Improved results for adult split liver transplantation with extended right lobe grafts: could we enhance its application?

OBJECTIVE: Split liver transplantation (SLT) allows grafting of 2 recipients with 1 allograft. Results of adult SLT have improved since its first introduction. Children benefit most from SLT, while among some adult liver transplanters there are concerns about splitting a liver, turning a good quality graft into a marginal one. We performed a single center retrospective review to address this issue. PATIENTS AND METHODS: Between June 2001 and August 2008, we performed 22 extended right liver graft (eRLG) transplantations in 21 adult patients. RESULTS: Eleven donors (50%) did not meet the Eurotransplant criteria for optimal donors. Forty-one percent of eRLG donors showed hemodynamic instability at the time of harvest. Eighteen (82%) splitting procedures were performed ex situ. The main indications for transplantation were alcoholic liver cirrhosis (32%), hepatitis C-related cirrhosis (18%), and acute liver failure (18%). Mean recipient age was 54 years (range, 17-69 years); median Model for End-Stage Liver Disease (MELD) score was 15 (range, 7-40). Patients were followed for a median of 16 months (range, 4-92 months) following transplantation. We observed 5 (23%) vascular and 3 (14%) biliary complications. Overall patient survival was 84% at 3 years; overall graft survival was 79%. For the 11 patients who had undergone transplantation after 2007, we observed a 100% patient and graft survival. CONCLUSION: After an initial learning curve and provided careful selection, exceptions to classical donor criteria for splitting can be accepted with successful outcomes comparable to those after whole liver transplantation.

Improved results for adult split liver transplantation with extended right lobe grafts: could we enhance its application?

OBJECTIVE: Split liver transplantation (SLT) allows grafting of 2 recipients with 1 allograft. Results of adult SLT have improved since its first introduction. Children benefit most from SLT, while among some adult liver transplanters there are concerns about splitting a liver, turning a good quality graft into a marginal one. We performed a single center retrospective review to address this issue. PATIENTS AND METHODS: Between June 2001 and August 2008, we performed 22 extended right liver graft (eRLG) transplantations in 21 adult patients. RESULTS: Eleven donors (50%) did not meet the Eurotransplant criteria for optimal donors. Forty-one percent of eRLG donors showed hemodynamic instability at the time of harvest. Eighteen (82%) splitting procedures were performed ex situ. The main indications for transplantation were alcoholic liver cirrhosis (32%), hepatitis C-related cirrhosis (18%), and acute liver failure (18%). Mean recipient age was 54 years (range, 17-69 years); median Model for End-Stage Liver Disease (MELD) score was 15 (range, 7-40). Patients were followed for a median of 16 months (range, 4-92 months) following transplantation. We observed 5 (23%) vascular and 3 (14%) biliary complications. Overall patient survival was 84% at 3 years; overall graft survival was 79%. For the 11 patients who had undergone transplantation after 2007, we observed a 100% patient and graft survival. CONCLUSION: After an initial learning curve and provided careful selection, exceptions to classical donor criteria for splitting can be accepted with successful outcomes comparable to those after whole liver transplantation.

Autocrine tumor necrosis factor (TNF) and lymphotoxin (LT) alpha differentially modulate cellular sensitivity to TNF/LT-alpha cytotoxicity in L929 cells.

Tumor necrosis factor (TNF) and lymphotoxin (LT) alpha are structurally and functionally related cytokines. We expressed the TNF and LT-alpha genes in murine fibrosarcoma L929r2 cells, which can be sensitized to TNF/LT-alpha-dependent necrosis by inhibitors of transcription or translation. Autocrine production of murine TNF in L929r2 cells completely downmodulated the expression of the 55- and 75-kD TNF receptors, resulting in resistance to TNF/LT-alpha cytotoxicity. Partial downmodulation of the 55-kD receptor was observed in human TNF-producing L929r2 cells. In contrast, an unaltered TNF receptor expression was found on LT-alpha L929r2 transfectants. Hence, although similar cytotoxic effects are induced by extracellularly administered TNF and LT-alpha, endogenous expression of these cytokines fundamentally differs in the way they modulate TNF receptor expression. Unlike LT-alpha, secreted by the classical pathway, TNF is first formed as a membrane-bound protein, which is responsible for receptor downmodulation. To explore whether the different pathways for secretion of TNF and LT-alpha explain this difference, we examined the effect of membrane-bound LT-alpha expression. This was obtained by exchange of the classical signal sequence of LT-alpha for the membrane anchor of chicken hepatic lectin. Membrane retention of LT-alpha resulted indeed in receptor downmodulation and TNF/LT-alpha resistance. We conclude that membrane retention of newly synthesized TNF or LT-alpha is absolutely required for receptor downmodulation and TNF/LT-alpha resistance.

