196,102 research outputs found
Immunolocalization of estrogen and progesterone receptors in ewe mammary glands
No full textAbstract
Immunopresence of estrogen receptor α (ERα), β (ERβ) and progesterone receptor (PR) were examined in the ewe mammary gland from prepubertal stage to involution. Immunolocalization of ERα revealed a strong positive staining in nuclei of cells composing terminal ductular units (TDUs) in prepubertal ewes. A mild immunoreactivity was identified in early lactating gland. During late lactation immunoreactive product to ERα was observed in the cytoplasm of glandular epithelial cells in all alveoli. In mammary glands at involution ERα positivity was clearly nuclear, with weak to moderate cytoplasmic staining. Cytoplasmic strong immunostaining for ERβ was detected in cells of TDUs, whereas some stromal cells exhibited nuclear staining. A nuclear ERβ immunostaining was observed at early lactation, instead during late lactation, the positivity for ERβ showed only a moderate cytoplasmic distribution. At involution, ERβ positivity was very moderate and detected just in the cytoplasm of shrunken alveoli. Scattered nuclear staining of PR was observed just in mammary glands at early lactation. These results showed that in the mammary glands of sheep both estrogen receptor isoforms were displayed during lactation cycle and that PR appeared just at early lactation, reflecting their regulatory role in alveolar cells
Brain-derived neurotrophic factor modulates mitochondrial dynamics and thermogenic phenotype on 3T3-L1 adipocytes
No full textObesity is a growing threat. In recent years, the finding of functional brown adipose tissue (BAT) in adult humans implemented the studies of anti-obesity therapies based on triggering energy expenditure. The activation of BAT thermogenesis and the recruitment of brite (brown-in-white) adipocytes in white fat pads are under noradrenergic control. Brain-derived neurotrophic factor (BDNF), if centrally administered, enhances thermogenesis through sympathetic activation, but its direct effect on adipocytes is still unclear. The phenotypic change from fat storing to thermogenic adipocytes is recognized by the presence of multilocular lipid droplets (LDs) and fissed mitochondria that tend to surround LDs, maximizing the efficiency of fatty acid release for thermogenesis. BDNF treatment on differentiated 3T3-L1 adipocytes was compared to negative (CTRL) and positive (norepinephrine, NE) controls. BDNF significantly increased small globular mitochondria percentage (> 150% CTRL), while the area surface and elongation index of branched tubules were respectively 55% and 10% lower than NE. Canonical discriminant analysis of mitochondria morphological data clearly separated differentially treated cells with 85% of the total variance. The expression of brown markers and mitochondrial dynamic genes was significantly affected by BDNF. Investigating the pathways involved in adipocyte BDNF stimulation could clarify its role in thermogenesis and its possible local regulation
Expression profile of caseins, estrogen and prolactin receptors in mammary glands of dairy ewes
No full textExpression of Putative Stem Cell Markers Related to Developmental Stage of Sheep Mammary Glands
No full textIt is thought that the regenerative capacity of the mammary gland following post-lactation involution resides in multipotent stem cells within the luminal tissue. Adult stem cells make up a small percentage of the cells found in mature organ systems, however to define useful markers has long been a challenge. c-Kit (KIT) and its ligand stem cell factor (KITLG), ATP-binding cassette sub-family G member 2 (ABCG2) and Musashi 1 (MSI1) are good candidate to identify progenitor cells in their niche. Using real-time PCR we showed that KIT, KITLG and MSI1 expressions were up regulated before lambing and at involution relatively to prepubertal stage. The in situ hybridization analysis for KIT gene confirmed and localized the expression in luminal epithelial cells. The changes in the expression profile of putative stem cell markers in mammary glands of sheep suggest that they modify with the progression of lactation cycle, being up regulated during differentiation and down regulated during lactation
Distribution of BDNF and TrkB isoforms in growing antler tissues of red deer
No full textAntlers are the cranial appendages of deer that regenerate each year;, this renewal provides a model to explore molecules involved in the mammalian organ regeneration. The cellular distributions of the brain-derived neurotrophic factor (BDNF) and the isoforms of its cognate receptor Trk tyrosine kinase receptor (TrkB) were localized by immunohistochemistry in sections of growing red deer antler. BDNF and TrkB full lenght were widely expressed in the integument, perichondrium, periosteum and bone. The truncated isoform receptor was particularly evidenced in integument and vascular inner dermis, but very light reaction was observed in cartilage and bone both at site of endochondral and intramembranous ossification. These observations were also assessed at transcriptional level by RT-PCR analyses. The highest expression of all genes significantly occurred in
chondroprogenitor cells;, however the full-length TrkB receptor was down regulated in osteocartilaginous compartments, where the truncated isoform resulted up regulated. The truncated isoform is a dominant-negative
receptor that inhibits the full length receptor signalling, even if the truncated isoform has not only this only function. This study establishes the presence of BDNF and its receptor in the different cellular compartments of growing antler. Their transcripts assessed by RT-PCR indicates a local synthesis of these molecules that may contribute to the modulation of antler growth, acting as autocrine and/or paracrine factors, independently by nerve supply. Among the plethora of other molecular signals and growth factors affecting the antler growth, the local production of BDNF and its cognate receptor could be of interest in understanding their role on antler renewal and to delineate the different involvement of the receptor isoforms
Simpson–Golabi–Behmel syndrome human adipocytes reveal a changing phenotype throughout differentiation
No full textThe Simpson–Golabi–Behmel syndrome (SGBS) cell strain is widely considered to be a representative in vitro model of
human subcutaneous white pre-adipocytes. These cells achieve a transient expression of classical brown markers, such as
uncoupling protein 1, peaking at day 14 of differentiation and decreasing thereafter. Adipocyte browning process involves
dynamic changes in lipid droplet (LD) dimension, in mitochondria morphology, and in the expression of brown-specific
marker genes. This study analyzes SGBS transient phenotypic transformation by quantifying the heterogeneity of LDs,
mitochondrial dynamics, and a panel of genes involved in adipocyte differentiation and browning. LDs at 21 days of differentiation
were larger than in the previous stages, without any change in the number per cell. The expression of genes
such as peroxisome peroxisome proliferator-activated receptor γ, leptin, and lipase E significantly raised from 0 to 21 days.
