126 research outputs found
Bifidobacteria and lactobacilli in the gut microbiome of children with non-alcoholic fatty liver disease: which strains act as health players?
Introduction: Non-alcoholic fatty liver disease (NAFLD), considered the leading cause of chronic liver disease in children, can often progress from non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH). It is clear that obesity is one of the main risk factors involved in NAFLD pathogenesis, even if specific mechanisms have yet to be elucidated. We investigated the distribution of intestinal bifidobacteria and lactobacilli in the stools of four groups of children: obese, obese with NAFL, obese with NASH, and healthy, age-matched controls (CTRLs). Material and methods: Sixty-one obese, NAFL and NASH children and 54 CTRLs were enrolled in the study. Anthropometric and metabolic parameters were measured for all subjects. All children with suspected NASH underwent liver biopsy. Bifidobacteria and lactobacilli were analysed in childrenâs faecal samples, during a broader, 16S rRNA-based pyrosequencing analysis of the gut microbiome. Results: Three Bifidobacterium spp. (Bifidobacterium longum, Bifidobacterium bifidum, and Bifidobacterium adolescentis) and five Lactobacillus spp. (L. zeae, L. vaginalis, L. brevis, L. ruminis, and L. mucosae) frequently recurred in metagenomic analyses. Lactobacillus spp. increased in NAFL, NASH, or obese children compared to CTRLs. Particularly, L. mucosae was significantly higher in obese (p = 0.02426), NAFLD (p = 0.01313) and NASH (p = 0.01079) than in CTRLs. In contrast, Bifidobacterium spp. were more abundant in CTRLs, suggesting a protective and beneficial role of these microorganisms against the aforementioned diseases. Conclusions: Bifidobacteria seem to have a protective role against the development of NAFLD and obesity, highlighting their possible use in developing novel, targeted and effective probiotics
Morphological and acrosomal changes of canine spermatozoa during epididymal transit
Background: During epididymal transit, functional and structural modifications leading to full maturation enable male gametes to reach, recognize and fertilize the oocytes. In dogs, little is known on the modifications of spermatozoa during the passage in the epididymis. The aim of this study was to describe the motility, morphology and acrosomal patterns of canine spermatozoa retrieved from the epididymis caput, corpus and cauda.Results: After the dilution required for the collection of epididymal content, sperm motility was significantly higher(P<0.0001) in the cauda compared to corpus and caput.Proportions of spermatozoa with normal morphology were significantly higher in corpus (P =0.02) and cauda(P<0.0001) compared to caput. Overall morphological abnormalities of the head and neck/midpiece were similar in the three different epididymal regions. A significantly increased prevalence of tail defects, mainly represented by single bent tails, was observed in the corpus compared to caput (P<0.0001) and cauda (P=0.006).Numbers of immature sperm with cytoplasmic droplets decreased from the proximal to the distal region of the epididymis. Particularly, proximal cytoplasmic droplets were more frequently found in spermatozoa collected from the caput epididymis than in the corpus (P<0.0001) and in the cauda (P<0.0001), whereas the occurrence of distal cytoplasmic droplets was higher in the corpus than in the caput (P=0.0003) and in the cauda (P<0.05).Significantly higher proportions of spermatozoa with intact acrosomes were retrieved from the cauda epididymis than from the caput (P=0.03) and the corpus (P =0.008). This difference was mainly due to a lower proportion of spermatozoa with abnormal acrosomes (mainly swollen acrosomes) rather than with absent acrosomes. Conclusions: Canine spermatozoa undergo several modifications in the epididymis. The acquisition of progressive motility, migration of the cytoplasmic droplet and acrosomal reshaping lead to mature spermatozoa which are then stored in the cauda epididymis. From this site, spermatozoa can be retrieved and used in assisted reproductive techniques as a valuable tool for propagating genetic traits of high value individuals that dies accidentally or undergoes orchiectomy for medical purposes. Further investigations should be also focused on the potential use of spermatozoa recovered from other epididymal regions
Gut Microbiota Dysbiosis as Risk and Premorbid Factors of IBD and IBS Along the Childhood-Adulthood Transition
WA92: a fixed target experiment to trigger on and identify beauty particle decays
We describe the detectors and trigger system used in the CERN WA92 experiment. The experiment was designed to study the production and decay of beauty particles from 350 GeV/ interactions in copper and tungsten targets. Charged particle tracking is performed using the Omega spectrometer. Silicon microstrip detectors are used to provide precise tracking information in the region of the production and the decay of heavy-flavoured particles and to trigger on the resulting high impact parameter tracks. The precision of vertex reconstruction corresponds to of the mean B-decay proper lifetime. Lepton and high transverse momentum hadron signals are also used in the trigger, which accepts 29\% of B-decays and rejects 98\% of non-beauty interactions
Alignment of the Pixel and SCT Modules for the 2004 ATLAS Combined Test Beam
A small set of final prototypes of the ATLAS Inner Detector silicon tracker
(Pixel and SCT) were used to take data during the 2004 Combined Test Beam. Data
were collected from runs with beams of different flavour (electrons, pions,
muons and photons) with a momentum range of 2 to 180 GeV/c. Four independent
methods were used to align the silicon modules. The corrections obtained were
