Search PubMed⌕ Search

Biomedical subjects

Y H Bang

Publications and source records attributed to Y H Bang.

At least 19 recordsLinked to original sources
PubMed1991

The double-eyelid operation without supratarsal fixation.

Among the considerations in the formation of the double eyelid, two factors are considered to be important. They are the levator insertion into the skin and the amount of soft tissue between the levator aponeurosis and the skin. The author assumes that the amount of soft tissue may be more importantly related to forming the double eyelid than the levator expansion. Based on this assumption, the author undertook a modified operation to create the double eyelid by removing excessive soft tissue without any fixation to the levator aponeurosis or the tarsal plate.

Adipose Tissue↗
PubMed1984

Malaria control with residual fenitrothion in Central Java, Indonesia: an operational-scale trial using both full and selective coverage treatments.

An operational-scale trial, using residual fenitrothion, for control of malaria was carried out in Central Java, Indonesia, from 1980 to 1982. Two areas, each comprising about 70 km(2) and a population of about 50 000, were treated with fenitrothion (40% water dispersible powder) at a target dosage of 2 g/m(2) for 3 cycles at 6-monthly intervals. One area was treated with full coverage (i.e., the interiors of houses and cattle shelters were sprayed to a height of 3 m) for 2 cycles, followed by a third cycle with selective coverage (i.e., the interiors of houses were sprayed with one 75 cm horizontal swath between 10 cm and 85 cm from the floor while the cattle shelters were sprayed to a height of 3 m). The other area was treated for 3 cycles with only selective coverage. While both treatment methods reduced malaria rates and vector populations to very low levels, the full coverage treatment was more rapidly effective and also reduced the Plasmodium falciparum index. However, the selective coverage treatment was 68% less expensive than full coverage and greatly reduced the degree of cholinesterase depressions among the spraymen. The trial also showed that a dosage of 1 g/m(2) with full coverage was nearly as effective as the 2 g/m(2) dosage.

Animals↗
PubMed1981

Studies on Malayan filariasis in Bengkulu (Sumatera), Indonesia with special reference to vector confirmation.

In an endemic focus of Brugia malayi in Bengkulu, Indonesia the microfilariae rate was 25%. The microfilariae showed nocturnal periodicity. Domestic cats in the same area were found to harbour B. pahangi, with a microfilariae rate of 23%. In the study area, the most prevalent man-biting Mansonia mosquitoes were Mn.bonneae (41%), followed by Mn.annulata (27%), Mn.uniformis (25%) and Mn.dives (7%). More Mansonia mosquitoes were collected outdoors than indoors between 1800-2200 hours. Natural infections with infective larvae of Brugia spp. were found in Mn.bonneae, Mn.dives, Mn.uniformis, Mn.annulata, and An.nigerrimus. Experimental infection studies revealed that Mn.annulata, Mn.bonneae, Mn.uniformis, An.nigerrimus and An.peditaeniatus permit the development of infective larvae. Under experimental condition, the vectorial competence is high in Mn.bonneae, intermediate in Mn.uniformis and low in An.hyrcanus group. It is concluded that the principal vectors of periodic B.malayi in the study area in Bengkulu are four Mansonia species (Mn.annulata, Mn.bonneae, Mn.uniformis and Mn.dives), and that the potential vectors include two Anopheles species (An.nigerrimus and An.peditaeniatus). This is the first record of Mn.bonneae being a vector of periodic B.malayi in Indonesia.

Adolescent↗
PubMed1981

Prevalence of larvae of potential yellow fever vectors in domestic water containers in south-east Nigeria.

The seasonal variation in prevalence of Aedes (Stegomyia) mosquitos breeding in peridomestic water containers was assessed in an urban quarter of Enugu, Nigeria, and in two rural villages located among forest relicts in the neighbouring Udi Hills. A large number of earthenware pots, most of which contained water in the wet season, were present in the compounds around houses. Monthly determinations of the presence or absence of Aedes larvae in these containers were made for 13 consecutive months. The average Breteau index (positive containers per 100 houses) for A. aegypti during the 7-month wet season was 53 in one of the villages and 76 in the other, suggesting a high risk of yellow fever transmission; the dry-season averages were 11 and 23. In the urban quarter the wet-season average was 29; the dry-season average was 4.7, a level at which transmission is unlikely to occur. A. luteocephalus were occasionally found in containers in both the urban and rural localities, and A. africanus larvae occurred in one of the villages. Although Culex larvae were common, mixed infestations of Aedes and Culex were so uncommon that the simplified "single larva" method of sampling for Aedes gave similar results to the conventional method. The multiplicity of peridomestic containers in this part of Nigeria made the container index inadequate as a measure of larval density.

