Next-generation sequence analysis of cancer xenograft models.

Next-generation sequencing (NGS) studies in cancer are limited by the amount, quality and purity of tissue samples. In this situation, primary xenografts have proven useful preclinical models. However, the presence of mouse-derived stromal cells represents a technical challenge to their use in NGS studies.

A crucial requirement for Hedgehog signaling in small cell lung cancer.

Small-cell lung cancer (SCLC) is an aggressive neuroendocrine subtype of lung cancer for which there is no effective treatment. Using a mouse model in which deletion of Rb1 and Trp53 in the lung epithelium of adult mice induces SCLC, we found that the Hedgehog signaling pathway is activated in SCLC cells independently of the lung microenvironment. Constitutive activation of the Hedgehog signaling molecule Smoothened (Smo) promoted the clonogenicity of human SCLC in vitro and the initiation and progression of mouse SCLC in vivo.

A structural model of the dimensions of teacher stress.

A comprehensive survey of teacher stress, job satisfaction and career commitment among 710 full-time primary school teachers was undertaken by Borg, Riding & Falzon (1991) in the Mediterranean islands of Malta and Gozo. A principal components analysis of a 20-item sources of teacher stress inventory had suggested four distinct dimensions which were labelled: Pupil Misbehaviour, Time/Resource Difficulties, Professional Recognition Needs, and Poor Relationships, respectively. To check on the validity of the Borg et al.

A factor analytic study of teachers' perception of pupils' undesirable behaviours: a rejoinder to Langfeldt (1992).

This study investigates the effects of teacher sex and pupil sex in the teachers' perception of the seriousness of three extracted patterns of pupils' undesirable behaviours. In contraposition to Langfeldt's (1992) conclusion that gender differences are no longer observable when investigating complex patterns of behaviour as opposed to single behavioural items the present writers argue that where gender is a true effect this will also be evident at a factorial level of abstraction. A sample of 844 primary school teachers in Malta rated the seriousness of 16 selected undesirable behaviours when these are manifest in boy pupils and in girl pupils.

Teacher's perception of primary schoolchildren's undesirable behaviors: the effect of teaching experience, pupil's age, sex and ability stream.

Using a self-administered questionnaire, the attitudes of 844 Maltese primary school teachers towards 16 selected undesirable behaviours were surveyed. Results indicated that pupils' age is a significant moderator of half of the behaviours; these are perceived to be significantly more serious by teachers in the second three years of the primary school than by their colleagues in the first three years. Significant boy-girl differences in the seriousness of behaviour were revealed in most of the behaviours as rated by teachers in both the first and in the second years.