Chemical Messengers Research Articles

Transiently increased serotonin has modest or no effects on bone mass accrual in growing female C57BL6/J or growing male and female Lrp5A214V mice.

Serotonin (5HT) is a chemical messenger with biologic activities affecting multiple organs. Within the skeletal system, studies in mice and humans suggest blood 5HT levels affect bone, with elevations impairing and reductions enhancing bone accrual. Other studies, however, have not supported this hypothesis. Recently, administering 5HT to a Piezo1 mutant mouse strain with hyposerotonemia, intestinal dysmotility, and a doubling of femoral trabecular bone mass at 2months of age, was reported to return the animals' intestinal motility and bone mass to normal. However, whether the 5HT directly affected bone metabolism or indirectly affected metabolism by improving intestinal function was not determined. Therefore, we administered 5HT to mice with normal intestinal function. We randomized female C57BL6/J mice and male and female mice that have increased bone mass due to a missense mutation in the WNT co-receptor LRP5 (Lrp5A214V) to receive 5HT or vehicle via daily IP injection from 4weeks to 8weeks of age. We did not observe consistent significant changes for distal femur trabecular, midshaft femur cortical, or vertebral body trabecular bone mass between 5HT treated and vehicle treated mice of either genotype. These data are compatible with other studies that have not observed a correlation between blood 5HT level and bone mass.

Auxin response factors in plant adaptation to drought and salinity stress.

Salinity and drought stresses affect plant growth worldwide and limit crop production. Auxin is crucial in regulating plants' salinity and drought stress adaptative response. As a chemical messenger, auxin influences gene expression through a family of functionally distinct transcription factors, the DNA-binding AUXIN RESPONSE FACTORS (ARFs). Various studies have revealed the important roles of ARFs in regulating drought and salinity stress responses in plants. Different ARFs regulate soluble sugar content, promote root development, and maintain chlorophyll content under drought and saline stress conditions to help plants adapt to these stresses. The functional characterization of ARFs pertaining to the regulation of drought and salinity stress responses is still in its infancy. Interestingly, the small RNA-mediated post-transcriptional regulation of ARF expression has been shown to influence plant responses to both stresses. The current knowledge on the diverse roles of ARFs in conferring specificity to auxin-mediated drought and salinity stress responses has not been reviewed to date. In this review, we summarize the recent research concerning the role of ARFs in response to drought and salinity stresses: gene expression patterns, functional characterization, and post-transcriptional regulation under drought and salinity stresses. We have also reviewed the modulation of ARF expression by other molecular regulators in the context of drought and salt stress signaling.

Heavy metal induced regulation of plant biology: Recent insights.

The presence of different forms of heavy metals in the earth crust is very primitive and probably associated with the origin of plant life. However, since the beginning of human civilisation, heavy metal use and its contamination to all living systems on earth have significantly increased due to human anthropogenic activities. Heavy metals are nonbiodegradable, which directly or indirectly impact photosynthesis, antioxidant system, mineral nutrition status, phytohormones and amino acid-derived molecules. Due to the toxic behaviour of some heavy metals, the endogenous status of chemical messengers like phytohormones may get significantly influenced, leading to harmful impacts on plant growth, development and overall yield of the plants. It has been noticed that exogenous application of phytohormones, that is, abscisic acid, salicylic acid, auxins, brassinosteroids, cytokinins, ethylene and gibberellins can positively regulate the heavy metal toxicity in plants through the regulation of the ascorbate-glutathione cycle, nitrogen metabolism, proline metabolisms, transpiration rate, and cell division. Furthermore, it may also restrict the entry of heavy metals into the plant cells, which aids in the recovery of plant growth and productivity. Besides these, some defence molecules also assist the plant in dealing with heavy metal toxicity. Therefore, the present review aims to bridge the knowledge gap in this context and present outstanding discoveries related to plant life supportive processes during stressful conditions including phytohormones and heavy metal crosstalk along with suggestions for future research in this field.

