Innervation Patterns of Autonomic Axons in the Human Endocrine Pancreas

Rodriguez-Diaz, Rayner,Abdulreda, Midhat ,H.,Formoso, Alexander ,L.,Gans, Itai,Ricordi, Camillo,Berggren, Per-Olof,Caicedo, Alejandro Elsevier 2011 Cell metabolism Vol.14 No.1

<P><B>Summary</B></P><P>The autonomic nervous system regulates hormone secretion from the endocrine pancreas, the islets of Langerhans, thus impacting glucose metabolism. The parasympathetic and sympathetic nerves innervate the pancreatic islet, but the precise innervation patterns are unknown, particularly in human. Here we demonstrate that the innervation of human islets is different from that of mouse islets and does not conform to existing models of autonomic control of islet function. By visualizing axons in three dimensions and quantifying axonal densities and contacts within pancreatic islets, we found that, unlike mouse endocrine cells, human endocrine cells are sparsely contacted by autonomic axons. Few parasympathetic cholinergic axons penetrate the human islet, and the invading sympathetic fibers preferentially innervate smooth muscle cells of blood vessels located within the islet. Thus, rather than modulating endocrine cell function directly, sympathetic nerves may regulate hormone secretion in human islets by controlling local blood flow or by acting on islet regions located downstream.</P> <P><B>Highlights</B></P><P>► Detailed quantitative analysis of the innervation of mouse and human islets ► Human endocrine cells are sparsely innervated ► Sympathetic axons innervate vascular smooth muscle cells deep inside human islets ► Autonomic control of human islets may use unique mechanisms</P>

Real-time detection of acetylcholine release from the human endocrine pancreas

Rodriguez-Diaz, Rayner,Dando, Robin,Huang, Y Anthony,Berggren, Per-Olof,Roper, Stephen D,Caicedo, Alejandro Nature Publishing Group, a division of Macmillan P 2012 Nature protocols Vol.7 No.6

Neurons, sensory cells and endocrine cells secrete neurotransmitters and hormones to communicate with other cells and to coordinate organ and system function. Validation that a substance is used as an extracellular signaling molecule by a given cell requires a direct demonstration of its secretion. In this protocol we describe the use of biosensor cells to detect neurotransmitter release from endocrine cells in real-time. Chinese hamster ovary cells expressing the muscarinic acetylcholine (ACh) receptor M3 were used as ACh biosensors to record ACh release from human pancreatic islets. We show how ACh biosensors loaded with the Ca<SUP>2+</SUP> indicator Fura-2 and pressed against isolated human pancreatic islets allow the detection of ACh release. The biosensor approach is simple; the Ca<SUP>2+</SUP> signal generated in the biosensor cell reflects the presence (release) of a neurotransmitter. The technique is versatile because biosensor cells expressing a variety of receptors can be used in many applications. The protocol takes ?? h.

Dynamic Manipulation of an Unknown Object Under Compliant Non-holonomic Constraints

Rodolfo Garcia-Rodriguez,Vicente Parra-Vega,Luis Pantoja-Garcia,Ernesto Olguin-Diaz 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.6

There are many robot control schemes where the end-effector is subject to holonomic or non-holonomic constraints. However, the literature has overlooked the problem of simultaneous holonomic and nonholonomic constraints. In particular, the case of constrained tangent force with a normal force to manipulate an object. In this paper, to study this problem, it is considered two 2D rigid robot fingers whose end-effectors are equipped with hemispherical deformable tips in contact with a rigid object. If the radius changes when force is exerted, we can notice a 1D-tangent constraint force and a 1D-normal compliant force arise simultaneously from the so-called compliant nonholonomic constraint. An energy reshaping controller is proposed to ensure simultaneously the convergence of the normal and tangential constraint forces assuming nonlinear viscoelastic damping. A representative simulation study shows the advantages of the constraints forces, in complex dexterity tasks, under the assumption that knowledge of the non-regular object is unknown.

Evaluation of reference genes for qRT-PCR studies in the colchicine producing Gloriosa superba L.

