136 research outputs found
Mixed germ cell tumour of testis: a case report with review of literature
Testicular tumours are rare neoplasm. Mixed germ cell tumour is the most common histological variant. Essentially, any admixture of the germ cell tumours as seen in pure form may be seen, one of the most common admixtures being embryonal carcinoma and teratoma. Unfortunately many of these patients present late usually with some complications. We present a rare case of mixed germ cell tumour with predominant embryonal carcinoma and yolk sac tumour in adolescent patient with multiple metastatic foci at the time of presentation
PERFORMANCE STUDY OF FLEXIBLE PAVEMENTS ON NON EXPANSIVE SOILS
As part of infrastructure development huge investment is being made on expansion of National highways and important roads across the country. For improvement of Highways two types of Pavements are commonly used in India viz., Flexible Pavements (Bituminous) and rigid pavements (Concrete). Flexible pavements are widely used in this country from the considerations of economy The performance of Flexible pavements depends largely on properties of original ground on which the pavement rests, the quality of materials used in the construction of various layers of pavement and quality assurance as per relevant specifications. In general any road after construction is basically evaluated by the performance in terms of unevenness index and structural stability over a period of time. The evaluation of these two important parameters will facilitate the clear understanding of performance of various materials used in the construction and to undertake suitable rehabilitation measures if necessary. Keywords: Expansive Soil, Flexible Pavement
Intrinsic mechanisms in the gating of resurgent Na+ currents
The resurgent component of the voltage-gated sodium current (
Bumblebees exhibit the memory spacing effect
Associative learning is key to how bees recognize and return to rewarding floral resources. It thus plays a major role in pollinator floral constancy and plant gene flow. Honeybees are the primary model for pollinator associative learning, but bumblebees play an important ecological role in a wider range of habitats, and their associative learning abilities are less well understood. We assayed learning with the proboscis extension reflex (PER), using a novel method for restraining bees (capsules) designed to improve bumblebee learning. We present the first results demonstrating that bumblebees exhibit the memory spacing effect. They improve their associative learning of odor and nectar reward by exhibiting increased memory acquisition, a component of long-term memory formation, when the time interval between rewarding trials is increased. Bombus impatiens forager memory acquisition (average discrimination index values) improved by 129% and 65% at inter-trial intervals (ITI) of 5 and 3 min, respectively, as compared to an ITI of 1 min. Memory acquisition rate also increased with increasing ITI. Encapsulation significantly increases olfactory memory acquisition. Ten times more foragers exhibited at least one PER response during training in capsules as compared to traditional PER harnesses. Thus, a novel conditioning assay, encapsulation, enabled us to improve bumblebee-learning acquisition and demonstrate that spaced learning results in better memory consolidation. Such spaced learning likely plays a role in forming long-term memories of rewarding floral resources
Generalization Mediates Sensitivity to Complex Odor Features in the Honeybee
Animals use odors as signals for mate, kin, and food recognition, a strategy which appears ubiquitous and successful despite the high intrinsic variability of naturally-occurring odor quantities. Stimulus generalization, or the ability to decide that two objects, though readily distinguishable, are similar enough to afford the same consequence [1], could help animals adjust to variation in odor signals without losing sensitivity to key inter-stimulus differences. The present study was designed to investigate whether an animal's ability to generalize learned associations to novel odors can be influenced by the nature of the associated outcome. We use a classical conditioning paradigm for studying olfactory learning in honeybees [2] to show that honeybees conditioned on either a fixed- or variable-proportion binary odor mixture generalize learned responses to novel proportions of the same mixture even when inter-odor differences are substantial. We also show that the resulting olfactory generalization gradients depend critically on both the nature of the stimulus-reward paradigm and the intrinsic variability of the conditioned stimulus. The reward dependency we observe must be cognitive rather than perceptual in nature, and we argue that outcome-dependent generalization is necessary for maintaining sensitivity to inter-odor differences in complex olfactory scenes
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Psilocybin and Motor Function: A Triple‐Blind, Dose‐Finding Study in Healthy Participants
Background: There has been a resurgence of research into the potential therapeutic benefits of psychedelics for
neuropsychiatric disorders. Classic psychedelics, such as
psilocybin, exert complex effects on higher cognitive
functions such as perception and awareness, but their
impact on motor function remains unexplored. Moreover,
there is a theoretical rationale for using psychedelics to
promote motor retraining in certain neuropsychiatric
conditions associated with motor dysfunction. This protocol paper outlines the first study to investigate the
feasibility and safety of performing movement tasks during the acute effects of psilocybin in healthy participants. The findings from this study will further our understanding of
the impact of psychedelics on motor function, and inform
future studies that combine classic psychedelics with
motor retraining in clinical populations.
Methods: 12 healthy participants will each receive three
doses of psilocybin (between 5 and 20 mg) in a randomized order, with each dose administered at least 1 week
apart. Participants, the trial physiotherapists, and statisticians will remain blinded to the psilocybin dose. A battery of measures assessing motor function will be completed during the acute drug effects. In addition, measures of safety, pre‐ and post‐dose resting‐state brain activity via functional magnetic resonance imaging, and participants' subjective experience will be assessed
Treatment of CoQ10 Deficient Fibroblasts with Ubiquinone, CoQ Analogs, and Vitamin C: Time- and Compound-Dependent Effects
Background: Coenzyme Q(10) (CoQ(10)) and its analogs are used therapeutically by virtue of their functions as electron carriers, antioxidant compounds, or both. However, published studies suggest that different ubiquinone analogs may produce divergent effects on oxidative phosphorylation and oxidative stress.Methodology/Principal Findings: To test these concepts, we have evaluated the effects of CoQ(10), coenzyme Q(2) (CoQ(2)), idebenone, and vitamin C on bioenergetics and oxidative stress in human skin fibroblasts with primary CoQ(10) deficiency. A final concentration of 5 mu M of each compound was chosen to approximate the plasma concentration of CoQ(10) of patients treated with oral ubiquinone. CoQ(10) supplementation for one week but not for 24 hours doubled ATP levels and ATP/ADP ratio in CoQ(10) deficient fibroblasts therein normalizing the bioenergetics status of the cells. Other compounds did not affect cellular bioenergetics. In COQ2 mutant fibroblasts, increased superoxide anion production and oxidative stress-induced cell death were normalized by all supplements.Conclusions/Significance: These results indicate that: 1) pharmacokinetics of CoQ(10) in reaching the mitochondrial respiratory chain is delayed; 2) short-tail ubiquinone analogs cannot replace CoQ(10) in the mitochondrial respiratory chain under conditions of CoQ(10) deficiency; and 3) oxidative stress and cell death can be counteracted by administration of lipophilic or hydrophilic antioxidants. The results of our in vitro experiments suggest that primary CoQ(10) deficiencies should be treated with CoQ(10) supplementation but not with short-tail ubiquinone analogs, such as idebenone or CoQ(2). Complementary administration of antioxidants with high bioavailability should be considered if oxidative stress is present
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