A feasibility, randomised controlled trial of Club Connect: a group-based healthy brain ageing cognitive training program for older adults with major depression within an older people's mental health service

BACKGROUND

Using the RE-AIM (reach, effectiveness, adoption, implementation, maintenance) framework, we outline steps taken to implement an evidence-based cognitive training program, Club Connect, in older adults with major depressive disorder in an Older People's Mental Health Service in Sydney, Australia. The primary aim was to explore feasibility (or 'reach'), tolerability (or 'implementation'), and acceptability (or 'adoption'). The secondary aim was to explore the most sensitive clinical outcomes and measurement tools (i.e. 'effectiveness') to inform a formal randomised controlled trial, and to explore the healthcare resources used (i.e. costs) to assist decision-making by health care managers and policy-makers in relation to future resource allocation.

METHODS

Using a single blinded feasibility design, 40 participants (mean age: 76.13 years, SD: 7.45, range: 65-95 years) were randomised to either (a) Club Connect, a 10-week group-based multifaceted program, comprising psychoeducation and computer-based cognitive training, or (b) a waitlist control group.

RESULTS

Implementing group-based cognitive training within a clinical setting was feasible, well tolerated and accepted by participants. Further, cognitive training, in comparison to the waiting list control, was associated with moderate to very large effect size improvements in depression, stress and inhibition (ηp2 = 0.115-0.209). We also found moderate effect size improvements on measures of daily functioning, wellbeing and cognitive flexibility. Small effect size improvements for other cognitive and psychosocial outcomes were also observed. The average cost per person participating in in the intervention was AU$607.50.

CONCLUSIONS

Our findings support the feasibility of implementing group-based cognitive training into a specialised clinical (public health) setting. This trial was registered on the Australian and New Zealand Clinical Trial Registry (ACTRN12619000195156, 12/02/2019).

The Relationship Between Scoliosis, Spinal Bone Density, and Truncal Muscle Strength in Familial Dysautonomia Patients

This combined retrospective and prospective study aimed to investigate the relationship between scoliosis, spinal bone mineral density (BMD), and truncal muscle strength in patients with familial dysautonomia (FD). A total of 79 FD patients (40 male, 39 female) aged 5-44 years were included. The severity of scoliosis, lumbar spine BMD (Z-score), and truncal muscle strength were assessed. Correlations were analyzed using Pearson's correlation coefficient. Inverse correlations were observed between scoliosis severity and BMD (r = - 0.328, p = 0.001), as indicated by increasingly negative Z-score values with worsening osteoporosis. There were also inverse correlations between scoliosis and truncal muscle strength (r = - 0.595, p < 0.001). The correlation between scoliosis and age was notable up to 22 years (r = 0.421, p = 0.01), but not in the older age group (22-44 years). Our study identified inverse correlations between osteoporosis and scoliosis, as well as between scoliosis and truncal muscle strength, in FD patients. These findings suggest that there may be a relationship between bone density, muscle strength, and the severity of spinal curvature in this population. While our results highlight the potential importance of early diagnosis and management of osteoporosis, and possibly the benefits of physical therapy to strengthen truncal muscles, further research is needed to determine the direct impact of these interventions on preventing the progression of scoliosis and its associated complications in FD patients. A long-term longitudinal study could provide more insights into these relationships and inform treatment strategies for FD patients.

Early intervention with Interleukin-1 Receptor Antagonist Protein modulates catabolic microRNA and mRNA expression in cartilage after impact injury

OBJECTIVE

The purpose of this controlled laboratory study was to determine the efficacy of Interleukin-1 Receptor Antagonist Protein (IRAP) treatment as an early intervention strategy by examining the changes in microRNA and mRNA expression in cartilage in an ex-vivo porcine knee joint impact model.

