Influence of Obstructive Sleep Apnea on the Risk of Dental Caries: Insights from a 13-Year Population-Based Retrospective Study

KNOWLEDGE TRANSFER STATEMENT

Obstructive sleep apnea has been proven to have a great negative impact on patients, and the relationship between sleep apnea and dental caries is still inconclusive. Our study shows that patients with sleep apnea and those older than 45 y have a significant risk of dental caries.

Cardiopulmonary Protection for Bilateral Breast Irradiation: A Dosimetric Comparison between Proton and Photon Plans

PURPOSE/OBJECTIVE(S)

Recent advances in cancer treatment improve cancer survivorship. Cardiovascular disease has become the leading cause of non-cancer death in breast cancer survivors. Therefore, risk of cardiopulmonary toxicities during multimodality treatment should be assessed carefully. It remains to be defined the best scenario for proton therapy to confer meaningful cardiovascular protection in the setting of breast irradiation. We hypothesized proton therapy plan provides optimal cardiopulmonary protection during bilateral breast irradiation. The study aimed to compare cardiopulmonary dosimetric parameters of proton and photon radiotherapy plans.

MATERIALS/METHODS

We conducted a retrospective study and patients with bilateral breast cancer indicated for radiotherapy between January 01, 2010 and December 31, 2020 were included. All patients received whole breast or chest wall irradiation with or without regional nodal irradiation. The dose scheme was 50-50.4 Gy in 25-28 fractions. Boost was allowed if patients receiving breast conserving surgery or known risk factors. The dosimetric parameters included planning target volume, mean dose to the heart, the volume of whole lung receiving 5 Gy, 10 Gy, and 20 Gy. For photon therapy, volumetric modulated arc therapy using double partial arc plans was generated with Pinnacle 9.8, Elekta Synergy and tomotherapy helical plan was generated with Tomo Hi-Art planning system. For proton therapy, treatment planning was generated with Ray station 9A. All data was managed using SAS v.9.4 software. Analysis of variance (α = 0.05) was used to compute the dosimetry of different treatment modalities. The statistical significance was considered with a p-value <0.05.

RESULTS

Thirty-one patients with bilateral breast cancer were included, including 12 bilateral breast irradiation patients and 6 bilateral chest wall irradiation patients. The mean dose of heart was 53.0±43.3 cGy in proton therapy while 736.6±225.1 cGy and 869.67±241.0 cGy in Tomotherapy and volumetric modulated arc therapy respectively. The volume of whole lung receiving 5 Gy was 15.4±7.91% in proton therapy while 46.1±10.8% and 46.3±2.5% in Tomotherapy and volumetric modulated arc therapy respectively. The volume of whole lung receiving 20 Gy was 7.7±4.3% in proton therapy while 15.4±5.6% and 19±3.5% in Tomotherapy and volumetric modulated arc therapy respectively. The effects of cardiopulmonary protection were more significant for chest wall irradiation over breast irradiation.

CONCLUSION

Proton radiotherapy provided significant dose reduction for bilateral breast irradiation. The benefit is more significant is patients receiving bilateral chest wall irradiation. Further clinical validations will be warranted to confirm the clinical relevance of the finding.

Roux-en-Y and One-Anastomosis Gastric Bypass Surgery Are Superior to Sleeve Gastrectomy in Lowering Glucose and Cholesterol Levels Independent of Weight Loss: a Propensity-Score Weighting Analysis

BACKGROUND

The superior effects of gastric bypass surgery in preventing cardiovascular diseases compared with sleeve gastrectomy are well-established. However, whether these effects are independent of weight loss is not known.

METHODS

In this retrospective cohort study, we compared the change in cardiometabolic risks of 1073 diabetic patients undergoing Roux-en-Y gastric bypass (RYGB) (n = 265), one-anastomosis gastric bypass (OAGB) (n = 619), and sleeve gastrectomy (SG) (n = 189) with equivalent weight loss from the Min-Shen General Hospital. Propensity score-weighting, multivariate regression, and matching were performed to adjust for baseline differences.

RESULTS

After 12 months, OAGB and, to a lesser extent, RYGB exhibited superior effects on glycemic control compared with SG in patients with equivalent weight loss. The effect was significant in patients with mild-to-modest BMI reduction but diminished in patients with severe BMI reduction. RYGB and OAGB had significantly greater effects in lowering total and low-density lipoprotein cholesterol than SG, regardless of weight loss. The results of matching patients with equivalent weight loss yielded similar results. The longer length of bypassed biliopancreatic (BP) limbs was correlated with a greater decrease in glycemic levels, insulin resistance index, lipids, C-reactive protein (CRP) levels, and creatinine levels in patients receiving RYBG. It was correlated with greater decreases in BMI, fasting insulin, insulin resistance index, and C-reactive protein levels in patients receiving OAGB.

CONCLUSION

Diabetic patients receiving OAGB and RYGB had lower glucose and cholesterol levels compared with SG independent of weight loss. Our results suggest diabetic patients with cardiovascular risk factors such as hypercholesterolemia to receive bypass surgery.

A common East-Asian ALDH2 mutation causes metabolic disorders and the therapeutic effect of ALDH2 activators

Obesity and type 2 diabetes have reached pandemic proportion. ALDH2 (acetaldehyde dehydrogenase 2, mitochondrial) is the key metabolizing enzyme of acetaldehyde and other toxic aldehydes, such as 4-hydroxynonenal. A missense Glu504Lys mutation of the ALDH2 gene is prevalent in 560 million East Asians, resulting in reduced ALDH2 enzymatic activity. We find that male Aldh2 knock-in mice mimicking human Glu504Lys mutation were prone to develop diet-induced obesity, glucose intolerance, insulin resistance, and fatty liver due to reduced adaptive thermogenesis and energy expenditure. We find reduced activity of ALDH2 of the brown adipose tissue from the male Aldh2 homozygous knock-in mice. Proteomic analyses of the brown adipose tissue from the male Aldh2 knock-in mice identifies increased 4-hydroxynonenal-adducted proteins involved in mitochondrial fatty acid oxidation and electron transport chain, leading to markedly decreased fatty acid oxidation rate and mitochondrial respiration of brown adipose tissue, which is essential for adaptive thermogenesis and energy expenditure. AD-9308 is a water-soluble, potent, and highly selective ALDH2 activator. AD-9308 treatment ameliorates diet-induced obesity and fatty liver, and improves glucose homeostasis in both male Aldh2 wild-type and knock-in mice. Our data highlight the therapeutic potential of reducing toxic aldehyde levels by activating ALDH2 for metabolic diseases.

Genome-Wide Association Studies for Albuminuria of Nondiabetic Taiwanese Population

INTRODUCTION

Chronic kidney disease, which is defined by a reduced estimated glomerular filtration rate and albuminuria, imposes a large health burden worldwide. Ethnicity-specific associations are frequently observed in genome-wide association studies (GWAS). This study conducts a GWAS of albuminuria in the nondiabetic population of Taiwan.

METHODS

Nondiabetic individuals aged 30-70 years without a history of cancer were enrolled from the Taiwan Biobank. A total of 6,768 subjects were subjected to a spot urine examination. After quality control using PLINK and imputation using SHAPEIT and IMPUTE2, a total of 3,638,350 single-nucleotide polymorphisms (SNPs) remained for testing. SNPs with a minor allele frequency of less than 0.1% were excluded. Linear regression was used to determine the relationship between SNPs and log urine albumin-to-creatinine ratio.

RESULTS

Six suggestive loci are identified in or near the FCRL3 (p = 2.56 × 10-6), TMEM161 (p = 4.43 × 10-6), EFCAB1 (p = 2.03 × 10-6), ELMOD1 (p = 2.97 × 10-6), RYR3 (p = 1.34 × 10-6), and PIEZO2 (p = 2.19 × 10-7). Genetic variants in the FCRL3 gene that encode a secretory IgA receptor are found to be associated with IgA nephropathy, which can manifest as proteinuria. The PIEZO2 gene encodes a sensor for mechanical forces in mesangial cells and renin-producing cells. Five SNPs with a p-value between 5 × 10-6 and 5 × 10-5 are also identified in five genes that may have a biological role in the development of albuminuria.

