bluuebunny/crossref_metadata_2025 huggingface dataset:
Coherent anti‐Stokes Raman scattering in Raman lasers and Raman wavelength converters
Authors: Vermeulen N. , Debaes C. , Thienpont H.
Published: October 2009

In this paper recent research progress on the use of Coherent Anti‐Stokes Raman Scattering (CARS) in Raman lasers and Raman wavelength converters is reviewed. The latest insights in the physical nature and behavior of CARS are addressed, and the recent performance breakthroughs in CARS‐based Raman wavelength conversion are discussed. Based on the new findings regarding the behavior of CARS, a physical explanation for apparent inconsistencies in various experimental observations of Raman wavelength conversion is provided. To conclude it is shown that these recent insights also pave the way to the development of a novel CARS‐based mechanism for reducing the heat dissipation in Raman lasers.
Financial, vocational, and interpersonal impact of living liver donation
Authors: Holtzman Susan , Adcock Lesley , Dubay Derek A. , Therapondos George , Kashfi Arash , Greenwood Sarah , Renner Eberhard L. , Grant David R. , Levy Gary A. , Abbey Susan E.
Published: October 2009

The ability to inform prospective donors of the psychosocial risks of living liver donation is currently limited by the scant empirical literature. The present study was designed to examine donor perceptions of the impact of donation on financial, vocational, and interpersonal life domains and identify demographic and clinical factors related to longer recovery times and greater life interference. A total of 143 donors completed a retrospective questionnaire that included a standardized measure of life interference [Illness Intrusiveness Rating Scale (IIRS)] and additional questions regarding the perceived impact of donation. Donor IIRS scores suggested that donors experience a relatively low level of life interference due to donation [1.60 ± 0.72, with a possible range of 1 (“not very much” interference) to 7 (“very much” interference)]. However, approximately 1 in 5 donors reported that donating was a significant financial burden. Logistic regression analysis revealed that donors with a psychiatric diagnosis at or prior to donation took longer to return to their self-reported predonation level of functioning (odds ratio = 3.78, P = 0.016). Medical complications were unrelated to self-reported recovery time. Multiple regression analysis revealed 4 independent predictors of greater life interference: less time since donation (b = 0.11, P < 0.001), income lower than CAD$100,000 (b = 0.28, P = 0.038), predonation concerns about the donation process (b = 0.24, P = 0.008), and the perception that the recipient is not caring for the new liver (b = 0.12, P = 0.031). In conclusion, life interference due to living liver donation appears to be relatively low. Donors should be made aware of risk factors for greater life disruptions post-surgery and of the potential financial burden of donation. Liver Transpl 15:1435–1442, 2009. © 2009 AASLD.
Endoscopic variceal ligation for primary prophylaxis of esophageal variceal hemorrhage in pre–liver transplant patients
Authors: Lim Eu Jin , Gow Paul J. , Angus Peter W.
Published: October 2009

Endoscopic variceal ligation (EVL) is widely used to prevent esophageal variceal bleeding in patients with advanced cirrhosis. However, the safety and efficacy of EVL in this setting have not been clearly established. This study included 300 adult patients with cirrhosis on our liver transplant waitlist who underwent upper gastrointestinal endoscopy. Esophageal varices deemed to be at high risk of bleeding were banded until eradication or transplantation. A retrospective review of patient notes and endoscopy databases was undertaken, and the number of banding episodes, complications, and patient outcomes were recorded. Forty-two of 300 patients presented with or had previous variceal bleeding prior to referral and were excluded from the analysis. Of the remaining 258 patients, 101 underwent a total of 259 banding episodes (2.6 per patient) with a median follow-up post-banding of 18.4 months per patient (a total of 150 patient years). Failed prophylaxis occurred in 2 patients (2%), and there were 3 episodes (1.2%) of acute hematemesis from band-induced ulceration. One patient (1%) had mild esophageal stricturing post-banding without dysphagia. Four of 36 patients (11%) previously found to have moderately sized or larger varices that were not banded presented with hematemesis due to variceal bleeding and were subsequently banded. None of the patients that received banding died because of bleeding or failed to receive a transplant as a result of banding complications. This study shows that in liver transplant candidates, EVL is highly effective in preventing first variceal bleed. Although banding carries a small risk of band-induced bleeding, this rate is low in comparison with the predicted rate of variceal bleeding in this population. Liver Transpl 15:1508–1513, 2009. © 2009 AASLD.
Outcome of foreign residents undergoing deceased donor liver transplantation in China: A single-center experience in Taiwan
Authors: Kuo Wei-Ting , Hsia Cheng-Yuan , Loong Che-Chuan , Liu Chin-Su , Tsai Hsin-Lin , Tseng Hsiou-Shan , Lee Rheun-Chuan , Tsou Mei-Yung , Wu Chew-Wun , Lui Wing-Yiu
Published: October 2009

