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.

P element transformation vectors for studying Drosophila melanogaster oogenesis and early embryogenesis.

We have constructed six new P-element-based Drosophila melanogaster transformation vectors that specifically allow for the high-level accumulation of any RNA of interest in the developing egg and pre-blastoderm embryo. Such specificity results, in part, from the inclusion in the vectors of an enhancer active exclusively in nurse cells, the principal providers of RNA to the egg and early embryo. The nurse cell enhancer was derived from the hsp26 heat-shock (HS) gene, but its activity was neither dependent on nor sensitive to HS. In addition to the nurse cell enhancer, two of the vectors contain sequences from the K10 gene that promote the early transfer of RNAs from nurse cells into the oocyte; RNAs that contain the K10 sequence are transferred into the oocyte during the early to middle stages of oogenesis (i.e., during stages 2-9), while RNAs that lack such sequences are stored in nurse cells until stage 11. All of the vectors contain a tsp and a multiple cloning site (MCS) immediately downstream from the hsp26 nurse cell enhancer. In three of the vectors, the MCS is preceded by an ATG start codon. A wild-type copy of the white gene is included in all of the vectors as a selectable marker for transformation. The specificity of the vectors was demonstrated by the analysis of the expression patterns of lacZ derivatives.

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.

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.

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.

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.

Effect of cyclo-oxygenase inhibitors on Helicobacter pylori susceptibility to metronidazole and clarithromycin.

BACKGROUND: We previously reported that aspirin inhibited Helicobacter pylori growth and suppressed the mutagenic effect of metronidazole. AIM: To determine the effects of a cyclo-oxygenase (COX)-2-specific inhibitor, SC-236, and a non-selective COX inhibitor, indometacin, on the growth, urease activity and antimicrobial susceptibility of H. pylori. METHODS: Three H. pylori reference strains, and 18 clinical isolates were treated with SC-236 or indometacin for 24 and 48 h. Growth, urease activity and susceptibility to clarithromycin and metronidazole of the bacteria were assessed by viable colony counting, spectrophotometry and E-test respectively. RESULTS: SC-236 and indometacin inhibited H. pylori growth in a dose-dependent manner with the lowest inhibitory concentrations of 0.03 and 0.1 mm, and the lethal concentrations of 0.09 and 0.3 mm, respectively. The numbers of CFU/mL in Brucella broth containing 0.09 mm SC-236 were 2 log lower at 24 h, and even 3 log lower at 48 h than that at 0 h (P = 0.035, compared with the vehicle control). Treatment of 0.3 mm indometacin reduced the number of CFU/mL by 1 log at 24 h compared with that at 0 h (P = 0.037 compared with the vehicle control). Helicobacter pylori urease activity began to decrease with 0.06 mm SC-236 at 24 h (P = 0.016), and 0.3 mm indometacin at 48 h (P = 0.025). MICs of metronidazole and clarithromycin against H. pylori were decreased significantly in the presence of 0.03 mm SC-236 or 0.1 mm indometacin (all P < 0.001). CONCLUSION: Both SC-236 and indometacin suppressed the growth and urease activity of H. pylori in a dose-dependent manner, and increased its susceptibility to the antibiotics.

Optimal serological tests for the detection of Helicobacter pylori infection in the Chinese population.

BACKGROUND: Numerous serological tests for the detection of Helicobacter pylori infection have been developed. However, many perform poorly when evaluated in the Chinese population. AIM: To search for optimal serological tests for the detection of H. pylori infection in Chinese patients. METHODS: Consecutive dyspeptic patients referred for upper endoscopy were recruited. During endoscopy, gastric biopsies were taken for the CLOtest and histological examination. Patients were then given a 13C-urea breath test. Sera were used to test for H. pylori infection, employing three commercial enzyme-linked immunosorbent assay kits (pylori DTect, HP IgG and GAP IgG). Results were compared with the gold standard defined by the CLOtest, histology and 13C-urea breath test. RESULTS: Among the 142 patients (47 male, 95 female; mean age, 49 years) recruited, 81 (57%) were H. pylori-positive, 57 (40%) were H. pylori-negative and four (3%) were defined to be indeterminate. Using a self-defined cut-off value after calculation, the best accuracies for the pylori DTect, HP IgG and GAP IgG tests were 97%, 91% and 80%, respectively. CONCLUSIONS: The pylori DTect test is an optimal serological test for the detection of H. pylori infection in Hong Kong Chinese patients. The HP IgG test may be used as an alternative.

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.

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.

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.

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.

Doppler ultrasound evaluation of postoperative portal vein stenosis in adult living donor liver transplantation.

AIM: To evaluate the postoperative portal vein stenosis (PVS) and the diagnostic efficiency of Doppler ultrasound (DUS) in adult living donor liver transplantation (ALDLT). MATERIALS AND METHOD: From January 2007 to December 2008, 103 ALDLTs were performed and postoperatively followed by routine DUS. The morphologic narrowing at the anastomotic site (AS) of the PVS was analyzed. We calculated the PV stenotic ratio (SR) using the following formula: SR (%)=PRE-AS/PRE (PRE=pre-stenotic caliber). An SR>50% was defined as the critical point for PVS. We also calculated the velocity ratio (VR) between the AS and PRE, and set the significant VR as >3:1. Statistical analyses were carried out to determine clinical significance. RESULTS: Using the definition of morphologic PVS by DUS, there were total 20 cases (19.4%) in this series with SR>50%, which included 17 cases with VR>3:1. Eight cases of severe PVS had a stenotic AS>5 mm and subsequently underwent interventional management. Doppler criteria of SR and VR values were elevated up to 75.8% and 7.5:1, respectively, in these treated cases. Two cases of severe PVS subsequently developed PV thrombosis. Intervention by balloon dilation and/or stenting was performed successfully in this PVS case. CONCLUSION: DUS is the most convenient and efficient imaging modality to detect and follow postoperative PVS in ALDLT. The Doppler criteria of SR and VR are both sensitive but less specific. Cases of AS<5 mm require interventional management for good long-term graft survival.