Bombesin improves survival from methotrexate-induced enterocolitis.

OBJECTIVE: The authors determined whether bombesin could improve survival from methotrexate (MTX)-induced enterocolitis. SUMMARY BACKGROUND DATA: Bombesin prevents gut mucosal atrophy, which is produced by feeding rats an elemental diet. Administration of MTX produces a lethal enterocolitis in rats fed an elemental diet. METHODS: On treatment day 0, 60 rats were divided randomly into three groups and fed an elemental diet (Vivonex TEN, Sandoz, Minneapolis, MN) as the only source of nutrition. Groups were subdivided further to receive either saline or bombesin (10 micrograms/kg, subcutaneously, three times a day) beginning either on day 0 or day 14. Methotrexate (20 mg/kg, intraperitoneally) was given to all rats 14 days after the start of an elemental diet. RESULTS: Bombesin prevented the mucosal atrophy in the ileum produced by the elemental diet and significantly decreased mortality in rats given MTX (whether given as a pretreatment or at the time of MTX administration). CONCLUSION: Bombesin significantly improved survival in a lethal model of MTX-induced enterocolitis, possibly by maintaining gut mucosal structure. Administration of bombesin to patients receiving chemotherapy may be clinically useful in preventing the severe enterocolitis induced by various chemotherapeutic agents.     

Performance of Residents and Anesthesiologists in a Simulation-based Skill Assessment

Background: Anesthesiologists and anesthesia residents are expected to acquire and maintain skills to manage a wide range of acute intraoperative anesthetic events. The purpose of this study was to determine whether an inventory of simulated intraoperative scenarios provided a reliable and valid measure of anesthesia residents' and anesthesiologists' skill.

Methods: Twelve simulated acute intraoperative scenarios were designed to assess the performance of 64 residents and 35 anesthesiologists. The participants were divided into four groups based on their training and experience. There were 31 new CA-1, 12 advanced CA-1, and 22 CA-2/CA-3 residents as well as a group of 35 experienced anesthesiologists who participated in the assessment. Each participant managed a set of simulated events. The advanced CA-1 residents, CA-2/CA-3 residents, and 35 anesthesiologists managed 8 of 12 intraoperative simulation exercises. The 31 CA-1 residents each managed 3 intraoperative scenarios.

Results: The new CA-1 residents received lower scores on the simulated intraoperative events than the other groups of participants. The advanced CA-1 residents, CA-2/CA-3 residents, and anesthesiologists performed similarly on the overall assessment. There was a wide range of scores obtained by individuals in each group. A number of the exercises were difficult for the majority of participants to recognize and treat, but most events effectively discriminated among participants who achieved higher and lower overall scores.     

Issues in community care services

In the first part of this series on issues in ward management facing charge nurses, Helen Evers addresses the problem of communication between hospital and community on patient discharges. Recent years have seen the development of liaison and co-ordinator posts whose incumbents aim to facilitate planned and organised discharge procedures, but the appointment of such personnel may not provide a complete answer to the problem. The ultimate arbiter of effective transition from hospital to home is more likely to be the quality of communication between charge and district nurse.     

Mercury and Selenium Concentrations in Livers and Eggs of Common Loons (Gavia immer) from Minnesota

Mercury and selenium act as mutual antagonists in mature birds, but their toxicity is additive or synergistic in avian embryos and immature birds. Twenty eggs and livers from 18 mature and 9 immature common loon carcasses found in Minnesota were collected. Livers and eggs were analyzed for mercury and selenium by atomic emission and atomic absorption spectroscopy. Liver mercury concentrations were significantly higher in mature loons compared to those of immature loons and eggs. Liver selenium concentrations were significantly higher in mature loons than those of immature loons, and selenium concentrations in immature loon livers were significantly higher than levels in eggs. There was a significant positive correlation between mercury and selenium in loon livers. There was a negative correlation between mercury and selenium in eggs. Received: 2 February 2001/Accepted: 28 May 2001     

Treatment of cremaster synkinesias with botulinum toxin A: a video case report.

