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1.
Appl Opt ; 63(16): 4366-4371, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856615

RESUMO

We present the retrieval of depth-resolved temperature measurements in water using Raman LiDAR. Using a 5 m pipe of laboratory water, we recover non-homogeneous temperature profiles with a temperature accuracy ranging between 0.35°C and 0.85°C, and a position resolution of 28 cm.

2.
Health Qual Life Outcomes ; 17(1): 30, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30732633

RESUMO

BACKGROUND: Daytime sleepiness is highly prevalent across the globe. The Epworth sleepiness scale (ESS) is the most widely used tool for screening daytime sleepiness. The psychometric properties of the ESS have not been comprehensively examined in African populations. MATERIAL AND METHODS: A cross-sectional design with simple random sampling was used in the present study. The study recruited 600 students from Mizan-Tepi University, Ethiopia, of which 329 (age = 18-28 years and body mass index = 21.19 ± 3.17 kg/m2) completed the study. ESS, a semi-structured socio-demographics questionnaire and a clinical interview to diagnose insomnia according to the International Classification of Sleep Disorders were employed. RESULTS: All except one item of the ESS showed a floor effect, while only one item score showed ceiling effect. However, no ceiling/floor effect was observed in the ESS total score. The Cronbach's alpha (0.75) and composite reliability (0.75), indicated good internal consistency, while a moderate item-total score correlation (r = 0.55-0.67) implied favorable internal homogeneity. The known-group validity was established by significantly higher scores for all the ESS item scores and the ESS total scores among those with symptoms of insomnia than among non-symptomatic students. Fit indices along with the consideration of inter-factor correlation coefficient, measures of item retention favored the unidimensional structure of the ESS. CONCLUSION: The ESS has excellent psychometric validity for screening daytime sleepiness in Ethiopian university students.


Assuntos
Transtornos do Sono-Vigília/diagnóstico , Sonolência , Inquéritos e Questionários/normas , Adulto , Estudos Transversais , Etiópia , Feminino , Humanos , Masculino , Psicometria/estatística & dados numéricos , Qualidade de Vida , Reprodutibilidade dos Testes , Estudantes/psicologia , Universidades , Adulto Jovem
3.
Int J Obes (Lond) ; 38(4): 577-90, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23892523

RESUMO

Pregnancy and the postpartum period is a time of increased vulnerability for retention of excess body fat in women. Breastfeeding (BF) has been shown to have many health benefits for both mother and baby; however, its role in postpartum weight management is unclear. Our aim was to systematically review and critically appraise the literature published to date in relation to the impact of BF on postpartum weight change, weight retention and maternal body composition. Electronic literature searches were carried out using MEDLINE, EMBASE, PubMed, Web of Science, BIOSIS, CINAHL and British Nursing Index. The search covered publications up to 12 June 2012 and included observational studies (prospective and retrospective) carried out in BF mothers (either exclusively or as a subgroup), who were ≤ 2 years postpartum and with a body mass index (BMI) >18.5 kg m(-2), with an outcome measure of change in weight (including weight retention) and/or body composition. Thirty-seven prospective studies and eight retrospective studies were identified that met the selection criteria; studies were stratified according to study design and outcome measure. Overall, studies were heterogeneous, particularly in relation to sample size, measurement time points and in the classification of BF and postpartum weight change. The majority of studies reported little or no association between BF and weight change (n=27, 63%) or change in body composition (n=16, 89%), although this seemed to depend on the measurement time points and BF intensity. However, of the five studies that were considered to be of high methodological quality, four studies demonstrated a positive association between BF and weight change. This systematic review highlights the difficulties of examining the association between BF and weight management in observational research. Although the available evidence challenges the widely held belief that BF promotes weight loss, more robust studies are needed to reliably assess the impact of BF on postpartum weight management.


