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C Hobbs

Publications and source records attributed to C Hobbs.

At least 19 recordsLinked to original sources
PubMed2005

Bond breaking coupled with translation in rolling of covalently bound molecules.

The response of a C60 molecule to manipulation across a surface displays a long range periodicity which corresponds to a rolling motion. A period of three or four lattice constants is observed and is accompanied by complex subharmonic structure due to molecular hops through a regular, repeating sequence of adsorption states. Combining experimental data and ab initio calculations, we show that this response corresponds to a rolling motion in which two of the four Si-C60 covalent bonds act as a pivot over which the molecule rotates while moving through one lattice constant and identify a sequence of C60 bonding configurations that accounts for the periodic structure.

Journal Article↗
PubMed2005

Subdural haematoma and effusion in infancy: an epidemiological study.

AIM: To determine incidence, aetiology, and clinical features of subdural haematoma and effusion (SDH/E) in infancy throughout the British Isles. METHODS: Cases were notified to the British Paediatric Surveillance Unit over 12 months by paediatricians, neurosurgeons, and paediatric and forensic pathologists. RESULTS: A total of 186 infants (121 boys, 65 girls) aged 0-2 years were identified. Annual incidence of SDH/E for the UK and Republic of Ireland is 12.54/100,000 aged 0-2 (95% CI 10.3 to 14.62) and 24.1/100,000 aged 0-1 (95% CI 20.89 to 28.18). A total of 106 infants suffered non-accidental head injury (NAHI), 7 accidental head injury, 26 a perinatal cause, 7 a non-traumatic medical condition, 23 meningitis, and in 17 the cause was undetermined; 35 infants died. Significant differences were found in injury pattern, body weight, and Townsend score between NAHI and SDH/E from other cause. There were fewer diagnostic investigations in non-NAHI cases. Delay in diagnosis of greater than a week occurred in 48/181. CONCLUSION: SDH/E is a significant cause of morbidity and mortality in infancy. NAHI is the predominant cause of SDH/E. SDH/E can present in a non-specific and varied way and must be considered in any infant who is unwell. Determining the cause of the SDH/E in some cases continues to present a diagnostic challenge.

Child Abuse↗
PubMed2001

Moving out and moving on: some ethnographic observations of deinstitutionalization in an Australian community.

Since the 1950s deinstitutionalization has taken place for people with mental illnesses in the Western world. The growth of community care and residential facilities, as well as planning and implementation of policies, has varied in timing and orientation. An appreciation of the process of change affecting people discharged to the community highlights their strength, resilience, and vulnerabilities. This paper outlines a two and a half year ethnographic qualitative study undertaken in Australia, where 47 long-stay psychiatric inpatients were discharged to the community. The process accompanied the amalgamation of two major psychiatric hospitals, resulting in the closure of one. Findings demonstrated slow but positive change for residents as they reintegrated into the community. A separate quantitative and economic study was undertaken alongside the qualitative study (for results see Hobbs, et al., 2000; Newton, et al, 2000; Lapsley, et al., 2000).

Adult↗
PubMed2000

Ectopic expression of NCAM in skeletal muscle of transgenic mice results in terminal sprouting at the neuromuscular junction and altered structure but not function.

The neuromuscular system provides an excellent model for the analysis of molecular interactions involved in the development and plasticity of synaptic contacts. The neural cell adhesion molecule (NCAM) is believed to be involved in the development and plasticity of the neuromuscular junction, in particular the axonal sprouting response observed in paralyzed and denervated muscle. In order to explore the role of myofiber NCAM in modulating the differentiation of motor neurons, we generated transgenic mice expressing a GPI-anchored NCAM isoform that is normally found in developing and denervated muscle, under the control of a skeletal muscle-specific promoter. This results in the constitutive expression of NCAM at postnatal ages, a time when the endogenous mouse NCAM is absent from the myofiber. We found that a significant number of neuromuscular junctions in adult transgenic animals displayed terminal sprouting (>20%) reminiscent of that elicited in response to cessation of neuromuscular activity. Additionally, a significant increase in the size and complexity of neuromuscular synapses as a result of extensive intraterminal sprouting was detected. Electrophysiological studies, however, revealed no significant alterations of neuromuscular transmission at this highly efficient synapse. Sprouting in response to paralysis or following nerve crush was also significantly enhanced in transgenic animals. These results suggest that in this ectopic expression model NCAM can directly modulate synaptic structure and motor neuron-muscle interactions. The results contrast with knockout experiments of the NCAM gene, where very limited changes in the neuromuscular system were observed.

Acetylcholinesterase↗
PubMed2000

Deinstitutionalisation for long-term mental illness: cost differences in hospital and community care.

