380 research outputs found
Hedgehog pathway activity in the LADY prostate tumor model
BACKGROUND: Robust Hedgehog (Hh) signaling has been implicated as a common feature of human prostate cancer and an important stimulus of tumor growth. The role of Hh signaling has been studied in several xenograft tumor models, however, the role of Hh in tumor development in a transgenic prostate cancer model has never been examined. RESULTS: We analyzed expression of Hh pathway components and conserved Hh target genes along with progenitor cell markers and selected markers of epithelial differentiation during tumor development in the LADY transgenic mouse model. Tumor development was associated with a selective increase in Ihh expression. In contrast Shh expression was decreased. Expression of the Hh target Patched (Ptc) was significantly decreased while Gli1 expression was not significantly altered. A survey of other relevant genes revealed significant increases in expression of Notch-1 and Nestin together with decreased expression of HNF3a/FoxA1, NPDC-1 and probasin. CONCLUSION: Our study shows no evidence for a generalized increase in Hh signaling during tumor development in the LADY mouse. It does reveal a selective increase in Ihh expression that is associated with increased expression of progenitor cell markers and decreased expression of terminal differentiation markers. These data suggest that Ihh expression may be a feature of a progenitor cell population that is involved in tumor development
Exotic and Emerging Diseases of Animals: An Internet Course for Veterinary Students
US agricultural and companion animals are very vulnerable to the introduction of exotic and emerging animal diseases (EEAD). These diseases could occur through unintentional introduction (the risk of outbreaks grows as free trade increases), could occur through the deliberate introduction of disease agents (bio-terrorism or agro-terrorism), or could emerge as new diseases. EEAD, for the purpose of this course, are defined as those animal diseases that are reportable in the US. This includes diseases on the Office international des épizooties (OIE) List A, selected diseases on List B that either are not found in the US or are reportable, and selected emerging diseases. Some of the exotic and emerging diseases are considered to be foreign animal diseases because they do not occur in the US. Others are found in the US but are under eradication programs. Some are zoonotic and must be monitored and controlled to protect human health. Many of these diseases are important causes of animal suffering and are economically very important. It is essential that veterinarians be familiar with these diseases and have access to accurate, concise information about their salient characteristics
Molecular cloning and hormonal regulation of a murine epididymal retinoic acid-binding protein messenger ribonucleic acid
A complementary DNA encoding the mouse epididymal secretory protein MEP 10 (mouse epididymal protein 10) was cloned and is now renamed murine epididymal retinoic acid binding protein (mE-RABP). The analysis of the predicted primary amino acid sequence showed that mE-RABP has a 75% identity with rat ESP I (epididymal secretory protein I), another epididymal retinoic acid-binding protein. The homology strongly suggests that mE-RABP is the mouse orthologue of rat ESP I. A computer analysis of the predicted three- dimensional structure confirmed that mE-RABP can accommodate retinoic acid as ligand. In the rat, ESP I messenger RNA (mRNA) is expressed in the efferent ducts and in the entire caput epididymidis. However, in the mouse, the expression of a 950-bp mE-RABP mRNA was detected only in principal cells of the mid/distal caput epididymidis, suggesting that the regulation of region- specific expression is different in rat and mouse. Northern blot analyses showed that mE-RABP gene expression is no longer detected 10 days after castration but progressively rebounds between days 15 and 60. However, mE- RABP protein could not be detected by Western blot 30 days after castration. Androgen replacement, begun 5 days after castration and continued for 4 days restored significant expression of mE-RABP mRNA. Efferent duct ligation for 10 days did not affect gene expression. Taken together, these results indicate that mE-RABP mRNA expression is regulated by androgens but not by testicular factors. The overall similarity in the primary amino acid sequence of mE-RABP with ESP I and other members of the lipocalin superfamily suggests that they are evolutionarily related
FOG-1 and GATA-1 act sequentially to specify definitive megakaryocytic and erythroid progenitors
