31 research outputs found
Spectroscopy Apparatus for the Measurement of The Hyperfine Structure of Antihydrogen
The ASACUSA CUSP collaboration at the Antiproton Decelerator (AD) of CERN is
planning to measure the ground-state hyperfine splitting of antihydrogen using
an atomic spectroscopy beamline. We describe here the latest developments on
the spectroscopy apparatus developed to be coupled to the antihydrogen
production setup (CUSP).Comment: Proceedings of the 11th International Conference on Low Energy
Antiproton Physics (LEAP 2013) held in Uppsala, Sweden, 10 to 15 June, 201
PERCEIVE: PrEdiction of Risk and Communication of outcome following major lower limb amputation - a collaboratIVE study
Major Lower Limb Amputation (MLLA) is a life changing event with significant morbidity and mortality. Inaccurate risk prediction can lead to poor decision making, resulting in delay to definitive surgery, or undertaking amputation when not in the patient’s best interest. We aim to answer: In adult patients undergoing MLLA for chronic limb threatening ischaemia or diabetes, how accurately do health care professionals prospectively predict outcomes after MLLA, and how does this compare to existing prediction tools?
Methods
A multicentre prospective observational cohort study is being delivered through the Vascular and Endovascular Research Network. Dissemination was via an existing network of contacts and social media.
Consecutive data will be collected for seven months from site launch date, including demographic data and pre-operative outcome predictions from surgeons, anaesthetists, and allied healthcare professionals. Follow-up data will comprise 30-day (mortality, morbidity, MLLA revision, surgical site infection, and blood transfusion) and 1-year (mortality, MLLA revision and ambulation). The accuracy of surgeons’ predictions will be evaluated and compared to pre-existing risk prediction scoring tools.
Results
PERCEIVE launched on 01/10/2020 with 23 centres (16 UK, 7 international) registered to collect data. 50 other centres (27 UK, 23 international) have expressed interest/are pursuing local audit/ethical approval. We aim to collect data on clinicians estimate of outcomes for over 500 patients.
Discussion
This study will utilise a trainee research network to provide data on the accuracy of healthcare professionals’ predictions of outcomes following MLLA and compare this to the utility of existing prediction tools in this patient cohort
Clinical presentation and natural history of infantile-onset ascending spastic paralysis from three families with an ALS2 founder variant.
Biallelic mutations of the alsin Rho guanine nucleotide exchange factor (ALS2) gene cause a group of overlapping autosomal recessive neurodegenerative disorders including infantile-onset ascending hereditary spastic paralysis (IAHSP), juvenile primary lateral sclerosis (JPLS), and juvenile amyotrophic lateral sclerosis (JALS/ALS2), caused by retrograde degeneration of the upper motor neurons of the pyramidal tracts. Here, we describe 11 individuals with IAHSP, aged 2-48Â years, with IAHSP from three unrelated consanguineous Iranian families carrying the homozygous c.1640+1G>A founder mutation in ALS2. Three affected siblings from one family exhibit generalized dystonia which has not been previously described in families with IAHSP and has only been reported in three unrelated consanguineous families with JALS/ALS2. We report the oldest individuals with IAHSP to date and provide evidence that these patients survive well into their late 40s with preserved cognition and normal eye movements. Our study delineates the phenotypic spectrum of IAHSP and ALS2-related disorders and provides valuable insights into the natural disease course
An application of the self-potential (SP) method in archaeogeophysical prospection
Usage of the self-potential (SP) method on archaeological sites has been very limited and the phenomena that form the SP anomalies are not very well known. We believe that the vertical capillary water flows around stone walls that can be encountered frequently in archaeological sites, the porosity of the soil surrounding the archaeological structures, the moisture and clay ratio of the soil, and the changes in pH value of the soil, may form the SP anomalies. Moreover, an SP anomaly also may be formed if there is a moisture condition cutting the sulphuric and oxidized deposits under the earth. We determined, by our research, that the SP method can be very important, especially for determining the soil distribution and for archaeological research. The study was carried out on an Assyrian Tread Colony Period artificial hill in Acemhöyük, the chemical and physical structure of which was changed significantly after a large fire in approximately 1789±50 bc. The structure boundaries were found by interpreting the anomalies obtained from analytical modelling techniques, and an analysis of the SP mechanism of the area was attempted. In addition, the noise on the anomalies was eliminated by signal analysis techniques, thus enabling us to interpret the results more precisely. © 1996 John Wiley and Sons, Ltd
Is 2 mm a safe distance from the inferior alveolar canal to avoid neurosensory complications in implant surgery?
