Effects of galacto-oligosaccharides and a Bifidobacteria lactis-based probiotic strain on the growth performance and fecal microflora of broiler chickens.

A galacto-oligosaccharide (GOS) prebiotic was prepared by reacting a high concentration of lactose (40% wt/vol) with a beta-galactosidase enzyme for 24 h at 37 degrees C. The enzyme was produced from recombinant Pichia pastoris X-33 cells. The study aimed at evaluating the effects of the prebiotic, a Bifidobacterium lactis-based probiotic, and the combination of these dietary additives on BW, feed intake, feed conversion ratio, and fecal counts of total anaerobic bacteria, lactobacilli, and bifidobacteria in broiler chickens. No significant differences in BW, feed intake and feed conversion ratio were found among the various groups. The study showed that GOS selectively stimulated the fecal microflora of broiler chickens. Total anaerobic bacteria and lactobacilli were increased by 3.4- and 3.56-fold, respectively, in chickens fed the diet containing GOS (3 kg per 25 kg) and B. lactis for 40 d compared with those fed the control diet. The bifidobacteria population in chickens fed the diet containing GOS (3 kg per 25 kg) and B. lactis significantly increased 21-fold in comparison to the control-fed birds. In particular, increasing the dietary concentration of GOS was accompanied by significant increases (P < 0.05) in bifidobacteria counts. The detectable population of bifidobacteria was also greater (P < 0.05) in chickens fed the diet containing GOS and bifidobacteria when compared with chickens fed a bifidobacteria-containing ration only. These results suggest that using GOS in combination with a B. lactis-based probiotic favored intestinal growth of bifidobacteria in broiler chickens.

Intramuscular meptazinol and morphine in postoperative pain.

Meptazinol is an agonist-antagonist opioid analgesic believed to be unique in its selectivity for mu1 (high affinity) receptors and its cholinergic activity. Our objectives were to determine the relative analgesic potency of intramuscular meptazinol and morphine and to compare mood and side effects in 102 patients with cancer who have postoperative pain. Meptazinol (50, 100, and 200 mg) and morphine (4, 8, and 16 mg) were given for moderate to severe pain in a double-blind, randomized but balanced, incomplete block design. Serial multiple assessments of pain, relief, mood, and side effects were made. The most precise estimates of relative analgesic potency indicate that meptazinol is equivalent to 10 mg morphine at 120 mg (95% confidence interval 80 to 170 mg) for peak effect and at 175 mg (95% confidence interval 125 to 270 mg) for total effect. Mean (+/- SE) times to peak effect and to remedication were 0.9 +/- 0.1 and 3.6 +/- 0.2 hours for meptazinol and 1.4 +/- 0.1 and 4.8 +/- 0.4 hours for morphine at equianalgesic peak effects. The percentages of subjects with one or more side effects were 18, 49, and 73 for graded meptazinol doses and 32, 49, and 65 for graded morphine doses. Mean numbers of side effects per subject were 0.3, 1.5, and 3.5 for meptazinol and 0.5, 0.7, and 1.7 for morphine. Profiles of side effects differed. Mood improvement and overall satisfaction were dose related and greater for morphine than for meptazinol. Side effects may limit the use of meptazinol in doses that relieve severe postoperative pain.

Pharmacokinetics and pharmacodynamics of methadone in patients with chronic pain.

Concentrations of methadone in plasma, estimates of pain relief, and pupillary size were determined after a single intravenous dose (10 to 30 mg) of methadone hydrochloride to eight patients with chronic pain, five of whom had cancer. The pharmacokinetic parameter estimates reveal rapid and extensive distribution (Varea) and a slow apparent elimination half-life (t1/2) (mean Varea = 3.59 L/kg and harmonic mean t1/2 = 23 hours). The harmonic mean blood clearance is 106 ml/min, the harmonic mean renal clearance is 3.9 ml/min, the mean hepatic extraction ratio is 0.089, and plasma protein binding is 86% to 89%. These results suggest that only the free (unbound) fraction of methadone present in blood is extracted by the liver and that methadone can be classified as a low (hepatic)-extraction drug. The data were fit to a pharmacokinetic-pharmacodynamic model to obtain estimates of the steady-state plasma methadone concentration required to produce 50% of the maximum pain relief. This value varied from 0.04 to 1.13 micrograms/ml (mean = 0.29 micrograms/ml). These results indicate substantial interindividual variation in the relationship between changes in plasma methadone concentration and analgesia in patients with chronic pain receiving opioids. A pharmacokinetic-pharmacodynamic model may be useful for the individualization of analgesic dosage and therefore the optimization of pain management in patients with chronic pain.

