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Mild Changes (mild + change)
Selected AbstractsImplications of different degrees of arytenoid cartilage abduction on equine upper airway characteristicsEQUINE VETERINARY JOURNAL, Issue 7 2008V. RAKESH Summary Reason for performing study: The necessary degree of arytenoid cartilage abduction (ACA) to restore airway patency at maximal exercise has not been determined. Objectives: Use computational fluid dynamics modelling to measure the effects of different degrees of ACA on upper airway characteristics of horses during exercise. Hypothesis: Maximal ACA by laryngoplasty is necessary to restore normal peak airflow and pressure in Thoroughbred racehorses with laryngeal hemiplegia. Methods: The upper airway was modeled with the left arytenoid in 3 different positions: maximal abduction; 88% cross-sectional area of the rima glottis; and 75% cross-sectional area of the rima glottis. The right arytenoid cartilage was maximally abducted. Two models were assumed: Model 1: no compensation of airway pressures; and Model 2: airway pressure compensation occurs to maintain peak airflow. The cross-sectional pressure and velocity distributions for turbulent flow were studied at peak flow and at different positions along the airway. Results: Model 1: In the absence of a change in driving pressure, 12 and 25% reductions in cross-sectional area of the larynx resulted in 4.11 and 5.65% reductions in peak airflow and 3.68 and 5.64% in tidal volume, respectively, with mild changes in wall pressure. Model 2: To maintain peak flow, a 6.27% increase in driving tracheal pressure was required to compensate for a cross-sectional reduction of 12% and a 13.63% increase in driving tracheal pressure was needed for a cross-sectional area reduction of 25%. This increase in negative driving pressure resulted in regions with low intraluminal and wall pressures, depending on the degree of airway diameter reduction. Conclusion: Assuming no increase in driving pressure, the decrease in left ACA reduced airflow and tidal volume. With increasing driving pressure, a decrease in left ACA changed the wall pressure profile, subjecting the submaximally abducted arytenoid cartilage and adjacent areas to airway collapse. Clinical relevance: The surgical target of ACA resulting in 88% of maximal cross-sectional area seems to be appropriate. [source] Environmental manipulations early in development alter seizure activity, Ih and HCN1 protein expression later in lifeEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2006Ulrich Schridde Abstract Although absence epilepsy has a genetic origin, evidence from an animal model (Wistar Albino Glaxo/Rijswijk; WAG/Rij) suggests that seizures are sensitive to environmental manipulations. Here, we show that manipulations of the early rearing environment (neonatal handling, maternal deprivation) of WAG/Rij rats leads to a pronounced decrease in seizure activity later in life. Recent observations link seizure activity in WAG/Rij rats to the hyperpolarization-activated cation current (Ih) in the somatosensory cortex, the site of seizure generation. Therefore, we investigated whether the alterations in seizure activity between rats reared differently might be correlated with changes in Ih and its channel subunits hyperpolarization-activated cation channel HCN1, 2 and 4. Whole-cell recordings from layer 5 pyramidal neurons, in situ hybridization and Western blot of the somatosensory cortex revealed an increase in Ih and HCN1 in neonatal handled and maternal deprived, compared to control rats. The increase was specific to HCN1 protein expression and did not involve HCN2/4 protein expression, or mRNA expression of any of the subunits (HCN1, 2, 4). Our findings provide the first evidence that relatively mild changes in the neonatal environment have a long-term impact of absence seizures, Ih and HCN1, and suggest that an increase of Ih and HCN1 is associated with absence seizure reduction. Our findings shed new light on the role of Ih and HCN in brain functioning and development and demonstrate that genetically determined absence seizures are quite sensitive for early interventions. [source] Alitretinoin in the treatment of hand eczemaFUTURE PRESCRIBER, Issue 2 2008Dr John English Consultant Dermatologist Hand eczema is an umbrella term for dermatoses of different clinical sub-types involving the hands. It varies in severity from mild changes affecting a few fingers to a severe blistering, itchy eruption involving the entire hand.1 Hand eczema has a major impact on earnings and quality of life, often resulting in repeated con-sultations, unemployment, time off work and interference with leisure activities.2,3 Copyright © 2008 John Wiley & Sons, Ltd. [source] Protective effects of melatonin against myocardial injury induced by isoproterenol in ratsJOURNAL OF PINEAL RESEARCH, Issue 2 2003Mahmut Acikel Abstract: This study was performed to determine whether melatonin could have a protective effect against myocardial injury (MI) induced by isoproterenol (ISO) in