Role of radiation-induced rescue effect in radiation field size effect

The present paper reviewed the role of radiation-induced rescue effect (RIRE) in radiation field size effect. “Radiation field size effect” refers to the phenomenon that the radiobiological effects of ionizing radiation depend on the size of the irradiated area, besides depending on the equivalent dose. RIRE refers to the mitigation of detrimental effects in irradiated cells after receiving signals from non-irradiated bystander cells, or after receiving signals from the medium which has previously conditioned the non-irradiated bystander cells. The present paper will first give a brief review on RIRE, including the definition and classification of RIRE, as well as the signalling pathways and chemical messengers which have been identified for RIRE, and will then give a review of selected literature related to radiation field size effects. Discussion as well as some thoughts on future priorities and directions of research in the role of RIRE in radiation field size effect will then be presented.

Beyond the Calorie Paradigm: Taking into Account in Practice the Balance of Fat and Carbohydrate Oxidation during Exercise?

Recent literature shows that exercise is not simply a way to generate a calorie deficit as an add-on to restrictive diets but exerts powerful additional biological effects via its impact on mitochondrial function, the release of chemical messengers induced by muscular activity, and its ability to reverse epigenetic alterations. This review aims to summarize the current literature dealing with the hypothesis that some of these effects of exercise unexplained by an energy deficit are related to the balance of substrates used as fuel by the exercising muscle. This balance of substrates can be measured with reliable techniques, which provide information about metabolic disturbances associated with sedentarity and obesity, as well as adaptations of fuel metabolism in trained individuals. The exercise intensity that elicits maximal oxidation of lipids, termed LIPOXmax, FATOXmax, or FATmax, provides a marker of the mitochondrial ability to oxidize fatty acids and predicts how much fat will be oxidized over 45–60 min of low- to moderate-intensity training performed at the corresponding intensity. LIPOXmax is a reproducible parameter that can be modified by many physiological and lifestyle influences (exercise, diet, gender, age, hormones such as catecholamines, and the growth hormone-Insulin-like growth factor I axis). Individuals told to select an exercise intensity to maintain for 45 min or more spontaneously select a level close to this intensity. There is increasing evidence that training targeted at this level is efficient for reducing fat mass, sparing muscle mass, increasing the ability to oxidize lipids during exercise, lowering blood pressure and low-grade inflammation, improving insulin secretion and insulin sensitivity, reducing blood glucose and HbA1c in type 2 diabetes, and decreasing the circulating cholesterol level. Training protocols based on this concept are easy to implement and accept in very sedentary patients and have shown an unexpected efficacy over the long term. They also represent a useful add-on to bariatric surgery in order to maintain and improve its weight-lowering effect. Additional studies are required to confirm and more precisely analyze the determinants of LIPOXmax and the long-term effects of training at this level on body composition, metabolism, and health.

Dynamics of sexual development in teleosts with a note on Mugilcephalus

The process of sex determination (SD) and sex differentiation (Sd) with associated sex-specific behaviour in teleosts is brought about by genetic factors and environmental factors under the influence of chemical messengers. SD is initiated by inherited genes, which in turn influence Sd by the production of hormones. To understand the plasticity of SD in fishes, the functional role of genes must be clearly elucidated. During early development, the dimorphic expression of male and female are mediated by the differentially sexualized brain. In mammals, SD region (SDR) on the Y chromosome (SRY) can be considered as male-specific copy of SOX3 and in the absence of SRY in teleosts suggests SD might be regulated by alternate genes. DM (doublesex/mab)-related genes, AMH (anti-mullerian hormone), TGF-b (transforming growth factor beta), GSDF (gonadal soma derived growth factor) and other genes (around 18) located in chromosomes of teleosts are found to be responsible for SD. The SD gene, sdY (sexually dimorphic on the Y chromosome) has been detected in more than 15 salmonid species, and in medaka and tilapia SD system is governed by heterogametic mechanism. In mullet, Mugil cephalus Dor et al. identified 27 SDR genes and suggested to be potential candidate genes for SD. Recently whole-genome sequencing data were produced from mullet and assembled into a draft genome sequence in which >30 loci are potentially associated with SD. Further analysis is required to know the involvement of each sex-biased gene for its functional influence on sex. Investigators attempted to know the sex-linkage group in tilapia and found that 2 linkage group i.e. LG1 and LG22 show SD loci, whereas in mullet it was documented that LG8 is the SD loci. Rigorous study with all male population(YY) or knockout of male marker gene, might give conclusive understanding on SD in future. The review highlights the absence of genomic understanding of SD and SDR genes for futuristic direction of research.

