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Background: Children diagnosed with medulloblastoma (MB) that are refractory to upfront therapy or experience recurrence have very poor prognoses. Reports of phase I and II studies for these children exist, but bear significant treatment related morbidity and mortality. Methods: A retrospective review of children diagnosed with a pediatric MB from 2002-2015 from the McMaster Pediatric Brain Tumour Study Group (PBTSG) captured a number of pediatric recurrent MB. Results: Over the 13-year period, 31 children with a histological diagnosis of MB were treated. At two years, 21 (67.7%) of 31 patients were free of recurrence and 25 (80.6%) survived. Thirteen children had recurrent or treatment refractory MB. mean time to recurrence was 14.6 months. The mean follow-up for survivors of recurrent MB was 4.0 years. In 3 recurrent MB, the disease had significantly progressed and the patients palliated. For the remaining children, therapy offered included surgery, radiation, and chemotherapy agents either in isolation or in varying combinations. Conclusions: Recurrent MB in our cohort carried a poor prognosis despite administration of salvage therapy. Though there is standardization of the upfront treatment exists, we observed great heterogeneity in the treatment of our 13 patients experiencing recurrence. A greater understanding of the biology of recurrent MB has the potential to guide salvage therapy.
Interstellar ices are widely observed in the infrared spectra of regions where stars and
planetary systems form. Photochemical and thermal evolution of these ices is simulated and
studied in our laboratory where the resulting production of complex organic residues is
routinely performed. Observations of their variability with slightly different starting
chemical conditions can be performed by means of infrared spectroscopy. Organic residues
have interesting chemical properties that make them good potential candidates for
prebiotic chemistry. Numerous other analytical methods (GC-MS, HPLC, mass spectrometry,
etc.) can be combined to refine the knowledge of their chemical composition and structure.
We present here some results on the obtained organic residue resulting from subsequent
heating and sublimation of the irradiated ices which show the formation of some
Twin and sibling studies have identified specific cognitive phenotypes that may mediate the association between genes and the clinical symptoms of attention deficit hyperactivity disorder (ADHD). ADHD is also associated with lower IQ scores. We aimed to investigate whether the familial association between measures of cognitive performance and the clinical diagnosis of ADHD is mediated through shared familial influences with IQ.
Multivariate familial models were run on data from 1265 individuals aged 6–18 years, comprising 920 participants from ADHD sibling pairs and 345 control participants. Cognitive assessments included a four-choice reaction time (RT) task, a go/no-go task, a choice–delay task and an IQ assessment. The analyses focused on the cognitive variables of mean RT (MRT), RT variability (RTV), commission errors (CE), omission errors (OE) and choice impulsivity (CI).
Significant familial association (rF) was confirmed between cognitive performance and both ADHD (rF=0.41–0.71) and IQ (rF=−0.25 to −0.49). The association between ADHD and cognitive performance was largely independent (80–87%) of any contribution from etiological factors shared with IQ. The exception was for CI, where 49% of the overlap could be accounted for by the familial variance underlying IQ.
The aetiological factors underlying lower IQ in ADHD seem to be distinct from those between ADHD and RT/error measures. This suggests that lower IQ does not account for the key cognitive impairments observed in ADHD. The results have implications for molecular genetic studies designed to identify genes involved in ADHD.
Oppositional defiant disorder (ODD) is frequently co-occurring with attention deficit hyperactivity disorder (ADHD) in children and adolescents. Because ODD is a precursor of later conduct disorder (CD) and affective disorders, early diagnostic identification is warranted. Furthermore, the predictability of three recently confirmed ODD dimensions (ODD-irritable, ODD-headstrong and ODD-hurtful) may assist clinical decision making.
Receiver-operating characteristic (ROC) analysis was used in order to test the diagnostic accuracy of the Conners' Parent Rating Scale revised (CPRS-R) and the parent version of the Strength and Difficulties Questionnaire (PSDQ) in the prediction of ODD in a transnational sample of 1093 subjects aged 5–17 years from the International Multicentre ADHD Genetics study. In a second step, the prediction of three ODD dimensions by the same parent rating scales was assessed by backward linear regression analyses.
ROC analyses showed adequate diagnostic accuracy of the CPRS-R and the PSDQ in predicting ODD in this ADHD sample. Furthermore, the three-dimensional structure of ODD was confirmed by confirmatory factor analysis and the CPRS-R emotional lability scale significantly predicted the ODD irritable dimension.
The PSDQ and the CPRS-R are both suitable screening instruments in the identification of ODD. The emotional lability scale of the CPRS-R is an adequate predictor of irritability in youth referred for ADHD.
Low slag volumes favour high productivities. In the case of Sidmar, the burden
consists of more than 90 % sinter. The iron content of the sinter has been optimized.
Slag volume is thus reduced and productivity between 65-70 tHM/m2.24h is achieved.
At high pulverized coal injection rates, the residence time of the coke increases
substantially and a higher degree of degradation is to be expected. Therefore, a careful
monitoring of the coke and sinter quality is of prime importance. This paper describes
the coke and sinter quality used in the Sidmar blast furnaces to control permeability
of the furnace with long term PCI rates of 180 kg/tHM and coke rates around 300 kg/tHM.
A global quality index has been defined which is well correlated with the blast furnace
productivity. Sidmar believes that the quality requirements of the burden can directly
be linked with the requested productivity and that good operational practices are
necessary for optimization of that productivity.
