Autism spectrum disorder, extremism and risk assessment

BACKGROUND

To date, there is no evidence supporting the existence of an association between Autism Spectrum Disorder (ASD) and extremism in the general population. However, there is increasing recognition that several features of ASD may provide the context of vulnerability to engage in extremist behaviour.

AIMS

This paper sets out the case for a dedicated clinical approach to better integrate clinical risk appraisal processes with an assessment of ASD individuals' vulnerabilities within the Criminal Justice System.

METHODS AND RESULTS

In this paper the Framework for the Assessment of Risk & Protection in Offenders on the Autistic Spectrum (FARAS): A Guide for Risk Assessors Working with Offenders on the Autistic Spectrum is explored. In developing the FARAS, Al-Attar proposed seven facets of ASD that 'may have different functional links with push and pull factors to terrorism' (p. 928), which include circumscribed interests; rich vivid fantasy and impaired social imagination; need for order, rules, rituals, routine and predictability; obsessionality, repetition and collecting; social interaction and communication difficulties; cognitive styles and Sensory processing.

DISCUSSION AND CONCLUSION

We describe the FARAS within the context of the most widely used clinical risk appraisal 'aide memoire' instruments integral to the Structured Professional Judgement of risk process, namely the HCR20v3.

Understanding the Use of the Term "Weaponized Autism" in An Alt-Right Social Media Platform

BACKGROUND

The term "weaponized autism" is frequently used on extremist platforms. To better understand this, we conducted a discourse analysis of posts on Gab, an alt-right social media platform.

METHODS

We analyzed 711 posts spanning 2018-2019 and filtered for variations on the term "weaponized autism".

RESULTS

This term is used mainly by non-autistic Gab users. It refers to exploitation of perceived talents and vulnerabilities of "Weaponized autists", described as all-powerful masters-of-technology who are devoid of social skills.

CONCLUSIONS

The term "weaponized autism" is simultaneously glorified and derogatory. For some autistic people, the partial acceptance offered within this community may be preferable to lack of acceptance offered in society, which speaks to improving societal acceptance as a prevention effort.

ECHO autism adult healthcare: Training community clinicians to provide quality care for autistic adults

Autistic adults experience significant unmet healthcare needs, with opportunities for improvement in both the systems and the practitioners who serve this population. Primary care physicians/practitioners (PCPs) are a natural choice to provide comprehensive care to autistic adults but often lack experience in serving this population. This pilot study developed and tested an Extension for Community Healthcare Outcomes (ECHO) Autism model adapted from our previous work, focused specifically on training PCPs in best-practice care for autistic adults. The project was informed directly by the perspectives and preferences of autistic adults, caregivers, and PCPs. Two consecutive cohorts of PCPs participated in ECHO Autism Adult Healthcare sessions. Each cohort met 1 h twice a month for 6 months, with 37 PCPs (n = 20 in Cohort 1, and n = 17 in Cohort 2) participating. Based on findings from the first cohort, adjustments were made to refine the session preparation, curriculum, conduct of the ECHO, resources, and evaluation. After participation in the ECHO Autism program, PCP self-efficacy and satisfaction improved, while the number of perceived barriers did not change. Knowledge did not improve significantly in Cohort 1, but after adjustments to the training model, participants in Cohort 2 showed significant knowledge gains. While attention to systems of care is critical to addressing barriers in healthcare in the autistic population, the ECHO Autism Adult Healthcare model is feasible and holds promise for improving PCP satisfaction and self-efficacy in working with autistic adults.

Vulnerability to Ideologically-Motivated Violence Among Individuals With Autism Spectrum Disorder

People with autism spectrum disorder (ASD) are represented among those who espouse extremist thought and have committed violent acts associated with their beliefs. Media often highlight a perpetrator's psychiatric diagnosis following acts of mass violence, which in some instances has included ASD. ASD may itself not provide useful information for understanding motivations. Instead, understanding specific traits and neuropsychological and other vulnerabilities may offer an opportunity to make sense of these very complex events.