Foreign residents seeking liver transplantation in China are not uncommon. The outcomes of these people have not been well reported, and the results remain unclear. A total of 64 adults [26 with end-stage liver disease (ESLD) and 38 with hepatocellular carcinoma (HCC)] who underwent donation after cardiac death (DCD) liver transplantation in China during a 5-year period were reviewed. The median follow-up period was 15.6 months. The estimated 3-month mortality rate was 4.7%. The overall survival (OS) rate of the entire patient group at 1 and 3 years was 80.3% and 63.6%, respectively. The 1- and 3-year graft survival rates were 78.5% and 64.4%, respectively. For ESLD, the 1- and 3-year OS rates were 82.5% and 82.5%, respectively. For HCC, the 1- and 3-year survival rates were 78.3% and 50.8%, respectively. The 1- and 3-year OS rates for the HCC patients who were beyond the Milan criteria (MC; n = 24) versus those who met the MC (n = 14) were 69.8% and 28.2% versus 92.9% and 92.9% (P = 0.0032). The 1- and 3-year disease-free survival rates for those beyond the MC versus those who met the MC were 56.8% and 39.0% versus 92.3% and 92.3% (P = 0.0089). The incidence of complications was 59.4%. Biliary complications (n = 24, 37.5%), vascular complications (n = 24, 37.5%), and infection (n = 16, 25%) were the 3 most frequent transplant-related complications. There were 10 patients with unsolved biliary complications, and a total of 5 patients died of posttransplant infections. In conclusion, patients with ESLD or HCC within the MC seeking DCD liver transplants in China obtained survival results comparable to those of other major cohorts from Western countries. However, a considerably high incidence of biliary complications, vascular complications, and infection substantially threatening the lives of patients is notable. Furthermore, the associated cost impact on medical resource utilization should not be overlooked. Liver Transpl 15:1579–1585, 2009. © 2009 AASLD.
Exaggerated up-regulation of tumor necrosis factor α–dependent apoptosis in the older mouse liver following reperfusion injury: Targeting liver protective strategies to patient age
Authors: Selzner Markus , Selzner Nazia , Chen Limin , Borozan Ivan , Sun Jing , Xue-Zhong Max , Zhang Jianhua , McGilvray Ian D.
Published: October 2009

Although it is becoming increasingly common to accept livers from older donors for transplantation, old livers are more damaged by hepatic ischemia and reperfusion injury (HIRI) than young livers. We hypothesized that this age-related susceptibility to HIRI is due to increased hepatocellular apoptosis driven by tumor necrosis factor α (TNFα). Young (6-week-old) and old (60-week-old) mice underwent 60 minutes of hepatic ischemia and increasing periods of reperfusion. TNFα was determined by enzyme-linked immunosorbent assay. Liver injury (enzyme release), apoptosis (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate–digoxigenin nick-end labeling staining, cytochrome C release, and caspase activation), and necrosis (hematoxylin and eosin staining) were assessed. We assessed the impact of apoptosis by blocking TNFα production or effect (pentoxifylline and TNFα receptor knockout), inhibiting apoptotic pathways (caspase inhibition), or imposing a hepatic protective strategy [glucose infusion with ischemic preconditioning (Glc/PC)]. In comparison with young livers, old livers subjected to HIRI had more pronounced liver aspartate aminotransferase release (6200 versus 3900 U/L, P = 0.02), necrosis (45% versus 25%, P = 0.03), and apoptosis with increased 30-minute TNFα release (19.02 versus 10.62 pg/mg, P = 0.03). Eliminating TNFα production reversed the effect of age, as did inhibition of apoptotic pathways with caspase inhibition. Glc/PC of old mice attenuated TNFα release (9.56 versus 19.02 pg/mg, P = 0.001) and age-related exaggerated HIRI and improved survival (60% versus 0%). In conclusion, the age-related susceptibility to HIRI is driven by an exaggerated induction of TNFα-dependent hepatocellular apoptosis. Targeting the apoptotic cascade has implications for the older donor liver population. Liver Transpl 15:1594–1604, 2009. © 2009 AASLD.
Outcome of acute liver failure in the elderly1
Authors: Schiφdt Frank V. , Chung Raymond T. , Schilsky Michael L. , Hay Eileen J. , Christensen Erik , Lee William M.
Published: October 2009

Older age is considered a poor prognostic factor in acute liver failure (ALF) and may still be considered a relative contraindication for liver transplantation for ALF. We aimed to evaluate the impact of older age, defined as age ≥ 60 years, on outcomes in patients with ALF. One thousand one hundred twenty-six consecutive prospective patients from the US Acute Liver Failure Study Group registry were studied. The median age was 38 years (range, 15–81 years). One thousand sixteen patients (90.2%) were younger than 60 years (group 1), and 499 (49.1%) of these had acetaminophen-induced ALF; this rate of acetaminophen-induced ALF was significantly higher than that in patients ≥ 60 years (group 2; n = 110; 23.6% with acetaminophen-induced ALF, P < 0.001). The overall survival rate was 72.7% in group 1 and 60.0% in group 2 (not significant) for acetaminophen patients and 67.9% in group 1 and 48.2% in group 2 for non-acetaminophen patients (P < 0.001). The spontaneous survival rate (ie, survival without liver transplantation) was 64.9% in group 1 and 60.0% in group 2 (not significant) for acetaminophen patients and 30.8% in group 1 and 24.7% in group 2 for non-acetaminophen patients (P = 0.27). Age was not a significant predictor of spontaneous survival in multiple logistic regression analyses. Group 2 patients were listed for liver transplantation significantly less than group 1 patients. Age was listed as a contraindication for transplantation in 5 patients. In conclusion, in contrast to previous studies, we have demonstrated a relatively good spontaneous survival rate for older patients with ALF when it is corrected for etiology. However, overall survival was better for younger non-acetaminophen patients. Fewer older patients were listed for transplantation. Liver Transpl 15:1481–1487, 2009. © 2009 AASLD.
Recurrence of hepatocellular carcinoma and hepatitis B reinfection in hepatitis B surface antigen–positive patients after liver transplantation
Authors: Saab Sammy , Yeganeh Melina , Nguyen Kelvin , Durazo Francisco , Han Steven , Yersiz Hasan , Farmer Douglas G. , Goldstein Leonard I. , Tong Myron J. , Busuttil Ronald W.
Published: October 2009

