Musculoskeletal manifestations of the Antley-Bixler syndrome

The Antley-Bixler syndrome is a rare disorder with many musculoskeletal anomalies that demand orthopedic assessment. The syndrome includes skeletal, craniofacial, and urogenital anomalies. The most common skeletal deformities are radiohumeral synostosis, craniosynostosis, multiple joint contractures, and arachnodactyly. Other orthopedic manifestations that may occur are femoral bowing, ulnar bowing, camptodactyly, synostoses of carpal and tarsal bones, clubfoot, vertebral body anomalies, perinatal fractures, and advanced skeletal age. The inheritance pattern is thought to be autosomal recessive. A patient with this syndrome is described, which is the 18th of 24 reports published in the world literature. This case is compared with the other reported cases.

An analysis of an air-ambulance program for children

Air-ambulance services are extremely expensive to operate and maintain. The value of their existence has been questioned in this era of rationalization and downsizing. We examined the cost, safety, flight crew composition, types of trauma, and effectiveness of our air-ambulance program at the Children's Hospital of Eastern Ontario (CHEO) over a 3-year period, 1994-1997. During this time, 392 children were aeroevacuated to CHEO, 113 surgical (29%), 136 medical (35%), and 143 neonates (36%). Of the surgical cases, 43% were transferred for orthopaedic trauma, the commonest being fractured femur, 23% for general surgical cases, most common being thoracoabdominal trauma, and 22% for neurosurgical reasons, most commonly basilar skull fractures. The average response time (time from which the call was received to the time when the helicopter reached the patient site) for all of the cases was 46 min. The average travel time (time from departure of patient site to arrival at CHEO) for these same cases was 25.59 min. The air-ambulance program for children in the Ottawa-Carleton Eastern Ontario areas, was found to be safe, effective, and allowed earlier specialized medical care to be provided.

Assessment of genetic changes in hepatocellular carcinoma by comparative genomic hybridization analysis: relationship to disease stage, tumor size, and cirrhosis

Hepatocellular carcinoma (HCC) is a common and highly malignant tumor that is prevalent in Southeast Asia. Although the etiological factors associated are now well recognized, the interactions between individual factors and the molecular mechanisms by which they lead to cancer remain unclear. Cytogenetic analysis on HCC has been limited because of poor hepatocyte growth in vitro. The recently developed technique of comparative genomic hybridization (CGH), however, permits screening of the entire genome without the need of cell culture. CGH was applied to the study of genomic aberrations in 67 surgically resected samples of HCC, 3 of adenomatous hyperplasia (AH), and 12 of nontumorous cirrhotic liver surrounding the tumors. All samples were from patients of a racially and etiologically homogeneous population in Southern China, where chronic hepatitis B virus infection is the main etiological factor. CGH analysis of the HCC samples revealed frequent copy number gain of 1q (48/67 cases, 72%), 8q (32/67 cases, 48%), 17q (20/67 cases, 30%), and 20q (25/67 cases, 37%) and common losses on 4q (29/67 cases, 43%), 8p (25/67 cases, 37%), 13q (25/67 cases, 37%), and 16q (20/67 cases, 30%). Our finding of a high incidence of 1q gain strongly suggested this aberration was associated with the development of HCC. Genomic abnormalities were detected in 1 of the 3 AH specimens but absent in all 12 cirrhotic tissues surrounding the tumor. Clinical staging classified 3/67 HCC cases as T1, 53 cases as T2, and 11 cases as T3. No significant difference in the pattern of genomic imbalances was detected between stages T2 and T3. A significant copy number loss of 4q11-q23 was, however, identified in those tumors larger than 3 cm in diameter. Of particular interest was the identification of 8q copy number gain in all 12 cases of HCC that arose in a noncirrhotic liver, compared with only 20/55 cases in HCC arising in a cirrhotic liver. We suggest that 8q over-representation is likely associated with a growth advantage and proliferative stimulation that have encouraged malignant changes in the noncirrhotic human liver.

Periosteal augmentation of the acetabulum

The periosteum in children and especially infants has significant osteogenic potential. To determine the efficacy of periosteal flaps to assist in improving acetabular coverage in children with acetabular dysplasia, a series of experiments were designed using young rabbits. Three groups of five rabbits each had periosteal flaps fashioned and brought down from the anterolateral aspect of the innominate bone superior to the acetabulum and sutured to the capsule of the hip. The study was designed to examine the effects of the periosteal cambium layer in the formation of new bone to augment the acetabulum and to determine the effects of a periosteal flap plus cancellous bone graft. A control group of five rabbits underwent a sham operation of an open arthrotomy of the hip. Radiographic and histologic examination at 12 weeks revealed augmentation of the acetabulum with periosteal flaps that resulted in an average improvement of the acetabular index of 3.5 degrees and 6.6 degrees, without and with bone graft, respectively. New bone formation from the rim of the acetabulum averaged 3.9 mm with periosteal flaps alone and 4.6 mm with bone graft added. Periosteal augmentation of the acetabulum in conjunction with established procedures for augmenting acetabular coverage would appear to be a useful procedure for improving coverage of the femoral head in children with acetabular dysplasia.

