A 10-year systematic review and meta-analysis of determinants of postpartum depression in the Association of Southeast Asian Nations countries

INTRODUCTION

Postpartum depression (PPD) is a mental and emotional condition that can affect women during their first postnatal year and concern globally. This study aimed to determine the overall prevalence and determinants of postpartum depression (PPD) in Association of Southeast Asian Nations (ASEAN) countries.

MATERIALS AND METHODS

A systematic search of observational studies conducted in ASEAN countries between 1 January 2010 and 31 December 2020 was performed in the Medline, PubMed and Google Scholar databases. The quality of studies was evaluated based on The Joanna Briggs Institute Checklist. The analysis was performed with Review Manager software version 5.4. Metaanalysis of the estimates from primary studies was conducted by adjusting for possible publication bias and heterogeneity.

RESULTS

Twenty-five studies including 19924 postnatal mothers were included in this review. The pooled prevalence of PPD is 22.32% (95% CI: 18.48, 26.17). Thailand has the highest prevalence of PPD with a pooled prevalence of 74.1% (95% CI: 64.79, 83.41). The prevalence of PPD was highest when the assessment for PPD was conducted up to 6 weeks postpartum with a pooled prevalence of 25.24% (95% CI: 14.08, 36.41). The identified determinants of PPD were unplanned pregnancy, term pregnancy, lack of family support and physical violence. There were limited studies done and high heterogeneity in terms of quality, methodology, culture, screening method and time of PPD measurement.

CONCLUSIONS

Approximately one in five postpartum women in ASEAN countries had PPD. The risk factor that lowers the risk of PPD is unplanned and term pregnancies, while women with a lack of family support and experienced physical violence increase the risk of PPD. Robust prevalence studies are needed to assess the magnitude of this problem in ASEAN countries.

Characterisation of the immune microenvironment of primary breast cancer and brain metastasis reveals depleted T-cell response associated to ARG2 expression

BACKGROUND

Immune checkpoint inhibition is an established treatment in programmed death-ligand 1 (PD-L1)-positive metastatic triple-negative (TN) breast cancer (BC). However, the immune landscape of breast cancer brain metastasis (BCBM) remains poorly defined.

MATERIALS AND METHODS

The tumour-infiltrating lymphocytes (TILs) and the messenger RNA (mRNA) levels of 770 immune-related genes (NanoString™, nCounter™ Immuno-oncology IO360) were assessed in primary BCs and BCBMs. The prognostic role of ARG2 transcripts and protein expression in primary BCs and its association with outcome was determined.

RESULTS

There was a significant reduction of TILs in the BCBMs in comparison to primary BCs. 11.5% of BCs presented a high immune infiltrate (hot), 46.2% were altered (immunosuppressed/excluded) and 34.6% were cold (no/low immune infiltrate). 3.8% of BCBMs were hot, 23.1% altered and 73.1% cold. One hundred and twelve immune-related genes including PD-L1 and CTLA4 were decreased in BCBM compared to the primary BCs (false discovery rate <0.01, log2 fold-change >1.5). These genes are involved in matrix remodelling and metastasis, cytokine-chemokine signalling, lymphoid compartment, antigen presentation and immune cell adhesion and migration. Immuno-modulators such as PD-L1 (CD274), CTLA4, TIGIT and CD276 (B7H3) were decreased in BCBMs. However, PD-L1 and CTLA4 expression was significantly higher in TN BCBMs (P = 0.01), with CTLA4 expression also high in human epidermal growth factor receptor 2-positive (P < 0.01) compared to estrogen receptor-positive BCBMs. ARG2 was one of four genes up-regulated in BCBMs. High ARG2 mRNA expression in primary BCs was associated with worse distant metastasis-free survival (P = 0.038), while ARG2 protein expression was associated with worse breast-brain metastasis-free (P = 0.027) and overall survival (P = 0.019). High transcript levels of ARG2 correlated to low levels of cytotoxic and T cells in both BC and BCBM (P < 0.01).

CONCLUSION

This study highlights the immunological differences between primary BCs and BCBMs and the potential importance of ARG2 expression in T-cell depletion and clinical outcome.

Novel imidazolium-thiohydantoin hybrids and their Mn(iii) complexes for antimicrobial and anti-liver cancer applications

We present the effective synthesis and structural characterization of three novel imidazolium-thiohydantoin ligands (IMTHs, 5a–c) and their Mn(iii) complexes (Mn(iii)IMTHs, 6a–c) in this study. The findings of elemental analyses, spectral analyses and magnetic measurements will be used to infer the stoichiometry, coordination styles, and geometrical aspects of Mn(iii)IMTHs. The new compounds were evaluated for their chemotherapeutic potential against ESKAPE pathogens and liver cancer (HepG2). According to the MIC and MBC values, the bactericidal and bacteriostatic activities of IMTHs have been significantly improved following coordination with the Mn(iii) ion. The MTT assay results showed that all Mn(iii)IMTHs had the potential to reduce the viability of liver carcinoma (HepG2) cells in a dose-dependent manner, with the BF₄-supported complex (6b) outperforming its counterparts (6a and 6c) as well as a clinical anticancer drug (VBL). Additionally, Mn-IMTH₂ (6b) showed the highest level of selectivity (SI = 32.05) for targeting malignant cells (HepG2) over healthy cells (HL7702).

