Should an athlete eat straight after training?--A study of intestinal transit time and its relationship to prior exercise

The mouth-to-caecum transit time of food was measured using the rise in breath hydrogen after a standard breakfast of baked beans on two occasions in seven healthy volunteers. The first occasion was after resting and the second after moderate exercise on a bicycle ergometer. There was no significant difference between the transit times with or without prior exercise. It is concluded that moderate exercise taken before food does not interfere with transit time and therefore should not in that way interfere with nutrition.

Early identification and isolation of inpatients at high risk for tuberculosis

BACKGROUND

Although it has been recommended that all patients suspected of having tuberculosis be placed in isolation, the feasibility of this recommendation has not been investigated.

METHODS

Forty-three patients with pulmonary tuberculosis were compared with 43 control subjects. The control subjects had submitted expectorated sputum, and were culture negative. Variables included chest roentgenogram results, and risk factors used by the Centers for Disease Control and Prevention (Atlanta, Ga) to identify patients at increased risk for tuberculosis.

RESULTS

Potential control subjects outnumbered patients by 92:1. Although a positive tuberculin skin test, foreign birth, and weight loss were more common in the patients, 86% of the control subjects had at least one risk factor for tuberculosis. Chest roentgenograms consistent with tuberculosis (cavities or apical or nodular infiltrates) were found in 86% of the patients, but in only 16% of the control subjects (odds ratio, 31.7; 95% confidence interval, 8.6 to 127.7). The positive and negative predictive values of a consistent chest roentgenogram were 6% and 99.8%, respectively. The sensitivity of testing a single sputum specimen was 81%, yet almost half of the control subjects had only one specimen submitted. Of the inpatient cases, 58% were not identified on admission with a median delay of 13 days before isolation.

CONCLUSIONS

Isolating all the patients at the time sputum is submitted for testing is not practical and would have resulted in a 92-fold overuse of isolation rooms. The chest roentgenogram was of great value in identifying patients who did not require isolation and was the best available means of identifying inpatients at high risk for active pulmonary tuberculosis.

Sperm motility, morphology, hyperactivation, and ionophore-induced acrosome reactions after overnight incubation with mycoplasmas

OBJECTIVE

To evaluate the effect on the function on human sperm of overnight incubation with mycoplasma species.

DESIGN

Prospective controlled in vitro study.

SETTING

Community-based sperm bank and andrology laboratory.

INTERVENTIONS

Percoll-separated sperm were incubated overnight with a low densities of Myco-plasma hominis and Ureaplasma urealyticum serotypes.

MAIN OUTCOME MEASURES

Motility, midpiece and tail morphology, hyperactivation after overnight capacitation, and acrosome status after incubation with calcium ionophore.

RESULTS

Overnight incubation with mycoplasma species resulted in small but highly statistically significant differences in motility, morphology, hyperactivation after overnight capacitation, and proportion acrosome reacted after incubation with calcium ionophore compared with controls.

CONCLUSIONS

Incubation with mycoplasma species impairs sperm physiology. Identification and treatment of mycoplasma may augment a physiology-based infertility evaluation.

Behavioral counselling for subjects with acquired hearing loss. A new approach to hearing tactics

Effects of behavioral counselling of subjects with an acquired hearing loss were evaluated in an experimental design. The study included a group of 20 hearing-impaired subjects who were assessed and randomly allocated to a treatment or control group. Behavioural counselling, individualized according to the results of functional analysis, was then given to 10 subjects and included the teaching of 'hearing tactics'. The groups were measured three times, pre-counselling and post-counselling and at a 15-month follow-up, after which treatment results were analysed. Significant (time x treatment) interactions were followed by post-hoc testing revealing that the treated group had improved in several areas of functioning while controls had not. These results were in agreement with interview data. The findings indicate that a behavioural counselling approach to hearing tactics is beneficial in the understanding and rehabilitation of hearing loss, especially over time.

