Molecular Imaging of Radiolabeled Bispecific T-Cell Engager 89Zr-AMG211 Targeting CEA-Positive Tumors

Purpose: AMG 211, a bispecific T-cell engager (BiTE) antibody construct, targets carcinoembryonic antigen (CEA) and the CD3 epsilon subunit of the human T-cell receptor. AMG 211 was labeled with zirconium-89 (⁸⁹Zr) or fluorescent dye to evaluate the tumor-targeting properties.Experimental Design: ⁸⁹Zr-AMG211 was administered to mice bearing CEA-positive xenograft tumors of LS174T colorectal adenocarcinoma or BT474 breast cancer cells, as well as CEA-negative HL-60 promyelocytic leukemia xenografts. Biodistribution studies with 2- to 10-μg ⁸⁹Zr-AMG211 supplemented with unlabeled AMG 211 up to 500-μg protein dose were performed. A BiTE that does not bind CEA, ⁸⁹Zr-Mec14, served as a negative control. ⁸⁹Zr-AMG211 integrity was determined in tumor lysates ex vivo Intratumoral distribution was studied with IRDye800CW-AMG211. Moreover, ⁸⁹Zr-AMG211 was manufactured according to Good Manufacturing Practice (GMP) guidelines for clinical trial NCT02760199Results: ⁸⁹Zr-AMG211 demonstrated dose-dependent tumor uptake at 6 hours. The highest tumor uptake was observed with a 2-μg dose, and the lowest tumor uptake was observed with a 500-μg dose. After 24 hours, higher uptake of 10-μg ⁸⁹Zr-AMG211 occurred in CEA-positive xenografts, compared with CEA-negative xenografts. Although the blood half-life of ⁸⁹Zr-AMG211 was approximately 1 hour, tumor retention persisted for at least 24 hours. ⁸⁹Zr-Mec14 showed no tumor accumulation beyond background level. Ex vivo autoradiography revealed time-dependent disintegration of ⁸⁹Zr-AMG211. 800CW-AMG211 was specifically localized in CEA-expressing viable tumor tissue. GMP-manufactured ⁸⁹Zr-AMG211 fulfilled release specifications.Conclusions: ⁸⁹Zr-AMG211 showed dose-dependent CEA-specific tumor targeting and localization in viable tumor tissue. Our data enabled its use to clinically evaluate AMG 211 in vivo behavior. Clin Cancer Res; 24(20); 4988-96. ©2018 AACR.

Biodistribution and PET Imaging of Labeled Bispecific T Cell-Engaging Antibody Targeting EpCAM

AMG 110, a bispecific T cell engager (BiTE) antibody construct, induces T cell-mediated cancer cell death by cross-linking epithelial cell adhesion molecule (EpCAM) on tumor cells with a cluster of differentiation 3 ε (CD3ε) on T cells. We labeled AMG 110 with (89)Zr or near-infrared fluorescent dye (IRDye) 800CW to study its tumor targeting and tissue distribution.

METHODS

Biodistribution and tumor uptake of (89)Zr-AMG 110 was studied up to 6 d after intravenous administration to nude BALB/c mice bearing high EpCAM-expressing HT-29 colorectal cancer xenografts. Tumor uptake of (89)Zr-AMG 110 was compared with uptake in head and neck squamous cell cancer FaDu (intermediate EpCAM) and promyelocytic leukemia HL60 (EpCAM-negative) xenografts. Intratumoral distribution in HT-29 tumors was studied using 800CW-AMG 110.

RESULTS

Tumor uptake of (89)Zr-AMG 110 can be clearly visualized using small-animal PET imaging up to 72 h after injection. The highest tumor uptake of (89)Zr-AMG 110 at the 40-μg dose level was observed at 6 and 24 h (respectively, 5.35 ± 0.22 and 5.30 ± 0.20 percentage injected dose per gram; n = 3 and 4). Tumor uptake of (89)Zr-AMG 110 was EpCAM-specific and correlated with EpCAM expression. 800CW-AMG 110 accumulated at the tumor cell surface in viable EpCAM-expressing tumor tissue.

CONCLUSION

PET and fluorescent imaging provided real-time information about AMG 110 distribution and tumor uptake in vivo. Our data support using (89)Zr and IRDye 800CW to evaluate tumor and tissue uptake kinetics of bispecific T cell engager antibody constructs in preclinical and clinical settings.

Neutron-proton asymmetry dependence of spectroscopic factors in ar isotopes

Spectroscopic factors have been extracted for proton-rich 34Ar and neutron-rich 46Ar using the (p, d) neutron transfer reaction. The experimental results show little reduction of the ground state neutron spectroscopic factor of the proton-rich nucleus 34Ar compared to that of 46Ar. The results suggest that correlations, which generally reduce such spectroscopic factors, do not depend strongly on the neutron-proton asymmetry of the nucleus in this isotopic region as was reported in knockout reactions. The present results are consistent with results from systematic studies of transfer reactions but inconsistent with the trends observed in knockout reaction measurements.

Predictors of high-dose antipsychotic prescription in psychiatric patients in Hong Kong

OBJECTIVE

To determine the factors associated with high-dose antipsychotic prescribing for psychiatric patients in Hong Kong.

