Ghrelin Stimulates Porcine Somatotropes

Ghrelin is an endogenous ligand for growth hormone secretagogue receptor (GHS-R) and is predominantly produced by the stomach and lower amounts in the hypothalamus and various peripheral tissues. Ghrelin is a potent stimulator of growth hormone (GH) secretion from the pituitary in vivo and in vitro. GH secretion from the pituitary also is controlled by two hypothalamic peptides: stimulatory GH-releasing hormone (GHRH) and inhibitory somatostatin-14 (SRIH). GH participates in its own rhythmic secretion through feedback action on GHRH and SRIH neurons. The mechanism of action of GHS is not established. The present study examined the signal transduction pathways of ghrelin in isolated porcine somatotropes. The ability of ghrelin to induce an increase in the intracellular Ca2+ concentration – [Ca2+]i – somatotropes was examined in dispersed porcine pituitary cells using a calcium imaging system. Somatotropes were functionally identified by application of human growth hormone releasing hormone (hGHRH). Ghrelin increased the [Ca2+]i in a dose-dependent manner in 98% of the cells that responded to. In the presence of (D-Lys3)-GHRP-6, a specific receptor antagonist of GHS-R, the increase in [Ca2+]i evoked by ghrelin was decreased. Pretreatment of cultures with somatostatin or neuropeptide Y reduced the ghrelin-induced increase of [Ca2+]i. The stimulatory effect of ghrelin on somatotropes was greatly attenuated in lowcalcium saline and blocked by nifedipine, an L-type calcium channel blocker, suggesting involvement of calcium channels. In a zero Na+ solution, the stimulatory effect of ghrelin on somatotropes was decreased, suggesting that besides calcium channels, sodium channels are also involved in ghrelin-induced calcium transients. Either SQ-22536, an adenylyl cyclase inhibitor, or U73122, a phospholipase C inhibitor, decreased the stimulatory effects of ghrelin on [Ca2+]i transiently, indicating the involvement of adenylyl cyclase-cyclic adenosine monophosphate and phospholipase C inositol 1,4,5-trisphosphate pathways. The non-peptidyl GHS, L-692,585 (L-585), induced changes in [Ca2+]i similar to those observed with ghrelin. Application of L-585 after ghrelin did not have additive effects on [Ca2+]i. Preapplication of L-585 blocked the stimulatory effect of ghrelin on somatotropes. Our results suggest that the actions of ghrelin and synthetic GHS closely parallel each other, in a manner that is consistent with an increase of hormone secretion. An understanding of the molecular mechanisms by which ghrelin and GHS modulate GH secretion is of particular interest in the regulation of GH for muscle accretion and somatic growth

Subpopulations of Chicken Somatotropes with Differing Intracellular Calcium Concentrations Responses to Secretagogues

Multiple secretagogues stimulate the release of growth hormone (GH). The present studies examined the ability of chicken somatotropes to respond to GH secretagogues with increased intracellular calcium concentrations ([Ca 2+ ]i ). It was hypothesized that there are subsets of the somatotrope population with different responsiveness to the various secretagogues. Avian somatotropes were identified and distinguished from other anterior pituitary cells, by their unique ability to respond to GH-releasing hormone with increased [Ca 2+ ]i with immunocytochemistry used as a post-hoc confirmatory test. Large increases in [Ca 2+ ]i (222 ± 16 nm) were evoked by thyrotropin-releasing hormone in only 73% of the somatotropes. Similarly, [Ca 2+ ]i was increased by perifusion with pituitary adenylate cyclase-activating peptide in 85% and by leptin but only in 51% of somatotropes. Ghrelin acutely increased [Ca 2+ ]i in only 21% of somatotropes. Perfusion with gonadotropinreleasing hormone elevated [Ca 2+ ]i , but in only 40% of somatotropes. The kinetics of calcium transients and the magnitude of the response differed from those observed in the presumptive gonadotropes. It is concluded that there are subsets of the somatotrope population in the anterior pituitary gland with differences in their ability to respond to various secretagogue

