Zika virus and its potential re-emergence in Malaysia.

Zika virus (ZIKV) has re-emerged to cause explosive epidemics in the Pacific and Latin America, and appears to be associated with severe neurological complications including microcephaly in babies. ZIKV is transmitted to humans by Aedes mosquitoes, principally Ae. aegypti, and there is historical evidence of ZIKV circulation in Southeast Asia. It is therefore clear that Malaysia is at risk of similar outbreaks. Local and international guidelines are available for surveillance, diagnostics, and management of exposed and infected individuals. ZIKV is the latest arbovirus to have spread globally beyond its initial restricted niche, and is unlikely to be the last. Innovative new methods for surveillance and control of vectors are needed to target mosquito-borne diseases as a whole.

Stability of enteroviruses on toys commonly found in kindergarten.

Hand, foot, and mouth disease (HFMD) is a contagious childhood disease caused by enteroviruses including enterovirus A71 (EV-A71), coxsackievirus A6 (CV-A6) and CV-A16 transmitted via direct and indirect contact. Different types of toy surfaces can affect the stability of viruses. Understanding the stability of enteroviruses on toys provides insightful data for effective disinfection in kindergartens or homes. Porous (ethylene-vinyl acetate mat foam, paper, pinewood, polyester fabric, and squishy polyurethane foam) and non-porous (acrylonitrile butadiene styrene plastic and stainless-steel coin) surfaces were inoculated with EV-A71 at 4, 24, and 35°C, and coxsackieviruses at 24°C. Infectious enteroviruses were recovered and titred in median tissue culture infectious dose assay (TCID50). Atomic force microscopy (AFM) images were taken from surfaces to examine association of surface roughness with virus stability. Overall, infectious enteroviruses were persistent on all non-porous and porous surfaces. Virus persistence was longest at 4°C followed by 24°C and 35°C. EV-A71 half-lives ranged between 6.4-12.8 hours at 4°C, 2.4-6.7 hours at 24°C, and 0.13-2.7 hours at 35°C. At lower virus titres exposed to 24°C, half-lives of enteroviruses ranged from 0.1-1.4 hours. Surface roughness values from AFM suggested smooth surfaces of non-porous surfaces were associated with better virus stability. Temperature, enterovirus concentration, and type of surface affected persistence and stability of enteroviruses. Our findings suggest both porous and non-porous surfaces in kindergartens allow enterovirus persistence and should be frequently disinfected to curb HFMD outbreaks in kindergartens.

The genetic basis of divergent pigment patterns in juvenile threespine sticklebacks.

Animal pigment patterns are important for a range of functions, including camouflage and communication. Repeating pigment patterns, such as stripes, bars and spots have been of particular interest to developmental and theoretical biologists, but the genetic basis of natural variation in such patterns is largely unexplored. In this study, we identify a difference in a periodic pigment pattern among juvenile threespine sticklebacks (Gasterosteus aculeatus) from different environments. Freshwater sticklebacks exhibit prominent vertical bars that visually break up the body shape, but sticklebacks from marine populations do not. We hypothesize that these distinct pigment patterns are tuned to provide crypsis in different habitats. This phenotypic difference is widespread and appears in most of the freshwater populations that we sampled. We used quantitative trait locus (QTL) mapping in freshwater-marine F2 hybrids to elucidate the genetic architecture underlying divergence in this pigmentation pattern. We identified two QTL that were significantly associated with variation in barring. Interestingly, these QTL were associated with two distinct aspects of the pigment pattern: melanophore number and overall pigment level. We compared the QTL locations with positions of known pigment candidate genes in the stickleback genome. We also identified two major QTL for juvenile body size, providing new insights into the genetic basis of juvenile growth rates in natural populations. In summary, although there is a growing literature describing simple genetic bases for adaptive coloration differences, this study emphasizes that pigment patterns can also possess a more complex genetic architecture.

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.

Varicella-zoster virus seroprevalence in healthcare workers in Kuala Lumpur, Malaysia.

