Search

We present the exploratory approach of Project FOCS (Free Space Optical communications for Space), which aims at proposing and demonstrating new applications of Visible Light Communications (VLC) for satellites. The first selected application scenario that will be investigated deals with transmission of Gbit/s signals on very small satellites, e.g. CubeSats. The second selected research line will be about low-bit-rate communication between satellites over > 100 m distances.

The Bifocal Metrology relates to an optical metrology system applicable to any spacecraft (S/C) which needs to track or point another S/C or when it is needed to measure the relative position/attitude, or to control the reciprocal position/attitude between two S/C in six degrees of freedom in a short, medium and far range by using only one sensor that covers fine and coarse accuracies. It is based on an innovative optical projective system embedded on one S/C and a target composed by three light sources (following isosceles triangle shape) mounted on the other one

We present the high-level approach of TOWS (Transmission of Optical Wireless Signals for telecom satellites) Project, which will design, realize and demonstrate new implementations of optical wireless systems supporting satellite applications. The TOWS systems should allow for seamless integration into present satellite payloads, reducing the weight and material budget, removing cabled connections. The paper presents an overview of the target results and key issues that will be addressed by the TOWS partners.

This paper describes the study of an interferometric instrument for the high-resolution surveillance of the Earth from geostationary orbit (GEO) performed for the EUCLID CEPA 9 RTP 9.9 “High Resolution Optical Satellite Sensor” project of the WEAO Research Cell. It is an in-depth description of a part of the activities described in. The instrument design, both optical and mechanical, is described; tradeoffs have been done for different restoration methods, based on an image generated using calculated point spread functions (PSF’s) for the complete FOV. Co-phasing concept for the optical interferometer has been defined together with the optical metrology needed. Design and simulation of the overall instrument control system was carried out.

This paper describes the internal metrology breadboard development activities performed in the frame of the EUCLID CEPA 9 RTP 9.9 “High Resolution Optical Satellite Sensor” project of the WEAO Research Cell by AAS-I and INETI. The Michelson Interferometer Testbed demonstrates the possibility of achieving a cophasing condition between two arms of the optical interferometer starting from a large initial white light Optical Path Difference (OPD) unbalance and of maintaining the fringe pattern stabilized in presence of disturbances.

Estrogen controls key cellular functions of responsive cells including the ability to survive, replicate, communicate and adapt to the extracellular milieu. Changes in the expression of 8400 genes were monitored here by cDNA microarray analysis during the first 32 h of human breast cancer (BC) ZR-75·1 cell stimulation with a mitogenic dose of 17 -estradiol, a timing which corresponds to completion of a full mitotic cycle in hormone-stimulated cells. Hierarchical clustering of 344 genes whose expression either increases or decreases significantly in response to estrogen reveals that the gene expression program activated by the hormone in these cells shows 8 main patterns of gene activation/inhibition. This newly identified estrogen-responsive transcriptome represents more than a simple cell cycle response, as only a few affected genes belong to the transcriptional program of the cell division cycle of eukaryotes, or showed a similar expression profile in other mitogen-stimulated human cells. Indeed, based on the functions assigned to the products of the genes they control, estrogen appears to affect several key features of BC cells, including their metabolic status, proliferation, survival, differentiation and resistance to stress and chemotherapy, as well as RNA and protein synthesis, maturation and turn-over rates. Interestingly, the estrogen-responsive transcriptome does not appear randomly interspersed in the genome. In chromosome 17, for example, a site particularly rich in genes activated by the hormone, physical association of co-regulated genes in clusters is evident in several instances, suggesting the likely existence of estrogen-responsive domains in the human genome.

In this paper an innovative space metrology system which objective is to measure the mutual arrangement between two spacecrafts is descripted. It is a simple and robust system that makes possible relative attitude measurements between 2 satellites in formation flying with coarse and fine accuracies. Generally, in formation flying mission it's necessary to have a satellite attitude control whose accuracy depends on their relative distance. The proposed metrology is based on an innovative optical projective system embedded on satellite 1 and a target composed by several light sources mounted on satellite 2. Optical system concurrently projects on a CCD two images of the target and from relative position of the light sources on the CCD image plane it's possible to detect position and attitude of the S2. Basic element of innovation of this versatile metrology concept is the possibility to work on a very large S/Cs range distance (~10 m–15 km) and to determinate the relative attitude and position of two spacecrafts on all six degree of freedom in a very simple and fast way.

