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1.
Sci Rep ; 6: 35596, 2016 10 21.
Article in English | MEDLINE | ID: mdl-27767125

ABSTRACT

The 'standard' model of cosmology is founded on the basis that the expansion rate of the universe is accelerating at present - as was inferred originally from the Hubble diagram of Type Ia supernovae. There exists now a much bigger database of supernovae so we can perform rigorous statistical tests to check whether these 'standardisable candles' indeed indicate cosmic acceleration. Taking account of the empirical procedure by which corrections are made to their absolute magnitudes to allow for the varying shape of the light curve and extinction by dust, we find, rather surprisingly, that the data are still quite consistent with a constant rate of expansion.

2.
J Anim Ecol ; 81(2): 403-10, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22039986

ABSTRACT

1. Predators often prey on individuals that are sick or otherwise weakened. Although previous studies have shown higher abundance of parasites in prey, whether prey have elevated loads of micro-organisms remains to be determined. 2. We quantified the abundance of bacteria and fungi on feathers of woodpigeons Columba palumbus L., jays Garrulus glandarius L. and blackbirds Turdus merula L. that either fell prey to goshawks Accipiter gentilis L. or were not depredated. 3. We found an almost three-fold increase in bacterial load of prey compared with non-prey, while there was no significant difference between prey and non-prey in level of fungal infection of the plumage. 4. The results were not confounded by differences in size or mass of feathers, date of collection of feathers, or date of analysis of feathers for micro-organisms. 5. These findings suggest a previously unknown contribution of bacteria to risk of predation, with important implications for behaviour, population ecology and community ecology.


Subject(s)
Bacteria/isolation & purification , Feathers/microbiology , Food Chain , Fungi/isolation & purification , Hawks/physiology , Animals , Bacterial Load , Colony Count, Microbial , Columbidae/microbiology , Denmark , Predatory Behavior , Songbirds/microbiology
3.
J Anim Ecol ; 79(4): 777-84, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20202013

ABSTRACT

1. The duration of the reproductive season may depend on the duration of the growing season, with recent amelioration in spring temperatures allowing earlier start of reproduction. Earlier start of reproduction may allow a longer breeding season because of more broods a longer interval between broods for multi-brooded species. 2. We analysed extensive long-term data sets on timing of breeding in 20 species of birds from Denmark, based on records of over 100 000 individual offspring, showing considerable heterogeneity among species in temporal change in duration of the breeding season. 3. Multi-brooded species increased the duration of their breeding season by 0.43 days year(-1) while single-brooded species decreased the duration of their breeding season by 0.44 days year(-1). This implies that recent climate change has allowed more broods or better temporal spacing of broods in multi-brooded species, while the time window for reproduction has become narrower in single-brooded species. 4. The single-most important predictor of change in duration of the breeding season was change in the date breeding started; there was no change in the date of end of breeding. Species advancing their breeding date the most also expanded the duration of the breeding season. In contrast, long-distance migration and generation time did not predict change in duration of the breeding season.


Subject(s)
Birds , Climate Change , Reproduction , Animals , Denmark , Female , Male , Population Dynamics , Seasons
4.
J Evol Biol ; 22(6): 1234-41, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19344382

ABSTRACT

Prey use their locomotory capacity to escape predators, and there should thus be strong viability selection on locomotory morphology of prey. We compared feather morphology of wood pigeons Columba palumbus killed by goshawks Accipiter gentilis with that of survivors to quantify directional and quadratic selection on primary and rectrix feathers. The goshawk is mainly a predator attacking by surprise, leaving wood pigeons with an ability to accelerate fast at a selective advantage. There was directional selection for light primary feathers with a narrow calamus. In addition, there was directional selection for increased area of rectrices. These patterns of natural selection were confirmed in multivariate analyses of selection that showed selection for light primary feathers with a large area and narrow calamus and for a large area of rectrix feathers. These results provide evidence of selection on different aspects of feather morphology directly related to flight performance and thus escape ability from predators.