DESIGN

Retrospective cross-sectional study.

SETTING

Psychiatric in-patients and out-patients in the New Territories West Cluster, Hong Kong.

PATIENTS

A total of 1129 in-patients and 7520 out-patients who received antipsychotic medications on the study date.

MAIN OUTCOME MEASURES

Demographic and clinical data were compared for patients receiving 'normal' and high dosages of antipsychotic medications.

RESULTS

High dosages were prescribed for 104 (9.2%) of the in-patients and 137 (1.8%) of out-patients. Antipsychotic polypharmacy was the most powerful predictor of high-dose prescribing, with an odds ratio of 8.88 for in-patients and 10.82 for out-patients.

CONCLUSION

Antipsychotic polypharmacy was the main determinant of high-dose antipsychotic prescribing in this study. Further studies should be conducted to look for other variables contributing to such prescribing in Hong Kong.

The components of executive functioning in a cohort of patients with chronic schizophrenia: a multiple single-case study design

We examined the fractionation of executive functioning performance in ninety patients with schizophrenia, who were tested for initiation, sustained attention, switching/flexibility, attention allocation and impulsivity/disinhibition. The participants were also given tests of general intelligence and memory. We analysed the executive functioning performance of individual patients against normative data from our laboratory, and summary scores for all of the executive functioning components were computed. For each component, participants were classified as having impairment with a test performance of 1.5 standard deviations or more from the norm of the corresponding test. Of all of the participants, 27.8% (n=25) demonstrated poor performance in all of the components, and 5.6 % (n=5) exhibited intact or fair performance in all of the components. Furthermore, 18.9% (n=17) showed intact or fair performance in one component, 16.7% (n=15) in two components, 21.1% (n=19) in three components and 10% (n=9) in four components. The groups did not differ in education, gender or duration of illness, but the group that showed impaired performance in all of the components demonstrated the most severe psychotic symptoms after controlling for background intelligence, age and medication. The differential breakdown for the executive functioning performance across the participants suggests that the fractionation of central executive functioning occurs in schizophrenia.

The Significance of Hepatic Vein Outflow Volume in Hepatic Outflow Insufficiency of Living Right Liver Graft Evaluated by Doppler Ultrasound

The color Doppler ultrasound has been used to evaluate hepatic vein (HV) outflow insufficiency based on flow velocity and waveforms. In our experience, some cases with flat waveforms are clinically asymptomatic. The parameters of HV flow velocity and waveforms are not always correlated with clinical problems. So, we proposed that total HV flow volume (HVFV) may be a more reliable index. From August 2001 to July 2003, 31 cases among 48 adult-to-adult living related transplants of a right liver graft had one HV anastomosis. HV velocity, waveforms, and HVFV were compared both before and after transplantation. We set the minimal HVFV ratio at 80% based on the original HVFV before graft retrieval. There was no significant difference in HVFV before liver graft retrieval between the 2 groups, but there was a significant change after transplantation. There were no cases of HV insufficiency among group A patients (>80%), whose HVFV ranged from 397 to 1181 mL/min with ratios from 75% to 180% (mean 115%). In group B, there were 4 complicated cases with prolonged severe ascites (<80%) with HVFV ratios from 56% to 76% (mean 66%). Fisher exact test showed a great significance (P < .001). Thus the preliminary criteria of 80% minimal HVFV ratio allows detection of HV insufficiency for further interventional management.

Soluble type II transforming growth factor-beta receptor inhibits established murine malignant mesothelioma tumor growth by augmenting host antitumor immunity

PURPOSE

Transforming growth factor (TGF)-beta blockade has been proposed as an anticancer therapy; however, understanding which tumor patients might benefit most from such therapy is crucial. An ideal target of such inhibitory therapy might be malignant mesothelioma (MM), a highly lethal, treatment-resistant malignancy of mesothelial cells of the pleura and peritoneum that produces large amounts of TGF-beta. The purpose of this study was to explore the possible therapeutic utility of TGF-beta blockade on MM.

EXPERIMENTAL DESIGN

To evaluate this hypothesis, we tested the effects of a soluble TGF-beta type II receptor (sTGF-beta R) that specifically inhibits TGF-beta1 and TGF-beta 3 in three different murine MM tumor models, AB12 and AC29 (which produce large amounts of TGF-beta) and AB1 (which does not produce TGF-beta).

RESULTS

Tumor growth of both established AB12 and AC29 tumors was inhibited by sTGF-beta R. In contrast, AB1 tumors showed little response to sTGF-beta R. The mechanism of these antitumor effects was evaluated and determined to be primarily dependent on immune-mediated responses because (a) the antitumor effects were markedly diminished in severe combined immunodeficient mice or mice depleted of CD8(+) T cells and (b) CD8(+) T cells isolated from spleens of mice treated with sTGF-beta R showed strong antitumor cytolytic effects, whereas CD8(+) T cells isolated from spleens of tumor-bearing mice treated with of control IgG2a showed no antitumor cytolytic effects.

CONCLUSIONS

Our data suggest that TGF-beta blockade of established TGF-beta-secreting MM should be explored as a promising strategy to treat patients with MM and other tumors that produce TGF-beta.

