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1.
Science ; 383(6685): 898-903, 2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38386759

ABSTRACT

The nearby Supernova 1987A was accompanied by a burst of neutrino emission, which indicates that a compact object (a neutron star or black hole) was formed in the explosion. There has been no direct observation of this compact object. In this work, we observe the supernova remnant with JWST spectroscopy, finding narrow infrared emission lines of argon and sulfur. The line emission is spatially unresolved and blueshifted in velocity relative to the supernova rest frame. We interpret the lines as gas illuminated by a source of ionizing photons located close to the center of the expanding ejecta. Photoionization models show that the line ratios are consistent with ionization by a cooling neutron star or a pulsar wind nebula. The velocity shift could be evidence for a neutron star natal kick.

2.
Virus Res ; 227: 15-22, 2017 01 02.
Article in English | MEDLINE | ID: mdl-27697452

ABSTRACT

The young pigeon disease syndrome (YPDS) affects mainly young pigeons of less than one year of age and leads to crop stasis, vomitus, diarrhea, anorexia and occasionally death. This disease is internationally a major health problem because of its seasonal appearance during competitions such as homing pigeon races or exhibitions of ornamental birds. While the etiology of YPDS is still unclear, adenoviruses are frequently discussed as potential causative agents. Electron microscopy of feces from a YPDS outbreak revealed massive shedding of adenovirus-like particles. Whole genome sequencing of this sample identified a novel adenovirus tentatively named pigeon adenovirus 2 (PiAdV-2). Phylogenetic and comparative genome analysis suggest PiAdV-2 to belong to a new species within the genus Aviadenovirus, for which we propose the name Pigeon aviadenovirus B. The PiAdV-2 genome shares 54.9% nucleotide sequence identity with pigeon adenovirus 1 (PiAdV-1). In a screening of further YPDS-affected flocks two variants of PiAdV-2 (variant A and B) were detected which shared 97.6% nucleotide identity of partial polymerase sequences, but only 79.7% nucleotide identity of partial hexon sequences. The distribution of both PiAdV-2 variants was further investigated in fecal samples collected between 2008 and 2015 from healthy or YPDS-affected racing pigeons of different lofts. Independent of their health status, approximately 20% of young and 13% of adult pigeon flocks harbored PiAdV-2 variants. Birds were free of PiAdV-1 or other aviadenoviruses as determined by PCRs targeting the aviadenovirus polymerase or the PiAdV-1 fiber gene, respectively. In conclusion, there is no indication of a correlation between YPDS outbreaks and the presence of PiAdV-2 or other aviadenoviruses, arguing against an causative role in this disease complex.


Subject(s)
Aviadenovirus/classification , Aviadenovirus/genetics , Columbidae/virology , Animals , Animals, Domestic , Aviadenovirus/ultrastructure , Base Sequence , Bird Diseases/epidemiology , Bird Diseases/virology , Computational Biology/methods , Gene Order , Genes, Viral , Genome, Viral , Genomics/methods , Germany , High-Throughput Nucleotide Sequencing , Phylogeny , Polymerase Chain Reaction
3.
Nuklearmedizin ; 52(3): 71-80, 2013.
Article in English | MEDLINE | ID: mdl-23483137

ABSTRACT

UNLABELLED: T stage was redefined for patients with differentiated thyroid carcinoma (DTC) between the 5th and 7th versions of the UICC tumour classification system. PATIENTS, METHODS: 636 patients (486 women, 150 men; mean age 49.1 ± 15.6 years, mean follow-up 4.6 years) who had been treated with ablative radioiodine therapy after thyroidectomy for papillary (PTC) or follicular thyroid carcinomas (FTC) were retrospectively assessed on occurrence of locoregional recurrent disease, or cervical lymph node or distant metastases. Disease-free survival was calculated from initial T stage, classified according to both versions of the UICC staging system and compared with the prognostic value of primary tumour size. Kaplan-Meier method and two measures of explained variation, (1) R2 based on the (partial) likelihood ratio statistic of the Cox proportional hazards model and (2) a model-free variant of a distance measure proposed by Schemper had the aim to detect the most advantageous classification. RESULTS: Of the 508 patients with PTC, 11 (2.2%) developed a local recurrence, 37 (7.3%) cervical lymph node and 23 (4.5%) distant metastases, 3 (2.3%), 8 (6.3%), and 18 (14.1%) were the numbers for the 128 FTC patients respectively. The two classification systems yielded an equal count of statistically significant differences regarding disease-free survival in patients with PTC while UICC 7th classification appeared slightly advantageous in patients with FTC. Regarding explained variation the UICC 7th classification tended to be superior to the UICC 5th classification, both in PTC and FTC, however statistical significance was not reached. CONCLUSION: The primary tumour size significantly added to the prognosis regarding local cervical and distant metastases.


