Increasing cognitive load attenuates the moderating effect of attentional inhibition on the relationship between posttraumatic stress symptoms and threat-related attention bias variability

Theory and empirical evidence suggest that those with higher posttraumatic stress (PTS) symptoms and better attentional control (i.e., the strategic control of higher-order executive attention in regulating bottom-up, stimulus driven responses to prepotent stimuli; Sarapas et al., 2017) can use that ability to disengage and shift attention away from threat stimuli and reduce threat-related attentional dysregulation (i.e., avoidance/overcontrollers). Those with relatively worse attentional control lack the requisite resources to do this, leading to prolonged attentional engagement with threat stimuli and threat-related attention dysregulation (i.e., maintenance/undercontrollers). Given that attentional control is a limited resource, strategic avoidance of threat information or reduced threat-related attention dysregulation may not be possible among those with relatively higher attentional control when cognitive load is relatively high. To test this hypothesis, the interaction between PTS symptoms, attentional control, and cognitive load was examined as a predictor of threat-related attentional bias and threat-related attention bias variability. Participants (N = 125 undergraduate students) were randomly assigned to high or low load conditions. Participants completed self-report measures of PTS symptoms, a behavioral measure of attentional control, and a novel task that assessed threat-related attentional bias via eye movements and threat-related attention bias variability via button press. The results of a series of hierarchical regressions showed that attentional control moderated the relationship between PTS symptoms and threat-related attention bias variability in the low, but not high, load condition. This moderation effect was not observed for threat-related attentional bias assessed via eye-tracking. Consistent with theory, under conditions of higher cognitive load, overcontrollers may not be able to use attentional control to consistently regulate threat-related attention. Study findings suggest that it may be important to consider contextual factors that increase cognitive load, as well as individual differences in attentional control, when developing attention bias modification interventions to reduce PTS symptomatology.

Individual differences in attentional control explain the differential expression of threat-related attentional bias among those with posttraumatic stress symptomatology and predict symptom maintenance up to one year later

Individual differences in attentional control may explain null findings and inconsistent patterns of threat-related attentional bias (ABT) that are common in the posttraumatic stress disorder (PTSD) literature. At Time 1 (T1), trauma-exposed community participants (N = 89) completed a clinical interview, self-report measures, and an eye-tracking task developed to assess ABT. Participants completed follow-up assessments online 6 (T2) and 12 (T3) months later. Those with higher PTSD symptoms and deficits in attentional control exhibited a pattern of undercontrol, characterized by attention maintenance on threat and increased arousal. In contrast, those with higher PTSD symptoms and relatively better attentional control exhibited a pattern of overcontrol, characterized by threat avoidance and reduced arousal. These effects were specific to threat stimuli. Among PTSD symptom clusters, symptoms of hyperarousal were of central importance to the observed effects. Results from the longitudinal analysis indicate that both of these patterns of ABT are maladaptive, resulting in symptom maintenance at T2 and T3. These results have implications for (a) reconciling tensions between disparate models of ABT (i.e., vigilance-avoidance vs. attention maintenance), (b) precision medicine based approaches to targeting PTSD-related ABT, and (c) understanding the transdiagnostic role that attentional control may play in influencing ABT expression.

Treatment of primary aldosteronism is associated with a reduction in the severity of obstructive sleep apnoea

Obstructive sleep apnoea (OSA) is known to commonly co-exist with primary aldosteronism (PA), but it is unknown if treatment of PA improves sleep apnoea parameters in these patients. We therefore aimed to determine whether specific medical or surgical treatment of PA improves OSA, as measured by the apnoea-hypopnoea index (AHI). We recruited patients undergoing diagnostic workup for PA if they had symptoms suggestive of OSA. Patients with confirmed PA underwent polysomnography (PSG) at baseline and again at least 3 months after specific treatment for PA. Of 34 patients with PA, 7 (21%) had no evidence of OSA (AHI <5), 9 (26%) had mild (AHI ⩾5 and <15), 8 (24%) moderate (AHI ⩾15 and <30) and 10 (29%) severe OSA (AHI ⩾30). Body mass index tertile, neck circumference and 24 h urinary sodium correlated with the AHI. Twenty patients had repeat PSG performed after treatment for PA (mineralocorticoid receptor antagonists in 13 with bilateral PA and adrenalectomy in 7 with unilateral PA). In this group the median (s.d.) AHI reduced from 22.5 (14.7) to 12.3 (12.1) (P=0.02). Neck circumference reduced with PA treatment (41.6 vs 41.2 cm, P=0.012). OSA is common in patients with primary aldosteronism and may improve with specific therapy for this disease. Aldosterone and sodium-mediated fluid retention in the upper airways and neck region may be a potential mechanism for this relationship.

Visual Attention to Dynamic Scenes of Ambiguous Provocation and Children's Aggressive Behavior

Research on biases in attention related to children's aggression has yielded mixed results. Some research suggests that inattention to social cues and reliance on maladaptive social schemas underlie aggression. Other research suggests that maladaptive social schemas lead aggressive individuals to attend to nonhostile cues. The primary objective of this study was to test the proposition that aggression is related to delayed attention to cues followed by selective attention to nonhostile cues after the provocation has occurred. A second objective was to test whether these biases are associated with aggression only when children hold negative social schemas. The eye fixations of 70 children (34 boys, 36 girls; M_age = 11.71 years) were monitored with an eye tracker as they watched video clips of child actors portraying scenes of ambiguous provocation. Aggression was measured using peer-, teacher-, and parent-reports, and children completed a measure of antisocial and prosocial peer beliefs. Aggressive behavior was associated with greater time until fixation on the provocateur among youth who held antisocial peer beliefs. Aggression was also associated with greater time until fixation on an actor displaying empathy for the victim among children reporting low levels of prosocial peer beliefs. After the provocation, aggression was associated with suppressed attention to an amused peer among children who held negative peer beliefs. Increasing attention to cues in a scene of ambiguous provocation, in conjunction with fostering more positive beliefs about peers, may be effective in reducing hostile responding among aggressive youth.

Salt, aldosterone and hypertension

Clinical studies have shown that aldosterone and salt are independently related to hypertension, cardiovascular morbidity and mortality. More recently, studies in humans have demonstrated that, similarly to animals, endogenous aldosterone and dietary salt intake have not only separate, but also combined effects to accelerate target-organ deterioration. The aldosterone-salt interaction has important clinical implications, because combined effects of both can be minimized, if not avoided, by reducing salt intake. This interaction could also be interrupted by blocking the effects of aldosterone, with use of mineralocorticoid receptor antagonists, or by reducing aldosterone effects by adrenalectomy, in patients with aldosterone producing adenoma. Furthermore, aldosterone reduction or blockade may reduce salt appetite.