Značaj prostornog rasporeda u proizvodnom procesu

In engineering design, the problem of layout has a special significance and has been the object of research for many years. There are two groups of problems: the problem of location and the problem of the distribution of elements. In the domain of industry, the location problem is related to determining the most favorable location (production complex) on the macro plan. When analyzing the problem of the distribution of elements, it is first of all necessary to have an insight into the set of potential surfaces that some elements may require within an analyzed system. In order to explain the importance of the spatial configuration and the objectives of its introduction, it is necessary to describe the existing configuration of the line for the production of nougats, to illustrate the flow of materials, the configuration and the degree of automation. Increasing the degree of automation of production lines can only have advantages because it increases the quality of the finished product, shortens the production cycle and therefore increases productivity.U inženjerskom projektovanju, problem prostornog rasporeda ima poseban značaj i predmet je istraživanja dugi niz godina. Tu su prisutne dve grupe problema: problem lokacije i problem raspodele elemenata. U domenu industrije problem lokacije je vezan za određivanje najpovoljnijeg mesta (proizvodnog kompleksa) na makro planu. Kada se analizira problem raspodele elemenata, potrebno je pre svega imati uvid u skup potencijalnih površina koje pojedini elementi mogu da zahtevaju u okviru nekog analiziranog sistema. Kako bi se objasnio značaj prostornog rasporeda i ciljevi njegovog uvođenja, potrebno je opisati postojeće konfiguracije linije odabranog proizvoda, na njima prikazati tok materijala, prostorni raspored i stepen automatizacije. Povećanje stepena automatizacije proizvodnih linija može imati samo prednosti, jer se povećava kvalitet gotovog proizvoda, skraćuje proizvodni ciklus i time povećava proizvodnost

Konvolucijske neuronske mreže - primena u preciznoj poljoprivredi

A promising concept of artificial intelligence that records intense developments in the field of digital imaging is Deep Learning (DL). More intensive research within this field has been recorded over the past two decades, and has been applied in the agricultural industry as well. This paper will describe the DL technology which represents a part of Machine Learning (ML), based on Convolutional Neural Networks (CNN). It takes a special application in a machine vision where it allows machines to learn from experience, adapt to new technologies, and perform human tasks. Input data can be from a variety of sources: from classic digital camera shots to satellite images, as well as from recordings obtained by means of hyperspectral, thermal and infrared cameras. The increasing popularity and use of trunks in agricultural fields is increasing, and the very application of these new technologies leads to the huge amount of data that needs to be processed in real time, therefore, DL algorithms are increasingly used. The paper will summarize the current and considered possible applications of CNN in primary and precise agriculture in the future.Obećavajući koncept veštačke inteligencije koji beleži intenzivan razvoj u oblasti digitalne obrade slike je duboko učenje (Deep Learning – DL). Intenzivnije istraživanje u okviru ove oblasti beleži se poslednje dve decenije, a primenu poprima i u poljoprivrednoj industiji. U okviru ovog radu opisana je tehnologija DL koja predstavlja deo mašinskog učenja (Machine Learning – ML), bazirajući se na konvolucijske neuralne mreže (Convolution Neural Networks – CNN). Posebnu primenu zauzima u mašinskoj viziji gde omogućava mašinama da uče iz iskustva, prilagođavaju se novim tehnologijama i obavljaju ljudske zadatke. Ulazni podaci mogu biti iz raznovrsnih izvora: od klasičnih digitalnih snimaka kamere do satelitskih snimaka, kao i snimaka dobijenih pomoću hiperspektralnih, termalnih i infrared kamera. Sve je veća popularnost i upotreba dronova na poljoprivrednim površinama, a samom primenom ovih novih tehnologija dolazi se do ogromnog broja podataka koje je potrebno obraditi u realnom vremenu, stoga se i algoritmi DL sve više upotrebljavaju. U radu su prikazane dosadašnje primene CNN u primarnoj i preciznoj poljoprivredi kao i moguće primene DL u budućnosti

