bluuebunny/crossref_metadata_2025 huggingface dataset:
Thixotrophy property of hydrogels to evaluate the cell growing on the inside of the material bulk (Amber effect)
Authors: Barbucci Rolando , Leone Gemma , Lamponi Stefania
Published: October 2005

The realization of injectable hydrogels is one of the most challenging aims of biomedical research. Most injectable hydrogels are obtained by photopolymerization in situ. A hydrogel which is able to pass through a needle without losing its structure once crosslinked would be of great interest for several biomedical applications. In this work, hyaluronane and alginate–based 50% hydrogels were synthesized, their thixotrophic behavior was verified and their mechanical properties (G′ and G″) were determined before and after the passage through the needle. A morphological analysis by scanning electron microscopy (SEM) was also performed in order to evaluate the effect of the passage of the hydrogel through the needle on the morphological structure of the material. The thixotrophic property of these hydrogels is used to realize a cell‐containing material that supports cell proliferation and growth permitting in vivo engineering of new tissues. In fact, thixotrophic hydrogel can be sucked together with cell suspension and in this way cells remain entrapped inside the hydrogel structure (Amber effect). A comparison of the cell growth using this technique with the classical seeding technique (cell seeding onto the hydrogel) was performed. A different behavior was found between hyaluronane and alginate–based hydrogels. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Influence of powder particle size distribution on complex viscosity and other properties of acrylic bone cement for vertebroplasty and kyphoplasty
Authors: Hernández Lidia , Gurruchaga Mariló , Goñi Isabel
Published: October 2005

For use in vertebroplasty and kyphoplasty, an acrylic bone cement should possess many characteristics, such as high radiopacity, low and constant viscosity during its application, low value of the maximum temperature reached during the polymerization process (Tmax), a setting time (tset) that is neither too low nor too high, and high compressive strength. The objective of this study was to investigate the influence of the powder particle distribution on various properties of one acrylic bone cement; namely, residual monomer content, Tmax, tset, complex viscosity, storage and loss moduli, injectability, and quasi‐static compressive strength and modulus. It was found that the formulations that possessed the most suitable complex viscosity‐versus‐mixing time characteristics are those in which the ratio of the large poly(methyl methacrylate) beads (of mean diameter 118.4 μm) to the small ones (of mean diameter 69.7 μm) was at least 90% w/w. For these formulations, the values of the other properties determined were acceptable. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Degenerate PCR method for identification of an antiapoptotic gene in BHV‐1
Authors: Marfè G. , De Martino L. , Filomeni G. , Di Stefano C. , Giganti M.G. , Pagnini U. , Napolitano F. , Iovane G. , Ciriolo M.R. , Salimei P. Sinibaldi
Published: October 2005

To investigate on the hypothetical presence of an antiapoptotic gene, we utilized the CODEHOP (COnsensus‐DEgenerate Hybrid Oligonucleotide Primers) strategy amplifying unknown sequences from a background of genomic (bovine herpesvirus type‐1) BHV‐1 DNA. An alignment of carboxyl‐terminal domains belonging to three proteins encoded by γ34.5, MyD116 and GADD34 genes, was carried out to design degenerate PCR primers in highly conserved regions. This allowed the amplification of a 110 bp fragment. This fragment was subjected to automatic sequencing and DNA sequence analysis revealed that its position resided between the nt 14363 and the nt 14438 in bovine herpesvirus type‐1 (BHV‐1) Cooper strain sharing an identity of 86% (UL14). Transient transfections showed that UL14 protein is efficient in protecting MDBK and K562 cells from sorbitol induced apoptosis. The protein's anti‐apoptotic function may derive from its heat shock protein‐like properties. J. Cell. Biochem. 97: 813–823, 2006. © 2005 Wiley‐Liss, Inc.
Dynamic lipidomics of the nucleus
Authors: Hunt Alan N.
Published: October 2005

Once nuclear envelope membranes have been removed from isolated nuclei, around 6% of mammalian cell phospholipid is retained within the nuclear matrix, which calculations suggest may occupy 10% of the volume of this subcellular compartment. It is now acknowledged that endonuclear phospholipid, largely ignored for the past 40 years, provides substrate for lipid‐mediated signaling events. However, given its abundance, it likely also has other as yet incompletely defined roles. Endonuclear phosphatidylcholine is the predominant phospholipid comprising distinct and highly saturated molecular species compared with that of the whole cell. Moreover, this unusual composition is subject to tight homeostatic maintenance even under conditions of extreme dietary manipulation, presumably reflecting a functional requirement for highly saturated endonuclear phosphatidylcholine. Recent application of new lipidomic technologies exploiting tandem electrospray ionization mass spectrometry in conjunction with deuterium stable isotope labeling have permitted us to probe not just molecular species compositions but endonuclear phospholipid acquisition and turnover with unparalleled sensitivity and specificity. What emerges is a picture of a dynamic pool of endonuclear phospholipid subject to autonomous regulation with respect to bulk cellular phospholipid metabolism. Compartmental biosynthesis de novo of endonuclear phosphatidylcholine contrasts with import of phosphatidylinositol synthesized elsewhere. However, irrespective of the precise temporal–spatial–dynamic relationships underpinning phospholipid acquisition, derangement of endonuclear lipid‐mediated signaling from these parental phospholipids halts cell growth and division indicating a pivotal control point. This in turn defines the manipulation of compartmentalized endonuclear phospholipid acquisition and metabolism as intriguing potential targets for the development of future antiproliferative strategies. J. Cell. Biochem. © 2005 Wiley‐Liss, Inc.
Organization of the coelomic lining and a juxtaposed nerve plexus in the suckered tube feet of Parastichopus californicus (Echinodermata: Holothuroida)
Authors: Cavey Michael J.
Published: October 2005