CONCLUSION

Five new loci and one known suggestive locus for albuminuria are identified in the nondiabetic Taiwanese population.

Anti-Diabetic Therapy and Heart Failure: Recent Advances in Clinical Evidence and Molecular Mechanism

Diabetic patients have a two- to four-fold increase in the risk of heart failure (HF), and the co-existence of diabetes and HF is associated with poor prognosis. In randomized clinical trials (RCTs), compelling evidence has demonstrated the beneficial effects of sodium-glucose co-transporter-2 inhibitors on HF. The mechanism includes increased glucosuria, restored tubular glomerular feedback with attenuated renin-angiotensin II-aldosterone activation, improved energy utilization, decreased sympathetic tone, improved mitochondria calcium homeostasis, enhanced autophagy, and reduced cardiac inflammation, oxidative stress, and fibrosis. The RCTs demonstrated a neutral effect of the glucagon-like peptide receptor agonist on HF despite its weight-reducing effect, probably due to it possibly increasing the heart rate via increasing cyclic adenosine monophosphate (cAMP). Observational studies supported the markedly beneficial effects of bariatric and metabolic surgery on HF despite no current supporting evidence from RCTs. Bromocriptine can be used to treat peripartum cardiomyopathy by reducing the harmful cleaved prolactin fragments during late pregnancy. Preclinical studies suggest the possible beneficial effect of imeglimin on HF through improving mitochondrial function, but further clinical evidence is needed. Although abundant preclinical and observational studies support the beneficial effects of metformin on HF, there is limited evidence from RCTs. Thiazolidinediones increase the risk of hospitalized HF through increasing renal tubular sodium reabsorption mediated via both the genomic and non-genomic action of PPARγ. RCTs suggest that dipeptidyl peptidase-4 inhibitors, including saxagliptin and possibly alogliptin, may increase the risk of hospitalized HF, probably owing to increased circulating vasoactive peptides, which impair endothelial function, activate sympathetic tones, and cause cardiac remodeling. Observational studies and RCTs have demonstrated the neutral effects of insulin, sulfonylureas, an alpha-glucosidase inhibitor, and lifestyle interventions on HF in diabetic patients.

ER ribosomal-binding protein 1 regulates blood pressure and potassium homeostasis by modulating intracellular renin trafficking

BACKGROUND

Genome-wide association studies (GWASs) have linked RRBP1 (ribosomal-binding protein 1) genetic variants to atherosclerotic cardiovascular diseases and serum lipoprotein levels. However, how RRBP1 regulates blood pressure is unknown.

METHODS

To identify genetic variants associated with blood pressure, we performed a genome-wide linkage analysis with regional fine mapping in the Stanford Asia-Pacific Program for Hypertension and Insulin Resistance (SAPPHIRe) cohort. We further investigated the role of the RRBP1 gene using a transgenic mouse model and a human cell model.

RESULTS

In the SAPPHIRe cohort, we discovered that genetic variants of the RRBP1 gene were associated with blood pressure variation, which was confirmed by other GWASs for blood pressure. Rrbp1- knockout (KO) mice had lower blood pressure and were more likely to die suddenly from severe hyperkalemia caused by phenotypically hyporeninemic hypoaldosteronism than wild-type controls. The survival of Rrbp1-KO mice significantly decreased under high potassium intake due to lethal hyperkalemia-induced arrhythmia and persistent hypoaldosteronism, which could be rescued by fludrocortisone. An immunohistochemical study revealed renin accumulation in the juxtaglomerular cells of Rrbp1-KO mice. In the RRBP1-knockdown Calu-6 cells, a human renin-producing cell line, transmission electron and confocal microscopy revealed that renin was primarily retained in the endoplasmic reticulum and was unable to efficiently target the Golgi apparatus for secretion.

CONCLUSIONS

RRBP1 deficiency in mice caused hyporeninemic hypoaldosteronism, resulting in lower blood pressure, severe hyperkalemia, and sudden cardiac death. In juxtaglomerular cells, deficiency of RRBP1 reduced renin intracellular trafficking from ER to Golgi apparatus. RRBP1 is a brand-new regulator of blood pressure and potassium homeostasis discovered in this study.

A genome-wide association study for melatonin secretion

Melatonin exerts a wide range of effects among various tissues and organs. However, there is currently no study to investigate the genetic determinants of melatonin secretion. Here, we conducted a genome-wide association study (GWAS) for melatonin secretion using morning urine 6-hydroxymelatonin sulfate-to-creatinine ratio (UMCR). We initially enrolled 5000 participants from Taiwan Biobank in this study. After excluding individuals that did not have their urine collected in the morning, those who had history of neurological or psychiatric disorder, and those who failed to pass quality control, association of single nucleotide polymorphisms with log-transformed UMCR adjusted for age, sex and principal components of ancestry were analyzed. A second model additionally adjusted for estimated glomerular filtration rate (eGFR). A total of 2373 participants underwent the genome-wide analysis. Five candidate loci associated with log UMCR (P value ranging from 6.83 × 10−7 to 3.44 × 10−6) encompassing ZFHX3, GALNT15, GALNT13, LDLRAD3 and intergenic between SEPP1 and FLJ32255 were identified. Similar results were yielded with further adjustment for eGFR. Interestingly, the identified genes are associated with circadian behavior, neuronal differentiation, motor disorders, anxiety, and neurodegenerative diseases. We conducted the first GWAS for melatonin secretion and identified five candidate genetic loci associated with melatonin level. Replication and functional studies are needed in the future.

Recurrent umbilical varix rupture with hemoperitoneum: a case report and review of literature

Background

Non-traumatic hemoperitoneum was a rare event with the risk of sudden death. Spontaneous rupture of hepatocellular carcinoma is the most intuitive diagnosis when hemoperitoneum occurs in cirrhotic patients who are not regularly followed up. However, other etiologies of hemoperitoneum, such as intra-abdominal varix rupture, should be kept in mind.

Case presentation

A 44-year-old man with alcoholic liver cirrhosis, Child–Pugh B was sent to our emergency department (ED) because of recurrent abdominal pain and hypovolemic shock. He had similar symptoms one month ago and was diagnosed as hepatocellular carcinoma (HCC) rupture with hemoperitoneum, therefore he underwent trans-arterial embolization (TAE). However, the follow-up magnetic resonance imaging (MRI) showed less possibility of hepatocellular carcinoma. Contrast enhanced abdominal computed tomography (CT) showed possible umbilical vein contrast agent extravasation. Exploratory laparotomy confirmed the diagnosis of rupture umbilical varix with hemoperitoneum.

Conclusion

Although umbilical varix rupture is a rare cause of hemoperitoneum, it should be kept in mind in cirrhotic patients with unexplained hemoperitoneum.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02167-3.

Statewide Efficacy Assessment of Insect Growth Regulators Against Aedes albopictus (Diptera: Culicidae) in Sabah, Malaysia: An Alternative Control Strategy?

The efficacy of three groups of insect growth regulators, namely juvenile hormone mimics (methoprene and pyriproxyfen), chitin synthesis inhibitors (diflubenzuron and novaluron), and molting disruptor (cyromazine) was evaluated for the first time, against Aedes albopictus Skuse (Diptera: Culicidae) larvae from 14 districts in Sabah, Malaysia. The results showed that all field populations of Ae. albopictus were susceptible towards methoprene, pyriproxyfen, diflubenzuron, novaluron, and cyromazine, with resistance ratio values ranging from 0.50-0.90, 0.60-1.00, 0.67-1.17, 0.71-1.29, and 0.74-1.07, respectively. Overall, the efficacy assessment of insect growth regulators in this study showed promising outcomes and they could be further explored as an alternative to conventional insecticides.