The importance of agricultural growth to poverty reduction is well known, but the specific channels through which the poor can take advantage of growth require further research. Beyond Food Production takes on this challenge, investigating four important channels: rural labor markets, farm incomes, food prices, and linkages to other economic sectors.

This study was conducted in order to determine the chemical composition and the possible antinociceptive effects in mice of some species of Phyllanthus in vitro. The methanolic extracts obtained from callus cultures of P. fraternus, P. stipulatus and P. caroliniensis caused significant inhibition in to the late phase of the formalin test, whereas the extract from P. urinaria inhibited both neurogenic and inflammatory phases of the test. Conventional chromatographic methods (TLC, GC) permitted the detection of some steroids or triterpenes, including beta-sitosterol, glochidonol and glochidone, which seem be responsible for the antinociceptive effects of the callus extracts studied.

Cyclin-dependent kinases (cdks) are serine-threonine protein kinases that play a key role in the regulation of the mitotic cycle, in transcription initiation, and in the control of specific metabolic pathways in eukaryotic cells. cdk activity is controlled via phosphode-phosphorylation of the catalytic subunits of these enzymes and their physical association with cyclins and cdk inhibitors. In adult rats, estrogen stimulation results in massive proliferation of endometrial epithelial cells, accompanied by functional and structural modifications in all other tissue components of the uterus. We report here that administration of 17 beta-estradiol (E2) to adult ovariectomized rats induces within the first 25 h significant activation of cdk 4, 5, and 6, but not cdk 2, in the uterus, accompanied by increased expression of D-type (D1-3), A and E cyclin messenger RNAs (mRNAs). Furthermore, expression of the cdk inhibitor p27Kip1, a key regulator of uterine functions, is induced by E2 in this organ. Analysis of RNA extracted from E2-stimulated rat endometria shows early accumulation of D1 and D3, but not D2, cyclin mRNA, preceded by transient accumulation of c-fos mRNA. These results indicate an involvement of cdks and cyclins in estrogen actions in adult rat uterus and suggest that cyclins D1 and D3 are part of the molecular pathway that allows hormonal regulation of G1 progression in endometrial cells.

Resume Des homogenats de glandes mammaires et de tumeurs mammaires de souris C3H ovariectomisees furent centrifugees a 105.000g pendant une heure, et les surnageants furent mis en contact avec du 6, 7 - 3 H- 17 -β oestradiol de haute activite specifique. La chromatographie sur des colonnes de Sephadex G- 100 permit la separation de plusieurs pics absorbant a 280 mμ. Le premier pic, qui contenait des macromolecules provenant de la phase interne, presentait, a un haut degre, la faculte de lier l'oestradiol, d'une maniere non covalente, lorsqu'il etait prepare a partir de la glande mammaire normale. Au contraire, le meme pic, provenant de tumeurs mammaires, ne presentait cette faculte de fixer l'oestradiol que de facon partielle ou quasi nulle. Cette observation, et des faits etablis anterieurement, permettent de presenter une hypothese unitaire de la carcinogenese et de la dependance hormonale des tumeurs mammaires.

1. At the example of the production of liver cancer in rats by feeding with 4-dimethyl-aminoazobenzene the problem is examined, whether the metabolism in the liver gradually turns into the cancer-metabolism or suddenly only then, when the carcinogenic degeneration is complete. 2. During the treatment the respiration of the liver evidently but not significantly decreases and is often higher with carcinomas than with the untreated controls. 3. During the treatment the aerobic and mainly the anaerobic glycolysis increase up to the threefold of the initial value. The strongest increase, however, takes place quickly and is detectable already in the beginning of the treatment. 4. After stop of the treatment the alterations completely disappear within 5 days and that also after the highest total doses 4-DAB. The earlier observed glycolysis can therefore not be considered as cancer metabolism, as more as it is inhibited by n/250 oxalate. 5. The produced hepatomas show the characteristic tumor metabolism described by WARBURG. Now the alterations are irreversible. The change takes place abruptly. 6. The cancer-free parts of the same livers show after stop of the treatment a completely normal metabolism. 7. The described results support the view that the occurrence of the strong glycolysis is not the cause but the consequence of the carcinogenic degeneration.

