In the adult hypothalamus, the neuronal precursor role is attributed to the radial glia‐like cells that line the third‐ventricle (3V) wall called tanycytes. Under nutritional cues, including ...hypercaloric diets, tanycytes proliferate and differentiate into mature neurons that moderate body weight, suggesting that hypothalamic neurogenesis is an adaptive mechanism in response to metabolic changes. Previous studies have shown that the tanycyte glucosensing mechanism depends on connexin‐43 hemichannels (Cx43 HCs), purine release, and increased intracellular free calcium ion concentration (Ca2+)i mediated by purinergic P2Y receptors. Since, Fibroblast Growth Factor 2 (FGF2) causes similar purinergic events in other cell types, we hypothesize that this pathway can be also activated by FGF2 in tanycytes to promote their proliferation. Here, we used bromodeoxyuridine (BrdU) incorporation to evaluate if FGF2‐induced tanycyte cell division is sensitive to Cx43 HC inhibition in vitro and in vivo. Immunocytochemical analyses showed that cultured tanycytes maintain the expression of in situ markers. After FGF2 exposure, tanycytic Cx43 HCs opened, enabling release of ATP to the extracellular milieu. Moreover, application of external ATP was enough to induce their cell division, which could be suppressed by Cx43 HC or P2Y1‐receptor inhibitors. Similarly, in vivo experiments performed on rats by continuous infusion of FGF2 and a Cx43 HC inhibitor into the 3V, demonstrated that FGF2‐induced β‐tanycyte proliferation is sensitive to Cx43 HC blockade. Thus, FGF2 induced Cx43 HC opening, triggered purinergic signaling, and increased β‐tanycytes proliferation, highlighting some of the molecular mechanisms involved in the cell division response of tanycyte.
This article has an Editorial Highlight see https://doi.org/10.1111/jnc.15218.
Fibroblast growth factor 2 (FGF2) accelerates basal‐tanycyte cell division, which is sensitive to Cx43 hemichannel inhibition in vitro and in vivo. In primary cultures of tanycyte, the mitogen FGF2 acts over FGF1R inducing Cx43 hemichannel opening and ATP release. Extracellular ATP induces tanycytic division through P2Y1 receptors. In vivo infusion of FGF2 with a Cx43 hemichannel inhibitor into the 3V showed less tanycytes in mitosis. These findings contribute to elucidate the molecular mechanisms involved in tanycyte proliferation.
This article has an Editorial Highlight see https://doi.org/10.1111/jnc.15218.
Background: Chronic myelogenous leukemia is a neoplastic proliferation of the granulocytic series. In Mexico, chronic myelogenous leukemia accounts for approximately 10% of all leukemias. ...Tyrosine-kinase inhibitors are considered front-line therapy in high-income countries, whereas allogeneic hematopoietic stem cell transplantation is a recognized therapeutic approach, mainly in low- and middle-income countries. Objective: To analyze the overall survival of persons with chronic myelogenous leukemia who have received tyrosine-kinase inhibitors or allogeneic hematopoietic stem cell transplantation in a medical center, since 1994, and briefly discuss the current indications of these treatments in the tyrosine-kinase inhibitors era. Methods: We retrospectively analyzed all patients with a diagnosis of chronic myelogenous leukemia treated in a medical center between 1994 and 2023; subsets of individuals who received an allogeneic hematopoietic stem cell transplantation or tyrosine-kinase inhibitors therapy as first-line treatment were analyzed. Results: 60 persons with chronic myelogenous leukemia were treated with allogeneic hematopoietic stem cell transplantation or tyrosine-kinase inhibitors: 35 received an allogeneic hematopoietic stem cell transplantation, whereas 25 were given tyrosine-kinase inhibitors. All patients who underwent an allogeneic hematopoietic stem cell transplantation engrafted successfully, and the procedure was completed on an outpatient basis in most cases (29/35). The median survival in allogeneic hematopoietic stem cell transplantation was 78.3 months (CI 95%: 0-205.6) and in persons given tyrosine-kinase inhibitors the median was not reached. Conclusion: Tyrosine-kinase inhibitors were significantly superior to allogeneic hematopoietic stem cell transplantation in prolonging the overall survival of persons with chronic myelogenous leukemia in our single institution experience. (Rev Invest Clin. 2024;76(2):91-6).