A behavioural approach to individually designed hearing tactics training

In an experimental study involving 20 subjects functional consequences of hearing disability were assessed and counselled in accordance with behavioural principles. The aims were to develop psychological methods for analysing and relieving hearing problems. The results indicated that treated subjects improved significantly in three functional areas as compared to controls. Subjects also developed more knowledge and ability to handle hearing problems than controls. Although these findings suggest that behavioural methods can be beneficial in the understanding and rehabilitation of handicaps related to hearing disability, they must be interpreted with caution given the small sample size.

Fungal symbionts of grasses: evolutionary insights and agricultural potential

Some filamentous fungal endophytes confer on their grass hosts important biological properties including resistance to grazing herbivores and resistance to nematodes and some fungal pathogens, as well as drought tolerance and greater field persistence. The production of alkaloids toxic to grazing animals is an undesirable aspect of the association in agronomic situations. Consequently, genetic strategies are being pursued to manipulate fungal endophytes and their hosts for agricultural benefit.

Antigen-presenting cells in adoptively transferred and spontaneous autoimmune diabetes

Histological techniques were used to identify antigen-presenting cells (APC) in adoptively transferred diabetes in NOD mice and Ins-HA transgenic mice, and in spontaneously diabetic NOD mice. In adoptively transferred disease, CD4+ T cells and F4/80+ macrophages dominated early infiltrates. By contrast, in spontaneously developing diabetes in NOD mice, lymphocytic infiltrates appeared to be well organized around a network of VCAM-1+ NLDC-145+ ICAM-1+ dendritic cells. Thus, the primary APC spontaneous autoimmune disease appears to be the strongly stimulatory dendritic cell rather than the normally resident macrophage. Next, we used chimeric animals to demonstrate that insulitis and diabetes could occur even when responding T cells were unable to recognize islet-specific antigen directly on beta cells. Altogether, the results demonstrate that immune-mediated damage does not require direct contact between CD4+ T cells and beta cells. Moreover, despite the induction of ICAM-1, VCAM-1, and class II on vascular endothelium near islet infiltrates, these experiments show that recruitment of lymphocytes occurs even when antigen presentation is not possible on vascular endothelium.

Perforation from endoscopic small bowel biopsy

Two patients, having undergone an apparently straightforward endoscopy with small bowel biopsy, developed a perforation. One, who proved to have normal small bowel mucosa, needed laparotomy and suturing of the duodenal perforation. The other, who had coeliac disease, settled with conservative management.

A recessive defect in lymphocyte or granulocyte function caused by an integrated transgene

A line of transgenic mice has been identified with a recessive defect in lymphocyte or granulocyte function, presumably as a result of insertional mutagenesis by the integrated transgene. Transgenic mice homozygous for the transgene integrant showed nearly complete absence of lymphocytes in peripheral lymph nodes and Peyer's patches, a severely diminished thymus medulla, and a greatly enlarged spleen. These animals also developed a syndrome characterized by granulocyte and mononuclear infiltrates in numerous tissues, including skin, liver, and lung, and immunoglobulin deposits in kidney glomeruli. Lung infiltrates were specifically localized around large blood vessels and bronchi, accompanied in some cases by destruction of arterial walls. The light scatter profile of spleen lymphocytes suggested an extremely high percentage of blast cells. Because tissue development and morphology appears to be normal in all other tissues observed, the genetic lesion appears to specifically affect the regulation of lymphocyte or granulocyte activation.

Synchronous squamous and glandular neoplasia of the anal canal

A 48 year old man presented with invasive adenocarcinoma in the wall of a non-healing anal fistula. The subsequent abdomino-perineal resection specimen showed residual invasive carcinoma coexisting with in situ carcinoma of anal glands as well as in situ squamous carcinoma of the anal canal. The epithelium of the anal canal had koilocytotic features. DNA hybridisation studies by the dot blot technique showed weak positivity for human papillomavirus (HPV) subtypes 16, 18. This case illustrates a number of important points--namely, anal fistulas, particularly non-healing fistulas should be biopsied to exclude malignancy; some adenocarcinomas of the anal arise in anal glands; the coexistence of glandular and squamous carcinoma with evidence of HPV infection is highly reminiscent of similar synchronous lesions of the uterine cervix and suggests that HPV may have an aetiological role in both squamous and glandular carcinomas of the anal canal.