Executive dysfunctions in schizophrenia. Relationships to clinical manifestation

Studies suggest that executive functions in patients with schizophrenia are markedly impaired as compared with normal controls. Most previous studies employed tests of executive functions adopted from frontal lobe neuropsychological paradigms based on lesion studies. This study employed several more recently developed theory-driven tests of executive functions addressing the construct of the supervisory attentional system. We explore the pattern of executive function impairment using factor analysis and subsequently investigate the relationships between these executive function factors and the clinical features in a sample of chronic schizophrenic patients. A total of 51 patients with chronic schizophrenia were recruited. The Sustained Attention Response to Task (SART), Six Elements Test (SET) and Hayling Sentence Completion Test (HSC) were used to assess executive functions. Three factors were identified within the executive function tests: 1) The "semantic inhibition factor" comprised items in the HSC, 2) the "action/attention inhibition" factor comprised the SART commission error and the SET rule-breaking score and 3) the "output generation factor" comprised the SET raw score and the correct SART response. Significant relationships were found between these derived factors and clinical features after partialling out the confounding effect of age, education and illness duration. The three theory-based tests of executive function were shown to have good construct validity among the group of chronic schizophrenic patients.

Problem-solving ability in chronic schizophrenia. A comparison study of patients with traumatic brain injury

We tested the hypothesis that patients with schizophrenia are more prone to impairment in planning and problem-solving as compared with normal controls and patients with traumatic brain injury (TBI) by administering the Tower of Hanoi (TOH) task. A total of one hundred and fifty-three participants (51 in each group) were recruited. The performance of the patient groups was markedly worse than normal controls in terms of profile score, number of rule-breaking behaviour, and mean execution time. Two-way 3 (group) x 6 (complexity) ANOVAs indicated that significant main effects of group and complexity were observed in the number of moves, planning time to initiate the first move and subsequent execution time. The general performance of TOH in the schizophrenia group was very similar to that of the TBI group. Subsequent comparison of sub-groups of frontal and posterior lobe damage indicated the pattern of performance in schizophrenia patients lie between them. Taken together, these findings suggest that neither focal frontal nor temporal lobe damage is a sufficient explanation for the problem-solving deficits in patients with schizophrenia.

A Study of Sensitivity of the Sustained Attention to Response Task in Patients With Schizophrenia

The sustained attention to response task (SART), a measure of sustained attention created by Robertson, Manly, Andrade, Baddeley, and Yiend (1997), was administered to 51 patients with schizophrenia and 51 normal controls to provide information on the sensitivity of the measure in this clinical group. Patients with schizophrenia performed significantly worse than the normal controls in correct response, reaction time for correct response, and efficiency estimate of taking account of both the accuracy and speed of movement. Moreover, the patient group was more often correctly classified as defective on the basis of efficiency estimate than the normal controls. These data provide further evidence of the sensitivity of the SART to patients with schizophrenia.

Single imaging modality evaluation of living donors in liver transplantation: magnetic resonance imaging

BACKGROUND

Liver graft size, anatomy of the bile duct and the vascular inflow and outflow are essential for living related liver transplantation (LRLT). Preoperative delineation of those variations that would change the operative procedure to achieve a successful result especially in an emergency condition.

PURPOSE

Our aim was to develop a rapid and noninvasive imaging diagnostic method for the detection of anatomical variants that is mandatory for a safe operation when selecting potential liver transplant living donors. We used a different magnetic resonance (MR) imaging technique, which enabled to us to exploit the anatomical landmark of the liver, signal enhancement of blood flow in the abdomen, and the intrahepatic biliary routes inside the liver. Then, with the help of Advantage Window workstation reconstruction, the reconstructed single vascular or biliary systems were displaced in a three-dimensional fashion and the whole examination finished within 30 min.

METHODS

Modification of the standard MR technique was performed on a superconductive 1.5T whole body image scanner, MR arteriogaphy, venography, and cholangiography with three-dimensional reconstruction in evaluating the anatomy of the hepatic arteries, hepatic veins, portal venous system, bile ducts, and liver size in potential liver transplant living donors. These anatomical structures were compared with traditional imaging methods.

RESULTS

In all 38 cases, as well as delineation of the portal vein detail to the segmental level was satisfactorily obtained in this MR study. The images were well displayed in a three-dimensional fashion, which had good correlation with images from traditional imaging modalities and operative findings. In 86.8% cases, the MR arteriography was well matched with the celiac angiography. Of those 17 operative cases, estimation of liver volume was well correlated with the liver graft within 3.9-12.5% variation. In the major hepatic vein, we obtained 100% accuracy and 88.2% in the minor branches. Of 12 donors received intraoperative cholangiography during liver donation, good correlation of biliary anatomy was achieved. One donor was excluded from graft donation due to the complicated arterial supply to the left liver. According to the anatomical variation, surgical procedures in graft harvesting and anastomosis were readjusted and no major complications were found in those donors and all recipients survived after liver transplantation.

CONCLUSION

MR volumetry, venography, angiography, and cholangiography with three-dimensional reconstruction is sufficient for all major imaging evaluation. It may replace the traditional conventional catheter angiography, computed tomography, sonography and endoscopic retrograde cholangiography as a single investigation in the evaluation of the potential liver transplant donors. Angiography is only valuable in suboptimal cases and intraoperative cholangiography is only performed in biliary ductile variants.