Synkinesias secondary to nerve lesions and aberrant re-innervation are well-known phenomena especially after lesions of the facial nerve. Synkinesias can successfully be treated with botulinum toxin A (BTx A). Synkinesias of the cremaster muscle have not been described or treated to date. We present the case of a 62-year-old man who developed synkinesias of both cremaster muscles after extensive laparatomy for esophageal cancer. Treatment of synkinesias with various oral medications had been unsuccessful. Electromyography-guided injections of BTx A in both cremaster muscles (15 MU on the right and 10 on the left) led to significant symptom relief for an average of 8 weeks. We present the case including pre- and posttreatment video clips.     

Ovum recovery after microsurgical reanastomosis of the rabbit oviduct

Causes for failure of pregnancy after tubal reconstructive surgery are incompletely understood. The impact of microsurgical resection reanastomosis on ovum recovery was studied in the rabbit oviduct. One hundred sixty rabbits were divided into three groups: one experimental group in which a resection reanastomosis was made in the ampullar or isthmic tubal segment, respectively, and two control groups. After mating, ovum recovery was evaluated. In ampullary operated oviducts the ovum recovery rate was significantly lower compared with recovery rates in isthmically operated and in control oviducts. Furthermore, in ampullary operated oviducts peritoneal transmigration of ova was frequently observed. Disturbances in ovum pickup from the ovarian surface or the peritoneal cavity seem to be responsible for the decrease in recovery rate found in the ampullary operated oviducts.     

Halothane inhibits two components of calcium current in clonal (GH3) pituitary cells.

The effect of halothane on isolated calcium (Ca2+) current of clonal (GH3) pituitary cells was investigated using standard whole-cell clamp techniques at room temperature. Halothane (0.1-5.0 mM) reversibly reduced both the low-threshold, transient [low-voltage-activated (LVA)] component and the high-threshold [high-voltage-activated (HVA)] component of Ca2+ current. Halothane had little effect on the voltage dependence of activation or inactivation of either component of Ca2+ current. Inhibition of the peak high-threshold Ca2+ current was half-maximal at about 0.8 mM halothane, with maximal inhibition (100%) occurring with 5 mM halothane. When measured at the end of a 190-msec command step, half-maximal reduction of high-threshold current occurred at less than 0.5 mM halothane. The low-threshold transient current was less sensitive to halothane, with half-maximal inhibition of peak transient current activated at -30 mV occurring at approximately 1.3 mM. The effect of halothane on the HVA current was apparently not mediated by changes in intracellular Ca2+ concentration. The ability of halothane to inhibit Ca2+ current was unaffected by either the inclusion of the rapid Ca2+ buffer 1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid (BAPTA) in the recording pipette or exposure of the cell to 10 mM caffeine. To assess the selectivity of the effect of halothane, the actions of halothane on two components of voltage-activated potassium (K+) current observed in the absence of extracellular Ca2+ and on voltage-dependent sodium (Na+) current were also examined. Halothane had no effect on the voltage-dependent, inactivating K+ current of GH3 cells at concentrations up to 1.2 mM. In contrast, the non-inactivating K+ current, though less sensitive to halothane than either Ca2+ current, was reduced by about 40% by 1.2 mM halothane at +20 mV. Peak Na+ current was also blocked by halothane, but 50% block required around 2.6 mM halothane with little effect at 1.6 mM. Reduction of Na+ current was associated with a substantial negative shift in the steady-state inactivation curve. Although the results indicate that a number of voltage-dependent ionic currents are sensitive to halothane, both components of Ca2+ current exhibit a greater sensitivity to halothane than any of three other voltage-dependent currents in GH3 cells. These results show that GH3 cell Ca2+ currents are selectively inhibited by clinically appropriate concentrations of halothane and that the reduction of Ca2+ current can account for the inhibition by halothane of TRH- or KCl-induced prolactin secretion in GH3 cells.