On Sparse Vector Recovery Performance in Structurally Orthogonal Matrices via LASSO

In this paper, we consider the compressed sensing problem of reconstructing a sparse signal from an undersampled set of noisy linear measurements. The regularized least squares or least absolute shrinkage and selection operator (LASSO) formulation is used for signal estimation. The measurement matrix is assumed to be constructed by concatenating several randomly orthogonal bases, which we refer to as structurally orthogonal matrices. Such measurement matrix is highly relevant to large-scale compressive sensing applications because it facilitates rapid computation and parallel processing. Using the replica method in statistical physics, we derive the mean-squared-error (MSE) formula of reconstruction over the structurally orthogonal matrix in the large-system regime. Extensive numerical experiments are provided to verify the analytical result. We then consider the analytical result to investigate the MSE behaviors of the LASSO over the structurally orthogonal matrix, with an emphasis on performance comparisons with matrices with independent and identically distributed (i.i.d.) Gaussian entries. We find that structurally orthogonal matrices are at least as good as their i.i.d. Gaussian counterparts. Thus, the use of structurally orthogonal matrices is attractive in practical applications

Clinical spectrum of paradoxical deterioration during antituberculosis therapy in non-HIV-infected patients

Paradoxical deterioration during antituberculosis therapy, defined as the clinical or radiological worsening of pre-existing tuberculous lesions or the development of new lesions in a patient who initially improves, remains a diagnostic dilemma. Although different clinical presentations of paradoxical response have been described, a systematic analysis of the entity in non-HIV-infected patients is lacking. Reported here are two cases of paradoxical deterioration in which sequential changes in lymphocyte counts and tuberculin skin test results are emphasized. In addition, 120 episodes of paradoxical response after antituberculosis treatment were reviewed. Of the total 122 episodes, 101 (82.8%) were associated with extrapulmonary tuberculosis. The median time from commencement of treatment to paradoxical deterioration was 60 days. The median time to onset of central nervous system manifestations (63 days) was longer than the time to onset of manifestations at other sites (56 days) (P=0.02). Development of new lesions in anatomical sites other than those observed at initial presentation was observed in 31 (25.4%) episodes. A surge in the lymphocyte count, accompanied by an exaggerated tuberculin skin reaction, was observed in our patients during the paradoxical deterioration, analogous to the findings in HIV-positive patients. Treatment of the paradoxical response included surgical intervention (60.7%) and administration of steroids (39.3%). The use of steroids appeared to be safe in this series, as 95% of the Mycobacterium tuberculosis isolates were susceptible to first-line antituberculosis therapy.postprin

Plasma high sensitivity troponin T levels in adult survivors of childhood leukaemias: determinants and associations with cardiac function

published_or_final_versio

The 23-valent polysaccharide pneumococcal vaccination is not useful in BMT patients at risk of pneumococcal bacteremic sepsis

published_or_final_versio

Significance of Twist expression and its association with E-cadherin in esophageal squamous cell carcinoma

in esophageal squamous cell carcinom

Clinical and neuroradiological features of viral encephalitis: a hospital-based study

Oral PresentationThis journal supplement contains abstracts from the 17th MRC; Dept. of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong KongTopics: Basic science, translational and clinical researchINTRODUCTION: Viral encephalitis is an important infection of the central nervous system with significant morbidity and mortality. We studied the clinical, laboratory and radiological characteristics of viral encephalitis patients managed in our hospital, focusing on factors associated with poor prognosis. METHODS: We retrospectively studied the clinical features of patients diagnosed …published_or_final_versionThe 17th Medical Research Conference (MRC), Department of Medicine, University of Hong Kong, Hong Kong, 14 January 2012. In Hong Kong Medical Journal, 2012, v. 18 suppl. 1, p. 31, abstract no. 3

Health- and oral health-related quality of life among preschool children with cerebral palsy

Objectives: To assess the health- and oral health-related quality of life of preschool children with cerebral palsy (CP) and to determine their inter-relationship between the two quality of life measures. Methods: A total of 144 preschool children with and without CP were invited to participate in the case-control study. Health-related quality of life was assessed by the Pediatric Quality of Life Inventory Version 4.0 (PedsQL™ 4.0) and oral health-related quality of life by the Early Childhood Oral Health Impact Scale (ECOHIS). Differences in PedsQL™ 4.0 and ECOHIS scores were determined between the groups, and correlation between PedsQL and ECOHIS were explored. Results: Significant differences in overall scores of PedsQL™ 4.0 (P < 0.001) and in overall scores of ECOHIS (P < 0.05) were apparent between the two groups. In terms of health- and oral health-related quality of life, preschool children with CP fared worse than the age-gender-matched control group. There was a positive albeit weak correlation (r = 0.203, P < 0.05) between PedsQL™ 4.0 and ECOHIS scores. Conclusions: Differences in health- and oral health-related quality of life exist among preschool children with CP. Correlation between health- and oral health-related quality of life could at best be described as weak. © 2010 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201

A Garlic Derivative, S-allylcysteine (SAC), Suppresses Proliferation and Metastasis of Hepatocellular Carcinoma

Background: Hepatocellular carcinoma (HCC) is highly malignant and metastatic. Currently, there is no effective chemotherapy for patients with advanced HCC leading to an urgent need to seek for novel therapeutic options. We aimed to investigate the effect of a garlic derivative, S-allylcysteine (SAC), on the proliferation and metastasis of HCC. Methodology/Principal Findings: A series of in vitro experiments including MTT, colony-forming, wound-healing, invasion, apoptosis and cell cycle assays were performed to examine the anti-proliferative and anti-metastatic effects of SAC on a metastatic HCC cell line MHCC97L. The therapeutic values of SAC single and combined with cisplatin treatments were examined in an in vivo orthotopic xenograft liver tumor model. The result showed that the proliferation rate and colony-forming abilities of MHCC97L cells were suppressed by SAC together with significant suppression of the expressions of proliferation markers, Ki-67 and proliferating cell nuclear antigen (PCNA). Moreover, SAC hindered the migration and invasion of MHCC97L cells corresponding with up-regulation of E-cadherin and down-regulation of VEGF. Furthermore, SAC significantly induced apoptosis and necrosis of MHCC97L cells through suppressing Bcl-xL and Bcl-2 as well as activating caspase-3 and caspase-9. In addition, SAC could significantly induce the S phase arrest of MHCC97L cells together with down-regulation of cdc25c, cdc2 and cyclin B1. In vivo xenograft liver tumor model demonstrated that SAC single or combined with cisplatin treatment inhibited the progression and metastasis of HCC tumor. Conclusions/Significance: Our data demonstrate the anti-proliferative and anti-metastatic effects of SAC on HCC cells and suggest that SAC may be a potential therapeutic agent for the treatment of HCC patients. © 2012 Ng et al.published_or_final_versio