Harnessing Fe3O4 Screen-Printed Modified Electrode Sensor for Detecting Epinephrine in Buff Orpington Rooster and Rhodes Island White Broiler

Nano-scale detection and characterization of neurotransmitters from real samples is a novel analytical technique with multiple applications in the field of nano-biotechnology. This in-situ electrochemical sensing tool has growing advantages of high reproducibility, rapid response, superior sensitivity, selectivity, accuracy, and miniaturization. A screen-printed iron oxide (Fe3O4) modified electrode was harnessed in this study for detecting epinephrine (EP), a chemical messenger or signalling neuro transmitting molecule, from two breeds of chickens. The fabricated sensor was used for the analysis of EP in the real and unspiked samples. UV-visible spectroscopy, Fourier-Transform infrared spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), and Scanning Electron Microscopy (SEM) were used for characterizing the surface of nanoparticles prior to modification of screen-printed silver electrode (SPSE). The XRD diffractogram of Fe3O4 nanoparticles showed peaks at 30.1°, 35.7°, 43.3°, 53.9°, 57.5°, and 63.0°, corresponding to Miller indices of 220, 311, 400, 422, 511, and 440, respectively. This diffraction pattern indicates that the Fe3O4 nanoparticles have a spinel structure. Simultaneous detection of EP in the presence of ascorbic acid was obtained from Fe3O4 electrode. Further result shows a corresponding rise in oxidation peak current (Ipa) of EP with an increase in its concentration and scan rate of 25–400 mVs−1 confirming catalytic properties of the modified electrode towards EP. Our findings demonstrate that the fabricated sensor used for detecting EP in blood serum, breast muscle, and visceral organs of both chicken breeds produced better recovery.

Unraveling the Role of Sex Hormones on Keratinocyte Functions in Human Inflammatory Skin Diseases.

The skin exerts several fundamental functions that are the first physical, chemical and immune barriers to the human body. Keratinocytes, the main cell type of the epidermis, provide mechanical defense, support skin integrity and actively endorse cutaneous immune responses. Not surprisingly, considering these crucial activities, alterations in keratinocyte functions are associated with different inflammatory skin diseases. Recent findings indicate that the skin should not only be regarded as a target for hormones but that it should also be considered as an endocrine peripheral organ that is directly involved in the synthesis and metabolism of these chemical messengers. Sex hormones have multiple effects on the skin, attributed to the binding with intracellular receptors expressed by different skin cell populations, including keratinocytes, that activate downstream signaling routes that modulate specific cellular functions and activities. This review is aimed at reorganizing the current knowledge on the role exerted by sex hormones on keratinocyte function in five different inflammatory skin diseases: Hidradenitis suppurativa; Acne vulgaris; Atopic dermatitis; progesterone hypersensitivity; psoriasis. The results of our work aim to provide a deeper insight into common cellular mechanisms and molecular effectors that might constitute putative targets to address for the development of specific therapeutic interventions.

Development of a Transdermal Delivery System for Tacrine

Tacrine has several mechanisms of action. The putative primary mechanism of action of tacrine for Alzheimer's disease is reversible inhibition of acetylcholinesterase (AChE), which thus slows the breakdown of the chemical messenger acetylcholine (ACh) in the brain. Tacrine also inhibits butyrylcholinesterase activity. In accumulation, tacrine blocks sodium and potassium channels. Tacrine also acts as a histamine N-methyltransferase inhibitor. This study was carried out to develop matrix based transdermal patches containing Tacrine to overcome the first pass metabolism and to reduce frequency of dosing compared to oral route. . Matrix type of transdermal patches was developed by using Methocel K4M, Methocel K15M, Methocel K100M and Xanthan gum polymers. Transdermal patches were prepared by employing solvent casting method. Drug excipients compatibility studies were carried out by using FTIR, and it was observed that there were no interactions. Formulations were prepared with the varying concentrations polymers ranging from F1-F16, and all the formulations were evaluated for various physical parameters Physical appearance, Flatness, Weight variation, Thickness, Folding endurance, Drug content, Moisture uptake, Moisture content and Swelling study and all the results were found to be within the pharmacopeial limits, invitro drug release studies by using dialysis membrane. Among all the 16 Tacrine transdermal patches formulations F5 formulations which contain Methocel K15M 100 mg had shown 97.61% % cumulative drug release within 12 hours.

