589 research outputs found
Phosphate concentration in ophthalmic corticoid preparations
Background: Topical preparations, high in phosphate, may cause calcification when used on a damaged corneal surface. The knowledge of the phosphate concentration in medications helps to prevent corneal calcifications. Our study gives an overview of the amount of phosphate contained in ophthalmic corticoid preparations. Methods: Samples of 38 commercially available corticoid preparations were tested. The quantification of phosphate was performed using the molybdate method on a Modular P autoanalyzer. Results: 18 of 38 preparations (47%) had a phosphate concentration above physiological levels (>1.45mmol/l). It varied greatly, and ranged from less than 0.1mmol/l (18 preparations) to 62.6mmol/l. The corticoids that were tested included betamethasone sodium phosphate (18.3-35.5mmol/l), dexamethasone (0.1-17.6mmol/l), dexamethasone sodium phosphate (<0.1-62.6mmol/l), fluorometholone (<0.1-22.5mmol/l), and prednisolone acetate (<0.1-0.5mmol/l). Conclusions: The phosphate concentration in corticoid-phosphate formulations varies greatly, and is mainly determined by the chosen buffer. The prednisolone acetate preparations showed physiological phosphate concentrations. For a treatment on a damaged corneal surface, preparations with physiological phosphate concentrations should be use
Phosphate concentration in artificial tears
Background: Irrigating solutions and eye drops may contain phosphates as part of their buffer system. In the presence of epithelial keratopathy, a high concentration of phosphate favours corneal calcification. Knowledge of the phosphate concentration in artificial tear products helps to prevent this sight-threatening complication. This study gives an overview on the amount of phosphate contained in artificial tears. Methods: Fifty-nine samples of commercially available artificial tear preparations were tested. The quantification of phosphate was performed using the molybdate method on a Modular P autoanalyzer. Results: Twenty-six of 59 (44%) artificial tear products had a phosphate concentration above physiological levels (>1.45mmol/l). A phosphate concentration above 25mmol/l was found in nine products (15%), a concentration higher than 50mmol/l in three (5%). Conclusions: Many artificial tear formulations contain unphysiological levels of phosphate, but very high concentrations are found only in a few products. These preparations have the potential to favour the formation of insoluble crystalline calcium phosphate deposits when used on a damaged corneal surface, and should therefore be used cautiousl
Evaluation of early and late presentation of patients with ocular mucous membrane pemphigoid to two major tertiary referral hospitals in the United Kingdom
PURPOSE: Ocular mucous membrane pemphigoid (OcMMP) is a sight-threatening autoimmune disease in which referral to specialists units for further management is a common practise. This study aims to describe referral patterns, disease phenotype and management strategies in patients who present with either early or established disease to two large tertiary care hospitals in the United Kingdom.\ud
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PATIENTS AND METHODS: In all, 54 consecutive patients with a documented history of OcMMP were followed for 24 months. Two groups were defined: (i) early-onset disease (EOD:<3 years, n=26, 51 eyes) and (ii) established disease (EstD:>5 years, n=24, 48 eyes). Data were captured at first clinic visit, and at 12 and 24 months follow-up. Information regarding duration, activity and stage of disease, visual acuity (VA), therapeutic strategies and clinical outcome were analysed.\ud
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RESULTS: Patients with EOD were younger and had more severe conjunctival inflammation (76% of inflamed eyes) than the EstD group, who had poorer VA (26.7%=VA<3/60, P<0.01) and more advanced disease. Although 40% of patients were on existing immunosuppression, 48% required initiation or switch to more potent immunotherapy. In all, 28% (14) were referred back to the originating hospitals for continued care. Although inflammation had resolved in 78% (60/77) at 12 months, persistence of inflammation and progression did not differ between the two phenotypes. Importantly, 42% demonstrated disease progression in the absence of clinically detectable inflammation.\ud
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CONCLUSIONS: These data highlight that irrespective of OcMMP phenotype, initiation or escalation of potent immunosuppression is required at tertiary hospitals. Moreover, the conjunctival scarring progresses even when the eye remains clinically quiescent. Early referral to tertiary centres is recommended to optimise immunosuppression and limit long-term ocular damage.\ud
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Environmental changes and violent conflict
This letter reviews the scientific literature on whether and how environmental changes affect the risk of violent conflict. The available evidence from qualitative case studies indicates that environmental stress can contribute to violent conflict in some specific cases. Results from quantitative large-N studies, however, strongly suggest that we should be careful in drawing general conclusions. Those large-N studies that we regard as the most sophisticated ones obtain results that are not robust to alternative model specifications and, thus, have been debated. This suggests that environmental changes may, under specific circumstances, increase the risk of violent conflict, but not necessarily in a systematic way and unconditionally. Hence there is, to date, no scientific consensus on the impact of environmental changes on violent conflict. This letter also highlights the most important challenges for further research on the subject. One of the key issues is that the effects of environmental changes on violent conflict are likely to be contingent on a set of economic and political conditions that determine adaptation capacity. In the authors' view, the most important indirect effects are likely to lead from environmental changes via economic performance and migration to violent conflict. © 2012 IOP Publishing Ltd