We present the effective synthesis and structural characterization of three novel imidazolium-thiohydantoin ligands (IMTHs, 5a–c) and their Mn(iii) complexes (Mn(iii)IMTHs, 6a–c) in this study.

P14.70 BMScope: A systematic mapping review of brain/leptomeningeal metastasis clinical studies from 2010 to 2020

BACKGROUND

Brain metastasis (BM) and leptomeningeal disease (LMD) are typified by a poor prognosis and are an area of unmet clinical need. Historically, patients with central nervous system (CNS) disease have been excluded from systemic therapy clinical trials, particularly with active/leptomeningeal disease. However, increasing prevalence of CNS metastasis is leading to greater interest in BM/LMD. We performed a descriptive analysis of clinical studies investigating BM/LMD management, published between Jan 2010 to Mar 2020.

METHODS

A comprehensive, customised search strategy was devised for 12 online bibliographic databases, using the following concepts: “clinical study”, “brain metastasis”, “leptomeningeal disease”, “intervention”, “patient-related outcome”. Double screening for inclusion/exclusion was performed on the Rayyan QCRI web application. Published abstracts were also screened for inclusion from ASCO, ESMO, SNO and EANO between 2015–2020. Following full text screening, conflicts were resolved by consensus and data were extracted using an online standardised tool. Data analysis and data visualisation were performed on the R statistical package.

RESULTS

Overall, 33118 published studies were double screened; 2632 full publications and 628 abstracts were included. Of these, 14.7% reported on unique interventional clinical trials (phase 2 = 267; phase 3 = 80). More than three times the number of clinical trials investigating systemic agents as the sole therapy for BM/LMD were published in Q1 2020 compared to the whole of 2010 (16 vs 5). 42.5% of clinical trials employed a form of local therapy (brain targeted radiotherapy or neurosurgery). Studies reported on patients with BM (n = 2738), LMD (n = 110) or both (n = 119). The majority of studies were performed in North America, Europe or East Asia (88.5% vs 11.5% rest of the world). The top 3 nations involved in published studies were the USA (n = 1155), China (n = 351) and Germany (n = 334). Network analysis demonstrated increasing links between countries. In line with expected BM prevalence, the main tumour sites studied were lung (23.4%), gastrointestinal (17.5%), breast (15%) and melanoma (12.5%). A rising trend of published BM/LMD studies over time was noted, with 83 observational studies/10 clinical trials in 2010 vs. 454 observational studies/80 clinical trials in 2019.

CONCLUSION

These findings demonstrate that over the last decade there has been a growth in BM/LMD research; likely reflecting an increasing disease prevalence, availability of novel and potentially CNS active agents, as well as more advanced local therapy modalities. BM/LMD clinical research is dominated by a few geographical regions and nations; however, there is an apparent shift to more international collaboration. This comprehensive mapping exercise will enable targeted systematic reviews of the existing evidence base on BM/LMD management.

Haemorrhagic shock from solid tumours of the adrenal gland: a case of bleeding primary adrenal lymphoma

Suprarenal or adrenal gland haemorrhage is an uncommon but potentially lethal condition if unrecognised. Adrenal masses rarely present with haemorrhage, but they remain an important differential aetiology for adrenal bleeding. We present a novel case of primary adrenal lymphoma with adrenal haemorrhage in a middle-aged woman who presented with right-sided abdominal pain and class 1 haemorrhagic shock. She was found to have spontaneous unilateral adrenal gland haemorrhage in the absence of any underlying previous pathology. Presenting features, diagnosis and subsequent oncological management are reported.

Sustainable operation and maintenance criteria for non-toll road green rating system

Green Rating System is utilized as tools to analyze the sustainability of buildings or infrastructures. Improvising green rating system is a continuous effort due to the needs of local implementation of a country. In Malaysia, there are two established rating systems for roads; MyGHI for highways and pHJKR (Roads) for non-tolled roads. Preliminary study on pHJKR (Roads) identified this rating tool assess road sustainability performance only at planning, design & construction stages. This study foresees, it is essential to sustain its engineering and sustainability performance, including carbon assessment under Operation and Maintenance (O&M). Therefore, this paper highlights the relevance and applicability of pHJKR (Roads) in comparison to other establish green road rating tools. The assessment criteria and elements during (O&M) phase are proposed for score development, which extensive research will lead to the establishment of O&M pHJKR (Roads). The data was gathered and analysed from a comprehensive review of current pHJKR (Roads) with a comparison other green road rating index. The expert panel discussion also was utilized to determine suitable sustainability factors. This study, in conclusion providing an opportunity to the enhancement of pHJKR (Roads), which offer a complete cycle of assessment in road project development of road Green Rating System.