During haematopoiesis, megakaryocytes and erythrocytes derive from a common precursor called preMegE. This study reports a role for the transcription factor FOG-1 in specification of preMegEs, while GATA-1 is subsequently required for erythroid-lineage commitment
Human Case of Lobomycosis
We describe a 42-year-old woman with histologically confirmed lobomycosis, a cutaneous fungal infection rarely reported outside of Latin America. Our case represents the first published report of imported human lobomycosis in Canada and the fifth in an industrialized country
Sorption of fluorescent polystyrene microplastic particles to edible seaweed Fucus vesiculosus
Metadata Framework to Support Deployment of Digital Health Technologies in Clinical Trials in Parkinson’s Disease
Sensor data from digital health technologies (DHTs) used in clinical trials provides a valuable source of information, because of the possibility to combine datasets from different studies, to combine it with other data types, and to reuse it multiple times for various purposes. To date, there exist no standards for capturing or storing DHT biosensor data applicable across modalities and disease areas, and which can also capture the clinical trial and environment-specific aspects, so-called metadata. In this perspectives paper, we propose a metadata framework that divides the DHT metadata into metadata that is independent of the therapeutic area or clinical trial design (concept of interest and context of use), and metadata that is dependent on these factors. We demonstrate how this framework can be applied to data collected with different types of DHTs deployed in the WATCH-PD clinical study of Parkinson’s disease. This framework provides a means to pre-specify and therefore standardize aspects of the use of DHTs, promoting comparability of DHTs across future studies
Erythropoietin guides multipotent hematopoietic progenitor cells toward an erythroid fate
The erythroid stress cytokine erythropoietin (Epo) supports the development of committed erythroid progenitors, but its ability to act on upstream, multipotent cells remains to be established. We observe that high systemic levels of Epo reprogram the transcriptomes of multi- and bipotent hematopoietic stem/progenitor cells in vivo. This induces erythroid lineage bias at all lineage bifurcations known to exist between hematopoietic stem cells (HSCs) and committed erythroid progenitors, leading to increased erythroid and decreased myeloid HSC output. Epo, therefore, has a lineage instructive role in vivo, through suppression of non-erythroid fate options, demonstrating the ability of a cytokine to systematically bias successive lineage choices in favor of the generation of a specific cell type
Cohort Profile:The Danish National Cohort Study of Effectiveness and Safety of SARS-CoV-2 vaccines (ENFORCE)
GLP−1 Promotes Cortical and Medullary Perfusion in the Human Kidney and Maintains Renal Oxygenation During NaCl Loading
BackgroundGLP‐1 (glucagon‐like peptide‐1) receptor agonists exert beneficial long‐term effects on cardiovascular and renal outcomes. In humans, the natriuretic effect of GLP‐1 depends on GLP‐1 receptor interaction, is accompanied by suppression of angiotensin II, and is independent of changes in renal plasma flow. In rodents, angiotensin II constricts vasa recta and lowers medullary perfusion. The current randomized, controlled, crossover study was designed to test the hypothesis that GLP‐1 increases renal medullary perfusion in healthy humans.Methods and ResultsHealthy male participants (n=10, aged 27±4 years) ingested a fixed sodium intake for 4 days and were examined twice during a 1‐hour infusion of either GLP‐1 (1.5 pmol/kg per minute) or placebo together with infusion of 0.9% NaCl (750 mL/h). Interleaved measurements of renal arterial blood flow, oxygenation (R2*), and perfusion were acquired in the renal cortex and medulla during infusions, using magnetic resonance imaging. GLP‐1 infusion increased medullary perfusion (32±7%, P<0.001) and cortical perfusion (13±4%, P<0.001) compared with placebo. Here, NaCl infusion decreased medullary perfusion (−5±2%, P=0.007), whereas cortical perfusion remained unchanged. R2* values increased by 3±2% (P=0.025) in the medulla and 4±1% (P=0.008) in the cortex during placebo, indicative of decreased oxygenation, but remained unchanged during GLP‐1. Blood flow in the renal artery was not altered significantly by either intervention.ConclusionsGLP‐1 increases predominantly medullary but also cortical perfusion in the healthy human kidney and maintains renal oxygenation during NaCl loading. In perspective, suppression of angiotensin II by GLP‐1 may account for the increase in regional perfusion
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