Effect of Channel Radius on Fluorescent Nanoparticle Based Molecular Communication

The effect of the communication channel size on the transport and subsequent detection of chemical messengers is investigated on millimetric and micrometric channels. The transport of the information carriers, being characterized by an advective and a diffusive contribution, was simulated by varying the flow velocity and the diffusion coefficient. Then, to evaluate the information quality, the Intersymbol Interference (ISI) between two consecutive signals at a specific release delay was estimated. This allowed us to verify that operating under micrometric channel conditions has a larger flow velocity range to obtain completely separated successive signals and smaller release delays can be used between signals. The theoretical results were confirmed by developing a prototype molecular communication platform operating under microfluidic conditions, which enables communication through fluorescent nanoparticles, namely Carbon Quantum Dots (CQDs).

A Pseudorabies Virus Serine/Threonine Kinase, US3, Promotes Retrograde Transport in Axons via Akt/mToRC1.

ABSTRACTInfection of peripheral axons by alpha herpesviruses (AHVs) is a critical stage in establishing a lifelong infection in the host. Upon entering the cytoplasm of axons, AHV nucleocapsids and associated inner-tegument proteins must engage the cellular retrograde transport machinery to promote the long-distance movement of virion components to the nucleus. The current model outlining this process is incomplete, and further investigation is required to discover all viral and cellular determinants involved as well as the temporality of the events. Using a modified trichamber system, we have discovered a novel role of the pseudorabies virus (PRV) serine/threonine kinase US3 in promoting efficient retrograde transport of nucleocapsids. We discovered that transporting nucleocapsids move at similar velocities in both the presence and absence of a functional US3 kinase; however, fewer nucleocapsids are moving when US3 is absent, and they move for shorter periods of time before stopping, suggesting that US3 is required for efficient nucleocapsid engagement with the retrograde transport machinery. This led to fewer nucleocapsids reaching the cell bodies to produce a productive infection 12 h later. Furthermore, US3 was responsible for the induction of local translation in axons as early as 1 h postinfection (hpi) through the stimulation of a phosphatidylinositol 3-kinase (PI3K)/Akt-mToRC1 pathway. These data describe a novel role for US3 in the induction of local translation in axons during AHV infection, a critical step in transport of nucleocapsids to the cell body.IMPORTANCE Neurons are highly polarized cells with axons that can reach centimeters in length. Communication between axons at the periphery and the distant cell body is a relatively slow process involving the active transport of chemical messengers. There is a need for axons to respond rapidly to extracellular stimuli. Translation of repressed mRNAs present within the axon occurs to enable rapid, localized responses independently of the cell body. AHVs have evolved a way to hijack local translation in the axons to promote their transport to the nucleus. We have determined the cellular mechanism and viral components involved in the induction of axonal translation. The US3 serine/threonine kinase of PRV activates Akt-mToRC1 signaling pathways early during infection to promote axonal translation. When US3 is not present, the number of moving nucleocapsids and their processivity are reduced, suggesting that US3 activity is required for efficient engagement of nucleocapsids with the retrograde transport machinery.

