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1.
Sci Rep ; 9(1): 2738, 2019 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-30804494

RESUMEN

Diseases of the gastrointestinal tract due to changes in the bacterial flora have been described with increasing incidence in the European brown hare. Despite extensive demographic and phylogeographic research, little is known about the composition of its gut microbiota and how it might vary based on potential environmental or host factors. We analysed the intestinal and faecal microbiota of 3 hare populations by Illumina MiSeq 16S rRNA gene amplicon sequencing. The phyla and OTU abundance composition differed significantly between intestinal and faecal samples (PERMANOVA: P = 0.002 and P = 0.031, respectively), but in both sample types Firmicutes and Bacteroidetes dominated the microbial community composition (45.51% and 19.30% relative abundance). Intestinal samples contained an enrichment of Proteobacteria compared with faecal samples (15.71-fold change, P < 0.001). At OTU level, a significant enrichment with best BLAST hits to the Escherichia-Shigella group, Eubacterium limosum, Sphingomonas kyeonggiensis, Flintibacter butyricus and Blautia faecis were detected in intestinal samples (P < 0.05). In our statistical model, geographic location and possibly associated environmental factors had a greater impact on the microbiota composition than host factors. Population had a significant effect on the composition of abundant intestinal and faecal OTUs, and on the abundance of potential pathogenic bacteria of the family Enterobacteriaceae, regularly associated with intestinal dysbiosis in hares, in faecal samples. Our study is the first to describe the microbiota in brown hares and provides a foundation to generate hypothesis aiming to test the role of gut health in population fluctuations of the species.


Asunto(s)
Microbioma Gastrointestinal , Liebres/microbiología , Animales , Bacterias/genética , Bacterias/aislamiento & purificación , Bacteroidetes/genética , Bacteroidetes/aislamiento & purificación , Heces/microbiología , Femenino , Firmicutes/genética , Firmicutes/aislamiento & purificación , Masculino , ARN Ribosómico 16S/genética
2.
J Comp Pathol ; 138(2-3): 63-71, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18295780

RESUMEN

This report describes the development of a diagnostic method for protozoal infections of the gastrointestinal tract of captive snakes, based on chromogenic in-situ hybridization with probes designed for the detection of 18S rRNA genes from Cryptosporidium spp., Entamoeba spp., Entamoeba invadens and Monocercomonas spp. The specificity of the probes was confirmed with the help of parasitic cultures and gene sequence analysis. The probes gave clear positive signals. Of 182 snakes examined, seven were positive with the Cryptosporidium probe, 13 with the Entamoeba probe (of which nine were also positive with the E. invadens probe), and 34 with the Monocercomonas probe.


Asunto(s)
Cryptosporidium/aislamiento & purificación , Entamoeba/aislamiento & purificación , Tracto Gastrointestinal/parasitología , Enfermedades Parasitarias en Animales/diagnóstico , Trichomonadida/aislamiento & purificación , Animales , Cryptosporidium/genética , Cryptosporidium/fisiología , ADN Protozoario/análisis , Entamoeba/genética , Entamoeba/fisiología , Mucosa Gástrica/parasitología , Mucosa Gástrica/patología , Hibridación in Situ/veterinaria , Mucosa Intestinal/parasitología , Mucosa Intestinal/patología , Hígado/parasitología , Hígado/patología , Reacción en Cadena de la Polimerasa/veterinaria , Análisis de Secuencia de ADN/veterinaria , Trichomonadida/genética , Trichomonadida/fisiología
3.
Org Lett ; 2(19): 2943-6, 2000 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-10986078

RESUMEN

A linear bis secondary dialkylammonium ion-containing scaffold-based upon an anthracenyl core-has been synthesized. It has been demonstrated that it is possible to dock either one or two dibenzo[24]crown-8 (DB24C8) macrocycles onto this scaffold to afford either a [2]- or [3]pseudorotaxane, respectively. In solution, the association constants for the formation of each of these species has been quantified by employing (1)H NMR spectroscopy, and both species survive in the "gas phase" as evidenced by FAB mass spectrometry. Additionally, the X-ray crystal superstructure of the [3]pseudorotaxane has been determined.

