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1.
Mol Psychiatry ; 26(9): 5371-5388, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33526823

RESUMEN

Schizophrenia (Sz) is a highly polygenic disorder, with common, rare, and structural variants each contributing only a small fraction of overall disease risk. Thus, there is a need to identify downstream points of convergence that can be targeted with therapeutics. Reduction of microtubule-associated protein 2 (MAP2) immunoreactivity (MAP2-IR) is present in individuals with Sz, despite no change in MAP2 protein levels. MAP2 is phosphorylated downstream of multiple receptors and kinases identified as Sz risk genes, altering its immunoreactivity and function. Using an unbiased phosphoproteomics approach, we quantified 18 MAP2 phosphopeptides, 9 of which were significantly altered in Sz subjects. Network analysis grouped MAP2 phosphopeptides into three modules, each with a distinct relationship to dendritic spine loss, synaptic protein levels, and clinical function in Sz subjects. We then investigated the most hyperphosphorylated site in Sz, phosphoserine1782 (pS1782). Computational modeling predicted phosphorylation of S1782 reduces binding of MAP2 to microtubules, which was confirmed experimentally. We generated a transgenic mouse containing a phosphomimetic mutation at S1782 (S1782E) and found reductions in basilar dendritic length and complexity along with reduced spine density. Because only a limited number of MAP2 interacting proteins have been previously identified, we combined co-immunoprecipitation with mass spectrometry to characterize the MAP2 interactome in mouse brain. The MAP2 interactome was enriched for proteins involved in protein translation. These associations were shown to be functional as overexpression of wild type and phosphomimetic MAP2 reduced protein synthesis in vitro. Finally, we found that Sz subjects with low MAP2-IR had reductions in the levels of synaptic proteins relative to nonpsychiatric control (NPC) subjects and to Sz subjects with normal and MAP2-IR, and this same pattern was recapitulated in S1782E mice. These findings suggest a new conceptual framework for Sz-that a large proportion of individuals have a "MAP2opathy"-in which MAP function is altered by phosphorylation, leading to impairments of neuronal structure, synaptic protein synthesis, and function.


Asunto(s)
Esquizofrenia , Animales , Ratones , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Neuronas/metabolismo , Fosforilación , Esquizofrenia/genética , Esquizofrenia/metabolismo
2.
Vox Sang ; 101(3): 247-9, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21521234

RESUMEN

During 2009/2010 loss of platelets within NHS Blood and Transplant (NHSBT) due to time expiry was 9.3%. Hospitals remain reluctant to hold stocks of platelets due to the poor shelf life at issue. The purpose of this study was to identify areas for time compression in the apheresis platelet supply chain to extend the shelf life available for hospitals and reduce wastage in NHSBT. This was done within the context of NHSBT reconfiguring their supply chain and moving towards a consolidated and centralised approach. Time based process mapping was applied to identify value and non-value adding time in two manufacturing models. A large amount of the non-value adding time in the apheresis platelet supply chain is due to transportation and waiting for the next process in the manufacturing process to take place. Time based process mapping provides an effective 'lens' for supply chain professionals to identify opportunities for improvement in the platelet supply chain.


Asunto(s)
Plaquetas , Equipos y Suministros de Hospitales/provisión & distribución , Hospitales , Plaquetoferesis , Transportes , Inglaterra , Equipos y Suministros de Hospitales/normas , Femenino , Humanos , Masculino , Factores de Tiempo
3.
Sci Rep ; 9(1): 20005, 2019 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-31882800