Hemicellulose bioconversion to polyanionic heteropolysaccharides

Anionic polysaccharides, traditionally obtained from plant or algal sources, have a variety of commercial uses. Such gums from microorganisms have received increased recent interest. We have initiated a program to investigate the bioconversion of pentosans to rheologically useful anionic extracellular polysaccharides (AEPS). A number of earlier-described species, including Cryptococcus laurentii, Klebsiella pneumoniae, Arthrobacter viscosus, and Pseudomonas ATCC 31260, appear to have potential in this regard. These organisms can individually convert either xylose, enzymatic oligomeric hemicellulose digests, dilute mineral acid hemicellulose ("TVA") hydrolysates, or a five-monosaccharide mixture simulating sulfite process liquors to AEPS. The formation parameters, compositions, mol-wt distributions, and the intrinsic viscosities of these purified AEPS are exemplified. Substitution of pentose as the major substrate for glucose can result in changes in mol-wt distribution or in the percentage of noncarbohydrate substituents in some AEPS. Pursuit of these observations may lead to interesting structure-property relationships and toward rheological applications for pentosan-derived AEPS.

Casemix and costing hospital information program, Brisbane South Regional Health Authority: a preliminary study to determine the emergency department component of DRG costs

The issue of costs incurred for patients in the Emergency Department who are subsequently admitted was investigated by the authors to determine the significance of costs and to identify which DRGs and clinical specialties are likely to be affected. A theoretical costing study was performed in collaboration with the staff in the Emergency Department for patients admitted through this Department. The Study was a preliminary one with a number of methodological limitations. This paper describes how the costing exercise was performed. The DRGs most likely to be admitted via this route are identified and recommendations for further study are made. The study results identify a number of issues that require resolution prior to the introduction of casemix based funding.

Kinetics and efficacy of positive selection in the thymus of normal and T cell receptor transgenic mice

DNA-labeling studies in alpha beta T cell receptor (TCR) transgenic mice show that the lifespan of immature CD4+8+ thymocytes is 3.5 days irrespective of whether they are selected for maturation or not. While nonselected cells die, the binding of the TCR to thymic major histocompatibility complex molecules rescues CD4+8+ cells from programmed cell death and induces first upregulation of the TCR level and then differentiation into CD4+8- or CD4-8+ cells in the absence of any cell division. When most CD4+8+ thymocytes express a selectable transgenic TCR the formation of mature cells with high TCR levels is 10-20 times as efficient as observed in normal mice, yet still only 20% of the CD4+8+ cells become mature. This is due to the limited availability of selecting 'niches': most CD4+8+ thymocytes with a selectable transgenic TCR will undergo maturation when they represent only 5% or less of all CD4+8+ cells.

Trousseau's syndrome

Trousseau's syndrome remains a widely unrecognized and untreated complication of cancer. The clinical spectrum of the coagulopathy extends from uncomplicated superficial thrombophlebitis to life threatening DIC. Due to the absence of specific biochemical markers associated with the hypercoagulable state, this diagnosis is often overlooked. Initial intravenous heparin followed by the chronic administration of subcutaneous heparin will usually prevent thromboembolic recurrence.

