1-[(4-Chlorobenzoyl)methyl]-4-(N,N-dimethylamino)pyridinium bromide sesquihydrate and 1-[(4-bromobenzoyl)methyl]-4-(N,N-dimethylamino)pyridinium bromide sesquihydrate

The title compounds, C15H16ClN2O+.Br-.1.5H2O and C15H16BrN2O+.Br-.1.5H2O, are isomorphous. The benzene ring is oriented nearly normal to the pyridine ring in both compounds. The molecular packing is mainly influenced by intermolecular O-H...O and O-H...Br interactions, as well as weak intramolecular C-H...O interactions. The H2OBr- units form an extended water-bromide chain, with a bridging water molecule on a twofold axis.

Intensive care management of acute liver failure

Acute liver failure represents one of the most challenging conditions in intensive care treatment. In most cases there is no causal medical therapy available for survive making the intensive care treatment as the most important management tool, as bridge to transplant or still the recovery of the liver! These patients frequently develop multi-organ failure, placing them at risk of hemodynamic disorder, cerebral edema, coagulopathy and various renal and metabolic complications.

Determination of the dynamics of restored teeth by 3D electronic speckle pattern interferometry

BACKGROUND AND OBJECTIVES

The difficulties typically encountered in studying the effects of restorations on tooth reinforcement are often due to the 3-dimensional (3D) nature of deformation. Therefore, electronic 3D-Speckle-Interferometry (3D-ESPI) was used to assess the impact of different restorative materials on the deformation of teeth.

STUDY DESIGN/MATERIALS AND METHODS

Small and large MOD-preparations in extracted premolars were restored with gold inlays, ceramic inlays, composite resin inlays, amalgam, or composite resin. The restorations and cusps were loaded (90 N) and the deformation was assessed by 3D-ESPI.

RESULTS

Teeth with small restorations were deformed only slightly and the differences between the materials were minimal (P>0.05). In contrast, teeth with large restorations displayed material-specific deformation patterns: (a) all materials led to decreased deformation as compared with unfilled teeth, (b) elastic materials caused only local deformation, (c) non-adhesive materials resulted in translation of the restoration and marginal discrepancies, (d) adhesive inlays brought about increased deformation of the luting resin composite, (e) loading of the cusps caused higher deformation than loading of the restorations, and (f) bonded restorations stabilized the cusps.

CONCLUSIONS

The results show that the deformation pattern of restored teeth is material-specific but the extent of deformation is primarily limited by the remaining tooth substance.

Mesohepatektomie

Mesohepatectomy was performed in seven patients with a primary or secondary central liver tumor. We describe the surgical procedure for mesohepatectomy (removal of segments IVa/IVb/V/VIII +/- I) in the treatment of central hepatic tumors. This technically demanding but safe approach requires careful vascular dissection to maintain blood supply and venous drainage of the two remaining liver parts. Mesohepatectomy results in one or two large resection planes bearing a considerable risk of parenchymal necrosis or biliary leakage. Its major advantage over extended hepatectomy is the preservation of functioning liver tissue. Thus, the risk of postoperative liver failure is reduced and, in case of intrahepatic recurrence, the chance for repeat hepatectomy improved. Mesohepatectomy should be considered in selected cases of central liver tumors in which extended resection would be associated with a high risk of liver insufficiency.

Terlipressin and gelafundin: safe therapy of hepatorenal syndrome

BACKGROUND AND AIM

Hepatorenal syndrome (HRS) occurs in about 20 % of patients with liver cirrhosis and ascites and is characterized by intensive renal vasoconstriction, low glomerular filtration rate but preserved tubular function and normal renal histology. The potential of terlipressin and albumin to reverse HRS after a time period of 14 days has already been shown. However, intravenous albumin is expensive (approximately 25 per 50 ml 20% albumin in Germany) and has limited availability in some settings. Therefore we used an artificial plasma substitute, Gelatinepolysuccinat, which is less expensive (approximately 12 per 500 ml). The aim of our present study was to examine the effects of terlipressin and Gelatinepolysuccinat on renal function and hemodynamics in a time period of six days.

METHODS AND PATIENTS

Seven consecutive patients with cirrhosis and hepatorenal syndrome were included in a pilot study of terlipressin (6 mg /24 h iv) therapy associated with i.v. Gelatinepolysuccinat (Gelafundin 4% Infusionslösung, Company Braun, Mw: 30 000 D).