The Need for a Structured Approach to Violence Risk Assessment in Autism

The relationship between autism spectrum disorder (ASD) and violence is poorly understood. Several violence risk factors are either modified by or are unique to ASD; clinicians conducting violence risk assessment of people with ASD must consider these factors. An ASD-specific risk assessment tool is clearly needed. In the absence of this, clinicians often use risk assessment tools designed for other populations, highlighting the importance of establishing their predictive validity in people with ASD. Girardi and colleagues have taken a very important step in this process in their paper, "Assessing the Risk of Inpatient Violence in Autism Spectrum Disorder," by examining whether the Historical Clinical Risk Management-20, Version 3, can predict violence in male patients with ASD in a forensic setting. Further research is needed to design a risk assessment tool specific to ASD and its unique features.

Preoperative platelet transfusions to reverse antiplatelet therapy for urgent non-cardiac surgery: an observational cohort study

Essentials An increasing number of patients requiring surgery receive antiplatelet therapy (APT). We analyzed 181 patients receiving presurgery platelet transfusions to reverse APT. No coronary thrombosis occurred after platelet transfusion. This justifies a prospective trial to test preoperative platelet transfusions to reverse APT.

SUMMARY

Background Patients receiving antiplatelet therapy (APT) have an increased risk of perioperative bleeding and cardiac adverse events (CAE). Preoperative platelet transfusions may reduce the bleeding risk but may also increase the risk of CAE, particularly coronary thrombosis in patients after recent stent implantation. Objectives To analyze the incidence of perioperative CAE and bleeding in patients undergoing non-cardiac surgery using a standardized management of transfusing two platelet concentrates preoperatively and restart of APT within 24-72 h after surgery. Methods A cohort of consecutive patients on APT treated with two platelet concentrates before non-cardiac surgery between January 2012 and December 2014 was retrospectively identified. Patients were stratified by the risk of major adverse cardiac and cerebrovascular events (MACCE). The primary objective was the incidence of CAE (myocardial infarction, acute heart failure and cardiac troponine T increase). Secondary objectives were incidences of other thromboembolic events, bleedings, transfusions and mortality. Results Among 181 patients, 88 received aspirin, 21 clopidogrel and 72 dual APT. MACCE risk was high in 63, moderate in 103 and low in 15 patients; 67 had cardiac stents. Ten patients (5.5%; 95% CI, 3.0-9.9%) developed a CAE (three myocardial infarctions, four cardiac failures and three troponin T increases). None was caused by coronary thrombosis. Surgery-related bleeding occurred in 22 patients (12.2%; 95% CI, 8.2-17.7%), making 12 re-interventions necessary (6.6%; 95% CI, 3.8-11.2%). Conclusion Preoperative platelet transfusions and early restart of APT allowed urgent surgery and did not cause coronary thromboses, but non-thrombotic CAEs and re-bleeding occurred. Randomized trials are warranted to test platelet transfusion against other management strategies.

Neurogenetic analysis of childhood disintegrative disorder

BACKGROUND

Childhood disintegrative disorder (CDD) is a rare form of autism spectrum disorder (ASD) of unknown etiology. It is characterized by late-onset regression leading to significant intellectual disability (ID) and severe autism. Although there are phenotypic differences between CDD and other forms of ASD, it is unclear if there are neurobiological differences.

METHODS

We pursued a multidisciplinary study of CDD (n = 17) and three comparison groups: low-functioning ASD (n = 12), high-functioning ASD (n = 50), and typically developing (n = 26) individuals. We performed whole-exome sequencing (WES), copy number variant (CNV), and gene expression analyses of CDD and, on subsets of each cohort, non-sedated functional magnetic resonance imaging (fMRI) while viewing socioemotional (faces) and non-socioemotional (houses) stimuli and eye tracking while viewing emotional faces.