Factors affecting the aldosterone/renin ratio

Although the aldosterone/renin ratio (ARR) is the most reliable screening test for primary aldo-steronism, false positives and negatives occur. Dietary salt restriction, concomitant malignant or renovascular hypertension, pregnancy and treatment with diuretics (including spironolactone), dihydropyridine calcium blockers, angiotensin converting enzyme inhibitors, and angiotensin receptor antagonists can produce false negatives by stimulating renin. We recently reported selective serotonin reuptake inhibitors lower the ratio. Because potassium regulates aldosterone, uncorrected hypokalemia can lead to false negatives. Beta-blockers, alpha-methyldopa, clonidine, and nonsteroidal anti-inflammatory drugs suppress renin, raising the ARR with potential for false positives. False positives may occur in patients with renal dysfunction or advancing age. We recently showed that (1) females have higher ratios than males, and (2) false positive ratios can occur during the luteal menstrual phase and while taking an oral ethynylestradiol/drospirenone (but not implanted subdermal etonogestrel) contraceptive, but only if calculated using direct renin concentration and not plasma renin activity. Where feasible, diuretics should be ceased at least 6 weeks and other interfering medications at least 2 before ARR measurement, substituting noninterfering agents (e. g., verapamil slow-release±hydralazine and prazosin or doxazosin) were required. Hypokalemia should be corrected and a liberal salt diet encouraged. Collecting blood midmorning from seated patients following 2-4 h upright posture improves sensitivity. The ARR is a screening test only and should be repeated once or more before deciding whether to proceed to confirmatory suppression testing. Liquid chromatography-tandem mass spectrometry aldosterone assays represent a major advance towards addressing inaccuracies inherent in other available methods.

Anger as Seeing Red: Perceptual Sources of Evidence

A class of metaphors links the experience of anger to perceptions of redness. Whether such metaphors have significant implications for understanding perception is not known. In Experiment 1, anger (versus sadness) concepts were primed and it was found that priming anger concepts led individuals to be more likely to perceive the color red. In Experiment 2, anger states were directly manipulated, and it was found that evoking anger led individuals to be more likely to perceive red. Both experiments showed that the observed effects were independent of the actual color presented. These findings extend the New Look, perceptual, metaphoric, and social cognitive literatures. Most importantly, the results suggest that emotion representation processes of a metaphoric type can be extended to the perceptual realm.

Contextual influences on rapid object categorization in natural scenes

The current study aimed to investigate the effects of scene context on rapid object recognition using both behavioral and electrophysiological measures. Participants performed an animal/non-animal go/no-go categorization task in which they had to decide whether or not a flashed scene contained an animal. Moreover, the influence of scene context was manipulated either by retaining, deleting, or phase-randomizing the original scene background. The results of Experiments 1 and 2 showed that participants responded more accurately and quickly to objects appearing with their original scene backgrounds. Moreover, the event-related potential (ERP) data obtained from Experiment 2 showed that the onset latency of the frontal go/no-go ERP difference was delayed for objects appearing with phase-randomized scene backgrounds compared to objects appearing with their original scene backgrounds, providing direct evidence that scene context facilitates object recognition. Additionally, an increased frontal negativity along with a decreased late positive potential for processing objects presented in meaningless scene backgrounds suggest that the categorization task becomes more demanding when scene context is eliminated. Together, the results of the current study are consistent with previous research showing that scene context modulates object processing.

Further study of chromosome 7p22 to identify the molecular basis of familial hyperaldosteronism type II

Familial hyperaldosteronism type II (FH-II) is an inherited form of hyperaldosteronism associated with hypertension in most patients. The mutations that cause FH-II are unknown, but linkage analysis has mapped them to chromosome 7p22. As FH-II is clinically indistinguishable from sporadic primary aldosteronism, a common and treatable condition, unravelling the cause of FH-II has important implications for these sporadic cases. To investigate whether FH-II is caused by large deletions or insertions, we examined the virtual karyotype of four pairs of affected and unaffected individuals using high-density bead chips. We also sequenced the coding regions of five 7p22 candidate genes that were prioritized because of their putative role in cell growth. We found no evidence of single-nucleotide polymorphism (SNP) copy number variation between pairs, and from the widest gap on the chip, chromosome 7p22 deletions or insertions exceeding ∼50 kb in these pedigrees can be excluded. We found 15 SNPs (two of which were novel), but none of them were non-synonymous and segregated with the disease in the FH-II pedigrees. We have been able to exclude large genomic deletions or insertions at 7p22 and refine the candidate gene list for this locus, but the mutations causing FH-II remain elusive.

Episodic Representation of Diagnostic and Non-Diagnostic Object Color

In three experiments, we investigated transsaccadic object file representations. In each experiment, participants moved their eyes from a central fixation cross to a saccade target located between two peripheral objects. During the saccade, this preview display was replaced with a target display containing a single object to be named. On trials in which the target identity matched one of the preview objects, its color either matched or did not match the previewed object color. The results indicated that color changes disrupt perceptual continuity, but only for the class of objects for which color is diagnostic of object identity. When the color is not integral to identifying an object (for example, when the object is a letter or an object without a characteristic color), object continuity is preserved regardless of changes to the object's color. These results suggest that object features that are important for defining the object are incorporated into its episodic representation. Furthermore, the results are consistent with previous work showing that the quality of a feature's representation determines its importance in preserving continuity.

The Effect of Spatial and Nonspatial Contextual Information on Visual Object Memory

Recent research has found visual object memory can be stored as part of a larger scene representation rather than independently of scene context. The present study examined how spatial and nonspatial contextual information modulate visual object memory. Two experiments tested participants' visual memory by using a change detection task in which a target object's orientation was either the same as it appeared during initial viewing or changed. In addition, we examined the effect of spatial and nonspatial contextual manipulations on change detection performance. The results revealed that visual object representations can be maintained reliably after viewing arrays of objects. Moreover, change detection performance was significantly higher when either spatial or nonspatial contextual information remained the same in the test image. We concluded that while processing complex visual stimuli such as object arrays, visual object memory can be stored as part of a comprehensive scene representation, and both spatial and nonspatial contextual changes modulate visual memory retrieval and comparison.

Vasectomy: a long-term study of its effects on testicular endocrine function in man

Plasma testosterone, luteinizing hormone (L.H.) and follicle stimulating (F.S.H.) were measured before operation in 39 males, aged 26 to 53 years with 2 to 5 children, seeking vasectomy for contraceptive purposes. These measurements were repeated at 3 and 12 months after vasectomy. Levels of L.H. at 12 months were significantly higher than pre-vasectomy levels, suggesting some degree of decreased Leydig cell function. However, testosterone and F.S.H. levels were similar at the three sampling times. Continuing yearly measurements for at least 5 years are planned.

