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S L Collins

Publications and source records attributed to S L Collins.

At least 19 recordsLinked to original sources
PubMed2006

Stream insect occupancy-frequency patterns and metapopulation structure.

An understanding of the distribution patterns of organisms and the underlying factors is a fundamental goal of ecology. One commonly applied approach to visualize these is the analysis of occupancy-frequency patterns. We used data sets describing stream insect distributions from different regions of North America to analyze occupancy-frequency patterns and assess the effects of spatial scale, sampling intensity, and taxonomic resolution on these patterns. Distributions were dominated by satellite taxa (those occurring in or=90% of sites) determined the overall modality of occupancy-frequency patterns. The proportions of satellite taxa increased with spatial scale and showed positive relationships with sampling intensity (r2=0.74-0.96). Furthermore, analyses of data sets from New York (USA) showed that generic-level assessments underestimated the satellite class and occasionally shifted occupancy-frequency distributions from unimodal to bimodal. Our results indicate that, regardless of species- or generic-level taxonomy, stream insect communities are characterized by satellite species and that the proportion of satellite species increases with spatial scale and sampling intensity. Thus, niche-based models of occupancy-frequency patterns better characterize stream insect communities than metapopulation models such as the core-satellite species hypothesis.

Animals↗
PubMed2004

Plant community responses to resource availability and heterogeneity during restoration.

Availability and heterogeneity of resources have a strong influence on plant community structure in undisturbed systems, as well as those recovering from disturbance. Less is known about the role of resource availability and heterogeneity in restored communities, although restoration provides a valuable opportunity to test our understanding of factors that influence plant community assembly. We altered soil nitrogen (N) availability and soil depth during a prairie restoration to determine if the availability and/or heterogeneity of soil resources influenced plant community composition in restored grassland communities. Plant community responses to three levels of N availability (ambient, enriched by fertilization, and reduced by carbon amendment) and two levels of soil depth (deep and shallow) were evaluated. In addition, we evaluated plant community responses to four whole plot heterogeneity treatments created from the six possible combinations of soil N availability and soil depth. The soil depth treatment had little influence on community structure during the first 3 years of restoration. Total diversity and richness declined over time under annual N enrichment, whereas diversity was maintained and richness increased over time in soil with reduced N availability. Non-native species establishment was lowest in reduced-N soil in the initial year, but their presence was negligible in all of the soil N treatments by the second year of restoration. Panicum virgatum, a native perennial C(4) grass, was the dominant species in all soil N treatments by year three, but the magnitude of its dominance was lowest in the reduced-N soil and highest in enriched-N soil. Consequently, the relative cover of P. virgatum was strongly correlated with community dominance and inversely related to diversity. The differential growth response of P. virgatum to soil N availability led to a higher degree of community similarity to native prairie in the reduced-N treatment than in the enriched-N treatment. There were no differences in plant community structure among the four whole plot-level heterogeneity treatments, which all exhibited the same degree of similarity to native prairie. Diversity and community heterogeneity in the whole-plot treatments appeared to be regulated by the dominant species' effect on light availability, rather than soil N heterogeneity per se. Our results indicate that a strong differential response of a dominant species to resource availability in a restored community can regulate community structure, diversity, and similarity to the native (or target) community, but the importance of resource heterogeneity in restoring diversity may be dampened in systems where a dominant species can successfully establish across a range of resource availability.

Conservation of Natural Resources↗
PubMed2001

Effects of kappa-opioid receptor agonists on long-term cocaine use and dopamine neurotransmission.

