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.
The process of development in Malaysia has brought about significant socioeconomic and demographic transformations. Reduction in fertility and mortality, have resulted in increasing survival of populations to later life. Thus the proportion of the elderly is increasing. Population ageing, the most salient change affecting the demographic profile of Malaysia, will have a significant impact on the patterns of socio-economic development. In order to anticipate and respond in time to the far reaching socio-economic and humanitarian implications of ageing, it is imperative that the magnitude and the
momentum of its occurrence need to be recognised.
This paper looks at demographic trends, disease profile as well as health policy implications of ageing in Malaysia.
The effects of functional appliance treatment have been reported in numerous studies in the literature with great variability in the findings. It is generally agreed that they can be used successfully to treat Class II malocclusions in growing and cooperative patients. However, there is a lack of consensus regarding the relative orthodontic and orthopedic correction obtained by functional appliances in Class II correction. Lateral cephalometric radiographs from a sample (n = 36) of patients who had undergone a phase of treatment with activator appliances were measured and analysed for changes using a modified version of the method described by Johnston (Hashim and Godfrey 1990). In this method, the treatment changes were broken down into: tooth movement relative to basal bone; and the translatory growth of the jaws, both with respect to the cranial base and to each other. The results show that the treatment effects were mainly dentoalveolar. There was a slight orthopedic effect on the maxilla, but no significant mandibular growth was observed, above that which can be expected from normal growth.
Among a series of 101 patients bitten by sea-snakes in Malaya in the years 1957-64, 80% were fishermen. Bathers and divers are occasionally bitten. Before sea-snake antivenom became available the mortality-rate (despite the high toxicity of sea-snake venom) was only 10%; however, of 11 with serious poisoning, 6 died. Subsequently 10 patients with serious poisoning received specific sea-snake antivenom; 2 patients, admitted moribund, temporarily improved but died, and 8 patients recovered dramatically. In serious poisoning the suitable dosage of intravenous sea-snake antivenom is 3000-10,000 units; in mild poisoning 1000-2000 units should suffice.
Epidemiological features as reflected by 101 patients with unequivocal sea-snake bite received in north-west Malaya are reviewed. Enhydrina schistosa caused over half the bites, including seven of the eight fatal bites. It is the most dangerous sea-snake to man. Over 90 per cent of the victims were male and 80 of the 101 patients were fishermen bitten at their job. Most victims were bitten on the lower limb through treading on the snake, and this resulted in more cases of serious poisoning than upper limb bites (caused through handling nets, sorting fish and so on). Only 14 cathers were bitten (through treading on the sea-snake; no bathers were bitten while swimming). In patients coming to hospital more than six hours after the bite, there was a four-fold increase in serious poisoning compared with patients coming within six hours of the bite. Thus, as time elapses after the bite, the victim is less likely to seek medical help unless poisoning is severe. Despite the lethal toxicity of sea-snake venom, in patients seen during 1957-61 before sea-snake antivenom became available, the mortality was only 10 per cent. Trivial or no poisoning followed in 80 per cent of the bites. On the other hand, of 11 patients (20 per cent) with serious poisoning, over half (six patients) died despite supportive hospital treatment. These epidemiological features observed in Malaya probably apply to most fishing folk along Asian coastlines where sea-snakes abound. If this is so, sea-snake bite must be a common hazard feared by millions of fishing folk, and a common cause of illness and death. But it is unlikely that the extent of this problem will be revealed to orthodox medicine for many decades because most fishing villages are far from medical centres; and even if hospitals or medical centres are available, fishing folk are usually reluctant to attend them. Only one species of sea-snake, Pelamis platurus, extends to the east coasts of Africa and west coasts of the tropical Americas, but for various reasons this species does not appear to constitute much of a hazard to fishing folk in these areas. Although bathers are occasionally bitten along Asian coasts, when they inadvertently tread on a sea-snake, the risk of sea-snake bite in this area is extremely low. The prevention of sea-snake bite and poisoning is considered. Highly effective antivenom is now available for treating victims with serious poisoning; death should not occur provided adequate medical treatment is given within a few hours of the bite. The main problem is provision of adequate medical care at rural medical centres and overcoming the reluctance fishing folk often have in attending these centres.
Autocorrelation problem causes unduly effects on the variance of Ordinary Least Squares (OLS) estimates. Hence, it is very essential to detect the autocorrelation problem so that appropriate remedial measures can be taken. The Breusch-Godfrey (BG) test is the most popular and commonly used test for the detection of autocorrelation. Since this test is based on the OLS estimates, which are not robust, it is easily affected by outliers. In this paper, we propose a robust Breusch-Godfrey (MBG) test which is not easily affected by outliers. The results of the study indicate that the MBG test is more powerful than the BG test in the detection of autocorrelation problem.
Bladder cancer is the second most common cancer of the urinary tract, and overall it is among the top 10 cancers in men. Transitional cell carcinoma (TCC) is the most common type, with the majority being superficial disease, i.e. the tumour has not gone beyond the lamina propria. The main problem with superficial TCC is the high recurrence rate. Various forms of treatment methods have been attempted to reduce the recurrence rate, with intravesical bacillus Calmette-Guerin (BCG) being the most successful to date. In fact, intravesical BCG is one of the most successful forms of immunotherapy in the treatment of any form of cancer. This article is a general review of BCG in bladder cancer with an emphasis on the indication and mechanism of action in reducing recurrence and progression.
Enzymatic methods have been used to cleave the C- or N-terminus polyhistidine tags from histidine tagged proteins following expanded bed purification using immobilized metal affinity chromatography (IMAC). This study assesses the use of Factor Xa and a genetically engineered exopeptidase dipeptidyl aminopeptidase-1 (DAPase-1) for the removal of C-terminus and N-terminus polyhistidine tags, respectively. Model proteins consisting of maltose binding protein (MBP) having a C- or N-terminal polyhistidine tag were used. Digestion of the hexahistidine tag of MBP-His(6) by Factor Xa and HT15-MBP by DAPase-1 was successful. The time taken to complete the conversion of MBP-His(6) to MBP was 16 h, as judged by SDS-PAGE and Western blots against anti-His antibody. When the detagged protein was purified using subtractive IMAC, the yield was moderate at 71% although the overall recovery was high at 95%. Likewise, a yield of 79% and a recovery of 97% was obtained when digestion was performed with using "on-column" tag digestion. On-column tag digestion involves cleavage of histidine tag from polyhistidine tagged proteins that are still bound to the IMAC column. Digestion of an N-terminal polyhistidine tag from HT15-MBP (1 mg/mL) by the DAPase-I system was superior to the results obtained with Factor Xa with a higher yield and recovery of 99% and 95%, respectively. The digestion by DAPase-I system was faster and was complete at 5 h as opposed to 16 h for Factor Xa. The detagged MBP proteins were isolated from the digestion mixtures using a simple subtractive IMAC column procedure with the detagged protein appearing in the flowthrough and washing fractions while residual dipeptides and DAPase-I (which was engineered to exhibit a poly-His tail) were adsorbed to the column. FPLC analysis using a MonoS cation exchanger was performed to understand and monitor the progress and time course of DAPase-I digestion of HT15-MBP to MBP. Optimization of process variables such as temperature, protein concentration, and enzyme activity was developed for the DAPase-I digesting system on HT15-MBP to MBP. In short, this study proved that the use of either Factor Xa or DAPase-I for the digestion of polyhistidine tags is simple and efficient and can be carried out under mild reaction conditions.