Utilization of older deceased donors for pediatric liver transplant may negatively impact long-term survival

BACKGROUND

Multiple adult studies have investigated the role of older donors (ODs) in expanding the donor pool. However, the impact of donor age on pediatric liver transplantation (LT) has not been fully elucidated.

METHODS

UNOS database was used to identify pediatric (≤18 years) LTs performed in the United States during 2002-22. Donors ≥40 years at donation were classified as older donors (ODs). Propensity analysis was performed with 1:1 matching for potentially confounding variables.

RESULTS

A total of 10,024 pediatric liver transplantation (PLT) patients met inclusion criteria; 669 received liver grafts from ODs. Candidates receiving OD liver grafts were more likely to be transplanted for acute liver failure, have higher Model End-Stage Liver Disease/Pediatric End-Stage Liver Disease (MELD/PELD) scores at LT, listed as Status 1/1A at LT, and be in the intensive care unit (ICU) at time of LT (all p < 0.001). Kaplan-Meier (KM) analyses showed that recipients of OD grafts had worse patient and graft survival (p < 0.001) compared to recipients of younger donor (YD) grafts. KM analyses performed on candidates matched for acuity at LT revealed inferior patient and graft survival in recipients of deceased donor grafts (p < 0.001), but not living donor grafts (p > 0.1) from ODs. Cox regression analysis demonstrated that living donor LT, diagnosis of biliary atresia and first liver transplant were favorable predictors of recipient outcomes, whereas ICU stay before LT and transplantation during 2002-12 were unfavorable.

CONCLUSION

Livers from ODs were used for candidates with higher acuity. Pediatric recipients of livers from ODs had worse outcome compared to YDs; however, living donor LT from ODs had the least negative impact on recipient outcomes.

The impact of a dedicated operating room team on robotic transplant program growth and fellowship training

INTRODUCTION

Despite considerable interest in robotic surgery, successful incorporation of robotics into transplant programs has been challenging. Lack of a dedicated OR team with expertise in both robotics and transplant is felt to be a major barrier. This paper assesses the impact of a dedicated robotic transplant team (DART) on program growth and fellowship training at one of the largest robotic transplant programs in North America.

METHODS

This is a single center, retrospective review of all robotic operations performed on the transplant surgery service from October 2017 to October 2022. DART was incorporated in February 2020 and included transplant first assists (RFAs), scrub technologists and circulating nurses who received robotic training. Robotic experience before and after DART was compared to assess its impact on program growth and training.

RESULTS

Four hundred and two robotic cases were performed by five transplant surgeons: 63 pre-DART and 339 post-DART. 40% of cases were transplant-related and 59.5%, HPB. There was a significant increase in case volume (2.5-10.6 cases/month, p < .0001) and complexity (36.5% vs. 70.3% high complexity cases, p < .0001) post-DART. RFA case coverage increased from 17% to 95%, and participation of transplant fellows as primary surgeons increased from 17% to 95% post-DART period (both p < .05). Conversion rates (9.5% vs. 4.1%) and room turn-around-times (TAT) (58.4 vs. 40.3 min) were lower post-DART (p < .05). There were no emergent conversions, conversions in transplant patients, or robot-related complications in either group.

CONCLUSION

OR teams with expertise in robotics and transplant surgery can accelerate growth of robotic transplant programs while maintaining patient safety.

Global liver transplantation: emerging trends and ethical challenges

PURPOSE

Liver transplant (LT) is the only definitive treatment for end-stage liver disease (ESLD). This review aims to explore current global LT practices, with an emphasis on challenges and disparities that limit access to LT in different regions of the world.

METHODS

A detailed analysis was performed of present-day liver transplant practices throughout the world, including the etiology of liver disease, patient access to transplantation, surgical costs, and ongoing ethical concerns.

RESULTS

Annually, only 10% of the patients needing a liver transplant receive an organ. Currently, the USA performs the highest volume of liver transplants worldwide, followed by China and Brazil. In both North America and Europe, nonalcoholic fatty liver disease is becoming the most common indication for LT, compared to hepatitis B and C in most Asian, South American, and African countries. While deceased donor liver transplant remains the most performed type of LT, living donor liver transplant is becoming increasingly popular in some parts of the world where it is often the only option due to a lack of well-developed infrastructure for deceased organ donation. Ethical concerns in liver transplantation fundamentally revolve around the definition of a deceased donor and the exploitation of living donor liver donation systems.

CONCLUSION

Globally, liver transplant practices and outcomes are varied, with differences driven by healthcare policies, inequities in healthcare access, and ethical concerns.

Robotic donor nephrectomy: optimizing outcomes beyond the limitations of laparoscopy

BACKGROUND

Robotic donor nephrectomy (RDN) has emerged as a safe alternate to laparoscopic donor nephrectomy (LDN), offering improved visualization, instrument dexterity and ergonomics. There is still concern about how to safely transition from LDN to RDN.

