Molecular profiling of the hippocampus of children with autism spectrum disorder

Several lines of evidence point to a key role of the hippocampus in Autism Spectrum Disorders (ASD). Altered hippocampal volume and deficits in memory for person and emotion related stimuli have been reported, along with enhanced ability for declarative memories. Mouse models have demonstrated a critical role of the hippocampus in social memory dysfunction, associated with ASD, together with decreased synaptic plasticity. Chondroitin sulfate proteoglycans (CSPGs), a family of extracellular matrix molecules, represent a potential key link between neurodevelopment, synaptic plasticity, and immune system signaling. There is a lack of information regarding the molecular pathology of the hippocampus in ASD. We conducted RNAseq profiling on postmortem human brain samples containing the hippocampus from male children with ASD (n = 7) and normal male children (3-14 yrs old), (n = 6) from the NIH NeuroBioBank. Gene expression profiling analysis implicated molecular pathways involved in extracellular matrix organization, neurodevelopment, synaptic regulation, and immune system signaling. qRT-PCR and Western blotting were used to confirm several of the top markers identified. The CSPG protein BCAN was examined with multiplex immunofluorescence to analyze cell-type specific expression of BCAN and astrocyte morphology. We observed decreased expression of synaptic proteins PSD95 (p < 0.02) and SYN1 (p < 0.02), increased expression of the extracellular matrix (ECM) protease MMP9 (p < 0.03), and decreased expression of MEF2C (p < 0.03). We also observed increased BCAN expression with astrocytes in children with ASD, together with altered astrocyte morphology. Our results point to alterations in immune system signaling, glia cell differentiation, and synaptic signaling in the hippocampus of children with ASD, together with alterations in extracellular matrix molecules. Furthermore, our results demonstrate altered expression of genes implicated in genetic studies of ASD including SYN1 and MEF2C.

Non-cellulosic polysaccharide content in feed ingredients and ileal and total tract non-cellulosic polysaccharide digestibility in 21- and 42-day-old broilers fed diets with and without added composite enzymes

An initial study profiled non-cellulosic polysaccharide (NCP) levels in feed ingredient samples-corn, soybean meal (SBM), whole soybean, and distillers dried grains with solubles (DDGS). A separate NCP digestibility assay was performed in broilers at day 21 (grower phase) and day 42 (finisher phase) fed corn-soy based diets with and without composite enzymes (phytases, multi-carbohydrases, and proteases). Negative control (NC), NC + composite enzymes (NC+E), and positive control (PC) diets were tested. Negative control and NC + E diets were isocaloric, 3,020 kcal/kg ME at grower phase and 3,026 kcal/kg ME at finisher phase. Positive control diet was formulated to meet the Cobb standard nutrient specifications. Diets, pooled digesta, and excreta samples from all treatment diets were collected from 21- and 42-day-old birds and NCP content analyzed as soluble NCP (S-NCP) and insoluble NCP (I-NCP) fractions. Digestibility coefficient (DC) values were determined for all dietary treatments for both the feeding periods. Results from the ingredient analysis showed NCP levels of ∼7 to 10% in corn samples, ∼8 to 11% in SBM samples, ∼11 to 14% (including pectin level) in whole soybean, and ∼12 to 17% in DDGS samples, suggesting variation (P < 0.05) in NCP levels existed within ingredient samples. Digestibility assays showed that enzyme treated (NC + E) diet improved DC values at day 21 from 6 to 10 units and 6 to 9 units for ileal and total tract collection, respectively, for I-NCP fraction (P < 0.05) compared to DC values for NC or PC diets. The ileal DC values at day 42 were not different between treatment diets (∼0.6) but total tract DC values improved 9 to 11 units for broilers fed NC + E diet compared to NC or PC diets. Higher DC values for S-NCP were observed for all treatments for both feeding periods (∼0.7-ileal and ∼0.8-total tract) compared to DC values for I-NCP. Overall, the use of supplemental enzymes in corn-soy-based diets showed improvement in total NCP digestion.