Varicella-zoster virus (VZV) infections are a particular problem in healthcare settings. A survey of chickenpox was carried out amongst healthcare workers (HCWs) following potential ward exposures. A prior history of chickenpox was given by 61/98 (62.2%). Of 64 HCWs tested for VZV IgG, 10 (15.6%) were seronegative, indicating susceptibility. The sensitivity, specificity, positive predictive value, and negative predictive value of a history of prior chickenpox were 57.4%, 90%, 96.4%, and 31.0%, respectively. VZV screening of HCWs without a history of chickenpox, and vaccination of susceptible HCWs should be undertaken in this hospital.

Causative agents of hand, foot and mouth disease in University Malaya Medical Centre, Kuala Lumpur, Malaysia in 2012-2013.

Hand, foot and mouth disease (HFMD) is a childhood illness, commonly caused by enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16). In recent years, unusual HFMD outbreaks caused by coxsackievirus A6 (CV-A6) have been reported. From May 2012 to September 2013, enteroviruses were detected in 25 HFMD patients in University Malaya Medical Centre, Kuala Lumpur, Malaysia. The predominant serotypes were EV-A71 (48%) and CV-A6 (48%), followed by CV-A16 (4%). CV-A6 patients (mean age, 2.1) were significantly younger than EV-A71 patients (mean age, 3.3). There were no significant differences observed in clinical features between EV-A71 and CV-A6 patients. Since enteroviruses are difficult to differentiate clinically, the conserved 5' untranslated region (5' UTR) was used to identify enterovirus serotypes. Phylogenetic analysis of 5' UTR showed distinct clustering of viruses as EV-A71, CV-A16 and CV-A6. Further genotyping with capsid genes showed that all the EVA71 sequences belonged to subgenotype B5, while the CV-A16 sequence belonged to subgenotype B2b. CV-A6 sequences were clustered into genotypes D1 and D2, with recent isolates from Seri Kembangan, Malaysia and China. In summary, 59.5% of HFMD cases in our centre in 2012-2013 were caused by EV-A71, CV-A16 and the newly emerging CV-A6. This study also demonstrated that 5' UTR is suitable for preliminary identification of enteroviruses during HFMD outbreaks, but specific capsid genes such as VP1 and VP4/VP2 are required for further genotyping. Apart from measures to control the spread of the virus during an outbreak of HFMD, identification of EV-A71 as the etiological agent is important as EV-A71 is a major cause of severe neurological complications and potentially fatal.

A novel carbon nanotube structure formed in ultra-long nanochannels of anodic aluminum oxide templates.

We report the fabrication of a novel carbon structure consisting of uniform carbon nanotubes formed in the nanochannels of anodic aluminum oxide (AAO) templates, with the surface side open and connected by a uniform carbon sheet. The uniformity of the fabricated CNT arrays, plus the carbon film on the AAO surface interconnecting the open ends of all CNTs, constitute the major characteristics unique to our carbon structures. Some potential applications of such structures are noted.

Diagnosis of human enterovirus A71 infection in Malaysia using a commercial IgM-capture enzyme-linked immunosorbent assay and an IgM-colloidal gold immunochromatographic assay.

Hand, foot and mouth disease (HFMD) is a common childhood infection caused by many enteroviruses, including enterovirus A71 (EV-A71). As EV-A71 is associated with severe neurological disease, early diagnosis is critical for clinical and public health management. In developing countries such as Malaysia, laboratory capacity to carry out EV-A71 IgM detection is greater than that of the gold standard methods of virus culture or molecular detection. This study evaluated two diagnostic kits, EV-A71 IgM-capture enzyme-linked immunosorbent (ELISA) and EV-A71 IgM-colloidal gold immunochromatographic assay (GICA), which had previously only been assessed in China. The assays were tested with 89 serum samples from patients with suspected HFMD. The sensitivity, specificity, positive predictive value, and negative predictive value rates were 78.4%, 80.8%, 74.4%, and 84.0%, respectively, for the IgM-capture ELISA, and 75.7%, 76.9%, 70.0%, and 81.6% for the IgM GICA. These performance measures were similar between the two assays. Concordance between the two assays was 91.1%. The sensitivity rates were lower than those previously reported, likely because the multiple circulating EV-A71 genotypes in Malaysia differ from the C4 subgenotype found in China and used in the assays. Both assays had low false positive rates (12.5% and 16.7% for ELISA and GICA, respectively) when tested on sera from patients confirmed to have enteroviruses. Both diagnostic kits are suitable for early diagnosis of HFMD caused by EVA71 in Malaysia, but confirmation with culture or PCR is still important.