Hepatitis B virus (HBV) reinfection and recurrence of hepatocellular carcinoma (HCC) after orthotopic liver transplantation (OLT) are associated with increased graft failure and reduced patient survival. We evaluated the effects of both HCC recurrence and HBV reinfection on the long-term survival of these patients after OLT. One hundred seventy-five patients underwent OLT for HBV-related liver diseases and were the subjects of this retrospective study. We assessed risk factors for HBV reinfection, HCC recurrence, and survival post-OLT using univariate and multivariate analyses. During a mean follow-up of 43.0 ± 42.0 months, 88 of 175 (50.3%) patients transplanted for HBV-related liver disease had HCC prior to OLT. Thirteen (14.8%) of these patients had HCC recurrence after OLT. The mean time for recurrence of HCC was 26.1 ± 31.9 months. Twelve of 175 (6.9%) patients developed HBV reinfection after liver transplantation. The mean time for HBV reinfection was 28.7 ± 26.4 months. Ten of these 12 (83.3%) patients had HCC prior to OLT, and 5 (50%) developed recurrence of HCC. On multivariate analyses, pre-OLT HCC and recurrence of HCC post-OLT were significantly associated with HBV reinfection after transplantation (P = 0.031 and P < 0.001, respectively). HCC recurrence after OLT was associated with lymphovascular invasion (P < 0.001) and post-OLT chemotherapy (P ≤ 0.001). The 3- and 5-year survival rates were significantly decreased in patients with HBV reinfection (P = 0.007) and in patients with HCC recurrence after OLT (P = 0.03). In conclusion, pre-OLT HCC and HCC recurrence after transplantation were associated with HBV reinfection and with decreased patient survival. Hepatitis B immunoglobulin and antiviral therapy was only partially effective in preventing HBV reinfection in patients with HCC recurrence. Liver Transpl 15:1525–1534, 2009. © 2009 AASLD.
Efficacy and safety of fully covered self-expandable metallic stents in biliary complications after liver transplantation: A preliminary study
Authors: Traina Mario , Tarantino Ilaria , Barresi Luca , Volpes Riccardo , Gruttadauria Salvatore , Petridis Ioannis , Gridelli Bruno
Published: October 2009

After liver transplantation, the most common biliary complication is the anastomotic stricture, which is followed by biliary leakage. Studies have focused on the endoscopic treatment of biliary complications in transplanted patients with duct-to-duct reconstruction, showing a success rate of 70% to 80% after orthotopic liver transplantation and of 60% after living-related liver transplantation. Once the endoscopic approach fails, surgical treatment with a Roux-en-Y choledochojejunostomy is the sole alternative treatment. The aim of this prospective observational study was to analyze the efficacy and safety of fully covered self-expandable metallic stents for the treatment of posttransplant biliary stenosis and leaks in patients in whom conventional endoscopic retrograde cholangiopancreatography (ERCP) failed. From January 2008 to January 2009, 16 patients met the criteria of endoscopic treatment failure, and instead of surgery, a fully covered stent was placed. All patients had at least 6 months of follow-up (mean follow-up of 10 months). After removal, 14 patients showed immediate resolution of both the biliary stenosis and leak. After a mean of 10 months of follow-up, only 1 patient showed biliary stenosis recurrence. No major complications occurred in any of the patients, except for stent migration in 6 patients, although these presented with no clinical consequences. In conclusion, in patients not responding to standard endoscopic treatment, the placement of fully covered metal stents is a valid alternative to surgery. A cost analysis should be performed in order to evaluate whether to treat transplanted patients suffering from biliary complications with covered self-expandable metallic stent placement as first-line therapy. Liver Transpl 15:1493–1498, 2009. © 2009 AASLD.
Extended bile duct resection liver and transplantation in patients with hilar cholangiocarcinoma: Long-term results
Authors: Seehofer Daniel , Thelen Armin , Neumann Ulf P. , Veltzke-Schlieker Winfried , Denecke Timm , Kamphues Carsten , Pratschke Johann , Jonas Sven , Neuhaus Peter
Published: October 2009

