RESUMO
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.
Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Encéfalo/metabolismo , Exposição Ambiental/análise , Doenças Neurodegenerativas/etiologia , Animais , Técnicas de Cultura de Células , HumanosRESUMO
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.
Assuntos
Transtornos Traumáticos Cumulativos/patologia , Derme/patologia , Músculo Esquelético/patologia , Transdução de Sinais , Substância P/metabolismo , Tendões/patologia , Animais , Restrição Calórica , Colágeno Tipo I/metabolismo , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibrose , Proteínas Musculares/metabolismo , Fosforilação , Ratos Sprague-Dawley , Receptores da Neurocinina-1/metabolismo , Análise e Desempenho de Tarefas , Tendinopatia/patologia , Fator de Crescimento Transformador beta1/metabolismoRESUMO
BACKGROUND: Patients with cervical or high-thoracic spinal cord injury (SCI) often present reduced gastric emptying and early satiety. Ghrelin provokes motility via gastric vagal neurocircuitry and ghrelin receptor agonists offer a therapeutic option for gastroparesis. We have previously shown that experimental high-thoracic injury (T3-SCI) diminishes sensitivity to another gastrointestinal peptide, cholecystokinin. This study tests the hypothesis that T3-SCI impairs the vagally mediated response to ghrelin. METHODS: We investigated ghrelin sensitivity in control and T3-SCI rats at 3-days or 3-weeks after injury utilizing: (i) acute (3-day post-injury) fasting and post-prandial serum levels of ghrelin; (ii) in vivo gastric reflex recording following intravenous or central brainstem ghrelin; and (iii) in vitro whole cell recording of neurons within the dorsal motor nucleus of the vagus (DMV). KEY RESULTS: The 2-day food intake of T3-SCI rats was reduced while fasting serum ghrelin levels were higher than in controls. Intravenous and fourth ventricle ghrelin increased in vivo gastric motility in fasted 3-day control rats but not fasted T3-SCI rats. In vitro recording of DMV neurons from 3-day T3-SCI rats were insensitive to exogenous ghrelin. For each measure, vagal responses returned after 3-weeks. CONCLUSIONS AND INFERENCES: Hypophagia accompanying T3-SCI produces a significant and physiologically appropriate elevation in serum ghrelin levels. However, higher ghrelin levels did not translate into increased gastric motility in the acute stage of T3-SCI. We propose that this may reflect diminished sensitivity of peripheral vagal afferents to ghrelin or a reduction in the responsiveness of medullary gastric vagal neurocircuitry following T3-SCI.
Assuntos
Motilidade Gastrointestinal , Grelina/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Animais , Vértebras Cervicais , Modelos Animais de Doenças , Ingestão de Alimentos , Motilidade Gastrointestinal/efeitos dos fármacos , Grelina/administração & dosagem , Grelina/sangue , Masculino , Bulbo/efeitos dos fármacos , Bulbo/fisiopatologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos Long-Evans , Traumatismos da Medula Espinal/sangue , Vértebras Torácicas , Nervo VagoRESUMO
Amyotrophic lateral sclerosis (ALS) is the most common form of motor neuron disease, a fatal degenerative disorder in which motor neurons in the central nervous system (CNS) progressively deteriorate. Most cases of ALS are sporadic, but 10% are familial and mutations affecting the copper (Cu)-dependent antioxidant Cu/Zn-superoxide dismutase (SOD1) are the most common familial cause. Cu malfunction is evident in CNS tissue from transgenic mice that over-express mutant SOD1 and modulating Cu bioavailability in the CNS provides positive therapeutic outcomes. In the present study we assessed levels of Cu and Zn, SOD activity, and SOD1 protein levels in CNS and non-CNS tissue from transgenic mutant SOD1 mice (SOD1(G37R)) and non-transgenic controls. Physiological SOD1 binds one structural Zn and one catalytic Cu per subunit. Due to over-expression of the transgene, SOD activity and SOD1 protein levels are elevated in all tissues examined from the SOD1(G37R) mice and a commensurate increase in Zn is evident. There is a comparable increase in Cu in non-CNS tissue, but the increase in Cu in the SOD1(G37R) mouse brain is limited and there is no increase in Cu in the spinal cord. The limited change in CNS Cu is associated with a strong disparity between SOD1 protein and SOD activity in the brain and spinal cord. We hypothesise that the limited capacity for CNS tissue to respond to an increased requirement for bioavailable Cu contributes to CNS vulnerability in ALS.
Assuntos
Esclerose Lateral Amiotrófica/patologia , Sistema Nervoso Central/patologia , Cobre/metabolismo , Modelos Animais de Doenças , Mutação , Superóxido Dismutase-1/fisiologia , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Animais , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Cobre/administração & dosagem , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos TransgênicosRESUMO
Patients with Parkinson's disease often experience non-motor symptoms including constipation, which manifest prior to the onset of debilitating motor signs. Understanding the causes of these non-motor deficits and developing disease modifying therapeutic strategies has the potential to prevent disease progression. Specific neuronal subpopulations were reduced within the myenteric plexus of mice 21 days after intoxication by the intraperitoneal administration of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) and was associated with a reduction in stool frequency, indicative of intestinal dysfunction. Oral administration of the divalent copper complex, Cu(II)(atsm), which has been shown to be neuroprotective and restore motor performance to MPTP lesioned mice, improved stool frequency and was correlated with restoration of neuronal subpopulations in the myenteric plexus of MPTP lesioned mice. Restoration of intestinal function was associated with reduced enteric glial cell reactivity and reduction of markers of inflammation. Therapeutics that have been shown to be neuroprotective in the central nervous system, such as Cu(II)(atsm), therefore also provide symptom relief and are disease modifying in the intestinal tract, suggesting that there is a common cause of Parkinson's disease pathogenesis in the enteric nervous system and central nervous system.