Interventional radiologic procedures in liver transplantation

Postoperative biliary and vascular complications contribute significantly to morbidity and mortality in liver transplantation. Interventional radiologists are an integral part of the multidisciplinary team necessary for optimizing the management of these complications. During a 15-year period, 39 cadaveric and 25 living related liver transplantations were performed at the Chang Gung Memorial hospital, Taiwan. Of 64 liver transplant recipients, 9 (3 adult and 6 pediatric) underwent 13 interventional radiological procedures for the treatment of biliary sludge-casts (n = 2), bile duct occlusion or stenosis (n = 2), hepatic veins thrombosis (n = 1), hepatic veins stenosis (n = 1), portal vein stenosis with splenorenal shunting (n = 1), biloma (n = 1), and infected fluid collection or ascites (n = 4). Antegrade or retrograde interventional approach was used to successfully treat all biliary complications, and all percutaneous drainage procedures were effective in the control of intra-abdominal fluid collections. Portal vein stenosis was treated by balloon dilatation, and the associated splenorenal shunt was closed by metallic coil embolization via transhepatic catheterization of the portal vein. Hepatic vein stenosis was effectively treated by balloon dilatation and expandable metallic stent deployment via transfemoral and jugular venous approaches, respectively. Hepatic vein thrombosis was only partially lysed by transvenous streptokinase administration, and surgical thrombectomy was needed to achieve complete recanalization. The total success rate of the interventional procedures was 92 % with no procedure-related complications. The overall survival rate in this series is 89 %, and all patients who underwent living related liver transplantation maintain to date a 100 % survival rate. We can conclude that interventional radiological procedures are very useful for managing biliary and vascular complications after liver transplantation. These techniques provide a cure in most situations, thus obviating the need for further surgical intervention or re-transplantation.

Biliary complications in living related liver transplantation

BACKGROUND

Biliary tract reconstruction has long been considered the Achilles' heel of liver transplantation as biliary complications can increase morbidity and mortality especially in partial liver graft transplantation.

METHODS

Thirty-four living related liver transplants were performed at Chang Gung Memorial Hospital in Kaohsiung for 33 children and 1 adolescent during a 5.5-year period. All potential donors underwent a detailed preoperative imaging study of the vascular and biliary anatomy, including three-dimensional helical computed tomographic cholangiography (n = 20), magnetic resonance cholangiography (n = 14), and intra-operative cholangiography (n = 31) before graft retrieval. All hepatic artery anastomoses were performed in the standard microsurgery fashion and their patency was confirmed intra-operatively using Doppler ultrasound.

RESULTS

The biliary complication rate was 8.8% (3/34), including multiple intrahepatic biliary stenosis of unknown origin (n = 1), bile leakage from the Roux-en-Y loop (n = 1), and a missed biliary radicle (n = 1) which were treated via interventional radiological and surgical procedures. The overall graft and patient survival rates were 100%.

CONCLUSION

The biliary complication rate in this series was low compared to those of other experienced centers. Complete study of the variations of intrahepatic duct ramification pre-and-intra-operatively provided adequate information on the appropriate transection plane. Furthermore, intra-operative Doppler ultrasound verification of vessel patency helps prevent vascular complications, which has been identified as a cause of biliary complications.

Outflow tract reconstruction in living donor liver transplantation

BACKGROUND

Hepatic venous reconstruction is critical in living donor liver transplantation because outflow obstruction may lead to graft dysfunction or loss. We describe our experience and analyze outcomes with a technique of creating a single outflow tract using venoplasties of the graft and recipient hepatic veins.

PATIENTS AND METHODS

A retrospective study was done on 38 consecutive living donor liver transplants performed from June 1994 to March 2000. The grafts included 36 left-side grafts and 2 right-side grafts. Nine grafts had multiple hepatic veins and required a venoplasty of two or three hepatic veins to create a single outflow orifice. Triple recipient hepatic venoplasty was performed in 32 patients, double venoplasty in 5 and none in 1.

RESULTS

There were four cases of outflow obstruction, three occurring in patients with a double recipient venoplasty. Two of the problems were remedied intraoperatively by adjusting the position of the graft although two were structural in nature and required the insertion of expandable metallic vascular stents. All donors and recipients with their original grafts are alive at a mean follow-up period of 27 months.

CONCLUSION

A triple recipient venoplasty with a matching venoplasty of multiple graft hepatic veins to create a single wide outflow orifice is recommended in living donor liver transplantation using left side grafts.