Sublingual absorption of selected opioid analgesics.

Ongoing interest in the improvement of pain management with opioid analgesics had led to the investigation of sublingual opioid absorption. The present report determined the percent absorption of selected opioid analgesics from the oral cavity of normal subjects under conditions of controlled pH and swallowing when a 1.0 ml aliquot of the test drug was placed under the tongue for a 10-minute period. Compared with morphine sulfate at pH 6.5 (18% absorption), buprenorphine (55%), fentanyl (51%), and methadone (34%) were absorbed to a significantly greater extent (p less than 0.05), whereas levorphanol, hydromorphone, oxycodone, heroin, and the opioid antagonist naloxone were not. Overall, lipophilic drugs were better absorbed than were hydrophilic drugs. Plasma morphine concentration-time profiles indicate that the apparent sublingual bioavailability of morphine is only 9.0% +/- 11.9% (SD) of that after intramuscular administration. In the same subjects the estimated sublingual absorption was 22.4% +/- 9.2% (SD), indicating that the sublingual absorption method may overestimate apparent bioavailability. When the oral cavity was buffered to pH 8.5, methadone absorption was increased to 75%. Thus, an alkaline pH microenvironment that favors the unionized fraction of opioids increased sublingual drug absorption. Although absorption was found to be independent of drug concentration, it was contact time dependent for methadone and fentanyl but not for buprenorphine. These results indicate that although the sublingual absorption and apparent sublingual bioavailability of morphine are poor, the sublingual absorption of methadone, fentanyl, and buprenorphine under controlled conditions is relatively high.

Treatment of opioid-induced constipation with oral naloxone: a pilot study.

Opioids cause constipation by binding to specific opioid receptors in the enteric and central nervous systems. First-pass glucuronidation limits systemic bioavailability of oral naloxone. This study was designed to determine if oral naloxone could reverse opioid-induced constipation without precipitating abstinence or recrudescence of pain in opioid-dependent individuals. Concentrations of unmetabolized and total naloxone, including naloxone glucuronide, were measured by radioimmunoassay. A dose-related increase in symptoms of laxation resulted in all three opioid-dependent patients studied that paralleled the increase in active and total naloxone plasma levels. Withdrawal symptoms occurred with plasma naloxone area under the plasma concentration-time curves above 550 ng.min/ml and with dosing intervals less than 3 hours. Peak plasma levels did not predict withdrawal. Oral naloxone ameliorates opioid-induced constipation in opioid-dependent persons. Titration of dose to a maximum of 12 mg at least 6 hours apart may be needed to avoid adverse reactions.

Opioid responsiveness of cancer pain syndromes caused by neuropathic or nociceptive mechanisms: a combined analysis of controlled, single-dose studies.

We performed a combined analysis of the results from four controlled single-dose relative-potency studies to assess the impact of inferred pain mechanism on the response to an opioid drug. A total of 168 patients received 474 administrations of either morphine or heroin, and we assessed the analgesic response during a 6-hour period with visual analog scales. We summarized this as a total pain relief (TOTPAR) score. Two experienced pain clinicians reviewed information about pain characteristics and designated each case according to the inferred pain mechanism (neuropathic, nociceptive, or mixed) and the degree of confidence in the inferred mechanism (definite versus probable/possible). They grouped the cases as follows: nociceptive pain only (n = 205), neuropathic pain only (n = 49), and mixed (n = 220). We compared pain relief achieved by patients with different mechanisms, with TOTPAR adjusted for significant covariates (duration of prior opioid administration, doses of opioid administered in the previous 48 hours, pain intensity at the start of the study, BUN:creatinine ratio, and dose of administered opioid). The adjusted mean TOTPAR score of the group with any neuropathic pain was significantly lower than that of the group with nociceptive pain only (26.1 versus 20.4, p = 0.02). The score of the group with definite nociceptive pain alone (adjusted mean TOTPAR = 28.0) was significantly higher than scores of the groups with possible/probable nociceptive pain (TOTPAR = 19.9), mixed mechanisms (TOTPAR = 20.2), definite neuropathic pain alone (TOTPAR = 20.6), and possible/probable neuropathic pain alone (TOTPAR = 22.9).(ABSTRACT TRUNCATED AT 250 WORDS)