kappa-Opioid receptor agonists have been suggested as treatments for cocaine addiction based on studies showing that they block cocaine-related behaviors. To determine the effects of kappa-opioid receptor agonists on long-term behavioral effects associated with cocaine and the neurochemical bases underlying these effects, rats were treated with the selective kappa-opioid receptor agonist U-69593 ((+)(5alpha,7alpha,8beta)-N-methyl-N-[7-(1-pyrrolidinyl)-1 oxaspiro[4.5]dec-8-yl]-benzeneacetamide) alone or in combination with cocaine and locomotor activity was measured daily. In addition, dopamine transporter and dopamine receptor densities were measured using autoradiographic techniques, and tyrosine hydroxylase was measured using immunoautoradiographic techniques. Treatment with U-69593 with or without cocaine decreased locomotor activity. When challenged with cocaine after a 5-day treatment period, the effects of cocaine were markedly reduced in rats initially treated with U-69593 compared to vehicle. When U-69593 was administered five times with 3-day intervals, it alone had no effect on locomotor activity but still reduced activity associated with a cocaine injection. After five daily injections, U-69593 decreased dopamine transporter and dopamine D(2) receptor densities and increased tyrosine hydroxylase levels. These changes were not seen after the 3-day interval regimen, even though cocaine-induced activity was greatly reduced. These findings show that the effects associated with daily U-69593 treatment are attenuated if the drug is administered with a greater interval, while maintaining a blockade of cocaine-induced activity. In addition, U-69593 can block cocaine-induced locomotor effects without major perturbation of the dopamine system.

Analgesics↗
PubMed2001

Time course of changes in cocaine self-administration behavior in rats during immunization with the cocaine vaccine IPC-1010.

RATIONALE: Following a 6-week immunization period consisting of three biweekly injections of the cocaine vaccine IPC-1010, the reacquisition of cocaine self-administration behavior in rats was previously shown to be reduced in a manner that was dependant on serum antibody level. The present studies were conducted to examine additional issues relevant to the clinical use of the vaccine. OBJECTIVES: One experiment was conducted to address the issue of whether exposure to cocaine during the immunization period would influence the ability of the vaccine to block cocaine self-administration. A second experiment was conducted to determine if the reductions in drug-seeking behavior and drug intake by the vaccine were behaviorally specific, or if behavior maintained by a non-drug reinforcer would be similarly affected. METHODS: Identical second-order schedules of cocaine (1 mg/kg) or food pellet (45 mg) delivery were used in rats. In both studies, the time course of changes in behavior during the 6-week immunization period was examined in vaccine and alum-treated control rats following baseline and extinction conditions. RESULTS: The cocaine vaccine IPC-1010 induced average serum antibody levels of 0.07 mg/ml and significantly reduced self-administration behavior during the 2-week period following the third vaccine boost in a subgroup of rats with serum antibody levels greater than the average value. Cocaine self-administration behavior at this time point significantly correlated with serum antibody level. IPC-1010 did not alter responding maintained by food throughout the immunization period although serum antibody levels reached a similar average of 0.06 mg/ml in this group of rats. CONCLUSIONS: These findings suggest that the reductions in drug-seeking behavior and drug intake after immunization with IPC-1010 did not result from a reduced ability of the rats to respond on the lever. Furthermore, daily exposure to cocaine during the immunization period did not influence the ability of the vaccine to reduce cocaine self-administration behavior that emerged gradually over time. These findings also confirm the need for a sufficiently high antibody level to blunt the reinforcing effects of cocaine.

Animals↗
PubMed2001

Effects of nitric oxide synthase inhibitors on the discriminative stimulus effects of cocaine in rats.

RATIONALE: Nitric oxide synthase (NOS) inhibitors may modulate the discriminative stimulus effects of cocaine because they alter dopamine (DA) release. OBJECTIVES: The effects of the NOS inhibitors NG-nitro-L-arginine methyl ester (L-NAME) and 7-nitro-indazole (7-NI) were examined in experiments designed to better understand the mechanisms that may underlie the interactions between NOS inhibitors and cocaine. METHODS: Rats were trained to discriminate 10 mg/kg cocaine from saline, and then substitution and pretreatment tests with L-NAME and 7-NI were conducted. To determine if the combined effects of NOS inhibitors and cocaine might be related to DA mechanisms and/or to N-methyl-D-aspartate (NMDA) receptor mechanisms, substitution tests with other indirect DA agonists and NMDA antagonists were carried out in the presence and absence of L-NAME. In addition, the roles of the D1 and D2 families of DA receptors in mediating the cocaine-altering effects of L-NAME and 7-NI were examined in antagonism tests using SCH 23390 and haloperidol, respectively. RESULTS: The results demonstrated that neither NOS inhibitor alone substituted for the 10 mg/kg cocaine training dose, but when given as a pretreatment, 100 mg/kg L-NAME as well as 10 mg/kg 7-NI enhanced the discriminative stimulus and rate-decreasing effects of cocaine. L-NAME pretreatment also enhanced the potency of (+)-amphetamine and GBR 12909, but not MK-801, phencyclidine, or NPC 17742, for producing discriminative stimulus and rate-decreasing effects in substitution tests. Further testing showed that the cocaine-enhancing effects of L-NAME and 7-NI were attenuated by doses of haloperidol and SCH 23390 that minimally altered the effects of cocaine alone. CONCLUSIONS: These findings suggest that L-NAME and 7-NI may increase the potency of cocaine and other indirect DA agonists through a central mechanism whereby DA neurotransmission is directly enhanced by NOS inhibition.

