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1.
Am J Physiol Regul Integr Comp Physiol ; 327(5): R486-R496, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39133776

RESUMO

Angiotensin II (ANG II) has been shown to have central nervous system effects. Although tissue renin-angiotensin systems (RAS) have been demonstrated in multiple tissues, the existence of a brain RAS is still a matter of debate. These studies test for angiotensin release from brain slices prepared from adult male Sprague-Dawley rats and male and female renin knock-out rats using Chinese hamster ovary cells modified to express both the angiotensin II type 1 receptor and a fluorescent calcium indicator. Sniffer cells were placed on the slices and calcium transients were measured from those located on or adjacent to the median preoptic nucleus with and without stimulation of the subfornical organ. Bath application of tetrodotoxin (1 µM) significantly attenuated spontaneous events while abolishing evoked sniffer cell activity. Bath application of dl-AP4 (10 µM, glutamatergic antagonist) did not affect either spontaneous or evoked release. Incubating the slices with fluorocitrate to inactive astrocytes did not influence sniffer cell activity in the MnPO. Pharmacological experiments indicate that ANG II release is largely both renin (aliskiren 10 µM) and ACE-1 (captopril 100 µM) dependent. However, experiments with brain slices prepared from male and female Renin knock-out rats suggest that alternative synthetic pathways may exist. Finally, these studies demonstrate that increases in ANG II release are observed following 7 days of chronic intermittent hypoxia. These studies suggest the existence of a tissue-specific RAS in the brain that involves canonical and alternative ANG II synthetic pathways and is upregulated in an animal model of sleep apnea.NEW & NOTEWORTHY These studies used Chinese hamster ovary cells that were cloned to express an angiotensin receptor (At1ra) and a calcium indicator (R-GECO) to detect the release of angiotensin from brain slices containing the lamina terminalis of rats. Some of the experiments use tissue from renin knockout rats. The results support the existence of an angiotensin system in the brain that may involve alternative synthetic pathways and is upregulated by intermittent hypoxia.


Assuntos
Angiotensina II , Cricetulus , Ratos Sprague-Dawley , Sistema Renina-Angiotensina , Animais , Angiotensina II/farmacologia , Masculino , Feminino , Células CHO , Sistema Renina-Angiotensina/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 1 de Angiotensina/genética , Ratos , Hipotálamo/metabolismo , Hipotálamo/efeitos dos fármacos , Renina/metabolismo , Renina/genética , Sinalização do Cálcio/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos
2.
Am J Physiol Regul Integr Comp Physiol ; 326(5): R333-R345, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38406843

RESUMO

Obstructive sleep apnea, a common form of sleep-disordered breathing, is characterized by intermittent cessations of breathing that reduce blood oxygen levels and contribute to the development of hypertension. Hypertension is a major complication of obstructive sleep apnea that elevates the risk of end-organ damage. Premenopausal women have a lower prevalence of obstructive sleep apnea and cardiovascular disease than men and postmenopausal women, suggesting that sex hormones play a role in the pathophysiology of sleep apnea-related hypertension. The lack of protection in men and postmenopausal women implicates estrogen and progesterone as protective agents but testosterone as a permissive agent in sleep apnea-induced hypertension. A better understanding of how sex hormones contribute to the pathophysiology of sleep apnea-induced hypertension is important for future research and possible hormone-based interventions. The effect of sex on the pathophysiology of sleep apnea and associated intermittent hypoxia-induced hypertension is of important consideration in the screening, diagnosis, and treatment of the disease and its cardiovascular complications. This review summarizes our current understanding of the impact of sex hormones on blood pressure regulation in sleep apnea with a focus on sex differences.


Assuntos
Hipertensão , Síndromes da Apneia do Sono , Apneia Obstrutiva do Sono , Humanos , Feminino , Masculino , Síndromes da Apneia do Sono/complicações , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia , Progesterona , Hipóxia/complicações
3.
J Neurophysiol ; 128(6): 1383-1394, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36321700