Sources of variation in analgesic responses in cancer patients with chronic pain receiving morphine.

Our objective was to identify and quantify sources of variation in the relief of chronic pain with morphine. Relief scores were extracted from records obtained during controlled trials of analgesics in cancer patients with chronic pain in which intramuscular morphine was the assay standard. Relief data from 715 patients after 565 8-mg and 538 16-mg doses were segregated according to age, race, sex, pre-drug pain intensity, character and site. Middle-aged patients obtained relief after 8 mg comparable to relief obtained by younger patients after 16 mg; oldest patients obtained relief after 8 mg comparable to relief obtained by middle-aged patients after 16 mg. Blacks receiving 8 mg obtained relief comparable to whites receiving 16 mg. Sex-related differences were not significant. Patients with moderate, as compared to severe, pre-drug pain obtained significantly greater relief only after 16 mg. Patients reporting dull pain obtained relief after 8 mg comparable to relief obtained with sharp pain after 16 mg. Patients with abdominal pain obtained relief after 8 mg comparable to relief of pain in the chest or arms after 16 mg. These results provide dose-related evidence of variation in relief with morphine in chronic cancer pain and establish particular patient and pain characteristics as variables for which controls should be provided in analgesic assays.

Comparisons of the analgesic effects of oral and intramuscular oxymorphone and of intramuscular oxymorphone and morphine in patients with cancer.

The relative analgesic potency of oral and intramuscular oxymorphone was evaluated in a double-blind crossover comparison of graded single doses in patients with chronic pain due to cancer. When both duration and intensity of analgesia are considered (total effect), oral oxymorphone was 1/6 as potent as the intramuscular form. In terms of peak effect, however, oral oxymorphone was only 1/14 as potent. These values are almost identical to those obtained in a previous study comparing oral with intramuscular morphine. The analgesic effect of oral oxymorphone rose to a peak later and had a longer duration than the effect of intramuscular oxymorphone. Intramuscular oxymorphone and morphine were also compared in a similar patient group. Intramuscular oxymorphone proved to be 8.7 times as potent as morphine in terms of total analgesic effect and 13 times as potent in terms of peak effect. In roughly equinalgesic doses, the occurrence of side effects was qualitatively and quantitatively similar for oral and intramuscular oxymorphone and for intramuscular oxymorphone and morphine.

Plasma levels and analgesia following deltoid and gluteal injections of methadone and morphine.

The objective was to determine whether deltoid as compared to gluteal injection of morphine and methadone produce differential plasma levels and analgesic effects. Thirty-two postoperative cancer patients received deltoid and gluteal injections of morphine, 8 and 16 mg, within a double-blind, twin crossover design. Forty-four patients received deltoid or gluteal methadone, 10 mg. Deltoid morphine resulted in peak plasma levels 1.8 times (P less than 0.05) those observed following gluteal morphine. Deltoid methadone resulted in peak levels 2.5 times (P less than 0.005) those following gluteal injection. Deltoid morphine resulted in an area under the drug level-time (0 to 4 hours) curve 1.4 times (N.S.) the area observed following gluteal injection. Deltoid methadone resulted in an area under the drug level-time (0 to 4 hours) curve 2.2 times (P less 0.001) the area observed following gluteal injection. Deltoid methadone, but not morphine, provided greater (1.7-fold, P less than 0.05) pain relief than gluteal injection. If more rapid and enhanced analgesia is indicated, then the deltoid site may be preferable over the gluteal site for standard doses of methadone and other lipid soluble analgesics. In addition, the relative potency of compounds of widely differing lipid solubility may depend upon the site of intramuscular injection.