Subject(s)
Adenocarcinoma, Follicular/mortality , Adenocarcinoma, Follicular/pathology , Adenocarcinoma, Papillary/mortality , Adenocarcinoma, Papillary/pathology , Neoplasm Recurrence, Local/mortality , Thyroid Neoplasms/mortality , Thyroid Neoplasms/pathology , Adenocarcinoma, Follicular/radiotherapy , Adenocarcinoma, Papillary/radiotherapy , Adult , Aged , Diagnosis, Differential , Disease-Free Survival , Female , Germany/epidemiology , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/prevention & control , Neoplasm Staging , Prevalence , Prognosis , Reproducibility of Results , Retrospective Studies , Risk Assessment , Sensitivity and Specificity , Survival Analysis , Survival Rate , Thyroid Neoplasms/radiotherapy , Treatment Outcome , Tumor Burden
4.
Article in German | MEDLINE | ID: mdl-22911260

ABSTRACT

The case report describes the successful surgical treatment of an incarcerated hiatal hernia in a 3.5-year-old cat. The animal was presented due to a bad general condition and massive vomiting. Based on clinical examination and diagnostic imaging, laparotomy was performed, revealing a hiatal herniation of the stomach. After reposition and gastropexy, the cat recovered well. She was unremarkable on clinical and radiological follow-up examinations and remained free of gastrointestinal symptoms according to the owner's statement 6 months postoperatively. This case report shows that the described surgical technique is promising in cats with hiatal hernia.


Subject(s)
Cat Diseases/surgery , Hernia, Hiatal/veterinary , Animals , Cat Diseases/diagnostic imaging , Cats , Female , Gastropexy/veterinary , Hernia, Hiatal/diagnostic imaging , Hernia, Hiatal/surgery , Radiography , Treatment Outcome
5.
Science ; 333(6047): 1258-61, 2011 Sep 02.
Article in English | MEDLINE | ID: mdl-21737700

ABSTRACT

We report far-infrared and submillimeter observations of supernova 1987A, the star whose explosion was observed on 23 February 1987 in the Large Magellanic Cloud, a galaxy located 160,000 light years away. The observations reveal the presence of a population of cold dust grains radiating with a temperature of about 17 to 23 kelvin at a rate of about 220 times the luminosity of the Sun. The intensity and spectral energy distribution of the emission suggest a dust mass of about 0.4 to 0.7 times the mass of the Sun. The radiation must originate from the supernova ejecta and requires the efficient precipitation of all refractory material into dust. Our observations imply that supernovae can produce the large dust masses detected in young galaxies at very high redshifts.

6.
Mol Ecol ; 11(5): 891-9, 2002 May.
Article in English | MEDLINE | ID: mdl-11975705

ABSTRACT

Microsatellite and mitochondrial DNA (mtDNA) variability data were used to study outbreaks of Mediterranean fruit fly in California in the years 1992-94 and 1997-99. A total of 359 flies caught in monitoring traps during these years were examined at three polymorphic mtDNA restriction sites and two microsatellite loci. Composite genotypes obtained through analysis of these markers indicate at least five independent introductions of medflies into California between 1992 and 1998. Whereas the majority of specimens displayed a single mtDNA haplotype (AAA), variation of microsatellite alleles among these flies suggests at least one additional introduction in 1993 into southern California. Flies displaying the AAB haplotype sampled in 1992 both in northern and southern California shared microsatellite alleles absent in AAA flies although lacking others commonly found in AAA specimens, thus supporting the hypothesis of an independent introduction of these flies from a different source. In contrast to earlier infestations, a few specimens caught in southern California in 1993 and again in 1998 showed both mtDNA and microsatellite patterns consistent with a Hawaiian origin. Single flies collected in Santa Clara County in 1997 and in El Monte, Los Angeles County & in 1999 most likely represent a sixth and seventh distinct introduction, respectively.


