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.

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.

Motor and somatosensory abnormalities are significant etiological factors for adolescent idiopathic scoliosis.

OBJECTIVE: In adolescent idiopathic scoliosis (AIS), we explore the role of lateralized motor and somatosensory abnormalities as a possible etiological factor. METHODS: Intraoperative transcranial electrical stimulation was performed in 15 AIS and 14 adult degenerative scoliosis (ADS) patients. Inter-side motor output balance (MOB) by comparing the ratios of right to left motor evoked potentials (MEP) amplitudes, and inter-side motor output excitability (MOE) computed with MEP amplitude, was determined separately for both patients groups. For somatosensory evoked potentials (SSEP), peak to peak P37 amplitudes from right and left lower limb SSEP and inter-side P37 amplitude ratios were obtained. RESULTS: Inter-side MOB was significantly asymmetric in AIS patients, contributed mainly by inter-side MOB changes in the upper than the lower limbs. Inter-side MOE comparisons of ipsilateral and contralateral MEP amplitudes were significantly different between AIS and ADS patients. Mean upper limb MEP amplitudes were significantly reduced in AIS patients. Amplitude of the right upper limb MEPs were positively correlated with inter-side MEP ratio. AIS patients show larger mean MEP amplitudes on the same side as the scoliotic curve. Overall, no correlation of Cobb's angle or total levels of scoliosis involvement with inter-side MOB and MOE parameters was found. Inter-side SSEP ratios were significantly higher in AIS patients. CONCLUSIONS: Primary dysfunctional and distributed motor output contributing to abnormalities of inter-side MOB and MOE changes involving the upper limbs is evident in AIS. Simultaneous but independent somatosensory and motor observations seen these patients suggest a central mechanism as an etiological factor.

In vitro antibacterial activity and physicochemical properties of a crude methanol extract of the larvae of the blow fly Lucilia cuprina.

The emergence of multidrug-resistant bacterial strains has prompted the reintroduction of maggot therapy in the treatment of chronic, infected wounds. Many previous studies have demonstrated the potent antibacterial activity of larval excretions/secretions of the blowfly Lucilia sericata (Meigen) (Diptera:Calliphoridae) against bacteria. However, the antibacterial activity of its sibling species, Lucilia cuprina (Wiedemann) (Diptera:Calliphoridae) against a wide range of pathogenic bacteria has never been determined. The aim of this study was to develop a new procedure to produce whole body extract of larvae of L. cuprina via methanol extraction as well as to demonstrate the in vitro antibacterial activity of this extract against seven selected wound pathogens (Staphylococcus aureus, methicillin-resistant S. aureus, S. epidermidis, Streptococcus pyogenes, Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli). The turbidimetric assay demonstrated that L. cuprina larval extract was significantly potent against all bacteria tested (P < 0.001). Additionally, colony-forming unit (CFU), agar well diffusion and minimum inhibitory concentration assays have confirmed the apparent potency of larval extract against P. aeruginosa. The reconstituted larval extract was highly robust and thermally stable. These observations substantiated the feasibility of the methanol extraction method in the production of larval extract.

Secondary prevention of osteoporotic fractures--an "OPTIMAL" model of care from Singapore.