P113 Efficacy, safety and long-term durability of endovascular treatment of MCA aneuryms: a review of 161 treated aneurysms

Objectives

The aim of this study was to assess the long-term outcomes of endovascular treatment of MCA aneurysms and identify factors associated with recurrence.

Subjects

161 aneurysms in 147 patients treated between January 2008 and August 2011.

Methods

A retrospective case note review was performed. Aneurysm occlusion was assessed using the Raymond-Roy classification. Clinical outcome was graded using the mRS.

Results

The minimum period of follow up was 65 months, with a maximum follow up period of 120 months. 49% of aneurysms were ruptured at the time of treatment. Morbidity was observed in 15% of the unruptured aneurysms (6% permanent neurological deficit), and in 33% of ruptured aneurysms (15% permanent neurological deficit). 84% of aneurysms were fully occluded following first treatment. Of these, 34% demonstrated angiographic recurrence and 10% required re-intervention. 25% of aneurysms≤7 mm in maximal diameter demonstrated angiographic recurrence, as compared with 50% of aneurysms>7 mm. Aneurysm size >7 mm was associated with a significantly shorter time to recurrence (log rank=9.655, p=0.002).

Conclusions

This is a large series of MCA aneurysms with a long period of follow up. Our results demonstrate that endovascular treatment of MCA aneurysms is associated with a low morbidity and mortality. Given the increasing use of adjunctive devices (stents, web devices) full occlusion of ruptured aneurysms in the acute phase is not necessary, and deliberate staged treatment a reasonable strategy.

Abstract P6-05-02: Identification of microRNAs differentially expressed in brain metastasis secondary to breast cancer

Background: Despite sequential improvements in the adjuvant treatment of breast cancer (BC), recurrence and metastasis remains a major clinical problem and in particular, brain metastasis (BCBM). A number of microRNAs (miRNAs) have been linked to the metastatic process in BC, but to date there is limited work on the microRNAs involved in BCBM. The current study aim to identify differentially expressed miRNAs within primary breast cancer who did not recur (BCNR) versus primary BC cases which did recur (BCR) and their matched BCBM cases.

Methods: Formalin-fixed paraffin-embedded (FFPE) material was collected of 12 primary BCNRs from the Liverpool tissue bank and of 40 paired primary BCR samples and their matched BCBM from the Walton Research Tissue Bank and RCSI National Breast Cancer Bioresource. miRNA was extracted (Qiagen miRNeasy FFPE kit) and profiled using the NanoString™ nCounter™ miRNA Expression Assay (Human v3 miRNA). The differentially expressed miRNAs between BCNR versus BCR and BCR versus their matched BCBM were identified by significance of microarray analysis (SAM) on the MeV4.9 software. Pathway analysis was performed using the DIANA-mirPath v3.0 software and the Ingenuity Pathway Analysis (IPA) to identify a network of genes/pathways regulated by the differentially expressed miRNAs.

Results: 12 BCNR and 30 matched pairs of BCR and BCBM passed the quality control and normalisation processes. Principal component analysis (PCA) performed on 166 miRNAs after QC/normalisation clearly distinguishes the BCNR and the primary BCR from the matched BCBM cases, whereas SAM revealed 58 differentially expressed miRNAs with a 10% FDR (false discovery rate) and an absolute log2 fold-change (FC) &gt;1 between BCNR and BCR and 11 between the matched BCs and BCBMs. Pathway clustering revealed that these differentially expressed miRNAs (10% FDR, log2FC&gt;1) within both BCNR vs BCR and BCR vs BCBM cohorts are highly enriched for genes involved in extracellular matrix (ECM)-receptor interactions, proteoglycans, adherens junctions, TGF-β, p53 and Hippo signalling. IPA identified a network of genes, implicated in the processes of breast cancer invasion and metastasis, regulated by the identified miRNAs, such as, TWIST, MET, TP53, MYC, EZH2, ZEB1, TAGLN and BIRC5. Four of the significantly differentially expressed miRNAs, hsa-miR-132-3p, hsa-miR-199a-5p, hsa-miR-150-5p and hsa-miR-155-5p were present within both cohorts (BCNR vs BCR and BCR vs BCBM) and regulate genes involved in Hippo and TGF-β signalling (DIANA-mirPath v3.0 analysis: p=5.23x10-08 and p=2.67x10-07 respectively).