Regulatory role and anticarcinogenic properties of certain vitamins' active derivatives and vitamin-like substances

Vitamins are low-molecular compounds consisting of an essential part of the human diet. After entering the human organism vitamins or their precursors can undergo chemical modification, changing their biological properties and regulatory activity. For many decades, vitamins were considered mainly as precursors of enzyme cofactors, and hypovitaminosis was interpreted as a deficiency of a particular metabolite resulting from enzyme's insufficient activity. However, with the development of molecular biology techniques and breakthrough in understanding of gene expression regulation and cell signaling mechanisms, as well as in molecular mechanisms of diseases associated with impaired functions, it became clear that there are significantly more active forms of vitamins, and their functions in the human body are more diverse than it had been suggested previously. The purpose of this review was to consider vitamins' and vitamins' derivatives regulatory and anti-tumor role and their potential for clinical application as main or adjuvant drugs for malignant neoplasms treatment. Material and methods. The present review is based on the results of literature analysis conducted in the Scopus, PubMed, Science Direct databases for the keywords «vitamin A AND cancer», «retinoids AND cancer», «vitamin D AND cancer», «vitamins AND cancer», «vitamins AND cancer». The search depth was 6 years (2016-2021). Results. Active forms of hydrophilic and lipophilic vitamins are key participants in the processes of chromatin remodeling, genome stability maintaining, covalent modification of proteins, including signaling and regulatory ones, and also act as chemical messengers themselves. Therefore, vitamin deficiency is associated with autoimmune and chronic diseases such as cancer, atherosclerosis, diabetes mellitus, etc. This review considers the regulatory role of active forms of vitamins, their derivatives and vitamin-like substances as well as their involvement in the process of carcinogenesis. Conclusions. Modern studies confirm the high therapeutic potential of vitamins: the use of pharmacological doses of vitamins or their derivatives may help to prevent or fight non-communicable diseases, including cancer.

Comprehensive step-by-step procedure to setup a molecular communication through liquid experiment

Molecular communication allows information to be exchanged in environments where electromagnetic waves are prohibited. It employs the exchange of information particles travelling through fluids. The transmitter releases several chemical messengers inside the communication channel, encoding the message it intends to send in an appropriate way. These messengers will be propagated in the communication channel according to the laws that determine their movement in the environment, until they reach the receiver, which then captures their presence and decodes their content.To set up an experiment of molecular communication through liquid, the following are required:•The simulation of the experiment by means of numerical resolution of the differential equations governing the process, in order to select the proper modulation technique.•The synthesis of the carbon nanoparticles to serve as the information nanoparticles.•The arrangement of the bench prototype for the experiments.

Geoffrey Burnstock 1929–2020

Geoffrey Burnstock was a biomedical scientist who gained renown for his discovery that adenosine 5′-triphosphate (ATP) functions as an extracellular signalling molecule. Born in London and educated at King’s and University Colleges, he did postdoctoral work at Mill Hill and Oxford. He moved in 1959 to the Department of Zoology at the University of Melbourne because he sensed there a greater freedom to challenge established thinking in physiology. His group found that transmission from sympathetic and parasympathetic autonomic nerves to smooth muscle was in some places not mediated by the accepted chemical messengers (noradrenaline and acetylcholine). He amassed evidence that ATP was this non-adrenergic, non-cholinergic (NANC) transmitter, using biochemical, histological and electrophysiological approaches: heretically, he styled this ‘purinergic transmission’. Geoff further upset dogma in the 1970s by proposing ‘co-transmission’ in which some nerves released ATP in addition to either noradrenaline or acetylcholine. He distinguished pharmacologically P1 receptors (activated best by adenosine and blocked by xanthines) and P2 receptors (activated best by purine nucleotides such as ATP) and he proposed in 1985 that the latter embraced P2X (ion channel) and P2Y (G protein-coupled) subtypes: about ten years later these categories were substantiated by cDNA cloning. From 1975 until his retirement in 1997, Geoff was head of Anatomy and Embryology at University College London (UCL), which he developed energetically into a large and strong research department. Later, as head of the Autonomic Research Institute at the Royal Free (part of UCL), he continued to collaborate extensively, and founded several journals and international professional societies. He widely sought clinical benefit for his discoveries, and both P2X and P2Y receptors have been developed as the targets of useful therapeutics (gefapixant, clopidogrel). Geoff was proud of his modest, rather humble, background and eschewed formality. He may have smiled when his early discoveries were met with cynicism, even ridicule (‘pure-imagine’ transmission noted one amusing critic), but this just reinforced his resolve and encouraged his encyclopaedic oeuvre.