Subject(s)
Columbidae/anatomy & histology , Escape Reaction/physiology , Feathers/anatomy & histology , Flight, Animal/physiology , Selection, Genetic , Animals , Columbidae/physiology , Female , Hawks , Male , Predatory Behavior
5.
Clin Exp Immunol ; 138(1): 66-74, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15373907

ABSTRACT

Integrin alpha4beta 7 is the principal gut-homing receptor, and it is assumed that expression of this specific integrin directs lymphocytes to the gut in vivo. Adoptive cellular immunotherapy against inflammatory bowel disease (IBD) may depend on the expression of integrin alpha4beta 7 to accomplish local delivery of intravenously injected regulatory T cells in inflamed gut mucosa. The present study aimed to investigate whether in vitro expanded human T cells from the colonic mucosa maintain integrin expression, show in vitro adhesion and retain in vivo gut-homing properties during cultivation. Whole colonic biopsies from healthy subjects were cultured in the presence of interleukin-2 (IL-2) and IL-4. The integrin expression of the cultured T cells was determined by flow cytometry and in vitro adhesion was assessed in a mucosal addressin cell adhesion molecule 1 (MAdCAM-1) adhesion assay. We studied the homing pattern after autologous infusion of 3 x 10(8 111)Indium ((111)In)-labelled T cells in five healthy subjects using scintigraphic imaging. The cultured CD4(+)CD45RO(+) gut-derived T cells express higher levels of integrin alpha4beta 7 than peripheral blood lymphocytes (PBLs) and show strong adhesion to MAdCAM-1 in vitro, even after (111)In-labelling. Scintigraphic imaging, however, showed no gut-homing in vivo. After prolonged transit through the lungs, the T cells migrated preferentially to the spleen, liver and bone marrow. In conclusion, it is feasible to infuse autologous T cells cultured from the gut mucosa, which may be of interest in adoptive immunotherapy. Despite high expression of the gut-homing integrin alpha4beta 7 and adhesion to MAdCAM-1 in vitro, evaluation by (111)In-scintigraphy demonstrated no gut-homing in healthy individuals.


Subject(s)
Colon/immunology , Immunoglobulins/immunology , Integrins/analysis , Intestinal Mucosa/immunology , Mucoproteins/immunology , T-Lymphocytes/immunology , Adult , Antigens, CD/immunology , Bone Marrow/immunology , Cell Adhesion/immunology , Cell Adhesion Molecules , Cell Movement/immunology , Cells, Cultured , Female , Humans , Indium Radioisotopes , Integrins/immunology , Interleukin-2/immunology , Interleukin-4/immunology , Liver/immunology , Lung/immunology , Male , Middle Aged , Receptors, Lymphocyte Homing/immunology , Spleen/immunology
6.
Int J Syst Bacteriol ; 49 Pt 2: 859-65, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10319511

ABSTRACT

A sulfate-reducing bacterium, designated strain lacT, was isolated from surface-sterilized roots of the benthic macrophyte Zostera marina. Cells were motile by means of a single polar flagellum. Strain lacT utilized lactate, pyruvate, malate, ethanol, L-alanine, fumarate, choline and fructose with sulfate as electron acceptor. In addition, fumarate, pyruvate and fructose were also degraded without an external electron acceptor. Sulfate could be substituted with thiosulfate, sulfite and elemental sulfur. Optimal growth was observed between 32.5 and 34.5 degrees C, at an NaCl concentration of 0.2 M and in a pH range between 6.8 and 7.3. The G + C content of the DNA was 42.7 +/- 0.2 mol%. Desulfoviridin and catalase were present. Strain lacT contained c-type cytochromes. Comparative 16S rRNA gene sequence analysis and the fatty acid pattern grouped this isolate into the genus Desulfovibrio. However, strain lacT differs from all other described Desulfovibrio species on the bases of its 16S rRNA gene sequence, the G + C content, its cellular lipid pattern and the utilization pattern of substrates. These characteristics establish strain lacT (= DSM 11974T) as a novel species of the genus Desulfovibrio, for which the name Desulfovibrio zosterae sp. nov. is proposed.