Conclusion: The current study, utilising a large cohort of paired BCR and BCBM cases, provides novel insight into the molecular mechanisms and role of miRNAs in BCBM. Four miRNAs (hsa-miR-132-3p, hsa-miR-199a-5p, hsa-miR-150-5p and hsa-miR-155-5p) in particular could be potentially used to identify patients with increased risk of developing brain metastasis and help facilitate the development of specific treatments for BCBM, which to date have proved elusive. The miRNAs identified require further exploration as potential biomarkers as well as novel therapeutic targets.

Citation Format: Giannoudis A, Clarke K, Zakaria R, Vareslija D, Farahani M, Rainbow L, Platt-Higgins A, Ruthven S, Brougham K, Rudland PS, Jenkinson MD, Young L, Falciani F, Palmieri C. Identification of microRNAs differentially expressed in brain metastasis secondary to breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-05-02.

Lipopolysaccharide-induced memory impairment in rats: a model of Alzheimer's disease

Alzheimer's disease (AD) is a primary cause of dementia in the middle-aged and elderly worldwide. Animal models for AD are widely used to study the disease mechanisms as well as to test potential therapeutic agents for disease modification. Among the non-genetically manipulated neuroinflammation models for AD, lipopolysaccharide (LPS)-induced animal model is commonly used. This review paper aims to discuss the possible factors that influence rats' response following LPS injection. Factors such as dose of LPS, route of administration, nature and duration of exposure as well as age and gender of animal used should be taken into account when designing a study using LPS-induced memory impairment as model for AD.

Abstract P2-03-04: Application of digital-PCR technology to determine c-MET copy number variation in paired primary breast cancer and brain metastases

INTRODUCTION:

c-MET amplification/overexpression has been associated with treatment failure and progression in many cancers, including breast cancer (BC). c-MET showed amplification by fluorescent in situ hybridization (FISH) in 27% of trastuzumab-treated HER2-positive patients. These patients had a high trastuzumab failure rate and a shorter time to progression. Up to 50% of patients with metastatic HER2-positive disease will develop brain metastases (BM) during their disease course and in approximately one third, brain is the first site of progression. Amplification/copy number variations (CNVs) are mainly assessed by FISH whereas overexpression is assessed by immunohistochemistry (IHC). We present a PCR-based assay (digital-PCR) able to determine CNV in c-MET and HER2 in a cohort of patients with metastatic BC to the brain and demonstrate the correlation of CNV to protein expression.

METHODS:

DNA was isolated from paraffin-embedded tissues of 23 paired primary BC-BM cases. CNV was analysed by the QuantStudioTM 3D-Digital-PCR (QS3D) and real-time qPCR (both from ThermoFisher Scientific). The breast MCF7, T47D, BT474, AU565, SKBR3 and the gastric MKN45 cell lines were used as controls for the HER2 and c-MET CNV assays. Copy number per diploid genome was calculated using the absolute quantification number of FAM-labelled target and VIC-labelled RNaseP reference multiplied by 2. Cases with ≤2 copies are classified as normal whereas cases with &gt;2 were classified as amplified. The HER2 positivity of the primary BC cases was routinely assessed by IHC. The c-MET protein expression was assessed by IHC using the c-MET(3D4) monoclonal antibody (ThermoFisher Scientific).

RESULTS:

CNV in c-MET by QS3D digital-PCR was detected in 69.6% of primary BC (ER-/HER2+:2, ER+/HER2+:5, ER+/HER2-:8, Triple-negatives:5, unknown:3) as well as 69.6% of BM, whereas HER2 CNV was observed in 39.1% primary BC and 52.2% BM. In the HER2-positive cases, the prevalence of HER2 CNV was 100% in both primary BC and BM. Within these cases, c-MET CNV was 85.7% in the primary BC and 71.43% in BM. CNVs in both genes were observed in 30.4 % of all primary and 39.1% of BM. The CNV data are presented in Table 1.

CNV data for c-MET and HER2 between primary breast cancer (BC) and corresponding brain metastatic (BM) casesc-MET CNVHER2 CNVBCBMBCBM&gt;2: 16&gt;2: 12≤2: 4&gt;2: 9&gt;2: 8≤2: 1≤2: 7&gt;2: 4≤2: 3≤2: 14&gt;2: 4≤2: 10

There was a high concordance between the QS3D and qPCR data with Pearson's R=0.74 (p&lt;0.00001).

A significant correlation between HER2 protein expression and CNV was observed (Fisher's exact test p=0.0005). Data will be presented on c-MET protein expression in the pair samples.

CONCLUSIONS:

The prevalence of CNV is much higher than that reported by immunohistochemistry and FISH in the literature to date, possibly due to the sensitivity of the digital-PCR technology. The high level of c-MET CNV in primary and metastatic BC, and the concurrent CNV in both genes warrants further investigation. It also highlights the potential to use c-MET directed therapy particularly in HER2+ BC and reinforces the potential importance of precise detection methods in both the primary and metastatic setting. Analysis of a larger series is currently on-going.