OBJECTIVE: This project studied the cost analysis of psychiatric hospital and then community care for long-stay patients with chronic mental illness discharged during the closure of a psychiatric hospital in Sydney. METHOD: Expenditure and income data in both settings were collected. Costs were analysed on an occupied bed-day basis. RESULTS: The hospital setting cost more per patient per day compared with the various community costs which were one-third to one-half of the comparable hospital costs. CONCLUSIONS: The analysis demonstrated overall that hospital care was nearly twice as expensive as care in the community setting. The factors which may have influenced, although not necessarily altered, the substance of the findings largely related to 'organisational efficiency'. The mental hospital as an older, more rigid system was likely to be less efficient than the newer community service provision which was under intensive scrutiny both clinically and financially by all interested parties.

Australia↗
PubMed2000

Deinstitutionalisation for long-term mental illness: an ethnographic study.

OBJECTIVE: Deinstitutionalisation of seriously mentally ill people in the developed world, including Australia, has occurred since the middle of this century. Evaluation of the effects of this change on the lives of individuals is of paramount importance to ensure that policies are acceptable and effective. Increasingly, multifaceted studies are considered essential for comprehensive health research. The qualitative aspect of this study complements the clinical and economic components. METHOD: An ethnographic approach enabled contextual, qualitative data to be gathered from within the social world of 47 hospital residents as they moved to the community. A social anthropologist acting explicitly as a participant observer undertook fieldwork over two and a half years both pre- and post-discharge. Qualitative data were collected, stored and analysed separately from quantitative and economic data. RESULTS: Ethnographic findings generally supported and, in many cases, mirrored clinical results. Of the total cohort of 47 patients transferred to the community, the 40 who continue to live outside of hospital all reported a preference for community living. The importance of freedom and simple liberties cannot be underestimated as factors that enabled this resilient group of people to work creatively through difficult periods. CONCLUSION: Properly planned and resourced deinstitutionalisation not only maintains people with a prolonged mental illness outside of hospital, it also enhances their quality of life. Subjective descriptive material focusing on personal experiences adds meaning to quantitative research data allowing health professionals to more fully understand the implications of health policy on the lives of individuals.

Anthropology↗
PubMed2000

Deinstitutionalisation for long-term mental illness: a 2-year clinical evaluation.

OBJECTIVE: The closure of a long-stay psychiatric hospital in Sydney caused the transfer of an initial 40 very long-term patients to four community residences, each with 10 beds, for a continuing process of deinstitutionalisation. Community psychiatric service support and 24-h supervision were provided. This paper describes the residents' clinical progress which was assessed over a 2-year period. METHOD: This study employed a quasi-experimental longitudinal design. Evaluation commenced prior to discharge and continued for 2 years following community relocation using the Brief Psychiatric Rating Scale, Life Skills Profile, Social Behaviour Scale, Montgomery Asberg Depression Rating Scale and Quality Of Life measures. Readmission, demographic, case history and medication data were also collected. RESULTS: Of the 40 patients initially transferred to the community, seven required long-term readmission to hospital (either prior to or after amalgamation) and one patient died of medical causes. Additional patients transferred from the hospital to the community following the readmissions. Three of these additional patients had achieved a 2-year community tenure during the study period and were included in the clinical evaluation. The 35 residents in total who remained in the community for 2 years, demonstrated a significant improvement in psychotic symptoms, without significant change in the level of neuroleptic medication. Importantly, the 2 years of community living resulted in a significant increase in the residents' life satisfaction. There were no statistically significant changes in residents' living skills, depressive symptoms or social behaviour problems over the 2 years, indicative of the need for supervision and community service support following deinstitutionalisation. Over the 2-year period, some 37% of the residents required temporary readmission. CONCLUSION: This study demonstrates the clinical effectiveness of deinstitutionalisation, when planned within a mental health system with adequate community resources.

Adolescent↗
PubMed1999

Transgenic models of Huntington's disease.

Huntington's disease (HD) is an inherited neurodegenerative disorder caused by a CAG-polyglutamine repeat expansion. A mouse model of this disease has been generated by the introduction of exon 1 of the human HD gene carrying highly expanded CAG repeats into the mouse germ line (R6 lines). Transgenic mice develop a progressive neurological phenotype with a movement disorder and weight loss similar to that in HD. We have previously identified neuronal inclusions in the brains of these mice that have subsequently been established as the pathological hallmark of polyglutamine disease. Inclusions are present before symptoms, which in turn occur long before any selective neuronal cell death can be identified. We have extended the search for inclusions to skeletal muscle, which, like brain, contains terminally differentiated cells. We have conducted an investigation into the skeletal muscle atrophy that occurs in the R6 lines, (i) to provide possible insights into the muscle bulk loss observed in HD patients, and (ii) to conduct a parallel analysis into the consequence of inclusion formation to that being performed in brain. The identification of inclusions in skeletal muscle might be additionally useful in monitoring the ability of drugs to prevent inclusion formation in vivo.

Animals↗
PubMed1999

Formation of polyglutamine inclusions in non-CNS tissue.

