Estradiol- and progesterone-associated changes in microRNA-induced silencing and reduced anti-seizure efficacy of an antagomir in female mice

About one third of individuals living with epilepsy have treatment-resistant seizures. Alternative therapeutic strategies are thus urgently needed. One potential novel treatment target is microRNA-induced silencing, which is differentially regulated in epilepsy. Inhibitors (antagomirs) of specific microRNAs have shown therapeutic promise in preclinical epilepsy studies; however, these studies were mainly conducted in male rodent models, and research into microRNA regulation in females and by female hormones in epilepsy is scarce. This is problematic because female sex and the menstrual cycle can affect the disease course of epilepsy and may, therefore, also alter the efficacy of potential microRNA-targeted treatments. Here, we used the proconvulsant microRNA miR-324-5p and its target, the potassium channel Kv4.2, as an example to test how microRNA-induced silencing and the efficacy of antagomirs in epilepsy are altered in female mice. We showed that Kv4.2 protein is reduced after seizures in female mice similar to male mice; however, in contrast to male mice, microRNA-induced silencing of Kv4.2 is unchanged, and miR-324-5p activity, as measured by the association with the RNA-induced silencing complex, is reduced in females after seizure. Moreover, a miR-324-5p antagomir does not consistently reduce seizure frequency or increase Kv4.2 in female mice. As a possible underlying mechanism, we found that miR-324-5p activity and silencing of Kv4.2 in the brain were differentially correlated with plasma levels of 17β-estradiol and progesterone. Our results suggest that hormonal fluctuations in sexually mature female mice influence microRNA-induced silencing and could alter the efficacy of potential future microRNA-based treatments for epilepsy in females.Significance StatementMicroRNA-induced silencing is currently investigated in preclinical studies as a potential novel class of treatment target for epilepsy; however, surprisingly little is known about if and how microRNA-induced silencing is regulated by biological sex and if microRNA therapeutics are as effective in females as they are in males. This study shows that microRNA silencing of the potassium channel Kv4.2 and the functional activity of its targeting microRNA, miR-324-5p, change with plasma levels of estrogens and progesterone and that an inhibitor of miR-324-5p is less effective in female mice to suppress seizures. These findings are significant as they suggest microRNA-induced silencing as a novel molecular mechanism contributing to sex differences in epilepsy that could impact future therapy development.

Blocking substance P signaling reduces musculotendinous and dermal fibrosis and sensorimotor declines in a rat model of overuse injury

Purpose/Aim: Substance P-NK-1R signaling has been implicated in fibrotic tendinopathies and myositis. Blocking this signaling with a neurokinin 1 receptor antagonist (NK1RA) has been proposed as a therapeutic target for their treatment.Materials and Methods: Using a rodent model of overuse injury, we pharmacologically blocked Substance P using a specific NK1RA with the hopes of reducing forelimb tendon, muscle and dermal fibrogenic changes and associated pain-related behaviors. Young adult rats learned to pull at high force levels across a 5-week period, before performing a high repetition high force (HRHF) task for 3 weeks (2 h/day, 3 days/week). HRHF rats were untreated or treated in task weeks 2 and 3 with the NK1RA, i.p. Control rats received vehicle or NK1RA treatments.Results: Grip strength declined in untreated HRHF rats, and mechanical sensitivity and temperature aversion increased compared to controls; these changes were improved by NK1RA treatment (L-732,138). NK1RA treatment also reduced HRHF-induced thickening in flexor digitorum epitendons, and HRHF-induced increases of TGFbeta1, CCN2/CTGF, and collagen type 1 in flexor digitorum muscles. In the forepaw upper dermis, task-induced increases in collagen deposition were reduced by NK1RA treatment.Conclusions: Our findings indicate that Substance P plays a role in the development of fibrogenic responses and subsequent discomfort in forelimb tissues involved in performing a high demand repetitive forceful task.

Olfactory cell cultures to investigate health effects of air pollution exposure: Implications for neurodegeneration

Air pollution is a major, global public health concern. A growing body of evidence shows that exposure to air pollutants may impair the brain. Living in highly polluted areas has been linked to several neurodegenerative diseases, where exposure to complex mixtures of air pollutants in urban environments may have harmful effects on brain function. These harmful effects are thought to originate from elevated inflammation and oxidative stress. The olfactory epithelium is a key entry site of air pollutants into the brain as the particles are deposited in the upper airways and the nasal region. A potential source of patient-derived cells for study of air pollutant effects is the olfactory mucosa, which constitutes a central part of the olfactory epithelium. This review first summarizes the current literature on the available in vitro models of the olfactory epithelium. It then describes how alterations of the olfactory mucosa are linked to neurodegeneration and discusses potential therapeutic applications of these cells for neurodegenerative diseases. Finally, it reviews the research performed on the effects of air pollutant exposure in cells of the olfactory epithelium. Patient-derived olfactory epithelial models hold great promise for not only elucidating the molecular and cellular pathophysiology of neurodegenerative disorders, but for providing key understanding about air pollutant particle entry and effects at this key brain entry site.

A Pilot Study of Acupuncture for Tension Headache, Using a Novel Placebo

Tension headache is common, and treatment with acupuncture is frequently recommended, although the evidence of its effectiveness is contradictory. This small, randomised, controlled trial was designed as a pilot to test procedures in preparation for a multi-centre trial investigating the effect of acupuncture as a treatment for tension headache. Ten volunteers suffering from episodic, tension-type headache were recruited by local newspaper articles. Patients were randomised to receive either brief needling to tender areas or selected traditional points (Group A), or pressure from a cocktail stick supported within a guide tube to defined, non-tender and non-acupuncture areas (Group B). The patients’ view of the treatment sites was obstructed so that no indication could be gained as to which form of treatment was being given.

Throughout the period of the trial, duration, frequency and intensity of headaches were recorded, from which the mean weekly headache index was calculated. There was no difference between the changes in weekly headache index in the two groups, comparing scores before and after treatment. However, Group A experienced a considerably higher number of headache-free weeks than Group B. The credibility of the two procedures was tested using a standard credibility questionnaire and a “final verdict”. One subject in Group B concluded that she had not received genuine acupuncture, but overall there was no statistical difference between the credibility of treatment in the two groups.

Mitochondrial metals as a potential therapeutic target in neurodegeneration

Transition metals are critical for enzyme function and protein folding, but in excess can mediate neurotoxic oxidative processes. As mitochondria are particularly vulnerable to oxidative damage due to radicals generated during ATP production, mitochondrial biometal homeostasis must therefore be tightly controlled to safely harness the redox potential of metal enzyme cofactors. Dysregulation of metal functions is evident in numerous neurological disorders including Alzheimer's disease, stroke, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis and Friedrich's ataxia. This review describes the mitochondrial metal defects in these disorders and highlights novel metal-based therapeutic approaches that target mitochondrial metal homeostasis in neurological disorders.

