Chemosurgical debridement of osteomyelitic bone by zinc chloride fixative

Zinc chloride fixative (as described in fixed-tissue Mohs surgery) is useful as a chemical debridement method for osteomyelitic bone. We describe a case of an 86-year-old female with a 67-year history of an osteomyelitic ulcer of the anterior tibia. Previous attempts at surgical extirpation of the bone followed by immediate or delayed repair by orthopedic and plastic surgery services had eventuated in recurrence of the basic osteomyelitic process. Below-the-knee amputation was recommended as the only alternative to treatment. However, we chose to apply zinc chloride fixative which penetrated the full thickness of cortical bone and revealed a wider and deeper extent of the infectious process than previously recognized. Following removal of the fixed bone, a muscle flap repair followed by split-thickness skin grafting was done by plastic surgery. The patient remains ulcer and symptom free 31 months postoperatively. We feel zinc chloride fixative is useful as an adjunct to other surgical means of extirpation of bone as it is tissue sparing and more accurately determines the extent of involved bone when infected.     

Powered wheelchair bucking

Using a dummy test driver with a simulated flaccid forearm capable of representing either a large or zero friction condition, six powered wheelchairs were examined for bucking tendencies. In the zero friction condition, bucking was easily induced in 5 of 6 tested wheelchairs. Adding friction to the simulated forearm prevented bucking in all tested wheelchairs but one. Bucking is not simply related to wheelchair performance measures such as speed or acceleration. Sustained bucking corresponds to neutral stability in a speed regulated machine. Changes in natural frequency and damping characteristics are predicted as useful in reducing powered wheelchair bucking.     

Dopamine denervation does not alter in vivo 3H-spiperone binding in rat striatum: implications for external imaging of dopamine receptors in Parkinson's disease

Striatal particulate preparations, both from rats with lesion-induced striatal dopamine (DA) loss and from some striatal dopamine (DA) loss and from some patients with Parkinson's disease, exhibit increased 3H-neuroleptic binding, which is interpreted to be the mechanism of denervation-induced behavioral supersensitivity to dopaminergic compounds. After intravenous 3H-spiperone (3H-SP) administration to rats with unilateral nigral lesions, we found no differences in accumulation of total or particulate-bound 3H-SP in dopamine-denervated compared with intact striata. 3H-SP in vivo binds to less than 10% of striatal sites labeled by 3H-SP incubated with striatal particulate preparations in vitro. Quantitative autoradiography of 3H-SP binding to striatal sections in vitro also failed to reveal any effects of dopamine denervation. 3H-SP bound to striatal sites in vivo dissociates more slowly than that bound to striatal particulate preparations labeled in vitro. Striatal binding properties of 3H-SP administered in vivo are quite different from the same kinetic binding parameters estimated in vitro using crude membrane preparations of striatum. In addition, striatal binding of in vivo-administered 3H-SP is not affected by prior lesion of the substantia nigra, which results in profound ipsilateral striatal dopamine depletion. Thus, behavioral supersensitivity to dopaminergic compounds may not be associated with altered striatal binding properties for dopamine receptor ligands in vivo.     

Diagnosis of fetal hydronephrosis in utero using ultrasound

Detection of fetal hydronephrosis in utero, subsequent investigation, and surgical treatment is described. With the increasing use of ultrasound for obstetrical problems and greater experience with fetal sonography, more urologic abnormalities will be diagnosed prenatally.     

Nitrates do not affect prostacyclin formation by rat arteries: this is unrelated to increased vascular prostacyclin formation with age

The question of whether vasodilator nitrates act by releasing prostacyclin is controversial. Since the ability of blood vessels to form prostacyclin changes with age, we have investigated whether this may explain the discrepancies in the literature. It does not, since isosorbide dinitrate or glyceryl trinitrate incubated with rat aorta or vena cava from male Wistar rats had little or no effect on the release of prostacyclin, measured as 6-keto-PGF1 alpha. We confirm that the aorta produces substantially more prostacyclin than the vena cava. The arterial production of prostacyclin was greater in rats weighing 350-400 g than in those weighing 116-152 g, but the production by the veins was similar in both groups.     

Mohs micrographic surgery for skin cancers of the neck

The neck is not a common area for a skin cancer to occur. However, when it does occur and extends deeply, careful extirpation is necessary so that vital structures will be identified and, if possible, preserved. The Mohs surgeon can most accurately determine the true extent of malignancies in this area; the head and neck surgeon can best identify and protect important anatomic structures. Together both physicians can achieve the best chance of cure and lessen the complication rate for patients with selected invasive cutaneous tumors of the neck. Future collaborative efforts will undoubtedly be directed toward complete extirpation of deeper tumors of the neck, especially those of the pharynx, hypopharynx, and trachea.     

An investigation of the neuropsychological profile in adults with velo-cardio-facial syndrome (VCFS).

Velo-cardio-facial syndrome (VCFS) is associated with deletions on the long arm of chromosome 22, mild intellectual disability, poor social interaction and a high prevalence of psychosis. However, to date there have been no studies investigating the neuropsychological functioning of adults with VCFS. We compared 19 adults with VCFS with 19 age, gender and IQ matched controls using a comprehensive neuropsychological battery. Compared to controls, adults with VCFS had significant impairments in visuoperceptual ability (Visual Object and Space Perception Battery), problem solving and planning (Tower of London) and abstract and social thinking (Comprehension WAIS-R). It is likely that haploinsufficiency (reduced gene dosage) of a neurodevelopmental gene or genes mapping to chromosome 22q11 underlies the cognitive deficits observed in individuals with VCFS.     

Analog language teaching versus natural language teaching: Generalization and retention of language learning for adults with autism and mental retardation

Examined the effects of two instructional methods on language generalization and longterm retention in 23 adults with autism and severe to profound mental retardation. Analog language teaching employed discrete trials in a controlled setting concentrating on discrimination and identification of materials. Natural language teaching emphasized instruction through interactions that occurred incidentally to training students in the use of materials to perform functional tasks. Assessments were conducted under conditions favoring analog teaching to assure against partiality toward natural language teaching. Under such disadvantageous conditions, the methods of natural language teaching would be supported by results showing either no difference or an advantage in their favor. Both techniques increased initial and long-term generalization though the results suggest no relative superiority for either method under these assessment conditions. A significant interaction was found between prior functioning level and sequence of instruction. Because natural language teaching has many strengths, few drawbacks, and produces equal generalization and retention under disadvantageous conditions, it is strongly supported as preferable for people with autism and mental retardation.The authors acknowledge the important assistance provided by the following people: the staff and management of the Behavior Development and Learning Center at CSH/DC directed by Israel Perel, Lisa Kramer, Steve Hafferkamp, James Lowdermilk, and, finally, and especially, to the participants themselves.