Ablation of DGKα facilitates α-smooth muscle actin expression via the Smad and PKCδ signaling pathways during the acute phase of CCl4 -induced hepatic injury

Expression of α-smooth muscle actin (αSMA) is constitutive in vascular smooth muscle cells, but is induced in nonmuscle cells such as hepatic stellate cells (HSCs). HSCs play important roles in both physiological homeostasis and pathological response. HSC activation is characterized by αSMA expression, which is regulated by the TGFβ-induced Smad pathway. Recently, protein kinase C (PKC) was identified to regulate αSMA expression. Diacylglycerol kinase (DGK) metabolizes a second-messenger DG, thereby controlling components of DG-mediated signaling, such as PKC. In the present study we aimed to investigate the putative role of DGKα in αSMA expression. Use of a cellular model indicated that the DGK inhibitor R59949 promotes αSMA expression and PKCδ phosphorylation. It also facilitates Smad2 phosphorylation after 30 min of TGFβ stimulation. Furthermore, immunocytochemical analysis revealed that DGK inhibitor pretreatment without TGFβ stimulation engenders αSMA expression in a granular pattern, whereas DGK inhibitor pretreatment plus TGFβ stimulation significantly induces αSMA incorporation in stress fibers. Through animal model experiments, we observed that DGKα-knockout mice exhibit increased expression of αSMA in the liver after 48 h of carbon tetrachloride injection, together with enhanced phosphorylation levels of Smad2 and PKCδ. Together, these findings suggest that DGKα negatively regulates αSMA expression by acting on the Smad and PKCδ signaling pathways, which differentially regulate stress fiber incorporation and protein expression of αSMA, respectively.

[Acute respiratory failures caused by post-tracheotomy tracheomalacia]

A 77-year-old man underwent thoracic surgery. He had a history of two previous operations: parapharyngeal tumor removal with temporal tracheotomy 14 years ago and, two years later, a sinus surgery when, according to our anesthesia registry, intubation was extremely difficult due to stricture of the trachea underneath the tracheotomy scar. Pathology was not fully elucidated. Preoperative examinations including chest x-ray, spirogram and CT were not remarkable. The scar above the suprasternal notch was visibly sunken and retracted with respiration. Stridor was auscultated but breathing was not labored. The patient was anesthetized with propofol and intubation was smooth. During surgery anesthesia was maintained with sevoflurane, remifentanil and rocuronium. However, extubation was followed by desperate gasping and severe respiratory distress. The tracheotomy scar caved in and the airway collapsed. Continuous airway pressure via a facemask restored airway patency and improved breathing. After overnight respiratory support with non-invasive positive pressure ventilation (NPPV), patient was weaned from ventilator. Airway collapse and the two episodes of respiratory failures while under general anesthesia were attributed to post-tracheotomy tracheomalacia.

[Case of carbon monoxide poisoning with delayed encephalopathy assessed by magnetic resonance imaging]

A 21-year-old man attempted suicide by burning charcoal in a car for more than one day and was admitted to a regional hospital. On admission, his blood carboxyhemoglobin concentration was 4.4%. The patient was transferred to our emergency department because of suspected carbon monoxide poisoning. Hyperbaric oxygen therapy (HBO) was performed 5 times over 3 days. Fluid-attenuation inversion recovery (FLAIR) and diffusion-weighted (DWI) magnetic resonance imaging (MRI) performed on day 3 showed high signal-intensity lesions in the cerebral white matter. Additional HBO was performed once per day until day 16. Wecheler Memory Scale-Reviced (WMS-R) and Mini-Mental State Examination (MMSE) performed on day 17 showed his cognitive impairment. He gradually recovered the cognitive function and was discharged from the hospital without neurological sequelae on day 49. Delayed encephalopathy after acute carbon monoxide poisoning with dementia, mental impairment, and psychosis is a serious complication. Hyperintensity in FLAIR and DWI MRI predicts delayed encephalopathy and indicates cellular edema and demyelination of the white matter. One of the risk factors is prolonged carbon monoxide exposure. This case suggests that the patient, who was exposed to carbon monoxide for many hours, was at a high risk of delayed encephalopathy despite the low blood carboxyhemoglobin concentration and therefore must be monitored using MRI.

