PURPOSE: To investigate factors associated with the presence of microdot deposits or white dots (WDs) on confocal microscopy in regular soft contact lens (SCL) users.
METHODS: This cross-sectional observational study investigated changes in the cornea in regular SCL users by using an in vivo slit-scanning microscope (ConfoScan 3). Images were analyzed by noting the presence of highly reflective WDs. Factors associated with WDs were analyzed by using an unpaired t test with Welch correction.
RESULTS: There were 56 SCL wearers. Of these, a group of 10 had WDs (GWD) in various parts of the cornea. They had worn SCLs for 7 to 20 years and had a mean total duration of SCL wear of 13.6 +/- 4.4 years. Their mean age was 35.8 +/- 10.4 years. They were compared with a group of SCL wearers with no evidence of WDs (GNWD). The mean age of GNWD was 29.1 +/- 7.2 years, with a mean duration of SCL use of 8.17 +/- 5.1 years. The two groups were compared in terms of age, total duration of SCL wear (years), duration in hours per week, SCL water content (%), mean cell density in the endothelium and stroma, endothelial cell coefficient of cell size variation, and percentage of hexagonal cells. Only the duration of SCL wear was significantly associated with the presence of WDs (p=0.0042). WDs were most commonly found in the posterior stroma (n = 9). Two patients had WDs in the epithelium, with one of these having WDs in the endothelium. All patients except one with a hazy left eye scan had WDs bilaterally and symmetrically.
CONCLUSIONS: Confocal microscopy allows visualization of WDs in the corneas of Asian regular SCL users. Patients with WDs have a longer history of SCL wear. WDs may represent an early stage of corneal disease or degeneration associated with alterations in cell behavior.
Tumors are generally difficult to detect in Magnetic Resonance (MR) images as they can be of varying intensities and do not appear as clear structures on these images. This difficulty is more prominent in MR Cholangiopancreatography (MRCP), which is the MR technology using a special sequence of T2-weighted imaging to identify the biliary tract, pancreatic duct, and gallbladder in the liver region, as MRCP images are more noisy in nature and are acquired for a more focused area with too much flexibility in position orientation for convenient computer-aided diagnosis. Based on the principle that the tumor mass manifests itself as blockage of the biliary tree structure, this paper introduces a technique that uses a region growing algorithm to identify discontinuities in the biliary tree as a means to preliminary detection of a possible tumor, in a fashion similar to the visual observation used by most radiologists in making their preliminary diagnosis. Through the use of appropriate image normalization, watershed segmentation, thresholding, rule-based region growing, and region analysis, the proposed technique is shown in this paper to be successful in identifying MRCP images with liver carcinoma from those with normal liver. Acquisition standardization, interactive image selection, and optimum image orientation will further enhance the accuracy of this proposed scheme for use in aiding clinical diagnosis at medical institutions.
MeSH terms: Algorithms; Digestive System Neoplasms/diagnosis*; Humans; Cholangiopancreatography, Magnetic Resonance/methods*
Studying the genetic history of the Orang Asli of Peninsular Malaysia can provide crucial clues to the peopling of Southeast Asia as a whole. We have analyzed mitochondrial DNA (mtDNAs) control-region and coding-region markers in 447 mtDNAs from the region, including 260 Orang Asli, representative of each of the traditional groupings, the Semang, the Senoi, and the Aboriginal Malays, allowing us to test hypotheses about their origins. All of the Orang Asli groups have undergone high levels of genetic drift, but phylogeographic traces nevertheless remain of the ancestry of their maternal lineages. The Semang have a deep ancestry within the Malay Peninsula, dating to the initial settlement from Africa >50,000 years ago. The Senoi appear to be a composite group, with approximately half of the maternal lineages tracing back to the ancestors of the Semang and about half to Indochina. This is in agreement with the suggestion that they represent the descendants of early Austroasiatic speaking agriculturalists, who brought both their language and their technology to the southern part of the peninsula approximately 4,000 years ago and coalesced with the indigenous population. The Aboriginal Malays are more diverse, and although they show some connections with island Southeast Asia, as expected, they also harbor haplogroups that are either novel or rare elsewhere. Contrary to expectations, complete mtDNA genome sequences from one of these, R9b, suggest an ancestry in Indochina around the time of the Last Glacial Maximum, followed by an early-Holocene dispersal through the Malay Peninsula into island Southeast Asia.