RESUMEN

Multiple approaches utilizing viral and DNA vectors have shown promise in the development of an effective vaccine against HIV. In this study, an alternative replication-defective flavivirus vector, RepliVax (RV), was evaluated for the delivery of HIV-1 immunogens. Recombinant RV-HIV viruses were engineered to stably express clade C virus Gag and Env (gp120TM) proteins and propagated in Vero helper cells. RV-based vectors enabled efficient expression and correct maturation of Gag and gp120TM proteins, were apathogenic in a sensitive suckling mouse neurovirulence test, and were similar in immunogenicity to recombinant poxvirus NYVAC-HIV vectors in homologous or heterologous prime-boost combinations in mice. In a pilot NHP study, immunogenicity of RV-HIV viruses used as a prime or boost for DNA or NYVAC candidates was compared to a DNA prime/NYVAC boost benchmark scheme when administered together with adjuvanted gp120 protein. Similar neutralizing antibody titers, binding IgG titers measured against a broad panel of Env and Gag antigens, and ADCC responses were observed in the groups throughout the course of the study, and T cell responses were elicited. The entire data demonstrate that RV vectors have the potential as novel HIV-1 vaccine components for use in combination with other promising candidates to develop new effective vaccination strategies.


Asunto(s)
Vacunas contra el SIDA/inmunología , Virus Defectuosos/genética , Flavivirus/genética , Vectores Genéticos , VIH-1/inmunología , Vacunas Sintéticas/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Chlorocebus aethiops , Reacciones Cruzadas , Femenino , Infecciones por VIH/virología , VIH-1/patogenicidad , Macaca mulatta , Ratones , Ratones Endogámicos BALB C , Células Vero , Virulencia
4.
Mucosal Immunol ; 9(3): 821-833, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26813340

RESUMEN

The impact of topical antiretrovirals for pre-exposure prophylaxis on humoral responses following HIV infection is unknown. Using a binding antibody multiplex assay, we investigated HIV-specific IgG and IgA responses to envelope glycoproteins, p24 Gag and p66, in the genital tract (GT) and plasma following HIV acquisition in women assigned to tenofovir gel (n=24) and placebo gel (n=24) in the CAPRISA 004 microbicide trial to assess if this topical antiretroviral had an impact on mucosal and systemic antibody responses. Linear mixed effect modeling and partial least squares discriminant analysis was used to identify multivariate antibody signatures associated with tenofovir use. There were significantly higher response rates to gp120 Env (P=0.03), p24 (P=0.002), and p66 (P=0.009) in plasma and GT in women assigned to tenofovir than placebo gel at multiple time points post infection. Notably, p66 IgA titers in the GT and plasma were significantly higher in the tenofovir compared with the placebo arm (P<0.05). Plasma titers for 9 of the 10 HIV-IgG specificities predicted GT levels. Taken together, these data suggest that humoral immune responses are increased in blood and GT of individuals who acquire HIV infection in the presence of tenofovir gel.


Asunto(s)
Antirretrovirales/uso terapéutico , Genitales Femeninos/efectos de los fármacos , Anticuerpos Anti-VIH/metabolismo , Infecciones por VIH/tratamiento farmacológico , VIH-1/inmunología , Inmunoglobulina A/metabolismo , Tenofovir/uso terapéutico , Administración Tópica , Adulto , Femenino , Estudios de Seguimiento , Genitales Femeninos/inmunología , Genitales Femeninos/metabolismo , Proteína p24 del Núcleo del VIH/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/inmunología , Transcriptasa Inversa del VIH/inmunología , Humanos , Inmunoglobulina G/metabolismo , Resultado del Tratamiento , Cremas, Espumas y Geles Vaginales , Adulto Joven
5.
Mucosal Immunol ; 8(2): 316-26, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25100291

RESUMEN

A successful HIV-1 vaccine must elicit immune responses that impede mucosal virus transmission, though functional roles of protective HIV-1 Envelope (Env)-specific mucosal antibodies remain unclear. Colostrum is a rich source of readily accessible mucosal B cells that may help define the mucosal antibody response contributing to prevention of postnatal HIV-1 transmission. To examine the HIV-1 Env-specific colostrum B-cell repertoire, single B cells were isolated from 17 chronically HIV-infected, lactating women, producing 51 blood and 39 colostrum HIV-1 Env-specific B-cell antibodies. All HIV-1 Env-specific colostrum-derived antibodies were immunoglobulin (Ig)G1 isotype and had mean heavy chain complementarity-determining region 3 (CDR3) lengths and mutation frequencies similar to those isolated from blood. However, variable heavy chain (VH) gene subfamily 1(∼)69 usage was higher among colostrum than blood HIV-1 Env-reactive antibodies (49% vs. 20%, P=0.006, Fisher's exact test). Additionally, more HIV-1 Env-specific colostrum antibodies were gp120 specific than those isolated from blood (44% vs. 16%, P=0.005, Fisher's exact test). One cross-compartment HIV-1 Env-specific clonal B-cell lineage was identified. These unique characteristics of colostrum B-cell antibodies suggest selective homing of HIV-1-specific IgG1-secreting memory B cells to the mammary gland and have implications for targeting mucosal B-cell populations by vaccination.