Assessment of the susceptibility status of Aedes albopictus (Diptera: Culicidae) from Interior, Sandakan and Tawau divisions of Sabah, Malaysia based on WHO diagnostic doses of larvicides

Susceptibility status of Aedes albopictus (Skuse) sampled from residential areas in Interior, Sandakan and Tawau divisions of Sabah, Malaysia, was evaluated based on the WHOrecommended doses of organochlorine and organophosphate larvicides. To determine susceptibility status, larval bioassays were carried out and post 24-hour mortalities based on WHO resistance classifications were adopted. The results demonstrated that Ae. albopictus larvae were resistant toward 5 out of the 8 larvicides tested. Larvae from all populations were resistant against bromophos, fenitrothion, malathion, temephos and dichlorodiphenyltrichloroethane (DDT), with mortalities ranging from 0.00 to 89.33%. Dieldrin, on the other hand, could induce 100.00% mortalities in all populations, followed by fenthion and chlorpyrifos, with mortalities ranging from 97.33 to 100.00% and 81.33 to 100.00% respectively. Despite most populations exhibiting similitude in their resistance status, larvae from Sandakan exhibited the highest resistance level whereas the lowest level was observed in Keningau. In view of the inadequacy of some larvicides in controlling Ae. albopictus in this study, integrated management such as insecticide rotation or combination of interventions is warranted.

Residual efficacy of deltamethrin applied to foliage against Malaysian Aedes aegypti (L.) and Aedes albopictus (Skuse)

The spraying of insecticide on foliage to provide an insecticidal barrier may serve as part of the vector control measures to combat the increasing threat of Aedes-borne diseases. The effectiveness of insecticide barrier spraying was evaluated by assessing the residual efficacy of deltamethrin sprayed on foliage against Malaysian Ae. aegypti (L.) and Ae. albopictus (Skuse). In this semi-field study, landscape plants grown within the vicinity of the Institute for Medical Research (IMR), Malaysia, were treated with deltamethrin suspension concentrate (SC) with the dosage of 30 mg/m² and 50 mg/m² in three rounds of spraying. Deltamethrin residual activity on treated and untreated leaves was investigated using standard WHO cone bioassays. Wild Aedes populations at both deltamethrin-treated and untreated plant clusters were monitored by ovitrap surveillance. Ovitrap monitoring revealed that the mean number of Ae. albopictus larvae at deltamethrin-treated were significantly lower than the mean number of larvae of the same species at the untreated plant cluster. Cone bioassay results showed that the insecticide remained effective for up to 4 weeks (> 80% mortality), but the insecticide residual activity was affected by rainfall. These results suggest that insecticide barrier spraying is a promising tool and may be used along with other mosquito control tools such as indoor residual spray and space spraying to reduce the dengue burden.

PesTrapp mobile app: A trap setting application for real-time entomological field and laboratory study

Diseases such as malaria, dengue, Zika and chikungunya remain endemic in many countries. Setting and deploying traps to capture the host/vector species are fundamental to understand their density and distributions. Human effort to manage the trap data accurately and timely is an exhaustive endeavour when the study area expands and period prolongs. One stop mobile app to manage and monitor the process of targeted species trapping, from field to laboratory level is still scarce. Toward this end, we developed a new mobile app named "PesTrapp" to acquire the vector density index based on the mobile updates of ovitraps and species information in field and laboratory. This study aimed to highlight the mobile app's development and design, elucidate the practical user experiences of using the app and evaluate the preliminary user assessment of the mobile app. The mobile app was developed using mobile framework and database. User evaluation of the mobile app was based on the adjusted Mobile App Rating Scale and Standardized User Experience Percentile Rank Questionnaire. The process flows of system design and detailed screen layouts were described. The user experiences with and without the app in a project to study Aedes surveillance in six study sites in Selangor, Malaysia were elucidated. The overall mean user evaluation score of the mobile app was 4.0 out of 5 (SD=0.6), reflects its acceptability of the users. The PesTrapp, a one-stop solution, is anticipated to improve the entomological surveillance work processes. This new mobile app can contribute as a tool in the vector control countermeasure strategies.

Who writes dermatology randomized controlled trials? The need to specify the role of medical writers

Medical writers may make major contributions to the preparation of a manuscript, but are not listed as authors. We assessed the prevalence, affiliation and role of medical writers in dermatology randomized controlled trials (RCTs) published in 2019 in the top 7 medical and top 10 dermatology journals. Medical writers were identified in 39/83 trials (47%), all of which were exclusively industry-funded trials (39/47, prevalence 83%). Most studies stated their role as 'medical writing support' and/or 'editorial assistance' (35/39, 90%), but when more information was provided, four studies specified first draft preparation (50% of RCTs in general medical and 1.3% of RCTs in dermatology journals). Medical writers are common in dermatology trials but their role is often vaguely stated. In April 2020 the British Journal or Dermatology and Clinical and Experimental Dermatology adopted CRediT (Contributor Roles Taxonomy), which describes contributions of authors and may help clarify who writes trial manuscripts.

The status and outcomes of registered clinical trials for Janus kinase inhibitors in alopecia areata: are unpublished trials being overlooked?

Recent meta-analyses of Janus kinase (JAK) inhibitors in alopecia areata (AA) have excluded trial registries and may thus be subject to publication bias. This study assessed the potential for evidence selection bias and provides an overview of JAK inhibitor trials in AA. A broad search strategy of ClinicalTrials.gov was performed for AA. We also recorded whether results were published on PubMed. There were 26 trials identified, of which 9 were ongoing (mostly oral JAK inhibitors: 8 studies; 89%). Of completed/terminated trials, 4/17 (24%) had terminated prematurely, citing 'inefficacy/futility' or 'sponsor decision'. These were all topical JAK inhibitor trials (4/8, 50% termination rate), with a 0% termination rate (0/9) for oral JAK inhibitor trials. We conclude that topical JAK inhibitors may be less efficacious than has been apparent in the literature to date, with 50% of trials having terminated due to inefficacy/futility or sponsor decision and only one topical JAK inhibitor trial ongoing.

The role of breath hold intensity modulated proton therapy for a case of left-sided breast cancer with IMN involvement. How protons compare with other conformal techniques?

Purpose

To evaluate the dosimetric impact of four different radiotherapy techniques for a case of left-sided breast cancer with Internal Mammary lymph Nodes (IMN) involvement.

Materials and methods

To identify the best radiotherapy technique for this patient, four methods were compared: 3D Conformal Radiotherapy (3D-CRT), Volumetric Modulated Arc Therapy (VMAT), Tomotherapy (TOMO) and Intensity Modulated Proton Therapy (IMPT). Patient was treated using deep inspiration breath-hold (DIBH) technique. Prescribed dose was 40.05y in 15 fractions. Plan evaluation was performed on target coverage and dose to the organs-at-risk (OARs) using 3D-CRT as a baseline.

Results

TOMO has the most ideal Conformity Index (CI) at 1.139, followed by IMPT at 1.158, VMAT at 0.765, and 3D-CRT at 0.685. Using 3D-CRT as a baseline, VMAT, TOMO and IMPT all showed improved dose coverage. IMPT has the best dose coverage. TOMO has the most ideal homogeneity index (HI) and Conformity Number (CN). Mean heart dose (MHD) is lowest for IMPT at 0.55 Gy and highest for VMAT at 4.79 Gy. V20Gy of left lung is the lowest for IMPT at 11.11%, compared to 17.53% for TOMO, 18.19% for VMAT and 33.33% for 3D-CRT. V5Gy for the contralateral breast ranges from 0.01% in IMPT to 72.32% in TOMO.

