Urbanization in Sha Tin and Tuen Mun : problems and coping strategies

This paper examines the urbanization experiences in two communities of Hong Kong, namely, Sha Tin and Tuen Mun. Owing to the comparative locations and infrastructure concerned, the development of Sha Tin is much faster and more effective than that of Tuen Mun. In this paper, governmental new town development planning, resident population change, internal migration, class and family composition, labour force participation as well as the pull-push factors in implementation of housing policies and in shifting of supporting networks will be discussed

Interfacial bonding in a nanoclay/polymer composite

In this study, X-ray photoelectron spectroscopy (XPS) was conducted to analyze the chemical composition between epoxy matrix and nanocomposite. This experiment revealed that a chemical bonding at an interface between the matrix and nanoclay of the composites did exist. Thus, such bonding can enhance the mechanical and thermal properties of resultant polymer composites as reported in many literatures

Ad hoc influenza vaccination during years of significant antigenic drift in a tropical city with 2 seasonal peaks

We evaluated the acceptability of an additional ad hoc influenza vaccination among the health care professionals following seasons with significant antigenic drift. Self-administered, anonymous surveys were performed by hard copy questionnaires in public hospitals, and by an on-line platform available to all healthcare professionals, from April 1st to May 31st, 2015. A total of 1290 healthcare professionals completed the questionnaires, including doctors, nurses, and allied health professionals working in both the public and private systems. Only 31.8% of participating respondents expressed an intention to receive the additional vaccine, despite that the majority of them agreed or strongly agreed that it would bring benefit to the community (88.9%), save lives (86.7%), reduce medical expenses (76.3%), satisfy public expectation (82.8%), and increase awareness of vaccination (86.1%). However, a significant proportion expressed concern that the vaccine could disturb the normal immunization schedule (45.5%); felt uncertain what to do in the next vaccination round (66.0%); perceived that the summer peak might not occur (48.2%); and believed that the summer peak might not be of the same virus (83.5%). Furthermore, 27.8% of all respondents expected that the additional vaccination could weaken the efficacy of previous vaccinations; 51.3% was concerned about side effects; and 61.3% estimated that there would be a low uptake rate. If the supply of vaccine was limited, higher priority groups were considered to include the elderly aged ≥65 years with chronic medical conditions (89.2%), the elderly living in residential care homes (87.4%), and long-stay residents of institutions for the disabled (80.7%). The strongest factors associated with accepting the additional vaccine included immunization with influenza vaccines in the past 3 years, higher perceived risk of contracting influenza, and higher perceived severity of the disease impact. The acceptability to an additional ad hoc influenza vaccination was low among healthcare professionals. This could have a negative impact on such additional vaccination campaigns since healthcare professionals are a key driver for vaccine acceptance. The discordance in perceived risk and acceptance of vaccination regarding self versus public deserves further evaluation

Laboratory Diagnosis of SARS

The virologic test results of 415 patients with severe acute respiratory syndrome (SARS) were examined. The peak detection rate for SARS-associated coronavirus occurred at week 2 after illness onset for respiratory specimens, at weeks 2 to 3 for stool or rectal swab specimens, and at week 4 for urine specimens. The latest stool sample that was positive by reverse transcription–polymerase chain reaction (RT-PCR) was collected on day 75 while the patient was receiving intensive care. Tracheal aspirate and stool samples had a higher diagnostic yield (RT-PCR average positive rate for first 2 weeks: 66.7% and 56.5%, respectively). Pooled throat and nasal swabs, rectal swab, nasal swab, throat swab, and nasopharyngeal aspirate specimens provided a moderate yield (29.7%–40.0%), whereas throat washing and urine specimens showed a lower yield (17.3% and 4.5%). The collection procedures for stool and pooled nasal and throat swab specimens were the least likely to transmit infection, and the combination gave the highest yield for coronavirus detection by RT-PCR. Positive virologic test results in patient groups were associated with mechanical ventilation or death (p < 0.001), suggesting a correlation between viral load and disease severity

Acupuncture mobilizes the brain's default mode and its anti-correlated network in healthy subjects

