A Retrospective Clinical Study on 1075 Lithium Disilicate CAD/CAM Veneers with Feather-Edge Margins Cemented on 105 Patients.

PURPOSE: To evaluate the clinical performance of lithium disilicate (LiDiSi) computer-aided- design/computer-assisted-manufacturing (CAD/CAM) veneers with feather-edge margins. METHODS: Over 4 years (2015-2019), 1075 LiDiSi veneers with feather-edge margins were fabricated with a fully digital workflow and cemented on 105 patients. The outcome variables were survival of the restorations, colour matching, quality of the ceramic surface, presence of marginal discolouration and marginal integrity. The last four variables were assessed using the modified California Dental Association (CDA) and Ryge criteria. RESULTS: The mean observation period was 30.8 months. The cumulative survival rate was 99.83%. At the last follow-up control, the colour matching of the surviving 1074 restorations was rated Alpha (1064 veneers, 99.06%) and Bravo (10 veneers, 0.94%); the ceramic surface was rated Alpha (1070 veneers, 99.62%) and Bravo (4 veneers, 0.38%); the marginal discolouration was rated Alpha (1069 veneers, 99.53%) and Bravo (5 veneers, 0.47%); and the marginal integrity was rated Alpha (1070 veneers, 99.62%) and Bravo (4 veneers, 0.38%). CONCLUSION: CAD/CAM LiDiSi veneers with feather-edge margins fabricated with a fully digital workflow showed good clinical performance in terms of survival, colour matching, ceramic surface, marginal discolouration and integrity. Further, prospective and long-term studies are needed to confirm these positive results.

Continuous Scan Strategy (CSS): A Novel Technique to Improve the Accuracy of Intraoral Digital Impressions.

PURPOSE: To present the results obtained with the "Continuous Scan Strategy" (CSS), a direct intraoral scanning technique based on the connection of the implant scan bodies (SBs) with thermoplastic resin. METHODS: 40 patients were restored with 45 long-span monolithic implant-supported zirconia restorations (10 partial prostheses [PP] and 35 full arches [FA]) fabricated via a full-digital workflow after the capture of an intraoral impression (Trios3®) using the CSS technique. The primary outcomes were the marginal adaptation and passive fit of the superstructures, checked at T0 (intraoral try-in of polyurethane or metal replica of the final prosthesis) and T1 (delivery of the final zirconia restoration). The secondary outcomes, registered at T2 (2 years after the delivery of the final prosthesis), were implant survival, prosthetic success, and complications. A throughout statistical analysis was performed. RESULTS: At T0, 40/45 replicas demonstrated a perfect passive fit and adaptation. At T1, one prosthesis had fractured, and at T2, an additional prosthesis had fractured and one had chipped. The implant survival rate was 100%. The prosthetic success was 93.3%. CONCLUSIONS: CSS seems to represent a viable option for capturing accurate intraoral digital impressions for the fabrication of precise long-span implant-supported restorations.

Accuracy of 6 Desktop 3D Printers in Dentistry: A Comparative In Vitro Study.

PURPOSE: To compare the accuracy of 6 desktop 3D printers in dentistry. METHODS: A parallelepiped (PP) with known geometry and holes of different diameters was designed and printed with 6 desktop 3D printers (Sheraprint 40®; Solflex 350®; Form 2®; MoonRay D75®; Vida HD®; XFAB 2000®). For each printer, 9 PPs were printed with proprietary materials; these PPs were not cured and underwent dimensional analysis by optical microscopy and precision probing. A file representative of a dentate model (DM) was also printed with the aforementioned printers. For each printer, 3 DMs were printed with the proprietary materials. These DMs were cured and after 1 month, scanned with a desktop scanner and superimposed on the virtual reference model, to investigate trueness. RESULTS: Dimensional analysis by optical microscopy and precision probing highlighted the reliability of the 3D printed models; errors were compatible with clinical use. However, both linear and diameter measurements revealed statistically significant differences between the machines. The trueness of the DMs 1 month after printing was low, suggesting that they underwent dimensional contraction over time, albeit with differences between the printers. CONCLUSIONS: The 3D printed models showed acceptable accuracy, although statistically significant differences were found among them.

Human immunology studies using organ donors: Impact of clinical variations on immune parameters in tissues and circulation.