RESULTS

We observed potential differences between CDD and other forms of ASD. WES and CNV analyses identified one or more rare de novo, homozygous, and/or hemizygous (mother-to-son transmission on chrX) variants for most probands that were not shared by unaffected sibling controls. There were no clearly deleterious variants or highly recurrent candidate genes. Candidate genes that were found to be most conserved at variant position and most intolerant of variation, such as TRRAP, ZNF236, and KIAA2018, play a role or may be involved in transcription. Using the human BrainSpan transcriptome dataset, CDD candidate genes were found to be more highly expressed in non-neocortical regions than neocortical regions. This expression profile was similar to that of an independent cohort of ASD probands with regression. The non-neocortical regions overlapped with those identified by fMRI as abnormally hyperactive in response to viewing faces, such as the thalamus, cerebellum, caudate, and hippocampus. Eye-tracking analysis showed that, among individuals with ASD, subjects with CDD focused on eyes the most when shown pictures of faces.

CONCLUSIONS

Given that cohort sizes were limited by the rarity of CDD, and the challenges of conducting non-sedated fMRI and eye tracking in subjects with ASD and significant ID, this is an exploratory study designed to investigate the neurobiological features of CDD. In addition to reporting the first multimodal analysis of CDD, a combination of fMRI and eye-tracking analyses are being presented for the first time for low-functioning individuals with ASD. Our results suggest differences between CDD and other forms of ASD on the neurobiological as well as clinical level.

Nonequilibrium random matrix theory: Transition probabilities

In this paper we present an analytic method for calculating the transition probability between two random Gaussian matrices with given eigenvalue spectra in the context of Dyson Brownian motion. We show that in the Coulomb gas language, in large N limit, memory of the initial state is preserved in the form of a universal linear potential acting on the eigenvalues. We compute the likelihood of any given transition as a function of time, showing that as memory of the initial state is lost, transition probabilities converge to those of the static ensemble.

Trauma and Violence in Autism

Comorbidities of autism spectrum disorder are discussed as an introduction to the argument that, although ASD may modify presentation, it does not confer any protection against other disorder, including the negative effects of trauma (e.g., posttraumatic stress disorder). Dr. Im's hypotheses are discussed, and a case example of childhood disintegrative disorder (CDD) is raised to give clinical support to his hypotheses. CDD is a rare form of ASD that is defined by late onset, a traumatic prodrome, onset of behaviors including some with similarities to PTSD, and aggression.

Tolerance of platelet concentrates treated with UVC-light only for pathogen reduction--a phase I clinical trial

BACKGROUND

The THERAFLEX UV-Platelets pathogen reduction system for platelet concentrates (PCs) operates with ultraviolet C light (UVC; 254 nm) only without addition of photosensitizers. This phase I study evaluated safety and tolerability of autologous UVC-irradiated PCs in healthy volunteers.

METHODS

Eleven volunteers underwent two single (series 1 and 2) and one double apheresis (series 3). PCs were treated with UVC, stored for 48 h and retransfused in a dose-escalation scheme: 12·5, 25% and 50% of a PC (series 1); one complete PC (series 2); two PCs (series 3). Platelet counts, fibrinogen, activated partial thromboplastin time, prothrombin time, D-dimer, standard haematology, temperature, heart rate, blood pressure and clinical chemistry parameters were measured. One- and 24-h corrected count increments were determined in series 2 and 3. Platelet-specific antibodies were assessed before and at the end of the study.

RESULTS

Neither adverse reactions related to transfusions nor antibodies against UVC-treated platelets were observed. Corrected count increments did not differ between series 2 and 3.

CONCLUSIONS

Repeated transfusions of autologous UVC-treated PCs were well tolerated and did not induce antibody responses in all volunteers studied. EudraCT No. 2010-023404-26.