Structure of an isoxazole amino ester

2'-(N-Methylamino)-2-methylpropyl 5-methyl-3-phenylisoxazole-4-carboxylate hydroiodide, C16H21N2O3+.I-, Mr = 416.26, orthorhombic, Pna21, a = 23.293 (7), b = 10.276 (3), c = 7.971 (1) A, V = 1908.0 (8) A3, Z = 4, Dx = 1.448 g cm-3, Mo K alpha, lambda = 0.71069 A, mu = 17.1 cm-1, F(000) = 832, T = 293 K, R = 0.0610 for 1846 unique observed reflections with F greater than 3 sigma. In the title compound, the isoxazole ring is distorted only slightly from planarity, with C(3) being 0.045 A out of the mean plane. Steric interactions force the isoxazole ring out of planarity with both the phenyl ring and the ester carbonyl O(2), which show dihedral angles of 34.9 (9) degrees and 47.2 (7) degrees, respectively. The N(2) amino methyl group is oriented approximately anti to the ester carbonyl O(2). The minimum iodide to nitrogen distance is from I to N(2)', 3.46 (2) A.

False aneurysm of the axillary artery following brachial plexus block

Brachial plexus blockade is a commonly used technique for providing surgical anesthesia for the upper extremity. Although various approaches have been described, the axillary approach is the safest and most frequently used. Most complications associated with axillary nerve block are related to local or systemic anesthetic toxicity, bleeding, infection, and nerve damage. A case of false aneurysm of the axillary artery following axillary nerve block is reported. The possible occurrence of this complication should be kept in mind to avoid permanent neurologic sequelae.

Surface expression of the beta T cell receptor (TCR) chain in the absence of other TCR or CD3 proteins on immature T cells

T cell receptor (TCR) beta genes are rearranged prior to TCR alpha genes. A productively rearranged TCR beta gene suppresses further V beta gene rearrangement. Here we show that in beta TCR transgenic mice the TCR beta-chain can be expressed on the surface of immature CD4-8- thymocytes, but not on mature T cells, in the absence of any other known TCR chain and proteins of the CD3 complex. Analysis by NEPHGE and SDS-PAGE showed that at least some beta TCR exists on the surface as a large disulfide-linked complex with unknown acidic molecules. The introduction of the beta TCR gene into scid mice resulted in the expression of the beta TCR on the cell surface of thymocytes and induced the expression of CD4 and CD8 co-receptors as well as transcription of the alpha TCR locus.

Ischaemic colitis as a complication of left-sided large bowel obstruction: a case report

Although obstructed left-sided colorectal cancer has traditionally been treated by a series of staged operations, there has been recent interest in the one-stage immediate resection technique. The case of a 72 year old woman who required 4 operations for obstructed left-sided colorectal cancer is presented.

Investigation and outcome of 121 infants and children requiring Nissen fundoplication for the management of gastroesophageal reflux

In a 6.5 year period starting January 1982, 121 patients (74 male, 47 female; 1.6:1) with complicated gastroesophageal reflux referred to Alberta Children's Hospital, University of Calgary, required a Nissen fundoplication at a mean age of 35.5 months (range 3 weeks to 18 years). The median age of onset of symptoms was less than 1 month. Symptoms and indications for surgery included regurgitation (88%), failure to thrive (52%), reflux-associated pulmonary symptoms and aspiration (48%), biopsy evidence of esophagitis (35%) with heartburn (17%), dysphagia (18%), hematemesis (17%), anemia (13%), and hypoproteinemia (22%). Sixty-four percent of the patients had a syndrome or chromosomal abnormality, respiratory disease, or neuromuscular disorder. The barium contrast upper-gastrointestinal radiographic series, performed in all patients, identified structural [gastric outlet obstruction (2%), esophageal stricture (11%), erosive esophagitis (9%)], and functional abnormalities [gastroesophageal reflux (90%), barium aspiration (8%), esophageal hypoperistalsis (30%), delayed gastric emptying (4%)]. Barium contrast upper gastrointestinal radiographic series identified gastroesophageal reflux with a sensitivity of 90% (compared to history), was 50% sensitive and 92% specific for erosive esophagitis (compared to biopsy), was 59% sensitive and 74% specific for esophageal dysmotility (compared to esophageal manometry), and there was a significant (p less than 0.01) association between barium aspiration and prior evidence of aspiration pneumonitis. Esophageal manometry demonstrated a significantly (p less than 0.001) lower esophageal sphincter pressure in patients compared with controls, but no significant correlation with failure to thrive, aspiration pneumonia, biopsy evidence of esophagitis, or parameters of the 24-hour esophageal pH study. Twenty-four hour pH monitoring showed significantly (p less than 0.05) more reflux episodes than in asymptomatic controls and there was significant (p less than 0.05) correlation between the percentage of time pH was less than 4 and the presence of hypoalbuminemia, and biopsy-proven erosive esophagitis or Barrett's esophagus. Endoscopic appearance was 91% sensitive and 60% specific for esophagitis when compared to biopsy. Nissen fundoplication was completely effective at resolving gastroesophageal reflux in 83%, and associated with marked improvement in 15%. No patient died as a result of fundoplication. Major complications included: recurrence of symptoms requiring reoperation (2%), subsequent mechanical bowel obstruction (8%), wound infection or pneumonia (12%).