A patient tumour-on-a-chip system for personalised investigation of radiotherapy based treatment regimens

Development of personalised cancer models to predict response to radiation would benefit patient care; particularly in malignancies where treatment resistance is prevalent. Herein, a robust, easy to use, tumour-on-a-chip platform which maintains precision cut head and neck cancer for the purpose of ex vivo irradiation is described. The device utilises sintered discs to separate the biopsy and medium, mimicking in vivo microvascular flow and diffusion, maintaining tissue viability for 68 h. Integrity of tissues is demonstrated by the low levels of lactate dehydrogenase release and retained histology, accompanied by assessment of cell viability by trypan blue exclusion and flow cytometry; fluid dynamic modelling validates culture conditions. An irradiation jig is described for reproducible delivery of clinically-relevant doses (5 × 2 Gy) to newly-presenting primary tumours (n = 12); the addition of concurrent cisplatin is also investigated (n = 8) with response analysed by immunohistochemistry. Fractionated irradiation reduced proliferation (BrdU, p = 0.0064), increased DNA damage (ƴH2AX, p = 0.0043) and caspase-dependent apoptosis (caspase-cleaved cytokeratin-18) compared to control; caspase-dependent apoptosis was further increased by concurrent cisplatin compared to control (p = 0.0063). This is a proof of principle study showing the response of cancer tissue to irradiation ex vivo in a bespoke system. The novel platform described has the potential to personalise treatment for patients in a cost-effective manner with applicability to any solid tumour.

Is childhood OCD a risk factor for eating disorders later in life? A longitudinal study

BACKGROUND

It has been suggested that childhood obsessive-compulsive disorder (OCD) may be a risk factor for the development of an eating disorder (ED) later in life, but prospective studies are lacking. We aimed to determine the prevalence of ED at follow-up and clinical predictors in a longitudinal clinical sample of adolescents/young adults diagnosed with OCD in childhood.

METHOD

All contactable (n=231) young people with OCD assessed over 9 years at a national and specialist paediatric OCD clinic were included in this study. At follow-up, 126 (57%) young people and parents completed the ED section of the Developmental and Well-being Assessment. Predictors for ED were investigated using logistic regression.

RESULTS

In total, 16 participants (12.7%) had a diagnosis of ED at follow-up. Having an ED was associated with female gender and persistent OCD at follow-up. There was a trend for family history of ED being predictive of ED diagnosis. Five (30%) of those who developed an ED at follow-up had ED symptoms or food-related obsessions/compulsions at baseline. A difference in predictors for an ED versus other anxiety disorders at follow-up was identified.

CONCLUSIONS

This study provides initial evidence that baseline clinical predictors such as female gender and family history of ED might be specific to the later development of ED in the context of childhood OCD. Clinicians should be alert to ED subthreshold symptoms in young girls presenting with OCD. Future longitudinal studies are needed to clarify the relationship between childhood OCD and later ED.

Long-term outcomes of obsessive-compulsive disorder: follow-up of 142 children and adolescents

BACKGROUND

Obsessive-compulsive disorder (OCD) often starts in childhood and adolescence and can be a chronic disorder with high persistence rates. There are few prospective long-term follow-up studies.

AIMS

To follow up young people with OCD to clarify persistence rates and relevant predictors, presence of other psychiatric disorders, functional impairment, service utilisation and perceived treatment needs.

METHOD

All young people with OCD assessed over 9 years at the National and Specialist Paediatric OCD clinic, Maudsley Hospital, London, were included. Sixty-one per cent (142 of 222) of all contactable young people and parents completed computerised diagnostic interviews and questionnaires.

RESULTS

We found a persistence rate of OCD of 41%; 40% of participants had a psychiatric diagnosis other than OCD at follow-up. The main predictor for persistent OCD was duration of illness at assessment. High levels of baseline psychopathology predicted other psychiatric disorders at follow-up. Functional impairment and quality of life were mildly to moderately affected. Approximately 50% of participants were still receiving treatment and about 50% felt a need for further treatment.

CONCLUSIONS

This study confirms that paediatric OCD can be a chronic condition that persists into adulthood. Early recognition and treatment might prevent chronicity. Important challenges for services are ensuring adequate treatment and a smooth transition from child to adult services.