Conclusion

3D-CRT compromising target coverage but achieving good OAR sparing for the contralateral right breast, left lung and right lung. Overall, IMPT performed best in terms of target coverage and OAR-sparing. Protons delivered superior target dose coverage and sparing of normal structures for this patient. As dose value parameters are expected to correlate with acute and chronic toxicities, proton therapy should be given due consideration as the preferred technique for the treatment of left-sided breast cancers with IMN involvement. Further studies with more patients can be done to evaluate the effectiveness of proton therapy on acute and chronic toxicities.

Clinical features and prognosis of patients with idiopathic pulmonary fibrosis and chronic obstructive pulmonary disease

<sec> <title>BACKGROUND</title> Idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) share common risk factors. They could therefore be expressed in a single patient. However, the prevalence, clinical characteristics and prognosis of individuals with comorbid IPF and COPD are not known. </sec> <sec> <title>METHOD</title> From 2003 to 2007, the Korean Interstitial Lung Disease Study Group created a register for idiopathic interstitial pneumonia using 2002 ATS/ERS (American Thoracic Society/European Respiratory Society) criteria. Of the 1546 IPF patients assessed, 143 had decreased lung function consistent with COPD (IPF-COPD). COPD was diagnosed based on age (≥40 years) and pulmonary function (forced expiratory volume in 1 sec [FEV₁]/forced vital capacity [FVC] ratio < 0.7). </sec> <sec> <title>RESULTS</title> The median age of the IPF-COPD group was 71.0 years (interquartile range 66.0-76.0); most patients were male (88.1%). FVC (%) was significantly higher in the IPF-COPD group; however, FEV₁ (%) was significantly lower in the IPF-COPD group (P < 0.001). Diffusing capacity of the lung for carbon monoxide (DL_CO) was not significantly different between the two groups. In survival analysis, age and FVC (%), but not COPD, were significantly associated with prognosis (respectively P = 0.003, 0.001 and 0.401). COPD severity was also not related to prognosis (P = 0.935). </sec> <sec> <title>CONCLUSION</title> The prevalence of IPF-COPD was estimated to be ∼9.2% among all IPF patients; prognosis of patients with IPF-COPD was not worse than those with IPF alone. </sec>.

Status of pyrethroid resistance in Aedes (Stegomyia) aegypti (Linneaus) from dengue hotspots in Klang Valley, Malaysia

The continued absence of an effective and safe tetravalent dengue vaccine and the lack of specific anti-viral treatment have made mosquito vector control using chemical insecticides as the mainstream for dengue prevention and control. However, the long-term use of chemical insecticides may induce resistance. Hence detection of insecticide resistance in dengue vectors is crucially important in ensuring the insecticide-based intervention in dengue control program is still effective and reliable. In this study, the susceptibility status of Aedes aegypti from five selected dengue hotspots in Klang Valley, Malaysia against pyrethroids was determined by employing the World Health Organization (WHO) protocol of adult bioassay. Four types of pyrethroids were tested against adult female Aedes aegypti to determine the knockdown rate, post 24-h adult mortality and resistance ratio. All field-collected Aedes aegypti strains were resistant to the four pyrethroids tested, except for the Taman Sungai Jelok (TSJ) strain. Permethrin exhibited the lowest knockdown rate against Aedes aegypti, followed by deltamethrin, cyfluthrin and lambda-cyhalothrin. This present study indicated the widespread of pyrethroid resistance in Aedes aegypti in Klang Valley, indicating the needs of implementing alternative measures in vector control program. The data in this study can be utilised as an input for insecticide resistance management of Aedes aegypti in Malaysia.

A preliminary proteomic study of permethrin resistant and susceptible Aedes aegypti (L.)

The mechanism of insecticide resistance is traditionally attributed to detoxification enzymes, target site alteration, decreased penetration of insecticides and behavioural resistance. Other form of mechanisms, such as the role of protein(s) in resistance is unknown. In the present study, the protein profiling of both IMR-PSS strain (permethrin-selected) and IMR-LS strain (laboratory-susceptible) 24 hours post exposure period to permethrin was carried out via 1D-gel electrophoresis and liquid chromatography mass spectrometry (LC-MS/ MS). The bands which appeared in the gel of 1D-electrophoresis revealed an abundance of proteins. The band pattern of both strains looked macroscopically alike and differed only in band intensity. However, LC-MS/MS analysis revealed that the IMR-PSS strain produced extra 388 peptides that were not found in the IMR-LS strain, indicating that IMR-PSS strain reacted differently from IMR-LS strain as a result of persistent exposure to permethrin. Since the complex banding patterns of 1D-gel electrophoresis were difficult to interpret the significance of the protein difference between IMR-PSS and IMR-LS strain, hence LC-MS/MS analysis is ideally suited for better protein resolution and thus will allow more in-depth comparison of the complex pattern. The findings here provide the first preliminary evidence that insecticide resistance in mosquito induces up regulation of proteins that may be protective to mosquitoes against insecticide and proteins could be another mechanism that contributes to development of resistance.

Adulticide Resistance Status of Aedes albopictus (Diptera: Culicidae) in Sabah, Malaysia: A Statewide Assessment

Resistance status of Aedes albopictus (Diptera: Culicidae) collected from Sabah, East Malaysia, was evaluated against four major classes of adulticides, namely pyrethroid, carbamate, organochlorine, and organophosphate. Adult bioassays conforming to WHO standard protocols were conducted to assess knockdown and mortality rates of Ae. albopictus. Among tested pyrethroid adulticides, only cyfluthrin, lambda-cyaholthrin, and deltamethrin were able to inflict total knockdown. The other adulticide classes mostly failed to cause any knockdown; the highest knockdown rate was only 18.33% for propoxur. With regards to mortality rate, Ae. albopictus was unanimously susceptible toward all pyrethroids, dieldrin, and malathion, but exhibited resistance toward bendiocarb, propoxur, dichlorodiphenyltrichloroethane, and fenitrothion. Additionally, correlation analysis demonstrated cross-resistance between bendiocarb and propoxur, and malathion and propoxur. In conclusion, this study has disclosed that pyrethroids are still generally effective for Aedes control in Sabah, Malaysia. The susceptibility status of Ae. albopictus against pyrethroids in descending order was cyfluthrin > lambda-cyhalothrin > deltamethrin > etofenprox > permethrin.

Pteridine fluorescence in age-determination of immature Chrysomya megacephala (Fabricius) and Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae)

In the practice of forensic entomology, the chronological age of the maggots retrieved from the cadaver is used to determine the minimum post-mortem interval (mPMI) i.e. minimum time of death. The conventional method of aging the maggots is based on measuring the growth rate of these maggots. Although effective, the constraint associated with conventional method necessitates the development of new age determination method, such as pteridine determination. Pteridine, a by-product of protein metabolism in insects is known to correlate with the age of a variety of dipterans. A number of studies were conducted on aging the adults of forensically important flies. In this study, pteridine was extracted from Chrysomya megacephala and Chrysomya rufifacies maggots of known age using established methods and determined by measuring the fluorescence at excitation of 330nm and the emissions between 350nm and 600nm. Results exhibited significant positive linear relationships between the pteridine accumulations and age of the fly immature. Pteridine determination is a potential new age determination tool that can be used to determine mPMI.

Active Transport of Membrane Components by Self-Organization of the Min Proteins

Heterogeneous distribution of components in the biological membrane is critical in the process of cell polarization. However, little is known about the mechanisms that can generate and maintain the heterogeneous distribution of the membrane components. Here, we report that the propagating wave patterns of the bacterial Min proteins can impose steric pressure on the membrane, resulting in transport and directional accumulation of the component in the membrane. Therefore, the membrane component waves represent transport of the component in the membrane that is caused by the steric pressure gradient induced by the differential levels of binding and dissociation of the Min proteins in the propagating waves on the membrane surface. The diffusivity, majorly influenced by the membrane anchor of the component, and the repulsed ability, majorly influenced by the steric property of the membrane component, determine the differential spatial distribution of the membrane component. Thus, transportation of the membrane component by the Min proteins follows a simple physical principle, which resembles a linear peristaltic pumping process, to selectively segregate and maintain heterogeneous distribution of materials in the membrane. VIDEO ABSTRACT.