RESUMO

Chronic intermittent hypoxia (CIH), an animal model of sleep apnea, has been shown to alter the activity of second-order chemoreceptor neurons in the caudal nucleus of the solitary tract (cNTS). Although numerous studies have focused on excitatory plasticity, few studies have explored CIH-induced plasticity impacting inhibitory inputs to NTS neurons, and the roles of GABAergic and glycinergic inputs on heightened cNTS excitability following CIH are unknown. In addition, changes in astrocyte function may play a role in cNTS plasticity responses to CIH. This study tested the effects of a 7-day CIH protocol on miniature inhibitory postsynaptic currents (mIPSCs) in cNTS neurons receiving chemoreceptor afferents. Normoxia-treated rats primarily displayed GABA mIPSCs, whereas CIH-treated rats exhibited a shift toward combined GABA/glycine-mediated mIPSCs. CIH increased glycinergic mIPSC amplitude and area. This shift was not observed in dorsal motor nucleus of the vagus neurons or cNTS cells from females. Immunohistochemistry showed that strengthened glycinergic mIPSCs were associated with increased glycine receptor protein and were dependent on receptor trafficking in CIH-treated rats. In addition, CIH altered astrocyte morphology in the cNTS, and inactivation of astrocytes following CIH reduced glycine receptor-mediated mIPSC frequency and overall mIPSC amplitude. In cNTS, CIH produced changes in glycine signaling that appear to reflect increased trafficking of glycine receptors to the cell membrane. Increased glycine signaling in cNTS associated with CIH also appears to be dependent on astrocytes. Additional studies will be needed to determine how CIH influences glycine receptor expression and astrocyte function in cNTS.NEW & NOTEWORTHY Chronic intermittent hypoxia (CIH) has been used to mimic the hypoxemia associated with sleep apnea and determine how these hypoxemias influence neural function. The nucleus of the solitary tract is the main site for chemoreceptor input to the CNS, but how CIH influences NTS inhibition has not been determined. These studies show that CIH increases glycine-mediated miniature IPSCs through mechanisms that depend on protein trafficking and astrocyte activation.


Assuntos
Síndromes da Apneia do Sono , Núcleo Solitário , Ratos , Animais , Núcleo Solitário/metabolismo , Receptores de Glicina/metabolismo , Ratos Sprague-Dawley , Hipóxia , Glicina/metabolismo , Ácido gama-Aminobutírico/metabolismo , Síndromes da Apneia do Sono/metabolismo , Inibição Neural/fisiologia
4.
Am J Physiol Regul Integr Comp Physiol ; 321(3): R469-R481, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34189959

RESUMO

Chronic intermittent hypoxia (CIH) is associated with diurnal hypertension, increased sympathetic nerve activity (SNA), and increases in circulating angiotensin II (ANG II). In rats, CIH increases angiotensin type 1 (AT1a) receptor expression in the median preoptic nucleus (MnPO), and pharmacological blockade or viral knockdown of this receptor prevents CIH-dependent increases in diurnal blood pressure. The current study investigates the role of AT1a receptor in modulating the activity of MnPO neurons following 7 days of CIH. Male Sprague-Dawley rats received MnPO injections of an adeno-associated virus with an shRNA against the AT1a receptor or a scrambled control. Rats were then exposed to CIH for 8 h a day for 7 days. In vitro, loose patch recordings of spontaneous action potential activity were made from labeled MnPO neurons in response to brief focal application of ANG II or the GABAA receptor agonist muscimol. In addition, MnPO K-Cl cotransporter isoform 2 (KCC2) protein expression was assessed using Western blot. CIH impaired the duration but not the magnitude of ANG II-mediated excitation in the MnPO. Both CIH and AT1a knockdown also impaired GABAA-mediated inhibition, and CIH with AT1a knockdown produced GABAA-mediated excitation. Recordings using the ratiometric Cl- indicator ClopHensorN showed CIH was associated with Cl- efflux in MnPO neurons that was associated with decreased KCC2 phosphorylation. The combination of CIH and AT1a knockdown attenuated reduced KCC2 phosphorylation seen with CIH alone. The current study shows that CIH, through the activity of AT1a receptors, can impair GABAA-mediated inhibition in the MnPO and contribute to sustained hypertension.


Assuntos
Pressão Sanguínea , Neurônios GABAérgicos/metabolismo , Hipertensão/metabolismo , Hipóxia/metabolismo , Inibição Neural , Área Pré-Óptica/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Receptores de GABA-A/metabolismo , Síndromes da Apneia do Sono/metabolismo , Animais , Doença Crônica , Modelos Animais de Doenças , Hipertensão/genética , Hipertensão/fisiopatologia , Hipóxia/genética , Hipóxia/fisiopatologia , Masculino , Fosforilação , Área Pré-Óptica/fisiopatologia , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina/genética , Síndromes da Apneia do Sono/genética , Síndromes da Apneia do Sono/fisiopatologia , Simportadores/metabolismo , Fatores de Tempo
5.
Am J Physiol Regul Integr Comp Physiol ; 320(4): R519-R525, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33595364

RESUMO

Sleep apnea is characterized by momentary interruptions in normal respiration and leads to periods of decreased oxygen, or intermittent hypoxia. Chronic intermittent hypoxia is a model of the hypoxemia associated with sleep apnea and results in a sustained hypertension that is maintained during normoxia. Adaptations of the carotid body and activation of the renin-angiotensin system may contribute to the development of hypertension associated with chronic intermittent hypoxia. The subsequent activation of the brain renin-angiotensin system may produce changes in sympathetic regulatory neural networks that support the maintenance of the hypertension associated with intermittent hypoxia. Hypertension and sleep apnea not only increase risk for cardiovascular disease but are also risk factors for cognitive decline and Alzheimer's disease. Activation of the angiotensin system could be a common mechanism that links these disorders.