UNLABELLED: A significant care gap exists in the management of osteoporotic fractures. Osteoporosis Patient Targeted and Integrated Management for Active Living (OPTIMAL) is a secondary fracture prevention program instituted in the public hospitals of Singapore. We aim to describe the operational characteristics of OPTIMAL and initial audit data of patients who were recruited into the program at Singapore General Hospital. INTRODUCTION: Fractures often represent the first opportunity for care of osteoporosis. However, a significant care gap still exists in the management of these sentinel events and underdiagnosis and undertreatment of osteoporotic fractures are prevalent worldwide. Fracture liaison services run by care coordinators have been shown to reduce the fracture care gap. OPTIMAL is a clinician champion-driven, case manager-run secondary fracture prevention program set up in the public hospitals of Singapore in 2008. METHODS: We present the operational characteristics and initial audit data of OPTIMAL from the largest tertiary teaching hospital in Singapore. RESULTS: One thousand and fourteen patients have been recruited into OPTIMAL at our hospital since 2008, and 476 patients are currently in active follow-up. Two hundred and eighty-seven patients had completed a 2-year follow-up at the hospital as of August 2012 and were evaluated; 97.5% of these patients had DXA evaluation upon enrollment into the program, and 62% of the patients reported compliance with an exercise program over the 2-year follow-up. Compliance to osteoporosis medications as estimated by the medication possession ratio (MPR) was 72.8 ± 34.5% at 2 years with patients maintaining good compliance (MPR ≥ 80%) for an average of 20.2 months (95% CI 19.3-21.1). CONCLUSION: Our report provides the first compelling evidence of the potential success of a secondary fracture prevention program from an Asian country. The ultimate success of the program will be determined by fracture outcomes and cost effectiveness, but in the interim, clear evidence of enhanced assessment and treatment rates has been demonstrated.

Adjuvant hepatic intra-arterial iodine-131-lipiodol following curative resection of hepatocellular carcinoma: a prospective randomized trial.

BACKGROUND: The purpose of the present study was to determine whether intrahepatic injection of (131)I-lipiodol (Lipiodol) is effective against recurrence of surgically resected hepatocellular carcinoma (HCC). METHODS: From June 2001 through March 2007, this nationwide multi-center prospective randomized controlled trial enrolled 103 patients 4-6 weeks after curative resection of HCC with complete recovery (52: Lipiodol, 51: Control). Follow-up was every 3 months for 1 year, then every 6 months. Primary and secondary endpoints were recurrence-free survival (RFS) and overall survival (OS), respectively, both of which were evaluated by the Kaplan-Meier technique and summarized by the hazard ratio (HR). The design was based on information obtained from a similar trial that had been conducted in Hong Kong. RESULTS: The Lipiodol group showed a small, and nonsignificant, improvement over control in RFS (HR = 0.75; 95 % confidence interval [95 % CI] 0.46-1.23; p = 0.25) and OS (HR = 0.88; 95 % CI 0.51-1.51; p = 0.64). Only two serious adverse events were reported, both with hypothyroidism caused by (131)I-lipiodol and hepatic artery dissection during angiography. CONCLUSIONS: The randomized trial provides insufficient evidence to recommend the routine use of (131)I-lipiodol in these patients.

Systematic review of outcomes of liver resection for early hepatocellular carcinoma within the Milan criteria.

BACKGROUND: Long-term overall survival after liver resection in patients with hepatocellular carcinoma (HCC) within the Milan criteria has been reported to improve in recent years. This study systematically reviewed the outcomes of surgical resection for HCC in patients with good liver function and meeting the Milan criteria for early HCC, published in the past 10 years. METHODS: A literature search was conducted in PubMed for papers on outcomes of surgical resection for HCC published between January 2000 and December 2010. Cochrane systematic review methodology was used for this review. The primary outcome was overall survival. Secondary outcomes included operative mortality and disease-free survival. Studies that focused on geriatric populations, paediatric populations, a subset of the Milan criteria (such solitary tumours) or included patients with incidental tumours were excluded, as were case reports, conference abstracts, and studies with a large proportion of Child-Pugh grade C liver cirrhosis or unknown Child-Pugh status. RESULTS: Of 152 studies reviewed, two randomized clinical trials and 27 retrospective case series were eligible for inclusion. The 5-year overall survival rate after resection of HCC ranged from 27 to 81 (median 67) per cent, and the median disease-free survival rate from 21 to 57 (median 37) per cent. There was a trend towards improved overall survival in recent years. The operative mortality rate ranged from 0 to 5 (median 0·7) per cent. CONCLUSION: Surgical resection offers good overall survival for patients with HCC within the Milan criteria and with good liver function, although recurrence rates remain high. Outcomes have tended to improve in more recent years.

A virtual-reality subtotal tonsillectomy simulator.