Non-hospital DOT and early diagnosis of tuberculosis reduce costs while achieving treatment success

OBJECTIVE

1) To evaluate the tuberculosis (TB) related financial burden of patients and health care providers over the course of diagnosis and treatment by choice of directly observed treatment (DOT); and 2) to examine treatment outcomes for different DOT programmes in Cambodia. SETTING AND DESIGN: Subjects were patients diagnosed with smear-positive pulmonary TB between July 2008 and January 2009 at 17 health facilities providing multiple DOT programmes. Treatment outcomes for the different DOT programmes as well as direct and indirect household costs and medical delivery costs for the treatment and care of 277 patients were examined.

RESULTS

Per patient costs of anti-tuberculosis treatment for patients with non-multidrug-resistant TB who did not have human immunodeficiency virus co-infection ranged from a high of US$1900 for in-patient DOT to a low of $395 for DOT provided at home. All costs among patients treated with hospital DOT were consistently higher than for those treated with non-hospital DOT. The percentage of treatment success was not significantly different between hospital and non-hospital DOT programmes (all >89%).

CONCLUSION

Non-hospital DOT programmes ease the financial burden on both patients and health care providers, while resulting in treatment success rates similar to those of hospital DOT.

Environmental risk factors associated with West Nile virus clinical disease in Florida horses

The objective of this study was to examine the extrinsic risk factors of West Nile virus (WNV) clinical disease in Florida horses as established from confirmed and negative horses tested within the state from 2001 to 2003. An Arboviral Case Information Form (ACF) was submitted by a referring veterinarian at the time of testing to the Florida Department of Agriculture and Consumer Services on every horse suspected of a viral encephalitis in Florida. A follow-up survey that focused on arbovirus prevention and farm ecology was created and mailed to the owner of each tested horse. Data from the follow-up survey indicated peak WNV prevalence in the late summer months in Florida. Quarter horses were the most commonly affected breed. The WNV vaccine was highly protective and natural water on the property also had a protective association. Factors that increased the risk of WNV to horses were the use of fans and a stable construction of solid wood or cement. Some risk indicators were dead birds on the property and other ill animals on the property. Data from this retrospective study have helped identify factors associated with WNV transmission in equines in Florida. Horses that have not been vaccinated and show clinical signs of arboviral infection from June to November should be tested for WNV. Horses that have been vaccinated and show clinical signs should be tested when the vaccination was administered within 1 month or greater than 6 months prior to the onset of clinical symptoms associated with WN infection.

Influence of SiO2 matrix on electronic and optical properties of Si nanocrystals

Based on ab initio density functional theory we present electronic properties and the optical response for Si nanocrystals embedded in amorphous SiO(2) networks. Quasi-spherical dots with diameters from 0.8 to 1.6 nm are investigated. The results for Si nanocrystals embedded in SiO(2) are compared with corresponding results for hydrogenated Si nanocrystals of the same size. The calculations show the influence of the interface between nanocrystal and matrix on the electronic properties. The results are compared with recent experimental data and discussed in detail. As striking features, strong reductions of the gaps and their diameter variation are predicted due to the oxide presence. Electronic confinement mainly influences the absorption edge while at higher photon energies only broad peaks at almost fixed positions occur.

Hexagon versus trimer formation in in nanowires on Si(111): energetics and quantum conductance

The structural and electronic properties of the quasi-one-dimensional In/Si(111) surface system are calculated from first principles. It is found that the symmetry lowering of the In chains is energetically favorable, provided neighboring nanowires are correlated, giving rise to a doubling of the surface unit cell both along and perpendicular to the chain direction. The recently suggested formation of hexagons within the In nanowires [C. González, F. Flores, and J. Ortega, Phys. Rev. Lett. 96, 136101 (2006)]--in clear contrast to the trimer formation proposed earlier-drastically modifies the electron transport along the In chains, in agreement with experiment.

Optical absorption of water: coulomb effects versus hydrogen bonding

The optical spectrum of water is not well understood. For example, the main absorption peak shifts upwards by 1.3 eV upon condensation, which is contrary to the behavior expected from aggregation-induced broadening of molecular levels. We investigate theoretically the effects of electron-electron and electron-hole correlations, finding that condensation leads to delocalization of the exciton onto nearby hydrogen-bonded molecules. This reduces its binding energy and has a dramatic impact on the line shape. The calculated spectrum is in excellent agreement with experiment.

