Sleep and circadian rhythm dysregulation in schizophrenia.

Sleep-onset and maintenance insomnia is a common symptom in schizophrenic patients regardless of either their medication status (drug-naive or previously treated) or the phase of the clinical course (acute or chronic). Regarding sleep architecture, the majority of studies indicate that non-rapid eye movement (NREM), N3 sleep and REM sleep onset latency are reduced in schizophrenia, whereas REM sleep duration tends to remain unchanged. Many of these sleep disturbances in schizophrenia appear to be caused by abnormalities of the circadian system as indicated by misalignments of the endogenous circadian cycle and the sleep-wake cycle. Circadian disruption, sleep onset insomnia and difficulties in maintaining sleep in schizophrenic patients could be partly related to a presumed hyperactivity of the dopaminergic system and dysfunction of the GABAergic system, both associated with core features of schizophrenia and with signaling in sleep and wake promoting brain regions. Since multiple neurotransmitter systems within the CNS can be implicated in sleep disturbances in schizophrenia, the characterization of the neurotransmitter systems involved remains a challenging dilemma.

Measurement of melatonin in body fluids: standards, protocols and procedures.

BACKGROUND AND PURPOSE: The circadian rhythm of melatonin in saliva or plasma, or of the melatonin metabolite 6-sulfatoxymelatonin (a6MTs) in urine, is a defining feature of suprachiasmatic nucleus (SCN) function, the body's endogenous oscillatory pacemaker. The primary objective of this review is to ascertain the clinical benefits and limitations of current methodologies employed for detection and quantification of melatonin in biological fluids and tissues. DATA IDENTIFICATION: A search of the English-language literature (Medline) and a systematic review of published articles were carried out. STUDY SELECTION: Articles that specified both the methodology for quantifying melatonin and indicated the clinical purpose were chosen for inclusion in the review. DATA EXTRACTION: The authors critically evaluated the methodological issues associated with various tools and techniques (e.g. standards, protocols, and procedures). RESULTS OF DATA SYNTHESIS: Melatonin measurements are useful for evaluating problems related to the onset or offset of sleep and for assessing phase delays or advances of rhythms in entrained individuals. They have also become an important tool for psychiatric diagnosis, their use being recommended for phase typing in patients suffering from sleep and mood disorders. Additionally, there has been a continuous interest in the use of melatonin as a marker for neoplasms of the pineal region. Melatonin decreases such as found with aging are or post pinealectomy can cause alterations in the sleep/wake cycle. The development of sensitive and selective methods for the precise detection of melatonin in tissues and fluids has increasingly been shown to have direct relevance for clinical decision making. CONCLUSIONS: Due to melatonin's low concentration, as well as the coexistence of numerous other compounds in the blood, the routine determination of melatonin has been an analytical challenge. The available evidence indicates however that these challenges can be overcome and consequently that evaluation of melatonin's presence and activity can be an accessible and useful tool for clinical diagnosis.

Supporting cancer patients in Jamaica--a needs assessment survey.

OBJECTIVE: Global cancer incidence is rising rapidly particularly in the developing world where a majority of people present with advanced disease. In the English-speaking Caribbean, there is very little published data on the needs of cancer patients, their caregivers or those of allied health professionals. The research team sought to redress this balance by undertaking a needs assessment survey in the South Eastern Health Region of Jamaica to identify unmet needs and to make recommendations for improved service delivery. METHODS: A mixed methods, cross-sectional study design was used involving formal and semi-formal interviews and focus group discussions. RESULTS: The study results indicated that there were significant barriers to accessing healthcare. These included prohibitive costs of diagnosis and treatment, a mistrust of and poor communication with doctors, compounded by people's fears, belief in folk wisdom and lack of knowledge about cancer. Recommendations offered by the study participants focussed on a community-based model of support to address the multiple needs of people facing life-limiting illness and their caregivers. Healthcare practitioners recommended the development of specific policies, targeting, in particular improved drug availability and palliative care education in order to guide development of appropriate services for the large numbers of cancer patients in need. CONCLUSION: A multiplicity of unmet needs was identified by cancer patients, their caregivers and allied health professionals. Recommendations by study participants and the authors echoed the guidelines as set out by the World Health Organization (WHO) in its 1990 Public Health Model for the integration of palliative care into existing healthcare systems.

Melatonin as a therapeutic tool in ophthalmology: implications for glaucoma and uveitis.

Several lines of evidence support the view that increased free radical generation and altered nitric oxide (NO) metabolism play a role in the pathogenesis of highly prevalent ocular diseases, such as glaucoma and uveitis. Data are discussed indicating that melatonin, being an efficient antioxidant that displays antinitridergic properties, has a promising role in the treatment of these ocular dysfunctions. Melatonin synthesis occurs in the eye of most species, and melatonin receptors are localized in different ocular structures. In view of the fact that melatonin lacks significant adverse collateral effects even at high doses, the application of melatonin could potentially protect ocular tissues by effectively scavenging free radicals and excessive amounts of NO generated in the glaucomatous or uveitic eye.