Aim: The aim of the present study was to compare the neurosensory complications related to implants inserted closer than 2 mm to the inferior alveolar canal (IAC) with those inserted further than 2 mm.Materials and Methods: A total of 474 implants in 314 patients placed posterior to mental foramen area were evaluated retrospectively on panoramic radiographs. Patients were divided into two groups regarding implant proximity to the IAC (Group 1, distance ≤2 mm, Group 2, distance >2 mm). Postoperative neurosensory complications (pain and paresthesia) were recorded. Chi-square test was used for statistical comparison and P ≤ 0.05 was considered significant.Results: One hundred and fifty-three implants (32.2%) were inserted closer than 2 mm to the IAC whereas 321 implants (67.8%) were inserted further than 2 mm. Three implants which had a distance of 0 mm to the IAC (0.63%) caused paresthesia after surgery. Implant distance to IAC did not show a significant difference regarding pain and paresthesia (P = 0.06 and P = 0.08, respectively).Conclusion: When 2 mm is considered as a safety distance, the distance of the implants to the IAC did not yield any statistical difference regarding postoperative neurosensory complications.Keywords: Dental implants, inferior alveolar nerve injury, neurosensory complicatio
Is 2 mm a safe distance from the inferior alveolar canal to avoid neurosensory complications in implant surgery?
Aim: The aim of the present study was to compare the neurosensory complications related to implants inserted closer than 2 mm to the inferior alveolar canal (IAC) with those inserted further than 2 mm
Pseudoexfoliative Glaucoma in a Patient with Toxic Optic Atrophy and Cupping
A 57-year-old man, who had developed bilateral symmetric optic atrophy and cupping due to methanol intoxication
nine years ago, noticed slowly progressive visual impairment in the left eye (OS). In ophthalmic examination, visual acuity
was 20/60 in the right eye (OD) and ‘hand motion’ in OS. Intraocular pressure was 20 in OD and 28mmHg in OS.
Anterior segment biomicroscopy showed bilateral pseudoexfoliation, more intense in OS. Ophthalmoscopy revealed
bilaterally deep and wide cupping with cup-to-disc ratios of 8/10 in OD and approximately 10/10 in OS. Based on these
findings, the diagnosis of left pseudoexfoliative glaucoma, in addition to bilateral toxic optic atrophy and cupping, was
made. Pathological optic-disc cupping may be caused by many conditions other than glaucoma. In these cases, glaucoma
may aggravate the both cupping and atrophy. (Turk J Ophthalmol 2011; 41: 256-9
Recommended from our members
The regulation and signalling of anti-Müllerian hormone in human granulosa cells: relevance to polycystic ovary syndrome.