After injection of a physiological amount of 6,7-3H-17β-estradiol into ovariectomized C3H mice,the nonvolatile radioactivity in the mammary gland consists almost exclusively of “free” 17β-estradiol. The mammary gland is able to concentrate and retain 17β-estradiol against a large concentration gradient with the blood. On a dry weight basis, the amount of hormone retained by the mammary tissue is about 1/3 that of uterus, 2/3 that of vagina, 11 times that of omental adipose tissue, 17 times that of lung and 42 times that of muscle. Estrogenic or antiestrogenic substances but not steroids without estrogenic activity are able to compete with 17β-estradiol for the process of accumulation and retention, an indication that this process is highly specific. In all tissues the pool of hormone specifically retained shows a half-life (turnover ti.ne) of about 7 hr. These findings suggest that the mammary gland is able to bind 17β-estradiol in a highly specific manner, and furthermore that this ability is not a pecul...

E stata studiata la permeabilita delle spore bacteriche al piruvato. Il piruvato penetra nelle spore soltanto a pH basso, quando la molecola del chetoacido ed i gruppi polari della superficie delle spore sono largamente indissociati. Le modificazioni della superficie, che si verificano nel corso della esposizione a pH acido, non hanno alcuna importanza nel fenomeno. Questi risultati sono messi in relazione con il fatto che il piruvato induce germinazione delle spore soltanto a pH basso e contribuiscono all'ipotesi che un agente germinante, per essere attivo, deve penetrare nella spora ed attivare i sistemi enzimatici quiescenti.

It was previously shown that calf uterus cytosol contains a Ca2+-activated receptor transforming factor (RTF) which irreversibly converts the larger molecular states of estrogen receptor (5.3 to 8.6 S, depending on ionic strength) into a smaller, salt-stable form (4.5 S, independent of ionic strength). We now describe a method for rapid and reliable separation of precursor and RTF-transformed receptor forms, which takes advantage of a difference in isoelectric point between the two: the more acidic precursor (isoelectric point, 6.2) is still retained by DEAE-cellulose under conditions (0.12 M KCl, pH 8.3) which produce release from cellulose of the less acidic transformed form (isoelectric point, 6.6 to 6.8). Based on this method of separation, RTF activity can be assayed easily and we could thus progress in the purification and physical and functional characterization of this factor, RTF has been purified about 100-fold. Molecular properties, as assayed by methods suited to partially purified preparations, are as follows: sedimentation coefficient, 6.4 S; Stokes radius, 45 A; molecular weight, 115,000; isoelectric point, 4.9. The Michaelis constant, expressed as moles/liter of estradiol binding sites, is 1.25 X 10(8), at pH 7.5 and 4 degrees, pH 8.5 is optimum for activity. RTF attacks native casein (Km, 1.25 X 10(-5) mol/liter at pH 7.5 and 22 degrees) but not hemoglobin, ovalbumin, or albumin. N-Benzoylarginine methyl ester is a competitive inhibitor of RTF-induced receptor transformation, while L-leucylglycylglycine and N-benzoyltyrosinamide are not. RTF activity is protected by -SH compounds. RTF activity is Ca2+-dependent. Ca2+ starts an activation-inactivation cycle of RTF, with permanent loss of transforming activity which proceeds at a particularly fast rate in the absence of substrate. Mg2+ is inactive, while Sr2+ and Mn2+ may in part substitute for Ca2+. RTF is present in both endometrium and myometrium. RTF is not a lysosomal hydrolase, as shown by its alkaline pH optimum (8.5) and exclusive location in cytosol, nor is it trypsin or a protease of the trypsin group. Also, it is distinct from known proteases of human uterus. The functional significance of this Ca2+-activated protease of cytosol with alkaline pH optimum and high affinity for the larger native form of receptor is still unknown.

