75 research outputs found
Prevalence of inflammatory bowel disease among coeliac disease patients in a Hungarian coeliac centre
BACKGROUND: Celiac disease, Crohn disease and ulcerative colitis are inflammatory disorders of the gastrointestinal tract with some common genetic, immunological and environmental factors involved in their pathogenesis. Several research shown that patients with celiac disease have increased risk of developing inflammatory bowel disease when compared with that of the general population. The aim of this study is to determine the prevalence of inflammatory bowel disease in our celiac patient cohort over a 15-year-long study period. METHODS: To diagnose celiac disease, serological tests were used, and duodenal biopsy samples were taken to determine the degree of mucosal injury. To set up the diagnosis of inflammatory bowel disease, clinical parameters, imaging techniques, colonoscopy histology were applied. DEXA for measuring bone mineral density was performed on every patient. RESULTS: In our material, 8/245 (3,2 %) coeliac disease patients presented inflammatory bowel disease (four males, mean age 37, range 22-67), 6/8 Crohn's disease, and 2/8 ulcerative colitis. In 7/8 patients the diagnosis of coeliac disease was made first and inflammatory bowel disease was identified during follow-up. The average time period during the set-up of the two diagnosis was 10,7 years. Coeliac disease serology was positive in all cases. The distribution of histology results according to Marsh classification: 1/8 M1, 2/8 M2, 3/8 M3a, 2/8 M3b. The distribution according to the Montreal classification: 4/6 Crohn's disease patients are B1, 2/6 Crohn's disease patients are B2, 2/2 ulcerative colitis patients are S2. Normal bone mineral density was detected in 2/8 case, osteopenia in 4/8 and osteoporosis in 2/8 patients. CONCLUSIONS: Within our cohort of patients with coeliac disease, inflammatory bowel disease was significantly more common (3,2 %) than in the general population
Fecal Microbiota in Premature Infants Prior to Necrotizing Enterocolitis
Intestinal luminal microbiota likely contribute to the etiology of necrotizing enterocolitis (NEC), a common disease in preterm infants. Microbiota development, a cascade of initial colonization events leading to the establishment of a diverse commensal microbiota, can now be studied in preterm infants using powerful molecular tools. Starting with the first stool and continuing until discharge, weekly stool specimens were collected prospectively from infants with gestational ages ≤32 completed weeks or birth weights≤1250 g. High throughput 16S rRNA sequencing was used to compare the diversity of microbiota and the prevalence of specific bacterial signatures in nine NEC infants and in nine matched controls. After removal of short and low quality reads we retained a total of 110,021 sequences. Microbiota composition differed in the matched samples collected 1 week but not <72 hours prior to NEC diagnosis. We detected a bloom (34% increase) of Proteobacteria and a decrease (32%) in Firmicutes in NEC cases between the 1 week and <72 hour samples. No significant change was identified in the controls. At both time points, molecular signatures were identified that were increased in NEC cases. One of the bacterial signatures detected more frequently in NEC cases (p<0.01) matched closest to γ-Proteobacteria. Although this sequence grouped to the well-studied Enterobacteriaceae family, it did not match any sequence in Genbank by more than 97%. Our observations suggest that abnormal patterns of microbiota and potentially a novel pathogen contribute to the etiology of NEC
Mechanisms Underlying Stage-1 TRPL Channel Translocation in Drosophila Photoreceptors
Background: TRP channels function as key mediators of sensory transduction and other cellular signaling pathways. In Drosophila, TRP and TRPL are the light-activated channels in photoreceptors. While TRP is statically localized in the signaling compartment of the cell (the rhabdomere), TRPL localization is regulated by light. TRPL channels translocate out of the rhabdomere in two distinct stages, returning to the rhabdomere with dark-incubation. Translocation of TRPL channels regulates their availability, and thereby the gain of the signal. Little, however, is known about the mechanisms underlying this trafficking of TRPL channels. Methodology/Principal Findings: We first examine the involvement of de novo protein synthesis in TRPL translocation. We feed flies cycloheximide, verify inhibition of protein synthesis, and test for TRPL translocation in photoreceptors. We find that protein synthesis is not involved in either stage of TRPL translocation out of the rhabdomere, but that re-localization to the rhabdomere from stage-1, but not stage-2, depends on protein synthesis. We also characterize an ex vivo eye preparation that is amenable to biochemical and genetic manipulation. We use this preparation to examine mechanisms of stage-1 TRPL translocation. We find that stage-1 translocation is: induced with ATP depletion, unaltered with perturbation of the actin cytoskeleton or inhibition of endocytosis, and slowed with increased membrane sterol content. Conclusions/Significance: Our results indicate that translocation of TRPL out of the rhabdomere is likely due to protei
High-frequency variability in neutron-star low-mass X-ray binaries
Binary systems with a neutron-star primary accreting from a companion star
display variability in the X-ray band on time scales ranging from years to
milliseconds. With frequencies of up to ~1300 Hz, the kilohertz quasi-periodic
oscillations (kHz QPOs) represent the fastest variability observed from any
astronomical object. The sub-millisecond time scale of this variability implies
that the kHz QPOs are produced in the accretion flow very close to the surface
of the neutron star, providing a unique view of the dynamics of matter under
the influence of some of the strongest gravitational fields in the Universe.
This offers the possibility to probe some of the most extreme predictions of
General Relativity, such as dragging of inertial frames and periastron
precession at rates that are sixteen orders of magnitude faster than those
observed in the solar system and, ultimately, the existence of a minimum
distance at which a stable orbit around a compact object is possible. Here we
review the last twenty years of research on kHz QPOs, and we discuss the
prospects for future developments in this field.Comment: 66 pages, 37 figures, 190 references. Review to appear in T. Belloni,
M. Mendez, C. Zhang, editors, "Timing Neutron Stars: Pulsations, Oscillations
and Explosions", ASSL, Springe
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Beyond human: The materiality of personhood
NoArchaeological research has been influenced by feminist thought and critique for
decades. In the early 1990s, new narratives began to be written about the past.
Starting with a search for women and gendered identities in our prehistories, these
have developed into a new way of understanding the relationships between people,
objects and animals, both in the past and in the present. Archaeological research
has been concerned with the relationships between the ‘human’ and the ‘other’ for a
number of decades, whether they involve nonhuman animals, objects we use and
create, or attitudes to the landscape and environment. The nonhuman, in other
words, is central to our work. We hope in this piece to demonstrate the contribution
archaeological insights could make to feminist theorising about the
nonhuman
Chemical conversion of human fibroblasts into functional Schwann cells
Direct conversion of one somatic cell type into another represents a promising approach to obtain patient-specific cells for numerous applications. Here, we describe a method allowing the transdifferentiation of human postnatal fibroblasts into functional Schwann cells via a transient progenitor stage. The conversion process is solely based on chemical treatment and does not require the overexpression of ectopic genes. The resulting induced Schwann cells (iSCs) can be characterized by expression of Schwann cell-specific proteins and neuro-supportive and myelination capacity in vitro. This strategy allows to obtain mature Schwann cells from human fibroblasts under chemically defined conditions without the introduction of ectopic genes
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