Citation Format: Giannoudis A, Zakaria R, Platt-Higgins A, Syed KAR, Ashton K, Dawson T, Rudland PS, Holcombe C, Jenkinson MD, Palmieri C. Application of digital-PCR technology to determine c-MET copy number variation in paired primary breast cancer and brain metastases [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-03-04.

Insight into potential mechanisms of hypobaric hypoxia-induced learning and memory deficit - Lessons from rat studies

Impairment of memory is one of the most frequently reported symptoms during sudden hypoxia exposure in human. Cortical atrophy has been linked to the impaired memory function and is suggested to occur with chronic high-altitude exposure. However, the precise molecular mechanism(s) of hypoxia-induced memory impairment remains an enigma. In this work, we review hypoxia-induced learning and memory deficit in human and rat studies. Based on data from rat studies using different protocols of continuous hypoxia, we try to elicit potential mechanisms of hypobaric hypoxia-induced memory deficit.

Development of a PVS2 droplet-vitrification cryopreservation technique for Aranda Broga Blue orchid protocorm-like bodies (PLBs)

　　BACKGROUND: Conservation of commercially important ornamental plants is important to maintain its unique beauty to cater the market demands.

OBJECTIVE

The main objective is to develop an efficient cryopreservation technique for Aranda Broga Blue orchid PLBs using droplet-vitrification method.

MATERIALS AND METHODS

Several critical factors in cryopreservation were accessed such as preculture concentrations and durations, choice of vitrification solutions, two-step or three-step vitrification, growth recovery medium and PVS2 exposure duration.

RESULTS

The best growth regeneration percentage (5%) was obtained when 3-4mm PLBs were precultured in 0.2M sucrose for 3 days, followed by osmoprotection for 20 minutes, dehydration in PVS2 for 20 minutes at 0 degree C, LN storage, thawed and unloading for 20 minutes, and growth regeneration in VW10 medium. PLBs were found to be very sensitive to osmotic stress imposed by high molecular weight cryoprotectant such as sucrose and glycerol. Osmotic potential of growth recovery medium is one of the main factors that affect growth recovery in cryopreserved PLBs.

CONCLUSION

Current report showed possibilities in cryopreserving Aranda Broga Blue PLBs using droplet-vitrification technique. However, further improvement of growth recovery can be done by focussing on approaches that facilitate sufficient water removal from PLBs without causing severe osmotic injuries to the plant cells.

Nonlinear optical response of platinum nanostructures and application for water detection in transformer oil

We report the fabrication of platinum nanostructures on an ITO substrate (Pt-NSs).

The Potential Role of Melatonin on Memory Function: Lessons from Rodent Studies

Pineal melatonin biosynthesis is regulated by the circadian clock located in the suprachiasmatic nucleus of the hypothalamus. Melatonin has been found to modulate the learning and memory process in human as well as in animals. Endogenous melatonin modulates the process of newly acquired information into long-term memory, while melatonin treatment has been found to reduce memory deficits in elderly people and in various animal models. However, the mechanisms mediating the enhancing effect of melatonin on memory remain elusive. This review intends to explore the possible mechanisms by looking at previous data on the effects of melatonin treatment on memory performance in rodents.

Z-scan studies of the nonlinear optical properties of gold nanoparticles prepared by electron beam deposition

This paper details the fabrication process for placing single-layer gold (Au) nanoparticles on a planar substrate, and investigation of the resulting optical properties that can be exploited for nonlinear optics applications. Preparation of Au nanoparticles on the substrate involved electron beam deposition and subsequent thermal dewetting. The obtained thin films of Au had a variation in thicknesses related to the controllable deposition time during the electron beam deposition process. These samples were then subjected to thermal annealing at 600°C to produce a randomly distributed layer of Au nanoparticles. Observation from field-effect scanning electron microscope (FESEM) images indicated the size of Au nanoparticles ranges from ∼13 to ∼48  nm. Details of the optical properties related to peak absorption of localized surface plasmon resonance (LSPR) of the nanoparticle were revealed by use of UV-Vis spectroscopy. The Z-scan technique was used to measure the nonlinear effects on the fabricated Au nanoparticle layers where it strongly relates LSPR and nonlinear optical properties.

