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A key challenge in cultural heritage (CH) sites visualization is to provide models and tools that effectively integrate the content of a CH data with domain-specific knowledge so that the users can query, interpret and consume the visualized information. Moreover, it is important that the intelligent visualization systems are interoperable in the semantic web environment and thus, capable of establishing a methodology to acquire, integrate, analyze, generate and share numeric contents and associated knowledge in human and machine-readable Web. In this paper, we present a model, a methodology and a software Web-tools that support the coupling of the 2D/3D Web representation with the knowledge graph database of Xlendi shipwreck. The Web visualization tools and the knowledge-based techniques are married into a photogrammetry driven ontological model while at the same time, user-friendly web tools for querying and semantic consumption of the shipwreck information are introduced. [ABSTRACT FROM AUTHOR]

This article proposes a technique to simplify the cementation of indirect restorations by exploiting the advantageous properties of bulk-fill composites (BFCs). The proposed technique consists of using a thin layer of a high-viscosity (HV) BFC in the interproximal margins of the preparation and applying low-viscosity (LV) resin luting agents (RLAs) to the rest of the prepared surface. The application of the HV BFC limits the extrusion of the LV RLAs in the interproximal area, deviating the excesses of LV RLAs only on the vestibular and lingual side. This deviation allows the management and control of the excess material in complicated interproximal spaces, simplifying the cementation procedure of indirect restorations and achieving a reliable final result in terms of removing excess in a safe and repeatable way. This technical report provides an alternative clinical approach for cementing indirect restorations using the consistency and viscosity of different RLAs.

An extremely rare case presenting two bilateral transposed and infraosseus impacted maxillary canines was treated with a combined two-step periodontal and orthodontic technique. The canines were transposed mesially and buccally to the lateral incisors, close to the midline and in a horizontal position. Direct orthodontically guided traction of the teeth toward the center of the alveolar ridge was not possible due to the roots of the lateral incisors. The procedure consisted of two distinct treatment phases for each side preceded by an initial orthodontic treatment to achieve the palatal inclination of the roots of the lateral incisors, creating a parallel buccal inclination of the crowns. This approach provided a submucosal buccal space into which the canines could be moved buccally and distally, avoiding any contact with the roots of the lateral incisors. In the first phase, the transposed canines were guided distally. When the canines, still in a submucosal position, were freed from those obstacles, the second phase was begun. The teeth were exposed, permitting the orthodontically guided traction toward the center of the ridge, simulating a proper physiologic eruption alignment pattern in the arch. The combined two-step periodontal and orthodontic approach used to treat two bilateral transposed and infraosseus impacted maxillary canines was extremely successful, resulting in adequate alignment in the arch associated with a physiologic sulcus depth, adequate keratinized tissue width, and absence of marginal recession at the end of the active treatment and 5 years postsurgery.

The present study investigates the kinetic disposition with focus on the racemization, glucuronidation capacity and the transplacental transfer of lorazepam in term parturients during labor. The study was conducted on 10 healthy parturients aged 18-37 years with a gestational age of 36-40.1 weeks, treated with a single oral dose of 2 mg racemic lorazepam 2-9 h before delivery. Maternal venous blood and urine samples were obtained over a 0-48 h interval and the umbilical cord sample was obtained immediately after clamping. Lorazepam enantiomers were determined in plasma and urine samples by LC-MS/MS using a Chiralcel OD-R column. In vitro racemization of lorazepam required the calculation of the pharmacokinetic parameters as isomeric mixtures. The data were fitted to two-compartment model and the pharmacokinetic parameters are reported as means (95% CI): t(1/2a) 3.2h (2.6-3.7 h), K(a) 0.23 h(-1) (0.19-0.28 h(-1)), t(1/2) 10.4h (9.4-11.3h), beta 0.068 h(-1) (0.061-0.075h(-1)), AUC(0-infinity) 175.3(ngh)/ml (145.7-204.8(ngh)/ml), Cl/F 2.6 ml/(minkg) (2.3-2.9 ml/(minkg)), Vd/F178.8l (146.5-211.1l), Fel 0.3% (0.1-0.5%), and Cl(R) 0.010 ml/(minkg) (0.005-0.015 ml/(minkg)). Placental transfer of lorazepam evaluated as the ratio of vein umbilical/maternal vein plasma concentrations, obtained as an isomeric mixture, was 0.73 (0.52-0.94). Pregnancy changes the pharmacokinetics of lorazepam, with an increase in the apparent distribution volume, an increase in apparent oral clearance, and a reduction of elimination half-life. The increase in oral clearance may indicate an increase in glucuronidation capacity, with a possible reduction in the plasma concentrations of drugs depending on glucuronidation capacity as the major metabolic pathway.

