A comparison between bipedal and quadrupedal rats: do bipedal rats actually assume an upright posture?

STUDY DESIGN: A basic science animal investigation. OBJECTIVES: To determine if bipedal rats differ in upright posture compared with quadrupedal rats. SUMMARY OF BACKGROUND DATA: It has been reported that surgically induced bipedalism in the rat leads to habitual upright posture. Based on this finding, bipedal rats have been used to study the changes erect posture induces in bone, ligament, muscle, and intervertebral discs. Previous studies have used direct observation as a means to describe posture. This study is the first to quantify postural differences between bipedal and quadrupedal rats. METHODS: Eleven bipedal rats were created by forelimb and tail amputation within 24 hours of birth. Eleven quadrupedal rats served as controls. Specialized cages were used with infrared sensors, and a computer program measured the total amount of time in the upright stance, the number of stands, and the amount of horizontal movement in the upright stance. Statistical comparisons were made between bipedal and quadrupedal rats hourly and over a 24-hour period of time. RESULTS: Quadrupedal rats assumed an upright posture for a significantly greater amount of time than bipedal rats when monitored over 24 hours (P = 0.016). Quadrupedal and bipedal rats did not differ in the number of stands (P = 0.63) or in the amount of horizontal movement in the upright stance (P = 0.34) over 24 hours. Similar results were obtained when comparing hourly intervals. CONCLUSION: This study quantifiably indicates that bipedal rats do not assume a more erect posture and spend no more time in an upright position compared with quadrupedal rats. The upright posture may not be the cause of some previously reported anatomic changes observed in the bipedal rat.     

Genotype of the cystic fibrosis population of the Hunter Region of New South Wales

Objective : To determine the genotype of patients attending the cystic fibrosis clinic at John Hunter Hospital, Newcastle, Australia.
Methodology : Seventy-five of the 76 patients attending the clinic over a 6 month period had blood collected for genetic analysis of 17 of the cystic fibrosis (CF) gene mutations.
Results : Sixty-one per cent of the patients were homozygous for the ΔF508 mutation and all except one child had at least one ΔF508 mutation.
Discussion : Nearly 80% of the CF genes were the ΔF508 mutation. This prevalence suggests that the obligatory false negative rate of a newborn screening programme for CF based on a combination of immunoreactive trypsin and the ΔF508 gene may be as low as 4-5%.     

A 5-year review of a lympbhoedema service

Data for 714 patients referred during a 5-year period to a specialist lymphoedema service in Oxford, UK, have been recorded on a database. The annual number of new patients almost doubled from 103 to 195. In addition to initial assessments, there were over 1000 follow-up appointments per year. Most patients were seen as out-patients. Fifty-six per cent of the referrals were from Oxfordshire and the rest from further afield. The two largest groups referring patients to the service were general practitioners (43%) and the radiotherapy department (26%). Most referrals were female (84%), and the main cause of lymphoedema was cancer and cancer treatments (68%). After 2 years, only 15% of patients were still attending the clinic regularly. The number of patients receiving intensive treatment increased by almost 40%. These findings emphasize the need to target resources and expertise selectively in order to provide an optimal sericice to patients needing specialist help.     

Intestinal haemorrhage in Turner's syndrome

A 13-year-old girl with Turner's syndrome and bleeding from intestinal venous ectasia is reported. The various types of vascular anomaly of the bowel associated with Turner's syndrome are discussed. Awareness of these anomalies may help prevent unnecessary laparotomy in children with this syndrome.     

Hormonal changes in thalassaemia major

Patients with severe thalassaemia major suffer endocrine and other abnormalities before their eventual death from iron overload due to repeated blood transfusions. The endocrine status of 31 thalassaemic patients aged 2-5 to 23 years was investigated. Exact data were available on the rate and duration of blood transfusion in all of them and in many the liver iron concentration was also known. Although the patients were euthyroid, the mean serum thyroxine level was significantly lower, and the mean thyrotrophic hormone level significantly higher, compared with the values found in normal children. Forty oral glucose tolerance tests with simultaneous insulin levels were performed in 19 children, of whom 5 developed symptomatic diabetes and one had impaired tolerance. Previous tests on all 6 patients were available and some showed raised insulin levels possibly due to insulin resistance. 2 patients had clinical hypoparathyroidism and are described. The parathyroid hormone levels determined by radioimmunoassay in 25 patients were below the mean for the age group in all and outside the reference range in 16. Nonfasting plasma calcium levels were not reduced. Puberty was delayed in some patients. Concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) measured in urine from 7 girls and 5 boys showed considerable variation. In the boys there was an overall tendency for FSH and LH excretion to be low with regard to age, but with respect to puberty rating FSH exretions were normal or low and LH normal or raised. The girls showed a tendency for LH but not FSH excretion to be raised in relation to puberty rating. The severity of the endocrine changes was related to the degree of iron loading and is discussed in relation to previous work in which the iron loading has rarely been accurately indicated nor parathyroid status assessed.     

Comparison of tissue harmonic imaging with contrast (sonicated albumin echocardiography and Doppler myocardial imaging for enhancing endocardial border resolution

Endocardial resolution during 2-dimensional echocardiography is technically limited in at least 10% to 15% of patients. Recently, several ultrasound imaging innovations have been introduced that may improve endocardial resolution and decrease the proportion of technically difficult studies. This study compares tissue harmonic imaging, intravenous sonicated albumin, and Doppler myocardial imaging in patients with technically difficult echocardiograms. Twenty-eight patients with known or suspected cardiac disease and poor baseline endocardial resolution were studied. Only harmonic imaging (conventional and optimized for tissue) was superior to baseline fundamental imaging (p <0.001). Harmonic imaging was superior to baseline imaging in all myocardial regions and in the majority of patients, including those with the worst baseline studies.