Plasmon enhanced organic devices utilizing highly ordered nanoimprinted gold nanodisks and nitrogen doped graphene

High performance organic devices including polymer solar cells (PSCs) and light emitting diodes (PLEDs) were successfully demonstrated with the presence of highly ordered nanoimprinted Au nanodisks (Au NDs) in their solution-processed active/emissive layers, respectively. PSCs and PLEDs were fabricated using a low bandgap polymer and acceptor, nitrogen doped multiwalled carbon nanotubes poly[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl] thieno[3,4-b]-thiophenediyl] (n-MWCNTs:PTB7), and [6,6]-phenyl C71 butyric acid methyl ester (PC71BM) and (4,4-N,N-dicarbazole) biphenyl (CBP) doped with tris(2-phenylpyridine) iridium(iii) (Ir(ppy)3) as active/emissive layers, respectively. We synthesized nitrogen doped graphene and used it as anodic buffer layer in both devices. The localized surface plasmon resonance (LSPR) effect from Au NDs clearly contributed to the increase in light absorption/emission in the active layers from electromagnetic field enhancement, which originated from the excited LSPR in PSCs and PLEDs. In addition to the high density of LSPR and strong exciton-SP coupling, the electroluminescent (EL) enhancement is ascribed to enhanced spontaneous emission rates. This is due to the plasmonic near-field effect induced by Au NDs. The PSCs and PLEDs exhibited 14.98% (8.08% to 9.29%) under one sun of simulated air mass 1.5 global (AM1.5G) illumination (100 mW cm(-2)) and 19.18% (8.24 to 9.82 lm W(-1)) enhancement in the power conversion efficiencies (PCEs) compared to the control devices without Au NDs.

Larvicidal efficacy screening of Anacardaciae crude extracts on the dengue hemorrhagic vector, Aedes aegypti

Vector-borne diseases are still rife because of the re-emergence of diseases transmitted by mosquitoes. The objective of this paper is to evaluate the larvicidal efficacy of crude leaf extract of Mangifera indica, Gluta renghas, and Melanochyla fasciculiflora against vector of dengue hemorrhagic fever, Aedes aegypti. These plant species are endemic species and widely distributed in Malaysian forests. Leaves of Ma. indica, G. renghas and M. fascculiflora were collected from Teluk Bahang National Park, Penang Malaysia. Fractions of leaves were segregated, air-dried, powdered and extracted using Soxhlet with methanol. The solvent was removed by using rotary evaporator to obtain the crude extract. Using WHO standard larval bioassay test method, third instar larvae of Aedes aegypti were exposed to concentration ranging from 200- 4500 ppm of methanol extract for all plant species. Larval mortality was observed after 24 hours exposure. The highest susceptibility and toxicity was recorded by Mangifera indica with the lowest concentration at 800 ppm followed by M. fasciculiflora and G. renghas. This indicates that crude plant extract is very effective in killing Ae. aegypti mosquitoes. This finding may lead to new low cost alternative, environmentally friendly method for mosquito control programs. To our knowledge, this is the first report on larvicidal bioefficacy from endemic Malaysian plants.

The management of bifocal intracranial germinoma in children

OBJECTIVES

Bifocal intracranial germinoma (BFG) is a tumour of the pineal and suprasellar regions, which is known to be highly radiosensitive. The definitive treatment and outcomes are not well defined, particularly in the paediatric population. We review our series of purely paediatric cases from a single institution and combine them with the limited reports in the literature to determine the results of different management strategies.

METHODS

Four patients were treated at our institution with a median age of 15.3 years. A literature search identified a further 38 paediatric cases with a median age of 12.9 years.

RESULTS

All four patients had normal serum and CSF tumour markers. One patient had a diagnosis made based on imaging findings of bifocal pineal and suprasellar lesions presenting with diabetes insipidus. Three others underwent biopsy. All had craniospinal radiotherapy, which has led to complete cure with no cases of progression at a mean follow-up of 3 years. The most common treatment modality in published cases is craniospinal irradiation. In the cases reviewed, limited radiation treatments (whole ventricle or focal) combined with chemotherapy regimens yield comparable outcomes where there is no spinal dissemination. Outcomes do not appear to be altered by biopsy in cases with negative tumour markers and characteristic imaging appearances.

CONCLUSION

Patients who present with a classic appearance of germinoma, negative tumour markers and diabetes insipidus probably do not require a biopsy to confirm the diagnosis. No evidence of dissemination may obviate the need for craniospinal irradiation, but good quality long-term follow-up data are required to demonstrate the benefits of combined focal radiotherapy and chemotherapy regimes.

Green tea polyphenol–reduced graphene oxide: derivatisation, reduction efficiency, reduction mechanism and cytotoxicity

This paper reports on the derivatisation, reduction efficiency, reduction mechanism and cytotoxicity of green tea polyphenol–reduced graphene oxide (GTP–RGO).