METHODS

Custom impact device was used to create replicable injury ex-vivo to intact porcine knee joint. Injury was caused by dropping a 10 kg weight one time from 1 m directly above the knee in extension. One hour after impact 20 μg/ml IRAP solution was intra-articularly injected. At 8 h post-injury, cartilage samples were harvested for cell viability and genetic expression analysis. Genetic expression of miR-27b, miR-140, miR-125b, ADAMTS-4, ADAMTS-5, MMP-3, IL-1β, and TNF-α were analyzed by RT-PCR. Cell viability image analysis was performed using ImageJ software. Groups were compared by analysis of variance (ANOVA) followed by Tukey's post-hoc test. A P-value <0.05 was considered significant.

RESULTS

At 8 h after IRAP treatment, expressions of ADAMTS-4, ADAMTS-5, MMP-3, IL-1β, and TNF-α in cartilage were significantly down-regulated from injury group (all P < 0.001). MiR-140, miR-125b, and miR-27b expressions were significantly up-regulated after treatment as compared to control and injury groups (all P < 0.001).

CONCLUSION

This study demonstrates that IRAP treatment administered during acute phase of cartilage impact injury increases expression levels of miR-140, miR-125b, and miR-27b in cartilage, indicating increased inhibition of their respective matrix-degrading enzymes. Clinically, these findings support the potential of IRAP treatment as an early intervention strategy for the prevention of cartilage degeneration after impact injury.

Psychosocial and Neurohormonal Predictors of HIV Disease Progression (CD4 Cells and Viral Load): A 4 Year Prospective Study

Most studies of psychosocial predictors of disease progression in HIV have not considered norepinephrine (NE), a neurohormone related to emotion and stress, even though NE has been related to accelerated viral replication in vitro and impaired response to antiretroviral therapy (ART). We therefore examined NE, cortisol, depression, hopelessness, coping, and life event stress as predictors of HIV progression in a diverse sample. Participants (n = 177) completed psychological assessment, blood draws [CD4, viral load (VL)], and a 15 h urine sample (NE, cortisol) every 6 months over 4 years. Hierarchical linear modeling (HLM) was used to model slope in CD4 and VL controlling for ART at every time point, gender, age, race, SES, and initial disease status. NE (as well as depression, hopelessness, and avoidant coping) significantly predicted a greater rate of decrease in CD4 and increase in VL. Cortisol was not significantly related to CD4, but predicted VL increase. To our knowledge, this is the first study relating NE, in vivo, to accelerated disease progression over an extended time. It also extends our previous 2 year study by relating depressed mood and coping to accelerated disease progression over 4 years.

Focusing in multiwell potentials: applications to ion channels

We investigate nonequilibrium stationary distributions induced by stochastic dichotomous noise in double-well and multiwell models of ion channel gating kinetics. The channel kinetics is analyzed using both overdamped Langevin equations and master equations. With the Langevin equation approach we show a nontrivial focusing effect due to the external stochastic noise, namely, the concentration of the probability distribution in one of the two wells of a double-well system or in one or more of the wells of the multiwell model. In the multiwell system, focusing in the outer wells is shown to be achievable under physiological conditions, while focusing in the central wells has proved possible so far only at very low temperatures. We also discuss the strength of the focusing effect and obtain the conditions necessary for maximal focusing to appear. These conditions cannot be predicted by a simple master equation approach.

Could the mechanisms of bariatric surgery hold the key for novel therapies? report from a Pennington Scientific Symposium

Bariatric surgery is the most effective method for promoting dramatic and durable weight loss in morbidly obese subjects. Furthermore, type 2 diabetes is resolved in over 80% of patients. The mechanisms behind the amelioration in metabolic abnormalities are largely unknown but may be due to changes in energy metabolism, gut peptides and food preference. The goal of this meeting was to review the latest research to better understand the mechanisms behind the 'magic' of bariatric surgery. Replication of these effects in a non-surgical manner remains one of the ultimate challenges for the treatment of obesity and diabetes. Promising data on energy metabolism, gastrointestinal physiology, hedonic response and food intake were reviewed and discussed.