Use of the yeast three-hybrid system as a tool to study caspases.

Caspases are a family of heteromeric (p20/p10) cysteine proteases with important functions in the regulation of apoptosis and inflammation. Up to now, tools to identify new substrates for caspases have mostly been limited to the random screening of in vitro translated proteins that are known, or assumed, to play a role in apoptosis. We describe the use of a yeast three-hybrid approach as a tool that adapts the classical two-hybrid system to the needs of heteromeric caspases for functional dissection of known interactions or screening for physiological substrates and inhibitors. Functional heteromeric caspase-1 was obtained by coexpression of p20(Cys285Ser) and p10 caspase-1 subunits that were each fused to the Gal4 DNA-binding domain. Upon coexpression of a third hybrid of the Gal4 activation domain and the viral caspase-1 pseudosubstrate inhibitors CrmA or p35, or the prototype physiological caspase-1 substrate prointerleukin-1beta, a functional Gal4 transcription factor could be reconstituted. In contrast, no interaction was found between CrmA or p35 and the immature p45 or p30 precursor forms of caspase-1. Therefore, the three-hybrid system might allow screening for new physiological substrates and inhibitors of heteromeric caspases.

Induction of unresponsiveness to tumor necrosis factor (TNF) after autocrine TNF expression requires TNF membrane retention.

Tumor necrosis factor (TNF) has a specific gene-inducing activity on many cell types and exerts a cytotoxic effect on a number of tumor cell lines. However, several tumor cell types are resistant to TNF-induced effects, and some of these produce TNF. We previously demonstrated that introduction of an exogenous TNF gene in the TNF-sensitive cell line L929sA induced autocrine TNF production and unresponsiveness to the cytotoxic activity of TNF. This resistance required biologically active TNF and was correlated with complete down-modulation of the TNF receptors on the cell surface. We have now characterized this process in more detail. The role of expression of the membrane-bound TNF proform and its subsequent proteolytic processing in the induction of TNF unresponsiveness was investigated. Exchange of the TNF presequence for the signal sequence of interleukin-6 resulted in production of secreted TNF, but not in induction of TNF resistance. On the other hand, expression of non-secretable, membrane-bound TNF generated complete TNF unresponsiveness. To explore whether the requirement for anchoring reflected a specific functional role of the TNF presequence, the latter was replaced by the membrane anchor of trimeric chicken hepatic lectin. Expression of this construct induced complete TNF unresponsiveness. Hence, the role of the TNF presequence in the induction of TNF unresponsiveness only involves its function as a membrane anchor, which permits oligomerization of the TNF molecule into a biologically active homotrimer.

Resistance to tumor necrosis factor (TNF) cytotoxicity by autocrine TNF production is independent of intracellular signaling pathways.

We previously showed that autocrine tumor necrosis factor (TNF) production in the TNF-sensitive L929sA fibrosarcoma cell line induced TNF resistance, which is correlated with downmodulation of both TNF receptors on the cell surface. We now analyzed whether autocrine TNF production also interfered with intracellular TNF signaling pathways. The L929sA-CAT-R55i cell line, in which cell death can be induced by controlled cytoplasmic expression of a trimeric fusion protein between chloramphenicol acetyltransferase and the intracellular domain of TNF-R55 (CAT-R55i), was supertransfected with the murine TNF gene. Expression of the latter conferred resistance to cell death induced by exogenous TNF, while cytotoxicity induced by CAT-R55i was not impaired. This demonstrates that autocrine TNF did not induce intracellular mechanisms that block TNF signaling leading to cell death. Thus the induction of TNF resistance via autocrine TNF production in L929sA cells is solely due to downmodulation of TNF receptors on the cell surface.

Crucial role of tumor necrosis factor (TNF) receptor 2 and membrane-bound TNF in experimental cerebral malaria.