The estrogen receptor has been purified to homogeneity from calf uterus cytosol by sequential affinity chromatography by using heparin--Sepharose 4B and 17-hemisuccinyl-17beta-estradiol-ovalbumin--Sepharose 4B. The procedure yields about 1.2 mg of receptor protein from 1 kg of calf uteri, with a recovery of 53%. The receptor protein, as a complex with 17beta-[3H]estradiol, is purified more than 99%. A single band is seen on polyacrylamide gel ectrophoresis under nondenaturing conditions. 17beta-[3H]Estradiol comigrates with the protein band. As computed from the specific activity of radioactive hormone, 64,450 g of purified receptor protein binds 1 mol of 17beta-estradiol. 17beta-[3H]Estradiol bound to the protein is displaced by estrogenic steriods but not by progesterone, testosterone, or cortisone. As judged by chromatography on calibrated Sephadex G-200 columns, the purified receptor is identical with native receptor in crude cytosol: both show a Stokes radius of 6.4 nm. On sucrose gradient in low-salt buffer, the purified receptor sediments at 8 S. On electrophoresis in NaDodSO4 gels, the purified receptor migrates as a single protein band with an apparent molecular weight of 70,000. The sedimentation coefficient measured on sucrose gradients in the presence of chaotropic salts [1 M NaBr or NaSCN (0.1 M)] is 4.2 S. We conclude that the estrogen receptor of cytosol consists of a single subunit weighing about 70,000 daltons and endowed with one estrogen binding site. Under native conditions in cytosol, several subunits associate to form a quaternary structure with a Stokes radius of 6.4 nm.

Sodium thiocyanate up to 0.5 M is compatible with a stable estradiol-t-receptor complex during sucrose gradient centrifugation; however, the maximum permissible concentration in 0.1 M during Sephadex G-100 and G-200 chromatography. When NaSCN 0.1 M is added to low-salt cytosol (approximately 7 mg of protein/ml); (1) age-dependent aggregation of receptor is inhibited; (2) peaks of estrogen-binding activity in sucrose gradients and on Sephadex chromatography are sharp; (3) instead of the usual larger molecular states ("8S") found in low salt, most of estrogen receptor is under the following form: 4.1S; Stokes radius, 36 A; mol wt 61 000; flfo, 1.25; homogeneous at electrofocusing, with isoelectric point at 6.0. When cytosol containing NaSCN 0.1 M is diluted down to 2-3 mg of protein/ml or, only for sucrose gradients, NaSCN concentration is increased to 0.4-0.5 M, the 61000 dalton species decreases, being substituted, without loss of bound estradiol-t, by the following estrogen-binding entity: 28S; Stokes radius, 28 A; mol wt 32 000; flfo, 1.44. In the presence of NaSCN, KCl up to 0.4 M does not affect in a significant manner the molecular properties of the above forms. When NaSCN is dialyzed out, most receptor reverts to a 8-9S state. When cytosol is preincubated with Ca2+ (4 mM) and KCl (0.4 M) before addition of NaSCN, the above picture is modified only in the following aspects: (1) Sephadex chromatography peaks are broader and slightly but reproducibly shifted toward higher elution volumes; (2) the electrofocusing pattern consists of a two-peak heterogeneous band shifted toward higher pH (isoelectric points 6.4 and 6.6); (3) upon dialysis of NaSCN there is little or no reversion to faster sedimenting states. These modifications appear to depend on limited proteolytic attack of receptor by Ca2+ -activated receptor transforming factor (RTF), not on binding of Ca2+ to receptor. Present data suggest that the 4.1S entity is a dimer resulting from side-by-side pairing of 2.8S subunits. Molecular dimension of larger receptor forms purified from cytosol are consistent with the hypothesis that under native conditions in vivo dimers are coupled end-by-end into tetrameric structures with two stronger (between subunits) and two weaker (between dimers) bonding regions, and that tetramers may further self-associate. While NaSCN reversibly releases native dimers and subunits by direct impairment of intersubunit bonds, Ca2+ activated RTF irreversibly and specifically releases slightly modified, about 60000 mol wt dimers, by preferential proteolytic attack of the weaker bonding regions and indirect destruction of involved bonds. In vivo, this effect of RTF may be instrumental in mobilization and nuclear penetration of receptor-estradiol complex. Heteroassociation of receptor with other proteins of cytosol is not excluded by the above hypothesis.