A methodology was developed for diagnosing industrial work, which includes questionnaire, observation, measurements, data collection and statistical analysis. A survey was conducted to investigate the relationship between job satisfaction and factors that affect work design in 2 automotives manufacturing companies in Malaysia. A basic work design model was proposed. The aim of this model was to determine the factors that influence employees' perception towards their work. A set of multiple-choice questionnaires was developed and data was collected by interviewing employees at a production plant. The survey focused on job and environmental factors. The results supported the proposed model and showed that job and environmental factors were significantly related to job satisfaction. They highlighted the significant influence of age, work experience and marital status on job satisfaction. Further, environmental factors, especially the surroundings, context dependence and the building's function, also had a significant impact on job satisfaction.
To compare morphological and positional variations of the hyoid bone in unoperated infants with cleft lip and palate (CL/P) with those in noncleft infants.
The onset of menstruation is part of the maturation process. However, variability in menstrual cycle characteristics and menstrual disorders are common. The purpose of this study was to determine the menstrual characteristics of adolescent females and factors associated with it.
MeSH terms: Adolescent; Adolescent Medicine*; Adult; Age Factors; Child; Cross-Sectional Studies; Dysmenorrhea/epidemiology; Female; Health Surveys; Humans; Health Knowledge, Attitudes, Practice*; Life Style; Malaysia; Menarche; Menstruation Disturbances/ethnology; Menstruation Disturbances/epidemiology*; Premenstrual Syndrome/epidemiology; Surveys and Questionnaires; Schools; Time Factors
INTRODUCTION: The purpose of this study is to assess whether the newly-developed VBM (Medizintechnik GmbH, Sulz, Germany) laryngeal tube (LT) is able to provide adequate ventilation and oxygenation to patients with an unstable neck and require airway management. The haemodynamic responses to insertion between the two devices were also studied. We compared the LT to the laryngeal mask airway (LMA) as an alternative airway management tool in adult patients with unstable neck and who underwent intubation with manual in-line neck stabilisation.
METHODS: A randomised single-blinded prospective study was conducted involving a total of 40 American Society of Anesthesiology I and II pre-medicated patients who were divided into two groups, LT or LMA, for airway management during elective surgery. There were 20 patients for each group. After pre-oxygenation, anaesthesia was induced using intravenous (i.v.) fentanyl and i.v. propofol. The neuromuscular blockade was produced with either i.v. vecuronium or i.v. atracurium. The LT or LMA was inserted after neuromuscular blockade was confirmed using a peripheral nerve stimulator (train-of-four 1). A size 3, 4 or 5 LT or a size 3 or 4 LMA was inserted while the patient's head and neck were being stabilised by an assistant who held the sides of the neck and the mastoid processes (manual in-line stabilisation). If it was not possible to ventilate the lungs, or if end-tidal carbon dioxide and/or chest movement did not indicate a patent airway, the LT or LMA was removed. After three failed attempts, the study was terminated and the airway was secured in the most suitable manner determined by the anaesthetist. After successful placement of LT or LMA, anaesthesia was maintained with 66 percent nitrous oxide in oxygen and 2 minimum alveolar concentration sevoflurane. All patients received standard anaesthesia monitoring. The ease of insertion, the number of attempts needed to successfully secure the airway, episodes of desaturation (less than 95 percent) and end-tidal carbon dioxide at various time intervals were studied. The haemodynamic parameters such as systolic blood pressure, diastolic blood pressure, mean arterial pressure and heart rate at different time intervals were also studied.
RESULTS: The study showed a statistically significant difference in time required for successful insertion between the groups; time required for LT was 24.8 +/- 7.7 seconds and LMA was 36.1 +/- 17.3 seconds (p-value equals 0.01). Both groups had no statistical differences (p-value is greater than 0.05) in number of attempts needed to achieve a patent airway, and the successful insertion rate was 100 percent for both groups. There were also no statistical differences in the haemodynamic response to insertion and the end-tidal carbon dioxide in this study.
CONCLUSION: We conclude that, under anaesthesia, the LT was a valuable and better alternative to LMA for ventilation and airway management when the patient's head and neck are stabilised by the manual in-line method.
