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1.
Rheumatol Int ; 44(1): 145-156, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37733042

RESUMEN

Life-long exercise is essential in axial spondyloarthritis (axSpA) management; however, long-term adherence is challenging. Online exercise programmes are an alternative to face-to-face physiotherapy. (1) To measure adherence to a 12-month, individualised, online physiotherapy programme for people with axSpA, and investigate the effects on disease activity, spinal mobility, work ability, quality of life and function. (2) To investigate associations between programme adherence and outcomes. (3) To explore participants' views of the programme and factors affecting adherence. Participants were 'non-exercisers' recruited from rheumatology outpatient services. Adherence was measured using online diary entries. Outcomes included the BATH indices, health status (EQ5D), Ankylosing Spondylitis Quality of Life (ASQOL), exercise capacity (6MWT), Work, Productivity and Activity Impairment in AS (WPAI), Exercise Attitude Questionnaire (EAQ) and Exercise Motivations Inventory-2 (EMI-2) at baseline, 6 and 12 months. Interviews determined views on the intervention and factors affecting adherence. Fifty participants were recruited. Over the 52-week intervention, adherence (five times/week) ranged from 19% (± 30%) to 44% (± 35%). Significant improvements were found in disease activity (BASDAI), spinal mobility (BASMI), 6MWT, AsQoL and EQ5D-VAS at 6 and 12 months. There were no associations between adherence and baseline variables or demographics. Interviews suggested support from others, routine, and feeling the benefit positively affected adherence. Conversely, lack of motivation, life events and symptoms negatively affected adherence. A 12-month online physiotherapy programme significantly improved symptoms in people with axSpA who were not regular exercisers. Adherence reduced over the intervention period. Online exercise programmes may benefit people with axSpA; however, strategies to improve adherence are required.


Asunto(s)
Espondiloartritis , Espondilitis Anquilosante , Humanos , Estudios de Cohortes , Calidad de Vida , Modalidades de Fisioterapia , Columna Vertebral , Espondiloartritis/terapia
2.
J Dairy Sci ; 107(3): 1788-1804, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37806631

RESUMEN

The objective was to compare pregnancy per service event (P/S) in lactating dairy cows following timed artificial insemination (AI) or timed embryo transfer (ET) using either fresh or frozen in vitro-produced embryos. Oocytes were collected once per week for up to 9 wk using transvaginal ovum pick-up from elite dairy donors (ET-DAIRY; n = 40; Holstein-Friesian and Jersey) and elite beef donors (ET-ELITE-BEEF; n = 21; Angus). Both ET-DAIRY and ET-ELITE-BEEF donors consisted of heifers and cows. In addition, oocytes were collected from the ovaries of beef heifers of known pedigree following slaughter at a commercial abattoir (ET-COMM-BEEF; n = 119). Following in vitro maturation and fertilization, presumptive zygotes were cultured in vitro to the blastocyst stage. Grade 1 blastocysts were either transferred fresh or frozen for on-farm thawing and direct transfer. A total of 1,106 recipient cows (all lactating, predominantly Holstein-Friesian) located on 16 herdlets were blocked based on parity, calving date, and Economic Breeding Index, and randomly assigned to receive AI (n = 243) or ET (n = 863) after estrous synchronization with a 10-d Progesterone-synch protocol. Cows assigned to ET were further randomized to receive fresh (n = 187) or frozen (n = 178) ET-ELITE-BEEF embryos, fresh (n = 169) or frozen (n = 162) ET-DAIRY embryos, or fresh (n = 80) or frozen (n = 87) ET-COMM-BEEF embryos. Pregnancy was diagnosed using transrectal ultrasound on d 32 to 35 after synchronized ovulation and confirmed on d 62 to 65, at which time fetal sex was determined. Pregnancy per service event at d 32 was not different between AI (48.8%) and ET (48.9%) and did not differ between dairy and beef embryos (50.3% vs. 48.1%, respectively). However, P/S was less on d 32 following transfer of frozen embryos (41.6%) compared with fresh embryos (56.1%). Pregnancy loss between d 32 and 62 was greater for ET (15.1%) compared with AI (4.7%), with greater losses observed for frozen beef (18.5%), fresh beef (17.3%), and frozen dairy (19.2%) compared with fresh dairy (6.0%) embryos. Serum progesterone (P4) concentration on d 7 was associated with P/S at d 32 and 62. Cows in the quartile with the least serum P4 concentrations (quartile 1) had less probability of being pregnant on d 32 (33.4%) compared with cows in the 3 upper quartiles for serum P4 (45.7%, 55.6%, and 61.2% for quartile 2, quartile 3, and quartile 4, respectively). Sex ratio (male:female) at d 62 was skewed toward more male fetuses following ET (61.1:38.9) compared with AI (43.2:56.8) and was consistent with the sex ratio among in vitro blastocysts (61.2:38.8). In conclusion, P/S was similar for AI and ET, although pregnancy loss between d 32 and 62 was greater for ET than for AI.