Freak waves in the linear regime: a microwave study

Microwave transport experiments have been performed in a quasi-two-dimensional resonator with randomly distributed conical scatterers. At high frequencies, the flow shows branching structures similar to those observed in stationary imaging of electron flow. Semiclassical simulations confirm that caustics in the ray dynamics are responsible for these structures. At lower frequencies, large deviations from Rayleigh's law for the wave height distribution are observed, which can only partially be described by existing multiple-scattering theories. In particular, there are "hot spots" with intensities far beyond those expected in a random wave field. The results are analogous to flow patterns observed in the ocean in the presence of spatially varying currents or depth variations in the sea floor, where branches and hot spots lead to an enhanced frequency of freak or rogue wave formation.

Impact of intensive stem cell mobilization therapy on outcomes following autologous stem cell transplantation (ASCT) for non- Hodgkin lymphoma (NHL)

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Background: We retrospectively evaluated the impact of intense [I] stem cell mobilization therapy on event-free survival [EFS] and overall survival [OS] following ASCT for NHL. Methods: 80 patients (pt) were studied (2 Burkitt, 3 primary CNS, 3 follicular, 2 intravascular, 43 large cell, 12 mantle cell, 9 transformed, and 6 peripheral T-cell). Patients with very-high risk features (LDH > 500 IU/L, first remissions < 1 year, 2 or more extra-nodal sites, and/or primary CNS/intravascular/mantle cell/peripheral T-cell histology) were prospectively allocated to I stem cell mobilization (requiring hospitalization) with either cyclophosphamide [C] (6 g/m2) + etoposide [E] (2g/m2) + filgrastim [G-CSF] (±rituximab [R]) (n=5) or with cytarabine [A] (2 g/m2 bid for 8 doses) + E (40 mg/kg) + G- CSF (±R) (n=45). 30 pt were mobilized (outpatient) with C 4g/m2 + G-CSF ±R (non-intense [NI] mobilization). 76 pt received ASCT conditioning with carmustine [B] + E and C (CBV) and 2 with B + E + A and melphalan (BEAM); 2 pt did not undergo ASCT. Results: The median age was 54 (21–69 years [yr]) and 57% had an elevated LDH at presentation. 39 pt (49%) were primary induction failures (PIF). At NHL presentation, 38% were IPI high-intermediate or high risk. There were 3 non-relapse mortalities (4%): (2) B pneumonitis and (1) multi-organ failure (all following ASCT). With a median follow-up of 1.8 yr (0.1–6.4), the overall median EFS is 3 yr (48% [34–62] at 4 yr) and the median OS is 4.7 yr (59% [43–72] at 4 yr). Patients receiving I mobilization were similar to those receiving NI mobilization in terms of the # of prior therapies (median 2, each), the presenting IPI risk score, and the percent PIF (57% vs 41%; p=0.17). There were trends favoring I mobilization for both 4 yr EFS (58% [41–75] vs 35% [13–57]) and OS (66% [48–84] vs 52% [32–72]), neither statistically significant. In the sub-group of large B-cell NHL, 4 yr EFS was the same in pt receiving I mobilization (81% [63–98] vs 73% [50–96]; p=0.33) but OS was better (91% [79–100] vs 58% [35–82]; p=0.02). Conclusions: I stem cell mobilization therapy, compared to NI mobilization therapy, may improve outcomes for NHL pt with very-high risk features and may overcome the anticipated poor prognosis of these pt.

No significant financial relationships to disclose.

Driving abilities in frontotemporal dementia patients

OBJECTIVE

To evaluate driving competency and the relationship between neuropsychiatric symptoms and driving behavior in frontotemporal dementia (FTD) patients.

METHODS

Fifteen patients with a diagnosis of FTD and 15 healthy controls were administered a driving simulation task. Measures of driving performance and neuropsychiatric symptoms were assessed.

RESULTS

The FTD patients received more speeding tickets, ran more stop signs and were involved in more off-road crashes and collisions than the controls. The patients' overall average speed was significantly higher. Driving performance was correlated with agitated behavior.

