Evaluating cochlear implant trauma to the scala vestibuli

Objectives: Placement of cochlear implant electrodes into the scala vestibuli may be intentional, e.g. in case of blocked scala tympani or unintentional as a result of trauma to the basilar membrane or erroneous location of the cochieostomy. The aim of this study was to evaluate the morphological consequences and cochlear trauma after implantation of different cochlear implant electrode arrays in the scala vestibuli. Design: Human temporal bone study with histological and radiological evaluation. Setting: Twelve human cadaver temporal bones were implanted with different cochlear implant electrodes. Implanted bones were processed using a special method to section undecalcified bone. Main outcome measures: Cochlear trauma and intracochlear positions. Results: All implanted electrodes were implanted into the scala vestibuli using a special approach that allows direct scala vestibuli insertions. Fractures of the osseous spiral lamina were evaluated in some bones in the basal cochlear regions. In most electrodes, delicate structures of the organ of Corti were left intact, however, Reissner's membrane was destroyed in all specimens and the electrode lay upon the tectorial membrane. In some bones the organ of Corti was destroyed. Conclusions: Scala vestibuli insertions did not cause severe trauma to osseous or neural structures, thus preserving the basis for electrostimulation of the cochlea. However, destruction of Reissner's membrane and impact on the Organ of Corti can be assumed to destroy residual hearing.     

Time course of conscious and unconscious semantic brain activation

Event-related brain potentials (ERPs) were used to investigate the neurophysiological correlates of conscious and unconscious semantic processing. Masked words, which do not enter consciousness, as well as visible words, were shown to modulate the N400 ERP potential to subsequently presented, meaningfully related target words. The N400 is known as an electrophysiological index of semantic processing. However, for unconsciously perceived words semantic brain activation decays fast within 200 ms, but increases with time for consciously perceived words. Thus, conscious and unconscious semantic activation involves similar brain areas, but both forms of processes exhibit distinct, qualitatively different time courses.     

Pediatric emergency preparedness in the office

Pediatric office emergencies occur more commonly than is usually perceived by family physicians, and most offices are not optimally prepared to deal with these situations. Obtaining specific training in pediatric emergencies and performing mock "codes" to check office readiness can improve the proper handling of pediatric emergencies. Common airway emergencies include foreign-body aspiration and croup. Cool mist, racemic epinephrine nebulization and dexamethasone are typical treatment measures for croup. Asthma and bronchiolitis are common causes of respiratory distress. Hypovolemic shock is the most common cause of circulatory failure in children. Intraosseous access is a simple and underutilized route for vascular access in a critically ill child. Status epilepticus is the most common neurologic emergency. Avoidance of iatrogenic respiratory depression and hypotension can be optimized by taking an algorithmic approach to the use of anticonvulsant medications. Transport of patients after initial stabilization of an emergency should always be done in a manner that provides adequate safety and monitoring.     

Dual stimulation using corifollitropin alfa in 54 Bologna criteria poor ovarian responders – a case series

Research question

What are the reproductive outcomes of Bologna criteria poor responders undergoing dual stimulation (DuoStim) and subsequent cryopreserved embryo transfer?

In-plane motion correction for MR spectroscopic imaging

A motion-detection method is described that is specifically suited for MR spectroscopic imaging (MRSI) studies. Information on in-plane rotation and translation of the subject was obtained using external spatial reference markers that are uniquely identified via their chemical shift. The marker locations were obtained directly from the acquired data at each encoding step, and no additional data acquisition was required. This method was applied to brain ¹H MRSI studies that include subcutaneous lipid signals, which otherwise result in enhanced sensitivity to subject motion.     

