The accuracy of remembering chronic pain

Twelve chronic pain patients were employed in an investigation of the accuracy of memory for chronic pain. Subjects first made pain ratings before entering a treatment program. At dismissal 3–11 weeks later they were asked to remember how much pain they had had at baseline. Results show that patients remembered having significantly more pain than they actually rated during the baseline period. Caution is therefore warranted when using post-hoc pain measures with chronic pain patients.     

Perspectives in the control of chronic pain by nutritional manipulation

The role of cental neurotransmitters in mood, behavior and emotion are briefly reviewed. Some neurotransmitters, such as norepinephrine and serotonin, have been implicated in both the determination of pain threshold and the behavioral responses to painful; stimuli. A number of experiments have indicated that brain serotonin can be increased through administration of tryptophan, the dietary precursor of serotonin. Other dietary amino acids have also been found to alter pain tolerance thresholds. This paper reviews the evidence for, and the possible future use of, dietary manipulation to control chronic pain.     

Depression in chronic pain patients: relation to pain, activity, and sex differences

Depression is commonly reported among chronic pain patients and receiving increased attention from clinicians and researchers. There is, however, little empirical evidence concerning variables that differentiate depressed from non-depressed chronic pain patients, and whether depression is related to factors such as gender, pain report, and activity. As part of a study to address these questions, 63 chronic pain patients completed daily diaries of activity, pain levels, and medication intake, and completed questionnaires and interviews assessing depression, medical history, and demographic variables. Male and female depressed and non-depressed chronic pain patients did not differ on demographic and medical history data, but sex differences were found in patterns of the relationships of depression, activity, and pain. For women, depression was closely related to pain report, whereas for men depression was more strongly related to impairment of activity. Pain report was related only minimally to activity for male and female patients. Implications of the results of behavioral research on depression in chronic pain patients are discussed. Researchers are urged to carefully consider sex differences in future research with chronic pain patients.     

A simplified assay method of superoxide dismutase activity for clinical use.

A simple and inexpensive assay method of superoxide dismutase (SOD) activity of various biological materials has been developed. SOD activity can easily be measured by reading the medium's intense absorbance directly, and many samples can be treated in a short time using a reaction stopper which acts for a long time. Reproducibility of the assay method was excellent for the sample from an individual estimated at two different times (a week to a month) and the coefficient of variance was 5.1%. The mean and standard deviation of SOD activities of 45 blood samples from normal Japanese males 32.9 +/- 10.5 microgram per ml of blood; estimated using bovine SOD standard. The SOD activity of the fluid from lavaged lungs was 15.7 +/- 1.8 microgram/ml, and that of lung tissue homogenates from rats was 2.85 +/- 0.66 microgram/mg of protein.     

Memory for pain: relation between past and present pain intensity

Memory for the intensity of past physical pain depends critically on the intensity of present pain. When their present pain intensity was high, patients with chronic headaches of myofascial origin rated their maximum, usual, and minimum levels of prior pain as being more severe than their hourly pain diaries indicated. When their present pain intensity was low, the same patients remembered all 3 levels of prior pain as being less severe than they actually had been. The results show that pain produces systematic distortions of memory similar to those associated with alterations of affect or mood, and suggest a resolution to a conspicuous conflict in the current pain literature.     

Microdetermination of methylmalonic acid and other short chain dicarboxylic acids by gas chromatography: use in prenatal diagnosis of methylmalonic acidemia and in studies of isovaleric acidemia.

We have developed a sensitive gas-chromatographic method for the determination of methylmalonic acid and other short chain dircarboxylic acids in biological samples. The method is based on the isolation of the short chain dicarboxylic acid fraction by Dowex 3 X 4 column chromatography followed by gas-chromatography analysis of these acids as methyl esters. 2-n-Pentyl-malonic acid is used as an internal standard. With this method, methylmalonic, succinic and methylsuccinic acids were consistently detected and accurately measured in urine and serum from normal subjects; the identity of these acids being verified by mass spectroscopy. The method's sensitivity permitted its used in the prenatal diagnosis of methylmalonic acidemia by measuring methylmalonic acid in urine and amniotic fluid from three pregnant heterozygous women at risk. One affected (vitamin B-12 responsive type) and two unaffected fetuses were correctly diagnosed prenatally as judged by postnatal investigations. The amount of methylmalonic acid in urine and amniotic fluid was distinctly increased (2 to 14 times normal) in the former and consistently normal in the latter two cases during the third trimester of pregnancy. Effect of prenatal therapy with large doses of vitamin B-12 was closely followed in the first case using analyses of multiple maternal urine specimens. Urinary methylsuccinic acid excretion was studied in two cases with isovaleric acidemia. It was normal in a sample from a patient in remission but was increased seven fold over control during an episode of ketoacidosis.     

