Vitamin D, bone mineral density and risk of fracture in people with intellectual disabilities.

BACKGROUND: People with intellectual disabilities (IDs) have very high rates of osteoporosis and fractures, to which their widespread vitamin D deficiency and other factors could contribute. We aimed to assess in people with IDs previously treated for vitamin D deficiency (1) long-term adherence to vitamin D supplementation and (2) bone mineral density (BMD), as an indicator for risk of fractures, according to vitamin D supplementation and other factors. METHOD: We recorded height, weight, medical, pharmacological, dietary and lifestyle assessment. Blood sample were taken for vitamin D and related analytes. dual-energy X-ray absorptiometry for BMD was performed. RESULTS: Of 51 study participants (mean [standard deviation, SD] age 51.5 [13.6] years, 57% male), 41 (80.4%) were taking vitamin D and 10 were not. Mean [SD] serum vitamin D was 81.3 [21.3] vs. 25.2 [10.2] nmol/L (P < 0.0001), respectively. Thirty-six participants underwent a dual-energy X-ray absorptiometry scan, which showed osteoporosis in 23.7% and osteopenia in 52.6%. Participants on vitamin D had higher BMD than those who were not, a statistically significant difference when confounders (lack of mobility and hypogonadism) were removed. BMD was significantly different according to mobility, particularly in wheelchair users, in whom hip BMD was 33% lower (P < 0.0001) than in participants with normal mobility. Participants still taking vitamin D showed a 6.1% increase in BMD at the spine (P = 0.003) after mean [SD] 7.4 [1.5] years vitamin D treatment. CONCLUSIONS: In people with IDs and previous vitamin D deficiency, BMD increases on long-term vitamin D supplementation. However, additional strategies must be considered for osteoporosis and fracture prevention in this population.

Biology undergraduates' misconceptions about genetic drift.

This study explores biology undergraduates' misconceptions about genetic drift. We use qualitative and quantitative methods to describe students' definitions, identify common misconceptions, and examine differences before and after instruction on genetic drift. We identify and describe five overarching categories that include 16 distinct misconceptions about genetic drift. The accuracy of students' conceptions ranges considerably, from responses indicating only superficial, if any, knowledge of any aspect of evolution to responses indicating knowledge of genetic drift but confusion about the nuances of genetic drift. After instruction, a significantly greater number of responses indicate some knowledge of genetic drift (p = 0.005), but 74.6% of responses still contain at least one misconception. We conclude by presenting a framework that organizes how students' conceptions of genetic drift change with instruction. We also articulate three hypotheses regarding undergraduates' conceptions of evolution in general and genetic drift in particular. We propose that: 1) students begin with undeveloped conceptions of evolution that do not recognize different mechanisms of change; 2) students develop more complex, but still inaccurate, conceptual frameworks that reflect experience with vocabulary but still lack deep understanding; and 3) some new misconceptions about genetic drift emerge as students comprehend more about evolution.

Active learning not associated with student learning in a random sample of college biology courses.

Previous research has suggested that adding active learning to traditional college science lectures substantially improves student learning. However, this research predominantly studied courses taught by science education researchers, who are likely to have exceptional teaching expertise. The present study investigated introductory biology courses randomly selected from a list of prominent colleges and universities to include instructors representing a broader population. We examined the relationship between active learning and student learning in the subject area of natural selection. We found no association between student learning gains and the use of active-learning instruction. Although active learning has the potential to substantially improve student learning, this research suggests that active learning, as used by typical college biology instructors, is not associated with greater learning gains. We contend that most instructors lack the rich and nuanced understanding of teaching and learning that science education researchers have developed. Therefore, active learning as designed and implemented by typical college biology instructors may superficially resemble active learning used by education researchers, but lacks the constructivist elements necessary for improving learning.

Diagnostic Criteria for Psychiatric Disorders for Use with Adults with Learning Disabilities/Mental Retardation (DC-LD) and the diagnosis of anxiety disorders: a review.

BACKGROUND/METHODS: During the development of Diagnostic Criteria for Psychiatric Disorders for Use with Adults with Learning Disabilities[DC-LD] a literature review of diagnostic issues in anxiety disorders in adults with intellectual disability (ID) was undertaken using electronic and hand searching of journals. RESULTS: Relevant general concepts in the general population are reviewed briefly before those related specifically to adults with ID. The literature relating to the diagnosis of specific anxiety disorders is reviewed, although with the exception of obsessive compulsive disorder this consists mainly of case reports. Difficulties in the use of diagnostic systems developed for the general population for the diagnosis of anxiety disorders in adults with ID are frequently commented upon. CONCLUSIONS: It is concluded that anxiety disorders are well recognized in adults with ID, although their prevalence is uncertain, and that the use of modified diagnostic criteria may aid further research in this area.