4.
Org Lett ; 2(19): 2947-50, 2000 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-10986079

RESUMEN

Dipyrido[24]crown-8 (DP24C8) has been synthesized and shown to form [2]pseudorotaxanes spontaneously with dibenzylammonium ions. These complexes, which have been demonstrated by (1)H NMR spectroscopy to form faster in solution than when the macrocyclic polyether is dibenzo[24]crown-8 (DB24C8), are also stronger than their DB24C8 counterparts. One of the [2]pseudorotaxanes has been used to construct a [2]rotaxane (see above) comprising a dumbbell-shaped component based on a dibenzylammonium ion which is encircled by a DP24C8 macrocycle and terminated by (triphenylphosphonium)methyl stoppers.

5.
Cancer Treat Res ; 82: 211-9, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8849952

RESUMEN

Intraoperative intrapeitoneal hyperthermic chemoperfusion (IHCP) offers the following advantages: uniform distribution of heat and drugs at a high concentration in the whole intraperitoneal cavity, heat as a cytotoxic agent itself, and heat as a biomodulator of chemotherapy. Twenty-five patients suffering from diffuse and gross peritoneal carcinomatosis were enrolled into a phase II study to evaluate the feasibility and the efficacy of IHCP. IHCP was carried out with 10 micrograms mitomycin C/ml perfusate in the case of gastrointestinal malignancies or with 50 micrograms cisplatin/ml perfusate in the case of ovarian cancer with malignant ascites. Thirty-two courses of IHCP in 25 patients were eligible in for study of side effects. One patient suffered severe hematologic toxicity, WHO grade 4; two patients suffered severe impairment of renal function, WHO grade 3. Twenty-one patients were eligible for study of the response. Fifteen were classified as having a "favorable clinical response" and in three of them a pathohistologic complete remission was achieved. In only four patients was peritoneal carcinomatosis not influenced by the therapy. Ascites disappeared in 16 out of 19 patients. Tumor markers that were elevated preoperatively in 16 patients returned to normal values in 10 patients postoperatively and dropped more than 50% in three more patients. A remarkable improvement in quality of life was observed in patients who responded to the therapy.


Asunto(s)
Antineoplásicos/administración & dosificación , Hipertermia Inducida , Neoplasias Peritoneales/terapia , Adulto , Anciano , Antineoplásicos/efectos adversos , Terapia Combinada , Humanos , Persona de Mediana Edad
6.
Naunyn Schmiedebergs Arch Pharmacol ; 325(3): 259-69, 1984 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6328334

RESUMEN

The mechanism of the positive inotropic effect of a benzimidazole-pyridazinone, UD-CG 115, was analysed in the isolated guinea-pig papillary muscle contracting isometrically at a frequency of 0.2 Hz. UD-CG 115 produced a slowly developing and poorly reversible positive inotropic effect increasing with concentration (3-300 mumol/l). The effect amounted to 30 and 74% of the maximum inotropic effect of a standard, dihydroouabain, at 34 and 300 mumol/l, respectively. Low concentrations shortened and 300 mumol/l UD-CG 115 significantly prolonged the duration of contraction. The enhancement of the maximum rate of relaxation, S2, was intermediate between those produced by isoprenaline and dihydroouabain, respectively. UD-CG 115 prolonged the duration of the transmembrane action potential (90% repol .) by up to 22% at 300 mumol/l, whereas an equieffective concentration of isoprenaline did not consistently alter action potential duration. UD-CG 115 increased Vmax and overshoot, and prolonged the duration, of slow action potentials elicited at 24 mmol/l [K]0. The inotropic potency of UD-CG 115 was not significantly changed by reserpine pretreatment of the guinea pig or by the presence of 1 mumol/l(-)-propranolol, 3 mumol/l phentolamine or 10 mumol/l cimetidine. Neither was it reduced by 10 mumol/l TTX. The inotropic effect of 100 mumol/l UD-CG 115 remained unchanged when [K]0 was elevated from 3.2 to 12.0 mmol/l. A sarcolemmal preparation of guinea- pig ventricular Na,K-ATPase was only slightly inhibited by the highest concentration of UD-CG 115.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Cardiotónicos/farmacología , AMP Cíclico/metabolismo , Contracción Miocárdica/efectos de los fármacos , Músculos Papilares/fisiología , Inhibidores de Fosfodiesterasa/farmacología , Piridazinas/farmacología , Potenciales de Acción/efectos de los fármacos , Animales , Carbacol/farmacología , Cardiotónicos/antagonistas & inhibidores , Cimetidina/farmacología , Femenino , Cobayas , Histamina/farmacología , Técnicas In Vitro , Isoproterenol/farmacología , Masculino , Músculos Papilares/metabolismo , Propranolol/farmacología , Piridazinas/antagonistas & inhibidores , Reserpina/farmacología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Estimulación Química
7.
J Inorg Biochem ; 91(3): 481-6, 2002 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-12175941