METHODS

We performed a retrospective review of 150 consecutive living donor operations (75 LDN and 75 RDN) at our center, comparing the first 75 RDN's with the last 75 LDN's performed prior to the initiation of the robotic transplant program. Operative times and complications were used as surrogates of efficiency and safety, respectively, to estimate the learning curve with RDN.

RESULTS

RDN was associated with a longer total operative time (RDN 182 vs LDN 144 min; P < 0.0001) but a significantly shorter post-operative length of stay (RDN 1.8 vs LDN 2.1 days; P = 0.0213). Donor complications and recipient outcomes were the same between both groups. Learning curve of RDN was estimated to be about 30 cases.

CONCLUSIONS

RDN is a safe alternate to LDN with acceptable donor morbidity and no negative impact on recipient outcomes even during the early part of the RDN learning curve. Surgeon preferences for the robotic approach compared to traditional laparoscopy will require further scrutiny to improve ergonomics and operative efficiency.

Liver Transplantation After Hepatic Artery Infusion Pump Therapy: Single-Center Experience and Technical Considerations

BACKGROUND

Hepatic artery infusion pump (HAIP) therapy has become increasingly commonplace in the treatment of intrahepatic tumors. When combined with standard chemotherapy, HAIP therapy demonstrates a higher response rate than chemotherapy alone. Biliary sclerosis is observed in up to 22 % of patients, for whom no treatment has been standardized. This report describes orthotopic liver transplantation (OLT) both as a treatment for HAIP-induced cholangiopathy and as a possible definitive oncologic treatment after HAIP-bridging therapy.

METHODS

A retrospective study reviewed patients who had undergone HAIP placement followed by OLT at the authors' institution. Patient demographics, neoadjuvant treatment, and postoperative outcomes were reviewed.

RESULTS

Seven OLTs were performed for patients with prior HAIP placement. The majority were women (n = 6), and the median age was 61 years (range, 44.5-65.5 years). Transplantation was performed for five patients due to biliary complications secondary to HAIP and two patients because of residual tumor after HAIP therapy. All the OLTs had difficult dissections due to adhesions. Because of HAIP-induced damage, atypical arterial anastomoses were required in six patients (2 patients used a recipient common hepatic artery below the gastroduodenal artery takeoff; 2 patients used recipient splenic arterial inflow; 1 patient used the junction of the celiac and splenic arteries; and 1 patient used the celiac cuff). The one patient with standard arterial reconstruction experienced an arterial thrombosis. The graft was salvaged with thrombolysis. Biliary reconstruction was duct-to-duct in five cases and Roux-en-Y in two cases.

CONCLUSIONS

The OLT procedure is a feasible treatment option for end-stage liver disease after HAIP therapy. Technical considerations include a more challenging dissection and an atypical arterial anastomosis.

Circadian regulation of dentate gyrus excitability mediated by G-protein signaling

The central circadian regulator within the suprachiasmatic nucleus transmits time of day information by a diurnal spiking rhythm driven by molecular clock genes controlling membrane excitability. Most brain regions, including the hippocampus, harbor similar intrinsic circadian transcriptional machinery, but whether these molecular programs generate oscillations of membrane properties is unclear. Here, we show that intrinsic excitability of mouse dentate granule neurons exhibits a 24-h oscillation that controls spiking probability. Diurnal changes in excitability are mediated by antiphase G-protein regulation of potassium and sodium currents that reduce excitability during the Light phase. Disruption of the circadian transcriptional machinery by conditional deletion of Bmal1 enhances excitability selectively during the Light phase by removing G-protein regulation. These results reveal that circadian transcriptional machinery regulates intrinsic excitability by coordinated regulation of ion channels by G-protein signaling, highlighting a potential novel mechanism of cell-autonomous oscillations.

Randomized controlled trial comparing the McGrath videolaryngoscope with the C-MAC videolaryngoscope in intubating adult patients with potential difficult airways

BACKGROUND

Difficult and failed intubations, although rarely encountered, are major causes of morbidity and mortality in the current anaesthetic practice. To reduce the incidence of difficult and failed intubations, several devices including the recently developed videolaryngoscopes are available. This randomized controlled study aims to compare the use of the McGrath videolaryngoscope with the C-MAC videolaryngoscope in adult patients with potential difficult airways.

METHODS

A total of 130 patients with the Mallampati grade of ≥3, requiring orotracheal intubation, were randomized to either having intubation with the McGrath videolaryngoscope or the C-MAC videolaryngoscope. The primary outcome was time to intubation. The laryngoscopic view, the number of intubation attempts, the proportion of intubation success, the ease of intubation, the haemodynamic responses to intubation, and the incidence of any complications were also recorded.

RESULTS

Time to successful intubation with the C-MAC videolaryngoscope was shorter when compared with the McGrath videolaryngoscope {50 s [inter-quartile range (IQR) 38-70] vs 67 s (IQR 49-108), P<0.001}, despite the McGrath videolaryngoscope providing significantly more grade 1 laryngoscopic views. The C-MAC videolaryngoscope also resulted in significantly fewer intubation attempts and greater ease of intubation when compared with the McGrath videolaryngoscope. There were no statistically significant differences in the proportion of intubation success, the number of complications, and the changes in haemodynamic responses between the two videolaryngoscopes.