Asunto(s)
Linfocitos B/inmunología , Linfocitos B/metabolismo , Calostro/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/genética , Infecciones por VIH/inmunología , VIH-1/inmunología , Lactancia , Negro o Afroamericano , Formación de Anticuerpos/inmunología , Linfocitos B/citología , Recuento de Linfocito CD4 , Evolución Clonal , Calostro/citología , Regiones Determinantes de Complementariedad/genética , Epítopos de Linfocito B/inmunología , Femenino , Anticuerpos Anti-VIH/inmunología , Proteína gp41 de Envoltorio del VIH/inmunología , Infecciones por VIH/sangre , Infecciones por VIH/transmisión , Infecciones por VIH/virología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Memoria Inmunológica , Inmunofenotipificación , Transmisión Vertical de Enfermedad Infecciosa , Tasa de Mutación , Fenotipo , Hipermutación Somática de Inmunoglobulina , Carga Viral
6.
Br J Pharmacol ; 108(3): 627-30, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8385530

RESUMEN

1. The presence of an endogenous digitalis-like factor (EDLF) in the plasma of both normal and volume expanded animals is well documented. In this study we have used ouabain and bufalin as pharmacological analogues to mimic the renal effects of EDLF and to investigate whether any interaction occurs between atrial natriuretic factor (ANF) and EDLF. 2. Conscious Na replete sheep with chronically indwelling catheters in the renal artery received renal arterial infusion of ouabain (1000 micrograms h-1) or bufalin (500 micrograms h-1) for 60 min. Renal arterial infusion of bufalin increased sodium excretion (UNaV) from 120 +/- 13 to 596 +/- 161 mumol min-1 after 45 min. Bufalin infusion did not alter glomerular filtration rate (GFR), effective renal plasma flow (ERPF), or lithium clearance. Ouabain infusion increased UNaV from 124 +/- 57 to 764 +/- 123 mumol min-1 in the first hour after infusion. 3. ANF infusion increased UNaV from 159 +/- 34 to 583 +/- 134 mumol min-1. When renal arterial bufalin infusion was followed by renal arterial ANF infusion (50 micrograms h-1) UNaV was increased from 155 +/- 31 to 795 +/- 96 mumol min-1. This increase in UNaV is approximately equal to the sum of the separate effects of bufalin and ANF. 4. The natriuretic effects of ouabain at pharmacological doses in sheep are confirmed by this study. The data presented here do not support the hypothesis that EDLF sensitizes the kidney to the natriuretic effects of ANF.


Asunto(s)
Bufanólidos/farmacología , Digoxina , Natriuresis/efectos de los fármacos , Ouabaína/farmacología , Saponinas , Animales , Factor Natriurético Atrial/farmacología , Presión Sanguínea/efectos de los fármacos , Proteínas Sanguíneas/farmacología , Bufanólidos/administración & dosificación , Cardenólidos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Infusiones Intraarteriales , Ouabaína/administración & dosificación , Potasio/orina , Arteria Renal , Circulación Renal/efectos de los fármacos , Ovinos , Sodio/orina , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores
7.
J Endocrinol ; 130(2): 213-21, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1919393