Bioefficacy Evaluation of Commercial Mosquito Coils Containing Metofluthrin, d-Allethrin, d-Trans Allethrin, and Prallethrin Against Aedes albopictus (Diptera: Culicidae) in Malaysia

The bioefficacy of commercial mosquito coils containing four different active ingredients, namely metofluthrin, d-allethrin, d-trans allethrin, and prallethrin against Aedes albopictus (Skuse) (Diptera: Culicidae) from 10 states in Malaysia, was evaluated using the glass chamber method. In this study, Ae. albopictus exhibited various knockdown rates (50% knockdown time, KT50), ranging from 2.50 to 5.00 min, 2.50 to 7.00 min, 3.00 to 8.00 min, and 5.00 to 17.00 min for metofluthrin, d-trans allethrin, d-allethrin, and prallethrin, respectively. Overall, all strains of Ae. albopictus were most susceptible to metofluthrin, with mortality rates >80%. On the other hand, mortality rates ranging from 5.0 to 100% were observed from all populations exposed to d-trans allethrin, d-allethrin, and prallethrin. In addition, significant correlations between KT50 of metofluthrin and d-allethrin (r = 0.758, P = 0.011), metofluthrin and prallethrin (r = 0.676, P = 0.032), d-allethrin and d-trans allethrin (r = 0.832, P = 0.003), d-allethrin and prallethrin (r = 0.921, P = 0.000), and d-trans allethrin with prallethrin (r = 0.941, P = 0.000) were detected, suggesting some levels of cross-resistance within the pyrethroid insecticides. This study demonstrated that metofluthrin can induce high insecticidal activity in Ae. albopictus in Malaysia, followed by d-trans allethrin, d-allethrin, and prallethrin.

Early development of de novo hepatocellular carcinoma after direct-acting agent therapy: Comparison with pegylated interferon-based therapy in chronic hepatitis C patients

Patients with chronic hepatitis C who achieve a sustained viral response after pegylated interferon therapy have a reduced risk of hepatocellular carcinoma, but the risk after treatment with direct-acting antivirals is unclear. We compared the rates of early development of hepatocellular carcinoma after direct-acting antivirals and after pegylated interferon therapy. We retrospectively analysed 785 patients with chronic hepatitis C who had no history of hepatocellular carcinoma (211 treated with pegylated interferon, 574 with direct-acting antivirals) and were followed up for at least 24 weeks after antiviral treatment. De novo hepatocellular carcinoma developed in 6 of 574 patients receiving direct-acting antivirals and in 1 of 211 patients receiving pegylated interferon. The cumulative incidence of early hepatocellular carcinoma development did not differ between the treatment groups either for the whole cohort (1.05% vs 0.47%, P = .298) or for those patients with Child-Pugh Class A cirrhosis (3.73% vs 2.94%, P = .827). Multivariate analysis indicated that alpha-fetoprotein level >9.5 ng/mL at the time of end-of-treatment response was the only independent risk factor for early development of hepatocellular carcinoma in all patients (P < .0001, hazard ratio 176.174, 95% confidence interval 10.768-2882.473) and in patients treated with direct-acting agents (P < .0001, hazard ratio 128.402, 95% confidence interval 8.417-1958.680). In conclusion, the rate of early development of hepatocellular carcinoma did not differ between patients treated with pegylated interferon and those treated with direct-acting antivirals and was associated with the serum alpha-fetoprotein level at the time of end-of-treatment response.

Organophosphate and Organochlorine Resistance in Larval Stage of Aedes albopictus (Diptera: Culicidae) in Sabah, Malaysia

The present study aims to investigate the susceptibility status of Aedes albopictus (Skuse) collected from residential areas in Sabah, Malaysia towards eight WHO-recommended dosages of larvicides representing the classes of organophosphates and organochlorines. Field and reference strains of Ae. albopictus larvae were bioassayed in accordance to WHO standard methods using diagnostic dosages of bromophos, malathion, fenthion, fenitrothion, temephos, chlorpyrifos, dichlorodiphenyltrichloroethane (DDT), and dieldrin. The results revealed that Ae. albopictus was resistant (mortality < 90%) towards malathion, temephos, and DDT. In addition, most of the Ae. albopictus strains exhibited a wide range of susceptibilities against bromophos, with mortality ranged from 49.33 to 93.33%. On the contrary, only dieldrin was able to induce 100% mortality against all strains of Ae. albopictus. Tolerance to fenitrothion, fenthion, and chlorpyrifos, with mortality ranging from 81.33 to 97.33%, was also observed in this study.

Ovitrap surveillance in Sarawak, Malaysia: A comprehensive study

Tropical Infectious Diseases Research and Education Centre (TIDREC), University of Malaya, 50603 Kuala Lumpur, Malaysia This study reports the distribution and abundance of Aedes by using ovitrap surveillance and aims to provide the most recent information on dengue vector distribution in Sarawak State, Malaysia. The ovitrap index (OI) of Aedes larvae was found highest in urban residential area (mean OI = 90.97%), followed by suburban (69.70%), rural (65.45%) and remote (52.63%) residential areas. The mean number of Aedes larvae per ovitrap was also found to be significantly highest in urban residential area (26.47 ± 1.62) compared to other type of residential areas (p<0.05). Interestingly, no Aedes aegypti was observed in this study, but two species of Armigeres were found co-breeding with Ae. albopictus. This study reveals that Ae. albopictus is the dominant dengue vector in Sarawak State and all the surveyed residential areas are in risk of dengue transmission with OI > 10.

Comparative Efficacy of Commercial Mosquito Coils Against Aedes aegypti (Diptera: Culicidae) in Malaysia: A Nationwide Report

This study was conducted using the glass chamber method to determine the susceptibility status of the dengue vector, Aedes aegypti (L.) from 11 states in Malaysia to commercial mosquito coils containing four different active ingredients, namely metofluthrin, d-allethrin, d-trans allethrin, and prallethrin. Aedes aegypti exhibited various knockdown rates, ranging from 14.44% to 100.00%, 0.00% to 61.67%, 0.00% to 90.00%, and 0.00% to 13.33% for metofluthrin, d-allethrin, d-trans allethrin, and prallethrin, respectively. Overall, mortality rates ranging from 0.00% to 78.33% were also observed among all populations. Additionally, significant associations were detected between the knockdown rates of metofluthrin and d-allethrin, and between metofluthrin and d-trans allethrin, suggesting the occurrence of cross-resistance within pyrethroid insecticides. Overall, this study revealed low insecticidal activity of mosquito coils against Ae. aegypti populations in Malaysia, and consequently may provide minimal personal protection against mosquito bites.

Simulated field study on the efficacy of the thermal application of a synergized pyrethroid formulation against Aedes aegypti (Linn.) and Culex quinquefasciatus Say

Thermal application of a synergized pyrethroid formulation containing 0.8% w/w sbioallethrin, 18.7% w/w permethrin and 16.8% w/w piperonyl butoxide was performed to evaluate its efficacy against adult and larva of Aedes aegypti and Culex quinquefasciatus. Three cages each containing 15 mosquitoes and paper cups each containing 25 larvae in 250 ml of water were deployed at each test point between 3 and 20 feet. The formulation was diluted (formulation:water) 1:33, 1:50 and 1:100, respectively, and applied using a thermal fogger. Sixty minutes post spraying, the adult knock down rate of Ae. aegypti and Cx. quinquefasciatus at a maximum distance of 15 feet using all dilution ratios ranged from 96.67 - 100% and 43.33 - 100%, respectively. More than 70.00% adult mortalities were recorded for both mosquito species at the distance between 3 feet and 15 feet 24 hours post spraying. In contrast, complete larval mortalities of Ae. aegypti were obtained at a maximum distance of 10 feet with dilution ratio of 1:33, while more than 80.00% larval mortalities were observed for Cx. quinquefasciatus at similar maximum distance using all dilution ratios. These results showed that thermal application using synergized pyrethroid formulation was effective against both mosquito species tested especially the adult stage.