Melatonin and its agonists in pain modulation and its clinical application

Melatonin, the hormone of darkness has many physiological functions in the body and also exerts a number of pharmacological effects. Most of these actions of melatonin are mediated through melatonin membrane receptors like MT1/MT2 receptors or through nuclear orphan receptors like RZR/ROR receptors or through calcium binding proteins in the cytosol. The finding that pain perception is circadian in nature has prompted many to suggest that "pain modulation" is one of the most important physiological functions of melatonin. By using a number of animal models of pain perception, it has been found that melatonin exerts antinociceptive and antiallodynic effects. Number of studies has shown that melatonin modulates pain perception by acting through opioid receptors, NMDA receptors and G-protein, and they have been analyzed using specific antagonists like naloxone or NMDA-G protein receptor antagonists. Recently it has been shown that melatonin exerts its antinociceptive effects through MT1 and MT2 melatonergic receptors located in the dorsal region of the spinal cord as well as in various parts of the brain concerned with pain modulation. Evidences for this have been obtained by using common melatonergic receptor antagonist like luzindole or specific MT2 receptor antagonist like 4P-PDOT or K-185. In a few clinical studies undertaken during surgery, melatonin has been shown to have analgesic effects. Melatonin is emerging as a new analgesic drug with a novel mechanism of actions and has the potential to be used as a natural pain killer in inflammatory, neuropathic pain conditions and also during surgical procedures.

Thalamic physiology of intentional essential tremor is more like cerebellar tremor than postural essential tremor

The neuronal physiological correlates of clinical heterogeneity in human essential tremor are unknown. We now test the hypothesis that thalamic neuronal and EMG activities during intention essential tremor are similar to those of the intention tremor which is characteristic of cerebellar lesions. Thalamic neuronal firing was studied in a cerebellar relay nucleus (ventral intermediate, Vim) and in a pallidal relay nucleus (ventral oral posterior, Vop) during stereotactic surgery for the treatment of tremor. Nine patients with essential tremor were divided clinically into two categories: one with a substantial component of tremor with intention (termed intention ET) and the other without (postural ET). These types of essential tremor were compared with patients having intention tremor plus other clinical signs of cerebellar disease (cerebellar tremor). Neurons in patients with either intention ET or cerebellar tremor had lower firing rates and lower spike×EMG coherence than those in patients with postural ET. Patients with intention ET had a lower spike×EMG phase lead than those with postural ET. Overall, thalamic activity measures of intention ET were different from postural ET but not apparently different from those of cerebellar tremor. One patient with the intention ET (number 4) had a good response to a left thalamotomy and then suffered a right cerebellar hemispheric infarct five years later. After the stroke the intention ET recurred, which is consistent with our hypothesis that intention ET is similar to that of the intention tremor which is characteristic of cerebellar lesions.

Fatal mediastinal biopsy: How interventional radiology saves the day

This was a case of a 35-year-old man with mediastinal mass requiring computed tomography (CT)-guided biopsy for tissue diagnosis. A posterior approach with an 18-gauge biopsy needle was used to obtain tissue sample. Post biopsy, patient condition deteriorated and multiphase CT study detected active bleeding in arterial phase at the biopsy site with massive hemothorax. Subsequent angiography showed arterial bleeder arising from the apical branch of the right pulmonary artery. Selective endovascular embolization with NBCA (n-Butyl cyanoacrylate) was successful. Patient survived the complication. The case highlighted a rare complication in a common radiology procedure and the value of the interventional radiology unit in avoiding a fatal outcome.

Note: Fabrication of tapered fibre tip using mechanical polishing method

Tapered fibre tips fabricated using mechanical polishing method is studied. The fibre tips are formed by sequential polishing flat-ended single mode fibres with decreasing aluminium oxide polishing film grit size. Based on the proposed technique, tapered fibre tips with cone angle ranging from 30° to 130° are fabricated by controlling the polishing angle. Besides the variety of cone angle, considerable smoothness of the fibre tip surface may assist in good metal coating and hence a well-defined aperture can be obtained. In addition, this paper presents a two-step hybrid fabrication method combining the proposed polishing method with chemical etching method to increase the possible fibre tip cone angles achievable by chemical etching method.

A cyber medical center

This paper describes the design and implementation of a Cyber Medical Center (CMC) using web technology. The intention is to overcome the inefficiency of the traditional filing system for patients' medical records, which are considered to be time and space consuming. Another objective is to enhance the interaction between the user - the patient in this case - and the medical center personnel - the doctors and staff. This task is achieved by developing a cyber medical center interfaced with the Internet to provide direct public access. The traditional filing system is replaced by a database system for maintaining the electronic medical records of all patients in the medical center. The doctors or staff can either view the medical records or update them through the Intranet/Internet. This system has been successfully developed, implemented and tested on the Intranet platform. It will be available in a university medical center for practical use.