The coelomic lining of the water‐vascular canal in a suckered tube foot from the sea cucumber, Parastichopus californicus, is a pseudostratified myoepithelium consisting of flagellated adluminal cells and myofilament‐bearing retractor cells. The bodies of adluminal cells flank the water‐vascular canal and send basal processes between the underlying retractor cells to confront the podial connective tissue. Retractor cells have a contractile apparatus of unregistered thick and thin myofilaments. The contractile apparatus is confined to the medullary sarcoplasm and oriented parallel to the primary axis of a tube foot. The bodies and processes of retractor cells intermingle with the basal processes of adluminal cells at the basal lamina of the coelomic lining. A ganglionated nerve plexus in the podial connective tissue approximates the basal lamina. Neuronal connectives link the ganglia to one another and to the nerve plexus in deep sectors of the podial epidermis. External laminae enveloping the ganglia and connectives in the podial connective tissue are continuous with the basal lamina of the epidermis. The adventitial nerve plexus, since it merges with the epidermal nerve plexus, is a component of the ectoneural division of the echinoderm nervous system. J. Morphol. © 2005 Wiley‐Liss, Inc.
Binucleate trophoblast giant cells in the water buffalo (Bubalus bubalis) placenta
Authors: Carvalho A.F. , Klisch K. , Miglino M.A. , Pereira F.T.V. , Bevilacqua E.
Published: October 2005

The binucleate trophoblast giant cells (BNC) of the water buffalo, Bubalus bubalis, placenta were studied, with emphasis on the synthesis of BNC‐specific proteins. Placentomal tissues of 27 water buffalos (2–10 months of pregnancy) were processed for light and electron microscopy. The frequency of BNCs was 20% of the trophoblastic cells in 2–3‐month placentas and increased to 27% in the later stages. Ultrastructurally, binucleate cells displayed a prominent granular endoplasmic reticulum and Golgi apparatus, typical of cells involved with protein synthesis and exportation. The buffalo BNCs contained periodic acid‐Schiff (PAS)‐positive granules and reacted with antisera against bovine placental lactogen, prolactin‐related protein‐I, and pregnancy‐associated glycoproteins. Lectin histochemistry with Dolichos biflorus agglutinin, Vicia villosa agglutinin, and Phaseolus vulgaris leucoagglutinin showed specific staining of BNCs. Different stages of BNC migration and fusion with uterine epithelial cells were observed. Trinucleate feto‐maternal hybrid cells were the typical outcome of cell fusions. These cells underwent degeneration, with typical morphological features of apoptosis. The results revealed a strong homology between water buffalo and cattle BNCs concerning cell morphology, protein expression, glycosylation pattern, and characteristics of cell migration and fusion. J. Morphol. © 2005 Wiley‐Liss, Inc.
Effect of Er:YAG laser on enamel acid resistance: Morphlogical and atomic spectrometry analysis
Authors: Cecchini Renata Cristina M. , Zezell Denise Maria , de Oliveira Elisabeth , de Freitas Patricia M. , Eduardo Carlos de P.
Published: October 2005

Background and Objectives

This study evaluated the effect of Er:YAG laser on enamel acid resistance.

Study Design/Materials and Methods

Seventy human enamel slabs were randomly divided into seven groups (n = 10): G1, Er:YAG laser (Key Laser 2, KaVo, Germany) 60 mJ, 2 Hz, 33.3 J/cm2 (handpiece no. 2051, non‐contact); G2, Er:YAG laser 80 mJ, 2 Hz, 44.4 J/cm2 (handpiece no. 2051, non‐contact); G3, Er:YAG laser 120 mJ, 2 Hz, 66.6 J/cm2 (handpiece no. 2051, non‐contact); G4, Er:YAG laser 64 mJ, 2 Hz, 20 J/cm2 (handpiece no. 2055, contact); G5, Er:YAG laser 86.4 mJ, 2 Hz, 26.9 J/cm2 (handpiece no. 2055, contact); G6, Er:YAG laser 135 mJ, 2 Hz, 42.2 J/cm2 (handpiece no. 2055, contact); G7, control. After laser irradiation, samples were submitted to an acid challenge. For both the nos. 2051 and 2055 handpieces, irradiation was performed with a water cooled spray (5.0 ml/minutes). The calcium and phosphorous ions delivered from the tooth surface were quantified by atomic emission spectrometry, and morphological analysis of the enamel surface was performed under scanning electron microscopy. Kruskal–Wallis and multiple comparisons tests were applied to distinguish significant differences among the treatments (α = 5%).

Results

Groups G1, G2, and G4 presented decreased demineralization. The SEM evaluation revealed different surface alterations as a result of the different energies used.

Conclusion

Lower energies can decrease enamel solubility without severe alterations of the enamel. Lasers Surg. Med. 00:1–7,2005. © 2005 Wiley‐Liss, Inc.
Autofluorescence characterization for the early diagnosis of neoplastic changes in DMBA/TPA‐induced mouse skin carcinogenesis
Authors: Diagaradjane Parmeswaran , Yaseen Mohammad A. , Yu Jie , Wong Michael S. , Anvari Bahman
Published: October 2005

Background and Objective

Squamous cell carcinoma (SCC), the second most common skin cancer, usually remains confined to the epidermis for some time but eventually penetrates the underlying tissues, if left untreated. The non‐invasive early detection of the SCC is important for appropriate therapeutic strategies. In this study, we aim to characterize the tissue transformation in DMBA/TPA induced mouse skin tumor model using autofluorescence excitation emission matrix (EEM) in conjunction with a multivariate statistical method for early detection of the neoplastic changes.

