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1.
Clin Cancer Res ; 28(12): 2567-2578, 2022 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-35395080

RESUMEN

PURPOSE: PD-L1 is upregulated in glioblastoma and supports immunosuppression. We evaluated PD-L1 blockade with durvalumab among glioblastoma cohorts and investigated potential biomarkers. PATIENTS AND METHODS: MGMT unmethylated newly diagnosed patients received radiotherapy plus durvalumab (cohort A; n = 40). Bevacizumab-naïve, recurrent patients received durvalumab alone (cohort B; n = 31) or in combination with standard bevacizumab (cohort B2; n = 33) or low-dose bevacizumab (cohort B3; n = 33). Bevacizumab-refractory patients received durvalumab plus bevacizumab (cohort C; n = 22). Primary endpoints were: OS-12 (A), PFS-6 (B, B2, B3), and OS-6 (C). Exploratory biomarkers included: a systematic, quantitative, and phenotypic evaluation of circulating immune cells; tumor mutational burden (TMB); and tumor immune activation signature (IAS). RESULTS: No cohort achieved the primary efficacy endpoint. Outcome was comparable among recurrent, bevacizumab-naïve cohorts. No unexpected toxicities were observed. A widespread reduction of effector immune cell subsets was noted among recurrent patients compared with newly diagnosed patients that was partially due to dexamethasone use. A trend of increased CD8+Ki67+ T cells at day 15 was noted among patients who achieved the primary endpoint and were not on dexamethasone. Neither TMB nor IAS predicted outcome. CONCLUSIONS: Patients with recurrent glioblastoma have markedly lower baseline levels of multiple circulating immune cell subsets compared with newly diagnosed patients. An early increase in systemic Ki67+CD8+ cells may warrant further evaluation as a potential biomarker of therapeutic benefit among patients with glioblastoma undergoing checkpoint therapy. Dexamethasone decreased immune cell subsets. PD-L1 blockade and combination with standard or reduced dose bevacizumab was ineffective.


Asunto(s)
Dexametasona , Glioblastoma , Recurrencia Local de Neoplasia , Anticuerpos Monoclonales , Antígeno B7-H1/antagonistas & inhibidores , Bevacizumab/uso terapéutico , Biomarcadores de Tumor/análisis , Dexametasona/uso terapéutico , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/patología , Humanos , Antígeno Ki-67 , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología
2.
MicroPubl Biol ; 20212021.
Artículo en Inglés | MEDLINE | ID: mdl-34712912

RESUMEN

Ultracold storage is widely used to preserve genetic stocks. Standard cryopreservation methods for the nematode C. elegans are vulnerable to refrigeration failures, which can result in the loss of stock viability due to freeze-thaw damage. In previous work our laboratory developed a method for cryopreserving worms in a dehydrated form that remains viable after multiple freeze-thaw cycles. However, strains preserved in this manner can be recovered only once from each cryopreservation tube. Here we describe a cryopreservation method in which C. elegans are dehydrated in a granular medium (cornmeal) prior to freezing. To recover worms, a small fraction (~1%) of the medium may be removed with the remainder returned to cold storage. Our improved cryopreservation method is not only resistant to refrigeration failures but also greatly increases the number of recoveries per tube compared to current methods.

3.
Horm Behav ; 102: 69-75, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29750970

RESUMEN

Testosterone plays a key role in the expression of male sex behavior by influencing cellular activity and synapses within the magnocellular medial preoptic nucleus (MPN mag), a sub-nucleus of the medial preoptic area (MPOA) in the Syrian hamster. Although the mechanisms underlying hormonally-induced synaptic plasticity in this region remain elusive, the data suggests that an increase in synaptic density may mediate testosterone's effects on copulation. As brain derived neurotrophic factor (BDNF) plays an integral role in regulating synaptic plasticity and gonadal steroids regulate the levels of BDNF, we hypothesize that BDNF may mediate the effects of gonadal hormones on copulatory behavior. To test this hypothesis, we infused BDNF or controls into the MPN mag of long-term castrates. Our results indicate that BDNF, but not the controls, restored copulatory behavior in castrated male Syrian hamsters. Furthermore, the rise of BDNF expression in the MPOA preceded the rise of synaptophysin following testosterone replacement in castrated males. These data are consistent with our hypothesis, implicating a role for BDNF in mediating testosterone's action on copulation and suggest that the delay in testosterone's restoration of copulation is, in part, due to the delay in the increase of BDNF and synaptophysin.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/administración & dosificación , Copulación/efectos de los fármacos , Orquiectomía , Área Preóptica/efectos de los fármacos , Conducta Sexual Animal/efectos de los fármacos , Animales , Cricetinae , Hormonas Esteroides Gonadales/metabolismo , Infusiones Intraventriculares , Masculino , Mesocricetus , Orquiectomía/veterinaria , Testosterona/metabolismo
4.
J Am Coll Nutr ; 37(8): 659-669, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29702032

