22 research outputs found
A conserved role for Snail as a potentiator of active transcription
The transcription factors of the Snail family are key regulators of epithelial-mesenchymal transitions, cell morphogenesis, and tumor metastasis. Since its discovery in Drosophila ~25 years ago, Snail has been extensively studied for its role as a transcriptional repressor. Here we demonstrate that Drosophila Snail can positively modulate transcriptional activation. By combining information on in vivo occupancy with expression profiling of hand-selected, staged snail mutant embryos, we identified 106 genes that are potentially directly regulated by Snail during mesoderm development. In addition to the expected Snail-repressed genes, almost 50% of Snail targets showed an unanticipated activation. The majority of "Snail-activated" genes have enhancer elements cobound by Twist and are expressed in the mesoderm at the stages of Snail occupancy. Snail can potentiate Twist-mediated enhancer activation in vitro and is essential for enhancer activity in vivo. Using a machine learning approach, we show that differentially enriched motifs are sufficient to predict Snail's regulatory response. In silico mutagenesis revealed a likely causative motif, which we demonstrate is essential for enhancer activation. Taken together, these data indicate that Snail can potentiate enhancer activation by collaborating with different activators, providing a new mechanism by which Snail regulates development
Immunogenicity and Safety of La Sota Strain of Newcastle Disease Virus Administered to Newly Hatched Chicks by Nebulization
The objective of four trials performed on specific-pathogen-free and commercial chickens, either of light or heavy hybrids, was to evaluate the new vaccine delivery method to newly hatched chickens using commercial La Sota vaccine. The vaccine was given by means of nebulization using an ultrasonic device producing homologous aerosol of particles ranging 3–5 microns in diameter. Chickens were exposed to the La Sota vaccine for 30, 60 or 300 s in a closed chamber of the device, thus enabling constant particle size during vaccination. No adverse reaction to the given vaccine was recorded, and the immunity, developed no later than 7 days after vaccination, lasted for at least 49 days which was confirmed by challenge infection using Herts 33 strain of Newcastle disease virus. Maternal antibodies did not influence the development of immunity. Regarding the mode of vaccination, the described method is suitable for the control of Newcastle disease in both big poultry enterprises as well as small backyard flocks when newly hatched chickens are supplied from local hatcheries
Incidence of Histologic Pattern and Anatomic Distribution of Colorectal Carcinoma (1989-2001)
Mucinous Colorectal Carcinomas in Biopsies, 1996-2001
Mucinous colorectal carcinomas show some clinicopathological characteristics that are not found in nonmucinous carcinomas. A total of 1451 colorectal carcinomas were analyzed. Carcinomas were divided into two groups according to the presence or absence of mucinous content. Then, three independent pathologists reviewed all slides with carcinomas with mucinous content by microscopic morphometry and divided them into two subgroups: mucinous carcinomas (>50% mucin) and colorectal carcinomas with mucin (<50% mucin). The following parameters were analyzed: share of mucinous colorectal cancer and cancer with mucin, sex and age distribution of all three groups of carcinomas, and localization and Dukes stage of mucinous carcinomas and carcinomas with mucin. Mucinous carcinomas were confirmed to have poorer prognosis, predilection for younger age group, higher incidence in the proximal colon, and no male predomination. Colorectal carcinomas with mucin had some characteristics of both mucinous cancer and nonmucinous cancer, and could be positioned somewhere in between these two different groups.Mucinozni adenokarcinomi debelog crijeva se po nekim svojim kliničko-patološkim obilježjima razlikuju od nemucinoznih adenokarcinoma. Napravljena je revizija svih karcinoma debelog crijeva od 1996. do 2001. godine. Karcinome s mucinoznim sadržajem dodatno su pregledala tri neovisna patologa te su podijeljeni u dvije podskupine: mucinozni karcinomi (više od 50% sluzi) i karcinomi s mucinom (manje od 50% sluzi). Dobiveni rezultati pokazuju povećanje udjela karcinoma s mucinoznim sadržajem u ukupnom broju kolorektalnih karcinoma. Predispozicija obolijevanja od karcinoma s mucinoznim sadržajem podjednaka je za oba spola dok su muškarci češće obolijevali od nemucinoznih karcinoma. Usporedba prosječne dobi pokazala je da su bolesnici s mucinoznim karcinomima prosječno mlađi od onih s nemucinoznim i karcinomima s mucinom. Lokalizacija mucinoznih karcinoma i karcinoma s mucinom je bila podjednaka i primjetan je pomak u desni dio kolona. Usporedba Dukesove klasifikacije mucinoznih karcinoma i onih s mucinom pokazala je da se u trenutku dijagnosticiranja većina mucinoznih karcinoma nalazi u Dukesovu stadiju C, za razliku od karcinoma s mucinom kojih je u času dijagnosticiranja bilo podjednako u Dukesovu stadiju A, AC i C bolesti. Dobiveni rezultati pokazuju da se po nekim svojim obilježjima mucinozni karcinomi razlikuju od nemucinoznih, dok karcinomi s mucinom posjeduju neke osobitosti i jednih i drugih