CONCLUSIONS

The C-MAC videolaryngoscope allowed a quicker intubation time, fewer intubation attempts, and greater ease of intubation compared with the McGrath videolaryngoscope when used in patients with the Mallampati grade of ≥3.

Dose-associated changes in safety and efficacy parameters observed in a 24-week maintenance trial of olanzapine long-acting injection in patients with schizophrenia

BACKGROUND

In a recently published 24-week maintenance study of olanzapine long-acting injection (LAI) in schizophrenia (Kane et al., 2010), apparent dose-associated changes were noted in both efficacy and safety parameters. To help clinicians balance safety and efficacy when choosing a dose of olanzapine LAI, we further studied these changes.

METHODS

Outpatients with schizophrenia who had maintained stability on open-label oral olanzapine for 4 to 8 weeks were randomly assigned to "low" (150 mg/2 weeks; N = 140), "medium" (405 mg/4 weeks; N = 318), or "high" (300 mg/2 weeks; N = 141) dosages of olanzapine LAI for 24 weeks. Potential relationships between dose and several safety or efficacy measures were examined via regression analysis, the Jonckheere-Terpstra test (continuous data), or the Cochran-Armitage test (categorical data).

RESULTS

Safety parameters statistically significantly related to dose were mean weight change (low: +0.67 [SD = 4.38], medium: +0.89 [SD = 3.87], high: +1.70 [SD = 4.14] kg, p = .024; effect size [ES] = 0.264 high vs. low dose), mean change in prolactin (low: -5.61 [SD = 12.49], medium: -2.76 [SD = 19.02]), high: +3.58 [SD = 33.78] μg/L, p = .001; ES = 0.410 high vs. low dose), fasting triglycerides change from normal at baseline to high (low: 3.2%, medium: 6.0%, high: 18.9%, p = .001; NNT = 7 high vs. low dose) and fasting high-density lipoprotein cholesterol change from normal at baseline to low (low: 13.8%, medium: 19.6%, high: 30.7%, p = .019; NNT = 6 high vs. low dose). Efficacy measures significantly related to dose included Positive and Negative Syndrome Scale total score mean change (low: +2.66 [SD = 14.95], medium: -0.09 [SD = 13.47], high: -2.19 [SD = 13.11], p <.01; ES = 0.356 high vs. low dose), relapse rate (low: 16%, medium: 10%, high: 5%, p = .003; NNT = 9 high vs. low dose), all-cause discontinuation rate (low: 36%, medium: 30%, high: 24%, p = .037; NNT = 9 high vs. low dose), and rate of discontinuation due to efficacy-related reasons (low: 20%, medium: 14%, high: 6%, p <.001). Time to all-cause discontinuation (p = .035) and time to relapse (p = .005) were also significantly related to dose.

CONCLUSIONS

Analyses of several safety and efficacy parameters revealed significant associations with dose of olanzapine LAI, with the highest dose generally showing greater efficacy as well as greater adverse changes in metabolic safety measures. When considering olanzapine LAI, as with all antipsychotics, it is important to carefully consider the potential benefits and risks for an individual patient.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00088491.

Regulation of pentraxin-3 by antioxidants

BACKGROUND

Pentraxin-3 (PTX3) may be a useful biomarker in sepsis, but its regulatory mechanisms are still unclear. Oxidative stress is well defined in patients with sepsis and has a role in regulation of inflammatory pathways which may include PTX3. We undertook an in vitro study of the effect of antioxidants on regulation of PTX3 in endothelial cells combined with a prospective observational pilot study of PTX3 in relation to markers of antioxidant capacity and oxidative stress in patients with sepsis.

METHODS

Human endothelial cells were cultured with lipopolysaccharide 2 microg ml(-1), peptidoglycan G 20 microg ml(-1), tumour necrosis factor (TNF) alpha 10 ng ml(-1), interleukin-1 (IL-1) beta 20 ng ml(-1), or killed Candida albicans yeast cells plus either N-acetylcysteine (NAC) 25 mM, trolox 100 mM, or idebenone 1 microM. Plasma samples were obtained from 15 patients with sepsis and 11 healthy volunteers.

RESULTS

PTX3 levels in plasma were higher in patients with sepsis than in healthy people [26 (1-202) ng ml(-1) compared with 6 (1-12) ng ml(-1), P=0.01]. Antioxidant capacity was lower in patients with sepsis than healthy controls [0.99 (0.1-1.7) mM compared with 2.2 (1.3-3.3) mM, P=0.01]. In patients with sepsis, lipid hydroperoxide levels were 3.32 (0.3-10.6) nM and undetectable in controls. We found no relationship between PTX3 and antioxidant capacity or lipid hydroperoxides. Cell expression of PTX3 increased with all inflammatory stimulants but was highest in cells treated with TNFalpha plus IL-1beta. PTX3 concentrations were lower in cells co-treated with antioxidants (all P<0.05), associated with lower nuclear factor kappaB expression for NAC and trolox (P<0.05).

