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Respiratory System (respiratory + system)
Selected AbstractsEvolution of the Respiratory System in Nonavian Theropods: Evidence From Rib and Vertebral MorphologyTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 9 2009Emma R. Schachner Abstract Recent reports of region-specific vertebral pneumaticity in nonavian theropod dinosaurs have brought attention to the hypothesis that these animals possessed an avian-style respiratory system with flow-through ventilation. This study explores the thoracic rib and vertebral anatomy of Sinraptor, Allosaurus, Tyrannosaurus, and Deinonychus; four nonavian theropods that all show well-preserved thoracic vertebrae and ribs. Comparisons to the osteology and soft tissue anatomy of extant saurians provide new evidence supporting the hypothesis of flow-through ventilation in nonavian theropods. Analyses of diapophyseal and parapophyseal position and thoracic rib morphology suggest that most nonavian theropods possessed lungs that were deeply incised by the adjacent bicapitate thoracic ribs. This functionally constrains the lungs as rigid nonexpansive organs that were likely ventilated by accessory nonvascularized air sacs. The axial anatomy of this group also reveals that a crocodilian-like hepatic-piston lung would be functionally and biomechanically untenable. Taken together with the evidence that avian-like air sacs were present in basal theropods, these data lead us to conclude that an avian-style pulmonary system was likely a universal theropod trait. Anat Rec, 292:1501,1513, 2009. 2009. © 2009 Wiley-Liss, Inc. [source] Macroscopic Anatomy of the Ringed Seal [Pusa (Phoca) hispida] Lower Respiratory SystemANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2009H. Smodlaka Summary This investigation serves to document the normal anatomical features of the lower respiratory tract of the ringed seal [Pusa (phoca) hispida]. Evaluation of embalmed specimens and tracheobronchial casts showed that the right lung of this seal consists of four lobes while the left has only three lobes. The ventral margins of the lungs do not reach the sternum causing them to form the boundary of the broad recessus costomediastinalis. Lung lobation corresponds with bronchial tree division. Pulmonary venous drainage includes right and left common veins draining ipsilateral cranial and middle lung lobes, and one common caudal vein draining both caudal lobes and the accessory lobe. The right and left pulmonary arteries divide into cranial and caudal branches at the level of the principal bronchus. The ringed seal has three tracheobronchial lymph nodes. The trachea has an average of 87 cartilages that exhibit a pattern of random anastomoses between adjacent rings. The trachea exhibits to a small degree the dorsoventrally flattened pattern that is described in other pinnipeds. The tracheal diameter is smaller than that of the canine. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 8 2010Article first published online: 27 SEP 2010 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 12 sections: 1 Reviews; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro-organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 2 2010Article first published online: 22 FEB 2010 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 12 sections: 1 Reviews; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro-organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 10 2009Article first published online: 9 DEC 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 12 sections: 1 Reviews; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro-organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 6 2009Article first published online: 3 JUL 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 12 sections: 1 Reviews; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro-organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 8 2008Article first published online: 5 SEP 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 11 sections: 1 Reviews; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro-organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 4 2008Article first published online: 25 APR 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 11 sections: 1 Reviews; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro-organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current awareness in NMR in biomedicineNMR IN BIOMEDICINE, Issue 3 2008Article first published online: 18 MAR 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 11 sections: 1 Reviews; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro-organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 7 2006Article first published online: 31 OCT 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 11 sections: 1 Books, Reviews ' Symposia; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro-organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 5 2006Article first published online: 26 JUL 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 11 sections: 1 Books, Reviews ' Symposia; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro-organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 2 2006Article first published online: 16 MAR 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 11 sections: 1 Books, Reviews ' Symposia; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro-organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 8 2004Article first published online: 23 DEC 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 11 sections: 1 Books, Reviews ' Symposia; 2 General; 3 Technology; 4 Brain and Nerves; 5 Neuropathology; 6 Cancer; 7 Cardiac, Vascular and Respiratory Systems; 8 Liver, Kidney and Other Organs; 9 Muscle and Orthopaedic; 10 Plants, Micro-organisms and Parasites; 11 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in NMR in BiomedicineNMR IN BIOMEDICINE, Issue 6-7 2003Article first published online: 3 DEC 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 9 sections: 1 Books, Reviews ' Symposia; 2 General; 3 Technology; 4 Brain and Nerves; 5 Neuropathology; 6 Cancer; 7 Cardiac, Vascular and Respiratory Systems; 8 Liver, Kidney and Other Organs; 9 Muscle and Orthopaedic. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Endoderm development in vertebrates: fate mapping, induction and regional specificationDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 6 2005Kimiko Fukuda The formation of the vertebrate body plan begins with the differentiation of cells into three germ layers: ectoderm, mesoderm and endoderm. Cells in the endoderm give rise to the epithelial lining of the digestive tract, associated glands and respiratory system. One of the fundamental problems in developmental biology is to elucidate how these three primary germ layers are established from the homologous population of cells in the early blastomere. To address this question, ectoderm and mesoderm development have been extensively analyzed, but study of endoderm development has only begun relatively recently. In this review, we focus on the ,where', ,when' and ,how' of endoderm development in four vertebrate model organisms: the zebrafish, Xenopus, chick and mouse. We discuss the classical fate mapping of the endoderm and the more recent progress in characterizing its induction, segregation and regional specification. [source] Expression of histamine receptors and effect of histamine in the rat carotid body chemoafferent pathwayEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2006Nikolai Lazarov Abstract Chemosensory information from peripheral arterial oxygen sensors in the carotid body is relayed by petrosal ganglion neurons to the respiratory networks in the medulla oblongata. Biogenic amines, including histamine, released from glomus (type I) cells of the carotid body are considered to be primary transmitters in hypoxic chemosensitivity. Immunocytochemistry at light-and electron-microscopical levels, and RT-PCR, revealed the expression of histamine receptors 1 and 3 as well as histidine decarboxylase in the rat carotid body glomus cells and petrosal ganglion neurons. Histamine receptors 1 and 3, but not histidine decarboxylase, were also observed in the ventrolateral, intermediate and commissural subnuclei of the nucleus tractus solitarii in the medulla oblongata. In order to examine the possible role of histamine in the afferent branch of the respiratory system, we applied histamine receptor 1 and 3 agonists to the carotid body, which caused a mildly increased phrenic nerve activity in a working heart,brainstem preparation. Moreover, microinjection of antagonists of histamine receptors 1 and 3 into the nucleus tractus solitarii caused significant changes in the inspiratory timing and the chemoreceptor response. Our data show that histamine acting via histamine receptors 1 and 3 plays an important neuromodulatory role in the afferent control of chemosensitivity. [source] Ret deficiency in mice impairs the development of A5 and A6 neurons and the functional maturation of the respiratory rhythmEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2005J. C. Viemari Abstract Although a normal respiratory rhythm is vital at birth, little is known about the genetic factors controlling the prenatal maturation of the respiratory network in mammals. In Phox2a mutant mice, which do not express A6 neurons, we previously hypothesized that the release of endogenous norepinephrine by A6 neurons is required for a normal respiratory rhythm to occur at birth. Here we investigated the role of the Ret gene, which encodes a transmembrane tyrosine kinase receptor, in the maturation of norepinephrine and respiratory systems. As Ret -null mutants (Ret,/,) did not survive after birth, our experiments were performed in wild-type (wt) and Ret,/, fetuses exteriorized from pregnant heterozygous mice at gestational day 18. First, in wt fetuses, quantitative in situ hybridization revealed high levels of Ret transcripts in the pontine A5 and A6 areas. Second, in Ret,/, fetuses, high-pressure liquid chromatography showed significantly reduced norepinephrine contents in the pons but not the