RESUMEN

Indirect evidence has suggested that the kidney is a major organ of clearance for osteocalcin, a circulating marker of osteoblast function. The objectives of the present study were (1) to confirm the role of the kidney in osteocalcin clearance (2) to quantify the contribution of extrarenal sites and (3) to investigate the renal mechanism(s) of osteocalcin clearance. Plasma osteocalcin levels, osteocalcin plasma clearance rate (PCR) and plasma production rate (PPR) were determined in oophorectomized (OX) and uninephrectomized oophorectomized (UOX) sheep. The osteocalcin renal extraction efficiency (REE) and the effective renal plasma flow (ERPF) were measured, and the osteocalcin renal clearance rate (RCR) was calculated. The osteocalcin PCR was reduced significantly in UOX compared with OX sheep (2.0 +/- 0.1 (n = 9) vs 2.5 +/- 0.1 litres/h (n = 44); P less than 0.0005). In UOX sheep with plasma creatinine levels less than or equal to 130 mumol/l, the osteocalcin REE was 9 +/- 1.3% and the osteocalcin RCR was 50-91% of osteocalcin PCR (n = 4). In UOX sheep with plasma creatinine levels in the range 100-440 mumol/l, there was a linear relationship between osteocalcin PCR and ERPF; the osteocalcin RCR was related to the osteocalcin PCR (RCR = 0.9 x PCR - 0.50). Intravenous infusion of the synthetic glucocorticoid triamcinolone acetonide (TA) in UOX sheep led to marked decrements in plasma osteocalcin levels and the osteocalcin PPR, and a significant increase in the osteocalcin PCR. These changes were accompanied by a 44% increase in ERPF.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Riñón/metabolismo , Osteocalcina/metabolismo , Ovinos/metabolismo , Animales , Femenino , Radioisótopos de Yodo , Riñón/irrigación sanguínea , Riñón/efectos de los fármacos , Riñón/cirugía , Tasa de Depuración Metabólica , Osteocalcina/sangre , Osteocalcina/farmacocinética , Osteocalcina/orina , Flujo Sanguíneo Regional/efectos de los fármacos , Triamcinolona Acetonida/farmacología
8.
Life Sci ; 50(24): 1905-12, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1534598

RESUMEN

The renal and cardiovascular effects of ANF infusion have been examined in separate series of experiments; in conscious instrumented sheep following either hemorrhage (10 mL/kg body weight) or removal of 500 mL of plasma by ultrafiltration. Renal arterial infusion of hANF (99-126) at 50 micrograms/h increased sodium excretion from 99 +/- 30 to 334 +/- 102 (p less than 0.05) in normal animals, and from 77 +/- 31 to 354 +/- 118 mumol/min in hemorrhaged animals. Similarly in sheep following ultrafiltration, cardiac output and stroke volume were reduced by intravenous infusion of ANF (100 micrograms/h), although these effects were less marked than those observed in normal animals. The rapid modulation of natriuretic responses to ANF observed in volume expanded animals is not seen in this model of acute volume depletion suggesting that the mechanism through which the renal response to ANF is modulated in low sodium or volume states is not simply the reverse of that which produces rapid enhancement of response following blood volume expansion.


Asunto(s)
Factor Natriurético Atrial/farmacología , Volumen Sanguíneo/fisiología , Sistema Cardiovascular/efectos de los fármacos , Riñón/efectos de los fármacos , Animales , Fenómenos Fisiológicos Cardiovasculares , Estado de Conciencia , Hemodinámica/efectos de los fármacos , Hemodinámica/fisiología , Hemofiltración , Infusiones Intravenosas , Riñón/fisiología , Renina , Ovinos , Ultrafiltración
9.
J Photochem Photobiol B ; 4(4): 379-90, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2111384

RESUMEN

Metal naphthalocyanine complexes (MNCSs) absorb light in the near-IR spectral region (760 nm) where tissue penetration is optimal and they have been proposed as agents for photodynamic therapy (PDT). Sulphonated derivatives of tris-(2,3-naphthalocyanato) bis-chloroaluminium(III) and zinc(II) with various degrees of sulphonation were prepared. Cellular uptake, aggregation in cellular environments, cytotoxicity and photosensitizing properties were studied. Three of the four dyes studied were taken up by cells to a satisfactory degree and were not cytotoxic at the concentration used (10 micrograms ml-1). The least sulphonated sample of zinc naphthalocyanine produced some phototoxic effects (LD50 = 1.12 J cm-2). All the other samples of sulphonated naphthalocyanine were found to be aggregated inside the NHIK 3025 cells, preventing any significant PDT effect.