Asunto(s)
Lactancia , Progesterona , Femenino , Masculino , Embarazo , Bovinos , Animales , Estaciones del Año , Fertilidad , Transferencia de Embrión/veterinaria , Inseminación Artificial/veterinaria
3.
Acta Oncol ; 62(6): 627-634, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37335043

RESUMEN

PURPOSE: Because proton head and neck (HN) treatments are sensitive to anatomical changes, plan adaptation (re-plan) during the treatment course is needed for a significant portion of patients. We aim to predict re-plan at plan review stage for HN proton therapy with a neural network (NN) model trained with patients' dosimetric and clinical features. The model can serve as a valuable tool for planners to assess the probability of needing to revise the current plan. METHODS AND MATERIALS: Mean beam dose heterogeneity index (BHI), defined as the ratio of the maximum beam dose to the prescription dose, plan robustness features (clinical target volume (CTV), V100 changes, and V100 > 95% passing rates in 21 robust evaluation scenarios), as well as clinical features (e.g., age, tumor site, and surgery/chemotherapy status) were gathered from 171 patients treated at our proton center in 2020, with a median age of 64 and stages from I-IVc across 13 HN sites. Statistical analyses of dosimetric parameters and clinical features were conducted between re-plan and no-replan groups. A NN was trained and tested using these features. Receiver operating characteristic (ROC) analysis was conducted to evaluate the performance of the prediction model. A sensitivity analysis was done to determine feature importance. RESULTS: Mean BHI in the re-plan group was significantly higher than the no-replan group (p < .01). Tumor site (p < .01), chemotherapy status (p < .01), and surgery status (p < .01) were significantly correlated to re-plan. The model had sensitivities/specificities of 75.0%/77.4%, respectively, and an area under the ROC curve of .855. CONCLUSION: There are several dosimetric and clinical features that correlate to re-plans, and NNs trained with these features can be used to predict HN re-plans, which can be used to reduce re-plan rate by improving plan quality.


Asunto(s)
Neoplasias de Cabeza y Cuello , Terapia de Protones , Radioterapia de Intensidad Modulada , Humanos , Dosificación Radioterapéutica , Terapia de Protones/métodos , Protones , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/radioterapia , Órganos en Riesgo
4.
J Exp Biol ; 225(13)2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35662341

RESUMEN

Plasma serotonin (5-hydroxytryptamine, 5-HT) homeostasis is maintained through the combined processes of uptake (via the 5-HT transporter SERT, and others), degradation (via monoamine oxidase, MAO) and excretion. Previous studies have shown that inhibiting SERT, which would inhibit 5-HT uptake and degradation, attenuates parts of the cardiovascular hypoxia reflex in gulf toadfish (Opsanus beta), suggesting that these 5-HT clearance processes may be important during hypoxia exposure. Therefore, the goal of this experiment was to determine the effects of mild hypoxia on 5-HT uptake and degradation in the peripheral tissues of toadfish. We hypothesized that 5-HT uptake and degradation would be upregulated during hypoxia, resulting in lower plasma 5-HT, with uptake occurring in the gill, heart, liver and kidney. Fish were exposed to normoxia (97.6% O2 saturation, 155.6 Torr) or 2 min, 40 min or 24 h mild hypoxia (50% O2 saturation, ∼80 Torr), then injected with radiolabeled [3H]5-HT before blood, urine, bile and tissues were sampled. Plasma 5-HT levels were reduced by 40% after 40 min of hypoxia exposure and persisted through 24 h. 5-HT uptake by the gill was upregulated following 2 min of hypoxia exposure, and degradation in the gill was upregulated at 40 min and 24 h. Interestingly, there was no change in 5-HT uptake by the heart and degradation in the heart decreased by 58% within 2 min of hypoxia exposure and by 85% at 24 h. These results suggest that 5-HT clearance is upregulated during hypoxia and is likely driven, in part, by mechanisms within the gill and not the heart.