Previous work has shown that acupuncture stimulation evokes deactivation of a limbic-paralimbic-neocortical network (LPNN) as well as activation of somatosensory brain regions. This study explores the activity and functional connectivity of these regions during acupuncture vs. tactile stimulation and vs. acupuncture associated with inadvertent sharp pain. Acupuncture during 201 scans and tactile stimulation during 74 scans for comparison at acupoints LI4, ST36 and LV3 was monitored with fMRI and psychophysical response in 48 healthy subjects. Clusters of deactivated regions in the medial prefrontal, medial parietal and medial temporal lobes as well as activated regions in the sensorimotor and a few paralimbic structures can be identified during acupuncture by general linear model analysis and seed-based cross correlation analysis. Importantly, these clusters showed virtual identity with the default mode network and the anti-correlated task-positive network in response to stimulation. In addition, the amygdala and hypothalamus, structures not routinely reported in the default mode literature, were frequently involved in acupuncture. When acupuncture induced sharp pain, the deactivation was attenuated or became activated instead. Tactile stimulation induced greater activation of the somatosensory regions but less extensive deactivation of the LPNN. These results indicate that the deactivation of the LPNN during acupuncture cannot be completely explained by the demand of attention that is commonly proposed in the default mode literature. Our results suggest that acupuncture mobilizes the anti-correlated functional networks of the brain to mediate its actions, and that the effect is dependent on the psychophysical response

Orienting Attention Modulates Pain Perception: An ERP Study

2011-2012 > Academic research: refereed > Publication in refereed journalpublished_fina

Humanization, expression and characterization of an anti-hepatocellular carcinoma monoclonal antibody

Hepatocellular carcinoma (HCC) is a common cancer affecting majority of the Chinese. Due to the problem of non-specificity, common methods of cancer treatment including systemic chemotherapy, affects not only cancer cells but also normal tissues. In order to develop a specific treatment for HCC, a murine anti-human HCC monoclonal antibody was raised in 1991. However, murine monoclonal antibodies will cause HAMA (Human Anti-Murine Antibody) reaction when injected into human body, hence they are not ideal for use in human cancer therapy. One way to prevent the HAMA reaction is to "umanize" the murine monoclonal antibody before clinical application. The aim of humanization is to reduce the murine monoclonal antibody's immunogenicity while maintaining its binding activity. Human consensus sequence was used as a template to design the amino acid sequence of the humanized antibody variable region, and synthetic DNA molecules for protein expression were produced through overlapping PCR from single strand oligonucleotides. The synthetic DNA molecules and human antibody constant region cDNA were used to construct two human cytomegalovirus promotor-based expression vectors for both antibody light chain and heavy chain. Completely assembled humanized antibody was expressed in mammalian cells and purified using protein A. The humanized antibody has been found to have binding activity to a human liver cancer cell-line (SMMC-7721)

Investigations of p53 mutations and effects on drug resistance

In liver cancer, aflatoxin B1 is a potent carcinogen and drug resistance is a major obstruction in chemotherapy. Certain p53 mutations may enhance drug resistance in cancer cells. This study examined aflatoxin B1-induced p53 mutations and the impact of cytosine methylation in this process and investigated whether two common p53 mutants (R248Q and R273C) in liver cancer would increase drug resistance. The p53 template was treated with aflatoxin B1 in vitro. Cytosine methylation enhances mutation at CpG sites, but no mutation at the aflatoxin B1 related hot spot at codon 249 was detected in vitro. Stable cell lines expressing the two p53 mutants (R248Q and R273C) were established by transfecting the p53-null Hep3B cells with mutant p53 expression vectors and the effect of the anti-cancer drugs, doxorubicin and taxol on the p53 mutant expressing cells were examined. The cells expressing the p53 mutant, R248Q, but not R273C, displayed cross-resistance to both drugs. Moreover, both the expression and the activity of the multiple drug resistance gene product, P-glycoprotein, were elevated in the p53 mutant R248Q expressing cells. Reduced uptake of doxorubicin was also observed in the R248Q expressing cells. These results suggest that expression of the p53 mutant, R248Q, in the liver cancer cells may enhance their drug resistance and that up-regulation of the P-glycoprotein activity may contribute to this protective effect