Eighteen strains of Getah virus isolated from mosquitoes, swine and horses in Japan (1956 to 1981), and one strain isolated in Malaysia (1955), were analysed by RNase T1-resistant oligonucleotide fingerprinting. All fingerprints showed a poly(A) tract. The fingerprint pattern of the Malaysian strain was quite different from those of the Japanese strains. Although most of the recent Japanese isolates shared many large oligonucleotide spots in common, the patterns were not identical even among the strains obtained in one locality in the same year. These results suggest that the Getah virus genome undergoes mutation rather frequently. However, there is a tendency for the isolates of the same year to show greater similarity. The fingerprint patterns of certain host-dependent temperature-sensitive (ts) mutants differed from that of the parental strain. Also, there were some differences in large oligonucleotide spots between strain JaNAr12380M isolated in suckling mouse brain (SMB) and strain JaNAr12380A isolated in C6/36 cells, despite the fact that both strains were derived from the same wild mosquito homogenate. In addition, many host-dependent ts mutants were present in strain JaNAr12380A, whereas no such mutants were observed in strain JaNAr12380M. It is concluded that there is considerable variation in the strains of Getah virus infecting mosquitoes in the wild, and also that the variants or mutants present in mosquitoes might be subject to selection during viral multiplication in the mammalian host.
Hemagglutination activity, structural protein profiles and neutralization assays were used in a comparative study of bovine herpesvirus 1 strains from the U.S.A., Canada, Great Britain, Denmark and Malaysia with equine, feline and human herpesviruses in order to further characterize the bovine herpesvirus 1 hemagglutinin. Bovine herpesvirus 1 strains of different geographical origins all showed hemagglutinating activity for mouse erythrocytes; furthermore, feline herpesvirus 1 was also shown to hemagglutinate mouse erythrocytes. Analyses of partly purified viruses showed that a distinctive and specific polypeptides profile is associated with each species of herpesviruses used in our study; strains of bovine herpesvirus 1 from North America, Europe and Southeast Asia however, presented a remarkable similarity as to their electrophoretic protein patterns. A protein similar to the 97-kDa bovine viral hemagglutinin was not identified with the hemagglutinating feline herpesvirus. An important neutralization epitope on the bovine viral hemagglutinin was also not found on feline, equine and human herpesviruses but was identified on all bovine strains tested from North America, Europe and Southeast Asia stressing the importance of the bovine hemagglutinin for eventual prophylactic purposes.
Laboratories intending to adopt cycle sequencing of PCR products in their routine analysis often face a confusing range of methods and kits. Through the study of mitochondrial cytochrome b, we have shown that clean and highly reproducible sequences could be obtained by using a combination of existing simple and economical methods in the preparation of DNA templates, PCR, purification of PCR products and sequencing. Our protocol is useful in itself or as a standard in typing other PCR-amplified DNA at the population level.
Milk lipids play an important role in the early nutrition of an infant's life. A study was undertaken to investigate the total lipid content of milk obtained from urban, exclusively breastfeeding Malaysian mothers offill term infants. Results from approximately 600 samples analysed using a commercial kit [MerckotestO] , showed that the total lipid concentration was lowest in colostrum [1.9 + 0.1 g/dl J, however this value increased gradually with days of lactation and attained a maximum concentration of 3.1 ± 0.1 g/dl during the mature milk stage. This agrees with results from other studies that the total lipid content is indeed influenced by the stage of lactation. The effect of socioeconomic factors such as income and parity on the milk lipids was also investi-gated and the results revealed that the above factors had no significant influence on the total lipid content of Malaysian mother 's milk obtained during all three stages of lactation studied [colostrum, transitional and mature milk] . However; ethnicity showed significant influence during the mature but not in the early [colostrum and transitional] stage of lactation. This however, is not filly explained by this study. As a whole, this study suggests that the human breast, through a mechanism that is ill understood, maintains cm optimal level of total lipid in milk despite their differing cultural and genetic background. It is hoped that such scientific evidence will instil more confidence among breastfeeding mothers in this fast developing cosmopolitan nation.