Assuntos
Angiotensina II/metabolismo , Pressão Sanguínea , Cognição , Disfunção Cognitiva/etiologia , Hipertensão/etiologia , Hipóxia/etiologia , Sistema Renina-Angiotensina , Síndromes da Apneia do Sono/complicações , Animais , Doença Crônica , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Humanos , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Fatores de Risco , Transdução de Sinais , Síndromes da Apneia do Sono/metabolismo , Síndromes da Apneia do Sono/fisiopatologia
6.
J Neurophysiol ; 124(2): 591-609, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32697679

RESUMO

Designer receptors exclusively activated by designer drugs (DREADDs) modify cellular activity following administration of the exogenous ligand clozapine-N-oxide (CNO). However, some reports indicate CNO may have off-target effects. The current studies investigate the use of Gq DREADDs in CaMKIIa-expressing neurons in the median preoptic nucleus (MnPO). Male Sprague-Dawley rats (250 g) anesthetized with isoflurane were stereotaxically microinjected in the MnPO with the Gq DREADD (AAV5-CaMKIIa-HM3D-mCherry) or control virus (AAV5-CaMKIIa-mCherry). Following a 2-wk recovery, rats were used for either immunohistochemical Fos analysis or in vitro patch-clamp electrophysiology. In Gq DREADD-injected rats, CNO induced significant increases in Fos staining in the MnPO and in regions that receive direct or indirect projections from the MnPO. In electrophysiological studies, CNO depolarized and augmented firing frequency in both Gq DREADD-positive neurons (Gq DREADD) as well as unlabeled MnPO neurons in slices from Gq DREADD-injected rats (Gq DREADDx). Gq DREADDx neurons also displayed increases in spontaneous postsynaptic current (sPSC) frequency in response to CNO. Additionally, CaMKIIa-positive MnPO neurons, which also express nitric oxide synthase (NOS), were treated with Nω-nitro-l-arginine (l-NNA; competitive inhibitor of NOS) and hemoglobin (NO scavenger) to assess the role of NO in Gq DREADDx neuron recruitment. Both l-NNA and hemoglobin blocked CNO-induced effects in Gq DREADDx neurons without affecting Gq DREADD neurons. These findings indicate that Gq DREADD-mediated activation of CaMKIIa/NOS expressing neurons in the MnPO can influence the activity of neighboring neurons. Future studies utilizing the use of Gq DREADDs will need to consider the potential recruitment of additional cell populations.NEW & NOTEWORTHY Rats were injected in the median preoptic nucleus (MnPO) with either an adeno-associated virus (AAV) and excitatory (Gq) designer receptor exclusively activated by designer drugs (DREADD) construct or a control AAV. In the Gq DREADD-injected rats only, clozapine-N-oxide (CNO) increased Fos staining in the MnPO and its targets and increased neuron action potential frequency. In electrophysiology experiments with slices with DREADD cells, unlabeled cells were activated and this was likely due to nitric oxide release by the DREADD cells.


Assuntos
Potenciais de Ação/fisiologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico/metabolismo , Área Pré-Óptica/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Dependovirus , Drogas Desenhadas , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Masculino , Ratos Sprague-Dawley
7.
Am J Physiol Regul Integr Comp Physiol ; 316(5): R651-R665, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30892911

RESUMO

Chronic intermittent hypoxia (CIH) is a model of the hypoxemia from sleep apnea that causes a sustained increase in blood pressure. Inhibition of the central renin-angiotensin system or FosB in the median preoptic nucleus (MnPO) prevents the sustained hypertensive response to CIH. We tested the hypothesis that angiotensin type 1a (AT1a) receptors in the MnPO, which are upregulated by CIH, contribute to this hypertension. In preliminary experiments, retrograde tract tracing studies showed AT1a receptor expression in MnPO neurons projecting to the paraventricular nucleus. Adult male rats were exposed to 7 days of intermittent hypoxia (cycling between 21% and 10% O2 every 6 min, 8 h/day during light phase). Seven days of CIH was associated with a FosB-dependent increase in AT1a receptor mRNA without changes in the permeability of the blood-brain barrier in the MnPO. Separate groups of rats were injected in the MnPO with an adeno-associated virus containing short hairpin (sh)RNA against AT1a receptors to test their role in intermittent hypoxia hypertension. Injections of shRNA against AT1a in MnPO blocked the increase in mRNA associated with CIH, prevented the sustained component of the hypertension during normoxia, and reduced circulating advanced oxidation protein products, an indicator of oxidative stress. Rats injected with shRNA against AT1a and exposed to CIH had less FosB staining in MnPO and the rostral ventrolateral medulla after intermittent hypoxia than rats injected with the control vector that were exposed to CIH. Our results indicate AT1a receptors in the MnPO contribute to the sustained blood pressure increase to intermittent hypoxia.


