Do Patient Demographics and Performance Status Influence Opioid Dose in Cancer Pain?

Context: There is limited evidence on the role of objective parameters in influencing analgesic use in cancer pain management.Objective: To investigate the significance of objective parameters (age, male/female and performance status) in influencing opioid dose. Methods: We conducted a retrospective cross-sectional audit of adult inpatients with metastatic cancer at a major cancer centre from 1 January 2016 to 31 December 2018, who were prescribed slow release opioids for cancer pain on discharge. Main outcome measures were demographics (age, male/female and performance status), oral morphine equivalent daily dose (oMEDD) and adjuvant analgesic use. Results: Of the 7,747 eligible records, 215 patient records fulfilled inclusion criteria. Older patients (≥75 years) received half of the median oMEDD dose (30 mg) compared to their youngest counterparts (60 mg oMEDD in age ≤50 years) (P = .003). No significant differences were observed between oMEDD and male/female and performance status. Conclusion: Older patients are prescribed half the opioid dose compared to their younger counterparts. This highlights the importance of vigilance in opioid prescribing in the elderly in order to balance side effects with under treatment. Although no other significant relationships were observed, future studies comparing objective patient parameters with opioid prescription may uncover other at risk populations.

The metabolism of phospholipids in mouse brain slices

1. Slices of mouse brain grey matter were incubated with [(32)P]phosphate and [1-(14)C]acetate. Doubly labelled phospholipids were extracted from subcellular fractions prepared from the slices in a mixture of metabolic inhibitors, under conditions where there was negligible change in radioactive labelling during the preparation. Two tissue fractions were studied in detail; one contained a high proportion of mitochondria and the other was mainly microsomal. 2. In all tissue fractions the highest incorporations of both [(32)P]phosphate and [1-(14)C]acetate occurred into phosphatidylcholine. 3. After incubation for 1hr., the (32)P/(14)C ratios for phosphatidylcholine, phosphatidylethanolamine and phosphatidic acid in the mitochondrial fraction were similar to those in the microsomal fraction. 4. The (32)P/(14)C ratios were similar in phosphatidylcholine and phosphatidylethanolamine and much lower than those in phosphatidic acid and phosphatidylinositol.

The concept of resistance in self psychology

Self psychology views resistances as protecting a vulnerable self. Resistances are seen as efforts to maintain levels of organization that patients have achieved within the context of their traumatic life situation. Patients feel able to move forward in the treatment when the importance of their need to maintain their developmental position is understood. This view is in contrast to the traditional view of resistances as treatment interferences that must be overcome as they defend against awareness of impulses and allow for unconscious instinctual gratification.

'Neurosis' and the personal social environment. The effects of a time-limited course of intensive day care

The Interview Schedule for Social Interactions (ISSI) was used to assess the social environment of 65 British inner-city patients suffering from severe neurotic disorder; all patients were offered a 12-week course of intensive day treatment with an educational and psychodynamic basis. Compared with a general population in Canberra, the neurosis sufferers had lower (morbid) scores on the ISSI for the extent and quality of their social relationships. Of the 34 subjects who completed treatment and attended for the post-treatment investigation, 21 attained a PSE score below the level for 'caseness'. Twenty-five subjects who attended for follow-up at 18-24 months had improved significantly on all four of the standard ISSI measures, although they had not done so immediately after treatment. This suggests that although symptoms may improve at the time of treatment, social relationships improve only over several months.