Levels of rna for TNF-α and receptors during the prereplicative period of liver regeneration
During the prereplicative period of liver regeneration the changes of the tnRNA contents for tumor necrosis factor-α (TNF-α) and its receptors were examined in total liver RNA with the help of reverse transcriptase-polymera.se chain reaction (RT-PCR) and compared with those after sham operation or stimulation with lipopolysaccharide (LPS). In regenerating liver all the changes are nearly synchronous with a slight delay (or the TNF receptor RNAs. The mRNA levels reach their maximum at 1–3 h after operation and exceed the values for intact animals about ten-fold. The corresponding changes induced by sham operation are quantitatively less than those in the regenerating liver and manifest themselves at the end of the prereplicative period. LPS stimulation induced an increase of TNF-α and TNF receptor production comparable with during regeneration. Analysis of the expression of the 55 kDa TNF receptor revealed qualitative changes, e. g. an increased polyadenylation and an imbalance between the amplification of the whole molecule and its 5'-terminal half pointing to as yet unidentified changes at the 3' end of the molecule.Протягом пререплікативного періоду регенерації печінки спостерігалися зміни, вмісту мРНК фактора некроза пухлини (TNF-α) i його рецепторів у сумарній РНК печінки за допомогою зворотної транскрипції та полімеразної ланцюгової реакції. Для порівняння ці ж величини визначали у печінці теля несправжньої операції або ліпополісахаридної стимуляції. У регенеруючі печінці вci зміни майже синхронні, з невеликим запізненням для РНК рецепторів TNF. Рівні мРНК досягають максимальних значень через 1–3 год. теля операції i приблизно у 10 разів перевищують такі для штатних тварин. Зміни, викликані несправжньою операщею, меньші за величиною, ніж при регенерації, i проявляються у кінці пререплікативного перюду. Стимуляція ліпополісахаридами призводить до росту продукції TNF-α i його рецепторів, порівнянно з таким при регенерації. Аналіз мРНК рецептора TNF масою 55 000 засвідчив якісні зміни, у тому числі збільшення поліаденілювання, i невідповідність ампліфікації щодо молекули та и частини, прилеглої до 5'-кінця, що вказує на поки що не визначені зміни на З'-кінці молекули.В течении пререпликативного периода регенерации печени наблюдались изменения, содержания мРНК фактора некроза опухоли (TNF α ) и его рецепторов в суммарной РНК печени с помощью обратной транскрипции и полимеразной цепной реакции. Для сравнения эти же величины определяли в печени теленка псевдооперации или липополисахаридный стимуляции. В регенерирующие печени вcе изменения почти синхронные, с небольшим опозданием для РНК рецепторов TNF . Уровни мРНК достигают максимальных значений через 1–3 час. теленок операции i примерно в 10 раз превышают таковые для штатных животных. Изменения, вызванные ложной операщею , меньшие по величине , чем при регенерации, и проявляются в конце пререпликативного периода . Стимуляция липополисахаридами приводит к росту продукции TNF -α и его рецепторов, по сравнению с таковым при регенерации. Анализ мРНК рецептора TNF массой 55000 показал качественные изменения, в том числе увеличение полиаденилирования , и несоответствие амплификации по молекулы и и части , прилегающей к 5' - конца , что указывает на пока не определены изменения на З' - конце молекулы
Prototype Lead Tungstate Calorimeter Test for TPEX
Tests of a prototype lead tungstate calorimeter were made over two weeks at
the end of September, 2019, at the DESY II Test Beam Facility in Hamburg,
Germany. The purpose of these tests was to gain experience with the
construction, operation, and performance of a simple lead tungstate
calorimeter, and also to compare a traditional triggered readout scheme with a
streaming readout approach. These tests are important for the proposed
Two-Photon Exchange experiment at the DESY test beam facility and for work
towards a future electromagnetic calorimeter that could be used in an
Electron-Ion Collider detector. Details on all aspects of the test, the
subsequent analysis, and the results are presented.Comment: 7 pages, 15 figure
A Large-Scale FPGA-Based Trigger and Dead-Time Free DAQ System for the Kaos Spectrometer at MAMI
The Kaos spectrometer is maintained by the A1 collaboration at the Mainz
Microtron MAMI with a focus on the study of (e,e'K^+) coincidence reactions.
For its electron-arm two vertical planes of fiber arrays, each comprising
approximately 10 000 fibers, are operated close to zero degree scattering angle
and in close proximity to the electron beam. A nearly dead-time free DAQ system
to acquire timing and tracking information has been installed for this
spectrometer arm. The signals of 144 multi-anode photomultipliers are collected
by 96-channel front-end boards, digitized by double-threshold discriminators
and the signal time is picked up by state-of-the-art F1 time-to-digital
converter chips. In order to minimize background rates a sophisticated trigger
logic was implemented in newly developed Vuprom modules. The trigger performs
noise suppression, signal cluster finding, particle tracking, and coincidence
timing, and can be expanded for kinematical matching (e'K^+) coincidences. The
full system was designed to process more than 4 000 read-out channels and to
cope with the high electron flux in the spectrometer and the high count rate
requirement of the detectors. It was successfully in-beam tested at MAMI in
2009.Comment: Contributed to 17th IEEE Real Time Conference (RT10), Lisbon, 24-28
May 201
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