STUDY QUESTION: What prevents the fall in anti-Müllerian hormone (AMH) levels in polycystic ovary syndrome (PCOS) and what are the consequences of this for follicle progression in these ovaries? SUMMARY ANSWER: Exposure of granulosa cells (GCs) to high levels of androgens, equivalent to that found in PCOS, prevented the fall in AMH and was associated with dysregulated AMH-SMAD signalling leading to stalled follicle progression in PCOS. WHAT IS KNOWN ALREADY: In normal ovaries, AMH exerts an inhibitory role on antral follicle development and a fall in AMH levels is a prerequisite for ovulation. Levels of AMH are high in PCOS, contributing to the dysregulated follicle growth that is a common cause of anovulatory infertility in these women. STUDY DESIGN, SIZE, DURATION: Human KGN-GC (the cell line that corresponds to immature GC from smaller antral follicles (AF)) were cultured with a range of doses of various androgens to determine the effects on AMH production. KGN-GC were also treated with PHTPP (an oestrogen receptor β (ERβ) antagonist) to examine the relationship between AMH expression and the ratio of ERα:ERβ. The differential dose-related effect of AMH on gene expression and SMAD signalling was investigated in human granulosa-luteal cells (hGLC) from women with normal ovaries, with polycystic ovarian morphology (PCOM) and with PCOS. KGN-GC were also cultured for a prolonged period with AMH at different doses to assess the effect on cell proliferation and viability. PARTICIPANTS/MATERIALS, SETTING, METHODS: AMH protein production by cells exposed to androgens was measured by ELISA. The effect of PHTPP on the mRNA expression levels of AMH, ERα and ERβ was assessed by real-time quantitative PCR (qPCR). The influence of AMH on the relative mRNA expression levels of aromatase, AMH and its receptor AMHRII, and the FSH and LH receptor (FSHR and LHR) in control, PCOM and PCOS hGLCs was quantified by qPCR. Western blotting was used to assess changes in levels of SMAD proteins (pSMAD-1/5/8; SMAD-4; SMAD-6 and SMAD-7) after exposure of hGLCs from healthy women and women with PCOS to AMH. The ApoTox-Glo Triplex assay was used to evaluate the effect of AMH on cell viability, cytotoxicity and apoptosis. MAIN RESULTS AND THE ROLE OF CHANCE: Testosterone reduced AMH protein secreted from KGN-GC at 10-9-10-7 M (P < 0.05; P < 0.005, multiple uncorrected comparisons Fishers least squares difference), but at equivalent hyperandrogenemic levels no change was seen in AMH levels. 5α-DHT produced a significant dose-related increase in AMH protein secreted into the media (P = 0.022, ANOVA). Increasing the mRNA ratio of ERα:ERβ produced a corresponding increase in AMH mRNA expression (P = 0.015, two-way ANOVA). AMH increased mRNA levels of aromatase (P < 0.05, one-way ANOVA) and FSHR (P < 0.0001, one-way ANOVA) in hGLCs from women with PCOM, but not from normal cells or PCOS (normal n = 7, PCOM n = 5, PCOS n = 4). In contrast to hGLCs from ovulatory ovaries, in PCOS AMH reduced protein levels (cell content) of stimulatory pSMAD-1/5/8 and SMAD-4 but increased inhibitory SMAD-6 and -7 (P < 0.05, normal n = 6, PCOS n = 3). AMH at 20 and 50 ng/ml decreased KGN-GC cell proliferation but not viability after 8 days of treatment (P < 0.005, two-way ANOVA). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Luteinised GC from women undergoing IVF have a relatively low expression of AMH/AMHRII but advantageously continue to display responses inherent to the ovarian morphology from which they are collected. To compensate, we also utilised the KGN cell line which has been characterised to be at a developmental stage close to that of immature GC. The lack of flutamide influence on testosterone effects is not in itself sufficient evidence to conclude that the effect on AMH is mediated via conversion to oestrogen, and the effect of aromatase inhibitors or oestrogen-specific inhibitors should be tested. The effect of flutamide was tested on testosterone but not DHT. WIDER IMPLICATIONS OF THE FINDINGS: Normal folliculogenesis and ovulation are dependent on the timely reduction in AMH production from GC at the time of follicle selection. Our findings reveal for the first time that theca-derived androgens may play a role in this model but that this inhibitory action is lost at levels of androgens equivalent to those seen in PCOS. The AMH decline may either be a direct effect of androgens or an indirect one via conversion to oestradiol and acting through the upregulation of ERα, which is known to stimulate the AMH promoter. Interestingly, the ability of GCs to respond to this continually elevated AMH level appears to be reduced in cells from women with PCOS due to an adaptive alteration in the SMAD signalling pathway and lower expression of AMHRII, indicating a form of 'AMH resistance'. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the Thomas Addison Scholarship, St Georges Hospital Trust. The authors report no conflict of interest in this work and have nothing to disclose. TRIAL REGISTRATION NUMBER: N/A