rats. Twenty-four rats were divided into three treatment groups: (1) control (n = 8): saline solution. (2) ISO (n = 8): ISO only. (3) melatonin + ISO (n = 8). Melatonin (10 mg/kg/day, i.p.) was administered 30 min before the initiation of ISO (150 mg/kg/day, s.c.). Drugs and saline were given at 14:00 hr for two consecutive days. At the end of the second day, blood samples were taken from the abdominal aorta shortly after the rats were anesthetized for the purpose of measuring cardiac troponins T (cTnT) and I (cTnI); hearts were removed, preserved and examined microscopically. Additionally, based on the histological changes in myocardial tissue, the rats were divided into three groups: no change, mild changes and moderate and/or marked changes. The mean cTnT and cTnI values were significantly increased in ISO group compared with control group [(1.29 ± 0.22 ng/mL versus 0.46 ± 0.07 ng/mL, P < 0.0001) and (0.56 ± 0.11 ng/mL versus 0.21 ± 0.01 ng/mL, P < 0.001)], respectively, and were significantly reduced in the ISO + melatonin group (0.65 ± 0.06 ng/mL for cTnT and 0.25 ± 0.01 ng/mL for cTnI) compared with the ISO only group (P < 0.01), respectively. cTnT and cTnI values were significantly increased in rats with moderate and/or marked cardiac changes compared with hearts where there were mild changes and no change (P < 0.05). ISO + melatonin group showed less histological changes than the ISO group (P < 0.01). In conclusion, this study revealed a protective effect of melatonin against ISO-induced MI in rats, and its potential clinical application in the treatment of MI. [source] Effect of streptozotocin on the ultrastructure of rat pancreatic isletsMICROSCOPY RESEARCH AND TECHNIQUE, Issue 5 2004M. Daisy Mythili Abstract Our objective was to study the effects of three (30, 40, and 50 mg/kg) doses of Streptozotocin (STZ) on fasting plasma glucose level (FPG) and observe its effects at the cellular level in rat pancreas by electron microscopy. FPG was measured in rats before induction of diabetes and then on 3, 7, and 14 days after induction of diabetes with STZ. Keto diastix urine strips were used to check urine glucose and ketone bodies. Two weeks after the induction of diabetes, the rat pancreas was removed and fixed for light and electron microscopic studies. Three days after induction, the mean FPG level was 112 mg/dl in Group I (30 mg/kg STZ), 217 mg/dl in Group II (40 mg/kg STZ), and 376 mg/dl in Group III (50 mg/kg STZ). Histology was normal in Group I but revealed altered islet structure in Groups II and III. Ultrastructure revealed intact D cells in all three groups. The focal mitochondria and Golgi complex swelling found in A and B cells was occasional in Group I and frequent in Groups II and III. Swelling of other organelles and reduction in the size and number of granules was further observed in Group III. It is our conclusion that the 30-mg/kg body weight STZ produces mild changes while 50 mg/kg proves to be fatal. STZ at 40 mg/kg has a moderate effect on plasma glucose as well as on the islets of Langerhans at a cellular level. Microsc. Res. Tech. 63:274,281, 2004. © 2004 Wiley-Liss, Inc. [source] Exploring the phonatory effects of external superior laryngeal nerve paralysis: An In vivo model,THE LARYNGOSCOPE, Issue 4 2009Nelson Roy PhD Abstract Objectives/Hypothesis: Little is known regarding the phonatory consequences of unilateral external superior laryngeal nerve (ESLN) paralysis. By selectively blocking the ESLN with lidocaine HCl (with laryngeal electromyography verification), we modeled acute, unilateral cricothyroid (CT) muscle dysfunction to explore possible acoustic, aerodynamic, auditory-perceptual and auto-perceptive effects. Study Design: Prospective, repeated measures, experimental design. Methods: Ten, vocally-normal adult males underwent lidocaine block of the right ESLN. Multiple measures of phonatory function across a variety of vocal tasks/conditions were acquired before and during the block using standard data acquisition and analysis protocols. Results: During ESLN block, phonatory frequency range was significantly reduced with compression of both upper and lowermost regions of the pitch range. Mean speaking fundamental frequency increased significantly during oral reading. Acoustic analysis, aerodynamic assessment, and auditory- perceptual evaluation by blinded listeners revealed modest increases in phonatory instability (jitter), increased laryngeal airway resistance with no objective evidence of glottic insufficiency, and mild deterioration in voice quality most evident during high pitched voice productions, respectively. Participants uniformly rated their speaking and singing voices as worse during the block with significant weakness, effort, and tightness that they perceived as a mild level of impairment. Conclusions: These data support generally mild changes to the speaking voice, which extend beyond reductions in pitch range only, and shed light on the potential untoward phonatory effects of acute, unilateral CT dysfunction. Laryngoscope, 2009 [source] | |||||||||||||