A capillary electrophoretic method for the separation of the aminoglutethimide (AGT) enantiomers using methylated-beta-cyclodextrin (M-beta-CD) as chiral selector is described. Several parameters affecting the separation were studied, including the type and concentration of chiral selector, buffer pH, voltage and temperature. Good chiral separation of the racemic mixture was achieved in less than 9 min with resolution factor Rs=2.1, using a fused-silica capillary and a background electrolyte (BGE) of tris-phosphate buffer solution (50 mmol L(-1), pH 3.0) containing 30 mgm L(-1) of M-beta-CD. The separation was carried out in normal polarity mode at 25 degrees C, 16 kV and using hydrostatic injection. Acceptable validation criteria for selectivity, linearity, precision, and accuracy/recovery were included. The proposed method was successfully applied to the assay of AGT enantiomers in pharmaceutical formulations. The computational calculations for the inclusion complexes of the R- and S-AGT-M-beta-CD rationalized the reasons for the different migration times between the AGT enantiomers.
Hand-assisted laparoscopic nephrectomy (HAL-N) and nephroureterectomy (HAL-NU) were introduced to bridge the gap between open and laparoscopic surgery. This newer technique has the benefits of both laparoscopic and open surgical approaches but has a shorter learning curve and decreased operative time compared to laparoscopic surgery. A review of our 2-year experience showed that for the seventeen cases of HAL-N that was performed, the mean operative time was 187.8 minutes while the mean length of hospital stay was 4.1 days. For the two HAL-NU cases, the mean operative time was 415 minutes while the mean length of hospital stay was 5.5 days. Only one complication occurred and it was an incisional hernia at the hand-port site. There was no recurrence for the carcinoma cases. Our experience shows that this technique is feasible and safe.
Chromatin morphologies in human breast cancer cells treated with an anti-cancer agent are analyzed at their early stage of programmed cell death or apoptosis. The gray-level images of nuclear chromatin are modelled as random fields. We used two-dimensional isotropic generalized Cauchy field to characterize local self-similarity and global long-range dependence behaviors in the image spatial data. Generalized Cauchy field allows the description of fractal behavior inferred from fractal dimension and the long-range dependence inferred from correlation exponent to be carried out independently. We demonstrated the usefulness of locally self-similar random fields with long-range dependence for modelling chromatin condensation.
The existing clinical teaching in small group sessions is focused on the patient's disease. The main dual limitation is that not only does the clinical skill testing become secondary but there is also a slackening of student involvement as only 1 student is evaluated during the entire session. A new methodology of small group teaching being experimented shifted the focus to testing students' clinical skills with emphasise on team participation by daily evaluation of the entire team. The procedure involved was that the group underwent training sessions where the clinical skills were taught demonstrated and practiced on simulated patients (hear-see-do module). Later the entire small group, as a team, examined the patient and each student was evaluated for 1 of 5 specific tasks--history taking, general examination, systemic examination, discussion and case write-up. Out of 170 students, 69 students (study) and 101 students (control) were randomly chosen and trained according to the new and existing methods respectively. Senior faculty (who were blinded as to which method of teaching the student underwent) evaluated all the students. The marks obtained at 2 examinations were tabulated and compared for tests of significance using t-test. The difference in the marks obtained showed a statistically significant improvement in the study group indicating that the new module was an effective methodology of teaching. The teaching effectiveness was evaluated by student feedback regarding improvement in knowledge, clinical and communication skills and positive attitudes on a 5-point Likert scale. Psychometric analysis was very positively indicative of the success of the module.
We report our use of a superficial cervical plexus block to manage three adults who presented for drainage of dental abscesses. All patients had difficult airways related to severe trismus (preoperative inter-incisor distance < or = 1.5 cm). The first two patients, whose abcesses involved both the submandibular and submasseteric spaces, were managed with combined superficial cervical plexus and auriculotemporal nerve block. In a third patient, a superficial cervical plexus block alone was sufficient because the abscess was confined to the submandibular region. The blocks were successful in all three cases with minimal requirement for supplemental analgesia. We recommend the consideration of superficial cervical plexus block, and if necessary an auriculotemporal nerve block, for the management of selected patients with difficult airways who present for drainage of dental abcesses.
