following SRS of 9.5 months (IQR, 5.25-30 months). Univariate analysis failed to demonstrate a statistically significant association between age, number of gamma knife treatments, interval to gamma knife, and margin radiation dose with overall survival. DISCUSSION/CONCLUSION: This series supports the use of SRS in patients with recurrent supratentorial PNET following multimodal therapy.


Asunto(s)
Neoplasias Encefálicas , Tumores Neuroectodérmicos Primitivos , Radiocirugia , Neoplasias Encefálicas/cirugía , Preescolar , Humanos , Lactante , Recurrencia Local de Neoplasia/radioterapia , Recurrencia Local de Neoplasia/cirugía , Tumores Neuroectodérmicos Primitivos/radioterapia , Tumores Neuroectodérmicos Primitivos/cirugía , Estudios Retrospectivos
17.
Int J Mol Sci ; 22(4)2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33673278

RESUMEN

One-carbon (1C) metabolism provides methyl groups for the synthesis and/or methylation of purines and pyrimidines, biogenic amines, proteins, and phospholipids. Our understanding of how 1C pathways operate, however, pertains mostly to the (rat) liver. Here we report that transcripts for all bar two genes (i.e., BHMT, MAT1A) encoding enzymes in the linked methionine-folate cycles are expressed in all cell types within the ovarian follicle, oocyte, and blastocyst in the cow, sheep, and pig; as well as in rat granulosa cells (GCs) and human KGN cells (a granulosa-like tumor cell line). Betaine-homocysteine methyltransferase (BHMT) protein was absent in bovine theca and GCs, as was activity of this enzyme in GCs. Mathematical modeling predicted that absence of this enzyme would lead to more volatile S-adenosylmethionine-mediated transmethylation in response to 1C substrate (e.g., methionine) or cofactor provision. We tested the sensitivity of bovine GCs to reduced methionine (from 50 to 10 µM) and observed a diminished flux of 1C units through the methionine cycle. We then used reduced-representation bisulfite sequencing to demonstrate that this reduction in methionine during bovine embryo culture leads to genome-wide alterations to DNA methylation in >1600 genes, including a cohort of imprinted genes linked to an abnormal fetal-overgrowth phenotype. Bovine ovarian and embryonic cells are acutely sensitive to methionine, but further experimentation is required to determine the significance of interspecific variation in BHMT expression.


Asunto(s)
Blastocisto/metabolismo , Carbono/metabolismo , Metilación de ADN , Epigénesis Genética , Células de la Granulosa/metabolismo , Oocitos/metabolismo , Células Tecales/metabolismo , Animales , Bovinos , Femenino , Células Hep G2 , Humanos , Ratas , Porcinos
18.
Anal Chem ; 92(16): 11195-11203, 2020 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-32700898

RESUMEN

We describe a set of simple devices for surface-induced dissociation of proteins and protein complexes on three instrument platforms. All of the devices use a novel yet simple split lens geometry that is minimally invasive (requiring a few millimeters along the ion path axis) and is easier to operate than prior generations of devices. The split lens is designed to be small enough to replace the entrance lens of a Bruker FT-ICR collision cell, the dynamic range enhancement (DRE) lens of a Waters Q-IM-TOF, or the exit lens of a transfer multipole of a Thermo Scientific Extended Mass Range (EMR) Orbitrap. Despite the decrease in size and reduction in number of electrodes to 3 (from 10 to 12 in Gen 1 and ∼6 in Gen 2), we show sensitivity improvement in a variety of cases across all platforms while also maintaining SID capabilities across a wide mass and energy range. The coupling of SID, high resolution, and ion mobility is demonstrated for a variety of protein complexes of varying topologies.


Asunto(s)
Proteína C-Reactiva/análisis , Glutamato Deshidrogenasa/análisis , Piruvato Quinasa/análisis , Animales , Espectrometría de Masas/instrumentación , Espectrometría de Masas/métodos , Conejos
19.
J Neurooncol ; 149(2): 293-303, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32860156