Hierarchical axion inflation

We propose a new field theory mechanism for generating an effective trans-Planckian decay constant from sub-Planckian ones. Using the minimal two axions and a hierarchy between two axion decay constants is sufficient for realizing inflation through nonperturbative effects only and with minimal tuning. The inflationary motion is kept entirely within a sub-Planckian domain. We outline possible strategies of embedding the model in a string theory setup.

Crime and psychiatric disorders among youth in the US population: an analysis of the National Comorbidity Survey-Adolescent Supplement

OBJECTIVE

Current knowledge regarding psychiatric disorders and crime in youth is limited to juvenile justice and community samples. This study examined relationships between psychiatric disorders and self-reported crime involvement in a sample of youth representative of the US population.

METHOD

The National Comorbidity Survey-Adolescent Supplement (N = 10,123; ages 13-17 years; 2001-2004) was used to examine the relationship between lifetime DSM-IV-based diagnoses, reported crime (property, violent, other), and arrest history. Logistic regression compared the odds of reported crime involvement with specific psychiatric disorders to those without any diagnoses, and examined the odds of crime by psychiatric comorbidity.

RESULTS

Prevalence of crime was 18.4%. Youth with lifetime psychiatric disorders, compared to no disorders, had significantly greater odds of crime, including violent crime. For violent crime resulting in arrest, conduct disorder (CD) (odds ratio OR = 57.5; 95% CI = 30.4, 108.8), alcohol use disorders (OR = 19.5; 95% CI = 8.8, 43.2), and drug use disorders (OR = 16.1; 95% CI = 9.3, 27.7) had the greatest odds with similar findings for violent crime with no arrest. Psychiatric comorbidity increased the odds of crime. Youth with 3 or more diagnoses (16.0% of population) accounted for 54.1% of those reporting arrest for violent crime. Youth with at least 1 diagnosis committed 85.8% of crime, which was reduced to 67.9% by removing individuals with CD. Importantly, 88.2% of youth with mental illness reported never having committed any crime.

CONCLUSION

Our findings highlight the importance of improving access to mental health services for youthful offenders in community settings, given the substantial associations found between mental illness and crime in this nationally representative epidemiological sample.

Relationship between body condition score and ultrasound measurement of backfat thickness in multiparous Holstein dairy cows at different production phases

BACKGROUND

The validity of the body condition score (BCS) for evaluating subcutaneous fat has been questioned because of its subjectivity. With the advent of ultrasonography, backfat thickness (BFT) can be objectively measured and used to assess the energy status of dairy cows in conjunction with BCS.

OBJECTIVE

Determine the relationship between BCS and ultrasound measurements of BFT throughout the lactation cycle.

METHODS

Cows (n = 1123) were selected randomly and classified according to their lactation stage into four different groups. BCS was determined using a 5-point scale and BFT measurements were obtained using a 5-MHz linear transducer.

RESULTS

The correlation coefficient (r) for the relationship between BCS and BFT varied according to the stage of lactation. There was a high correlation (r = 0.96-0.98) and relationship (r(2) = 0.92-0.96) between BCS and BFT. The highest correlation was found at BFT values of 10-35 mm and BCS of 2-4.5 units.

CONCLUSION

BCS is a practical tool for evaluating body condition; furthermore, it may be as valid as BFT for the estimation of subcutaneous fat in Holstein dairy cows over time.

Selective serotonin reuptake inhibitors and tricyclic antidepressants in the acute treatment of chronic depression and dysthymia: a systematic review and meta-analysis

INTRODUCTION

Chronic depression represents a substantial portion of depressive disorders and is associated with severe consequences. This review examined the efficacy and acceptability of selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs) in the treatment of chronic depression. Additionally, the comparative effectiveness of the two types of antidepressants has been examined.

