Cholinergic denervation attenuates phencyclidine-induced c-fos responses in rat cortical neurons

The cortical cholinergic innervation, which is important for memory and cognition, has been implicated in schizophrenia. To experimentally analyze such a possible role of the cholinergic system, we have used the dissociative drug phencyclidine (PCP), known to produce schizophrenia-like psychosis in humans, to model aspects of schizophrenia in rats. We previously showed that induced cortical cholinergic hypofunction leads to enhanced PCP-induced locomotor activity and attenuated social interaction. After PCP, rats lacking cortical cholinergic innervation also show impaired declarative memory. To directly study the role of the basalo-cortical cholinergic projections for PCP-induced neural activation in different cortical areas, we have now monitored the rapid (30 and 60 min) effects of low doses of PCP (2 and 3mg/kg) on neural activation as reflected by transcriptional activation of c-fos in cortical areas, using quantitative in situ hybridization. We find an almost pan-cortical neural induction of c-fos mRNA with doses of PCP low enough not to alter levels of either BDNF or Nogo receptor mRNA levels. Specific unilateral lesioning of the uncrossed cholinergic projections to the cortical mantle by 192-IgG-saporin immunotoxin delivery to nc basalis (NBM) caused a striking ipsilateral decrease of the PCP-induced cortical c-fos mRNA induction, restricted to areas which had become effectively denervated. Because PCP at low doses is unlikely to directly influence cortical neurons, we suggest that it acts by activation of the cholinergic input, which in turn leads to cortical c-fos mRNA increases. Our results are compatible with a role for the cholinergic system in symptoms of schizophrenia, by showing that the basalo-cortical cholinergic projections are needed in order for PCP to have full activating effects on cortical neurons.

Orbitofrontal dysfunction discriminates behavioral variant frontotemporal dementia from Alzheimer's disease

BACKGROUND

Behavioral variant frontotemporal dementia (bvFTD) patients show prefrontal cortex dysfunction and atrophy.

METHODS

We investigated whether executive function in conjunction with prefrontal cortex atrophy discriminates bvFTD and Alzheimer's disease (AD) patients efficiently at presentation.

RESULTS

AD and bvFTD patients were distinguishable by 89.5% on their performance of 3 executive tasks: the Hayling Test of Inhibitory Control, Digit Span Backward and Letter Fluency. Similarly, scan ratings showed that orbitofrontal cortex (OFC) and dorsolateral prefrontal cortex regions distinguish both patient groups. More importantly, employing the Hayling error score in conjunction with the OFC atrophy rating showed that 92% of patients can be correctly classified into bvFTD and AD.

CONCLUSION

A combination of OFC and disinhibition measures appears to be a powerful diagnostic tool in differentiating bvFTD from AD patients in this preliminary study.

Intragenic rearrangements in NRXN1 in three families with autism spectrum disorder, developmental delay, and speech delay

NRXN1 is highly expressed in brain and has been shown recently to be associated with ASD, schizophrenia, cognitive and behavioral abnormalities, and alcohol and nicotine dependence. We present three families, in whom we identified intragenic rearrangements within NRXN1 using a clinical targeted oligonucleotide array CGH. An approximately 380 kb deletion was identified in a woman with Asperger syndrome, anxiety, and depression and in all four of her children affected with autism, anxiety, developmental delay, and speech delay but not in an unaffected child. An approximately 180 kb tandem duplication was found in a patient with autistic disorder and cognitive delays, and in his mother and younger brother who have speech delay. An approximately 330 kb tandem duplication was identified in a patient with autistic features. As predicted by conceptual translation, all three genomic rearrangements led to the premature truncation of NRXN1. Our data support previous observations that NRXN1 may be pathogenic in a wide variety of psychiatric diseases, including autism spectrum disorder, global developmental delay, anxiety, and depression.

Recurrent reciprocal 16p11.2 rearrangements associated with global developmental delay, behavioural problems, dysmorphism, epilepsy, and abnormal head size

BACKGROUND

Deletion and the reciprocal duplication in 16p11.2 were recently associated with autism and developmental delay.

METHOD

We indentified 27 deletions and 18 duplications of 16p11.2 were identified in 0.6% of all samples submitted for clinical array-CGH (comparative genomic hybridisation) analysis. Detailed molecular and phenotypic characterisations were performed on 17 deletion subjects and ten subjects with the duplication.