X-ray fluorescence imaging reveals subcellular biometal disturbances in a childhood neurodegenerative disorder

Biometals such as zinc, iron, copper and calcium play key roles in diverse physiological processes in the brain, but can be toxic in excess. A hallmark of neurodegeneration is a failure of homeostatic mechanisms controlling the concentration and distribution of these elements, resulting in overload, deficiency or mislocalization. A major roadblock to understanding the impact of altered biometal homeostasis in neurodegenerative disease is the lack of rapid, specific and sensitive techniques capable of providing quantitative subcellular information on biometal homeostasis in situ. Recent advances in X-ray fluorescence detectors have provided an opportunity to rapidly measure biometal content at subcellular resolution in cell populations using X-ray Fluorescence Microscopy (XFM). We applied this approach to investigate subcellular biometal homeostasis in a cerebellar cell line isolated from a natural mouse model of a childhood neurodegenerative disorder, the CLN6 form of neuronal ceroid lipofuscinosis, commonly known as Batten disease. Despite no global changes to whole cell concentrations of zinc or calcium, XFM revealed significant subcellular mislocalization of these important biological second messengers in cerebellar Cln6nclf (CbCln6nclf ) cells. XFM revealed that nuclear-to-cytoplasmic trafficking of zinc was severely perturbed in diseased cells and the subcellular distribution of calcium was drastically altered in CbCln6nclf cells. Subtle differences in the zinc K-edge X-ray Absorption Near Edge Structure (XANES) spectra of control and CbCln6nclf cells suggested that impaired zinc homeostasis may be associated with an altered ligand set in CbCln6nclf cells. Importantly, a zinc-complex, ZnII(atsm), restored the nuclear-to-cytoplasmic zinc ratios in CbCln6nclf cells via nuclear zinc delivery, and restored the relationship between subcellular zinc and calcium levels to that observed in healthy control cells. ZnII(atsm) treatment also resulted in a reduction in the number of calcium-rich puncta observed in CbCln6nclf cells. This study highlights the complementarities of bulk and single cell analysis of metal content for understanding disease states. We demonstrate the utility and broad applicability of XFM for subcellular analysis of perturbed biometal metabolism and mechanism of action studies for novel therapeutics to target neurodegeneration.

Cellulose biogenesis: Polymerization and crystallization are coupled processes in Acetobacter xylinum

Calcofluor White ST, stilbene derivative used commerically as an optical brightener for cellulose, increased the rate of glucose polymerization into cellulose by resting cells of the gram-negative bacterium Acetobacter xylinum. This bacterium normally produces a ribbon of cellulose that is a composite of crystalline microfibrils. In concentrations above 0.1 mM, Calcofluor disrupts the assembly of crystalline cellulose I microfibrils and their integration into a composite ribbon by stoichiometric binding to glucose residues of newly polymerized glucan chains. Under these conditions, the rate of glucose polymerization increases up to 4 times the control rate, whereas oxygen uptake increases only 10-15%. These observed effects are readily reversible. If free Calcofluor is washed away or depleted below the threshold value by binding to cellulose as polymerization continues, ribbon production and the normal rate of polymerization resume. It is concluded that polymerization and crystallization are cell-directed, coupled processes and that the rate of crystallization determines the rate of polymerization. It is suggested that coupling must be maintained for biogenesis of crystalline cellulose I.

Enzymatic hydrolysis of cellulose: Visual characterization of the process

Cellulose from the Gram-negative bacterium Acetobacter xylinum has been used as a model substrate for visualizing the action of cellulase enzymes from the fungus Trichoderma reesei. High-resolution electron microscopy reveals that A. xylinum normally produces a ribbon of cellulose that is a composite of bundles of crystalline microfibrils. Visual patterns of the process of cellulose degradation have been established. Enzymes are initially observed bound to the cellulose ribbon. Within 10 min, the ribbon is split along its long axis into bundles of microfibrils which are subsequently thinned until they are completely dissolved within 30 min. Incubations with purified components of the cellulase enzyme system produced less dramatic changes in ribbon structure. Purified 1,4-beta-D-glucan cellobiohydrolase I (D) (EC 3.2.1.91) produced no visible change in cellulose structure. Purified endo-1,4-beta-D-glucanase IV (EC 3.2.1.4) produced some splaying of ribbons into microfibril bundles. In both cases, whole ribbons were present even after 60 min of incubation, visually confirming the synergistic mode of action of these enzymes.

Autogenic training for tension type headaches: A systematic review of controlled trials

OBJECTIVE

To determine from the published evidence whether autogenic training as sole therapy is effective for prevention of tension-type headaches in adults.

METHOD

Systematic review of controlled trials. Literature searches were performed in January 2005 in six major databases, specifically Medline, EMBASE, AMED, CENTRAL, PsychInfo and CINAHL and information was extracted and evaluated in a pre-defined manner.

RESULTS

Seven controlled clinical trials were included in the review. The methodological quality of these studies was low. Patient samples were generally representative of the more severely affected cases. None of the studies show autogenic training to be convincingly superior to other interventions care. Some trials suggested that the effect of autogenic training is no different from hypnosis and inferior to biofeedback.

CONCLUSION

There is no consistent evidence to suggest that autogenic training is superior to other interventions for prevention of tension headaches, or different from other forms of relaxation. Further studies should investigate the use of standard autogenic training in patients with moderate headache.

Arginase modulates myocardial contractility by a nitric oxide synthase 1-dependent mechanism

Cardiac myocytes contain two constitutive NO synthase (NOS) isoforms with distinct spatial locations, which allows for isoform-specific regulation. One regulatory mechanism for NOS is substrate (l-arginine) bioavailability. We tested the hypothesis that arginase (Arg), which metabolizes l-arginine, constrains NOS activity in the cardiac myocyte in an isoform-specific manner. Arg activity was detected in both rat heart homogenates and isolated myocytes. Although both Arg I and II mRNA and protein were present in whole heart, Arg II alone was found in isolated myocytes. Arg inhibition with S-(2-boronoethyl)-l-cysteine (BEC) augmented Ca(2+)-dependent NOS activity and NO production in myocytes, which did not depend on extracellular l-arginine. Arg II coimmunoprecipited with NOS1 but not NOS3. Isolation of myocyte mitochondrial fractions in combination with immuno-electron microscopy demonstrates that Arg II is confined primarily to the mitochondria. Because NOS1 positively modulates myocardial contractility, we determined whether Arg inhibition would increase basal myocardial contractility. Consistent with our hypothesis, Arg inhibition increased basal contractility in isolated myocytes by a NOS-dependent mechanism. Both the Arg inhibitors N-hydroxy-nor-l-arginine and BEC dose-dependently increased basal contractility in rat myocytes, which was inhibited by both nonspecific and NOS1-specific NOS inhibitors N(G)-nitro-l-arginine methyl ester and S-methyl-l-thiocitrulline, respectively. Also, BEC increased contractility in isolated myocytes from WT and NOS3 but not NOS1 knockout mice. We conclude that mitochondrial Arg II negatively regulates NOS1 activity, most likely by limiting substrate availability in its microdomain. These findings have implications for therapy in pathophysiologic states such as aging and heart failure in which myocardial NO signaling is disrupted.

Acupuncture and related interventions for smoking cessation

BACKGROUND

Acupuncture and related techniques are promoted as a treatment for smoking cessation in the belief that they may reduce nicotine withdrawal symptoms.

OBJECTIVES

The objectives of this review are to determine the effectiveness of acupuncture and the related interventions of acupressure, laser therapy and electrostimulation, in smoking cessation in comparison with no intervention, sham treatment, or other interventions.

SEARCH STRATEGY

We searched the Cochrane Tobacco Addiction Group specialized register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, BIOSIS Previews, PsycINFO, Science and Social Sciences Citation Index, AMED and CISCOM. Date of last search January 2005.

SELECTION CRITERIA

Randomized trials comparing a form of acupuncture, acupressure, laser therapy or electrostimulation with either no intervention, sham treatment or another intervention for smoking cessation.

DATA COLLECTION AND ANALYSIS

We extracted data in duplicate on the type of smokers recruited, the nature of the acupuncture and control procedures, the outcome measures, method of randomization, and completeness of follow up. We assessed abstinence from smoking at the earliest time-point (before six weeks), and at the last measurement point between six months and one year. We used the most rigorous definition of abstinence for each trial, and biochemically validated rates if available. Those lost to follow up were counted as continuing smokers. Where appropriate, we performed meta-analysis using a fixed-effect model.

