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1.
J Dairy Sci ; 106(4): 2651-2666, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36653292

RESUMEN

Chronic postpartum uterine infection detrimentally affects subsequent fertility. Nonsteroidal anti-inflammatory drugs (NSAID) are used to alleviate pain and treat inflammatory conditions in transition dairy cows with varying success. To screen the efficacy of NSAID in the absence of animal experiments, we have established an in vitro model to study uterine inflammation. Inflammation was induced in cultured bovine endometrial epithelial cells by challenging cells with an inflammation cocktail: lipopolysaccharide and proinflammatory cytokines, interleukin-1ß (IL1ß) and tumor necrosis factor α (TNFα). Release of the inflammation markers, serum amyloid A (SAA) and α-1-acid glycoprotein (αAGP), was measured by ELISA. Concentration of these markers was used to indicate the effectiveness in dampening inflammation of 5 NSAID: meloxicam, flunixin meglumine, aspirin, ketoprofen, and tolfenamic acid. Three NSAID, meloxicam, flunixin meglumine, and tolfenamic acid, were successful at dampening the release of SAA and αAGP into cell-culture supernatant, and the corresponding treated cells were selected for down-stream mRNA expression analysis. Expression of 192 genes involved in regulation of inflammatory pathways were investigated using Nanostring. Of the genes investigated, 81 were above the mRNA expression-analysis threshold criteria and were included in expression analysis. All SAA genes investigated (SAA2, SAA3, M-SAA3.2) were upregulated in response to the inflammation cocktail, relative to mRNA expression in control cells; however, AGP mRNA expression was below the expression analysis threshold and was, therefore, excluded from analysis. Treatment with NSAID downregulated genes involved in regulating chemokine signaling (e.g., CXCL2, CXCR4, CXCL5, and CXCL16) and genes that regulate the eicosanoid pathway (e.g., LTA4H, PTGS2, PLA2G4A, and PTGDS). Of the 5 NSAID investigated, meloxicam, flunixin meglumine, and tolfenamic acid are recommended for further investigation into treatment of postpartum uterine inflammation. The results from this study confirm the immunomodulatory properties of the endometrial epithelium in response to inflammatory stimuli and suggest that NSAID may be beneficial in alleviating uterine inflammation.


Asunto(s)
Enfermedades de los Bovinos , Endometritis , Femenino , Bovinos , Animales , Meloxicam , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/uso terapéutico , Inflamación/veterinaria , Endometritis/tratamiento farmacológico , Endometritis/veterinaria , ARN Mensajero/metabolismo , Células Epiteliales/metabolismo , Enfermedades de los Bovinos/tratamiento farmacológico
2.
Am J Physiol Renal Physiol ; 318(2): F422-F442, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31841389

RESUMEN

The thick ascending limb of the loop of Henle (TAL) is the first segment of the distal nephron, extending through the whole outer medulla and cortex, two regions with different composition of the peritubular environment. The TAL plays a critical role in the control of NaCl, water, acid, and divalent cation homeostasis, as illustrated by the consequences of the various monogenic diseases that affect the TAL. It delivers tubular fluid to the distal convoluted tubule and thereby affects the function of the downstream tubular segments. The TAL is commonly considered as a whole. However, many structural and functional differences exist between its medullary and cortical parts. The present review summarizes the available data regarding the similarities and differences between the medullary and cortical parts of the TAL. Both subsegments reabsorb NaCl and have high Na+-K+-ATPase activity and negligible water permeability; however, they express distinct isoforms of the Na+-K+-2Cl- cotransporter at the apical membrane. Ammonia and bicarbonate are mostly reabsorbed in the medullary TAL, whereas Ca2+ and Mg2+ are mostly reabsorbed in the cortical TAL. The peptidic hormone receptors controlling transport in the TAL are not homogeneously expressed along the cortical and medullary TAL. Besides this axial heterogeneity, structural and functional differences are also apparent between species, which underscores the link between properties and role of the TAL under various environments.


