RESUMEN
When elderly become frail and in need for complex care, they can no longer live independently at home and may be admitted to nursing homes. Various studies have shown that oral health in this population is remarkably poor, which may lead to distressing situations and impacts quality of life. A variety of definitions or descriptions for oral health is used. Without a uniform parameter, it is impossible to determine whether oral health in institutionalized elderly is actually improving or deteriorating over time, as well as the effect of (preventive) interventions. In search for an adequate and clinically applicable parameter to determine oral health in this specific patient group, this scoping review aims to give an overview of the currently used parameters for determining oral health in institutionalized elderly. Ninety different parameters were identified, and 50 parameters were solely used by one study. Only 4 parameters were frequently used (in > 20 studies). The relevance of these parameters for this specific patient group is discussed. To aid the planning and commissioning of future research and patient care, there is an urgent need for an adequate and uniform parameter for oral health determination in institutionalized elderly.
Asunto(s)
Salud Bucal , Calidad de Vida , Humanos , Anciano , Casas de Salud , Anciano FrágilRESUMEN
Many frail older adults have a poor oral health: unrestorable broken teeth and root remnants with open root canals, commonly associated with periapical and periodontal inflammation, are often seen. Improving oral health in this growing group of frail older adults is a considerable challenge for dental care professionals. Dentists are often uncertain how to deal with root remnants and unrestorable broken teeth in psychogeriatric and/or medically compromised frail older adults. Decisions about the extraction or retention of root remnants should not only be made on the basis of preventing pain and inflammation, but also on the course of disease, life expectancy, cooperation, laws and regulations and other factors that are an issue in geriatric patients but not in regular (healthy) patients. To help oral health care professionals in their treatment choice for this complex patient group, a decision tree was developed in which both root and patient-related factors were included.
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Anciano Frágil , Salud Bucal , Anciano , Humanos , Estado de Salud , Inflamación , Esperanza de Vida , Cuidado Dental para AncianosRESUMEN
Cross-sectional studies have shown that elderly with a natural dentition or implant-retained overdenture have better general health outcomes than elderly with conventional dentures. It is not known whether these findings would be confirmed in longitudinal studies of such groups of elderly. Therefore, in this study a large group of elderly (aged 75 and over) with a natural dentition (n = 143,199), an implant-retained overdenture (n = 6,503) or conventional denture (n=18,420) were followed over a period of 8 years. Elderly with conventional dentures had chronic conditions more often, used more medication and had higher healthcare costs. Remarkably, the general health outcomes of elderly with an implant-retained overdenture declined over the period of 8 years. At the time the implant-retained overdenture was placed, their general health profile seemed comparable to that of elderly with a natural dentition, but as time progressed it declined to the level of elderly with conventional dentures.
Asunto(s)
Implantes Dentales , Prótesis Dental de Soporte Implantado , Anciano , Estudios Transversales , Atención Odontológica , Prótesis de Recubrimiento , Costos de la Atención en Salud , Humanos , Mandíbula , Satisfacción del PacienteRESUMEN
Although ample research has been done on implant-retained overdentures, little is known about the age, health aspects and socio-economic status of patients receiving an implant-retained overdenture for the first time. Therefore, a big data study was set up, in cooperation with Vektis (a Dutch national database for all insured and claimed healthcare), with the aim of investigating the aspects mentioned earlier in patients who received implant-retained overdentures between 2009 and 2016. The study showed that these overdentures were predominantly made for the lower jaw, using a bar attachment system. It also showed they were mainly used for relatively young (55- to 75-year-olds) and healthy patients. It was concluded that relatively few implants are placed to support implant-retained overdentures in patients over 85 years of age and in those with diabetes mellitus, although neither are contraindicated.