Attention to smoking-related and incongruous objects during scene viewing

This study examined the influences of semantic characteristics of objects in real-world scenes on allocation of attention as reflected in eye movement measures. Stimuli consisted of full-color photographic scenes, and within each scene, the semantic salience of two target objects was manipulated while the objects' perceptual salience was kept constant. One of the target objects was either inconsistent or consistent with the scene category. In addition, the second target object was either smoking-related or neutral. Two groups of college students, namely current cigarette smokers (N=18) and non-smokers (N=19), viewed each scene for 10s while their eye movements were recorded. While both groups showed preferential allocation of attention to inconsistent objects, smokers also selectively attended to smoking-related objects. Theoretical implications of the results are discussed.

Selective attention during scene perception: evidence from negative priming

In two experiments, we examined the role of semantic scene content in guiding attention during scene viewing. In each experiment, performance on a lexical decision task was measured following the brief presentation of a scene. The lexical decision stimulus named an object that was either present or not present in the scene. The results of Experiment 1 revealed no priming from inconsistent objects (whose identities conflicted with the scene in which they appeared), but negative priming from consistent objects. The results of Experiment 2 indicated that negative priming from consistent objects occurs only when inconsistent objects are present in the scenes. Together, the results suggest that observers are likely to attend to inconsistent objects, and that representations of consistent objects are suppressed in the presence of an inconsistent object. Furthermore, the data suggest that inconsistent objects draw attention because they are relatively difficult to identify in an inappropriate context.

Mycophenolate mofetil use is associated with decreased risk of late acute rejection in adult liver transplant recipients

Mycophenolate mofetil (MMF) used in a triple-drug regimen has been shown to decrease acute rejection rates, compared to a double-drug regimen. The impact of MMF on late acute rejection (LAR) episodes has not been well described. To investigate the risk of LAR (rejection > or = 6 months post-transplantation) data from the Scientific Registry of Transplant Recipients (SRTR) were used. We studied adult primary liver transplant recipients transplanted between June 1, 1995, and April 30, 2004, with hepatitis C virus (HCV) (n = 3356), hepatitis B virus (HBV) (n = 550) or a nonviral (n = 5740) primary cause of liver disease who were recorded as receiving continuous 3-(MMF + Tacro + steroids) versus 2-drug (Tacro + steroids) therapy for at least 6 months immediately post transplantation. Kaplan-Meier analysis showed significantly lower LAR rates 4 years post-transplant in 3- versus 2-drug HCV, HBV and nonviral disease patients. Multivariate regression confirmed 3- versus 2-drug therapy to be associated with a decreased risk of LAR. Late graft survival was significantly lower at 4 years post-transplant for patients with LAR 6-12 months post-transplantation versus patients with early rejection (78.0% vs. 87.0%, p < 0.001) and no rejection (88.1%, p < 0.001). Three-drug versus 2-drug therapy for a minimum of 6 months may offer a better treatment strategy to avoid the consequences and expense of LAR episodes.

Mycophenolate mofetil reduces intimal thickness by intravascular ultrasound after heart transplant: reanalysis of the multicenter trial

The mycophenolate mofetil (MMF) trial involved 650 heart transplant patients from 28 centers who received MMF or azathioprine (AZA), both in combination with cyclosporine and corticosteroids. Baseline and 1-year intravascular ultrasound (IVUS) were performed in 196 patients (102 MMF and 94 AZA) with no differences between groups in IVUS results analyzed by morphometric analysis (average of 10 evenly spaced sites, without matching sites between studies). Baseline to first-year IVUS data can also be analyzed by site-to-site analysis (matching sites between studies), which has been reported to be more clinically relevant. Therefore, we used site-to-site analysis to reanalyze the multicenter MMF IVUS data.

RESULTS

IVUS images were reviewed and interpretable in 190 patients (99 MMF and 91 AZA) from the multicenter randomized trial. The AZA group compared to the MMF group had a larger number of patients with first-year maximal intimal thickness (MIT)>or=0.3 mm (43% vs. 23%, p=0.005), a greater decrease in the mean lumen area (p=0.02) and a decrease in the mean vessel area (the area actually increased in the MMF group, p=0.03).

CONCLUSION

MMF-treated heart transplant patients compared to AZA-treated patients, both concurrently on cyclosporine and corticosteroids, in this study have significantly less progression of first-year intimal thickening.

Addition of MMF to dual immunosuppression does not increase the risk of malignant short-term death after liver transplantation

Immunosuppression is often incriminated for the increased risk of post-transplant malignancies. To examine whether triple- (MMF+Tacro+CS) versus dual-drug therapy (Tacro+CS) is associated with an increased incidence of malignancy, or death due to malignancy, data from a large registry of liver transplant recipients were analyzed. Data from adult primary liver recipients reported to the Scientific Registry of Transplant Recipients between June 1, 1995, and April 30, 2004, and recorded at transplant on triple-drug (n = 9180) or dual-drug (n = 10 099) therapy were included. Kaplan-Meier survival analysis showed no significant differences in death due to malignancy 4 years post-transplantation between the treatment groups. Multivariable analysis using Cox proportional hazard models confirmed no differences in risk of death due to malignancy between the groups (HR: 0.83, p = 0.107). Incidence of any post-transplant malignancy was also not significantly different. Older recipient age and cause of liver disease were significantly associated with an increased risk of malignancy-related death. These data utilizing relatively short follow-up suggest the addition of MMF to Tacro+CS at transplant is not associated with death due to malignancy, at least in the short term. Individual recipient factors appear to be important risk factors for malignancy-related death; elucidating these risk factors can assist in identifying who should be monitored most aggressively for post-transplant malignancies.

The emergence of chemical genomics in drug discovery

The interaction of small organic molecules with proteins and other macromolecules is fundamental to drug action. Chemical genomics employs a combination of chemistry, genomics and informatics to study these drug-target interactions in a systematic and global manner in order to improve the efficiency of the drug discovery process.

Daclizumab is associated with decreased rejection and improved patient survival in renal transplant recipients

The present study investigated the safety of induction therapy with daclizumab (compared with no induction treatment), in adult renal transplant patients reported to the Scientific Registry of Transplant Recipients (SRTR) database between January 1, 1998 and July 27, 2003. Patients who were discharged from the hospital on mycophenolate mofetil, azathioprine, or sirolimus were divided into two groups: induction treatment with daclizumab (n = 8203) and no induction treatment (n = 25,368). Patient survival, death due to infection and death due to malignancy were evaluated at 1 and 3 yr post-transplantation. Rejection and graft survival were also examined. Kaplan-Meier and Cox regression models were used to evaluate outcomes. No significant differences were found between patients treated with daclizumab compared with patients who received no induction therapy for death due to infection or malignancy at 1 and 3 yr post-transplantation. Patients treated with daclizumab (compared with no induction treatment) had statistically significantly better survival rates at 1 (96.9% vs. 96.2%, p = 0.003) and 3 yr (92.4% vs. 91.4%, p = 0.004) although absolute differences were minimal. This was confirmed in the multivariable Cox regression analysis for patient death at 1 (HR = 0.77, p < 0.001) and 3 yr (HR = 0.83, p = 0.001) post-transplantation. Patients treated with daclizumab compared to no induction had lower rejection rates at 1 (13.1% vs. 17.3%, p < 0.001) and 3 yr post-transplantation (16.7% vs. 21.3%, p < 0.001). Cox regression confirmed a decreased risk for rejection at 1 (HR = 0.74, p < 0.001) and 3 yr (HR = 0.75, p < 0.001). Treatment with daclizumab was associated with reduced risk for graft loss at 1 (HR = 0.82, p < 0.001) and 3 years (HR = 0.86, p < 0.001). In conclusion, daclizumab was associated with a significantly reduced risk for rejection and graft loss compared with no induction treatment, and improved patient survival. In addition, daclizumab was not associated with an increase in risk of death due to infection or malignancy, when compared with no induction therapy. These findings demonstrate the short and long-term safety and efficacy of daclizumab in patients transplanted between January 1998 and July 2003.

