Carrion smell is strongly repugnant to humans and triggers distinct innate behaviors in many other species. This smell is mainly carried by two small aliphatic diamines, putrescine and cadaverine, ...which are generated by bacterial decarboxylation of the basic amino acids ornithine and lysine. Depending on the species, these diamines may also serve as feeding attractants, oviposition attractants, or social cues. Behavioral responses to diamines have not been investigated in zebrafish, a powerful model system for studying vertebrate olfaction. Furthermore, olfactory receptors that detect cadaverine and putrescine have not been identified in any species so far. Here, we show robust olfactory-mediated avoidance behavior of zebrafish to cadaverine and related diamines, and concomitant activation of sparse olfactory sensory neurons by these diamines. The large majority of neurons activated by low concentrations of cadaverine expresses a particular olfactory receptor, trace amine-associated receptor 13c (TAAR13c). Structure-activity analysis indicates TAAR13c to be a general diamine sensor, with pronounced selectivity for odd chains of medium length. This receptor can also be activated by decaying fish extracts, a physiologically relevant source of diamines. The identification of a sensitive zebrafish olfactory receptor for these diamines provides a molecular basis for studying neural circuits connecting sensation, perception, and innate behavior.
Gliomas synaptically integrate into neural circuits
. Previous research has demonstrated bidirectional interactions between neurons and glioma cells, with neuronal activity driving glioma growth
and ...gliomas increasing neuronal excitability
. Here we sought to determine how glioma-induced neuronal changes influence neural circuits underlying cognition and whether these interactions influence patient survival. Using intracranial brain recordings during lexical retrieval language tasks in awake humans together with site-specific tumour tissue biopsies and cell biology experiments, we find that gliomas remodel functional neural circuitry such that task-relevant neural responses activate tumour-infiltrated cortex well beyond the cortical regions that are normally recruited in the healthy brain. Site-directed biopsies from regions within the tumour that exhibit high functional connectivity between the tumour and the rest of the brain are enriched for a glioblastoma subpopulation that exhibits a distinct synaptogenic and neuronotrophic phenotype. Tumour cells from functionally connected regions secrete the synaptogenic factor thrombospondin-1, which contributes to the differential neuron-glioma interactions observed in functionally connected tumour regions compared with tumour regions with less functional connectivity. Pharmacological inhibition of thrombospondin-1 using the FDA-approved drug gabapentin decreases glioblastoma proliferation. The degree of functional connectivity between glioblastoma and the normal brain negatively affects both patient survival and performance in language tasks. These data demonstrate that high-grade gliomas functionally remodel neural circuits in the human brain, which both promotes tumour progression and impairs cognition.
Animal sensory systems are tightly adapted to the demands of their environment. In the visual domain, research has shown that many species have circuits and systems that exploit statistical ...regularities in natural visual signals. The zebrafish is a popular model animal in visual neuroscience, but relatively little quantitative data is available about the visual properties of the aquatic habitats where zebrafish reside, as compared to terrestrial environments. Improving our understanding of the visual demands of the aquatic habitats of zebrafish can enhance the insights about sensory neuroscience yielded by this model system. We analyzed a video dataset of zebrafish habitats captured by a stationary camera and compared this dataset to videos of terrestrial scenes in the same geographic area. Our analysis of the spatiotemporal structure in these videos suggests that zebrafish habitats are characterized by low visual contrast and strong motion when compared to terrestrial environments. Similar to terrestrial environments, zebrafish habitats tended to be dominated by dark contrasts, particularly in the lower visual field. We discuss how these properties of the visual environment can inform the study of zebrafish visual behavior and neural processing and, by extension, can inform our understanding of the vertebrate brain.
In the present study, identification of groundwater zones that are affected by anthropogenic contaminants based on litho-hydrogeological parameters has been attempted using multi-criteria decision ...analysis–analytical hierarchy process (MCDA–AHP) technique in an agriculturally intensive Arang block of Raipur district, Chhattisgarh, Central India. Litho-hydrogeological factors, such as geological and aquifer characteristics, land use–land cover, depth to water table, soil type, rainfall distribution, slope, geomorphological features, drainage density, elevation and lineament density parameters are considered for the delineation of anthropogenic contamination zones based on an integrated index model in Arc-GIS. Various input layers were assigned weights and then weight normalization process was adopted using Saaty’s AHP method to develop the integrated potential anthropogenic contamination zone (PACZ) map, based on the relative importance of anthropogenic contamination of groundwater. According to the proposed model majority of the study area falls under precarious zone, though certain areas fall under safe zone. In course of time, without proper planning the area could turn out to be moderately unsafe to unsafe zone. The PACZ map was validated with the fluoride concentration in groundwater as per National Rural Drinking Water Programme (NRDWP) report along with the measured nitrate concentration values. Model accuracy was achieved by agreement of about 82% of the fluoride values and 94% of the nitrate values with the proposed output map. Further validation of the model with fluoride and nitrate data was performed using computing similarity analysis with Pearson’s correlation coefficient which suggests anomalously higher concentrations of fluoride and nitrate ion concentration in certain areas of Arang block, which could be emanated from non-point anthropogenic sources. Additionally, Gibbs’s plot and saturation indices of fluorite and calcite suggest that groundwater chemistry is primarily controlled by aquifer lithological characteristics (rock–water interaction) and diffused anthropogenic contamination sources.