Promotion of Color Sorting in Industrial Systems Using a Deep Learning Algorithm

Color sorting is a technological operation performed with the aim of classifying compliant and noncompliant agricultural products in large-capacity industrial systems for agricultural product processing. This paper investigates the application of the YOLOv3 algorithm on raspberry images as a method developed for the detection, localization, and classification of objects based on convolutional neural networks (CNNs). To our knowledge, this is the first time a YOLO algorithm or CNN has been used with original images from the color sorter to focus on agricultural products. Results of the F1 measure were in the 92–97% range. Images in full resolution, 1024 × 1024, produced an average detection time of 0.37 s. The impact of the hyperparameters that define the YOLOv3 model as well as the impact of the application of the chosen augmentative methods on the model are evaluated. The successful classification of stalks, which is particularly challenging due to their shape, small dimensions, and variations, was achieved. The presented model demonstrates the ability to classify noncompliant products into four classes, some of which are appropriate for reprocessing. The software, including a graphic interface that enables the real-time testing of machine learning algorithm, is developed and presented

Međusobni uticaj različitih parametara pri monitoringu prinosa

en measuring and analyzing site-specific yield known as the yield monitoring within a wider cycle of precise agriculture, about 30 parameters are measured from inertia for mapping yields. The most important parameters with the default three parameters that define the location (latitude, longitude and elevation) are mass grain yield and grain moisture. In addition to this data during the yield monitoring, the temperature of the grain, speed of the combine and delution of precision (DOP) were also observed in this paper. By simple statistical testing of the correlation between these parameters, the level of mutual influence was determined, among other things, the degree of influence of all mentioned and observed parameters on yield, in response to the research question whether the yield affects another parameter other than the location and physical and chemical properties of the land at that location . A different degree of influence was determined, but no significant additional impact on the yield was calculated by measuring and measuring the measurement itself. For the monitoring of the yield of seed wheat harvesting on the "Mladost" PKB, Tabla 2, the Class Lexion 450 harvester with an upgraded system for monitoring the AGL Technology manufacturer was used. For the statistical analysis, the parametric method of correlation within the software package SPSS Statistics v.21 was used.Pri merenju i analizi lokacijski specifičnog prinosa poznatijeg kao monitoring prinosa u okviru šireg ciklusa precizne poljoprivrede meri se oko 30 parametara od interesa za mapiranje prinosa i šire. Najvažniji parametri uz podrazumevana tri parametra koja definišu lokaciju (latituda, longituda i elevacija) su maseni prinos zrna i vlažnost zrna. Uz ove podatke tokom monitoringa prinosa u ovom radu posmatrani su i temperatura zrna, brzina kretanja kombajna i odstupanje preciznosti lociranja (DOP). Jednostavnim statističkim testiranjem korelacije između ovih parametara utvrđen je nivo međusobnog uticaja, između ostalog i stepen uticaja svih navedenih i posmatranih parametara na prinos, kao odgovor na istraživačko pitanje da li na prinos utiče još neki parametar osim lokacije i fizičko-hemijskih osobina zemljišta na toj lokaciji. Utvrđen je različit stepen uticajnosti, ali nije otkriven ni jedan značajan dodatni uticaj na prinos izračunat posredstvom merenja i makon samog merenja. Za monitoring prinosa pri žetvi semenske pšenice na imanju „Mladost“ PKB, Tabla 2, korišćen je kombajn Class Lexion 450 sa nadograđenim sistemom za monitoring AGL Technology proizvođača. Za statističku analizu korišćena je parametarska metoda korelacije u okviru softverskog paketa SPSS Statistics v.21

Subpopulations of Chicken Somatotropes with Differing Intracellular Calcium Concentrations Responses to Secretagogues

