850 research outputs found

    A Phase 1 Trial of CNDO-109-Activated Natural Killer Cells in Patients with High-Risk Acute Myeloid Leukemia

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    Natural killer (NK) cells are an emerging immunotherapy approach to acute myeloid leukemia (AML); however, the optimal approach to activate NK cells before adoptive transfer remains unclear. Human NK cells that are primed with the CTV-1 leukemia cell line lysate CNDO-109 exhibit enhanced cytotoxicity against NK cell–resistant cell lines. To translate this finding to the clinic, CNDO-109–activated NK cells (CNDO-109-NK cells) isolated from related HLA-haploidentical donors were evaluated in a phase 1 dose-escalation trial at doses of 3 × 105 (n = 3), 1 × 106 (n = 3), and 3 × 106 (n = 6) cells/kg in patients with AML in first complete remission (CR1) at high risk for recurrence. Before CNDO-109-NK cell administration, patients were treated with lymphodepleting fludarabine/cyclophosphamide. CNDO-109-NK cells were well tolerated, and no dose-limiting toxicities were observed at the highest tested dose. The median relapse-free survival (RFS) by dose level was 105 (3 × 105), 156 (1 × 106), and 337 (3 × 106) days. Two patients remained relapse-free in post-trial follow-up, with RFS durations exceeding 42.5 months. Donor NK cell microchimerism was detected on day 7 in 10 of 12 patients, with 3 patients having evidence of donor cells on day 14 or later. This trial establishes that CNDO-109-NK cells generated from related HLA haploidentical donors, cryopreserved, and then safely administered to AML patients with transient persistence without exogenous cytokine support. Three durable complete remissions of 32.6 to 47.6+ months were observed, suggesting additional clinical investigation of CNDO-109-NK cells for patients with myeloid malignancies, alone or in combination with additional immunotherapy strategies, is warranted

    Mechanical homeostasis regulating adipose tissue volume

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    <p>Abstract</p> <p>Background</p> <p>The total body adipose tissue volume is regulated by hormonal, nutritional, paracrine, neuronal and genetic control signals, as well as components of cell-cell or cell-matrix interactions. There are no known locally acting homeostatic mechanisms by which growing adipose tissue might adapt its volume.</p> <p>Presentation of the hypothesis</p> <p>Mechanosensitivity has been demonstrated by mesenchymal cells in tissue culture. Adipocyte differentiation has been shown to be inhibited by stretching in vitro, and a pathway for the response has been elucidated. In humans, intermittent stretching of skin for reconstructional purposes leads to thinning of adipose tissue and thickening of epidermis – findings matching those observed in vitro in response to mechanical stimuli. Furthermore, protracted suspension of one leg increases the intermuscular adipose tissue volume of the limb. These findings may indicate a local homeostatic adipose tissue volume-regulating mechanism based on movement-induced reduction of adipocyte differentiation. This function might, during evolution, have been of importance in confined spaces, where overgrowth of adipose tissue could lead to functional disturbance, as for instance in the turtle. In humans, adipose tissue near muscle might in particular be affected, for instance intermuscularly, extraperitoneally and epicardially. Mechanical homeostasis might also contribute to protracted maintainment of soft tissue shape in the face and neck region.</p> <p>Testing of the hypothesis</p> <p>Assessment of messenger RNA-expression of human adipocytes following activity in adjacent muscle is planned, and study of biochemical and volumetric adipose tissue changes in man are proposed.</p> <p>Implications of the hypothesis</p> <p>The interpretation of metabolic disturbances by means of adipose tissue might be influenced. Possible applications in the head and neck were discussed.</p