Mycophenolate mofetil combination therapy improves long-term outcomes after liver transplantation in patients with and without hepatitis C

To evaluate the impact of mycophenolate mofetil (MMF) on long-term outcomes of tacrolimus and corticosteroids, we analyzed data reported to the Scientific Registry of Transplant Recipients for 11,670 adult patients (3463 with hepatitis C [HCV]) who underwent primary, single-organ, liver transplantation between 1995 and 2001. Patients who were discharged from the hospital on tacrolimus-based immunosuppression with (n = 4466; n = 1323 HCV) or without MMF (n = 7204; n = 2140 HCV) were included in the analysis. Recipients treated at discharge with MMF, tacrolimus, and corticosteroids had significantly increased patient survival (81.0% vs. 77.0% at 4 years, P < 0.0001) and graft survival (76.4% vs. 72.9%, P < 0.0001), and lower rates of acute rejection (29.0% vs. 33.4%, P < 0.001) as compared to recipients treated at discharge with tacrolimus and corticosteroids alone. A trend toward lower rates of death from infection was observed (6.1% at 4 years for MMF vs. 7.1% at 4 years for tacrolimus and corticosteroids, P = 0.0508), but this result did not reach statistical significance. In multiple regression analyses, MMF triple therapy at discharge was associated with a reduced risk of death (hazard ratio [HR] = 0.77, P < 0.001), graft loss (HR = 0.81, P < 0.001), acute rejection (HR = 0.89, P = 0.002), and death from infectious complications (HR = 0.80, P = 0.007). Outcomes were similar for the cohort with HCV.In conclusion, the addition of MMF at discharge to tacrolimus-based immunosuppression is associated with improved long-term outcomes after liver transplantation in patients with and without HCV.

Daclizumab to prevent rejection after cardiac transplantation

BACKGROUND

Daclizumab, a humanized monoclonal antibody against the interleukin-2 receptor, reduced the risk of rejection without increasing the risk of infection among renal-transplant recipients and, in a single-center trial, among cardiac-transplant recipients. We conducted a multicenter, placebo-controlled, double-blind study to confirm these results in cardiac-transplant patients.

METHODS

We randomly assigned 434 recipients of a first cardiac transplant treated with standard immunosuppression (cyclosporine, mycophenolate mofetil, and corticosteroids) to receive five doses of daclizumab or placebo. The primary end point was a composite of moderate or severe cellular rejection, hemodynamically significant graft dysfunction, a second transplantation, or death or loss to follow-up within six months.

RESULTS

By six months, 104 of 218 patients in the placebo group had reached the primary end point, as compared with 77 of the 216 patients in the daclizumab group (47.7 percent vs. 35.6 percent, P=0.007), a 12.1 percent absolute risk reduction and a 25 percent relative reduction. The rate of rejection was lower in the daclizumab group than in the placebo group (41.3 percent vs. 25.5 percent). Among patients reaching the primary end point, the median time to the end point was almost three times as long in the daclizumab group as in the placebo group during the first 6 months (61 vs. 21 days) and at 1 year (96 vs. 26 days). More patients in the daclizumab group than in the placebo group died of infection (6 vs. 0) when they received concomitant cytolytic therapy.

CONCLUSIONS

Daclizumab was efficacious as prophylaxis against acute cellular rejection after cardiac transplantation. Because of the excess risk of death, concurrent or anticipated use of cytolytic therapy with daclizumab should be avoided.

Emergency anaesthesia in a patient with Gordon's syndrome

Gordon's syndrome is a rare condition characterized by hypertension and hyperkalemia despite normal renal glomerular function. We report the administration of an anaesthetic to one such patient for an urgent surgical procedure. The patient's serum potassium was only marginally raised at the outset of the procedure. During surgery the serum potassium rose significantly, but responded to conventional management. Hyperkalaemia is a specific electrolyte disturbance that has numerous implications for the administration of an anaesthetic. Most importantly, there is a danger that further acute elevations may occur, caused by the surgery, the anaesthetic, or the condition itself

Differential effects of donor age in liver transplant recipients infected with hepatitis B, hepatitis C and without viral hepatitis

The variable impact of specific risk factors on survival outcomes based on pre-transplantation diagnosis was analyzed in adult liver transplant recipients reported to the Scientific Registry of Transplant Recipients: 778 with hepatitis B (HBV), 3463 with hepatitis C (HCV) and 7429 without viral hepatitis. Graft and patient survival for the HBV and no viral hepatitis groups did not differ significantly. The HCV group had significantly lower graft (p = 0.0019) and patient survival (p < 0.0001) than the no viral hepatitis group. Patient survival was significantly lower (p = 0.0011) for HCV compared to HBV patients; differences in graft survival approached significance (p = 0.0561). Donor age, which was not a risk factor in patients with HBV, was the strongest predictor of graft loss and death in patients with HCV, starting with donors >40 years. Donor age >60 years was the strongest predictor of graft loss and death in patients without viral hepatitis. The risks of graft loss and death were reduced for patients on tacrolimus-based immunosuppression with mycophenolate mofetil, regardless of disease etiology. There are clear differences in risk factors for poor outcomes based on underlying liver disease, particularly with regard to the impact of donor age.