Asunto(s)
Corteza Renal/metabolismo , Médula Renal/metabolismo , Asa de la Nefrona/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Reabsorción Renal , Equilibrio Hidroelectrolítico , Adaptación Fisiológica , Animales , Evolución Molecular , Humanos , Corteza Renal/anatomía & histología , Médula Renal/anatomía & histología , Asa de la Nefrona/anatomía & histología , Proteínas de Transporte de Membrana/genética , Especificidad de la Especie
3.
J Gen Intern Med ; 31(1): 30-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26194642

RESUMEN

BACKGROUND: Triamterene, because of its potassium-sparing properties, is frequently used in combination with hydrochlorothiazide (HCTZ) to treat patients with hypertension. By inhibiting the epithelial sodium channel (ENaC) in the cortical collecting duct, triamterene reduces potassium secretion, thus reducing the risk of hypokalemia. Whether triamterene has an independent effect on blood pressure (BP) has not been well studied. OBJECTIVE: To determine if triamterene provides an effect to further lower BP in patients treated with HCTZ. DESIGN: We conducted an observational study using electronic medical record data from the Indiana Network for Patient Care. Participants were 17,291 patients with the diagnosis of hypertension between 2004 and 2012. MAIN MEASURES: BP was the primary outcome. We compared the BP between patients who were taking HCTZ, with and without triamterene, either alone or in combination with other antihypertensive medications, by using a propensity score analysis. For each medication combination, we estimated the propensity score (i.e., probability) of a patient receiving triamterene using a logistic regression model. Patients with similar propensity scores were stratified into subclasses and BP was compared between those taking triamterene or not within each subclass; the effect of triamterene was then assessed by combining BP differences estimated from all subclasses. KEY RESULTS: The mean systolic BP in the triamterene + HCTZ group was 3.8 mmHg lower than in the HCTZ only group (p < 0.0001); systolic BP was similarly lower for patients taking triamterene with other medication combinations. Systolic BP reduction was consistently observed for different medication combinations. The range of systolic BP reduction was between 1 and 4 mm Hg, depending on the concurrently used medications. CONCLUSIONS: In the present study, triamterene was found to enhance the effect of HCTZ to lower BP. In addition to its potassium-sparing action, triamterene's ability to lower BP should also be considered.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Hidroclorotiazida/administración & dosificación , Hipertensión/tratamiento farmacológico , Triantereno/administración & dosificación , Diuréticos/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
4.
Metrologia ; 53(5)2016.
Artículo en Inglés | MEDLINE | ID: mdl-32165768

RESUMEN

Using a watt balance and a frequency comb, a mass-energy equivalence is derived. The watt balance compares mechanical power measured in terms of the meter, the second, and the kilogram to electrical power measured in terms of the volt and the ohm. A direct link between mechanical action and the Planck constant is established by the practical realization of the electrical units derived from the Josephson and the quantum Hall effects. By using frequency combs to measure velocities and acceleration of gravity, the unit of mass can be realized from a set of three defining constants: the Planck constant h, the speed of light c, and the hyperfine splitting frequency of 133Cs.

5.
Int Nurs Rev ; 62(2): 218-30, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25711778

RESUMEN

BACKGROUND: Cancer pain management is still unsatisfactory, although some effective guidelines exist. Educational interventions are reported to be useful in pain relief for oncology outpatients. AIM: The aims of this systematic review were to evaluate the effects of nurse-led educational interventions on improving cancer pain outcomes for oncology patients, and to establish an effective cancer pain protocol for clinical nursing practice in China. METHODS: A three-step search strategy was utilized. Eight databases were searched using the standards provided by the Joanna Briggs Institute that guided article selection, critical appraisal, data collection and data synthesis. RESULTS: A total of 1093 studies were identified through a literature search. Only six studies complied with the inclusion criteria and were found to be methodologically sound. In general, the included studies indicated positive results pertaining to patient's knowledge and attitudes towards analgesics and cancer pain management and decreased pain intensity. Studies reported minimal effects of intervention on anxiety, depression, satisfaction regarding cancer pain management and patient's quality of life. CONCLUSIONS: Educational interventions were reported as effective methods to improve cancer pain outcomes. Analysis of the six included studies demonstrated the overall positive effects of nurse-led educational interventions for improving cancer pain management. IMPLICATIONS FOR NURSING AND HEALTH POLICY: The results suggest that an effective cancer pain protocol for improving cancer pain management can be established in China.