Relative analgesic potency of oral zomepirac and intramuscular morphine in cancer patients with postoperative pain.

A twin crossover assay of oral zomepirac and intramuscular morphine was completed in 159 cancer patients with postoperative pain. Zomepirac was a surprisingly effective oral analgesic in these patients, 100 mg orally being roughly equivalent to 16 mg intramuscular morphine. Time-effect data indicate that the peak effect for oral zomepirac may occur slightly later than that for morphine but that zomepirac is relatively rapidly effective after oral administration. Side effect occurrence was roughly in the same range for both drugs, with drowsiness, nausea, dry mouth, and feelings of weakness being observed after both drugs while sweating was observed more frequently after zomepirac. The assay further provided a demonstration of the effectiveness of the twin crossover design as a clinical assay method, providing increased sensitivity of crossover data in a patient population available for only a limited number of study treatments.

Crossover trials in clinical analgesic assays: studies of buprenorphine and morphine.

Analgesic studies of buprenorphine, a thebaine derivative and potent partial narcotic agonist, were carried out in patients with cancer who had postoperative or chronic pain. Intramuscular buprenorphine was compared with intramuscular morphine in a series of sequentially related, twin crossover assays and was found to be about 25 times as potent as morphine. Side effects were essentially morphine-like. In a second assay, the acceptability and analgesic activity of sublingual buprenorphine was studied in a 6-dose, balanced, incomplete block assay, a modification of the twin crossover design employed in the all-intramuscular trial. Sublingual buprenorphine was found to be about 15 times as potent as intramuscular morphine and was well accepted by our patients. The 4-dose twin crossover trial in which doses are adjusted sequentially is more flexible in that a wide range of doses may be studied, but it lacks the ability of the 6-dose design to provide estimates of the curvature of the dose-response slopes of the study drugs. When first-dose-only data were analyzed as parallel group assays, the main difference in results compared with the crossover studies was a decrease in efficiency and sensitivity.

Cancer pain management with a controlled-release oral morphine preparation.

An open-label pilot study was conducted to assess the efficacy and acceptability of a controlled-release oral morphine formulation, MS Contin tablets, when administered "by the clock" two to three times daily as a substitute for opioids given on request to patients with pain caused by advanced cancer. Initially, four-hourly does of standard "immediate-release" oral morphine sulfate tablets were substituted for the patients' prior analgesic medication and titrated to individual needs. Forty of the 47 patients enrolled in the study were subsequently switched to an eight-hourly MS Contin regimen (three patients became too ill to continue the study, and four left the study during the immediate-release titration phase because of adverse reactions that may have been drug related). Small "rescue" doses of standard oral morphine were available to the patients, but they were taken infrequently. Twenty-one of the 37 patients maintained on the eight-hourly schedule consented to be treated with, and were subsequently stabilized on, MS Contin administered every 12 hr, with a reduction of over 20% in their average daily morphine dose. Most of the patients rated the controlled-release medication superior to the standard oral morphine tablets in terms of both convenience and adequacy of relief.

Benzydamine HCl, a new agent for the treatment of radiation mucositis of the oropharynx.

Benzydamine HCl is a new nonsteroidal analgesic and anti-inflammatory compound which is not chemically related to local anesthetics such as procaine and xylocaine. A double-blind, randomized clinical investigation was carried out to determine the analgesic and anti-inflammatory effectiveness of benzydamine HCl in patients with radiation-induced mucositis of the oropharynx. Of the 67 patients in the study, 37 were on benzydamine and 30 on placebo. Patients developed radiation mucositis, hyperemia, and throat pain when the total radiation dose reached above 2,000 rad over 2 weeks (200 rad per fraction, five treatments per week). Analysis of the data showed that benzydamine HCl used as a rinse/gargle provided a statistically significant and clinically meaningful alleviation of the symptoms of oropharyngeal mucositis. There was also significant improvement in terms of reduction in hyperemia and mucositis in benzydamine group. No systemic side effects associated with benzydamine medication were noted. In view of the relative ineffectiveness of systemic analgesics and topical anesthetics for these conditions, benzydamine HCl promises to be a useful addition to the therapeutic armamentarium.