Assuntos
Constipação Intestinal/tratamento farmacológico , Defecação/efeitos dos fármacos , Intoxicação por MPTP/tratamento farmacológico , Plexo Mientérico/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Compostos Organometálicos/farmacologia , Tiossemicarbazonas/farmacologia , Administração Oral , Animais , Constipação Intestinal/complicações , Constipação Intestinal/metabolismo , Constipação Intestinal/fisiopatologia , Complexos de Coordenação , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Corpo Estriado/fisiopatologia , Defecação/fisiologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Injeções Intraperitoneais , Intoxicação por MPTP/complicações , Intoxicação por MPTP/metabolismo , Intoxicação por MPTP/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Plexo Mientérico/metabolismo , Plexo Mientérico/fisiopatologia , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/patologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Substância Negra/fisiopatologiaRESUMO
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.
RESUMO
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.
Assuntos
Mitocôndrias/fisiologia , Terapia de Alvo Molecular/métodos , Doenças Neurodegenerativas/fisiopatologia , Elementos de Transição/metabolismo , Cátions/uso terapêutico , Quelantes/uso terapêutico , Homeostase , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Doenças Neurodegenerativas/tratamento farmacológicoRESUMO
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.
Assuntos
Treinamento Autógeno , Cefaleia do Tipo Tensional/terapia , Ensaios Clínicos Controlados como Assunto , HumanosRESUMO
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.
Assuntos
Terapia por Acupuntura , Abandono do Hábito de Fumar/métodos , Fumar/terapia , Acupressão , Terapia por Estimulação Elétrica , Humanos , Terapia a Laser , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
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.
Assuntos
Envelhecimento , Evolução Biológica , Reprodução/fisiologia , Dinâmica Populacional , Seleção Genética , Taxa de SobrevidaRESUMO
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.
Assuntos
Caracois Helix/fisiologia , Contração Miocárdica/fisiologia , Óxido Nítrico/fisiologia , Animais , Depressão Química , Relação Dose-Resposta a Droga , Coração/efeitos dos fármacos , Coração/fisiologia , Técnicas In Vitro , Contração Miocárdica/efeitos dos fármacos , S-Nitroso-N-Acetilpenicilamina/farmacologia , Caramujos/fisiologiaRESUMO
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.
Assuntos
Angioplastia Coronária com Balão/psicologia , Ansiedade/terapia , Treinamento Autógeno , Doença das Coronárias/psicologia , Idoso , Ansiedade/etiologia , Doença das Coronárias/fisiopatologia , Doença das Coronárias/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Desistentes do Tratamento , Qualidade de Vida , Tamanho da AmostraRESUMO
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.
Assuntos
Terapia por Acupuntura/normas , Dismenorreia/terapia , Hipertensão/prevenção & controle , Infertilidade Feminina/terapia , Saúde da Mulher , Terapia por Acupuntura/métodos , Ensaios Clínicos Controlados como Assunto , Dismenorreia/prevenção & controle , Europa (Continente) , Feminino , Humanos , Hipertensão/etiologia , Infertilidade Feminina/prevenção & controle , Menopausa , Projetos de PesquisaRESUMO
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.
Assuntos
Terapia por Acupuntura , Abandono do Hábito de Fumar/métodos , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
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.
Assuntos
Analgesia por Acupuntura/métodos , Dor nas Costas/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
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.
Assuntos
Asma/terapia , Terapia de Relaxamento , Ansiedade/terapia , Asma/psicologia , Biorretroalimentação Psicológica/métodos , Humanos , Hipnose/métodos , Meditação/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estresse Psicológico/complicações , Estresse Psicológico/terapiaRESUMO
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.
Assuntos
Araquidonato 5-Lipoxigenase/metabolismo , Ácido Araquidônico/metabolismo , Neurônios/efeitos dos fármacos , Neurotoxinas/toxicidade , Fragmentos de Peptídeos/toxicidade , Doenças Priônicas/enzimologia , Príons/metabolismo , Príons/toxicidade , Animais , Anexina A5/efeitos dos fármacos , Anexina A5/metabolismo , Anti-Inflamatórios não Esteroides/farmacologia , Sítios de Ligação/efeitos dos fármacos , Sítios de Ligação/fisiologia , Caspase 3 , Caspases/efeitos dos fármacos , Caspases/metabolismo , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/enzimologia , Córtex Cerebelar/efeitos dos fármacos , Córtex Cerebelar/enzimologia , Inibidores Enzimáticos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Memantina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/enzimologia , Doenças Priônicas/fisiopatologia , Quinacrina/farmacologiaRESUMO
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.
Assuntos
Terapia por Acupuntura , Reabilitação do Acidente Vascular Cerebral , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Resultado do TratamentoRESUMO
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.
Assuntos
Cobre/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/toxicidade , Príons/metabolismo , Príons/toxicidade , Zinco/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação/efeitos dos fármacos , Resinas de Troca de Cátion/farmacologia , Células Cultivadas , Cerebelo/citologia , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Quelantes/farmacologia , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Espectroscopia de Ressonância de Spin Eletrônica , Histidina/genética , Humanos , Espectrometria de Massas , Metionina/genética , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Nefelometria e Turbidimetria , Ressonância Magnética Nuclear Biomolecular , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/ultraestrutura , Príons/genética , Príons/ultraestrutura , Estrutura Secundária de Proteína , Resinas Sintéticas , UltracentrifugaçãoRESUMO
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.