Assuntos
Aleitamento Materno , Obesidade/prevenção & controle , Período Pós-Parto , Redução de Peso , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Gravidez , Saúde da Mulher
4.
Ann Oncol ; 29(8): 1634-1657, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30032243
5.
BJOG ; 120(8): 932-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23530609

RESUMO

OBJECTIVE: To assess the prevalence of overweight and obesity, and the impact of body mass index (BMI) on maternal and neonatal outcomes, in a UK obstetric population. DESIGN: Retrospective study. SETTING: A tertiary referral unit in Northern Ireland. POPULATION: A total of 30 298 singleton pregnancies over an 8-year period, 2004-2011. METHODS: Women were categorised according to World Health Organization classification: underweight (BMI < 18.50 kg/m(2)); normal weight (BMI 18.50-24.99 kg/m(2); reference group); overweight (BMI 25.00-29.99 kg/m(2)); obese class I (BMI 30.00-34.99 kg/m(2)); obese class II (BMI 35-39.99 kg/m(2)); and obese class III (BMI ≥ 40 kg/m(2)). Maternal and neonatal outcomes were examined using logistic regression, adjusted for confounding variables. MAIN OUTCOME MEASURES: Maternal and neonatal outcomes. RESULTS: Compared with women of normal weight, women who were overweight or obese class I were at significantly increased risk of hypertensive disorders of pregnancy (OR 1.9, 99% CI 1.7-2.3; OR 3.5, 99% CI 2.9-4.2); gestational diabetes mellitus (OR 1.7, 99% CI 1.3-2.3; OR 3.7, 99% CI 2.8-5.0); induction of labour (OR 1.2, 99% CI 1.1-1.3; OR 1.3, 99% CI 1.2-1.5); caesarean section (OR 1.4, 99% CI 1.3-1.5; OR 1.8, 99% CI 1.6-2.0); postpartum haemorrhage (OR 1.4, 99% CI 1.3-1.5; OR 1.8, 1.6-2.0); and macrosomia (OR 1.5, 99% CI 1.3-1.6; OR 1.9, 99% CI 1.6-2.2), with the risks increasing for obese classes II and III. Women in obese class III were at increased risk of preterm delivery (OR 1.6, 99% CI 1.1-2.5), stillbirth (OR 3.0, 99% CI 1.0-9.3), postnatal stay > 5 days (OR 2.1, 99% CI 1.5-3.1), and infant requiring admission to a neonatal unit (OR 1.6, 99% CI 1.0-2.6). CONCLUSIONS: By categorising women into overweight and obesity subclassifications (classes I -III), this study clearly demonstrates an increasing risk of adverse outcomes across BMI categories, with women who are overweight also at significant risk.


Assuntos
Obesidade/complicações , Sobrepeso/complicações , Adulto , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Recém-Nascido , Irlanda do Norte , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Gravidez , Resultado da Gravidez , Prevalência , Estudos Retrospectivos , Fatores de Risco
6.
J Econ Entomol ; 106(5): 2093-100, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24224251

RESUMO

Significant mortality ofredbay trees (Persea borbonia (L.) Spreng.) in the southeastern United States has been caused by Raffaelea lauricola, T.C. Harr., Fraedrich, & Aghayeva (Harrington et al. 2008), a fungal symbiont of the exotic redbay ambrosia beetle, Xyleborus glabratus, Eichhoff (Fraedrich et al. 2008). This pathogen causes laurel wilt, which is an irreversible disease that can kill mature trees within a few weeks in summer. R. lauricola has been shown to be lethal to most native species of Lauraceae and cultivated avocado (Persea americana Mill.) in the southeastern United States. In this study, we examined the survival of X. glabratus and R. lauricola in wood chips made from infested trees by using a standard tree chipper over a 10-wk period. After 2 wk, 14 X. glabratus were recovered from wood chips, whereas 339 X. glabratus emerged from nonchipped bolts. R. lauricola was not found 2 d postchipping from wood chips, indicating that the pathogen is not likely to survive for long inside wood chips. In contrast, R. lauricola persisted in dead, standing redbay trees for 14 mo. With large volumes of wood, the potential for infested logs to be moved between states or across U.S. borders is significant. Results demonstrated that chipping wood from laurel wilt-killed trees can significantly reduce the number of X. glabratus and limit the persistence of R. lauricola, which is important for sanitation strategies aimed at limiting the spread of this disease.