Asunto(s)
Batrachoidiformes , Animales , Batrachoidiformes/metabolismo , Branquias/metabolismo , Hipoxia/metabolismo , Serotonina/farmacología , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología
5.
Nature ; 535(7610): 122-6, 2016 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-27383945

RESUMEN

Chemical reactions at ultracold temperatures are expected to be dominated by quantum mechanical effects. Although progress towards ultracold chemistry has been made through atomic photoassociation, Feshbach resonances and bimolecular collisions, these approaches have been limited by imperfect quantum state selectivity. In particular, attaining complete control of the ground or excited continuum quantum states has remained a challenge. Here we achieve this control using photodissociation, an approach that encodes a wealth of information in the angular distribution of outgoing fragments. By photodissociating ultracold (88)Sr2 molecules with full control of the low-energy continuum, we access the quantum regime of ultracold chemistry, observing resonant and nonresonant barrier tunnelling, matter-wave interference of reaction products and forbidden reaction pathways. Our results illustrate the failure of the traditional quasiclassical model of photodissociation and instead are accurately described by a quantum mechanical model. The experimental ability to produce well-defined quantum continuum states at low energies will enable high-precision studies of long-range molecular potentials for which accurate quantum chemistry models are unavailable, and may serve as a source of entangled states and coherent matter waves for a wide range of experiments in quantum optics.

6.
Fish Physiol Biochem ; 48(3): 617-630, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35583623

RESUMEN

In the Gulf toadfish (Opsanus beta), the serotonin (5-HT) transporter (SERT) is highly expressed in the heart, and the heart and gill both demonstrate the capacity for SERT-mediated uptake of 5-HT from the circulation. Because 5-HT is a potent vasoconstrictor in fish, we hypothesized that hypoxia exposure may increase 5-HT uptake by these tissues-and increase excretion of 5-HT-to prevent branchial vasoconstriction that would hamper gas exchange. Spot sampling of blood, bile, and urine revealed that fish exposed to chronic hypoxia (1.83 ± 0.12 mg·L-1 O2 for 24-26 h) had 41% lower plasma 5-HT in the ventral aorta (immediately following the heart) than in the hepatic vein (immediately before the heart), suggesting enhanced cardiac 5-HT uptake during hypoxia. 5-HT concentrations in the bile were greater than those in the urine, but there were no effects of acute (1.31 ± 0.06 mg·L-1 O2 for 25 min) or chronic hypoxia on 5-HT levels in these fluids. In 5-HT radiotracer experiments, the presence of tracer in the bile decreased upon hypoxia exposure, but, surprisingly, neither acute nor chronic hypoxia-induced changes in [3H]5-HT uptake in the heart, gill, or other tissues. Given the likely impact of the hypoxia exposure on metabolic rate, future studies should examine the effects of a milder hypoxia exposure on 5-HT uptake into these tissues and the role of 5-HT degradation.


Asunto(s)
Batrachoidiformes , Serotonina , Animales , Hipoxia , Transporte Iónico , Serotonina/metabolismo , Inhibidores Selectivos de la Recaptación de Serotonina/metabolismo , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología
7.
Nature ; 519(7542): 203-6, 2015 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-25739501

RESUMEN

The Universe's largest galaxies reside at the centres of galaxy clusters and are embedded in hot gas that, if left undisturbed, would cool quickly and create many more new stars than are actually observed. Cooling can be regulated by feedback from accretion of cooling gas onto the central black hole, but requires an accretion rate finely tuned to the thermodynamic state of the hot gas. Theoretical models in which cold clouds precipitate out of the hot gas via thermal instability and accrete onto the black hole exhibit the necessary tuning. Recent observational evidence shows that the abundance of cold gas in the centres of clusters increases rapidly near the predicted threshold for instability. Here we report observations showing that this precipitation threshold extends over a large range in cluster radius, cluster mass and cosmic time. We incorporate the precipitation threshold into a framework of theoretical models for the thermodynamic state of hot gas in galaxy clusters. According to that framework, precipitation regulates star formation in some giant galaxies, while thermal conduction prevents star formation in others if it can compensate for radiative cooling and shut off precipitation.