The behavioral management of chronic pain: Long-term follow-up with comparison groups

To assess the long-term efficacy of an operant inpatient treatment program for severely disabled chronic pain patients, 26 treated patients were compared with 20 rejected for treatment by a clinic team and 12 who refused treatment. At follow-up ranging from 1 to 8 years, 77% of treated participants were leading normal lives without medication for pain compared to one patient in the other two groups. At time of evaluation, unsuccessfully treated patients used more medications and were higher on MMPI measures of paranoia and lower on ego-strength than successfully treated patients. Spouses of unsuccessfully treated patients had higher MMPI scores on hypochondriasis and hysteria than spouses of successfully treated patients.     

Reduction of hyperornithinemia with a low protein,low arginine diet and pyridoxine in patients with a deficiency of ornithine-ketoacid transaminase (OKT) activity and gyrate atrophy of the choroid and retina

Five patients with gyrate atrophy of the choroid and retina showed a 60% or greater decline in plasma ornithine levels during a five week trial of a low protein (10–15 g/day), low arginine (0.50–0.75 g/day) diet supplemented with essential amino acids and pyridoxine administration. These declines in plasma ornithine levels were seen in Patients 1–4 with the pyridoxine non-responsive variant and in Patient 5 with the pyridoxine responsive variant. No harmful systemic side effects were noted. Patients 1–4 continued on a modified low protein (20–35 g/day), low arginine (1.25–1.75 g/day) diet as tolerated and Patient 5 on pyridoxine alone. After one year no improvement was observed in visual acuities, visual fields, final dark adapted thresholds and full field electroretinograms for four patients. In contrast to the other four patients, Patient 3, with relatively poor control of plasma ornithine levels, showed signs of progression of the chorioretinal atrophy and further reduction of electroretinographic responses. Patients 1–4 continue on the dietary regimen and Patient 5 on pyridoxine alone to determine whether any lowering of plasma ornithine levels will modify the course of their ocular disease.     

alpha-glucosidase activity in human leucocytes: choice of lymphocytes for the diagnosis of Pompe's disease and the carrier state.

alpha-Glucosidase activity was assayed in polymorphonuclear cells and lymphocytes from human peripheral blood with 4-methylumbelliferyl-alpha-D-glucopyranoside as substrate in the presence of sodium taurocholate. The pH vs. activity curve of the alpha-glucosidase indicated that differential estimation between acid and neutral alpha-glucosidases was difficult to perform with polymorphonuclear cells, but easily accessible with lymphocytes. The use of peripheral blood lymphocytes for the enzymatic diagnosis of Pompe's disease seemed to be more reliable than the use of whole leucocytes; this also the case with a classical Pompe's patient. The lymphocytes from the parents had normal or low normal activity of acid alpha-glucosidase in the freshly isolated state, but when cultured with phytohaemagglutinin for 72 h, the stimulated lymphocytes of both parents showed about half the enzyme activity of the cultured controls. It was deemed possible in all probability to identify the carrier state by assay of the enzyme activity in phytohaemagglutinin-stimulated lymphocytes.     

A new method for the determination of serum creatinine based on reaction with 3.5-dinitrobenzoyl chloride in an organic medium.

A new method for the determination of serum creatine, based on its reaction with 3,5-dinitrobenzoyl chloride in an organic medium is described. Various analytical parameters are studied and comparisons are made with the routine picrate procedures, as well as the dinitrobenzoic acid methods reported in the literature. On the basis of the data submitted, the proposed method is recommended for routine clinical use.     

