Search results for "FN"
showing 10 items of 862 documents
Intrafamilial variability of the deafness and goiter phenotype in Pendred syndrome caused by a T416P mutation in the SLC26A4 gene.
2004
AbstractPendred syndrome (PS) is the most common cause of syndromic deafness, accounting for more than 5% of all autosomal-recessive hearing loss cases. It is characterized by bilateral sensorineural hearing loss and by goiter with or without hypothyroidism. Mutations in the SLC26A4 gene cause both classical PS and deafness associated with an enlarged vestibular aqueduct without goiter.To investigate a possible genotype-phenotype correlation in PS, we performed a detailed clinical and genetic study in three adult German sibs with typical PS caused by a common homozygous SLC26A4 mutation, T416P. An audiological long-term follow-up of 23 yr showed that the mutation T416P is associated with a …
Interaction between pre-landing activities and stiffness regulation of the knee joint musculoskeletal system in the drop jump: implications to perfor…
2002
The purpose of the present study was to investigate the interaction between the pre-landing activities and the stiffness regulation of the knee joint musculoskeletal system and the takeoff speed during a drop jump (DJ). Nine healthy male subjects performed a DJ test from the height of 50 cm. The surface electromyographic (EMG) activity of the vastus lateralis (VL) muscle was recorded to evaluate both the pre-landing and post-landing muscle activation levels. Simultaneous recording of the jumping motion and ground reaction force was performed by a high-speed video camera (100 frames x s(-1)), and a force platform was employed to allow joint moment analysis. Joint stiffness was calculated by …
In vivo mechanical response of human Achilles tendon to a single bout of hopping exercise
2010
SUMMARY Stiffness of the human Achilles tendon (AT) was determined in vivo before and after a single bout of hopping exercise. It was hypothesized, based on published data using in vitro specimens, that a reduction in AT stiffness may occur after just 1000 loading cycles at physiological stress levels. Ten healthy subjects performed two-legged hopping exercise consisting of 1150–2600 high impacts. Tendon stiffness was determined in several isometric ramp contractions [20%, 40%, 60%, 80% and 100% maximum voluntary contraction (MVC)] during which tendon elongation was measured using ultrasonography and two cameras. Tendon force was calculated by dividing measured ankle torque by magnetic reso…
Running in highly cushioned shoes increases leg stiffness and amplifies impact loading
2018
AbstractRunning shoe cushioning has become a standard method for managing impact loading and consequent injuries due to running. However, despite decades of shoe technology developments and the fact that shoes have become increasingly cushioned, aimed to ease the impact on runners’ legs, running injuries have not decreased. To better understand the shoe cushioning paradox, we examined impact loading and the spring-like mechanics of running in a conventional control running shoe and a highly cushioned maximalist shoe at two training speeds, 10 and 14.5 km/h. We found that highly cushioned maximalist shoes alter spring-like running mechanics and amplify rather than attenuate impact loading. T…
Postactivation potentiation can counteract declines in force and power that occur after stretching.
2016
Stretching can decrease a muscle's maximal force, whereas short but intense muscle contractions can increase it. We hypothesized that when combined, postactivation potentiation induced by reactive jumps would counteract stretch-induced decrements in drop jump (DJ) performance. Moreover, we measured changes in muscle twitch forces and ankle joint stiffness (KAnkle ) to examine underlying mechanisms. Twenty subjects completed three DJs and 10 electrically evoked muscle twitches of the triceps surae subsequent to four different conditioning activities and control. The conditioning activities were 10 hops, 20s of static stretching of the triceps surae muscle, 20s of stretching followed by 10 ho…
High-flow nasal cannula versus non-invasive ventilation for acute hypercapnic respiratory failure in adults: a systematic review and meta-analysis of…
2022
Abstract Background Non-invasive ventilation (NIV) with bi-level positive pressure ventilation is a first-line intervention for selected patients with acute hypercapnic respiratory failure. Compared to conventional oxygen therapy, NIV may reduce endotracheal intubation, death, and intensive care unit length of stay (LOS), but its use is often limited by patient tolerance and treatment failure. High-flow nasal cannula (HFNC) is a potential alternative treatment in this patient population and may be better tolerated. Research question For patients presenting with acute hypercapnic respiratory failure, is HFNC an effective alternative to NIV in reducing the need for intubation? Methods We sear…
The internal auditory artery: (embryology, anatomy, angiography, pathology).
1975
A review of the literature on the embryology, anatomy and angiography of the internal auditory artery has shown that there may be considerable variation as to the origin and number of internal auditory arteries. The present study, based on serial magnification angiographies of the internal auditory artery, has demonstrated 7 variants of the origin of this artery although in 45.4% of cases the internal auditory artery arose from the anterior inferior cerebellar artery. For the diagnosis of pathological processes in the cerebellopontine angle (tumors, sudden deafness, vascular abnormalities) magnification angiography is of special importance. Acoustic neurinomas in particular can be diagnosed…
Maternally inherited diabetes and deafness (MIDD): unusual occult exocrine pancreatic manifestation in an affected German family
2000
The mitochondrial (mt) 3243 DNA mutation is an underlying cause of maternally inherited diabetes and deafness (MIDD) syndrome and the syndrome of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS). We report an affected German MIDD pedigree with maternal lineage over three generations. The index patient, her mother, her maternal aunt and her maternal grandmother all suffered from diabetes and premature hearing loss and were positive on testing for the mt 3243 DNA mutation. The 27-year-old index patient had a history of grand mal seizures. As sequela of abdominal ultrasound and confirmed by magnetic resonance cholangio-pancreaticography, she was diagnose…
Mechanical efficiency of locomotion in females during different kinds of muscle action
1990
The mechanical efficiencies (ME) of pure positive and pure negative work as well as of stretch-shortening cycle (SSC) exercise were investigated with a special sledge apparatus. The subjects were 20 young females who performed six different types of submaximal exercise: two of pure concentric exercise (positive work), two of pure eccentric exercise (negative work) and two SSC exercises. The work intensities were determined individually, from the recordings of distance obtained during a single maximal concentric exercise. Each exercise involved 60 muscle actions lasting a total of 3 min per testing condition. The MEs of pure positive work with intensities of 30% and 60% maximum (C30 and C60 …
Effects of panel experience on olfactory memory performance: influence of stimuly familiarity and labeling ability of subjects
1996
This work attempted to define the impact of panel experience on olfactory memory performance by comparing scores in an odor recognition task obtained from a highly trained descriptive panel (17 subjects) and a naive one (33 subjects with no experience in sensory analysis). During the inspection phase, 16 odorants were presented monadically to subjects for familiarity rating and a written description. The recognition session was planned 7 days later with 32 odorants (including the 16 of the target set). Subjects also described the odor of the stimuli. The memory performance of each panel was estimated by the mean value of individual d' (index of detectability). Training of the descriptive pa…