8.
Artículo en Inglés | MEDLINE | ID: mdl-34023534

RESUMEN

The neurotransmitter serotonin (5-hyroxytryptamine, 5-HT) is involved in a variety of peripheral processes. Arguably most notable is its role as a circulating vasoconstrictor in the plasma of vertebrates. Plasma 5-HT is maintained at constant levels under normal conditions through the processes of cellular uptake, degradation, and excretion, known collectively as clearance. However, the degree to which each individual component of clearance contributes to this whole animal response remains poorly understood. The goal of this experiment was to determine the extent to which transporter-mediated uptake and intracellular degradation contribute to 5-HT clearance in the model teleost Gulf toadfish (Opsanus beta). Fish that were treated with the 5-HT transport inhibitors fluoxetine, buproprion, and decynium-22 had 1.47-fold higher plasma 5-HT concentrations and a 40% decrease in clearance rate compared to control fish. In contrast, fish treated with the MAO inhibitor clorgyline had a 1.54-fold increase in plasma 5-HT with no change in clearance rate. The results show that transporter-mediated 5-HT uptake plays an important role in controlling circulating 5-HT and whole body 5-HT homeostasis.


Asunto(s)
Batrachoidiformes/fisiología , Regulación de la Expresión Génica , Serotonina/sangre , Serotonina/farmacocinética , Animales , Transporte Biológico , Bupropión/administración & dosificación , Clorgilina/administración & dosificación , Fluoxetina/administración & dosificación , Homeostasis , Transporte Iónico , Quinolinas/administración & dosificación , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Temperatura
9.
J Dairy Sci ; 104(6): 7262-7271, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33714587

RESUMEN

Despite passing routine laboratory tests of semen quality, bulls used in artificial insemination (AI) exhibit a significant range in field fertility. The objective of this study was to determine whether subfertility in AI bulls is due to issues of sperm transport to the site of fertilization, fertilization failure, or failure of early embryo or conceptus development. In experiment 1, Holstein-Friesian bulls (3 high fertility, HF, and 3 low fertility, LF) were selected from the national population of AI bulls based on adjusted fertility scores from a minimum of 500 inseminations (HF: +4.37% and LF: -12.7%; mean = 0%). Superovulated beef heifers were blocked based on estimated number of follicles at the time of AI and inseminated with semen from HF or LF bulls (n = 3-4 heifers per bull; total 19 heifers). Following slaughter 7 d later, the number of corpora lutea was counted and the uteri were flushed. Recovered structures (oocytes/embryos) were classified according to developmental stage and stained with 4',6-diamidino-2-phenylindole to assess number of cells and accessory sperm. Overall recovery rate (total structures recovered/total corpora lutea) was 52.6% and was not different between groups. Mean (± standard error of the mean) number of embryos recovered per recipient was 8.7 ± 5.2 and 9.4 ± 5.5 for HF and LF, respectively. Overall fertilization rate of recovered structures was not different between groups. However, more embryos were at advanced stages of development (all blastocyst stages combined), reflected in a greater mean embryo cell number on d 7 for HF versus LF bulls. Number of accessory sperm was greater for embryos derived from HF than for LF bulls. The aim of experiment 2 was to evaluate the effect of sire fertility on survival of bovine embryos to d 15. Day 7 blastocysts were produced in vitro using semen from the same HF (n = 3) and LF (n = 3) bulls and transferred in groups of 5-10 to synchronized heifers (n = 7 heifers per bull; total 42 heifers). Conceptus recovery rate on d 15 was higher in HF (59.4%,) versus LF (45.0%). Mean length of recovered conceptuses for HF bulls was not affected by fertility status. In conclusion, while differences in field fertility among AI sires used in this study were not reflected in fertilization rate, differences in embryo quality were apparent as early as d 7. These differences likely contributed to the higher proportion of conceptuses surviving to d 15 in HF bulls.