METHODS

A systematic search was conducted in the following databases: CENTRAL, MEDLINE, EMBASE, ISI Web of Science, BIOSIS, PsycINFO, and CINAHL. Primary efficacy outcome was a response to treatment; primary acceptance outcome was dropping out of the study. Only randomized controlled trials were considered.

RESULTS

We identified 20 studies with 22 relevant comparisons. 19 studies focused on samples with a majority of dysthymic patients. Both SSRIs and TCAs are efficacious in terms of response rates when compared to placebo (Benefit Ratio [BR]=1.49; p<0.001 for SSRIs and BR=1.74; p<0.001 for TCAs) and no statistically significant differences between the active drugs and placebo in terms of dropout rates could be found. No differences in effectiveness were found between SSRIs and TCAs in terms of response rates (BR=1.01; p=0.91), yet, SSRIs showed statistically better acceptability in terms of dropout rates than TCAs (Odds Ratio [OR]=0.41; p=0.02).

LIMITATIONS

The methodological quality of the primary studies was evaluated as unclear in many cases and more evidence is needed to assess the efficacy of SSRIs and TCAs in patients suffering from chronic forms of depression other than dysthymia.

CONCLUSIONS

This systematic review provides evidence for the efficacy of both SSRIs and TCAs in the treatment of chronic depression and showed a better acceptability of SSRIs.

Healthcare issues for children on the autism spectrum

PURPOSE OF REVIEW

We provide a summary of issues relevant to healthcare and health delivery in autism and related disorders, with a focus on work published in the past 5 years.

RECENT FINDINGS

Autism has a strong genetic basis as evidenced by the high recurrence rate in families and its associations with Fragile X syndrome and tuberous sclerosis. Early diagnosis of autism is important, given the potential for improvement with intervention. Although its associations have been reported with events such as measles-mumps-rubella immunization, large-scale studies have not supported such links. Controlled drug trials have increased in frequency and drug treatment may be helpful in addressing frequently associated behavioural and emotional difficulties. Alternative treatments are frequently preferred by parents.

SUMMARY

Knowledge of autism among healthcare professionals has increased but gaps remain. Physicians and other professionals can facilitate the delivery of healthcare services to individuals with autism. Awareness of empirically validated treatments will facilitate work with individuals with autism and related disorders as well as with their families.

A Method for Field Infestation with Meloidogyne incognita

A field inoculation method was developed to produce Meloidogyne spp. infestation sites with minimal quantities of nematode inoculum and with a reduced labor requirement compared to previous techniques. In a preseason-methyl bromidefumigated site, nematode egg suspensions were delivered at concentrations of 0 or 10(x) eggs/m of row where x = 2.12, 2.82, 3.52, or 4.22 through a drip line attached to the seed firmer of a commercial 2-row planter into the open seed furrow while planting cowpea. These treatments were compared to a hand-inoculated treatment, in which 10(3.1) eggs were delivered every 30 cm in 5 ml of water agar suspension 2 weeks after planting. Ten weeks after planting, infection of cowpea roots was measured by gall rating and gall counts on cowpea roots. A linear relationship between the inoculation levels and nematode-induced galls was found. At this time, the amount of galling per root system in the hand-inoculated treatment was less than in the machine-applied treatments. Advantages of this new technique include application uniformity and low population level requisite for establishing the nematode. This method has potential in field-testing of Meloidogyne spp. management strategies by providing uniform infestation of test sites at planting time.

Vertical Distribution of Rotylenchulus reniformis in Cotton Fields

The possible impact of Rotylenchulus reniformis below plow depth was evaluated by measuring the vertical distribution of R. reniformis and soil texture in 20 symptomatic fields on 17 farms across six states. The mean nematode population density per field, 0 to 122 cm deep, ranged from 0.4 to 63 nematodes/g soil, and in 15 fields more than half of the R. reniformis present were below 30.5 cm, which is the greatest depth usually plowed by farmers or sampled by consultants. In 11 fields measured, root density was greatest in the top 15 cm of soil; however, roots consistently penetrated 92 to 122 cm deep by midseason, and in five fields in Texas and Louisiana the ratio of nematodes to root-length density within soil increased with depth. Repeated sampling during the year in Texas indicated that up to 20% of the nematodes in soil below 60 cm in the fall survived the winter. Differences between Baermann funnel and sugar flotation extraction methods were not important when compared with field-to-field differences in nematode populations and field-specific vertical distribution patterns. The results support the interpretation that R. reniformis below plow depth can significantly impact diagnosis and treatment of cotton fields infested with R. reniformis.