Subject(s)
Desulfovibrio/classification , Plant Roots/microbiology , Poaceae , Sulfates/metabolism , Base Composition , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Desulfovibrio/genetics , Desulfovibrio/isolation & purification , Desulfovibrio/physiology , Fatty Acids/analysis , Fructose/metabolism , Genes, rRNA , Molecular Sequence Data , Oxidation-Reduction , Phenotype , Phylogeny , Pigments, Biological/analysis , RNA, Ribosomal, 16S/genetics
7.
Clin Nucl Med ; 21(9): 695-9, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8879869

ABSTRACT

This is a retrospective study evaluating the efficacy of SPECT in the location of pheochromocytoma. Thirty patients with a suspected pheochromocytoma underwent I-123 metaiodobenzylguanidine (I-123 MIBG) SPECT 4 and 22 hours after intravenous injection of 370 MBq I-123 MIBG. SPECT was compared with planar scintigraphy, CT scanning, histology, and clinical course. Twenty-two-hour I-123 MIBG SPECT correctly identified 10 patients with adrenal medullary pheochromocytoma and correctly excluded pheochromocytoma in 19 patients. The sensitivity of the 22-hour MIBG SPECT was 1.00 and the specificity was 0.95. The positive predictive value was 0.95 and the negative predictive value was 1.00. In 16 patients, planar scintigraphy was compared with SPECT. SPECT located normal adrenal glands and tumors with greater confidence in three dimensions, but the patients with adrenal medullary pheochromocytoma were all correctly identified by planar scintigraphy. The results of SPECT and CT agreed in 29 of 30 patients (96.7%). I-123 MIBG SPECT for the location of pheochromocytoma has a high sensitivity, specificity, and positive and negative predictive values. I-123 MIBG SPECT or CT scanning alone were equally good for locating adrenal medullary pheochromocytoma but the combination of MIBG SPECT and CT makes it possible to distinguish between functioning and nonfunctioning adenomas. I-123 MIBG SPECT may be used alone or in combination with planar scintigraphy when three-dimensional location of a lesion is wanted.


Subject(s)
Adrenal Gland Neoplasms/diagnostic imaging , Adrenal Medulla/diagnostic imaging , Iodine Radioisotopes , Iodobenzenes , Pheochromocytoma/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , 3-Iodobenzylguanidine , Adolescent , Adrenal Gland Neoplasms/urine , Adult , Aged , Aged, 80 and over , Catecholamines/urine , Child , Humans , Middle Aged , Predictive Value of Tests , Retrospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed , Ultrasonography
8.
Ugeskr Laeger ; 158(3): 274-7, 1996 Jan 15.
Article in Danish | MEDLINE | ID: mdl-8607206

ABSTRACT

Ninety children referred to hospital with urinary tract infections (UTI) were investigated by intravenous urography (IVU), ultrasonography (US) and 99m-Tc dimercaptosuccinic acid scan (DMSA). Fifty-eight children also had a micturition cystourethrography performed. In 36 (40%) of the children at least one result was abnormal. In 29 children IVU was abnormal, 10 had abnormal US and 16 had abnormal DMSA. Six of the 58 children had vesicoureteric reflux in eight kidneys. In 16 children IVU was the only examination with an abnormal result, and in ten of these the findings were considered important for treatment or prognosis. In conclusion, IVU is an important supplement to US and DMSA in investigation programs for children with UTI. IVU should be performed in cases of renal scarring or dilatation and in children with recurrent infections.