Treatment of osteoarthritis of the knee with transcutaneous electrical nerve stimulation

Ten patients with pain due to osteoarthritis of the knee were treated in a double-blind cross-over study with two weeks of transcutaneous electrical nerve stimulation (TENS) and placebo. There was statistically significant pain relief by TENS and half of the patients chose to continue using TENS for pain control after the test month. However, at one year's follow-up, only two patients had sufficient benefit to continue using the device.     

Erum-induced changes in electrophoretic mobility of creatine phosphokinase isoenzymes?

BB isoenzyme of creatine phosphokinase (CK-BB) obtained from human brain-extract changes its electrophoretic mobility after incubation in human serum at 37° C. No change of electrophoretic mobility of CK-BB is observed after incubation in isotonic saline. We have shown by means of immunoprecipitation with specific antibodies that the structure of CK-BB is not changed. These findings are supported by other authors and make the diagnostic value of electrophoretic separation of CK isoenzymes doubtful as after a 3-h incubation CK-BB migrates similarly to CK-MB and consequently may be misinterpreted.     

Simple and rapid method for the diagnosis of chronic granulomatous disease, measuring hydrogen peroxide and superoxide anions released from leukocytes in whole blood.

A simple quantitative method to measure release of hydrogen peroxide and superoxide anions from leukocytes using less than 10 microliter blood is described. Whole blood instead of a leukocyte suspension was used. The release of hydrogen peroxide was measured fluorometrically by adding a blood sample to an assay mixture containing homovanillic acid, peroxidase and azide. The release of superoxide anions was measured spectrophotometrically with a dual wavelength spectrophotometer by adding a blood sample to an assay mixture containing cytochrome C. The normal values of the releasing activities are given.     

Plasma catecholamines and dopamine-beta-hydroxylase activity in chronic renal failure

Plasma and urinary catecholamines (CA) and plasma dopamine β-hydroxylase (DBH) activity were studied serially in 17 hypertensive patients with chronic renal failure (CRF) and in 15 age-matched patients with benign essential hypertension (EH). Resting levels of plasma epinephrine (E) plus norepinephrine (NE) in CRF patients were significantly greater than those in EH patients (P < 0.05), whereas plasma DBH activities in CRF patients tended to be lower than those in EH patients (P < 0.1). However, DBH activities were found to be similar for the two groups, when they were expressed in units per litre of blood instead of per litre of plasma. Urinary free E + NE and dopamine were significantly less in CRF than in EH, whereas no significant difference was noted in urinary excretion of conjugated E + NE and vanillylmandelic acid between the two groups. The ratio of conjugated E + NE/free E + NE and of vanillylmandelic acid/free E + NE were significantly greater in CRF than in EH patients (P < 0.05). Glomerular filtration rate correlated significantly with free E + NE, free and conjugated dopamine, and inversely with the ratio of conjugated E + NE/ free E + NE in the whole subjects. These findings suggest that raised plasma CA concentration associated with the relative enhancement of extraneuronal inactivations may be relevant to the retarded clearance of circulating CA rather than increased CA release in CRF patients. It is likely that many factors unrelated to sympathetic nerve discharge have a considerable influence on both plasma CA concentration and plasma DBH activity in CRF patients, making them unreliable for studying the role of sympathetic nerve activity in these patients.     

Living with chronic pain: the spouse's perspective

This report is part of a larger study mounted for purposes of investigating the effects on a family of chronic pain in one of its adult members. Data concerning the spouses' understanding of their mate's pain along with the spouses' perception of the impact of this problem on their own health are presented. The factors of uncertainty and helplessness were found to be central to the distress experienced by the spouses in this study. The finding that the experience of living with chronic pain extends beyond the individual sufferer to encompass the family as a whole would suggest that health professionals must incorporate the family into the process of learning the meaning and management of chronic pain.     

N-Acetyl-beta-D-glucosaminidase activity in normal and chronic lymphocytic leukaemic lymphocytes.

N-Acetyl-beta-D-glucosaminidase (EC 3.2.1.30) activity was measured fluorimetrically in: (a) lymphocytes from 20 normal donors, (b) enriched B and T lymphocyte populations prepared by E rosette sedimentation from 8 normal subjects, (c) lymphocytes from 15 untreated B cell chronic lymphocytic leukaemic patients. The pH profiles and optima (4.7) were similar in all preparations. Normal B lymphocytes had higher activity than normal T lymphocytes and both these preparations and normal unfractionated lymphocytes had significantly higher activity than chronic lymphocytic leukaemic lymphocytes. The apparent Michaelis constants were similar in normal unfractionated, B enriched and T enriched lymphocytes, whereas a reduced affinity for the enzyme was observed in the leukaemic lymphocytes. The difference in enzyme content between normal and chronic lymphocytic leukaemic lymphocytes cannot therefore be explained on the basis of a high B cell percentage in patients with chronic lymphocytic leukaemia.     