Attenuation of canine warm ischemic small bowel injury by novel combination of nitric oxide donor, FK409, and cytokine suppressive anti-inflammatory agent FR167653

Organ ischemia-reperfusion injury is caused by two consecutive steps, microcirculatory disturbance and neutrophil-endothelial cell interactions, which are caused by inflammatory cytokines. We examined the hypothesis that combination therapy with a donor (FK409) of nitric oxide, one of the potent mediators with diverse roles as a vosodilator and a platelet inhibitor, together with the cytokine suppressor agent (FR167653) attenuates warm ischemic injury in canine small bowel. Small bowel ischemia was initiated by clamping the superior mesenteric artery and vein. Animals were divided into two groups: a control group (n = 5) subjected to 2-hour small bowel ischemia only, and a combination therapy group (FK/FR group, n = 5) that received FK409 (300 mcg/kg/h) plus FR167653 (1 mg/kg/h) intravenously before and after the ischemic event. We evaluated animal survival, small bowel tissue blood flow, and enzyme release from the small bowel. All controls died from severe acidosis within 2 days and all the FK/FR animals survived 7 days (P < .05). The FK/FR group recovered more than 70% of blood flow immediately after the revascularization, while the flow was less than 40% among the controls. Serum creatine phosphokinase values in the control group after reperfusion were significantly higher than those in the FK/FR group. In conclusion improvement of the microcirculation by FK409 and inhibition of cytokine release by FR167653 together attenuated warm ischemic small bowel injury.

Energetics of Si(001) surfaces exposed to electric fields and charge injection

We perform density-functional calculations on the influence of external electric fields and electrons or holes injected into surface states on the relative stability of c(4x2) and p(2x2) reconstructed Si(001) surfaces. It is shown that an electric field parallel to the [001] direction or the insertion of electrons into surface states favors the formation of p(2x2) periodicities. Our results explain recent experimental studies reporting changes of surface reconstruction of Si and Ge(001) surfaces induced by the scanning tunneling microscope and the occurrence of p(2x2) reconstructions on (001) surfaces of n-doped Si.

Ground- and excited-state properties of DNA base molecules from plane-wave calculations using ultrasoft pseudopotentials

We present equilibrium geometries, vibrational modes, dipole moments, ionization energies, electron affinities, and optical absorption spectra of the DNA base molecules adenine, thymine, guanine, and cytosine calculated from first principles. The comparison of our results with experimental data and results obtained by using quantum chemistry methods show that in specific cases gradient-corrected density-functional theory (DFT-GGA) calculations using ultrasoft pseudopotentials and a plane-wave basis may be a numerically efficient and accurate alternative to methods employing localized orbitals for the expansion of the electron wave functions.

Protection against Fas-mediated and tumor necrosis factor receptor 1-mediated liver injury by blockade of FADD without loss of nuclear factor-kappaB activation

OBJECTIVE

To investigate the role of FADD (Fas-associated protein with death domain) in Fas and tumor necrosis factor receptor 1 (TNFR1)-mediated hepatic injury and inflammatory response in vivo.

SUMMARY BACKGROUND DATA

Fas and TNFR1 are cell surface molecules that trigger apoptosis or inflammation on engagement by a specific ligand or antibody. FADD is recruited to the cytoplasmic domain of these receptors on their activation and works as a common mediator to induce apoptosis. It is known that a blockade of FADD can inhibit apoptosis mediated by Fas or TNFR1 in vitro. However, it is not known whether the blockade can prevent organ injury and whether the inflammatory cascade is affected in vivo.

METHODS

A FADD deletion mutant lacking the death effector domain was introduced into mice by transduction with an adenovirus vector, and the effect of this FADD dominant negative mutant was examined in several liver injury models.

RESULTS

Hepatic injury induced by anti-Fas monoclonal antibody or tumor necrosis factor (TNF)-alpha plus D-galactosamine was markedly ameliorated by the FADD dominant negative transduction, which abrogated the death rate. Further, the FADD dominant negative transduction efficiently blocked T cell- mediated concanavalin A-induced hepatitis while not affecting TNF-alpha production or TNF-alpha-induced nuclear factor-kappaB activation in the liver.

