Risk factors for intraoperative portal vein thrombosis in pediatric living donor liver transplantation

Pathologic changes of the recipient native portal venous system may cause thrombosis of the portal vein, especially in pediatric living donor liver transplantation (LDLT). This study assessed the utility of Doppler ultrasound (US) for the detection of intraoperative portal vein occlusion and identification of predisposing risk factors in the recipients. Seventy-three pediatric recipients who underwent LDLT at Chang Gung Memorial Hospital, Taiwan, from 1994 to 2002 were included. Preoperative and intraoperative Doppler US evaluation of the portal vein was performed. Age, body weight, native liver disease, type of graft, graft recipient weight ratio (GRWR), type of portal anastomosis, portal velocity, portal venous size and presence of portosystemic shunt were analyzed for statistical significance of predisposing risk factors. Eight episodes of intraoperative portal vein thrombosis, with typical findings of absent Doppler flow in portal vein and prominent hepatic artery with a resistant index lower than 0.5 (p < 0.001), were detected during transplantation, which was then corrected by thrombectomy and re-anastomosis. Children age < or =1 yr (p = 0.025), weight < or =10 kg (p = 0.024), low portal flow < or =7 cm/s (p = 0.021), portal venous size < or =4 mm (p = 0.001), and GRWR >3 (p < 0.017) were all risk factors for intraoperative portal vein thrombosis. Doppler US is essential in the preoperative evaluation, early detection and monitoring of outcome of the portal vein in liver transplant.

Systemic thrombolytic therapy for late-onset portal vein thrombosis after living-donor liver transplantation

BACKGROUND

There have been few reports of noninvasive treatment for portal vein thrombosis (PVT) after liver transplantation.

METHODS

One adult patient and four pediatric patients developed PVT 5, 14, 14, 16, and 43 months after living-donor liver transplantation, respectively. All five of the patients received a 10-day course of systemic thrombolytic therapy with recombinant tissue plasminogen activator.

RESULTS

After the treatment was completed, successful portal vein recanalization was demonstrated on ultrasonography or multidetector three-dimensional computed tomography angiography in all five cases.

CONCLUSION

Noninvasive treatment with systemic recombinant tissue plasminogen activator should be considered for selected patients with late-onset PVT after liver transplantation.

Duct-to-duct biliary reconstruction in adult-to-adult living donor liver transplantation

In living donor liver transplantation (LDLT), Roux-en-Y hepaticojejunostomy has been a standard technique for biliary reconstruction because the majority had been pediatric patients with biliary atresia. Adult-to-adult LDLT using the right lobe graft has recently been developed and we introduced duct-to-duct biliary reconstruction (hepaticohepaticostomy) in such cases. The aim of this study is to evaluate the feasibility of this procedure in adult-to-adult LDLT. From August 2000 to October 2001, five patients underwent adult-to-adult LDLT using the right hepatic lobe and were followed for more than 6 months at our institution. All patients underwent duct-to-duct biliary reconstruction (single hepaticohepaticostomy in one, multiple in four). For the grafts with multiple bile ducts, various techniques were used for reconstruction. In all patients, oral intake could be started early after the operation, and biliary leakage was not encountered. One patient developed two episodes of acute cholangitis who later developed biliary anastomosis stricture which required percutaneous dilatation at 11 months postop. However, otherwise, there were no infectious complications postoperatively. We conclude duct-to-duct biliary reconstruction is feasible and effective in adult-to-adult LDLT.

Vertical portal vein clamping in right hepatic lobectomy for live donation or neoplasm

A modified technique is described in clamping the right branch of the portal vein in right hepatic lobectomy for live donation or neoplasm that allows flush division of the origin of the right branch without causing portal vein stenosis.

Changes in the weights of the accessory sex organs in male CD/IGS rats (Rattus norvegicus) after castration

This study was designed to detect time-course changes in the weights of accessory sex organs after castration. Crj:CD(SD) IGS rats (Rattus norvegicus) were castrated at age of 6-weeks and sacrificed within 14 days of the procedure. The ventral prostate, vesicular gland, bulbospongiosus/levator ani muscle, glans penis and bulbourethral glands were then weighed. The ventral prostate and vesicular gland had significantly decreased in weight 8 and 6 days after castration, respectively. The other organs did not decrease in weight significantly between time periods though there was an overall decrease in weight.