The influence of desmopressin on blood loss during spinal fusion surgery in neuromuscular patients

STUDY DESIGN

A double-blind study comparing the effects of desmopressin and a placebo (normal saline) on blood loss during spinal instrumentation for neuromuscular scoliosis.

OBJECTIVE

To determine the effectiveness of desmopressin acetate (DDAVP) in reducing operative blood loss in hemostatically normal patients undergoing spinal fusion surgery for neuromuscular scoliosis.

SUMMARY OF BACKGROUND DATA

Desmopressin acetate has been shown to improve bleeding times and to provide surgical hemostasis in patients with platelet disorders. Its effect in reducing bleeding times in normal patients has been the subject of debate in several surgical specialties. Recent observations that DDAVP seems to reduce bleeding times and blood loss in patients undergoing spinal surgery for neuromuscular scoliosis warranted a more focused analysis on its role in this surgical procedure.

METHODS

Patients undergoing surgery for neuromuscular scoliosis were randomly assigned to receive DDAVP or placebo. Bleeding times and plasma clotting factors were measured before the administration of the DDAVP or placebo and 60 minutes after. Operative blood loss was carefully measured.

RESULTS

Although the administration of DDAVP decreased overall blood loss by an average of 19% compared with blood loss in the placebo group and blood loss per vertebra fused by an average of 15%, these results were not statistically significant.

CONCLUSIONS

Bleeding time and blood loss seem to respond better to DDAVP in some patients, in whom significant decreases were observed, than they do in others. The problem is in identifying those patients in whom a decrease in bleeding time will be elicited after administration of DDAVP. Preoperative administration of DDAVP to such patients should significantly decrease operative blood loss.

The glycaemic index of foods containing sugars: comparison of foods with naturally-occurring v. added sugars

The primary aim of the present study was to expand the glycaemic index (GI) database by determining the GI and insulin index values of thirty-nine foods containing sugars in healthy adults. The second aim was to examine the hypothesis that glycaemic and insulin responses to foods which contain added sugar(s) are higher than responses to foods containing naturally-occurring sugars. Eight healthy subjects drawn from a pool of eighteen consumed 50 g carbohydrate portions (except 25 g carbohydrate portions for fruits) of the test foods. The GI and insulin index were determined according to standardized methodology and expressed on a scale on which glucose = 100. The median GI and insulin index values of all foods tested were 56 (range 14 to 80) and 56 (range 24 to 124) respectively. The median GI of the foods containing added sugars was similar to that of foods containing naturally-occurring sugars (58 v. 53 respectively, P = 0.08). Likewise, the median insulin index of the foods containing added sugars was not significantly different from that of foods containing naturally-occurring sugars (61 v. 56 respectively, P = 0.16). There was no evidence of 'rebound hypoglycaemia' or excessive insulin secretion relative to the glucose response. We conclude that most foods containing sugars do not have a high GI. In addition, there is often no difference in responses between foods containing added sugars and those containing naturally-occurring sugars.

Parosteal fasciitis in children

Parosteal fasciitis is a pseudosarcomatous benign lesion of fibrous tissue that has often been confused with malignancy. The purpose of this study was to document the clinical and pathological features of four children with this condition and compare the results with the world literature. The ages of the patients whose cases were reviewed ranged from 9 to 15 years. There were three girls and one boy. All the lesions occurred in the lower extremities, and histologically were characterized by a fibroblastic proliferation with inflammatory cells, diffuse capillary network, and varying quantities of metaplastic bone. All patients were treated by local excision of the lesion. One child had a recurrence of the lesion requiring another surgical removal. A set of clinicopathological criteria has been formulated for the diagnosis of parosteal fasciitis in children. Parosteal fasciitis is uncommon in children but manifests the same clinicopathological features as the adult lesion.

Prostaglandin-induced neonatal periostitis

Prostaglandins are being commonly used to maintain the patency of the ductus arteriosus in infants with congenital ductal-dependent heart disease. A significant and unusual side effect of this drug treatment is the symmetrical development of periostitis of the long bones. A review of neonates with congenital heart disease requiring prostaglandin treatment at the Children's Hospital of Eastern Ontario revealed five infants who developed periostitis, the earliest onset being after 14 days of prostaglandin infusion. The drug dosage varied in these infants from 0.02 to 0.10 micrograms/kg/min. The periostitis was associated with limb pain and considerable swelling of the extremities in all children. The periostitis improved on cessation of the prostaglandin infusion, and by 6 weeks after the cessation of the drug, the periostitis had decreased significantly. Periostitis seemed more dependent on the duration of administration of the prostaglandin than on the dosage of prostaglandin administered. Awareness of this entity is essential not only for the treatment team caring for these infants but also for consultant pediatric orthopaedists to avoid excessive investigation for infection, metabolic disease, or vitamin deficiencies that resemble prostaglandin-induced periostitis.