CONCLUSIONS

These results provide the basis for a novel therapeutic modality in which an unfavorable apoptotic process can be inhibited without affecting a favorable response for liver regeneration; this would be relevant to the clinical treatment of acute and chronic liver diseases as well as to some inflammatory disorders with hypercytokinemia, such as sepsis.

Improved survival and ammonia metabolism by intraperitoneal transplantation of microencapsulated hepatocytes in totally hepatectomized rats

BACKGROUND

We evaluated the effects of intraperitoneal transplantation of microencapsulated hepatocytes in a 3-stage total hepatectomy rat model.

METHODS

A new model of total hepatectomy was created as follows. First, the infrahepatic inferior vena cava was ligated just above the right renal vein. Seven days later, the portal vein was ligated and a portacaval shunt was established using a Teflon catheter over a venipuncture needle. Another 7 days later, total hepatectomy was completed by ligating and dividing the suprahepatic inferior vena cava, the hepatic artery, and the bile duct. Next, 4 x 10(7) hepatocytes (4% of the normal liver hepatocyte mass) isolated from male Wistar rats were microencapsulated within a collagen matrix enveloped by a 3-layer membrane of sodium alginate-poly-L-lysine-sodium alginate copolymer. Capsules containing hepatocytes (diameter, 500-800 microm) and empty capsules (control) were transplanted intraperitoneally 4 days before the total hepatectomy. Survival time and selected blood chemistry concentrations after the total hepatectomy were measured. The capsules were also examined histologically with hematoxylin and eosin staining and modified Gmelin's stain for bile pigments.

RESULTS

The survival time was greater in the rats given the microencapsulated hepatocytes than in the control rats (17.3 +/- 3 vs 3.7 +/- 0.1 hours; P <.01). The blood ammonia concentrations increased soon after total hepatectomy but remained significantly lower in the rats with microencapsulated hepatocytes (P <.05). The microcapsules contained numerous viable hepatocytes with abundant bile pigments and no lymphocytic infiltration.

CONCLUSIONS

Microencapsulated hepatocytes with an ultrathin polymer layer that protects them from inflammatory and lymphocytic reactions may facilitate their ability to function. In this study, 4 x 10(7) hepatocytes significantly prolonged the survival of rats that underwent hepatectomy and supported ammonia metabolism. Further development of this technique may permit its use in patients with hepatic failure.

Requirement of ceramide for adhesion of Helicobacter pylori to glycosphingolipids

Direct adhesion of Helicobacter pylori to immobilized glycosphingolipids (GSLs) was compared to that of their corresponding oligosaccharide-conjugated neoglycoconjugates in order to clarify the roles of the carbohydrate and lipid portions of GSLs in H. pylori adhesion. These bacteria were found to adhere to sulfatide, GM3, GalCer and LacCer, but not to ceramide, sphingomyelin, or polyacrylamides conjugated with beta-galactose, lactose, 3'-sialyllactose or 3'-sulfo-beta-galactose. Furthermore, neoglycolipids or bovine serum albumin derivatives with corresponding oligosaccharides were unable to serve as the ligands. H. pylori adhesion to GalCer with alpha-hydroxyl fatty acid was much stronger than GalCer with the non-hydroxyl fatty acid. These results suggest that H. pylori recognize the conformation of GSL with alpha-hydroxyl fatty acid on solid phase.

Prognostic significance of combined conventional and immunocytochemical cytology for peritoneal washings in endometrial carcinoma

BACKGROUND

Noncancerous cells simulating adenocarcinoma cells may interfere with the analysis of peritoneal cytology (PC) in patients with endometrial carcinoma. Immunocytochemistry (ICC) may improve the diagnosis of PC.

METHODS

PC slides from 115 patients with endometrial carcinoma were reviewed. Suspicious or positive cell clusters were recovered with a cell transfer method and were subjected to ICC for MOC-31, cytokeratin 5/6, and p53. Conventional Papanicolaou staining and ICC results were compared directly on the same cells.