The author provides an account of the discovery of a previously undescribed disease of horses and a description of the studies involved in determining the aetiology of the disease. The causative virus, now named Hendra virus (HeV), is the reference virus for a proposed new genus within the virus family Paramyxoviridae. The virus is a lethal zoonotic agent able to cause natural disease in humans and horses and experimentally induced disease in cats, guinea-pigs and mice. The virus also naturally infects species of the family Megachiroptera, mainly subclinically, and such animals are the natural host of HeV. The virus appears to transmit readily between species of Megachiroptera, but not readily between horses under natural and experimental conditions, or from horses to humans. The method of transmission from bats to horses is not known. Three incidents of HeV disease in horses have been recorded in Australia--two in 1994 which caused the death of two humans and fifteen horses and one in 1999 which involved the death of a single horse. Hendra virus is related to Nipah virus, the virus that caused disease and mortality in humans, pigs, dogs and cats in Malaysia during 1998 and 1999.
A pig-borne virus causing viral encephalitis amongst human beings in Malaysia was detected in 1997 by the Ministry of Health. Initially, the disease was considered to be Japanese encephalitis. Subsequently, it was thought to be a Hendra-like viral encephalitis, but on 10th April, 1999 the Minister of Health announced this mysterious and deadly virus to be a new virus named Nipah virus. The virus was characterized at CDC, Atlanta, Georgia. The gene sequencing of the enveloped virus revealed that one of the genes had 21% difference in the nucleotide sequence with about 8% difference in the amino acid sequence from Hendra virus isolated from horses in Australia in 1994. The virus was named after the village Nipah. In all, the Ministry of Health declared 101 human casualties, and 900,000 pigs were culled by April, 1999. The worst affected area in Malaysia was Negri Sembilan. The symptoms, incubation period in human being and pigs, animal to human transmission, threat of disease to other livestock, and control program adopted in Malaysia is described.
In the interval 1994-1999, in Australia, Malaysia and Singapore, epizootic and epidemiological episodes of meningoencephalitis and severe acute respiratory syndromes were reported. Highly lethal in horses, swine and humans, the episodes were proved to be caused by the "new" viruses Hendra (HeV) and Nipah (NiV). At the same time three "new" viral agents have been isolated: Lyssavirus, Menanglevirus and Tupaia paramyxovirus. The intense contemporary circulation of people, animals and food products together with changes in human ecosystem favor new relations between humans and the "natural reservoirs" of biologic agents with a pathogenic potential for domestic and peridomestic animals and humans.
Using the reverse transcription-polymerase chain reaction (RT-PCR) and direct sequencing, capsid protein and non-structural protein 1 (nsP1) regions of Sagiyama virus and eight Getah virus strains were analysed. The viruses were isolated from Malaysia and various areas of Japan over a period of 30 years. Based on the available published sequence data, oligonucleotide primers were designed for RT-PCR and the sequences were determined. Our findings showed that though there were differences in the nucleotide sequences in the nsP1 region, there was 100% amino acid homology. On the other hand, in the capsid region, the nucleotide differences caused a major difference in the amino acid sequence. Therefore, the difference in the capsid region is one of the useful markers in the genetic classification between Sagiyama virus and strains of Getah virus, and might be responsible for the serological difference in complement fixation test. The genomic differences among the Getah virus strains are due to time factor rather than geographical distribution.