Organ donors are sources of physiologically healthy organs and tissues for life-saving transplantation, and have been recently used for human immunology studies which are typically confined to the sampling of peripheral blood. Donors comprise a diverse population with different causes of death and clinical outcomes during hospitalization, and the effects of such variations on immune parameters in blood and tissues are not known. We present here a coordinate analysis of innate and adaptive immune components in blood, lymphoid (bone marrow, spleen, lymph nodes), and mucosal (lungs, intestines) sites from a population of brain-dead organ donors (2 months-93 years; n = 291) across eight clinical parameters. Overall, the blood of donors exhibited similar monocyte and lymphocyte content and low serum levels of pro-inflammatory cytokines as healthy controls; however, donor blood had increased neutrophils and serum levels of IL-8, IL-6, and MCP-1 which varied with cause of death. In tissues, the frequency and composition of monocytes, neutrophils, B lymphocytes and T cell subsets in lymphoid or mucosal sites did not vary with clinical state, and was similar in donors independent of the extent of clinical complications. Our results reveal that organ donors maintain tissue homeostasis, and are a valuable resource for fundamental studies in human immunology.

Reaction of the thermo-labile triazenide Na[tBu3SiNNNSiMe3] with CO2: formation of the imido carbonate (tBu3SiO)(Me3SiO)C[double bond, length as m-dash]N-SitBu3 and carbamine acid (tBu3SiO)CONH2.

The thermo-labile triazenide Na[tBu3SiNNNSiMe3] was prepared by the reaction of Me3SiN3 with Na(thf)2[SitBu3] in pentane at -78 °C. Treatment of Na[tBu3SiNNNSiMe3] with an excess of carbon dioxide in pentane at -78 °C yielded the imido carbonate (tBu3SiO)(Me3SiO)C[double bond, length as m-dash]N-SitBu3 and the carbamine acid (tBu3SiO)CONH2 along with other products. From the reaction solution we could isolate the imido carbonate (tBu3SiO)(Me3SiO)C[double bond, length as m-dash]N-SitBu3 and carbamine acid (tBu3SiO)CONH2. At first single crystals of the carbamine acid (tBu3SiO)CONH2 (triclinic, space group P1[combining macron]) were grown from this solution at room temperature. A second crop of crystals were obtained by concentrating the solution. The second charge consisted of the imido carbonate (tBu3SiO)(Me3SiO)C[double bond, length as m-dash]N-SitBu3 (monoclinic, space group P21/n).

Evidence of a field-induced Berezinskii-Kosterlitz-Thouless scenario in a two-dimensional spin-dimer system.

Two-dimensional (2D) systems with continuous symmetry lack conventional long-range order because of thermal fluctuations. Instead, as pointed out by Berezinskii, Kosterlitz and Thouless (BKT), 2D systems may exhibit so-called topological order driven by the binding of vortex-antivortex pairs. Signatures of the BKT mechanism have been observed in thin films, specially designed heterostructures, layered magnets and trapped atomic gases. Here we report on an alternative approach for studying BKT physics by using a chemically constructed multilayer magnet. The novelty of this approach is to use molecular-based pairs of spin S=½ ions, which, by the application of a magnetic field, provide a gas of magnetic excitations. On the basis of measurements of the magnetic susceptibility and specific heat on a so-designed material, combined with density functional theory and quantum Monte Carlo calculations, we conclude that these excitations have a distinct 2D character, consistent with a BKT scenario, implying the emergence of vortices and antivortices.

Derivation of the uncontrolled donation after circulatory determination of death protocol for New York city.

Evidence from Europe suggests establishing out-of-hospital, uncontrolled donation after circulatory determination of death (UDCDD) protocols has potential to substantially increase organ availability. The study objective was to derive an out-of-hospital UDCDD protocol that would be acceptable to New York City (NYC) residents. Participatory action research and the SEED-SCALE process for social change guided protocol development in NYC from July 2007 to September 2010. A coalition of government officials, subject experts and communities necessary to achieve support was formed. Authorized NY State and NYC government officials and their legal representatives collaboratively investigated how the program could be implemented under current law and regulations. Community stakeholders (secular and religious organizations) were engaged in town hall style meetings. Ethnographic data (meeting minutes, field notes, quantitative surveys) were collected and posted in a collaborative internet environment. Data were analyzed using an iterative coding scheme to discern themes, theoretical constructs and a summary narrative to guide protocol development. A clinically appropriate, ethically sound UDCDD protocol for out-of-hospital settings has been derived. This program is likely to be accepted by NYC residents since the protocol was derived through partnership with government officials, subject experts and community participants.

C5H4-BR2 bending in ferrocenylboranes: a delocalized through-space interaction between iron and boron.

