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Basal metabolic rate and the evolution of the adaptive immune system

Vertebrates have evolved an adaptive immune system in addition to the ancestral innate immune system. It is often assumed that a trade-off between costs and benefits of defence governs the evolution of immunological defence, but the costs and benefits specific to the adaptive immune system are poorly known. We used genetically engineered mice lacking lymphocytes (i.e. mice without adaptive, but wi

Differential Akt activation in the photoreceptors of normal and rd1 mice.

Retinitis pigmentosa is a blinding disease in which unknown mechanisms cause the degeneration of retinal photoreceptors. The retinal degeneration (rd1) mouse is a relevant model for this condition, since it carries a mutation also found in some forms of retinitis pigmentosa. To understand the degenerative process in the rd1 mouse, we must identify the survival and apoptosis-related signaling pathw

Effect of electrical stimulation on the activity of muscle exoproteases during beef ageing

Electrical stimulation was applied to bull carcasses at a low voltage (80 V, 15 Hz, 30 s). The pH decline, tenderness, myofibrillar protein degradation, and exoprotease activities were studied in semimembranosus and longissimus dorsi muscles during the ageing process. Electrical stimulation was found to be beneficial for tenderness in longissimus dorsi muscle as determined by shear force and confi

Genetic and morphological variation in Dunlin Calidris alpina breeding in the Palearctic tundra

The extensive overlap in morphological characters between populations of Dunlin Calidris alpina imposes problems of determining the origin of migrating and wintering birds. The morphology of the birds also varies between the sexes, and the sex of a Dunlin may often be difficult to determine. To clarify if mitochondrial DNA can be used to identify which breeding areas migrating Dunlin come from, we

Generating positrons with femtosecond-laser pulses

Utilizing a femtosecond table-top laser system, we have succeeded in converting via electron acceleration in a plasma channel, low-energy photons into antiparticles, namely positrons. The average intensity of this source of positrons is estimated to be equivalent to 2x10(8) Bq and it exhibits a very favorable scaling for higher laser intensities. The advent of positron production utilizing femtose

Decreases in myocardial glucose and increases in pyruvate but not ischaemia are observed during porcine endotoxaemia.

Myocardial dysfunction occurs commonly in septic shock. It is not known whether this is due to local ischaemia and metabolic disturbances. Our hypothesis was that endotoxaemic myocardial dysfunction may be associated with interstitial ischaemic and metabolic changes, measured using interstitial microdialysis (MD). Methods: Eighteen pigs were randomized to control (n=6) or endotoxin infusion (n=12)

A new understanding of au-assisted growth of III-V semiconductor nanowires

Semiconductor nanowires of III-V materials have generated much interest in recent years. However, the growth mechanisms by which these structures form are not well understood. The so-called vapor-liquid-solid (VLS) mechanism has often been proposed for III-V systems, with a chemically inert, liquid metal particle (typically Au) acting as a physical catalyst. We assert here that An is, in fact, not

More pronounced salt dependence and higher reactivity for platination of the hairpin r(CGCGUUGUUCGCG) compared with d(CGCGTTGTTCGCG)

The DNA interference pathways exhibited by cisplatin and related anticancer active metal complexes have been extensively studied. Much less is known to what extent RNA interaction pathways may operate in parallel, and perhaps contribute to both antineoplastic activity and toxicity. The present study was designed with the aim of comparing the reactivity of two model systems comprising RNA and DNA h

Country of birth, instrumental activities of daily living, self-rated health and mortality: a Swedish population-based survey of people aged 55-74.