RESULTS

In five of the seven patients treatment was associated with a marked reduction of serum creatinine after six days (3.85 +/- 0.44 mg/dl vs.1.9 +/- 0.32 mg/dl; p< 0.018). Creatinine clearance improved (20 +/- 8.8 ml/min vs. 43 +/- 11.7 ml/min; p<0.12). There was a remarkable improvement in circulatory function in all patients, with an increase in mean arterial pressure (58+/-4.4 mmHg vs. 75 +/- 4.5 mmHg, p< 0.001). No patient developed signs of intestinal, myocardial or distal ischemia.

CONCLUSIONS

Terlipressin and Gelatinepolysuccinat appear to be a safe and effective treatment of hepatorenal syndrome.

Postoperative ICU management in liver transplant patients

The unique pathophysiology of end-stage liver disease (ESLD) has important implications on critical care treatment after liver transplantation. To determine hemodynamic parameters and responses, each patient must be carefully evaluated for the individual clinical appearance of cirrhosis and portal hypertension. Although data are limited, recent progress in the treatment of ESLD and its complications, such as hepatorenal syndrome (HRS), portopulmonary hypertension (PPH), and hepatopulmonary syndrome (HPS) is evident. The improved understanding of the pathophysiology of ESLD has resulted in novel treatments and approaches to the problems that emerge as patients get critically ill or undergo orthotopic liver transplantation (OLT). These issues become much more relevant with increased adult-to-adult living donor liver transplantation, where the scheduled operation allows a precise preoperative management in an Intensive Care Unit (ICU).

Increment technique for extended Class V restorations: an experimental study

The application and polymerization of composite or polyacid-modified resin composites in thin layers (increment technique) for filling cavities might partially compensate for the stress associated with polymerization shrinkage. In this study, the effect of this technique on the marginal integrity of Class V polyacid-modified composite restorations was investigated. In 30 extracted premolars, extended Class V cavities were prepared with the apical margin in root dentin and the coronal margin in enamel. They were then subjected to different treatments (10 teeth in each case): a) placement and polymerization of a thin resin composite layer (Dyract-Dyract PSA) in the coronal part of the cavity (plus one increment for the residual part) (Group 1), b) a thin layer at the apical part of the cavity (plus one increment for the residual part) (Group 2) and c) restoration of the entire cavity with one increment (bulk technique) (Group 3). Following three days' storage in water, the teeth were subjected to cyclic thermal loading (4 degrees C <-> 55 degrees C, 2,000 cycles). The percentages of defective bonding detected along the total length of the restoration margin were assessed before and after thermocycling by scanning electron microscopy. Following loading and thermocycling, no significant differences were found at the restoration-enamel interface. Fewer gaps were found at the restoration-dentin interface in Group 1 (18.7 +/- 25.7%) and Group 2 (20.5 +/- 22.8%) compared to the reference Group 3 (42.2 +/- 30.6%) (Mann-Whitney U test: p<0.05). Moreover, there were no significant differences between the two increment groups (1 and 2). In a significantly larger number of cases, a completely intact dentin restoration margin was detected when a coronal increment (Group 1) (44.4%) was used instead of the bulk technique (Group 3) (13.6%) (Chi square test: p<0.05). These results indicate that gap formation can be significantly minimized by using an increment technique to restore extended Class V cavities with polyacid-modified composite materials.

Effects of chronic furosemide treatment and age on cell division in the adult gerbil inner ear

Atrophy of the stria vascularis and spiral ligament and an associated decrease in the endocochlear potential (EP) are significant factors in age-related hearing loss (presbyacusis). To model this EP decrease, furosemide was delivered into the round-window niche of young adult gerbils by osmotic pump for seven days, chronically reducing the EP by 30-40 mV. Compound action potential (CAP) thresholds were correspondingly reduced by 30-40 dB SPL at high frequencies. Two weeks after withdrawal of furosemide, the treated ears showed an EP recovery of up to 20-30 mV along with a similar recovery of CAP thresholds. The influence of cell division on furosemide-induced and age-related decline of the EP was examined using a mitotic tracer, bromodeoxyuridine (BrdU). Cell proliferation was examined in three groups: young control, furosemide-treated, and aged cochleas. Sections immunostained for BrdU were bleached with H2O2 to eliminate ambiguities with melanin pigment in the inner ear. Cell types positively labeled for BrdU in all three groups included Schwann cells in Rosenthal's canal; glial cells in the osseous spiral lamina; fibrocytes in the limbus, sacculus, and spiral ligament (SL); epithelial cells in Reissner's and round-window membranes; intermediate cells in the stria vascularis; and vascular endothelial cells. Quantitative analysis showed that the mean number of BrdU-positive (BrdU+) intermediate cells in the stria did not differ significantly among the three groups. In contrast, there was a significant increase of BrdU + fibrocytes in the SL of furosemide-treated animals as compared to the young control group. Moreover, there was a significant decrease in labeled fibrocytes in the aged versus the young ears, particularly among the type II and type IV subtypes. The results suggest that the increased fibrocyte turnover in the SL after furosemide treatment may be related to the recovery of EP and CAP thresholds, supporting the hypothesis that fibrocyte proliferation may be essential for maintaining the EP and cochlear function in normal and damaged cochleas. Moreover, the decreased turnover of SL fibrocytes with age may be a contributing factor underlying the lateral wall pathology and consequent EP loss that often accompanies presbyacusis.