Subject(s)
DNA, Mitochondrial/genetics , Diptera/genetics , Microsatellite Repeats/genetics , Animals , California , DNA/chemistry , DNA/genetics , Gene Library , Genetic Variation , Haplotypes , Nucleic Acid Hybridization , Polymerase Chain Reaction , Population Dynamics
7.
Phys Rev Lett ; 87(23): 236101, 2001 Dec 03.
Article in English | MEDLINE | ID: mdl-11736460

ABSTRACT

By means of kinetic Monte Carlo simulations of the self-organized growth of quantum dots in strained semiconductor systems we resolve the seemingly contradictory features of kinetic versus thermodynamic behavior, e.g., with respect to the temperature dependence of the average dot size and their dispersion. We show that the size distribution immediately after deposition is kinetically controlled, with smaller islands for lower temperatures and larger islands for higher temperatures. For longer simulation times the kinetics leads to equilibration, and a crossover effect between the size distributions occurs, which is in good agreement with the predictions of thermodynamics.

8.
Br J Dermatol ; 145(6): 938-43, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11899147

ABSTRACT

BACKGROUND: After exposure, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is excreted via the faeces, breast milk and epidermal lipids. OBJECTIVES: To determine to what extent TCDD is eliminated via the skin and to evaluate whethe cutaneous elimination can be accelerated by the application of petrolatum. METHODS: In two patients severely intoxicated with TCDD, material obtained from the skin surface and, in one patient, cerumen and the content of epithelial cysts, was analysed for TCDD. RESULTS: The TCDD concentration in the initial blood sample taken was 144 000 pg g(-1) blood fa in patient 1, and 26 000 pg g(-1) blood fat in patient 2. Six months later, when the skin tests were performed, the blood TCDD levels had decreased to 80 900 and 16 100 pg g(-1) blood fat, respectively. In the two samples of pooled cyst contents from patient 1, TCDD levels of 34 400 an 18 600 pg g(-1) fat were found. A cerumen sample contained TCDD at 20 500 pg g(-1) fat. In the material collected from the skin surface we observed a linear increase of the amount of TCD measured per test field with time, indicating a continuous elimination of TCDD via the skin. Th daily amount of TCDD eliminated via the skin was 1.51 pg cm(-2) in patient 1 and 0.57 pg cm(-2) in patient 2. Application of petrolatum led to a twofold increase in the amount of TCDD measured in patient 1, but had no significant effect in patient 2. CONCLUSIONS: In our patients, elimination of TCDD via the skin, most probably through desquamating scales, represented 1-2% of the overall daily TCDD elimination rate, with regard to the body surface and when calculated on the basis of the half-life of TCDD at the time of the skin test. If a more typical overall elimination half-life of 7 years is used as the basis for the calculatio the skin would account for 9% (patient 1) and 15% (patient 2) of the overall elimination. Although we observed an increase in TCDD in material derived from the skin surface of up to 100% after application of petrolatum in patient 1, such an approach appears not to be a feasible means to increase elimination. Owing to the small amount of TCDD measured in skin-surface material, as well as in the cyst contents and cerumen obtained from one patient, contamination of the environment and other persons appears highly unlikely.


