scholarly journals The Developmental Neurotoxicity of Tobacco Smoke Can Be Mimicked by a Combination of Nicotine and Benzo[a]Pyrene: Effects on Cholinergic and Serotonergic Systems

2018 ◽  
Vol 167 (1) ◽  
pp. 293-304 ◽  
Author(s):  
Theodore A Slotkin ◽  
Samantha Skavicus ◽  
Ashley Ko ◽  
Edward D Levin ◽  
Frederic J Seidler
Keyword(s):  
Tobacco Smoke ◽  
Combined Treatment ◽  
Brain Regions ◽  
Developmental Neurotoxicity ◽  
Pregnant Rats ◽  
Relative Safety ◽  
Individual Effects ◽  
Polycyclic Aromatic ◽  
The Individual ◽  
5Ht Receptors

Abstract Tobacco smoke contains polycyclic aromatic hydrocarbons (PAHs) in addition to nicotine. We compared the developmental neurotoxicity of nicotine to that of the PAH archetype, benzo[a]pyrene (BaP), and also evaluated the effects of combined exposure to assess whether PAHs might exacerbate the adverse effects of nicotine. Pregnant rats were treated preconception through the first postnatal week, modeling nicotine concentrations in smokers and a low BaP dose devoid of systemic effects. We conducted evaluations of acetylcholine (ACh) and serotonin (5-hydroxytryptamine, 5HT) systems in brain regions from adolescence through full adulthood. Nicotine or BaP alone impaired indices of ACh presynaptic activity, accompanied by upregulation of nicotinic ACh receptors and 5HT receptors. Combined treatment elicited a greater deficit in ACh presynaptic activity than that seen with either agent alone, and upregulation of nAChRs and 5HT receptors was impaired or absent. The individual effects of nicotine and BaP accounted for only 60% of the combination effects, which thus displayed unique properties. Importantly, the combined nicotine + BaP exposure recapitulated the effects of tobacco smoke, distinct from nicotine. Our results show that the effects of nicotine on development of ACh and 5HT systems are worsened by BaP coexposure, and that combination of the two agents contributes to the greater impact of tobacco smoke on the developing brain. These results have important implications for the relative safety in pregnancy of nicotine-containing products compared with combusted tobacco, both for active maternal smoking and secondhand exposure, and for the effects of such agents in “dirty” environments with high PAH coexposure.

scholarly journals The Composition of Cigarette Smoke. An Historical Perspective of Several Polycyclic Aromatic Hydrocarbons

2009 ◽  
Vol 23 (6) ◽  
pp. 384-410 ◽  
Author(s):  
A Rodgman ◽  
LC Cook
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Melting Point ◽  
Cigarette Smoke ◽  
Aromatic Hydrocarbons ◽  
Tobacco Smoke ◽  
Individual Component ◽  
Complex Mixtures ◽  
Polycyclic Aromatic ◽  
The Individual ◽  
Cigarette Mainstream Smoke

AbstractBecause of the significant advancements in fractionation, analytical, and characterization technologies since the early 1960s, hundreds of components of complex mixtures have been accurately characterized without the necessity of actually isolating the individual component. This has been particularly true in the case of the complex mixtures tobacco and tobacco smoke. Herein, an historical account of a mid-1950 situation concerning polycyclic aromatic hydrocarbons (PAHs) in cigarette smoke is presented. While the number of PAHs identified in tobacco smoke has escalated from the initial PAH, azulene, identified in 1947 to almost 100 PAHs identified by late 1963 to more than 500 PAHs identified by the late 1970s, the number of PAHs isolated individually and characterized by several of the so-called classical chemical means (melting point, mixture melting point, derivative preparation and properties) in the mid-1950s and since is relatively few, 14 in all. They were among 44 PAHs identified in cigarette mainstream smoke and included the following PAHs ranging from bicyclic to pentacyclic: Acenaphthylene, 1,2-dihydroacenaphthylene, anthracene, benz[a]anthracene, benzo[a]pyrene, chrysene, dibenz[a, h]anthracene, fluoranthene, 9H-fluorene, naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, phenanthrene, and pyrene. One of them, benzo[a]pyrene, was similarly characterized in another study in 1959 by Hoffmann.

ALTERNATIVE ROUTES TO INNOVATION — THE EFFECTS OF CULTURAL AND STRUCTURAL FIT

2019 ◽  
Vol 24 (01) ◽  
pp. 2050006
Author(s):  
DAG INGVAR JACOBSEN ◽  
TORE HILLESTAD ◽  
BIRGITTE YTTRI ◽  
JARLE HILDRUM
Keyword(s):  
Response Rate ◽  
Organic Structure ◽  
Configurational Approach ◽  
Culture Strength ◽  
Individual Effects ◽  
Collective Phenomenon ◽  
The Individual ◽  
Alternative Routes ◽  
Innovative Culture ◽  
The Empirical Analysis

A configurational approach to organizations assumes that structural and cultural characteristics must be in “fit” to produce the wanted outcome. With a focus on innovation, this study examines empirically to what extent innovative activities with a large, global telecom company are produced by an innovative culture, an innovative structure, as well as the fit between the two. Based on an extensive survey (N = 21064, response rate = 65) of employees in seven countries in Europe and Asia, data was aggregated to unit level as culture by nature is a collective phenomenon. The empirical analysis detected both the individual effects of culture strength and homogeneity, structure, as well as the fit between the two. The results indicate that an innovative culture and an organic structure indeed fosters innovation, but that, somewhat surprisingly, there are not effects of the fit between the two. Both practical and theoretical implications are discussed.