Huntington's disease (HD) is one of a class of inherited progressive neurodegenerative disorders that are caused by a CAG/polyglutamine repeat expansion. We have previously generated mice that are transgenic for exon 1 of the HD gene carrying highly expanded CAG repeats which develop a progressive movement disorder and weight loss with similarities to HD. Neuronal inclusions composed of the exon 1 protein and ubiquitin are present in specific brain regions prior to onset of the phenotype, which in turn occurs long before specific neurodegeneration can be detected. In this report we have extended the search for polyglutamine inclusions to non-neuronal tissues. Outside the central nervous system (CNS), inclusions were identified in a variety of post-mitotic cells. This is consistent with a concentration-dependent nucleation and aggregation model of inclusion formation and indicates that brain-specific factors are not necessary for this process. To possibly gain insights into the wasting that is observed in the human disease, we have conducted a detailed analysis of the timing and progression of inclusion formation in skeletal muscle and an investigation into the cause of the severe muscle atrophy that occurs in the mouse model. The formation of inclusions in non-CNS tissues will be particularly useful with respect to in vivo monitoring of pharmaceutical agents selected for their ability to prevent polyglutamine aggregation in vitro, without the requirement that the agent can cross the blood-brain barrier in the first instance.

Animals↗
PubMed1999

Anterior knee pain syndrome. A review of current concepts and controversies.

Anterior knee pain syndrome is a common condition in the military population. Current management is moving away from surgery as the most effective treatment, towards prolonged specific physiotherapy to recondition the extensor mechanism, especially the Vastus Medialis Obliquus (VMO) component of the quadriceps.

Arthralgia↗
PubMed1998

Shaken babies.

Explore the source record for details and available documents.

Battered Child Syndrome↗
PubMed1998

Muscle-specific locus control region activity associated with the human desmin gene.

We describe the reproduction of the full pattern of expression of the muscle-specific desmin gene in transgenic mice using a 240-kb genomic clone spanning the human desmin locus. Analysis of RNA from adult tissues demonstrated that this fragment possesses all the necessary genetic regulatory elements required to provide reproducible, site-of-integration-independent, physiological levels of tissue-specific expression that is directly proportional to transgene copy number in all muscle cell types. In situ hybridization revealed that in marked contrast to murine desmin which is strongly expressed in the myotome of the somites, skeletal muscles, the heart, and smooth muscle of the vasculature by 9.5 days postcoitum, human desmin transgene expression was completely absent from smooth muscles, was very weak and restricted to the atrium and outflow tract within the heart, and was expressed at only 5% of murine desmin mRNA levels within the myotome of the somites. The spatial distribution and levels of human and mouse desmin expression were not coincident until 14.5 days postcoitum. Immunohistochemical analysis of human embryos at comparable stages of development showed that this transgene faithfully reproduces the human and not the mouse developmental expression pattern for this gene in transgenic mice. These results indicate that the 240-kb desmin genomic clone is capable of establishing an independent, chromatin domain in transgenic mice and provides the first definitive data for muscle-specific locus control region activity. In addition, our results demonstrate that the behavior of human transgenes in mice should, whenever possible, be compared to expression patterns for that gene in human embryonic as well as adult tissues.

Animals↗
PubMed1998

The DUTT1 gene, a novel NCAM family member is expressed in developing murine neural tissues and has an unusually broad pattern of expression.

A new member of the NCAM family mapping to 3p12 has been isolated and predicted to be arranged in five immunoglobulin-like domains and three fibronectin-like domains which are particularly homologous to L1. There is a transmembrane domain and a long cytoplasmic region with no detectable homology to other sequences. Although less closely related to DCC, another family member, both share a loop of positively charged amino acids within the first immunoglobulin domain, unique to these two members of this very large gene family. Preliminary studies of expression in mouse embryos support an inferred role in neural development, but the observation of widespread gene expression in adult human tissues indicates that this protein has additional functions to those performed in neural cells.

Amino Acid Sequence↗
PubMed1997

The relationship of Ki67 and involucrin expression in proliferative, pre-neoplastic and neoplastic skin.

In normal skin, proliferation and differentiation are tightly coupled in order to maintain normal architecture in a continually renewing tissue. The temporal and spatial relationships between these two processes in normal, psoriatic, pre-neoplastic and neoplastic skin were investigated by a double immunolabelling technique with Ki67 as a marker of proliferation and involucrin as a marker of terminal differentiation. In normal skin, expression of the two antigens was strictly spatially segregated. In the abnormal, the proportions of cells expressing the antigens were increased with some loss of the spatial segregation, while small numbers of cells showed dual expression suggesting loss of the normal control between proliferation and differentiation. However, the quantitative ratio of proliferation to differentiation in psoriatic and pre-neoplastic skin was similar to the normal; transition to an invasive phenotype, however, was associated with a reversal of this ratio, and this correlated well with the degree of histological differentiation.

Bowen's Disease↗