Analytical and field evaluation of the Biocentric Generic HCV assay on open polyvalent PCR platforms in France and Cambodia.

BACKGROUND: Implementation of affordable methods for HCV viremia is a key priority for identifying individuals who need treatment among persons screened positive for HCV antibodies. Different HCV PCR assays for use on open polyvalent PCR platforms are currently commercially available but studies evaluating the performances of these nucleic acid tests are needed. OBJECTIVES: In the present study, we evaluated the analytical and clinical performances of a recently developed HCV RNA PCR assay for detection and quantification of HCV viremia. STUDY DESIGN: In this study the Biocentric Generic HCV PCR was compared to the Roche Cobas AmpliPrep/Cobas TaqMan HCV RNA assay. Analytical and clinical performances was evaluated on reference materials and HCV plasma samples collected in 141 patients attending at the Montpellier University Hospital in France. Field evaluation was performed on samples collected in 185 patients attending at Medical Laboratory, Institut Pasteur in Cambodia. RESULTS: The lower limit of detection ranged from 50 HCV RNA IU/ml to 300 HCV RNA IU/ml using four different Diasorin and Qiagen automated or manual extraction methods. The specificity (CI) and sensitivity of the assay were 100% (92.5-100), and 98.7% (92.3-99.9), respectively, in France, and 100% (95.5-100), and 100% (94.4-100%), respectively, in Cambodia. Bland-Altman analysis shown good agreement between the two assays including for genotypes 6 HCV, which represent the majority of HCV isolates in Cambodia. CONCLUSIONS: The Biocentric Generic HCV assay has shown overall satisfactory analytical performances and a close agreement to the Cobas HCV assay on clinical specimens collected in France and Cambodia. There is an urgent need to further evaluate commercial assays dedicated to HCV detection and quantification using open polyvalent PCR platforms in different settings.

Blister-based-laser-induced-forward-transfer: a non-contact, dry laser-based transfer method for nanomaterials.

We show that blister-based-laser-induced forward-transfer can be used to cleanly desorb and transfer nano- and micro-scale particles between substrates without exposing the particles to the laser radiation or to any chemical treatment that could damage the intrinsic electronic and optical properties of the materials. The technique uses laser pulses to induce the rapid formation of a blister on a thin metal layer deposited on glass via ablation at the metal/glass interface. Femtosecond laser pulses are advantageous for forming beams of molecules or small nanoparticles with well-defined velocity and narrow angular distributions. Both fs and ns laser pulses can be used to cleanly transfer larger nanoparticles including relatively fragile monolayer 2D transition metal dichalcogenide crystals and for direct transfer of nanoparticles from chemical vapour deposition growth substrates, although the mechanisms for inducing blister formation are different.

Defining sepsis on the wards: results of a multi-centre point-prevalence study comparing two sepsis definitions.

Our aim was to prospectively determine the predictive capabilities of SEPSIS-1 and SEPSIS-3 definitions in the emergency departments and general wards. Patients with National Early Warning Score (NEWS) of 3 or above and suspected or proven infection were enrolled over a 24-h period in 13 Welsh hospitals. The primary outcome measure was mortality within 30 days. Out of the 5422 patients screened, 431 fulfilled inclusion criteria and 380 (88%) were recruited. Using the SEPSIS-1 definition, 212 patients had sepsis. When using the SEPSIS-3 definitions with Sequential Organ Failure Assessment (SOFA) score ≥ 2, there were 272 septic patients, whereas with quickSOFA score ≥ 2, 50 patients were identified. For the prediction of primary outcome, SEPSIS-1 criteria had a sensitivity (95%CI) of 65% (54-75%) and specificity of 47% (41-53%); SEPSIS-3 criteria had a sensitivity of 86% (76-92%) and specificity of 32% (27-38%). SEPSIS-3 and SEPSIS-1 definitions were associated with a hazard ratio (95%CI) 2.7 (1.5-5.6) and 1.6 (1.3-2.5), respectively. Scoring system discrimination evaluated by receiver operating characteristic curves was highest for Sequential Organ Failure Assessment score (0.69 (95%CI 0.63-0.76)), followed by NEWS (0.58 (0.51-0.66)) (p < 0.001). Systemic inflammatory response syndrome criteria (0.55 (0.49-0.61)) and quickSOFA score (0.56 (0.49-0.64)) could not predict outcome. The SEPSIS-3 definition identified patients with the highest risk. Sequential Organ Failure Assessment score and NEWS were better predictors of poor outcome. The Sequential Organ Failure Assessment score appeared to be the best tool for identifying patients with high risk of death and sepsis-induced organ dysfunction.