Biting behaviour of medically important mosquitoes (Diptera: Culicidae) in Peninsular Malaysia

Human-landing catch (HLC) technique was undertaken in nine selected study sites within Peninsular Malaysia to determine the biting cycle of Aedes, Armigeres, Culex, and Mansonia mosquitoes. HLC was conducted 24 hours on three different nights in a duration of one week at each study site. Aedes albopictus were found in all study sites with bimodal biting cycle, whereas the biting peak of Aedes butleri was recorded between 1600 and 1900 hr. For Armigeres, five study sites demonstrated similar biting peak hour (1900 - 2000 hr) for Ar. kesseli four study sites showed biting peak at 1800 - 1900 hr for Ar. subalbatus. Culex quinquefasciatus was collected from all study sites except in Sungai Penchala with its biting activity beginning from 1900 hr. Both Mansonia annulifera and Mansonia uniformis captured in two different study sites showed similar biting peaks (1500 - 1600 hr). It is recommended that vector control activities be carried out at dusk as almost all mosquito species captured started their biting activities at that time.

Management of traumatic patellar dislocation in a regional hospital in Hong Kong

INTRODUCTION

The role of surgery for acute patellar dislocation without osteochondral fracture is controversial. The aim of this study was to report the short-term results of management of patellar dislocation in our institute.

METHODS

Patients who were seen in our institution with patella dislocation from January 2011 to April 2014 were managed according to a standardised management algorithm. Pretreatment and 1-year post-treatment International Knee Documentation Committee score, Tegner activity level scale score, and presence of apprehension sign were analysed.

RESULTS

A total of 41 patients were studied of whom 20 were first-time dislocators and 21 were recurrent dislocators. Among the first-time dislocators, there was a significant difference between patients who received conservative treatment versus surgical management. The conservative treatment group had a 33% recurrent dislocation rate, whereas there were no recurrent dislocations in the surgery group. There was no difference in Tegner activity level scale score or apprehension sign before and 1 year after treatment, however. Among the recurrent dislocators, there was a significant difference between those who received conservative treatment and those who underwent surgery. The recurrent dislocation rate was 71% in the conservative treatment group versus 0% in the surgery group. There was also significant improvement in International Knee Documentation Committee score from 67.7 to 80.0 (P=0.02), and of apprehension sign from 62% to 0% (P<0.01).

CONCLUSIONS

A management algorithm for patellar dislocation is described. Surgery is preferable to conservative treatment in patients who have recurrent patellar dislocation, and may also be preferable for those who have an acute dislocation.

Repellency effects of an ozone-producing air purifier against medically important insect vectors

An indoor ozone-producing air purifier was evaluated for its repellency effects on Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, Musca domestica and Periplaneta americana adults using a modified tunnel cage. The first set of testing consisted of both bait and the air purifier, whereas only bait was offered in the second testing set. The highest percent repellency was recorded among Cx. quinquefasciatus (83.23%) while Ae. aegypti (68.56%) was the least repelled by the air purifier tested. No mortality was observed in all testings. These results illustrated the potential use of the ozone-producing air purifier as a personal protection insect repellent device in premises. Nevertheless, in order to prevent dengue infection which is transmitted by both Ae. aegypti and Ae. albopictus, ozone-producing air purifier should be utilized concurrently with other vector control methods.

Detection of Wolbachia from field collected Aedes albopictus Skuse in Malaysia

Background & objectives:

Wolbachia-based vector control strategies have been proposed as a mean to augment the existing measures for controlling dengue vector. Prior to utilizing Wolbachia in novel vector control strategies, it is crucial to understand the Wolbachia-mosquito interactions. Many studies have only focused on the prevalence of Wolbachia in female Aedes albopictus with lack of attention on Wolbachia infection on the male Ae. albopictus which also affects the effective expression of Wolbachia induced- cytoplasmic incompatibility (CI). In this study, field surveys were conducted to screen for the infection status of Wolbachia in female and male Ae. albopictus from various habitats including housing areas, islands and seashore.

Methods:

Adult Ae. albopictus (n=104) were collected using human landing catches and hand aspirator. Standard ovitraps were also set in the selected areas for five days and the larvae were identified to species level. All the collected Ae. albopictus were screened for the presence of Wolbachia using multiplex polymerase chain reaction (PCR) and gene sequencing of Wolbachia surface protein (wsp) gene.

Results:

A 100 per cent positivity of Wolbachia infection was observed for individual Ae. albopictus screened. For pooled mosquitoes, 73 of the 76 pools (female) and 83 of the 87 pools (male) were positive with Wolbachia infection. The wsp gene sequence of the Wolbachia strain isolated from individual and pooled mosquitoes showed a 100 per cent homology with Wolbachia sp. of Ae. albopictus isolated from various geographical regions. Phylogenetic analysis based on wsp gene fragments showed that the isolates were clustered into groups A and B, respectively.

Interpretation & conclusions:

The results indicated that Wolbachia infection was widespread in Ae. albopictus population both in female and male Ae. albopictus. All the infected females were superinfected with both A and B strains while the infected males showed a combination of superinfection of A and B strains and single infection of B strain.

Effects of vitamin B fortified sucrose solution on the longevity and reproductive potentials of laboratory-bred Culex quinquefasciatus Say adult

Laboratory colonised mosquitoes are usually maintained on vitamin B complex fortified sucrose solution, however only few studies were conducted to evaluate the effects of such practice. This study aimed to determine the effects of different concentrations of sucrose solution fortified with and without 1% vitamin B complex on the longevity and reproductive potential of adult female of a local strain of Culex quinquefasciatus Say. Two arms of studies were carried out separately and each arm was triplicated. In one arm, concentrations of sucrose solution at 0%, 1%, 3%, 5% and 10% fortified with 1% Vitamin B complex were fed to the mosquitoes, while in the other arm, similar sucrose concentrations were used but without 1% vitamin B complex. Adult Cx. quinquefasciatus maintained on 5% sucrose solution fortified with 1% vitamin B complex exhibited significant extended vitality and longevity in stimulating ovarian development, compared with other vitamin fortified sucrose concentrations (p<0.05). The vitality and longevity of F0 and F1 males were 76.67±2.19 days and 57.67±8.19 days respectively. The F0 females survived the longest duration of 107.67±5.61 days and the F1 females survived 90.67±12.47 days with higher number of eggs laid, i.e. 1427.67±62.89 eggs at a higher hatchability rate of 57.05±8.39% or 814.49 eggs hatched. Thus, 5% sucrose solution fortified with 1% Vitamin B complex should be used to produce colonies of homogenous mosquitoes as this exerts positive biological effects on laboratory-bred Cx. quinquefasciatus.

Similar vertical transmission rates of dengue and chikungunya viruses in a transgenic and a non-transformed Aedes aegypti (L.) laboratory strain

The increase of the burden of dengue and chikungunya and the relative failure of traditional vector control strategies have highlighted the need to develop new control methods. RIDL-SIT, a vector control method based on the release of engineered male mosquitoes, has shown promising results from field trials conducted in the Cayman Islands and Brazil. In large scale use, a small proportion of females might be released along with the males. Such females are potential virus vectors; here we investigate the vertical transmission of dengue and chikungunya of homozygous OX513A females.We provided females of OX513A-My1 and a wild type comparator strain with blood meals artificially infected with dengue serotype 1, 2, 3, 4 or chikungunya viruses. For 14 days post-feeding, eggs laid by females were collected. Larvae and their mothers were first tested by qRT-PCR, then by inoculation on cell cultures to search for infectious viral particles. We found no significant difference between the minimum infection rate of OX513A-My1 and wild type females. We also discussed the potential number of females being released, a fraction of the female wild population. Consequently, we conclude that there are no evidence that OX513A-My females, if released into the environment, would cause more harm than their wild counterparts.