RESULTS

By combined conventional and immunocytochemical PC (CONV-ICC-PC), cytodiagnosis was positive in 18 of 115 patients (15.7%) and suspicious in 3 of 115 patients (2.6%). According to a multivariate Cox regression analysis of patients with tumors confined to the uterus that included grade, myometrial invasion, cervical involvement, and CONV-ICC-PC, only CONV-ICC-PC was an independent prognostic factor (P < 0.05). A multivariate analysis for all of the patients studied that compared CONV-ICC-PC with staging variables revealed that only peritoneal metastasis (P < 0.0001) and lymph node metastasis (P < 0.01) were independent prognostic factors. When peritoneal metastases were excluded, CONV-ICC-PC (P < 0.01) and lymph node metastasis (P < 0.0025) were the independent prognostic factors. By cell transfer and p53 immunostaining in samples from 14 patients with malignant cells in their peritoneal washings, no deaths occurred among 5 patients with negative p53, whereas 5 of 9 patients with positive p53 died of disease at the time of data analysis.

CONCLUSIONS

MOC-31 immunostaining improves the diagnosis of PC in endometrial carcinoma. Positive PC is an important prognostic factor for patients with endometrial carcinoma confined to the uterus. The p53 positive cells in PC have possible prognostic significance.

Role of platelet-activating factor in hepatectomy with Pringle's maneuver

BACKGROUND

Interruption of hepatic inflow is commonly used to reduce blood loss during extensive liver resection, but may cause liver dysfunction. The present study investigated the effects of platelet-activating factor (PAF) antagonist E5880 on total liver warm ischemia and 70% hepatectomy.

METHODS

Rabbits were used in this study and were divided into four groups: group 1, those treated with only 70% hepatectomy; group 2, those treated with only 20 min Pringle's maneuver; group 3, those treated with both Pringle's maneuver and 70% hepatectomy without pretreatment; and group 4, those pretreated with PAF antagonist E5880 (0.3 mg/kg) followed by Pringle's maneuver and 70% hepatectomy. The remnant liver function was then evaluated after reperfusion.

RESULTS

Seven-day survival rates in both groups 1 and 2 were 100%. E5880 treatment significantly increased 7-day survival rate (group 4: 38% vs group 3: 0%, P < 0.05) after a combination of Pringle's maneuver and 70% hepatectomy. The elevations of serum liver enzymes (GOT, GPT, mGOT, and LDH) were significantly inhibited in group 4 at 1 and 4 h after reperfusion. Portal venous pressure and the energy charge of liver were also significantly improved in group 4, compared with those in group 3. Endothelin-1 levels of arterial and portal venous blood progressively increased after reperfusion; however, there were no significant differences between the two groups. Leukocyte infiltration into the liver was significantly inhibited in group 4.

CONCLUSION

E5880 pretreatment has protective effects on liver function after 70% hepatectomy with Pringle's maneuver in rabbits.

Hepatic resection for metastatic tumors from noncolorectal carcinoma

BACKGROUND/AIMS

The role of liver resection for hepatic metastases from noncolorectal carcinomas has yet to be clarified. The present study examines a single institutional experience of hepatic resection for noncolorectal metastases.

METHODOLOGY

From January 1987 to March 1999, 14 patients underwent curative resection for liver metastases from noncolorectal carcinomas. Records of these patients were reviewed.

RESULTS

Resections were performed for liver metastases from gastric cancers (n = 8), pancreatic cancers (n = 2), and cancers of bile duct, the papilla of Vater, kidney, and breast (n = 1, each). Six patients (5 with gastric cancers and 1 with pancreas cancer) presented with synchronous disease and 8 with metachronous disease. In the gastric cancer patients, there are 2 disease-free survivors (26 and 53 months) in the metachronous group, though all of the 5 patients with synchronous disease died within 29 months. All of the 4 patients with pancreatobiliary carcinomas died within 2 years. One case of breast cancer and another of renal cell cancer are alive without disease at 49 and 9 months, respectively.

CONCLUSIONS

For metastases from gastric cancers, better survival after hepatic resection is expected in metachronous cases than in synchronous cases. Hepatic resection may afford little benefit for patients with liver metastases from pancretobiliary cancers.

Idiopathic calcifying pancreatitis in a Japanese pediatric patient

We recently experienced a rare case of chronic pancreatitis in a 13-year-old Japanese boy. Recently, in hereditary pancreatitis patients, some mutations have been identified in the trypsinogen gene. The purpose of this study was to investigate whether the same mutations could also be found in this patient. Polymerase chain reaction (PCR)-amplified products of his cationic and anionic trypsinogen genes were examined by direct sequence analysis. The gene analysis failed to show any mutation in any exons and their flanking intronic sequences of his trypsinogen genes. These findings indicate that the chronic calcifying pancreatitis in the present patient is "idiopathic", and thus a rare case of juvenile pancreatitis.