Rotylenchulus reniformis below Plow Depth Suppresses Cotton Yield and Root Growth

Damage to cotton by Rotylenchulus reniformis below plow depth was evaluated in a sandy clay loam soil at Weslaco, Texas. In December 1999, 14 holes on 51-cm centers were dug 91 cm deep along the planting bed and adjacent furrow and 2 ml of 1,3-dichloropropene was placed 91, 61, and 30 cm deep as each hole was refilled and packed. This technique eliminated 96%, 81%, and 74% of R. reniformis down to 107 cm at distances 0, 25, and 51 cm laterally from the point of application (P </= 0.05), whereas chisel fumigation at 168 liters/ha 43 cm deep reduced nematode numbers only in the top 61 cm (P </= 0.001). Manual placement of fumigant increased yield 92%; chisel fumigation increased yield 88% (P </= 0.005). A second experiment in February 2001 placed fumigant 43 or 81 cm deep, or at both 43 and 81 cm. Holes alone had no significant effect on nematode density at planting, midseason or harvest, on root length density at midseason, or on cotton lint yield. Fumigant at 43 cm reduced nematode numbers above fumigant application depth at planting 94% (P </= 0.02), at midseason 37% (P </= 0.09), and at harvest 0%, increasing yield 57% (P </= 0.002). Fumigant at 81 cm reduced nematode numbers above fumigant application depth at planting 86% (P </= 0.02), at midseason 74% (P </= 0.02), and at harvest 48% (P </= 0.01), increasing yield 53% (P </= 0.002). Fumigating at both 43 and 81 cm reduced nematode numbers above 90 cm 94% at planting and 79% at midseason, increased midseason root-length density 14-fold below 76 cm, and doubled yield (P </= 0.02 in all cases).

Investigation of the Neutron Quantum States in the Earth's Gravitational Field

We studied the neutron quantum states in the potential well formed by the Earth's gravitational field and a horizontal mirror. The estimated characteristic sizes of the neutron wave functions in two lowest quantum states correspond to their expectations with an accuracy of ≈25 %. The spatial density distribution in a standing neutron wave above a mirror was measured for a set of a few lowest quantum states. A position-sensitive neutron detector with an extra high spatial resolution of 1 μm to 2 μm was developed and tested for this particular task. Although this experiment was not designed or optimized to search for an additional short-range force, nevertheless it allowed us to slightly improve the published boundary in the nanometer range of characteristic distances. We studied systematical uncertainties in the chosen "flow-through" method as well as the feasibility to improve further the accuracy in this experiment.

Effect of glucocorticoïd receptor ligands on myosin heavy chains expression in rat skeletal muscles during controllable stress