Tumor necrosis factor (TNF) has been implicated in the pathogenesis of experimental cerebral malaria (CM), but the respective role of its two types of receptors has not been established. A significant increase in the expression of TNF-receptor 2 (TNFR2, p75), but not of TNFR1 (p55), was found on brain microvessels at the time of CM in susceptible animals. Moreover, mice genetically deficient for TNFR2 (Tnfr2null) were significantly protected from experimental CM, in contrast to TNFR1-deficient (Tnfr1null) mice, which were as susceptible as wild-type mice. To identify the factors involved in the protection from CM conferred by the lack of TNFR2, we assessed in both knockout and control mice the serum concentrations of mediators that are critical for the development of CM, as well as the up-regulation of intercellular adhesion molecule-1 (ICAM-1) in the brain microvessels. No significant difference in serum levels of TNF and interferon-gamma was found between infected wild-type and Tnfr1null or Tnfr2null mice. Interestingly, the pronounced ICAM-1 up-regulation and leukocyte sequestration, typically occurring in brain microvessels of CM-susceptible animals, was detected in infected control and Tnfr1null mice-both of which developed CM-whereas no such ICAM-1 up-regulation or leukocyte sequestration was observed in Tnfr2null mice, which were protected from CM. Making use of microvascular endothelium cells (MVEC) isolated from wild-type, Tnfr1null or Tnfr2null mice, we show that soluble TNF requires the presence of both TNF receptors, whereas membrane-bound TNF only needs TNFR2 for TNF-mediated ICAM-1 up-regulation in brain MVEC. Thus, only in MVEC lacking TNFR2, neither membrane-bound nor soluble TNF cause the up-regulation of ICAM-1 in vitro. In conclusion, these results indicate that the interaction between membrane TNF and TNFR2 is crucial in the development of this neurological syndrome.

Alcohol consumption among Oklahoma women: before and during pregnancy. The PRAMS Working Group. Pregnancy Risk Assessment Monitoring System.

The Pregnancy Risk Assessment Monitoring System (PRAMS) utilizes a population-based survey of Oklahoma women with a recent live birth to examine the rates of alcohol consumption before and during pregnancy. Nearly one-half of Oklahoma women report using alcohol during the three months before pregnancy and one in thirteen women consume alcohol during the three months prior to delivery. Moderate to heavy alcohol use before pregnancy was associated with additional perinatal risk factors including unintended pregnancy, inadequate prenatal care, smoking, and physical abuse. Health providers play an important role in the prevention of alcohol related birth impairments such as fetal alcohol syndrome through early detection of problem drinking, patient education and appropriate referrals. However, one in four Oklahoma mothers report their health care provider did not talk to them about the harmful effects alcohol can have on their baby.

Generation and biological characterization of membrane-bound, uncleavable murine tumor necrosis factor.

Tumor necrosis factor (TNF) is produced as a membrane-bound, 26-kDa proform from which the mature, 17-kDa TNF subunit is released by proteolytic cleavage. In order to compare the biological activity of membrane-bound versus soluble TNF, mutational analysis of potential cleavage sites in murine TNF was carried out. The biological activity was assessed after transfection in L929 cells. Deletion of the first nine codons of the mature part of the murine TNF gene still led to the production of secretable TNF, indicating alternative cleavage sites separate from the -1/+1 junction. However, an additional deletion of 3 amino acids, generating TNF delta 1-12, resulted in a membrane-bound form of TNF. Site-directed mutagenesis revealed Lys11 as the critical residue for alternative cleavage. Mutation of this residue to Glu in a TNF delta 1-9 mutant gave rise to uncleavable, membrane-bound TNF with biological activities similar to wild-type TNF. Induction of apoptosis, proliferation, or cytokine production by triggering of either 55-kDa or 75-kDa TNF receptors in appropriate cell lines occurred efficiently both with soluble and with membrane-bound TNF. The latter was, however, less active in the cytotoxic assays on U937 cells in which the 75-kDa TNF receptor is not signaling, but contributes to maximal TNF activity by ligand passing. This indicates that membrane-bound TNF cannot be passed from the 75-kDa to the 55-kDa TNF receptor.

TNF-induced intracellular signaling leading to gene induction or to cytotoxicity by necrosis or by apoptosis.

TNF-induced apoptosis, e.g. in murine PC60 cells, requires the TNF receptor p55 (TNF-R55) and the TNF receptor p75 (TNF-R75); the latter even does not have to be triggered. The intracellular domain of TNF-R55 can be activated in the cytosol by linking it to the trimeric CAT protein; induction of this fusion protein leads to a full TNF response. A new MAP kinase, p38, has been shown to be also activated by TNF. This activation is essential for gene induction, but not for cytotoxicity in L929 cells. TNF treatment of L929 leads to reactive oxygen formation in the mitochondria, resulting in cell death by necrosis. TNF treatment of many other cell types results in apoptosis, and this process involves activation of one or more ICE homologs (IHO). In the mouse, seven cysteine proteases of the IHO family have been cloned and partially characterized. One or more of these IHOs is involved in cell killing by proteolysis of critical substrate(s). One substrate, which may be a key effector molecule in the apoptotic process, is PITSLRE kinase.

MSS1, a nuclear-encoded mitochondrial GTPase involved in the expression of COX1 subunit of cytochrome c oxidase.