Asunto(s)
Implantes Dentales , Arcada Edéntula , Estudios Transversales , Prótesis Dental de Soporte Implantado , Retención de Dentadura , Prótesis de Recubrimiento , Humanos , MandíbulaRESUMEN
BACKGROUND: It is unclear how many community-dwelling elderly (≥75 years) experience oral health problems (e.g. pain, dry mouth, chewing problems) and how they manage their dental care needs. This study aimed to assess self-reported oral health problems in elderly who are frail or have complex care needs, and their ability to organize dental care when reporting oral pain. METHODS: Three thousand five hundred thirty-three community-dwelling elderly participating in the "Embrace" project were asked to complete questionnaires regarding oral status and oral health problems. Frailty was assessed with the Groningen Frailty Indicator (GFI). Intermed for Elderly Self-Assessment (IM-E-SA) was used to determine complexity of care needs. Next, elderly who reported oral pain were interviewed about their oral pain complaints, their need for dental care, and their ability to organize and receive dental care. For statistical analyses Chi2-tests and the one-way ANOVA were used. RESULTS: One thousand six hundred twenty-two elderly (45.9%) completed the questionnaires. Dry mouth (11.7%) and oral pain (6.2%) were most frequently reported. Among the elderly reporting oral pain, most were registered at a local dentist and could go there when needed (84.3%). Robust elderly visited the dentist independently (87%), frail (55.6%) and complex (26.9%) elderly more often required assistance from caregivers. CONCLUSIONS: Dry mouth and oral pain are most reported oral health problems among community-dwelling elderly. Elderly with complex care needs report most oral health problems. In case an elderly seeks dental treatment to alleviate an oral pain complaint, most elderly in this study were able to organize dental care and transport to the dentist. Frail and complex elderly often need assistance from caregivers to visit the dentist. Therefore caretakers should keep in mind that when frailty progresses, visiting a dentist may become more and more difficult and the risk for poor oral health increases.
Asunto(s)
Cuidado Dental para Ancianos/estadística & datos numéricos , Atención Odontológica/estadística & datos numéricos , Salud Bucal , Anciano , Anciano de 80 o más Años , Estudios Transversales , Encuestas de Salud Bucal , Femenino , Anciano Frágil , Evaluación Geriátrica , Servicios de Salud para Ancianos , Humanos , Vida Independiente , AutoinformeRESUMEN
Oral health in frail older people is often poor. There are a number of reasons for this, such as increased morbity and decreased motivation for (self) care. Good oral health is, however, very important. Studies have revealed poor oral health to cause or aggravate several medical and psychological problems. Illness and medication can, in turn, damage oral health. Oral health among the elderly should therefore be carefully monitored and maintained. This requires multidisciplinary and interprofessional collaboration on the part of healthcare professionals and others involved. Such collaboration is now still very limited; hardly anything has been written about how such collaboration in the area of oral care for frail older people should or could be organised. This article provides an overview of the possibilities and the relevant factors in the area of oral care for the elderly in promoting collaboration among healthcare professionals and others involved. All of this is under the banner of 'united we stand'.
Asunto(s)
Anciano Frágil , Salud Bucal , Anciano , Anciano de 80 o más Años , Personal de Salud , Humanos , AutocuidadoRESUMEN
In the coming decades the western world will experience a double ageing of its population; there will be an increase in both the number of older people and the average age. The increase in life expectancy will also mean more and more older people who suffer from multiple systemic diseases that are treated with medications. At this moment, 45% of those over 65 use 5 or more medications and 20% of those over 75 use as many as 10 or more. The more medications used, the greater the risk of side effects and therefore oral side effects, like symptoms of dry mouth or the development of candidiasis, angioedema, gingival hyperplasia, lichenoid reaction of the oral mucosa, dysgeusia, halitosis and osteonecrosis. Considering the wide range of oral side effects, it is important for dentists to be well aware of the medications being used by older patients as well as having a thorough knowledge of their oral side effects.