Supporting cancer patients in Jamaica: a needs assessment survey / Apoyo a los pacientes de cáncer en Jamaica: una encuesta para la evaluación de las necesidades

OBJECTIVE: Global cancer incidence is rising rapidly, particularly in the developing world where a majority of people present with advanced disease. In the English-speaking Caribbean, there is very little published data on the needs of cancer patients, their caregivers or those of allied health professionals. The research team sought to redress this balance by undertaking a needs assessment survey in the South Eastern Health Region of Jamaica to identify unmet needs and to make recommendations for improved service delivery. METHODS: A mixed methods, cross-sectional study design was used involving formal and semi-formal interviews and focus group discussions. RESULTS: The study results indicated that there were significant barriers to accessing healthcare. These included prohibitive costs of diagnosis and treatment, a mistrust of, and poor communication with doctors, compounded by people's fears, belief in folk wisdom and lack of knowledge about cancer. Recommendations offered by the study participants focussed on a community-based model of support to address the multiple needs of people facing life-limiting illness and their caregivers. Healthcare practitioners recommended the development of specific policies, targeting, in particular, improved drug availability and palliative care education in order to guide development of appropriate services for the large numbers of cancer patients in need. CONCLUSION: A multiplicity of unmet needs was identified by cancer patients, their caregivers and allied health professionals. Recommendations by study participants and the authors echoed the guidelines as set out by the World Health Organization (WHO) in its 1990 Public Health Model for the integration of palliative care into existing healthcare systems.

OBJETIVO: La incidencia de cáncer global está aumentado rápidamente, particularmente en el mundo en vías de desarrollo, dónde un gran número de personas se presentan con la enfermedad en estado avanzado. En el Caribe angloparlante, se ha publicado muy poca información sobre las necesidades de los pacientes de cáncer, sus cuidadores o los profesionales de salud asociados. El equipo de investigación buscó restablecer el equilibrio emprendiendo un estudio de evaluación de las necesidades en la Región de Salud Suroriental de Jamaica, para identificar las necesidades no satisfechas y hacer recomendaciones encaminadas a mejorar la prestación de servicios. MÉTODOS: Se empleo un diseño de estudio transversal con métodos mixtos, contentivo de entrevistas formales y semi-formales así como discusiones de grupos focales. RESULTADOS: Los resultados del estudio indicaron que había barreras considerables para el acceso a la atención a la salud. Estas comprendían costos prohibitivos para el diagnóstico y el tratamiento, desconfianza y pobre comunicación con los doctores, agravada por los miedos de la gente, la creencia en la sabiduría popular, y la falta de conocimientos sobre el cáncer. Las recomendaciones ofrecidas por los participantes en el estudio se centran en un modelo basado en la comunidad. Este modelo permite abordar las múltiples necesidades de las personas que enfrentan enfermedades limitantes de la vida, así como las necesidades de sus cuidadores. Los practicantes de cuidados de la salud recomendaron el desarrollo de políticas específicas, encaminadas especialmente a mejorar la disponibilidad de medicamentos y educación de cuidados paliativos para guiar el desarrollo de servicios apropiados para el gran número de pacientes necesitados, enfermos de cáncer. CONCLUSIÓN: Se identificaron una multiplicidad de necesidades no satisfechas, por parte de los pacientes de cáncer, sus cuidadores y profesionales de salud asociados. Las recomendaciones hechas por los participantes en el estudio y los autores, siguieron al pie de la letra los lineamientos trazados por la Organización Mundial de la Salud (OMS) en su Modelo de Salud Pública de 1990 para la integración del cuidado paliativo en los sistemas de cuidado de salud existentes.

Therapeutic potential of melatonin agonists.

Melatonin, a hormone secreted by the pineal gland, has been successfully employed to improve sleep in both normal patients and insomniacs, and for the treatment of circadian rhythm sleep disorders. Melatonergic MT1 and MT2 receptors exist in high concentrations in the suprachiasmatic nucleus of the hypothalamus and have been shown to be instrumental for the sleep-promoting and circadian rhythm-regulating effects of melatonin. A lack of consistency among reports on the therapeutic efficacy of melatonin has been attributed to differences in melatonin's bioavailability and the short half-life of the hormone. In view of the need for longer acting melatonergic agonists that improve sleep efficiency without causing drug abuse or dependency, ramelteon (Rozerem™, Takeda) was developed. Ramelteon, which acts via MT1/MT2 melatonergic agonism, has been found clinically effective for improving total sleep time and sleep efficiency in insomniacs. Agomelatine (Valdoxan™, Servier) is another MT1/MT2 melatonergic agonist that also displays antagonist activity at 5-HT2C serotonin receptors. Agomelatine has been found effective in treating depression and sleep disorders in patients with major depressive disorder. A slow-release preparation of melatonin (Circadin™, Neurim) has been shown to be effective in treating sleep disorders in the elderly population.