Subject(s)
Acne Vulgaris/chemically induced , Environmental Pollutants/pharmacokinetics , Polychlorinated Dibenzodioxins/pharmacokinetics , Skin/metabolism , Teratogens/pharmacokinetics , Acne Vulgaris/metabolism , Adult , Cerumen/metabolism , Emollients/pharmacology , Environmental Pollutants/blood , Environmental Pollutants/poisoning , Female , Follow-Up Studies , Humans , Inactivation, Metabolic , Petrolatum/pharmacology , Polychlorinated Dibenzodioxins/blood , Polychlorinated Dibenzodioxins/poisoning , Skin/drug effects
9.
Article in English | MEDLINE | ID: mdl-11046416

ABSTRACT

By computing the Karhunen-Loeve decomposition (KLD) correlation length xi(KLD) of a reaction-diffusion system in the extensive chaos regime, we show that it is a sensitive measure of spatial dynamical inhomogeneities. It reveals substantial spatial nonuniformity of the dynamics at the boundaries and can also detect slow spatial variations in system parameters. The intensive length xi(KLD) can be easily computed from small local subsystems and is found to have a similar parametric dependence as the two-point correlation length computed over the full system size.

10.
Plant Cell Rep ; 19(3): 235-240, 2000 Jan.
Article in English | MEDLINE | ID: mdl-30754901

ABSTRACT

Embryo axes of four accessions of chickpea (Cicer arietinum L.) were treated with Agrobacterium tumefaciens strains C58C1/GV2260 carrying the plasmid p35SGUSINT and EHA101 harbouring the plasmid pIBGUS. In both vectors the GUS gene is interrupted by an intron. After inoculation shoot formation was promoted on MS medium containing 0.5 mg/l BAP under a selection pressure of 100 mg/l kanamycin or 10 mg/l phosphinothricin, depending on the construct used for transformation. Expression of the chimeric GUS gene was confirmed by histochemical localization of GUS activity in regenerated shoots. Resistant shoots were grafted onto 5-day-old dark-grown seedlings, and mature plants could be recovered. T-DNA integration was confirmed by Southern analysis by random selection of putative transformants. The analysis of 4 plantlets of the T1 progeny revealed that none of them was GUS-positive, whereas the presence of the nptII gene could be detected by polymerase chain reaction.

11.
Lancet ; 354(9186): 1266-7, 1999 Oct 09.
Article in English | MEDLINE | ID: mdl-10520643

ABSTRACT

Two patients with chloracne had concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) of 144,000 and 26,000 pg/g blood lipids. Olestra, a non-digestible, lipophilic dietary fat substitute accelerated the patients' intestinal excretion of TCDD by eight to ten fold. This is sufficient to reduce the normally observed elimination half life of TCDD from about 7 years to 1-2 years.


Subject(s)
Acne Vulgaris/drug therapy , Dietary Fats/therapeutic use , Environmental Pollutants/adverse effects , Environmental Pollutants/blood , Fatty Acids/therapeutic use , Polychlorinated Dibenzodioxins/adverse effects , Polychlorinated Dibenzodioxins/blood , Sucrose/analogs & derivatives , Acne Vulgaris/blood , Acne Vulgaris/chemically induced , Adult , Body Burden , Dietary Fats/administration & dosage , Dose-Response Relationship, Drug , Environmental Pollutants/pharmacokinetics , Fatty Acids/administration & dosage , Feces/chemistry , Female , Half-Life , Humans , Metabolic Clearance Rate , Polychlorinated Dibenzodioxins/chemistry , Polychlorinated Dibenzodioxins/pharmacokinetics , Sucrose/administration & dosage , Sucrose/therapeutic use
12.
Plant J ; 17(5): 557-61, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10205908

ABSTRACT

The recent identification of phage-type RNA polymerases encoded in the nuclear genome of higher plants has provided circumstantial evidence for functioning of these polymerases in the transcription of the mitochondrial and plastid genomes, as demonstrated by sequence analysis and in vitro import experiments. To determine the subcellular localization of the phage-type organellar RNA polymerases in plants, the putative transit peptides of the RNA polymerases RpoT;1 and RpoT;3 from Arabidopsis thaliana and RpoT from Chenopodium album were fused to the coding sequence of a green fluorescent protein (GFP). The constructs were used to stably transform A. thaliana. Transgenic plants were examined for green fluorescence with epifluorescence and confocal laser scanning microscopy. Plants expressing the GFP fusions under control of the CaMV35S promoter exhibited a distinct subcellular localization of the GFP fluorescence for each of the fusion constructs. In plants expressing GFP fusions with the putative transit peptides of ARAth;RpoT;1 and CHEal;RpoT, fluorescence was found exclusively in mitochondria, both in root and leaf cells. In contrast, GFP fluorescence in plants expressing the ARAth;RpoT;3-GFP construct accumulated in chloroplasts of leaf cells and nongreen plastids (leucoplasts) of root cells. By demonstrating targeting in plants, the data add substantial evidence for the phage-type RNA polymerases from C. album and A. thaliana to function in the transcriptional machinery of mitochondria and plastids.