    Telomerase activity in melanoma and non-melanoma skin cancer

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    Telomeres are specialized structures consisting of repeat arrays of TTAGGGn located at the ends of chromosomes. They are essential for chromosome stability and, in the majority of normal somatic cells, telomeres shorten with each cell division. Most immortalized cell lines and tumours reactivate telomerase to stabilize the shortening chromosomes. Telomerase activation is regarded as a central step in carcinogenesis and, here, we demonstrate telomerase activation in premalignant skin lesions and also in all forms of skin cancer. Telomerase activation in normal skin was a rare event, and among 16 samples of normal skin (one with a history of chronic sun exposure) 12.5% (2 out of 16) exhibited telomerase activity. One out of 16 (6.25%) benign proliferative lesions, including viral and seborrhoeic wart samples, had telomerase activity. In premalignant actinic keratoses and Bowen's disease, 42% (11 out of 26) of samples exhibited telomerase activity. In the basal cell carcinoma and cutaneous malignant melanoma (CMM) lesions, telomerase was activated in 77% (10 out of 13) and 69% (22 out of 32) respectively. However, only 25% (3 out of 12) of squamous cell carcinomas (SCC) had telomerase activity. With the exception of one SCC sample, telomerase activity in a positive control cell line derived from a fibrosarcoma (HT1080) was not inhibited when mixed with the telomerase-negative SCC or CMM extracts, indicating that, overall, Taq polymerase and telomerase inhibitors were not responsible for the negative results. Mean telomere hybridizing restriction fragment (TRF) analysis was performed in a number of telomerase-positive and -negative samples and, although a broad range of TRF sizes ranging from 3.6 to 17 kb was observed, a relationship between telomerase status and TRF size was not found

    Are tutor behaviors in problem-based learning stable? A generalizability study of social congruence, expertise and cognitive congruence

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    The purpose of this study was to investigate the stability of three distinct tutor behaviors (1) use of subject-matter expertise, (2) social congruence and (3) cognitive congruence, in a problem-based learning (PBL) environment. The data comprised the input from 16,047 different students to a survey of 762 tutors administered in three consecutive semesters. Over the three semesters each tutor taught two of the same course and one different course. A generalizability study was conducted to determine whether the tutor behaviors were generalizable across the three measurement occasions. The results indicate that three semesters are sufficient to make generalizations about all three tutor behaviors. In addition the results show that individual differences between tutors account for the greatest differences in levels of expertise, social congruence and cognitive congruence. The study concludes that tutor behaviors are fairly consistent in PBL and somewhat impervious to change. Implications of these findings for tutor training are discussed

    Nasal Chemosensory-Stimulation Evoked Activity Patterns in the Rat Trigeminal Ganglion Visualized by In Vivo Voltage-Sensitive Dye Imaging

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    Mammalian nasal chemosensation is predominantly mediated by two independent neuronal pathways, the olfactory and the trigeminal system. Within the early olfactory system, spatiotemporal responses of the olfactory bulb to various odorants have been mapped in great detail. In contrast, far less is known about the representation of volatile chemical stimuli at an early stage in the trigeminal system, the trigeminal ganglion (TG), which contains neurons directly projecting to the nasal cavity. We have established an in vivo preparation that allows high-resolution imaging of neuronal population activity from a large region of the rat TG using voltage-sensitive dyes (VSDs). Application of different chemical stimuli to the nasal cavity elicited distinct, stimulus-category specific, spatiotemporal activation patterns that comprised activated as well as suppressed areas. Thus, our results provide the first direct insights into the spatial representation of nasal chemosensory information within the trigeminal ganglion imaged at high temporal resolution

    Neuroinflammation, Mast Cells, and Glia: Dangerous Liaisons

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    The perspective of neuroinflammation as an epiphenomenon following neuron damage is being replaced by the awareness of glia and their importance in neural functions and disorders. Systemic inflammation generates signals that communicate with the brain and leads to changes in metabolism and behavior, with microglia assuming a pro-inflammatory phenotype. Identification of potential peripheral-to-central cellular links is thus a critical step in designing effective therapeutics. Mast cells may fulfill such a role. These resident immune cells are found close to and within peripheral nerves and in brain parenchyma/meninges, where they exercise a key role in orchestrating the inflammatory process from initiation through chronic activation. Mast cells and glia engage in crosstalk that contributes to accelerate disease progression; such interactions become exaggerated with aging and increased cell sensitivity to stress. Emerging evidence for oligodendrocytes, independent of myelin and support of axonal integrity, points to their having strong immune functions, innate immune receptor expression, and production/response to chemokines and cytokines that modulate immune responses in the central nervous system while engaging in crosstalk with microglia and astrocytes. In this review, we summarize the findings related to our understanding of the biology and cellular signaling mechanisms of neuroinflammation, with emphasis on mast cell-glia interactions

    Dysregulation of DGCR6 and DGCR6L: psychopathological outcomes in chromosome 22q11.2 deletion syndrome