Asunto(s)
Cuidado Dental para Ancianos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Enfermedades de la Boca/epidemiología , Enfermedades Periodontales/epidemiología , Enfermedades Dentales/epidemiología , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Femenino , Humanos , Esperanza de Vida , Masculino , Mucosa Bucal , Xerostomía/epidemiologíaRESUMEN
Gastrointestinal (GI) nematode infections are considered among one of the toughest challenges sheep farmers face worldwide. Control still is largely based on the use of anthelmintics, but anthelmintic resistance is becoming rampant. To facilitate implementation of alternative nematode control strategies and to reduce anthelmintic usage, the purpose of this study was twofold: (i) to gain insight in common practices, knowledge gaps and perceptions of farmers regarding nematode control, and (ii) to provide foci of attention for improving parasite control practices and transfer of knowledge within the sheep husbandry. An internet-based questionnaire was made available to all sheep farmers pertaining to the year 2013, resulting in 450 entered questionnaires for analysis. The two most important nematodes mentioned, were Haemonchus contortus and, to a lesser extent, Nematodirus battus. Of all respondents, 25.6% said they did not have any worm problems. Of these, almost a third did notice clinical signs that can be related to worm infections and about three quarters did use anthelmintics. Overall, clinical symptoms mentioned by farmers matched the worm species they identified as the cause of problems. Ewes and lambs were treated up to 6 times in 2013. On average, ewes were treated 1.53 and lambs 2.05 times. Farmers who treated their ewes more often, also treated their lambs more often (P<0.001). Both ewes and lambs were frequently treated based on fixed moments such as around lambing, at weaning and before mating, rather than based on faecal egg counts. Treatments based on faecal egg counts were practiced, but on a minority of the farms (32.7%). The majority of the farms (75.6%) did not leave 2-5% of the sheep within a flock untreated. About 74% of farmers keep newly purchased animals quarantined for at least 10days, but some (13.4%) leave quarantined animals untreated nor check faecal egg counts. Of farmers who do treat their quarantined animals, just 12.6% check the efficacy of the treatment. Slightly over 40% of the respondents said they did not experience bottlenecks in parasite control. Yet, over half of these said having problems with worm infections, over half did see clinical signs related to worm infections and over three quarters used anthelmintics. Within the group of farmers experiencing difficulties in parasite control, the most often mentioned bottleneck concerned pasture management (75.8%). When asking farmers for solutions, 90% of all respondents indicated they are willing to adjust their pasture management. Farmers are also interested in other methods to reduce the risk of worm infections, such as possibilities to enhance the immune system of sheep in general (71%), to increase specific genetic resistance to worms and to apply anti-parasite forages, both about 40%. Results of this study gave the following potential foci of attention: (1) making complex scientific knowledge more accessible to farmers through simple tools and applicable in the daily farming process; (2) changing the mindset of farmers about their current worm control practices, i.e. breaking long-standing habits such as treating ewes and lambs at fixed moments rather than based on actual worm infection monitoring data; (3) demonstrating effective pasture rotation schemes on specific farms and using these in extension work; (4) making farmers more aware that checking anthelmintic efficacy is important; (5) improving quarantine procedures; (6) creating a wider array of applicable alternative control measures from which individual farmers can choose what fits them most; and finally, (7) improving mutual understanding among farmers, veterinary practitioners and parasitologists alike.
Asunto(s)
Agricultores , Conocimientos, Actitudes y Práctica en Salud , Helmintiasis Animal/parasitología , Enfermedades de las Ovejas/parasitología , Animales , Antihelmínticos/uso terapéutico , Cruzamiento , Recolección de Datos , Femenino , Predisposición Genética a la Enfermedad , Helmintiasis Animal/epidemiología , Helmintiasis Animal/prevención & control , Masculino , Países Bajos/epidemiología , Ovinos , Enfermedades de las Ovejas/epidemiología , Enfermedades de las Ovejas/genética , Enfermedades de las Ovejas/prevención & controlRESUMEN