Aedes↗
PubMed1981

Progress in malaria vector control.

Malaria control, except in tropical Africa, will probably continue to be based to a large extent on the use of insecticides for many years. However, the development of resistance to insecticides in the vectors has caused serious difficulties and it is necessary to change the strategy of insecticide use to maximize their efficacy. A thorough knowledge of the ecology and behaviour of each vector species is required before the control strategy can be adapted to different epidemiological situations. The behavioural differences between sibling species have been recognized for several years, but study of this problem has recently been simplified by improved means of identification that involve chromosomal banding patterns and electrophoretic analysis. Behavioural differences have also been associated with certain chromosomal rearrangements.New records of insecticide resistance among anophelines continue to appear and the impact of this on antimalaria operations has been seriously felt in Central America (multi-resistance in Anopheles albimanus), Turkey (A. sacharovi), India and several Asian countries (A. culicifacies and A. stephensi), and some other countries. Work continues on the screening and testing of newer insecticides that can be used as alternatives, but DDT, malathion, temephos, fenitrothion, and propoxur continue to be used as the main insecticides in many malaria control projects. The search for simpler and innovative approaches to insecticide application also continues.Biological control of vectors is receiving increased attention, as it could become an important component of integrated vector control strategies, and most progress has been made with the spore-forming bacterium, serotype H-14 of Bacillus thuringiensis. Larvivorous fish such as Gambusia spp. and Poecilia spp. continue to be used in some programmes.Application of environmental management measures, such as source reduction, source elimination, flushing of drainage and irrigation channels, and intermittent irrigation have been re-examined and currently a great deal of interest is being shown in these approaches.There has been limited interest in the genetic control of mosquitos and the phenomenon of refractoriness in some strains of the disease vectors, with the idea of replacing the vector species with the refractory strain. More research is needed before this approach can become a practical tool.It is apparent that in future a more integrated approach will have to be used for vector control within the context of antimalaria programmes. Training of staff, research, and cooperation at all levels will be an essential requirement for this approach.

Animals↗
PubMed1980

A study of small mammals in the Ciloto field station area, West Java, Indonesia, with special reference to vectors of plague and scrub typhus.

From June 1977 to June 1978 a study of smal mammals was carried out in the Ciloto field station area, West Java, Indonesia by the WHO Vector Biology and Control Research Unit-II. The objectives of the investigations were to determine the diversity and density of rodent species, to find potential plague and scrub typhus vectors and to study their host-parasite relationships. In the 13 month period a total of 6 species of murids were identified; two species of campestral rats (R. tiomanicus and R. argentiventer), one species of peri-domestic (R. exulans), one species of domestic (R.r. diardii), and two species of forest rats (R. bartelsii and R. bukit). In addition, three species of insectivores (Suncus murinus, Hylomys suillus and Crocidura monticola), and one species of carnivore were found. Of the three habitats studies (mixed, ricefield and lalang), 10 species of small mammals were found in the mixed while four species of commensal murids were found in both the ricefield and the lalang. Of the four commensal murid species R. exulans had the highest density. R. tiomanicus was common but not abundant, and least common was R. argentiventer. R.r. diardii was occasionally found in the field. The mean litter size of gravid R. tiomanicus was 7.1, R. exulans 4.3, R. argentiventer 7.5 and R.r. diardii 9. Male R. tiomanicus, R. argentiventer and R.r. diardii with spermatozoa present in animals over 55 gm. Animals of less than 50 gm had no sperm. In R. exulans spermatozoa were present in specimens weighing 24-66 gm. No sperm were detected in those below 20 gm. The flea index of Xenopsylla cheopis and Stivalius cognatus as determined for R. tiomanicus was 0.3 and 2.3;l for R.r. diardii 2.2 and 1.7; for R. exulans 0.3 and 0.5; and for R. argentiventer 0.4 and 1.7 respectively. S. cognatus had a significantly higher density than X. cheopis among the campestral and peridomestic rats, but the density of X. cheopis was significantly in the domestic rat. Overall infestation rates were equally high in both mixed and lalang habitats, but low in the ricefield. Flea indices were highest in the mixed habitat, lower in lalang, and lowest in ricefield. The putative vector of scrub typhus (Leptotrombidium (L.) deliense) was quite prevalent on campestral rats, less so on domestic ones and least on peridomestic. Overall infestation rates were equally high in both mixed and lalang habitats and low in the ricefield. Chiggers load per animal was significantly higher in the mixed habitat, lower in lalang and lowest in the ricefield.

Animals↗