RESUMEN

The effects of pH on the calcium phosphate phase, of Tris and of amino acids, such as aspartic acid, glutamic acid, and serine on hydroxyapatite formation and morphology, were studied in double diffusion experiments. In this system, hydroxyapatite was only formed when the pH was around 7.4 or higher for the duration of the reaction. A decrease in pH resulted in the transformation of hydroxyapatite to octacalcium phosphate. Amino acids and Tris or the buffering capacity of Tris have an effect on the morphology of the synthetic hydroxyapatite. The presence of the additive results in spheres consisting of needles, blades or plates depending on the reaction system.


Asunto(s)
Aminoácidos/química , Durapatita/química , Gelatina/química , Ácido Aspártico , Fosfatos de Calcio , Geles , Ácido Glutámico , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo , Serina , Termodinámica , Trometamina , Difracción de Rayos X
8.
Wien Klin Wochenschr ; 102(9): 274-6, 1990 Apr 27.
Artículo en Alemán | MEDLINE | ID: mdl-2165340

RESUMEN

In a prospective phase II study 15 patients suffering from anaplastic thyroid carcinoma or thyroid sarcoma were treated by surgery and chemotherapy. Chemotherapy varied according to age of the patient and histological subtype of the tumour. The following regimen was used: 100 mg/m2 BSA CDDP, 20 mg/m2 mitoxantrone and 1.5 mg/m2 vincristine. 10 patients responded to chemotherapy, 4 of whom had a complete response. Responders showed a longer mean and median survival time (20.8 months versus 4.5 ms, 15.5 ms vs. 3.8 ms, respectively) than non-responders. In the group responding to chemotherapy no evidence of metachronous metastases was found. Local recurrence was absent only in the patients showing a complete response. Anaplastic carcinomas with areas of differentiated thyroid carcinoma and small cell carcinomas (after exclusion of malignant lymphoma of the thyroid) showed a higher response rate to chemotherapy than spindle or giant cell carcinoma or thyroid sarcoma.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma/tratamiento farmacológico , Neoplasias de la Tiroides/tratamiento farmacológico , Anciano , Carcinoma/cirugía , Carcinoma de Células Pequeñas/tratamiento farmacológico , Cisplatino/administración & dosificación , Terapia Combinada , Relación Dosis-Respuesta a Droga , Evaluación de Medicamentos , Femenino , Estudios de Seguimiento , Humanos , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Mitoxantrona/administración & dosificación , Recurrencia Local de Neoplasia/tratamiento farmacológico , Estudios Prospectivos , Sarcoma/tratamiento farmacológico , Neoplasias de la Tiroides/cirugía , Tiroidectomía
9.
Wien Klin Wochenschr ; 102(9): 260-4, 1990 Apr 27.
Artículo en Alemán | MEDLINE | ID: mdl-2375114

RESUMEN

In the years 1979-1988, operations were performed on 41 anaplastic carcinomas and 11 sarcomas of the thyroid gland. Out of these cases reoperation was indicated in 18 patients (34.6%): in 11 cases only a palliative tracheotomy could be done (group I), whilst in the remaining 7 patients surgical removal of the recurrent tumour was possible (group II). Analysis of group II patients revealed that the initial surgical intervention had been a macroscopically radical operation. The difference between the survival rates of both groups was highly significant (group I 64 days, group II 412 days mean survival). Despite the fatal prognosis of these highly malignant tumours, we conclude that reoperation for the removal of a recurrent tumour is advisable in those patients in whom the initial operation was a radical excision. Longer survival rates and improved quality of life were achieved. If the initial operation was merely palliative, then only a tracheotomy is the likely procedure in case of recurrence.