Assuntos
Pressão Sanguínea , Hipertensão/etiologia , Hipóxia/complicações , Área Pré-Óptica/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Angiotensina II/administração & dosagem , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Hipertensão/genética , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Hipóxia/genética , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Injeções Intraventriculares , Masculino , Estresse Oxidativo , Área Pré-Óptica/efeitos dos fármacos , Área Pré-Óptica/fisiopatologia , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina/agonistas , Receptor Tipo 1 de Angiotensina/genética , Transdução de Sinais , Regulação para Cima
8.
Am J Physiol Regul Integr Comp Physiol ; 315(5): R972-R982, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30156863

RESUMO

The median preoptic nucleus (MnPO) is an integrative site involved in body fluid homeostasis, cardiovascular control, thermoregulation, and sleep homeostasis. Angiotensin II (ANG II), a neuropeptide shown to have excitatory effects on MnPO neurons, is of particular interest with regard to its role in body fluid homeostasis and cardiovascular control. The present study investigated the role of angiotensin type 1a (AT1a) receptor activation on neuronal excitability in the MnPO. Male Sprague-Dawley rats were infused with an adeno-associated virus with an shRNA against the AT1a receptor or a scrambled control. In vitro loose-patch voltage-clamp recordings of spontaneous action potential activity were made from labeled MnPO neurons in response to brief focal application of ANG II or the GABAA receptor agonist muscimol. Additionally, tissue punches from MnPO were taken to asses mRNA and protein expression. AT1a receptor knockdown neurons were insensitive to ANG II and showed a marked reduction in GABAA-mediated inhibition. The reduction in GABAA-mediated inhibition was not associated with reductions in mRNA or protein expression of GABAA ß-subunits. Knockdown of the AT1a receptor was associated with a reduction in the potassium-chloride cotransporter KCC2 mRNA as well as a reduction in pS940 KCC2 protein. The impaired GABAA-mediated inhibition in AT1a knockdown neurons was recovered by bath application of phospholipase C and protein kinase C activators. The following study indicates that AT1a receptor activation mediates the excitability of MnPO neurons, in part, through the regulation of KCC2. The regulation of KCC2 influences the intracellular [Cl-] and the subsequent efficacy of GABAA-mediated currents.


Assuntos
Agonistas de Receptores de GABA-A/farmacologia , Receptor Tipo 1 de Angiotensina/efeitos dos fármacos , Receptores de GABA-A/efeitos dos fármacos , Simportadores/metabolismo , Potenciais de Ação/fisiologia , Animais , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Área Pré-Óptica/efeitos dos fármacos , Ratos Sprague-Dawley , Receptores de GABA-A/metabolismo , Cotransportadores de K e Cl-
9.
J Neurooncol ; 137(3): 481-492, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29396807

RESUMO

Glioblastoma is a highly malignant disease in critical need of expanded treatment options. The AURKA inhibitor alisertib exhibits antiproliferative activity against glioblastoma in vitro and in vivo. Unlike current clinically used taxane drugs, the novel taxane TPI 287 penetrates the CNS. We tested for interactions between three selective AURKA inhibitors and TPI 287 against standard U87 and U1242 cells and primary glioblastoma neurospheres using colony formation assays. Bliss and Chou-Talalay analyses were utilized to statistically test for synergism. Morphological analysis, flow cytometry and annexin V binding were employed to examine cell cycle and apoptotic effects of these drug combinations. TPI 287 not only potentiated the cytotoxicity of the AURKA inhibitors alisertib, MLN8054 and TC-A2317, but was often potently synergistic. Morphologic and biochemical analysis of the combined effects of alisertib and TPI 287 consistently revealed synergistic induction of apoptosis. While each agent alone induces a mitotic block, slippage occurs allowing some tumor cells to avoid apoptosis. Combination treatment greatly attenuated mitotic slippage, committing the majority of cells to apoptosis. Alisertib and TPI 287 demonstrate significant synergism against glioblastoma cells largely attributable to a synergistic effect in inducing apoptosis. These results provide compelling rationale for clinical testing of alisertib and/or other AURKA inhibitors for potential combination use with TPI 287 against glioblastoma and other CNS neoplasms.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Aurora Quinase A/antagonistas & inibidores , Azepinas/farmacologia , Glioblastoma/tratamento farmacológico , Pirimidinas/farmacologia , Taxoides/farmacologia , Apoptose/fisiologia , Aurora Quinase A/metabolismo , Benzazepinas/farmacologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Glioblastoma/enzimologia , Glioblastoma/patologia , Humanos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Neoplásicas/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Ensaio Tumoral de Célula-Tronco
10.
J Allergy Clin Immunol ; 139(2): 597-606.e4, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27555459

