Case-control association analysis of polymorphisms in the δ-opioid receptor, OPRD1, with cocaine and opioid addicted populations

BACKGROUND

Addiction susceptibility and treatment responsiveness are greatly influenced by genetic factors. Sequence variation in genes involved in the mechanisms of drug action have the potential to influence addiction risk and treatment outcome. The opioid receptor system is involved in mediating the rewarding effects of cocaine and opioids. The μ-opioid receptor (MOR) has traditionally been considered the primary target for opioid addiction. The MOR, however, interacts with and is regulated by many known MOR interacting proteins (MORIPs), including the δ-opioid receptor (DOR).

METHODS

The present study evaluated the contribution of OPRD1, the gene encoding the DOR, to the risk of addiction to opioids and cocaine. The association of OPRD1 polymorphisms with both opioid addiction (OA) and cocaine addiction (CA) was analyzed in African American (OA n=336, CA n=503) and European American (OA n=1007, CA n=336) populations.

RESULTS

The primary finding of this study is an association of rs678849 with cocaine addiction in African Americans (allelic p=0.0086). For replication purposes, this SNP was analyzed in a larger independent population of cocaine addicted African Americans and controls and the association was confirmed (allelic p=4.53 × 10(-5); n=993). By performing a meta-analysis on the expanded populations, the statistical evidence for an association was substantially increased (allelic p=8.5 × 10(-7)) (p-values non-FDR corrected).

CONCLUSION

The present study suggests that polymorphisms in OPRD1 are relevant for cocaine addiction in the African American population and provides additional support for a broad role for OPRD1 variants in drug dependence.

A multi-centre study of tiaprofenic acid ('Surgam') and five comparative drugs in rheumatoid arthritis and osteoarthritis in general practice

Two multi-centre studies were carried out in general practice comparing tiaprofenic acid ('Surgam') with five other non-steroidal anti-inflammatory agents (ibuprofen, indomethacin, naproxen, piroxicam and benoxaprofen), one in rheumatoid arthritis and one in osteoarthritis. Two hundred and seventy-seven general practitioners provided completed case records for 856 patients, 373 with rheumatoid arthritis and 483 with osteoarthritis. Approximately half of the patients received tiaprofenic acid and the remainder one of the other drugs. Results showed that tiaprofenic acid was at least as effective as the other drugs. The incidence of side-effects was similar for each group except in the osteoarthritis trial where there was a higher incidence in the patients receiving indomethacin. The overall withdrawal rate from each trial was 4.6% and 5.2% in rheumatoid arthritis and osteoarthritis, respectively.

A controlled trial of different treatment regimens in patients with urinary tract infections after lower urinary tract surgery

One hundred and four patients who developed urinary tract infections after catheterization for acute retention of urine and surgery of the bladder or urethra were randomly allocated to four treatment groups. Analysis of the results in 65 patients showed that co-trimoxazole and 1 g cephradine administered twice daily for 1 week were successful in eradicating the urinary tract infections in 93% and 88% of the patients, respectively. The same dose of cephradine administered 4-times a day eradicated 64% of the infections. In patients for whom no treatment was given, the original infection did not clear in 65%. Escherichia coli and coagulase-negative staphylococci were the commonest infecting organisms. The in vitro sensitivity testing of antibiotics did not correlate well with the successful eradication of the infecting organism.

The effects on normal skin of adhesives from stoma appliances

The irritancy of 7 adhesive plasters from different ostomy appliances was compared in 30 normal subjects. The adhesives were replaced both daily and weekly over a 21-day period. Using a clinical rating scale, the results slowed that "Stomahesive" had a significantly less irritating effect on the skin than the other plasters, both when removed daily and when removed weekly. The difference between daily and weekly removal reached statistical significance at the end of Weeks 2 and 3, and the results suggest that the nature of the adhesive is more important than the frequency of removal.

Cephradine in the treatment of chronic recurrent infections of the urinary tract

Twenty-two patients with chronic recurrent bacterial urinary tract infection, most of whom had underlying physical abnormalities of the tract, were treated with 500 mg cephradine 4-times daily for 10 to 15 days. Eight patients remained completely clear of infection after 2 to 3 months of treatment. This was regarded as a satisfactory result in view of the difficulty in treating this type of case and considering previous unsuccessful courses of antibacterial therapy.

Cephradine in urinary tract infections: a double-blind comparison with ampicillin

A double-blind trial was carried out comparing cephradine and ampicillin in the treatment of urinary tract infections in 42 females attending a hospital Department of Obstetrics and Gynaecology. Results showed that patients did better in the cephradine group than the ampicillin group, both bacteriologically and clinically. The numbers in each group were small, however, and did not reach statistical significance.