For patients with irresectable hilar cholangiocarcinoma, liver transplantation (LT) is currently being reassessed because of promising data for neoadjuvant radiochemotherapy. For increased radicality, hepatectomy in combination with pancreatic head resection [extended bile duct resection (EBDR)] was performed for irresectable hilar cholangiocarcinoma during our initial experience. EBDR and LT was performed in 16 patients between 1992 and 1998. No neoadjuvant or adjuvant treatment was performed. The Union Internationale Contre le Cancer stages were I (n = 6), IIA (5), IIB (3), and IV (2). To evaluate the suspected increase in surgical radicality, a matched pair analysis was performed with 8 patients undergoing LT for hilar cholangiocarcinoma without partial pancreatoduodenectomy. The 1-, 5-, and 10-year patient survival rates after EBDR were 63%, 38%, and 38%, respectively. Twelve patients died: 2 died because of postoperative complications, 8 died because of tumor recurrence, and 2 died while recurrence-free more than 10 years after transplantation. Among the 6 stage I patients, only 1 developed tumor recurrence, but 2 died because of postoperative complications. The following factors showed a trend toward inferior survival: distant metastases, positive lymph nodes, high carbohydrate antigen 19-9 levels, and preoperative percutaneous transhepatic cholangiodrainage. When all lymph node–negative patients were considered after the exclusion of perioperative deaths, 10-year survival was 56%. In conclusion, the overall long-term survival was relatively low in our inhomogeneous cohort but favorable in patients without metastases. However, because of the increased perioperative mortality, EBDR is not recommended as a standard procedure for hilar cholangiocarcinoma instead of LT alone. To further improve the results, other approaches such as (neo)adjuvant therapy have to be increasingly investigated. Liver Transpl 15:1499–1507, 2009. © 2009 AASLD.
Intimal dissection of the hepatic artery following transarterial embolization for hepatocellular carcinoma: An intraoperative problem in adult living donor liver transplantation
Authors: Lin Tsan-Shiun , Chiang Yuan-Cheng , Chen Chao-Long , Concejero Allan M. , Cheng Yu-Fan , Wang Chih-Chi , Wang Shih-Ho , Liu Yueh-Wei , Yang Chin-Hsiang , Yong Chee-Chien
Published: October 2009

The objective of this study was to describe the relationship between intimal dissection (ID) in the recipient hepatic artery (HA) and transarterial embolization (TAE) and highlight the reconstructive methods for the different types of ID encountered in living donor liver transplantation (LDLT). Fifty-four patients with hepatocellular carcinoma underwent LDLT. ID was classified as mild, moderate, or severe, and this classification was based on the extent of intimal injury. Mild, moderate, or severe ID were defined as ID that was less than one-quarter of the circumference of the HA, had reached one-half of the circumference of the HA, or was more than one-half of the circumference of the HA or involved the entire vessel wall, respectively. The reconstructive methods were based on the severity of ID encountered. Forty patients underwent TAE before LDLT, and 23 of these patients (57.5%) had ID. Nine patients had mild ID, 6 had moderate ID, and 8 had severe ID. In the 14 patients who did not undergo TAE, 4 had ID (28.6%; 3 mild and 1 severe). The other 10 patients (71.4%) had normal HA. In mild and moderate ID, the native HA was used after trimming of the HA until a healthy segment was encountered. In severe ID, the HA was reconstructed with alternative vessels. Two HA thromboses occurred postoperatively. TAE increased the risk of developing ID 2-fold. There was no graft loss or mortality in this series due to HA complications. In conclusion, ID of the HA is associated with pretransplant TAE among hepatocellular carcinoma patients undergoing LDLT. Intraoperative recognition of this complication and trimming until good vessel quality is encountered or using alternative vessels are important. Liver Transpl 15:1553–1556, 2009. © 2009 AASLD.
Effects of obesity, diabetes, and prior abdominal surgery on resource utilization in liver transplantation: A single-center study1
Authors: Nair Satheesh , Vanatta Jason M. , Arteh Jihad , Eason James D.
Published: October 2009

Obesity, diabetes, and prior abdominal surgery are generally considered to increase the risk of liver transplantation. The aim of the present study was to define the effects of these factors on the immediate outcome after transplantation. Two hundred twenty-one consecutive liver transplants were analyzed. Twenty-eight patients were excluded. In the remaining 193 patients [mean age = 52 ± 19 years, body mass index (BMI) = 28.5, Model for End-Stage Liver Disease (MELD) score at listing = 18.7], the risk from obesity was graded as follows: (0) BMI ≤ 30, (1) BMI = 30-34.9, (2) BMI = 35-39.9, and (3) BMI ≥40. The presence of diabetes and prior abdominal surgery were each given 1 point. All the individual scores for obesity, diabetes, and prior surgery were added to produce a composite risk score for each patient. Patients were categorized into 6 risk groups, group 0 having the least risk and group 5 having the highest risk (none of the patients were in group 5). The outcome measures were death, reoperation, readmission within 90 days of transplantation, intensive care unit length of stay (LOS), hospital LOS, and packed red blood cell requirement in 48 hours. The 5 risk score groups with patients were similar in demographics and calculated MELD scores. The outcome measures in high-risk groups were similar to those in the lowest-risk group (score = 0). In the Cox regression model for LOS and survival, the composite risk score was not associated with poor survival or prolonged LOS (>3 weeks). Kaplan-Meier survival curves with log rank testing failed to show any difference in survival among different risk groups. In conclusion, patients with multiple risk factors for poor surgical outcomes can undergo successful transplantation with perioperative outcome and mortality comparable to those of low-risk patients. Liver Transpl 15: 1519–1524, 2009. © 2009 AASLD.
De novo hepatocellular carcinoma in a liver graft with sustained hepatitis C virus clearance after living donor liver transplantation
Authors: Morita Kazutoyo , Taketomi Akinobu , Soejima Yuji , Ikegami Toru , Fukuhara Takasuke , Iguchi Tomohiro , Nagata Shigeyuki , Sugimachi Keishi , Gion Tomonobu , Shirabe Ken , Maehara Yoshihiko
Published: October 2009