Subject(s)
Arabidopsis/enzymology , DNA-Directed RNA Polymerases/genetics , Genetic Markers , Luminescent Proteins/genetics , Organelles/enzymology , Arabidopsis/genetics , DNA-Directed RNA Polymerases/metabolism , Green Fluorescent Proteins
13.
Int Immunol ; 10(12): 1853-61, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9885906

ABSTRACT

The concept of subdividing CD4+ T cells into Th0, Th1 and Th2 cells is based on the cytokine pattern produced by long-term in vitro cultured T cell lines. However, there exists uncertainty whether this classification can also be applied to CD4+ T cells in vivo. Herein it was investigated whether and at which frequency Th0, Th1 and Th2 cells are induced in vivo during an infection of mice with Leishmania major. Cytokine co-production in single IFN-gamma+ or IL-4+ CD4+ T cells as well as the frequency of such cells were assessed in the lymph nodes (LN) of infected mice. For this purpose, T cells derived from the draining LN were activated by phorbol myristate acetate (PMA)/ionomycin, and the intracellular cytokines IL-2, IL-4, IL-5, IL-10 and IFN-gamma were analyzed by immunofluorescence. One week after infection, a strong, but comparable increase of IFN-gamma+ CD4+ and IL-4+ CD4+ cells (up to 7% of all CD4+ cells) in the LN was observed in resistant C57BL/6 mice and susceptible BALB/c mice. IFN-gamma and IL-4 were not co-produced by single cells ('Th0 cells'). At later stages of the infection, the number of IL-4+ CD4+ cells decreased in C57BL/6, but not in BALB/c mice. All IL-4+ CD4+ cells showed an unexpected phenotype, because at least half of these cells co-produced IL-2, and the majority of the IL-4+ CD4+ did not co-produce the Th2 cytokines IL-5 and IL-10. Similar cytokine profiles were obtained when the CD4+ T cells were stimulated by Leishmania major-antigen instead of PMA/ionomycin. This study demonstrates that 'classical' Th1 cells (IFN-gamma+IL-2+), but no 'classical' Th2 cells (IL-4+IL-5+IL-10+) and no Th0 cells (IFN-gamma+IL-4+) are generated during L. major infection of mice in vivo.


Subject(s)
CD4-Positive T-Lymphocytes/metabolism , Cytokines/biosynthesis , Leishmaniasis, Cutaneous/immunology , Lymph Nodes/metabolism , Animals , Antigens, Protozoan/pharmacology , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/immunology , Cell Line , Female , Genetic Predisposition to Disease , Immunity, Innate , Immunologic Memory , Interferon-gamma/biosynthesis , Interleukin-2/biosynthesis , Interleukin-4/biosynthesis , Leishmaniasis, Cutaneous/genetics , Leishmaniasis, Cutaneous/metabolism , Lymph Nodes/cytology , Lymph Nodes/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mitogens/pharmacology
14.
Science ; 262(5130): 86-9, 1993 Oct 01.
Article in English | MEDLINE | ID: mdl-17742963

ABSTRACT

Much of the interstellar gas resides in photodissociation regions whose chemistry and energy balance is controlled by the flux of far-ultraviolet radiation upon them. These photons can ionize and dissociate molecules and heat the gas through the photoelectric effect working on dust grains. These regions have been extensively modeled theoretically, but detailed observational studies are few. Mapping of the prominent Orion Bar photodissociation region at wavelengths corresponding to the carbon-hydrogen stretching mode of polycyclic aromatic hydrocarbons, the 1-0 S(1) line of molecular hydrogen, and the J = 1-0 rotational line of carbon monoxide allows the penetration of the far-ultraviolet radiation into the cloud to be traced. The results strongly support the theoretical models and show conclusively that the incident far-ultraviolet radiation field, not shocks as has sometimes been proposed, is responsible for the emission in the Orion Bar.