Discriminating the effects of triazolam on stimulus and response processing by means of reaction time and P300 latency

The benzodiazepines slow information processing and the sites of this slowing were mapped using the Additive Factors Method in combination with the P300 component of the event-related brain potential. It was assumed that P300 largely reflects the time to evaluate a stimulus while reaction time (RT) reflects this time plus the time to select and execute a response. Twelve subjects were administered 0.25 mg triazolam in a repeated measures single-blind design. A visual 80-20% oddball task was used in which stimulus intensity and signal quality were manipulated with accuracy of responding held constant at a high level. RT and EEG data were collected simultaneously and the P300 elicited by the low probability stimuli was measured on a single trial basis. Triazolam slowed RT (172 ms, P < 0.0003) more than P300 (88 ms, P < 0.0007), but both measures exhibited a drug x stimulus intensity interaction. RT also exhibited a drug x signal quality interaction but P300 did not. These results suggest that triazolam has selective effects on perceptual processing by slowing an early pre-processing stage but not a later feature extraction stage. In addition, the drug appears to slow some aspect of response processing. This evidence is taken as support for a multiple process rather than a general sedation view of benzodiazepine effects on stages of processing.

A survey of ciguatera: assessment of Puako, Hawaii, associated with ciguatera toxin epidemics in humans

A survey for the assessment of the ciguatera problem has been determined in Puako, South Kohala, on the Island of Hawaii. This is in the area of persistent ciguateric outbreaks during the months of January through March, caused by a specific species of fish (Cheilinus rhodochrous, red rose wrasse, or po'ou). Analyses of algae, Gambierdiscus toxicus, and various species of fish, including herbivores and carnivores, gave positive indications of Puako as a potential ciguateric area. Algae associated with Gambierdiscus toxicus blooms and the dinoflagellate itself were found in transects A and D. Transects A and D showed 291 G. toxicus per gram of Tolycarpidia glomurata and 9 G. toxicus per gram of Turbinaria sp. with epiphytic Jania sp., respectively. No G. toxicus was found in transects B and C. This may be attributed to the low salinity from intrusion of freshwater in this vicinity. Examinations of the fish, kole, manini, Hawaiian kole, roi, and po'ou by the solid-phase immunoassay showed 89% of fish in the borderline and positive categories from all transects. Extracts of viscera and flesh showed high levels of toxicity in mouse (13 of 23 deaths), particularly in the viscera (gut) of both herbivores and carnivores. The guinea pig atrial analysis generally showed a few ciguatoxin-like, but most were nonciguateric type responses. The data presented in this Puako survey showed evidence of toxic fish associated with ciguatoxin-like and most probably other toxins, either polyethers or non-polyethers as yet unidentified.

Rice: a high or low glycemic index food?

We determined the glycemic (GI) and insulin-index (II) values for 12 rice products, using eight healthy subjects. The products were brown and white versions of three commercial varieties of rice [two varieties with normal amylose content (20%) and the other with 28% amylose], a waxy rice (0-2% amylose), a converted rice, a quick-cooking brown rice, puffed rice cakes, rice pasta, and rice bran. The GI of the rices ranged from 64 +/- 9 to 93 +/- 11, where glucose = 100. The high amylose rice gave a lower GI and II (P < 0.01) than did the normal-amylose and waxy-rice varieties. The converted rice and most other rice products gave a high GI. Insulin indices correlated positively with GI (r = 0.75, P < 0.05), although they were lower than expected. These results indicate that many varieties of rice, whether white, brown, or parboiled, should be classified as high GI foods. Only high-amylose varieties are potentially useful in low-GI diets.

Elevated plasma vitamers of vitamin B6 in patients with chronic renal failure on regular haemodialysis

Plasma pyridoxal-5'-phosphate (PL-5'-P), pyridoxal (PL), pyridoxine (PN), and 4-pyridoxic acid (4-PA) were measured by high-performance liquid chromatography (HPLC) in 39 patients (15 male, 24 female) with chronic fenal failure undergoing regular haemodialysis and 46 healthy controls (28 male, 18 female). All three vitamers of vitamin B6 and the metabolite were significantly elevated in the haemodialysis patients. Mean PL-5'-P and PN concentrations were 20 times the mean in controls. Only one patient took a vitamin B6 supplement. In view of the neurotoxicity of supranutritional intakes of PN in normal humans we suggest that supplements of PN be carefully monitored when administered to patients with chronic renal failure.