Assuntos
Ophiostomatales/fisiologia , Persea/microbiologia , Doenças das Plantas/prevenção & controle , Gorgulhos/microbiologia , Gorgulhos/fisiologia , Animais , Feminino , Florida , Controle de Insetos/métodos , Persea/química , Dinâmica Populacional , Estações do Ano , Árvores/química , Árvores/microbiologia , Madeira/química , Madeira/microbiologia
7.
Eur J Orthop Surg Traumatol ; 23(6): 665-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23412186

RESUMO

AIMS: Recent NHS reforms have incentivised reduction in length of stay, with the UK department of health expecting health trusts to reduce bed days and ultimately reduce overall costs. The aim of this study was to identify avoidable causes for protracted hospital admission following total hip arthroplasty (THA) or total knee arthroplasty (TKA) within a fast-track unit. METHODS: During a 6-month period, 535 consecutive patients underwent primary THA or TKA under the care of a single surgeon. All patients with a post-operative stay of greater than 72 h were identified, and reasons for delayed discharge were determined. RESULTS: The majority of arthroplasty patients were discharged within 3 days post-operatively. Twenty-one per cent of THA patients and 25 % of TKA patients remained as inpatients for greater than 72 h. For the THA population, this equates to 43 % of bed days used by 21 % of patients, and for the TKA population, 44 % of bed days were used by 25 % of patients. The major factor within both groups for delayed discharge was attributed to inadequate social support. CONCLUSIONS: Delayed discharge can never be totally prevented. This unit aims to develop improvement in social work provision, with a greater focus on pre-admission discharge planning to reduce the number of delayed discharges and ultimately reduce the cost burden of joint replacement surgery. It is not conducive with the ethos of fast-track arthroplasty to only identify social circumstances upon admission.


Assuntos
Artroplastia de Quadril/estatística & dados numéricos , Artroplastia do Joelho/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Alta do Paciente/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/economia , Artroplastia do Joelho/economia , Efeitos Psicossociais da Doença , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Resultado do Tratamento
8.
Injury ; 54(10): 110946, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37517375

RESUMO

BACKGROUND: Re-operation following hip hemiarthroplasty is potentially devastating due to a frail, co-morbid surgical cohort. We aimed to assess the outcomes of patients who required early return to theatre (RTT) within 30 days of index operation in a high-volume hip fracture unit. METHODS: A retrospective review of a prospectively maintained database was undertaken. All hip hemiarthroplasties performed between 1st January 2010 and 31st December 2019 was included. Demographic details, complications including reason for return to theatre, length of stay, discharge destination, functional outcome and mortality were collected and reviewed. RESULTS: 4340 hip hemiarthroplasty procedures were performed, of which 64 patients (1.47%) required early RTT within 30 days of index procedure and 4276 patients did not require early-RTT. The most common reasons for RTT were infection (n = 47) and dislocation (n = 15). There were no cases of peri­prosthetic fracture requiring RTT within 30 days. Patients requiring early RTT had a significantly increased rate of mortality within 120 days; 32.8% (21 of the 64 patients) versus 13.6% (580 out of the 4276) not requiring early RTT (p < 0.001). The median length of acute inpatient admission for patients who required early RTT was significantly longer at 31 days (range 6-185 days) compared to 10 days (range 3-171 days, p < 0.001) for those without early RTT. Early RTT was associated with a poorer functional mobility outcome at 120 days post-operatively, with a significantly greater reduction in Barthel score compared to the non-RTT cohort (p < 0.05). CONCLUSION: Patients requiring early RTT following hip hemiarthroplasty had a significantly increased length of stay, mortality and worse functional outcome compared to patients who did not require early RTT within 30 days.