Crowned spiropyran fluoroionophores with a carboxyl moiety for the selective detection of lithium ions.

The absorbance and fluorescence spectra of carboxylated spiropyrans containing methyl-1-aza-12-crown-4, methyl-1-aza-15-crown-5, methyl-1-aza-18-crown-6 moieties are compared. Characteristic changes in spectra after addition of the alkali metal salts of Li(+), Na(+), K(+) and Cs(+) were observed. Chromism induced by the binding of the metal cations was observed as an increase in absorbance and fluorescence. Of these metal cations, the Li(+) ion produced the largest change in all three spiropyran systems. Reversible photoswitching of the spiropyran-metal complexes was observed on irradiation with alternating 352 nm UV and white light. This results in reversible fluorescence based sensing of lithium ions with potential for use in a biological sensor device.

The influence of the bowel and bladder preparation protocol for radiotherapy of prostate cancer using kilo-voltage cone beam CT: Our experience.

The purpose of this study is to determine the influence of bladder and bowel preparation protocols on the dose-volume histograms (DVHs) of these organs using the cone beam computed tomography (CBCT)-based intensity modulated radiotherapy (IMRT) treatment planning for prostate cancer patients. The pelvic DVHs of 12 prostate cancer patients were studied using CBCT images obtained immediately before each treatment. Six patients had bladder and bowel preparation protocol whilst the other six patients were the control group. Contoured bladder and rectal volumes on CBCT images were compared with planning computed tomography. All patients were treated with IMRT with 7800 cGy in 39 fractions over 8 weeks. Compared with the patient with bladder preparation protocol, patients without bladder preparation instruction had higher bladder volume and dose variation. The maximum variation in bladder volume was as high as 98% in the control group. Without bowel preparation protocol, the rectal volumes were more variability. Owing to changes in rectal filling on the day of treatment, the maximum variation in rectal volume was as high as + 96%. With bowel preparation protocol, the maximum rectum volume variations were less than 25%. The changes in prostate target dose compared with planning dose were minimal as would be expected from positioning with daily image guidance and gold seed implanted.

Formation of Organic Molecular Nanocrystals under Rigid Confinement with Analysis by Solid State NMR.

Crystallization in rigid confinement is a promising method to obtain organic molecular nanocrystals. However, the crystallization behavior and the related characterization methods are not well studied. Here we present a systematic study of the nucleation of organic molecular nanocrystals in rigid pores. Four different compounds were studied, ibuprofen, fenofibrate, griseofulvin, and indomethacin, which range from simple to complex molecules. Solid-state Nuclear Magnetic Resonance (NMR) was employed to analyse the structure of these compounds inside pores which are difficult to characterize by other analytical methods. We successfully demonstrated the production of nano-crystalline ibuprofen, fenofibrate and griseofulvin in porous silica particles with ~ 40 nm pores. These nanocrystals showed significant enhancement in dissolution rates. These results help advance the fundamental understanding of nucleation under rigid confinement and may lead to potential applications in developing new formulations in the pharmaceutical industry.

Evaluation of the utility of hospital databases to provide data in assessing the quality of strabismus surgery.

