110 research outputs found
Mechanisms of goethite dissolution in the presence of desferrioxamine B and Suwannee River fulvic acid at pH 6.5
Siderophores are Fe3+ specific low MW chelating ligands secreted by microorganisms in response to Fe stress. Low MW organic acids such as oxalate have been shown to enhance siderophore mediated dissolution of Fe3+ oxides. However, the effect of fulvic acid presence on siderophore function remains unknown. We used batch dissolution experiments to investigate Fe release from goethite in the goethite-fulvic acid desferrioxamine B (goethite-SRFA-DFOB) ternary system. Experiments were conducted at pH 6.5 while varying reagent addition sequence. FTIR and UV-Vis spectroscopy were employed to characterise the Fe-DFOB, Fe-SRFA and DFOB–SRFA complexes. Iron released from goethite in the presence of SRFA alone was below detection limit. In the presence of both SRFA and DFOB, dissolved Fe increased with reaction time, presence of the DFOB-SRFA complex, and where SRFA was introduced prior to DFOB. FTIR data show that in the ternary system, Fe3+ is complexed primarily to oxygen of the DFOB hydroxamate group, whilst the carboxylate C=O of SRFA forms an electrostatic association with the
terminal NH3+ of DFOB. We propose that SRFA sorbed to goethite lowers the net positive charge of the oxide surface, thus facilitating adsorption of cationic DFOB and subsequent Fe3+ chelation and release. Furthermore, the sorbed SRFA weakens Fe-O bonds at the goethite surface, increasing the population of kinetically labile Fe. This work demonstrates the positive, though indirect role of SRFA in increasing the bioavailability of Fe3+
Effect of implant therapy on oral health-related quality of life (OHIP-49), health status (SF-36), and satisfaction of patients with several agenetic teeth:Prospective cohort study
BACKGROUND: Effect of fixed prosthodontics on patients with several agenetic teeth is not well understood. PURPOSE: To assess the effect of implant-based fixed prosthodontics on oral health-related quality of life (OHRQoL), general health status, and satisfaction regarding dental appearance, ability to chew and speech in patients with several agenetic teeth. MATERIALS AND METHODS: For this prospective cohort study, all patients (≥18 years) with several agenetic teeth who were scheduled for treatment with fixed dental implants between September 2013 and July 2015 at our department were approached. Participants received a set of questionnaires before and 1 year after implant placement to assess OHRQoL (OHIP-NL49), general health status (SF-36), and satisfaction regarding dental appearance, ability to chew and speech. RESULTS: About 25 out of 31 eligible patients (10 male, 15 female; median age: 20 [19;23] years; agenetic teeth: 7 [5;10]) were willing to participate. Pre- and post-treatment OHIP-NL49 sum-scores were 38 [28;56] and 17 [7;29], respectively (P .05). CONCLUSIONS: Treatment with implant-based fixed prosthodontics improves OHRQoL and satisfaction with dental appearance, ability to chew and speech, while not affecting general health status
DESAIN SOLDIER PILE DENGAN PLAXIS MENGGUNAKAN PEMODELAN HARDENING SOIL
Semakin terbatasnya lahan dan mahalnya harga tanah di lokasi strategis di kota-kota besar
seperti di Jakarta mengakibatkan dibangunnya gedung tinggi untuk memanfaatkan semaksimal
mungkin lahan yang ada. Semakin tinggi suatu gedung dibangun, semakin luas pula kebutuhan
parkir yang harus disediakan. Untuk memenuhi kebutuhan parkir tersebut basement merupakan
altematif penyelesaian. Masalah utama dalam pembangunan basement yang sering dihadapi
adalah adanya bangunan tinggi di sekitamya sehingga dibutuhkan struktur dinding penahan
tanah yang kokoh Dalam pelaksanaan ga/ian basement pada suatu proyek, pada prinsipnya harus
menjaga stabi/itas tanah. Untuk mengatasi masalah tersebut di atas, digunakan dinding soldier
pile yang merupakan rangkaian atau barisan bored pile yang terbuat dari beton yang dicor di
tempat (cast in situ). Ga/ian basement proyek The City Center Office Park, Jakarta Pusat,
mempunyai kedalaman -16,5 m di bawah muka tanah. Dari hasil penye/idikan tanah diketahui
bahwa tanah berupa lempung berlanau yang sebagian tersedimentasi dan secara bergantian
disisipi oleh pasir yang sangat pad at sampai kedalaman 30 m. Soldier pile yang digunakan
berdiameter 1 m dan dipancang sampai kedalaman 32,5 m. Ana/isis dilakukan menggunakan
program PLAXIS menggunakan pemodelan hardening soil dan program komputer Excel.
Perhitungan meliputi deformasi maksimum dan gaya-gaya dalam dari struktur dinding soldier
pile. Didapatkan deformasi maksimum soldier pile sebesar 0,11043 m. Dari hasil ana/isis
menurljukkan bahwa struktur penahan tanah perlu dibuat untuk menahan beban lateral tanah.