Asunto(s)
Naftalenosulfonatos/farmacología , Compuestos Organometálicos/farmacología , Fármacos Sensibilizantes a Radiaciones , Células Tumorales Cultivadas/efectos de los fármacos , Transporte Biológico Activo , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Colorantes , Humanos , Rayos Infrarrojos , Naftalenosulfonatos/farmacocinética , Naftalenosulfonatos/toxicidad , Compuestos Organometálicos/farmacocinética , Compuestos Organometálicos/toxicidad , Fotoquímica , Fármacos Sensibilizantes a Radiaciones/farmacocinética , Fármacos Sensibilizantes a Radiaciones/toxicidad , Solubilidad , Espectrofotometría Infrarroja , Células Tumorales Cultivadas/metabolismo , Células Tumorales Cultivadas/efectos de la radiación , Agua
10.
Am Surg ; 67(6): 597-600, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11409812

RESUMEN

The purpose of this study was to assess the impact of increased use of nonoperative management of blunt injuries to the spleen or liver on surgical residents' operative experience with solid visceral injuries. We conducted a 10-year retrospective study of blunt spleen and liver injuries at a state-designated Level I trauma center and a survey of chief residents' operative experience with splenic and hepatic injuries from blunt trauma during the same time period. From 1990 through 1999, 431 patients were admitted with splenic injuries and 634 patients were admitted with liver injuries; 350 splenic injuries (81%) were due to blunt trauma; 317 liver injuries (50%) were caused by blunt mechanisms. In 1990 100 per cent of patients with splenic injuries and 93 per cent of those with liver injuries underwent surgery for those injuries. These rates were 19 and 28 per cent respectively in 1999. The number of patients with blunt solid visceral injuries increased more than fourfold from 1990 through 1999. The number of operations for splenic and hepatic injuries performed by chief residents did not decline significantly during this time period (5.5 cases per chief resident in 1990; 4.6 cases per chief resident in 1999). The increased numbers of patients with solid visceral injuries were due to two factors: increased proportion of blunt trauma admissions especially from motor vehicle collisions and improved recognition of spleen and liver injuries by expanded use of CT scans. We conclude that nonoperative management of blunt solid visceral injuries does not necessarily lead to a diminution of operations nor jeopardize resident education. However, trauma volumes must be high enough to support adequate operative experience.


Asunto(s)
Cirugía General/educación , Internado y Residencia , Hígado/lesiones , Bazo/lesiones , Heridas no Penetrantes/terapia , Accidentes de Tránsito , Humanos , Mississippi/epidemiología , Procedimientos Quirúrgicos Operativos/estadística & datos numéricos , Heridas no Penetrantes/epidemiología
11.
Bioresour Technol ; 83(2): 115-24, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12056486

RESUMEN

Switchgrass (Panicum virgatum L.) and coastal panic grass (Panicum amarum A.S. Hitchc. & Chase) are perennial grasses indigenous to North America. Switchgrass has been shown to have good potential as a biofuel crop in both the US and Canada. In the study reported here, seven varieties of switchgrass and one panic grass were evaluated for 5 years under the temperate maritime conditions in Southern England. Both species had 0 or 60 kg N ha(-1) applied annually in spring as treatment. Yield was measured after flowering and when stems were dead in the winter. Yield increased annually for 4-5 years except for the variety Dacotah, and in the fifth year dead stem yields ranged from 8.82 to 13.97 t dm ha(-1). There was no response to N except for one variety in one year. Mineral concentration in biomass was higher at flowering than at dead stem harvest and delaying harvesting further provided more time for P, K and Cl to be leached but yield also declined.