Study Design/Materials and Methods

The fluorescence EEM from experimental group (n = 40; DMBA/TPA application), control group (n = 6; acetone application), and the blank group (n = 6; no application of DMBA/TPA or acetone) were measured every week using a spectrofluorometer coupled with a fiber optic bundle. The EEM was recorded at excitation wavelengths from 280 to 460 nm at 10 nm intervals and the fluorescence emission was scanned from 300 to 750 nm. The fluorescence emission characteristics corresponding to different fluorophores were extracted from the EEM and the spectral data were used in a multiple/linear discriminant statistical algorithm.

Results

The changes in the fluorescence emission intensity were observed as early as the 1st week of tumor initiation by DMBA. Morphological changes as well as differences in the gross appearance of the skin surface were observed during the entire tumor initiation and promotion period of 15 weeks. The statistical analysis was performed for each excitation wavelength in the EEM and better classification accuracy was obtained for 280 and 410 nm excitations, corresponding to tryptophan and endogenous porphyrins, respectively. The statistical analysis of the combination wavelengths resulted in 11.6% increase in the overall classification accuracy when compared to the highest classification accuracy obtained with single wavelength analysis.

Conclusion

The intensity ratio mapping using the combination of emission intensities of key fluorophores such as tryptophan, collagen, NADH, and endogenous porphyrins from the measured EEM in conjunction with a simple multivariate statistical analysis can be used as a potential tool for the discrimination of early neoplastic changes with improved classification accuracy. Tryptophan and endogenous porphyrins may be used as biomarkers for the discrimination of early neoplastic changes when single wavelength excitations are used. Lasers Surg. Med. 00:1–14,2005. © 2005 Wiley‐Liss, Inc.
Effects of monopolar radiofrequency treatment over soft‐tissue fillers in an animal model: Part 1
Authors: England Laura J. , Tan Mei‐Heng , Shumaker Peter R. , Egbert Barbara M. , Pittelko Kim , Orentreich David , Pope Karl
Published: October 2005

Background and Objectives

Monopolar radiofrequency (RF) treatment is used by physicians to tighten and contour the skin of their patients. In many cases, patients have received prior treatment with other aesthetic modalities such as soft‐tissue augmentation or they may wish to receive these treatment modalities simultaneously. Together, soft‐tissue augmentation and monopolar RF treatment have the potential to restore tissue volume and improve facial laxity. To date, no published studies have documented the effects of RF treatment directly over soft‐tissue fillers.

Study Design/Materials and Methods

We examined the tissue interactions of monopolar RF heating with five commonly injected fillers in a juvenile pig model. This is the first part of a two‐part study. In this study, the interaction of monopolar RF and filler substances was examined over a period of 4 months. The five soft‐tissue fillers examined were cross‐linked human collagen (Cosmoplast™), hyaluronic acid (Restylane®), calcium hydroxylapatite (Radiesse™), polylactic acid (Sculptra™), and liquid injectable silicone (Silikon™ 1000).

Results

There was no apparent increase in the risk of local burns and no observable effect of RF treatment on filler persistence in the tissue. With monopolar RF treatment, an increase in fibroplasia and collagen deposition surrounding Restylane, Radiesse, and Sculptra was observed. When scored in a blinded fashion, the increase in collagen deposition was statistically significant for Radiesse.

Conclusions

In this animal study, RF treatment had no observed adverse effect on filler collagen responses or persistence. Filler presence did not increase the risk of undesirable thermal effects with monopolar RF treatment. Further clinical studies are required to evaluate the effect of monopolar RF treatment over dermal fillers with respect to aesthetic outcome. Lasers Surg. Med. 00:1–10,2005. © 2005 Wiley‐Liss, Inc.
Cerebral hemodynamic and metabolic profiles in fulminant hepatic failure: Relationship to outcome
Authors: Aggarwal Shushma , Obrist Walter , Yonas Howard , Kramer David , Kang Yoogoo , Scott Victor , Planinsic Raymond
Published: October 2005

The purpose of this retrospective study was to examine the potential role of cerebral hemodynamic and metabolic factors in the outcome of patients with fulminant hepatic failure (FHF). Based on the literature, a hypothetical model was proposed in which physiologic changes progress sequentially in five phases, as defined by intracranial pressure (ICP) and cerebral blood flow (CBF) measurements. Seventy-six cerebral physiologic profiles were obtained in 26 patients (2 to 5 studies each) within 6 days of FHF diagnosis. ICP was continuously measured by an extradural fiber optic monitor. Global CBF estimates were obtained by xenon clearance techniques. Jugular venous and peripheral artery catheters permitted calculation of cerebral arteriovenous oxygen differences (AVDO2), from which cerebral metabolic rate for oxygen (CMRO2) was derived. A depressed CMRO2 was found in all patients. There was no evidence of cerebral ischemia as indicated by elevated AVDO2s. Instead, over 65% of the patients revealed cerebral hyperemia. Eight of the 26 patients underwent orthotopic liver transplantation—all recovered neurologically, including 6 with elevated ICPs. Of the 18 patients receiving medical treatment only, all 7 with increased ICP died in contrast to 9 survivors whose ICP remained normal (