Animals↗
PubMed2001

Seeking a simple measure of analgesia for mega-trials: is a single global assessment good enough?

We sought to investigate the potential of using a simple global estimation ('How effective do you think the treatment was?') as a measure of efficacy by comparing it with at least 50%maxTOTPAR (at least 50% of the maximum possible pain relief) in acute pain studies. One hundred and fifty randomized, double-blind trials included in 11 systematic reviews of single dose, oral analgesics for postoperative pain were used as a source of data. The relationship between the proportion of patients reporting the top two or three values on a five-point global scale and the proportion with at least 50%maxTOTPAR was investigated. Twenty-six trials provided data on the proportion reporting the top two categories (very good or excellent) and 27 gave data on the top three categories (good, very good or excellent). The relationship between the percentage of patients recording the top two categories on a five-point global scale and the proportion with at least 50%maxTOTPAR was fair (r(2)=0.67). That for the top three categories was less good (r(2)=0.57). Similar numbers-needed-to-treat were calculated for aspirin 600/650 mg and ibuprofen 400 mg using at least 50%maxTOTPAR and the top two categories. No real difference was seen in the correlation for standard wording compared to non-standard wording. Individual patient data were also used from four randomized, placebo-controlled, double-blind trials in postoperative pain. The frequency distribution for %maxTOTPAR was plotted for patients reporting each of the five categories on the global scale. A global assessment provides similar measures of analgesic efficacy as TOTPAR derived from hourly measurements, but the effects of adverse effects have yet to be understood.

Analgesia↗
PubMed2001

Kappa opioid agonists alter dopamine markers and cocaine-stimulated locomotor activity.

To better understand the influence of kappa-opioid agonists on the effects of cocaine, rats were treated with daily injections of the selective kappa-opioid agonist U-69593 or bremazocine. In combination with 10 mg/kg cocaine, both compounds, at a dose of 0.32 mg/kg, greatly diminished locomotor activity, and these effects were maintained over a period of 5 days. In addition, the response to a challenge injection of 10 mg/kg cocaine several days after the end of kappa-Opioid agonist treatment with or without cocaine was markedly reduced. When naltrexone was given in combination with U-69593, it blocked the reduction in cocaine-induced locomotor activity after U-69593 treatment alone. However, a single injection of either kappa-opioid agonist alone had no effect on cocaine-induced locomotion several days later (i.e. no long-term effects), suggesting that multiple injections of the kappa-opioid agonist are needed to reduce the locomotor activating effects of cocaine other than acutely. In addition, treatment with the kappa-opioid agonist U-69593 (0.32 mg/kg) over a 5-day period decreased dopamine transporter densities in the caudate putamen, and this was also blocked by co-administration of naltrexone.

Analgesics↗
PubMed2000

Single dose dextropropoxyphene, alone and with paracetamol (acetaminophen), for postoperative pain.