Subject(s)
Urinary Tract Infections/diagnostic imaging , Chelating Agents , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Prognosis , Radionuclide Imaging , Retrospective Studies , Succimer , Ultrasonography , Urography/methods
10.
Clin Physiol ; 15(5): 467-81, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8846667

ABSTRACT

The purpose of this study was to investigate the pharmacokinetics and dosimetry of using [111In]-labelled F(ab')2 fragments against prostate acid phosphatase (FC-3001, Orion Corporation Farmos, Finland) for the detection of metastatic prostate cancer. Five patients in all were subjected to intraprostatic injection of 1 mg FC-3001 labelled with 85-100 MBq [111In]. In four of the patients the biodistribution was studied by sequential whole-body counting, gamma-camera scintigraphy of the abdomen in antero-posterior and postero-anterior projections. Blood and urine samples were collected sequentially up to 72 h after injection. Initially, significant amounts of antibody fragments were released from the site of injection. After the first 4 h, 22.0% of injected antibody (2.2-41.3% ID) remained in the prostate and was slowly released with a final half-life of 80.4 h (49.9-141.8 h). Labelled antibody appeared in the blood shortly after injection and was cleared from the blood with a final half-life of 27.7-300.9 h. The liver, the bone marrow and, in two patients, the kidneys accumulated antibody fragments in significant amounts during the period of investigation. An apparent relationship between the initial whole-body clearance and renal uptake is described. The effective dose averaged 0.37 mSv/MBq (range 0.24-0.52 mSv/MBq). The highest equivalent doses were received by the kidneys (0.46-2.81 mGy/MBq) the liver (0.44-1.59 mGy/MBq) and the bone marrow (0.37-0.57 mGy/MBq). Only in two of the patients with known metastases were pathological foci seen. The disappointing imaging results were probably caused by the biphasic release of antibody from the prostate, and indicates that intraprostatic injection of this antibody has no advantage for imaging, as well as being unpleasant for the patient. The biodistribution of the antibody following release from the prostate is similar to but more variable than the biodistribution seen in patients after intravenous injection of labelled antibodies.


Subject(s)
Antibodies, Monoclonal , Indium Radioisotopes , Phosphoric Monoester Hydrolases/immunology , Prostatic Neoplasms/diagnostic imaging , Aged , Humans , Male , Middle Aged , Prostate/immunology , Prostatic Neoplasms/enzymology , Radioimmunoassay , Radioligand Assay , Radionuclide Imaging
11.
Acta Paediatr ; 84(1): 84-9, 1995 Jan.
Article in English | MEDLINE | ID: mdl-7734908

ABSTRACT

Ninety children referred to hospital with urinary tract infection (UTI) were investigated by iv urography (IVU), ultrasonography (US) and 99mTc dimercaptosuccinic acid scan (DMSA). Fifty-eight children also underwent micturating cystourethrography (MCUG). In 36 (40%) of the children, at least one result was abnormal. Abnormal findings were found in 29 children with IVU, in 10 with US and in 16 with DMSA. Six of the 58 children had vesicoureteric reflux (VUR) in 8 kidneys. In 16 children, IVU was the only examination with an abnormal result, and in 10 of these the findings were considered important for treatment or prognosis. IVU is an important supplement to US and DMSA in investigation programs for children with UTI. IVU should be performed in cases of renal scars, dilatations or in children with recurrent infections.


Subject(s)
Urinary Tract Infections/diagnostic imaging , Urography , Adolescent , Chi-Square Distribution , Child , Child, Preschool , Contrast Media/administration & dosage , Female , Humans , Infant , Injections, Intravenous , Iohexol/administration & dosage , Male , Organotechnetium Compounds , Predictive Value of Tests , Radionuclide Imaging , Retrospective Studies , Succimer , Technetium Tc 99m Dimercaptosuccinic Acid , Ultrasonography , Urethra/diagnostic imaging , Urinary Bladder/diagnostic imaging , Urography/methods
12.
Nephrol Dial Transplant ; 7(12): 1178-84, 1992.
Article in English | MEDLINE | ID: mdl-1337156