Asunto(s)
Neoplasias/enfermería , Enfermería Oncológica , Dolor/enfermería , Educación del Paciente como Asunto , Humanos , Relaciones Enfermero-Paciente
6.
Br J Cancer ; 111(6): 1241-8, 2014 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-25117820

RESUMEN

BACKGROUND: Bevacizumab has broad anti-tumour activity, but substantial risk of hypertension. No reliable markers are available for predicting bevacizumab-induced hypertension. METHODS: A genome-wide association study (GWAS) was performed in the phase III bevacizumab-based adjuvant breast cancer trial, ECOG-5103, to evaluate for an association between genotypes and hypertension. GWAS was conducted in those who had experienced systolic blood pressure (SBP) >160 mm Hg during therapy using binary analysis and a cumulative dose model for the total exposure of bevacizumab. Common toxicity criteria (CTC) grade 3-5 hypertension was also assessed. Candidate SNP validation was performed in the randomised phase III trial, ECOG-2100. RESULTS: When using the phenotype of SBP>160 mm Hg, the most significant association in SV2C (rs6453204) approached and met genome-wide significance in the binary model (P=6.0 × 10(-8); OR=3.3) and in the cumulative dose model (P=4.7 × 10(-8); HR=2.2), respectively. Similar associations with rs6453204 were seen for CTC grade 3-5 hypertension but did not meet genome-wide significance. Validation study from ECOG-2100 demonstrated a statistically significant association between this SNP and grade 3/4 hypertension using the binary model (P-value=0.037; OR=2.4). CONCLUSIONS: A genetic variant in SV2C predicted clinically relevant bevacizumab-induced hypertension in two independent, randomised phase III trials.


Asunto(s)
Inhibidores de la Angiogénesis/efectos adversos , Anticuerpos Monoclonales Humanizados/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Hipertensión/inducido químicamente , Hipertensión/genética , Glicoproteínas de Membrana/genética , Proteínas del Tejido Nervioso/genética , Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Bevacizumab , Biomarcadores , Presión Sanguínea , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Polimorfismo de Nucleótido Simple
7.
Clin Genet ; 86(5): 401-11, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25142969

RESUMEN

Recent years have seen significant advances in our understanding of the genetic basis of schizophrenia. In particular, genome-wide approaches have suggested the involvement of many common genetic variants of small effect, together with a few rare variants exerting relatively large effects. While unequivocal identification of the relevant genes has, for the most part, remained elusive, the genes revealed as potential candidates can in many cases be clustered into functionally related groups which are potentially open to therapeutic intervention. In this review, we summarise this information, focusing on the accumulating evidence that genetic dysfunction at glutamatergic synapses and post-synaptic signalling complexes contributes to the aetiology of the disease. In particular, there is converging support for involvement of post-synaptic JNK pathways in disease aetiology. An expansion of our neurobiological knowledge of the basis of schizophrenia is urgently needed, yet some promising novel pharmacological targets can already be discerned.