P

< 0.004). Hyperemia, per se, was not related to outcome, although it occurred more frequently at the time of ICP elevations. Six patients were studied during brain death. All 6 revealed malignant intracranial hypertension, preceded by hyperemia. In conclusion, the above findings are consistent with the hypothetical model proposed. Prospective longitudinal studies are recommended to determine the precise evolution of the pathophysiologic changes. (Liver Transpl 2005;11:1353–1360.)
Mesogonadal shunts for extrahepatic portal vein thrombosis and variceal hemorrhage
Authors: Kim Heung Bae , Pomposelli James J. , Lillehei Craig W. , Jenkins Roger L. , Jonas Maureen M. , Krawczuk Laura E. , Fishman Steven J.
Published: October 2005

Extrahepatic portal vein thrombosis (EHPVT) may occur in children or adults and usually comes to clinical attention due to complications of portal hypertension such as variceal hemorrhage. A variety of standard surgical techniques exist to manage these patients, but when these fail surgical options are limited. We describe two novel portosystemic shunts that utilize the gonadal vein as an autologous conduit. Four patients were evaluated for EHPVT with variceal bleeding. None of the patients were candidates for a standard splenorenal shunt due to prior surgical procedures. The first patient underwent a left mesogonadal shunt and the remaining 3 patients underwent a right mesogonadal shunt. Postoperative ultrasound or computed tomography (CT) scan confirmed early patency of the shunt in each patient. There have been no further episodes of variceal hemorrhage with follow-up of 3.5 years in the child who underwent the left mesogonadal shunt, and 17, 19, and 20 months in the patients who underwent the right mesogonadal shunt. Three of the 4 shunts remain patent. One shunt thrombosis occurred in a patient homozygous for the Factor V Leiden mutation despite anticoagulation with coumadin. This is the first report of the successful use of the gonadal vein as an in situ conduit for constructing a portosystemic shunt. In conclusion, the right and left mesogonadal shunts may be useful as salvage operations for patients with EHPVT who have failed standard surgical shunt procedures. (Liver Transpl 2005;11:1389–1394.)
Neonatal hemochromatosis — medical treatment vs. Transplantation: The king's experience
Authors: Rodrigues Fernanda , Kallas Marcia , Nash Ruth , Cheeseman Paul , D'Antiga Lorenzo , Rela Mohamed , Heaton Nigel D. , Mieli-Vergani Giorgina
Published: October 2005

The aim of our study was to compare the outcome of medical treatment vs. liver transplantation in infants with neonatal hemochromatosis (NH) referred to King's College Hospital from 1990–2002. We conducted a retrospective review of 19 children from 14 families. Fifteen children presented at birth and 4 during the first week of life. One child was diagnosed by cordocentesis at 30 weeks of gestation. NH recurred in 7 of 9 families with further children. In one family, 2 children from different fathers were affected. All patients had elevated ferritin levels, hypoalbuminemia, and coagulopathy. Liver histology showed parenchymal collapse, diffuse fibrosis, and moderate to severe hepatocyte hemosiderin deposition. Extrahepatic siderosis was demonstrated by magnetic resonance in 2 patients, lip biopsy in 3, and autopsy in 10. Ten patients received a chelation-antioxidant cocktail: 1 survived, 4 died, and 5 required liver transplantation, of whom 2 died. One of the 9 infants who did not receive the cocktail survived with medical support, 3 died, and 5 required transplantation, of whom 3 died. Seven children are alive, 5 after transplantation, at a median follow-up of 5.6 years, with excellent quality of life and no recurrence of the disease. In conclusion, chelation-antioxidant treatment does not appear to modify the prognosis of NH, at least in severe cases. Liver transplantation, with 50% long-term survival, remains the treatment of choice and should be promptly offered to those infants who do not improve with supportive medical treatment. (Liver Transpl 2005;11:1417–1424.)
Improved machine perfusion preservation of the non-heart-beating donor rat liver using polysol: A new machine perfusion preservation solution
Authors: Bessems Maud , Doorschodt Benedict M. , van Marle Jan , Vreeling Heleen , Meijer Alfred J. , van Gulik Thomas M.
Published: October 2005

Waiting lists for transplantation have stimulated interest in the use of non-heart-beating donor (NHBD) organs. Recent studies on organ preservation have shown advantages of machine perfusion (MP) over cold storage (CS). To supply the liver with specific nutrients during MP, the preservation solution Polysol was developed. The aim of our study was to compare CS in University of Wisconsin solution (UW) with MP using UW-gluconate (UW-G) or Polysol in an NHBD model. After 30 minutes of warm ischemia, livers were harvested from rats for preservation by either CS, MP-UW-G, or MP-Polysol. After 24 hours of preservation, livers were reperfused with Krebs-Henseleit buffer (KHB). Perfusate samples were analyzed for liver damage and function. Biopsies were examined by hematoxylin and eosin staining and transmission electron microscopy. Liver damage was highest after CS compared with the MP groups. MP using Polysol compared with UW-G resulted in less aspartate aminotransferase (AST) and alanine aminotransferase (ALT) release. Perfusate flow, bile production, and ammonia clearance were highest after MP-Polysol compared with CS and MP-UW-G. Tissue edema was least after MP-Polysol compared with CS and MP-UW-G. In conclusion, preservation of the NHBD rat liver by hypothermic MP is superior to CS. Furthermore, MP using Polysol results in better-quality liver preservation compared with using UW-G. (Liver Transpl 2005;11:1379–1388.)
Oxygenation during hypothermic rat liver preservation: An in vitro slice study to demonstrate beneficial or toxic oxygenation effects
Authors: 't Hart Nils A. , van der Plaats Arjan , Faber Alexander , Leuvenink Henri G.D. , Olinga Peter , Wiersema-Buist Janneke , Verkerke Gijsbertus J. , Rakhorst Gerhard , Ploeg Rutger J.
Published: October 2005

