Experimental Quantum Chemistry: A Hammett-inspired Fingerprinting of Substituent Effects.

The quantum mechanically calculable Q descriptor is shown to be a potent quantifier of chemical reactivity in complex molecules - it shows a strong correlation to experimentally derived field effects in non-aromatic substrates and Hammett σm and σp parameters. Models for predicting substituent effects from Q are presented and applied, including on the elusive pentazolyl substituent. The presented approach enables fast computational estimation of substituent effects, and, in extension, medium-throughput screening of molecules and compound design. An experimental dataset is suggested as a candidate benchmark for aiding the general development and comparison of electronic structure analyses. It is here used to evaluate the experimental quantum chemistry (EQC) framework for chemical bonding analysis in larger molecules.

Autism spectrum disorders before diagnosis: results from routine developmental surveillance at 18 months.

AIM: This study investigated the results from the national, routine 18-month developmental surveillance at Child Healthcare Centres (CHCs) on children later diagnosed with autism spectrum disorder (ASD). METHODS: Child Healthcare Centre records of 175 children, diagnosed with ASD before 4.5 years in Stockholm County, Sweden, were reviewed regarding the results of the eight-item neurodevelopmental surveillance. Results were contrasted with normative data from the general child population in Stockholm County. RESULTS: More than one-third of the total ASD group, including half of the group with ASD and intellectual disability (ID), did not pass the required number of items, compared to one in 50 in the general child population. Of those with ASD and ID who had passed, more than one-third experienced developmental regression after 18 months of age. If the CHC surveillance had considered reported regulatory problems - crying, feeding and sleeping - then another 10% of the children with ASD and ID could have been identified during this surveillance. CONCLUSION: The existing CHC surveillance traced half of the group of children who were later diagnosed with ASD combined with intellectual disability. Adding an item on regulatory problems to the 18-month surveillance would have increased this number by another 10%.

X-ray tensor tomography for small-grained polycrystals with strong texture.

Small-angle X-ray tensor tomography and the related wide-angle X-ray tensor tomography are X-ray imaging techniques that tomographically reconstruct the anisotropic scattering density of extended samples. In previous studies, these methods have been used to image samples where the scattering density depends slowly on the direction of scattering, typically modeling the directionality, i.e. the texture, with a spherical harmonics expansion up until order ℓ = 8 or lower. This study investigates the performance of several established algorithms from small-angle X-ray tensor tomography on samples with a faster variation as a function of scattering direction and compares their expected and achieved performance. The various algorithms are tested using wide-angle scattering data from an as-drawn steel wire with known texture to establish the viability of the tensor tomography approach for such samples and to compare the performance of existing algorithms.

Autism before diagnosis: crying, feeding and sleeping problems in the first two years of life.

AIM: To chart early registered regulatory problems (RP) in a representative group of young children with and without autism spectrum disorder (ASD). METHODS: The target group comprised 208 preschool children with ASD, whose records from the Child Health Centres (CHC) were reviewed regarding numbers of consultations for excessive crying, feeding and sleeping problems. The records from an age- and gender-matched comparison group were obtained from the same CHCs as those of the index children RESULTS: Significant differences between the ASD and comparison groups were found for each domain studied and when domains were collapsed. Two or more consultations had occurred in 44% of the children in the ASD group and in 16% of the comparison group (p < 0.001). No correlations were found with regard to gender, later severity of autism, cognitive level or degree of hyperactivity. CONCLUSION: Regulatory problems (RP) were much more common in children who later received a diagnosis of ASD. Children with many RP in infancy require attention from CHC and paediatric services and need to be followed with regard to development and family support.

Multiscale X-ray imaging and characterisation of pharmaceutical dosage forms.

A correlative, multiscale imaging methodology for visualising and quantifying the morphology of solid dosage forms by combining ptychographic X-ray computed nanotomography (PXCT) and scanning small- and wide-angle X-ray scattering (S/WAXS) is presented. The methodology presents a workflow for multiscale analysis, where structures are characterised from the nanometre to millimetre regime. Here, the method is demonstrated by characterising a hot-melt extruded, partly crystalline, solid dispersion of carbamazepine in ethyl cellulose. Characterisation of the morphology and solid-state phase of the drug in solid dosage forms is central as this affects the performance of the final formulation. The 3D morphology was visualised at a resolution of 80 nm over an extended volume through PXCT, revealing an oriented structure of crystalline drug domains aligned in the direction of extrusion. Scanning S/WAXS showed that the nanostructure is similar over the cross section of the extruded filament, with minor radial changes in domain sizes and degree of orientation. The polymorphic forms of carbamazepine were qualified with WAXS, showing a heterogeneous distribution of the metastable forms I and II. This demonstrates the methodology for multiscale structural characterization and imaging to enable a better understanding of the relationships between morphology, performance, and processing conditions of solid dosage forms.