A macromolecular component binding 3H-labelled 17 beta-oestradiol in a specific manner and sedimenting in the 8-10-S region on sucrose gradient has been detected in the mammary gland cytosol of ovariectomized adult virgin mice. The dissociation constant of the macromolecule-oestradiol complex is 4.2 times 10(-10)M at 4 degrees C. The binding sites for 17beta-oestradiol of cytosol are 3.7 times 10(-14) mole/mg of protein. Incubation of cytosol with different enzymes suggests that the oestrogen-binding cytosol component is proteinaceous. The binding activity is destroyed by incubation at high temperatures and by some but not all SH-reagents tested. Competition studies show a specificity for oestrogens relative to other steroid hormones. The conclusion is that mammary gland cytosol of virgin mice contains oestradiol receptor. The receptor content does not increase in a specific manner during pregnancy and lactation but rather proportionally to total mammary gland protein.

Summary Calf uterus estrogen receptors either free of 17β-estradiol, i. e., with binding site(s) unprotected, or interacting with the hormone, i.e., with the binding site protected from a direct effect by the ligand, were incubated under a variety of experimental conditions with I2 or several SH reagents. I2 was found to destroy binding activity of unprotected receptor but not the 17β-estradiol-receptor complex. SH reagents did not interfere with binding activity in either case. The results suggest that a tyrosyl and/or histidyl residue(s) is/are present at or near the binding site and that their iodination is incompatible with a stable attachment of 17β-estradiol to the site.

To understand the physiological significance of proteins binding estrogen in calf uterus researchers in Rome have performed studies aimed at purification and characterization of these cytoplasmic and nuclear proteins. By ammonium sulfate fractionation followed by chromatography on Sephadex G-200 the larger and smaller cytoplasmic estrogen binding proteins (EBPs) were purified as estrogen-free molecules. The larter EBP appears to be composed of 4 of the smaller EBPs which appear to consist of subunits with slightly different electric charges. The behavior of binding by both molecular forms suggests existence of a homotropic effect. When the EBP extracted from the nuclear fraction was partially purified it appeared to be the same as the smaller cytoplasmic EBP in all investigated molecular parameters. Puca leads a discussion appended to the main body among several researchers concerning interrelationships in the estrogen receptor system.(Authors modified)

RECENT research (see refs. 1–3) has shown that 17β-oestradiol is specifically taken up and retained, without detectable chemical transformation, by uterus, vagina, adenohypophysis, mammary gland4 and hypothalamus5. In contrast, other organs rapidly release or transform it. In target tissues most of the hormone is found in the nuclear fraction—up to 80 per cent, depending on the homogenization conditions—and the rest is mostly in the 105,000g supernatant6–10. Toft and Gorsky11,12 found that the hormone in the supernatant is bound in larger part to a macromolecule (9.5S) which, at least in part, consists of protein and has the properties of a specific receptor for oestrogens, that is, it shows a high affinity and specificity for oestrogenic molecules.

As measured with the double labeling method with 3H-thymidine and 14C-thymidine in single intact C3H mice about 6 months old, the duration of DNA synthesis in alveolar cells of the mammary gland varies between 14.8 and 27.6 hr, with 20.1 hr as the average. With the same method, in mice ovariectomized and treated for 3–4 days with 1 μg 17-β-estradiol plus 1 mg progesterone per day, duration of DNA synthesis in the same cells varies between 9.5 and 11.9 hr, with an average of 10.7 hr. These results demonstrate that hormones speed up DNA synthesis in the target cells considerably, as well as greatly decrease variation. Two possible hypotheses for the stimulatory effect of hormones are proposed; the first considering an actual influence on the synthetic pathway with following increase of the reaction rate, and the second considering a possible synchronizing effect on chromosome duplication. The large variation of synthetic time in intact mice is ascribed to the variable ovarian secretion. Cyclic hormonal changes are abolished in animals ovariectomized and treated steadily with hormones, with ensuing low variation of the synthetic time. Very large doses of hormones, 10 μg of 17-β-estradiol plus 10 mg of progesterone per day for 3–4 days, or prolonged treatment, 2–3 weeks, with hormones decrease duration of DNA synthesis only to the same extent that the previously reported, less massive, treatments do. The results suggest that a minimum duration of DNA synthesis exists and was reached under any of the hormonal treatments given in this study. As measured by the “wave of labeled mitoses” method, a definite, significant difference was found between minimum duration of DNA synthesis in alveolar cells and cells from buds of 10-week old mice from one side, both having an 8.8 hr synthetic time, and duct cells from the same glands on the other side, which showed a 12.2 hr synthetic time. It was found that both 17-β-estradiol and progesterone, applied independently or in combination, are capable of inducing the same minimum in the same cell type. These results suggest that the minimum duration of DNA synthesis can be a characteristic of the cell, possibly representing the peculiar sequence and spacing of chromosome replication in the particular cell type. Lastly, the results are considered in the context of control of cell proliferation. It is concluded that in the cells of the mammary gland DNA synthesis is not an unadjustable process of the generative cycle, but varies with the proliferation rate. At least for the cells of the mammary gland the hypothesis of absence of correlation between duration of the DNA synthetic phase and generation time appears to be disproved.