CONCLUSIONS

PTX3 expression is down-regulated in vitro by antioxidants. Plasma levels of PTX3 are elevated in sepsis but seem to be unrelated to markers of oxidant stress or antioxidant capacity.

Dose response and atypical antipsychotics in schizophrenia

Based on information from clinical trials, both the efficacy and adverse effects of conventional antipsychotics in the treatment of schizophrenia are dose related. The overlapping nature of these dose-response profiles limits the use of these agents. Atypical antipsychotics provide greater relief across the comorbid symptom domains of schizophrenia, but dose-response studies and clinical experience have revealed that some of these drugs also have dose limitations. This article reviews the dose-response relationships of the atypical antipsychotics as presented predominantly in pivotal, randomised studies (double-blind and otherwise). Limited data indicate that clozapine shows dose-related efficacy up to 600 mg/day in patients with treatment-resistant schizophrenia. However, higher dosages of clozapine may be associated with the risk of seizures. Risperidone demonstrates dose-related adverse events that compromise efficacy. The dose-response relationships for ziprasidone, quetiapine and aripiprazole are less well established. The efficacy of olanzapine appears to be dose related within the recommended dosage range of 10-20 mg/day, but clinical trials that have explored higher dosages suggest improved efficacy. Furthermore, the higher doses are not associated with a significantly increased incidence of adverse events. Further studies are clearly needed to fully characterise the dose-response relationships of atypical antipsychotics.

Effectiveness of rapid initial dose escalation of up to forty milligrams per day of oral olanzapine in acute agitation

BACKGROUND

Patients experiencing an acute decompensation of schizophrenia or bipolar disorder often present in an agitated state. Agitation presents a barrier to therapy, interrupting the typical physician-patient alliance and creating a disruptive, even hazardous, environment. Rapid assessment and effective treatment are necessary to manage agitation and, potentially, to shorten the time to recovery.

METHODS

One hundred forty-eight acutely agitated patients received either: rapid initial dose escalation (RIDE) in which up to 40 mg of oral olanzapine was allowed on days 1 and 2, up to 30 mg on days 3 and 4, and 5 to 20 mg thereafter; or usual clinical practice (UCP) in which patients received 10 mg/d olanzapine plus up to 4 mg lorazepam on days 1 and 2, up to 2 mg on days 3 and 4, and olanzapine 5 to 20 mg/d thereafter. The Positive and Negative Syndrome Scale-Excited Component (PANSS-EC: poor impulse control, tension, hostility, uncooperativeness, and excitement) measured at 24 hours was the primary measure. Secondary assessments of agitation and safety were also performed.

RESULTS

Agitation improved significantly from baseline for both treatment groups; however, improvement with the RIDE strategy was superior to UCP. The RIDE group improvement was superior on the primary efficacy measure (PANSS-Excited) at 24 hours; it was superior on all agitation measures at the end of double-blind treatment. Both treatments were well tolerated, with no clinically significant differences in safety measures. Treatment was not limited by oversedation and attention improved from baseline in both groups.

CONCLUSIONS

This study demonstrates the value of olanzapine in the treatment of acutely agitated patients. A new approach to olanzapine dosing that expands the initial dose range up to 40 mg/d may offer superior efficacy in rapidly and effectively controlling the symptoms of agitation.

Olanzapine orally disintegrating tablets in the treatment of acutely ill non-compliant patients with schizophrenia

The objective of this study was to determine if the orally disintegrating tablet formulation of olanzapine, Zyprexa Zydis, would facilitate antipsychotic medication compliance in acutely ill, non-compliant patients. Eighty-five acutely ill patients with schizophrenia or schizoaffective disorder who met medication non-compliance criteria received open-label olanzapine orally disintegrating tablets (1020 mgd) for up to 6 wk. Improvement in medication compliance was assessed using various rating scales to measure changes in psychopathology, medication-taking and compliance attitudes, and nursing care burden. Safety variables were also measured. Significant improvement from baseline was demonstrated in the Positive and Negative Syndrome Scale total score at Week 1 and subsequently (p0.001). Significant improvement from baseline was also seen in various scales measuring medication compliance, attitude, and nursing care burden (p0.05). Olanzapine orally disintegrating tablets were well-tolerated. Olanzapine orally disintegrating tablets may benefit acutely ill, non-compliant schizophrenic patients by facilitating acceptance of active antipsychotic drug therapy.

Funneling to the stitch: an informative ultrasonographic finding after cervical cerclage

OBJECTIVE

The purpose of this study was to evaluate the utility of ultrasound surveillance after cerclage placement and to propose a rationale for cervical sonography in this setting.

SUBJECTS AND METHODS

This was a retrospective analysis of 53 women undergoing cervical cerclage by a maternal-fetal medicine specialist, regardless of indication, and delivering between January 1999 and April 2001. Transvaginal ultrasonographic assessment of cervical length and the degree of cervical funneling after cerclage were compared to preoperative values and to outcomes including gestational age at delivery. Funneling to the cerclage was defined as membranes prolapsing down the endocervical canal until they reached the plane of the cerclage.