A descriptive survey of long-term residents with epilepsy and intellectual disability at the Chalfont Centre: is there a relationship between maladaptive behaviour and magnetic resonance imaging findings?

The advent of high-resolution magnetic resonance imaging (MRI) has facilitated the identification of subtle, aetiologically relevant structural brain abnormalities in a significant proportion of patients with epilepsy and negative standard neuro-imaging. In the present study of people with intellectual disability (ID), the authors show that a high frequency of cerebral structural abnormalities (72.4%) can be demonstrated by high-resolution MRI in patients with epilepsy and ID. Malformations of cortical development (MCD) were found in 8.7% of people without profound ID. An earlier age of onset of habitual seizures was associated with more severe ID and more severe seizures in adulthood. There was no obvious association between this finding and maladaptive behaviour, but a past history of febrile convulsions was associated with increased irritability and agitation. Since there was no obvious association between a history of febrile convulsions and MRI abnormalities, the reason for the above finding remains unclear. Inevitably, any residential epilepsy centre population is subject to selection biases. The population studied was highly skewed, with only one-third of the sample being female and 80% having mild ID. Thus, the findings of the present study cannot necessarily be generalized to all people with ID.

Information processing in anxiety: a pilot study of the effect of manipulating 5-HT function.

We gave the indirect 5-HT agonist, D-fenfluramine (30 mg), the 5 -HT antagonist methysergide (2 mg) and placebo to 11 patients with an anxiety disorder and 12 controls in a double-blind, balanced-order, cross-over design. Compared to controls, patients had significantly higher anxiety ratings, were slower in naming colours in computerized Stroop tests and showed greater interference for anxiety-related words. Patients tended to have a lower critical flicker fusion threshold (CFFT) than controls and in the subjects taken as a whole there was a significant inverse correlation between CFFT and Spielberger state (r=-0.54, p<0.01) and trait anxiety (r=-0.55, p<0.01). Neither drug had significant effects on anxiety ratings or on Stroop interference. D-Fenfluramine significantly increased CFFT (p < 0.02) and methysergide non-significantly reduced CFFT with no significant differences between patients and controls. 5-HT may be involved in lower-level visual information processing but we found no evidence for its direct involvement in the attentional bias for anxiety-related information in the emotional Stroop.

Alternatives in the management of aneurysmal bone cysts of the mandible.

Aneurysmal bone cyst (ABC) is an unusual expansile lesion of bone which may arise within the mandible on rare occasions. This lesion may arise with very few signs or symptoms. Surgical treatment consists of complete excision or curettage. The recurrence rate may be high in lesions which are incompletely excised. Three cases of aneurysmal bone cysts in children will be presented, demonstrating the wide variation of clinical presentation. One case required an extensive mandibular resection, necessitating the first reported microvascular mandible reconstruction for this entity in a pediatric patient.

Tracheoplasty for congenital complete tracheal rings.

OBJECTIVE: To better appreciate the complex nature of the pediatric patient with tracheal stenosis due to congenital complete tracheal rings, we evaluated clinical presentation, methods of evaluation, necessity for surgical repair, associated anomalies, and outcome. DESIGN: Retrospective study. PATIENTS: Eighteen patients with long-segment tracheal stenosis due to congenital complete tracheal rings were evaluated at Cincinnati (Ohio) Children's Hospital Medical Center between 1985 and 1991. Three patients did not require surgical intervention. Fifteen patients underwent tracheoplasty with cardiopulmonary bypass through a midline sternotomy. RESULTS: The patients with congenital complete tracheal rings usually present with respiratory compromise in the first year of life. In the majority of patients, a diagnosis was made based on the symptoms and findings of an endoscopic examination with the aid of plain film roentgenography. In selected patients, computed tomography or magnetic resonance imaging was used. We evaluated symptoms, length of stenosis, type of repair, duration of intubation, and complications, as well as the mortality associated with this procedure. CONCLUSIONS: The technique of tracheoplasty has evolved at our institution, including the use of a posterior tracheal division, anterior castellated division, autologous pericardial patch grafting, and cricoid split with intubation for 7 to 21 days. We found the mortality associated with this procedure quite high at 47%, compared with previously published reports with mortality figures between zero and 77%.