The occurrence of de novo hepatocellular carcinoma (HCC) after liver transplantation (LT) for advanced HCCs has been extremely limited. In this article, a case of de novo HCC in a liver graft with sustained hepatitis C virus clearance after living donor liver transplantation (LDLT) for multiple HCCs and hepatitis C cirrhosis is reported. The recipient was a 58-year-old female, and the left lobe living donor was the 30-year-old healthy daughter of the recipient. Three years after LDLT, the patient received 48 weeks of interferon treatment for recurrent hepatitis C with advanced fibrosis. The patient has shown successful viral clearance since then. However, an HCC was recognized in the liver graft during a follow-up computed tomography scan performed 6 years after LDLT, and it was surgically resected. To analyze its origin [either from the patient (metastatic) or from the living donor (de novo)], genotyping by microsatellite analysis of tissue and blood samples from the donor and recipient was performed, and it revealed that the HCC originated from the donor. To the best of our knowledge, this is the first report of de novo HCC in a liver graft with sustained hepatitis C virus clearance after LT for advanced HCCs and hepatitis C cirrhosis. Liver Transpl 15:1412–1416, 2009. © 2009 AASLD.
Comparison of pharmacokinetics of mycophenolic acid and its metabolites between living donor liver transplant recipients and deceased donor liver transplant recipients1
Authors: Baiyong Shen , Bing Chen , Weixia Zhang , Huarong Mao , Chuan Shen , Xiaxing Deng , Xi Zhan , Hao Chen
Published: October 2009

Living-donor liver transplantation (LDLT) has been considered an alternative method for treatment of patients with end-stage liver disease. However, the characteristics of pharmacokinetics of mycophenolic acid (MPA) in patients who underwent LDLT were not clear. This study was designed to compare the pharmacokinetics of MPA and its metabolites between LDLT patients and deceased donor liver transplant (DDLT) patients after oral administration of mycophenolate mofetil (MMF). Thirteen patients who underwent LDLT and 14 patients who underwent DDLT were enrolled prospectively. All patients received oral MMF administration (1.0 g, twice daily) in combination with tacrolimus (TAC). The plasma concentrations of MPA, free MPA, glucuronide (MPAG), and acyl glucuronide (AcMPAG) was determined by high-performance liquid chromatography method. There was a wide variation in various pharmacokinetic parameters of MPA and its metabolites in patients who underwent LDLT and DDLT after oral MMF administration. Although mean MPA area under the plasma concentration time curve for 0-12 hours (AUC0-12h) of MPA and MPAG in DDLT patients were higher than those in LDLT patients, there was no significant difference between the two groups. MPA concentration at 6 hours (C6h), C10h, C12h, and MPA AUC6-12h were significantly higher in DDLT group than those in LDLT group (P < 0.05). Inversely, higher free MPA AUC0-12h and significant free MPA fraction (P < 0.05) in LDLT patients were observed in DDLT patients when compared with DDLT group. AcMPAG concentrations at 4, 8, and 10 hours and AcMPAG AUC0-12h were significantly higher in the DDLT group (P < 0.05). In conclusion, after a fixed oral dose of MMF, DDLT patients had higher enterohepatic recycling contributing to total MPA exposure compared with LDLT patients. The function of glucuronide conjugation in LDLT patients was decreased compared with that in DDLT patients. Higher free MPA AUC0-12h and a significantly higher fraction of free MPA in LDLT patients suggested that a lower oral dose of MMF may be administered for patients who underwent LDLT. Liver Transpl 15:1473–1480, 2009. © 2009 AASLD.
Simplifying hepatic venous outflow reconstruction in sequential living donor liver transplantation
Authors: Chan See Ching , Lo Chung Mau , Ng Kelvin K. , Chok Kenneth S. , Fan Sheung Tat
Published: October 2009

The native liver of a familial amyloidotic polyneuropathy recipient who undergoes living donor liver transplantation used as a graft for sequential liver transplantation does not include the inferior vena cava. Implantation of this whole liver graft to a second recipient could be simplified by borrowing the experience from right liver living donor liver transplantation. With careful release of the hepatic vein from its surrounding adventitia mainly by sharp dissections, adequate lengths of these veins could be attained without compromising the native inferior vena cava. Following venoplasty of the right and middle/left hepatic vein stumps, the single cuff of the hepatic veins is anastomosed to the inferior vena cava without interpositional venous graft or patch. Satisfactory venous outflow is reliably achieved because this is the most direct outflow tract. Liver Transpl 15: 1514–1518, 2009. © 2009 AASLD.
Miscibility and Physical Properties of Poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate)/Poly(ethylene oxide) Binary Blends
Authors: Yu Fang , Nakayama Tomohiro , Nakamura Nobuo , Katsumata Kenji , Pan Pengju , Inoue Yoshio
Published: October 2009

In order to improve some inferior physical properties of bacterial poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) [P(3HB‐co‐3HHx)] by blending with PEO, the miscibility, spherulite morphology, crystallization behavior and mechanical properties of P(3HB‐co‐3HHx)/PEO binary biodegradable polymer blends were investigated. A good miscibility between P(3HB‐co‐3HHx) with a 3HHx unit content of 11 mol‐% and PEO in the amorphous state was found when the PEO weight fraction was 10 wt.‐%, while the miscibility decreased dramatically when the PEO weight fraction exceeded 20 wt.‐%. Strongly depending on the blend composition, the mechanical properties of P(3HB‐co‐3HHx) was found to be significantly improved by blending with PEO with a weight fraction of ≈5–17.5 wt.‐%.