A comparison of the molecular structures of mono-, di- and tetraborylated ferrocenes [Fc{B(R(1))(R(2))}] (R(1)/R(2)=Br/Br, Br/Fc, Br/Me, Me/Me, Me/OH, OMe/OMe), 1,1'-[fc{B(R(1))(R(2))}(2)] (R(1)/R(2)=Br/Br, Br/Me, OMe/OMe), and 1,1',3,3'-[Fe{C(5)H(3)(BMe(2))(2)}(2)] revealed the boryl substituent(s) to be bent out of the Cp ring plane towards the iron center. The corresponding dip angle alpha* decreases with decreasing Lewis acidity of the boron atom and with increasing degree of borylation at the ferrocene core. This trend is well reproduced by DFT calculations (including [FcBH(2)], not yet accessible experimentally). A Bader analysis of the electron density topology of [FcBH(2)] (alpha*=26.5 degrees ; BP86/TZVP) clearly showed that there is no direct iron-boron bonding in this compound. Instead, strongly delocalized orbital interactions have been identified that involve the boron p orbital, C(ipso) of the adjacent Cp ring, d orbitals at iron, and a through-space interaction with the second Cp ring. A second important factor is attractive electrostatic interactions, which are enhanced upon ligand bending. Cyclic voltammetric measurements on the series [FcBMe(2)], 1,1'-[fc(BMe(2))(2)], and 1,1',3,3'-[Fe{C(5)H(3)(BMe(2))(2)}(2)] indicate a substantial anodic shift in the oxidation potential of the central iron atom upon introduction of BMe(2) substituents. Addition of 4-dimethylaminopyridine (DMAP) does not just counterbalance this effect, but leads to a cathodic shift of the Fe(II)/Fe(III) redox transition far beyond the half-wave potential of parent ferrocene. In the Mossbauer spectra, a continuous decrease in the quadrupole splitting (QS) is observed upon going from parent ferrocene to [FcBMe(2)], to 1,1'-[fc(BMe(2))(2)], and to 1,1',3,3'-[Fe{C(5)H(3)(BMe(2))(2)}(2)]. In contrast, no significant differences are found between the QS values of ferrocene, [Fc(BMe(2)-DMAP)], and 1,1'-[fc(BMe(2)-DMAP)(2)].

Structure characterization of human serum proteins in solution and dry state.

The present report describes application of advanced analytical methods to establish correlation between changes in human serum proteins of patients with coronary atherosclerosis (protein metabolism) before and after moderate beer consumption. Intrinsic fluorescence, circular dichroism (CD), differential scanning calorimetry and hydrophobicity (So) were used to study human serum proteins. Globulin and albumin from human serum (HSG and HSA, respectively) were denatured with 8 m urea as the maximal concentration. The results obtained provided evidence of differences in their secondary and tertiary structures. The thermal denaturation of HSA and HSG expressed in temperature of denaturation (Td, degrees C), enthalpy (DeltaH, kcal/mol) and entropy (DeltaS kcal/mol K) showed qualitative changes in these protein fractions, which were characterized and compared with fluorescence and CD. Number of hydrogen bonds (n) ruptured during this process was calculated from these thermodynamic parameters and then used for determination of the degree of denaturation (%D). Unfolding of HSA and HSG fractions is a result of promoted interactions between exposed functional groups, which involve conformational changes of alpha-helix, beta-sheet and aperiodic structure. Here evidence is provided that the loosening of the human serum protein structure takes place primarily in various concentrations of urea before and after beer consumption (BC). Differences in the fluorescence behavior of the proteins are attributed to disruption of the structure of proteins by denaturants as well as by the change in their compactability as a result of ethanol consumption. In summary, thermal denaturation parameters, fluorescence, So and the content of secondary structure have shown that HSG is more stable fraction than HSA.

Beer consumption and changes in stability of human serum proteins.

The aim of this study was to evaluate the influence of beer consumption (BC) on the functional and structural properties of human serum proteins (HSP). Thirty-eight volunteers (after coronary bypass) were divided into two groups: experimental (EG) and control (CG). Nineteen volunteers of the EG consumed 330 mL per day of beer (about 20 g of alcohol) for 30 consecutive days. The CG volunteers consumed mineral water instead of beer. Blood samples were collected from EG and CG patients before and after the experiment. Albumin (Alb), globulin (Glo), and methanol-precipitable proteins (MPP) from human serum were denatured with 8 M urea. Fluorescence and electrophoresis were employed in order to elucidate urea-induced conformational changes and structural behavior of proteins. The measured fluorescence emission spectra were used to estimate the stability of native and denatured protein fractions before and after BC. It was found that before BC the fractions most stable to urea denaturation were Glo, Alb, and MPP fractions. After BC in most of the beer-consuming patients (EG) some changes in native and denatured protein fractions were detected: a tendency to lower stability and minor structural deviations. These qualitative changes were more profound in MPP than in Alb and Glo. Thus, Glo is more resistible to alcohol influence than Alb, which in turn is more resistible than MPP. No serum protein changes were detected in patients of CG.