RESULTS

The most common clinical manifestations in 17 deletion and 10 duplication subjects were speech/language delay and cognitive impairment. Other phenotypes in the deletion patients included motor delay (50%), seizures ( approximately 40%), behavioural problems ( approximately 40%), congenital anomalies ( approximately 30%), and autism ( approximately 20%). The phenotypes among duplication patients included motor delay (6/10), behavioural problems (especially attention deficit hyperactivity disorder (ADHD)) (6/10), congenital anomalies (5/10), and seizures (3/10). Patients with the 16p11.2 deletion had statistically significant macrocephaly (p<0.0017) and 6 of the 10 patients with the duplication had microcephaly. One subject with the deletion was asymptomatic and another with the duplication had a normal cognitive and behavioural phenotype. Genomic analyses revealed additional complexity to the 16p11.2 region with mechanistic implications. The chromosomal rearrangement was de novo in all but 2 of the 10 deletion cases in which parental studies were available. Additionally, 2 de novo cases were apparently mosaic for the deletion in the analysed blood sample. Three de novo and 2 inherited cases were observed in the 5 of 10 duplication patients where data were available.

CONCLUSIONS

Recurrent reciprocal 16p11.2 deletion and duplication are characterised by a spectrum of primarily neurocognitive phenotypes that are subject to incomplete penetrance and variable expressivity. The autism and macrocephaly observed with deletion and ADHD and microcephaly seen in duplication patients support a diametric model of autism spectrum and psychotic spectrum behavioural phenotypes in genomic sister disorders.

Use of independent genome-wide assays to discover HOXA signature in colon and rectal cancers and validate a role in tumorigenesis

e15014

Background: Rectal cancer differs from colon cancer in terms of prognosis. Here we present genome-wide expression analysis of 79 colon and rectal tumors and gene dosage analysis of 34 archival colorectal tumors in paraffin (FFPE). Methods: Expression data were acquired ( http://expo.intgen.org/geo/home.do ) from Affymetrix experiments analyzed with GeneSpring software version 7.3 (Silicon Genetics, CA). Expression data were normalized ’per chip’ normalized to the 50th percentile of all values; and ’per gene’ normalized to the median expression level across all samples. Expression Project for Oncology (expO) samples included colon (n=50) and rectum (n=29). Differentially expressed genes were identified by parametric test for which variances were not assumed equal (Welch ANOVA). Array comparative genomic hybridization (aCGH) were performed separately on an independent set of FFPE colorectal tumors (n=34) by 244 K microarrays for CGH, Agilent Technologies, CA and with platform embedded analyses tools of CGH Analytics software and ADM-1 bioinformatics. Functional assay by knockout of HOXA9 promoter by lentiviral sh-RNAi construct was performed on colon cancer cell lines shown to have increased HOXA9 dosage and expression. Results: The analysis of expO colon and rectal cancers generated 42 genes with significant differential expression, 26 showed an increased expression of > 2 fold in colon versus rectal samples. Transcription factor family HOXA9 was the most highly expressed (3.8 fold) in colon versus rectal cancer. The aCGH data showed a low level gain of the HOXA gene to be the most frequent dosage alteration (38%). Validation by IHC and qRT-PCR showed 80% and 76% concordance, respectively. Functional assay by sh-RNAi in cell lines (compared to vehicle only) showed marked decrease in cellular viability (40 to 60%), marked morphologic change and a significantly increased apoptotic rate. Conclusion: Multiple genome-wide assays have identified HOXA9 as differentially dosed and expressed in colon and rectal tumors. Compelling functional data from sh-RNAi experiments suggests a tumorigenic role for HOXA9 in altered apoptosis.

No significant financial relationships to disclose.