RESUMO

BACKGROUND: Activated phosphoinositide 3-kinase δ syndrome (APDS) is a recently described combined immunodeficiency resulting from gain-of-function mutations in PIK3CD, the gene encoding the catalytic subunit of phosphoinositide 3-kinase δ (PI3Kδ). OBJECTIVE: We sought to review the clinical, immunologic, histopathologic, and radiologic features of APDS in a large genetically defined international cohort. METHODS: We applied a clinical questionnaire and performed review of medical notes, radiology, histopathology, and laboratory investigations of 53 patients with APDS. RESULTS: Recurrent sinopulmonary infections (98%) and nonneoplastic lymphoproliferation (75%) were common, often from childhood. Other significant complications included herpesvirus infections (49%), autoinflammatory disease (34%), and lymphoma (13%). Unexpectedly, neurodevelopmental delay occurred in 19% of the cohort, suggesting a role for PI3Kδ in the central nervous system; consistent with this, PI3Kδ is broadly expressed in the developing murine central nervous system. Thoracic imaging revealed high rates of mosaic attenuation (90%) and bronchiectasis (60%). Increased IgM levels (78%), IgG deficiency (43%), and CD4 lymphopenia (84%) were significant immunologic features. No immunologic marker reliably predicted clinical severity, which ranged from asymptomatic to death in early childhood. The majority of patients received immunoglobulin replacement and antibiotic prophylaxis, and 5 patients underwent hematopoietic stem cell transplantation. Five patients died from complications of APDS. CONCLUSION: APDS is a combined immunodeficiency with multiple clinical manifestations, many with incomplete penetrance and others with variable expressivity. The severity of complications in some patients supports consideration of hematopoietic stem cell transplantation for severe childhood disease. Clinical trials of selective PI3Kδ inhibitors offer new prospects for APDS treatment.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/genética , Síndromes de Imunodeficiência/genética , Transtornos Linfoproliferativos/genética , Mutação/genética , Infecções Respiratórias/genética , Adolescente , Adulto , Animais , Antibioticoprofilaxia , Criança , Pré-Escolar , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Estudos de Coortes , Inibidores Enzimáticos/uso terapêutico , Feminino , Transplante de Células-Tronco Hematopoéticas , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/mortalidade , Infecções por Herpesviridae/terapia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Síndromes de Imunodeficiência/mortalidade , Síndromes de Imunodeficiência/terapia , Lactente , Cooperação Internacional , Transtornos Linfoproliferativos/mortalidade , Transtornos Linfoproliferativos/terapia , Masculino , Camundongos , Pessoa de Meia-Idade , Recidiva , Infecções Respiratórias/mortalidade , Infecções Respiratórias/terapia , Inquéritos e Questionários , Análise de Sobrevida , Adulto Jovem
11.
Psychol Sci ; 28(8): 1067-1076, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28635378

RESUMO

People with autism spectrum conditions (ASC) show reduced sensitivity to contextual stimuli in many perceptual and cognitive tasks. We investigated whether this also applies to decision making by examining adult participants' choices between pairs of consumer products that were presented with a third, less desirable "decoy" option. Participants' preferences between the items in a given pair frequently switched when the third item in the set was changed, but this tendency was reduced among individuals with ASC, which indicated that their choices were more consistent and conventionally rational than those of control participants. A comparison of people who were drawn from the general population and who varied in their levels of autistic traits revealed a weaker version of the same effect. The reduced context sensitivity was not due to differences in noisy responding, and although the ASC group took longer to make their decisions, this did not account for the enhanced consistency of their choices. The results extend the characterization of autistic cognition as relatively context insensitive to a new domain, and have practical implications for socioeconomic behavior.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Tomada de Decisões/fisiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Pediatr Diabetes ; 15(5): 372-83, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24279611