Hypothermic machine perfusion (HMP) of abdominal organs is shown to be superior compared to cold storage. However, the question remains if oxygenation is required during preservation as oxygen is essential for energy resynthesis but also generates toxic reactive oxygen species (ROS). To determine if oxygenation should be used during HMP, urea-synthesis rate, adenosine triphosphate (ATP), and generation of ROS were studied in an in vitro model, modeling ischemia-reperfusion injury. Furthermore, expression of uncoupling protein-2 (UCP-2) mRNA was assessed since UCP-2 is a potentially protective protein against ROS. Rat liver slices were preserved for 0, 24, and 48 hr in University of Wisconsin machine perfusion solution (UW-MP) with 0%, 21%, or 95% oxygen at 0–4°C and reperfused for 24 hours. In the 0% and 95% groups, an increase of ROS was found after cold storage in UW-MP. After slice reperfusion, only the 0% oxygen group showed higher levels. The 0% group showed a lower urea-synthesis rate as well as lower ATP levels. mRNA upregulation of UCP-2 was, in contrast to kidney mRNA studies, not observed. In conclusion, oxygenation of UW-MP gave better results. This study also shows that ROS formation occurs during hypothermic preservation and the liver is not protected by UCP-2. We conclude that saturation of UW-MP with 21% oxygen allows optimal preservation results. (Liver Transpl 2005;11:1403–1411.)
Liver transplantation for incidental cholangiocarcinoma: Analysis of the Canadian experience
Authors: Ghali Peter , Marotta Paul J. , Yoshida Eric M. , Bain Vincent G. , Marleau Denis , Peltekian Kevork , Metrakos Peter , Deschênes Marc
Published: October 2005

Cholangiocarcinoma is a biliary tumor, which not infrequently complicates primary sclerosing cholangitis. It carries a poor prognosis and, with the exception of carefully selected individuals in research protocols, contraindicates orthotopic liver transplantation. There has been some suggestion that cholangiocarcinomas incidentally discovered at the time of transplantation carry a better prognosis. The goal of this retrospective study was to perform a national review of outcomes after liver transplantation in Canadian recipients found to have incidental cholangiocarcinoma in their explanted native liver. Six of the seven liver transplant centers in Canada provided clinical and follow-up information on all liver transplant recipients found to have incidental cholangiocarcinoma in their explants. The diagnosis or suspicion of cholangiocarcinoma prior to transplantation were exclusion criteria for this study. Ten individuals with cholangiocarcinoma were transplanted between 1996 and 2003. The median duration of follow-up was 28 months. Eight of the 10 had PSC. All of the tumors were stage I or II. The 3-year survival for these patients was 30%. The median time to recurrence was 26 months (95% confidence interval 13uu-uu37), and the median time to death was 30 months (95% confidence interval 28uu-uu53). In conclusion, although early survival of patients transplanted for incidental cholangiocarcinoma appears good, intermediate- and long-term survival rates are not better than for individuals historically transplanted with known cholangiocarcinoma. Aggressive investigation for cholangiocarcinoma is mandated. Incidentally found tumours remain a difficult treatment problem, and prospective adjuvant chemo-, radio-, and immunotherapies should be investigated. (Liver Transpl 2005;11:1412–1416.)
Pretransplant survival is shorter in HIV-positive than HIV-negative subjects with end-stage liver disease
Authors: Ragni Margaret V. , Eghtesad Bijan , Schlesinger Kimberly W. , Dvorchik Igor , Fung John J.
Published: October 2005

Despite improved survival after liver transplantation (OLTX) in HIV-positive individuals treated with highly active antiretroviral therapy (HAART), some transplant candidates do not survive to OLTX. To determine if pretransplant outcome is related to severity of liver disease and/or HIV infection, we prospectively evaluated 58 consecutive HIV-positive candidates seen at a single center from 1997–2002. Of the 58, 15 (25.9%) were transplanted, whereas 21 (36.2%) died before OLTX, a median one month of evaluation, with more than half of those (12 of 21, 57.1%) dying from infection. By contrast, of 1,359 HIV-negative candidates, 860 (63.3%) were transplanted, whereas 211 (15.5%) died before OLTX (

P

< 0.001). The cumulative survival following initial evaluation was significantly shorter among HIV-positive than HIV-negative candidates (880 vs. 1,427 days,

P

= 0.035, Breslow) but was not related to the initial pretransplant MELD score (16 vs. 15), INR (1.5 vs. 1.5), creatinine (1.3 vs. 1.3 mg/dL), or total bilirubin (6.6 vs. 5.7 mg/dL), respectively, all

P

> 0.05. Among untransplanted HIV-positive candidates, the 21 who died did not differ from the 22 surviving in initial MELD (15 vs. 13), CD4 (230 vs. 327/μL), HIV load (both < 400 copies/mL), HAART intolerance (10/21, 47.6% vs. 10/22, 45.4%), or HCV infection (16/21, 76.2% vs. 16/22, 72.3%), all

