Detection of enteroviruses during a 2018 hand, foot and mouth disease outbreak in Malaysia

Hand, foot, and mouth disease (HFMD) is a common childhood disease caused by enteroviruses. In 2018, a HFMD outbreak in Malaysia affected over 76,000 children. In this study, we used RT-qPCR and CODEHOP PCR to detect the causative agents in 89 clinically diagnosed HFMD patients in Kuala Lumpur and Selangor. Most (62.9%) of the children were below 3 years old. PCR with either assay detected enteroviruses in 84.2% (75/89) and CODEHOP PCR successfully typed 66.7% (50/75) of the enteroviruses. Sequencing of CODEHOP amplicons showed co-circulation of multiple enteroviruses with coxsackievirus A6 (CV-A6) and A16 as the predominant serotypes, but not the neurovirulent enterovirus A71. CV-A6 infection was more common in children less than 12 months old (p=0.01) and was more likely to cause vesicles in the gluteal area (p=0.01) compared to other enteroviruses. Establishing a robust identification method during HFMD outbreaks is important for patient management and public health responses.

Vertically aligned boron nitride nanosheets: chemical vapor synthesis, ultraviolet light emission, and superhydrophobicity

Boron nitride (BN) is a promising semiconductor with a wide band gap ( approximately 6 eV). Here, we report the synthesis of vertically aligned BN nanosheets (BNNSs) on silicon substrates by microwave plasma chemical vapor deposition from a gas mixture of BF(3)-N(2)-H(2). The size, shape, thickness, density, and alignment of the BNNSs were well-controlled by appropriately changing the growth conditions. With changing the gas flow rates of BF(3) and H(2) as well as their ratio, the BNNSs evolve from three-dimensional with branches to two-dimensional with smooth surface and their thickness changes from 20 to below 5 nm. The growth of the BNNSs rather than uniform granular films is attributed to the particular chemical properties of the gas system, mainly the strong etching effect of fluorine. The alignment of the BNNSs is possibly induced by the electrical field generated in plasma sheath. Strong UV light emission with a broad band ranging from 200 to 400 nm and superhydrophobicity with contact angles over 150 degrees were obtained for the vertically aligned BNNSs. The present BNNSs possess the properties complementary to carbon nanosheets such as intrinsically semiconducting, high temperature stability, and high chemical inertness and may find applications in ultraviolet nanoelectronics, catalyst supports, electron field emission, and self-cleaning coatings, etc., especially those working at high temperature and in harsh environments.

The fabrication of cubic boron nitride nanocone and nanopillar arrays via reactive ion etching

High-density (2 x 10(9) cm(-2)) uniform arrays of cubic boron nitride (cBN) nanocones and nanopillars with a high aspect ratio were fabricated by employing sequential growth and bias-assisted reactive ion etching using gold nano-dots as an etching mask. The mechanism of formation of the nanopillar and nanocone morphologies was discussed in terms of the relative action of ion bombardment etching and chemical etching due to activated hydrogen plasma constituents. The presented method enabled nanostructuring of cBN surfaces over large areas with great uniformity and reproducibility with a controlled aspect ratio. The unique morphology of the nanostructures offers diverse application opportunities in microelectromechanical devices.

Isolation and identification of thiohomosildenafil and thiosildenafil in health supplements

Two unknown compounds are detected and isolated from health supplements for the enhancement of sexual function. The structures of the unknown compounds are elucidated using high-resolution MS, ESI-MS/MS, NMR, UV and IR. One compound is identified as an analogue of sildenafil in which the oxygen atom is substituted with a sulfur atom in the pyrazolopyrimidine moiety, and an ethyl group instead of a methyl group is attached to the piperazinyl nitrogen. Hence, this compound is named thiohomosildenafil. Another compound is also a sildenafil analogue in which the oxygen atom is substituted with a sulfur atom in the pyrazolopyrimidine moiety. This compound is named thiosildenafil. Both the two compounds are first detected in health supplements. The UV, IR and completely assigned NMR data of thiohomosildenafil and thiosildenafil are first reported.