ABSTRACT

Renography with [99mTc] diethylenetriaminepenta-acetate (DTPA) was performed in 26 patients with renal artery stenosis (RAS), unilateral in 15 and bilateral in 11, and in 16 patients with essential hypertension with a normal renal angiogram. Nine of the patients with unilateral RAS were restudied after a successful percutaneous transluminal renal angioplasty (PTRA), i.e. complete removal of the stenosis and a normalization of the blood pressure without antihypertensive treatment. Single-kidney [99mTc]-DTPA clearance and parenchymal mean transit time (MTT) were determined at each examination. All patients were studied on two different days using the same procedure except that captopril 25 mg was given orally before renography at the second examination. In unilateral RAS captopril reduced single-kidney [99mTc]-DTPA clearance significantly on the affected side (-42.7%, median) but not on the unaffected side (-3.2%). In bilateral RAS single-kidney [99mTc]-DTPA clearance was reduced to the greatest extent on the most affected side (-43.0%) compared with the least affected side (-17.2%). In essential hypertension no significant changes were recorded on any side (-1.5% for both). After PTRA, single-kidney [99mTc]-DTPA clearance was not significantly changed by captopril either on the previously affected side (4.3%) or on the unaffected side. MTT was significantly prolonged after captopril on the affected side in unilateral RAS and on the most affected side in bilateral RAS, whereas no significant changes were found on the unaffected side in unilateral RAS, on the least affected side in bilateral RAS, or on any side in essential hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Hypertension, Renovascular/diagnosis , Adult , Aged , Angioplasty, Balloon , Blood Pressure , Captopril , Diagnosis, Differential , Female , Humans , Hypertension/diagnosis , Hypertension/diagnostic imaging , Hypertension, Renovascular/diagnostic imaging , Hypertension, Renovascular/therapy , Male , Middle Aged , Radionuclide Imaging , Renal Artery Obstruction/diagnosis , Renal Artery Obstruction/diagnostic imaging , Renal Artery Obstruction/therapy , Technetium Tc 99m Pentetate
13.
Eur J Nucl Med ; 19(11): 966-70, 1992.
Article in English | MEDLINE | ID: mdl-1425785

ABSTRACT

Eight patients were examined. Seven had verified rhinorrhoea and six had had one or more episodes of pneumococcal meningitis. In four of the patients a fistula could not be visualized by computed tomography. All eight patients had injections of iodine-123-labelled albumin by lumbar puncture. Tomoscintigraphy (SPET) was performed 3, 6 and 8-9 h after injection. After 6-8 h we were able to demonstrate a fistula in seven of the patients with verified rhinorrhoea and the findings were confirmed by a subsequent operation. In one of the patients we were not able to visualize any leak of cerebrospinal fluid into the nasal cavity. This patient was not operated upon and we were not able to verify the findings in this patient. The operated patients all did well after the operation with no relapse of meningitis. In conclusion, SPECT-cisternography after intralumbar injection of iodine-123-labelled albumin is a valuable diagnostic tool for the detection of small fistulae in patients with rhinorrhea.


Subject(s)
Cerebrospinal Fluid Rhinorrhea/diagnostic imaging , Fistula/diagnostic imaging , Serum Albumin, Radio-Iodinated , Tomography, Emission-Computed, Single-Photon/methods , Adult , Cerebrospinal Fluid Rhinorrhea/etiology , Female , Fistula/complications , Humans , Male , Meningitis, Pneumococcal/etiology , Nasal Cavity/diagnostic imaging , Spinal Puncture , Subarachnoid Space/diagnostic imaging , Time Factors , Tomography, X-Ray Computed
14.
Cancer Chemother Pharmacol ; 30(4): 317-20, 1992.
Article in English | MEDLINE | ID: mdl-1643701

ABSTRACT

The mechanism for renal handling of carboplatin was studied in 17 ovarian cancer patients treated with a combination of carboplatin and cyclophosphamide. Carboplatin and [51Cr]-ethylenediaminetetraacetic acid (EDTA) renal clearances were measured simultaneously during short intervals of from 45 to 120 min. A total of 131 clearance intervals were analyzed during 35 chemotherapy courses. The carboplatin/[51Cr]-EDTA clearance ratio (R) served as an indicator of the net tubular reabsorption (R less than 1) or secretion (R greater than 1). The R value was calculated for each sampling interval. No significant difference was found between interpatient and intertreatment variation. The intertreatment variation as tested against the variation in the short intervals by an F-test was highly significant. We calculated the average R value for each treatment and consequently based our results on a total of 35 observations. The mean R value was 0.77 (t-test for R = 1; P less than 0.001). We conclude that the renal elimination of carboplatin takes place by glomerular filtration followed by tubular reabsorption.