Quantitative Proteomics Analysis Reveals the Min System of Escherichia coli Modulates Reversible Protein Association with the Inner Membrane

The Min system of Escherichia coli mediates placement of the division septum at the midcell. It oscillates from pole to pole to establish a concentration gradient of the division inhibition that is high at the poles but low at the midcell; the cell middle thereby becomes the most favorable site for division. Although Min oscillation is well studied from molecular and biophysical perspectives, it is still an enigma as to whether such a continuous, energy-consuming, and organized movement of the Min proteins would affect cellular processes other than the division site selection. To tackle this question, we compared the inner membrane proteome of the wild-type and Δmin strains using a quantitative approach. Forty proteins that showed differential abundance on the inner membrane of the mutant cells were identified and defined as proteins of interest (POIs). More than half of the POIs were peripheral membrane proteins, suggesting that the Min system affects mainly reversible protein association with the inner membrane. In addition, 6 out of 10 selected POIs directly interacted with at least one of the Min proteins, confirming the correlation between POIs and the Min system.Further analysis revealed a functional relationship between metabolism and the Min system. Metabolic enzymes accounted for 45% of the POIs, and there was a change of metabolites in the related reactions. We hypothesize that the Min system could alter the membrane location of proteins to modulate their enzymatic activity. Thus, the metabolic modulation in the Δmin mutant is likely an adaptive phenotype in cells of abnormal size and chromosome number due to an imbalanced abundance of proteins on the inner membrane. Taken together, the current work reports novel interactions of the Min system and reveals a global physiological impact of the Min system in addition to the division site placement.

Evaluation of insect growth regulators, temephos and Bacillus thuringiensis israelensis against Aedes aegypti (L) in plastic containers

The residual activities of 5 insect growth regulators (IGRs) were studied and compared to operational dosage of temephos (1 mg/L) and Bacillus thuringiensis israelensis (Bti) (0.008 mg/L). The IGRs, temephos and Bti were applied into plastic containers containing 5 litres of water. Thirty Aedes aegypti larvae were added into each container weekly. Efficacy of these IGRs were evaluated for effective duration of each dosage and the percentage of emergence inhibition (EI). An end-point of EI/mortality ≥ 50% was considered to be effective. Pyriproxyfen possessed the longest residual activity in both indoor (43 weeks) and outdoor (26 weeks) conditions, followed by temephos (26 weeks in indoor and 16 weeks in outdoor). Although the residual activity of Bti in indoor lasted 8 weeks which was longer than cyromazine and diflubenzuron; however, it was least effective in outdoor which only lasted 2 weeks. This study revealed that pyriproxyfen possessed good residual effect among test IGRs compared to temephos and Bti. The use of IGRs can be an alternative long-term control measure in stagnant water body.

ABSENCE OF AEDES AEGYPTI (L.) ON AN ECOLOGICAL ISLAND: COMPETITIVE EXCLUSION?

Ovitrap surveillance was conducted in 2012 and 2006 in Malay and Aboriginal Villages on Carey Island. In each village, standard ovitraps were placed indoors and outdoors at randomly selected houses/locations. All L3 larvae recovered were identified up to species level. Results demonstrated that only larvae of Aedes albopictus were found in all the positive ovitraps placed indoors and outdoors. In 2012, a high ovitrap index (OI) of 66.7% indoor and 84.0% outdoor in the Malay Village; and 62.5% indoor and 88.0% outdoor in Aboriginal Village with an apparent absence of Aedes aegypti. In 2006, a 100% OI was recorded in all ovitraps set indoors and outdoors in both villages.

TEMPORAL CHANGES OF AEDES AND ARMIGERES POPULATIONS IN SUBURBAN AND FORESTED AREAS IN MALAYSIA

Surveillance of mosquitoes and their distribution in association with rainfall, relative humidity, and temperature were conducted in selected suburban and forested areas, namely, Sungai Penchala (Kuala Lumpur) and Taman Alam (Selangor) for 12 months. Armigeres kesseli was the most abundant species in Sungai Penchala while Aedes butleri was the most dominant species in Taman Alam. A positive correlation between mosquito distribution and rainfall was observed in selected mosquito species in Sungai Penchala (Armigeres kesseli, r = 0.75; Armigeres subalbatus, r = 0.62; and Aedes albopictus, r = 0.65) and Taman Alam (Armigeres sp, r = 0.59; Ae. butleri, r = 0.85; and Ae. albopictus, r = 0.62). However, no significant cor- relation was found either between selected mosquito species in both study areas and relative humidity or temperature. Results obtained suggested that vector control programs to be conducted based on temporal distribution of vectors in order to achieve beneficial outcomes with effective costing.

Evaluation of Sumithion L-40 against Aedes aegypti (L.) and Aedes albopictus Skuse

Space spraying of chemical insecticides is still an important mean of controlling Aedes mosquitoes and dengue transmission. For this purpose, the bioefficacy of space-sprayed chemical insecticide should be evaluated from time to time. A simulation field trial was conducted outdoor in an open field and indoor in unoccupied flat units in Kuala Lumpur, to evaluate the adulticidal and larvicidal effects of Sumithion L-40, a ULV formulation of fenitrothion. A thermal fogger with a discharge rate of 240 ml/min was used to disperse Sumithion L-40 at 3 different dosages (350 ml/ha, 500 ml/ha, 750 ml/ha) against lab-bred larvae and adult female Aedes aegypti and Aedes albopictus. An average of more than 80% adult mortality was achieved for outdoor space spray, and 100% adult mortality for indoor space spray, in all tested dosages. Outdoor larvicidal effect was noted up to 14 days and 7 days at a dosage of 500 and 750 ml/ha for Ae. aegypti and Ae. albopictus, respectively. Indoor larvicidal effect was up to 21 days (500 ml/ha) and 14 days (750 ml/ha), respectively, after spraying with larval mortality > 50% against Ae. aegypti. This study concluded that the effective dosage of Sumithion L-40 thermally applied against adult Ae. aegypti and Ae. albopictus indoor and outdoor is 500 and 750 ml/ha. Based on these dosages, effective indoor spray volume is 0.4 - 0.6 ml/m³. Additional indoor and outdoor larvicidal effect will be observed at these application dosages, in addition to adult mortality.

Surveillance of Aedes albopictus Skuse breeding preference in selected dengue outbreak localities, peninsular Malaysia

Entomological surveillance was conducted in order to determine the abundance and to evaluate any changes of biological vectors or ecology, especially in the dengue outbreak areas. The abundance and breeding preference of Aedes albopictus and Aedes aegypti were conducted in selected dengue outbreak localities in three states of peninsular Malaysia namely Selangor, Federal Territory of Kuala Lumpur, and Penang Island using ovitraps and larval survey method. It was determined that Ae. albopictus was predominant in most of the localities and found to breed more outdoor than indoor. A wide range of breeding foci were recorded in this study. It was also determined that ovitrap method was more effective to detect the presence of Aedes mosquitoes when the larval survey was at low rate of infestation. The abundance of Ae. albopictus in dengue outbreak localities emphasis that the vector control programme should also target this species together with the primary dengue vector, Ae. aegypti.