BACKGROUND: Patient surveys have shown that postoperative pain is often not managed well, and there is a need to assess the efficacy and safety of commonly used analgesics as newer treatments become available. Dextropropoxyphene is one example of an opioid analgesic in current use, and is widely prescribed for pain relief in combination with paracetamol under names such as Co-proxamol and Distalgesic. OBJECTIVES: To determine the analgesic efficacy and adverse effects of single dose oral Dextropropoxyphene alone and in combination with paracetamol (acetaminophen) for moderate to severe postoperative pain. SEARCH STRATEGY: Published reports were identified from: Medline (1966 - November 1996), Biological Abstracts (1985 - 1996), Embase (1980 - 1996), the Cochrane Library (Issue 4 1996), and the Oxford Pain Relief Database (1954 - 1994). Additional studies were identified from the reference lists of retrieved reports. Date of the most recent searches: July 1998. SELECTION CRITERIA: The inclusion criteria used were: full journal publication, postoperative pain, postoperative oral administration, adult patients, baseline pain of moderate to severe intensity, double-blind design, and random allocation to treatment groups which included dextropropoxyphene and placebo or a combination of dextropropoxyphene plus paracetamol and placebo. DATA COLLECTION AND ANALYSIS: Data were extracted by two independent reviewers, and trials were quality scored. Summed pain intensity and pain relief data were extracted and converted into dichotomous information to yield the number of patients with at least 50% pain relief. This was used to calculate the relative benefit and number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief. MAIN RESULTS: Six trials (440 patients) compared dextropropoxyphene with placebo and five (963 patients) compared dextropropoxyphene plus paracetamol 650 mg with placebo. For a single dose of dextropropoxyphene 65 mg in postoperative pain the NNT for at least 50% pain relief was 7.7 (95% confidence interval 4.6 to 22) when compared with placebo over 4-6 hours. For the equivalent dose of dextropropoxyphene combined with paracetamol 650 mg the NNT was 4.4 (3.5 to 5.6) when compared with placebo. These results were compared with those for other analgesics obtained from equivalent systematic reviews. Pooled data showed increased incidence of central nervous system adverse effects for dextropropoxyphene plus paracetamol compared with placebo. REVIEWER'S CONCLUSIONS: The combination of dextropropoxyphene 65 mg with paracetamol 650 mg shows similar efficacy to tramadol 100 mg for single dose studies in postoperative pain but with a lower incidence of adverse effects. The same dose of paracetamol combined with 60 mg codeine appears more effective but, with the slight overlap in the 95% confidence intervals, this conclusion is not robust. Adverse effects of both combinations were similar. Ibuprofen 400 mg has a lower (better) NNT than both dextropropoxyphene 65 mg plus paracetamol 650 mg and tramadol 100 mg.

Acetaminophen↗
PubMed2000

Single dose oral ibuprofen and diclofenac for postoperative pain.

BACKGROUND: Ibuprofen and diclofenac are two widely used non-steroidal anti-inflammatory (NSAID) analgesics. It is therefore important to know which drug should be recommended for postoperative pain relief. This review seeks to compare the relative efficacy of the two drugs, and also considers the issues of safety and cost. OBJECTIVES: To assess the analgesic efficacy of ibuprofen and diclofenac in single oral doses for moderate to severe postoperative pain. SEARCH STRATEGY: Randomised trials were identified by searching Medline (1966 to December 1996), Embase (1980 to January 1997), the Cochrane Library (Issue 3 1996), Biological Abstracts (January 1985 to December 1996) and the Oxford Pain Relief Database (1950 to 1994). Date of the most recent searches: July 1998. SELECTION CRITERIA: The inclusion criteria used were: full journal publication, postoperative pain, postoperative oral administration, adult patients, baseline pain of moderate to severe intensity, double-blind design, and random allocation to treatment groups which compared either ibuprofen or diclofenac with placebo. DATA COLLECTION AND ANALYSIS: Data were extracted by two independent reviewers, and trials were quality scored. Summed pain relief or pain intensity difference over four to six hours was extracted, and converted into dichotomous information yielding the number of patients with at least 50% pain relief. This was then used to calculate the relative benefit and the number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief. MAIN RESULTS: Thirty-four trials compared ibuprofen and placebo (3,591 patients), six compared diclofenac with placebo (840 patients) and there were two direct comparisons of diclofenac 50 mg and ibuprofen 400 mg (130 patients). In postoperative pain the NNTs for ibuprofen 200 mg were 3.3 (95% confidence interval 2.8 to 4.0) compared with placebo, for ibuprofen 400 mg 2.7 (2.5 to 3.0), for ibuprofen 600 mg 2.4 (1.9 to 3.3), for diclofenac 50 mg 2.3 (2.0 to 2.7) and for diclofenac 100 mg 1.8 (1.5 to 2.1). Direct comparisons of diclofenac 50 mg with ibuprofen 400 mg showed no significant difference between the two. REVIEWER'S CONCLUSIONS: Both drugs work well. Choosing between them is an issue of dose, safety and cost.

