| 1. |
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| 2. |
- Boden, K., et al.
(författare)
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Swallowing and respiratory pattern in young healthy individuals recorded with high temporal resolution
- 2009
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Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925 .- 1365-2982. ; 21:11, s. 1163-1163
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Tidskriftsartikel (refereegranskat)abstract
- P>The coordination of swallowing and respiration is essential for a safe swallow. Swallowing consists of several subsecond events. To study this, it is important to use modalities with high temporal resolution. In this study, we have examined young healthy individuals with simultaneous videofluoroscopy, videomanometry and respiratory recording, all with high temporal resolution. The onset of 13 predetermined swallowing and respiratory events and the surrounding respiratory phase pattern were studied in different body positions and during different respiratory drives. An increased respiratory drive was induced by breathing 5% CO2. The results demonstrated a highly repeatable and fixed temporal coordination of the swallowing pattern despite body position and respiratory drive. Previous studies have demonstrated a period of centrally controlled apnoea during swallowing. This apnoea period has a variable length, varying from 1 to 5 s. During increased respiratory drive, we could demonstrate a significantly shorter period of apnoea during swallowing, mainly due to an earlier resumption of respiration. The high temporal recordings in this study have revealed that swallowing during expiration is present basically in all healthy individuals. This swallowing respiratory pattern seems to be appropriate for a safe swallow. This knowledge will be used as a reference for future studies on how swallowing and respiratory coordination might be altered due to ageing and diseases.
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| 3. |
- Cedborg, A. I. Hardemark, et al.
(författare)
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Breathing and swallowing in normal man - effects of changes in body position, bolus types, and respiratory drive
- 2010
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Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925 .- 1365-2982. ; 22:11, s. 1201-1201
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Tidskriftsartikel (refereegranskat)abstract
- Background Coordination of breathing and swallowing is essential for airway protection and dyscoordination may cause morbidity and mortality. Methods Using a recently developed technique for high accuracy respiratory measurements of airflow during swallowing, we investigated the effects of body position (upright vs left lateral), bolus type (spontaneously swallowed saliva vs water), and respiratory drive (normo- vs hypercapnia) on coordination of breathing and swallowing in 32 healthy volunteers. Key Results Swallows were in all cases (100%) proceded by expiration and 98% were also followed by expiration, regardless of body position, bolus type, or respiratory drive. While the endpoint of postswallow apnea correlated well to the endpoint of pharyngeal swallowing, duration of preswallow apnea was highly variable. In a small fraction of swallows followed by inspiration (3%), the expiratory phase before swallowing and duration of postswallow apnea was significantly longer. Body position and respiratory drive affected the increase in upper esophageal sphincter tone during inspiration. Increased respiratory drive also reduced swallowing frequency and shortened duration of preswallow apnea. Water swallows had longer duration of preswallow apnea. Conclusions & Inferences Swallowing occurs during the expiratory phase of respiration, and the fraction of swallows preceded and followed by expiration approach 100% in healthy humans. This integration between breathing and swallowing remains unchanged regardless of body position, bolus characteristics, or respiratory drive. Our results provide a platform for future studies aiming at understanding how this integration is changed by aging, diseases, and drugs.
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| 4. |
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| 5. |
- Corcoran, E. C., et al.
(författare)
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Thermodynamic investigations of the uranium-molybdenum-oxygen system by a coupling of density functional theory and CALPHAD methodologies
- 2018
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Ingår i: Calphad. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0364-5916 .- 1873-2984. ; 63, s. 196-211
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Tidskriftsartikel (refereegranskat)abstract
- This paper examines the development of a consistent thermodynamic model for the uranium (U) - molybdenum (Mo) - oxygen (0) system for incorporation into the Thermodynamics of Advanced Fuels - International Database (TAF-ID). Phase diagram data and thermodynamic properties from the literature are reviewed. Density functional theory ab initio calculations at 0 K are combined with a quasi -harmonic statistical thermodynamic model to calculate thermodynamic functions (e.g., integral Delta H-298.15K(0), S-298.15K(0), and C-p(0) (T))of the relevant ternary compounds when little or no thermodynamic literature data are available. A CALPHAD method is employed to derive a model describing the Gibbs energy functions for all the relevant ternary compounds, the liquid phase, and the gas phase of the U-Mo-O system. A consistent thermodynamic model is obtained for the Mo-U-0 system with a special emphasis placed on the oxygen rich portion of the ternary (ie., MoO2-UO2-O). Finally, supporting binary and pseudo binary diagrams (e.g., Mo-O, UO2-MoO3 and UO3-MoO3) are computed and compared to literature data.