A "single-trial" signal subspace approach for extracting visual evoked potential (VEP) from the ongoing 'colored' electroencephalogram (EEG) noise is proposed. The algorithm applies the generalized eigendecomposition on the covariance matrices of the VEP and noise to transform them jointly into diagonal matrices in order to avoid a pre-whitening stage. The proposed generalized subspace approach (GSA) decomposes the corrupted VEP space into a signal subspace and noise subspace. Enhancement is achieved by removing the noise subspace and estimating the clean VEPs only from the signal subspace. The validity and effectiveness of the proposed GSA scheme in estimating the latencies of P100's (used in objective assessment of visual pathways) are evaluated using real data collected from Selayang Hospital in Kuala Lumpur. The performance of GSA is compared with the recently proposed single-trial technique called the Third Order Correlation (TOC).
This study presents a new approach to determine the significant prognosis factors in dengue patients utilizing the self-organizing map (SOM). SOM was used to visualize and determine the significant factors that can differentiate between the dengue patients and the healthy subjects. Bioimpedance analysis (BIA) parameters and symptoms/signs obtained from the 210 dengue patients during their hospitalization were used in this study. Database comprised of 329 sample (210 dengue patients and 119 healthy subjects) were used in the study. Accordingly, two maps were constructed. A total of 35 predictors (17 BIA parameters, 18 symptoms/signs) were investigated on the day of defervescence of fever. The first map was constructed based on BIA parameters while the second map utilized the symptoms and signs. The visualized results indicated that, the significant BIA prognosis factors for differentiating the dengue patients from the healthy subjects are reactance, intracellular water, ratio of the extracellular water and intracellular water, and ratio of the extracellular mass and body cell mass.
Software technology enables computerized analysis to offer second opinion in various screening and diagnostic tasks to assist the clinicians. Yet, the performance of these computerized methods for medical images is questioned by experts in CAD research, owing to the use of different databases and criteria for evaluating the computer results for comparison. This paper intends to substantiate this statement by illustrating the effects of such issues with the use of 1D physiologic data and multiple databases. For this purpose, the detection of desaturation events in Sp02 and spike events in EEG are used. This is the first time that comparison between different algorithms on a common basis is carried out on an individual effort. The appraisal for all the algorithms is made on the same databases and criteria. It is surprising to find that issues for 2/3D images concur with those found in 1D data here. In evaluating the accuracy of a new algorithm, a single independent database gives results fast. This paper reveals weaknesses of such an approach. It is hoped that the supportive evidence shown here is enough for researchers to innovate a better platform for credibility in reporting performance comparison of computerized analysis algorithms.
Extended patient monitoring has become increasingly important for detection of cardiac conditions, such as irregularities in the rhythms of the heart, while patient is practicing normal daily activity. This paper presents a design of a single lead wireless cardiac rhythm interpretive instrument that capable of capture the electrocardiogram (ECG) in digital format and transmitted to a remote base-station (i.e. PC) for storage and further interpretation. The design has achieved high quality of ECG and free of interference in the presence of motion.
Vermicomposting using Lumbricus rubellus for 49 days was conducted after 21 days of pre-composting. Three different combination of treatments were prepared with eight replicates for each treatment namely cow dung: kitchen waste in 30:70 ratio (T(1)), cow dung: coffee grounds in 30:70 ratio (T(2)), and cow dung: kitchen waste: coffee grounds in 30:35:35 ratio (T(3)). The multiplication of earthworms in terms of numbers and weight were measured at the end of vermicomposting. Consequently, only T(2) showed significant increase (from it initial stage) compared to other treatments. The presence of coffee grounds in T(2) and T(3) showed higher percentage of nutrient elements in vermicompost produced. The data reveal that coffee grounds can be decomposed through vermicomposting and help to enhance the quality of vermicompost produced rather than sole use of kitchen waste in vermicomposting.
Matched MeSH terms: Conservation of Natural Resources/methods*; Refuse Disposal/methods*
PURPOSE: To investigate the level and distribution of stresses in endodontically treated maxillary premolar teeth restored using various cavity designs of bonded all-ceramic restorations. The hypothesis tested was that the various all-ceramic approaches, including incorporating a pulp chamber extension in the restoration, had no influence on the stresses in the restored tooth unit.