Analgesics, Non-Narcotic↗
PubMed2000

Radiotherapy for the palliation of painful bone metastases.

BACKGROUND: Radiotherapy is used commonly to provide pain relief for painful bone metastases, and there is a perception that of the three-quarters of patients who achieve pain relief, half of these stay free from pain. However, the precise contribution from radiotherapy may be unclear because of difficulties in assessing the numbers of people achieving relief, the extent of relief and its duration, and the influence of other contemporaneous interventions, such as analgesics. OBJECTIVES: To assess pain relief from: 1. localised bone metastases achieved by radiotherapy, comparing the efficacy of different fractionation schedules 2. more generalised metastatic disease achieved by radiotherapy or radioisotopes. SEARCH STRATEGY: Studies were identified by searching Medline (1966 to August 1998), Embase (1980 to 1998), the Cochrane Library (1998 Issue 3) and the Oxford Pain Relief Database (1950 to 1994). SELECTION CRITERIA: The inclusion criteria used were: full journal publication, patients with pain due to bone metastases, and random allocation to a radiotherapeutic intervention (either external irradiation or administration of radioisotopes). DATA COLLECTION AND ANALYSIS: The number of patients achieving complete pain relief and at least 50% at one month were compared with an assumed natural history of 1 in 100 patients achieving pain relief without treatment to obtain the number-needed-to-treat (NNT). Summed pain relief or pain intensity difference over four to six hours was extracted, converted into dichotomous information yielding the number of patients with at least 50% pain relief, and used to calculate the relative benefit and the NNT for one patient to achieve at least 50% pain relief. MAIN RESULTS: Twenty trials reported on 43 different radiotherapy fractionation schedules and eight studies of radioisotopes. Radiotherapy produced complete pain relief at one month in 395/1580 (25%) patients, and at least 50% relief in 788/1933 (41%) patients at some time during the trials. There were no differences in the proportions of patients achieving these outcomes between single or multiple fraction schedules. The number-needed-to-treat (NNT) to achieve complete relief at one month (compared with an assumed natural history of 1 in 100 patients whose pain resolved without treatment) was 4.2 (95% CI 3.7-4.7). No pooled estimates of speed of onset of relief, or of its duration, could be obtained. In the largest trial (759 patients) 52% of those who had complete relief had achieved it within four weeks, and the median duration of complete relief was 12 weeks. For more generalised disease, radioisotopes produced similar analgesic results to external irradiation. Adverse effect reporting was poor. There were no obvious differences between the various fractionation schedules in the incidence of nausea and vomiting, diarrhoea or pathological fractures. REVIEWER'S CONCLUSIONS: Radiotherapy is clearly effective at reducing pain from painful bone metastases. There was no evidence of any difference in efficacy between different fractionation schedules, nor indeed of a dose-response with total dose of radiation. For treatment of generalised bone pain both hemibody irradiation and radioisotopes can reduce the number of painful new sites.

Bone Neoplasms↗
PubMed2000

Single dose oral aspirin for acute pain.