Guidelines for use of controlled-release oral morphine in cancer pain management. Correlation with clinical experience.

An open study of 47 patients with cancer pain treated with repeated doses of a controlled-release oral morphine tablet was conducted to assess the acceptability of this drug and develop guidelines for its use. Each patient kept a detailed record of pain, analgesic intake, side effects, and other medications. A nurse observer/clinician followed these patients on a daily basis and kept similar records. Of 47 patients who began the study, 37 were successfully stabilized with standard morphine sulfate tablets and then switched to controlled-release morphine (CRM). Twenty-one patients who completed the study took CRM every 12 h, and 16 patients received a dose every 8 h. Doses of the CRM ranged from 30 mg every 12 h to 360 mg every 8 h. Less frequent doses and uninterrupted sleep were reported advantages. All of the patients completing the study chose to continue this method of pain management and extended care data were obtained from each patient poststudy through continued monitoring.

A clinical study of benzydamine for the treatment of radiotherapy-induced mucositis of the oropharynx.

A double-blind, randomized clinical study was undertaken to determine the analgesic and antiinflammatory effectiveness of benzydamine in patients with radiation-induced mucositis of the oropharynx. Of the 67 patients in the study, 37 patients were on benzydamine and 30 patients on a placebo. The results of the study showed that benzydamine possessed a significant analgesic activity as evidenced by relief of mouth and throat pain induced by radiation therapy. It is also noted that the patients on benzydamine exhibited a cumulative relief of oral pharyngeal pain and discomfort over the time of treatment, as compared to those on the placebo. These effects of benzydamine in the present study might be a result of the antiinflammatory property of the drug. The cumulative and prolonged effectiveness of benzydamine makes it of distinct value compared with the commonly available local anaesthetics such as lidocaine. Benzydamine appears to provide a useful addition to the therapeutic armamentarium for alleviating the symptoms of oral pharyngeal mucositis.

Effects of Lactobacilli and an acidophilic fungus on the production performance and immune responses in broiler chickens.

Accumulated lines of evidence indicate that inactivated probiotics could have beneficial effects similar to those of live probiotics. Two strains of disrupted, cobalt-enriched, lactic acid bacteria (Lactobacillus acidophilus and Lactobacillus casei) and a disrupted fungal mycelium (Scytalidium acidophilum) were spray-mixed onto a mash basal feed, in 2 concentrations, prior to pelleting. The effects of these probiotics on production performance and immune response in broiler chickens were investigated. The production parameters, including BW, feed intake (FI), BW gain (BWG), and feed conversion ratio (FCR), were monitored weekly during a 6-wk trial. The immune response was evaluated by immunizing the birds with the antigen keyhole limpet hemocyanin (KLH) followed by a serological assay to measure blood IgA and IgG titers. Some of the production parameters were significantly improved by low L. casei (LCL; for BW and BWG), high L. acidophilus (LAH; for BW and BWG), and high fungal (FH; for BW, BWG, and FI) in comparison with the nonadditive control (NC-). However, these 3 treatments (LCL, LAH, and FH) did not enhance the measured immune responses. Instead, the titers of serum KLH-specific IgA in high L. casei (LCH) and low L. acidophilus (LAL) were significantly higher than those of NC-, 10 d after immunization. None of the probiotic treatments increased the titer of KLH-specific IgG in blood. Our results indicate that disrupted and cobalt-enriched L. acidophilus or L. casei was able to enhance production performance of broiler chickens. The fungal mycelium, S. acidophilum, when used at a high concentration, also demonstrated its potential for the first time to be used as a probiotic. In addition, the optimal concentration for administering probiotics is strain dependent. A higher dose does not always result in a better performance.