There is scant knowledge of the effects of country of birth on the health of individuals in the years prior to and after retirement. The aim of this study was to consider country of birth in relation to health status, instrumental activities of daily living (IADL) and all-cause mortality when adjusted for socioeconomic status (SES). Cross-sectional data were collected between 1986 and 1991 on 8959

Genetic Variation in Brain-Derived Neurotrophic Factor Is Associated with Serotonin Transporter but Not Serotonin-1A Receptor Availability in Men

Background: The serotonergic system, including the serotonin transporter (5-HTT), which is the target of many antidepressants, seems to be influenced by brain-derived neurotrophic factor (BDNF). Methods: Positron emission tomography (PET) was used to address, in 25 and 53 healthy volunteers, respectively, the possible association between six polymorphisms in the gene encoding BDNF and the availabi

Economic evaluation of enzymatic hydrolysis of phenol-pretreated wheat straw

Experimental data from the enzymatic hydrolysis of phenol-pretreated Swedish wheat straw have been used to evaluate the cost fractions of capital and utility, enzyme, and raw material. Two different raw material prices and varying enzyme prices have been used. The evaluation is based on an empirical model for the enzymatic hydrolysis and a computer program where utility and equipment, enzyme, and

Time-dependent radiative transfer in magneto-optical traps

We investigate radiation-imprisonment (RI) phenomena in a system of cold atoms trapped in magneto-optical traps (MOTs) when cooling lasers are switched off for a short period. The problem is formulated within the framework of the Streater-Cooper-Sandle equation that belongs to the Markov class and accounts for photon frequency redistribution in multiple scattering processes. On the basis of a semi

Continuous versus intermittent tamoxifen versus intermittent/alternated tamoxifen and medroxyprogesterone acetate as first line endocrine treatment in advanced breast cancer: An EORTC phase III study (10863)

Background: Continuous ligand depletion of endocrine responsive tumours may enhance resistance to therapy. Intermittent treatment with tamoxifen (T) was considered to mimic (incomplete) ligand depletion and reintroduction. Furthermore it was postulated that alternating tamoxifen with a non-cross resistant endocrine modality could (further) postpone hormone resistance. Patients and methods: Postmen

Two-dimensional conformation-dependent electrophoresis (2D-CDE) to separate DNA fragments containing unmatched bulge from complex DNA samples

DNA fragments containing mispaired and modified bases, bulges, lesions and specific sequences have altered conformation. Methods for separating complex samples of DNA fragments based on conformation but independent of length have many applications, including (i) separation of mismatched or unmatched DNA fragments from those perfectly matched; (ii) simultaneous, diagnostic, mismatch scanning of mul

Long-term repeatability of winter basal metabolic rate and mass in a wild passerine

P>Basal metabolic rate (BMR) is an important trait in the study of energy management of an individual, especially in small wintering passerines from the north which have one of the highest energy turnover rates in vertebrates. Laboratory studies have shown the trait to be repeatable and heritable, despite its plastic nature. However there is currently a lack of empirical data from wild passerine p

EGF-stimulated migration in ovarian cancer cells is associated with decreased internalization, increased surface expression, and increased shedding of the urokinase plasminogen activator receptor.

Objectives. The EGFR is expressed in malignant ovarian tumor tissue, and tissue content of EGFR has been directly associated with poor prognosis in patients with ovarian cancer. The uPA system plays a role in pericellular proteolysis, cell migration, invasion, and is over-expressed in ovarian cancer. This study explored the effects of EGF on uPAR expression in the ovarian cancer cell line OVCAR-3.

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Purpose: Lymph node status is one of the most important prognostic factors in muscle-invasive bladder cancer. The extent of lymphadenectomy performed in conjunction with cystectomy and the question as to whether this is a staging or therapeutic intervention are matters of discussion. The aim of this study was to evaluate the sentinel node (SN) concept and to correlate findings with tumour status i

Improving emergency response capability : an approach for strengthening learning from emergency response evaluations

The objectives of this study are to develop and demonstrate an approach to improve emergency response capability by strengthening individual and organisational learning from the evaluations of specific emergency responses. An approach was developed based on theories of individual and organisational learning. It was applied to evaluations of three instances of emergency response in the city of Malm

Truncated galectin-3 inhibits tumor growth and metastasis in orthotopic nude mouse model of human breast cancer

Purpose: The goal of this research was to evaluate a potential therapeutic agent for breast cancer based on galectin-3 that has been implicated in tumorigenicity and metastasis of breast cancer. The hypothesis was that therapy with NH2-terminally truncated form of galectin-3 (galectin-3C) will be efficacious for reduction in tumor growth and for inhibition of metastases. Experimental Design: Recom