The influence of agonist (dexamethasone) and antagonist (mifepristone) of glucocorticoïd receptor during controllable painless stress was evaluated on myosin heavy chains expression in three masticatory and two nape rat muscles: anterior digastric (AD), anterior temporalis (AT), masseter superficialis (MS), longissimus capitis (L) and rectus capitis dorsalis major (R). The relative amounts of myosin heavy chain (MHC) protein isoform contained were significantly affected in four muscles studied by dexamethasone and in three muscles studied under mifepristone, versus control during the stress procedure, after only 1 week of treatment. The control group AT muscles contained respectively 18.2% of MHC 2A, 34.5% of MHC 2X and 47.4% of MHC 2B. The effects of dexamethasone and mifepristone were opposite in this muscle: under dexamethasone, the relative proportions of the three isoforms were 14.2, 31.0 and 54.8%: consequently, MHC 2A and 2X decreased with the profit of 2B. Under mifepristone, the relative proportions were 21.1, 36.6 and 42.3% (MHC 2A and 2X increased to the detriment of 2B). The L muscle was not affected by the two treatments and MS muscle was only affected by dexamethasone. Dexamethasone increased MHC 2B to the detriment of MHC 2A in MS, AD and R. Mifepristone and dexamethasone induced the same changes in AD. The mifepristone treatment decreased the MHC 2X profile in R. Under dexamethasone, four muscles exhibited a significantly higher proportion of the more rapid isoforms than under mifepristone. A previous work showed that controllable stress induced a marked increase in the relative expression of MHC 2B in the same skeletal muscles (Martrette et al. , 1998). Our results confirm then a significant participation of glucocorticoïd in MHC isoform expression during controllable stress.

Depth Distribution of Rotylenchulus reniformis Under Different Tillage and Crop Sequence Systems

ABSTRACT The population density of the reniform nematode, Rotylenchulus reniformis, was monitored at depths of 0 to 30, 30 to 60, 60 to 90, and 90 to 120 cm in a tillage and crop sequence trial in south Texas in 2000 and 2001. Main plots were subjected to three different tillage systems: conventional tillage (moldboard plowing and disking), ridge tillage, and no-tillage. Subplots were planted with three different crop sequences: spring cotton and fall corn every year; spring cotton and fall corn in one year, followed by corn for two years; and cotton followed by corn and then grain sorghum, one spring crop per year. The population density of R. reniformis on corn and grain sorghum was low throughout the soil profile. In plots planted with spring cotton and fall corn every year, fewer nematodes were found at depths of 60 to 120 cm in the no-tillage and ridge tillage systems than in the conventional tillage system. Population densities were lower at depths of 0 to 60 cm than at 60 to 120 cm. Soil moisture and cotton root length did not affect nematode population densities in the field. When soil was placed in pots and planted with cotton in the greenhouse, lower population densities developed in soil taken from depths of 0 to 60 cm than in soil from depths of 60 to 120 cm. Final nematode populations were similar in size in soil from the different tillage systems, but reproductive factors were higher in soil from plots with reduced-tillage systems than in soil from plots with conventional tillage. Reduced-tillage practices lowered the risk of increases in R. reniformis populations and reduced population densities following 2 years of non-hosts throughout soil depths, but population densities resurged to the same high levels as in soil planted with cotton every year during one season of cotton.

Quantum states of neutrons in the Earth's gravitational field

The discrete quantum properties of matter are manifest in a variety of phenomena. Any particle that is trapped in a sufficiently deep and wide potential well is settled in quantum bound states. For example, the existence of quantum states of electrons in an electromagnetic field is responsible for the structure of atoms, and quantum states of nucleons in a strong nuclear field give rise to the structure of atomic nuclei. In an analogous way, the gravitational field should lead to the formation of quantum states. But the gravitational force is extremely weak compared to the electromagnetic and nuclear force, so the observation of quantum states of matter in a gravitational field is extremely challenging. Because of their charge neutrality and long lifetime, neutrons are promising candidates with which to observe such an effect. Here we report experimental evidence for gravitational quantum bound states of neutrons. The particles are allowed to fall towards a horizontal mirror which, together with the Earth's gravitational field, provides the necessary confining potential well. Under such conditions, the falling neutrons do not move continuously along the vertical direction, but rather jump from one height to another, as predicted by quantum theory.