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| 7. |
- Ekberg, Olle, et al.
(författare)
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An In Vitro Model for Studying Neuromuscular Transmission in the Mouse Pharynx.
- 2009
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Ingår i: Dysphagia. - : Springer Science and Business Media LLC. - 1432-0460 .- 0179-051X. ; 24, s. 32-39
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Tidskriftsartikel (refereegranskat)abstract
- The muscles of the pharynx are controlled by networks of neurons under the control of specific regions in the brain stem, which have been fairly well studied. However, the transmission between these neurons and the pharyngeal muscles, at the motor end plates, is less well understood. Therefore, an in vitro model for the study of neuromuscular transmission in the pharyngeal muscle of the mouse was developed. Ring preparations from the inferior constrictor and the cricopharyngeus muscles were isolated and mounted for isometric force recording at physiologic temperature. Preparations from the diaphragm and the soleus muscles were examined in parallel. The muscles were stimulated at supramaximal voltage with short tetani at 100 Hz. Following direct stimulation of the muscle fibers, using a longer pulse duration, the rate of force development of the pharyngeal muscles was similar to that of the diaphragm and faster than that of the soleus muscle. By varying the duration of the stimulation pulses, conditions where the nerve-mediated activation contributed to a major extent of the contractile responses were identified. Gallamine completely inhibited the nerve-mediated responses. In separate experiments the dose dependence of gallamine inhibition was examined, showing similar sensitivity in the inferior pharyngeal constrictor compared to the diaphragm and soleus muscles. We conclude that reproducible contractile responses with an identifiable nerve-induced component can be obtained from the mouse inferior pharyngeal constrictor. The pharyngeal muscles have contractile characteristics similar to those of the faster diaphragm. The sensitivity to the neuromuscular blocking agent gallamine of the inferior pharyngeal constrictor was in the same concentration range as that of the diaphragm and soleus muscles.
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| 8. |
- Ekman, A., et al.
(författare)
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Neuromuscular block and the electroencephalogram during sevoflurane anaesthesia
- 2007
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Ingår i: NeuroReport. - 0959-4965 .- 1473-558X. ; 18:17, s. 1817-1820
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Tidskriftsartikel (refereegranskat)abstract
- The effect of neuromuscular block on the anaesthetic depth of hypnosis is an elusive question. We simultaneously investigated the influence of neuromuscular block on the bispectral index, a measure of hypnosis during general anaesthesia, and on the electroencephalogram. Patients were anaesthetized with sevoflurane. Noxious tetanic electrical stimulation was applied on two occasions: before and after profound neuromuscular block achieved with rocuronium. Neuromuscular block significantly attenuated the effect from noxious stimulation on electroencephalogram power and synchrony in the γ band (P<0.05), and the corresponding effect on bispectral index (P<0.02). These findings are probably due to the reduced arousing afferent input from paralysed muscles, and not to changes in the frontal electromyogram.
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| 9. |
- Ekman, A., et al.