Clinical evaluation of nitric oxide responses to anti-VEGF therapy with bevacizumab

14039

Background: Anti-vascular endothelial growth factor (anti-VEGF) therapy has been linked to hypertension (HTN) and arterial thrombo-embolic events that may involve changes in nitric oxide (NO) bioavailability. Methods: 25 patients (pts) with advanced cancer, normal renal function and blood pressure (BP), no increased risks for anti-VEGF toxicities, and not on medications known to confound biomarker studies (including anti-hypertensives) were treated with bevacizumab (BV) 15mg/kg d1, then 10mg/kg q2 week. Prior to biomarker assessment, all patients were placed on a calorie-, nitrate-, and salt-restricted diet for 72 hr. All measures were taken pre-treatment (preRx) and on day 28 of treatment (onRx). Dependant variables included; a) Brachial artery reactivity (BAR) following hyperemic flow stimulus (endothelium-dependent) and sub-lingual nitroglycerine (NTG; endothelium-independent); b) exhaled and plasma/urine total NO2/NO3 using chemiluminescence (Sievers 280NOA) with either KI or VCl3 in HCl as the reductants; c) blood pressure. Additionally, we measured multiple regulators of vascular tone and injury. Comparisons were analyzed using Spearman signed rank tests. Results: Of 25 pts (16 F, 9 M) treated, 21 patients were fully evaluable. Significant changes or strong trends were observed upon comparing preRx vs. onRx for BP (SBP +12.4, DBP +5.6, MAP +7.9 mm Hg), and flow-mediated BAR (-2.0%) with no changes in hyperemic flow/shear stimulus or smooth muscle function (BAR NTG), indicating a decrease in brachial artery endothelial responsiveness. Exhaled NO decreased (-0.8% d1vs d28 and -0.6% pre/post infusion day1). Measurement and data analysis of urinary/plasma NO2/NO3, as well as angiogenic markers, are almost complete and will be reported. Conclusions: After one month of treatment, BV increased BP and decreased endothelium- dependent BAR and exhaled NO, suggesting potentially broad, mechanism-based effects on NO bioavailability in patients.

[Table: see text]

A phase I, open-label study of the safety and pharmacokinetics (PK) of pazopanib (P) and lapatinib (L) administered concurrently

3088

Background: P is a potent tyrosine kinase inhibitor of VEGF-R1, -R2, and R3, PDGF-α/β, and c-Kit. L is a potent inhibitor of ErbB1 and ErbB2 tyrosine kinases. Several lines of evidence support combined inhibition of VEGFR and Erb in the treatment of malignancies. Methods: Patients (pts) with solid tumors received P and L daily. Safety, limited PK, biomarkers, and clinical activity were evaluated. Dose escalation occurred in cohorts of 3–6 pts based on DLT. Results: Thirty-three pts received L/P doses of 750/250 (n=4), 750/500 (n=6), 1000/250 (n=3), 1000/400 (n=2), 1000/500 (n=4), 1250/250 (n=6), 1250/400 (n=5) and 1500/200 (n=3) mg once daily (qd). Preliminary mean plasma P concentrations 24 h after administration (C24) on Day 22 were ∼19 μg/mL and 23 μg/mL after administration of 250 mg and 500 mg, respectively. These values are similar to mean C24 values observed after administration of 800 mg P alone (23.1 μg/mL). Plasma L concentrations at 750 - 1500 mg qd were similar to those observed after monotherapy. The most frequent AE’s were diarrhea (Grade (G)1 n=10, G2 n=2, G3 n=3), fatigue (G1: n=7, G2 n=5, G4 n=1), nausea (G1 n=9, G2 n=2), anorexia (G1 n=8, G2 n=3), vomiting (G1 n=9), hair depigmentation (n=7), rash (G1 n=6, G2 n=1) and abdominal cramps (G1 n=3, G2 n=2, G3 n=1). Prolonged disease stabilization of > 16 wks (median 21.5 wks) occurred in 10 pts (RCC n=3, CRC n=3, GIST n=1, mesothelioma n=1, adenocarcinoma GE junction n=1, aggressive fibromatosis n=1). 3 pts (renal cancer n=2, and giant cell tumor of the bone n=1) demonstrated tumor shrinkage of < 30% (i.e. SD by RECIST). Conclusions: Concurrent administration of pazopanib and lapatinib was generally well tolerated. Coadministration of lapatinib may alter the PK of pazopanib.

[Table: see text]

Upper urinary tract metastases from adenocarcinoma of the colon

An unusual presentation of colorectal metastasis to the upper urinary tract is reported. The metastasis manifested as a filling defect seen during antegrade pyelography. Cytologic evaluation of aspirated material demonstrated metastatic colonic adenocarcinoma. A dilated collecting system may be caused by intraluminal material including tumor and blood clots. Whenever fixed filling defects are encountered, urine cytology should be sent even in the absence of renal parenchymal involvement by tumor. The cytological evaluation may allow for prompt diagnosis and treatment.