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Designing Starch‐Based Nanospheres to Make Hydrogels with High Mechanical Strength
Authors: Tan Ying , Wang Pixin , Xu Kun , Li Wenbo , An Huiyong , Li Linglu , Liu Chang , Dong Lisong
Published: October 2009

A robust method to prepare hydrogels with high mechanical strength is presented. Core/shell nanospheres with derivatizable allyl groups in the shell were first prepared. Starch‐based nanospheres were used as crosslinker to prepare polyacrylamide hydrogels. The starch‐based nanospheres were bridged by acrylamide to form crosslink points in the hydrogel network. They possess an extremely high mechanical strength. The results show that starch‐based nanosphere hydrogels can sustain strengths of 10.34 MPa, which is 60 times greater than for a normal hydrogel. The mechanical properties of SNH can be tailored by varying the content of SN. This approach offered a new way of making functional hydrogel with biodegradable component as a substitute for tissue.

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Predicting the Long‐Term Mechanical Performance of Polycarbonate from Thermal History during Injection Molding
Authors: Engels Tom A. P. , van Breemen Lambert C. A. , Govaert Leon E. , Meijer Han E. H.
Published: October 2009

The influence of the thermal history experienced during injection molding on the mechanical properties of polycarbonate is investigated. Distributions of the yield stress as they result from inhomogeneous cooling during processing, predicted by a previously developed modeling approach, are validated and are in good agreement with experiment. Predictions of the mechanical performance for different mold temperatures during processing are also validated over a range of applied strain and deformation rates and applied stresses and forces, for simple tensile bars and an actual product. Good agreement is found. It is shown that mold temperature has a tremendous influence on the life time of polymer products, which can differ by more than two orders of magnitude.

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Nuclear applications of inorganic mass spectrometry
Authors: De Laeter John
Published: October 2009

There are several basic characteristics of mass spectrometry that are not always fully appreciated by the science community. These characteristics include the distinction between relative and absolute isotope abundances, and the influence of isotope fractionation on the accuracy of isotopic measurements. These characteristics can be illustrated in the field of nuclear physics with reference to the measurement of nuclear parameters, which involve the use of enriched isotopes, and to test models of s‐, r‐, and p‐process nucleosynthesis. The power of isotope‐dilution mass spectrometry (IDMS) to measure trace elements in primitive meteorites to produce accurate Solar System abundances has been essential to the development of nuclear astrophysics. The variety of mass spectrometric instrumentation used to measure the isotopic composition of elements has sometimes been accompanied by a lack of implementation of basic mass spectrometric protocols which are applicable to all instruments. These metrological protocols are especially important in atomic weight determinations, but must also be carefully observed in cases where the anomalies might be very small, such as in studies of the daughter products of extinct radionuclides to decipher events in the early history of the Solar System. There are occasions in which misleading conclusions have been drawn from isotopic data derived from mass spectrometers where such protocols have been ignored. It is important to choose the mass spectrometer instrument most appropriate to the proposed experiment. The importance of the integrative nature of mass spectrometric measurements has been demonstrated by experiments in which long, double beta decay and geochronological decay half‐lives have been measured as an alternative to costly radioactive‐counting experiments. This characteristic is also illustrated in the measurement of spontaneous fission yields, which have accumulated over long periods of time. Mass spectrometry is also a valuable tool in the determination of neutron capture cross‐section measurements and the application of such determinations in Planetary Science. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:845–859, 2010
Toward multipurpose NMR experiments
Authors: Schlagnitweit Judith , Zuckerstätter Gerhard , Müller Norbert
Published: October 2009

Standard phase cycled NMR pulse sequences were generalized such that for each individual step of the pulse phase cycle the free induction decay is stored separately without phase correction. This is in contrast to the usual practice, where pulse responses are phase shifted immediately (by applying a ‘receiver phase’) and co‐added as they are stored. The approach used here allows one to extract different types of NMR information, which are usually referred to as different ‘experiments’, from the same raw data set a posteriori by using complex linear combinations. Storing the free induction decays of individual phase cycle steps separately and using specific linear combinations of these data to obtain a particular type of information increase the overall efficiency of a given set of NMR experiments substantially, because all information can be derived from a single multiplexed data set. This ‘super‐experiment’ requires only as much time as the most complex of the derived specific experiments alone.

The principle of this multipurpose approach was demonstrated by performing different multiple‐quantum filtered COSY experiments. It also becomes possible to generate linear combinations, which differ from the conventionally acquired spectra a posteriori. For example, we implemented diagonal peak reduction by using zero‐ and single‐quantum filtered COSY contributions without requiring additional experiment time. Copyright © 2009 John Wiley & Sons, Ltd.
A multiresolution space‐time adaptive scheme for the bidomain model in electrocardiology
Authors: Bendahmane Mostafa , Bürger Raimund , Ruiz‐Baier Ricardo
Published: October 2009