P

> 0.05. Further, the 21 did not differ from the 15 transplanted in pre-OLTX CD4, HIV load, or MELD score, all

P

> 0.05. In conclusion, pretransplant survival appears shorter in HIV-positive OLTX candidates and is unrelated to severity of liver or HIV disease. Further study is warranted to determine risk factors for poorer pretransplant outcomes. (Liver Transpl 2005;11:1425–1430)
Immunosuppression for liver transplantation in HCV-infected patients: Mechanism-based principles
Authors: Eghtesad Bijan , Fung John J. , Demetris Anthony J. , Murase Noriko , Ness Roberta , Bass Debra C. , Gray Edward A. , Shakil Obaid , Flynn Bridget , Marcos Amadeo , Starzl Thomas E.
Published: October 2005

We retrospectively analyzed 42 hepatitis C virus (HCV)-infected patients who underwent cadaveric liver transplantation under two strategies of immunosuppression: (1) daily tacrolimus (TAC) throughout and an initial cycle of high-dose prednisone (PRED) with subsequent gradual steroid weaning, or (2) intraoperative antithymocyte globulin (ATG) and daily TAC that was later space weaned. After 36 ± 4 months, patient and graft survival in the first group was 18/19 (94.7%) with no examples of clinically serious HCV recurrence. In the second group, the three-year patient survival was 12/23 (52%), and graft survival was 9/23 (39%); accelerated recurrent hepatitis was the principal cause of the poor results. The data were interpreted in the context of a recently proposed immunologic paradigm that is equally applicable to transplantation and viral immunity. In the framework of this paradigm, the disparate hepatitis outcomes reflected different equilibria reached under the two immunosuppression regimens between the relative kinetics of viral distribution (systemically and in the liver) and the slowly recovering HCV-specific T-cell response. As a corollary, the aims of treatment of the HCV-infected liver recipients should be to predict, monitor, and equilibrate beneficial balances between virus distribution and the absence of an immunopathologic antiviral T-cell response. In this view, favorable equilibria were accomplished in the nonweaned group of patients but not in the weaned group. In conclusion, since the anti-HCV response is unleashed when immunosuppression is weaned, treatment protocols that minimize disease recurrence in HCV-infected allograft recipients must balance the desire to reduce immunosuppression or induce allotolerance with the need to prevent antiviral immunopathology. (Liver Transpl 2005;11:1343–1352.)
Living donor liver transplantation for biliary atresia complicated by situs inversus: Technical highlights
Authors: Matsubara Kentaro , Fujimoto Yasuhiro , Kamei Hideya , Ogawa Kohei , Kasahara Mureo , Ueda Mikiko , Egawa Hiroto , Takada Yasutsugu , Kitajama Masaki , Tanaka Koichi
Published: October 2005

Living-donor liver transplantation (LDLT) has become an established technique to treat children with end-stage liver disease. Biliary atresia (BA), one of the most common indications for liver transplantation in children, can be associated with situs inversus (SI). In the past, the presence of SI has been considered to be an absolute contraindication for liver transplantation because of the technical difficulties. Recently, some reports of successful diseased-donor liver transplantation in patients with BA complicated by SI have been published; however, few reports of that with LDLT exist. The technical difficulties involved with LDLT for such cases have not been described. Herein, we present 4 successful cases of LDLT for BA with SI. Complex anomalies associated with SI, such as a hepatic artery arising from the supraceliac aorta, a preduodenal portal vein, and absence of the retrohepatic inferior vena cava, increase the technical difficulties involved with the operation. Additional caution is required in LDLT because a living-donor graft has short vessels and the availability of vascular grafts from the donor is limited. In conclusion, LDLT for BA complicated by SI can be managed successfully with technical modifications and scrupulous attention. This series represents the largest reported group of patients with BA complicated by SI who underwent a successful LDLT procedure. (Liver Transpl 2005;11:1444–1447.)
Early perioperative death associated with reexpansion pulmonary edema during liver transplantation
Authors: Marujo Wagner C. , Takaoka Flavio , Moura Rita M. A. , Pandullo Fernando L. , Morrone Andre R. , Linhares Marcelo M. , Teruya Alexandre , Altikes Isaac
Published: October 2005

Hydrothorax is a frequent finding in patients with end-stage liver disease. During the hepatectomy phase of liver transplantation, it is often needed to evacuate large pleural effusions. The acute expansion of the collapsed lung can cause reexpansion pulmonary edema with variable clinical significance. However, this complication has rarely been reported after liver transplantation. In conclusion, we report on an overwhelming reexpansion pulmonary edema during a liver transplantation that rapidly led to the patient's demise and speculate if this condition has not been under recognized in the transplantation setting. (Liver Transpl 2005;11:1439–1443.)
Applications of gene targeting technology to mental retardation and developmental disability research
Authors: Pimenta Aurea F. , Levitt Pat
Published: October 2005

The human and mouse genome projects elucidated the sequence and position map of innumerous genes expressed in the central nervous system (CNS), advancing our ability to manipulate these sequences and create models to investigate regulation of gene expression and function. In this article, we reviewed gene targeting methodologies with emphasis on applications to CNS development and neurodevelopmental disorders. © 2005 Wiley‐Liss, Inc. MRDD Research Reviews 2005;11:295–302.
Neurophysiologic evaluation of early cognitive development in high‐risk infants and toddlers
Authors: deRegnier Raye‐Ann
Published: October 2005