[Extended indications for liver transplantation in HCC with special reference to living donor liver donation]

Under strict indication criteria (solitary tumor < 5 cm or up to 3 tumors < 3 cm, no vascular invasion) the 5-year-survival rate after liver transplantation for HCC in cirrhosis is up to 70% to 75% in comparison to 80% to 90% in benign disease. With regard to organ shortage an extended indication for liver transplantation in HCC, i.e. for highly differentiated HCC between 5 cm and 7 cm, can only be discussed if there is an increase in the number of donor livers. Currently, living donation offers the only solution for this problem. The decision for living donor liver transplantation for an extended indication has to be drawn most carefully and individually. In addition to the donor's risk, to the prognosis of the recipient and to economical aspects the desire of the donor to offer the chance of transplantation despite a probably poor prognosis has to be considered and respected.

An in vitro comparison of metal and transparent matrices used for bonded class II resin composite restorations

This study compared excess formation of direct bonded Class II restorations using different matrix systems-metal or transparent. Sixty freshly extracted, non-carious, posterior human teeth were used. In all of the teeth, standardized MOD-cavities were prepared with the gingivoproximal margins located 1.0-1.5 mm cervical to the cemento-enamel junction. The prepared teeth were randomly assigned to six groups. Half were restored using metal matrices and wooden wedges; the other half were restored using transparent matrices and reflective wedges. Three different material systems were used to fill the cavities: 1) a hybrid composite (Tetric) plus an adhesive bonding agent (Syntac Classic), 2) a flowable composite (Tetric Flow) plus Syntac Classic and 3) a compomer (Dyract AP) together with an adhesive bonding agent designed for compomers (Prime & Bond NT). After the specimens were preserved in saline solution, scanning electron microscopy (SEM) assessed the amount of overhang formation at the restoration margins. The data collected indicated the use of transparent matrices resulted in significantly higher amounts of excess material at the restoration margins compared with metal matrices. Moreover, there was no significant difference between the materials when the same matrix was used. All of the dental restorations examined displayed material overhang. Based on these findings, the authors concluded that the type of matrix exerts a major impact on overhang formation, with metal matrices resulting in significantly less excess material buildup.

Human MHC class I transgenic mice deficient for H2 class I expression facilitate identification and characterization of new HLA class I-restricted viral T cell epitopes

Although mice transgenic (Tg) for human MHC (HLA) class I alleles could provide an important model for characterizing HLA-restricted viral and tumor Ag CTL epitopes, the extent to which Tg mouse T cells become HLA restricted in the presence of endogenous H2 class I and recognize the same peptides as in HLA allele-matched humans is not clear. We previously described Tg mice carrying the HLA-B27, HLA-B7, or HLA-A2 alleles expressed as fully native (HLA(nat)) (with human beta(2)-microglobulin) and as hybrid human/mouse (HLA(hyb)) molecules on the H2(b) background. To eliminate the influence of H2(b) class I, each HLA Tg strain was bred with a H2-K(b)/H2-D(b)-double knockout (DKO) strain to generate mice in which the only classical class I expression was the human molecule. Expression of each HLA(hyb) molecule and HLA-B27(nat)/human beta(2)-microglobulin led to peripheral CD8(+) T cell levels comparable with that for mice expressing a single H2-K(b) or H2-D(b) gene. Influenza A infection of Tg HLA-B27(hyb)/DKO generated a strong CD8(+) T cell response directed at the same peptide (flu nucleoprotein NP383-391) recognized by CTLs from flu-infected B27(+) humans. As HLA-B7/flu epitopes were not known from human studies, we used flu-infected Tg HLA-B7(hyb)/DKO mice to examine the CTL response to candidate peptides identified based on the B7 binding motif. We have identified flu NP418-426 as a major HLA-B7-restricted flu CTL epitope. In summary, the HLA class I Tg/H2-K/H2-D DKO mouse model described in this study provides a sensitive and specific approach for identifying and characterizing HLA-restricted CTL epitopes for a variety of human disease-associated Ags.