Alpha-synuclein deficiency in the C57BL/6JOlaHsd strain does not modify disease progression in the ME7-model of prion disease

We previously detailed how intrahippocampal inoculation of C57BL/6J mice with murine modified scrapie (ME7) leads to chronic neurodegeneration (Cunningham C, Deacon R, Wells H, Boche D, Waters S, Diniz CP, Scott H, Rawlins JN, Perry VH (2003) Eur J Neurosci 17:2147-2155.). Our characterization of the ME7-model is based on inoculation of this murine modified scrapie agent into C57BL/6J mice from Harlan laboratories. This agent in the C57BL/6J host generates a disease that spans a 24-week time course. The hippocampal pathology shows progressive misfolded prion (PrP(Sc)) deposition, astrogliosis and leads to behavioural dysfunction underpinned by the early synaptic loss that precedes neuronal death. The Harlan C57BL/6J, although widely used as a wild type mouse, are a sub-strain harbouring a spontaneous deletion of alpha-synuclein with the full description C57BL/6JOlaHsd. Recently alpha-synuclein has been shown to ameliorate the synaptic loss in a mouse model lacking the synaptic chaperone CSP-alpha. This opens a potential confound of the ME7-model, particularly with respect to the signature synaptic loss that underpin the physiological and behavioural dysfunction. To investigate if this strain-selective loss of a candidate disease modifier impacts on signature ME7 pathology, we compared cohorts of C57BL/6JOlaHsd (alpha-synuclein negative) with the founder strain from Charles Rivers (C57BL/6JCrl, alpha-synuclein positive). There were subtle changes in behaviour when comparing control animals from the two sub-strains indicating potentially significant consequences for studies assuming neurobiogical identity of both strains. However, there was no evidence that the absence of alpha-synuclein modifies disease. Indeed, accumulation of PrP(Sc), synaptic loss and the behavioural dysfunction associated with the ME7-agent was the same in both genetic backgrounds. Our data suggest that alpha-synuclein deficiency does not contribute to the compartment specific processes that give rise to prion disease mediated synaptotoxicity and neurodegeneration.

Normal values for distortion product otoacoustic emissions in children: a study using primary levels previously demonstrated to be optimum for identification of hearing loss

No published data exist for normal values of distortion product otoacoustic emissions (DPOAE) in children at primary levels f1 = 65 dB and f2 = 55 dB SPL. These primary levels have been previously demonstrated to be optimal for identification of hearing impaired ears in adults. A total of 102 normal children underwent audiological assessment, including exclusion of middle ear disease, pure tone audiometry and DPOAE DP-grams (primaries L1/L2 = 65/55 dB SPL, f1:f2 = 1.22). There was a statistically significant decrease in DPOAE amplitude with increasing age. DPOAE amplitude was also dependent on the frequency of f2. However, there was wide inter- and intra-individual variation in DPOAE amplitude at different frequencies of f2. There was also a large overlap between the range of values of DPOAE amplitude between the adjacent age groups. Detailed assessment of DPOAE in children is feasible in the clinical setting. These normal values should prove invaluable in future studies; however, the large range of normal values means that cross-sectional studies may not be able to detect small variations in cochlear function.

Developmental potential of mouse primordial germ cells

There are distinctive and characteristic genomic modifications in primordial germ cells that distinguish the germ cell lineage from somatic cells. These modifications include, genome-wide demethylation, erasure of allele-specific methylation associated with imprinted genes, and the re-activation of the X chromosome. The allele-specific differential methylation is involved in regulating the monoallelic expression, and thus the gene dosage, of imprinted genes, which underlies functional differences between parental genomes. However, when the imprints are erased in the germ line, the parental genomes acquire an equivalent epigenetic and functional state. Therefore, one of the reasons why primordial germ cells are unique is because this is the only time in mammals when the distinction between parental genomes ceases to exist. To test how the potentially imprint-free primordial germ cell nuclei affect embryonic development, we transplanted them into enucleated oocytes. Here we show that the reconstituted oocyte developed to day 9.5 of gestation, consistently as a small embryo and a characteristic abnormal placenta. The embryo proper also did not progress much further even when the inner cell mass was ‘rescued’ from the abnormal placenta by transfer into a tetraploid host blastocyst. We found that development of the experimental conceptus was affected, at least in part, by a lack of gametic imprints, as judged by DNA methylation and expression analysis of several imprinted genes. The evidence suggests that gametic imprints are essential for normal development, and that they can neither be initiated nor erased in mature oocytes; these properties are unique to the developing germ line.