Predictive value of the user seal check in determining half-face respirator fit.

Guidelines issued by the Centers for Disease Control and Prevention and the World Health Organization state that healthcare workers should wear N95 masks or higher-level protection during all contact with suspected cases of severe acute respiratory syndrome. Before use, the manufacturer recommends performing a user seal check to ensure that the mask is fitted correctly. This study aimed to test the ability of the user seal check to detect poorly fitting masks. This study is a retrospective review of a mask-fitting programme carried out in the intensive care unit of the Prince of Wales Hospital in Hong Kong. In this programme, all staff were tested with two types of N95 mask and one type of N100 mask. The results of the documented user seal check were then compared with the formal fit-test results from a PortaCount. Using a PortaCount reading of 100 as the criterion for a correctly fitted mask, the user seal check wrongly indicated that the mask fitted on 18-31% of occasions, and wrongly indicated that it did not fit on 21-40% of occasions. These data indicate that the user seal check should not be used as a surrogate fit test. Its usefulness as a pre-use test must also be questioned.

Virucidal activity of Virkon S on human enterovirus.

The efficacy of Virkon S, a commercial disinfectant as a virucidal spray against human enterovirus 71 (HEV71), the causative agent of the fatal form of hand, foot and mouth disease was examined. At least one log10 reduction of HEV71 titer was achieved when one spray of Virkon (1% or 2%) with ten minutes of contact time was applied. The infectivity was completely lost when four sprays of 1% or 2% Virkon were applied, suggesting that at least four sprays of 1% Virkon to the surface bound HEV71 was necessary to completely inactivate the virus. These findings suggest that Virkon S at the proper concentration is suitable to be used as an effective and easy to use disinfectant against HEV71.

Treatment of premenstrual syndrome with fluoxetine: a double-blind, placebo-controlled, crossover study.

OBJECTIVE: Although its etiology is unknown, it has been hypothesized that premenstrual syndrome (PMS) is linked to a deficiency of central serotoninergic activity. In the present study, we evaluated the effect of fluoxetine, a specific serotonin uptake inhibitor, on PMS symptoms. METHODS: Following extensive screening, including several psychological inventories, eight women with severe persistent PMS participated in a 6-month double-blind, placebo-controlled, crossover study which included three months each of daily fluoxetine 20 mg or placebo, administered in a randomized order. Symptoms were evaluated using the Calendar of Premenstrual Experiences and other psychometric measures. RESULTS: Compared with placebo, treatment with fluoxetine was associated with an improvement in PMS symptoms as judged by highly significant decreases in behavioral (P less than .005), physical (P less than .05), and total (P less than .005) Calendar of Premenstrual Experiences scores; Beck Depression Inventory scores (P less than .005); Profile of Mood States subscales scores including depression (P less than .005), tension (P less than .005), and anger (P less than .01); and State-Trait Anxiety Inventory scores. The use of fluoxetine was associated with a greater mean reduction in behavioral (75%) than in physical scores (40%), with a mean decrease in total Calendar of Premenstrual Experiences scores of 62%, which rendered these scores similar to follicular phase values. Thus, the luteal phase symptomatology of PMS was effectively abolished. At this dose, no significant side effects or complications were noted during treatment. CONCLUSION: Fluoxetine appears to be a highly effective, well-tolerated treatment for the psychological and physical symptoms accompanying severe PMS.

Intrauterine insemination after ovarian stimulation as a treatment for subfertility because of subnormal semen: a prospective randomized controlled trial.