Screening of hydrogen bonds in modified cellulose acetates with alkyl chain substitutions.

This study aimed to elucidate how the glass transition temperature and water interactions in cellulose esters are affected by the structures of their side chains. Cellulose acetate, cellulose acetate propionate and cellulose acetate butyrate with three fractions of butyrates, all having the same total degree of substitution, were selected, and hot-melt pressed. The degree of substitution, structural properties, and water interactions were determined. The Hansen solubility parameters were calculated and showed that the dispersive energy dominates the total cohesive energy, followed by hydrogen bonding and polar energy. The glass transition temperature (Tg) decreased, counter-intuitively, with an increased total cohesive energy, which can be explained by the short-range hydrogen bonds being screened by the increased length of the substituents. The solubility and penetration of water in the cellulose esters decreased with increased side chain length, although the hydrogen bonding energies for all the esters were approximately constant.

Enabling modular dosage form concepts for individualized multidrug therapy: Expanding the design window for poorly water-soluble drugs.

Multidrug dosage forms (aka combination dosage forms, polypills, etc.) create value for patients through reduced pill burdens and simplified administration to improve adherence to therapy. Enhanced flexibility of multidrug dosage forms would provide further opportunities to better match emerging needs for individualized therapy. Through modular dosage form concepts, one approach to satisfy these needs is to adapt multidrug dosage forms to a wider variety of drugs, each with a variety of doses and release profiles. This study investigates and technically explores design requirements for extending the capability of modular multidrug dosage form concepts towards individualization. This builds on our recent demonstration of independent tailoring of dose and drug release, which is here extended towards poorly water-soluble drugs. The challenging design requirement of carrying higher drug loads in smaller volumes to accommodate multiple drugs at their clinical dose is here met regarding dose and release performance. With a modular concept, we demonstrate high precision (<5% RSD) in dose and release performance of individual modules containing felodipine or naproxen in Kollidon VA64 at both a wide drug loading range (5% w/w and 50% w/w drug) and a small module size (3.6 mg). In a forward-looking design-based discussion, further requirements are addressed, emphasizing that reproducible individual module performance is predictive of dosage form performance, provided the modules are designed to act independently. Therefore, efforts to incorporate progressively higher drug loads within progressively smaller module volumes will be crucial to extend the design window further towards full flexibility of future dosage forms for individualized multidrug therapy.

Prevalence of autism in children of Somali origin living in Stockholm: brief report of an at-risk population.

This work was a follow-up study (birth years 1999-2003) of the prevalence of autism in children of Somali background living in the county of Stockholm, Sweden. In a previous study (birth years 1988-98), the prevalence of autism associated with learning disability* was found to be three to four times higher among Somali children compared with other ethnicities in Stockholm. We examined all records of children of Somali background, born from 1999 to 2003, registered at the centre for schoolchildren with autism and learning disability. The census day was 31 December 2009. The prevalence of autism and PDDNOS (with learning disability) was 0.98% (18/1836) in the Somali group and 0.21% (232/111555) in the group of children of non-Somali origin (p<0.001). The increased prevalence remained and was now between four and five times higher in children of Somali background. A clinical observation was that more than 80%, in addition to autism and learning disability, had a profound hyperactivity. The findings accord with many other studies reporting higher prevalence rates of autism in children of immigrant mothers. We discuss the need for further research of underlying mechanisms.

Serum levels of 25-hydroxyvitamin D in mothers of Swedish and of Somali origin who have children with and without autism.