Living-donor liver transplantation for Caroli's disease with intrahepatic adenocarcinoma

A 36-year-old woman who had Caroli's disease with refractory cholangitis and complicated intrahepatic cholangiocarcinoma was successfully treated with living-donor liver transplantation. Preoperative computed tomography and ultrasonography showed a small nodule in the dilated intrahepatic bile duct. In the resected liver specimen, a small papillary tumor was located in the dilated intrahepatic bile duct of the right lobe. The pathological finding revealed a well differentiated papillary adenocarcinoma without invasion to the parenchyma. The patient is currently doing well 2.5 years after transplantation, with no signs of recurrence of the disease. For Caroli's disease, we believe we can achieve good results with liver transplantation, not only for cholangitis but also for the carcinoma when it is localized in the liver and the patient is carefully followed up.

Preputial separation and glans penis changes in normal growing Crj: CD (SD) IGS rats

This study was designed to detect preputial separation and glans penis changes in normal growing SD rats. We examined the changes until 53 days after birth. The glans penis surface changed from a protruding os penis structure to a W shape, and from a W shape to a flattened surface with age. The protruding os penis structure changed gradually to the W shape from postnatal day (PND) 30, and all rats had the W shape by PND 35. The flattened surface was observed from PND 39, and all rats had this structure by PND 44. In all rats, the day of complete preputial separation exactly corresponded to the day of appearance of the flattened surface.

Weaning of immunosuppression in living donor liver transplant recipients

BACKGROUND

Some reported studies have indicated the possibility of immunosuppression withdrawal in cadaveric liver transplantation. The aim of this study was to evaluate the possibility and feasibility of weaning living donor liver transplant recipients from immunosuppression.

METHODS

From June of 1990 to October of 1999, 63 patients were considered to be weaned from immunosuppression. They consisted of 26 electively weaned patients and 37 either forcibly or incidentally weaned patients (nonelective weaning) due to various causes but mainly due to infection. Regarding elective weaning, we gradually reduced the frequency of tacrolimus administration for patients who survived more than 2 years after transplantation, maintained a good graft function, and had no rejection episodes in the preceding 12 months. The frequency of administration was reduced from the conventional b.i.d. until the start of weaning to q.d., 4 times a week, 3 times a week, twice a week, once a week, twice a month, once a month, and finally, the patients were completely weaned off with each weaning period lasting from 3 to 6 months. The reduction method of nonelective weaning depended on the clinical course of each individual case. When the patients were clinically diagnosed to develop rejection during weaning, then such patients were treated by a reintroduction of tacrolimus or an additional steroid bolus when indicated.

RESULTS

Twenty-four patients (38.1%) achieved a complete withdrawal of tacrolimus with a median drug-free period of 23.5 months (range, 3-69 months). Twenty-three patients (36.5%) are still being weaned at various stages. Sixteen patients (25.4%) encountered rejection while weaning at median period of 9.5 months (range, 1-63 months) from the start of weaning. All 16 were easily treated with the reintroduction of tacrolimus or additional steroid bolus therapy.

CONCLUSIONS

We were able to achieve a complete withdrawal of immunosuppression in some selected patients. Although the mechanism of graft acceptance in these patients has yet to be elucidated, we believe that a majority of long-term patients undergoing living donor liver transplantation may, thus, be potential candidates to be successfully weaned from immunosuppression.

Strain sensitivity differences in the Hershberger assay

The Hershberger assay is a test method for detecting androgenic or antiandrogenic properties based on alterations in the weights of accessory sex organs in castrate male animals. We performed this study to examine strain sensitivity differences in the Hershberger assay. Flutamide (FLU) at a dose of 3.2 mg/kg was administered to castrated F344, SD, or Wistar rats, in addition to testosterone propionate (TP) administered at a dose of 0.4 mg/kg. Although FLU significantly attenuated the TP-induced increase in glans penis weight in SD and Wistar rats, this attenuation was not observed in F344 rats. Statistical analysis showed differences among the strains in all sex accessory organ weights. The interaction in the ventral prostate, seminal vesicle, and glans penis weights was significant between SD and F344 rats, and between Wistar and F344 rats, but not between SD and Wistar rats. F344 rats were less suitable than SD or Wistar rats for detecting FLU-induced changes.

Experiences on persistent organic pollutants under the Law concerning the Examination and Regulation of Manufacture, etc. of Chemical Substances, Japan, with references to biodegradation and bioaccumulation

OBJECTIVES

The purpose of this report is to outline current regulations to control chemical environmental pollution in Japan, with special references to internationally defined 12 persistent organic pollutants (POPs).

MATERIALS

Law concerning the Examination and Regulation of Manufacture, etc. of Chemical Substances [(LERCS); enacted in 1973] and related administrative activities of monitoring of the environment in Japan.