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    Chromosome 22q11.2 deletion syndrome (22q11DS) is the most common microdeletion syndrome in humans. It is typified by highly variable symptoms, which might be explained by epigenetic regulation of genes in the interval. Using computational algorithms, our laboratory previously predicted that DiGeorge critical region 6 (DGCR6), which lies within the deletion interval, is imprinted in humans. Expression and epigenetic regulation of this gene have not, however, been examined in 22q11DS subjects. The purpose of this study was to determine if the expression levels of DGCR6 and its duplicate copy DGCR6L in 22q11DS subjects are associated with the parent-of-origin of the deletion and childhood psychopathologies. Our investigation showed no evidence of parent-of-origin-related differences in expression of both DGCR6 and DGCR6L. However, we found that the variability in DGCR6 expression was significantly greater in 22q11DS children than in age and gender-matched control individuals. Children with 22q11DS who had anxiety disorders had significantly lower DGCR6 expression, especially in subjects with the deletion on the maternal chromosome, despite the lack of imprinting. Our findings indicate that epigenetic mechanisms other than imprinting contribute to the dysregulation of these genes and the associated childhood psychopathologies observed in individuals with 22q11DS. Further studies are now needed to test the usefulness of DGCR6 and DGCR6L expression and alterations in the epigenome at these loci in predicting childhood anxiety and associated adult-onset pathologies in 22q11DS subjects

    Complex Evolutionary History of the Aeromonas veronii Group Revealed by Host Interaction and DNA Sequence Data

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    Aeromonas veronii biovar sobria, Aeromonas veronii biovar veronii, and Aeromonas allosaccharophila are a closely related group of organisms, the Aeromonas veronii Group, that inhabit a wide range of host animals as a symbiont or pathogen. In this study, the ability of various strains to colonize the medicinal leech as a model for beneficial symbiosis and to kill wax worm larvae as a model for virulence was determined. Isolates cultured from the leech out-competed other strains in the leech model, while most strains were virulent in the wax worms. Three housekeeping genes, recA, dnaJ and gyrB, the gene encoding chitinase, chiA, and four loci associated with the type three secretion system, ascV, ascFG, aexT, and aexU were sequenced. The phylogenetic reconstruction failed to produce one consensus tree that was compatible with most of the individual genes. The Approximately Unbiased test and the Genetic Algorithm for Recombination Detection both provided further support for differing evolutionary histories among this group of genes. Two contrasting tests detected recombination within aexU, ascFG, ascV, dnaJ, and gyrB but not in aexT or chiA. Quartet decomposition analysis indicated a complex recent evolutionary history for these strains with a high frequency of horizontal gene transfer between several but not among all strains. In this study we demonstrate that at least for some strains, horizontal gene transfer occurs at a sufficient frequency to blur the signal from vertically inherited genes, despite strains being adapted to distinct niches. Simply increasing the number of genes included in the analysis is unlikely to overcome this challenge in organisms that occupy multiple niches and can exchange DNA between strains specialized to different niches. Instead, the detection of genes critical in the adaptation to specific niches may help to reveal the physiological specialization of these strains

    Prokineticin 2 Regulates the Electrical Activity of Rat Suprachiasmatic Nuclei Neurons

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    Neuropeptide signaling plays roles in coordinating cellular activities and maintaining robust oscillations within the mammalian suprachiasmatic nucleus (SCN). Prokineticin2 (PK2) is a signaling molecule from the SCN and involves in the generation of circadian locomotor activity. Prokineticin receptor 2 (PKR2), a receptor for PK2, has been shown to be expressed in the SCN. However, very little is known about the cellular action of PK2 within the SCN. In the present study, we investigated the effect of PK2 on spontaneous firing and miniature inhibitory postsynaptic currents (mIPSCs) using whole cell patch-clamp recording in the SCN slices. PK2 dose-dependently increased spontaneous firing rates in most neurons from the dorsal SCN. PK2 acted postsynaptically to reduce Ξ³-aminobutyric acid (GABA)-ergic function within the SCN, and PK2 reduced the amplitude but not frequency of mIPSCs. Furthermore, PK2 also suppressed exogenous GABA-induced currents. And the inhibitory effect of PK2 required PKC activation in the postsynaptic cells. Our data suggest that PK2 could alter cellular activities within the SCN and may influence behavioral and physiological rhythms
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