A LC/MS/MS method for the quantitative determination of lorazepam in human plasma and urine samples was developed and validated. The enantioselective assay allowed to separate the enantiomers and to verify the stereochemical instability of lorazepam. The linearity assessed for lorazepam unchanged was 0.2-20 ng of each enantiomer/ml plasma and 0.2-15 ng of each enantiomer/ml urine. The linearity assessed for total lorazepam (after enzymatic hydrolysis) was 1-30 ng of each enantiomer/ml plasma and 10-150 ng of each enantiomer/ml urine. The coefficients of variation obtained for the intra- and interassay precision were less than 15%. The method was applied to the investigation of the kinetic disposition and metabolism of racemic lorazepam administered as a single oral dose of 2 mg to a parturient. The occurrence of racemization required the calculation of the pharmacokinetic parameters as enantiomeric mixtures of lorazepam (t(1/2a) 3.5h; K(a) 0.198 ngh(-1); t(1/2) 11.5h; beta 0.060 h(-1); AUC(0-infinity) 192.1ngh/ml; CLt/f 2.41ml/minkg; Vd/f 173.5l; Fel 0.41%, and Cl(R) 0.0099 ml/minkg) and its metabolite lorazepam-glucuronide (t(1/2f) 1.2h; K(f) 0.578 h(-1); t(1/2) 16.6h; beta 0.042 h(-1); AUC(0-infinity) 207.6 ngh/ml; Fel 51.80%, and Cl(R) 98.32 ml/minkg). However, the determined confidence limits make the method suitable for application to clinical pharmacokinetic studies, even if the quantification of both the enantiomers is required.

The aim of the present study was to investigate the stereoselectivity in the kinetic disposition and the transplacental distribution of bupivacaine in term parturients during labor. Maternal age ranged from 18-37 years and fetal gestational age from 37.6-41.5 weeks. Healthy parturients (n = 23) received epidural 0.5% racemic bupivacaine alone (group A) or combined with epinephrine (group B). Maternal venous blood was sampled at regular intervals until 8 h after drug administration and umbilical venous blood was obtained at delivery. Bupivacaine enantiomers were determined in plasma samples by HPLC using a Chiralcel(R) OD-R column and a UV detector. One- or two-compartment models were fitted to data and differences between the (+)-(R) and (-)-(S) enantiomers were compared with the paired Wilcoxon test (P< 0.05). The influence of epinephrine was evaluated using the unpaired Mann-Whitney test (P< 0.05). The disposition of bupivacaine in maternal plasma was stereoselective, with higher V(d/f) (140.60 vs. 132.81 L for group A and 197.86 vs. 169.46 L for group B) and C(l/f) (29.00 vs. 25.43 L/h for group A and 33.15 vs. 26.39 L/h for group B) and lower t(1/2)beta (3.24 vs. 3.30 h for group A and 4.36 vs. 4.45 h for group B) being observed for (+)-(R)-bupivacaine. The combined administration of epinephrine resulted in higher V(d/f) (197.86 vs. 140.60 L for (+)-(R) and 169.46 vs. 132.81 L for (-)-(S)) and t(1/2)beta values (4.36 vs. 3.24 h for (+)-(R) and 4.45 vs. 3.30 h for (-)-(S)). The transplacental distribution of bupivacaine was stereoselective only when bupivacaine was administered without epinephrine (group B), with a higher cord blood/maternal blood ratio being observed for (-)-(S)-bupivacaine (0.40 vs. 0.35). Chirality 16:65-71, 2004., (Copyright 2004 Wiley-Liss, Inc.)

R,S-sotalol, a ss-blocker drug with class III antiarrhythmic properties, is prescribed to patients with ventricular, atrial and supraventricular arrhythmias. A simple and sensitive method based on HPLC-fluorescence is described for the quantification of R,S-sotalol racemate in 500 microl of plasma. R,S-sotalol and its internal standard (atenolol) were eluted after 5.9 and 8.5 min, respectively, from a 4-micron C18 reverse-phase column using a mobile phase consisting of 80 mM KH2PO4, pH 4.6, and acetonitrile (95:5, v/v) at a flow rate of 0.5 ml/min with detection at lambdaex = 235 nm and lambdaem = 310 nm, respectively. This method, validated on the basis of R,S-sotalol measurements in spiked blank plasma, presented 20 ng/ml sensitivity, 20-10,000 ng/ml linearity, and 2.9 and 4.8% intra- and interassay precision, respectively. Plasma sotalol concentrations were determined by applying this method to investigate five high-risk patients with atrial fibrillation admitted to the Emergency Service of the Medical School Hospital, who received sotalol, 160 mg po, as loading dose. Blood samples were collected from a peripheral vein at zero, 0.5, 1.0, 1.5, 2.0, 3.0, 4. 0, 6.0, 8.0, 12.0 and 24.0 h after drug administration. A two-compartment open model was applied. Data obtained, expressed as mean, were: C MAX = 1230 ng/ml, T MAX = 1.8 h, AUC T = 10645 ng h-1 ml-1, Kab = 1.23 h-1, alpha = 0.95 h-1, ss = 0.09 h-1, t((1/2))ss = 7.8 h, ClT/F = 3.94 ml min-1 kg-1, and Vd/F = 2.53 l/kg. A good systemic availability and a fast absorption were obtained. Drug distribution was reduced to the same extent in terms of total body clearance when patients and healthy volunteers were compared, and consequently elimination half-life remained unchanged. Thus, the method described in the present study is useful for therapeutic drug monitoring purposes, pharmacokinetic investigation and pharmacokinetic-pharmacodynamic sotalol studies in patients with tachyarrhythmias.