AIMS AND BACKGROUND: Rates of re-operation, which may be related to an unsatisfactory surgical outcome, can provide a long-term index of the quality of strabismus surgery. This study aims to evaluate the utility of the Scottish Morbidity Records (SMR1) in determining nature and rates of re-operation for strabismus at the Royal Hospital for Sick Children (RHSC), Glasgow. METHODS: SMR1 data on strabismus surgery performed on children aged between 0 and 17 years at the RHSC, Glasgow, between January 2000 and March 2009 were analysed. RESULTS: In total, 1376 strabismus procedures were carried out on 1274 individuals. The median time between first and subsequent procedures was 19 months; the commonest reasons being under-correction or recurrence. The Kaplan-Meier rate of undergoing re-operation was 7.4% after 9 years with a 95% confidence interval of 5.4-9.9%. CONCLUSIONS: The SMR1 is a useful source of hospital-based and population data. With supplementation from parallel databases, routine administrative databases like the SMR1 can provide better quality data to inform practice.

Decrease in the rate of esotropia surgery in the United Kingdom from 2000 to 2010.

BACKGROUND/AIMS: A decrease in strabismus surgery in children has been previously documented in the UK. This study aims to examine whether the incidence of strabismus surgery in children is still decreasing and, if so, the possible reasons for this. METHODS: Data on strabismus surgery from 2000 to 2010 in children in Scotland, England and Wales were obtained. Population statistics for the age group 0-14 years were obtained for England, Scotland and Wales. Annual incidence of strabismus surgery per 100 000 age-specific population was calculated. Data on the number of sight tests in children conducted by the hospital eye service from 1995 to 2004 in these regions were also obtained. RESULTS: From 2000 to 2006, the annual incidence of paediatric strabismus operations decreased significantly in England (p=0.01) and Scotland (p=0.03), and showed a decreasing trend in Wales (p=0.06). Surgical rates, however, remained fairly constant from 2006 to 2010. The number of sight tests in children performed by the hospital eye service has remained fairly constant from 1995 to 2004 in England, Wales and Scotland. CONCLUSIONS: Rates of strabismus surgery in children, especially for esotropia, continued to decrease between 2000 and 2006, but may have stabilised from 2006 to 2010.

Quantification of voriconazole in human bronchoalveolar lavage fluid using high-performance liquid chromatography with fluorescence detection.

The quantification of voriconazole concentration in lung epithelial lining fluid to facilitate the management of pulmonary fungal colonisation or aspergillosis is of increasing interest. An accurate and reproducible high-performance liquid chromatography method to quantify voriconazole in human bronchoalveolar lavage (BAL) fluid was developed and validated. BAL samples were concentrated by freeze-drying and reconstituted with water prior to deproteinisation. Separation was achieved with a C18 column employing fluorescence detection (excitation: 260nm, emission: 370nm). The calibration curves were linear from 2.5 to 500ng/mL. The intra- and inter-day precisions were within 7%. Accuracies ranged from 102% to 107%. The clinical applicability was established by successful measurement of voriconazole concentrations in lung transplant recipients. The assay provides an alternative approach for those with negligible access to liquid chromatography-tandem mass spectrometry instrumentation.

Androgen receptor phosphorylation at serine 515 by Cdk1 predicts biochemical relapse in prostate cancer patients.

BACKGROUND: Prostate cancer cell growth is dependent upon androgen receptor (AR) activation, which is regulated by specific kinases. The aim of the current study is to establish if AR phosphorylation by Cdk1 or ERK1/2 is of prognostic significance. METHODS: Scansite 2.0 was utilised to predict which AR sites are phosphorylated by Cdk1 and ERK1/2. Immunohistochemistry for these sites was then performed on 90 hormone-naive prostate cancer specimens. The interaction between Cdk1/ERK1/2 and AR phosphorylation was investigated in vitro using LNCaP cells. RESULTS: Phosphorylation of AR at serine 515 (pAR(S515)) and PSA at diagnosis were independently associated with decreased time to biochemical relapse. Cdk1 and pCdk1(161), but not ERK1/2, correlated with pAR(S515). High expression of pAR(S515) in patients with a PSA at diagnosis of ≤20 ng ml(-1) was associated with shorter time to biochemical relapse (P=0.019). This translated into a reduction in disease-specific survival (10-year survival, 38.1% vs 100%, P<0.001). In vitro studies demonstrated that treatment with Roscovitine (a Cdk inhibitor) caused a reduction in pCdk1(161) expression, pAR(S515)expression and cellular proliferation. CONCLUSION: In prostate cancer patients with PSA at diagnosis of ≤20 ng ml(-1), phosphorylation of AR at serine 515 by Cdk1 may be an independent prognostic marker.