Mutations in the MSS1 gene render the yeast cells respiratory deficient only in the presence of the PR454 mutation (paromomycin resistance) in the mitochondrial 15 S ribosomal RNA gene. The MSS1 gene product works in association with the small subunit of mitoribosomes and seems to play some part in mitochondrial translation. The block in the splicing of introns of cytochrome c oxidase subunit 1 could result from a specific impeding of the translation of maturases. Comparison of the MSS1 putative protein with data libraries revealed that it contains, in its second half, the consensus sequences characteristic of GTP binding proteins and is very homologous to the bacterial "genes 50K".

QRI8, a novel ubiquitin-conjugating enzyme in Saccharomyces cerevisiae.

We have cloned and sequenced the gene encoding a novel ubiquitin-conjugating enzyme in Saccharomyces cerevisiae. Disruption of this gene shows that it is not essential for cell viability.

Expression of an exogenous tumor necrosis factor (TNF) gene in TNF-sensitive cell lines confers resistance to TNF-mediated cell lysis.

TNF, a cytokine with cytotoxic activity on a variety of tumor cells, is mainly produced by macrophages; however, some tumor cell types of non-macrophage origin, apparently resistant to TNF-mediated cell lysis, can also produce TNF. It is not clear whether these cells were TNF-resistant a priori or whether protective mechanisms against toxicity of autocrine TNF may be induced in TNF-producing cells. Murine L929sA fibrosarcoma cells, which are highly sensitive to TNF cytotoxicity, were transfected with the neomycin resistance (neor) gene, alone or in combination with the human (h) or the murine (m) TNF gene. All exogenous genes were under control of the constitutive SV40 early promoter. After cotransfection, the number of neor colonies was 10 to 100% as compared with the number of colonies upon transfection with the neor gene alone. An appreciable fraction of these colonies (50-100%) constitutively produced biologically active TNF. mTNF-producing L929 cells were fully TNF resistant, whereas hTNF-producing cells showed partial TNF resistance. Specific TNF binding could not be detected on mTNF-producing L929sA transfectants, whereas hTNF-producing cells showed reduced TNF binding. Apparently, TNF gene expression, even in a priori TNF-sensitive cells, can induce mechanisms to prevent toxicity by both autocrine and exogenous TNF. No TNF resistance was induced by expression of a gene sequence encoding the 9-kDa membrane-bound presequence part of the 26-kDa mTNF proform. Expression of a mutant 26-kDa TNF gene coding for a quasi-inactive mature mTNF induced only weak TNF resistance as compared with the complete resistance obtained after transfection with the wild-type gene. These findings show that the membrane-bound TNF presequence as such is not sufficient for induction of TNF resistance and imply that the active site of mature TNF is involved in modulation of TNF responsiveness upon autocrine TNF production.

Trends in publicly financed prenatal and related services, 1975-1984.

We studied trends in Title V and health department financed prenatal and related services in U.S. countries from 1975-1984, years during which Medicaid and health insurance coverage for poor women were eroding. Information on prenatal services was obtained from background reports and telephone interviews with staff of State Maternal and Child Health programs. The number of counties providing prenatal care, particularly comprehensive care, rose considerably from 1975 to 1984; the largest rise occurred between 1982 and 1984. Federal initiatives accounted for about 25 percent of the increase in comprehensive care, while state-funded initiatives were responsible for the modest rise in counties offering routine care. The number of counties providing related components of care such as risk assessment and referral, obstetric or pediatric linkage with prenatal care, and outreach also rose markedly during the study years. Despite these secular trends, forty percent of U.S. counties did not offer prenatal care in health department operated or funded sites in 1984.

The MSS51 gene product is required for the translation of the COX1 mRNA in yeast mitochondria.

The MSS51 gene product has been previously shown to be involved in the splicing of the mitochondrial pre-mRNA of cytochrome oxidase subunit I (COX1). We show here that it is specifically required for the translation of the COX1 mRNA. Furthermore, the paromocyin-resistance mutation (P454R) which affects the 15S mitoribosomal RNA, interferes, directly or indirectly, with the action of the MSS51 gene product. Possible roles of the MSS51 protein on the excision of COX1 introns are discussed.

[Dupuytren's disease. Review of 326 surgically treated patients]. / Maladie de Dupuytren. Revue de 326 patients opérés.

The COC (Orthopedic Society of Charleroi) has presented an analysis of operated cases. We have taken 326 files into account. The pre-operative evaluation is based upon the classification by Tubiana, Michon and Thomine. The analysis pays special attention to the post-operative results in terms of several factors: the age, the stage of illness, the extent of illness and the improvement. For this final summing up, we put forward criteria which for us are better in the evaluation of the final result.