Growth of microorganisms in total nutrient admixtures

It has been reported that intravenous fat emulsions, because of their isotonicity and neutral pH, support microbial growth, but traditional parenteral nutrition solutions, being hypertonic and more acidic, are not as supportive. To date, few studies have documented microbial growth in total nutrient admixtures (TNA) containing dextrose, amino acids, fat, electrolytes, vitamins, and trace elements. This study was undertaken to analyze the growth of Staphylococcus aureus, Candida albicans and four gram-negative enteric bacilli in three different nutrient admixtures, with and without the inclusion of 5% fat emulsion. The composition of the admixtures was either 5, 10, or 25% dextrose; either 0 or 5% fat; and 3% amino acids, electrolytes, vitamins, and trace elements. All admixtures were innoculated with 100 colony-forming units per milliliter, incubated at room (25 degrees C) or refrigerated (4 degrees C) temperature, with samples withdrawn at 0, 3, 6, 12, 24, and 48 hours and plated in triplicate. Only C. albicans demonstrated any significant growth regardless of fat content. The pH of the admixtures was similar (acidic), and all solutions were hypertonic and found to inhibit bacterial growth. Conclusions suggest that TNA, when formulated with normal concentrations of additives, is no more likely to support growth of contaminant organisms than the traditional solutions. This contradicts the notion that the addition of fat to total parenteral nutrition will enhance the ability of these admixtures to support microbial growth.

Intraoral effects of a fluoride-releasing device on acid-softened enamel

Among the anticaries benefits of fluorides is the remineralization of incipient carious lesions. There is increasingly convincing evidence that low-potency fluoride agents applied frequently are effective in remineralizing early carious lesions. This study of in vivo remineralization used an intraoral appliance with demineralized enamel slabs mounted in the appliance and an innovative method of fluoride delivery, the fluoride-releasing device, which releases a controlled amount of fluoride (0.3 mg fluoride every 24 hours) on exposure to saliva. After control and treatment periods of 7 and 30 days, the enamel specimens were removed from the appliance and evaluated for microhardness, acid resistance, and fluoride uptake. The treated specimens significantly exceeded the values of their corresponding controls in all parameters measured, indicating that considerable remineralization of the treated enamel had occurred at both 7 and 30 days. Although the longer period of treatment produced greater results, considerable effects were observed after 7 days. This model system provided for an in vivo environment to study the effects of treatment of the FRD and allowed for subsequent recovery of the enamel specimens for evaluation. The results of this study are encouraging with respect to the efficacy of a fluoride-releasing device but indicate that subsequent clinical testing of the effects of FRDs on incipient carious lesions in the natural dentition of human subjects is necessary.

The intracellular location of a Ca2+-stimulated phospholipase A1 in rat brain

Rat brain contains a phospholipase A1 which hydrolyzes phosphatidylethanolamine with a pH optimum of 9.5. The enzyme is stimulated by CaCl2 and inhibited by sodium taurocholate and Triton X-100. The subcellular distibution of the enzyme is similar to that of lactate dehydrogenase indicating the location of the phospholipase in the soluble cytoplasm in vitro.

The acylation of lysophosphatidylcholine by subcellular fractions of guinea-pig cerebral cortex

The acylation of lysophosphatidylcholine by isolated subcellular fractions of guinea-pig cerebral cortex has been determined. The microsomal fraction contained the highest acylation activity, in terms of both specific and total activity. In all particulate fractions, including synaptic plasma membrane and mitochondria, there was a high correlation (correlation coefficient r = 0.90; P less than 0.001) between acylation and the activity of the microsomal enzyme, NADPH-cytochrome c reductase. No correlation existed between acylation and the activities of (Na+ + K+)-ATPase, acetylcholinesterase or succinate dehydrogenase. Acyl-CoA synthetase and lysophosphatidylcholine/acyltransferase, the individual enzymes responsible for acylation were enriched in the microsomal fraction. The activities of both enzymes in subcellular fractions correlated well with those of NADPH-cytochrome c reductase, with the exception that acyl-CoA synthetase activity in the mitochondrial fraction was largely independent of endoplasmic reticulum. Neither synaptic plasma membranes nor mitochondria appeared to possess significant amounts of acyltransferase activity. The results indicate that the acylation of lysophosphatidylcholine is confined to the endoplasmic reticulum, and that activity present in the synaptic plasma membrane or mitochondrial fraction is attributable to microsomal contamination.

Net activity of phospholipase A2 in brain and the lack of stimulation of the phospholipase A2-acylation stem

Certain observations reported previously from this laboratory have not proved reproducible. These are (1) the relatively rapid hydrolysis of added phosphatidylcholine by phospholipase A2 of tissue from the cerebral cortex of the guinea pig and (2) the stimulation by 10 micron-noradrenaline and by 1.0nM-cyclic AMP of the phospholipase A2-acylation system of isolated synaptic membranes.