(författare)
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The effect of neuromuscular block and noxious stimulation on hypnosis monitoring during sevoflurane anesthesia
- 2007
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Ingår i: Anesthesia and Analgesia. - : Ovid Technologies (Wolters Kluwer Health). - 0003-2999 .- 1526-7598. ; 105:3, s. 688-695
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: There are conflicting results on the influence of neuromuscular block (NMB) on the bispectral index (BIS). We investigated the influence of two degrees of NMB on BIS, Alaris auditory-evoked potential index (AAI), and the electromyogram (EMG) obtained with needle electrodes from the frontal and temporal muscles, immediately adjacent to the BIS-sensor. METHODS: Twenty patients were anesthetized with sevoflurane, titrated for 30 min to an end-tidal concentration of 1.2% (baseline). Rocuronium was infused to 50% (partial) and 95% (profound) depression of the first twitch in a train-of-four response, the order being randomly chosen. Noxious tetanic electrical stimulation was applied at four occasions: 1) at baseline (control measurement), 2 and 3) at each degree of NMB, and 4) after neostigmine reversal. BIS, AAI, and EMG were obtained 2 min before and 2 min after each noxious stimulation. RESULTS: Median BIS and AAI at baseline were 44 (39-50) and 15 (14-16), respectively. The two degrees of NMB did not affect BIS, AAI, and EMG before noxious stimulation. In contrast, profound NMB altered the BIS and AAI responses to noxious stimulation when compared with partial NMB, (BIS P = 0.01, AAI P < 0.01), after neostigmine reversal (BIS P < 0.01, AAI P = 0.01) and compared with baseline (BIS P = 0.08, AAI P = 0.02). No significant increase in EMG was found. CONCLUSION: BIS and AAI responses to noxious tetanic electrical stimulation are affected by the degree of NMB during sevoflurane anesthesia whereas NMB does not affect BIS or AAI in the absence of noxious stimulation.
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| 10. |
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| 11. |
- Jensen, Per, et al.
(författare)
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The Genetics of How Dogs Became Our Social Allies
- 2016
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Ingår i: Current directions in psychological science (Print). - : Sage Publications. - 0963-7214 .- 1467-8721. ; 25:5, s. 334-338
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Tidskriftsartikel (refereegranskat)abstract
- Dogs were domesticated from wolves about 15,000 years ago, and an important selection pressure (intentional orunintentional) has been their ability to communicate and cooperate with people. They show extensive human-directedsociability, which varies within as well as between breeds and is not shared by ancestral wolves. Hence, dogs arepotentially ideal models for studying the genetics of social behavior. Here, we review some recent research carried outby us and others on this subject. We present results showing that recent selection of different breed types can be usedas a model system for investigating the genetic architecture of personalities. Furthermore, we review data showingthat human-directed social behavior is significantly related to a small number of genes that have known connectionsto human social disorders such as autism and schizophrenia. We suggest that dogs are excellent study subjects foranalyzing the evolution and genetics of social behavior and can serve as probes for human health and welfare.
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| 12. |
- Jilal, I, et al.
(författare)
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New benzyloxyethyl cellulose (BEC) crosslinked EDTA : synthesis, characterization and application for supramolecular self-assembling nanoencapsulation of Pb (II)
- 2019
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Ingår i: Materials today: Proceedings. - : Elsevier. - 2214-7853. ; , s. 909-919
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Konferensbidrag (refereegranskat)abstract
- Cellulosic derivatives-modification by Ethylenediaminetetraacetic acid dianhydride (EDTAD) leads to an advanced state of the crosslinking degree, which often limits the adsorbent-metal ion interactions at the superficial level. Moreover, the specific area decreases by increasing crosslinking degree, resulting in a degradation of the adsorptive properties of the materials. In the present work, a new synthesis strategy of crosslinkedcellulose derivative with Ethylenediaminetetraacetic acid (EDTA) was proposed. The preparation of the adsorbent was based on the hydrophobation of hydroxyethyl cellulose (HEC) by partial benzylation (DS similar to 1). This helped to obtain a new cellulose derivative (Benzyloxyethyl cellulose (BEC)) soluble in the majority of the usual solvents, and the EDTA grafting reaction was performed under homogeneous conditions to ensure homogenous distribution of the chelating sites. The resulting BEC-EDTA material was then characterized by FT-IR, SEM and TGA. Thus, the Pb (II)-adsorption behavior on the bio-adsorbent was studied at the supramolecular level and the study of changes in adsorbent morphology before and after modification was performed based on SEM images and EDX spectra. Effect of Pb (II) on BEC-EDTA morphology was investigated as well. However, a self-assembly of BEC-EDTA as nanometric rods in the presence of Pb (II) ions was a strong indication of the Pb (II) nano-encapsulation in a stable polymer network. (c) 2019 Elsevier Ltd. All rights reserved.