Asunto(s)
Predisposición Genética a la Enfermedad , Esquizofrenia/genética , Esquizofrenia/terapia , Humanos , Canales Iónicos/metabolismo , Receptores de Superficie Celular/metabolismo , Factores de Riesgo , Investigación Biomédica Traslacional
8.
Biochim Biophys Acta ; 1821(3): 381-5, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22260953

RESUMEN

HDL is a heterogeneous mixture of lipoprotein particles varying in composition, size, and function. We and others have described a small (7.0nm), minor (0.1% of total apolipoprotein AI) particle containing apolipoprotein AI, AIV and glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) in humans the function of which is not entirely known. Circulating GPI-PLD levels are regulated by multiple factors including genetics. To determine if genetic variation in GPLD1 affects circulating GPI-PLD levels, we examined the relationship between 32 SNPS upstream, within, and downstream of GPLD1 and circulating GPI-PLD levels in Caucasians (n=77) and African-Americans (n=99). The genotype distribution among races differed at 13 SNPs. Nine SNPS were associated with circulating GPI-PLD levels in Caucasians but not African-Americans. These results suggest that genetic variation of GPLD1 appears to associate with circulating GPI-PLD levels. This article is part of a Special Issue entitled Advances in High Density Lipoprotein Formation and Metabolism: A Tribute to John F. Oram (1945-2010).


Asunto(s)
Fosfolipasa D/sangre , Fosfolipasa D/genética , Polimorfismo de Nucleótido Simple , Adolescente , Adulto , Estudios de Cohortes , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Humanos , Desequilibrio de Ligamiento , Masculino , Análisis de Secuencia de ADN , Adulto Joven
9.
J Pediatr ; 163(5): 1317-22.e1, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23941668

RESUMEN

OBJECTIVE: To comparatively examine the effects of adiposity on the levels of plasma renin activity (PRA), plasma aldosterone concentration (PAC), and aldosterone-renin ratio (ARR) in young black and white children. STUDY DESIGN: We prospectively assessed 248 black and 345 white children and adolescents. A novel analytical technique was used to assess the concurrent influences of age and body mass index (BMI) on PRA, PAC, and ARR. The estimated effects were depicted by colored contour plots. RESULTS: In contrast to whites, blacks had lower PRA (2.76 vs 3.36 ng/mL/h; P < .001) and lower PAC (9.01 vs 14.59 ng/dL; P < .001). In blacks, BMI was negatively associated with PRA (P = .001), consistent with an association with a more expanded plasma volume; there was no association with PAC. In whites, BMI was positively associated with PAC (P = .005); we did not detect a BMI-PRA association. The effects of BMI on ARR were directionally similar in the two race groups but more pronounced in blacks. Mean systolic blood pressure was greater in blacks with lower PRA (P < .01), higher PAC (P = .015), and higher ARR (P = .49). CONCLUSIONS: An increase in adiposity was associated with a suppressed PRA in blacks and an increase in PAC in whites. The unique relationship between adiposity and renin-aldosterone axis in blacks suggests the possible existence of a population-specific mechanism characterized by volume expansion, which could in turn enhance the influences of adiposity on blood pressure in black children and adolescents.


Asunto(s)
Adiposidad/etnología , Presión Sanguínea , Sistema Renina-Angiotensina , Adolescente , Negro o Afroamericano/etnología , Factores de Edad , Aldosterona/sangre , Aldosterona/fisiología , Índice de Masa Corporal , Femenino , Humanos , Masculino , Estudios Prospectivos , Radioinmunoensayo/métodos , Renina/sangre , Renina/fisiología , Población Blanca/etnología
10.
Curr Hypertens Rep ; 15(2): 108-13, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23397215

RESUMEN

Hypertension is a more serious disease in blacks. The determinants of the blood pressure (BP) may be uniquely different from those in whites. The characteristic low-renin, salt-sensitive hypertension of blacks is consistent with the kidney reabsorbing additional sodium (Na), which leads to an expanded plasma volume that drives the BP. Mechanisms considered are genetically based. These include: (1) the intra-renal renin-angiotensin system (RAS), one based on molecular variations in angiotensinogen; (2) the Na, K, 2Cl cotransporter (NKCC2) and its regulators in the thick ascending limb, which are associated with a variety of phenotypes consistent with a more active cotransporter in blacks; and (3) the genes for MYH9 and APOL 1, which have been associated with kidney disease in blacks. To achieve a state of hypertension, an increase in Na uptake in proximal nephron regions may require a distal nephron that does not fully adjust due to less than adequate suppression of aldosterone production.