RESULTS

Cervical cerclage resulted in a significant increase in cervical length from 2.1 +/- 1.2 cm to 2.9 +/- 0.8 cm after the procedure, P < 0.001; however, this measure was not correlated with gestational age at delivery. Funneling to the level of the cerclage was associated with an earlier gestational age at delivery 31.3 +/- 5.6 weeks vs. 36.8 +/- 2.8 weeks for those cases without this finding, P < 0.001. A statistically significant association between funneling to the cerclage and preterm delivery was identified irrespective of the indication (prophylactic or emergency) for the procedure. When descent of the membranes to the level of the cerclage was noted, it occurred by 28 weeks' gestation in all patients studied. The incidence of premature rupture of the membranes was also significantly greater postcerclage in women with descent of the membranes to the cerclage (52%) compared to those without this finding (9%) P= 0.002.

CONCLUSIONS

Funneling to the cerclage is significantly associated with earlier preterm delivery in patients who have undergone cervical cerclage. Serial sonography up to 28 weeks' gestation is useful in identifying patients at higher risk for premature rupture of the membranes and preterm delivery.

Identification of the Xenopus laevis cDNA for EXT1: a phylogenetic perspective

The EXT family of genes is involved in the developmentally important biosynthesis of heparan sulfate molecules. Members of the EXT family have a demonstrated role in gastrulation, wing formation in flies, and proper bone development in vertebrates. EXT family members have been isolated from several phylogenetically diverse species. We report here, the isolation of the first Xenopus laevis EXT1 family member and discuss the evolutionary origins of this gene family.

Effective resolution with olanzapine of acute presentation of behavioral agitation and positive psychotic symptoms in schizophrenia

Behavioral agitation and prominent positive psychotic symptoms often characterize the acute presentation of schizophrenia. The clinical treatment goal is a rapid control of these symptoms. The relative efficacy of olanzapine, a novel antipsychotic drug, was compared with that of the conventional antipsychotic drug haloperidol. A post hoc analysis conducted on a large multicenter, double-blind, 6-week study of acute-phase patients with DSM-III-R schizophrenia or schizophreniform or schizoaffective disorders treated with olanzapine (5-20 mg/day) or haloperidol (5-20 mg/day) assessed the treatment effects on agitation (Brief Psychiatric Rating Scale [BPRS] agitation score) and positive symptoms (BPRS positive symptom score). Overall, olanzapine-treated patients experienced significantly greater improvement in behavioral agitation than did haloperidol-treated patients (last observation carried forward [LOCF]; p < .0002). Both groups showed similar reductions in agitation scores during the first 3 weeks of therapy; olanzapine was associated with significantly greater improvements at weeks 4, 5, and 6 (observed cases [OC]). Similarly, patients with predominantly positive psychotic symptoms experienced significantly greater improvement in BPRS positive symptom scores with olanzapine compared with haloperidol (LOCF; p = .013). In olanzapine-treated patients, improvement in BPRS agitation and positive symptom scores was significantly greater at weeks 4, 5, and 6 (agitation scores, p < or = .01; positive symptom scores, p < .05) (OC). These data suggest that olanzapine may be considered a first-line treatment for the patient in an acute episode of schizophrenia.

Efficacy of transdermal nicotine in reducing post-cessation weight gain in a Hispanic sample

This study examined nicotine replacement effects and pre-quit smoking characteristics with respect to post-cessation weight gain in a primarily Mexican-American sample of Hispanic smokers. Hispanic smokers (108) were randomly assigned to receive either nicotine transdermal patch or placebo patch for 10 weeks, during which time smoking status and weight change were measured. The overall weight gain experienced by the successful quitters was greater than that experienced by non-quitters. Differences between quitters and non-quitters were significant for both females (2.0 vs. 0.86 kg; p < 0.05) and for males (2.3 vs. 1.2 kg; p < 0.05) at 6 weeks post-randomization. At the end of the 10-week treatment, only the females showed a significant difference in weight gain between the quitters and non-quitters (2.8 vs. 1.1; p < 0.01). Results of the random effects regression models for quitters indicated that the active group gained weight at a significantly lower rate than the placebo group (p = 0.047) for females, but not for males (p = 0.87). Years of smoking (p = 0.001) but not baseline cigarettes (p = 0.13) were significant predictors of weight for females, but not for males (p = 0.24 and 0.72, respectively). The use of nicotine patch treatment for smoking cessation effectively attenuated weight gain for successful female quitters compared with placebo-treated quitters. Identification of pre-quit smoking characteristics may prove useful in predicting who is most likely to gain weight when quitting smoking.

Discriminability measures for predicting readability of text on textured backgrounds

Several discriminability measures were examined for their ability to predict reading search times for three levels of text contrast and a range of backgrounds (plain, a periodic texture, and four spatial-frequency-filtered textures created from the periodic texture). Search times indicate that these background variations only affect readability when the text contrast is low, and that spatial frequency content of the background affects readability. These results were not well predicted by the single variables of text contrast (Spearman rank correlation = -0.64) and background RMS contrast (0.08), but a global masking index and a spatial-frequency-selective masking index led to better predictions (-0.84 and -0.81, respectively).