Summary An estrogen-binding protein with high specific affinity for 17β-estradiol as well as other estrogens (estrogen receptor) has been purified about 2,500 fold from calf uterus nuclear fraction by a procedure consisting of the following 5 steps: 1) specific solubilization by salt; 2) Ammonium sulfate fractionation; 3) chromatography on DEAE-cellulose; 4) chromatography on Sephadex G-200; 5) Isoelectric fractionation. Physical characteristics of the protein are as follows: Molecular Weight (gel filtration): 80,000–90,000; Sedimentation Coefficient (sucrose gradient): 4.5 S; Isoelectric Point (electrofocusing): 3 peaks at pH 5.9, 6.1 and 6.3; Affinity for 17β-estradiol: K ass = 1.5–2.5 × 10 9 liters/mole at +4 °C. Chemical and other characteristics are also reported. No evidence of difference between this estrogen binding protein from the nuclear fraction and that from the cytoplasmic fraction was found after purification of both according to the described procedure. The purified 4.5 S molecule thus appears to be the fundamental estrogen binding protein of the cell. In the living cell this basic unit may possibly exist in different states of interaction with itself and other molecules. A previous paper ( 1 ) described the purification by a factor of about 40 of an estrogen binding protein from the nuclear fraction of calf uterus. This nuclear protein binds 17β-estradiol, as well as other estrogens, with a high degree of specificity and an association constant in excess of 10 9 liters/mole at +4 °C ( 2 ). This protein thus has the high specific affinity for 17β-estradiol conceptually required of a receptor molecule ( 3 ). This paper deals with the preparation of about 2,500 fold purified estrogen binding protein from the nuclear fraction of immature calf uteri. The protein was tracked through the purification procedure by labeling with 6,7- 3 H-17β-estradiol. The labeling of the protein was accomplished preliminarily, by incubation in vitro of the tissue with the radiohormone. Some physical properties and other characteristics of the estrogen-binding protein were also investigated and are reported. A preliminary account of this research has been given ( 4 ).

IT was shown1 that strips of immature calf uterus incubated in vitro in the presence of 10−9 M 3H-oestradiol-17β concentrate the hormone 400 per cent or more; about 80 per cent of the radioactivity in the tissue is found associated strongly but non-covalently with the nuclear fraction and consists of intact 17β-oestradiol; treatment of the nuclear fraction with 0.4 M KCl at pH 8.5, as already applied by us to rat2, solubilizes an oestradiol-macromolecule complex which sediments at about 5S; the macromolecule is protein, or at least the moiety binding the hormone is protein. A similar 5S oestrophilic component from calf uterus was obtained by Jungblut et al.3. Recent studies4–6 suggest that the 5S macromolecule originates from the 8–10S macromolecular component which binds 17β-oestradiol and is found in the high speed supernatant of uterus.

WHEN 17β-oestradiol and other oestrogens enter a target cell they are bound by highly specific oestrophilic proteins in a strong but non-covalent manner (Kass≃1.3 × 109–1.5 × 109 M−1 for 17β-oestradiol)1. These oestrogen receptors are found in both nuclear and cytoplasmic fractions of uterus and other target organs to this hormone1–11. We now report (1) that iodination of calf uterus oestrogen receptors in alkaline media at lowered temperature destroys their ability to bind 17β-oestradiol; (2) that this effect cannot be ascribed to oxidation of SH groups; and (3) that iodination is ineffective when the binding site is interacting with the hormone, and is thus protected from a direct effect.