Pharmacologic graft protection without donor pretreatment in liver transplantation from non-heart-beating donors

BACKGROUND

Non-heart-beating donors (NHBDs) are considered potential sources of transplant organs in an effort to alleviate the problem of donor shortage in clinical liver transplantation. We investigated the possibility of pharmacologic protection of hepatic allograft function from NHBDs without donor pretreatment.

METHODS

Orthotopic liver transplantation was performed using pigs. In donors, cardiac arrest was induced by stopping the respirator. Forty-five minutes after cessation of the respirator, the liver was flushed with cold lactated Ringer's solution including heparin and with the University of Wisconsin (UW) solution, and then preserved for 8 hr at 4 degrees C in the UW solution. The pigs were divided into two groups: a control group and a treated group. In the treated group, an endothelin antagonist TAK-044 was added to the UW solutions (10 mg/L), and TAK-044 (10 mg/kg body weight) and a platelet activating factor antagonist E5880 (0.3 mg/kg body weight) were also administered to the recipients.

RESULTS

TAK-044 and E5880 treatment significantly increased the 7-day survival rate of the recipients (100% vs. 17%, P<0.05). In the treated group, portal venous pressure immediately after reperfusion of the graft was significantly lower than in the control group, and postoperative increase in serum concentrations of glutamic oxaloacetic transaminase and total bilirubin was attenuated. Moreover, the energy charge and adenosine triphosphate concentration of the liver were rapidly restored after reperfusion.

CONCLUSIONS

Pharmacologic modulation with TAK-044 and E5880 avoiding donor pretreatment can improve the viability of hepatic allografts procured from NHBDs.

Clonogenic colony-forming ability of flow cytometrically isolated hepatic progenitor cells in the murine fetal liver

Stem cells are defined as cells having multilineage differentiation potential and self-renewal capability. Hepatic stem cells have aroused considerable interest not only because of their developmental importance but also for their therapeutic potential. However, their presence in the liver has not yet been demonstrated. With the use of a fluorescence-activated cell sorter (FACS) and monoclonal antibodies, we attempted to ascertain whether hepatic stem cells are present in the murine fetal liver. For this purpose, we optimized a cell isolation technique for FACS sorting of fetal liver cells. When isolated CD45 TER119 cells (the non-blood cell fraction in the fetal liver) were tested for their clonogenic colony-forming ability, mechanical dissociation (pipetting) was the most suitable cell isolation technique for FACS sorting. We confirmed that these colonies contained not only cells expressing hepatocyte markers but also cells expressing cholangiocyte markers. To identify hepatic stem cells, studies must focus on CD45TER119- cells in the murine fetal liver.

Effects of side cooling on temperature, humidity and water recycling efficiency in a culture vessel for a space experiment--results of ground experiment

Seed-to-seed experiments using dwarf plants will be conducted in Cell Biology Experiment Facility (CBEF) set up in the International Space Station (ISS). Development of a simple system to recycle water transpired by plants is necessary to save space and electrical power. A cooling system using a cooling plate that cools one side of the ventilated culture vessel to enhance water vapor condensation was developed. Effects of side cooling on air temperature, relative humidity and water recycling efficiency in the culture vessel were investigated on the ground. Decreasing the cooling plate temperature lowered temperatures of cooled side and inside air. Cooling treatment also decreased relative humidity inside the vessel less than 90% and lowered the amount of water vapor lost from the vessel through ventilation filters. This seemed to be due to the increased water vapor condensation onto the cooled side. To investigate the effect of increases in outside humidity on water recycling efficiency in the culture vessel, a water vapor transfer model was established. The calculation results indicate that an increase in relative humidity around the vessel can decrease water vapor loss from the vessel, increase water condensation onto the cooled side, and therefore, enhance water recycling efficiency in the vessel. The side cooling system seems to be useful for the CBEF in ISS because relative humidity in the CBEF is controllable.