Tyrosinase gene mutations in oculocutaneous albinism�1 (OCA1): definition of the phenotype

Oculocutaneous albinism (OCA) is a common human genetic condition resulting from mutations in at least twelve different genes. OCA1 results from mutations of the tyrosinase gene and presents with the life-long absence of melanin pigment after birth (OCA1A) or with the development of minimal-to-moderate amounts of cutaneous and ocular pigment (OCA1B). Other types of OCA have variable amounts of cutaneous and ocular pigment. We hypothesized that white hair at birth indicates OCA1 and tested this in a sample of 120 probands with OCA and white hair at birth. We found that 102 (85%) of the probands had OCA1 with one or two identifiable tyrosinase gene mutations, with 169 (83%) of the 204 OCA1 tyrosinase gene alleles having identifiable mutations and 35 (17%) having no identifiable change in the coding, splice junction, or proximal promoter regions of the gene. The inability to identify the mutation was more common with OCA1B (24/35, 69%) than with OCA1A (11/35, 31%) alleles. Seven probands with no tyrosinase gene mutations were found to have OCA2 with one or two P gene mutations, and in eleven, no mutations were detected in either gene. We conclude that (1) the presence of white hair at birth is a useful clinical tool suggesting OCA1 in a child or adult with OCA, although OCA2 may also have this presentation; (2) the molecular analysis of the tyrosinase and P genes are necessary for precise diagnosis; and (3) the presence of alleles without identifiable mutations of the tyrosinase gene, particularly in OCA1B, suggests that more complex mutation mechanisms of this gene are common in OCA.

MC1R mutations modify the classic phenotype of oculocutaneous albinism type 2 (OCA2)

The heterogeneous group of disorders known as oculocutaneous albinism (OCA) shares cutaneous and ocular hypopigmentation associated with common developmental abnormalities of the eye. Mutations of at least 11 loci produce this phenotype. The majority of affected individuals develop some cutaneous melanin; this is predominantly seen as yellow/blond hair, whereas fewer have brown hair. The OCA phenotype is dependent on the constitutional pigmentation background of the family, with more OCA pigmentation found in families with darker constitutional pigmentation, which indicates that other genes may modify the OCA phenotype. Sequence variation in the melanocortin-1 receptor (MC1R) gene is associated with red hair in the normal population, but red hair is unusual in OCA. We identified eight probands with OCA who had red hair at birth. Mutations in the P gene were responsible for classic phenotype of oculocutaneous albinism type 2 (OCA2) in all eight, and mutations in the MC1R gene were responsible for the red (rather than yellow/blond) hair in the six of eight who continued to have red hair after birth. This is the first demonstration of a gene modifying the OCA phenotype in humans.

Exploring distributive justice in health care

The allocation of resources to providers and the way in which the resources are then prioritised to specific service areas and patients remain the critical ethical decisions which determine the type of health system a community receives. Health care providers will never be given enough resources to satisfy all the demands placed upon them by a community that is becoming increasingly informed and demanding. This paper discusses the matter of justice as it relates to the distribution of health resources. It translates the theoretical constructs of distribution into a practical situation that arose at The Geelong Hospital. It is important to emphasise that the aim of giving the example is not necessarily to provide the right answer but rather to assist in determining what ought to be the questions.

The effects of collagen hydrolysat on symptoms of chronic fibromyalgia and temporomandibular joint pain

Twenty (20) people who had medically diagnosed fibromyalgia for two to 15+ years participated in and completed a 90-day evaluation to determine effects of collagen hydrolysat on symptoms of chronic fibromyalgia, with twelve reporting temporomandibular joint pain. Collagen hydrolysat is a food supplement that is available without prescription, with no known side effects. Participants were evaluated initially and then at 30-, 60-, and 90-day periods. Final results were obtained and comparisons made. The average pain complaint levels decreased significantly in an overall group average, and dramatically with some individuals. It was concluded that patients with fibromyalgia and concurrent temporomandibular joint problems may gain symptomatic improvement in their chronic symptoms by taking collagen hydrolysat.