MAIN RESULTS

We identified 24 reports of studies. The only comparison for which there were sufficient studies to combine meaningfully was acupuncture compared with sham acupuncture. The fixed-effect odds ratio (OR) for the short-term effect was 1.36 (95% confidence interval 1.07 to 1.72), but the studies are heterogeneous and the result is strongly influenced by one individual positive study. The significant short-term effect was lost with the random-effects model for pooling, or by removing the outlying study that led to heterogeneity. The long-term result shows no effect of acupuncture compared with sham acupuncture. There was no consistent evidence that acupuncture is superior to no treatment, and no evidence that the effect of acupuncture was different from that of other anti-smoking interventions, or that any particular acupuncture technique is superior to other techniques.

AUTHORS' CONCLUSIONS

There is no consistent evidence that acupuncture, acupressure, laser therapy or electrostimulation are effective for smoking cessation, but methodological problems mean that no firm conclusions can be drawn. Further research using frequent or continuous stimulation is justified.

The Evolution of Oscillatory Behavior in Age‐Structured Species

A major challenge in ecology is to explain why so many species show oscillatory population dynamics and why the oscillations commonly occur with particular periods. The background environment, through noise or seasonality, is one possible driver of these oscillations, as are the components of the trophic web with which the species interacts. However, the oscillation may also be intrinsic, generated by density-dependent effects on the life history. Models of structured single-species systems indicate that a much broader range of oscillatory behavior than that seen in nature is theoretically possible. We test the hypothesis that it is selection that acts to constrain the range of periods. We analyze a nonlinear single-species matrix model with density dependence affecting reproduction and with trade-offs between reproduction and survival. We show that the evolutionarily stable state is oscillatory and has a period roughly twice the time to maturation, in line with observed patterns of periodicity. The robustness of this result to variations in trade-off function and density dependence is tested.

Enhanced Vasodilatory Responses to Milrinone in Catecholamine-Precontracted Small Pulmonary Arteries

Beta-adrenergic agonists (e.g., epinephrine [E] and norepinephrine [NE]) and phosphodiesterase-III inhibitors (e.g., milrinone) are often used in combination to augment ventricular function in the perioperative period. In the myocardium, milrinone acts synergistically with beta-adrenergic agonists to increase contractility. However, the potential interaction between catecholamines with combined alpha- and beta-adrenergic activity and milrinone in the pulmonary circulation has not been determined. We evaluated the vasodilatory effects of milrinone and nitroglycerine on large elastic and small muscular porcine pulmonary vascular rings precontracted with catecholamines with beta-adrenergic agonist activity (E and NE), the alpha-adrenergic agonist phenylephrine, and a nonadrenergic agonist, the thromboxane analog U46619. In small pulmonary arteries, the vasorelaxation with milrinone was significantly enhanced in rings precontracted with E or NE compared with those precontracted with phenylephrine or U46619. However, in large pulmonary arteries, the vasorelaxation with milrinone was similar in all vessel rings and was not influenced by the agonist used to induce precontraction. In marked contrast, the vasorelaxant responses to nitroglycerine were not altered by the specific agonist used for precontraction in either small or large pulmonary vascular rings. Thus, the pulmonary vascular effects of milrinone are enhanced when combined with drugs with beta-adrenoreceptor agonist activity. The vasodilatory interactions exhibited by phosphodiesterase-III inhibitors and the catecholamines NE and E suggest that their combined use might be beneficial in circumstances in which ventricular dysfunction and increased pulmonary vascular resistance occur.

IMPLICATIONS

This study demonstrated that milrinone had enhanced vasodilator effects when combined with drugs with beta-adrenoreceptor agonist activity in small pulmonary artery segments removed from pigs.

Autogenic training reduces anxiety after coronary angioplasty: a randomized clinical trial

OBJECTIVES

Autogenic training (AT) is a method of autosuggestion with some potential for reducing anxiety. This study tests whether AT lowers anxiety levels experienced by patients undergoing coronary angioplasty.

METHODS

Fifty-nine patients were randomly assigned to receive regular AT or no such therapy as an adjunct to standard care for 5 months. The primary outcome measure was State Anxiety at 2 months. Qualitative information was generated by face-to-face interviews.

RESULTS

State Anxiety showed a significant intergroup difference both at 2 and 5 months. This finding was corroborated by secondary outcome measures, for example, quality of life, and by qualitative information about patients' experiences. The results do not allow us to determine whether the observed effects are specific to AT or of a nonspecific nature.

CONCLUSIONS

Our results suggest that AT may have a role in reducing anxiety of patients undergoing coronary angioplasty.

Evidence for a possible role for nitric oxide in the modulation of heart activity in Achatina fulica and Helix aspersa

The effects of nitric oxide (NO) donors, S-nitroso-N-acetylpenicillamine, S-nitroso-l-glutathione, sodium nitroprusside and sodium nitrite were investigated on the activity of the isolated hearts of Achatina fulica and Helix aspersa. NO donors inhibited heart activity in a concentration-dependent manner. The only exception was sodium nitroprusside, which excited H. aspersa heart. The inhibitory effects of these NO donors were reduced by the NO scavenger, methylene blue, the guanylyl cyclase inhibitor, 1H-(1,2,4) Oxadiazolo(4,3-a)quinoxalin-1-one (ODQ), and potentiated by 8-Br-cGMP and the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX). Acetylcholine also inhibited the heart activity, and this inhibition was reduced by methylene blue and ODQ. Positive NADPH-diaphorase staining was located in the outer pericardial layer of the heart of A. fulica. The present results provide evidence that NO may modulate the activity of gastropod hearts, and this modulation may modify the inhibitory action of acetylcholine on heart activity.

A review of controlled trials of acupuncture for women's reproductive health care

BACKGROUND

Acupuncture as a therapy, and acupressure as self-treatment, are increasingly widely used for gynaecological conditions, and this study aims to review the scientific literature on their effectiveness.

METHOD

A systematic review of controlled trials of acupuncture or acupressure for gynaecological conditions, published in a European language.

SYNTHESIS

No studies in mastalgia, menorrhagia, pelvic pain, premenstrual syndrome or vulvodynia met the inclusion criteria. Four studies, two of which were patient-blinded, of acupuncture or acupressure for dysmenorrhoea suggest that it may have an effect. Three studies of acupuncture given at various stages of infertility treatment are promising, but none was patient-blind. Two studies of acupuncture for menopausal symptoms showed no effect during the treatment period when compared with sham acupuncture, and a third study showed no effect on hypertension in postmenopausal women, though some improvement in symptoms was noted.

CONCLUSION

In view of the small number of studies and their variable quality, doubt remains about the effectiveness of acupuncture for gynaecological conditions. Acupuncture and acupressure appear promising for dysmenorrhoea, and acupuncture for infertility, and further studies are justified.

Validating a New Sham (Placebo) Acupuncture Device: Two Randomized Controlled Trials

Background

For clinical trials of acupuncture, it would be desirable to have a sham procedure that is indistinguishable from the real treatment, yet inactive. A sham needle has been designed which telescopes instead of penetrating the skin. The Park Sham Device involves an improved method of supporting the sham needle and requires validation.

Objective

To test whether the sham procedure using the new device is: 1. Indistinguishable from real needles, and 2. Inactive.

Design

Two subject and assessor-blind, randomized controlled trials. Study samples: Study 1: 58 patients included in a clinical trial of acupuncture for acute stroke. Study 2: 63 healthy, acupuncture naïve, adult volunteers. Intervention: Real or sham acupuncture using the Park Sham Device. Settings: 1. District general hospital, 2. University laboratory. Measurements: 1. The form of treatment that patients believed they had received 2. Experience of de-qi, as judged by three acupuncture experts.