Mycophenolate mofetil vs. azathioprine is associated with decreased acute rejection, late acute rejection, and risk for cardiovascular death in renal transplant recipients with pre-transplant diabetes

Outcomes specifically in mycophenolate mofetil (MMF)-treated diabetic renal transplant patients have not been previously reported. This study compared acute rejection (AR), late acute rejection (LAR), patient survival [and specifically death from cardiovascular (CV), infectious and malignant causes], incidence of post-transplant malignancies, and graft loss in MMF- or azathioprine (AZA)-treated renal transplant patients with pre-transplant diabetes. Outcomes were compared between MMF- (n = 14 144) and AZA- (n = 3001) treated diabetic patients using the Scientific Registry of Transplant Recipients data on all U.S. adult renal transplants performed between 1995 and 2002. Statistical analyses included Kaplan-Meier survival analysis, Cox multivariable regression and chi-square tests. MMF patients had less AR compared with AZA-treated patients (23.5% vs. 28.3%, p < 0.001) and less risk for LAR over 4 yr [hazard ratio (HR): 0.64, 95% CI 0.44, 0.92; p = 0.02]. While time to any-cause death did not differ between the groups, MMF treatment was associated with a 20% decreased risk of CV death (HR: 0.80, 95% CI 0.67, 0.97; p = 0.020) compared with AZA treatment. MMF patients also had a lower incidence of malignancies than AZA patients (2.2% vs. 3.7%, p < 0.001). These results suggest treatment with MMF compared with treatment with AZA in diabetic transplant patients is associated with less AR, less risk of LAR, a decreased risk of CV death, and a lower incidence of malignancies.

Daclizumab is Associated With Decreased Rejection and No Increased Mortality in Cardiac Transplant Patients Receiving MMF, Cyclosporine, and Corticosteroids

BACKGROUND

Sparse published data exist on outcomes in daclizumab-treated cardiac transplant patients. One trial observed an increased mortality risk 6 and 12 months posttransplant in patients receiving daclizumab plus mycophenolate mofetil (MMF), cyclosporine, and steroids. This study further investigates the safety profile of daclizumab with this same immunosuppressive regimen from a large registry.

METHODS

Data obtained at hospital discharge on all adult cardiac transplants performed in the USA between January 1998 and October 2003 for patients receiving MMF plus cyclosporine and steroids were accessed from the Scientific Registry of Transplant Recipients. Patients were selected based on induction treatment: daclizumab (n = 684) or no induction (n = 2525). Outcomes were evaluated at 6 months, 12 months, and 3 years posttransplant. Univariate Kaplan-Meier and multivariate Cox models were used to evaluate the effect of treatment on outcomes. Patient survival and infectious death were the primary endpoints. Secondary endpoints included rejection within the first year posttransplant (acute rejection; AR) and total rejection episodes over time. The two treatment groups shared similar demographics and transplant procedure details.

RESULTS

Daclizumab (vs no induction) patients had no increased risk of patient death nor infectious death. Daclizumab patients had a lower incidence of AR at 6 months (P = .005) and 12 months (P < .001); the adjusted risk for AR at 12 months (hazards ratio [HR] = 0.77; P = .89) and over 3 years (HR 0.83, P = .006) was also lower in daclizumab-treated patients.

CONCLUSIONS

In cardiac transplant patients, daclizumab (vs no induction) does not result in increased mortality or infectious death, and is associated with a lower incidence of AR.

Differential effects of donor age in liver transplant recipients infected with hepatitis B, hepatitis C and without viral hepatitis

The variable impact of specific risk factors on survival outcomes based on pre-transplantation diagnosis was analyzed in adult liver transplant recipients reported to the Scientific Registry of Transplant Recipients: 778 with hepatitis B (HBV), 3463 with hepatitis C (HCV) and 7429 without viral hepatitis. Graft and patient survival for the HBV and no viral hepatitis groups did not differ significantly. The HCV group had significantly lower graft (p = 0.0019) and patient survival (p < 0.0001) than the no viral hepatitis group. Patient survival was significantly lower (p = 0.0011) for HCV compared to HBV patients; differences in graft survival approached significance (p = 0.0561). Donor age, which was not a risk factor in patients with HBV, was the strongest predictor of graft loss and death in patients with HCV, starting with donors >40 years. Donor age >60 years was the strongest predictor of graft loss and death in patients without viral hepatitis. The risks of graft loss and death were reduced for patients on tacrolimus-based immunosuppression with mycophenolate mofetil, regardless of disease etiology. There are clear differences in risk factors for poor outcomes based on underlying liver disease, particularly with regard to the impact of donor age.

Mycophenolate mofetil vs azathioprine in a large population of elderly renal transplant patients

BACKGROUND

Mycophenolate mofetil (MMF) has been shown to decrease acute rejection episodes after kidney transplantation, and has been associated with better graft and patient survival vs azathioprine (AZA). Previous studies reported a higher risk of death due to infection in elderly recipients treated with MMF-based immunosuppression.

METHODS

We analysed 5069 elderly ( > 65 years of age) primary renal allograft recipients treated with either MMF or AZA reported to the Scientific Registry of Transplant Recipients between 1988 and 2000, and compared rates of acute rejection, late acute rejection, graft survival, death-censored graft survival, patient survival and death with a functioning graft.

RESULTS

In Cox proportional hazard models, MMF was associated with lower rates of late acute rejection with 12 (RR = 0.72, P = 0.11) and 24 months (RR = 0.50, P = 0.028) of continuous therapy. In univariate analysis (Kaplan-Meier), MMF was associated with improved patient (P = 0.0003) and graft (P<0.0001) survival vs AZA, and trends toward improved patient and graft survival in multivariate analyses.

CONCLUSIONS

These findings demonstrate the efficacy of MMF-based immunosuppression in elderly transplant recipients and do not suggest an increased risk of death compared to treatment with AZA.

Sirolimus with neoral versus mycophenolate mofetil with neoral is associated with decreased renal allograft survival

To evaluate the association between a regimen of cyclosporine microemulsion (CsA) + sirolimus (Rapa) treatment versus CsA and mycophenolate mofetil (MMF) and renal allograft survival, we analyzed 23 016 primary recipients reported to the Scientific Registry of Transplant Recipients between January 1, 1998 and July 26, 2003. Univariate Kaplan-Meier analysis and multivariate Cox proportional hazard models correcting for demographic and clinical covariates were used to estimate the relative risks for CsA+Rapa versus CsA+MMF-treated patients reaching study endpoints. Subgroup analyses were conducted for recipient ethnicity and donor type. CsA+Rapa was associated with significantly lower graft survival (74.6% vs. 79.3% at 4 years, p = 0.002) and death-censored graft survival (83.7% vs. 87.2%, p = 0.003) compared to CsA+MMF. In multivariate analyses, CsA+Rapa was associated with a significantly increased risk for graft loss, death-censored graft loss and decline in renal function (HR = 1.22, p = 0.002; HR = 1.22, p = 0.018 and HR = 1.25, p < 0.001, respectively). Similar results were obtained in recipient ethnicity and donor type subgroups. In summary, CsA+Rapa was associated with significantly worse graft survival and death-censored graft survival compared to CsA+MMF, and likely reflects full-dose CsA +Rapa. Outcomes regarding alternative strategies of Rapa utilization with reduced CsA, with alternative agents or with no calcineurin inhibitor cannot be extrapolated from these data.