Asunto(s)
Inseminación Artificial , Análisis de Semen , Animales , Bovinos , Femenino , Fertilidad , Fertilización , Inseminación Artificial/veterinaria , Masculino , Semen , Análisis de Semen/veterinaria , Espermatozoides
10.
Clin Genet ; 98(4): 331-340, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32666529

RESUMEN

Childhood dilated cardiomyopathy (DCM) is a leading cause of heart failure requiring cardiac transplantation and approximately 5% of cases result in sudden death. Knowledge of the underlying genetic cause can aid prognostication and clinical management and enables accurate recurrence risk counselling for the family. Here we used genomic sequencing to identify the causative genetic variant(s) in families with children affected by severe DCM. In an international collaborative effort facilitated by GeneMatcher, biallelic variants in PPP1R13L were identified in seven children with severe DCM from five unrelated families following exome or genome sequencing and inheritance-based variant filtering. PPP1R13L encodes inhibitor of apoptosis-stimulating protein of p53 protein (iASPP). In addition to roles in apoptosis, iASPP acts as a regulator of desmosomes and has been implicated in inflammatory pathways. DCM presented early (mean: 2 years 10 months; range: 3 months-9 years) and was progressive, resulting in death (n = 3) or transplant (n = 3), with one child currently awaiting transplant. Genomic sequencing technologies are valuable for the identification of novel and emerging candidate genes. Biallelic variants in PPP1R13L were previously reported in a single consanguineous family with paediatric DCM. The identification here of a further five families now provides sufficient evidence to support a robust gene-disease association between PPP1R13L and severe paediatric DCM. The PPP1R13L gene should be included in panel-based genetic testing for paediatric DCM.


Asunto(s)
Cardiomiopatía Dilatada/genética , Predisposición Genética a la Enfermedad , Péptidos y Proteínas de Señalización Intracelular/genética , Pediatría , Proteínas Represoras/genética , Alelos , Cardiomiopatía Dilatada/patología , Cardiomiopatía Dilatada/terapia , Niño , Preescolar , Exoma/genética , Femenino , Pruebas Genéticas , Humanos , Lactante , Masculino , Linaje
11.
J Exp Biol ; 222(Pt 18)2019 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-31466998

RESUMEN

Freshwater- and seawater-acclimated Fundulus heteroclitus were exposed to acute hypoxia (10% air saturation, 3 h), followed by normoxic recovery (3 h). In both salinities, ventilation increased and heart rate fell in the classic manner, while MO2 initially declined by ∼50%, with partial restoration by 3 h of hypoxia, and no O2 debt repayment during recovery. Gill paracellular permeability (measured with [14C] PEG-4000) was 1.4-fold higher in seawater, and declined by 50% during hypoxia with post-exposure overshoot to 188%. A similar pattern with smaller changes occurred in freshwater. Drinking rate (also measured with [14C] PEG-4000) was 8-fold higher in seawater fish, but declined by ∼90% during hypoxia in both groups, with post-exposure overshoots to ∼270%. Gill diffusive water flux (measured with 3H2O) was 1.9-fold higher in freshwater fish, and exhibited a ∼35% decrease during hypoxia, which persisted throughout recovery, but was unchanged during hypoxia in seawater fish. Nevertheless, freshwater killifish gained mass while seawater fish lost mass during hypoxia, and these changes were not corrected during normoxic recovery. We conclude that this hypoxia-tolerant teleost beneficially reduces gill water permeability in a salinity-dependent fashion during hypoxia, despite attempting to simultaneously improve MO2 , but nevertheless incurs a net water balance penalty in both freshwater and seawater.