Aspiration in transtracheal oxygen insufflation with different insufflation flow rates during cardiopulmonary resuscitation in dogs

We investigated whether transtracheal insufflation of oxygen with different insufflation flow rates protects against aspiration of gastric contents during cardiopulmonary resuscitation (CPR). Its ventilation and oxygenation effects were also evaluated. Cardiac arrest was induced in anesthetized and paralyzed 18 mongrel dogs. Chest compression using an automatic thumper was performed while the dogs randomly received no mechanical ventilation (Group I, n = 6) or were transtracheally insufflated with 4 L/min oxygen (Group II, n = 6) or 10 L/min oxygen (Group III, n = 6). Blood samples were drawn every 5 min for 20 min for blood gas analysis. the mouths of the dogs were then filled with 70 mL mixed barium, and 10 min after chest compression, chest radiographs were taken to evaluate the incidence of pulmonary aspiration. Results showed that pulmonary aspiration occurred in all dogs of Group I and three of the six dogs in Group II, whereas dogs in Group III were free from pulmonary aspiration. Both transtracheal oxygen insufflation groups maintained oxygen saturation significantly better than Group I, but mild hypercapnia was observed in all groups after 20 min of CPR. We conclude that transtracheal oxygen insufflation, but not chest compression alone, was able to maintain oxygenation for 20 min during CPR in dogs with cardiac arrest. Mild hypercapnia was noted in all groups. Chest compression alone caused pulmonary aspiration, whereas insufflation of 10 L O(2)/min provided better protection against pulmonary aspiration than that of 4 L O(2)/min.

International sharing of split liver grafts in Asia: initial experience

The donor shortage problem is particularly serious in Asia and has markedly limited progress in liver transplantation. The increasing demand has, in fact, made it necessary to resort to living donor liver transplantation in both pediatric and adult recipients. Nevertheless, expanding the use of split liver allografts is yet another option to increase the supply. This has a wide potential application on a regional level because most liver transplant programs are still small and may have limited resources in terms of being able to do two transplants in one sitting. The first experience of overseas sharing of split liver grafts in Asia took place in January 1999. The graft was from a 35-yr-old donor from Kaohsiung, Taiwan, who sustained irreversible brain damage in a vehicular accident and had optimal conditions for multiorgan donation. The liver was split ex vivo and the left lateral segment was given to a 3-yr-old girl with biliary atresia at the Chang Gung Memorial Hospital. The extended right lobe split graft was transported to Hong Kong and transplanted into a 51-yr-old male patient with end-stage hepatitis C cirrhosis who was then in a state of acute failure with hepatorenal syndrome. Graft function was excellent in both recipients and the patient from Taiwan was discharged without any complications. Unfortunately, the Hong Kong recipient developed a cerebrovascular accident and required a reoperation for bile leakage from the cut surface of the liver in the early postoperative period. He has made a steady recovery since then; graft function has remained good and his kidneys have recovered. Both patients are currently alive and well 11 months post-transplant. This initial experience of overseas sharing of split liver grafts in Asia demonstrates its feasibility. It has a potentially wide applicability and could lead to the establishment of a formal organ-sharing network in the region. Established competence and mutual trust among the participating liver transplant teams would be essential in perpetuating such a graft-multiplying strategy on an organized basis.

Aspiration in chest compression alone without mechanical ventilation in the head down position in dogs

BACKGROUND

Previous work by the authors has shown that chest compressions alone without mechanical ventilation during cardiopulmonary resuscitation in the natural supine position was associated with pulmonary aspiration in dogs. The purpose of this investigation was to test the hypothesis that a head down position may prevent aspiration during chest compressions alone and whether oxygenation can be improved by simply insufflation of oral oxygen 10 min after cardiac arrest.

METHODS

Cardiac arrest was induced in ten mongrel dogs which were anesthetized and paralysed. Eight underwent chest compressions alone in different head down positions using an automatic compressor at 9 kg compression force and 3 cm compression depth. The study was composed of two parts. Part 1 evaluated the effect of insufflation of 10 l/min O2, into the mouth of the dogs, 10 min after initiation of resuscitation, using chest compressions alone. Part 2 was designed to test our hypothesis that the head down position may protect the lungs from aspiration during chest compression alone. The mouths of the dogs were filled with mixed barium and the dogs underwent serial episodes of chest compressions, for 10 min each, in the 20 degree head down, 10 degree head down and the natural supine positions. Chest X-rays with antero-posterior and lateral views were taken to evaluate pulmonary aspiration. Two additional dogs underwent direct chest compression alone in the natural supine position and the time of chest compression was shortened to 5 min.

RESULTS

All dogs in the natural position showed evidence of pulmonary aspiration of barium, five or six of the dogs showed tracheal aspiration in the 10 degree head down position, while no any barium was visualized in the tracheo-broncheal trees of the dogs in the 20 degree head down position. Supplemental oxygen in the mouth improved the mean PaO2 from 67 +/- 26 to 160 +/- 97 mmHg during chest compressions alone.

CONCLUSION

Chest compression alone without mechanical ventilation in the supine position caused pulmonary aspiration in the unprotected airway in dogs. This complication could be prevented by adopting a 20 degree head down position. The 10 degree head down position seemed to reduce the severity of the pulmonary aspiration, but not enough to eliminate the danger altogether. Supplemental oxygen in the mouth can improve oxygenation in chest compressions alone.

Minimal blood loss living donor hepatectomy

BACKGROUND

Donor hepatectomy with maximal safety while preserving graft viability is of principal concern in living donor liver transplantation. There are compelling reasons for avoiding blood transfusion, even with autologous blood, to avoid the potential risks it imposes on healthy donors. This study aims to describe the surgical technique and clinical outcomes of living donor hepatectomy with minimal blood loss requiring no blood transfusion.