Half value layer measurements to facilitate patient dose assessment for newer CT scanners using published normalized dose data

The National Radiological Protection Board (NRPB) method of calculating patient doses from CT can be applied to scanners not represented in normalized dose data sets, published in NRPB Report R250, if an appropriate existing data set is selected. A method of matching scanner models to data sets is currently being developed in a national scanner survey, organized by the Department of Health ImPACT CT evaluation group. This paper demonstrates the use of an alternative method of data set selection to that employed in the national study, by application to the Picker PQCT and Siemens +4 scanners. Half value layers (HVLs) evaluated at the isocentre and at intervals within the fan angle of the X-ray beam of either the Picker PQCT or Siemens +4 were compared with HVLs for three scanner models represented in the NRPB data sets. A good match indicates the suitability of a normalized dose data set, since data sets are dependent on the quality of the X-ray beam incident on a patient. The results demonstrate that Picker 1200SX data sets could be used with the Picker PQCT scanner. The most likely match for the Siemens +4, from the limited number of scanners investigated, was identified as being the Philips Tomoscan LX.

Reduced expression of pax-3 is associated with overexpression of cdc46 in the mouse embryo

CDC46/MCM5 encodes a protein that is highly conserved among yeast, plants, and animals. It is found in a complex which exhibits DNA replication licensing activity, which is proposed to regulate the synthesis of DNA once and only once per cell cycle. In yeast, loss of function mutations of CDC46/MCM5 decrease DNA synthesis. Very little is known about the regulation of CDC46/MCM5 in any species. We report here that, in the mouse embryo, expression of cdc46 is increased in unfused portions of the neural tube when the gene encoding the transcription factor, Pax-3, is either nonfunctional or underexpressed. These results were observed both in embryos of diabetic mice, which we have previously shown express significantly reduced levels of Pax-3 mRNA, and in Splotch embryos, which carry loss of function Pax-3 alleles. This indicates that expression of cdc46 is negatively regulated as part of a Pax-3-dependent pathway. Since cdc46 appears to regulate DNA synthesis and cell cycle progression, it is possible that its overexpression is involved in defective embryonic development that is associated with loss of Pax-3 function.

Effects of nicotine dose and administration method on withdrawal symptoms and side effects during short-term smoking abstinence

The effects of using several nicotine replacement treatments on self-reported withdrawal symptoms and side effects during 2-day periods of smoking cessation, with 5 days of ad lib smoking between cessation days, were evaluated. Participants (N = 18) experienced the following conditions: nicotine gum, 24-hr patch, 16-hr patch, 24-hr patch plus gum, double 24-hr patch, and no nicotine replacement. The present study found morning urge to smoke was greater during the 16-hr than during the 24-hr patch condition. Double-patch use resulted in significantly greater insomnia than the smoking baseline and 16-hr patch conditions. The no medication and gum alone conditions resulted in similar withdrawal symptoms, and both tended to result in greater reported withdrawal symptoms than the smoking baseline condition. There were no significant withdrawal symptom differences between the 24-hr, patch-gum, and double-patch conditions. The 24-hr and double-patch conditions were preferred by two thirds of the participants (6 each).

Generalized use of over-the-counter analgesics: relationship to premenstrual symptoms

This study tested the hypothesis that use of nonprescription analgesics among women scoring high on premenstrual distress may generalize to time periods beyond the premenstrual phase. Fifty three female undergraduates completed Form C of the Moos Menstrual Distress Questionnaire and described their typical use of analgesics during the "average week." Results showed that symptoms of premenstrual distress were significantly related to both the frequency of analgesic use and the quantity consumed per occasion. These findings support the generalization hypothesis proposed by Blechman and her colleagues.

Normal ageing in adults with Down's syndrome: a longitudinal study

The ubiquitous presence of the neuropathology of Alzheimer disease (AD) in individuals with Down's syndrome (DS) over 40 years of age suggests that this group of people will exhibit a high prevalence of dementia of the Alzheimer type (DAT) as they age. The present study indicates that there is a clear discrepancy between the presumed presence of AD neuropathology and the clinical expression of DAT among older people with DS. In the first 6 years of a longitudinal study, the present authors compared 91 adults (31-63 years of age) with DS and mild or moderate mental retardation to 64 adults (31-76 years of age) with other forms of mental retardation (MR) on yearly measures of mental status, short- and long-term memory, speeded psychomotor function, and visuospatial organization. The results indicated that, over repeated testing on the verbal long-term memory test, younger participants with DS showed small increases in their scores, while older participants with DS showed very slight decreases. Overall performance scores on this test and a speeded psychomotor task were poorer for both diagnostic groups in individuals aged 50 years and older. The magnitude and type of these selective changes in performance were consistent with performance profiles observed in older healthy adults without mental retardation on tests measuring similar cognitive functions. Only four out of the 91 people with DS in the present sample showed changes in functioning that have led to a diagnosis of possible DAT, and in these individuals, alternative causes of performance declines were concurrently present (e.g. thyroid dysfunction). These findings indicate that some age-associated changes in functioning are related to "normal' but probably precocious ageing among adults with DS. Furthermore, these findings suggest that adults with DS and mild or moderate mental retardation may be at lower risk for dementia during their fourth and fifth decades of life than previous studies have suggested.