Injection of the N-methyl-D-aspartate receptor agonist quinolinate, or N-methyl-D-aspartate itself, into the rat brain produces neurodegeneration which can be prevented by N-methyl-D-aspartate receptor antagonists administered up to 5 h after excitotoxin injection. The present study was designed to investigate aspects of the mechanisms involved in this delayed form of neurodegeneration. Following its injection into the rat striatum, extracellular levels of [3H]quinolinate were monitored using a microdialysis probe located 1 mm from the site of injection. Peak concentrations were observed 10-20 min after injection and [3H]quinolinate levels decayed in a biexponential fashion, the initial component having an apparent t1/2 of 13.7 +/- 5.2 min (n = 3). Estimations of the extracellular concentrations of quinolinate after an injection of 200 nmol indicated a peak level of 13.7 +/- 6.0 mM (n = 3) at 10-20 min which declined to 1.2 +/- 0.13 mM (n = 3) by 2 h and substantial levels were present up to 5 h, the period over which N-methyl-D-aspartate receptor antagonists are effective in this model. Administration of dizocilpine at 1, 2, 3 or 5 h after injection of 100, 200 or 400 nmol quinolinate resulted in a similar temporal profile of neuroprotection, as assessed by measuring the activities of choline acetyltransferase and glutamate decarboxylase in striatal homogenates, which was independent of the degree of neurodegeneration produced by the different excitotoxin doses. Overall, these results suggest that the neuronal degeneration caused by quinolinate in vivo is critically dependent upon events occurring after the initial peak of excitoxin levels in the extracellular space.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Convulsivantes/toxicidad , Cuerpo Estriado , Degeneración Nerviosa/fisiología , Ácidos Quinolínicos/toxicidad , Antagonistas Adrenérgicos alfa/farmacología , Animales , Anticonvulsivantes/farmacología , Convulsivantes/administración & dosificación , Diálisis , Diazepam/farmacología , Maleato de Dizocilpina/farmacología , Glutamato Descarboxilasa/metabolismo , Haloperidol/farmacología , Ácido Iboténico/farmacología , Inyecciones , Masculino , Degeneración Nerviosa/efectos de los fármacos , Ácidos Pipecólicos/farmacología , Piperazinas/farmacología , Piperidinas/farmacología , Ácido Quinolínico , Ácidos Quinolínicos/administración & dosificación , Ratas , Ratas Endogámicas , Técnicas EstereotáxicasRESUMEN
Regulation of the developing nervous system involves attraction, guidance and modification of innervating neurons by target cells through diffusible and membrane-related factors. The trophic effects from specific cell types remain to be investigated and characterized. In a series of experiments in which human fetal mesencephalic dopaminergic cells were co-cultured with target or non-target neurons or glial cells in direct or contiguous contact, we demonstrate that striatal glial cells (target-derived glia) can enhance dopaminergic neuron survival by up to 400% compared to either non-target cell co-cultures or mesencephalic controls. When in direct contact with striatal neurons, a greater proportion of dopaminergic neurons had a more differentiated morphology. The enhancement of dopaminergic neuron survival by target-derived glia appears to be mediated both by direct contact, possibly through target membrane-specific phenomena, and by diffusible substances, whereas non-target glia appear to exert the trophic effects predominantly through the latter mechanism. The finding that target neurons influence mainly dopaminergic neuron differentiation and target glia their survival indicates multiple, target cell type-specific regulation of innervating neuron development. These findings also have relevance to the establishment of neuronal cultures for neural transplantation.
Asunto(s)
Comunicación Celular , Cerebelo/fisiología , Cuerpo Estriado/citología , Dopamina/metabolismo , Mesencéfalo/citología , Neuroglía/fisiología , Neuronas/citología , Neuronas/fisiología , Diferenciación Celular , Supervivencia Celular , Células Cultivadas , Cerebelo/citología , Cuerpo Estriado/fisiología , Feto , Humanos , Mesencéfalo/fisiología , Neuronas/efectos de los fármacos , Potasio/farmacologíaRESUMEN
Segmented filamentous bacteria (SFB) are known to stimulate the mucosal immune system. Here, the effect of SFB on oral booster immunization with ovalbumin was investigated. Mice mono-associated with SFB or Clostridium innocuum were sensitized by intraperitoneal administration of 100 micrograms ovalbumin with Freunds complete adjuvant. After 4 weeks, mice received 80 mg ovalbumin orally. A maximum IgA response was found 5 days after this booster immunization. Comparison of mice with SFB and mice with C. innocuum revealed a much higher level of IgA in the gut lumen and more IgA secreting cells in the lamina propria of the SFB-associated mice. However, no differences between both groups of animals were found in specific levels of IgA secreting cells or luminal IgA against ovalbumin. It is concluded that there is no enhancing effect of SFB after booster immunization when mice are primed intraperitoneally with ovalbumin.