Asunto(s)
Población Negra/genética , Hipertensión/genética , Riñón/metabolismo , Apolipoproteína L1 , Apolipoproteínas/genética , Presión Sanguínea/genética , Humanos , Hipertensión/etnología , Lipoproteínas HDL/genética , Proteínas Motoras Moleculares/genética , Cadenas Pesadas de Miosina/genética , Sistema Renina-Angiotensina/genética , Simportadores de Cloruro de Sodio-Potasio/genética , Miembro 1 de la Familia de Transportadores de Soluto 12
11.
Cogn Res Princ Implic ; 8(1): 63, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37816913

RESUMEN

When a highly salient distractor is present in a search array, it speeds target absent visual search and increases errors during target present visual search, suggesting lowered quitting thresholds (Moher in Psychol Sci 31(1):31-42, 2020). Missing a critical target in the presence of a highly salient distractor can have dire consequences in real-world search tasks where accurate target detection is crucial, such as baggage screening. As such, the current study examined whether emphasizing either accuracy or speed would eliminate the distractor-generated quitting threshold effect (QTE). Three blocks of a target detection search task which included a highly salient distractor on half of all trials were used. In one block, participants received no instructions or feedback regarding performance. In the remaining two blocks, they received instructions and trial-by-trial feedback that either emphasized response speed or response accuracy. Overall, the distractor lowered quitting thresholds, regardless of whether response speed or response accuracy was emphasized in a block of trials. However, the effect of the distractor on target misses was smaller when accuracy was emphasized. It, therefore, appears that while the distractor QTE is not easily eradicated by explicit instructions and feedback, it can be shifted. As such, future research should examine the applicability of these and similar strategies in real-world search scenarios.


Asunto(s)
Atención , Percepción Visual , Humanos , Percepción Visual/fisiología , Atención/fisiología , Tiempo de Reacción
12.
Phys Rev Lett ; 107(12): 126802, 2011 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-22026784

RESUMEN

Experimental conductivity measurements made during highly stable tensile deformation of Au nanowires show a rich variety of behaviors, including noninteger quantum conductance plateaus, transitions, and slopes. Using tight binding conductance calculations on simulated nanowires previously deformed using density functional theory, we demonstrate that all of these phenomena arise from structural transitions between deeply metastable ordered atomic configurations that self-organize during tensile deformation.

13.
Surg Endosc ; 25(6): 1730-40, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21136099

RESUMEN

BACKGROUND: Bariatric surgery is a rapidly growing field. Advances in surgical technologies and techniques have raised concerns about patient safety. Bariatric surgeons and programs are under increased scrutiny from regulatory agencies, insurers, and public health officials to provide high quality and safe care for bariatric patients at all phases of care. METHODS: During the 2009 annual meeting of the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES), a panel of experts convened to provide updated information on patient safety and best practices in bariatric surgery. The following article is a summary of this panel presentation. RESULTS AND CONCLUSIONS: Weight loss surgery is a field that is evolving and adapting to multiple external pressures. Safety concerns along with increasing public scrutiny have led to a systematic approach to defining best practices, creating standards of care, and identifying mechanisms to ensure that patients consistently receive the best and most effective care possible. In many ways, bariatric surgery and multidisciplinary bariatric surgery programs may serve as a model for other programs and surgical specialties in the near future.


