Aerobic granular sludge has a number of advantages over conventional activated sludge flocs, such as cohesive and strong matrix, fast settling characteristic, high biomass retention and ability to withstand high organic loadings, all aspects leading towards a compact reactor system. Still there are very few studies on the strength of aerobic granules. A procedure that has been used previously for anaerobic granular sludge strength analysis was adapted and used in this study. A new coefficient was introduced, called a stability coefficient (S), to quantify the strength of the aerobic granules. Indicators were also developed based on the strength analysis results, in order to categorize aerobic granules into three levels of strength, i.e. very strong (very stable), strong (stable) and not strong (not stable). The results indicated that aerobic granules grown on acetate were stronger (high density: >150 g T SSL(-1) and low S value: 5%) than granules developed on sewage as influent. A lower value of S indicates a higher stability of the granules.
Soil phosphorus (P) release capability could be assessed through the degree of P saturation (DPS). Our main objective was to determine DPS and, hence, P threshold DPS values of an Ultisol treated with triple superphosphate (TSP), Gafsa phosphate rocks (GPR), or Christmas Island phosphate rocks (CIPR), plus or minus manure. P release was determined by the iron oxide-impregnated paper strip (strip P), while DPS was determined from ammonium oxalate-extractable aluminum (Al), iron (Fe), and P. Soils were sampled from a closed incubation study involving soils treated with TSP, GPR, and CIPR at 0-400 mg P kg-1, and a field study where soils were fertilized with the same P sources at 100-300 kg P ha-1 plus or minus manure. The DPS was significantly influenced by P source x P rate, P source x manure (incubated soils), and by P source x P rate x time (field-sampled soils). Incubated soil results indicated that both initial P and total strip P were related to DPS by exponential functions: initial strip P = 1.38exp0.18DPS, R2 = 0.82** and total strip P = 8.01exp0.13DPS, R2 = 0.65**. Initial strip P was linearly related to total P; total P = 2.45, initial P + 8.41, R2 = 0.85**. The threshold DPS value established was about 22% (incubated soil). Field soils had lower DPS values <12% and strip P was related to initial DPS and average DPS in exponential functions: strip P = 2.6exp0.44DPS, R2 = 0.77** and strip P = 1.1DPS2 ¨C 2.4DPS + 6.2, R2 = 0.58**, respectively. The threshold values were both approximately equal to 8% and P release was 11-14 mg P kg-1. Results are evident that DPS can be used to predict P release, but the threshold values are environmentally sensitive; hence, recommendations should be based on field trials.
A total of 136 patients, 67 HIV, 69 diabetes mellitus (DM) with or without (+/-) end-stage renal disease (ESRD), were registered for tuberculosis treatment at the National Tuberculosis Center (NTBC) from May to December, 2003. Ages ranged from 21-78 years (median 57.7 years) in TB/DM patients, and 21-62 (mean 37.6 +/- 8.3 years) in TB/HIV patients. TB was significantly found in younger and single HIV patients, but in older and married DM patients (p<0.05). Male patients in both groups were strongly associated with TB, while females more commonly had TB with DM (p<0.05). The majority of these patients were Malays, unemployed, and resided in Kuala Lumpur territory; however, no statistically significant difference was found between the 2 groups. Smoking, IVDUs and hepatitis C virus (HCV) infection were more significantly found in TB/HIV patients and further analysis showed that pulmonary TB was strongly associated with HCV infection in these patients (p<0.05). Pulmonary TB (62; 89.9%) was the most common type found in both groups and was a markedly more common disease location in TB/DM patients, while extrapulmonary TB (21; 31.3%) and miliary TB (14; 21%) were significantly higher in TB/HIV patients. Cough with or without sputum, fever and loss of appetite and/or weight were common clinical presentations in both groups. Nevertheless, fever (54; 80.6%) and lymphadenopathy (17; 25.4%) were significantly related to TB/HIV patients (p<0.05). Interestingly, the presence of BCG vaccination and positive tuberculin skin test were stronger in TB/HIV (27; 40.3%) and TB/DM (20; 29%) patients, respectively (p<0.05). Overall, regular 6-, 9- and 12-months' anti-tubercular therapy (ATT) were routine practice, and EHRZ+B6 was the most common regimen used. The highest percentage of patients with treatment success were in both groups with 6 months' ATT; however, a significantly higher percentage was found in TB/DM (24; 34.8%) than TB/HIV (13; 19.4%) (p<0.05). A success rate of 15 (21.7%) was noted for TB/DM patients with 9 months' ATT, which was similar to both groups with the 12-month regimen. A higher percentage failure rate (lost to follow-up) was seen in TB/HIV (19; 28.4%) patients. Nine patients were reported to have anti-tubercular-drug side-effects, such as drug-induced hepatitis, blurred vision, and skin rash. No cases of drug resistance or death were notified among these patients.
Aerobic granular sludge (AGS) technology has been extensively studied recently to improve sludge settling and behaviour in activated sludge systems. The main advantage is that aerobic granular sludge (AGS) can settle very fast in a reactor or clarifier because AGS is compact and has strong structure. It also has good settleability and a high capacity for biomass retention. Several experimental works have been conducted in this study to observe the settling behaviours of AGS. The study thus has two aims: (1) to compare the settling profile of AGS with other sludge flocs and (2) to observe the influence of mechanical mixing and design of the reactor to the settleability of AGS. The first experimental outcome shows that AGS settles after less than 5 min in a depth of 0.4 m compared to other sludge flocs (from sequencing batch reactor, conventional activated sludge and extended aeration) which takes more than 30 min. This study also shows that the turbulence from the mixing mechanism and shear in the reactor provides an insignificant effect on the AGS settling velocity.