Asunto(s)
Anaerobiosis , Fundulidae/fisiología , Branquias/fisiología , Osmorregulación/fisiología , Aclimatación , Animales , Femenino , Agua Dulce , Masculino , Oxígeno/metabolismo , Salinidad , Agua de Mar , Agua/fisiología
12.
Rheumatol Int ; 39(2): 187-201, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30649569

RESUMEN

Adherence is a primary determinant of the effectiveness of any intervention. Exercise is considered essential in the management of spondyloarthritis (SpA); however, the overall adherence to exercise programmes and factors affecting adherence are unknown. The aim of this systematic review was to examine measures of, and factors influencing adherence to, prescribed exercise programmes in people with SpA. A search was performed in August 2018 using five data bases; the Cochrane library, CINAHL, EMBASE, MEDLINE, and Web of Science Collections. Inclusion criteria were: studies with adults (> 18 years) with SpA, with a prescribed exercise intervention or educational programme with the aim of increasing exercise participation. Article quality was independently assessed by two assessors. Extracted descriptive data included: populations, interventions, measures of adherence and factors affecting adherence. Percentage adherence rates to prescribed exercises were calculated if not reported. Nine studies were included with a total of 658 participants, 95% of participants had a diagnosis of ankylosing spondylitis. Interventions and measurement of adherence varied, making comparisons difficult. Rates of adherence ranged from 51.4 to 95%. Single studies identified; adherence improved following educational programmes, and higher disease severity and longer diagnostic delays were associated with higher adherence. Conflicting evidence was found as to whether supervision of exercise improved adherence. Three consecutive studies demonstrated adherence reduced over time. Adherence to prescribed exercise in SpA was poorly reported and predominately for people with AS. The levels of adherence and factors affecting prescribed exercise in SpA remain unclear. Future research should measure adherence across a longer time period and investigate possible factors which may influence adherence.


Asunto(s)
Terapia por Ejercicio , Cooperación del Paciente , Espondiloartritis/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Garantía de la Calidad de Atención de Salud , Proyectos de Investigación
13.
Artículo en Inglés | MEDLINE | ID: mdl-31499168

RESUMEN

Gulf toadfish (Opsanus beta) can excrete the majority of their nitrogenous waste as urea in distinct pulses across their gill. Urea pulses are controlled by cortisol and serotonin (5-HT) and are believed to contain chemical signals that may communicate reproductive and/or social status. The objectives of this study were to determine if reproductive hormones are involved in controlling pulsatile urea excretion, and if toadfish respond to prostaglandins as a chemical signal. Specifically, 11-ketotestosterone (11-KT), estradiol (E2), and the teleost pheromone prostaglandin E2 (PGE2) were investigated. Castration during breeding season did not affect pulsatile urea excretion but serial injections of 11-KT outside of breeding season did result in a 48% reduction in urea pulse size in fish of both sexes. Injections of E2 and PGE2, on the other hand, did not alter urea excretion patterns. Toadfish also did not pulse urea in response to waterborne exposure of PGE2 suggesting that this compound does not serve as a toadfish pheromone alone. Toadfish have significantly higher plasma 5-HT during breeding season compared to the months following breeding season. Future research should focus on the composition of the chemical signal in toadfish and the potential importance of seasonal changes in plasma 5-HT in toadfish pulsatile urea excretion and teleost reproduction in general.


Asunto(s)
Batrachoidiformes/metabolismo , Hormonas/metabolismo , Reproducción , Urea/metabolismo , Amoníaco/sangre , Amoníaco/metabolismo , Animales , Batrachoidiformes/sangre , Dinoprostona/metabolismo , Estradiol/metabolismo , Femenino , Gónadas/metabolismo , Masculino , Estaciones del Año , Serotonina/sangre , Testosterona/análogos & derivados , Testosterona/metabolismo , Urea/sangre
14.
Am J Physiol Regul Integr Comp Physiol ; 315(6): R1154-R1166, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30303705