Assuntos
Artroplastia de Quadril , Fraturas do Colo Femoral , Hemiartroplastia , Fraturas do Quadril , Humanos , Fraturas do Colo Femoral/cirurgia , Seguimentos , Hemiartroplastia/efeitos adversos , Fraturas do Quadril/cirurgia , Estudos Retrospectivos , Artroplastia de Quadril/efeitos adversos , Resultado do Tratamento
9.
Opt Lett ; 37(18): 3840-2, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23041877

RESUMO

In this work we explore a method for controlling Raman cascade within an intracavity Raman laser, with a view to maximizing output power at desired visible wavelengths. Sum-frequency generation is used to suppress unwanted Stokes orders, and prevent their build up. Using this method to control the Raman cascade, we demonstrate increases in output power of 40% at 532 nm, 42% at 559 nm, and 67% at 586 nm.

10.
Clin Orthop Relat Res ; 470(7): 1958-65, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22270468

RESUMO

BACKGROUND: Periarticular infiltration of local anesthetic, NSAIDs, and adrenaline have been reported to reduce postoperative pain, improve mobility, and reduce hospital stay for patients having THAs, but available studies have not determined whether local anesthetic infiltration alone achieves similar improvements. QUESTIONS: We therefore asked whether periarticular injection of a local anesthetic during THA reduced postoperative pain and opioid requirements and improved postoperative mobility. METHODS: We randomized 96 patients to either treatment (n = 50) or control groups (n = 46). Before wound closure, the treatment group received local infiltration of 160 mL of levobupivacaine with adrenaline. The control group received no local infiltration. We assessed postoperative morphine consumption and pain during the 24 hours after surgery. Mobilization was assessed 24 hours postoperatively with supine-to-sit and sit-to-stand transfers, timed 10-m walk test, and timed stair ascent and descent. Patients and assessing physiotherapists were blind to study status. RESULT: We observed no differences in postoperative morphine consumption, time to ascend and descend stairs, or ability to transfer between treatment and control groups. The treatment group reported more pain 7 to 12 hours postoperatively, but there were no differences in pain scores between groups at all other postoperative intervals. The treatment group showed increased postoperative walking speed greater than 6 m, but not greater than 10 m, compared with the control group. CONCLUSIONS: Periarticular infiltration of local anesthetic during THA did not reduce postoperative pain or length of hospital stay and did not improve early postoperative mobilization.


Assuntos
Anestésicos Locais/administração & dosagem , Artrite Reumatoide/cirurgia , Articulação do Quadril/cirurgia , Dor Pós-Operatória/prevenção & controle , Agonistas Adrenérgicos/administração & dosagem , Idoso , Analgésicos Opioides/uso terapêutico , Artrite Reumatoide/fisiopatologia , Artroplastia de Quadril/efeitos adversos , Bupivacaína/administração & dosagem , Bupivacaína/análogos & derivados , Distribuição de Qui-Quadrado , Deambulação Precoce , Epinefrina/administração & dosagem , Feminino , Articulação do Quadril/fisiopatologia , Humanos , Tempo de Internação , Levobupivacaína , Masculino , Pessoa de Meia-Idade , Morfina/uso terapêutico , Irlanda do Norte , Medição da Dor , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia , Análise de Componente Principal , Estudos Prospectivos , Recuperação de Função Fisiológica , Fatores de Tempo , Resultado do Tratamento
11.
Public Health ; 126(7): 561-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22607982