Serum vitamin E,lipid peroxide and glutathione peroxidase in patients with chronic pancreatitis

It has been reported that lipid peroxidation increases in patients with antioxidant deficiencies, such as vitamin E and glutathione peroxidase. The relationships between serum lipid peroxide and vitamin E on the one hand and glutathione peroxidase on the other were examined in 22 patients with chronic pancreatitis, often accompanied by malabsorption of fats and fat-soluble vitamins due to the impaired exocrine pancreatic function.Both serum vitamin E concentrations and glutathione peroxidase activities were depressed, especially in patients with chronic calcifying pancreatitis. On the other hand, serum lipid peroxide levels were elevated. A significant negative correlation was found between the serum lipid peroxide levels and vitamin E concentration.These findings suggest that an elevation of the serum lipid peroxide level may be due to the lack of an antioxidative defense mechanism, such as vitamin E, against lipid peroxide.     

Serum creatine kinase isoenzyme MB activity: Evaluation of a kit employing agarose-gel electrophoresis with overlay paper fluorescence scanning

A commercial kit for determining serum creatine kinase isoenzyme MB activity was evaluated. The kit employed agarose-gel electrophoresis followed by incubation of overlay paper on the agarose and then fluorescence scanning of the paper. Within-day coefficients of variation ranged from 24.9% for a specimen with no elevation of MB activity to 6.6% for a specimen with moderately elevated MB activity. The kit appeared to demonstrate MB in all sera and showed higher than expected values in recovery studies. The kit performed in a relatively linear fashion from 50 to 500 I.U./1 total creatine kinase activity. Hemolysis appeared to lower measured MB. For comparison with another method, specimens were also analyzed by microcolumn chromatography, which was found to incompletely separate isoenzymes. The kit produced lower values than microchromatography for specimens with low MB activities and higher values for specimens with elevated MB activities. Patients without corroborative evidence of myocardial injury showed a somewhat hyperbolic relationship between per cent MB and total creatine kinase activity, but MB activity was generally 4 I.U./1 or less. Although the kit had serious laboratory shortcomings, it may be as clinically useful as other methodologies.     

Carbonic anhydrase isoenzyme B in erythrocytes of subjects with chronic acidosis.

A specific and quantitative immunological method for determination of human erythrocyte carbonic anhydrase isoenzyme B has been used to ascertain the contents of this enzyme in the erythrocytes of healthy persons and of subjects with chronic metabolic and respiratory acidosis. The investigations have shown significant increase of carbonic anhydrase type B in the erythrocytes of patients suffering from renal failure with chronic acidosis, and in patients with chronic obstructive lung disease and chronic respiratory acidosis. The erythrocytes of acidotic uremic patients have a significantly higher content of erythrocyte carbonic anhydrase isoenzyme B than do the erythrocytes of uremic subjects without chronic acidosis. In chronic obstructive lung disease, the content of this enzyme in erythrocytes was significantly higher in the hypercapnic patients than in the normocapnic ones. In renal failure, significant correlation was found between carbonic anhydrase isoenzyme B and standard bicarbonate. In chronic obstructive lung disease no significant correlation was found between carbonic anhydrase and pCO2.     

Cholinesterase in serum and low density lipoprotein of hyperlipidemic patients.

Cholinesterase activity in the low density lipoprotein fraction of serum is increased in types IIa, IIb and IV hyperlipoproteinemic patients, whereas only types IIb and IV show increases in serum cholinesterase activity. In obese patients, cholinesterase activity is increased both in the serum and low density lipoprotein fraction only when hyperlipidemia is present. Cholinesterase activity is also found to increase in proportion with increases in low density lipoprotein, cholesterol, and triglycerides both in the serum and low density lipoprotein fraction. We suggest on the basis of these findings that cholinesterase has a function in lipid and lipoprotein metabolism.