METHODS

Donor hepatectomy was performed in 30 living donors according to a detailed preoperative imaging study of the vascular and biliary anatomy. Liver parenchymal transection was carried out with strict adherence to a meticulous surgical technique without vascular inflow occlusion to either side of the liver. Pre-, intra-, and postoperative data were gathered, and factors related to blood loss were analyzed retrospectively.

RESULTS

The intraoperative blood loss ranged from 20 to 300 ml with a mean of 72.0+/-58.9 ml (median, 55 ml), and neither homologous nor autologous blood transfusion was required in any of the donors intra- and postoperatively. All 30 donors were discharged with minimal complications, and remain well at a mean follow-up of 24 months after donation. Excellent graft viability was verified by the fact that all 30 recipients are alive and well with a few manageable complications. The actual graft and patient survival are both 100% at the time of writing.

CONCLUSIONS

Regardless of the extent of donor hepatectomy, blood loss can and should be kept to a minimum, and living donor hepatectomy without blood transfusion is a realistic objective.

Repeated hypotensive episodes due to hepatic outflow obstruction during liver transplantation in adult patients

We report two cases of unusual repeated hypotension, decreased cardiac output, decreased mixed venous oxygen saturation, decreased central venous pressure, pulmonary artery pressure, and pulmonary wedge pressure after the completion of all vascular anastamoses of liver transplantation. These unstable hemodynamics appear to reflect a clinically relevant picture of hypovolemia. However, the real cause was partial hepatic outflow obstruction. The obstruction was suspected because hypotension was alleviated by elevating the full-sized liver graft ventrally and to the left. Doppler ultrasound examination confirmed that the flow velocity of the hepatic vein outflow was insufficient when the liver fell to its resting position in the right hepatic fossa. An additional side-to-side cavo-caval anastomosis resolved the problem in one patient, whereas the other required not only the additional anastomosis, but also application of a tissue expander filled with 770 mL normal saline beneath the liver to eliminate the obstruction. We emphasize that obstruction of the hepatic outflow causes only temporal hypovolemia because of a decrease of venous return and that treatment of this complication should be surgical intervention to relieve the obstruction. Blind resuscitation with fluids will not solve the problem and, in fact, may result in fluid overload with subsequent complications.

Magnetic resonance of the hepatic veins with angular reconstruction: application in living-related liver transplantation

BACKGROUND

Preoperative mapping of the hepatic venous system of the partial liver graft is indispensable to the success of living-related liver transplantation. We assessed the accuracy of magnetic resonance (MR) venography with angular reconstruction in depicting the tributaries of the middle hepatic vein and left hepatic vein in the donors, which was essential in graft retrieval and venoplasty.

METHODS

Nineteen living-related liver transplantation donors underwent a pretransplantation survey, including sonography and MRI for hepatic venous evaluation. T1-weighted images were reconstructed manually, using the inferior vena cava as a fixed point for tilting to produce an oblique plane image where both the middle hepatic vein and left hepatic vein could be demonstrated draining into the inferior vena cava. The reconstructed images of the hepatic veins were compared with preoperative sonography, intraoperative sonography, and operative findings.

RESULTS

Preoperative sonography and MR findings correlated well with the operative findings in the major hepatic veins. The MR venography of the ramification of the hepatic veins has an accuracy of 93%, the sonography, 84%. Sonography is slightly inferior in the evaluation of the hepatic vein in segment 4 and the left superior hepatic vein, with an accuracy of 73% and 67%, respectively.

CONCLUSION

MR venography with angular reconstruction is accurate in depicting the complex distribution of the hepatic veins of the left liver, providing important information for decision making as to the cutting plane during graft retrieval and the method of venoplasty and anastomosis. Thus, unnecessary blood loss could be avoided and vascular complications could be prevented, as these conditions would be unacceptable for a healthy living donor. We propose that MR venography, a rapid and reliable technique, is an appropriate alternative examination or complementary modality to sonography in the pretransplantation evaluation of the living donor.

Aspiration and transtracheal jet ventilation with different pressures and depths of chest compression

OBJECTIVE

To evaluate aspiration prophylaxis during cardiopulmonary resuscitation (CPR) using transtracheal jet ventilation (TJV) with different pressure-depths of chest compression and chest compression alone without mechanical ventilation.

DESIGN

Prospective, animal study.

SETTING

Animal research laboratory, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Taiwan.

SUBJECTS

Mongrel dogs (n = 10) weighing 8 to 12 kg.

INTERVENTIONS

Eight mongrel dogs were anesthetized, paralyzed, and ventilated transtracheally with a jet ventilator at frequencies varied from 600 to 10 cycles/min. The airway pressures below and above the jetting port were measured. The mouth of the dog was filled with barium and chest radiographs were taken 10 mins after chest compression with 20-pound pressure and 5-cm depth in group 1 and 10-pound pressure and 3-cm depth in group 2 at each different jet frequency. Two additional dogs underwent the same procedures but received only chest compression without TJV.

MEASUREMENTS AND MAIN RESULTS

Pulmonary aspiration was not noted in the chest radiographs from either group. The airway pressure changes between groups were not significantly affected by difference in pressures and depths of chest compression at the same jetting frequency. However, pulmonary aspiration occurred in the two dogs that received chest compression alone without TJV.