BACKGROUND: Aspirin has been known to be an effective analgesic for many years and is commonly used throughout the world for many different pain conditions. It is important for both prescribers and patients to have the best possible information about the efficacy and safety of analgesics, and this need is reflected in patient surveys which show that postoperative pain is often poorly managed. We also need to benchmark relative efficacy and safety of current analgesics so that we can compare them with new analgesics. OBJECTIVES: To quantitatively assess the analgesic efficacy and adverse effects of a single-dose of aspirin in acute pain of moderate to severe intensity. SEARCH STRATEGY: Randomised trials were identified by searching Medline (1966 to March 1998), Embase (1980 to January 1998), the Cochrane Library (Issue 1,1998) and the Oxford Pain Relief Database (1950 to 1994). SELECTION CRITERIA: The inclusion criteria used were: full journal publication, postoperative pain or a mixture of postoperative and acute trauma pain, oral administration, adult patients, baseline pain of moderate to severe intensity, double-blind design, and random allocation to treatment groups which compared aspirin with placebo. DATA COLLECTION AND ANALYSIS: Summed pain relief or pain intensity difference over four to six hours was extracted, and converted into dichotomous information yielding the number of patients with at least 50% pain relief. This was then used to calculate the relative benefit and the number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief. MAIN RESULTS: Seventy-two randomised single-dose trials met our inclusion criteria, with 3253 patients given aspirin, and 3297 placebo. Significant benefit of aspirin over placebo was shown for aspirin 600/650 mg, 1000 mg and 1200 mg, NNTs for at least 50% pain relief of 4.4 (4.0 to 4.9), 4.0 (3.2 to 5.4) and 2.4 (1.9 to 3.2) respectively. Single-dose aspirin 600/650 mg produced significantly more drowsiness and gastric irritation than placebo, with a number-needed-to-harm (NNH) of 28 (19 to 52) and 38 (22 to 174) respectively. Type of pain model, pain measurement, sample size, quality of study design, and study duration had no significant impact on the results. REVIEWER'S CONCLUSIONS: Aspirin is an effective analgesic for acute pain of moderate to severe intensity with a clear dose-response. Drowsiness and gastric irritation were seen as significant adverse effects even though the studies were single-dose. The pain relief achieved with aspirin was very similar milligram for milligram to that seen with paracetamol.

Acute Disease↗
PubMed2000

Evaluation of anti-cocaine antibodies and a cocaine vaccine in a rat self-administration model.

RATIONALE: Previous pre-clinical studies with an anti-cocaine monoclonal antibody left open several issues critical to assessing the effectiveness of a vaccine for altering cocaine self-administration behavior. OBJECTIVES: The objectives of this study were to determine, first, whether changes in self-administration behavior would be systematically related to antibody level and, second, how the antibody affected the self-administration of different doses of cocaine. METHODS: Two experiments were conducted using a second-order schedule of drug delivery in rats. The first was a passive-administration study using the anti-cocaine monoclonal antibody MO240 to examine the relationship between antibody level and cocaine self-administration behavior, and the second was an active-immunization study to examine the efficacy of the cocaine vaccine IPC-1010 for blocking various doses of self-administered cocaine. RESULTS: The passive-administration experiment with control and 4-mg or 12-mg MO240 treatments showed that antagonism of the 1 mg/kg cocaine training dose was dependent on antibody level. In animals whose serum antibody levels were sustained above 0.05 mg/ml, there was a sufficient amount of antibody to reduce drug-seeking behavior and drug intake. In the active-immunization experiment, the cocaine vaccine IPC-1010 induced average serum antibody levels of 0.08 mg/ml and reduced the reacquisition of behavior by 1 mg/kg cocaine. Antagonism of cocaine self-administration after immunization was evident across a range of doses of cocaine and was only apparent in animals whose serum antibody levels exceeded 0.05 mg/ml. Furthermore, there was no evidence that the antagonism was surmountable within the dose range examined (up to 5.6 mg/kg). CONCLUSIONS: Antagonism of cocaine self-administration across a range of doses is feasible after immunization with a cocaine vaccine as long as antibody levels are of a sufficient concentration.

Animals↗
PubMed2000

Antidepressants and anticonvulsants for diabetic neuropathy and postherpetic neuralgia: a quantitative systematic review.