CONCLUSIONS

Behavioral changes characteristic of FTD patients have an impact on their driving skills leading to inappropriate driving behavior.

Falsely raised TSH levels due to human anti-mouse antibody interfering with thyrotropin assay

The case of a 39-year-old woman who was referred for weight gain and amenorrhoea is reported. Laboratory evaluation showed high levels of thyroid-stimulating hormone (TSH). The patient was started on increasing doses of levothyroxine for subclinical hypothyroidism. TSH remained persistently raised and the patient became thyrotoxic. Evaluation at another laboratory showed normal levels of TSH, raising the possibility of interfering substances. TSH levels were normalised with the addition of mouse serum to the patient's sample, confirming the presence of human anti-mouse antibodies as the interfering substance in the TSH assay.

Genetic linkage of a novel autosomal dominant restrictive cardiomyopathy locus

BACKGROUND

In recent years, non-syndromic idiopathic cardiomyopathies have increasingly been characterised as autosomal dominant conditions caused by single gene mutations. Loci have been identified for hypertrophic and dilated cardiomyopathy, and in some cases the same loci are associated with restrictive cardiomyopathy (RCM). In a kindred with RCM that we previously reported, we ruled out the known cardiomyopathy loci and other candidate genes by linkage analysis and mutation screening.

METHODS AND RESULTS

Here we report a genome-wide analysis in this family that has resulted in linkage to a region on chromosome 10.

CONCLUSIONS

There are no genes in the interval that are known to cause idiopathic cardiomyopathy, and thus this linkage represents localisation of a new RCM locus.

Melanocortin-1 receptor gene variants affect pain and mu-opioid analgesia in mice and humans

BACKGROUND

A recent genetic study in mice and humans revealed the modulatory effect of MC1R (melanocortin-1 receptor) gene variants on kappa-opioid receptor mediated analgesia. It is unclear whether this gene affects basal pain sensitivity or the efficacy of analgesics acting at the more clinically relevant mu-opioid receptor.

OBJECTIVE

To characterise sensitivity to pain and mu-opioid analgesia in mice and humans with non-functional melanocortin-1 receptors.

METHODS

Comparisons of spontaneous mutant C57BL/6-Mc1r(e/e) mice to C57BL/6 wildtype mice, followed by a gene dosage study of pain and morphine-6-glucuronide (M6G) analgesia in humans with MC1R variants.

RESULTS

C57BL/6-Mc1r(e/e) mutant mice and human redheads--both with non-functional MC1Rs--display reduced sensitivity to noxious stimuli and increased analgesic responsiveness to the mu-opioid selective morphine metabolite, M6G. In both species the differential analgesia is likely due to pharmacodynamic factors, as plasma levels of M6G are similar across genotype.

CONCLUSIONS

Genotype at MC1R similarly affects pain sensitivity and M6G analgesia in mice and humans. These findings confirm the utility of cross species translational strategies in pharmacogenetics.

[Quality of data transfer in perinatal data -- experience of a centre]

BACKGROUND

A sufficient quality of data transfer from written patient records to electronic data processing is a precondition for a reasonable usage of perinatal data. However the quality of data transfer of the almost 200 characteristics routinely recorded at each delivery is largely unknown.

MATERIALS AND METHODS

The quality of data transfer of 33 characteristics in 350 randomly selected singleton deliveries of the women's clinic of the University of Marburg from 2002 and 2003 has been checked by comparing electronically recorded data with the original written documents.

RESULTS

The quality of data transfer of the tested characteristics turned out to be heterogeneous. Characteristics necessary to calculate quality indicators show a very high data quality when excluding the characteristic attendance of a paediatrician. The quality of data transfer of characteristics denoting time as well as blood gas analysis are heterogeneous. Characteristics with a low quality of data transfer are associated with ambiguous instructions, the fact that the coding obstetrician is not dealing in the first instance with the item being encoded and the characteristics are of no immediate relevance for delivery, as well as difficult application of the software.