The stimulation by synaptic transmitters of the incorporation of oleate into the phospholipid of synaptic membranes

Noradrenaline stimulated the incorporation of oleate into choline glycerophospholipids of guinea-pig brain synaptic membranes incubated in sodium phosphate buffer. In the presence of 1 mm-NaF, noradrenaline stimulated the incorporation of oleate into the choline glycerophospholipids, phosphatidylinositol, ethanolamine glycerophospholipids, phosphatidylserine and phosphatidic acid of synaptic membranes incubated in 10 mm-Tris-HCl buffer. In Tris-CHl containing 1 mm-NaF, stimulation of incorporation of oleate into choline glycerophospholipids by noradrenaline was enhanced by ATP, CaCl2, MgCl2 and CoA plus dithiothreitol. The optimum concentration of CaCl2 for stimulation by 10 mum-noradrenaline was 10 mum. In the presence of CaCl2, the optimum concentration of ATP-2MgCl2 was in the range 0.1-1 mm. Acetylcholine, carbamoylcholine, 5-hydroxytryptamine, dopamine, histamine and gamma-aminobutyric acid also stimulated the incorporation of oleate into choline glycerophospholipids of synaptic membranes. Sigmoidal dose-response curves were obtained, similar to those obtained previously for stimulation by the same agonists of the hydrolysis of phosphatidylcholine by phospholipase A2 (Gullis & Rowe, 1975a). The initial rate of transfer of oleate from oleoyl-CoA to choline glycerophospholipid was similar to the initial rate of transfer from oleate-albumin, stimulated by noradrenaline. Transfer of oleate from oleoyl-CoA was not appreciably stimulated by noradrenaline, but was stimulated by ATP and MgCl2.

The stimulation of the phospholipase A2-acylation system of synaptic membranes of brain by cyclic nucleotides

Hydrolysis of phosphatidylcholine by phospholipase A2 of synaptic membranes i n Tris-CHl buffer was stimulated by cyclic AMP, cyclic GMP, cyclic CMP, cyclic UMP and adenosine (0.1 mm). In the presence of 1 mm-NaF and cofactors, the same cyclic nucleotides and adenosine (10 mm) stimulated the incorporation of added oleate into the choline glycerophospholipids of synaptic membranes. Cyclic AMP and noradrenaline stimulated the incorporation of added oleate into position 2 of choline glycerophospholipid. Stimulation of net acylation was increased by preincubation in conditions which stimulated hydrolysis of phosphatidylcholine. Cyclic AMP only slightly stimulated the transfer of oleate from oleoyl-CoA into choline glycerophospholipid. The optimum concentration of CaCl2 for the stimulation of hydrolysis by phospholipase A2 by cyclic AMP was 1 mum. Stimulation of the incorporation of added oleate was maximal in the CaCl2 concentration range 1 mum-1mm. MgCl2 also enhanced stimulations, maximum effects being obtained with concentrations of 10 mum and 0.5 mm for hydrolysis by phospholipase A2 and incorporation of added oleate respectively. ATP enhanced the stimulation of incorporation of oleate but had no effect on the cyclic nucleotide stimulation of hydrolysis of added phosphatidylcholine by phospholipase A2. Adenosine, guanosine, ADP and 5'-AMP (all at 1 mm) inhibited the stimulation of incorporation of oleate by cyclic nucleotides and inhibited the transfer of oleate from oleoyl-CoA to phospholipid. They did not inhibit the stimulation of hydrolysis of added phosphatidylcholine (by phospholipase A2) by cyclic nucleotides, but inhibited the stimulation by noradrenaline, acetylcholine, 5-hydroxytryptamine, dopamine (3,4-dihydroxyphenethylamine) and histamine. Preincubation of synaptic membranes in the water or buffer increased the net activity of phospholipase A2. Preincubation with a mixture of ATP and MgCl2 increased the initial rate of acylation of membrane lipid.