Asunto(s)
Fuentes Generadoras de Energía , Poaceae , Agricultura , Cloro , Inglaterra , Fósforo , Potasio , Estaciones del Año , Suelo , Temperatura , Factores de Tiempo , Tiempo (Meteorología)
12.
Mucosal Immunol ; 6(4): 692-703, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23299618

RESUMEN

Prevention of HIV-1 transmission at mucosal surfaces will likely require durable pre-existing mucosal anti-HIV-1 antibodies (Abs). Defining the ontogeny, specificities and potentially protective nature of the initial mucosal virus-specific B-cell response will be critical for understanding how to induce protective Ab responses by vaccination. Genital fluids from patients within the earliest stages of acute HIV-1 infection (Fiebig I-VI) were examined for multiple anti-HIV specificities. Gp41 (but not gp120) Env immunoglobulin (Ig)A Abs were frequently elicited in both plasma and mucosal fluids within the first weeks of transmission. However, shortly after induction, these initial mucosal gp41 Env IgA Abs rapidly declined with a t(½) of ∼2.7 days. B-cell-activating factor belonging to the TNF family (BAFF) was elevated immediately preceding the appearance of gp41 Abs, likely contributing to an initial T-independent Ab response. HIV-1 transmission frequently elicits mucosal HIV-1 envelope-specific IgA responses targeted to gp41 that have a short half-life.


Asunto(s)
Proteína gp41 de Envoltorio del VIH/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Inmunoglobulina A/inmunología , Especificidad de Anticuerpos/inmunología , Factor Activador de Células B/metabolismo , Linfocitos B/inmunología , Linfocitos B/metabolismo , Femenino , Infecciones por VIH/metabolismo , Infecciones por VIH/transmisión , Humanos , Inmunidad Mucosa , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Activación de Linfocitos/inmunología , Masculino , Factores de Tiempo
14.
Bioresour Technol ; 101(15): 6185-91, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20338753

RESUMEN

The objectives of the experiment were to assess the impact of nitrogen (N) and potassium (K) fertiliser application on the cell wall composition and fast-pyrolysis conversion quality of the commercially cultivated hybrid Miscanthus x giganteus. Five different fertiliser treatments were applied to mature Miscanthus plants which were sampled at five intervals over a growing season. The different fertiliser treatments produced significant variation in concentrations of cell wall components and ash within the biomass and affected the composition and quality of the resulting fast-pyrolysis liquids. The results indicated that application of high rates of N fertiliser had a negative effect on feedstock quality for this conversion pathway: reducing the proportion of cell wall components and increasing accumulation of ash in the harvested biomass. No exclusive effect of potassium fertiliser was observed. The low-N fertiliser treatment produced high quality, low ash-high lignin biomass most suitable as a feedstock for thermo-chemical conversion.


Asunto(s)
Fertilizantes , Poaceae/efectos de los fármacos , Poaceae/fisiología , Agricultura/métodos , Calor
15.
Lab Anim ; 44(3): 163-9, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20427379

RESUMEN

The future laboratory animal technician in Europe will be provided with three different levels of education. All candidates have to start with an introductory course to reach level A0. At this level (A0) they will be able to assist in the laboratory animal facility by undertaking limited specific duties under supervision. Most A0 assistants will continue their education and training for at least one year while in full-time employment. This process will include continual assessment with the option of a final examination to become qualified at level A1. A1 represents a comprehensively educated laboratory animal technician with theoretical background knowledge and practical skills. Some of the A1 laboratory animal technicians may continue specific education for at least another year of full-time employment. They will develop knowledge and expertise as well as supervisory and basic managerial skills in order to obtain level A2.