Air quality time series consists of complex linear and non-linear patterns and are difficult to forecast. Box–Jenkins Time Series (ARIMA) and multilinear regression (MLR) models have been applied to ...air quality forecasting in urban areas, but they have limited accuracy owing to their inability to predict extreme events. Artificial neural networks (ANN) can recognize non-linear patterns that include extremes. A novel hybrid model combining ARIMA and ANN to improve forecast accuracy for an area with limited air quality and meteorological data was applied to Temuco, Chile, where residential wood burning is a major pollution source during cold winters, using surface meteorological and PM
10 measurements. Experimental results indicated that the hybrid model can be an effective tool to improve the PM
10 forecasting accuracy obtained by either of the models used separately, and compared with a deterministic MLR. The hybrid model was able to capture 100% and 80% of alert and pre-emergency episodes, respectively. This approach demonstrates the potential to be applied to air quality forecasting in other cities and countries.
Tanycytes are hypothalamic radial glial-like cells with an important role in the regulation of neuroendocrine axes and energy homeostasis. These cells have been implicated in glucose, amino acids, ...and fatty acid sensing in the hypothalamus of rodents, where they are strategically positioned. While their cell bodies contact the cerebrospinal fluid, their extensive processes contact neurons of the arcuate and ventromedial nuclei, protagonists in the regulation of food intake. A growing body of evidence has shown that purinergic signaling plays a relevant role in this homeostatic role of tanycytes, likely regulating the release of gliotransmitters that will modify the activity of satiety-controlling hypothalamic neurons. Connexin hemichannels have proven to be particularly relevant in these mechanisms since they are responsible for the release of ATP from tanycytes in response to nutritional signals. On the other hand, either ionotropic or metabotropic ATP receptors are involved in the generation of intracellular Ca
2+
waves in response to hypothalamic nutrients, which can spread between glial cells and towards neighboring neurons. This review will summarize recent evidence that supports a nutrient sensor role for tanycytes, highlighting the participation of purinergic signaling in this process.
Slope failures occur in open-pit mining areas worldwide, producing considerable damage in addition to economic loss. Identifying the triggering factors and detecting unstable slopes and precursory ...displacements —which can be achieved by exploiting remote sensing data— are critical for reducing their impact. Here we present a methodology that combines digital photogrammetry, satellite radar interferometry, and geo-mechanical modeling, to perform remote analyses of slope instabilities in open-pit mining areas. We illustrate this approach through the back analysis of a massive landslide that occurred in an active open-pit mine in southwest Spain in January 2019. Based on pre- and post-event high-resolution digital elevation models derived from digital photogrammetry, we estimate an entire sliding mass volume of around 14 million m
3
. Radar interferometry reveals that during the year preceding the landslide, the line of sight accumulated displacement in the slope reached − 5.7 and 4.6 cm in ascending and descending geometry, respectively, showing two acceleration events clearly correlated with rainfall in descending geometry. By means of 3D and 2D stability analyses we located the slope instability, and remote sensing monitoring led us to identify the likely triggers of failure. Las Cruces event can be attributed to delayed and progressive failure mechanisms triggered by two factors: (i) the loss of historical suction due to a pore-water pressure increase driven by rainfall and (ii) the strain-softening behavior of the sliding material. Finally, we discuss the potential of this methodological approach either to remotely perform post-event analyses of mining-related landslides and evaluate potential triggering factors or to remotely identify critical slopes in mining areas and provide pre-alert warning.
Radial glia-like cells in the hypothalamus and dorsal vagal complex are neural precursors (NPs) located near subventricular organs: median eminence and area postrema, respectively. Their strategic ...position can detect blood-borne nutrients, hormones, and mitogenic signals. Hypothalamic NPs increase their proliferation with a mechanism that involves hemichannel (HC) activity. NPs can originate new neurons in response to a short-term high-fat diet as a compensatory mechanism. The effects of high carbohydrate Western diets on adult neurogenesis are unknown. Although sugars are usually consumed as sucrose, more free fructose is now incorporated into food items. Here, we studied the proliferation of both types of NPs in Sprague Dawley rats exposed to a short-term high sucrose diet (HSD) and a control diet. In tanycyte cultures, we evaluated the effects of glucose and fructose and a mix of both hexoses on HC activity. In rats fed an HSD, we observed an increase in the proliferative state of both precursors. Glucose, either in the presence or absence of fructose, but not fructose alone, induced in vitro HC activity. These results should broaden the understanding of the nutrient monitoring capacity of NPs in reacting to changes in feeding behavior, specifically to high sugar western diets.