CONCLUSION

The quality of data transfer of the characteristics collected in perinatal surveys needs to be validated. The type and amount of data being collected should be reassessed considering improvements of data quality.

Scar intensity statistics in the position representation

We obtain general predictions for the distribution of wave function intensities in position space on the periodic orbits of chaotic ballistic systems. The expressions depend on effective system size , instability exponent of the periodic orbit, and proximity to a focal point of the orbit. Limiting expressions are obtained that include the asymptotic probability distribution of rare high-intensity events and a perturbative formula valid in the limit of weak scarring. For finite system sizes, a single scaling lambdaN variable describes deviations from the semiclassical N--> infinity limit.

Brownian motion model of quantization ambiguity and universality in chaotic systems

We examine spectral equilibration of quantum chaotic spectra to universal statistics in the context of the Brownian motion model. Two competing time scales, proportional and inversely proportional to the classical relaxation time, jointly govern the equilibration process. Multiplicity of quantum systems having the same semiclassical limit is not sufficient to obtain equilibration of any spectral modes in two-dimensional systems, while in three-dimensional systems equilibration for some spectral modes is possible if the classical relaxation rate is slow. Connections are made with upper bounds on semiclassical accuracy and with fidelity decay in the presence of a weak perturbation.

Correlation function bootstrapping in quantum chaotic systems

We discuss a general and efficient approach for "bootstrapping" short-time correlation data in chaotic or complex quantum systems to obtain information about long-time dynamics and stationary properties, such as the local density of states. When the short-time data are sufficient to identify an individual quantum system, we obtain a systematic approximation for the spectrum and wave functions. Otherwise, we obtain statistical properties, including wave function intensity distributions, for an ensemble of all quantum systems sharing the given short-time correlations. The results are valid for open or closed systems, and are stable under perturbation of the short-time input data. Numerical examples include quantum maps and two-dimensional anharmonic oscillators.

Semiclassical accuracy in phase space for regular and chaotic dynamics

A phase-space semiclassical approximation valid to O(h) at short times is used to compare semiclassical accuracy for long-time and stationary observables in chaotic, stable, and mixed systems. Given the same level of semiclassical accuracy for the short time behavior, the squared semiclassical error in the chaotic system grows linearly in time, in contrast with quadratic growth in the classically stable system. In the chaotic system, the relative squared error at the Heisenberg time scales linearly with h(eff), allowing for unambiguous semiclassical determination of the eigenvalues and wave functions in the high-energy limit, while in the stable case the eigenvalue error always remains of the order of a mean level spacing. For a mixed classical phase space, eigenvalues associated with the chaotic sea can be semiclassically computed with greater accuracy than the ones associated with stable islands.

Eigenstate structure in graphs and disordered lattices

We study wave function structure for quantum graphs in the chaotic and disordered regime, using measures such as the wave function intensity distribution and the inverse participation ratio. The result is much less ergodicity than expected from random matrix theory, even though the spectral statistics are in agreement with random matrix predictions. Instead, analytical calculations based on short-time semiclassical behavior correctly describe the eigenstate structure.

Scarring effects on tunneling in chaotic double-well potentials

The connection between scarring and tunneling in chaotic double-well potentials is studied in detail through the distribution of level splittings. The mean level splitting is found to have oscillations as a function of energy, as expected if scarring plays a role in determining the size of the splittings, and the spacing between peaks is observed to be periodic of period 2 pi Planck's over 2 pi in action. Moreover, the size of the oscillations is directly correlated with the strength of scarring. These results are interpreted within the theoretical framework of Creagh and Whelan. The semiclassical limit and finite-Planck's over 2 pi effects are discussed, and connections are made with reaction rates and resonance widths in metastable wells.