Epidemic Norwegian scabies in a geriatric unit

Norwegian scabies is highly contagious and presents with a psoriasiform dermatosis. It afflicts particularly the elderly and patients with immunosuppression. Two weeks after the admission of an index case of Norwegian scabies to a geriatric ward, 13 and 25 patients and 6 of 18 ward nurses developed scabies. Despite comprehensive treatment, the ward epidemic recurred 6 weeks later probably as a result of inadequate treatment of the index case. This diagnosis should be considered when patients from high-risk groups present with an undiagnosed rash.

Predictors of tinnitus discomfort, adaptation and subjective loudness

In a nation-wide investigation, covering all the hearing centres in Sweden, a study was made of adaptation processes, subjective discomfort from tinnitus, subjective loudness of tinnitus and psychological complaints in 3372 subjects by means of a questionnaire. The most important predictors of discomfort from and adaptation to tinnitus were found to be the controllability and the degree of maskability by external sounds, i.e. the subject's coping abilities or internal-external locus of control. Increased control and masking effects from the environment imply a decrease in discomfort and better adaptation. The most important predictor of worsened subjective loudness of tinnitus was the duration of the tinnitus. That is, subjects who had had tinnitus for a longer time perceived the loudness as more intense. The psychosomatic factors which most strongly predicted increased discomfort from and decreased tolerance to tinnitus were depression and insomnia. These findings have theoretical and practical implications for the management and treatment of tinnitus.

Early deletion and late positive selection of T cells expressing a male-specific receptor in T-cell receptor transgenic mice

The ontogeny of T cells in T-cell receptor (TCR) transgenic mice, which express a transgenic alpha beta heterodimer, specific for the male (H-Y) antigen in association with H-2Db, was determined. The transgenic alpha chain was expressed on about 10% of the fetal thymocytes on day 14 of gestation. About 50% of day-15 fetal thymocytes expressed both alpha and beta transchains and virtually all fetal thymocytes expressed the transgenic alpha beta heterodimer by day 17. The early expression of the transgenic TCR on CD4-8- thymocytes prevented the development of gamma delta cells, and led to accelerated growth of thymocytes and an earlier expression of CD4 and CD8 molecules. Up to day 17, no significant differences in T-cell development could be detected between female and male thymuses. By day 18 of gestation, the male transgenic thymus contained more CD4-8- thymocytes than the female transgenic thymus. The preponderance of CD4-8- thymocytes in the male transgenic thymus increased until birth and was a consequence of the deletion of the CD4+8+ thymocytes and their CD4-8+ precursors. By the time of birth, the male transgenic thymus contained half the number of cells as the female transgenic thymus. The deletion of autospecific precursor cells in the male transgenic mouse began only at day 18 of gestation, despite the fact that the ligand could already be detected by day 16. The preferential accumulation of CD4-8+ T cells, which expressed a high density of the transgenic TCR, occurred only after birth and was obvious in 6-week-old female thymus. These data support the hypothesis that the positive selection of T cells expressing this transgenic heterodimer may involve two steps, i.e., the commitment of CD4+8+ thymocytes to the CD4-8+ lineage following the interaction of the transgenic TCR with restricting major histocompatibility molecules, followed by a slow conversion of CD4+8+ thymocytes into CD4-8+ T cells. In normal mice, the precursors of CD4+8+ and single positive thymocytes have the CD4-8- CD3-J11d+ (or M1/69+) phenotype. Because of the early expression of the transgenic alpha beta heterodimer, this population was not detected in adult transgenic mice. All CD4-8- M1/69+ cells expressed the transgenic receptor associated with CD3 and could be readily grown in media containing T-cell lectins and interleukin 2.