medulla. Third, tyrosine hydroxylase immunocytochemistry revealed a significantly reduced number of pontine A5 and A6 neurons but not medullary norepinephrine neurons in Ret,/, fetuses. Finally, electrophysiological and pharmacological experiments performed on brainstem ,en bloc' preparations demonstrated impaired resting respiratory activity and abnormal responses to central hypoxia and norepinephrine application in Ret,/, fetuses. To conclude, our results show that Ret gene contributes to the prenatal maturation of A6 and A5 neurons and respiratory system. They support the hypothesis that the normal maturation of the respiratory network requires afferent activity corresponding to the A6 excitatory and A5 inhibitory input balance. [source] Look on the positive side!FEMS MICROBIOLOGY LETTERS, Issue 2 2007Archaeal' membrane-bound nitrate reductases, The orientation, bioenergetics of, identification Abstract Many species of Bacteria and Archaea respire nitrate using a molybdenum-dependent membrane-bound respiratory system called Nar. Classically, the ,Bacterial' Nar system is oriented such that nitrate reduction takes place on the inside of this membrane. However, the active site subunit of the ,Archaeal' Nar systems has a twin arginine (,RR') motif, which is a suggestion of translocation to the outside of the cytoplasmic membrane. These ,Archaeal' type of nitrate reductases are part of a group of molybdoenzymes with an ,RR' motif that are predicted to have an aspartate ligand to the molybdenum ion. This group includes selenate reductases and possible sequence signatures are described that serve to distinguish the Nar nitrate reductases from the selenate reductases. The ,RR' sequences of nitrate reductases of Archaea and some that have recently emerged in Bacteria are also considered and it is concluded that there is good evidence for there being both Archaeal and Bacterial examples of Nar-type nitrate reductases with an active site on the outside of the cytoplasmic membrane. Finally, the bioenergetic consequences of nitrate reduction on the outside of the cytoplasmic membrane have been explored. [source] Respiratory protection of nitrogenase in Azotobacter species: is a widely held hypothesis unequivocally supported by experimental evidence?FEMS MICROBIOLOGY REVIEWS, Issue 4 2000Jürgen Oelze Abstract The hypothesis of respiratory protection, originally formulated on the basis of results obtained with Azotobacter species, postulates that consumption of O2 at the surface of diazotrophic prokaryotes protects nitrogenase from inactivation by O2. Accordingly, it is assumed that, at increased ambient O2 concentrations, nitrogenase activity depends on increased activities of a largely uncoupled respiratory electron transport system. The present review compiles evidence indicating that cellular O2 consumption as well as both the activity and the formation of the respiratory system of Azotobacter vinelandii are controlled by the C/N ratio, that is to say the ratio at which the organism consumes the substrate (i.e. the source of carbon, reducing equivalents and ATP) per source of compound nitrogen. The maximal respiratory capacity which can be attained at increased C/N ratios, however, is controlled, within limits, by the ambient O2 concentration. When growth becomes N-limited at increased C/N ratios, cells synthesize nitrogenase and fix N2. Under these diazotrophic conditions, cellular O2 consumption remains constant at a level controlled by the O2 concentration. Control by O2 has been studied on the basis of both whole cell respiration and defined segments of the respiratory electron transport chain. The results demonstrate that the effect of O2 on the respiratory system is restricted to the lower range of O2 concentrations up to about 70 ,M. Nevertheless, azotobacters are able to grow diazotrophically at dissolved O2 concentrations of up to about 230 ,M indicating that respiratory protection is not warranted at increased ambient O2 concentrations. This conclusion is supported and extended by a number of results largely excluding an obvious relationship between nitrogenase activity and the actual rate of cellular O2 consumption. On the basis of theoretical calculations, it is assumed that the rate of O2 diffusion into the cells is not significantly affected by respiration. All of these results lead to the conclusion that, in the protection of nitrogenase from O2 damage, O2 consumption at the cell surface is less effective than generally assumed. It is proposed that alternative factors like the supply of ATP and reducing equivalents are more important. [source] Dangers relating to fires in carbon-fibre based composite materialFIRE AND MATERIALS, Issue 4 2005Tommy Hertzberg Abstract Inhalable carbon fibres have been suspected to pose similar threats to human health as asbestos fibres. It is well-known that fibres having a diameter of less than 3 µm might be inhaled and transported deep into the human respiratory system. Some composite materials use carbon fibres as structural reinforcement. These fibres do not pose any risks as such