Radiation-induced sarcomas are well-known though uncommon potential late sequelae of radiation therapy. We report irradiation-induced osteosarcoma involving the maxilla following treatment of nasopharyngeal carcinoma in a 44-year-old man who presented with painful cheek swelling. Radiographs and computed tomography showed a large destructive lesion of the left maxilla. Diagnosis of osteosarcoma was confirmed by excision biopsy.
Nasopharyngeal carcinoma (NPC) is a common epithelial neoplasm among the Chinese populations in Southern China and South East Asia. Epstein-Barr virus (EBV) is known to be an important etiologic agent of NPC and the viral gene products are frequently detected in NPC tissues along with elevated antibody titres to the viral proteins (VCA and EA) in a majority of patients. Elevated plasma EBV DNA load is regarded as an important marker for the presence of the disease and for the monitoring of disease progression. However, other serum/plasma parameters such as the levels of certain interleukins and growth factors have also been implicated in NPC. The objectives of the present study are, 1) to investigate the correlations between plasma EBV DNA load and the levels of interleukin (IL)-6, IL-10, TGF-beta1 and SCF (steel factor) and 2) to relate these parameters to the stages of NPC and the effect of treatment.
Silica supported iron catalyst was prepared from rice husk ash (RHA) via the sol-gel technique using an aqueous solution of iron(III) salt in 3.0 M HNO3. The sample was dried at 110 degrees C and labeled as RHA-Fe. A sample of RHA-Fe was calcined at 700 degrees C for 5 h and labeled as RHA-Fe700. X-ray diffraction spectrogram showed that both RHA-Fe and RHA-Fe700 were amorphous. The SEM/EDX results showed that the metal was present as agglomerates and the Fe ions were not homogeneously distributed in RHA-Fe but RHA-Fe700 was shown to be homogeneous. The specific surface areas for RHA-Fe and RHA-Fe700 were determined by BET nitrogen adsorption studies and found to be 87.4 and 55.8 m(2) g(-1), respectively. Both catalysts showed high activity in the reaction between toluene and benzyl chloride. The mono-substituted benzyltoluene was the major product and both catalysts yielded more than 92% of the product. The GC showed that both the ortho- and para-substituted monoisomers were present in about equal quantities. The minor products consisting of 16 di-substituted isomers were also observed in the GC-MS spectra of both catalytic products. The catalyst was found to be reusable without loss of activity and with no leaching of the metal.
Sensorineural hearing loss (SNHL) due to internal auditory canal (IAC) stenosis with hypoplasia of the cochleovestibular nerve is a rare disorder. The diagnosis of the IAC stenosis requires both high resolution computed tomography scan (HRCT) and magnetic resonance imaging (MRI).
The role of protein kinase C (PKC) in hydroxyapatite (HA)-induced phagocytosis by RAW 264.7 cells was investigated. The cells were incubated with HA particles at various incubation time and the levels of PKC activity were determined from the cell lysate. To determine the role of PKC, particles were incubated with the cells pretreated with the various concentrations of bisindolylmaleimide, a PKC inhibitor, and phagocytosis was then assessed at 60 min. Latex beads were used as a control. Our results showed that following incubation with HA particles, the levels of PKC activity in RAW264.7 cells was highest at 7 min and then decreased to reach the baseline levels of the controls at 30 min. Pretreatment of the cells with bisindolylmaleimide significantly reduced phagocytosis of HA particles in a dose-dependent pattern. The results of our present study suggest therefore that ingestion of HA by RAW264.7 cells may depend on PKC activity that may act in the early stages of phagocytosis.