An unusual case of neural palatal swelling Poonja, Preethi A; Sattur, Atul P; Burde, Krishna N ...
International journal of health sciences,
07/2017, Volume:
11, Issue:
3
Journal Article
Peer reviewed
Open access
Neural tumors in the oral cavity occur both in the soft tissues and in the jaw bones. They occur as painless, smooth surface swelling in the soft tissues of the mouth, exhibiting a slow rate of ...growth and mild expansion of the cortical plates. Here, we report a rare case of a cellular variant of schwannoma in a young Indian female patient who presented with an asymptomatic nodule in the mid-palatine raphe region of the hard palate, mimicking a fibroma, thus creating a dilemma in the diagnosis.
Methaemoglobinaemia should be considered in all patients who are cyanotic and not responding to oxygen therapy. We report the case of a 25-year-old male who presented to the emergency room with ...alleged history of suicidal poisoning with 20 tablets of alprazolam (0.5mg) and anti-termite solution. At presentation he was drowsy, dyspnoeic and cyanosed. He was immediately intubated and intiated on mechanical ventilatory support. Oxygen saturation by pulse oximetry remained at 82% and did not improve even with a fraction of inspired oxygen of 1.0. Arterial blood was chocolate brown in colour. Arterial blood gas analysis revealed presence of significant saturation gap. Co-oxymetric analysis was done which revealed increased methaemoglobin levels following which methylene blue (100 mg) was given intravenously (IV) and symptoms improved. Patient was extubated the following day and was discharged in a haemodynamically stable state. Early diagnosis and antidotal treatment are pivotal in methaemoglobinaemia.
Abstract
Mitochondrial transcription factor A (TFAM) is essential for the maintenance, expression and transmission of mitochondrial DNA (mtDNA). However, mechanisms for the post-translational ...regulation of TFAM are poorly understood. Here, we show that TFAM is lysine acetylated within its high-mobility-group box 1, a domain that can also be serine phosphorylated. Using bulk and single-molecule methods, we demonstrate that site-specific phosphoserine and acetyl-lysine mimics of human TFAM regulate its interaction with non-specific DNA through distinct kinetic pathways. We show that higher protein concentrations of both TFAM mimics are required to compact DNA to a similar extent as the wild-type. Compaction is thought to be crucial for regulating mtDNA segregation and expression. Moreover, we reveal that the reduced DNA binding affinity of the acetyl-lysine mimic arises from a lower on-rate, whereas the phosphoserine mimic displays both a decreased on-rate and an increased off-rate. Strikingly, the increased off-rate of the phosphoserine mimic is coupled to a significantly faster diffusion of TFAM on DNA. These findings indicate that acetylation and phosphorylation of TFAM can fine-tune TFAM-DNA binding affinity, to permit the discrete regulation of mtDNA dynamics. Furthermore, our results suggest that phosphorylation could additionally regulate transcription by altering the ability of TFAM to locate promoter sites.
A pregnant woman undergoes physiological as well as psychological changes during this phase of life during which anxiety is a commonly faced mental condition. There is sufficient evidence on the ...association of pregnancy specific anxiety with adverse pregnancy outcomes. Studies on anxiety during pregnancy from low and middle income countries are limited.
This study included 380 pregnant women, having a confirmed pregnancy of less than 24 weeks without any obstetric complication, who were availing of antenatal care at a public sector hospital in Bangalore city. Pregnancy-related thoughts (PRT) scale was used to screen for anxiety. Details pertaining to sociodemographic data, obstetric history, psychosocial factors including social support, marital discord, domestic violence, consanguinity, history of catastrophic events, history of mental illness, current presence of depression and anxiety was obtained by means of electronic data capture using an Android-based App.
Out of 380 pregnant women, 195 (55.7%) were found to have pregnancy-related anxiety. Lower socioeconomic status, low social support and depression emerged as significant determinants of anxiety.
The prevalence of anxiety was fairly high in the study population and isp therefore an important public health concern. Pregnancy-related anxiety must be identified early during routine antenatal care to prevent any untoward pregnancy outcomes.
The COVID-19 pandemic has threatened the humanity at a global level to a large extent by the burden of the disease with significant mortality and to a certain extent as a byproduct of the necessary ...efforts to contain the same. There is a significant impact on the health care system, as we not only have to contain pandemic, but continue to treat our non-COVID-19 patients in a safe and responsible manner. Ophthalmology practice in general and glaucoma in particular needs certain modifications and additional precautions while examining as well as managing these patients keeping their and our safety in mind. As the lockdown relaxations are in vogue we need to learn how to deal with our regular patients as well in addition to emergency care. This paper presents the consensus-based guidelines by an expert panel on how to restart glaucoma practice during this COVID-19 time. These guidelines will be applicable across the country and should help ophthalmologists and glaucoma specialist to restart their practices while safeguarding the patients and their own selves from getting infected.
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