Focal fatty change: a rare hepatic manifestation of diabetes mellitus

Focal fatty change of the liver is a rare and poorly recognised entity. Most of the previously reported cases occurred in patients suffering from the usual steatogenic conditions, such as diabetes mellitus and obesity. The focality of the lesion, however, remains unexplained. The author reports a rare case of subcapsular focal fatty change of the liver occurring in a 60-year-old Chinese woman suffering from poorly controlled adult-onset diabetes mellitus. The underlying pathogenesis for the focal fatty change is thought to be related to local ischaemic effect secondary to diabetic angiopathy, which may further enhance the steatogenicity of diabetes mellitus. The recognition of focal fatty change of the liver is important in order to avoid misdiagnosis of other space-occupying lesions radiologically and macroscopically.published_or_final_versio

Langerhans' cell histiocytosis: Possible association with malignant germ cell tumour

A rare case of adult onset Langerhans' cell histiocytosis associated with dysgerminoma in a 35 year old Chinese woman is reported. The patient had a history of dysgerminoma of left ovary 15 years previously and had undergone surgery followed by radiotherapy and an uneventful recovery. She presented again in March 1994, this time with a left clavicular mass, which was shown histologically to be Langerhans' cell histiocytosis. The report illustrates the probable association between the two lesions, with some discussion on the underlying pathogenesis.published_or_final_versio

A community study on the relationship of stress and periodontitis

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Oral health-related quality of life and periodontal status

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A community study on the relationship of dental anxiety with oral health status and oral health-related quality of life

Objective: To investigate the relationship of dental anxiety with oral health status and oral health-related quality of life (OHQoL) among dentate subjects living in Hong Kong. Methods: One thousand Hong Kong residents who were aged 25-64 years and predominantly Chinese were asked to complete the Chinese short-forms of the Dental Anxiety Inventory (SDAxI) and Oral Health Impact Profile (OHIP-14S). Dental (DMFT index) and periodontal statuses [full-mouth clinical attachment level (CAL)] were also assessed. Results: Ninety-six (9.6%; mean SDAxI, 9.6), 799 (79.9%; mean SDAxI, 15.0), and 105 (10.5%; mean SDAxI, 27.4) participants had low, average, and high dental anxiety, respectively. The mean DMFT/CAL scores of each SDAxI subgroup were 8.5/1.4, 9.3/1.9, and 9.8/3.6, respectively. The corresponding mean OHIP-14S scores for each SDAxI subgroup were 4.0, 8.1, and 13.2, respectively. Post hoc analysis, adjusted for possible confounding factors, revealed statistically significant differences in DMFT and CAL scores in subjects with low versus high level of SDAxI, and significant differences in OHIP-14S scores between all 3 SDAxI categories. Conclusion: The trait disposition of dental anxiety may be a significant risk indicator of poor dental and periodontal status and is associated with a worse OHQoL. © 2007 The Authors.postprin

Association between dental anxiety and periodontal attachment loss

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A community study on the relationship between stress, coping, affective dispositions and periodontal attachment loss

Background: Psychological factors may increase the risk for periodontal diseases. Contemporary conceptualization of the stress process supports the evaluation of stress at three levels: stressors, moderating and mediating factors, and stress reactions. Objective: This study was undertaken to investigate the relationship of periodontal disease in terms of clinical attachment level (CAL) to psychosocial stress, making reference to the major components of stress process. Methods: A cross-sectional study of 1000 subjects aged 25-64 years in Hong Kong was conducted. Subjects were asked to complete a set of questionnaires measuring stressors including changes, significant life event and daily strains, stress reactions including physiological and affective responses, and coping and affective dispositions. CAL was assessed. Results: Individuals with high mean CAL values had higher scores on the job and financial strain scales than periodontally healthy individuals (P < 0.05), after adjusting for age, gender, cigarette smoking and systemic disease. Depression, anxiety trait, depression trait, problem-focused coping, and emotion-focused coping were also related to CAL. Logistic regression analysis indicated that all these factors were significant risk indicators for periodontal attachment loss, except problem-focused coping, which reduced the odds of CAL. Individuals who were high emotion-focused copers, low problem-focused copers, trait anxious, or trait depressive had a higher odds of more severe CAL. Conclusion: Chronic job and financial strains, depression, inadequate coping, and maladaptive trait dispositions are significant risk indicators for periodontal attachment loss. Adequate coping and adaptive trait dispositions, evidenced as high problem-focused coping and low anxiety/ depression trait, may reduce the stress-associated odds. © Blackwell Munksgaard, 2006.postprin

Synthesis and photophysical properties of some conjugated polymers functionalized with ruthenium polypyridine complexes

Symposium J: Electrical, Optical and Magnetic Properties of Organic Solid-State Materials IVA series of conjugated polymers functionalized with different ruthenium polypyridine metal complexes were synthesized by the palladium catalyzed reaction. Two conjugated polymer systems have been studied: 1. poly(phenylenevinylene) with bis(2,2':6',2''-terpyridine) ruthenium (II) on the mainchain and 2. quinoxaline based polymers with tris(2,2'-bipyridine) ruthenium (II). The ruthenium polypyridine complexes exhibit a long-lived metal to ligand charge transfer excited state which can enhance the photosensitivity of the resulting polymers. Different physical properties such as the photoconductivity and charge mobility in these polymers are also studied.published_or_final_versio

Block diagonal and schur complement preconditioners for block-toeplitz systems with small size blocks

In this paper we consider the solution of Hermitian positive definite block-Toeplitz systems with small size blocks. We propose and study block diagonal and Schur complement preconditioners for such block-Toeplitz matrices. We show that for some block-Toeplitz matrices, the spectra of the preconditioned matrices are uniformly bounded except for a fixed number of outliers where this fixed number depends only on the size of the block. Hence, conjugate gradient type methods, when applied to solving these preconditioned block-Toeplitz systems with small size blocks, converge very fast. Recursive computation of such block diagonal and Schur complement preconditioners is considered by using the nice matrix representation of the inverse of a block-Toeplitz matrix. Applications to block-Toeplitz systems arising from least squares filtering problems and queueing networks are presented. Numerical examples are given to demonstrate the effectiveness of the proposed method. © 2007 Society for Industrial and Applied Mathematics.published_or_final_versio

Photoconductivity and charge transporting properties of metal-containing poly(p-phenylenevinylene)s

A novel type of poly(p-phenylenevinylene)s which contain bis(2.2′:6′,2″-terpyridine) ruthenium (II) complexes has been developed. The absorption of the polymers at 500 nm was strongly enhanced by the metal complexes due to the presence of the metal-ligand charge transfer transition. The charge transportation is dispersive with hole carrier mobilities and activation energy of ∼7 × 10-5 cm2 V-1 s-1 and 0.20 eV. respectively, depending on the concentration of the metal complex. A log μ vs E1/2 plot shows that hole mobilities decrease with increasing field, which suggests the presence of off-diagonal disorder in the hopping sites. © 1997 American Institute of Physics.published_or_final_versio