Ultrasound quantitation of respiratory organ motion in the upper abdomen

Organ motion can cause artefacts in abdominal imaging particularly with magnetic resonance imaging (MRI), and may often limit the diagnostic quality of an image. If spatial resolution and image quality are to improve in MRI and other imaging techniques, a more detailed understanding of organ motion is required. Despite the importance of organ motion little quantitative information is available to date. This study was the continuation of work instigated to investigate and quantify respiratory movements of upper abdominal organs for a group of healthy volunteers in order to provide the design criteria for a motion test object for use in MRI. A previous phase of the project allowed construction of a test object but refinements were needed to represent respiratory motion more closely as a consequence of the data presented in this paper. Improvements in the scanning technique and the recording procedure have revealed that, contrary to our initial findings, motion of the diaphragm and liver is predominantly in the superior-inferior (SI) direction with an average displacement (+/- SD) (quiet respiration) of 12 +/- 7 mm (range 7-28 mm) and 10 +/- 8 mm (range 5-17 mm), respectively. For some volunteers, motion of the kidneys can be complex, especially during deep inspiration. New data have been provided by this phase of the motion study on the displacement, velocity and acceleration of abdominal organs as a function of time. These data show that MRI motion artefact reduction techniques which assume that either organ displacement, velocity or acceleration are constant are only applicable during certain phases of the respiratory cycle.

Effect of addition of exercise to chest physiotherapy on sputum expectoration and lung function in adults with cystic fibrosis

Promotion of sputum expectoration by chest physiotherapy is an essential part of cystic fibrosis management. The role of exercise in improving sputum expectoration and lung function in these patients is more contentious. We therefore investigated the effect of adding an exercise programme to conventional chest physiotherapy in eight adult subjects (four male) with cystic fibrosis. Subjects were treated on two non-consecutive days of the second week of a course of in-patient antibiotic therapy in a cross-over fashion. On the exercise and physiotherapy day, subjects exercised 60 min before physiotherapy. On the physiotherapy alone day, subjects rested for 60 min instead of exercising. Physiotherapy was administered on both study days (postural drainage, percussion, deep breathing, vibrations, forced expiratory technique and coughing). Lung function tests were performed at baseline, after exercise or rest and again immediately and 30 min after physiotherapy. Sputum weights were measured in the 60 min of exercise or rest (period A) and for the 60 min physiotherapy period and 30 min after physiotherapy (period B). Mean total sputum expectoration (period A and B) was 14 g on physiotherapy alone and 21.5 g (4.8) on exercise and physiotherapy (mean difference 7.5 g, 95% CI 1.4-13.6 g, P = 0.02). Mean sputum weights during period A (i.e. rest vs. exercise) on physiotherapy alone and exercise and physiotherapy were 2.6 and 7 g respectively (mean difference 4.4 g, 95% CI-0.07-8.8 g, P = 0.053).(ABSTRACT TRUNCATED AT 250 WORDS)

Deoxyribonucleic acid (DNA) analysis by restriction fragment length polymorphisms of blood and other body fluid stains subjected to contamination and environmental insults

Deoxyribonucleic acid (DNA) restriction fragment length polymorphism (RFLP) profile results were obtained from bloodstains and other body fluid stains subjected to mixture with other body fluids, environmental insults (sunlight and temperature), different substrates (cotton, nylon, blue denim, glass, aluminum, and wood), and contaminants (gasoline, bleach, sodium hydroxide, soil, motor oil, detergent, phosphate salt, glacial acetic acid, and microorganisms). Of the samples that produced profile results, all had profiles that were consistent with those of untreated control samples.

A profile of cognitive deficit in females from fragile X families

Fragile X, a recently discovered X-linked syndrome, is usually associated with mental retardation in affected males. Less consistent findings have been described for females. neuropsychological evaluation of seven nonretarded females from fragile X families suggested a characteristic profile: on Wechsler IQ tests, a positive Verbal-Performance score difference and lower subtest scaled scores on Arithmetic, Digit Span, Block Design, and Object Assembly; on the Wide Range Achievement Test, a lower score on Arithmetic than on Reading or Spelling; and on the Benton Visual Retention Test, defective recall. These results suggest the existence of X-linked learning disability in females.