Asunto(s)
Cirugía Bariátrica/normas , Obesidad Mórbida/cirugía , Actitud Frente a la Salud , Benchmarking , Conducta de Elección , Humanos , Consentimiento Informado , Relaciones Interpersonales , Estado Nutricional , Obesidad Mórbida/epidemiología , Obesidad Mórbida/psicología , Apnea Obstructiva del Sueño/epidemiología
14.
Am J Physiol Regul Integr Comp Physiol ; 299(3): R977-80, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20573990

RESUMEN

A more concentrated urine is excreted by blacks than whites and by men than women. The purpose of this study was to explore the physiological bases for the race and sex effects during water deprivation when osmoregulation is challenged and differences are amplified. Drinking water was withheld from 17 blacks (10 men) and 19 whites (9 men) for 24 h. Vasopressin (VP) levels and osmolality in plasma (P(osmol)) and urine (U(osmol)) were measured basally and then every 4 h. U(osmol) was higher in blacks at baseline (P = 0.01) and during water deprivation (P = 0.046). Before and during water deprivation, no differences were seen in levels of VP, P(osmol), or the VP-U(osmol) relationship between blacks and whites. Although VP levels were initially higher in men (P < 0.02 for samples collected over the first 12 h), over the last 12 h of water deprivation, U(osmol) was higher (P = 0.027) and more responsive to the level of VP (in terms of slopes, P = 0.0001) in women than men. Our results suggest that, after a period of water deprivation, there develops a sensitivity of the collecting duct to VP that is greater in women. Although U(osmol) is higher in blacks, the race difference in water conservation did not appear to result from differences in the level of VP or the sensitivity of the collecting duct to VP. Upstream effects such as Na(+) uptake in the thick ascending limb, with its ensuing effects on water reabsorption, need to be considered in future studies of the relationship of race to water conservation.


Asunto(s)
Negro o Afroamericano , Concentración Osmolar , Caracteres Sexuales , Orina/química , Privación de Agua/fisiología , Población Blanca , Adolescente , Adulto , Femenino , Humanos , Masculino , Factores de Tiempo , Adulto Joven
15.
Neuroimmunomodulation ; 16(2): 122-33, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19212132

RESUMEN

Toxoplasma gondii infects approximately 30% of the world's population, but causes overt clinical symptoms in only a small proportion of people. In recent years, the ability of the parasite to manipulate the behaviour of infected mice and rats and alter personality attributes of humans has been reported. Furthermore, a number of studies have now suggested T. gondii infection as a risk factor for the development of schizophrenia and depression in humans. As T. gondii forms cysts that are located in various anatomical sites including the brain during a chronic infection, it is well placed anatomically to mediate these effects directly. The T. gondii genome is known to contain 2 aromatic amino acid hydroxylases that potentially could directly affect dopamine and/or serotonin biosynthesis. However, stimulation of the immune response has also recently been associated with mood and behavioural alterations in humans, and compounds designed to alter mood, such as fluoxetine, have been demonstrated to alter aspects of immune function. Herein, the evidence for T.-gondii-induced behavioural changes relevant to schizophrenia and depression is reviewed. Potential mechanisms responsible for these changes in behaviour including the role of tryptophan metabolism and the hypothalamic-pituitary-adrenal axis are discussed.


Asunto(s)
Trastornos Mentales/etiología , Enfermedades del Sistema Nervioso/etiología , Toxoplasmosis/psicología , Animales , Conducta , Conducta Animal , Gatos , Citocinas/fisiología , Depresión/epidemiología , Depresión/etiología , Depresión/parasitología , Dopamina/metabolismo , Femenino , Interacciones Huésped-Parásitos , Humanos , Masculino , Trastornos Mentales/epidemiología , Trastornos Mentales/parasitología , Trastornos Mentales/fisiopatología , Ratones , Enfermedades del Sistema Nervioso/epidemiología , Enfermedades del Sistema Nervioso/parasitología , Enfermedades del Sistema Nervioso/fisiopatología , Neuronas/parasitología , Sistemas Neurosecretores/fisiopatología , Proteínas Protozoarias/fisiología , Ratas , Factores de Riesgo , Esquizofrenia/epidemiología , Esquizofrenia/etiología , Esquizofrenia/parasitología , Serotonina/metabolismo , Toxoplasma/enzimología , Toxoplasma/crecimiento & desarrollo , Toxoplasma/fisiología , Toxoplasmosis/epidemiología , Toxoplasmosis/inmunología , Toxoplasmosis/fisiopatología , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/inmunología , Toxoplasmosis Animal/parasitología , Toxoplasmosis Animal/fisiopatología , Triptófano/metabolismo
17.
Br J Pharmacol ; 153 Suppl 1: S465-70, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18311160