Attentional Allocation During the Perception of Scenes

Semantic influences on attention during the 1st fixation on a scene were explored in 3 experiments. Subjects viewed briefly presented scenes; following scene presentation, a spatial probe was presented at the location of an object whose identity was consistent or inconsistent with the scene category. Responses to the probe served as an index of attention. The results of Experiment 1 suggest that within approximately 150 ms of scene onset, subjects attend preferentially to inconsistent objects. The results of Experiment 2, in which additional scene durations were used, confirm the presence of an inconsistent-object advantage that emerges within approximately 150 ms. Finally, the results of Experiment 3 demonstrate that the inconsistent-object advantage does not reflect strategic allocation of attention to likely probe locations. Implications of the results for scene perception and exploration are discussed.

Mycophenolate mofetil versus azathioprine therapy is associated with a significant protection against long-term renal allograft function deterioration

BACKGROUND

To evaluate the association of long-term continuous mycophenolate mofetil (MMF) versus azathioprine (AZA) therapy and renal allograft function, as measured by the slope of reciprocal creatinine, we analyzed 49,666 primary renal allograft recipients reported to the United States Renal Data System between October 31, 1988 and June 30, 1998.

METHODS

The primary study endpoint was defined as a greater than 20% decrease below a 6-month baseline of 1/serum creatinine (SCr) (slope of reciprocal creatinine) at or beyond 1 year after transplantation. A secondary endpoint was defined as reaching an SCr value greater than 1.6 mg/dL. Univariate Kaplan-Meier analysis and multivariate Cox proportional hazard models were used to investigate the risk of reaching the study endpoints. Multivariate analyses were corrected for potential confounding covariates.

RESULTS

According to the Cox proportional hazard model, 12-month continued therapy of MMF versus AZA was associated with a protective effect against declining renal function, as measured by the slope of reciprocal creatinine (relative risk [RR]=0.84, confidence interval 0.78-0.91, P<0.001). For 24-month continued therapy of MMF versus AZA, MMF was associated with a further decreased risk for a decline in renal function (RR=0.66, confidence interval=0.57-0.77, P<0.001). Furthermore, MMF was associated with a protective effect against reaching the SCr threshold of 1.6 mg/dL (RR=0.80, P<0.001) beyond 12 months posttransplantation.

CONCLUSIONS

Continuous use of MMF versus AZA was associated with a protective effect against declining renal function beyond 1 year after transplantation. Further study is needed to confirm that continued MMF therapy is protective against long-term deterioration in renal function.

Long-term use of mycophenolate mofetil is associated with a reduction in the incidence and risk of late rejection

To evaluate the association of long-term continuous (minimum 1 year) mycophenolate mofetil (MMF) vs. azathioprine (AZA) therapy with the incidence of late acute rejection, we analyzed 47 693 primary renal allograft recipients reported to the United States Renal Data System between 1988 and 1998. The primary study endpoint was acute rejection beyond 1 year after transplantation. Univariate Kaplan-Meier analysis and multivariate Cox proportional hazard models were used to investigate the risk of reaching the study endpoints. All multivariate analyses were corrected for potential confounding covariates. Mycophenolate mofetil was associated with a 65% decreased risk of developing late acute rejection as compared to AZA (RR = 0.35, CI 0.27-0.45, p < 0.001). The incidence of acute rejection episodes at 2 and 3 years post-transplantation was significantly lower in the MMF group (0.9% at 2 years, 1.1% at 3 years) than the AZA group (6.1% at 2 years, 9.3% at 3 years). In the primary vs. repeat late rejection analysis, MMF patients exhibited a decreased late acute rejection risk of 72% (RR = 0.28, p < 0.001) and 60%, respectively (RR = 0.40, p < 0.001). In African Americans, the late acute rejection risk was 70% lower in MMF patients than AZA patients (RR = 0.30, p < 0.001). Further study is indicated to determine the optimal duration of MMF therapy after renal allograft transplantation.

Familial varieties of primary aldosteronism

1. Improved approaches to screening and diagnosis have revealed primary aldosteronism (PAL) to be much more common than previously thought, with most patients normokalaemic. The spectrum of this disorder has been further broadened by the study of familial varieties. 2. Familial hyperaldosteronism type I (FH-I) is a glucocorticoid-remediable form of PAL caused by the inheritance of an adrenocorticotrophic hormone (ACTH)- regulated, hybrid CYP11B1/CYP11B2 gene. Diagnosis has been greatly facilitated by the advent of genetic testing. The severity of hypertension varies widely in FH-I, even among members of the same family, and has demonstrated relationships with gender, degree of biochemical disturbance and hybrid gene crossover point position. Hormone "day curve" studies show that the hybrid gene dominates over wild-type CYP11B2 in terms of aldosterone regulation. This may be due, in part, to a defect in wild-type CYP11B2-induced aldosterone production. Control of hypertension in FH-I requires only partial suppression of ACTH and much smaller glucocorticoid doses than previously recommended. 3. Familial hyperaldosteronism type II (FH-II) is not glucocorticoid remediable and is not associated with the hybrid gene mutation. Familial hyperaldosteronism type II is clinically, biochemically and morphologically indistinguishable from apparently non-familial PAL. Linkage studies in one informative family did not show segregation of FH-II with the CYP11B2, AT1 or MEN1 genes, but a genome-wide search has revealed linkage with a locus in chromosome 7. As has already occurred in FH-I, elucidation of causative mutations is likely to facilitate earlier detection of PAL.

Familial hyperaldosteronism

Primary aldosteronism (PAL) may be as much as ten times more common than has been traditionally thought, with most patients normokalemic. The study of familial varieties has facilitated a fuller appreciation of the nature and diversity of its clinical, biochemical, morphological and molecular aspects. In familial hyperaldosteronism type I (FH-I), glucocorticoid-remediable PAL is caused by inheritance of an ACTH-regulated, hybrid CYP11B1/CYP11B2 gene. Genetic testing has greatly facilitated diagnosis. Hypertension severity varies widely, demonstrating relationships with gender, affected parent's gender, urinary kallikrein level, degree of biochemical disturbance and hybrid gene crossover point position. Analyses of aldosterone/PRA/cortisol 'day-curves' have revealed that (1) the hybrid gene dominates over wild type CYP11B2 in terms of aldosterone regulation and (2) correction of hypertension in FH-I requires only partial suppression of ACTH, and much smaller glucocorticoid doses than those previously recommended. Familial hyperaldosteronism type II is not glucocorticoid-remediable, and is clinically, biochemically and morphologically indistinguishable from apparently sporadic PAL. In one informative family available for linkage analysis, FH-II does not segregate with either the CYP11B2, AT1 or MEN1 genes, but a genome-wide search has revealed linkage with a locus in chromosome 7. As has already occurred in FH-I, elucidation of causative mutations is likely to facilitate earlier detection of PAL and other curable or specifically treatable forms of hypertension.

Primary aldosteronism: are we diagnosing and operating on too few patients?