Fluoroquinolone and pyrazinamide resistance in multidrug-resistant tuberculosis.

In a study performed in Cambodia, a higher number of tuberculosis (TB) strains with mutations in the pncA gene associated with pyrazinamide resistance (PZA-R) was found in fluoroquinolone-resistant (FQ-R) multidrug-resistant (MDR) strains (93%), compared with 47% in MDR and 3% in non-MDR strains. This emphasises the need for easy and rapid tests for identification of PZA-R for efficient treatment of MDR-TB.

A description of influenza-like illness (ILI) sentinel surveillance in Cambodia, 2006-2008.

Influenza-Like Illness (ILI) sentinel surveillance was initiated by the Communicable Disease Control Department (CDC), Ministry of Health, Cambodia and its partners to evaluate the epidemiology of influenza and identify the circulating strains. The surveillance started in late 2006 in four sentinel sites. The objectives of this study were 1) to document the incidence of LI and confirmed influenza cases reported in the national surveillance system from 2006 to 2008, just after the system and the definition were revised, 2) to identify the strains of influenza virus, 3) to compare the major demographic and clinical characteristics between ILI patients having positive and negative tests for influenza virus. An ILI case was defined as having a fever of at least 38 degrees C (axillary), cough or sore throat. A total of 155,866 ILI cases were reported to the CDC from 4 sentinel sites in Cambodia from August 2006 to December 2008. Specimens were collected in 1.8%. Of these, 9.6% tested positive for influenza. Influenza was observed to occur mainly from August to December, with a clear seasonal peak in October, as shown in the data from 2008. A new case definition beginning in August 2008 resulted in a decrease in weekly RI reported cases (from an average of 1,474 cases to 54 cases) and the proportion of positive tests for influenza increased (5.3% vs 29.3%). Influenza and ILI are seasonal in Cambodia. A higher body temperature was used to define ILI, which improved the influenza positivity rates.

The credibility of the Breast Cancer Risk Assessment (BCRA) tool for Asians.

This paper presents an overview of the Breast Cancer Risk Assessment (BCRA) Tool, assessing the credibility of the BCRA tool in estimating the risk of developing breast cancer for Asians and the carrying out of tests to identify the changes in the risks that follow with changes in one or more risk factors of the tool. It is essential to increase the awareness of women of their risk of developing breast cancer, as it is not surprising that some women may not even be conscious of the individual factors that might contribute to the increase of their risk of developing breast cancer. On the other hand, relatively accurate means of determining increases in relative risks of developing breast cancer due to changes in some of the risk factors are also important. This is done so that unnecessary worry due to an overestimation of an individual's risk of developing breast cancer can be avoided. Due to the origin of the BCRA tool which is used in this study, it is important to verify the validity of the tool on Asians and to identify, as far as possible, the effect that each risk factor has on individuals. The effect that a specific risk factor has on a white woman may not be exactly the same for that of an Asian woman. As the above-mentioned tool has been arrived at using the statistics and databases of white women, in this work, tests have been carried out to determine the suitability of the tool on Asian women. On top of that, various tests are also carried out to determine the effects of the change of certain risk factors on a woman's risk of developing breast cancer. These factors include age, number of breast biopsies and number of first-degree relatives with breast cancer. Five-year risks and lifetime risks are also looked into separately with the change of each of these factors.

Etiology of acute lower respiratory tract infection in children at Srinagarind Hospital, Khon Kaen, Thailand.