AIM: To analyse serum levels of 25-hydroxyvitamin D in mothers of Somali origin and those of Swedish origin who have children with and without autism as there is a growing evidence that low vitamin D impacts adversely on brain development. METHOD: Four groups of mothers were invited to participate; 20 with Somali origin with at least one child with autism, 20 with Somali origin without a child with autism, 20 of Swedish origin with at least one child with autism and 20 with Swedish origin without a child with autism. Two blood samples were collected from each individual; during autumn and spring. RESULTS: Between 12 and 17 mothers from the different groups accepted to participate, both groups of mothers of Somali origin had significantly lower values of 25-hydroxyvitamin D compared with Swedish mothers. The difference of 25-hydroxyvitamin D between mothers of Somali origin with and without a child with autism was not significant. CONCLUSION: Our findings of low vitamin D levels in Somali women entail considerable consequences in a public health perspective. The observed tendency, i.e. the lowest values in mothers of Somali origin with a child with autism was in the predicted direction, supporting the need for further research of vitamin D levels in larger samples of Somali mothers of children with and without autism.

Autism With and Without Regression: A Two-Year Prospective Longitudinal Study in Two Population-Derived Swedish Cohorts.

Two community-based cohorts of children with autism spectrum disorder, examined using similar assessment protocols, were pooled (n = 301) and subdivided according to history of regression. Those with regression (n = 62), 20.5% of the combined cohort, were contrasted with those without regression (n = 241) at first assessment (age range 19-60 months) and at 2-year follow-up on a range of measures. The regression group was significantly more functionally impaired, with regard to intellectual function (p < .001), language development (p < .001), and to severity of autism (p < .01) at both T1 and T2. Only 14 (23.3%) had a clearly identified underlying etiology [24 (18.6%) in the non-regressive group]. There were no significant differences between those who had regressed 'from normal' and those who had regressed 'from low' functioning.

Children with borderline intellectual functioning and autism spectrum disorder: developmental trajectories from 4 to 11 years of age.

BACKGROUND: Studies on autism have tended to focus either on those with intellectual disability (ie, those with intellectual quotient [IQ] under 70) or on the group that is referred to as "high-functioning", that is, those with borderline, average or above average IQ. The literature on cognition and daily functioning in autism spectrum disorder combined specifically with borderline intellectual functioning (IQ 70-84) is limited. METHODS: From a representative group of 208 preschool children diagnosed with autism spectrum disorder, those 50 children in the group with borderline intellectual functioning at ages 4.5-6.5 years were targeted for follow-up at a median age of 10 years. A new cognitive test was carried out in 30 children. Parents were interviewed with a semi-structured interview together with the Vineland Adaptive Behavior Scales (n=41) and the Autism-Tics, attention-deficit/hyperactivity disorder (AD/HD) and other comorbidities inventory (A-TAC) (n=36). RESULTS: Most children of interviewed parents presented problems within several developmental areas. According to A-TAC and the clinical interview, there were high rates of attention deficits and difficulties with regulating activity level and impulsivity. Vineland Adaptive Behavior Scales composite scores showed that at school age, a majority of the children had declined since the previous assessment at ages between 4.5 and 6.5 years. Almost half the tested group had shifted in their IQ level, to below 70 or above 84. CONCLUSION: None of the children assessed was without developmental/neuropsychiatric problems at school-age follow-up. The results support the need for comprehensive follow-up of educational, medical and developmental/neuropsychiatric needs, including a retesting of cognitive functions. There is also a need for continuing parent/family follow-up and support.

Epigenetic Regulation of Tissue-Type Plasminogen Activator in Human Brain Tissue and Brain-Derived Cells.

The serine protease tissue-type plasminogen activator (t-PA) is involved in both vital physiological brain processes, such as synaptic plasticity, and pathophysiological conditions, such as neurodegeneration and ischemic stroke. Recent data suggest that epigenetic mechanisms play an important role in the regulation of t-PA in human endothelial cells. However, there are limited data on epigenetic regulation of t-PA in human brain-derived cells. We demonstrate that treatment of cultured human neurons and human astrocytes with the histone deacetylase inhibitors trichostatin A (TSA) and MS-275 resulted in a two- to threefold increase in t-PA mRNA and protein expression levels. Next, we performed a chromatin immunoprecipitation assay on treated astrocytes with antibodies directed against acetylated histones H3 and H4 (both markers of gene activation). Treatment with MS-275 and TSA for 24 hours resulted in a significant increase in H3 acetylation, which could explain the observed increase in t-PA gene activity after the inhibition of histone deacety-lation. Furthermore, DNA methylation analysis of cultured human neurons and astrocytes, as well as human postmortem brain tissue, revealed a stretch of unmethylated CpG dinucleotides in the proximal t-PA promoter, whereas more upstream CpGs were highly methylated. Taken together, these results implicate involvement of epigenetic mechanisms in the regulation of t-PA expression in the human brain.

