Edda C. Villaamil

Potential utility of the peripheral analgesic properties of morphine in stomatitis-related pain: a pilot study.

To determine the potential clinical utility of peripheral opioid action using a clinical model of cancer treatment‐induced inflammation and pain that allowed for topical application of morphine in the damaged tissue (oral mucosa). This pilot study followed a two blocks design. Ten patients with painful oral mucositis were enrolled in the first block (dose–response relationship finding) and randomized in two groups to receive oral rinses with 15 ml of either 1‰ or 2‰ morphine solution. Twenty‐two patients were enrolled into the second block (efficacy and safety determination). Additionally, serum concentrations of morphine were measured in five representative patients. In the first block (n=10) a dose–response relationship for topical morphine was found. Rinses with 2‰‐morphine solution showed better pain relief (median 80%, range 70–80%) than those with 1‰ (median 60%, range 55–70%; P=0.0238). Therefore, subsequent patients enrolled for the second block (n=22) received oral rinses with 2‰‐morphine solution. In these patients the time to good (≥50%) or to complete (100%) pain relief was 28 (±12) min after the first mouthwash, and the duration of relief was on average 216 (±25) min. Twenty patients (90%) received the successive mouthwashes every 3 h and 10% of them every 2 h. The duration of severe pain at the moment of swallowing was 5.17 (±1.47) days. Only six patients needed supplementary analgesia, and the time elapsed before the first supplemental analgesic was 1.18 (±0.8) days. The duration of severe functional impairment was 1.52 (±1.31) days, thus allowing us to feed the patient by mouth with liquid‐food supplementation. During our experiment no systemically active detectable concentrations of morphine were found (GC–MS analysis). The most important side effect attributable to morphine mouthwashes was burning/itching sensation (very mild to mild intensity). Patients with painful chemoradiotherapy‐induced stomatitis could be alleviated using topical morphine mouthwashes.

Heavy metals in sediments and soft tissues of the Antarctic clam Laternula elliptica: more evidence as a possible biomonitor of coastal marine pollution at high latitudes?

Studies on metal contamination in 25 de Mayo Island, Antarctica, yielded controversial results. In this work, we analyzed Antarctic marine sediments and Antarctic clam (Laternula elliptica) tissues to investigate the possible use of this mollusk as a biomonitor of metals and to identify the sources of metal pollution. Different types of paint from several buildings from Carlini Station were examined to assess their contribution to the local and random metal pollution. Five sediment samples, 105 L. elliptica specimens (40.2-78.0mm length) and four types of paint were analyzed to quantify Cd, Cr, Cu, Fe, Mn, Pb and Zn using inductively coupled plasma-optical emission spectrometry. Metal concentrations in sediments were lower than the global averages of the earths crust, with the exception of Cd and Cu. These results were related to the contribution of the local fresh-water runoff. The different varieties of paint showed low levels of Cu, Mn, Fe and Zn, whereas a broad range of values were found in the case of Cr and Pb (20-15,100 μg·g(-1) and 153-115,500 μg·g(-1) respectively). The remains of the paint would be responsible for the significant increases in Cr and Pb which are randomly detected by us and by other authors. High levels of Fe and Cd, in comparison to other Antarctic areas, appear to be related to the terrigenous materials transported by the local streams. Accumulation indexes suggested that kidney tissue from L. elliptica could be an adequate material for biomonitoring pollution with Cd, Zn and probably also Pb. In general, relationships between size and metal contents reported by other authors were not verified, suggesting that this issue should be revised.

First analytical chemistry study on drug abuse in the Buenos Aires (Argentina) University students

One hundred samples were randomly selected from urine specimens collected from Buenos Aires University students, 50 males and 50 females, whose ages ranged from 19 to 47 years. Cocaine (COC), cannabinoids (CNNs), amphetamines (AMs), benzodiazepines (BZDs), barbiturates (BBTs), opiates (OPs) and salicylates (SAs) were searched for by ELISA, FPIA, normalized TLC, HPLC and GC/MS techniques. The presence of COC was detected in five samples, CNN in two and SA in twelve. No evidence of AMs, BZDs, BBTs or OPs was found.

Variations in rat biochemical parameters after buckshot implant

Twenty eight albino Wistar rats were implanted with two 100 mg lead spheres: 14 received the implant in the peritoneum (P) and 14 in the thigh (T). Variations in the activity of delta-aminolevulinic dehydratase (ALAD), of urinary delta-aminolevulinic acid (ALAU), of hematoporphyrins (HP) and of lead blood levels (BPb) were then determined at 30, 60 and 90 days with respect to basal values. Parallel determinations were performed by the same schedule in 7 rats implanted with two glass beads and in 8 sham animals receiving surgical incision alone. Techniques employed for ALAD were Berlin and Schaller; for ALAU, Tomokuni and Ogata; for HP, Piomelli; and for BPb, atomic absorption spectrophotometry. As indicators of lead presence, HP and ALAU proved better, both in P and in T rats. The replacement of lead buckshot for small game hunting by other less toxic elements is recommended.