OBJECTIVES: To develop a virtual-reality subtotal tonsillectomy simulation for surgical training. MATERIALS AND METHODS: Computer models of a male patient's head and throat, and the surgical instrument, were created. These models were combined with custom-built simulation software. Recently developed tissue simulation technology that exploits recent developments in programmable graphics processing units was used to model tonsillar tissue in a way that allows surgical interaction whilst providing accurate tactile feedback. Current real-time rendering techniques were used to provide realistic visuals. Iterative refinements were made to the simulation, and in particular the tissue simulation, in consultation with relevantly experienced surgeons. RESULTS: We have used newly developed tissue simulation technology to developed a novel virtual-reality subtotal tonsillectomy simulation for surgical training, the first of its kind. CONCLUSION: Early feedback suggests that this simulator can help surgeons to rapidly acquire subtotal tonsillectomy surgical skills in a risk-free and realistic virtual environment.

Meteorological factors and El Niño Southern Oscillation are independently associated with dengue infections.

Our objective was to determine the association between temperature, humidity, rainfall and dengue activity in Singapore, after taking into account lag periods as well as long-term climate variability such as the El Niño Southern Oscillation Index (SOI). We used a Poisson model which allowed for autocorrelation and overdispersion in the data. We found weekly mean temperature and mean relative humidity as well as SOI to be significantly and independently associated with dengue notifications. There was an interaction effect by periods of dengue outbreaks, but periods where El Niño was present did not moderate the relationship between humidity and temperature with dengue notifications. Our results help to understand the temporal trends of dengue in Singapore, and further reinforce the findings that meteorological factors are important in the epidemiology of dengue.

Randomised double-blind trial of megestrol acetate vs placebo in treatment-naive advanced hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is the third leading cause of cancer deaths worldwide. We tested megestrol acetate (MA) against placebo in the treatment of advanced HCC. METHODS: From 2002 through 2007, this randomised double-blind trial enrolled 204 patients with treatment-naive advanced HCC (Eastern Cooperative Oncology Group (ECOG) performance rating of 0-3) from specialist care centres in six Asia-Pacific nations. Patients received placebo or MA (320 mg day(-1)). End points were overall survival (OS) and quality of life. RESULTS: An adverse but not statistically significant difference in OS was found for MA vs placebo: median values 1.88 and 2.14 months, respectively (hazard ratio (HR)=1.25, 95% CI=0.92-1.71, P=0.16). However, OS was similar among patients of good functional status (Child-Pugh A and ECOG 0, 1 or 2) (44.3%) in both treatment groups, with the adverse effect of MA confined to those of poor status. Megestrol acetate patients had a worse global health status (not statistically significant) but reduced levels of appetite loss and nausea/vomiting. CONCLUSION: Megestrol acetate has no role in prolonging OS in advanced treatment-naive HCC. Overall survival with placebo differed markedly from that in similar trials conducted elsewhere, suggesting therapeutic outcomes may be strongly dependent on ECOG status and Child-Pugh score.

Lack of association of dengue activity with haze.

Dengue activity depends on fluctuations in Aedes populations which in turn are known to be influenced by climate factors including temperature, humidity and rainfall. It has been hypothesized that haze may reduce dengue transmission. Due to its geographical location Singapore suffers almost every year from hazes caused by wildfires from Indonesia. Such hazes have a significant impact on pollution indexes in Singapore. We set out to study the relationship of dengue activity and haze (measured as pollution standard index) in Singapore, using ARIMA models. We ran different univariate models, each encompassing a different lag period for the effects of haze and temperature (from lag 0 to lag 12 weeks). We analysed the data on a natural logarithmic scale to stabilize the variance and improve the estimation. No association between dengue activity and haze was found. Our findings do not lend support to the hypothesis that haze is associated with reduced dengue activity in Singapore.

A double-blind, placebo-controlled, randomized, multicenter study to investigate CHInese Medicine Neuroaid Efficacy on Stroke recovery (CHIMES Study).