T-cell and plasma cell populations in coeliac small intestinal mucosa in relation to dermatitis herpetiformis

Differential lymphocyte and plasma cell counts and measurements of mucosal architecture were studied in small intestinal biopsies from 17 controls and 17 patients with untreated uncomplicated coeliac disease of whom five also had dermatitis herpetiformis. Intraepithelial T-cell and plasma cell counts and measurements of mucosal architecture were not significantly different in the two coeliac groups but both groups differed from the controls. Lamina propria T-cell counts were significantly higher in the patients who also had dermatitis herpetiformis than in uncomplicated coeliac disease, with a significant increase in the Leu 2 (CD8) positive (cytotoxic/suppressor) T-cell subset. This suggests a specific abnormality of T-cell control of immune responsiveness in the pathogenesis of the skin manifestations of dermatitis herpetiformis which is not found in uncomplicated coeliac disease.

Gastroenterology services: a regional review of changes over a five year period (1981-86)

A survey of all gastroenterologists in the Trent region showed that the number of upper GI endoscopies had doubled to 7.6 per 1000 of the population from 1981 to 1986, equalling the number of barium meals. Colonoscopies had increased from 0.39 to 0.94 per 1000 of the population. There had been a large increase in the proportion of endoscopies done by surgeons. There were 0.37 ERCP examinations per 1000 of the population done in six of the 12 districts, and 0.17 variceal sclerotherapy procedures per 1000 of the population done in five districts. There was widespread dissatisfaction with the provision of facilities and staff for endoscopy. From 1981 to 1986 the number of consultants with an interest in gastroenterology had increased from 20 to 25, but none of these appointments had been anticipated in 1981. All eight senior registrars in gastroenterology in 1981 had achieved consultant status - three in the region, four in the NHS outside the region, and one abroad.

The generation of mature T cells requires interaction of the alpha beta T-cell receptor with major histocompatibility antigens

THE T-cell repertoire within an individual is biased to recognize antigen in the context of self major histocompatibility complex (MHC) antigens. This is thought to depend on a process of positive selection during development. Support for this notion has recently been obtained in experiments using transgenic mice bearing genes for T-cell receptors (TCR) of defined specificity: T cells expressing the introduced genes form the main part of the mature T-cell population only in mice that express the appropriate MHC product. We have now extended these observations using TCR transgenic mice homozygous for the severe combined immunodeficiency (SCID) mutation which are defective in the rearrangement of both TCR and immunoglobulin genes. In this case mature thymocytes develop only in transgenic mice that express the MHC product which restricts the specificity of the transgenic TCR. This shows that the interaction of the alpha beta TCR with thymic MHC antigen is essential for the development of mature T cells. Furthermore, the peripheral lymph nodes of such mice are underdeveloped, suggesting that the peripheral expansion of mature T cells may require interactions with other lymphocytes expressing a range of receptors.