Asunto(s)
Carcinoma/cirugía , Recurrencia Local de Neoplasia/cirugía , Sarcoma/cirugía , Neoplasias de la Tiroides/cirugía , Anciano , Anciano de 80 o más Años , Carcinoma/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/mortalidad , Reoperación , Sarcoma/mortalidad , Tasa de Supervivencia , Neoplasias de la Tiroides/mortalidad , Tiroidectomía
10.
Wien Klin Wochenschr ; 102(9): 247-9, 1990 Apr 27.
Artículo en Alemán | MEDLINE | ID: mdl-2375110

RESUMEN

In the period from 1957-1989 43 malignant lymphomas of the thyroid gland were treated in the surgical department of Kaiser Elisabeth hospital. 42 were classified as non-Hodgkin lymphomas and one as a Hodgkin lymphoma. The sex distribution was 32 women (mean age 70) to 11 men (mean age 72). The patients were divided into two groups according to postoperative management. First group (1957-1978): conventional irradiation. N = 24 patients, mean survival time 5 months (0-37 months). Second group (1979-1989): high voltage irradiation and/or chemotherapy. N = 19 patients, mean survival time 39 months (1-128 months). All patients in the first group died, whilst in the second group only 9 have died to date. Moreover, 9 of the 10 patients who are still alive are in full remission. Over the past 10 years we have achieved a clear improvement in survival time; this is a result of extended radicality of the surgical procedures, haematological staging and an improvement in the chemotherapy and irradiation regimens.


Asunto(s)
Enfermedad de Hodgkin/cirugía , Linfoma no Hodgkin/cirugía , Neoplasias de la Tiroides/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Femenino , Enfermedad de Hodgkin/mortalidad , Enfermedad de Hodgkin/patología , Humanos , Linfoma no Hodgkin/mortalidad , Linfoma no Hodgkin/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Estudios Retrospectivos , Tasa de Supervivencia , Neoplasias de la Tiroides/mortalidad , Neoplasias de la Tiroides/patología
11.
Vet Rec ; 140(26): 676-8, 1997 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-9234552

RESUMEN

The development of thrombosis of three tarsal veins in a cow was studied by repeated ultrasonographic and venographic examinations for nine months. The venous diameter, the echogenicity of the thrombi and the sequential venographic findings were evaluated. Initially, the thrombosed parts of the ramus cranialis and caudalis of the vena saphena lateralis and the ramus caudalis of the vena saphena medialis had greatly increased diameters and were not compressible. The thrombi appeared as poorly echogenic masses. Within five months, the diameters of the occluded veins had decreased to almost normal dimensions. The echogenicity of the thrombi diminished at their distal and proximal ends. The length of the thrombi was decreased by up to 6.5 cm. However, the thrombosed veins did not re-open. One year after diagnosis, the cow was culled and the persistence of the venous thromboses was confirmed.


Asunto(s)
Enfermedades de los Bovinos/diagnóstico por imagen , Tarso Animal/irrigación sanguínea , Tromboflebitis/veterinaria , Venas/diagnóstico por imagen , Animales , Bovinos , Enfermedades de los Bovinos/patología , Femenino , Estudios de Seguimiento , Flebografía/veterinaria , Tarso Animal/diagnóstico por imagen , Tromboflebitis/diagnóstico por imagen , Factores de Tiempo , Ultrasonografía , Venas/patología
12.
Health Phys ; 80(1): 71-3, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11204121

RESUMEN

The present note describes new advancements to a valued tool in retrospective biodosimetry that lower the threshold of detection of radiation dose to 29 mGy. The advanced method is based on the electron paramagnetic resonance measurements of stable radiation-induced radicals in tooth enamel. Earlier this method had been used only for reconstruction of high radiation doses obtained accidentally. New opportunity of reconstruction of doses lower than 100 mGy opens a new realm of possibilities for assessing the health effects of ionizing radiation at the natural radiation background level.