RESUMEN

Current treatments of schizophrenia are compromised by their inability to treat all symptoms of the disease and their side-effects. Whilst existing antipsychotic drugs are effective against positive symptoms, they have negligible efficacy against the prefrontal cortex (PFC)-associated cognitive deficits and negative symptoms. New models that reproduce core pathophysiological features of schizophrenia are more likely to have improved predictive validity in identifying new treatments. We have developed a NMDA receptor antagonist model that reproduces core PFC deficits of schizophrenia and discuss this in relation to pathophysiology and treatments. Subchronic and chronic intermittent PCP (2.6 mg/kg i.p.) was administered to rats. PFC activity was assessed by 2-deoxyglucose imaging, parvalbumin and Kv3.1 mRNA expression, and the attentional set-shifting test (ASST) of executive function. Affymetrix gene array technology was employed to examine gene expression profile patterns. PCP treatment reduced glucose utilization in the PFC (hypofrontality). This was accompanied by a reduction in markers of GABAergic interneurones (parvalbumin and Kv3.1 mRNA expression) and deficits in the extradimensional shift dimension of the ASST. Consistent with their clinical profile, the hypofrontality was not reversed by clozapine or haloperidol. Transcriptional analysis revealed patterns of change consistent with current neurobiological theories of schizophrenia. This model mirrors core neurobiological deficits of schizophrenia; hypofrontality, altered markers of GABAergic interneurone activity and deficits in executive function. As such it is likely to be a valuable translational model for understanding the neurobiological mechanisms underlying hypofrontality and for identifying and validating novel drug targets that may restore PFC deficits in schizophrenia.


Asunto(s)
Antipsicóticos/uso terapéutico , Corteza Prefrontal/patología , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/patología , Animales , Antipsicóticos/farmacología , Modelos Animales de Enfermedad , Antagonistas de Aminoácidos Excitadores , Humanos , Fenciclidina , Corteza Prefrontal/efectos de los fármacos , Psicosis Inducidas por Sustancias/tratamiento farmacológico , Psicosis Inducidas por Sustancias/psicología , Ácido gamma-Aminobutírico/fisiología
18.
Hypertension ; 72(1): 247-252, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29785962

RESUMEN

Aldosterone sensitivity, defined as the magnitude of the association of plasma aldosterone concentration with blood pressure (BP), seems to be a function of plasma volume. It increases as plasma renin activity decreases, and it is more significant in blacks but less so in whites. Age is a strong determinant of BP, and an increase in aldosterone sensitivity could contribute to the increase in BP. In the present study, we tested the hypothesis that aldosterone sensitivity increases with age. We used observational data collected from normotensive blacks and whites enrolled in a prospective cohort study. They were studied as children (248 blacks/357 whites) and again as young adults (74 blacks/125 whites) over an age range of 7 to 39 years. A varying-coefficient regression analysis was used to explore the influences of aldosterone on systolic BP. After controlling for body mass index, race, and sex, both plasma renin activity and plasma aldosterone concentration were lower in blacks, and their levels declined with age (P<0.001). In blacks, plasma aldosterone concentration decreased 0.25 ng/dL per year; in whites, plasma aldosterone concentration decreased 0.18 per year. Aldosterone's effect on BP, characterized by a smooth function of age, intensified as age increased, especially in blacks (P<0.01), suggesting an increased aldosterone sensitivity with age. In comparison to blacks, age-related changes in aldosterone sensitivity in whites were not statistically significant. These findings extend the rationale for targeting aldosterone in the treatment of hypertension, especially in blacks.