Localization of eigenfunctions in the stadium billiard

We present a systematic survey of scarring and symmetry effects in the stadium billiard. The localization of individual eigenfunctions in Husimi phase space is studied first, and it is demonstrated that on average there is more localization than can be accounted for by random-matrix theory, even after removal of bouncing-ball states and visible scars. A major point of the paper is that symmetry considerations, including parity and time-reversal symmetries, enter to influence the total amount of localization. The properties of the local density of states are also investigated, as a function of phase space location. Aside from the bouncing-ball region of phase space, excess localization is found on short periodic orbits and along certain symmetry-related lines; the origin of all these sources of localization is discussed quantitatively and comparison is made with analytical predictions. Scarring is observed to be present in all the energy ranges considered. In light of our results, the excess localization in individual eigenstates is interpreted as being primarily due to symmetry effects.

Disability as a function of social networks and support in elderly African Americans and Whites: the Duke EPESE 1986--1992

OBJECTIVES

We examined the association of structural and functional aspects of social relationships with change in disability, and the degree to which race modifies these associations.

METHODS

Data are from a population-based sample of 4,136 African Americans and Whites aged > or = 65 living in North CAROLINA: Disability data were collected during seven consecutive yearly interviews and summarized in two outcome measures. Measures of social relationships included five measures representing network size, extent of social interaction, and specific type of relationships, as well as instrumental and emotional support. Weighted proportional odds models were fitted to model disability as a function of baseline social network and support variables, and the interaction of each variable with follow-up time.

RESULTS

Network size and social interaction showed significant negative associations with disability risks, which did not vary by race, or as a function of time. Social interaction with friends was associated with a reduced risk for disability, but social interaction with children or relatives was not related to disability. Instrumental support was associated with a significantly increased disability risk, with a greater adverse effect among Whites than African AMERICANS: Emotional support was not associated with disability, but a protective effect for ADL disability was found after controlling for its intercorrelation with instrumental support.

DISCUSSION

The findings provide further evidence for the role of social relationships in the disablement process, although not all types of social relationships may be equally beneficial. Furthermore, these associations may be more complex than simple causal effects. There were few racial differences in the association of social relationships with disability, with the possible exception of instrumental support, which may allude to possible sociocultural differences in the experience of instrumental support exchanges.

Chemotherapy for human immunodeficiency virus-associated non-Hodgkin's lymphoma in combination with highly active antiretroviral therapy

PURPOSE

This study investigated the efficacy, toxicity, and pharmacokinetic interactions resulting from simultaneous combination chemotherapy and highly active antiretroviral therapy (HAART) for patients with human immunodeficiency virus (HIV)-associated non-Hodgkin's lymphoma (NHL). In addition, the effects on viral load, CD4 counts, and opportunistic infections were examined with the use of combination chemotherapy combined with HAART.

PATIENTS AND METHODS

Sixty-five patients with previously untreated and measurable disease at any stage of HIV-associated NHL of intermediate or high grade were entered onto this study at 17 different centers. The first 40 patients entered onto the study received reduced doses of cyclophosphamide and doxorubicin, combined with vincristine and prednisone (modified CHOP [mCHOP]), whereas the subsequent 25 patients entered onto the study received full doses of CHOP combined with granulocyte colony-stimulating factor (G-CSF). All patients also received stavudine, lamivudine, and indinavir.

RESULTS

The complete response rates were 30% and 48% among patients who received mCHOP and full-dose CHOP combined with HAART, respectively. Grade 3 or 4 neutropenia occurred in 25% of patients receiving mCHOP and 12% of those receiving full-dose CHOP combined with G-CSF (25% v 12%). There were similar numbers of patients with grade 3 or 4 hyperbilirubinemia (12% and 17%), constipation and abdominal pain (18% and 17%), and transaminase elevation (48% and 52%) on the modified and full-dose arms of the study, respectively. Doxorubicin clearance and indinavir concentration curves were similar among patients on this study and historical controls, whereas cyclophosphamide clearance was 1.5-fold reduced as compared with control values. Human immunodeficiency virus (HIV) load declined from a median baseline value of 29,000 copies/mL to a median minimum value on therapy of 500 copies/mL.