Asunto(s)
Radiación de Fondo , Diente Molar/efectos de la radiación , Espectroscopía de Resonancia por Spin del Electrón , Humanos , Diente Molar/química , Radiometría/métodos
13.
Artículo en Alemán | MEDLINE | ID: mdl-9459838

RESUMEN

In 837 birds which died or were euthanatized because of their disease, blood could be taken within 12 hours before death. Blood chemistry results were compared with specific necropsy findings of different organs. The parameters aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), creatinine kinase (CK), glutamate dehydrogenase (GLDH), glucose, total protein, uric acid, urea and creatinine were measured. Possible reasons for the bad comparability of blood chemistry results and organ lesions are discussed. Glucose and creatinine were found not to be useful in a routine panel for avian patients.


Asunto(s)
Enfermedades de las Aves/sangre , Aves/sangre , Análisis Químico de la Sangre/veterinaria , Pruebas Enzimáticas Clínicas/veterinaria , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Análisis Químico de la Sangre/métodos , Glucemia/análisis , Proteínas Sanguíneas/análisis , Pruebas Enzimáticas Clínicas/métodos , Creatina Quinasa/sangre , Creatinina/sangre , Glutamato Deshidrogenasa/sangre , L-Lactato Deshidrogenasa/sangre , Urea/sangre , Ácido Úrico/sangre
14.
Infect Genet Evol ; 21: 244-51, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24270014

RESUMEN

Johne's disease, or paratuberculosis, is a chronic fatal ruminant gastroenteritis caused by Mycobacterium avium subspecies paratuberculosis (MAP) whose foodborne zoonotic potential and association with Crohn's disease are still under debate. The disease is widespread but its epidemiology and epizootiology remains elusive. Wildlife is suspected to play a major role. After a surge in MAP seroprevalence in Austrian cattle, paratuberculosis was declared a notifiable disease in Austria in 2006. At the same time a rise in MAP cases in wild ruminant populations in the Austrian province of Styria was reported. All five autochthonous ruminants were affected. Genetic analysis of isolates, yielded numerous genotypes (>15) and several multiple strain infections (15%) across host species. Identical MIRU-VNTR profiles were identified in different species and sampling locations. On the other hand varying MIRU-VNTR profiles were revealed at the same location and in conspecifics. Our data, taken together with earlier epidemiological studies on MAP and other mycobacteria, raised concerns about the organisms' ecology. Constraints regarding in vitro culture of this highly fastidious organism potentially bias our current understanding of its epidemiology. We suggest that MAP infections could be polyclonal and question the informative value of genotyping a single MAP colony derived from a single specimen for epidemiological analysis of MAP.


Asunto(s)
Mycobacterium avium subsp. paratuberculosis/clasificación , Mycobacterium avium subsp. paratuberculosis/aislamiento & purificación , Paratuberculosis/microbiología , Rumiantes/microbiología , Animales , Austria/epidemiología , Femenino , Variación Genética , Genoma Bacteriano , Genotipo , Repeticiones de Minisatélite , Tipificación Molecular , Mycobacterium avium subsp. paratuberculosis/genética , Paratuberculosis/epidemiología , Filogeografía , Zoonosis/epidemiología , Zoonosis/microbiología
15.
J Comp Pathol ; 146(2-3): 274-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21689827

RESUMEN

Infection with Neospora caninum has been diagnosed in a variety of animal species; however, reports in marsupials are rare. A captive Parma wallaby (Macropus parma) died suddenly and was subjected to necropsy examination. The main finding was necrotizing myocarditis associated with protozoan parasites. The protozoa were identified as N. caninum by use of immunohistochemistry and partial gene sequence analysis. Neospora and Toxoplasma should be considered a possible cause of disease in captive marsupials. Further work is required to determine whether marsupials are an accidental or terminal host of this protozoan in order to better understand the host-parasite relationship.


