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Biomedical subjects

Sian Griffiths

Publications and source records attributed to Sian Griffiths.

8 recordsLinked to original sources
PubMed2006

Perceptions about status and modes of H5N1 transmission and associations with immediate behavioral responses in the Hong Kong general population.

OBJECTIVES: Perceptions and associated behavioral responses to H5N1 avian influenza were investigated. METHODS: A random telephone survey interviewed 805 Hong Kong adults in November 2005. RESULTS: Of respondents, 37.9% believed that bird-to-human transmission had occurred somewhere in the last year (Hong Kong: 17.3%). Similar figures for human-to-human transmission were 16.8% (some locale) and 6.8% (Hong Kong). Many perceived bird-to-human H5N1 are transmittable via long-distance airborne transmission (35.8%), contaminated water sources (44%) and insect bites (48%). Corresponding figures for human-to-human H5N1 transmission were 47.9%, 47.3% and 48.9% respectively. In the last 3 months, 49.4% of the respondents exhibited one of the 4 studied behavioral responses; the variable was associated with unconfirmed beliefs that past-year human-to-human H5N1 transmission had occurred in Hong Kong (adjusted OR=2.08). Beliefs that human-to-human transmission had occurred somewhere were associated with the 4 individual behaviors studied (adjusted OR=1.58-4.24). Perceptions that human-to-human H5N1 should be transmittable via contaminated water sources was associated with avoidance of visiting hospitals and eating less poultry (adjusted OR=1.69 and 1.64). Belief about airborne transmission of human-to-human H5N1 was associated with perceived stress (adjusted OR=2.32). CONCLUSIONS: Widespread unconfirmed beliefs about status of HN51 epidemic are associated with the general public's behavioral responses. Timely dissemination of up-to-date information is greatly warranted.

Adult↗
PubMed2006

Alcohol use among entrants to a Hong Kong University.

AIM: This study of first year entrants to one of the major universities in Hong Kong describes the pattern of their alcohol consumption, their binge drinking, alcohol abuse, and dependence. METHODS: A retrospective cross-sectional study was conducted. A representative sample of year 1 students 2630/2968 (89%) newly admitted to the Chinese University of Hong Kong in 2003 were recruited to participate in a structured self-administered questionnaire. RESULTS: First year university students in Hong Kong have low rates of ever drinking alcohol (62%), and the rates of binge drinking and alcohol-related problems were 7 and 0.8%, respectively. The pattern of binge drinking is more common than weekly drinking (2.3%). Binge drinkers are more likely to have experienced alcohol-related interpersonal problems or (95% CI) = 6.5 (1.7-24.5). Males were more likely to drink, to binge drink, and to drink frequently. CONCLUSIONS: In contrast with students in the west, the majority of first year university students in Hong Kong are not binge or regular drinkers. However, there is a subgroup who smoke, drink more, and use alcohol as a means of coping with stress. This group may be particularly in need of a brief intervention, such as providing counseling and referral services.

Adolescent↗
PubMed2006

The heterogeneous nature of germline mutations in NF1 patients with malignant peripheral serve sheath tumours (MPNSTs).

Malignant peripheral nerve sheath tumours (MPNSTs) are a major cause of mortality in patients with neurofibromatosis 1 (NF1). We have analysed lymphocyte DNA samples from 30 NF1 patients with MPNSTs to determine their underlying constitutional NF1 gene mutations. Mutations were detected in 27/30 (90%) of these patients. NF1 mutations identified included nonsense, missense, frameshift, splice site mutation and single or multi-exonic deletions and with no obvious clustering of the mutations across the gene. Fourteen of the mutations represent novel gene changes. There did not appear to be any relationship between the mutation type and the level of clinical severity observed. Of the 20 patients with high grade MPNSTs, seven patients had small (<20 bp) and multi-exonic deletions and three had small insertions (<20 bp). Several studies have suggested that NF1 patients with a constitutional 1.5 Mb deletion of the NF1 gene have an increased risk of developing malignant peripheral nerve sheath tumours (MPNSTs). None of our patients had a 1.5 Mb deletion. Larger prospective studies are needed to ascertain whether there is a different spectrum of NF1 mutations in NF1 patients with high grade compared to low grade MPNSTs and of patients with the 1.5Mb deletion, in order to determine the true frequency of MPNST in this sub-group of NF1 patients.

Adolescent↗
PubMed2004

Characterization of the somatic mutational spectrum of the neurofibromatosis type 1 (NF1) gene in neurofibromatosis patients with benign and malignant tumors.

One of the main features of neurofibromatosis type 1 (NF1) is benign neurofibromas, 10-20% of which become transformed into malignant peripheral nerve sheath tumors (MPNSTs). The molecular basis of NF1 tumorigenesis is, however, still unclear. Ninety-one tumors from 31 NF1 patients were screened for gross changes in the NF1 gene using microsatellite/restriction fragment length polymorphism (RFLP) markers; loss of heterozygosity (LOH) was found in 17 out of 91 (19%) tumors (including two out of seven MPNSTs). Denaturing high performance liquid chromatography (DHPLC) was then used to screen 43 LOH-negative and 10 LOH-positive tumors for NF1 microlesions at both RNA and DNA levels. Thirteen germline and 12 somatic mutations were identified, of which three germline (IVS7-2A>G, 3731delT, 6117delG) and eight somatic (1888delG, 4374-4375delCC, R2129S, 2088delG, 2341del18, IVS27b-5C>T, 4083insT, Q519P) were novel. A mosaic mutation (R2429X) was also identified in a neurofibroma by DHPLC analysis and cloning/sequencing. The observed somatic and germline mutational spectra were similar in terms of mutation type, relative frequency of occurrence, and putative underlying mechanisms of mutagenesis. Tumors lacking mutations were screened for NF1 gene promoter hypermethylation but none were found. Microsatellite instability (MSI) analysis revealed MSI in five out of 11 MPNSTs as compared to none out of 70 neurofibromas (p=1.8 x 10(-5)). The screening of seven MPNSTs for subtle mutations in the CDKN2A and TP53 genes proved negative, although the screening of 11 MPNSTs detected LOH involving either the TP53 or the CDKN2A gene in a total of four tumors. These findings are consistent with the view that NF1 tumorigenesis is a complex multistep process involving a variety of different types of genetic defect at multiple loci.

Alleles↗