RESUMO

OBJECTIVE: To compare blood pressure between 50-year-old adults who were born at term (37-42 weeks of gestation) with intra-uterine growth restriction (IUGR; birth weight <10th centile) and a control group of similar age born at term without IUGR (birth weight ≥10th centile). STUDY DESIGN: Controlled comparative study. METHODS: Participants included 232 men and women who were born at the Royal Maternity Hospital, Belfast, a large regional maternity hospital in Northern Ireland, between 1954 and 1956. One hundred and eight subjects who were born with IUGR were compared with 124 controls with normal birth weight for gestation. The main outcome measures were systolic and diastolic blood pressure at approximately 50 years of age, measured according to European recommendations. RESULTS: The IUGR group had higher systolic and diastolic blood pressure than the control group: 131.5 [95% confidence interval (CI) 127.9-135.1] vs 127.1 (95% CI 124.3-129.2) mmHg and 82.3 (95% CI 79.6-85.0) vs 79.0 (95% CI 77.0-81.0) mmHg, respectively. After adjustment for gender, the differences between the groups were statistically significant: systolic blood pressure 4.5 (95% CI 0.3-8.7) mmHg and diastolic blood pressure 3.4 (95% CI 0.2-6.5) mmHg (both P < 0.05). More participants in the IUGR group were receiving treatment for high blood pressure compared with the control group [16 (15%) vs 11 (9%)], although this was not statistically significant. The proportion of subjects with blood pressure >140/90 mmHg or currently receiving antihypertensive treatment was 45% (n = 49) for the IUGR group, and 31% (n = 38) for the control group (odds ratio 1.9, 95% CI 1.1-3.3). Adjustment for potential confounders made little difference. CONCLUSIONS: IUGR is associated with higher blood pressure at 50 years of age. Individuals born with IUGR should have regular blood pressure screening and early treatment as required. Hypertension remains underdiagnosed and undertreated in adult life.


Assuntos
Retardo do Crescimento Fetal , Hipertensão/epidemiologia , Efeitos Tardios da Exposição Pré-Natal , Pressão Sanguínea , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Irlanda do Norte/epidemiologia , Gravidez , Risco
12.
J Transl Autoimmun ; 5: 100161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36039310

RESUMO

Autoimmune diseases affect over 40 million people in the United States. The cause of most autoimmune diseases is unknown; therefore, most therapies focus on treating the symptoms. This review will focus on the autoimmune diseases type 1 diabetes (T1D) and multiple sclerosis (MS) and the emerging roles of red blood cells (RBCs) in the mechanisms and treatment of T1D and MS. An understanding of the role of the RBC in human health is increasing, especially with respect to its role in the regulation of vascular caliber and vessel dilation. The RBC is known to participate in the regulation of blood flow through the release of key signaling molecules, such as adenosine triphosphate (ATP) and the potent vasodilator nitric oxide (NO). However, while these RBC-derived molecules are known to be determinants of blood flow in vivo, disruptions in their concentrations in the circulation are often measured in common autoimmune diseases. Chemical and physical properties of the RBC may play a role in autoimmune disease onset, especially T1D and MS, and complications associated with downstream extracellular levels of ATP and NO. Finally, both ATP and NO are highly reactive molecules in the circulation. Coupled with the challenging matrix posed by the bloodstream, the measurement of these two species is difficult, thus prompting an appraisal of recent and novel methods to quantitatively determining these potential early indicators of immune response.

13.
ACS Chem Neurosci ; 13(17): 2658-2665, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-35946788

RESUMO

Multiple sclerosis (MS) is an inflammatory disease characterized by damage to the myelin sheath surrounding axons in the central nervous system. While the exact mechanism of this destruction is unknown, excess nitric oxide (NO) and adenosine triphosphate (ATP) have been measured in tissues and fluids obtained from people with MS. Here, incubation of interferon-beta (IFN-ß), an MS drug with an unknown mechanism of action, with red blood cells (RBCs) obtained from people with MS provide evidence of a potential hypermetabolic state in the MS RBC that is decreased with IFN-ß intervention. Specifically, binding of all three components of an albumin/C-peptide/Zn2+ complex to MS RBCs was significantly increased in comparison to control RBCs. For example, the binding of C-peptide to MS RBCs was significantly increased (3.4 ± 0.1 nM) compared to control RBCs (1.6 ± 0.2 nM). However, C-peptide binding to MS RBCs was reduced to a value (1.6 ± 0.3 nM) statistically equal to that of control RBCs in the presence of 2 nM IFN-ß. Similar trends were measured for albumin and Zn2+ binding to RBCs when in the presence of IFN-ß. RBC function was also affected by incubation of cells with IFN-ß. Specifically, RBC-derived ATP and measurable membrane GLUT1 were both significantly decreased (56 and 24%, respectively) in the presence of IFN-ß. Collectively, our results suggest that IFN-ß inhibits albumin binding to the RBC, thereby reducing its ability to deliver ligands such as C-peptide and Zn2+ to the cell and normalizing the basal hypermetabolic state.