MeSH terms: Animals; Cell Line; Dose-Response Relationship, Drug; Enzyme Inhibitors/pharmacology; Indoles/pharmacology; Macrophages/cytology; Macrophages/drug effects*; Macrophages/immunology; Maleimides/pharmacology; Microspheres; Phagocytosis/drug effects*; Phagocytosis/immunology; Protein Kinase C/antagonists & inhibitors; Protein Kinase C/metabolism*; Protein Kinase C/physiology; Time Factors; Durapatite/pharmacology*; Durapatite/chemistry; Mice
The use of the polymerase chain reaction (PCR) in molecular diagnosis is now accepted worldwide and has become an essential tool in the research laboratory. In the laboratory, a rapid detection, serotyping and quantitation, one-step real-time RT-PCR assay was developed for dengue virus using TaqMan probes. In this assay, a set of forward and reverse primers were designed targeting the serotype conserved region at the NS5 gene, at the same time flanking a variable region for all four serotypes which were used to design the serotype-specific TaqMan probes. This multiplex one-step RT-PCR assay was evaluated using 376 samples collected during the year 2003. These groups included RNA from prototype dengue virus (1-4), RNA from acute serum from which dengue virus was isolated, RNA from tissue culture supernatants of dengue virus isolated, RNA from seronegative acute samples (which were culture and IgM negative) and RNA from samples of dengue IgM positive sera. The specificity of this assay was also evaluated using a panel of sera which were positive for other common tropical disease agents including herpes simplex virus, cytomegalovirus, measles virus, varicella-zoster virus, rubella virus, mumps virus, WWF, West Nile virus, Japanese encephalitis virus, S. typhi, Legionella, Leptospira, Chlamydia, and Mycoplasma. The sensitivity, specificity and real-time PCR efficiency of this assay were 89.54%, 100% and 91.5%, respectively.
Gemeprost (Cervagem) has been used widely compared with Misoprostol (Cytotec) alone in second trimester pregnancy termination. This prospective randomised trial was to evaluate the efficacy of intravaginal Misoprostol (alone) and Gemeprost in second trimester termination of pregnancy. A total of 54 women with 27 on each arm were involved. A total of 25 patients (92.6%) in the Misoprostol group and 22 patients (81.5%) in the Gemeprost group delivered within 48 h. The Misoprostol group delivered earlier, although average number of tablets required were similar. The side-effects were not significant between the two groups in fact, but there was more pyrexia in the Gemeprost group (p = 0.004). Misoprostol in second trimester termination of pregnancy is clinically as effective and less costly than the standard regimen of Gemeprost.
Gryphopsylla maxomydis n. sp. (Pygiopsyllidae), Medwayella rubrisciurae n. sp. (Pygiopsyllidae) and Macrostylophora theresae n. sp. (Ceratophyllidae) are described from endemic rodents in Sulawesi. Gryphopsylla maxomydis was collected from the murids Maxomys musschenbroekii and Paruromys dominator in Central Sulawesi (Sulawesi Tengah). However, M. musschenbroekii appears to be the true host of this flea because it has spiny pelage and G. maxomydis shows morphological adaptations for parasitizing spiny hosts including a remarkable "beak-like" structure on the head. This adatation is similar to a beak-like structure on the head of Gryphopsyllo hopkinsi (Traub) which parasitizes the spiny murid Maxomys whiteheadi in Borneo (Sabah). Medwayella rubrisciurae was collected from the large tree squirrel Rubrisciurus rubriventer in Central Sulawesi and this represents the first report of this flea genus in Sulawesi. Macrostylophora theresce was recorded from the murids Bunomys fratrorum, P. dominator and Rattus xanthurus in North Sulawesi (Sulawesi Utara); most other members of this flea genus parasitize squirrels in the Oriental and Palaearctic zoogeographical regions.
In Malaysia, about 4.5% of the Malay and Chinese populations are heterozygous carriers of beta-thalassaemia. The initial identification of rare beta-globin gene mutations by genomic sequencing will allow the development of simpler and cost-effective PCR-based techniques to complement the existing amplification refractory mutation system (ARMS) and gap-PCR used for the identification of beta-thalassaemia mutations.
Predicting the future is a dangerous undertaking at best, and not meant for the faint-hearted. However, viewing the advances in molecular medicine, genomics and proteomics, it is easy to comprehend those who believe that molecular imaging methods will open up new vistas for medical imaging. The knock on effect will impact our capacity to diagnose and treat diseases. Anatomically detectable abnormalities, which have historically been the basis of the practice of radiology, will soon be replaced by molecular imaging methods that will reflect the under expression or over expression of certain genes which occur in almost every disease. Molecular imaging can then be resorted to so that early diagnosis and characterisation of disease can offer improved specificity. Given the growing importance of molecular medicine, imagers will find it profitable to educate themselves on molecular targeting, molecular therapeutics and the role of imaging in both areas.
MeSH terms: Radiography; Radiology; Genomics; Proteomics; Early Diagnosis; Molecular Imaging; Molecular Targeted Therapy; Molecular Medicine