Biochemical characterization and structural analysis of a bifunctional cellulase/xylanase from Clostridium thermocellum

We expressed an active form of CtCel5E (a bifunctional cellulase/xylanase from Clostridium thermocellum), performed biochemical characterization, and determined its apo- and ligand-bound crystal structures. From the structures, Asn-93, His-168, His-169, Asn-208, Trp-347, and Asn-349 were shown to provide hydrogen-bonding/hydrophobic interactions with both ligands. Compared with the structures of TmCel5A, a bifunctional cellulase/mannanase homolog from Thermotoga maritima, a flexible loop region in CtCel5E is the key for discriminating substrates. Moreover, site-directed mutagenesis data confirmed that His-168 is essential for xylanase activity, and His-169 is more important for xylanase activity, whereas Asn-93, Asn-208, Tyr-270, Trp-347, and Asn-349 are critical for both activities. In contrast, F267A improves enzyme activities.

Eco-virological survey of Aedes mosquito larvae in selected dengue outbreak areas in Malaysia

BACKGROUND & OBJECTIVESI: Transovarial transmission of dengue virus in the Aedes vectors is now a well-documented phenomenon reported from many parts of the endemic areas in the world, which played an important role in initiating and maintaining the outbreak in human populations. This study investigated the factors affecting breeding habitats and the relationship with transovarial dengue virus in larvae of Aedes aegypti and Ae. albopictus.

METHODS

Larval surveillance was conducted in dengue outbreak areas in Malaysia from 2008 until 2009. Sampling was carried out based on habitat type, water condition (substrate type), canopy coverage, temperature and pH at breeding habitats. RT-PCR was performed to detect presence of transovarial dengue virus in larvae collected in the study areas.

RESULTS

A total of 789 breeding habitats were identified during this study and the majority of these breeding sites were plastic containers (57.46%). Aedes albopictus dominated most of the water condition surveyed, while Ae. aegypti indicated preference toward habitats with clear water. Aedes aegypti was selective in selecting ovipositional sites compared to Ae. albopictus where shaded areas were shown to be the most preferred. From a total of 363 mosquito larvae pools, 23 (6.3%) pools were positive for dengue virus where 18 of them were from Ae. albopictus and five were from Ae. aegypti mosquito larvae pools.

INTERPRETATION & CONCLUSION

This study indicated the presence of transovarial transmission of dengue virus in immature Ae. aegypti and Ae. albopictus in the field. This study also showed that combination of water conditions, canopy coverage, temperature and pH of breeding habitats were the factors affecting the larval population. The study suggested that larval survey programme could serve as a tool not only to monitor the local dengue vector distribution but also to provide objective information for taking appropriate action by the community against dengue vectors.

Effects of preservatives and killing methods on morphological features of a forensic fly, Chrysomya megacephala (Fabricius, 1794) larva

Preservation of larvae retrieved from cadavers is important in ensuring the quality and integrity of entomological specimens used for the estimation of post-mortem interval (PMI). The process of killing and preserving larvae could distort the larvae leading to inaccurate estimation of PMI. In this study, the effects of killing Chrysomya megacephala larvae with hot water at different temperatures and subsequent maintenance in various preservatives were determined. Larvae not killed by hot water but preserved directly were used as control. The types of preservative used were 10% formalin, 70% ethanol and Kahle's solution. The morphological features examined were length, turgidity, curvature and coloration of larvae. Larvae killed in 80ºC hot water have shorter mean length (12.47 ± 2.86 mm) compared to those in 60ºC hot water (12.95 ± 2.69 mm). Increasing the duration of preservation in all types of preservative caused elongations of larvae treated or untreated with hot water. There were no significant changes in larval turgidity preserved in Kahle's solution compared to other two preservatives and were unaffected by the duration of storage. Larvae preserved in Kahle's solution experienced the least changes in coloration and shape compared to other preserved larvae in 70% ethanol or 10% formalin. Larvae directly immersed alive in 70% ethanol experienced the most changes in curvature, coloration and turgidity. This study suggested that killing larvae with hot water at 80ºC and preservation in Kahle's solution is the optimum method resulting in least changes in morphological features of Ch. megacephala larvae.

Prognostic factors associated with clear cell sarcoma in 14 Chinese patients

PURPOSE. To identify prognostic factors associated with clear cell sarcomas in 14 Chinese patients. METHODS. Medical records of 7 men and 7 women (mean age, 36 years) with histologically confirmed clear cell sarcoma of tendons and aponeuroses were reviewed. Patient demographics, tumour characteristics, and treatment modalities were retrieved. Prognostic factors associated with favourable 5-year survival were determined. RESULTS. The most affected sites were the thigh (n=5) and the foot (n=4); the mean time from symptom onset to diagnosis was 9.5 months. The tumour stage at diagnosis was IIA in 8 patients, IIB in 2, and III in 4. The mean tumour size was 4.5 cm in diameter. One patient was lost to follow-up. For the remaining 13 patients, the mean time to disease-related mortality was 2.5 years. Nine patients had distant metastases; the most common sites were lungs and pleura (n=7), followed by distant lymph nodes (n=4), bone (n=2), pericardium (n=2), and brain (n=1). All patients underwent surgical excision. Three women and one man (mean age, 27 years) attained 5-year disease-free survival. All had stage IIA tumours at diagnosis. Their mean tumour size was 1.75 cm in diameter, which was significantly smaller than that of all patients (4.5 cm). Tumour size of ≤ 2.5 cm in diameter (p=0.004) and stage IIA tumour at diagnosis (p=0.04) were significant prognostic factors for 5-year survival. CONCLUSION. Tumour size of ≤ 2.5 cm and early stage tumour are associated with 5-year disease-free survival. Early detection is crucial for the prognosis of clear cell sarcomas.

Self-assembly of MinE on the membrane underlies formation of the MinE ring to sustain function of the Escherichia coli Min system

The pole-to-pole oscillation of the Min proteins in Escherichia coli results in the inhibition of aberrant polar division, thus facilitating placement of the division septum at the midcell. MinE of the Min system forms a ring-like structure that plays a critical role in triggering the oscillation cycle. However, the mechanism underlying the formation of the MinE ring remains unclear. This study demonstrates that MinE self-assembles into fibrillar structures on the supported lipid bilayer. The MinD-interacting domain of MinE shows amyloidogenic properties, providing a possible mechanism for self-assembly of MinE. Supporting the idea, mutations in residues Ile-24 and Ile-25 of the MinD-interacting domain affect fibril formation, membrane binding ability of MinE and MinD, and subcellular localization of three Min proteins. Additional mutations in residues Ile-72 and Ile-74 suggest a role of the C-terminal domain of MinE in regulating the folding propensity of the MinD-interacting domain for different molecular interactions. The study suggests a self-assembly mechanism that may underlie the ring-like structure formed by MinE-GFP observed in vivo.

A preliminary report on ants (Hymenoptera: Formicidae) recovered from forensic entomological studies conducted in different ecological habitats in Malaysia

This study reported the ant species that were recovered from monkey carcasses in three different ecological habitats in Malaysia. The study was conducted from 9 May - 10 October 2007, 6 May - 6 August 2008 and 26 May - 14 July 2009 in forested area (Gombak, Selangor), coastal area (Tanjong Sepat, Selangor) and highland area (Bukit Cincin, Pahang), respectively. Monkey carcass was used as a model for human decomposition in this study. A total of 4 replicates were used in each of the study sites. Ants were observed to prey on eggs, larvae, pupae and newly emerged flies. This study found that ant species could be found at all stages of decomposition, indicating that ants were not a significant indicator for faunal succession. However, different species of ants were obtained from monkey carcasses placed in different ecological habitats. Cardiocondyla sp. was only found on carcasses placed in the coastal area; while Pheidole longipes, Hypoponera sp. and Pachycondyla sp. were solely found on carcasses placed in the highland area. On the other hand, Pheidologeton diversus and Paratrechina longicornis were found in several ecological habitats. These data suggests that specific ant species can act as geographic indicators for different ecological habitats in forensic entomology cases in Malaysia.