Assuntos
Interferon beta , Esclerose Múltipla , Trifosfato de Adenosina/metabolismo , Albuminas/metabolismo , Peptídeo C/metabolismo , Eritrócitos/metabolismo , Humanos , Interferon beta/metabolismo , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/metabolismo
14.
Childs Nerv Syst ; 27(6): 879-91, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21104186

RESUMO

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.


Assuntos
Líquidos Corporais/química , Líquidos Corporais/metabolismo , Melatonina/análise , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/normas , Ritmo Circadiano/fisiologia , Eletroforese Capilar/métodos , Eletroforese Capilar/normas , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/normas , Humanos , Melatonina/análogos & derivados , Melatonina/sangue , Melatonina/metabolismo , Saliva/química , Saliva/metabolismo , Revisões Sistemáticas como Assunto
15.
J Pineal Res ; 49(1): 1-13, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20492443

RESUMO

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.


Assuntos
Glaucoma/tratamento farmacológico , Glaucoma/metabolismo , Melatonina/metabolismo , Fármacos Neuroprotetores/metabolismo , Uveíte/tratamento farmacológico , Uveíte/metabolismo , Animais , Humanos , Melatonina/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Oftalmologia , Receptores de Melatonina/metabolismo
16.
J Pineal Res ; 48(1): 1-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20025640

RESUMO

Malaria, which infects more than 300 million people annually, is a serious disease. Epidemiological surveys indicate that of those who are affected, malaria will claim the lives of more than one million individuals, mostly children. There is evidence that the synchronous maturation of Plasmodium falciparum, the parasite that causes a severe form of malaria in humans and Plasmodium chabaudi, responsible for rodent malaria, could be linked to circadian changes in melatonin concentration. In vitro melatonin stimulates the growth and development of P. falciparum through the activation of specific melatonin receptors coupled to phospholipase-C activation and the concomitant increase of intracellular Ca2+. The Ca2+ signaling pathway is important to stimulate parasite transition from the trophozoite to the schizont stage, the final stage of intraerythrocytic cycle, thus promoting the rise of parasitemia. Either pinealectomy or the administration of the melatonin receptor blocking agent luzindole desynchronizes the parasitic cell cycle. Therefore, the use of melatonin antagonists could be a novel therapeutic approach for controlling the disease. On the other hand, the complexity of melatonin's action in malaria is underscored by the demonstration that treatment with high doses of melatonin is actually beneficial for inhibiting apoptosis and liver damage resulting from the oxidative stress in malaria. The possibility that the coordinated administration of melatonin antagonists (to impair the melatonin signal that synchronizes P. falciparum) and of melatonin in doses high enough to decrease oxidative damage could be a novel approach in malaria treatment is discussed.


Assuntos
Antimaláricos/uso terapêutico , Malária/tratamento farmacológico , Malária/metabolismo , Melatonina/metabolismo , Melatonina/uso terapêutico , Plasmodium falciparum/crescimento & desenvolvimento , Animais , Apoptose/efeitos dos fármacos , Humanos , Melatonina/farmacologia , Modelos Biológicos , Plasmodium falciparum/efeitos dos fármacos , Receptores de Melatonina/antagonistas & inibidores , Triptaminas/uso terapêutico
17.
Prog Neurobiol ; 85(3): 335-53, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18571301