Many cases of potentially curable primary aldosteronism are currently likely to be diagnosed as essential hypertension unless screening tests based on suppression of renin are carried out in all hypertensive patients. More than half of the patients with primary aldosteronism detected in this way have normal circulating potassium levels, so measurement of potassium is not enough to exclude primary aldosteronism. When primary aldosteronism is diagnosed, fewer than one-third of patients are suitable for surgery as initial treatment, but this still represents a significant percentage of hypertensive patients. After excluding glucocorticoid-suppressible primary aldosteronism, adrenal venous sampling is essential to detect unilateral production of aldosterone and diagnose angiotensin-responsive aldosterone-producing adenoma. One cannot rely on the computed tomography scan. If all hypertensive patients are screened for primary aldosteronism and the workup is continued methodically in those with a positive screening test, patients with unilateral overproduction of aldosterone who potentially can be cured surgically are not denied the possibility of cure.

Executive control of visual attention in dual-task situations

A theory of executive control is presented that proposes that executive processes control subordinate processes by manipulating their parameters, reconfiguring them to respond in accord with the current task set. It adopts C. Bundesen's (1990) theory of visual attention (TVA) and R. M. Nosofsky and T. J. Palmeri's (1997) exemplar-based random walk (EBRW) as the theory of subordinate processes. It assumes that a task set is a set of TVA and EBRW parameters sufficient to perform a task and that set switching involves changing those parameters. The theory solves 2 computational problems that emerge in dual-task situations: the binding problem and the serial order problem. It can perform dual tasks in series or in parallel but prefers the serial strategy because it is faster and it solves the binding problem naturally. The theory accounts for concurrence cost, set-switching cost, crosstalk between tasks, and the modulation of crosstalk by task set.

Mammalian GFRalpha -4, a divergent member of the GFRalpha family of coreceptors for glial cell line-derived neurotrophic factor family ligands, is a receptor for the neurotrophic factor persephin

Four members of the glial cell line-derived neurotrophic factor family have been identified (GDNF, neurturin, persephin, and enovin/artemin). They bind to a specific membrane-anchored GDNF family receptor as follows: GFRalpha-1 for GDNF, GFRalpha-2 for neurturin, GFRalpha-3 for enovin/artemin, and (chicken) GFRalpha-4 for persephin. Subsequent signaling occurs through activation of a common transmembrane tyrosine kinase, cRET. GFRalpha-4, the coreceptor for persephin, was previously identified in chicken only. We describe the cloning and characterization of a mammalian persephin receptor GFRalpha-4. The novel GFRalpha receptor is substantially different in sequence from all known GFRalphas, including chicken GFRalpha-4, and lacks the first cysteine-rich domain present in all previously characterized GFRalphas. At least two different GFRalpha-4 splice variants exist in rat tissues, differing at their respective COOH termini. GFRalpha-4 mRNA is expressed at low levels in different brain areas in the adult as well as in some peripheral tissues including testis and heart. Recombinant rat GFRalpha-4 variants were expressed in mammalian cells and shown to be at least partially secreted from the cells. Persephin binds specifically and with high affinity (K(D) = 6 nm) to the rat GFRalpha-4 receptor, but no cRET activation could be demonstrated. Although the newly characterized mammalian GFRalpha-4 receptor is structurally divergent from previously characterized GFRalpha family members, we suggest that it is a mammalian orthologue of the chicken persephin receptor. This discovery will allow a more detailed investigation of the biological targets of persephin action and its potential involvement in diseases of the nervous system.

Sporadic and familial pheochromocytomas are associated with loss of at least two discrete intervals on chromosome 1p

Pheochromocytomas are tumors of the adrenal medulla originating in the chromaffin cells derived from the neural crest. Ten % of these tumors are associated with the familial cancer syndromes multiple endocrine neoplasia type 2, von Hippel-Lindau disease (VHL), and rarely, neurofibromatosis type 1, in which germ-line mutations have been identified in RET, VHL, and NF1, respectively. In both the sporadic and familial form of pheochromocytoma, allelic loss at 1p, 3p, 17p, and 22q has been reported, yet the molecular pathogenesis of these tumors is largely unknown. Allelic loss at chromosome 1p has also been reported in other endocrine tumors, such as medullary thyroid cancer and tumors of the parathyroid gland, as well as in tumors of neural crest origin including neuroblastoma and malignant melanoma. In this study, we performed fine structure mapping of deletions at chromosome 1p in familial and sporadic pheochromocytomas to identify discrete regions likely housing tumor suppressor genes involved in the development of these tumors. Ten microsatellite markers spanning a region of approximately 70 cM (1pter to 1p34.3) were used to screen 20 pheochromocytomas from 19 unrelated patients for loss of heterozygosity (LOH). LOH was detected at five or more loci in 8 of 13 (61%) sporadic samples and at five or more loci in four of five (80%) tumor samples from patients with multiple endocrine neoplasia type 2. No LOH at 1p was detected in pheochromocytomas from two VHL patients. Analysis of the combined sporadic and familial tumor data suggested three possible regions of common somatic loss, designated as PC1 (D1S243 to D1S244), PC2 (D1S228 to D1S507), and PC3 (D1S507 toward the centromere). We propose that chromosome 1p may be the site of at least three putative tumor suppressor loci involved in the tumorigenesis of pheochromocytomas. At least one of these loci, PC2 spanning an interval of <3.8 cM, is likely to have a broader role in the development of endocrine malignancies.

Effects of pi* <-- n Excitation in 4-Cyclopentene-1,3-Dione

The weak visible absorption spectrum of 4-cyclopentene-1,3-dione has been photographed near room temperature and assigned to the A(1)B(1) <-- X(1)A(1), pi* <-- n transition with origin at 22 000 cm(-1). A few weak bands near 28 465 cm(-1) have been assigned to a second (1)A(2) pi* <-- n transition. The effects of excitation are delocalized over the highly conjugated molecule, the most important geometrical change upon excitation being an in-plane distortion of the five-membered ring. Many sequences are observed in the ring-puckering and twisting modes, both of which increase substantially in wavenumber upon excitation. Possible reasons for this dramatic increase in the forces favoring ring planarity are discussed. Copyright 2000 Academic Press.

A novel genetic locus for low renin hypertension: familial hyperaldosteronism type II maps to chromosome 7 (7p22)

Familial hyperaldosteronism type II (FH-II) is caused by adrenocortical hyperplasia or aldosteronoma or both and is frequently transmitted in an autosomal dominant fashion. Unlike FH type I (FH-I), which results from fusion of the CYP11B1 and CYP11B2 genes, hyperaldosteronism in FH-II is not glucocorticoid remediable. A large family with FH-II was used for a genome wide search and its members were evaluated by measuring the aldosterone:renin ratio. In those with an increased ratio, FH-II was confirmed by fludrocortisone suppression testing. After excluding most of the genome, genetic linkage was identified with a maximum two point lod score of 3.26 at theta=0, between FH-II in this family and the polymorphic markers D7S511, D7S517, and GATA24F03 on chromosome 7, a region that corresponds to cytogenetic band 7p22. This is the first identified locus for FH-II; its molecular elucidation may provide further insight into the aetiology of primary aldosteronism.