Multiple secretagogues stimulate the release of growth hormone (GH). The present studies examined the ability of chicken somatotropes to respond to GH secretagogues with increased intracellular calcium concentrations ([Ca 2+ ]i ). It was hypothesized that there are subsets of the somatotrope population with different responsiveness to the various secretagogues. Avian somatotropes were identified and distinguished from other anterior pituitary cells, by their unique ability to respond to GH-releasing hormone with increased [Ca 2+ ]i with immunocytochemistry used as a post-hoc confirmatory test. Large increases in [Ca 2+ ]i (222 ± 16 nm) were evoked by thyrotropin-releasing hormone in only 73% of the somatotropes. Similarly, [Ca 2+ ]i was increased by perifusion with pituitary adenylate cyclase-activating peptide in 85% and by leptin but only in 51% of somatotropes. Ghrelin acutely increased [Ca 2+ ]i in only 21% of somatotropes. Perfusion with gonadotropinreleasing hormone elevated [Ca 2+ ]i , but in only 40% of somatotropes. The kinetics of calcium transients and the magnitude of the response differed from those observed in the presumptive gonadotropes. It is concluded that there are subsets of the somatotrope population in the anterior pituitary gland with differences in their ability to respond to various secretagogues</p

Ghrelin Stimulates Porcine Somatotropes

Ghrelin is an endogenous ligand for growth hormone secretagogue receptor (GHS-R) and is predominantly produced by the stomach and lower amounts in the hypothalamus and various peripheral tissues. Ghrelin is a potent stimulator of growth hormone (GH) secretion from the pituitary in vivo and in vitro. GH secretion from the pituitary also is controlled by two hypothalamic peptides: stimulatory GH-releasing hormone (GHRH) and inhibitory somatostatin-14 (SRIH). GH participates in its own rhythmic secretion through feedback action on GHRH and SRIH neurons. The mechanism of action of GHS is not established. The present study examined the signal transduction pathways of ghrelin in isolated porcine somatotropes. The ability of ghrelin to induce an increase in the intracellular Ca2+ concentration – [Ca2+]i – somatotropes was examined in dispersed porcine pituitary cells using a calcium imaging system. Somatotropes were functionally identified by application of human growth hormone releasing hormone (hGHRH). Ghrelin increased the [Ca2+]i in a dose-dependent manner in 98% of the cells that responded to. In the presence of (D-Lys3)-GHRP-6, a specific receptor antagonist of GHS-R, the increase in [Ca2+]i evoked by ghrelin was decreased. Pretreatment of cultures with somatostatin or neuropeptide Y reduced the ghrelin-induced increase of [Ca2+]i. The stimulatory effect of ghrelin on somatotropes was greatly attenuated in lowcalcium saline and blocked by nifedipine, an L-type calcium channel blocker, suggesting involvement of calcium channels. In a zero Na+ solution, the stimulatory effect of ghrelin on somatotropes was decreased, suggesting that besides calcium channels, sodium channels are also involved in ghrelin-induced calcium transients. Either SQ-22536, an adenylyl cyclase inhibitor, or U73122, a phospholipase C inhibitor, decreased the stimulatory effects of ghrelin on [Ca2+]i transiently, indicating the involvement of adenylyl cyclase-cyclic adenosine monophosphate and phospholipase C inositol 1,4,5-trisphosphate pathways. The non-peptidyl GHS, L-692,585 (L-585), induced changes in [Ca2+]i similar to those observed with ghrelin. Application of L-585 after ghrelin did not have additive effects on [Ca2+]i. Preapplication of L-585 blocked the stimulatory effect of ghrelin on somatotropes. Our results suggest that the actions of ghrelin and synthetic GHS closely parallel each other, in a manner that is consistent with an increase of hormone secretion. An understanding of the molecular mechanisms by which ghrelin and GHS modulate GH secretion is of particular interest in the regulation of GH for muscle accretion and somatic growth.</p

Acute death of astrocytes in blast-exposed rat organotypic hippocampal slice cultures.