Primary mucinous adenocarcinoma of the eyelid.

Primary mucinous adenocarcinoma of the skin is a rare entity arising from eccrine sweat glands with a propensity for local recurrence and metastasis. This tumor has been widely reported in the ophthalmology literature, but not to our knowledge in the otolaryngology literature. A case of a 48-year-old man with a mucinous adenocarcinoma extensively involving the right eyelid and orbit necessitating craniofacial resection is presented together with a discussion of the pathology, clinical features, and management.

The role of computed tomography in the diagnosis of subperiosteal abscess of the orbit.

Periorbital cellulitis is a frequent complication of sinusitis in children. Subperiosteal abscess (SPA), however, is an uncommon sequela and may lead to serious complications if not promptly and adequately treated. A series of 13 consecutive patients who underwent orbital computed tomographic (CT) scans from January 1, 1986, to June 30, 1989, to investigate the possibility of SPA were reviewed. As demonstrated in this series, the diagnosis of subperiosteal abscess remains a clinical one that may be supported, but not determined, by an orbital CT scan. Cautious interpretation of these studies is advocated. Aggressive surgical therapy in appropriate clinical situations will lead to more rapid resolution of the disease process and fewer complications.

Complications of adenotonsillectomy in children under 3 years of age.

Adenotonsillectomy in children may be performed safely on an outpatient basis in the majority of cases without an increase in complication rates. However, very young children comprise a unique patient subpopulation with regard to adenotonsillar surgery. Surgical indications in older children tend to be dominated by chronic recurrent infections, whereas younger children usually require surgery for chronic upper airway obstruction related to adenotonsillar hypertrophy. This study was undertaken to evaluate the adenotonsillectomy patient population under 3 years of age. Complication rates related to airway problems, hemorrhage, and dehydration were determined. Children under 3 years of age demonstrated an increased incidence of postoperative airway complications, manifested by oxygen desaturation and transient upper airway obstruction. It is recommended that adenotonsillectomy be performed on such patients on an inpatient basis with close postoperative monitoring including pulse oximetry.

Abnormalities of the bony thorax causing tracheobronchial compression.

A number of intrathoracic and extrathoracic causes of airway obstruction have been well documented in the literature. At times, tracheal compression may be caused by abnormalities of the bony thorax whose previously unrecognized significance can result in unexpected difficulties when extubation is attempted following a routine intubation. Alternatively, patients may develop progressive distress secondary to their skeletal abnormalities. We report on cases illustrating anomalies of the manubrium, sternum and spine which have caused significant, occasionally life-threatening, tracheal and bronchial narrowing including pectus excavatum and scoliosis. A protocol is presented detailing the appropriate methods of diagnosis and treatment of these types of deformities.

Alteration of colony-stimulating factor output, endotoxemia, and granulopoiesis in cyclic neutropenia.

Cellular and humoral factors involved in the regulation of granulopoiesis were evaluated in two patients with cyclic neutropenia by utilizing the agar-gel marrow culture technique to serially study marrow granulocytic colony-forming capacity (CFC) and the urinary output of colony-stimulating factor (CSF). CSF output varied inversely with peripheral neutrophil counts and directly with monocyte counts and evidence for infection (endotoxemia and/or staphylococcal abscesses). Following autologous infusion of one patient's plasma obtained during a period of neutropenia, increased urinary excretion of CSF occurred concomitant with increments in both marrow CFC and the proportion of granulocytic progenitor cells in DNA synthesis. Neutrophil periodicity was not altered by the administration of the neutropenic plasma. These findings are consistent with the hypothesis that cyclic neutropenia is caused by a quantitatively decreased entry of stem cells or granulocytic progenitor cells into granulopoiesis.

An investigation of the location and possible compartmentation of the precursor pool of phenylalanine for protein synthesis in human granulocytes.

Evidence is presented that in human granulocytes the immediate precursor pool of phenylalanine for protein synthesis in vitro is intracellular significant compartmentation.

Muscle fibre type changes in hypothyroid myopathy.

Changes in muscle fibre type in hypothyroid myopathy were studied by serial percutaneous needle biopsy of vastus lateralis before and during treatment with L-thyroxine. A type II fibre atrophy and loss was found, which correlated with the clinical and biochemical evidence of a myopathy. The type II fibre atrophy was corrected by L-thyroxine but type II fibre loss was still apparent in severely myopathic patients up to two years after starting treatment. The pathogenesis and significance of type II fibre atrophy and loss are discussed in relation to prognosis.