To determine the relative efficacy and adverse effects of antidepressants and anticonvulsants in the treatment of diabetic neuroapathy and postherpetic neuralgia, published reports were identified from a variety of electronic databases, including Medline, EMBASE, the Cochrane Library and the Oxford Pain Relief Database, and from two previously published reviews. Additional studies were identified from the reference lists of retrieved reports. The relative benefit (RB) and number-needed-to-treat (NNT) for one patient to achieve at least 50 % pain relief was calculated from available dichotomous data, as was the relative risk (RR) and number-needed-to-harm (NH) for minor adverse effects and drug related study withdrawal. In diabetic neuropathy, 16 reports compared antidepressants with placebo (491 patient episodes) and three compared anticonvulsants with placebo (321). The NNT for at least 50 % pain relief with antidepressants was 3.4 (95 % confidence interval 2.6-4. 7) and with anticonvulsants 2. 7 (2. 2-3. 8). In postherpetic neuralgia, three reports compared antidepressants with placebo (145 patient episodes) and one compared anticonvulsants with placebo (225), giving an NNT with antidepressants of 2.1 (1. 7-3) and with anticonvulsants 3.2 (2.4-5). There was little difference in the incidence of minor adverse effects with either antidepressants or anticonvulsants compared with placebo, with 1VH (minor) values of about 3. For drug-related study withdrawal, antidepressants had an NNH (major) of 17 (11-43) compared with placebo, whereas with anticonvulsants there was no significant difference from placebo. Antidepressants and anticonvulsants had the same efficacy and incidence of minor adverse effects in these tzoo neuropathic pain conditions. There was no evidence that selective serotonin reuptake inhibitors (SSRIs) were better than older antidepressants, and no evidence that gabapentin was better than older anticonvulsants. In these trials patients were more likely to stop taking antidepressants than anticonvulsants because of adverse effects.

Anticonvulsants↗
PubMed2000

A prospective study of the effects of irradiation on the carotid artery.

OBJECTIVES/HYPOTHESIS: To prospectively assess the effects of irradiation on the carotid artery in patients with head and neck cancer, as a possibly relevant factor in cancer treatment planning. STUDY DESIGN: Prospective study from a tertiary care academic setting on university (22 patients) and Veterans Affairs (14 patients) hospital patients; 1-year follow-up, including comparison of study data with age-matched and sex-matched control subjects from epidemiological studies. METHODS: Thirty-six patients with head and neck cancer who underwent therapeutic neck irradiation were examined by high-resolution ultrasound before and 1 year after treatment. Twelve patients were also studied at 2 years. Measurements included the intima-media thickness (IMT) of the carotid artery wall, the degree of stenosis as estimated from velocity measurements, and the presence and size of plaque. RESULTS: The pretreatment carotid IMT at baseline was 0.68 mm and was comparable to age-matched and sex-matched control subjects. Significant increase in the IMT was observed on both the left (0.67 vs. 0.84 mm) and the right (0.7 vs. 0.87 mm) sides (P < .001) 1 year after irradiation. In 12 patients who completed 24 months of follow-up the carotid IMT continued to significantly increase statistically compared with that at the first year after treatment (left side, 0.79 vs. 0.85 mm, P = .037; right side, 0.79 vs. 0.95 mm, P = .014). Statistically significant thickening of the carotid wall developed in all 36 patients by 1 year. Two patients experienced post-treatment neurological events and an area of stenosis greater than 75%. CONCLUSIONS: Neck irradiation significantly increases the thickness of the carotid wall during the first year after treatment--on average, 21 times more than in epidemiologically matched control volunteers. This phenomenon should be taken into consideration when planning treatment for the node-negative (NO) neck.

Carcinoma, Squamous Cell↗
PubMed2000

A liquid-stable reagent for lactic acid levels. Application to the Hitachi 911 and Beckman CX7.

We evaluated the use of a new lactate oxidase-based reagent for the determination of serum and plasma lactic acid levels with the Hitachi 911 (Roche Diagnostics, Indianapolis, IN) and the Beckman CX7 (Beckman Instruments, Brea, CA). Evaluation studies demonstrated on-board stability of at least 3 months and a calibration stability of more than 5 months. Within- and between-day imprecision of this reagent was less than 2% for both applications. The reagent is free of the deleterious effects of triglyceride up to levels of 1,400 mg/dL (15.8 mmol/L), bilirubin to concentrations of 24.6 mg/dL (420 mumol/L), and hemoglobin, from lysed erythrocytes, to levels of more than 0.3 g/dL (3.0 g/L). When used on the Hitachi 911 for the determination of plasma lactate concentrations, the reagent correlates with the Dade aca III (Dade International, Deerfield, IL). When applied to the Beckman CX7 for the determination of serum lactate levels, the method correlates with the Beckman method.

Ampyrone↗
PubMed1999

Exertional heat illness and hyponatremia in hikers.