We investigated the etiology of acute lower respiratory infection (ALRI) in children under 5 admitted to Srinagarind Hospital. The causative bacteria and viruses were determined by hemoculture and viral isolation from blood and nasopharyngeal aspirate samples. Antigens of respiratory syncytial virus (RSV) and Chlamydia trachomatis were detected using EIA. The 74 children less than 5 years of age with ALRI enrolled in our study were diagnosed with pneumonia (75.7%), croup (16.2%), and bronchiolitis (8.1%), respectively. Examination of blood or nasopharyngeal aspirate revealed viral or bacterial infections in 26 and 22 cases, respectively, whereas 5 of the children aged under 1 year (10%) were diagnosed with pneumonia caused by Chlamydia trachomatis. RSV was the most common virus detected (24.3%) and was associated with pneumonia and bronchiolitis, while the parainfluenza virus was the primary cause of croup. In cases of pneumonia, bacterial infections were identified in almost all of the cases: and Streptococcus pneumoniae and Haemophilus influenzae were the most commonly isolated (at 8.9% each). Mixed infections were detected in 8 cases (10.8%). The incidence of RSV infection peaked during the especially warm and cool seasons, whereas the bacterial infections were primarily associated with the relatively cool season. Our study indicates that a combined pneumococcal and Hib vaccine and a RSV vaccine would reduce the high rate of pneumonia in children under 5 years of age in Northeast Thailand.

Behavioural and serological human immunodeficiency virus risk factors among female commercial sex workers in Cambodia.

BACKGROUND: The spread of human immunodeficiency virus (HIV) in Cambodia is mainly caused by sexual transmission and the high-risk group in this country are female commercial sex workers (CSW). There are two types of CSW, direct CSW (DCSW) and indirect CSW (IDCSW), who are different from each other in sexual activities. This study was conducted in order to describe the risk factors on HIV for each type of CSW, and to establish effective preventive strategies against the HIV epidemic among CSW. METHODS: The participants, 143 DCSW and 94 IDCSW, were interviewed using a questionnaire to determine their demographic characteristics and behaviour. Blood samples were taken for serological tests on HIV, Chlamydia trachomatis and syphilis. The association between their behavioural pattern and their serological results was analysed. RESULTS: The questionnaire study showed that IDCSW had a riskier behavioural pattern than DCSW. The HIV seroprevalence rates of the DCSW and the IDCSW were 52.4% and 22.3%, respectively. Univariate logistic analyses showed a significant association between HIV antibody (HIV-Ab) and current age, age at commencement of commercial sex work, duration of commercial sex work, and the seropositivity of Chlamydia trachomatis-IgG antibody (CT-IgG-Ab) among the DCSW. The analyses also showed a significant relationship between HIV-Ab and CT-IgG-Ab among the IDCSW. CONCLUSIONS: Improving condom use rate is very important in order to prevent an HIV epidemic among the two types of CSW. This study also suggests it is important to prevent sexually transmitted disease (STD) such as Chlamydia trachomatis infection. The STD control programme could be efficient for HIV prevention, especially among DCSW.

Cross-sectional study on risk factors of HIV among female commercial sex workers in Cambodia.

To describe epidemiological features on HIV prevalence among female commercial sex workers (CSWs), a cross-sectional study on sexual behaviour and serological prevalence was carried out in Cambodia. The CSWs were interviewed on their demographic characters and behaviour and their blood samples were taken for testing on sexually transmitted diseases, including HIV, Chlamydia trachomatis, syphilis, and hepatitis B. Associations between risk factors and HIV seropositivity were analysed. High seroprevalence of HIV and Chlamydia trachomatis IgG antibody (CT-IgG-Ab) was shown among the CSWs (54 and 81.7%, respectively). Univariate logistic regression analyses showed an association between HIV seropositivity and age, duration of prostitution, the number of clients per day and CT-IgG-Ab. Especially, high-titre chlamydial seropositivity showed a strong significant association with HIV prevalence. In multiple logistic regression analyses, CT-IgG-Ab with higher titre was significantly independently related to HIV infection. These suggest that existence of Chlamydia trachomatis is highly related to HIV prevalence.