Asunto(s)
Clostridium/inmunología , Inmunización Secundaria , Inmunoglobulina A/inmunología , Mucosa Intestinal/inmunología , Ovalbúmina/inmunología , Administración Oral , Animales , Especificidad de Anticuerpos , Células Productoras de Anticuerpos , Inmunoglobulina A/análisis , Intestinos/inmunología , Intestinos/microbiología , Masculino , RatonesRESUMEN
The appearance of segmented, filamentous bacteria (SFBs) in the small bowel of mice is influenced by the composition of the diet, but the dietary components responsible are not known. The addition of ground, whole Phaseolus vulgaris to a natural-ingredient diet at the expense of part of the skim milk powder, ground barley and wheat middlings components, caused an increase of the colonization of the mouse small bowel by SFBs. This effect was not seen when whole Phaseolus was added to a purified diet at the expense of part of the casein, corn oil, coconut fat, corn starch, dextrose and cellulose components. In an attempt to identify the fraction of Phaseolus that might contain SFB-inducing substances, the skin and kernel fraction of the bean were added to the natural-ingredient diet. The skin and kernel fraction were found to be as effective in inducing SFB appearance as was whole Phaseolus.
Asunto(s)
Alimentación Animal , Bacterias/crecimiento & desarrollo , Fabaceae , Intestino Delgado/microbiología , Plantas Medicinales , Animales , Bacterias/aislamiento & purificación , Factores Biológicos/análisis , Recuento de Colonia Microbiana , Femenino , Ratones , Reproducibilidad de los ResultadosRESUMEN
Segmented, filamentous bacteria (SFBs) form a group of bacteria with similar morphology and are identified on the basis of their morphology only. The relationships of these organisms are unclear as the application of formal taxonomic criteria is impossible currently due to the lack of an in vitro technique to culture SFBs. The intestine of laboratory animals such as mice, rats, chickens, dogs, cats and pigs is known to harbour SFBs. To see whether this extends to other animal species, intestines from 18 vertebrate species, including man, were examined. SFBs were detected with light microscopy in the cat, dog, rhesus monkey, crab-eating macaque, domestic fowl, South African claw-footed toad, carp, man, laboratory mouse and rat, wood mouse, jackdaw and magpie. These results suggest that non-pathogenic SFBs are ubiquitous in the animal kingdom. Among apparently identical animals, there was considerable variation in the degree of SFB colonization. It is suggested that SFB colonization could serve as a criterion of standardization of laboratory animals.
Asunto(s)
Animales de Laboratorio/microbiología , Bacterias/aislamiento & purificación , Intestinos/microbiología , Adulto , Anciano , Animales , Bacterias/ultraestructura , Gatos , Cricetinae , Perros , Femenino , Cobayas , Humanos , Masculino , Ratones , Persona de Mediana Edad , Conejos , RatasRESUMEN
Segmented, filamentous bacteria (SFBs) are autochthonous, apathogenic inhabitants of the ileum of various animal species. Outbred Swiss (Cpb:SE) mice have significantly higher degrees of SFB colonization than do inbred BALB/c mice. The present studies were carried out to identify determinants of this strain difference. In a cross-fostering experiment it was shown that SFB colonization of the pups is determined by the strain of the pups themselves rather than by the strain of the nursing dam. Thus, maternal effects may not be involved in SFB colonization. In a cross-infecting experiment using germ-free and SFB-positive animals of the two mouse strains, it was found that ileal SFB colonization is determined by host characteristics rather than by origin of the SFBs. Thus, SFBs that are specific for a given mouse strain may not exist in the two strains of mice. It is concluded that the mouse strain difference in SFB colonization is determined by host characteristics, which probably have a genetic basis.