RESUMO

OBJECTIVES: To explore the association between HbA1c 6 months after diagnosis (6 m-HbA1c) and long-term glycaemic control in children with type 1 diabetes, accounting for other bio-psychosocial determinants. METHODS: This retrospective cohort study, included 155 children (≤16 yr) from the North of Scotland, diagnosed between January 1993 and August 2011, and receiving care between November 2008 and August 2012. Multilevel analysis explored the relationships between 6 m-HbA1c, other persistent or dynamic variables, and HbA1c. Patterns of glycaemic control were identified by cluster-analysis. RESULTS: 6 m-HbA1c was positively associated with diabetic ketoacidosis at diagnosis, shorter duration of partial-remission, female gender, and psychosocial adversity. In multilevel analysis the effects of 6 m-HbA1c on subsequent HbA1c trajectories remained significant after adjusting for patient- and observation-level predictors. An increase in 6 m-HbA1c of 10 mmol/mol (0.9%) was associated with an average increase in HbA1c levels of 5.3 (95% CI: 4.5-6.2) mmol/mol, or 0.48% (0.41 to 0.57%; p < 0.001) over the follow-up period. Coefficients for linear and quadratic growth identified sustained effects of 6 m-HbA1c on glycaemic control (p < 0.001). Higher average levels or accelerated increases in HbA1c were associated with age at diagnosis, falling BMI (in girls > boys), mental health diagnosis, major adverse life-events, single-parenting, child welfare concerns, neighbourhood deprivation, and clinic non-attendance. Cluster-analysis identified groups with poor or deteriorating control, characterized by older age at diagnosis, multiple psychosocial adversities, and maladaptive healthcare use. CONCLUSION: Early HbA1c predicted future glycaemic control across childhood. Trajectories were further modified by biological factors, exposures to psychosocial adversity, and healthcare use.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hemoglobinas Glicadas/metabolismo , Carência Psicossocial , Adolescente , Criança , Estudos de Coortes , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/psicologia , Feminino , Humanos , Masculino , Análise Multinível , Estudos Retrospectivos , Escócia/epidemiologia
13.
Healthcare (Basel) ; 12(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38610194

RESUMO

Video gamers can play to negate the psychological impact of stress, which may become problematic when users over-rely on the stress relief potential of gaming. This study used a repeated measures experimental design to investigate the relationships between stress, video gaming, and problematic video gaming behaviours in a convenience sample of 40 students at a UK university. The results indicated that positive affect increased and negative affect decreased, whilst a biological stress measure (instantaneous pulse rate) also decreased after a short video gaming session (t(36) = 4.82, p < 0.001, d = 0.79). The results also suggested that video gaming can act as a short-term buffer against the physiological impact of stress. Further research should focus on testing individuals who have been tested for gaming disorder, as opposed to the general population. Research could also utilise variations of the methodological framework used in this study to examine the intensity of a stress relief effect under different social situations. The study's findings in relation to published works are also discussed.

14.
Neurooncol Adv ; 6(1): vdae009, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327681

RESUMO

Background: Recurrent glioblastoma (rGBM) has limited treatment options. This phase 1 protocol was designed to study the safety and preliminary efficacy of TPI 287, a central nervous system penetrant microtubule stabilizer, in combination with bevacizumab (BEV) for the treatment of rGBM. Methods: GBM patients with up to 2 prior relapses without prior exposure to anti-angiogenic therapy were eligible. A standard 3 + 3 design was utilized to determine the maximum tolerated dose (MTD) of TPI 287. Cohorts received TPI 287 at 140-220 mg/m2 every 3 weeks and BEV 10 mg/kg every 2 weeks during 6-week cycles. An MRI was performed after each cycle, and treatment continued until progression as determined via response assessment in neuro-oncology criteria. Results: Twenty-four patients were enrolled at 6 centers. Treatment was generally well tolerated. Fatigue, myelosuppression, and peripheral neuropathy were the most common treatment emergent adverse events. Dose-limiting toxicity was not observed, thus the MTD was not determined. Twenty-three patients were evaluable for median and 6-month progression-free survival, which were 5.5 months (mo) and 40%, respectively. Median and 12-month overall survival were 13.4 mo and 64%, respectively. The optimal phase 2 dose was determined to be 200 mg/m2. Conclusions: TPI 287 can be safely combined with BEV for the treatment of rGBM and preliminary efficacy supports further investigation of this combination.

15.
Glob Health Action ; 17(1): 2325726, 2024 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-38577879

RESUMO

Increasing evidence suggests that urban health objectives are best achieved through a multisectoral approach. This approach requires multiple sectors to consider health and well-being as a central aspect of their policy development and implementation, recognising that numerous determinants of health lie outside (or beyond the confines of) the health sector. However, collaboration across sectors remains scarce and multisectoral interventions to support health are lacking in Africa. To address this gap in research, we conducted a mixed-method systematic review of multisectoral interventions aimed at enhancing health, with a particular focus on non-communicable diseases in urban African settings. Africa is the world's fastest urbanising region, making it a critical context in which to examine the impact of multisectoral approaches to improve health. This systematic review provides a valuable overview of current knowledge on multisectoral urban health interventions and enables the identification of existing knowledge gaps, and consequently, avenues for future research. We searched four academic databases (PubMed, Scopus, Web of Science, Global Health) for evidence dated 1989-2019 and identified grey literature from expert input. We identified 53 articles (17 quantitative, 20 qualitative, 12 mixed methods) involving collaborations across 22 sectors and 16 African countries. The principle guiding the majority of the multisectoral interventions was community health equity (39.6%), followed by healthy cities and healthy urban governance principles (32.1%). Targeted health outcomes were diverse, spanning behaviour, environmental and active participation from communities. With only 2% of all studies focusing on health equity as an outcome and with 47% of studies published by first authors located outside Africa, this review underlines the need for future research to prioritise equity both in terms of research outcomes and processes. A synthesised framework of seven interconnected components showcases an ecosystem on multisectoral interventions for urban health that can be examined in the future research in African urban settings that can benefit the health of people and the planet.Paper ContextMain findings: Multisectoral interventions were identified in 27.8% of African countries in the African Union, targeted at major cities with five sectors present at all intervention stages: academia or research, agriculture, government, health, and non-governmental.Added knowledge: We propose a synthesised framework showcasing an ecosystem on multisectoral interventions for urban health that can guide future research in African urban settings.Global health impact for policy and action: This study reveals a crucial gap in evidence on evaluating the long-term impact of multisectoral interventions and calls for partnerships involving various sectors and robust community engagement to effectively deliver and sustain health-promoting policies and actions.