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| 17. |
- Prins, S. N., et al.
(författare)
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Thermodynamic assessment of the Al-Ru system
- 2003
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Ingår i: Calphad. - : Elsevier BV. - 0364-5916 .- 1873-2984. ; 27:1, s. 79-90
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Tidskriftsartikel (refereegranskat)abstract
- The CALPHAD technique was used to calculate the Al-Ru binary phase diagram. The RuAl (B2) phase was described with the sublattice model (SL), also designated Compound Energy Formalism (CEF), as well as the Modified Sublattice Formalism (MSL), which describes the order disorder transformation with one Gibbs energy function. The RuAl6 phase was described as a stoichiometric phase and the remaining intermetallic phases (Ru4Al13, RuAl2 and Ru2Al3) were modelled with the sublattice model. The solubility of Ru in (Al) was considered negligible. Good agreement was obtained between the calculated and the experimental phase diagrams.
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| 20. |
- Sundman, E A, et al.
(författare)
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Chronic Maxillary Sinusitis in Medieval Sigtuna, Sweden : A Study of Sinus Health and Effects on Bone Preservation
- 2013
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Ingår i: International journal of osteoarchaeology. - : Wiley. - 1047-482X .- 1099-1212. ; 23:4, s. 447-458
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Tidskriftsartikel (refereegranskat)abstract
- Frequencies of maxillary sinusitis in the population of the medieval town Sigtuna, Sweden, were examined. The first aim was to explore the occurrence of sinus conditions in this urban population, and the second was to investigate the effects of preservation in relation to these changes. The skeletal sample consisted of 274 adolescent and adult individuals buried ca 970-1530AD. The maxillary sinuses were examined for different types of skeletal change related to sinusitis. The severity and location of these changes were recorded, together with the preservation of the sinus. When the diagnostic criteria for bone preservation from previous studies was used, i.e. the preservation of at least one complete antral floor, the results showed that 97.7% (n=157) of the individuals were affected, with older individuals showing more severe bone changes. In the entire (i.e. more fragmented) sample, 94.5% (n=259) showed signs of sinusitis. Again, older individuals showed more severe bone changes, and males were more frequently affected. Also, an increased frequency over time was found. The maxillae were subdivided into groups of bone preservation, and the results showed that there was a significant relation between preservation and the registered presence and severity of sinusitis. The results may be used as a cautionary note against investigating the occurrence of maxillary sinusitis without considering the skeletal preservation factor. There was no correlation between preservation and sex or age groups. This suggests that the differences between younger and older and male and female were not a result of preservation alone and could be considered as trustworthy.
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| 21. |
- Sundman, E, et al.
(författare)
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Acetylcholine receptor density in human cricopharyngeal muscle and pharyngeal constrictor muscle
- 2002
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Ingår i: Acta Anaesthesiologica Scandinavica. - : Wiley. - 0001-5172. ; 46:8, s. 999-1002
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Tidskriftsartikel (refereegranskat)abstract
- Background: Upper esophageal sphincter resting tone is reduced during partial neuromuscular block, whereas contraction of the pharyngeal constrictor muscle is only slightly affected. We hypothesized that this difference may arise from differential nicotinic acetylcholine receptor (nAChR) density, the density supposedly being lower in the more sensitive cricopharyngeal muscle than in the resistant pharyngeal constrictor muscle. The aim of this study was to determine the density of nAChR in the main component of the upper esophageal sphincter, the cricopharyngeal muscle, and in the pharyngeal constrictor muscle. Methods: After approval by the institutional ethics committee and informed consent, muscle specimens were obtained from five patients undergoing surgery with laryngectomy for malignancies of the larynx or thyroid gland. None had received radiation therapy to the affected area. The nAChR from these tissue specimens were solubilized and incubated with I-125-alpha-bungarotoxin. The quantity of radioligand-receptor complex was measured by radioactive decay in a liquid scintillation counter. The receptor density was expressed as femtomoles per milligram of protein (fmol/mg protein). Results: The nAChR density was determined to 6.8 (3.5) fmol/mg protein (mean (SD)) in the cricopharyngeal muscle and 5.6 (2.1) fmol/mg protein in the pharyngeal constrictor muscle (P = 0.22). Although we could not find any difference in mean nAChR density, contrary to our hypothesis, the density in four of the five patients was higher in the cricopharyngeal muscle than in the pharyngeal constrictor muscle. Conclusion: Our results indicate that the density of nicotinic acetylcholine receptors is similar in the cricopharyngeal muscle and in the pharyngeal constrictor muscle. Nicotinic acetylcholine receptor density, as determined by I-125-alpha-bungarotoxin assay, cannot explain the difference in response to neuromuscular blocking drugs between the investigated muscles.