Biotransformation of constituents of essential oils by germinating wheat seed.

Wheat seeds, when exposed to essential oils, are able to metabolise certain monoterpenes. The actual amounts of the compounds and their derivatives in the endosperm and embryo of wheat seeds, after exposure to the monoterpenes were determined. Neral and geranial, which are the constituents of citral, are reduced and oxidised to the corresponding alcohols and acids. Similarly citronellal, pulegone and carvacrol are converted partly to the corresponding reduction and oxidation products. The aromatic compound vanillin is partly reduced to vanillyl alcohol or oxidised to vanillic acid. In all cases it seems that part of the compounds applied are degraded, as indicated by the inability to account for all the compounds, which were supplied to the germinated seeds. In most cases the derivatives of the essential oil applied were less toxic than the parent compound. The possible role of non-specific enzymes by which the compounds are oxidised or reduced is discussed.

Redetermination of [Ni(NH(3))(6)]Cl(2) at 173 K.

The structure of hexaamminenickel(II) dichloride determined previously by Essmann et al. [Essmann, Kreiner, Niemann, Rechenbach, Schmieding, Sichla, Zachwieja & Jacobs (1996). Z. Anorg. Allg. Chem. 622, 1161-1166] was redetermined at 173 K. There are no significant differences between these two structures.

Intrinsic tryptophan fluorescence of human serum proteins and related conformational changes.

The unfolding of human serum proteins (HSP) was studied by measuring the intrinsic fluorescence intensity at a wavelength of excitation corresponding to tryptophan's or typosine's fluorescence and surface hydrophobicity. The maxima emission wavelengths (lambdamax) of human serum albumin (HSA) and human serum globulin (HSG) before beer consumption (BC) were 336.0 and 337.0 nm and after BC shifted to 335.0 and 334.0 nm, respectively. The surface hydrophobicity slightly increased after BC. In a solution of 8 M urea the lambdamax of BSA shifted to 346.4 and that of BSG to 342.5 nm. In contrast, in the same solution but after BC the lambdamax positions of HSA and HSG shifted to 355.9 and 357.7 nm, respectively. A decrease in fluorescence intensity, a shift in the maximum of emission, and an increase in surface hydrophobicity which reflected unfolding of proteins were observed. Here we provide evidence that the loosening of the HSP structure takes place primarily in various concentrations of urea before and after beer consumption. Differences in the fluorescence behavior of the proteins are attributed to disruption of the structure of proteins by denaturants as well as by the change in their compactability as a result of ethanol consumption.

Phase II evaluation of treatment of complete resection of hepatic metastases from colorectal cancer and adjuvant hepatic arterial infusion of floxuridine: an Eastern Cooperative Oncology Group Study (PB083).

This study was designed to evaluate hepatic arterial infusion of floxuridine (FUDR) in patients with resected hepatic metastases from colorectal cancer. Patients who met eligibility criteria had an Infusaid pump (Infusaid Corporation, Sharon, MA, U.S.A.) implanted for intraarterial administration of chemotherapy. After complete surgical resection of hepatic metastases, FUDR (0.2 mg/kg/day) was given in 28-day cycles consisting of 14 days of treatment followed by 14 days of rest. Of 11 patients enrolled, one was ineligible, one received no treatment because of a blocked pump, and nine were treated per protocol. Of the nine treated patients, all are dead: one from hepatic toxicity, one from unrelated causes, and seven from progressive disease. Grade 3-4 toxicity included three cases of gastritis and two cases of hepatotoxicity from FUDR. Although this regimen was not successful, in part because of toxicity, the patient population studied here should be considered for future studies of adjuvant therapy.

Hexasupersilyl-triprismo-hexastannane (tBu3 Si)6 Sn6 -The First Molecular Tin Compound Containing a Sn6 Prism.

Dark violet hexastannane (tBu3 Si)6 Sn6 displays a new framework motif for molecular tin compounds, in which six Sn atoms are located at the corners of a trigonal prism. The compound can be synthesized according to Equation (a). R*=SitBu3 .

Barren Rorschachs: a conceptual approach.

A discussion is presented of five Rorschach protocols that appear to meet the criteria proposed by Exner and Weiner (1982, p. 31) for "brief and barren" Rorschach protocols. The protocols were obtained from a social service agency treating abused, neglected, disturbed, and delinquent youths. An attempt is made to bring to bear a conceptual approach to these Rorschachs, so that they may be seen as clinically valuable and revealing, hence not "invalid" diagnostic protocols. Emphasis is placed on the subjects' approach to the task, the subject-examiner interaction, and the meaning of the subjects' ostensibly peripheral comments. Recommendations are offered regarding ways to maximize the clinical utility of such protocols.