Fragile X syndrome: associated neurological abnormalities and developmental disabilities

The fragile X syndrome is a frequent cause of developmental disabilities. It is associated primarily with nonprogressive X-linked mental retardation. The neurodevelopmental abnormalities of 25 males and 3 females are described. Mental retardation was mild in 4, moderate in 11, severe in 6, and profound in 2 patients, while 4 patients had only learning disabilities. The presence or absence of a developmental disability could not be determined in the youngest (8 months). Seven patients had had infantile autism and 7 had epilepsy. Generally no major focal neurological abnormalities were observed but most of the patients exhibited minor signs. The severity of developmental disabilities in our patients varied between and within families and between genders. All adult males had macroorchidism. Unusual facial features were present in 13 males but none were seen in the females. Familial occurrences were found in 18 cases (64%); 10 cases (36%) were sporadic. Overall, males were more severely affected than females. Diagnostic tests including computed tomographic scans, electroencephalograms, and evoked potentials did not disclose any specific abnormalities.

Folic acid therapy in the fragile X syndrome

Two brothers with fra(X) positive X-linked mental retardation (XLMR) were treated with folic acid. Initially a double blind cross-over design was employed followed by a long-term high dose trial. A decrease in the frequency of fra(X) positive cells was observed when low folic acid culture medium was used but not when an FUdR induction system was employed. Selected behavioral characteristics improved in both while receiving folic acid. Decreased hyperactivity, greater attention span, increased motor coordination, increased quantity and quality of speech were noted. Improvement in Leiter mental age and regression after cessation of treatment was seen in one subject but not in the other. Further controlled trials with larger numbers of subjects using high doses of folic acid over longer periods of time are needed to assess the possible benefits of this experimental form of treatment.

Use of CT to reduce understaging in prostatic cancer: comparison with conventional staging techniques

Thirty prostatic cancer patients were evaluated for staging purposes with both CT (18-sec scan speed) and certain commonly used "conventional" diagnostic tests, namely: radionuclide bone scan with correlative plain films, the prostatic fraction of the serum acid phosphatase, excretory urogram, and chest radiograph. All patients included in the study had histopathologic proof of diagnosis. CT correctly identified extracapsular prostatic cancer spread locally or in pelvic lymph nodes in 14% of patients with completely negative conventional studies. Sensitivity of extracapsular tumor spread detection increased from 41% to 59% by adding CT to the conventional studies. CT confirmed the presence of tumor spread and localized it in 43% of patients with positive conventional studies. Conventional studies were positive when tumor spread was present in 32% of patients with negative CT. CT reduces understaging when conventional tests are negative, localizes and confirms tumor spread when conventional tests are positive, but cannot demonstrate tumor spread in some patients whose conventional tests are positive and who are subsequently shown to have tumor spread histopathologically.

WAIS subtest score characteristics of institutionalized mentally retarded samples

Scaled scores on WAIS subtests were compared among five samples of institutionalized mentally retarded (aged 16 to 71 yr.) from the East Coast (N = 509), West Coast (N = 436), and three from the Midwest (Ns = 113, 51, and 111). Four of the five samples showed high correlations between the mean profiles suggesting that the performance of the mentally retarded is reliable across geographical locations. Reasons for the discrepancies between these four samples and the fifth sample are discussed.

Visual perseveration in normal and mentally retarded children

Visual perseveration was investigated within mentally retarded and second, fifth, and eighth grade normal children (Ns = 12 each group). Subjects matched an auditorially presented click to the onset and offset of visually presented stimuli. Time differences between visual stimulus offset and the point at which subjects reported simultaneity of the click and visual stimulus offset was assumed to reflect visual perseveration. Results showed: (a) no differences between the normal children as a function of age; (b) no difference between groups for stimuli of 100 msec. or longer duration; and (c) retarded subjects judged stimuli of 20 and 50 msec. to be of shorter duration than did normal subjects. This highly specific distinction between retarded and normal subjects suggests a difference in an early stage of perceptual processing.

Idiot savants: rate of incidence

Based on the replies to a survey of 300 public residential facilities for the mentally retarded, an incidence rate for idiot savants was established. This rate of .06% is based on the reporting of 54 idiot savants within a population of 90,000 residents. Several reasons for caution in the acceptance of this incidence rate are discussed.

Bisecting the Ponzo illusion

A modification of the Ponzo illusion, in which the judged lines are centered in different sized obliques, was presented to matched normal and mentally retarded males (ns = 8) under conditions of equal and unequal retinal sizes. Magnitude of illusion was affected by IQ (WISC) and by physical proximity rather than retinal contour. The results seem to imply a central rather than peripheral explanation for the illusion.

An investigation of calendar calculating by an idiot savant

Three mechanisms (eidetic imagery, high-speed calculation, and substitute compensation for normal learning) were investigated and rejected as possible explanations for the calendar-calculating ability of a particular idiot savant. Reaction times for calendar calculations indicated that he used neither an idiosyncratic nor a calendar-based system. Rote memory and a special ability to concentrate for extended periods of time were postulated to explain this individual's performance.

Examination of Pressey's assimilation theory of the Poggendorff illusion

Predictions based on Pressey's assimilation theory of the Poggendorff illusion were tested on a new form of the illusion. The results indicated that modifications of the assimilation theory were necessary and a proposed modification was discussed.

Mongolian Idiocy in Japanese: Report of Two Cases

Images