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| 22. |
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| 23. |
- Sundman, E, et al.
(författare)
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Neural control of the immune system
- 2014
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Ingår i: Advances in physiology education. - : American Physiological Society. - 1522-1229 .- 1043-4046. ; 38:2, s. 135-139
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Tidskriftsartikel (refereegranskat)abstract
- Neural reflexes support homeostasis by modulating the function of organ systems. Recent advances in neuroscience and immunology have revealed that neural reflexes also regulate the immune system. Activation of the vagus nerve modulates leukocyte cytokine production and alleviates experimental shock and autoimmune disease, and recent data have suggested that vagus nerve stimulation can improve symptoms in human rheumatoid arthritis. These discoveries have generated an increased interest in bioelectronic medicine, i.e., therapeutic delivery of electrical impulses that activate nerves to regulate immune system function. Here, we discuss the physiology and potential therapeutic implications of neural immune control.
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| 24. |
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| 25. |
- Sundman, E, et al.
(författare)
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The incidence and mechanisms of pharyngeal and upper esophageal dysfunction in partially paralyzed humans: pharyngeal videoradiography and simultaneous manometry after atracurium
- 2000
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Ingår i: Anesthesiology. - : Ovid Technologies (Wolters Kluwer Health). - 1528-1175 .- 0003-3022. ; 92:4, s. 977-977
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Residual neuromuscular block caused by vecuronium alters pharyngeal function and impairs airway protection. The primary objectives of this investigation were to radiographically evaluate the swallowing act and to record the incidence of and the mechanism behind pharyngeal dysfunction during partial neuromuscular block. The secondary objective was to evaluate the effect of atracurium on pharyngeal function. METHODS: Twenty healthy volunteers were studied while awake during liquid-contrast bolus swallowing. The incidence of pharyngeal dysfunction was studied by fluoroscopy. The initiation of the swallowing process, the pharyngeal coordination, and the bolus transit time were evaluated. Simultaneous manometry was used to document pressure changes at the tongue base, the pharyngeal constrictor muscles, and the upper esophageal sphincter. After control recordings, an intravenous infusion of atracurium was administered to obtain train-of-four ratios (T4/T1) of 0.60, 0.70, and 0.80, followed by recovery to a train-of-four ratio of more than 0.90. RESULTS: The incidence of pharyngeal dysfunction was 6% during the control recordings and increased (P < 0.05) to 28%, 17%, and 20% at train-of-four ratios 0.60, 0.70, and 0.80, respectively. After recovery to a train-of-four ratio of more than 0.90, the incidence was 13%. Pharyngeal dysfunction occurred in 74 of 444 swallows, the majority (80%) resulting in laryngeal penetration. The initiation of the swallowing reflex was impaired during partial paralysis (P = 0.0081). The pharyngeal coordination was impaired at train-of-four ratios of 0.60 and 0.70 (P < 0.01). A marked reduction in the upper esophageal sphincter resting tone was found, as well as a reduced contraction force in the pharyngeal constrictor muscles. The bolus transit time did not change significantly. CONCLUSION: Partial neuromuscular paralysis caused by atracurium is associated with a four- to fivefold increase in the incidence of misdirected swallowing. The mechanism behind the pharyngeal dysfunction is a delayed initiation of the swallowing reflex, impaired pharyngeal muscle function, and impaired coordination. The majority of misdirected swallows resulted in penetration of bolus to the larynx.
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