UNLABELLED: Rationale Traditional Chinese Medications(TCM) have been reported to have beneficial effects in stroke patients, but were not rigorously evaluated by GCP standards. Aim This study tests the hypothesis that Neuroaid, a TCM widely used in China post-stroke, is superior to placebo in reducing neurological deficit and improving functional outcome in patients with acute cerebral infarction of an intermediate severity. Design This is a multicenter, randomised, double-blind, placebo-controlled study of Neuroaid in ischemic stroke patients with National Institute of Health Stroke Scale(NIHSS) 6-14 treated within 48 h of stroke onset. Neuroaid or placebo is taken (4 capsules) 3 times daily for 3 months. Treatments are assigned using block randomization, stratified for centers, via a central web-randomization system. With a power of 90% and two-sided test of 5% type I error, a sample size is 874. Allowing for a drop-out rate of up to 20%, 1100 individuals should be enrolled in this study. Study Outcomes The primary efficacy endpoint is the modified Rankin Scale(mRS) grades at 3 months. Secondary efficacy endpoints are the NIHSS score at 3 months; difference of NIHSS scores between baseline and 10 days, and between baseline and 3 months; difference of NIHSS sub-scores between baseline and 10 days, and between baseline and 3 months; mRS at 10 days, 1 month, and 3 months; Barthel index at 3 months; Mini Mental State Examination at 10 days and 3 months. Safety outcomes include complete blood count, renal and liver panels, and electrocardiogram. STUDY REGISTRATION: ClinicalTrials.gov identifier: NCT00554723.

The value of bilateral ipsilateral and contralateral motor evoked potential monitoring in scoliosis surgery.

Intraoperative monitoring (IOM) of the motor pathways is a routine procedure for ensuring integrity of corticospinal tracts during scoliosis surgery. We have previously demonstrated presence of ipsilateral motor evoked potentials (MEPs) during IOM for scoliosis surgery, but its significance was uncertain. In this case series, we show concurrent ipsilateral and contralateral MEP amplitude changes obtained with cortical stimulation are of value in reducing false positive observations during IOM. The use of this easily recordable MEP is thus advocated as a diagnostic adjunct to contralateral MEPs for scoliosis and spinal surgery.

Diagnostic utility of F waves in cervical radiculopathy: electrophysiological and magnetic resonance imaging correlation.

OBJECTIVE: F wave study is a simple, non-invasive method commonly utilized for evaluation of cervical root lesions. Its diagnostic sensitivity is low. There are no large series comparing F wave studies with MRI as a reference standard. PATIENTS AND METHODS: We performed F wave studies in 30 controls (15 men; mean age: 50 years; standard deviation: 17.9 years; range: 21-80 years) and, prospectively, 31 patients (19 men; mean age: 48 years; standard deviation: 16.2 years; range: 26-79 years) referred for evaluation of cervical spondylotic radiculopathy (CSR). All patients' MRIs were compared with F wave parameters. RESULTS: Combined utilization of minimal F latency, F chronodispersion, F persistence and side to side differences resulted in 55% sensitivity and 100% side concordance for detecting CSR, with MRI as a comparison standard. F wave parameters also provided complementary information to needle electromyography in the diagnostic evaluation of CSR. Although F waves were not indicative of radiculopathy levels, 4/31 (13%) of cases had at least one abnormal F wave parameter, despite normal electromyography findings. CONCLUSIONS: Combined utilization of multiple F wave parameters is a useful, diagnostic adjunct in the electrophysiological evaluation of CSR.

Cutaneous silent periods in the evaluation of cord compression in cervical spondylosis.

OBJECTIVE: The clinical diagnosis of cervical spondylotic myelopathy (CSM) may be challenging in patients with cervical spondylosis (CS). Routine nerve conduction studies (NCS) may not evaluate cord compression adequately. METHODS: We obtained cutaneous silent periods (CSP) in 26 consecutive patients presenting with clinical features of CS, in comparison with 30 normal controls. The results were also compared with transcranial magnetic stimulation (TMS) findings, and magnetic resonance imaging of the cervical cord as the gold standard. RESULTS: CSP findings showed similarly high sensitivity of up to 96% with TMS in evaluating cervical cord dysfunction. CONCLUSION: In specific clinical settings, CSP is of value for the diagnosis of CSM in CS. CSP measurement is advocated as a simple and rapid diagnostic adjunct to NCS in evaluating CS patients with possible cord compromise.