15.
Gesundheitswesen ; 55(1 Suppl): 32-6, 1993 Feb.
Article in German | MEDLINE | ID: mdl-8467126

ABSTRACT

In countries with fee for service billing and direct access to specialist care the general practitioner does not know key figures of the population he serves. As the role of general practice in health-service-research, quality assurance activities and the construction of sentinel-networks is becoming more important, valid methods to determine the denominator are needed. Results from five practices suggest that yearly contact groups should be used as a common denominator for general practice in our health care system. For certain groups of patients (e. g. the elderly > 60 yrs.) even quarterly contact groups can give sufficient information to forecast the yearly contact group.


Subject(s)
Population Surveillance , Practice Patterns, Physicians'/statistics & numerical data , Quality Assurance, Health Care/statistics & numerical data , Adolescent , Adult , Aged , Child , Family Practice/statistics & numerical data , Female , Germany , Humans , Male , Middle Aged , Pilot Projects , Referral and Consultation/statistics & numerical data
16.
Plant Cell Rep ; 12(7-8): 390-4, 1993 May.
Article in English | MEDLINE | ID: mdl-24197338

ABSTRACT

We developed a highly efficient transformation protocol for the PEG-mediated direct transfer of plasmid DNA into protoplasts of haploid Datura innoxia. Vectors harbouring a neomycin phosphotransferase II gene or a hygromycin B phosphotransferase gene under the control of different promoters were used in the transformation experiments. Various amounts of plasmid DNA were applied without any carrier DNA to show the direct influence of the plasmid DNA concentration on the transformation efficiency. Approximately 95% of the selected calli were regenerated to plants; 20% of them remained haploid. Total DNA of different transgenic plants was analysed with regard to the integration pattern of the plasmid DNA. Plants carrying only one or two copies of the vector DNA were observed as well as individuals with multi-copy integration (up to ten or more copies).

18.
Theor Appl Genet ; 83(6-7): 691-4, 1992 Apr.
Article in English | MEDLINE | ID: mdl-24202742

ABSTRACT

Oligonucleotides hybridizing to simple repetitive DNA patterns are highly informative as probes for DNA fingerprinting in all investigated animal species, including man. Here we demonstrate the applicability of this technique in higher plants. The oligonucleotide probes (GTG)5 and (GATA)4 were used to investigate the differences in DNA fingerprint patterns of the following angiosperm species: Triticum aestivum, Secale cereale, Hordeum vulgare, Beta vulgaris, Petunia hybrida, Brassica oleracea, and Nicotiana tabacum. Two species, Hordeum vulgare as a monocot and Beta vulgaris as a dicot, were analyzed in more detail. Their genomes differ considerably in both amount and organization of the simple repetitive sequences (GATA)n, (GACA)n, (GTG)n, and (CT)n due to the evolutionary distance of these two species. Furthermore, several lines and cultivars of Beta vulgaris and Hordeum vulgare can clearly be distinguished on the basis of their highly polymorphic patterns of these repetitive sequences.

20.
Plant Cell Rep ; 9(10): 535-8, 1991 Feb.
Article in English | MEDLINE | ID: mdl-24220706

ABSTRACT

Shoot tips and epicotyl-segments of Vicia narbonensis were co-cultivated with Agrobacterium tumefaciens strain C58C1 pGV 3850 HPT, carrying a plasmid coding for hygromycin-phosphotransferase. On callus-induction medium containing 60 mg/l hygromycin for selection, approximately 18% of the explants produced hygromycin-resistant callus. After transfer to regeneration-medium these calluses produced hygromycin-resistant and nopaline-positive somatic embryos which could be regenerated to plantlets. The integration of the T-DNA into the plant genome was confirmed by Southern analysis.

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