Dietary fat influences electric membrane properties of neurons in cell culture

1. SJL/J mice were maintained on semipurified diets which differed in the ratio of polyunsaturated/saturated fatty acid content (P/S). Exposure was from conception and was maintained for periods ranging from 6 to 34 weeks. 2. Neural cell cultures were prepared from dorsal root ganglia (DRG). After 6 and 20 days of culture, neuronal electric membrane properties were determined quantitatively by intracellular recording. 3. A number of significant differences were observed for the two dietary conditions. DRG from mice on the low-P/s diet had an increase in the rate of fall of both phases of repolarization which, in conjunction with the reduced action potential overshoot, led to a reduced action potential duration. This shift to shorter-duration action potentials was accompanied by a shift to more monophasic falling phases. The low-P/S neurons also exhibited a decreased afterhyperpolarization, decreased specific membrane resistance, and decreased membrane electrical time constant compared to high-P/S neurons. 4. It was concluded that the P/S ratio in the diet can have a significant effect on the electric properties of neurons. The high-P/S neurons tended to have action potentials with biphasic repolarizations and longer durations. In contrast, the low-P/S neurons tended to have action potentials with monophasic repolarizations and shorter durations. Moreover, the known ionic dependence of these two types of action potentials suggested that the low-P/S diet resulted in action potentials with a more exclusive Na dependence, while the high-P/S diet resulted in action potentials with both Na and Ca dependence.

Deletion of autospecific T cells in T cell receptor (TCR) transgenic mice spares cells with normal TCR levels and low levels of CD8 molecules

Transgenic mice that carry on a large fraction of their T cells an alpha/beta T cell receptor that recognizes the male antigen in the context of H-2Db molecules were constructed. An mAb specific for the transgenic receptor was developed and used to analyze T cell subsets in male transgenic H-2b mice. The vast majority of immature CD4+8+ T cells that express the transgenic TCR were deleted in the male transgenic mouse. Nevertheless, the majority of T cells spared by this deletion process expressed a high level of the transgenic TCR. These T cells, however, had an abnormal CD4/CD8 phenotype in that they expressed either no CD8 molecules or only low levels.

The psychological treatment of tinnitus: an experimental evaluation

Disabling tinnitus in 27 patients was treated in an experimental setting with two different type of therapy aiming at the development of coping behaviour. One was focused on behavioural control procedures, while the other aimed at more cognitive control methods such as distraction. The results of the two forms of therapy were compared with each other and with observations of the untreated control subjects. Assessments of subjective loudness, discomfort from tinnitus and controllability were made on analogue scales and at a questionnaire follow-up. Psychoacoustic measures such as personal loudness units (PLU) were used in connection with these self-recordings and for evaluation of treatment effects. The results confirmed favourable reports on behavioural methods in tinnitus. However, no differences were found between therapies. The results are discussed in the light of the coping and adaptation theory.

Behavioural therapy in the clinical management of tinnitus

Behavioural therapy was given to reduce discomfort and annoyance associated with severe tinnitus in 75 consecutive patients. Treatment was conducted within the routine clinical management. It included information and discussion about tinnitus, behavioural analysis and relaxation training combined with various cognitive strategies. The method of treatment was thus a form of coping technique. Self-recordings showed significant reductions of 'discomfort from tinnitus' as well as significant elevations in 'general mood' over a 3-month follow-up period. Interview findings indicated strong overall positive effects of treatment, as well as other positive side-effects on complaints such as tension headaches, dizziness, muscle tension and sleep disturbances. Implications for the clinical management of tinnitus sufferers are discussed.

Effects of aging on neuronal electrical membrane properties

The electric membrane properties (EMP) of dorsal root ganglion (DRG) neurons in cell cultures prepared from control mice (8-14 weeks) and old mice (90-92 weeks) were compared. The old neurons had a number of significant alterations in EMP compared to controls including decreased electrical excitability, increased action potential duration and more pronounced biphasicity of the repolarization phase. The old neurons also had larger action potential overshoot and afterhyperpolarization. The pattern of altered electric membrane properties was consistent with an age-induced shift from voltage-sensitive sodium channels to less excitable voltage-sensitive calcium channels and also a decrease in potassium permeability during the repolarizing phase of the action potential.