Results

Study 1: No patient in either group believed s/he had been treated with the sham needle. Study 2: In 40 volunteers for whom experts achieved consensus, the relative risk of experiencing de-qi with real acupuncture to that with sham acupuncture was 15.38 (95% CI 2.26 to 104.86). The inter-rater reliability of all 13 experts, calculated from their judgements on 10 subjects selected by randomisation, was 0.52 (95% CI 0.19 to 0.61).

Conclusions

Results suggest that the procedure using the new Park Sham Device is both indistinguishable from real acupuncture and inactive. It is therefore a valid control for acupuncture trials. The findings also lend support to the existence of de-qi, a major concept underlying traditional Chinese acupuncture.

[Acupuncture for back pain: meta-analysis of randomised controlled trials and an update with data from the most recent studies]

BACKGROUND

Acupuncture is commonly used to treat back pain. A meta-analysis of clinical trials of acupuncture for this condition came to a positive conclusion whilst a qualitative review was negative.

AIM

To compare our meta-analysis of trials of acupuncture for the treatment of back pain with a qualitative review and the most recent studies on the subject.

METHODS

A systematic literature search was conducted to retrieve all randomised controlled trials of any form of acupuncture for any type of back pain in humans. The adequacy of the acupuncture was assessed by consulting six experienced acupuncturists. The main outcome measure for the meta-analysis was numbers of subjects who where improved at the end of treatment. These data are discussed in relation to the qualitative review and the most recent studies.

RESULTS

Twelve studies were included of which nine presented data suitable for meta-analysis. The odds ratio of improvement with acupuncture compared with control intervention was 2.30 (95% confidence interval 1.28 to 4.13). For sham-controlled, evaluator-blinded studies, the odds ratio was 1.37 (95% confidence interval, 0.84-2.25). The results from the majority of the most recent studies also support the effectiveness of acupuncture in the treatment of back pain.

CONCLUSIONS

Collectively, these data imply that acupuncture is superior to various control interventions, although there is insufficient evidence to state whether it is superior to placebo.

Relaxation therapies for asthma: a systematic review

BACKGROUND

Emotional stress can either precipitate or exacerbate both acute and chronic asthma. There is a large body of literature available on the use of relaxation techniques for the treatment of asthma symptoms. The aim of this systematic review was to determine if there is any evidence for or against the clinical efficacy of such interventions.

METHODS

Four independent literature searches were performed on Medline, Cochrane Library, CISCOM, and Embase. Only randomised clinical trials (RCTs) were included. There were no restrictions on the language of publication. The data from trials that statistically compared the treatment group with that of the control were extracted in a standardised predefined manner and assessed critically by two independent reviewers.

RESULTS

Fifteen trials were identified, of which nine compared the treatment group with the control group appropriately. Five RCTs tested progressive muscle relaxation or mental and muscular relaxation, two of which showed significant effects of therapy. One RCT investigating hypnotherapy, one of autogenic training, and two of biofeedback techniques revealed no therapeutic effects. Overall, the methodological quality of the studies was poor.

CONCLUSIONS

There is a lack of evidence for the efficacy of relaxation therapies in the management of asthma. This deficiency is due to the poor methodology of the studies as well as the inherent problems of conducting such trials. There is some evidence that muscular relaxation improves lung function of patients with asthma but no evidence for any other relaxation technique.

Acupuncture for smoking cessation

BACKGROUND

Acupuncture and related techniques are promoted as a treatment for smoking cessation in the belief that they may reduce nicotine withdrawal symptoms.

OBJECTIVES

The objective of this review is to determine the effectiveness of acupuncture and the allied therapies of acupressure, laser therapy and electrostimulation, in smoking cessation in comparison with: a) sham treatment, b) other interventions, or c) no intervention.

SEARCH STRATEGY

We searched the Cochrane Tobacco Addiction Group trials register, Cochrane Controlled Trials Register, Medline, Embase, BIOSIS Previews, PsycINFO, Science and Social Sciences Citation Index, AMED and CISCOM. Date of last search January 2002.

SELECTION CRITERIA

Randomised trials comparing a form of acupuncture, acupressure, laser therapy or electrostimulation with either sham treatment, another intervention or no intervention for smoking cessation.

DATA COLLECTION AND ANALYSIS

We extracted data in duplicate on the type of smokers recruited, the nature of the acupuncture and control procedures, the outcome measures, method of randomisation, and completeness of follow-up. We assessed abstinence from smoking at the earliest time-point (before 6 weeks), at six months and at one year or more follow-up in patients smoking at baseline. We used the most rigorous definition of abstinence for each trial, and biochemically validated rates if available. Those lost to follow-up were counted as continuing to smoke. Where appropriate, we performed meta-analysis using a fixed effects model.

MAIN RESULTS

We identified 22 studies. Acupuncture was not superior to sham acupuncture in smoking cessation at any time point. The odds ratio (OR) for early outcomes was 1.22 (95% confidence interval 0.99 to 1.49); the OR after 6 months was 1.50 (95% confidence interval 0.99 to 2.27) and after 12 months 1.08 (95% confidence interval 0.77 to 1.52). Similarly, when acupuncture was compared with other anti-smoking interventions, there were no differences in outcome at any time point. Acupuncture appeared to be superior to no intervention in the early results, but this difference was not sustained. The results with different acupuncture techniques do not show any one particular method (i.e. auricular acupuncture or non-auricular acupuncture) to be superior to control intervention. Based on the results of single studies, acupressure was found to be superior to advice; laser therapy and electrostimulation were not superior to sham forms of these therapies.

REVIEWER'S CONCLUSIONS

There is no clear evidence that acupuncture, acupressure, laser therapy or electrostimulation are effective for smoking cessation.

Clinical trials of acupuncture: consensus recommendations for optimal treatment, sham controls and blinding

Evidence of effectiveness is increasingly used to determine which health technologies are incorporated into public health provision. Acupuncture is a popular therapy that has been shown to be superior to placebo in the treatment of nausea and dental pain, and promising for migraine and osteoarthritis of the knee. For many other conditions, such as chronic pain, in which acupuncture is often used, the evidence is either insufficient or negative. Misleading results may occur for a number of reasons. False negative results may arise from inadequate treatment schedules and inappropriate control interventions. This consensus document considers these issues with the aim of improving the design of efficacy trials of acupuncture in order that they are more likely to be conclusive and more meaningfully interpreted. Clinical trials of acupuncture must use an optimal form of treatment; this can be defined by examining standard texts, by surveying and consulting experts. There are a great many variables in treatment (such as point selection, form of stimulation) all of which need to be addressed in designing and reporting clinical trials. The control procedure is determined by the precise research question that is being addressed. For efficacy studies, in which the question is whether acupuncture has specific effects (i.e. is superior to placebo), sham forms of acupuncture appear the most appropriate method of controlling for needle penetration. A recent development of blunted, telescopic needles may represent a major advance. Such procedures may produce a therapeutic response so should preferably be recorded as 'sham' procedures rather than true 'placebo' controls. Blinding in clinical trials is an accepted means of reducing bias. Patient blinding in acupuncture studies can be achieved by sham procedures and its success should be measured. While practitioner blinding is difficult, though not impossible, blinding of the observer and the analyst should be considered as the ideal for all studies. A number of recommendations are made which aim to improve the quality of sham-controlled acupuncture studies.