CONCLUSIONS

Application of TJV during chest compression with different pressures and depths caused no pulmonary aspiration in dogs at frequencies between 600 and 10 cycles/min. The protection against aspiration disappeared if the dogs received only chest compression without TJV. The mechanism of preventing pulmonary aspiration in TJV is thought to be due to forceful unidirectional gas outflow through the larynx and higher airway pressure in the carina than in the upper airway. The airway pressures were not affected by different chest compression pressures and depths because the larynx stayed open during TJV and the air outflow could freely move out without increasing the pressure in the airway.

Post-transplant changes of segment 4 after living related liver transplantation

The purpose of this study was to evaluate the outcome of the medial segment of the graft after living related liver transplantation (LRLT). Of the 12 pediatric recipients who underwent LRLT, 2 received whole left liver graft, 1 left lateral segment graft, and 9 extended left lateral segment grafts. The hepatic veins of the donor were reviewed and the volume of the medial segment and left lateral liver was measured before and 6 months after liver transplantation. The flow velocity and direction of the portal vein in the medial segment graft was also evaluated by Doppler ultrasound. The grafted livers of all recipients showed a substantial increase in volume of 9-120% 6 months after LRLT. For the left lateral segment, an increase in volume was found in all cases ranging from 21 to 245%. For the medial segment, volume increases of 5-48% were found in seven cases with normal hepatopetal flow detected inside the segment 4 intrahepatic portal vein. In four cases, the partial medial segment graft of the extended left lateral liver graft decreased in volume from 33 to 69%. Among these four cases, slow flow (n = 2) and hepatofugal flow (n = 1) were also detected in the intrahepatic portal vein of the medial segment. Mapping of the tributary of the hepatic veins of the graft revealed inadequate venous drainage of the partial segment 4 graft, which may be considered as the cause of the atrophic change of the partial segment 4 graft. In conclusion, different regenerative rates between the left lateral segment and the medial segment were noted, with a greater rate in the left lateral segment. The venous drainage of the medial segment is of primary concern in the determination of the outcome of the regeneration. Atrophic change occurs when inadequate hepatic venous drainage is encountered. Therefore, if an extended left lateral liver graft is required, the corresponding draining veins of the partial medial segment must be preserved. Otherwise, whole left liver or left lateral segment graft would be a better choice.

Intraoperative Doppler ultrasound in liver transplantation

The purpose of this study was to determine the utility of intraoperative Doppler ultrasound for the diagnosis and reduction of the vascular complications in liver transplantation. This study included 19 pediatric and 5 adult patients. In the pediatric group, 12 patients received living related liver transplantation (LRLT), two splitting liver transplantation (SLT), three reduced-size liver transplantation (RLT) and two full-size pediatric liver transplants (FPLT). The hemodynamics and waveform of the hepatic vein, portal vein and hepatic artery were evaluated by intraoperative Doppler ultrasound (US) after reperfusion of the graft. Unsatisfactory hemodynamics was identified in nine cases, including decrease hepatic venous flow (6-9 cm/s) with non-pulsative flat waveform (adults, n = 2 and LRLT, n = 2); portal vein thrombosis (LRLT, n = 1); decrease portal flow (8 mL/min/kg) (LRLT, n = 1); occlusion of the portal vein (SLT, n = 1); poor arterial flow with dampened artery waveform (FPLT, n = 2). These abnormalities were all successfully re-reconstructed by surgical procedures and achieved a graft survival rate of 100%. Two late vascular complications including hepatic venous thrombosis and recurrent portal vein stenosis with splenorenal shunt were discovered 1 month later. They were treated effectively by surgical thrombolectomy and percutaneous balloon dilatation and metallic coils embolization respectively. Three patients died of non-vascular complications and all patients who underwent LRLT survived with a resultant 87.5% overall survival rate. In conclusion, intraoperative Doppler US is efficient in detecting abnormal hepatic hemodynamics, which permits early intervention and hence a better prognosis for the patients. Re-reconstructive procedures were monitored closely under Doppler US guidance until proper flow and wave-form were established. This reduces post-transplant vascular complications and thereby eliminates the likelihood of a lethal complication that might call for re-transplantation.

A survey of antipsychotic treatment for schizophrenia in Hong Kong

OBJECTIVE

To obtain information on prescription pattern of antipsychotic drugs for schizophrenic in-patients treated in public hospitals in Hong Kong. Four main areas of antipsychotic treatment are reported in this paper: (1) doses of antipsychotic drugs, (2) the practice of giving multiple antipsychotic agents simultaneously, (3) use of antipsychotics in divided daily doses and (4) co-administration of antipsychotic and antiparkinson drugs.

METHODS

A cross-sectional survey of prescriptions of antipsychotic medication for a representative sample of 957 schizophrenic in-patients was conducted on a randomly chosen census day. Questionnaire items included basic demographic and clinical data, as well as inventory for all medications received by patients on census day.

RESULTS

The mean antipsychotic dose was 854 +/- 759 (median: 600; range) 0-4450) mg CPZeq. Over two-third of the patients were given more than drug concurrently while less than 20% received the medication in multiple divided doses. Antiparkinson drugs were prescribed with antipsychotic medication in 69.61%, of the subjects. There were few differences between acute and chronic patients with respect to their respective prescription patterns.