RESUMEN

Objective: Dietary pattern changes, as a part of a healthy lifestyle, may improve weight management. The objective of this study was to examine the effect of midmorning puree snacks varying in macronutrient composition and energy content on subjective appetite, food intake, and glycemic and insulin responses in healthy adults.Method: In a randomized, repeated measures crossover design, 6 treatments (snack skipping and purees: control [186 kcal], maltodextrin [272 kcal], whey protein [201 kcal], oat [276 kcal], and coconut oil [276 kcal]) were administered to 23 normal weight adults (n = 14 males, n = 9 females). Subjective appetite, blood glucose, and insulin responses were measured at regular intervals for 2 hours immediately followed by an ad libitum pizza lunch. In vitro digestion experiments were conducted to corroborate results of the human trial.Results: Compared to snack skipping, all snack treatments similarly reduced subjective average appetite (net area under the curve), but only oat (p < 0.032) and coconut oil (p < 0.031) purees significantly decreased test meal food intake. However, caloric compensation did not differ among snack treatments (p < 0.73). Both blood glucose (incremental area under the curve [iAUC]; p < 0.0001) and serum insulin (iAUC; p < 0.0001) were affected by treatment. A positive correlation was found between blood glucose iAUC and in vitro glucose release (r = 0.993, p < 0.0001). The release of free fatty acids (FFAs) was sustained, and oats were difficult to disintegrate during in vitro digestion.Conclusions: Compared with snack skipping, coconut oil and oat puree snacks suppressed short-term food intake, which was likely due to the sustained release of FFA and slowly digestible oats, respectively. Our in vitro digestion model predicted the relative differences in the glycemic response in vivo.

5.
Protein Sci ; 26(4): 677-699, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28054422

RESUMEN

Protein function identification remains a significant problem. Solving this problem at the molecular functional level would allow mechanistic determinant identification-amino acids that distinguish details between functional families within a superfamily. Active site profiling was developed to identify mechanistic determinants. DASP and DASP2 were developed as tools to search sequence databases using active site profiling. Here, TuLIP (Two-Level Iterative clustering Process) is introduced as an iterative, divisive clustering process that utilizes active site profiling to separate structurally characterized superfamily members into functionally relevant clusters. Underlying TuLIP is the observation that functionally relevant families (curated by Structure-Function Linkage Database, SFLD) self-identify in DASP2 searches; clusters containing multiple functional families do not. Each TuLIP iteration produces candidate clusters, each evaluated to determine if it self-identifies using DASP2. If so, it is deemed a functionally relevant group. Divisive clustering continues until each structure is either a functionally relevant group member or a singlet. TuLIP is validated on enolase and glutathione transferase structures, superfamilies well-curated by SFLD. Correlation is strong; small numbers of structures prevent statistically significant analysis. TuLIP-identified enolase clusters are used in DASP2 GenBank searches to identify sequences sharing functional site features. Analysis shows a true positive rate of 96%, false negative rate of 4%, and maximum false positive rate of 4%. F-measure and performance analysis on the enolase search results and comparison to GEMMA and SCI-PHY demonstrate that TuLIP avoids the over-division problem of these methods. Mechanistic determinants for enolase families are evaluated and shown to correlate well with literature results.


Asunto(s)
Bases de Datos de Proteínas , Glutatión Transferasa/química , Glutatión Transferasa/genética , Fosfopiruvato Hidratasa/química , Fosfopiruvato Hidratasa/genética , Análisis de Secuencia de Proteína/métodos
6.
Instr Sci ; 43(6): 709-735, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26848192

RESUMEN

Adults' gestures support children's learning in problem-solving tasks, but gestures may be differentially useful to children of different ages, and different features of gestures may make them more or less useful to children. The current study investigated parents' use of gestures to support their young children (1.5 - 6 years) in a block puzzle task (N = 126 parent-child dyads), and identified patterns in parents' gesture use indicating different gestural strategies. Further, we examined the effect of child age on both the frequency and types of gestures parents used, and on their usefulness to support children's learning. Children attempted to solve the puzzle independently before and after receiving help from their parent; half of the parents were instructed to sit on their hands while they helped. Parents who could use their hands appear to use gestures in three strategies: orienting the child to the task, providing abstract information, and providing embodied information; further, they adapted their gesturing to their child's age and skill level. Younger children elicited more frequent and more proximal gestures from parents. Despite the greater use of gestures with younger children, it was the oldest group (4.5-6.0 years) who were most affected by parents' gestures. The oldest group was positively affected by the total frequency of parents' gestures, and in particular, parents' use of embodying gestures (indexes that touched their referents, representational demonstrations with object in hand, and physically guiding child's hands). Though parents rarely used the embodying strategy with older children, it was this strategy which most enhanced the problem-solving of children 4.5 - 6 years.

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