Allergy to Dermatophagoides pteronyssinus was determined in 61 rhinitis patients using prick test (PT), enzyme-immunoassay (EIA) and enzyme-linked immunosorbent assay (ELISA). A total of 43 patients tested positive with PT. Forty six patients were positive when tested with EIA and ELISA. With PT as standard test, EIA was found to have 83.7% sensitivity and 44.4% specificity; ELISA had 81.4% sensitivity and 38.9% specificity. There was a linear relationship between absorbance values obtained by EIA and ELISA. The performance time was 8 hours, 24 hours and 30 minutes for ELISA, EIA and PT respectively. The cost per test for ELISA, EIA and PT was US$ 0.20, US$ 5.20 and US$ 0.14 respectively. It was concluded that ELISA was more cost-effective than EIA should be used to supplement PT for a more complete diagnosis of allergy.
The sugar content of twenty-four liquid medicines commonly prescribed for infants and young children were measured and the type of sugars present were also identified in four randomly selected samples. All the liquid medicines tested contained sugar, in the range of 29.4% to 61.2%. Sucrose appeared to be the most commonly used sugar. Whilst it is agreed that sucrose makes the medicine more acceptable to children, its continual use by the pharmaceutical industry should be discontinued due to its harmful effect on the dental health of children, particularly those taking these syrup-based medicines on prolonged basis. Sugar-free alternatives such as sorbitol or saccharin should be used instead.
This is a retrospective study of 80 patients with major central and lateral middle third fractures of facial skeleton treated at University Hospital from 1981 to 1985. The most common was the fractures of zygomatic complex. The peak incidence was in the 20-29 year age group and males were involved more than females (ratio 9: 1). Road traffic accidents were to be blamed for most of the fractures which was 82.25%.
Mucosal sensitivity to chlorhexidine mouthwash is a rare occurrence and very few cases have been reported in the literature. The authors report 2 cases of oral sensitivity to chlorhexidine and discuss the side-effects, possible causes of sensitivity and the management of the cases.
Early-onset periodontitis in children, teenagers and young adults is quite rare. This form of periodontitis progresses very rapidly and cause massive destruction to the periodontium. Various names have been given to this condition since it was first recognised in the 1920s. Through time the nomenclature changed from one to the other. Currently 3 forms of early-onset periodontitis are recognised--i.e. prepubertal periodontitis (PPP), localised juvenile periodontitis (LJP) and rapidly progressive periodontitis (RPP). The clinical features of juvenile periodontitis as it was first described together with that of the present 3 clinical entities mentioned above are presented. Concepts on the aetiology of the disease have also changed through time, and include degenerative process, bacterial infection, defects in the host defense system and heredity. Current thought is that there is an interplay of most of these factors in pathogenesis of the disease. Treatment modalities changed too. At the moment, comprehensive periodontal therapy with meticulous oral hygiene measures seem to be the treatment of choice. Concurrently, systemic tetracycline administration might have some added benefits.
MeSH terms: Adolescent; Adult; Child; Humans; Oral Hygiene; Tetracyclines/therapeutic use
A case of an incomplete tooth fracture followed by a complete fracture was presented. The difficulty of diagnosing this condition was discussed as well as the possible histological explanation of the symptoms experienced by the patient. It once again points out to practising dentists, that whilst deep pockets can give rise to severe periodontal pain, intense and excruciating pain should be investigated with the cracked tooth in mind.
Delayed replantation of an avulsed tooth with an open apex resulted in failure of revascularization, necrosis of the pulp and extensive external root resorption. Removal of the necrotic pulp and repeated intra-canal dressings of calcium hydroxide over a three year period arrested the inflammatory resorptive process. The process was replaced by replacement resorption leading to ankylosis and infra-occlusion of the affected tooth. As the tooth was asymptomatic, it was retained in the arch to act as a space maintainer. To improve aesthetics, the crown was recontoured using a light-cured resin.
The mosquito, Aedes albopictus, has recently become established in a number of cities throughout the United States. An initial survey of allozyme and genotypic frequencies in U.S. populations (Black et al., 1988) revealed an extensive amount of local differentiation of populations and suggested that much genetic drift may have accompanied colonization. A study of gene flow was initiated in native habitats of Ae. albopictus in Malaysia to determine if the result observed in the U.S. was a consequence of colonization or simply followed the natural breeding structure of the species. Allelic and genotypic frequencies were monitored at ten enzymatic loci in 11 populations from peninsular Malaysia and Borneo. Multiple populations were sampled within the districts of Kuala Lumpur and Kuala Trengganu. Peninsular Malaysian and Borneo populations were strongly genetically differentiated. Allele frequencies were significantly different among and within districts in both regions. Variance in allele frequencies among all collections was partitioned into the variance among regions, districts within regions and collections within districts. Almost all of the variance within regions was attributable to local differentiation suggesting that genetic drift is an important component of the natural breeding structure of this species. This indicates that the large amounts of local differentiation found in U.S. populations was not a consequence of recent colonization.