We compared clinical presentation and course of exercise-associated hyponatremia with heat exhaustion among summertime hikers in Grand Canyon National Park. Cases were selected from among hikers who requested medical help from the National Park Service Emergency Medical Service (EMS) or who presented to the medical clinic on the rim of the canyon with complaints related to exercise in the heat. Of 44 patients who had serum samples analyzed, 7 had hyponatremia with clinically significant symptoms and serum sodium levels <130 mmol/L: 3 had grand mal seizures, 2 had other major central nervous system disorders, and 2 had minor neurological symptoms. Seizures and change of mental status distinguished hyponatremia, (P = 0.0002). Indirect evidence suggests that hyponatremic patients were hyperhydrated. Other common symptoms included nausea, vomiting, headache, and dizziness, but these symptoms did not predict the level of serum sodium. When exercise in the heat is prolonged, hyponatremia is suggested either by altered mental status or by seizures without hyperpyrexia or hypoglycemia. No mortality or long-term morbidity occurred in any of these cases of hyponatremia.

Adult↗
PubMed1999

Reporting of adverse effects in clinical trials should be improved: lessons from acute postoperative pain.

We assessed the quality of assessment and reporting of adverse effects in randomized, double-blind clinical trials of single-dose acetaminophen or ibuprofen compared with placebo in moderate to severe postoperative pain. Reports were identified by systematic searching of a number of bibliographic databases (e.g., MEDLINE). Information on adverse effect assessment, severity and reporting, patient withdrawals, and anesthetic used was extracted. Compliance with former guidelines for adverse effect reporting was noted. Fifty-two studies were included; two made no mention of adverse effects. No method of assessment was given in 19 studies. Twenty trials failed to report the type of anesthetic used, eight made no mention of patient withdrawals, and nine did not state the severity of reported adverse effects. Only two studies described the method of assessment of adverse effect severity. When all adverse effect data were pooled, significantly more adverse effects were reported with active treatment than with placebo. For individual adverse effects, there was no difference between active (acetaminophen 1000 mg or ibuprofen 400 mg) and placebo; the exception was significantly more somnolence/drowsiness with ibuprofen 400 mg. Ninety percent of trials reporting somnolence/drowsiness with ibuprofen 400 mg were in dental pain. All studies published after 1994 complied with former guidelines for adverse effect reporting. Different methods of assessing adverse effects produce different reported incidence: patient diaries yielded significantly more adverse effects than other forms of assessment. We recommend guidelines for reporting adverse effect information in clinical trials.

Acetaminophen↗
PubMed1998

Single-dose dextropropoxyphene in post-operative pain: a quantitative systematic review.

OBJECTIVE: To determine the analgesic efficacy and adverse effects of single-dose oral dextropropoxyphene alone and in combination with paracetamol for moderate to severe post-operative pain. METHODS: Published reports were identified from a variety of electronic databases including MEDLINE, Biological Abstracts, EMBASE, the Cochrane Library and the Oxford Pain Relief Database. Additional studies were identified from the reference lists of retrieved reports. Summed pain intensity and pain relief data were extracted and converted into dichotomous information to yield the number of patients with at least 50% pain relief. This was used to calculate the relative benefit and number-needed-to-treat for one patient to achieve at least 50% pain relief. Six reports (440 patients) compared dextropropoxyphene with placebo and five (963 patients) compared dextropropoxyphene plus paracetamol 650 mg with placebo. RESULTS: For a single dose of dextropropoxyphene 65 mg in post-operative pain the number-needed-to-treat for at least 50% pain relief was 7.7 (95% confidence interval 4.6 to 22) when compared with placebo over 4-6 h. For the equivalent dose of dextropropoxyphene in combination with paracetamol 650 mg the number-needed-to-treat was 4.4 (3.5 to 5.6) when compared with placebo. Pooled data showed increased incidence of central nervous system adverse effects for dextropropoxyphene plus paracetamol when compared with placebo. A rank order of single-dose analgesic effectiveness in post-operative pain of moderate to severe intensity obtained from similar systematic reviews is presented. CONCLUSION: Dextropropoxyphene 65 mg plus paracetamol 650 mg has a similar analgesic efficacy to that of tramadol 100 mg but with a lower incidence of adverse effects. Ibuprofen 400 mg has a lower (better) number-needed-to-treat than both dextropropoxyphene 65 mg plus paracetamol 650 mg and tramadol 100 mg.

Acetaminophen↗