Epigenotype switching of imprintable loci in embryonic germ cells

Expression of imprinted genes is dependent on their parental origin. This is reflected in the heritable differential methylation of parental alleles. The gametic imprints are however reversible as they do not endure for more than one generation. To investigate if the epigenetic changes in male and female germ line are similar or not, we derived embryonic germ (EG) cells from primordial germ cells (PGCs) of day 11.5 and 12.5 male and female embryos. The results demonstrate that they have an equivalent epigenotype. First, chimeras made with EG cells derived from both male and female embryos showed comparable fetal overgrowth and skeletal abnormalities, which are similar to but less severe than those induced by androgenetic embryonic stem (ES) cells. Thus, EG cells derived from female embryos resemble androgenetic ES cells more than parthenogenetic cells. Furthermore, the methylation status of both alleles of a number of loci in EG cells was similar to that of the paternal allele in normal somatic cells. Hence, both alleles of Igf2r region 2, Peg1/Mest, Peg3, Nnat were consistently unmethylated in EG cells as well as in the primary embryonic fibroblasts (PEFs) rescued from chimeras. More strikingly, both alleles of p57kip2 that were also unmethylated in EG cells, underwent de novo methylation in PEFs to resemble a paternal allele in somatic cells. The exceptions were the H19 and Igf2 genes that retained the methylation pattern in PEFs as seen in normal somatic tissues. These studies suggest that the initial epigenetic changes in germ cells of male and female embryos are similar.

Structure and expression of the mouse L23mrp gene downstream of the imprinted H19 gene: biallelic expression and lack of interaction with the H19 enhancers

The human L23 (mitochondrial)-related protein gene, located 40 kb downstream of the imprinted H19 gene, is biallelically expressed. We have cloned and characterized its mouse homolog, L23mrp, which maps to the conserved syntenic region on mouse chromosome 7. The promoter of L23mrp is a CpG island that is transcribed ubiquitously, but at different levels, in different fetal tissues. Allele-specific expression analysis revealed that both parental alleles are equally active. Since the enhancers located between H19 and L23mrp had been shown to be involved in the imprinted expression of Ins-2, Igf-2, and H19, we asked whether they also influence L23mrp. Analysis of mice with a targeted deletion of the enhancers demonstrated that they were not disrupted in the expression of L23mrp. These findings indicate that L23mrp is functionally insulated from the Ins-2/Igf-2/H19 domain in terms of both imprinting and enhancer action.

Efficacy of immediate postirrigation culture in the treatment of upper-extremity abscesses

A retrospective chart review of 192 patients of the musculoskeletal infection ward at the authors' facility was performed to assess the value of immediate postirrigation cultures in the treatment of acute soft tissue infections of the upper extremity. Twenty-two patients (11.5%) had postirrigation cultures with an organism that was not present in the preirrigation cultures. All of those organisms not previously found were gram-positive organisms, and no changes were necessary in the initial antibiotic regimes. Immediate postirrigation cultures did not prove to be effective in the information they provided related to treatment of acute soft tissue infections of the upper extremity.

A functional analysis of imprinting in parthenogenetic embryonic stem cells

A detailed analysis of the developmental potential of parthenogenetic embryonic stem cells (PGES) was made in vivo and in vitro, and a comparison was made with the development of cells from parthenogenetic embryos (PG). In vivo, in chimeras with normal host cells (N), PGES cells showed a restricted tissue distribution consistent with that of PG cells, suggesting faithful imprinting in PGES cells with respect to genes involved in lineage allocation and differentiation. Restricted developmental potential was also observed in teratomas formed by ectopic transfer under the kidney capsule. In contrast, the classic phenotype of growth retardation normally observed in PG&lt;==&gt;N chimeras was not seen, suggesting aberrant regulation in PGES cells of genes involved in growth regulation. We also analysed the expression of known imprinted genes after ES cell differentiation. Igf2, H19 and Igf2r were all appropriately expressed in the PGES derived cells following induction of differentiation in vitro with all-trans retinoic acid or DMSO, when compared with control (D3) and androgenetic ES cells (AGES). Interestingly, H19 was found to be expressed at high levels following differentiation of the AGES cells. Due to the unexpected normal growth regulation of PGES&lt;==&gt;N chimeras we also examined Igf2 expression in PGES derived cells differentiated in vivo and found that this gene was still repressed. Our studies show that PGES cells provide a valuable in vitro model system to study the effects of imprinting on cell differentiation and they also provide invaluable material for extensive molecular studies on imprinted genes. In addition, the aberrant growth phenotype observed in chimeras has implications for mechanisms that regulate the somatic establishment and maintenance of some imprints. This is of particular interest as aberrant imprinting has recently been invoked in the etiology of some human diseases.