Hasil dari ana/isis PLAXIS juga memberikan perhitungan yang dapat diterima dan cukup akurat
Three-dimensional computer-guided implant placement in oligodontia
Abstract Background The aim of computer-designed surgical templates is to attain higher precision and accuracy of implant placement, particularly for compromised cases. Purpose The purpose of this study is to show the benefit of a full three-dimensional virtual workflow to guide implant placement in oligodontia cases where treatment is challenging due compromised bone quantity and limited interdental spaces. Patient and methods A full, digitalized workflow was performed for implant placement in two oligodontia patients. Accuracy was assessed by calculating the coordinates of the entry point (shoulder) and apex (tip) as well as the angular deviation of the planned and actual implants. Results Implant placement could be well performed with the developed computer-designed templates in oligodontia. Mean shoulder deviation was 1.41 mm (SD 0.55), mean apical deviation was 1.20 mm (SD 0.54) and mean angular deviation was 5.27° (SD 2.51). Conclusion Application of computer-designed surgical templates, as described in this technical advanced article, aid in predictable implant placement in oligodontia where bone quantity is scarce and interdental spaces are limited
Guidance on the Selection of Appropriate Indicators for Quantification of Antimicrobial Usage in Humans and Animals
An increasing variety of indicators of antimicrobial usage has become available in human and veterinary medicine, with no consensus on the most appropriate indicators to be used. The objective of this review is therefore to provide guidance on the selection of indicators, intended for those aiming to quantify antimicrobial usage based on sales, deliveries or reimbursement data. Depending on the study objective, different requirements apply to antimicrobial usage quantification in terms of resolution, comprehensiveness, stability over time, ability to assess exposure and comparability. If the aim is to monitor antimicrobial usage trends, it is crucial to use a robust quantification system that allows stability over time in terms of required data and provided output; to compare usage between different species or countries, comparability must be ensured between the different populations. If data are used for benchmarking, the system comprehensiveness is particularly crucial, while data collected to study the association between usage and resistance should express the exposure level and duration as a measurement of the exerted selection pressure. Antimicrobial usage is generally described as the number of technical units consumed normalized by the population at risk of being treated in a defined period. The technical units vary from number of packages to number of individuals treated daily by adding different levels of complexity such as daily dose or weight at treatment. These technical units are then related to a description of the population at risk, based either on biomass or number of individuals. Conventions and assumptions are needed for all of these calculation steps. However, there is a clear lack of standardization, resulting in poor transparency and comparability. By combining study requirements with available approaches to quantify antimicrobial usage, we provide suggestions on the most appropriate indicators and data sources to be used for a given study objective
A modified method for measuring antibiotic use in healthcare settings: implications for antibiotic stewardship and benchmarking
Probiotics versus antibiotic decontamination of the digestive tract: infection and mortality
Purpose: Selective decontamination of the digestive tract (SDD) has been shown to decrease the infection rate and mortality in intensive care units (ICUs); Lactobacillus plantarum 299/299v plus fibre (LAB) has been used for infection prevention and does not harbour the potential disadvantages of antibiotics. The objective was to assess whether LAB is not inferior to SDD in infection prevention. Methods: Two hundred fifty-four consecutive ICU patients with expected mechanical ventilation ≥48 h and/or expected ICU stay ≥72 h were assigned to receive SDD: four times daily an oral paste (polymyxin E
PROGNOSTIC FACTORS IN PATIENTS WITH PRESSURE SORES IN A UNIVERSITY HOSPITAL IN SOUTHERN BRAZIL
Evaluation of LHP® (1% hydrogen peroxide) cream versus petrolatum and untreated controls in open wounds in healthy horses: a randomized, blinded control study
<p>Abstract</p> <p>Background</p> <p>Treatment and protection of wounds in horses can be challenging; protecting bandages may be difficult to apply on the proximal extremities and the body. Unprotected wounds carry an increased risk of bacterial contamination and subsequent infection which can lead to delayed wound healing. Topical treatment with antimicrobials is one possibility to prevent bacterial colonization or infection, but the frequent use of antimicrobials ultimately leads to development of bacterial resistance which is an increasing concern in both human and veterinary medicine.</p> <p>Methods</p> <p>Standardized wounds were created in 10 Standardbred mares. Three wounds were made in each horse. Two wounds were randomly treated with LHP<sup>® </sup>or petrolatum and the third wound served as untreated control. All wounds were assessed daily until complete epithelization. Protocol data were recorded on day 2, 6, 11, 16, 21 and 28. Data included clinical scores for inflammation and healing, photoplanimetry for calculating wound areas and swab cytology to assess bacterial colonization and inflammation. Bacterial cultures were obtained on day 2, 6 and 16.</p> <p>Results</p> <p>Mean time to complete healing for LHP<sup>® </sup>treated wounds was 32 days (95%CI = 26.9-37.7). Mean time to complete healing for petrolatum and untreated control wounds were 41.6 days (95%CI = 36.2-47.0) and 44.0 days (95%CI = 38.6-49.4) respectively. Wound healing occurred significantly faster in LHP<sup>® </sup>wounds compared to both petrolatum (p = 0.0004) and untreated controls (p < 0.0001). There was no significant difference in time for healing between petrolatum and untreated controls. Total scores for bacteria and neutrophils were significantly (p < 0.0001) lower for LHP<sup>® </sup>treated wounds compared to petrolatum from day 16 and onwards. <it>Staphylococcus aureus </it>and <it>Streptococcus zooepidemicus </it>were only found in cultures from petrolatum treated wounds and untreated controls.</p> <p>Conclusions</p> <p>Treatment with LHP<sup>® </sup>reduced bacterial colonization and was associated with earlier complete wound healing. LHP<sup>® </sup>cream appears to be safe and effective for topical wound treatment or wound protection.</p
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