The bidomain model of electrical activity of myocardial tissue consists of a possibly degenerate parabolic PDE coupled with an elliptic PDE for the transmembrane and extracellular potentials, respectively. This system of two scalar PDEs is supplemented by a time‐dependent ODE modeling the evolution of the gating variable. In the simpler subcase of the monodomain model, the elliptic PDE reduces to an algebraic equation. Since typical solutions of the bidomain and monodomain models exhibit wavefronts with steep gradients, we propose a finite volume scheme enriched by a fully adaptive multiresolution method, whose basic purpose is to concentrate computational effort on zones of strong variation of the solution. Time adaptivity is achieved by two alternative devices, namely locally varying time stepping and a Runge‐Kutta‐Fehlberg‐type adaptive time integration. A series of numerical examples demonstrates that these methods are efficient and sufficiently accurate to simulate the electrical activity in myocardial tissue with affordable effort. In addition, the optimal choice of the threshold for discarding nonsignificant information in the multiresolution representation of the solution is addressed, and the numerical efficiency and accuracy of the method is measured in terms of CPU time speed‐up, memory compression, and errors in different norms. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010
Effects of stress and social support on postpartum health of Chinese mothers in the United States
Authors: Cheng Ching‐Yu , Pickler Rita H.
Published: October 2009

Postpartum maternal well being across cultures has received limited research attention. We examined relationships among stress, social support, and health in 152 Chinese mothers <1 year postpartum in the United States. These mothers did not perceive high levels of stress, although they did not receive as much support as they indicated they needed; 23.7% of mothers scored high for depressive symptoms. About half of the mothers experienced interrupted sleep, decrease in memory, and lack of sexual desire. All health measures were inter‐correlated. Social support moderated the effects of stress on depressive symptoms. Culturally relevant care that is perceived as supportive may promote postpartum maternal health. © 2009 Wiley Periodicals, Inc. Res Nurs Health 32:582–591, 2009
Preliminary efficacy of a comprehensive HIV prevention intervention for abstinent adolescent girls: Pilot study findings
Authors: Morrison‐Beedy Dianne , Carey Michael P. , Seibold‐Simpson Susan M. , Xia Yinglin , Tu Xin
Published: October 2009

We developed and pilot‐tested a comprehensive HIV prevention/sexual risk reduction intervention with 54 sexually abstinent girls and estimated the effect of the intervention on three antecedents of sexual risk behavior: information, motivation, and behavioral skills. Girls ages 14–18 were randomized into either (a) an AbsPlus intervention or (b) a structurally equivalent control group. Assessments were obtained at baseline and 3 months follow‐up using audio computer assisted self‐interview. The intervention resulted in a large effect for information (d = 1.11); small to large effects for the motivational measures (d = .34–.88), and a moderate effect for a measure of behavioral skills (d = .67). The results indicate that antecedents of sexual risk behavior change were improved by a gender‐specific theoretically guided intervention. © 2009 Wiley Periodicals, Inc. Res Nurs Health 32:569–581, 2009
Nephrin—signature molecule of the glomerular podocyte?
Authors: Welsh Gavin I , Saleem Moin A
Published: October 2009

In recent years there has been an explosion of interest in the glomerular podocyte, which plays a central role in control of glomerular filtration. A host of new molecules have been identified as playing essential roles in the maintenance of podocyte integrity in both humans and mouse models. Of all of these, arguably the most pivotal is nephrin, a transmembrane receptor molecule located at the specialized podocyte cell–cell junction, termed the slit diaphragm. Mutations in this gene cause the most severe form of congenital nephrotic syndrome, and many interacting proteins have now been described to form a large multiprotein complex with complex dynamics. There is little evidence of functional nephrin expression outside the glomerulus, and there are accumulating data that nephrin is essential for the unique properties of podocyte biology. Utilizing a powerful human cell culture model, comparing wild‐type with nephrin‐null podocytes, we can show that several crucial functional properties of podocytes depend on nephrin, including insulin responsiveness and cytoskeletal reorganization. Thus, it is reasoned that nephrin is a signature molecule required to define distinct podocyte characteristics. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The prolyl isomerase domain of PpiD fromEscherichia colishows a parvulin fold but is devoid of catalytic activity
Authors: Weininger Ulrich , Jakob Roman P. , Kovermann Michael , Balbach Jochen , Schmid Franz X.
Published: October 2009

PpiD is a periplasmic folding helper protein ofEscherichia coli. It consists of an N‐terminal helix that anchors PpiD in the inner membrane near the SecYEG translocon, followed by three periplasmic domains. The second domain (residues 264–357) shows homology to parvulin‐like prolyl isomerases. This domain is a well folded, stable protein and follows a simple two‐state folding mechanism. In its solution structure, as determined by NMR spectroscopy, it resembles most closely the first parvulin domain of the SurA protein, which resides in the periplasm ofE. colias well. A previously reported prolyl isomerase activity of PpiD could not be reproduced when using improved protease‐free peptide assays or assays with refolding proteins as substrates. The parvulin domain of PpiD interacts, however, with a proline‐containing tetrapeptide, and the binding site, as identified by NMR resonance shift analysis, colocalized with the catalytic sites of other parvulins. In its structure, the parvulin domain of PpiD resembles most closely the inactive first parvulin domain of SurA, which is part of the chaperone unit of this protein and presumably involved in substrate recognition.
Enhanced red‐emitting railroad worm luciferase for bioassays and bioimaging
Authors: Li Xueyan , Nakajima Yoshihiro , Niwa Kazuki , Viviani Vadim R. , Ohmiya Yoshihiro
Published: October 2009