RESULTS

Among the existing chemicals identified by the 1972 Chemicals Inventory, LERCS designates aldrin, chlordanes, DDT, dieldrin, endrin, HCB, PCBs, poly(Cln; n = 3 or more)-chlorinated naphthalene (PCNs) and bis(tributyltin) oxide (TBTO) as Class 1 specified chemical substances which are under strict regulation, such as prohibition of production, import, or use in principle. In addition LERCS designates 23 Class 2 specified chemical substances (including 13 tributyltin and seven triphenyltin compounds) for which notification of scheduled and past production, compliance with technical guidelines and compliance with labeling standards is requested. When compared with the 12 POPs, the designation covers most of them except for mirex and toxaphene, which have never been used in Japan. The regulation has been effective in reducing substantially the levels of the designated chemical substances (and therefore the 12 POPs except for dioxins and furans) in the general environment in Japan. Efforts are currently focused under a newly enacted law to reduce the emission of the two non-intentionally produced pollutants of dioxins and furans, especially from city waste incinerators, so that emission in 2002 should be 10% of that in 1997.

CONCLUSION

Regulations to control chemical emissions have been effective in reducing POPs levels in the environment in Japan, and further efforts have been made under a new law to reduce the emission of dioxins, furans and co-planar PCBs.

Development of non-radio isotopic endpoint of murine local lymph node assay based on 5-bromo-2'-deoxyuridine (BrdU) incorporation

Allergic contact dermatitis is a serious health problem. Over the last decade, the murine local lymph node assay (LLNA) has been developed to detect chemical allergens, and international validation studies have been conducted. We have tried to establish an alternative non-radioisotopic endpoint for the LLNA by using 5-bromo-2'-deoxyuridine (BrdU) incorporation in place of radioisotopes, such as [3H]thymidine, employed in the standard method. BrdU was given as a single administration at 5 mg/animal 2 days following three consecutive daily applications of a test chemical. BrdU incorporation into draining lymph node cells was measured using an enzyme immunosorbent assay technique. In this study, p-benzoquinone(PBQ), trimellitic anhydride (TMA), citral(CT) and dextran (DEX) were used as pilot chemicals. PBQ, TMA and CT, which are classified as moderate to strong sensitizers in the guinea pig maximization test and were positive in the original LLNA, were also found to elicit positive responses in the alternative LLNA using BrdU incorporation. In contrast, DEX tested negative in the modified assay consistent with previous guinea pig and LLNA data. Consequently, the modified LLNA endpoint using BrdU incorporation may represent a useful alternative to the standard assay in situations, where there is a need to avoid the use of radioisotopes.

Analysis of alloreactivity and intragraft cytokine profiles in living donor liver transplant recipients with graft acceptance

Although some previous studies have indicated the possibility of immunosuppression withdrawal in clinical liver transplantation, the mechanism of graft acceptance is not clear. The aim of this study is to elucidate the alloreactivity against the donor and intragraft cytokine profiles in living donor liver transplant (LDLT) recipients with graft acceptance. In October 1999, we had 23 patients who survived without immunosuppression after LDLT with a median drug-free period of 25 months (range: 3-69 months). They consisted of six patients who were electively weaned by an elective weaning protocol and 17 either forcibly or accidentally weaned patients due to various causes but mainly due to infection. We evaluated the alloreactivity against the donor in these patients by a mixed lymphocyte reaction and intragraft cytokine profiles by real-time reverse transcriptase-polymerase chain reaction. The development of donor-specific hyporeactivity was observed in the patients with graft acceptance. The cytokine pattern in the supernatant of the culture medium revealed a down regulation of T helper (Th) 1 cytokine INF gamma against the donor while no significant difference was seen in Th2 cytokine IL-10. Regarding the intragraft cytokine profiles, we could find no amplification of Thl cytokines (IL-2, INF y) and IL-4 while some of the patients revealed a gene expression of IL-10 with no significant difference from that of the normal, untransplanted liver specimen. In addition, no difference was observed in any other cytokines (IL-1beta, IL-8, IL-15, TNFalpha) compared with those of the normal controls. We propose that the down regulation of Th1 cytokine is one possible mechanism of graft acceptance in LDLT recipients.