as they are firmly connected to the laminate and surrounded by a polymer matrix. Also, these fibres typically have diameters >6 µm and thus, are not inhalable. However, if the material is exposed to a fire, the carbon material might be oxidized and fractionated and thereby, inhalable fibres might be generated into the fire smoke. The capability of carbon fibre-based composite material to produce dangerous inhalable fibres from different combustion scenarios has been investigated. It was found that the risk of fires generating inhalable carbon fibres is related to the surface temperature, the oxygen level and the airflow field close to the material surface. The temperatures necessary for oxidation of the carbon fibre is so high that it is possible that only a flashover situation will pose any real danger. Other possible danger scenarios are highly intense fires (e.g. a liquid fuel fire), or situations where structural damage is part of the fire scenario. Copyright © 2005 John Wiley & Sons, Ltd. [source] Phosphoinositide 3-kinase signalling in lung disease: leucocytes and beyondIMMUNOLOGY, Issue 4 2007David A. Medina-Tato Summary The family of lipid kinases termed phosphoinositide-3-kinase (PI3K) is known to contribute at multiple levels to innate and adaptive immune responses, and is hence an attractive target for drug discovery in inflammatory and autoimmune disease, including respiratory diseases. The development of isoform-selective pharmacological inhibitors, targeted gene manipulation and short interfering RNA (siRNA) target validation have facilitated a better understanding of the role that each member of this family of kinases plays in the physiology and pathology of the respiratory system. In this review, we will evaluate the evidence for the roles of specific PI3K isoforms in the lung and airways, and discuss their potential as targets for novel drug therapies. [source] Improving M cell mediated transport across mucosal barriers: do certain bacteria hold the keys?IMMUNOLOGY, Issue 1 2004Angela L. Man Summary Specialized microfold (M) cells of the follicle-associated epithelium (FAE) of the mucosal-associated lymphoid tissue (MALT) in gut and the respiratory system play an important role in the genesis of both mucosal and systemic immune responses by delivering antigenic substrate to the underlying lymphoid tissue where immune responses start. Although it has been shown that dendritic cells (DC) also have the ability to sample antigens directly from the gut lumen, M cells certainly remain the most important antigen-sampling cell to be investigated in order to devise novel methods to improve mucosal delivery of biologically active compounds. Recently, novel information on the interactions between bacteria and FAE have come to light that unveil further the complex cross-talk taking place at mucosal interfaces between bacteria, epithelial cells and the immune system and which are central to the formation and function of M cells. In particular, it has been shown that M cell mediated transport of antigen across the FAE is improved rapidly by exposure to certain bacteria, thus opening the way to identify new means to achieve a more effective mucosal delivery. Here, these novel findings and their potential in mucosal immunity are analysed and discussed, and new approaches to improve antigen delivery to the mucosal immune system are also proposed. [source] Towards a comprehensive computational model for the respiratory system,INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 7 2010Wolfgang A. Wall Abstract This paper is concerned with computational modeling of the respiratory system against the background of acute lung diseases and mechanical ventilation. Conceptually, we divide the lung into two major subsystems, namely the conducting airways and the respiratory zone represented by lung parenchyma. Owing to their respective complexity, both parts are themselves out of range for a direct numerical simulation resolving all relevant length scales. Therefore, we develop detailed individual models for parts of the subsystems as a basis for novel multi-scale approaches taking into account the unresolved parts appropriately. In the tracheobronchial region, CT-based geometries up to a maximum of approximately seven generations are employed in fluid,structure interaction simulations, considering not only airway wall deformability but also the influence of surrounding lung tissue. Physiological outflow boundary conditions are derived by considering the impedance of the unresolved parts of the lung in a fully coupled 3D-1D approach. In the respiratory zone, an ensemble of alveoli representing a single ventilatory unit is modeled considering not only soft tissue behavior but also the influence of the covering surfactant film. Novel nested multi-scale procedures are then employed to simulate the dynamic behavior of lung parenchyma as a whole and local alveolar ensembles simultaneously without resolving the alveolar micro-structure completely. Copyright © 2010 John Wiley & Sons, Ltd. [source] Symposium on the respiratory systemJOURNAL OF ANATOMY, Issue 4 2002John Bannigan No abstract is available for this article. [source] Spontaneous neoplasia in the baboon (Papio spp.)