Assuntos
Saúde da População Urbana , Humanos , África , Cidades , Política de Saúde
16.
J Neuroendocrinol ; 35(6): e13312, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37337093

RESUMO

Dilutional hyponatremia due to increased plasma arginine vasopressin (AVP) is associated with liver cirrhosis. However, plasma AVP remains elevated despite progressive hypoosmolality. This study investigated changes to inhibitory control of supraoptic nucleus (SON) AVP neurons during liver cirrhosis. Experiments were conducted with adult male Sprague-Dawley rats. Bile duct ligation was used as a model of chronic liver cirrhosis. An adeno-associated virus containing a construct with an AVP promoter and either green fluorescent protein (GFP) or a ratiometric chloride indicator, ClopHensorN, was bilaterally injected into the SON of rats. After 2 weeks, rats received either BDL or sham surgery, and liver cirrhosis was allowed to develop for 4 weeks. In vitro, loose patch recordings of action potentials were obtained from GFP-labeled and unlabeled SON neurons in response to a brief focal application of the GABAA agonist muscimol (100 µM). Changes to intracellular chloride ([Cl]i) following muscimol application were determined by changes to the fluorescence ratio of ClopHensorN. The contribution of cation chloride cotransporters NKCC1 and KCC2 to changes in intracellular chloride was investigated using their respective antagonists, bumetanide (BU, 10 µM) and VU0240551 (10 µM). Plasma osmolality and hematocrit were measured as a marker of dilutional hyponatremia. The results showed reduced or absent GABAA -mediated inhibition in a greater proportion of AVP neurons from BDL rats as compared to sham rats (100% inhibition in sham vs. 47% in BDL, p = .001). Muscimol application was associated with increased [Cl]i in most cells from BDL as compared to cells from sham rats (χ2 = 30.24, p < .001). NKCC1 contributed to the impaired inhibition observed in BDL rats (p < .001 BDL - BU vs. BDL + BU). The results show that impaired inhibition of SON AVP neurons and increased intracellular chloride contribute to the sustained dilutional hyponatremia in liver cirrhosis.


Assuntos
Hiponatremia , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Hiponatremia/metabolismo , Hiponatremia/patologia , Cloretos/metabolismo , Cloretos/farmacologia , Muscimol/metabolismo , Muscimol/farmacologia , Vasopressinas/metabolismo , Arginina Vasopressina/metabolismo , Neurônios/metabolismo , Núcleo Supraóptico/metabolismo , Ductos Biliares/cirurgia , Ductos Biliares/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Proteínas de Fluorescência Verde/metabolismo , Ácido gama-Aminobutírico/metabolismo
17.
Hippocampus ; 22(8): 1703-19, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22367983

RESUMO

Hippocampal pyramidal neurons in vitro exhibit transient learning-dependent reductions in the amplitude and duration of calcium-dependent postburst afterhyperpolarizations (AHPs), accompanied by other increases in excitability (i.e., increased firing rate, or reduced spike-frequency accommodation) after trace eyeblink conditioning or spatial learning, with a time-course appropriate to support consolidation of the learned tasks. Both these tasks require multiple days of training for acquisition. The hippocampus also plays a role in acquisition of single trial inhibitory avoidance learning. The current study assessed AHP plasticity in this single-trial learning task using in vitro tissue slices prepared at varying intervals posttrial using intracellular current-clamp recordings. Reduced AHPs and reduced accommodation were seen in ventral CA1 pyramidal neurons within 1 h posttraining, plasticity which persisted 24 h but was extinguished >72 h posttrial. There was also a reduction in ventral CA1 AHPs and accommodation 1 h following simple exposure to the IA apparatus (a novel context) but this change was extinguished by 24 h postexposure. Reductions in AHPs and accommodation were also seen in dorsal CA1 pyramidal neurons, but were delayed until 24 h posttrial and extinguished at >72 h posttrial. Finally, transient inactivation of the basolateral complex of the amygdala (with the local anesthetics lidocaine or bupivacaine) either immediately before or immediately posttrial blocked both learning and learning-dependent changes in excitability in the hippocampus assessed 24 h posttrial. CA3 pyramidal neurons showed no reductions in AHP peak amplitude or accommodation following IA training or context exposure.