The use of antibiotics in animal production are widely used for disease treatment, health protection, and as growth promoters. Common antibiotics used in veterinary medicine are excreted and ...eliminated through the sewage system, contaminating water and soil with negative effects on agricultural activities. This systematic review focuses on the trend of research works on antibiotic residues, evaluating antibiotics used in livestock production and their excretion in animal products and in environmental matrices such as water and soil. Our database was composed of 165 articles, reporting the concentration of antibiotic residues found in the environment, livestock (cow, sheep, pig, horse, chicken, rabbit, goat), aquatic and terrestrial animal tissues, animal products (milk and eggs), wastewater, and soil. The documents were obtained from Asia, Africa, North America, South America, Europe, and Oceania. A descriptive analysis of antibiotic residues found worldwide was analyzed according to each of the variables used such as antibiotic family, name, concentration (% and mg/kg or ppm), and country and continent where the residue was found. The descriptive analysis was carried out using the "describe" function of psych package and pirate plots were drawn. According to our study, the main antibiotics used worldwide in animal production are sulfonamides, tetracyclines, quinolones, penicillin, and cephalosporins. At present, despite the trends of increased regulations on the use of antibiotics worldwide, antibiotics are still utilized in food animal production, and are present in water and soil, then, there is still the misuse of antibiotics in many countries. We need to become aware that antibiotic contamination is a global problem, and we are challenged to reduce and improve their use.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The growth in usage of efficient mobile robots in engineering has motivated the search for new alternatives to improve the control tuning task. In this article, Cartesian space ...proportional-derivative control tuning for omnidirectional mobile robots is established under an offline dynamic optimization approach wherein the minimization of the tracking error and energy consumption are considered simultaneously, providing efficient performance in real tests. A statistical study of the performance of twelve different meta-heuristic algorithms and one gradient technique indicates that using the fittest solution in the meta-heuristic optimization process through generations allows finding more suitable controller parameters. Also, real tests with each of the best control gains obtained using algorithms are realized as a laboratory prototype. Analysis of laboratory tests indicate that, statistically,
of comparisons with the best control gains exhibit different performance functions in spite of having only slightly different control gains.
The objective of this study is to use DNA barcoding to link cystacanths and adults belonging to the acanthocephalans
Corynosoma australe
found in the Southeastern Pacific Ocean off the coast central ...from Peru. We sampled three species of commercial fish (
Paralichthys adspersus
(Steindachner),
Paralabrax humeralis
(Valenciennes), and
Cheilodactylus variegatus
(Valenciennes)) and two South American sea lions,
Otaria byronia
, stranded on the beaches of the city of Huacho and Barranca, Lima province. A total of 509 acanthocephalan larvae were found in the body cavity of 95 fish (prevalence 54.28%, total mean intensity 8.64). A total of 127 adult worms were found in the large intestine from two South American sea lions (P= 100%, MI= 63.5). A total of 203 larvae from
P. humeralis
were isolates (P=65.71%; MI= 8.83; MA=5.8), 235 (P=54.29%; MI= 12.37; MA= 6.71) from
C. variegatus
, and 71 (P=42.86%; MI= 4.73; MA= 2.03) from
P. adspersus
. All adult and larval specimens were morphologically identified as
C. australe
. They were generated cytochrome c oxidase subunit 1 (
cox1
) gene sequences of specimens and were compared with available data from GenBank. Molecular phylogenetic analysis supported our morphological identification, where the Peruvian isolates formed a clade with other isolates of
C. australe
from other countries of the American continent. Of the sequences obtained, two haplotypes were detected and were not identical with previous reports. Based on both DNA barcoding and morphological analyses, our finding represents the first molecular data of
C. australe
from Peru and the report of
Cheilodactylus variegatus
as a new paratenic host on the central coast, extending the knowledge and distribution range of this acanthocephalan in Southeastern Pacific Ocean.
PDF