Asunto(s)
Crianza de Animales Domésticos/educación , Técnicos de Animales/educación , Educación en Veterinaria , Educación , Ciencia de los Animales de Laboratorio/educación , Personal de Laboratorio Clínico/educación , Crianza de Animales Domésticos/normas , Bienestar del Animal , Animales , Animales de Laboratorio , Educación en Veterinaria/normas , Europa (Continente) , Directrices para la Planificación en Salud , Ciencia de los Animales de Laboratorio/normas , Personal de Laboratorio Clínico/normas
16.
Exp Nephrol ; 2(5): 281-5, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7812733

RESUMEN

Urodilatin is an amino terminally extended form of atrial natriuretic factor (ANF) which is resistant to enzymatic cleavage by renal neutral endopeptidase (NEP: EC 3.4.24.11). The renal effects of infusion into the renal artery of equimolar doses of urodilatin or ANF have been compared following changes in Na status in conscious sheep. In all conditions urodilatin was a more potent natriuretic stimulus than was ANF and the natriuretic response to urodilatin was modulated by sodium status in the same way as the response to ANF: diminished by sodium depletion and enhanced by sodium loading. This study does not support the hypothesis that changes in NEP activity contribute to the modulation of the natriuretic response to ANF which is observed with modification of sodium status.


Asunto(s)
Factor Natriurético Atrial/farmacología , Diuréticos/farmacología , Riñón/metabolismo , Fragmentos de Péptidos/farmacología , Sodio/metabolismo , Animales , Femenino , Tasa de Filtración Glomerular , Riñón/efectos de los fármacos , Riñón/fisiología , Ovinos , Sodio/orina
17.
Clin Exp Pharmacol Physiol ; 24(1): 57-63, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9043806

RESUMEN

1. Ouabain is known to have natriuretic effects only at high doses, and therefore if endogenously produced ouabain has a role in the regulation of sodium excretion, the renal response to ouabain must be increased substantially in certain physiological situations. The aim of this study is to determine whether treatment with the mineralocorticoid, aldosterone, potentiates that natriuretic response to ouabain. 2. Six conscious sheep received renal arterial infusion of either vehicle or aldosterone (3 micrograms/h). Forty hours after commencement of infusion ouabain was infused into the renal artery at 400 micrograms/h for 60 min. A second infusion of ouabain was administered on the 6th day of aldosterone treatment. 3. In the absence of aldosterone, the effects on sodium excretion produced by ouabain infusion at 400 micrograms/h into the renal artery were variable and not statistically significant. Ouabain infusion after 40 h of aldosterone treatment increased sodium excretion from 40 +/- 14 to 676 +/- 69 mumol/min in the second hour following cessation of ouabain infusion (P < 0.001). Ouabain infusion after 6 days of aldosterone treatment increased sodium excretion similarly. Ouabain-stimulated sodium excretion was significantly greater during aldosterone treatment compared to vehicle treatment (P < 0.05). In contrast, no enhancement of effect was observed after acute treatment with aldosterone. 4. These results demonstrate potentiation of the natriuretic response to ouabain infusion by chronic mineralocorticoid treatment and suggest a potential role of endogenous digitalis-like factor in the physiological control of sodium homeostasis.


Asunto(s)
Aldosterona/farmacología , Digoxina , Riñón/efectos de los fármacos , Ouabaína/farmacología , Aldosterona/administración & dosificación , Animales , Cardenólidos , Sinergismo Farmacológico , Femenino , Infusiones Intraarteriales , Riñón/fisiología , Ouabaína/sangre , Arteria Renal , Saponinas/metabolismo , Ovinos , Sodio/metabolismo
18.
Ren Physiol Biochem ; 18(6): 311-20, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8711269