"Recovery" from the diagnosis of autism - and then?

BACKGROUND: The aim of this study was to follow up the 17 children, from a total group of 208 children with autism spectrum disorder (ASD), who "recovered from autism". They had been clinically diagnosed with ASD at or under the age of 4 years. For 2 years thereafter they received intervention based on applied behavior analysis. These 17 children were all of average or borderline intellectual functioning. On the 2-year follow-up assessment, they no longer met criteria for ASD. METHODS: At about 10 years of age they were targeted for a new follow-up. Parents were given a semistructured interview regarding the child's daily functioning, school situation, and need of support, and were interviewed using the Vineland Adaptive Behavior Scales (VABS) and the Autism - Tics, Attention-deficit/hyperactivity disorder (AD/HD), and other Comorbidities (A-TAC) telephone interview. RESULTS: The vast majority of the children had moderate-to-severe problems with attention/activity regulation, speech and language, behavior, and/or social interaction. A majority of the children had declined in their VABS scores. Most of the 14 children whose parents were A-TAC-interviewed had problems within many behavioral A-TAC domains, and four (29%) had symptom levels corresponding to a clinical diagnosis of ASD, AD/HD, or both. Another seven children (50%) had pronounced subthreshold indicators of ASD, AD/HD, or both. CONCLUSION: Children diagnosed at 2-4 years of age as suffering from ASD and who, after appropriate intervention for 2 years, no longer met diagnostic criteria for the disorder, clearly needed to be followed up longer. About 3-4 years later, they still had major problems diagnosable under the umbrella term of ESSENCE (Early Symptomatic Syndromes Eliciting Neurodevelopmental Clinical Examinations). They continued to be in need of support, educationally, from a neurodevelopmental and a medical point of view. According to parent interview data, a substantial minority of these children again met diagnostic criteria for ASD.

Preschoolers with Autism Spectrum Disorder Followed for 2 Years: Those Who Gained and Those Who Lost the Most in Terms of Adaptive Functioning Outcome.

Clinical predictors of 2-year outcome in preschoolers with ASD were studied in a population-based group of very young children with ASD (n = 208). Children who gained the most (n = 30) and lost the most (n = 23), i.e., increased or decreased their adaptive functioning outcome according to the Vineland Composite Score between study entry (T1) and follow-up (T2), 2 years later were compared. Individual factors that differed significantly between the two outcome groups were cognitive level, age at referral, not passing expected milestones at 18 months, autistic type behavior problems and regression. However, logistic regression analysis showed that only cognitive level at T1 (dichotomized into IQ < 70 and IQ ≥ 70) made a unique statistically significant contribution to outcome prediction (p = <.001) with an odds ratio of 18.01. The findings have significant clinical implications in terms of information at diagnosis regarding clinical prognosis in ASD.

Selective expression of hyaluronan and receptor for hyaluronan mediated motility (Rhamm) in the adult mouse subventricular zone and rostral migratory stream and in ischemic cortex.

Hyaluronan is a large glycosaminoglycan, which is abundant in the extracellular matrix of the developing rodent brain. In the adult brain however, levels of hyaluronan are significantly reduced. In this study, we used neurocan-GFP as a histochemical probe to analyze the distribution of hyaluronan in the adult mouse subventricular zone (SVZ), as well as in the rostral migratory stream (RMS). Interestingly, we observed that hyaluronan is generally downregulated in the adult brain, but notably remains at high levels in the SVZ and RMS; areas in which neural stem/progenitor cells (NSPCs) persist, proliferate and migrate throughout life. In addition, we found that the receptor for hyaluronan-mediated motility (Rhamm) was expressed in migrating neuroblasts in these areas, indicating that Rhamm could be involved in regulating hyaluronan-mediated cell migration. Hyaluronan levels are balanced by synthesis through hyaluronan synthases (Has) and degradation by hyaluronidases (Hyal). We found that Has1 and Has2, as well as Hyal1 and Hyal2 were expressed in GFAP positive cells in the adult rodent SVZ and RMS, indicating that astrocytes could be regulating hyaluronan-mediated functions in these areas. We also demonstrate that hyaluronan levels are substantially increased at six weeks following a photothrombotic stroke lesion to the adult mouse cortex. Furthermore, GFAP positive cells in the peri-infarct area express Rhamm. Thus, hyaluronan may be involved in regulating cell migration in the normal SVZ and RMS and could also be responsible for priming the peri-infarct area following an ischemic lesion for cell migration.