Asunto(s)
Coccidiosis/veterinaria , Macropodidae/parasitología , Neospora/aislamiento & purificación , Animales , Coccidiosis/parasitología , Coccidiosis/patología , Neospora/genética , Neospora/metabolismo
16.
Biosens Bioelectron ; 26(12): 4702-7, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21683571

RESUMEN

Pathological calcification of the cardiovascular system is one of the major causes of high mortality and morbidity in dialysis patients. The inhibition of ectopic calcification relies (I) on the formation of calciprotein particles (CPPs), nanospherical complexes of calcium phosphate mineral, fetuin-A and other acidic serum proteins, and (II) on the stabilization of calcium phosphate prenucleation clusters by fetuin-A monomers. In supersaturated serum, mineral ion aggregation leads to a change in the electrical impedance. In this work, we present a method based on electrochemical impedance spectroscopy (EIS) to establish an impedance trace of mineral ion clustering in vitro. In the presence of 20 µM of serum protein fetuin-A, a prototypic calcification inhibitor, we measured a change in impedance (Δ(R)) of 195.52 ± 27.78%Ω compared to 430.41 ± 11.36%Ω in inhibitor-free samples. We also identified a CPP-formation dependency on the actual content of ions and protein in the samples under investigation. Two-step ripening of CPP was also observed. The presented method may form the basis of a simple label-free bedside or online test to be used in routine clinical practice for estimating the calcification risk in serum.


Asunto(s)
Calcificación Fisiológica , Fosfatos de Calcio/metabolismo , Espectroscopía Dieléctrica/métodos , Fetuínas/metabolismo , Animales , Proteínas Sanguíneas/metabolismo , Calcinosis/sangre , Calcinosis/metabolismo , Bovinos , Espectroscopía Dieléctrica/instrumentación , Diseño de Equipo , Humanos
19.
Ergonomics ; 51(8): 1125-36, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18608483

RESUMEN

Memorising and processing faces is a short-term memory dependent task of utmost importance in the security domain, in which constant and high performance is a must. Especially in access or passport control-related tasks, the timely identification of performance decrements is essential, margins of error are narrow and inadequate performance may have grave consequences. However, conventional short-term memory tests frequently use abstract settings with little relevance to working situations. They may thus be unable to capture task-specific decrements. The aim of the study was to devise and validate a new test, better reflecting job specifics and employing appropriate stimuli. After 1.5 s (short) or 4.5 s (long) presentation, a set of seven portraits of faces had to be memorised for comparison with two control stimuli. Stimulus appearance followed 2 s (first item) and 8 s (second item) after set presentation. Twenty eight subjects (12 male, 16 female) were tested at seven different times of day, 3 h apart. Recognition rates were above 60% even for the least favourable condition. Recognition was significantly better in the 'long' condition (+10%) and for the first item (+18%). Recognition time showed significant differences (10%) between items. Minor effects of learning were found for response latencies only. Based on occupationally relevant metrics, the test displayed internal and external validity, consistency and suitability for further use in test/retest scenarios. In public security, especially where access to restricted areas is monitored, margins of error are narrow and operator performance must remain high and level. Appropriate schedules for personnel, based on valid test results, are required. However, task-specific data and performance tests, permitting the description of task specific decrements, are not available. Commonly used tests may be unsuitable due to undue abstraction and insufficient reference to real-world conditions. Thus, tests are required that account for task-specific conditions and neurophysiological characteristics.


Asunto(s)
Cara , Memoria a Corto Plazo , Pruebas Psicológicas , Adulto , Femenino , Humanos , Masculino , Reconocimiento Visual de Modelos , Valores de Referencia
20.
Biointerphases ; 2(1): 16-20, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20408632

RESUMEN

The concentration of mineral solutes in mammalian blood is considerably higher than that predicted by their solubility product. The plasma protein fetuin-A inhibits calcium phosphate deposition by forming colloidal calciprotein particles (CPPs). In this article the authors present a detailed small angle neutron scattering study including contrast variation analysis providing detailed quantitative information on the three-dimensional topology of the CPPs and on their morphogenesis. In detail the authors found the following: (i) A two stage growth process showing spontaneously formed primary particles with a size of about 500 A diameter that subsequently transformed to 1000 A sized particles which were stable for at least 24 h. (ii) A particular shielding topology was observed for the second CPP state, namely, that a densely packed fetuin-A monolayer covers a mineral core and thereby prevents further crystal growth. (iii) Transmission electron microscopy analysis of in vitro synthesized second state CPPs revealed striking similarities to material retrieved from a human peritonitis patient. This latter finding underscores the importance of short- and long-term stabilizations of CPPs by fetuin-A to enable clearing of mineral debris in the body.

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