RESUMEN

Evidence exists that an endogenous substance which inhibits (Na+,K+)-ATPase, in a similar manner to the cardiac glycosides, may have important cardiovascular and renal effects. Whilst ouabain or a closely related isomer has been reported to be present in mammalian plasma, renal effects of ouabain occur only at high concentrations. The effect of expansion of blood volume on the renal response to ouabain infusion was examined in conscious sheep. Five sheep with catheters chronically implanted into the renal artery received four treatment combinations in random order: (I) vehicle (0.15 mol l-1 NaCl) infusion; (II) 500 micrograms ouabain infused into the renal artery over 60 min; (III) 500 ml 6% dextran 70 in 0.9% saline infused intravenously, and (IV) the dextran and ouabain treatments together. Treatment with either ouabain or plasma volume expansion produced modest increases in sodium excretion and urine flow. Treatment with ouabain when combined with plasma volume expansion increased sodium excretion from 82 +/- 30 to 880 +/- 203 mumol min-1 and urine flow from 1.9 +/- 1.1 to 7.5 +/- 1.6 ml min-1. This combination of treatments results in a synergistic rather than additive response. This study indicates that under some circumstances the response of the kidney to inhibition of (Na+,K+)-ATPase can be enhanced and, if inhibition can be demonstrated to occur at physiologically relevant concentrations of endogenous digitalis-like factor, would support a possible physiological role for endogenous digitalis-like factor in the regulation of sodium homeostasis.


Asunto(s)
Digoxina , Inhibidores Enzimáticos/farmacología , Natriuresis/efectos de los fármacos , Ouabaína/farmacología , Sustitutos del Plasma/farmacología , Saponinas/farmacología , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Animales , Cardenólidos , Femenino , Infusiones Intravenosas , Ovinos
19.
Clin Exp Pharmacol Physiol Suppl ; 25: S57-60, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9809194

RESUMEN

1. There is considerable evidence for the existence of an endogenous inhibitor of Na+/K(+)-ATPase. The exact physiological nature and role of this postulated agent remains unclear, although it would be predicted that one of its actions would be stimulation of renal sodium excretion. 2. The natriuretic effect of renal arterial infusion of ouabain is relatively slow in onset and is sustained. 3. The natriuresis is not modified by changes in sodium status, unlike the natriuretic effect of atrial natriuretic peptide. 4. The natriuretic action of ouabain is enhanced dramatically by acute volume expansion or chronic mineralocorticoid treatment, which both result in hypokalaemia, hypertension and hypervolaemia. 5. The natriuretic response to small increments in blood pressure is markedly enhanced by treatment with ouabain. 6. We hypothesize that the interaction between the inhibition of Na+/K(+)-ATPase and elevated blood pressure could result in the shedding of sodium in conditions where there are increased levels of circulating endogenous digitalis-like factors.


Asunto(s)
Natriuresis/fisiología , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Animales , Factor Natriurético Atrial/fisiología , Presión Sanguínea/fisiología , Volumen Sanguíneo , Humanos , Ouabaína/farmacología , Sodio/metabolismo
20.
Clin Exp Pharmacol Physiol ; 21(4): 329-33, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7923901

RESUMEN

1. The effect of cyclo(D-Trp-D-Asp-Pro-D-Val-Leu) (or BQ123), a selective ETA receptor antagonist, on the vasoconstrictor and diuretic responses elicited by endothelin-1 (ET-1) was examined in conscious sheep with chronic indwelling renal arterial cannulae. 2. Using low dose close renal arterial infusion, ET-1 has potent effects on the kidney causing a marked decrease in effective renal plasma flow and an increase in urine output and free water clearance in the normally hydrated animal. 3. The vasoconstrictor response to renal arterial infusion of ET-1 at 5 micrograms/h was blunted by renal arterial infusion of the ETA receptor selective antagonist, BQ123 (400 micrograms/h). 4. In contrast, the effect of ET-1 on urine production and free water clearance was not affected by this dose of BQ123. 5. The differential effect of BQ123 on renal blood flow and urine production suggests that these effects of endothelin on the kidney are mediated through different receptor mechanisms.


Asunto(s)
Endotelinas/antagonistas & inhibidores , Endotelinas/farmacología , Riñón/efectos de los fármacos , Péptidos Cíclicos/farmacología , Secuencia de Aminoácidos , Animales , Diuresis/efectos de los fármacos , Antagonistas de los Receptores de Endotelina , Femenino , Riñón/irrigación sanguínea , Datos de Secuencia Molecular , Ovinos , Vasoconstricción/efectos de los fármacos
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