Intestinal dysbiosis and adverse food reactions are involved in the pathogenesis of food responsive enteropathy (FRE) in dogs. Various options for an elimination diet are available, and a vegetable dry food is one alternative. Dietary interventions are thought to alter gut microbial communities in healthy individuals and the resolution of dysbiosis is expected in diseased animals concurrent with remission of clinical signs. Therefore, the aim of this study was to evaluate changes in fecal microbiota in dogs with FRE before and after an elimination dietary trial with a vegetable diet. The same vegetable diet trial was performed in healthy control dogs (HC) to evaluate changes in fecal microbiota before and after the trial, and to compare them to FRE dogs.Dogs with FRE (n = 10) and HC (n = 14) were fed the vegetable diet for 60 days. Fecal samples were collected before and after the dietary trial. Fecal genomic DNA was extracted and used for Illumina sequencing of 16S rRNA genes. Sequence data were analyzed using the QIIME pipeline. The dysbiosis index of the sequence data was calculated using a published mathematical model, and a score >0 was considered as dysbiotic. Statistical significance was set at P < 0.05. Significantly lower alpha diversity was observed in dogs with FRE-baseline compared to HC-baseline and FRE-after trial. Distinct microbial communities were observed in dogs with FREbaseline compared to HC-baseline (ANOSIM P = 0.001) and dogs with FRE-after trial (ANOSIM P = 0.032). Microbial communities were still different in FRE-after trial compared to HC-baseline (ANOSIM P = 0.001). The calculated dysbiosis index was higher in dogs with FRE-baseline compared to HC-baseline (P = 0.022), but no significance difference was observed between FRE-after trial and HC-baseline. The fecal microbiota in HC did not show any significant differences before vs. after the vegetable dietary trial. Results of this study suggest that in FRE dogs, treatment with the vegetable elimination diet led to partial recovery of the fecal microbiota by significantly increasing microbiota richness, which was significantly closer to healthy microbiota after treatment. In contrast, no changes were detected in fecal microbiota of healthy control dogs fed with the same vegetable diet.

Exact aetiology for inflammatory chronic enteropathies in dogs remains unknown. Accumulating evidence suggests a pivotal role for intestinal dysbiosis in disease pathogenesis. Many studies have evaluated the alteration of faecal microbiota in canine chronic gastrointestinal (GI) disease, and less research is focused on mucosal microbiota, especially in the ileum and colon. The objectives of the current study were to evaluate ileal and colonic mucosal microbiota in dogs with steroid responsive enteropathy (SRE) before and after 4 months of treatment, and to compare them to control dogs (CD). A total of 10 dogs diagnosed with SRE were enrolled. Complete GI endoscopy was performed and samples were collected by a cytology brush at diagnosis (SRE-Baseline, n = 10) and after 4 month of treatment (SRE-After, n = 8). Oral laxative and 2–4 water enemas were performed before endoscopy. A total of 6 CD that were euthanized for reasons unrelated to this study, with no GI disease, were included. Samples from CD were obtained during necropsy within 3 hours of death. Mucosal genomic DNA was extracted and used for Illumina sequencing of 16S rRNA genes. Sequence data were analysed using the QIIME pipeline. Statistical significance was set at P < 0.05. Clinical signs improved significantly after 4 month of treatment in SRE, but no improvement was seen on endoscopic or histological evaluation. Significant differences in microbial communities between SRE-baseline and CD were observed in the colon (ANOSIM P = 0.002), but not in the ileum (ANOSIM P = 0.180). In dogs with SRE, both ileal and colonic microbial communities remained similar after 4 month of treatment (ANOSIM P = 0.189 and P = 0.637, respectively), and were different from CD (ANOSIM P = 0.001 and P = 0.004, respectively). Results of this study suggest that the mucosal microbiota in the colon of dogs with SRE is different from that of CD. Although clinical signs improved, colonic mucosal dysbiosis was still present after 4 months of treatment.