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Bacterias/crecimiento & desarrollo , Íleon/microbiología , Ratones Endogámicos BALB C/microbiología , Ratones/microbiología , Animales , Animales Recién Nacidos , Femenino , Vida Libre de Gérmenes , Masculino , Organismos Libres de Patógenos EspecíficosAsunto(s)
Aves/microbiología , Cloaca/microbiología , Animales , Bacterias/aislamiento & purificación , Femenino , MasculinoRESUMEN
The N-methyl-D-aspartate (NMDA) receptor is thought to contain several distinct binding sites that can regulate channel opening. In the present experiments, the effects of ligands for these sites have been examined on [3H]MK-801 binding to a soluble receptor preparation, which had been passed down a gel filtration column to reduce the levels of endogenous small-molecular-weight substances. Glycine site agonists, partial agonists, and antagonists gave effects similar to those observed in membranes [EC50 values (in microM): glycine, 0.31; D-serine, 0.20; D-cycloserine, 1.46; (+)-HA-966, 4.06; and 7-chlorokynurenic acid, 1.81]. Spermine and spermidine enhanced [3H]MK-801 binding to the soluble receptor preparation (EC50, 4.3 and 20.1 microM, respectively), whereas putrescine and cadaverine gave small degrees of inhibitions. When spermine and spermidine were tested under conditions where [3H]MK-801 binding approached equilibrium, their ability to enhance [3H]MK-801 binding was much reduced, a result suggesting that the polyamines increase the rate to equilibrium. Putrescine antagonised the effects of spermine. Ifenprodil reduced [3H]MK-801 binding under both equilibrium and nonequilibrium conditions, although the high-affinity component of inhibition described in membranes was not observed. Ifenprodil antagonised spermine effects in an apparently noncompetitive manner. Desipramine was able to give total inhibition of specific [3H]MK-801 binding under nonequilibrium conditions with an IC50 of 4 microM, and this value was unaltered when [3H]MK-801 binding was allowed to reach equilibrium. These results suggest that the sites mediating the effects of glycine and its analogues, polyamines and desipramine are integral components of the NMDA receptor protein.
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Encéfalo/metabolismo , Maleato de Dizocilpina/metabolismo , Glicina/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animales , Sitios de Unión , Cromatografía en Gel , Desipramina/farmacología , Ligandos , Masculino , Piperidinas/farmacología , Poliaminas/farmacología , Ratas , Ratas Endogámicas , Solubilidad , TritioRESUMEN
The microflora of the gastro-intestinal tract of dystrophic BIO 8262 Nij Syrian hamsters and Kun:Sh Syrian hamsters as controls was investigated by means of culturing techniques and scanning electron microscopy. The oesophagus, forestomach, stomach, small intestine, coecum and faeces were assessed for the presence of Enterobacteriaceae, Staphylococci, Lactobacilli, Streptococci, Clostridia, Bacteroides and yeasts. The normal hamsters showed low levels of yeasts in the oesophagus, forestomach and stomach; yeasts were not present in the other compartments. Relatively low levels of Staphylococci and Enterobacteriaceae were found in all gut segments; also Bacteroides was found in low levels in the upper part of the gut. The other groups of bacteria showed relatively high levels in all segments. In dystrophic BIO 8262 Nij hamsters no Enterobacteriaceae and yeasts have been detected in the gut. Scanning electron microscopy showed no difference in adhesion between both hamsters strains.
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Bacterias/crecimiento & desarrollo , Cricetinae , Sistema Digestivo/microbiología , Mesocricetus , Distrofia Muscular Animal/microbiología , Enfermedades de los Roedores/microbiología , Animales , Recuento de Colonia Microbiana , Femenino , Masculino , Levaduras/crecimiento & desarrolloRESUMEN
In a cross-over trial, five healthy dogs were fed a dry food without or with 1% (w/w) oligofructose to assess any oligofructose-induced effects on the faecal bacterial profile, nitrogen excretion and mineral absorption. The diets were given for a period of 3 weeks. Oligofructose feeding significantly raised the number of Bifidobacteria, Streptococci and Clostridia in faeces. The numbers of faecal anaerobic and aerobic bacteria were raised after ingestion of oligofructose. The faecal pH was unchanged. There was no effect of oligofructose feeding on the route of nitrogen excretion which was associated with a lack of effect on faecal ammonium and urinary urea excretion. It is suggested that the absence or presence of an effect of oligofructose on urinary and faecal nitrogen excretion depends on the background composition of the diet, in particular the content of non-digestible, fermentable carbohydrates. In the diets used, the content of non-digestible, fermentable carbohydrates was not measured. Both apparent magnesium and calcium absorption were significantly raised by oligofructose feeding, but phosphorus absorption was unaffected. The data presented may contribute to the qualification of the use of oligofructose in dog foods.