New knowledge of the perceptual, discriminative, and memory capabilities of very young infants has opened the door to further evaluation of these abilities in infants who have risk factors for cognitive impairments. A neurophysiologic technique that has been very useful in this regard is the recording of event‐related potentials (ERPs). The event‐related potential (ERP) technique is widely used by cognitive neuroscientists to study cognitive abilities such as discrimination, attention, and memory. This method has many attractive attributes for use in infants and children as it is relatively inexpensive, does not require sedation, has excellent temporal resolution, and can be used to evaluate early cognitive development in preverbal infants with limited behavioral repertories. In healthy infants and children, ERPs have been used to gain a further understanding of early cognitive development and the effect of experience on brain function. Recently, ERPs have been used to elucidate atypical memory development in infants of diabetic mothers, difficulties with perception and discrimination of speech sounds in infants at risk for dyslexia, and multiple areas of cognitive differences in extremely premature infants. Atypical findings seen in high‐risk infants have correlated with later cognitive outcomes, but the sensitivity and specificity of the technique has not been studied, and thus evaluation of individual infants is not possible at this time. With further research, this technique may be very useful in identifying children with cognitive deficits during infancy. Because even young infants can be examined with ERPs, this technique is likely to be helpful in the development of focused early intervention programs used to improve cognitive function in high‐risk infants and toddlers. © 2005 Wiley‐Liss, Inc. MRDD Research Reviews 2005;11:317–324.
Positron emission tomography methods with potential for increased understanding of mental retardation and developmental disabilities
Authors: Sundaram Senthil K. , Chugani Harry T. , Chugani Diane C.
Published: October 2005

Positron emission tomography (PET) is a technique that enables imaging of the distribution of radiolabeled tracers designed to track biochemical and molecular processes in the body after intravenous injection or inhalation. New strategies for the use of radiolabeled tracers hold potential for imaging gene expression in the brain during development and following interventions. In addition, PET may be key in identifying the physiological consequences of gene mutations associated with mental retardation. The development of high spatial resolution microPET scanners for imaging of rodents provides a means for longitudinal study of transgenic mouse models of genetic disorders associated with mental retardation. In this review, we describe PET methodology, illustrate how PET can be used to delineate biochemical changes during brain development, and provide examples of how PET has been applied to study brain glucose metabolism in Rett syndrome, serotonin synthesis in autism, and GABAA receptors in Angelman's syndrome and Prader–Willi syndrome. Future application of PET scanning in the study of mental retardation might include measurements of brain protein synthesis in fragile X syndrome and tuberous sclerosis complex, two common conditions associated with mental retardation in which cellular mechanisms involve dysregulation of protein synthesis. Mental retardation results in life‐long disability, and application of new PET technologies holds promise for a better understanding of the biological underpinnings of mental retardation, with the potential to uncover new treatment options. © 2005 Wiley‐Liss, Inc. MRDD Research Reviews 2005;11:325–330.
Advanced microscopic imaging methods to investigate cortical development and the etiology of mental retardation
Authors: Haydar Tarik F.
Published: October 2005

Studies on human patients and animal models of disease have shown that disruptions in prenatal and early postnatal brain development are a root cause of mental retardation. Since proper brain development is achieved by a strict spatiotemporal control of neurogenesis, cell migration, and patterning of synapses, abnormalities in one or more of these events during prenatal development can lead to cognitive dysfunction after birth. Many of underlying causes of mental retardation must therefore be studied in developing brains. To aid in this research, live imaging using laser scanning microscopy (LSM) has recently allowed neuroscientists to delve deeply into the complex three‐dimensional environment of the living brain to record dynamic cellular events over time. This review will highlight recent examples of how LSM is being applied to elucidate both normal and abnormal cortical development. © 2005 Wiley‐Liss, Inc. MRDD Research Reviews 2005;11:303–316.
Tensile fracture morphologies of nylon‐6/montmorillonite nanocomposites
Authors: Xie Shaobo , Zhang Shimin , Zhao Bin , Qin Huaili , Wang Fosong , Yang Mingshu
Published: October 2005

Nylon‐6/montmorillonite nanocomposites with different dispersion states of clay and different clay loadings were prepared by melt processing. The nanostructure and mechanical properties were also investigated. The influence of the montmorillonite dispersion state and clay content on the tensile fracture morphology of the injection‐molded nanocomposites was studied by scanning electron microscopy. A rounded ‘cabbage‐like‐sheet’ structure was observed in the fracture surface of the well‐exfoliated nanocomposites, which was absent in the intercalated and poorly dispersed nanocomposite and neat nylon‐6. The formation of this ‘cabbage‐like‐sheet’ pattern has been attributed to the extensive plastic fibrillations of the nylon‐6 matrix, facilitated by the stress concentration and the strengthened effect caused by the well‐exfoliated clay platelets. The change in stiffness caused by the skin–core structure was also considered. The difference in the patterns observed in this present work and those reported by Uribe‐Arocha et al. (Polymer, 44, 2441 (2003)) were discussed, based on the diversity in preparation of the tensile specimens. Copyright © 2005 Society of Chemical Industry
The influence of confinement and curvature on the morphology of block copolymers
Authors: Xiang Hongqi , Shin Kyusoon , Kim Taehyung , Moon Sungin , Mccarthy T. J. , Russell T. P.
Published: October 2005