Subject(s)
Carboplatin/pharmacokinetics , Kidney/metabolism , Adult , Aged , Carboplatin/urine , Chromium Radioisotopes , Edetic Acid/pharmacokinetics , Female , Humans , Middle Aged , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/embryology , Time Factors
16.
Immunogenetics ; 30(2): 89-98, 1989.
Article in English | MEDLINE | ID: mdl-2569445

ABSTRACT

A serological survey using alloantisera specific for the H-2 class I antigens in Japanese wild mice. Mus musculus molossinus, revealed a high frequency of the H-2Kf antigen. This antigen has also been found in European wild mice, M. m. domesticus and M. m. musculus. In this survey, the H-2Kf antigen was characterized through the use of ten newly isolated monoclonal antibodies raised against cells of a Japanese wild mouse, and by Southern blot analysis using an H-2K locus-specific probe which hybridizes with the 3' end of the gene. The serologically identified H-2Kf antigens revealed several minor variations in reactivities to the monoclonal antibodies. However, all the antigens examined could be clearly separated into two types with respect to the restriction fragment length polymorphism (RFLP) pattern. The first type, found together with a single, characteristic RFLP pattern, was always associated with the presence of reactivity to one particular monoclonal antibody MS54. The second type, found to represent different RFLP patterns, is associated with the absence of reactivity to MS54. This concordance between the presence of an antigenic determinant and a particular RFLP was observed not only within Mus musculus subspecies but also in a different species: M. spretus, carrying the same antigenic determinant, gave an identical RFLP to that of the other MS54-positive Mus musculus subspecies. The data suggest that the antigenic determinant specific for MS54 is an ancient polymorphic structure which has survived the long period of diversification of Mus species (approximately 2-3 million years) without alteration, and is associated with a stable DNA structure at the 3' end of the H-2K gene.


Subject(s)
Biological Evolution , H-2 Antigens/genetics , Histocompatibility Antigens Class II/genetics , Mice/genetics , Muridae/genetics , Animals , Antibodies, Monoclonal/immunology , Haplotypes , Mice/immunology , Polymorphism, Genetic , Polymorphism, Restriction Fragment Length , Species Specificity
18.
Am J Physiol ; 254(6 Pt 2): F802-12, 1988 Jun.
Article in English | MEDLINE | ID: mdl-3289402

ABSTRACT

The effect of flow rate and perfused load on insulin absorption was studied in isolated proximal rabbit tubules. In one series of experiments tubules were perfused for 30 min with 125I-[A14]insulin at 3.6 ng/ml and at flow rates varying between 2.2 and 43.3 nl/min, thus varying both flow rate and the perfused load. In a second series of experiments the tubules were exposed to increasing loads of insulin at a fixed flow rate of 15 nl/min. In a third series of experiments two groups of tubules were exposed to identical perfused loads at two different flow rates. The results showed that absorption is linearly correlated with the perfused load in the ranges of flow rates and concentrations examined. The perfused load determined the magnitude by which the insulin was reabsorbed, whereas the flow rate determined the efficiency (fractional absorption) by which the protein was reabsorbed. At flow rates less than 5 nl/min the fractional absorption was greater than 65%, and at flow rates greater than 30 nl/min fractional absorption was less than 40%. Thus, there is an inverse relationship between flow rate and fractional absorption. The described effects of changes in flow rate and perfused load are suggested to be caused by concomitant changes in the mean luminal concentration.


Subject(s)
Insulin/pharmacokinetics , Kidney Tubules, Proximal/physiology , Absorption , Animals , Female , In Vitro Techniques , Kidney Tubules, Proximal/ultrastructure , Kinetics , Microscopy, Electron , Perfusion , Rabbits
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