Persistent changes in the fatty acid composition of erythrocyte membranes after moderate intake of n-3 polyunsaturated fatty acids: study design implications

To examine the incorporation of n-3 polyunsaturated fatty acids (PUFAs) into erythrocyte membranes during and after moderate n-3 PUFA intake, 12 healthy men were fed three diets for 6-wk periods in a 3 x 3 crossover design, supplying different amounts of eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3): a control diet, a fish diet (0.15 g EPA/d, 0.41 g DHA/d), and a fish + oil diet (5 g fish oil/d; 0.99 g EPA/d and 0.99 g DHA/d). A 6-wk washout period was allowed between diets. Between 6 and 12 wk after the fish + oil diet, erythrocyte EPA and DHA were still declining and it was only after 18 wk that erythrocyte EPA had returned to baseline whereas DHA had not. Investigators examining variables that are influenced by altered membrane fatty acid composition should be aware of these prolonged effects when designing studies. Protracted washout periods (greater than 18 wk) make the classic crossover design prohibitive and a parallel design becomes essential.

Erythrocyte eicosapentaenoic acid versus docosahexaenoic acid as a marker for fish and fish oil consumption

The fatty acid composition of erythrocyte membranes was investigated in 21 healthy men after 6 wk of varying intakes of eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3). In one experiment, 12 subjects were fed three diets in a 3 x 3 crossover design: an essentially fish-free control diet, a fish diet (0.15 g EPA/d, 0.41 g DHA/d) and the same fish-based diet supplemented with 5 g/d fish oil (Fish + Oil: 0.99 g EPA/d, 0.99 g DHA/d). A 6 wk wash-out period was allowed between each diet. In another experiment, 11 subjects were supplemented with 5 g/d fish oil alone for 6 wk (0.84 g EPA/d, 0.48 g DHA/d). After fish or fish oil feeding, the percent proportion of EPA and DHA in the erythrocyte membranes rose at the expense of linoleic and arachidonic acids. After 6 wk on the fish-based diets, EPA incorporation approached saturation, with the incremental increases being proportional to the amounts supplied by the diets. In contrast, parallel increases were observed for erythrocyte DHA even though the Fish + Oil diet was supplying twice as much DHA as the fish alone diet. These observations imply different metabolic rates for EPA and DHA and their importance is discussed in terms of the value of erythrocyte EPA versus DHA as markers for fish and fish oil consumption.

The use of psychometric tests in the evaluation of patients presenting for orthognathic surgery--a preliminary report

Psychological evaluation in some orthognathic patients may be necessary as the psychosocial stress of the deformity may lead to psychiatric morbidity such as depression or paranoid disorders. It is also possible for patients with underlying psychosis to present first to the dental surgeon for jaw correction. The use of several psychological tests appropriate for patients presenting with dentofacial deformities is discussed. Nine patients with skeletal malocclusions who were referred for psychiatric assessment are reported here. Three case vignettes are included to give an impression of the type of clinical situations where such an assessment may be helpful.

Gallium scan as a prognostic indicator in neuroblastoma

Gallium-67 scan results were correlated with the long-term clinical course in ten children with neuroblastoma. The four patients whose primary tumor did not accumulate gallium have exhibited a significantly better survival time (mean duration 68.2 months) as compared to the six patients with gallium-positive tumors (mean duration 16.6 months, P < 0.001). This difference in survival was not explainable on the basis of accepted prognostic indicators, such as age of patient or stage of disease at initial diagnosis. These results indicate that gallium uptake may be a useful prognostic indicator in children with neuroblastoma, independent of other variables.

Scintigraphic evaluation of childhood malignancies by 67Ga-citrate

The utility and limitations of 67Ga scintigraphy in children with solid tumors were evaluated. Thirty-five patients with malignancies (13 lymphoreticular neoplasms, 11 soft-tissue sarcomas, 8 neuroblastomas, and 3 primary bone tumors) had a 67Ga-citrate scan as part of their clinical evaluation. The sensitivity and specificity of the test were analyzed for the different tumor types. The overall sensitivity of the 67Ga-citrate scan for the lymphoma group was 87%. Higher values were obtained for the mediastinal and abdominal regions. Ninety-three per cent of the involved sites were correctly identified by 67Ga scintigraphy in the soft-tissue sarcoma group. Small lung metastases, however, were missed on scan. Thus, 67Ga scans should be complemented with chest radiographs and whole chest tomograms for both initial evaluation and follow-up in those patients. 67Ga had low sensitivity for neuroblastoma.