Adiponectin was significantly upregulated at 14 days of differentiation. Brown-specific marker PR domain containing 16
was highly expressed at D0. The variability of mitochondrial shape and interconnectivity reflects differences in the relative
rates of fusion and fission, resulting in a significant shift from a networked shape at D7 to a fragmented and swollen one
at D14 and D21. The transient phenotype experienced by this cellular model should be considered whether used in studies
involving the stimulation of adipocyte browning and could be an interesting human model to further elucidate the browning
process in the absence of any stimulation
Expression of a putative stem cell marker, Musashi 1, in mammary glands of ewes
No full textSeveral recent studies demonstrated that development, function and remodelling of mammary glands involved multipotent cells, but no specific molecular markers for mammary epithelial stem cells were revealed. These studies principally concerned human and mouse mammary tissue, but mammary stem cells could be a valuable tool in agricultural production and bioengineering in farm animals. The Musashi-1 (Msi 1) gene encodes an RNA binding protein, which is likely to be associated with self-renewal of neural, intestinal and mammary progenitor cells and is believed to influence the Notch signalling pathway. In this study Musashi-1 expression was detected using immunohistochemistry and in situ hybridisation analysis on mammary glands of ewes at different developmental stages. The protein expression was observed in the epithelial cells at all stages examined. In situ hybridization analysis showed that Msi 1 mRNA has an expression pattern similar to the encoded protein, with positive staining in both nuclei and cytoplasm of ductal, secretory and stromal cells. Ultrastructural in situ analysis confirmed the nuclear and cytoplasmatic expression of Msi. Quantitative analysis of Msi 1 gene expression showed a strong correlation with that of Ki-67, that is a marker of cell proliferation. This is the first report outlining expression of Msi 1 in ovine mammary glands during a complete cycle of lactation
Comparison of the Effects of Browning-Inducing Capsaicin on Two Murine Adipocyte Models
No full textThe increasing prevalence of obesity and its associated comorbidities has gained attention in developing effective treatments and strategies that promote energy expenditure and the conversion of fat from a white to a brite phenotype. Capsaicin, bioactive component of chili peppers and a transient receptor potential channel vanilloid 1 (TRPV1) agonist, has been known to stimulate the process of thermogenesis. In this study, the effects of capsaicin were assessed on two murine cellular models by quantifying the dynamic of lipid droplets (LDs) and the expression of genes involved in adipocyte browning. Present findings demonstrated that treatment with norepinephrine or capsaicin combined with norepinephrine on 3T3-L1 cells and X9 cells significantly promoted the reduction of LDs area surface and size. The transcription of browning related genes such as uncoupling protein 1 (Ucp1), T-box transcription factor 1 (Tbx1), PR domain containing 16 (Prdm16), peroxisome proliferator-activated receptor g coactivator 1a (Ppargc1a) and cell death- inducing DNA fragmentation factor A-like effector A (Cidea) was up-regulated by chronic capsaicin treatment on differentiated 3T3-L1 cells. Instead, X9 cells were significantly responsive only to the treatment with norepinephrine, used as positive control
An oral, low-dose interferon alpha treatment can modulate the stress of early weaning in pigs.
No full textIF THIS THEN THAT Broken Linear Logic. Rethinking and Representing the Design Process
No full textSince its origins, the discipline of Design has developed in close connection with technological progress, trying to adapt its processes, approaches and methodologies. What we are questioning is how much Design has actually been successful in converging towards a disciplinary model suitable to the most recent technological evolutions such as AI and data-driven approaches, and, first of all, how much the way of thinking of designers has changed in this direction.
Through an evaluation of design approaches, methodologies and processes from an historical point of view, the aim of this paper is to surface the misalignment between contemporary design processes logic and the linearity of its common representations, due to recent technological advancements. In fact, the representation of a process affects the epistemology of the process itself. This contribution presents on-going research based on literature review and mapping of contemporary design processes structures and representations, in order to define some good attempts and practices useful for building more reliable representations of design processes able to deal with challenges in a highly-technologically advanced present
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