METHODS: Finite element packages Patran and Abaqus were used for the stress analysis. The cavity designs investigated include: (1) inlay (I); (2) inlay with palatal cusp coverage (IPC); (3) onlay (O); (4) inlay with pulp chamber extension (IPE); (5) inlay with palatal cusp coverage and pulp chamber extension (IPCPE); and (6) onlay with pulp chamber extension (OPE).
RESULTS: In each case, tensile stresses were found to be concentrated subjacent to the occlusal fossa. Peak tensile stress and peak shear stress values along the tooth/restoration interface for IPC, O IPCPE and OPE cavity designs were found to be associated with the axiogingival line angle. Overall, the order of the various forms of restoration investigated in terms of the maximum principal stress (from greatest to lowest) was as follows: IPE > IPCPE > OPE > I > IPC > O.
We present our two year experience with a dermal regeneration template (INTEGRA) in burn reconstructive surgery for contracture release as well as a reconstructive tool for management of soft tissue loss.
A comparative study to explore the characteristics of partially and fully packed biological aerated filters (BAFs) in the removal of carbon pollutant, reveals that the partial-bed reactor can perform comparably well with the full-bed reactor. The organic removal rate was 5.34 kg COD m(-3) d(-1) at Organic Loading Rates (OLR) 5.80+/-0.31 kg COD m(-3) d(-1) for the full-bed, and 5.22 kg COD m(-3) d(-1) at OLR 5.79+/-0.29 kg COD m(-3) d(-1) for the partial-bed. In the partial-bed system, where the masses of biomass were only 41-51% of those of the full-bed, the maximum carbon removal limit was still between 5 to 6 kg COD m(-3) d(-1). At organic loadings above 5.0 kg COD m(-3) d(-1), the carbon removal capacity in both systems was limited by the mass and activity of microorganisms. The SRT in the full and partial-bed reactors was primarily controlled by the biomass loss in the effluent and during backwash operation. The SRT was reduced from 20.08 days at OLR 4.18+/-0.20 kg COD m(-3) d(-1) to 7.62 days at OLR 5.80+/-0.31 kg COD m(-3) d(-1) in the full-bed, and from 7.17 days to 4.21 days in the partial-bed. After all, SRT values in the partial-bed were always lower than those in the full-bed.
PURPOSE OF REVIEW: Updates on developments in critical incident monitoring in anaesthesia, and assesses its role in improving patient safety.
RECENT FINDINGS: Critical incident reporting has become more widely accepted as an effective way to improve anaesthetic safety, and has continued to highlight the importance of human errors and system failures. The establishment of an international database also improves critical incident reporting. Experiences from the national reporting and learning system in the UK have provided some solutions to the many problems and criticisms faced by the critical incident reporting technique. Direct observations to detect errors are more accurate than voluntary reporting of critical incidents, and may be a promising new approach.
SUMMARY: Critical incident monitoring is a valuable tool in ensuring patient safety due to its low cost and the ability to provide a comprehensive body of detailed qualitative information. The qualitative information gathered can be used to develop strategies to prevent and manage existing problems, as well as to plan further initiatives for patient safety. Novel approaches should complement existing methods to achieve better results. The development of a culture which emphasises safety should go hand in hand with current audit activities.
Matched MeSH terms: Quality Assurance, Health Care/methods*; Risk Management/methods*
BACKGROUND: Numerous methods of age estimation have been proposed. The Demirjian method is the most frequently used, which was first applied in a French Canadian population in 1973. The Willems method is a modification of the above and was applied in a Belgian population in 2002.
OBJECTIVES: The objectives of this study were to test the applicability of the two methods, namely Demirjian and Willems, for age estimation in a Malay population, and to find the correlation between body mass index and the difference between the dental age and the chronological age.