CONCLUSIONS

Antipsychotic treatment of schizophrenic inpatients in Hong Kong is largely in accord with international standards. Problematic areas identified for closer scrutiny include the concurrent use of more than one antipsychotic drug for both acute and chronic patients, and the higher than recommended doses for antipsychotic drugs and frequent use of antiparkinson medication for chronic patients. Dissemination of these results, accompanied by continuing medical education about psychopharmacology, are planned to further improve the quality of treatment for schizophrenic patients.

Histopathology of the liver in pediatric patients following transplantation

Recognition of rejection and other hepatic complications by needle biopsy plays a significant role in the management of liver allograft recipients. In this report, 22 pediatric patients (below 18 years old) were selected from the 37 liver transplants. Seven of the 22 cases have an uneventful posttransplant course. The most common cause of allograft injury in these patients appeared to be acute cellular rejection. It occurred in 7 (31.8%) of the 22 cases and was the primary process in 8 of the 25 episodes of liver dysfunction. Other etiologies, such as opportunistic viral infection (3 cases), biliary obstruction (2 cases), preservation injury (1 case), and vascular obstruction (1 case) were less common. Acute graft rejection causing liver dysfunction was associated with a mixed portal inflammation, destruction of the interlobular bile ducts, and varied degree of venous endotheliitis, followed by centrilobular hepatocyte necrosis. Chronic rejection was not seen in our pediatric cases. Cold ischemic injury causing transient graft dysfunction as seen in one of our patients demonstrated focal, limited areas of hepatocyte necrosis, mild centrilobular hepatocyte ballooning, and cholestasis without evidence of bile duct damage. More severe ischemic injury resulted from vascular complication causing diffuse hepatocyte necrosis was seen in one patient with hepatic vein thrombosis. The histologic patterns observed were not pathognomic; however, liver biopsies were helpful in suggesting the probable cause of liver dysfunction and in predicting subsequent allograft recovery when used in conjunction with clinical information, radiologic, and other laboratory tests.

Imaging in pediatric liver transplantation

In liver transplantation, the role of the imaging study in the evaluation of transplant candidacy is to define the conditions in which transplantation is contraindicated and to identify anatomic variations that may alter the surgical approach. Among pediatric recipients, the largest numbers of patients were suffering from biliary atresia, and metabolic diseases. Acquired and congenital vascular anomalies are usually associated with biliary atresia which may be hazardous to liver transplantation requiring a modification of standard surgical procedure. Therefore, confirmation of the patency of the vascular structure is the most essential prerequisite especially in living related liver transplantation. From June 17, 1994 to November 30, 1996, eleven living related liver transplantations were performed at Chang Gung Memorial Hospital, Kaohsiung Medical Center. The left liver or the left lateral segment of the liver was used as the graft. It is necessary to keep patency of the inflow and outflow of hepatic vessels and biliary trees of both donor and recipient. Both resected and remnant livers have to function well postoperatively. In order to achieve parenchyma dissection with minimal hepatic damage, various anatomical variations of the liver size, portal vein, hepatic veins and bile duct of the donor cannot be ignored. Therefore, the precise preoperative anatomical evaluation of the donor using various imaging modalities is mandatory for the safe partial liver transplantation. Ultrasound, computed tomography, magnetic resonance image and three dimensional computed tomographic cholangiography are the method of choice in demonstrating the anatomical structures. After the complex anatomical factors can be well evaluated we can assess the appropriateness and feasibility of the procedure that may correct problems during or after transplantation. Finally, noninvasive and safe examination procedures are our outmost concern and policy in doing this survey.

Community psychiatry in Hong Kong

Community psychiatry is well developed in many western countries. However, this psychiatric subspecialty has only recently been officially recognized and established in Hong Kong. This article describes the development and current scope of services. It illustrates how local psychiatrists have met the challenge of adopting a western service model to suit the local Chinese population, with its different socio-cultural value system.

Osteopontin N-terminal domain contains a cryptic adhesive sequence recognized by alpha9beta1 integrin

Osteopontin is an adhesive glycoprotein implicated in numerous diseases associated with inflammation and remodeling. There are several structural domains in osteopontin that are of particular interest. The RGD motif is a cell attachment sequence shown to be critical for cell adhesion through alphav-containing integrins. In close proximity to the RGD domain is the thrombin cleavage site. Previous observations suggest that thrombin cleavage of osteopontin occurs in vivo and may be physiologically important. To study the functional significance of osteopontin cleavage by thrombin, we made glutathione S-transferase-osteopontin fusion proteins. These proteins contain either the N- or C-terminal domains expected to be formed following thrombin cleavage at the Arg169-Ser170 peptide bond. We compared these osteopontin fragments with native osteopontin in their ability to support adhesion of several different cell lines and identified the receptors mediating these interactions. Our data show that the N-terminal osteopontin fragment, which contains the RGD domain, supports adhesion of a melanoma cell line that is unable to bind native osteopontin. This suggests that osteopontin adhesive interactions may be regulated by thrombin cleavage. We also demonstrate that osteopontin contains a cryptic binding activity, which can be recognized by a novel osteopontin receptor. This receptor has been identified as the alpha9beta1 integrin.