The stimulation by transmitter substances and putative transmitter substances of the net activity of phospholipase A2 of synaptic membranes of cortex of guinea-pig brain

1. The distribution of the hydrolyses of phosphatidylcholine by phospholipase A2 and phospholipase A1, and the hydrolysis of lysophosphatidylcholine by lysophospholipase, in subcellular and subsynaptosomal fractions of cerebral cortices of guinea-pig brain, was determined. 2. Noradrenaline stimulated hydrolysis by phospholipase A2 in whole synaptosomes, synaptic membranes and fractions containing synaptic vesicles. 3. Stimulation of hydrolysis by phospholipase A2 in synaptic membranes by noradrenaline was enhanced by CaCl2, and by a mixture of ATP and MgCl2. The optimum concentration of CaCl2, in the presence of ATP and MgCl2, for stimulation by 10 muM-noradrenaline was in the range 1-10muM. The optimum concentration for ATP-2MgCl2 in the presence of 1 muM-CaCl2 was in the range 0.1-1mM. 4. Hydrolysis by phospholipase A2 of synaptic membranes was also stimulated by acetylcholine, carbamoylcholine, 5-hydroxytryptamine, dopamine (3,4-dihydroxyphenethylamine), histamine, psi-aminobutyric acid, glutamic acid and aspartic acid. With appropriate concentrations of cofactors, sigmoidal dose-response curves were obtained, half-maximum stimulations being obtained with concentrations of stimulant in the range 0.1-1muM. 5. Taurine also stimulated hydrolysis of phosphatidylcholine by phospholipase A2. There were only slight stimulations with methylamine, ethylenediamine or spermidine. No stimulation was obtained with glucagon.

Glyceride lipases in nerve endings of guinea-pig brain and their stimulation by noradrenaline, 5-hydroxytryptamine and adrenaline

1. Combined guinea-pig cortex and cerebellum was shown to contain triglyceride lipase, diglyceride lipase and monoglyceride lipase, which were assayed by the release of [1-(14)C]palmitate from [1-(14)C]palmitoylglycerol esters. Triglyceride lipase and diglyceride lipase were found in all particulate fractions. 2. With osmotically ruptured synaptosomes the rates of release of palmitate from glyceryl tripalmitate and glyceryl dipalmitate were 7-25mumol/h per g of protein and 0.18-0.69mmol/h per g of protein respectively. The logarithm of the rate of hydrolysis of glyceryl monopalmitate increased linearly with the logarithm of protein concentration. The pH optima of triglyceride lipase and diglyceride lipase were between 7 and 8. The pH optimum for monoglyceride lipase was approx. 8. 3. Triglyceride lipase and diglyceride lipase of osmotically ruptured synaptosomes were stimulated by noradrenaline, 5-hydroxytryptamine and adrenaline. Triglyceride lipase of isolated synaptic membranes was stimulated by 0.01-1mm-noradrenaline. Aging of membranes at 0 degrees C decreased activity, which could still be stimulated by noradrenaline. Diglyceride lipase of isolated membranes was stimulated by 1mum-1mm-noradrenaline. The activity of triglyceride lipase in isolated synaptic vesicles was diminished by 1mm-5-hydroxytryptamine.

Stimulation of the production of unesterified fatty acids in nerve endings of guinea-pig brain in vitro by noradrenaline and 5-hydroxytryptamine

1. Noradrenaline (1mm) and 5-hydroxytryptamine (1mm) stimulated the production of unesterified palmitate, oleate, stearate and arachidonate in nerve endings (synaptosomes) isolated from combined guinea-pig cerebral cortex and cerebellum. 2. Iproniazid phosphate (0.36mm) increased the concentrations of the same acids in osmotically ruptured synaptosomes. Further addition of 1mm-noradrenaline or 1mm-5-hydroxytryptamine reversed this increase. 3. Noradrenaline (0.01mm) stimulated the production of unesterified fatty acids in isolated synaptic membranes. 5-Hydroxytryptamine (0.01mm) stimulated the production of unesterified fatty acids in synaptic membranes and synaptic vesicles.