Sensory abnormalities in autism. A brief report.

Sensory abnormalities were assessed in a population-based group of 208 20-54-month-old children, diagnosed with autism spectrum disorder (ASD) and referred to a specialized habilitation centre for early intervention. The children were subgrouped based upon degree of autistic symptoms and cognitive level by a research team at the centre. Parents were interviewed systematically about any abnormal sensory reactions in the child. In the whole group, pain and hearing were the most commonly affected modalities. Children in the most typical autism subgroup (nuclear autism with no learning disability) had the highest number of affected modalities. The children who were classified in an "autistic features" subgroup had the lowest number of affected modalities. There were no group differences in number of affected sensory modalities between groups of different cognitive levels or level of expressive speech. The findings provide support for the notion that sensory abnormality is very common in young children with autism. This symptom has been proposed for inclusion among the diagnostic criteria for ASD in the upcoming DSM-V.

Early intervention in 208 Swedish preschoolers with autism spectrum disorder. A prospective naturalistic study.

Early intervention has been reported to improve outcome in children with autism spectrum disorders (ASDs). Several studies in the field have been randomized controlled trials (RCTs). The aim of this study was to assess ASD outcome in a large naturalistic study. Two hundred and eight children, aged 20-54 months, with a clinical diagnosis of ASD were given intervention and monitored prospectively in a naturalistic fashion over a period of 2 years. The toddlers were considered representative of all but the most severely multiple disabled preschool children with ASD in Stockholm county. They fell into three cognitive subgroups: one with learning disability, one with developmental delay, and one with normal intellectual functioning. Data on intervention type and intensity were gathered prospectively in a systematic fashion. Intervention was classified into intensive applied behaviour analysis (ABA) and non-intensive, targeted interventions, also based on ABA principles. Children were comprehensively assessed by a research team before the onset of intervention, and then, again, 2 years later. Change in Vineland adaptive behaviour scales composite scores from intake (T1) to leaving the study (T2) was set as the primary outcome variable. The research team remained blind to the type and intensity of interventions provided. One hundred and ninety-eight (95%) of the original samples stayed in the study throughout the whole 2-year period and 192 children had a complete Vineland composite score results both at T1 and T2. Vineland composite scores increased over the 2-year period. This increase was accounted for by the subgroup with normal cognitive functioning. There was no significant difference between the intensive and non-intensive groups. Individual variation was considerable, but no child in the study was "problem-free" at follow-up. Our data do not support that children with ASD generally benefit more from the most intensive ABA intervention programs than from less intensive interventions or targeted interventions based on ABA.

Developmental profiles in preschool children with autism spectrum disorders referred for intervention.

The aim was to characterize the panorama of developmental disorders in 208 preschool children with a clinical diagnosis of autism spectrum disorder (ASD), referred to a specialized centre, the Autism Centre for Young Children (ACYC), for intervention. At the centre, a research team examined all children according to structured protocols and interviews. All available test data from their assessments prior to referral were scrutinized. The boy:girl ratio was 5.5:1. In 22% of the total group a period of regression, including speech and language, had occurred. Epilepsy had been diagnosed in 6% of the children. In 38% of the children there was a definite or highly suspected learning disability/mental retardation according to cognitive test results. About the same proportion had a developmental delay that at the time of assessment could not be definitely classified and in 23% there were clear indications of a normal intellectual function. About 40% of the group exhibited hyperactivity. Differences in expressive vocabulary and adaptive functioning were strongly related to cognitive level. About 20% of the group had AD as the dominating developmental disorder, i.e., they represented a clinical picture of "classic" autism. The majority in this group also had learning disability. Another 20%, had ASD combined with a normal intellectual level, some of these conformed to the clinical picture of Asperger syndrome. In a relatively large group (more than half) learning disability or a general developmental delay was as evident as the ASD. In a smaller group (8%) ASD criteria were questionably met. In this group attention deficits in connection with speech and language problems were prominent. The highly individual developmental profiles seen in children with ASDs have to be taken into account when planning intervention and follow-up. The children's medical characteristics also vary considerably and will be detailed in a further report.