RESUMEN

In mammals, circulating serotonin [5-hydroxytryptamine (5-HT)] is sequestered by platelets via the 5-HT transporter (SERT) to prevent unintended signaling by this potent signaling molecule. Teleost fish appear to lack a similar circulating storage pool, although the diverse effects of 5-HT in teleosts likely necessitate an alternative method of tight regulation, such as uptake by peripheral tissues. Here, a 5-HT radiotracer was used to explore the 5-HT uptake capacity of peripheral tissues in the Gulf toadfish, Opsanus beta, and to elucidate the primary excretion routes of 5-HT and its metabolites. Pharmacological inhibition of SERT and other transporters enabled assessment of the SERT dependence of peripheral 5-HT uptake and excretion. The results indicated a rapid and substantial uptake of 5-HT by the heart atrium, heart ventricle, and gill that was at least partly SERT dependent. The results also supported the presence of a partial blood-brain barrier that prevented rapid changes in brain 5-HT content despite fluctuating plasma 5-HT concentrations. The renal pathway appeared to be the dominant excretory route for 5-HT and its metabolites over shorter time frames (up to ~30 min), but hepatic excretion was substantial over several hours. SERT inhibition ultimately reduced the excretion of 5-HT and its metabolites by urinary, biliary, and/or intestinal pathways. In addition, branchial excretion of 5-HT and its metabolites could not be ruled out. In summary, this study reveals that the toadfish heart and gill play active roles in regulating circulating 5-HT and yields important insights into the control of peripheral 5-HT in this teleost fish.


Asunto(s)
Transporte Biológico/fisiología , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Serotonina/metabolismo , Animales , Batrachoidiformes , Branquias/metabolismo , Transporte Iónico/efectos de los fármacos , Urea/metabolismo
15.
Phys Rev Lett ; 121(14): 143401, 2018 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-30339457

RESUMEN

Processes that break molecular bonds are typically observed with molecules occupying a mixture of quantum states and successfully described with quasiclassical models, while a few studies have explored the distinctly quantum mechanical low-energy regime. Here, we use photodissociation of diatomic strontium molecules to demonstrate the crossover from the ultracold, quantum regime where photofragment angular distributions strongly depend on the kinetic energy to the quasiclassical regime. Using time-of-flight imaging for photodissociation channels with millikelvin reaction barriers, we explore photofragment energies in the 0.1-300 mK range experimentally and up to 3 K theoretically, and discuss the energy scale at which the crossover occurs. We find that the effects of quantum statistics can persist to high photodissociation energies.

16.
Phys Rev Lett ; 120(3): 033201, 2018 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-29400515

RESUMEN

Photodissociation of a molecule produces a spatial distribution of photofragments determined by the molecular structure and the characteristics of the dissociating light. Performing this basic reaction at ultracold temperatures allows its quantum mechanical features to dominate. In this regime, weak applied fields can be used to control the reaction. Here, we photodissociate ultracold diatomic strontium in magnetic fields below 10 G and observe striking changes in photofragment angular distributions. The observations are in excellent agreement with a multichannel quantum chemistry model that includes nonadiabatic effects and predicts strong mixing of partial waves in the photofragment energy continuum. The experiment is enabled by precise quantum-state control of the molecules.

17.
Mol Psychiatry ; 22(7): 990-1001, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-27457810

RESUMEN

Induction of neuroprotective heat-shock proteins via pharmacological Hsp90 inhibitors is currently being investigated as a potential treatment for neurodegenerative diseases. Two major hurdles for therapeutic use of Hsp90 inhibitors are systemic toxicity and limited central nervous system permeability. We demonstrate here that chronic treatment with a proprietary Hsp90 inhibitor compound (OS47720) not only elicits a heat-shock-like response but also offers synaptic protection in symptomatic Tg2576 mice, a model of Alzheimer's disease, without noticeable systemic toxicity. Despite a short half-life of OS47720 in mouse brain, a single intraperitoneal injection induces rapid and long-lasting (>3 days) nuclear activation of the heat-shock factor, HSF1. Mechanistic study indicates that the remedial effects of OS47720 depend upon HSF1 activation and the subsequent HSF1-mediated transcriptional events on synaptic genes. Taken together, this work reveals a novel role of HSF1 in synaptic function and memory, which likely occurs through modulation of the synaptic transcriptome.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Enfermedad de Alzheimer/metabolismo , Animales , Proteínas de Unión al ADN/genética , Modelos Animales de Enfermedad , Proteínas HSP90 de Choque Térmico/metabolismo , Factores de Transcripción del Choque Térmico , Humanos , Memoria/fisiología , Trastornos de la Memoria/metabolismo , Trastornos de la Memoria/terapia , Ratones , Ratones Transgénicos , Factores de Transcripción/genética
18.
J Exp Biol ; 221(Pt 7)2018 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-29487159