Factors influencing the individual effects of blood transfusions on oxygen delivery and oxygen consumption*

2001 ◽  
Vol 29 (Supplement) ◽  
pp. S173-S179 ◽  
Author(s):  
Mattias Casutt ◽  
Burkhardt Seifert ◽  
Thomas Pasch ◽  
Edith R. Schmid ◽  
Marko I. Turina ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Delivery ◽  
Blood Transfusions ◽  
Factors Influencing ◽  
Individual Effects ◽  
The Individual

scholarly journals Influence of process variables on release properties of paracetamol tablets

2007 ◽  
Vol 57 (1) ◽  
pp. 73-86 ◽  
Author(s):  
Gbenga Alebiowu ◽  
Oludele Itiola
Keyword(s):  
Interaction Effects ◽  
Process Variables ◽  
Factorial Experimental Design ◽  
Disintegration Time ◽  
Individual Effects ◽  
Pregelatinized Starch ◽  
Tablet Formulations ◽  
Binder Concentration ◽  
The Individual ◽  
Paracetamol Tablet

Influence of process variables on release properties of paracetamol tablets A 23 factorial experimental design has been used to quantitatively study individual and interaction effects of the nature of binder (N), binder concentration (c) and relative density of tablet (d) on the disintegration time (DT) and dissolution times, t1, t50 and t90, of paracetamol tablet formulations. The factorial design was also used to study the quantitative effects of pregelatinization of starch binders on these parameters, i.e., N, c and d. In general, the most common ranking of the individual effects on DT, t1, t50 and t90 for native/native, pregelatinized/pregelatinized and native/pregelatinized starch binder formulations was c > d > N. For interaction effects, the most common ranking was N-c > c-d > N-d for all formulations. The results generally showed that c can considerably affect DT, t1, t50 and t90 of the tablets.

scholarly journals The tolerogenic interplay(s) among HLA-G, myeloid APCs, and regulatory cells

Blood ◽  
2011 ◽  
Vol 118 (25) ◽  
pp. 6499-6505 ◽  
Author(s):  
Edgardo D. Carosella ◽  
Silvia Gregori ◽  
Joel LeMaoult
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Immune Responses ◽  
Recent Work ◽  
Large Body ◽  
Regulatory Cells ◽  
Individual Effects ◽  
The Individual ◽  
Key Aspects ◽  
Antigen Presenting

Abstract Myeloid antigen-presenting cells (APCs), regulatory cells, and the HLA-G molecule are involved in modulating immune responses and promoting tolerance. APCs are known to induce regulatory cells and to express HLA-G as well as 2 of its receptors; regulatory T cells can express and act through HLA-G; and HLA-G has been directly involved in the generation of regulatory cells. Thus, interplay(s) among HLA-G, APCs, and regulatory cells can be easily envisaged. However, despite a large body of evidence on the tolerogenic properties of HLA-G, APCs, and regulatory cells, little is known on how these tolerogenic players cooperate. In this review, we first focus on key aspects of the individual relationships between HLA-G, myeloid APCs, and regulatory cells. In its second part, we highlight recent work that gathers individual effects and demonstrates how intertwined the HLA-G/myeloid APCs/regulatory cell relationship is.

MORPHOLOGICAL CHANGES IN THE ENDOCRINE PANCREAS IN PREGNANT RATS WITH EXPERIMENTAL DIABETES

1979 ◽  
Vol 80 (2) ◽  
pp. 175-179 ◽  
Author(s):  
F. A. VAN ASSCHE ◽  
L. AERTS ◽  
W. GEPTS
Keyword(s):  
Endocrine Pancreas ◽  
Experimental Diabetes ◽  
Morphological Changes ◽  
Normal Pregnancy ◽  
Β Cells ◽  
Pregnant Rats ◽  
Pregnant Rat ◽  
Human Pregnancy ◽  
The Individual

This present study has demonstrated that during normal pregnancy in the rat the number of β-cells is increased (hyperplasia) and the volume of the individual β-cells is increased (hypertrophy). During experimental diabetes, however, the endocrine pancreas has an impaired capacity to compensate during pregnancy. In the experimental diabetic pregnant rat the β-cells cannot replicate due to the unfavourable metabolic environment. This could reflect the complications caused by diabetes during human pregnancy.

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