Assuntos
Potenciais de Ação/fisiologia , Tonsila do Cerebelo/fisiologia , Aprendizagem da Esquiva/fisiologia , Região CA1 Hipocampal/metabolismo , Plasticidade Neuronal , Células Piramidais/metabolismo , Análise de Variância , Animais , Piscadela/fisiologia , Região CA3 Hipocampal/metabolismo , Condicionamento Clássico/fisiologia , Masculino , Ratos , Ratos Long-Evans , Fatores de Tempo
18.
J Psychopathol Clin Sci ; 131(4): 392-406, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35357846

RESUMO

Following the popularity of dual process models in social and cognitive psychology, there is major interest in the possibility that autism is associated with impaired "fast" intuitive thinking but enhanced "slow" or "rational" deliberative thinking. If correct, this has great potential to help understand various strengths and difficulties characteristic of autism. Previous empirical investigations of this phenomenon, however, are marred by concerns about the measurement of intuitive and deliberative processing, as well as broader problems in clinical psychological science (e.g., small underpowered studies, lack of replication). Making a step change, we conducted four large-scale studies to examine dual processing in autism, including a preregistered comparison of 200 autistic and nonautistic adults. Participants completed contemporary cognitive and self-report measures of intuitive and deliberative processing, as well as a psychometrically robust measure of general cognitive ability. Except for lower self-reported intuitive thinking, we found no unique contributions of autism to intuitive or deliberative thinking across all four studies, as evidenced by frequentist and Bayesian analyses. Overall, these studies indicate that intuitive and deliberative thinking is neither enhanced nor particularly impaired in relation to autism. We deliberate on the implications of these findings for theories of autism and future investigation of strengths and difficulties in autistic people. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Transtorno Autístico , Processos Mentais , Adulto , Transtorno Autístico/complicações , Transtorno Autístico/psicologia , Teorema de Bayes , Humanos , Processos Mentais/fisiologia , Autorrelato
19.
Cancer Med ; 10(15): 5141-5153, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34152085

RESUMO

OBJECTIVES: To develop a new interface for the widely used prognostic breast cancer tool: Predict: Breast Cancer. To facilitate decision-making around post-surgery breast cancer treatments. To derive recommendations for communicating the outputs of prognostic models to patients and their clinicians. METHOD: We employed a user-centred design process comprised of background research and iterative testing of prototypes with clinicians and patients. Methods included surveys, focus groups and usability testing. RESULTS: The updated interface now caters to the needs of a wider audience through the addition of new visualisations, instantaneous updating of results, enhanced explanatory information and the addition of new predictors and outputs. A programme of future research was identified and is now underway, including the provision of quantitative data on the adverse effects of adjuvant breast cancer treatments. Based on our user-centred design process, we identify six recommendations for communicating the outputs of prognostic models including the need to contextualise statistics, identify and address gaps in knowledge, and the critical importance of engaging with prospective users when designing communications. CONCLUSIONS: For prognostic algorithms to fulfil their potential to assist with decision-making they need carefully designed interfaces. User-centred design puts patients and clinicians needs at the forefront, allowing them to derive the maximum benefit from prognostic models.


Assuntos
Neoplasias da Mama/terapia , Tomada de Decisão Clínica , Intervenção Baseada em Internet , Cuidados Pós-Operatórios , Interface Usuário-Computador , Adulto , Neoplasias da Mama/cirurgia , Gráficos por Computador , Gerenciamento Clínico , Feminino , Grupos Focais , Humanos , Prognóstico , Medição de Risco , Inquéritos e Questionários , Design Centrado no Usuário
20.
Endocrinology ; 162(8)2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33891015

RESUMO

Arginine vasopressin (AVP) and oxytocin (OXY) are released by magnocellular neurosecretory cells that project to the posterior pituitary. While AVP and OXY currently receive more attention for their contributions to affiliative behavior, this mini-review discusses their roles in cardiovascular function broadly defined to include indirect effects that influence cardiovascular function. The traditional view is that neither AVP nor OXY contributes to basal cardiovascular function, although some recent studies suggest that this position might be re-evaluated. More evidence indicates that adaptations and neuroplasticity of AVP and OXY neurons contribute to cardiovascular pathophysiology.


Assuntos
Arginina Vasopressina/fisiologia , Pressão Sanguínea , Sistema Cardiovascular/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Ocitocina/fisiologia , Animais , Volume Sanguíneo , Doenças Cardiovasculares/etiologia , Humanos , Natriurese , Receptores de Ocitocina/metabolismo , Receptores de Vasopressinas/metabolismo , Caracteres Sexuais
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