Binding of GDNF and neurturin to human GDNF family receptor alpha 1 and 2. Influence of cRET and cooperative interactions

The members of the glial cell line-derived neurotrophic factor (GDNF) family signal via binding to the glycosyl phosphatidylinositol-anchored membrane proteins, the GDNF family receptors alpha (GFRalpha), and activation of cRET. We performed a detailed analysis of the binding of GDNF and neurturin to their receptors and investigated the influence of cRET on the binding affinities. We show that the rate of dissociation of (125)I-GDNF from GFRalpha1 is increased in the presence of 50 nm GDNF, an effect that can be explained by the occurrence of negative cooperativity. Scatchard plots of the ligand concentration binding isotherms reveal a pronounced downward curvature at low (125)I-GDNF concentrations suggesting the presence of positive cooperativity. This effect is observed in the range of GDNF concentrations responsible for biological activity (1-20 pm) and may have an important role in cRET-independent signaling. A high affinity site with a K(D) of 11 pm for (125)I-GDNF is detected only when GFRalpha1 is co-expressed with cRET at a DNA ratio of 1:3. These results suggest an interaction of GFRalpha1 and cRET in the absence of GDNF and demonstrate that the high affinity binding can be measured only when cRET is present.

Primary aldosteronism: learning from the study of familial varieties

Primary aldosteronism (PAL) has been traditionally regarded as a rare cause of hypertension and not worth looking for in the absence of hypokalemia. However, the availability of the aldosterone/renin ratio as a screening test and its application to a wider population of hypertensives has resulted in a marked increase in detection rate, suggesting that PAL is common, with most patients being normokalemic. The spectrum of PAL has been expanded further by the study of familial varieties, in which family screening efforts have permitted the recognition of earlier, sometimes even pre-clinical, stages of disease. Familial hyperaldosteronism type I(FH-I) In FH-I, inheritance of a 'hybrid' 11beta-hydroxylase/aldosterone synthase gene causes adrenocorticotrophic hormone (ACTH)-regulated aldosterone and 'hybrid steroid' (18hydroxy-cortisol and 18-oxo-cortisol) overproduction. Genetic testing, by Southern blot or polymerase chain reaction-based techniques, has greatly facilitated detection, being more convenient and more reliable than dexamethasone suppression testing, and has led to a fuller appreciation of the marked phenotypic variability in this disorder. The demonstration of excessive, abnormally regulated aldosterone production in normotensive subjects with FH-I suggests that absence of hypertension in such individuals cannot merely be attributed to lack of expression of the hybrid gene. Determinants of hypertension severity may include patient gender, gender of affected parent, degree of hybrid gene expression, and interactions with other genetic and environmental factors. Detailed biochemical studies, including analyses of aldosterone/PRA/cortisol 'day-curve' levels, have led to a fuller understanding of aldosterone regulation both before and in response to glucocorticoid treatment in this condition, and prompted a re-examination of current approaches to treatment Unless ACTH is completely suppressed by glucocorticoid treatment, the hybrid gene dominates over the wild-type aldosterone synthase genes in terms of aldosterone production, both in untreated and treated FH-I. This may in part be due to an abnormality affecting the functional expression of the 'wild-type' genes. Demonstration of persisting hybrid gene expression in patients rendered normotensive by very low doses of glucocorticoids suggests that currently recommended doses, aimed at normalizing aldosterone regulation (rather than blood pressure), may be too high, and may therefore place patients at unnecessary risk of developing Cushingoid side effects. Familial hyperaldosteronism type II (FH-II) Like FH-I, FH-II is associated with hyperaldosteronism and probable autosomal dominant inheritance. Unlike FH-I, hyperaldosteronism in FH-II is not dexamethasone suppressible, and is not associated with the hybrid gene mutation. Detection of adrenal mass lesions, which are frequently (17 of 57 patients in the Greenslopes Hospital series) responsible for PAL in FH-II, does not help to differentiate FH-II from FH-I, since mass lesions may also be common in that condition (detected in seven of 21 patients). Biochemically and morphologically, FH-II is indistinguishable from apparently non-familial PAL, and demonstrates similar variability even among individuals of the same family. In one informative family available for linkage analysis, FH-II does not segregate with either the AT1 gene or the CYP11B2 gene, or any other genetic defect in the chromosome 8q21-8qtel region. A genome-wide search is in progress. As has already occurred in FH-I, the elucidation of underlying genetic mutations in FH-II is likely to facilitate early detection, thereby helping to broaden its spectrum and to permit close follow-up and appropriately timed institution of specific therapy, and wider detection among patients with hypertension of potentially curable or specifically treatable forms.

Treatment of familial hyperaldosteronism type I: only partial suppression of adrenocorticotropin required to correct hypertension

In familial hyperaldosteronism type I, inheritance of a hybrid 11beta-hydroxylase/aldosterone synthase gene leads to ACTH-regulated overproduction of aldosterone (causing hypertension) and of "hybrid" steroids, 18-hydroxy- and 18-oxo-cortisol. To determine whether complete suppression of the hybrid gene is necessary to normalize blood pressure, we sought evidence of persisting expression in eight patients who were rendered normotensive for 1.3-4.5 yr by glucocorticoid treatment. At the time of the study, six patients were receiving dexamethasone (0.125-0.25 mg/day) and two patients were taking prednisolone (2.5 or 5 mg/day). Urinary 18-oxo-cortisol levels during treatment demonstrated close correlation with mean "day curve" (blood collected every 2 h for 24 h) cortisol (r = 0.74), consistent with regulation by ACTH. Although urinary 18-oxo-cortisol levels were lower during than before treatment (mean 12.6 +/- 2.4 SEM vs. 35.0 +/- 5.6 nmol/mmol creatinine; P < 0.01), they remained above normal (0.8-5.2 nmol/mmol creatinine) in all eight patients. Although mean upright plasma potassium levels during treatment were higher, aldosterone levels lower, PRA levels higher, and aldosterone to PRA ratios lower than before treatment, PRA levels were uncorrected (< 13 pmol/L x min) and aldosterone to PRA ratios were uncorrected (>65) during treatment in four patients. For each of the eight patients, day curve aldosterone levels during treatment correlated more tightly with cortisol (mean r for the eight patients, 0.87 +/- 0.05 SEM) than with PRA (mean r = 0.36 +/- 0.10 SEM). Hence, control of hypertension by glucocorticoid treatment was associated, in all patients, with only partial suppression of ACTH-regulated hybrid steroid and aldosterone production. Normalization of urinary hybrid steroid levels and abolition of ACTH-regulated aldosterone production is not a requisite for hypertension control and, if used as a treatment goal, may unnecessarily increase the risk of Cushingoid side effects.