Cue dependency of nicotine self-administration and smoking

A paradox exists regarding the reinforcing properties of nicotine. The abuse liability associated with smoking equals or exceeds that of other addictive drugs, yet the euphoric, reinforcing and other psychological effects of nicotine, compared to these other drugs, are more subtle, are manifest under more restricted conditions, and do not readily predict the difficulty most smokers experience in achieving abstinence. One possible resolution to this apparent inconsistency is that environmental cues associated with drug delivery become conditioned reinforcers and take on powerful incentive properties that are critically important for sustaining smoking in humans and nicotine self-administration in animals. We tested this hypothesis by using a widely employed self-administration paradigm in which rats press a lever at high rates for 1 h/day to obtain intravenous infusions of nicotine that are paired with two types of visual stimuli: a chamber light that when turned on signals drug availability and a 1-s cue light that signals drug delivery. We show that these visual cues are at least as important as nicotine in sustaining a high rate of responding once self-administration has been established, in the degree to which withdrawing nicotine extinguishes the behavior, and in the reinstatement of lever pressing after extinction. Additional studies demonstrated that the importance of these cues was manifest under both fixed ratio and progressive ratio (PR) schedules of reinforcement. The possibility that nicotine-paired cues are as important as nicotine in smoking behavior should refocus our attention on the psychology and neurobiology of conditioned reinforcers in order to stimulate the development of more effective treatment programs for smoking cessation.

Involvement of the 5-lipoxygenase pathway in the neurotoxicity of the prion peptide PrP106-126

Transmissible spongiform encephalopathies are characterised by the transformation of the normal cellular prion protein (PrP(C)) into an abnormal isoform (PrP(TSE)). Previous studies have shown that N-methyl-D-aspartate (NMDA) receptor antagonists can inhibit glutathione depletion and neurotoxicity induced by PrP(TSE) and a toxic prion protein peptide, PrP106-126, in vitro. NMDA receptor activation is known to increase intracellular accumulation of Ca(2+), resulting in up-regulation of arachidonic acid (AA) metabolism. This can stimulate the lipoxygenase pathways that may generate a number of potentially neurotoxic metabolites. Because of the putative relationship between AA breakdown and PrP106-126 neurotoxicity, we investigated AA metabolism in primary cerebellar granule neuron cultures treated with PrP106-126. Our studies revealed that PrP106-126 exposure for 30 min significantly up-regulated AA release from cerebellar granule neurons. PrP106-126 neurotoxicity was mediated through the 5-lipoxygenase (5-LOX) pathway, as shown by abrogation of neuronal death with the 5-LOX inhibitors quinacrine, nordihydroguaiaretic acid, and caffeic acid. These inhibitors also prevented PrP106-126-induced caspase 3 activation and annexin V binding, indicating a central role for the 5-LOX pathway in PrP106-126-mediated proapoptosis. Interestingly, inhibitors of the 12-lipoxygenase pathway had no effect on PrP106-126 neurotoxicity or proapoptosis. These studies clearly demonstrate that AA metabolism through the 5-LOX pathway is an important early event in PrP106-126 neurotoxicity and consequently may have a critical role in PrP(TSE)-mediated cell loss in vivo. If this is so, therapeutic intervention with 5-LOX inhibitors may prove beneficial in the treatment of prion disorders.

Copper and zinc binding modulates the aggregation and neurotoxic properties of the prion peptide PrP106-126

The abnormal form of the prion protein (PrP) is believed to be responsible for the transmissible spongiform encephalopathies. A peptide encompassing residues 106-126 of human PrP (PrP106-126) is neurotoxic in vitro due its adoption of an amyloidogenic fibril structure. The Alzheimer's disease amyloid beta peptide (Abeta) also undergoes fibrillogenesis to become neurotoxic. Abeta aggregation and toxicity is highly sensitive to copper, zinc, or iron ions. We show that PrP106-126 aggregation, as assessed by turbidometry, is abolished in Chelex-100-treated buffer. ICP-MS analysis showed that the Chelex-100 treatment had reduced Cu(2+) and Zn(2+) levels approximately 3-fold. Restoring Cu(2+) and Zn(2+) to their original levels restored aggregation. Circular dichroism showed that the Chelex-100 treatment reduced the aggregated beta-sheet content of the peptide. Electron paramagnetic resonance spectroscopy identified a 2N1S1O coordination to the Cu(2+) atom, suggesting histidine 111 and methionine 109 or 112 are involved. Nuclear magnetic resonance confirmed Cu(2+) and Zn(2+) binding to His-111 and weaker binding to Met-112. An N-terminally acetylated PrP106-126 peptide did not bind Cu(2+), implicating the free amino group in metal binding. Mutagenesis of either His-111, Met-109, or Met-112 abolished PrP106-126 neurotoxicity and its ability to form fibrils. Therefore, Cu(2+) and/or Zn(2+) binding is critical for PrP106-126 aggregation and neurotoxicity.

Effectiveness of acupuncture for stroke: a systematic review

BACKGROUND

Acupuncture has been suggested as a treatment for stroke rehabilitation, but the question whether it is effective has not been answered satisfactorily.

PURPOSE

To summarise and critically review all randomised controlled trials of the effectiveness of acupuncture as a treatment for stroke.

METHODS

Four independent computerised literature searches (in MEDLINE, Cochrane Controlled Trials Register, Embase, and CISCOM data bases) were conducted in June 1999. All randomised-controlled trials that compared any form of needle insertion acupuncture to any form of non-acupuncture control intervention in the treatment of human stroke patients were included. Data were extracted independently by two authors and arbitrated by a third. The methodological quality of the included studies was assessed using the Jadad score.

RESULTS

Nine randomised controlled trials with a total sample size of 538 patients were included. Two studies were assessor blind, one was subject blind, and one was assessor and subject blind. Two studies exclusively used manual acupuncture, five only electroacupuncture, and two used both. Outcome measures used were Scandinavian Stroke Scale, Chinese Stroke Scale or Recovery Scale, Barthel index, Nottingham Health Profile, Motor function, balance, and days in hospital. Of the nine studies, six yielded a positive result suggesting that acupuncture is effective, and three produced a negative finding implying that acupuncture is not superior to control treatment. Only two studies obtained a Jadad score of more than 3. These methodologically best trials showed no significant effect of acupuncture.

CONCLUSION

Based on the evidence of rigorous randomised controlled trials, there is no compelling evidence to show that acupuncture is effective in stroke rehabilitation. Further, better-designed studies are warranted.

Needling therapies in the management of myofascial trigger point pain: a systematic review

OBJECTIVE

To establish whether there is evidence for or against the efficacy of needling as a treatment approach for myofascial trigger point pain.

DATA SOURCES

PubMed, Ovid MEDLINE, Ovid EMBASE, the Cochrane Library, AMED, and CISCOM databases, searched from inception to July 999.

STUDY SELECTION

Randomized, controlled trials in which some form of needling therapy was used to treat myofascial pain.

DATA EXTRACTION

Two reviewers independently extracted data concerning trial methods, quality, and outcomes.

DATA SYNTHESIS

Twenty-three papers were included. No trials were of sufficient quality or design to test the efficacy of any needling technique beyond placebo in the treatment of myofascial pain. Eight of the 10 trials comparing injection of different substances and all 7 higher quality trials found that the effect was independent of the injected substance. All 3 trials that compared dry needling with injection found no difference in effect.

CONCLUSIONS

Direct needling of myofascial trigger points appears to be an effective treatment, but the hypothesis that needling therapies have efficacy beyond placebo is neither supported nor refuted by the evidence from clinical trials. Any effect of these therapies is likely because of the needle or placebo rather than the injection of either saline or active drug. Controlled trials are needed to investigate whether needling has an effect beyond placebo on myofascial trigger point pain.

Systematic review of adverse events following acupuncture: the Japanese literature

CONTEXT

Many Japanese cases of adverse events after acupuncture are not listed in medical databases such as Medline. Therefore, they are not easily accessible to researchers outside Japan.

OBJECTIVE

To complement existing reviews of adverse events after acupuncture in the West and to provide more detailed discussion and analysis.