The potential clinical applications of insulin-like growth factor-1 ligand in human breast cancer

Insulin-like growth factor-1 (IGF-1) has become recognized as a growth factor with pro-mitogenic and antiapoptotic effects on a variety of human cells. This article reviews the potential role of IGF-1 ligand in the clinical management of breast cancer patients. Many studies have shown that IGF-1 acts synergistically with oestrogen to stimulate breast cancer cells. Case-control studies have also demonstrated that premenopausal women with high levels of serum IGF-1 have an increased risk of developing breast cancer later in life. Serum IGF-1 levels can therefore be used as a potential biomarker for predicting breast cancer risk. Furthermore, there is evidence that serum IGF-1 levels can serve as a response biomarker in chemoprevention drug trials. The role of IGF-1 expression in breast cancer tissue as a prognostic marker is not clearly established. Identifying the IGF-1 gene polymorphism can potentially be used in predicting breast cancer risk.

Screening of concurrent alpha-thalassaemia 1 in beta-thalassaemia carriers

Thalassaemia is an inherited blood disorder and is a significant public health problem in Malaysia, with many not knowing they carry the gene for thalassaemia. The two major forms are alpha and beta thalassaemia. An individual can co-inherit both the alpha and beta thalassaemia genes. This study determined the frequency of concurrent carriers of alpha thalassaemia in 231 beta thalassaemia carriers. Gap-PCR was done on extracted DNA of the beta thalassaemia samples to check for alpha thalassaemia 1 molecular defect. Eight (3.5%) samples were found to have concurrently inherited the alpha thalassaemia 1 (- -SEA) deletion. The significant carrier rate for alpha thalassaemia 1 indicates the need for the implementation of DNA analysis to complement thalassaemia screening in high risk populations.

Insulin-like growth factor 1 (IGF-1) and its receptor mRNA levels in breast cancer and adjacent non-neoplastic tissue

Previous studies investigating the insulin-like growth factor 1 receptor (IGF-1R) expression in breast cancer tissue and adjacent non-neoplastic breast tissue (ANCT) have produced conflicting results. The IGF-1 and IGF-1R expression in pairs of breast cancer tissue and ANCT were investigated using RT-PCR and immunohistochemistry. The results of both methods were compared.

MATERIALS AND METHODS

IGF-1 and IGF-1R mRNA from 31 specimen pairs were estimated using RT-PCR. Immunohistochemistry for IGF-1R was carried out on 20 specimen pairs and the strength of staining was scored.

RESULTS

The mean relative IGF-1 mRNA level was lower in the cancerous tissue (mean 0.450 +/- 0.206) than in the ANCT (mean 0.632 +/- 0.384) (paired t-test, p = 0.001). There was no measurable difference in relative IGF-1R mRNA levels in the cancerous tissue (mean 0.146 +/- 0.08) and the ANCT (mean 0.14608 +/- 0.108) (paired t-test, p = 0.807). Using immunohistochemistry, there was no statistical difference (paired t-test, p = 0.910) in IGF-1R staining scores between cancer (mean 1.93) and ANCT (mean 1.90). The comparison between the two methodologies showed no correlation (Pearson's Correlation Coefficient = -0.393).

DISCUSSION

It can be concluded that IGF-1 expression is lower in cancerous tissue, thus supporting a paracrine relationship between cancerous tissue and ANCT, which may be useful in the prevention, diagnosis and treatment of breast cancer. There was no difference in the expression of the IGF-1 receptor in both types of tissue, as proven by RT-PCR and immunohistochemistty. Conflicting results in previous studies may be due to the different methods used to measure IGF-1R expression.

Prevalence of respiratory illnesses of school children in the industrial, urban and rural areas of Singapore

An epidemiological survey of 3216 primary school children living in the industrial, urban and rural areas of Singapore revealed a high prevalence of various respiratory symptoms and illnesses, with 13.1% cough, 8.2% wheezy chest, 25.9% blocked/running nose, 4.3% sinusitis, 7.8% asthmatic attacks and 4.1% bronchitis/pneumonia. Differences in the prevalence of respiratory illnesses and lung function tests were observed among children in the three areas, but this could not be accounted for by the varying air pollution levels which have been maintained below the long-term standards set up by WHO. It was probably responsible for the differences noted.