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 2 2007Rachel E. Cianciolo Abstract Background, There are several comprehensive reviews of spontaneous neoplasia in non-human primates that compile individual cases or small numbers of cases, but do not provide statistical analysis of tumor incidence, demographics, or epidemiology. Methods, This paper reports all spontaneous neoplasms (n = 363) diagnosed over a 15-year period in a baboon colony with an average annual colony population of 4000. Results, A total of 363 spontaneous neoplasms were diagnosed in 313 baboons: 77 cases were males (25%) and 236 were females (75%); ages ranged from 1 month to 33 years (mean 16.5, median 17). Conclusions, The organ systems affected in descending order of number of neoplasms were hematopoietic organs (n = 101, 28%), urogenital tract (n = 78, 21%), integument (n = 43, 12%), alimentary tract (n = 43, 12%), endocrine organs (n = 40, 11%), nervous system (n = 33, 9%), musculoskeletal system (n = 5, 1%), and respiratory system (n = 4, 1%). Malignant cases numbered 171 (47%); 192 (53%) cases were benign. [source] Beneficial effects of high positive end-expiratory pressure in lung respiratory mechanics during laparoscopic surgeryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2009L. F. MARACAJĮ-NETO Background: The effect of neuromuscular blockade (NMB) and positive end-expiratory pressure (PEEP) on the elastic properties of the respiratory system during pneumoperitoneum (PnP) remains a controversial subject. The main objective of the present study was to evaluate the effects of NMB and PEEP on respiratory mechanics. Methods: We performed a dynamic analysis of respiratory mechanics in patients subjected to PnP. Twenty-one patients underwent cholecystectomy videolaparoscopy and total intravenous anesthesia. The respiratory system resistance (RRS), pulmonary elastance (EP), chest wall elastance (ECW), and respiratory system elastance (ERS) were computed via the least squares fit technique using an equation describing the motion of the respiratory system, which uses primary signs such as airway pressure, tidal volume, air flow, and esophageal pressures. Measurements were taken after tracheal intubation, PnP, NMB, establishment of PEEP (10 cmH2O), and PEEP withdrawal [zero end-expiratory pressure (ZEEP)]. Results: PnP significantly increased ERS by 27%; both EP and ECW increased 21.3 and 64.1%, respectively (P<0.001). NMB did not alter the respiratory mechanic properties. Setting PEEP reduced ERS by 8.6% (P<0.05), with a reduction of 10.9% in EP (P<0.01) and a significant decline of 15.7% in RRS (P<0.05). These transitory changes in elastance disappeared after ZEEP. Conclusions: We concluded that the 10 cmH2O of PEEP attenuates the effects of PnP in respiratory mechanics, lowering RRS, EP, and ERS. These effects may be useful in the ventilatory approach for patients experiencing a non-physiological increase in IAP owing to PnP in laparoscopic procedures. [source] Promoting complex systems learning through the use of conceptual representations in hypermediaJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 9 2009Lei Liu Abstract Studying complex systems is increasingly important in many science domains. Many features of complex systems make it difficult for students to develop deep understanding. Our previous research indicated that a function-centered conceptual representation is part of the disciplinary toolbox of biologists, suggesting that it is an appropriate representation to help students develop deep understanding. This article reports on the results of two experiments that investigate how hypermedia using a conceptual representation influences pre-service teachers' and middle school students' learning of a complex biological system, the human respiratory system. We designed two versions of instructional hypermedia based on the structure,behavior-function conceptual representation. One hypermedia was function-centered which emphasized the function and behavior of the system, whereas the other was focused on the structure of the system. We contrasted the instructional effectiveness of these two alternative conceptual representations. The results of both studies indicated that participants using the function-centered hypermedia developed deeper understanding than those using the structure-centered version. This proof-of-concept study suggests that the function-centered conceptual representation is a powerful way to promote complex systems understanding. © 2009 Wiley Periodicals, Inc. J Res Sci Teach 46: 1023,1040, 2009 [source] Resistive load of laryngeal mask airway and proseal laryngeal mask airway in mechanically ventilated patientsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2003G. Natalini Background:, The ProSeal Laryngeal Mask Airway (PLMA) ventilation tube is narrower and shorter than the standard Laryngeal Mask Airway (LMA) and is without the vertical bars at the end of