In the bulk, at equilibrium, diblock copolymers microphase separated into nanoscopic morphologies ranging from body‐centered cubic arrays of spheres to hexagonally packed cylinders to alternating lamellae, depending on the volume fraction of the components. However, when the block copolymers are forced into cylindrical pores, where the diameter of the pores are only several repeat periods of the copolymer morphology or less, then commensurability of the copolymer period and the pore diameter can impose a frustration on the microdomain morphology. In addition, due to the small pore diameter, a curvature is forced on the microdomain morphology. In combination with interfacial interactions between the blocks of the copolymer and the pore walls, the preferential segregation of one component to the walls, spatial confinement and forced curvature are shown to induce transitions in the fundamental morphology of the copolymers seen in the bulk. Lamellar morphologies transformed into torus‐type morphologies, cylinders are forced into helices, and body‐centered cubic arrays of spheres are force into helical arrays of spheres due to these restraints. The novel morphologies, not accesssible in the bulk, open a large array of nanoscopic structures that can be used as templates and scaffolds for the fabrication of inorganic nanostructured materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3377–3383, 2005
Free energy landscape and folding mechanism of a β‐hairpin in explicit water: A replica exchange molecular dynamics study
Authors: Nguyen Phuong H. , Stock Gerhard , Mittag Emil , Hu Chin‐Kun , Li Mai Suan
Published: October 2005

The free energy landscape and the folding mechanism of the C‐terminal β‐hairpin of protein G is studied by extensive replica exchange molecular dynamics simulations (40 replicas and 340 ns total simulation time), using the GROMOS96 force field and the SPC explicit water solvent. The study reveals that the system preferentially adopts a β‐hairpin structure at biologically important temperatures, and that the helix content is low at all temperatures studied. Representing the free energy landscape as a function of several types of reaction coordinates, four local minima corresponding to the folded, partially folded, molten globule, and unfolded states are identified. The findings suggest that the folding of the β‐hairpin occurs as the sequence: collapse of hydrophobic core → formation of H‐bond → formation of the turn. Identifying the folded and molten globule states as the main conformations, the free energy landscape of the β‐hairpin is consistent with a two‐state behavior with a broad transition state. The temperature dependence of the folding–unfolding transition is investigated in some detail. The enthalpy and entropy jumps at the folding transition temperature are found to be about three times lower than the experimental estimates, indicating that the folding–unfolding transition in silico is less cooperative than its in vitro counterpart. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Pulse plasma assisted atomic layer deposition of W–C–N thin films for Cu interconnects
Authors: Kim Yong Tae , Park Ji Ho
Published: October 2005

Abstract W–C–N films have been deposited on a tetraethylorthosilicate (TEOS) interlayer dielectric with atomic layer deposition (ALD) cycles of WF6–N2–CH4 gases and the exposure cycles of N2 and CH4 are synchronized with a pulse plasma. The W–C–N films on TEOS layer follow the ALD mechanism, keep a constant deposition rate of 0.2 nm/cycle from 10 to 100 cycles, and have fairly low resistivity (300 µΩ cm). As a diffusion barrier for Cu interconnection the W–C–N films maintain the amorphous phase and no Cu interdiffusion occurs even at 800 °C for 30 min. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Special issue: Advanced optical diagnostics of surfaces, nanostructures and ultrathin films
Authors: Esser Norbert
Published: October 2005

The present special issue of physica status solidi (b) is dedicated to the 65th birthday of Wolfgang Richter, now at University Rome II “Tor Vergata”, and reviews recent achievements in the field of solid state and interface optics on inorganic and organic materials.

The cover picture of the issue shows, in the background, a filled state scanning tunneling microscopy (STM) topograph of a GaAs(001)(2 × 4) surface, superimposed by a colour plot of time dependent reflectance anisotropy spectra (RAS). RAS was measured in situ during metal‐organic vapour phase epitaxy (MOVPE) growth of a 6‐fold stack of GaAsN layers on GaAs(001)(2 × 4).
Immunosuppression caused by measles virus: role of viral proteins
Authors: Kerdiles Yann M. , Sellin Caroline I. , Druelle Johan , Horvat Branka
Published: October 2005

Measles virus (MV) causes transient but profound immunosuppression resulting in increased susceptibility to secondary bacterial and viral infections. Due to the development of these opportunistic infections, measles remains the leading vaccine‐preventable cause of child death worldwide. Different immune abnormalities have been associated with measles, including disappearance of delayed‐type hypersensitivity reactions, impaired lymphocyte and antigen‐presenting cell functions, down‐regulation of pro‐inflammatory interleukin 12 production and altered interferon α/β signalling pathways. Several MV proteins have been suggested to hinder immune functions: hemagglutinin, fusion protein, nucleoprotein and the non‐structural V and C proteins. This review will focus on the novel functions attributed to MV proteins in the immunosuppression associated with measles. Here, we highlight new advances in the field, emphasising the interaction between MV proteins and their cellular targets, in particular the cell membrane receptors, CD46, CD150, TLR2 and FcγRII in the induction of immunological abnormalities associated with measles. Copyright © 2005 John Wiley & Sons, Ltd.
Clinical Add‐on: Multiple sclerosis – clinical picture and therapeutic strategies
Authors: Lins Hartmut
Published: October 2005

Multiple Sclerosis is a chronic inflammatory disorder of the central nervous system, affecting up to 1.5 % of the population in the US, UK, or Germany. Various subtypes exhibit different patterns of myelin or axonal damage and different stages of inflammation and neurodegeneration. The clinical pictures vary from rare attacks to chronically progressive disability. Current treatment options are mainly immunosuppressive or immunomodulatory [1].