Satu kajian keratan rentas telah daalanlcan ke atas kanak-lcanak yang tinggal 0.5 km dari sebuah lcuari di Sungai Siput Utara. Objelctif kajian ini ialah untulc mengkaji hubungan PM10 dengan fungsi paru-paru kanak-kanak tersebut. Seramai 51 orang kanak-/canak yang ringgal berhampiran kuari dan terdedah dengan debu kaur tehih dipilih, manakala 37 orang kanak-kanak yang tinggal berjauhan tetapi di daerah yang sama telah dipilih sebagai perbandingan untuk lag ian ini. Borang soalselidik telah digunakan untuk mendapatlcan maklumat latarbelakang dan sejarah respiratori dari ibu bapa kanalc-kanak terlibat. Fungsi paru-paru kanak-kanak pula diukur dengan menggunakan Pony Graphic S pirometer. Min kepekatan PM1 0 selama 24 jam di dalam rumah kediaman di kawasan terdedah ialah 76.66 (g/m3 dan di kawasan perbandingan 41 .55 (g/m3. Perbezaan kepekatan PM10 di antara kedua kawasan ini adalah signifikan (p=0.01). Hasil ujian fungsi paru-paru menunjukkan perbezaan yang signifikan di antara fungsi paru-paru kanalc-kanalc terdedah dengan kanak-kanak perbandingan dari segi FVC % jangkaan (t = -8.227, p = 0.01) dan FEV1 % jangkaan (t = -8.729, p = 0.01). Min fungsi paru-paru kanak-kanak lelaki di kawasan terdedah, (FVC % jangkaan = 68.05, FEV1 % jangkaan = 73.71) adalah lebih rendah daripada kawasan perbandingan (FVC % jangkaan= 89.78, FEV1 %~ jangkaan = 86.97). Min fungsi paru-paru kanak-kanak perempuan di kawasan terdedah (FVC % jangkaan= 69.64, FEV1 % jangkaan =74.90) juga adalah lebih rendah daripada hawasan perbandingan ( F VC % jangkaan = 90.99, FEV1 % jangkaan : 87 .7 9). Prevalens kejejasan parurparu FVC % jangkaan l
Three newly recognized encephalitogenic zoonotic viruses spread from fruit bats of the genus Pteropus (order Chiroptera, suborder Megachiroptera) have been recognised over the past decade. These are: Hendra virus, formerly named equine morbillivirus, which was responsible for an outbreak of disease in horses and humans in Brisbane, Australia, in 1994; Australian bat lyssavirus, the cause of a severe acute encephalitis, in 1996; and Nipah virus, the cause of a major outbreak of encephalitis and pulmonary disease in domestic pigs and people in peninsula Malaysia in 1999. Hendra and Nipah viruses have been shown to be the first two members of a new genus, Henipavirus, in the family Paramyxoviridae, subfamily Paramyxovirinae, whereas Australian bat lyssavirus is closely related antigenically to classical rabies virus in the genus Lyssavirus, family Rhabdoviridae, although it can be distinguished on genetic grounds. Hendra and Nipah viruses have neurological and pneumonic tropisms. The first humans and equids with Hendra virus infections died from acute respiratory disease, whereas the second human patient died from an encephalitis. With Nipah virus, the predominant clinical syndrome in humans was encephalitic rather than respiratory, whereas in pigs, the infection was characterised by acute fever with respiratory involvement with or without neurological signs. Two human infections with Australian bat lyssavirus have been reported, the clinical signs of which were consistent with classical rabies infection and included a diffuse, non-suppurative encephalitis. Many important questions remain to be answered regarding modes of transmission, pathogenesis, and geographic range of these viruses.
Objective: Previous studies have shown milk to contain cancer inhibitors. In this context, this study was conducted to screen the potential cytotoxic properties of four different types of milk, namely cow's milk, goat's milk, mare's milk and human milk.