DATA SOURCES

Literature search using 'Igaku Chuo Zasshi (Japana Centra Revuo Medicina) CD-ROM version' covering the period of 1987-1999.

STUDY SELECTION

Case reports of adverse events, which were suspected to be due to acupuncture treatment, were included. Experimental studies, surveys, and news articles were excluded.

DATA EXTRACTION

Two independent reviewers extracted data from located articles in a pre-defined structured way, and assessed likelihood of causality in each individual case.

DATA SYNTHESIS

89 articles which reported 124 cases were located. The most frequent adverse events were: pneumothorax (25 cases), spinal cord injury (18 cases), acute hepatitis B (11 cases), and localized argyria (10 cases). There were two fatalities from infections. Forty-eight events were caused by needle breakage including 26 cases of intentionally embedded needle and 16 cases of accidental breakage. There were also 10 cases of injury from self-treatment.

CONCLUSION

Although it has already been demonstrated that severe adverse events seem to be uncommon in standard practice, many serious cases of negligence have been found in the present review, suggesting that training system for acupuncturists (including medical doctors) should be improved and that unsupervised self-treatment should be discouraged.

Prospective studies of the safety of acupuncture: a systematic review

PURPOSE

The objective of this review was to determine the incidence of adverse events associated with acupuncture.

SUBJECTS AND METHODS

A search for prospective surveys of the safety of acupuncture was conducted using computerized databases (Medline, Embase, the Cochrane Library, and CISCOM), inquiries to acupuncture organizations, and our own files. Data on sample, size, types of patients duration of study, types of acupuncture, definition of adverse events, method of evaluation, and findings were extracted systematically from the retrieved reports.

RESULTS

Nine surveys were located and included in the review. Their results were not uniform. The most common adverse events were needle pain (1% to 45%) from treatments, tiredness (2% to 41%), and bleeding (0.03% to 38%). Feelings of faintness and syncope were uncommon, with an incidence of 0% to 0.3%. Feelings of relaxation were reported by as many as 86% of patients. Pneumothorax was rare, occurring only twice in nearly a quarter of a million treatments.

CONCLUSIONS

Although the incidence of minor adverse events associated with acupuncture may be considerable, serious adverse events are rare. Those responsible for establishing competence in acupuncture should consider how to reduce these risks.

Sublethal concentrations of prion peptide PrP106-126 or the amyloid beta peptide of Alzheimer's disease activates expression of proapoptotic markers in primary cortical neurons

Neurodegenerative disorders such as prion diseases and Alzheimer's disease (AD) are characterized by neuronal dysfunction and accumulation of amyloidogenic protein. In vitro studies have demonstrated that these amyloidogenic proteins can induce cellular oxidative stress and therefore may contribute to the neuronal dysfunction observed in these illnesses. Although the neurotoxic pathways are not fully elucidated, recent studies in AD have demonstrated up-regulation of caspases in neurons treated with amyloid beta (Abeta) peptide, suggesting involvement of apoptotic processes. To examine the role of proapoptotic pathways in prion diseases we treated primary mouse cortical neurons with the toxic prion protein peptide PrP106-126 and measured caspase activation and annexin V binding. We found that PrP106-126 induced a rapid and marked elevation in caspase 3, 6, and 8-like activity in neuronal cultures. Increased annexin V binding was observed predominantly on cortical cell neurites in peptide-treated cultures. Interestingly, these effects were induced by sublethal (5-50 microM) or lethal (100-200 microM) concentrations of PrP106-126. Sublethal concentrations of PrP106-126 maintained elevated caspase activation for at least 10 days with no loss of cell viability. Abeta1-40 also up-regulated caspase 3 activity and annexin V binding at both sublethal (5 microM) and lethal (25 microM) concentrations. There were no changes to proapoptotic marker expression in cultures treated with scrambled PrP106-126 (200 microM) or Abeta1-28 (25 microM) peptides. These studies demonstrate that amyloidogenic peptides can induce prolonged activation of proapoptotic marker expression in cultured neurons even at sublethal concentrations. These effects could contribute to chronic neuronal dysfunction and increase susceptibility to additional metabolic insults in neurodegenerative disorders. If so, targeting of therapeutic strategies against neuronal caspase activation early in the disease course could be beneficial in AD and prion diseases.

Homocysteine potentiates copper- and amyloid beta peptide-mediated toxicity in primary neuronal cultures: possible risk factors in the Alzheimer's-type neurodegenerative pathways

Oxidative stress may have an important role in the progression of neurodegenerative disorders such as Alzheimer's disease (AD) and prion diseases. Oxidative damage could result from interactions between highly reactive transition metals such as copper (Cu) and endogenous reducing and/or oxidizing molecules in the brain. One such molecule, homocysteine, a thiol-containing amino acid, has previously been shown to modulate Cu toxicity in HeLa and endothelial cells in vitro. Due to a possible link between hyperhomocysteinemia and AD, we examined whether interaction between homocysteine and Cu could potentiate Cu neurotoxicity. Primary mouse neuronal cultures were treated with homocysteine and either Cu (II), Fe (II or III) or Zn (II). Homocysteine was shown to selectively potentiate toxicity from low micromolar concentrations of Cu. The toxicity of homocysteine/Cu coincubation was dependent on the ability of homocysteine to reduce Cu (II) as reflected by the inhibition of toxicity with the Cu (I)-specific chelator, bathocuproine disulphonate. This was supported by data showing that homocysteine reduced Cu (II) more effectively than cysteine or methionine but did not reduce Fe (III) to Fe (II). Homocysteine also generated high levels of hydrogen peroxide in the presence of Cu (II) and promoted Abeta/Cu-mediated hydrogen peroxide production and neurotoxicity. The potentiation of metal toxicity did not involve excitotoxicity as ionotropic glutamate receptor antagonists had no effect on neurotoxicity. Homocysteine alone also had no effect on neuronal glutathione levels. These studies suggest that increased copper and/or homocysteine levels in the elderly could promote significant oxidant damage to neurons and may represent additional risk factor pathways which conspire to produce AD or related neurodegenerative conditions.

Amyloidogenicity and neurotoxicity of peptides corresponding to the helical regions of PrP(C)

An alpha-helical to beta-sheet conformational change in the prion protein, PrP(C), is believed to be causative in transmissible spongiform encephalopathies. Recent nuclear magnetic resonance structures of PrP(C) have identified three helical regions in the normal full-length protein. We have synthesised peptides corresponding to these helical regions (PrP144-154, helical region one; PrP178-193, helical region two; and PrP198-218, helical region three). Circular dichroism results show that the peptide corresponding to helical region one is unstructured, while peptides corresponding to the second and third helical regions have a high propensity to form beta-sheet structure in a pH-dependent manner in aqueous solutions. Peptides corresponding to the second helical region, PrP180-193 and PrP178-193, are the only ones that form amyloid by electron microscopy and congo red birefringence. PrP178-193 and the amyloidogenic Alzheimer's disease Abeta25-25 peptide were found to promote Cu (II)-induced lipid peroxidation and cytotoxicity in primary neuronal cultures, while PrP144-154, PrP198-218 and the nonamyloidogenic Abeta1-28 had no effect on Cu (II) toxicity. There was no increase in toxicity induced by PrP178-193 in cultures treated with Fe (II) or hydrogen peroxide, indicating a preferential modulatory effect on Cu (II) toxicity by PrP178-193. The data suggest that the PrP178-193 peptide has both structural and bioactive properties in common with Abeta25-35 and that the second putative helical region of PrP could be involved in modulation of Cu (II)-mediated toxicity in neurons during prion disease.

A blinded investigation into the accuracy of reflexology charts

OBJECTIVES

Reflexology is an increasingly popular complementary therapy in which parts of the body are deemed to be represented on the soles of the feet. The aim of this study was to investigate whether this representation can be used as a valid method of diagnosis.