Asunto(s)
Aldosterona/metabolismo , Negro o Afroamericano , Presión Sanguínea/fisiología , Hipertensión/fisiopatología , Sistema Renina-Angiotensina/fisiología , Población Blanca , Adolescente , Adulto , Biomarcadores/sangre , Biomarcadores/orina , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/etnología , Incidencia , Masculino , Pronóstico , Estudios Prospectivos , Estados Unidos/epidemiología , Adulto Joven
19.
Endocrinology ; 148(3): 1424-30, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17158202

RESUMEN

The renin gene is regulated by an enhancer located 2.6 kb upstream of the transcription start site in the mouse and 11 kb upstream in humans. Despite extensive sequence conservation, the mouse renin enhancer is transcriptionally more active than the human renin enhancer. We report that the mechanism accounting for this is a result of sequence variation in the promoter proximal half-site of a retinoic-acid response element present in the enhancer. This sequence difference also prompted us to search for naturally occurring polymorphisms in the renin enhancer among normal and hypertensive human subjects. We sequenced the kidney enhancer from 90 samples derived from the Coriell Polymorphism Discovery Resource and 95 severely hypertensive Caucasian and African-American individuals. A single relatively frequent polymorphism (7, 2, and 7%, respectively in the Coriell, African-American, and Caucasian) was identified in the enhancer, one nucleotide downstream of the promoter distal half-site of the retinoic-acid response element. This variant was transcriptionally silent in transfection assays performed in renin-expressing As4.1 cells, a model of renal juxtaglomerular cells. A singleton polymorphism in the promoter was also identified in a single African-American individual. This polymorphism was located between binding sites for CBF1 and homeobox D10 but was also transcriptionally silent either in the presence or absence of the enhancer. Our study demonstrates the presence of silent polymorphisms in the renin promoter and enhancer, thus underscoring the critical importance of performing functional analyses before initiating expensive clinical studies seeking association between polymorphisms and complex diseases such as hypertension.


Asunto(s)
Elementos de Facilitación Genéticos , Polimorfismo Genético , Renina/genética , Animales , Secuencia de Bases , Células Cultivadas , Análisis Mutacional de ADN , Genes Reporteros , Humanos , Riñón/metabolismo , Ratones , Datos de Secuencia Molecular , Renina/metabolismo , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie , Transfección
20.
J Clin Invest ; 70(3): 667-72, 1982 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6286729

RESUMEN

Potassium is known to enhance the aldosterone-stimulating action of angiotensin II. Such a synergistic interaction of potassium with angiotensin II could represent an action by angiotensin II to potentiate potassium as a stimulus. To examine for this effect of angiotensin II on potassium, plasma aldosterone levels were measured before and after an infusion of potassium chloride (15 meq i.v.) into dogs without and with prevention of angiotensin II formation by captopril, an angiotensin converting-enzyme inhibitor. In addition, responses to potassium were measured in a group of dogs receiving angiotensin II plus captopril. After potassium infusion, control dogs showed an increase of 7.7 +/- 1.9 (SEM) ng/dl (P less than 0.001) in the level of plasma aldosterone. In contrast, captopril-treated dogs showed no change in plasma aldosterone concentration in response to potassium. When angiotensin II was administered to captopril-treated dogs responsiveness to potassium administration was restored (plasma aldosterone concentration increased by 7.4 +/- 2.1 ng/dl, P less than 0.002). ACTH stimulated aldosterone secretion despite captopril treatment (P less than 0.001), however, ACTH produced a greater increase in the plasma aldosterone concentration in controls than in captopril-treated animals. It is evident from these results that stimulation of aldosterone secretion by potassium is considerably enhanced by angiotensin II. There appears to exist an important interdependence of these stimuli in the regulation of aldosterone secretion.


Asunto(s)
Aldosterona/metabolismo , Angiotensina II/fisiología , Potasio/fisiología , Hormona Adrenocorticotrópica/farmacología , Animales , Captopril/farmacología , Perros , Potasio/sangre , Renina/sangre , Sodio/sangre
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