Four recent cases of dengue fever with severe, unusual clinical manifestations are described. Two of these cases had features of fulminant hepatitis and encephalopathy; one of these cases was fatal. The two remaining cases showed hepatitis with renal impairment. The significance and importance of these unusual manifestations of dengue disease are discussed.
MeSH terms: Adolescent; Adult; Central Nervous System/physiopathology; Child; Dengue/diagnosis*; Dengue/epidemiology; Dengue/physiopathology; Female; Hepatitis/etiology; Humans; Infant; Kidney/physiopathology; Malaysia; Male
A dot enzyme immunoassay (DEIA) was used to determine the levels of antibody to dengue 3 virus in the acute and convalescent sera of febrile patients with a clinical diagnosis of dengue fever or dengue haemorrhagic fever. The antibody titres were compared with titres determined by the haemagglutination inhibition (HI) test. The results of the study showed that, besides being more simple to perform, the DEIA is in order of magnitude more sensitive than the HI test. Furthermore, the data suggest that it is possible to use a single dilution as a cutoff point to predict with reasonable accuracy, if a patient has had a recent dengue infection. The DEIA test for antibodies to dengue virus is an appropriate technology highly suitable for rapid diagnosis and surveillance in developing countries.
Until recently, very little was known of Anopheles species complexes and their relationships to epidemiology and malaria transmission in Southeast Asia. During the past eight years, extensive studies on the genetics of natural populations of anopheline mosquitoes in this region, involving the interdisciplinary efforts of taxonomists, operational entomologists and biologists, have revealed groups of cryptic species of Anopheles vectors, particularly the An. leucos phyrus group. This species group comprise seventeen species and two subspecies widely distributed in the forested areas of Southeast Asia. Among these species. An. dirus Peyton and Harrison, has been shown by cytogenetic and morphological studies to be a complex of at least seven isomorphic species, provisionally designated species A, B, C, D, E, F and takasagoensis, on the Southeast Asian mainland. Cytological identification of these species is based on distinct banding patterns of salivary gland polytene chromosomes as well as heterochromatin differences in mitotic karyotypes. The five species found in Thailand (A-D, F) exhibit distinct geographic distributions. Species A is widespread throughout Thailand except in the south. Species B had been found in sympatry with species C in southern Thailand and both seem to show north-south clinal geographic variation. Species D is common on the west side of southern Thailand and along the Thai-Burmese border in sympatry with species A. Species F, An. nemophilous Peyton and Ramalingam, has been found in a population at the Thai-Malaysian border in this study although it was known to be common in southern and western Thailand and Peninsular Malaysia. Species E is known only from western India. The five species found in Thailand also exhibit seasonal variation in relative abundance and different nocturnal biting cycles. Chromosomal polymorphisms have been observed in mitotic and polytene chromosomes of An. dirus A and D. Species B and C also show heterochromatin variation in the sex chromosomes, but are monomorphic for the standard sequence in polytene chromosomes. These biological characteristics of the An. dirus complex may have implications for understanding the epidemiology of malaria in Southeast Asia. Recent cytogenetic studies of wild-caught samples of An. leucosphyrus from Sumatra, Kalimantan and southern Thailand have revealed the presence of two distinct species within this taxon. Species A is widely distributed in southern Thailand, East Malaysia and Kalimantan, while species B is confined to Sumatra. The two isomorphic species are vectors of human malaria within their range of distribution.(ABSTRACT TRUNCATED AT 400 WORDS)
Starch-gel electrophoretic studies on nine gene-enzyme systems comprising 14 loci revealed a fair level of genetic variation in two population samples of Anopheles maculatus from Peninsular Malaysia. The proportion of polymorphic loci was 0.36 for the Fort Bertau sample and 0.29 for the Gua Musang sample, while the mean heterozygosity value was 0.09 for Fort Bertau and 0.07 for Gua Musang. The values of genetic similarity (I = 0.98) and genetic distance (D = 0.02) were of the rank of geographical populations.
Two separate observations from recent electrophoretic studies of the systematics and population genetics of laboratory-reared populations which had a long history of colonization in various laboratories, were found to be inconsistent with the present study which used wild-caught populations from East Malaysia. Reanalysis of the two data sets generally indicated a low amount of genetic variation in laboratory colonies. The latter is characterized by higher frequency of monomorphic loci, low average heterozygosity values and, in one extreme case, no variability at two loci. However, natural populations of An. balabacensis and An. leucosphyrus showed more protein variability by the use of polyacrylamide gel electrophoresis. Since laboratory-maintained mosquitoes are genetically and phenotypically different from those in the field, results of laboratory studies on the systematics and population genetics of Anopheles species complexes may be biased.