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Alimentación Animal , Perros/metabolismo , Heces/microbiología , Minerales/metabolismo , Nitrógeno/metabolismo , Oligosacáridos/administración & dosificación , Animales , Bifidobacterium/crecimiento & desarrollo , Bifidobacterium/aislamiento & purificación , Calcio/metabolismo , Clostridium/crecimiento & desarrollo , Clostridium/aislamiento & purificación , Estudios Cruzados , Suplementos Dietéticos , Heces/química , Femenino , Absorción Intestinal , Magnesio/metabolismo , Masculino , Fósforo/metabolismo , Streptococcus/crecimiento & desarrollo , Streptococcus/aislamiento & purificación , Orina/químicaRESUMEN
We replaced the coding region of the murine 5-hydroxytryptamine (5-HT)1B receptor by the human 5-HT1B receptor using homologous recombination in embryonic stem cells and generated and characterized homozygous transgenic mice that express only the human (h) 5-HT1B receptor. The distribution patterns of h5-HT1B and murine (m) 5-HT1B receptor mRNA and binding sites in brain sections of transgenic and wild-type mice were identical as measured by in situ hybridization histochemistry and radioligand receptor autoradiography. When measured in parallel under identical conditions, the h5-HT1B receptor expressed in mouse brain had the same pharmacological characteristics as that in human brain. Stimulation by 5-HT1B agonists of [35S]guanosine-5'-O-(3-thio)triphosphate binding in brain sections demonstrated the functional coupling of the h5-HT1B receptor to G proteins in mouse brain. In tissue slices from various brain regions, electrically stimulated [3H]5-HT release was not modified by 5-HT1B agonists in tissue from either transgenic and wild-type mice; a 5-HT1B antagonist enhanced electrically stimulated [3H]5-HT release in wild-type mouse brain, but was ineffective in the transgenics. The centrally active 5-HT1A/5-HT1B agonist RU24969 induced hypothermia but did not increase locomotor activity in the transgenic mice. The ineffectiveness of RU24969 in the transgenic mice could be due to the lower affinity of the compound for the h5-HT1B receptor compared with the m5-HT1B receptor. The present study demonstrates a complete replacement of the mouse receptor by its human receptor homolog and a functional coupling to G proteins. However, modulation of [3H]5-HT release could not be shown. Furthermore, behavioral effects were not clearly observed, which may be due to a lack of appropriate tools.
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Receptores de Serotonina/genética , Animales , Benzamidas/farmacocinética , Benzopiranos/farmacocinética , Sitios de Unión , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Expresión Génica , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Humanos , Hipotermia/inducido químicamente , Hibridación in Situ , Indoles/farmacología , Ratones , Ratones Transgénicos , Actividad Motora/efectos de los fármacos , Piperidonas/farmacología , Propilaminas/farmacocinética , Piridinas/farmacocinética , Piridinas/farmacología , Pirimidinas/farmacocinética , Pirroles/farmacología , ARN Mensajero/genética , Receptor de Serotonina 5-HT1B , Receptores de Serotonina/efectos de los fármacos , Recombinación Genética , Serotonina/análogos & derivados , Serotonina/metabolismo , Serotonina/farmacología , Antagonistas de la Serotonina/farmacocinética , Agonistas de Receptores de Serotonina/farmacología , Compuestos de Espiro/farmacología , TritioRESUMEN
In cattle chronically infected with T. vivax Y 58, a mononuclear pancarditis with extravascular trypanosomes is described. It has been considered as a local immune response to these extravascular trypanosomes. No autoantibodies for heart tissue have been found.