validated using the known momenta of the beam particles and were shown to yield
consistent results among the different alignment approaches. From the residual
distributions, it is concluded that the precision attained in the alignment of
the silicon modules is of the order of 5 micrometers in their most precise
coordinate.Comment: 22 pages, submitted to JINST, 129 author
ATLAS pixel detector electronics and sensors
The silicon pixel tracking system for the ATLAS experiment at the Large Hadron Collider is described and the performance requirements are summarized. Detailed descriptions of the pixel detector electronics and the silicon sensors are given. The design, fabrication, assembly and performance of the pixel detector modules are presented. Data obtained from test beams as well as studies using cosmic rays are also discussed
A sensory and nutritional validation of open ocean mussels (Mytilus galloprovincialis Lmk.) cultured in SE Bay of Biscay (Basque Country) compared to their commercial counterparts from Galician RĂas (Spain)
Assessment of DNA fragmentation of feline epididymal spermatozoa : comparison between Sperm-Halomax® and TUNEL assay
The integrity of the paternal DNA is of crucial importance for the embryo development (1) and a relationship between DNA damage and infertility has been demonstrated in humans. Spermatozoa with severe DNA damage remain functionally intact, with normal fertilizing ability, but a high index of DNA fragmentation (DFI) results in a significant decrease in pregnancy rates (2). Feline species is affected by teratozoospermia, but sperm morphology per se is not a reliable predictor of DNA alterations (3). Among different techniques aimed at analyzing sperm DNA status, terminal deoxynucleotidyl transferase mediated nick end labelling (TUNEL) has been applied to spermatozoa of different species including cats (4). However, this technique is either labour intensive and requires expensive instrumentations. Recently, a kit (Sperm-Halomax\uae) specifically developed for boar (5), bull (6), stallion (7) and dog semen (8), but not for cat semen, became commercially available. This kit is based on the sperm chromatin dispersion (SCD) test. Spermatozoa are immersed in an agarose matrix on a slide and briefly incubated in a lysing solution to remove membranes and proteins. DNA fragmentation produces large halos, whereas those sperm with low levels of fragmentation show small halos and the evaluation can be performed by light microscopy.
The aim of the present study was to verify whether the Sperm-Halomax\uae assay could be used for the evaluation of DNA status of epididymal cat spermatozoa. For this purpose, DNA fragmentation indexes obtained with Sperm-Halomax\uae and TUNEL were compared.
Materials and methods. Epididymal spermatozoa were collected from 10 tomcats subjected to routine orchiectomy. Epididymides and vasa deferentia were dissected and squeezed to collect epididymal fluid in a warmed (37\ub0C) PBS without Calcium and Magnesium. Samples were divided in two aliquots and DNA status was evaluated by Sperm-Halomax\uae for canine spermatozoa (Halotech DNA SL, Madrid, Spain) and TUNEL (Calbiochem\uae FragEL\u2122 DNA fragmentation detection kit, Fluorescent \u2013 TdT Enzyme; EMD Millipore Billerica, MA, USA) according to manufacturer's instructions. Values are presented as mean \ub1 standard deviation (SD). Significant differences (P<0.05) were determined by Student\u2019s t-test.
Results. No differences were observed in DFI obtained with Sperm-Halomax\uae and TUNEL (4.34 \ub1 0.93% vs. 4.26 \ub1 0.83%; P = 0.84). These results show that Sperm-Halomax\uae for canine spermatozoa gives a reliable evaluation of DNA fragmentation of epididymal feline spermatozoa.
Conclusion. Sperm-Halomax\uae assay is rapid and easy to perform compared to TUNEL and the assessment of DFI might be included in the standard semen analysis. It might significantly contribute to the evaluation of semen quality and may be an effective diagnostic and prognostic tool to evaluate male factor infertility. Future investigations should be focused on the setting of DFI threshold limit values for feline semen. For this purpose, the sperm DNA status should be correlated with fertility in terms of embryo quality, implantation, and pregnancy
DNA integrity of fresh and frozen canine epididymal spermatozoa
The aims of this study were to evaluate: (1) the effect of cryopreservation on DNA fragmentation of canine epididymal spermatozoa, and (2) the potential protective effect of melatonin on post-thaw sperm quality (motility, morphology, acrosomal and DNA integrity). Epididymal spermatozoa were collected after orchiectomy of ten dogs. Sperm samples were frozen in the presence or absence of melatonin (1 mM). DNA fragmentation index (percentage of spermatozoa with fragmented DNA) was similar in fresh samples (3.3 \ub1 3.6) and samples frozen with (4.2 \ub1 3.8) or without (3.6 \ub1 3.7) melatonin. Sperm motility was significantly (p < 0.0001) higher in fresh compared to frozen samples. The presence of melatonin in the freezing extender did not affect the sperm motility. Proportions of spermatozoa with normal morphology were similar in fresh and frozen samples, irrespective of the presence of melatonin in the extender. Acrosome integrity was significantly decreased (p < 0.01) by cryopreservation, and melatonin did not exert any beneficial effects. In conclusion, DNA fragmentation of canine epididymal spermatozoa was not affected by the freezing procedure, and the presence of melatonin did not preserve motility and acrosome integrity which were adversely affected by cryopreservation. The evaluation of DNA status of thawed gametes is particularly relevant for epididymal spermatozoa since these spermatozoa are usually stored and used in assisted reproductive techniques
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