MATERIALS AND METHODS: A cross-sectional study involving 214 boys and 214 girls, selected by a simple stratified random sampling method was carried out. The orthopantomograph was used to score the seven left mandibular teeth, and the calculated maturity score was used to obtain the Demirjian dental age. Willems dental age was estimated using the tables proposed in the Willems method. Results. The Demirjian method overestimated the age by 0.75 and 0.61 years, while the Willems method overestimated the age by 0.55 and 0.41 years among boys and girls, respectively. In boys, the body mass index was significantly correlated to the difference in age using the Willems method.
CONCLUSION: Further modification of either method is indicated for dental age estimation among the Malay population.
Matched MeSH terms: Age Determination by Teeth/methods*; Odontometry/methods*
This paper describes an image analysis technique that objectively measures skin repigmentation for the assessment of therapeutic response in vitiligo treatments. Skin pigment disorders due to the abnormality of melanin production, such as vitiligo, cause irregular pale patches of skin. The therapeutic response to treatment is repigmentation of the skin. However the repigmentation process is very slow and is only observable after a few months of treatment. Currently, there is no objective method to assess the therapeutic response of skin pigment disorder treatment, particularly for vitiligo treatment. In this work, we apply principal component analysis followed by independent component analysis to represent digital skin images in terms of melanin and haemoglobin composition respectively. Vitiligo skin areas are identified as skin areas that lack melanin (non-melanin areas). Results obtained using the technique have been verified by dermatologists. Based on 20 patients, the proposed technique effectively monitored the progression of repigmentation over a shorter time period of six weeks and can thus be used to evaluate treatment efficacy objectively and more effectively.
Matched MeSH terms: Image Processing, Computer-Assisted/methods*; Principal Component Analysis/methods*
CT angiography (CTA) is a fast examination performed with a time-optimised contrast injection to enhance the cerebral arteries. Being a new imaging modality in our hospital, evaluation of the effectiveness of 64-row multislice CTA in detecting intracranial aneurysms in ruptured subarachnoid haemorrhage (SAH) cases is necessary. We conducted a descriptive prospective study by recruiting 30 consecutively operated SAH cases from May 2005 until November 2006. CTA findings were studied by radiologist and neurosurgeon and these were compared with operative findings. The sensitivity and specificity of CTA were 94.4% and 97.2% respectively. Approximately half of the patients were scanned within four hours and operated within 24 hours. In conclusion, CTA proves to be highly sensitive and specific in the diagnosis of intracranial aneurysms in our study.
KEY WORDS: Subarachnoid haemorrhage, Intracranial aneurysm, Computed tomography (CT), CT angiography (CTA), Sarawak
This study investigated the adsorption potential of oil palm shell-based activated carbon to remove 2,4,6-trichlorophenol from aqueous solution using fixed-bed adsorption column. The effects of 2,4,6-trichlorophenol inlet concentration, feed flow rate and activated carbon bed height on the breakthrough characteristics of the adsorption system were determined. The regeneration efficiency of the oil palm shell-based activated carbon was evaluated using ethanol desorption technique. Through ethanol desorption, 96.25% of the adsorption sites could be recovered from the regenerated activated carbon.
Matched MeSH terms: Ultrafiltration/methods*; Water Purification/methods*
In this paper, the newly explored TiO(2)-Chitosan/Glass was suggested as a promising alternative material to conventional means of wastewater treatment. Characterization of TiO(2)-Chitosan/Glass photocatalyst was studied with SEM-EDX, XRD, and Fourier transform infrared spectroscopy (FTIR) analysis. The combination effect of photodegradation-adsorption process for the removal of methyl orange (MO), an acid dye of the monoazo series occur promisingly when four layers of TiO(2)-Chitosan/Glass photocatalyst was used for MO removal. Approximately, 87.0% of total MO removal was achieved. The reactive -NH(2), -OH, and metal oxide contents in the prepared photocatalyst responsible for the photodegradation-adsorption effect were confirmed by FTIR study. Similarly, MO removal behavior was well supported by SEM-EDX and XRD analysis. Significant dependence of MO removal on the TiO(2)-Chitosan loading can be explained in terms of relationship between quantum yield of photocatalytic reactions and photocatalyst structure/activity. Hence, the research work done thus far suggests a new method, having both the advantages of photodegradation-adsorption process in the abatement of various wastewater pollutants.
Matched MeSH terms: Photochemistry/methods*; Water Purification/methods*