Distal muscular dystrophy of Miyoshi type

Miyoshi myopathy (MM) is a rare distal myopathy that mainly occurs in Japan. And that is characterized by prominent involvement of the gastrocnemius muscles. Here we report two patients, brother and sister, from a German family. Onset of the disease was at the age of 20 and 22 years, respectively. In both siblings, there was an early and predominant involvement of the gastrocnemius muscles. Creatine kinase activity was elevated 37- to 95-fold above normal. Electromyography revealed fibrillations, positive sharp waves and a myopathic pattern, particularly in the distal muscles of the lower limbs. Histology of the gastrocnemius muscles showed myopathic changes consistent with muscular dystrophy. Occurrence in these two siblings but in no other family members was indicative of an autosomal-recessive inheritance. Our report indicates that MM may also be found in Germany, and that it should be considered in the differential diagnosis of distal myopathies. Received: 25 April 1996 Received in revised form: 26 July 1996 Accepted: 26 August 1996     

The Mechanism of Photoaffinity Labeling

Photoaffinity labeling is a recently introduced method for covalently binding chemical tags to the active sites of protein molecules, which is potentially capable of very great specificities of labeling. A labeling reagent is used that is converted by photolysis to an extremely reactive intermediate. According to the expected mechanism, the reagent molecules that are specifically and reversibly bound to the active site at the instant of photolysis react irreversibly in the site before they can dissociate from the site. In two such reagent-protein systems studied in this paper, however, it is shown that, while by the usual criteria photoaffinity labeling appears to have occurred, the expected mechanism in fact does not hold. This was discovered in experiments with scavengers present in the mixtures that were photolyzed. The general properties of, and criteria for, photoaffinity labeling reactions are discussed in the light of these findings.     

Addressing the childhood asthma crisis in Harlem: the Harlem Children's Zone Asthma Initiative

OBJECTIVES: We determined the prevalence of asthma and estimated baseline asthma symptoms and asthma management strategies among children aged 0-12 years in Central Harlem. METHODS: The Harlem Children's Zone Asthma Initiative is a longitudinal, community-based intervention designed for poor children with asthma. Children aged 0-12 years who live or go to school in the Harlem Children's Zone Project or who participate in any Harlem Children's Zone, Inc, program were screened for asthma. Children with asthma or asthma-like symptoms were invited to participate in an intensive intervention. RESULTS: Of the 1982 children currently screened, 28.5% have been told by a doctor or nurse that they have asthma, and 30.3% have asthma or asthma-like symptoms. To date, 229 children are enrolled in the Harlem Children's Zone Asthma Initiative; at baseline, 24.0% had missed school in the last 14 days because of asthma. CONCLUSION: The high prevalence of asthma among children in the Harlem Children's Zone Project is consistent with reports from other poor urban communities. Intensive efforts are under way to reduce children's asthma symptoms and improve their asthma management strategies.     

PAM cell assay as a tests for multiple-sclerosis associated agent.

Contrary to previous reports, no evidence for a multiple sclerosis-associated agent (MSAA) was obtained when coded brain samples from multiple sclerosis patients and controls were tested in PAM cells.     

Cochlear implantation with preservation of residual deep frequency hearing

BACKGROUND: The aim of the present paper is to evaluate the clinical parameters in patients implanted for combined, ipsilateral electric-acoustic stimulation of the auditory system. METHODS: A total of 18 patients with residual deep frequency hearing were implanted with a Combi 40+cochlear implant (MED-EL, Austria). Insertion depths ranged from 18 to 22 mm (360 degrees ). A modified surgical technique should contribute to hearing preservation in low frequency regions of the cochlea. Pure-tone audiometric thresholds were measured pre- and postoperatively. A speech audiometric evaluation was performed on two subjects. RESULTS: Utilizing adapted surgical procedures, the preservation of low frequency hearing was accomplished in 16 of 18 subjects (88.9%). Seven (38.9%) patients had complete and nine (50.0%) partial preservation of residual hearing. The speech discrimination scores of two patients documented an increase in sentence intelligibility when compared with only the cochlear implant. CONCLUSIONS: Hearing preservation in cochlear implant surgery is possible. Insertions of 360 degrees provide a full functioning cochlear implant to stimulate sufficient neural structures for above average discrimination scores with the implant alone. A synergistic effect of the electric and the acoustic stimulation modes leads to high discrimination scores in background noise.