CONCLUSION

Either modified-dose or full-dose CHOP chemotherapy for HIV-NHL, delivered with HAART, is effective and tolerable.

Periodic orbit effects on conductance peak heights in a chaotic quantum dot

We study the effects of short-time classical dynamics on the distribution of Coulomb blockade peak heights in a chaotic quantum dot. The location of one or both leads relative to the short unstable orbits, as well as relative to the symmetry lines, can have large effects on the moments and on the head and tail of the conductance distribution. We study these effects analytically as a function of the stability exponent of the orbits involved, and also numerically using the stadium billiard as a model. The predicted behavior is robust, depending only on the short-time behavior of the many-body quantum system, and consequently insensitive to moderate-sized perturbations and interactions.

Differential leptin responses to acute and chronic biliary obstruction in rats

BACKGROUND/AIMS

Recently leptin, a protein released from adipocytes, has been identified as a potent circulating satiety factor. We therefore undertook this series of experiments to examine leptin's role in the anorexia associated with biliary obstruction.

METHODS

Rats underwent either surgical bile duct resection (BDR) or sham resection (sham). Body weight, and food and water intake were measured during a baseline period and for 8 days after surgery. At 4, 8 and 16 h as well as on days 2, 4, 6, and 8 postsurgery, sham and BDR rats were sacrificed and sera collected for subsequent measurement of leptin hormone concentration by RIA. White adipose tissue was collected on days 2, 4, 6 and 8 for leptin mRNA determination by Northern blot.

RESULTS

Obstructive cholestasis in BDR rats caused significant anorexia for up to 7 days post-surgery, whereas in sham rats, a significant decrease in food intake was only observed in the first 24-h period following surgery. In both sham and BDR rats, water intake was significantly decreased during the first 24-h period after surgery, but had recovered to baseline levels by day 2 in both groups. Fat pad mass corrected to body weight was not significantly different between the two experimental groups. Serum leptin levels were significantly increased 4 and 8 h after surgery, had normalized by 16 h post-surgery, and were then decreased in BDR rats on days 2, 4, 6 and 8 compared with controls. Leptin mRNA levels in epididymal fat pads were decreased by approximately 2-fold in BDR rats compared with sham rats on days 2, 4, 6 and 8. Furthermore, day 5 BDR and sham rats demonstrated similar anorectic responses to centrally administered leptin.

CONCLUSIONS

Leptin production is significantly increased early after biliary obstruction but is reduced after prolonged biliary obstruction. Increased circulating leptin levels may contribute to the profound anorexia observed early after biliary obstruction but appear not to mediate the anorexia observed during more chronic biliary obstruction.

Short-time effects on eigenstate structure in sinai billiards and related systems

There is much latitude between the requirements of Schnirelman's theorem regarding the ergodicity of individual high-energy eigenstates of classically chaotic systems on the one hand, and the extreme requirements of random matrix theory on the other. It seems likely that some eigenstate statistics and long-time transport behavior bear nonrandom imprints of the underlying classical dynamics while simultaneously obeying Schnirelman's theorem. Indeed this was shown earlier in the case of systems that approach classical ergodicity slowly, and is also realized in the scarring of eigenstates, even in the Planck's over 2pi-->0 limit, along unstable periodic orbits and their manifolds. Here we demonstrate the nonrandom character of eigenstates of Sinai-like systems. We show that mixing between channels in Sinai systems is dramatically deficient compared to random matrix theory predictions. The deficit increases as |ln Planck's over 2pi| for Planck's over 2pi-->0, and is due to the vicinity of the measure zero set of orbits that never collide with the Sinai obstruction. Coarse graining to macroscopic scales recovers the Schnirelman result. Three systems are investigated here: a Sinai-type billiard, a quantum map that possesses the essential properties of the Sinai billiard, and a unitary map corresponding to a quasirandom Hamiltonian. Various wave function and long-time transport statistics are defined, theoretically investigated, and compared to numerical data.