RESUMEN

The serotonin transporter (SERT) functions in the uptake of the neurotransmitter serotonin (5-HT) from the extracellular milieu and is the molecular target of the selective serotonin re-uptake inhibitors (SSRIs), a common group of anti-depressants. The current study comprehensively assesses the sequence, tissue distribution, transport kinetics and physiological function of a teleost SERT. The 2022 bp toadfish SERT sequence encodes a protein of 673 amino acids, which shows 83% similarity to zebrafish SERT and groups with SERT of other teleosts in phylogenetic analysis. SERT mRNA is ubiquitous in tissues and is expressed at high levels in the heart and, within the brain, in the cerebellum. SERT cRNA expressed in Xenopus laevis oocytes demonstrates a Km value of 2.08±0.45 µmol l-1, similar to previously reported Km values for zebrafish and human SERT. Acute systemic blockade of SERT by intraperitoneal administration of the SSRI fluoxetine (FLX) produces a dose-dependent increase in plasma 5-HT, indicating effective inhibition of 5-HT uptake from the circulation. As teleosts lack platelets, which are important 5-HT sequestration sites in mammals, the FLX-induced increase in plasma 5-HT suggests that toadfish tissues may normally be responsible for maintaining low 5-HT concentrations in the bloodstream.


Asunto(s)
Batrachoidiformes/genética , Proteínas de Peces/genética , Fluoxetina/farmacología , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Serotonina/farmacología , Secuencia de Aminoácidos , Animales , Batrachoidiformes/metabolismo , Proteínas de Peces/química , Proteínas de Peces/metabolismo , Perfilación de la Expresión Génica , Filogenia , Alineación de Secuencia/veterinaria , Proteínas de Transporte de Serotonina en la Membrana Plasmática/química , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo
19.
Nature ; 488(7411): 349-52, 2012 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-22895340

RESUMEN

In the cores of some clusters of galaxies the hot intracluster plasma is dense enough that it should cool radiatively in the cluster's lifetime, leading to continuous 'cooling flows' of gas sinking towards the cluster centre, yet no such cooling flow has been observed. The low observed star-formation rates and cool gas masses for these 'cool-core' clusters suggest that much of the cooling must be offset by feedback to prevent the formation of a runaway cooling flow. Here we report X-ray, optical and infrared observations of the galaxy cluster SPT-CLJ2344-4243 (ref. 11) at redshift z = 0.596. These observations reveal an exceptionally luminous (8.2 × 10(45) erg s(-1)) galaxy cluster that hosts an extremely strong cooling flow (around 3,820 solar masses a year). Further, the central galaxy in this cluster appears to be experiencing a massive starburst (formation of around 740 solar masses a year), which suggests that the feedback source responsible for preventing runaway cooling in nearby cool-core clusters may not yet be fully established in SPT-CLJ2344-4243. This large star-formation rate implies that a significant fraction of the stars in the central galaxy of this cluster may form through accretion of the intracluster medium, rather than (as is currently thought) assembling entirely via mergers.

20.
Clin Genet ; 92(2): 221-223, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28111752

RESUMEN

Graphical abstract key: ADHD, attention deficit hyperactivity disorder; ASD, atrial septal defect; DD, developmental delay; EEG, electroencephalogram; Ht, height; ID, intellectual disability; OCD, obsessive-compulsive disorder; OFC, open fontanelle; PDA, patent ductus arteriosis; PFO, patent foramen ovale; VSD, ventricular septal defect; Wt, weight.


Asunto(s)
Predisposición Genética a la Enfermedad , Discapacidad Intelectual/genética , Convulsiones/genética , Proteínas de Transporte Vesicular/genética , Niño , Preescolar , Femenino , Estudios de Asociación Genética , Humanos , Lactante , Discapacidad Intelectual/fisiopatología , Masculino , Mutación Missense/genética , Convulsiones/fisiopatología , Secuenciación del Exoma
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