Methods: In evaluating the cytotoxic properties of milk, two different human leukemia cell lines namely, Raji and CEM-SS were used. The treated and untreated cells of milk were cultured at 37°C in 5% CO2 for 5 days according to standard guidelines. The CellTiter 96® Aqueous (MTS) assay was carried out on the first, third and fifth days to measure cell viability. The percentage of cell viability was determined by comparing the optical density of the treated cells against the untreated controls. One-way ANOYA at p
This survey elucidated the perceptions and implementation 0f orthodontic Clinical Practice Guidelines (CPGs) by all ortlmduntistc and dental officers in the Ministry of Health Mahysia (MOH). Two different set: uf xelf-administered questionnaires were targeted at first·year dental officers (FYDO), dental officcrx (DO) and administrative Senior Dental Officers (SDO) in one group and unhocluntists in another group. Only 30% responded from a total of 1,327 MOH dental officers, with no participation from three States. Majority (89%) of officers have heard of CPG: although some were unsure of their purpose and usage. About 69% have read orthodontic CPG; of whom 87% have read other MOH dental CPG:. About 78.6% found CPGs 'gaud to excellenf but 16,0% did not answer this question. Same comments received included: language was confusing, inadequate details and pictures, need improvement, irrelevant, need CPG: for other orthodontic problems, need more knowledge first and requests for mare copies. Only 27.7% used them often, 53% occasionally and 15% hardly follow CPG:. About 82% felt that they were encouraged to use CPGx in their workplace and the majority (86%) knew where they were kept especially SDC: and DO; About 90% in the orthndonzist group have received hard copies of orthodontic CPGs but the majority (76%) has not seen them on the website. Although all felt that CPG; were useful to officers and encouraged their use, only 62.5% have introduced CPGs to their officers. There was generally more awareness and usage of CPGS among SDOs compared with DOs and FY DO; The dissemination and availability of orthodontic CPG: is reasonably good. However, the implementation by mthodontists and administrative officers can be improved for better awareness, understanding and usage by dental officers, especially FYDOs.
Paramyxoviruses have been implicated in both animal and human infections. Some viruses, such as Morbilliviruses are responsible for large-scale epidemics. However, there are limited observations of these viruses crossing the host species barrier in nature. In 1994, in Australia a fatal infection in horses and humans was identified to be caused by a new Paramyxovirus, Hendra virus (HeV), and in 1998 in Malaysia, a closely related virus, Nipah virus (NiV) was responsible for fatal infections in pigs and humans. These two viruses were sufficiently different from previously described Paramyxoviruses to create a new genus, Henipaviruses. The natural reservoir of these viruses was the fruit bat (Pteropus), which is found in regions extending from the western Pacific to the eastern coast of Africa. Serological studies have established that as many as half the fruit bats in colonies throughout these regions may have antibodies against this family of viruses. The availability of diagnostic reagents for Nipah virus in humans have identified infections in several countries including, Bangladesh, India and Indonesia. In some of these epidemics, mortality in humans exceeds 75%. Deforestation is probably responsible for fruit bats leaving their ecological niches and approaching farms and villages. The infection of humans and animals may occur via contaminated foods or in certain cases by animals to man. At present, only within close families has human-to-human transmission been proposed. Henipavirus infections are probably more widespread than it is at presently known and so it is important to have an intense monitoring for these diseases, especially in countries where large-scale deforestation is happening.
Cross neutralisation of venoms by antivenom raised against closely-related species has been well documented. The spectrum of paraspecific protection of antivenom raised against Asiatic Naja and Bungarus (krait) venoms, however, has not been fully investigated. In this study, we examined the cross neutralisation of venoms from common Southeast Asian cobras and kraits by two widely used polyvalent antivenoms produced in India: Vins Polyvalent Antivenom (VPAV) and Bharat Polyvalent Antivenom (BPAV), using both in vitro and in vivo mouse protection assays. BPAV was only moderately effective against venoms of N. kaouthia (Thailand) and N. sumatrana, and either very weakly effective or totally ineffective against the other cobra and krait venoms. VPAV, on the other hand, neutralised effectively all the Southeast Asian Naja venoms tested, as well as N. naja, B. candidus and Ophiophagus hannah venoms, but the potency ranges from effective to weakly effective. In an in vivo rodent model, VPAV also neutralised the lethality of venoms from Asiatic Naja and B. candidus. In anesthetised rat studies, both antivenoms effectively protected against the N. kaouthia venom-induced cardio-respiratory depressant and neuromuscular blocking effects. Overall, our results suggest that VPAV could be used as alternative antivenom for the treatment of elapid envenomation in Southeast Asian regions including Malaysia, Thailand and certain regions of Indonesia.