Johnson Nekha,Rodriguez Diaz Diana,Ganapathy Sivakumar,Bass John S.,Kutchan Toni M.,Khan Abdul L.,Flavier Albert B. 한국식물생명공학회 2023 Plant biotechnology reports Vol.17 No.4

The flame lily, Gloriosa superba L., is one of the two primary sources of the anti-inflammatory drug, colchicine. Previous studies have shown that a higher level of colchicine production occurs in the rhizomes than in leaves and roots. Earlier precursor feeding and transcriptome analysis of G. superba have provided a putative pathway and candidate genes involved in colchicine biosynthesis. Comparative analysis of expression levels of candidate pathway genes in different tissues of G. superba using quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) can reveal highly expressed genes in the rhizome compared to other tissues which could suggest roles of the gene products in colchicine biosynthesis. Normalization is an important step in effectively analyzing differential gene expression by qRT-PCR with broader applications. The current study selected candidate reference genes from the transcriptome datasets and analyzed them to determine the most stable genes for normalization of colchicine biosynthesis-related genes. Using RefFinder, one stable reference gene, UBC22, was selected to normalize gene expression levels of candidate methyltransferase (MT) genes in the leaves, roots, and rhizomes of G. superba. With UBC22 as reference gene, the methyltransferases, GsOMT1, GsOMT3, and GsOMT4 showed significantly higher expression levels in the rhizome of G. superba, while MT31794 was more highly expressed in the roots. In conclusion, the current results showed a viable reference gene expression analysis system that could help elucidate colchicine biosynthesis and its exploitation for increased production of the drug in G. superba.

Intraoperative pulmonary embolism in shoulder arthroscopy in a patient with previous SARS-CoV-2 infection: a case report

Alejandro Holgado-Rodriguez de,Alberto Izquierdo-Fernandez,Jesus Manuel Mendez-Sanchez,Jose Carlos Diaz-Minarro 대한견주관절의학회 2022 대한견주관절의학회지 Vol.25 No.3

The objective of this article is to describe intraoperative pulmonary embolism during shoulder arthroscopy in a patient with previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Further, we describe how the pandemic has influenced the population by increasing the rate of embolisms. Awareness of such cases will help to increase knowledge regarding SARS-Cov-2 and to determine if such patients should receive routine antithrombotic prophylaxis.

Four Keys to Chilean Culture : Authoritarianism, Legalism, Fatalism and Compadrazgo

Carlos F. Gomez Diaz(까를로스 고메스 디아스),Jenny K. Rodriguez Ortiz(제니 로드리게스 오르띠스) 한국라틴아메리카학회 2006 라틴아메리카연구 Vol.19 No.3

In this paper, the authors explore some of the characteristics that stand out in social dynamics in Chile and which can be understood as structuring ‘Chilean culture’, particularly amongst the population in the middle region on the country, between the Fourth and the Tenth Region; that is to say between La Serena and the Great Isle of Chiloe?. The paper comprises six sections. The first section provides a brief introduction to Chilean culture, contextualising it in the framework of the Latin American Region. The second section discusses paternalistic authoritarianism in social relations; the third section addresses legalism, arguing that in Chile, legalism implies a tendency to generate formal mechanisms to avoid uncertainty and accountability regarding the consequences of decisions; the fourth section discusses the tendency towards fatalism and conservatism and these traits coexist with double discourse; the fifth section discusses the construction of social dynamics, focusing on the influence of nepotism, friendship and compadrazgo in relational patterns. Finally, the sixth section provides a final reflection of how the traits and characteristics described frame what could be understood as ‘Chilean culture’ and result in particular dynamics within Chilean society.

Donor Islet Endothelial Cells in Pancreatic Islet Revascularization

Nyqvist, Daniel,Speier, Stephan,Rodriguez-Diaz, Rayner,Molano, R. Damaris,Lipovsek, Saš,a,Rupnik, Marjan,Dicker, Andrea,Ilegems, Erwin,Zahr-Akrawi, Elsie,Molina, Judith,Lopez-Cabeza, Maite,Villat American Diabetes Association 2011 Diabetes Vol.60 No.10