Blast traumatic brain injury (bTBI) affects civilians, soldiers, and veterans worldwide and presents significant health concerns. The mechanisms of neurodegeneration following bTBI remain elusive and current therapies are largely ineffective. It is important to better characterize blast-evoked cellular changes and underlying mechanisms in order to develop more effective therapies. In the present study, our group utilized rat organotypic hippocampal slice cultures (OHCs) as an in vitro system to model bTBI. OHCs were exposed to either 138 ± 22 kPa (low) or 273 ± 23 kPa (high) overpressures using an open-ended helium-driven shock tube, or were assigned to sham control group. At 2 hours (h) following injury, we have characterized the astrocytic response to a blast overpressure. Immunostaining against the astrocytic marker glial fibrillary acidic protein (GFAP) revealed acute shearing and morphological changes in astrocytes, including clasmatodendrosis. Moreover, overlap of GFAP immunostaining and propidium iodide (PI) indicated astrocytic death. Quantification of the number of dead astrocytes per counting area in the hippocampal cornu Ammonis 1 region (CA1), demonstrated a significant increase in dead astrocytes in the low- and high-blast, compared to sham control OHCs. However only a small number of GFAP-expressing astrocytes were co-labeled with the apoptotic marker Annexin V, suggesting necrosis as the primary type of cell death in the acute phase following blast exposure. Moreover, western blot analyses revealed calpain mediated breakdown of GFAP. The dextran exclusion additionally indicated membrane disruption as a potential mechanism of acute astrocytic death. Furthermore, although blast exposure did not evoke significant changes in glutamate transporter 1 (GLT-1) expression, loss of GLT-1-expressing astrocytes suggests dysregulation of glutamate uptake following injury. Our data illustrate the profound effect of blast overpressure on astrocytes in OHCs at 2 h following injury and suggest increased calpain activity and membrane disruption as potential underlying mechanisms

Exuberant accessory mitral valve tissue with possible true parachute mitral valve: a case report

<p>Abstract</p> <p>Introduction</p> <p>A parachute mitral valve is defined as a unifocal attachment of mitral valve chordae tendineae independent of the number of papillary muscles. Data from the literature suggests that the valve can be distinguished on the basis of morphological features as either a parachute-like asymmetrical mitral valve or a true parachute mitral valve. A parachute-like asymmetrical mitral valve has two papillary muscles; one is elongated and located higher in the left ventricle. A true parachute mitral valve has a single papillary muscle that receives all chordae, as was present in our patient. Patients with parachute mitral valves during childhood have multilevel left-side heart obstructions, with poor outcomes without operative treatment. The finding of a parachute mitral valve in an adult patient is extremely rare, especially as an isolated lesion. In adults, the unifocal attachment of the chordae results in a slightly restricted valve opening and, more frequently, valvular regurgitation.</p> <p>Case presentation</p> <p>A 40-year-old Caucasian female patient was admitted to a primary care physician due to her recent symptoms of heart palpitation and chest discomfort on effort. Transthoracic echocardiography showed chordae tendineae which were elongated and formed an unusual net shape penetrating into left ventricle cavity. The parasternal short axis view of her left ventricle showed a single papillary muscle positioned on one side in the posteromedial commissure receiving all chordae. Her mitral valve orifice was slightly eccentric and the chordae were converting into a single papillary muscle. Mitral regurgitation was present and it was graded as moderate to severe. Her left atrium was enlarged. There were no signs of mitral stenosis or a subvalvular ring. She did not have a bicuspid aortic valve or coarctation of the ascending aorta. The dimensions and systolic function of her left ventricle were normal. Our patient had a normal body habitus, without signs of heart failure. Her functional status was graded as class I according to the New York Heart Association grading.</p> <p>Conclusions</p> <p>A recently published review found that, in the last several decades, there have been only nine adult patients with parachute mitral valve disease reported, of which five had the same morphological characteristics as our patient. This case presentation should encourage doctors, especially those involved in echocardiography, to contribute their own experience, knowledge and research in parachute mitral valve disease to enrich statistical and epidemiologic databases and aid clinicians in getting acquainted with this rare disease.</p