The use of DSM-IV based questionnaires in child psychopathology is on the increase. The internal construct validity of a DSM-IV based model of ADHD, CD, ODD, Generalised Anxiety, and Depression was investigated in 11 samples by confirmatory factor analysis. The factorial structure of these syndrome dimensions was supported by the data. However, the model did not meet absolute standards of good model fit. Two sources of error are discussed in detail: multidimensionality of syndrome scales, and the presence of many symptoms that are diagnostically ambiguous with regard to the targeted syndrome dimension. It is argued that measurement precision may be increased by more careful operationalisation of the symptoms in the questionnaire. Additional approaches towards improved conceptualisation of DSM-IV are briefly discussed. A sharper DSM-IV model may improve the accuracy of inferences based on scale scores and provide more precise research findings with regard to relations with variables external to the taxonomy.
Surveys with ISO (Kessler et al 1996), in particular with the CAM (Cesarsky et al 1996) and PHOT (Lemke et al 1996) instruments, will greatly extend our understanding of extra-galactic populations and their cosmological evolution. The main advantages that ISO surveys have over e.g IRAS are increased sensitivity/depth and wavelength coverage. Within the Guaranteed and Open Time programmes there are many field surveys which will efficiently map the limits in these parameters. In this talk I will briefly overview those surveys before concentrating in more detail on one survey in particular, the ISO survey of the Hubble Deep Field (HDF), to illustrate the kind of results that can be expected.
Locomotion is recognized as an important aspect of behaviour and knowledge of the locomotion of broiler chickens is important for their health and welfare (Lewis and Hurnik, 1989). Würbel (1995) suggested that certain behaviours can give an indication of poor welfare and that preference tests may be used to ‘fine tune’ a housing system.
One case each of: (1) low grade thyroid lymphoma; (2) supraclavicular and para-oesophageal metastasis of a uterine adenocarcinoma; and (3) recurrent multinodular goitre have been encountered in very intimate relationship with the neck of a pharyngeal pouch within the tracheo-oesophageal gutter raising the possibility that the two conditions were interrelated. The practical importance of these cases is that a surgeon excising a pouch from the neck ought to be able to resect a thyroid lobe should it prove necessary, and occasionally endoscopic diverticulotomy is the only reasonable option.
This paper offers an account of the contemporary surgical approach to advanced tumours of the external ear based on a series of 11 patients. There were eight squamous, two basal cell carcinomas and one mucoepidermoid tumour. The traditional method of excision was slightly modified by performing microsurgical dissection of the lateral part of the temporal bone rather than chisel osteotomies, and then including it en bloc with the involved soft tissues. The defect was then closed using a scalp or myocutaneous flap and this combination of otological and reconstructive expertise has proved satisfactory. Four patients are alive with no evidence of disease a mean of 4.2 (range 1.0–7.0) years from surgery: two patients who remained free of disease have subsequently died of unrelated conditions 12 and 24 months post-operatively, and in three cases death from recurrent disease occurred a mean of 1.4 (range 0.9–2.1) years after our surgery. There were two postoperative deaths. Based on the actuarial survival of 36 per cent and a successful disease clearance rate of 54 per cent, our conclusion is that the outlook of this condition has not dramatically improved since the original descriptions of the management of this problem first appeared, although intervention remains justifiable because of the potential curability and relief of symptoms.
A new technique for the treatment of severe epistaxis associated with hereditary haemorrhagic telangiectasia is described. The nasal septum and inferior turbinates, surgically denuded of respiratory epithelium, were grafted using autografts of cultured epithelial sheets derived from buccal epithelium. All patients upon whom this technique has been used have shown considerable lessening in the frequency and severity of their epistaxes although two patients received grafts on two occasions, in each case approximately three months apart. It is postulated that a nasal lining of stratified squamous epithelium is likely to be more resistant to trauma than the normal respiratory type, and this is supported by the observation that bleeds very seldom occur from the oral cavity in this syndrome.
Autologous cultured epithelial layers were established from biopsies from the mucosa of the cheek, a nonkeratinizing region of the oral cavity. These were grafted to the unepithelialized mastoid cavities of nine patients with chronic mastoiditis and severe otorrhoea varying from two to 30 years' duration. All procedures were performed on an out-patient basis, with no anaesthesia except for topical anaesthesia for the mucosal biopsy. In seven of the patients the grafts took well, with complete resolution of the otorrhoea for a minimum follow-up period of eight months. In one patient there was a partial take of the graft with substantial improvement in the rate of discharge. The mastoid cavities of two patients were biopsied five months after grafting, and demonstrated a stratified squamous epithelium, with keratinization of the epithelium clearly evident.
A Retrospective review of 45 patients with advanced squamous cell carcinoma of the head and neck treated by a combination of initial chemotherapy (Price and Hill Schedule A) followed by radiotherapy is presented. The regime produced excellent immediate palliation with a tumour control of 50 per cent, and a disease-free survival of 33 per cent at one year and 27 per cent at two years. Treatment morbidity was minimal in an aged patient group.
A Tertiary dolerite plug at Carneal, Co. Antrim has been contaminated by Chalk with the production of calc-silicates and related minerals. In a larnite-spinel-rock the spinel is of the unusual ferrian variety. It has the composition The spinel, which is brown, has: n, 1·862; D, 3·97; a, 8·1905 Å. A chemical analysis and powder data are given, the implications of experimental data are briefly discussed, and the nomenclature is reviewed.