<P><B>OBJECTIVE</B></P><P>Freshly isolated pancreatic islets contain, in contrast to cultured islets, intraislet endothelial cells (ECs), which can contribute to the formation of functional blood vessels after transplantation. We have characterized how donor islet endothelial cells (DIECs) may contribute to the revascularization rate, vascular density, and endocrine graft function after transplantation of freshly isolated and cultured islets.</P><P><B>RESEARCH DESIGN AND METHODS</B></P><P>Freshly isolated and cultured islets were transplanted under the kidney capsule and into the anterior chamber of the eye. Intravital laser scanning microscopy was used to monitor the revascularization process and DIECs in intact grafts. The grafts’ metabolic function was examined by reversal of diabetes, and the ultrastructural morphology by transmission electron microscopy.</P><P><B>RESULTS</B></P><P>DIECs significantly contributed to the vasculature of fresh islet grafts, assessed up to 5 months after transplantation, but were hardly detected in cultured islet grafts. Early participation of DIECs in the revascularization process correlated with a higher revascularization rate of freshly isolated islets compared with cultured islets. However, after complete revascularization, the vascular density was similar in the two groups, and host ECs gained morphological features resembling the endogenous islet vasculature. Surprisingly, grafts originating from cultured islets reversed diabetes more rapidly than those originating from fresh islets.</P><P><B>CONCLUSIONS</B></P><P>In summary, DIECs contributed to the revascularization of fresh, but not cultured, islets by participating in early processes of vessel formation and persisting in the vasculature over long periods of time. However, the DIECs did not increase the vascular density or improve the endocrine function of the grafts.</P>

e-Business (2) ; Tacit and Formal Knowledge and Learning in Small Business : An Exploratory Study on the Perceptions of Successful Businessmen

Luiz Carlos De SA Carvalho,Monica Esteves Rodriguez,Benito Diaz Paret 한국경영정보학회 2005 한국경영정보학회 학술대회논문집 Vol.2005 No.-

Oral findings and its association with prenatal and perinatal factors in newborns

Perez-Aguirre, Brenda,Soto-Barreras, Uriel,Loyola-Rodriguez, Juan Pablo,Reyes-Macias, Juan Francisco,Santos-Diaz, Miguel Angel,Loyola-Leyva, Alejandra,Garcia-Cortes, Obed The Korean Pediatric Society 2018 Clinical and Experimental Pediatrics (CEP) Vol.61 No.9

Purpose: This study aimed to determine the frequency of abnormalities in the newborn oral cavity and to evaluate the association with prenatal and perinatal factors. Methods: This cross-sectional study evaluated 2,216 newborns. Oral findings were assessed in the first 24 hours of life using visual examination. Sex, weight, length, gestational age, and medical disorders at birth were recorded. Maternal demographic and medical information was also obtained. Results: The most common oral findings were Bohn's nodules, Epstein's pearls, and dental lamina cysts. Other intraoral findings included odontogenic cysts, ankyloglossia, and natal teeth, among others. In logistic regression analyses, folic acid consumption during pregnancy was significantly associated with Bohn's nodules (odds ratio [OR], 1.79; 95% confidence interval [CI], 1.23-2.55; P=0.002), Epstein's pearls (OR, 1.63; 95% CI, 1.14-2.33; P=0.007), and dental lamina cysts (OR, 1.45; 95% CI, 1.02-2.05; P=0.038). Moreover, preterm births were negatively associated with prevalence of Bohn's nodules (OR, 0.63; 95% CI, 0.50-0.80; $P{\leq}0.0001$). Comparison between newborns with and without oral inclusion cysts showed that maternal folic acid and iron intake were significantly different (P<0.05). Conclusion: Maternal folic acid and iron intake were associated with the prevalence of oral inclusion cysts.

End-effector positioning due to joint clearances: A comparison among three planar 2-DOF parallel manipulators

Héctor F. Quintero,Luz A. Mejia,Miguel Diaz-Rodriguez 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.7

This paper develops a model for studying the effect of joint clearances on the end-effector's loci for planar parallel manipulators with 2 degree-of-freedom (DOF). The condition for developing end-effector loci equations with respect to the joint clearance relies on the fact that at least one point of contact is always presented in each joints. The motivation of this work lies in the fact that the proposed procedure allows the study of parallel manipulators that can be considered as design concepts for developing an x-y cutting table for a textile industry. Numerical simulations enable to compare three 2-DOF planar parallel manipulators architectures: i) 2-RRR, ii) 2-RPR, and iii) 2-RPR. A Monte Carlo simulation allows us to find the area of possible end-effector locations for a specific value of clearance. Also, the equations allow us to find the largest distance from the desired location to the one obtained considering clearance. Findings shed some lights on establishing which parallel manipulator is less affected to joint clearance.