Structural essentials of xenoestrogen dialkyl phthalates to bind to the estrogen receptors

Xenoestrogen dialkyl phthalates, C(6)H(4)(COOC(n)H(m))(2), lack the phenolic hydroxyl group that is an essential structural component of the steroid A ring of 17 beta-estradiol. In order to examine whether dialkyl phthalates imitate the steroid structure, we have synthesized a series of 4-hydroxyl derivatives of dialkyl phthalates. The compounds were examined for their ability to displace [(3)H]17 beta-estradiol from the recombinant human estrogen receptor, which was expressed on Sf9 cells using the vaculovirus expression system. Dialkyl 4-hydroxyl phthalates were found to exhibit several-fold higher binding affinities compared to phthalates without the 4-hydroxyl group. From the analyses of receptor binding modes of dialkyl phthalates with and without the 4-hydroxyl group, it was deduced that the phthalic benzene ring mimics the steroid A ring. A biphasic binding curve observed for dicyclohexyl phthalate was also depicted by its 4-hydroxyl derivative, but it increased binding affinity only at the high affinity binding site. These data suggest that the phthalate benzene moiety recognizes the core of the estrogen receptor binding site and the hydrophobic interaction of the dialkyl moiety substantiates the binding characteristics of the phthalates. The present data indicate that even chemicals with slight structural analogy and weak receptor affinity can perturb the endocrine system when administered in high concentrations.

Immature rat uterotrophic assay of bisphenol A

We used the immature rat uterotrophic assay to determine the estrogenicity of bisphenol A (BPA). We administered BPA (in sesame oil) to rats subcutaneously (sc; 0, 8, 40, and 160 mg/kg/day) or orally (0, 40, 160, and 800 mg/kg/day) for 3 days beginning on postnatal day (PND) 18; rats were sacrificed 24 hr after the last administration. Uterine wet, blotted, and relative weights increased in all groups given BPA sc. After oral administration, uterine relative weight increased in 160 and 800 mg/kg BPA groups, and wet and blotted weights increased in the 800 mg/kg BPA group. Plasma concentrations of BPA at 1 hr after the last administration were detected in all groups given BPA sc and in groups given 160 and 800 mg/kg BPA orally, with a dose-response effect. The study was then reproduced under the same conditions. After sc injections, uterine wet and blotted weights increased in the 40 and 160 mg/kg BPA groups, and relative weight increased in all groups given BPA sc. By contrast, uterine wet, blotted, and relative weights increased only in the 160 and 800 mg/kg oral BPA groups. Also, to examine time-course changes in uterine weight, we administered BPA (in sesame oil) sc from PND 18 to PND 20 for 3 days at doses of 0, 8, 40, and 160 mg/kg/day; uterine weights were then measured at 6, 12, 18, and 24 hr after the last administration. Uterine wet, blotted, and relative weights increased in all BPA groups at 6 and 24 hr and in 40 and 160 mg/kg BPA groups at 12 hr. By contrast, at 18 hr, uterine wet, blotted, and relative blotted weights increased in all BPA groups and relative wet weight increased in 40 and 160 mg/kg BPA groups. The percentage increases in uterine wet and relative weights of 40 and 160 mg/kg BPA groups at 6 hr were higher than those at 24 hr relative to the controls, but the coefficient of variation in these weights in the group given 8 mg/kg BPA at 24 hr was smaller than that at 6 hr. These findings demonstrate BPA-induced uterotrophy in the immature uterotrophic assay in rats administered 8 mg/kg/day sc and in rats given 160 mg/kg/day orally, and suggest that the autopsy at 24 hr after the last administration is suitable.

[Weaning of immunosuppression in living-related liver transplantation]

In our experience of living donor liver transplantation (LDLT), some recipients could be successfully weaned from any immunosuppressant in case of various situations like severe infectious complications, posttransplant lymphoproliferative disorder, and noncompliance. Based on such unexpected experiences, we started the intentional weaning of immunosupressants after LDLT. The patients were selected among the recipients who had been followed up longer than two years with stable normal graft function, and without any rejection episodes in the latest one year. So far, 26 cases were enrolled into this program, and 6 cases could be intentionally weaned from any immunosuppressants. Four recipients unfortunately had a rejection episode during the weaning. Immunosuppressants were again returned to the pre-weaning level in these recipients, and the rejection could be treated without any persistent dysfunction of the graft. Clear discrimination of the recipients who will be or will not be able to be weaned from immunosuppression is still impossible. Mixed lymphocyte reaction showed tendency of low response to the donor, but the result is not stationary in all recipients. Identification of suitable parameters to promise the possibility of weaning is a big problem to be solved in the future.