An endothelin receptor antagonist ameliorates injuries of sinusoid lining cells in porcine liver transplantation

BACKGROUND

TAK-044 is an endothelin receptor antagonist. Whether the agent has protective effects on liver graft injuries from non-heart-beating donors is unknown.

METHODS

In donor pigs, cardiac arrest was induced by stopping the respirator. Forty-five minutes after cessation of the respirator, the liver was flushed with University of Wisconsin (UW) solution, preserved for 8 hours at 4 degrees C, and transplanted orthotopically. The pigs were divided into two groups: a control group and a drug-treated group in which TAK-044 was given in the UW solutions (10 mg/L) and was administered to recipients (10 mg/kg body weight).

RESULTS

TAK-044 treatment significantly increased recipient survival rate. After reperfusion of the graft, portal venous pressure and 15-minute retention rate of indocyanine green were significantly reduced in the drug-treated group. Electron microscopic findings indicated that TAK-044 attenuated endothelial cell injuries.

CONCLUSION

TAK-044 treatment improves the viability of livers harvested from non-heart-beating donors. The main effect of the agent is protection of endothelial cells from ischemia/reperfusion injuries.

Soluble forms of CD95 and CD95 ligand after living related liver transplantation

BACKGROUND

Soluble forms of CD95 and CD95 ligand (sCD95 and sCD95L, respectively) can increase in the serum of patients with some inflammatory disease. In this study, we investigated the serum levels of sCD95 and sCD95L in liver transplantation recipients.

METHODS

Serum levels of sCD95 and sCD95L in living related liver transplant recipients were analyzed by ELISA and their relation to the clinical findings estimated.

RESULTS

Serum samples from the recipients did not show detectable levels of sCD95L but showed significantly increased levels of sCD95. The increase of sCD95 was positively associated with that of total-bilirubin and incidence of rejection, infection, and graft ischemia.

CONCLUSIONS

The present results indicate an existence of sCD95 in the recipients of living related liver transplants. The increased serum levels of sCD95 may modify the immunological situation of the recipients after transplantation or represent the ongoing graft damage.

Chemotactic activity of soluble Fas ligand against phagocytes

A recombinant soluble form of human Fas ligand (sFasL) was tested for its chemotactic activity against human and mouse polymorphonuclear neutrophils (PMN) by the Boyden chamber method. sFasL exhibited a potent chemotactic activity against both human and mouse PMN and HL-60 cells when differentiated into neutrophils or monocytes. A neutralizing anti-FasL mAb abolished the chemotactic activity, while control mAb did not. Ligation of Fas by either IgM- or IgG-type anti-Fas mAb also induced PMN migration. PMN derived from lpr mice that express few Fas molecules did not respond to sFasL. In contrast, those derived from lpr(cg) mice that express Fas molecules with a mutated death domain normally responded to sFasL chemotaxis. These results directly indicated a chemotactic activity of sFasL against PMN and suggest a novel signaling function of Fas, which appears to be independent of the death domain-mediated apoptosis.

Transplantation of CD95 ligand-expressing grafts: influence of transplantation site and difficulty in protecting allo- and xenografts

BACKGROUND

CD95 and its ligand (CD95L) have been implicated in the regulation of immune responses. Recently, it was reported that CD95L expression prevented rejection of allogeneic grafts transplanted under the kidney capsule. In contrast, we reported that enforced CD95L expression in subcutaneously grafted cells induced acute rejection even in the syngeneic or immunodeficient hosts. In this study, we investigated whether the CD95L-expressing cells could be protected from rejection when transplanted under the kidney capsule.

METHODS

CD95-negative cells (baby hamster kidney and L5178Y lymphoma cells) were transfected with CD95L cDNA to express functional CD95L. The cells were transplanted into skin or renal subcapsular space of immunocompetent or T cell-deficient nu/nu mice.

RESULTS

The parental cells grew well in nu/nu or syngeneic mice but were rejected in allogeneic or xenogeneic immunocompetent mice. The CD95L transfectants were rejected when transplanted subcutaneously in all types of mice studied. However, when transplanted under the kidney capsule, they survived in nu/nu or syngeneic mice but were rejected in allogeneic or xenogeneic immunocompetent mice.

CONCLUSIONS

These results imply that CD95L expression may not be sufficient to protect the grafts from rejection, and the survival of CD95L-bearing grafts is substantially influenced by the site of transplantation.