OBJECTIVE: To determine whether intrauterine insemination (IUI) after ovarian stimulation with human menopausal gonadotropin (hMG) gives a better pregnancy rate (PR) than natural intercourse in couples with subfertility because of subnormal semen. DESIGN: Prospective randomized controlled trial. SETTING: University based subfertility clinic. PATIENTS: Couples with subnormal semen as the only identifiable cause of subfertility. INTERVENTIONS: In control cycles, the couples had natural intercourse. In IUI cycles, IUI was performed after ovarian stimulation with hMG and human chorionic gonadotropin. MAIN OUTCOME MEASURE: The clinical PRs and complications of IUI cycles and control cycles were compared. RESULTS: There were six clinical pregnancies in the 42 IUI cycles, whereas there was no clinical pregnancy in the 42 control cycles. The clinical PR in IUI cycles (14.3% per cycle) was significantly higher than that in control cycles (0%). Six patients (14.3%) developed moderate degree of ovarian hyperstimulation syndrome in IUI cycles. CONCLUSION: Intrauterine insemination after ovarian stimulation with hMG is useful in treatment of subfertile couples with subnormal semen.

Subcutaneous primitive neuroectodermal tumour in the abdominal wall of a child: long-term survival after local excision.

Tumours of the peripheral primitive neuroectodermal tumour/Ewing's sarcoma (PNET/ES) family can rarely occur as primary lesions within the skin and subcutis. We present a case of subcutaneous PNET within the abdominal wall of a 33-month-old child. Histologically it was a small round cell tumour that marked strongly for CD99 and displayed ultrastructual evidence of neural differentiation. The tumour was completely excised, but due to an initial misdiagnosis no adjuvant therapy was given. Despite this, the patient is well without evidence of disease 10 years and 3 months after surgery. A review of similar cases reveals not all patients are as fortunate, suggesting combination therapy, including chemotherapy, is still the best treatment for these tumours, even when small and superficial. Our report therefore highlights the importance of recognising PNET/ES in the skin and subcutis so appropriate therapy can be administered.

Myxoma of the breast: report of a case and ultrastructural study.

A case of myxoma of the breast is presented. The differential diagnosis with respect to other myxoid tumours of the breast is discussed. Ultrastructurally the tumour cells show features of a primitive mesenchymal cell with possible pericytic or modified myoepithelial cell differentiation. The histogenesis is discussed.

Infantile hemangioendothelioma of the liver: ultrastructural study of a type II case.

A case of infantile hemangioendothelioma of the liver presenting with congestive heart failure and massive hepatomegaly in a two-mth old baby is described. Serum alpha-fetoprotein was elevated in this patient and clinically the lesion might not be distinguishable from other, commoner hepatic tumours in children. Histologically the tumour showed a type II pattern as defined by Dehner. The significance of classifying this tumour into two histologic types is discussed. Only 3 cases reported in the English literature were studied by electron microscopy; two of them were type I while the other was a type II lesion. In our case the endothelial cells appeared ultrastructurally less differentiated and architecturally more disorganized than in type I lesions. Like the previous case, the basal lamina showed marked thickening and reduplication. The significance of these findings is discussed.

Clear cell chondrosarcoma: case report and ultrastructural study.

A case of clear cell chondrosarcoma in a Chinese patient is described. The clear cells showed strongly positive S-100 protein immunoreactivity. Ultrastructurally 2 types of chondroid cells were demonstrated. One type appeared more primitive with abundant electron-lucent cytoplasm and sparse organelles. The other type of cell was more differentiated with presence of microvilli and numerous dilated cisternae of endoplasmic reticulum. Previous ultrastructural studies on these lesions were reviewed and compared with the present findings.

Ovarian Sertoli-Leydig cell tumor with retiform pattern.

Sertoli-Leydig cell tumors (SLCT) are sex cord-stromal tumors which exhibit testicular differentiation.1 They account for less than 0.2% of ovarian neoplasms in total but comprise 4% of ovarian tumors in females under 20 yrs of age.2 The morphological appearance of these tumors varies more widely than that of any other ovarian tumor except for the teratomas. Histologically they are now classified into 5 categories: well-differentiated, intermediately differentiated, poorly differentiated, heterologous and retiform.1 We describe the case of an ovarian Sertoli-Leydig cell tumor with retiform pattern in a 7 yr old girl.