Survey of the prevalence of asthma, allergic rhinitis and eczema in schoolchildren from Khon Kaen, Northeast Thailand. an ISAAC study. International Study of Asthma and Allergies in Childhood.

This survey of schoolchildren from Khon Kaen, Northeast Thailand used the standardized ISAAC questionnaires to estimate the prevalence of asthma and other allergic diseases and to compare the results with two previous studies. A total of 6,068 questionnaires were analyzed (2,658, 45.6% males from the 6 to 7 years old group and 3,410, 49.5% male from the 13 to 14 years old group). The three predominant cumulative and 12-month conditions discerned from the written questionnaires among the 6 to 7 vs 13 to 14 years old were: wheezing, at 18.6% and 10.2% vs 20.5% and 11.0%; rhinitis at 38.4% and 33.5% vs 59.4% and 42.5%; and eczema at 18.0% and 15.2% vs 9.9% and 7.4%, respectively. The observed prevalences in our study were similar to those found in Bangkok and slightly higher than those in Chiang Mai, except for 'exercise wheezing' in older children which was two times higher in our study than in the two previous studies. Our study showed seasonal variation of the 'nose' symptoms. The peak prevalence was in the relatively cool and dry season (between November and January), which was the same pattern as Chiang Mai but different from Bangkok (which had a perennial pattern and less climatic variation). Our results concurred with the two previous Thai ISAAC studies. There is a high prevalence of asthma and other allergic diseases among Thai children and there has been a four-fold increase in symptoms since the last decade. If the trend persists asthma and allergic disease may become a pressing health concern of the country.

An axisymmetric contact model of ultra high molecular weight polyethylene cups against metallic femoral heads for artificial hip joint replacements.

Contact mechanics of ultra high molecular weight polyethylene (UHMWPE) cups against metallic femoral heads for artificial hip joints is considered in this study. Both the experimental measurement of the contact area and the finite element prediction of the contact radius, maximum contact pressure and maximum Von Mises stress have been carried out for a wide range of contemporary artificial hip joints. Good agreement of the contact radius has been found between the experimental measurements and the finite element predictions based upon an elastic modulus of 1000 MPa and a Poisson's ratio of 0.4 for UHMWPE material under various loads up to 2.5 kN. It has been shown that the half contact angle for all the cup/head combinations considered in this study is between 40 degrees and 50 degrees under a load of 2.5 kN. The importance of this result has been discussed with respect to the anatomical position of the cup when placed in the body and the selection of a simple wear-screening test for artificial hip joints. The predicted contact radius and maximum contact pressure from the finite element model have also been compared with a simple elasticity analysis. It has been shown that the difference in the predicted contact radius between the two methods is reduced for more conforming contacts between the femoral head and the acetabular cup and smaller UHMWPE cup thickness. However, good agreement of the predicted maximum contact pressure has been found for all the combinations of the femoral head and the acetabular cup considered in this study. The importance of contact mechanics on the clinical performance of artificial hip joint replacements has also been discussed.

Co-infection and synergy of human immunodeficiency virus-1 and herpes simplex virus-1.

The human immunodeficiency virus (HIV-1) uses the CD4 molecule, expressed by T helper cells and activated macrophages, as a receptor for entry into host cells. In tissues co-infected with herpes simplex type 1 (HSV-1), HIV-1 virions were observed to infect keratinocytes, which, because they lack the CD4 molecule, are normally incapable of being infected by HIV-1. Although a number of other viruses have been reported to enhance HIV-1 viral transcription in vitro, this is the first in-vivo report to our knowledge of reciprocal enhancement of viral replication associated with co-infection of keratinocytes and macrophages by HIV-1 and HSV-1 in patients with AIDS and non-genital herpes simplex lesions. The virions in the co-infected cells were larger, morphologically atypical, and appear to be hybrids; most contain the HIV-1 envelope necessary for infectivity. The increased viral load and the proximity of the virions to the cutaneous surface may lead to increased risk of transcutaneous transmission of both viruses. These findings point to the need for incorporation of suppressive treatment for herpes simplex in the treatment of AIDS.