A luciferase from the railroad worm (Phrixothrix hirtus) is the only red‐emitting bioluminescent enzyme in nature that is advantageous in multicolor luciferase assays and in bioluminescence imaging (BLI). However, it is not used widely in scientific or industrial applications because of its low activity and stability. By using site‐directed mutagenesis, we produced red‐emitting mutants with higher activity and better stability. Compared with the wild‐type (WT), the luminescent activities from extracts of cultured mammalian cells expressing mutant luciferase were 9.8‐fold in I212L/N351K, 8.4‐fold in I212L, and 7.8‐fold in I212L/S463R; and the cell‐based activities were 3.6‐fold in I212L/N351K and 3.4‐fold in N351K. The remaining activities after incubation at 37°C for 10 min were 50.0% for I212L/S463R, 31.8% for I212L, and 23.0% for I212L/N351K, but only 5.2% for WT. To demonstrate an application of I212L/N351K, cell‐based BLI was performed, and the luminescence signal was 3.6‐fold higher than in WT. These results indicate that the mutants might improve the practicability of this signaling in bioassays and BLI.
Surviving sin papeles in post‐Katrina New Orleans: an exploration of the challenges facing undocumented Latino immigrants in new and re‐emerging Latino destinations
Authors: Drever Anita I. , Blue Sarah A.
Published: October 2009

The literature on Latino migration to new and re‐emerging destinations has emphasised the advantages of settling outside gateway cities, especially with regard to employment and affordable housing, but less attention has been given to the challenges faced by Latinos in these areas of recent settlement, particularly by those who do not have legal permission to reside in the US. By examining the situation confronting undocumented Latino migrants in post‐Katrina New Orleans, we provide insight into some of their difficulties. Using data from a quantitative/qualitative survey of post‐Katrina Latino migrants conducted by the authors, this paper highlights the obstacles undocumented immigrants face in new and re‐emerging Latino destinations because of their limited access to (a) US financial institutions, (b) a social and economic safety net, and (c) public transportation or a driver's license. It argues further that these issues pose challenges not only for recent undocumented Latinos arrivals themselves, but for the wider communities in which they are living as well. Copyright © 2009 John Wiley & Sons, Ltd.
Worst‐case control policies for (terminal) linear–quadratic control problems under disturbances
Authors: Kostina E. , Kostyukova O.
Published: October 2009

We consider linear control systems under uncertainties. For such systems we solve the problem of constructing worst‐case feedback control policies that are allowed to be corrected at m fixed intermediate time moments. We propose two types of the approximative control policies. All of them guarantee that for all admissible uncertainties the terminal system state lies in a prescribed neighborhood of a given state x* at a given final moment, and the value of the cost function does not exceed a given estimate. It is shown that computation of the estimate for each policy is equivalent to solving a corresponding convex mathematical programming (MP) problem with m decision variables. Based on the solution of the MP problem, we derive simple explicit rules (which can be easily implemented on‐line) for constructing the corresponding control policy in the original control problem. Copyright © 2009 John Wiley & Sons, Ltd.
Constructions of sparse uniform hypergraphs with high chromatic number
Authors: Kostochka A.V. , Rödl V.
Published: October 2009

A random construction gives new examples of simple hypergraphs with high chromatic number that have few edges and/or low maximum degree. In particular, for every integers k ≥ 2, r ≥ 2, and g ≥ 3, there exist r‐uniform non‐k‐colorable hypergraphs of girth at least g with maximum degree at most ⌈r kr‐1 lnk⌉. This is only 4r2 lnk times greater than the lower bound by Erdős and Lovász (Colloquia Math Soc János Bolyai 10 (1973), 609–627) that holds for all hypergraphs (without restrictions on girth). © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2010
Offline thresholds for Ramsey‐type games on random graphs
Authors: Krivelevich Michael , Spöhel Reto , Steger Angelika
Published: October 2009

In this article, we compare the offline versions of three Ramsey‐type one‐player games that have been studied in an online setting in previous work: the online Ramsey game, the balanced online Ramsey game, and the Achlioptas game. The goal in all games is to color the edges of the random graph Gn,m according to certain rules without creating a monochromatic copy of some fixed forbidden graph H. Although in general, the three online games have different thresholds, we prove that for most graphs H, the offline threshold for all three problems is m0(n) = n, where m2(H) ≔ maxH′⊆H(eH′ − 1)/(vH′ − 2). © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2010
Family sense‐making practices in science center conversations
Authors: Zimmerman Heather Toomey , Reeve Suzanne , Bell Philip
Published: October 2009

In this paper, we examine the interactional ways that families make meaning from biological exhibits during a visit to an interactive science center. To understand the museum visits from the perspectives of the families, we use ethnographic and discourse analytic methods, including pre‐ and postvisit interviews, videotaped observations of the museum visits, and coding and analysis of utterances from naturally occurring conversations. We employ an Everyday Expertise framework to understand how families use ideas and materials to make meaning from the scientific content presented in exhibits. We argue that individual and cognitive aspects of learning are fundamentally connected to the social and cultural aspects of learning; therefore, we analyze the intertwining role of individual cognitive resources, situated activities, and cultural toolkit resources that support learning interactions and processes. Findings indicate how families use a variety of knowledge types (epistemic resources) to make sense of exhibit content, how they make sense of biological content by transferring cultural epistemic resources from prior experiences, and how families use two types of scientific epistemic resources—biological facts and perceptual descriptions—as the primary means to make sense of biological exhibits. © 2009 Wiley Periodicals, Inc.Sci Ed94:478–505, 2010