Influence of the Lurcher mutation on myosin heavy chain expression in skeletal and cardiac muscles

This study evaluated the influence of Lurcher mutation, characterized by degeneration of cerebellar Purkinje cells, granule cells, and inferior olive neurons, on cardiac and skeletal muscles: one respiratory (diaphragm, Dia), three masticatory (anterior temporalis, AT; masseter superficialis, MS and anterior digastric, AD), one hind limb (soleus, S), entire tongue (T), and one cardiac (ventricle, V) muscles. Body and muscle weight, muscle protein content, and myosin heavy chain (MHC) isoforms relative expression were then compared in Lurcher mutant mice vs. normal, according to sex. Male body weight was always greater than female one, but there was no specific muscle difference in females, except for T relative weight which was greater in normal females. Muscle protein concentration was greater in normal males except for AD and T in which it was lower. Lurcher mutant mice showed a reduced whole body growth but no specific muscle atrophy (except in male AT), and a global decrease in muscle protein content which made muscles more fragile (except in female Dia and male T, in which it was greater). Lurcher mutation induced a global reduction of muscle protein concentration whereas a general influence of sex could not be disclosed. Concerning MHC relative composition, all the muscles were fast-twitch: Dia, AT, MS, AD, S, and T predominantly expressed the fast type 2 MHC isoforms, except female S, whereas V contained only MHC alpha, also a fast MHC. Female muscles were slower than male ones and classification of muscles in terms of shortening velocity was comparable in normal male and female. In other respects, male Lurcher mutant muscles were slower and consequently more fatigue resistant than normal, except T which became faster and less fatigue resistant. On the contrary, in female mutants, only the Dia was slower than normal one, MS and AD were comparable to normal ones and finally, AT, S, and T were faster than normal ones. It should be noted that a developmental MHC (neonatal) was present in Lurcher AD. Motor control, which influences muscle structure, is altered in Lurcher mutant and could be one of the causal factor of the fast-to-slow MHC switches observed in some mutant muscles. It seems therefore that cerebellar Purkinje cells, granule cells, and inferior olive neurons are very important in maintaining the structural integrity of both cardiac and skeletal muscle, and their degeneration is accompanied by important muscles modifications. J. Cell. Biochem. Suppl. 36: 222-231, 2001.

Impact of vascular branching sites on focal progression of allograft vasculopathy in transplanted hearts

BACKGROUND

Cardiac allograft vascular disease (CAVD) represents one of the most accelerated progressing coronary syndromes in the human heart. A variety of risk factors have been identified over recent years; however, little is known about the influence of physical forces. As a model for differences in focal blood flow dynamics, we analyzed progression of intimal hyperplasia at vascular bifurcational sites using intravascular ultrasound (IVUS).

METHODS

The most diseased vascular sites ("worst sites") in 59 coronary arteries were assessed (30 MHz, motorized pull back) in 25 consecutive heart transplant recipients at baseline (52.8+/-15.3 days postoperatively) and after 1 year of follow up (360.5+/-24.9 days). Progression of intimal hyperplasia was compared between branching and non-branching lesions as well as in focal relation to the position of the flow divider.

RESULTS

A total of 41 (69.5%) worst sites were identified at branching locations. Progression of intimal hyperplasia was found to be significantly more severe at bifurcational sites with an increase in plaque area by 1.5+/-1.8 mm(2) in branching versus 0.4+/-0.6 mm(2) in non-branching lesions (P=0.015). The highest rate in focal progression was found at the opposite site of the flow divider with an increase in maximal intimal thickness by 0.3+/-0.23 mm (180 degrees ) as compared to 0.11+/-0.15 mm (90 degrees, P<0.001) and 0.15+/-0.15 mm (P=0.014) at 270 degrees.

CONCLUSIONS

Using serial intravascular ultrasound examinations, vascular branching sites could be identified to be predisposing locations not only for a donor related arteriosclerosis, but also for progression of intimal hyperplasia within transplanted hearts. The highest regional increase in intimal thickness was found at the outer wall of the flow divider, suggesting focal shear or wall stress to be involved in pathogenesis.