Mathematical modelling of MSW incineration on a travelling bed

The rising popularity of incineration of municipal solid waste (MSW) calls for detailed mathematical modelling and understanding of the incineration process. In this paper, governing equations for mass, momentum and heat transfer for both solid and gaseous phases in a moving bed in a solid-waste incineration furnace are described and relevant sub-models are presented. The burning rates of volatile hydrocarbons in the moving bed of solids are limited not only by the reaction kinetics but also the mixing of the volatile fuels with the under-fire air. The mixing rate is averaged across a computation cell and correlated to a number of parameters including local void fraction of the bed, gas velocity and a length scale comparable to the particle size in the bed. A correlation equation is also included to calculate the mixing in the freeboard area immediately next to the bed surface. A small-scale fixed bed waste incinerator was built and test runs were made in which total mass loss from the bed, temperature and gas composition at different locations along the bed height were measured. A 2-D bed-modelling program (FLIC) was developed which incorporates the various sub-process models and solves the governing equations for both gases and solids. Thermal and chemical processes are mainly confined within a layer about 5-9 times in thickness of the averaged particle size in the burning bed. For a large part of the burning process, the total mass loss rate was constant until the solid waste was totally dried out and a period of highly rising CO emission followed. The maximum bed temperature was around 1200 K. The whole burning process ended within 60 min. Big fluctuations in species concentration were observed due to channelling and subsequent 'catastrophic' changes in the local bed conditions. Reasonably good agreement between modelling and measurements has been achieved. Yet the modelling work is complicated by the channelling phenomenon in the bed. Numerical simulations without consideration of the channelling effect produced very good agreement with experiments concerning the total mass loss, but significant discrepancy exists for temperature and gas composition profiles. Transient phenomena such as the breaking of waste particles and the "catastrophic" creation of new burning channels occurring during waste incineration is a vital area requiring further investigation at the fundamental level. The underlying theory of bed behaviour must be extended to include these transient events.

Short report: differences in dihydrofolate reductase but not dihydropteroate synthase alleles in Plasmodium falciparum isolates from geographically distinct areas in Malaysia

Dihydropteroate synthase (dhps) and dihydrofolate reductase (dhfr) alleles were typed in 67 Malaysian Plasmodium falciparum isolates. The isolates were collected from two geographically distinct locations: 51 from Sabah, Malaysian Borneo, where sulfadoxine/pyrimethamine (SDX/PYR) is used to treat uncomplicated malaria and 16 from Peninsular Malaysia where in vivo resistance to SDX/PYR has been reported. A total of seven dhps alleles were identified with no significant difference in allele frequency between the 2 populations. Two of the dhps alleles described here have not been previously reported. Four dhfr alleles were detected in 67 P. falciparum isolates. Eighty-seven percent of the isolates from the Peninsula, where clinical SDX/PYR failure has been reported, had dhfr alleles with triple point mutations while all of the isolates from Sabah had dhfr alleles with 2 or less point mutations. The difference in dhfr allele frequency between the two populations was highly significant. There was no correlation between in vitro PYR response and accumulation of dhfr point mutations.

Cyproterone acetate and reversal of the impaired endometrial decidualization in streptozotocin-diabetic pseudopregnant rats

Reproductive dysfunction in the female diabetic rat is associated with impaired hypothalamic-hypophyseal system, anovulation, insufficiency of ovarian steroidogenesis and spontaneous failure of pregnancy. Formation of decidua, the highly modified endometrium of pregnancy and pseudopregnancy could only be achieved when the uterus was sensitized by a sequence of oestrogen and progesterone. In this study, we examined whether the impaired expression of endometrial decidualization in the pseudopregnant rat is linked with diabetes-associated hypersecretion of testosterone. Rats were made pseudopregnant by sterile mating. Diabetes was induced by streptozotocin on day 1 p.c. Deciduogenic stimulus was given on day 5 p.c. Treatment of cyproterone acetate (10 mg kg(-1)) was scheduled from day 5 through day 9 p.c. Animals were killed on day 10 p.c, and the degree of endometrial decidual growth, plasma levels of oestradiol, progesterone, ACTH and testosterone were determined. Results showed that compared to controls there was a concomitant drop in endometrial decidual growth concurrently with impaired levels of oestradiol and progesterone in diabetic pseudopregnant rats. ACTH and testosterone levels were, however, profoundly elevated. Cyproterone acetate treatment in the diabetic pseudopregnant rat resulted in a simultaneous elevation of oestradiol and progesterone, which eventually helped the endometrial differentiation to decidua in the diabetic pseudopregnant rat parallel to controls. Present experimental data suggest that diabetes-associated impaired endometrial decidualization in the pseudopregnant rat is possibly caused by testosterone-induced oestrogen deficiency.

Simple blood-spot sampling with nested polymerase chain reaction detection for epidemiology studies on Brugia malayi

In the absence of a suitable Brugia malayi antigen detection assay, PCR remains one of the more sensitive alternatives to Giemsa-stained thick blood films for B. malayi detection. The need for refrigerated storage and transportation of blood has limited the use of PCR for large-scale epidemiology studies in remote endemic areas. Here we report simple finger-prick blood-spot collection, a one-tube DNA template extraction method and the development of a B. malayi-specific nested PCR assay. The assay was tested on 145 field samples and was positive for all 30 microscopy-positive samples and for an additional 13 samples which were microscopy-negative.