Traction and spica casting for closed femoral shaft fractures in children.

PURPOSE: To evaluate the treatment outcome of skin traction followed by spica casting for closed femoral shaft fractures in children. METHODS: Between September 1997 and December 2001 inclusive, outcomes of 63 children aged one month to 15 (mean, 5.3) years with closed femoral shaft fractures managed with skin traction and spica casting were reviewed. Depending on age, patients were kept in traction from 2 to 15 (median, 9) days, then in spica casts for 2 to 8 (median, 5) weeks. RESULTS: Bony union took 3 to 12 (median, 6) weeks. There were no malunion, nonunion, or rotational deformities. Nor were there any significant limb length discrepancies, pressure sores, or nerve palsies. On no occasion was a spica cast removed and reapplied for loss of fracture reduction. At final follow-up, limb length discrepancy was noted in 14 (22%) of the patients, but none had a discrepancy of greater than 1.5 cm or a short-legged gait. CONCLUSION: Skin traction followed by spica casting for closed femoral shaft fractures in children is safe, cost-effective and associated with a low complication rate. It is effective in children below 5 years of age and no less effective in older children, except in instances of open fracture, multiple fractures, or older children with large statures, which conditions render them intolerant to spica casts.

Congenital osteofibrous dysplasia associated with pseudoarthrosis of the tibia and fibula.

The association between congenital pseudoarthrosis and osteofibrous dysplasia of the tibia and fibula is a rare entity that has been recently recognized. We report a male newborn who was found to have swelling and deformity of the left lower leg. Radiographs and magnetic resonance imaging showed an extensive destructive lesion of the tibial shaft, with dysplastic congenital pseudoarthrosis of the lower fibula. Histopathological examination confirmed the diagnosis of congenital pseudoarthrosis of the tibia and fibula with underlying osteofibrous dysplasia involving both bones. Immunohistochemical stains showed cytokeratin positivity.

Biometrical aspects of drug development.

Once the activity of a compound has been established in the laboratory (usually by use of experimental animals) the next stage of development is to bring this forward to humans in early-phase clinical trials. A pharmacokinetic study aims to establish an effective dosing regimen for the compound in order to reach concentrations within the therapeutic window as quickly as possible. The aim of the phase I trials is typically to determine a maximal safe dose with which more rigorous investigation of activity in a phase II trial can be conducted. This chapter deals with statistical issues related to the design of phase I studies.

Intraoperative monitoring study of ipsilateral motor evoked potentials in scoliosis surgery.

Ipsilateral motor evoked potentials (MEPs) in spinal cord surgery intraoperative monitoring is not well studied. We show that ipsilateral MEPs have significantly larger amplitudes and were elicited with lower stimulation intensities than contralateral MEPs. The possible underlying mechanisms are discussed based on current knowledge of corticospinal pathways. Ipsilateral MEPs may provide additional information on the integrity of descending motor tracts during spinal surgery monitoring.

Transcranial magnetic stimulation screening for cord compression in cervical spondylosis.

OBJECTIVE: Cervical spondylosis (CS) often results in various degrees of cord compression, which can be evaluated functionally with transcranial magnetic stimulation (TMS). We investigate the use of TMS as a screening tool for myelopathy in CS. METHODS: We prospectively studied 231 patients classified into Groups 1 to 4 based on MRI grading of severity of cord compromise. TMS elicited central motor conduction times and motor evoked potential (MEP) amplitudes in all 4 limbs. The results were compared with those from 45 healthy controls. RESULTS: TMS showed 98% sensitivity and 98% specificity for cord abnormality using MRI as reference standard. CONCLUSIONS: MEP abnormalities are useful for electrophysiological evaluation of cord compression in CS. While TMS is not a substitute for MRI, it is of value as a rapid, inexpensive and non-invasive technique for screening patients before MRI studies.