METHODS

Three experienced reflexologists took part in this study. Eighteen adults with one or more of six specified conditions were identified from primary care records. Two reflexologists, who were blinded to the patients' conditions and monitored, then examined each patient's feet and rated the probability that each of the six conditions was present.

RESULTS

There is little evidence that the distribution of ratings vary with the status of the condition. Receiver operating curves suggest that this diagnostic method is very poor at distinguishing between the presence and absence of conditions. Inter-rater reliability (kappa) scores were very low, providing no evidence of agreement between the examiners.

CONCLUSION

Despite certain limitations to the data provided by this study, the results do not suggest that reflexology techniques are a valid method of diagnosis.

Acupuncture for episodic tension-type headache: a multicentre randomized controlled trial

A multicentre, randomized clinical trial was undertaken to test the hypothesis that acupuncture is more efficacious than sham control procedure in the prevention of episodic tension-type headache. Fifty subjects were randomized to receive a course of treatment with either brief acupuncture or a sham procedure. Subjects were followed up for 3 months. Changes in headache were assessed by daily diary, the primary outcome measure being the number of days with headache. No significant differences were found between the changes in the two groups for any measure at any time point. Results also show that patient blinding was successful. In conclusion, this study does not provide evidence that this form of acupuncture is effective in the prevention of episodic tension-type headache.

Economic analysis of complementary medicine: a systematic review

OBJECTIVE

To review systematically all reports of economic analysis of complementary and alternative medicine.

METHOD

Searches were performed in Medline, Embase and AMED for reports of cost description, cost comparison, cost effectiveness, or cost benefit studies. Prospective studies that investigated comparative groups were considered to be of higher quality.

RESULTS

A total of 34 reports was included. Retrospective studies in which a range of therapies are provided in primary care suggest that these may reduce referral and treatment costs, but prospective studies suggest that complementary medicine is an additional expense and does not substitute for orthodox care. For individual therapies, one thorough but retrospective study suggests that carefully targeted acupuncture may reduce referral costs for musculoskeletal problems. One large pragmatic study of spinal manipulative therapy suggests that this treatment may reduce the societal costs of back pain, but four controlled trials found that manipulative therapy does not reduce the costs incurred by the back pain patients themselves or by their health insurance provider.

CONCLUSION

Spinal manipulative therapy for back pain may offer cost savings to society, but it does not save money for the purchaser. There is a paucity of rigorous studies that could provide conclusive evidence of differences in costs and outcomes between other complementary therapies and orthodox medicine. The evidence from methodologically flawed studies is contradicted by more rigorous studies, and there is a need for high quality investigations of the costs and benefits of complementary medicine.

Efficacy of acupuncture as a treatment for tinnitus: a systematic review

BACKGROUND

Tinnitus is a prevalent condition for which patients may seek treatment with acupuncture since no conventional treatment has been shown to be effective.

OBJECTIVE

To summarize and critically review all randomized controlled trials on the efficacy of acupuncture as a treatment for tinnitus.

DATA SOURCES

Four independent computerized literature searches (MEDLINE, Cochrane Controlled Trials Register, Embase, and CISCOM) were conducted in December 1998 using the key words acupuncture and tinnitus.

STUDY SELECTION

All randomized controlled trials that compared any form of acupuncture with any control intervention in the treatment of tinnitus were included.

DATA EXTRACTION

Data were extracted by 2 authors independently. The methodological quality of the included randomized controlled trials was assessed using the Jadad score.

DATA SYNTHESIS

Six randomized controlled trials were included in the review, 4 of which used crossover design. Four studies used manual acupuncture and 2 used electroacupuncture. Five of 6 studies used inconsistent acupoints. Three studies scored 3 points or more on the Jadad scale.

MAIN OUTCOME MEASURES

Outcome measurements were visual analog scale scores for loudness, annoyance, and awareness of tinnitus; subjective severity scale scores for tinnitus; or Nottingham Health Profile scores.

RESULTS

Two unblinded studies showed a positive result, whereas 4 blinded studies showed no significant effect of acupuncture.

CONCLUSION

Acupuncture has not been demonstrated to be efficacious as a treatment for tinnitus on the evidence of rigorous randomized controlled trials.

Are acupuncture points tender? A blinded study of Spleen 6

OBJECTIVES

To explore the methodology for investigating the tenderness of acupuncture points, with particular reference to the hypothesis that the point Spleen 6 (SP6) is more tender in women than in men.

DESIGN

Single-blind, observational study with volunteers.

SETTING

University of Exeter, U.K.

SUBJECTS

Student volunteers, 13 male and 13 female.

OUTCOME MEASURES

Pressure thresholds at SP6, a control acupuncture point Stomach 36, and two nonacupuncture control sites in each leg were measured weekly for 4 weeks.

RESULTS

No statistically significant differences were found between the pressure thresholds of SP6 in women and those in men.

CONCLUSION

The present study provides no strong evidence to support the hypothesis that the acupuncture point SP6 is more tender in women and in men. Recommendations for further investigations are discussed.

Hypnotherapy for smoking cessation

BACKGROUND

Hypnotherapy is widely promoted as a method for aiding smoking cessation. It is proposed to act on underlying impulses to weaken the desire to smoke or strengthen the will to stop.

OBJECTIVES

The objective of this review was to evaluate the effects of hypnotherapy for smoking cessation.

SEARCH STRATEGY

We searched the Cochrane Tobacco Addiction Group trials register.

SELECTION CRITERIA

We considered randomised trials of hypnotherapy which reported smoking cessation rates at least six months after the beginning of treatment.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted data on the type of subjects, the type and duration of the hypnotherapy, the nature of the control group,the outcome measures, method of randomisation, and completeness of follow-up. The main outcome measure was abstinence from smoking after at least six months follow-up in patients smoking at baseline. We used the most rigorous definition of abstinence in each trial, and biochemically validated rates where available. Subjects lost to follow-up were counted as smokers. Where possible, we performed meta-analysis using a fixed effects model.

MAIN RESULTS

Nine studies compared hypnotherapy with 14 different control interventions. There was significant heterogeneity between the results of the individual studies, with conflicting results for the effectiveness of hypnotherapy compared to no treatment or to advice. We therefore did not attempt to calculate pooled odds ratios for the overall effect of hypnotherapy. There was no evidence of an effect of hypnotherapy compared to rapid smoking or psychological treatment.

REVIEWER'S CONCLUSIONS

We have not shown that hypnotherapy has a greater effect on six month quit rates than other interventions or no treatment. The effects of hypnotherapy on smoking cessation claimed by uncontrolled studies were not confirmed by analysis of randomised controlled trials.

A meta-analysis of acupuncture techniques for smoking cessation

OBJECTIVE

To determine the effectiveness of acupuncture for smoking cessation and to examine whether any individual aspect of trials is associated with an effect.

DATA SOURCES

All randomised controlled trials of acupuncture for smoking cessation that were listed in computerised databases or reference lists of relevant articles.

STUDY SELECTION

All randomised single-blind studies that compared acupuncture with sham acupuncture.

DATA EXTRACTION

Methodological data were extracted for quality assessment. Outcome data were extracted for rates of total smoking cessation at three intervals: early after treatment and after six and 12 months follow up.

DATA SYNTHESIS

Results were expressed as odds ratios of success over failure in intervention over control groups. The combined odds ratio for all studies was calculated. Repeated meta-analyses were subsequently performed on subsets of studies combined according to defined characteristics: acupuncture technique, number of attendances, country of origin, status of journal, and control procedure. The overall quality of studies was poor. The combined odds ratio for smoking cessation calculated for the earliest results after the end of treatment was 1.20 (95% confidence intervals (95% CIs) = 0.98 to 1.48). The combined odds ratio for smoking cessation after six months was 1.29 (95% CI = 0.82 to 2.01), and after 12 months was 1.03 (95% CI = 0.73 to 1.46). There were no significant effects of relevance among subsets of studies grouped according to defined characteristics.