Structural requirements of para-alkylphenols to bind to estrogen receptor

Octyl- and nonylphenols in the environment have been proposed to function as estrogens. To gain insight into their structural essentials in binding to the estrogen receptor, a series of phenols with saturated alkyl groups at the para position, HO-C6H4-CnH2n+1 (n = 0-12), were examined for their ability to displace [3H]17beta-estradiol in the recombinant human estrogen receptor, which was expressed in Sf9 cells using the vaculovirus expression system. All tested para-alkylphenols were found to bind fully to the estrogen receptors in a dose-dependent manner. The interaction of alkylphenols with the receptor became stronger with increase in the number of the alkyl carbons and the activity was maximized with n = 9 of nonylphenol. Phenol (n = 0) exhibited weak but full binding to the receptor, whereas anisole with a protected phenolic hydroxyl group was completely inactive. Also, alkanes such as n-octane, 2,2, 4-trimethylpentane corresponding to tert-octane, and n-nonane exhibited no binding. The results indicate that the binding of para-alkylphenols to the estrogen receptor is due to the effect of covalent bonding of two constituents of the phenol and alkyl groups, which correspond to the A-ring and hydrophobic moiety of the steroid structure, respectively. When alkylphenols were examined for their receptor binding conformation by 1H-NMR measurements and ab initio molecular orbital calculations, it was suggested that nonbranched alkyl groups are in an extended conformation, while branched alkyl groups are in a folded conformation. These results suggest that branched and nonbranched alkyl moieties of alkylphenols interact differently with the lipophilic ligand binding cavity of the estrogen receptor when compared to the binding of 17beta-estradiol.

Idiopathic thrombocytopenic purpura after a living-related liver transplantation

BACKGROUND

Idiopathic thrombocytopenic purpura (ITP) is a rare complication after liver transplantation. We describe three cases of ITP in pediatric patients after a living-related liver transplantation (LRLT).

METHODS

Of 266 patients who underwent an LRLT between June 1990 and June 1996, severe thrombocytopenia developed in three pediatric patients after transplantation, and ITP was also diagnosed. The original disease was biliary atresia in all cases, and the patients were given a partial liver graft from a living-related mother and subsequently treated with tacrolimus and low-dose steroids as an immunosuppressive regimen.

RESULTS

The duration until the onset of ITP after transplantation in the three cases was 1 day, 3 months, and 13 months, respectively. The platelet-associated IgG levels increased in all cases. A preceding viral infection was suspected in two of the three cases. All patients were treated with intravenous gamma globulin with a transient recovery of thrombocytopenia in two cases and a sustained recovery in another.

CONCLUSIONS

Transplant clinicians need to be aware of the possibility of ITP complication because a sudden onset of severe thrombocytopenia can occur even in patients who are apparently doing well after undergoing an LRLT.

Binding characteristics of dialkyl phthalates for the estrogen receptor

Dialkyl phthalates have been suggested to function as xenoestrogen. To explore the structural essentials, a series of ring and alkyl-chain isomers of dialkyl phthalates C6H4(COOCnHm)2 were examined for their ability to displace [3H]17beta-estradiol in the recombinant human estrogen receptor expressed on Sf9 vaculovirus. Compounds with an alkyl chain of more than C3 (n = 3) exhibited a distinct full receptor binding in a dose-dependent manner. When the ring isomers of C3-diallyl (-CH2-CH=CH2) derivatives, namely diallyl phthalate, diallyl isophthalate, and diallyl terephthalate, were examined, the ortho isomer of diallyl phthalate was most potent to bind to the estrogen receptor. The interaction with the estrogen receptor was optimized with dibutyl phthalates of C4. The conformational studies by 1H-NMR measurements and ab initio molecular orbital calculations have suggested that the structure mimics the interface of steroid A and B/C rings of 17beta-estradiol. Dicyclohexyl phthalate bound to the estrogen receptor with a biphasic binding curve, suggesting the compound discriminates two different receptor conformations.

[An immunohistochemical study of the relationship between p53 expression and the DNA ploidy pattern using image cytometry in colorectal carcinoma]

We studied p53 expression in 46 colorectal carcinomas by immunohistochemistry. We examined the relationship between p53 expression and the pathological findings, the prognosis and tumor proliferative activity by Ki-67 staining or DNA ploidy pattern using an image cytometer. Expression of p53 was observed in 41.3% of carcinomas. No correlation was found between p53 expression and the depth of invasion, lymph node metastasis or Dukes' stage. No difference in survival was found between p53 positive and negative patients after curative surgery. We also studied the DNA ploidy pattern using an image cytometer in 28 carcinomas. Aneuploidy was found more frequently in the p53 positive areas than in the negative ones, but there was no significant difference. The DNA index showed no difference between the p53 positive and negative areas. We examined proliferating activity using Ki-67. There was no difference in the Ki-67 labeling index between p53 positive and negative areas. In the present study, there was no correlation between p53 expression and pathological findings, prognosis, tumor proliferative activity using Ki-67 staining or DNA ploidy pattern. Thus, p53 expression was suggested to have little relationship to grade of malignancy.