the tube. In this randomized, crossover study, PLMA and LMA resistances were compared. Methods:, Respiratory mechanics was calculated in 26 anesthetized, mechanically ventilated patients with both LMA and PLMA. The laryngeal mask positioning was fiberoptically evaluated. Differences in the respiratory mechanics of the LMA and the PLMA were attributed to the differences between the laryngeal masks. Results:, In the total study population the airway resistance was 1.5 ± 2.6 hPa.l,1.s,1 (P = 0.005) higher with the PLMA than with the LMA. During the PLMA use, the peak expiratory flow reduced by 0.02 ± 0.05 l min,1 (P = 0.046), the expiratory resistance increased by 0.6 ± 1.3 hPa.l,1.s,1 (P = 0.022), and the time constant of respiratory system lengthened by 0.09 ± 0.18 s (P = 0.023). These differences doubled when the LMA was better positioned than the PLMA, whereas they disappeared when the PLMA was positioned better than the LMA. Conclusions:, The standard LMA offers a lower resistive load than the PLMA. Moreover, the fitting between the laryngeal masks and the larynx, as fiberoptically evaluated, plays a major role in determining the resistive properties of these devices. [source] Social class inequalities in childhood mortality and morbidity in an English populationPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 1 2006Stavros Petrou Summary The objective of this study was to examine the association between social class of the head of household at the time of birth and mortality and morbidity during the first 10 years of life in a cohort of all 117 212 children born to women who both lived, and delivered in hospital, in Oxfordshire or West Berkshire during the period 1 January 1979 to 31 December 1988. Logistic regression was used to estimate social class gradients, with odds ratios (OR), for mortality during the early neonatal period, late neonatal period, post-neonatal period, post-infancy period and throughout the first 10 years of life. Logistic regression was also used to estimate social class gradients, with ORs, for hospital admission rates for 16 broad groups of diseases during years 0,3, 4,6, 7,10 and throughout the first 10 years of life. Poisson regression was used to estimate social class gradients, with effect sizes, for overall hospital admission rates during years 0,3, 4,6, 7,10 and throughout the first 10 years of life. The study revealed a significant social class gradient in mortality during the first 10 years of life (adjusted OR for each decrement in social class category 1.08; [95% confidence interval 1.03, 1.14]). The study also revealed a significant adjusted social class gradient in hospital admission rates for 14 of the 16 groups of diseases during the first 10 years of life. For the majority of these, the social class gradients had attenuated somewhat by the later childhood years. However, the social class gradient persisted throughout the first 10 years of life for diseases of the respiratory system (1.07 [1.05, 1.08]), diseases of the digestive system (1.06 [1.04, 1.09]), and injury and poisoning (1.07 [1.06, 1.09]). In addition, a significant adjusted social class gradient was found in overall hospital admission rates for each age group studied. This study suggests that there are significant social class inequalities in a wide range of adverse child health outcomes. [source] Matrix metalloproteinases, a disintegrin and metalloproteinases, and a disintegrin and metalloproteinases with thrombospondin motifs in non-neoplastic diseasesPATHOLOGY INTERNATIONAL, Issue 7 2010Takayuki Shiomi Cellular functions within tissues are strictly regulated by the tissue microenvironment which comprises extracellular matrix and extracellular matrix-deposited factors such as growth factors, cytokines and chemokines. These molecules are metabolized by matrix metalloproteinases (MMP), a disintegrin and metalloproteinases (ADAM) and ADAM with thrombospondin motifs (ADAMTS), which are members of the metzincin superfamily. They function in various pathological conditions of both neoplastic and non-neoplastic diseases by digesting different substrates under the control of tissue inhibitors of metalloproteinases (TIMP) and reversion-inducing, cysteine-rich protein with Kazal motifs (RECK). In neoplastic diseases MMP play a central role in cancer cell invasion and metastases, and ADAM are also important to cancer cell proliferation and progression through the metabolism of growth factors and their receptors. Numerous papers have described the involvement of these metalloproteinases in non-neoplastic diseases in nearly every organ. In contrast to the numerous review articles on their roles in cancer cell proliferation and progression, there are very few articles discussing non-neoplastic diseases. This review therefore will focus on the properties of MMP, ADAM and ADAMTS and their implications for non-neoplastic diseases of the cardiovascular system, respiratory system, central nervous system, digestive system, renal system, wound healing and infection, and joints and muscular system. [source] | |||||||||||||||||||