RESUMEN

INTRODUCTION: WHO grades II (atypical) and III (malignant) meningiomas are associated with significant morbidity and mortality. The role of adjuvant radiotherapy (RT) in management remains controversial. The goal of this study was to evaluate the impact of adjuvant RT on 5-year survival in patients with atypical and malignant meningiomas. We secondarily aimed to assess contemporary practice patterns and the impact of sociodemographic factors on outcome. METHODS: We queried the National Cancer Database for patients ≥ 18 years of age with cranial atypical or malignant meningiomas from 2010 through 2015 who underwent surgical resection with or without adjuvant radiotherapy. Subjects with unknown WHO grade or radiation status and those not receiving any surgical procedure were excluded from analysis. RESULTS: The study includes 7486 patients, 6788 with atypical and 698 with malignant meningiomas. Overall 5-year survival was 76.9% (95% CI 75.5-78.3%) and 43.3% (95% CI 38.8-48.2%) among patients with WHO grades II and III meningiomas, respectively. Adjuvant RT correlated with improved survival in a multivariable model in patients with grade II tumors (HR 0.78; p = 0.029) regardless of the extent of resection. Age (HR 2.33; p < 0.001), male sex (HR 1.27; p < 0.001), Black race (HR 1.27; p = 0.011) and Charlson-Deyo Score ≥ 2 (1.35; p = 0.001) correlated with poorer survival whereas private insurance (HR 0.71; p < 0.001) correlated with improved survival. Adjuvant RT was also associated with improved 5-year survival among those with grade III tumors on univariate analysis (log-rank p = 0.006) but was underpowered for multivariable modeling. Utilization of adjuvant radiotherapy was only 28.4% and correlated with private insurance status. Academic institutions (25.3%) and comprehensive community cancer programs (21.4%) had lower radiotherapy utilization rates compared with integrated network cancer programs (30.5%) and community cancer programs (29.7%). CONCLUSIONS: Adjuvant RT may correlate with improved overall survival in patients with grades II and III intracranial meningiomas regardless of the extent of resection. There is poor utilization of adjuvant RT for patients with grades II and III meningiomas likely due to a paucity of quality data on the subject. These findings will be strengthened with prospective data evaluating the role of adjuvant RT.


Asunto(s)
Neoplasias Meníngeas/mortalidad , Meningioma/mortalidad , Pautas de la Práctica en Medicina/estadística & datos numéricos , Radioterapia Adyuvante/mortalidad , Sistema de Registros/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Neoplasias Meníngeas/patología , Neoplasias Meníngeas/radioterapia , Meningioma/patología , Meningioma/radioterapia , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Organización Mundial de la Salud , Adulto Joven
20.
Pediatr Diabetes ; 21(1): 120-127, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31617648

RESUMEN

Pronounced health disparities exist in type 1 diabetes (T1D) based on socioeconomic status (SES) yet there are a lack of programs designed to promote health equity for vulnerable communities. The All for ONE (Outreach, Networks, and Education) mentoring program was piloted pairing college students and publicly insured teenagers with T1D to assess feasibility as a possible intervention. There were 22 mentors recruited (mean age 20 ± 2 years; 17 [77%] females; mean HbA1c 8.4 ± 1.5%) and matched with mentees based on gender. There were 42 teens randomized to treatment and control groups including 22 teens in the treatment group (age 14 ± 2 years; 17 [77%] females; HbA1c 9.8 ± 2.3%) and 20 teens in the control group (age 14 ± 2 years; 15 [75%] females; HbA1c 8.9 ± 2.0%) followed over 9 months. Outcome measures included HbA1c and the Children's Hope Scale. The intervention included automated text reminders for blood glucose monitoring, text exchanges, social events with education, and clinic visits with mentors/mentees. Mean change in HbA1c for teens was +0.09% in the intervention group, compared with +0.28% in the control group (P = .61); college students had a reduction in HbA1c of -0.22% (P = .38). Treatment group teens had marked improvement in their hope for the future compared to control group teens (P = .04) and were more likely to attend clinic visits (P = .02). This program established feasibility for a model that could be replicated and modified for other types of settings. Additional research is warranted to study the potential long-term benefits of participating in the All for ONE mentoring program.


Asunto(s)
Diabetes Mellitus Tipo 1/terapia , Promoción de la Salud/métodos , Disparidades en el Estado de Salud , Mentores , Adolescente , Factores de Edad , Automonitorización de la Glucosa Sanguínea , Niño , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/psicología , Estudios de Factibilidad , Femenino , Hemoglobina Glucada/metabolismo , Esperanza , Humanos , Masculino , Grupo Paritario , Factores Socioeconómicos , Adulto Joven
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