CONCLUSIONS

Acupuncture was not superior to sham acupuncture for smoking cessation; no particular aspect of acupuncture technique was associated with a positive effect. The conclusions are limited by methodological inadequacies of studies and by the absence of testable hypotheses; design of future trials should avoid these deficiencies.

Prion protein-deficient neurons reveal lower glutathione reductase activity and increased susceptibility to hydrogen peroxide toxicity

The prion protein (PrP) has a central role in the pathogenesis of transmissible spongiform encephalopathies (TSE). Accumulating evidence suggests that normal cellular PrP (PrP(c)) may be involved in copper homeostasis and modulation of copper/zinc superoxide dismutase (Cu/ZnSOD) activity in neurons. Hydrogen peroxide (H(2)O(2)) is a toxic reactive oxygen species generated through normal cellular respiration, and neurons contain two important peroxide detoxifying systems (glutathione pathway and catalase). To determine whether PrP expression affects neuronal resistance to H(2)O(2), we exposed primary cerebellar granule neuron cultures derived from PrP knockout (PrP(-/-)) and wild-type (WT) mice to H(2)O(2) for 3, 6, and 24 hours. The PrP(-/-) neurons were significantly more susceptible to H(2)O(2) toxicity than WT neurons after 6 and 24 hours' exposure. The increased H(2)O(2) toxicity may be related to a significant decrease in glutathione reductase activity measured in PrP(-/-) neurons both in vitro and in vivo. This was supported by the finding that inhibition of GR activity with 1,3-bis(2-chloroethyl)-1-nitrosurea (BCNU) increased H(2)O(2) toxicity in WT neurons over the same exposure period. The PrP toxic peptide PrP106-126 significantly reduced neuronal glutathione reductase activity and increased susceptibility to H(2)O(2) toxicity in neuronal cultures suggesting that PrP toxicity in vivo may involve altered glutathione reductase activity. Our results suggest the pathophysiology of prion diseases may involve perturbed PrP(c) function with increased vulnerability to peroxidative stress.

The Alzheimer's disease amyloid precursor protein modulates copper-induced toxicity and oxidative stress in primary neuronal cultures

The amyloid precursor protein (APP) of Alzheimer's disease can reduce copper (II) to copper (I) in a cell-free system potentially leading to increased oxidative stress in neurons. We used neuronal cultures derived from APP knock-out (APP(-/-)) and wild-type (WT) mice to examine the role of APP in copper neurotoxicity. WT cortical, cerebellar, and hippocampal neurons were significantly more susceptible than their respective APP(-/-) neurons to toxicity induced by physiological concentrations of copper but not by zinc or iron. There was no difference in copper toxicity between APLP2(-/-) and WT neurons, demonstrating specificity for APP-associated copper toxicity. Copper uptake was the same in WT and APP(-/-) neurons, suggesting APP may interact with copper to induce a localized increase in oxidative stress through copper (I) production. This was supported by significantly higher levels of copper-induced lipid peroxidation in WT neurons. Treatment of neuronal cultures with a peptide corresponding to the human APP copper-binding domain (APP142-166) potentiated copper but not iron or zinc toxicity. Incubation of APP142-166 with low-density lipoprotein (LDL) and copper resulted in significantly increased lipid peroxidation compared to copper and LDL alone. Substitution of the copper coordinating histidine residues with asparagines (APP142-166(H147N, H149N, H151N)) abrogated the toxic effects. A peptide corresponding to the zinc-binding domain (APP181-208) failed to induce copper or zinc toxicity in neuronal cultures. These data support a role for the APP copper-binding domain in APP-mediated copper (I) generation and toxicity in primary neurons, a process that has important implications for Alzheimer's disease and other neurodegenerative disorders.

The hydrophobic core sequence modulates the neurotoxic and secondary structure properties of the prion peptide 106-126

The neurodegeneration seen in spongiform encephalopathies is believed to be mediated by protease-resistant forms of the prion protein (PrP). A peptide encompassing residues 106-126 of human PrP has been shown to be neurotoxic in vitro. The neurotoxicity of PrP106-126 appears to be dependent upon its adoption of an aggregated fibril structure. To examine the role of the hydrophobic core, AGAAAAGA, on PrP106-126 toxicity, we performed structure-activity analyses by substituting two or more hydrophobic residues for the hydrophilic serine residue to decrease its hydrophobicity. A peptide with a deleted alanine was also synthesized. We found all the peptides except the deletion mutant were no longer toxic on mouse cerebellar neuronal cultures. Circular dichroism analysis showed that the nontoxic PrP peptides had a marked decrease in beta-sheet structure. In addition, the mutants had alterations in aggregability as measured by turbidity, Congo red binding, and fibril staining using electron microscopy. These data show that the hydrophobic core sequence is important for PrP106-126 toxicity probably by influencing its assembly into a neurotoxic structure. The hydrophobic sequence may similarly affect aggregation and toxicity observed in prion diseases.

Copper levels are increased in the cerebral cortex and liver of APP and APLP2 knockout mice

The pathological process in Alzheimer's disease (AD) involves amyloid beta (Abeta) deposition and neuronal cell degeneration. The neurotoxic Abeta peptide is derived from the amyloid precursor protein (APP), a member of a larger gene family including the amyloid precursor-like proteins, APLP1 and APLP2. The APP and APLP2 molecules contain metal binding sites for copper and zinc. The zinc binding domain (ZnBD) is believed to have a structural rather than a catalytic role. The activity of the copper binding domain (CuBD) is unknown, however, APP reduces copper (II) to copper (I) and this activity could promote copper-mediated neurotoxicity. The expression of APP and APLP2 in the brain suggests they could have an important direct or indirect role in neuronal metal homeostasis. To examine this, we measured copper, zinc and iron levels in the cerebral cortex, cerebellum and selected non-neuronal tissues from APP (APP(-/-)) and APLP2 (APLP2(-/-)) knockout mice using atomic absorption spectrophotometry. Compared with matched wild-type (WT) mice, copper levels were significantly elevated in both APP(-/-) and APLP2(-/-) cerebral cortex (40% and 16%, respectively) and liver (80% and 36%, respectively). Copper levels were not significantly different between knockout and WT cerebellum, spleen or serum samples. There were no significant differences observed between APP(-/-), APLP2(-/-) and WT mice zinc or iron levels in any tissue examined. These findings indicate APP and APLP2 expression specifically modulates copper homeostasis in the liver and cerebral cortex, the latter being a region of the brain particularly involved in AD. Perturbations to APP metabolism and in particular, its secretion or release from neurons may alter copper homeostasis resulting in increased Abeta accumulation and free radical generation. These data support a novel mechanism in the APP/Abeta pathway which leads to AD.

Amyloid beta

Amyloid beta (A beta) is a 39-43 residue amyloidogenic peptide that is deposited into the extracellular amyloid plaques which characterize an Alzheimer's disease (AD) brain. A beta is derived from the amyloid precursor protein (APP) and undergoes a toxic conformational change (gain of toxic function). The length of the A beta peptide dramatically influences its properties with the longer 42 and 43 residue species being more amyloidogenic. The genetics of familial AD (FAD) supports a central role for A beta in AD since mutations in the FAD causing genes APP and the presenilins (PS1 and PS2) increase the formation of A beta 42,43. Considerable activity is directed towards A beta as a therapeutic target. These strategies aim to inhibit A beta synthesis, A beta fibril formation, its toxic actions on cells or promote its clearance from the brain.