Obesity: Overview of a Universal Health Conundrum

Obesity is a worldwide health issue which is displaying increasing prevalence trend. World Health Organisation (WHO) has already given it a epidemic status. Many physiological parameters such as Body Mass Index (BMI), Waist Circumference (WC), Waist to Hip Ratio (WHR) are used for measurement of obesity. This review was written with the aim to give an inclusive picture of current prevalence of obesity along with discussing the physiology and function of different adipocytes and the numerous chemical messengers released by them. The manifold impact of obesity on various body systems can be elucidated by exploring the adipocytes, adipokines its functions and signalling mechanism. The adipokines enlist as key players in numerous systemic diseases. Obesity has a significant pathophysiological role in morbidity and mortality causing conditions globally. Obesity can potentially be the leading reason of economic burden on global health care, adversely impacting the comprehensive quality of life. This review is an effort to provide a better understanding of the current obesity status and emphasise further researches on its diverse aspects.

Recent research trends in voltammetric sensing platforms for hormones and their applications to human serum analyses.

Hormones are essential chemical messengers that modulate body homeostasis and regulate appetite, mood, reproduction, and metabolism in the human body. Its dysregulation in the body can cause diabetes, Alzheimer's disease, and autism. The detection of hormone levels in biological fluids, including serum samples, could facilitate the precaution, diagnosis, and cure of diseases. Voltammetric sensing devices exhibiting significant sensitivity, selectivity, as well as facile, cost-effective fabrication, are one of the promisingmethods for detecting hormone levels. Thus, this review briefly highlights recent advances toward developing voltammetric sensors for a wide spectrum of amino acid-derived, peptide, and lipid-derived hormones alongside their applications to the analyses of human serum samples. Furthermore, several challenging issues and the prospects of voltammetric hormone-sensing devices in clinical diagnostic applications are discussed.

Potent γ-amino butyric acid producing psychobioticLactococcus lactis LP-68 from non-rhizospheric soil of Syzygium cumini (Black plum).

Gamma amino butyric acid (GABA) is a chemical messenger that plays a significant role in muscle relaxation and brain health. Certain lactic acid bacteria (LAB) produce significant levels of GABA and thus act as potential psychobiotic cultures. In the present study, LAB were isolated from non-rhizospheric soil sample of Syzygium cumini (Black plum). A total of 57 LAB were isolated on the basis of their morphological and acid producing characteristic on de Man Rogosa Sharpe (MRS) agar. Only seven isolates were found to produce GABA (0.09-1.13gL-1) in MRS broth and were identified as Lactococcus. However, L. lactis LP-68 produced highest amount of GABA and was selected for further optimization of culture conditions (pH, temperature and MSG) by response surface methodology (RSM). The optimization resulted in approximately four-fold increase in GABA production (4.11gL-1). The results indicate that the L. lactis LP-68 can be used as starter culture for production of GABA-enriched functional foods.

The Active Phytohormone in Microalgae: The Characteristics, Efficient Detection, and Their Adversity Resistance Applications.

Phytohormones are a class of small organic molecules that are widely used in higher plants and microalgae as chemical messengers. Phytohormones play a regulatory role in the physiological metabolism of cells, including promoting cell division, increasing stress tolerance, and improving photosynthetic efficiency, and thereby increasing biomass, oil, chlorophyll, and protein content. However, traditional abiotic stress methods for inducing the accumulation of energy storage substances in microalgae, such as high light intensity, high salinity, and heavy metals, will affect the growth of microalgae and will ultimately limit the efficient accumulation of energy storage substances. Therefore, the addition of phytohormones not only helps to reduce production costs but also improves the efficiency of biofuel utilization. However, accurate and sensitive phytohormones determination and analytical methods are the basis for plant hormone research. In this study, the characteristics of phytohormones in microalgae and research progress for regulating the accumulation of energy storage substances in microalgae by exogenous phytohormones, combined with abiotic stress conditions at home and abroad, are summarized. The possible metabolic mechanism of phytohormones in microalgae is discussed, and possible future research directions are put forward, which provide a theoretical basis for the application of phytohormones in microalgae.