RESUMO

Melatonin, an endogenous signal of darkness, is an important component of the body's internal time-keeping system. As such it regulates major physiological processes including the sleep wake cycle, pubertal development and seasonal adaptation. In addition to its relevant antioxidant activity, melatonin exerts many of its physiological actions by interacting with membrane MT1 and MT2 receptors and intracellular proteins such as quinone reductase 2, calmodulin, calreticulin and tubulin. Here we review the current knowledge about the properties and signaling of melatonin receptors as well as their potential role in health and some diseases. Melatonin MT1 and MT2 receptors are G protein coupled receptors which are expressed in various parts of the CNS (suprachiasmatic nuclei, hippocampus, cerebellar cortex, prefrontal cortex, basal ganglia, substantia nigra, ventral tegmental area, nucleus accumbens and retinal horizontal, amacrine and ganglion cells) and in peripheral organs (blood vessels, mammary gland, gastrointestinal tract, liver, kidney and bladder, ovary, testis, prostate, skin and the immune system). Melatonin receptors mediate a plethora of intracellular effects depending on the cellular milieu. These effects comprise changes in intracellular cyclic nucleotides (cAMP, cGMP) and calcium levels, activation of certain protein kinase C subtypes, intracellular localization of steroid hormone receptors and regulation of G protein signaling proteins. There are circadian variations in melatonin receptors and responses. Alterations in melatonin receptor expression as well as changes in endogenous melatonin production have been shown in circadian rhythm sleep disorders, Alzheimer's and Parkinson's diseases, glaucoma, depressive disorder, breast and prostate cancer, hepatoma and melanoma. This paper reviews the evidence concerning melatonin receptors and signal transduction pathways in various organs. It further considers their relevance to circadian physiology and pathogenesis of certain human diseases, with a focus on the brain, the cardiovascular and immune systems, and cancer.


Assuntos
Melatonina/fisiologia , Receptores de Melatonina/fisiologia , Transdução de Sinais/fisiologia , Animais , Humanos
18.
West Indian Med J ; 59(1): 59-66, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20931916

RESUMO

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.


Assuntos
Necessidades e Demandas de Serviços de Saúde , Neoplasias/diagnóstico , Neoplasias/terapia , Adolescente , Adulto , Comunicação , Estudos Transversais , Demografia , Feminino , Grupos Focais , Humanos , Incidência , Entrevistas como Assunto , Jamaica/epidemiologia , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Relações Médico-Paciente , Inquéritos e Questionários
19.
Sci Rep ; 10(1): 17493, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060722

RESUMO

People with type 1 diabetes (T1D) require exogenous administration of insulin, which stimulates the translocation of the GLUT4 glucose transporter to cell membranes. However, most bloodstream cells contain GLUT1 and are not directly affected by insulin. Here, we report that C-peptide, the 31-amino acid peptide secreted in equal amounts with insulin in vivo, is part of a 3-component complex that affects red blood cell (RBC) membranes. Multiple techniques were used to demonstrate saturable and specific C-peptide binding to RBCs when delivered as part of a complex with albumin. Importantly, when the complex also included Zn2+, a significant increase in cell membrane GLUT1 was measured, thus providing a cellular effect similar to insulin, but on a transporter on which insulin has no effect.


Assuntos
Peptídeo C/administração & dosagem , Eritrócitos/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Soroalbumina Bovina/química , Zinco/administração & dosagem , Trifosfato de Adenosina/química , Animais , Transporte Biológico , Bovinos , Membrana Celular/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Regulação da Expressão Gênica , Glucose/metabolismo , Humanos , Insulina/metabolismo
20.
Healthcare (Basel) ; 8(2)2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272668

RESUMO

Background: Various studies have shown that insomnia is associated with computer use. The Athens Insomnia Scale (AIS) is an 8-item tool that has been widely used for screening insomnia. No studies have investigated the psychometric validity of AIS in occupational computer users. Objective: the current research aimed to test the psychometric properties of the AIS among occupational computer users. Materials and Methods: a sample of four hundred and twenty-four occupational computer users (age: 20-65 years and body mass index: 21.6 ± 3.5 kg/m2) completed an AIS and a socio-demographic questionnaire in this cross-sectional study. Results: a confirmatory factor analysis demonstrated that the three-factor model had an adequate fit (the goodness of fit index (0.95), incremental fit index (0.90) and χ2/df (2.61)). Evidence was found for configural, scalar and metric invariance of the 3-factor model across gender groups. A moderate level of internal consistency was implied by a Cronbach's alpha of 0.66. Conclusion: the findings of the present research support the validity of AIS for screening insomnia, as demonstrated by the scale's psychometric properties; its internal consistency, internal homogeneity, item discrimination, and factorial validity.

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