High prevalence of vitamin D deficiency in elderly patients with advanced osteoarthritis scheduled for total knee replacement associated with poorer preoperative functional state

Vitamin D deficiency has been reported previously in patients with osteoarthritis undergoing total hip arthroplasty. We found a high prevalence of vitamin D deficiency in elderly patients with advanced knee osteoarthritis scheduled for total knee replacement and also a significant association with a lower preoperative functional state. A review of the literature is given on vitamin D deficiency in patients with knee osteoarthritis and the association with lower outcome scores after arthroplasty is discussed.     

Can the Ottawa and Pittsburgh rules reduce requests for radiography in patients referred to acute knee clinics?

Our aim was to study the role of the Ottawa and Pittsburgh rules to reduce the unnecessary use of radiographs following knee injury. We prospectively reviewed 106 patients who were referred to our clinic over a 3-month period. The Ottawa and Pittsburgh rules were applied to individual patients to evaluate the need for radiography. One hundred and one patients (95%) had radiography of their knee. Five patients (5%) had a fracture of their knee and in all cases, the Ottawa and Pittsburgh knee rules were fulfilled. Using the Ottawa rules, 27 radiographs (25%) could have been avoided without missing a fracture. Using the Pittsburgh rules, 32 radiographs (30%) could have been avoided. The Ottawa and Pittsburgh rules have a high sensitivity for the detection of knee fractures. Their use can aid efficient clinical evaluation without adverse clinical outcome and may reduce healthcare costs.     

Bifid origin of the left vertebral artery

Two patients demonstrating a bifid origin of the left vertebral artery are described. The embryologic origin of this anomaly is reviewed together with diagnostic and therapeutic implications, emphasizing the importance of knowledge and recognition of the anomaly. It is suggested that this anomaly is not as rare as previously thought.     

5-HT1A receptors are involved in the cannabidiol-induced attenuation of behavioural and cardiovascular responses to acute restraint stress in rats

Background and purpose

Cannabidiol (CBD) is a non-psychotomimetic compound from Cannabis sativa which induces anxiolytic- and antipsychotic-like effects in rodents. These effects could be mediated by facilitation of the endocannabinoid system or by the activation of 5-HT_1A receptors. As either of these mechanisms could promote adaptation to inescapable stress, the aim of the present work was to test the hypothesis that CBD would attenuate the autonomic and behavioural consequences of restraint stress (RS). We also investigated if the responses to CBD depended on activation of 5-HT_1A receptors.

Experimental approach

Male Wistar rats received i.p. injections of vehicle or CBD (1, 10 or 20 mg kg⁻¹) and 30 min later were submitted to 60 min of restraint where their cardiovascular responses were recorded. The protocol of the second experiment was similar to the first one except that animals received i.p. injections of the 5-HT_1A receptor antagonist WAY100635 (0.1 mg kg⁻¹) before CBD treatment and exposure to restraint. 24 h later they were also tested in the elevated plus-maze (EPM), an animal model of anxiety.

Key results

Exposure to RS increased blood pressure and heart rate and induced an anxiogenic response in the EPM 24 h later. These effects were attenuated by CBD. WAY100635 by itself did not change the cardiovascular and anxiogenic response to RS, but blocked the effects of CBD.

Conclusion and implications

The results suggest that CBD can attenuate acute autonomic responses to stress and its delayed emotional consequences by facilitating 5-HT_1A receptor-mediated neurotransmission.     

Cloning and pharmacological characterization of the dog P2X7 receptor

Background and purpose:

Human and rodent P2X7 receptors exhibit differences in their sensitivity to antagonists. In this study we have cloned and characterized the dog P2X7 receptor to determine if its antagonist sensitivity more closely resembles the human or rodent orthologues.

Experimental approach:

A cDNA encoding the dog P2X7 receptor was isolated from a dog heart cDNA library, expressed in U-2 OS cells using the BacMam viral expression system and characterized in electrophysiological, ethidium accumulation and radioligand binding studies. Native P2X7 receptors were examined by measuring ATP-stimulated interleukin-1β release in dog and human whole blood.

Key results:

The dog P2X7 receptor was 595 amino acids long and exhibited high homology (>70%) to the human and rodent orthologues although it contained an additional threonine at position 284 and an amino acid deletion at position 538. ATP possessed low millimolar potency at dog P2X7 receptors. 2′-&3′-O-(4benzoylbenzoyl) ATP had slightly higher potency but was a partial agonist. Dog P2X7 receptors possessed relatively high affinity for a number of selective antagonists of the human P2X7 receptor although there were some differences in potency between the species. Compound affinities in human and dog blood exhibited a similar rank order of potency as observed in studies on the recombinant receptor although absolute potency was considerably lower.

Conclusions and implications:

Dog recombinant and native P2X7 receptors display a number of pharmacological similarities to the human P2X7 receptor. Thus, dog may be a suitable species for assessing target-related toxicity of antagonists intended for evaluation in the clinic.     

Nonbronchial systemic collateral arteries: significance in percutaneous embolotherapy for hemoptysis

Twenty patients with massive or recurrent hemoptysis underwent percutaneous transcatheter embolotherapy between 1979 and 1986 for the following diseases: cavitary aspergillosis (n = 4); cystic fibrosis (n = 4); tuberculosis (n = 3); bronchogenic carcinoma (n = 3); bronchiectasis (n = 3); small cell lung carcinoma 6 years after irradiation (n = 1); congenital heart disease, after Glenn and Blalock anastomoses (n = 1); and unknown interstitial disease (n = 1). Bronchial arteries were embolized in all but one patient. In nine patients (45%) nonbronchial systemic collateral arteries contributed significantly to areas of pathologic pulmonary tissue and frequently were the major arterial supply. These nonbronchial systemic collaterals included branches of the subclavian and axillary arteries (n = 7), intercostal arteries (n = 5), and phrenic arteries (n = 3) and accounted for 59.5% of the total number of arteries embolized. Recognition and occlusion of nonbronchial systemic collaterals providing blood to hypervascular pulmonary lesions is essential for successful percutaneous embolotherapy of hemoptysis.