Sociability as a personality trait in animals: methods, causes and consequences.

Within animal populations there is variation among individuals in their tendency to be social, where more sociable individuals associate more with other individuals. Consistent inter-individual variation in 'sociability' is considered one of the major axes of personality variation in animals along with aggressiveness, activity, exploration and boldness. Not only is variation in sociability important in terms of animal personalities, but it holds particular significance for, and can be informed by, two other topics of major interest: social networks and collective behaviour. Further, knowledge of what generates inter-individual variation in social behaviour also holds applied implications, such as understanding disorders of social behaviour in humans. In turn, research using non-human animals in the genetics, neuroscience and physiology of these disorders can inform our understanding of sociability. For the first time, this review brings together insights across these areas of research, across animal taxa from primates to invertebrates, and across studies from both the laboratory and field. We show there are mixed results in whether and how sociability correlates with other major behavioural traits. Whether and in what direction these correlations are observed may differ with individual traits such as sex and body condition, as well as ecological conditions. A large body of evidence provides the proximate mechanisms for why individuals vary in their social tendency. Evidence exists for the importance of genes and their expression, chemical messengers, social interactions and the environment in determining an individual's social tendency, although the specifics vary with species and other variables such as age, and interactions amongst these proximate factors. Less well understood is how evolution can maintain consistent variation in social tendencies within populations. Shifts in the benefits and costs of social tendencies over time, as well as the social niche hypothesis, are currently the best supported theories for how variation in sociability can evolve and be maintained in populations. Increased exposure to infectious diseases is the best documented cost of a greater social tendency, and benefits include greater access to socially transmitted information. We also highlight that direct evidence for more sociable individuals being safer from predators is lacking. Variation in sociability is likely to have broad ecological consequences, but beyond its importance in the spread of infectious diseases, direct evidence is limited to a few examples related to dispersal and invasive species biology. Overall, our knowledge of inter-individual variation in sociability is highly skewed towards the proximate mechanisms. Our review also demonstrates, however, that considering research from social networks and collective behaviour greatly enriches our understanding of sociability, highlighting the need for greater integration of these approaches into future animal personality research to address the imbalance in our understanding of sociability as a personality trait.

A Brief Analysis About the Drug Addiction by Youths in India

Abstract: People have been taking the drug in various forms for many years for enjoyment, relaxation, sleeping, stimulation, or another reason. In the starting, people takes the drug for taste and alter the consciousness, behavior, mood, and thoughts but he/she becomes habitual and dependent on any substance use disorder such as alcohol, tobacco, cannabis, ecstasy, cocaine, methamphetamine, and heroin, amphetamines, or illegal drugs. As per my thoughts and watching surroundings, if you ask a drug intake person “how do you become a drug addictive”? Most people will answer this “they started taking the drug in their friend circle, at relatives home or with relationship partner”. The first time they take it for taste or due to forcing by someone but after some time this becomes a habit. Peer pressure can fall you in this black world. Also, if someone has family history of addiction then he/she may chance to catch this addiction and make habitual others as well. So good friend circle really matters. Drugs such as heroin and marijuana are structured in the same way as chemical messengers known as neurotransmitters. These neurotransmitters are produced naturally by the human brain. As a result of this similarity, the drugs can fool the receptors of human brain and activate the nerve cells in such a way that they send some abnormal messages. In case of drugs like methamphetamine and cocaine, the nerve cells get activated and they release extraordinarily large volumes of neurotransmitters. They are also capable of preventing the brain from recycling these chemicals in a normal manner. A normal level of production is necessary in order to end the signal between neurons. Keywords: Alcohol – Beer, Wine, & Liquor, Opioids – Heroin, Fentanyl & Oxycodone, Cannabinoids – Marijuana & Hashish, Benzodiazepines – Ativan, Valium & Xanax, Stimulants – Adderall, Cocaine & Meth.