This retrospective and descriptive study was a report on the clinical situation of tuberculosis in diabetic patients, with 1,651 patients recruited. The mean age of TBDM patients was significantly higher than that of non-diabetic patients (p<0.05). Moreover, TBDM patients had a higher ratio of male to female than the other group. The significant proportion of TB appeared to increase steadily with age in diabetic patients compared to non-diabetic ones (p<0.05). However, they showed similarities in terms of sex, race, marital status, present address, and occupation. A higher percentage of pulmonary tuberculosis (91.4%) was shown in the TBDM group. We found that both groups had no differences in the radiological findings, with opacity or cavity of the upper lobe involvement being 89% and 91% in TBDM and non-diabetic groups, respectively. TBDM patients were shown to have more treatment success (33.3%), particularly the pulmonary type of tuberculosis in the longer duration ( 9 months). Further findings demonstrated that a lower proportion of the TBDM group defaulted in their treatment (19.8%) and experienced resistance to anti-tubercular therapy (1.4%) compared to non-diabetics.
Filariasis, a parasitic infection endemic in parts of India, Myanmar, islands of the South Pacific, West and East Africa and Saudi Arabia can be diagnosed from various types of cytopathological specimens. This case documents the detection of filarial infection from hydrocele fluid cytology in a 30-year-old Myanmar migrant worker in Malaysia.
Due to the 1997/98 haze problem in South-East Asia and the increasing need for sustainable food production and development, the usual management of crop residues (including pineapple wastes) through burning is prohibited. As a result, the need for alternative uses of pineapple wastes in pineapple production has been emphasized. This study investigated an environmentally friendly means of recycling pineapple leaves for agricultural use. Pineapple leaves were shredded and composted in a composting drum for 30 days. Part of the shredded leaves was ashed in a muffle furnace for 4 h. Humic acid (HA), K-fulvate, and K in HA and compost were analyzed using standard procedures. An ash to water ratio of 1:7 was used to extract 0.1 molar (M) KOH from the shredded leaves. The 0.1 M KOH contained 50% K and was able to extract 20% HA from the composted pineapple leaves. Percent K in the fulvate using 0.1 M KOH was 43. Besides serving as a foliar spray (supplement soil application K fertilizers), source of K for freshwater fish (e.g., tilapia), the HA produced can be used as a soil conditioner. Studies show that between 0.05-0.01 g of HA per kg soil retards runoff by 36% in sandy and sandy loam soils. The K-fulvate can be used as a fluid fertilizer. In addition, the pH of 2 of the K-fulvate suggests it could be used to dissolve phosphate rocks, particularly those in the arid regions where high soil pH does not facilitate the dissolution of these important rocks that serve as one of the sources of phosphorus fertilizer in agriculture.
This retrospective study was conducted at the National Tuberculosis Center (NTBC) where 252 HIV-positive patients coexisting with tuberculosis (TB/HIV) were examined. We found that patients with pulmonary (PTB) and extrapulmonary tuberculosis (EPT) had similar mean age. A higher sex ratio between male to female (10.7:1) was observed in patients with PTB. The other characteristics of patients with pulmonary and extrapulmonary tuberculosis were not statistically different from each other. Cough (88%) and hemoptysis were the most common presenting symptoms, significantly related to patients with PTB. Lymphadenopathy (33.5%) was the most common sign in patients with EPT. The majority of patients with pulmonary and extrapulmonary tuberculosis had CD4 cell counts of less than 200 cells/mm3 (range 0-1,179 with a median of 57 cells/mm3). Lung (89%) and miliary (55.6%) forms were the most frequent disease locations in patients with PTB and EPT, respectively. A higher percentage of patients with PTB (42%) were treated successfully with short-course (6 months) therapy, whereas in patients with EPT (43%) needed a longer period (9 months) for successful treatment. Of the patients who defaulted treatment, a higher proportion (87%) had PTB. No MDR-TB or relapse cases were found in this study.
In this retrospective study, we investigated 263 foreign patients who were diagnosed as having tuberculosis at the National Tuberculosis Center (NTBC) from January 2001 to December 2002. The age range was 14-72 years, with a mean of 33.3 +/- 9.95 years. The study subjects were predominantly males (60%) and females comprised 40%, where the greater impact of tuberculosis was observed in the young and active ones (up to 34 years of age), than middle-age (up to 54). A significantly higher percentage of these patients were from the Southeast Asian countries (87%) and particularly occurred in single male (47.5%) and married female (71.4%) patients (p<0.05). We also found that tuberculosis was significantly higher in female (50.5%) and male (64%) with smoking laborers (p<0.05). Fever (70%), cough (90.5%) and BCG vaccination status showed a significantly higher percentage in male patients (p<0.05), whereas lymphadenopathy (22%) was found in a significantly higher percentage in females (p<0.05). Overall, pulmonary disease (94.3%) occurred more commonly in males and the pleura (3.2%) was the most common site of disseminated tuberculosis. By contrast, the lymph node (11.4%) and miliary (4.8%) forms were the more common extrapulmonary tuberculosis in females. More males had higher percentage of treatment completed at > or = 6 (38%) and > or = 9 (13.3%) months in pulmonary tuberculosis, whilst, more females showed higher percentage of treatment completed (8.7%) in extrapulmonary tuberculosis. Surprisingly, more women showed non-compliance to the anti-tubercular therapy than their counterpart in this study.
During a 2-year retrospective study, 195 non-HIV-infected patients with extrapulmonary tuberculosis (EPT) were diagnosed at the National Tuberculosis Center, Kuala Lumpur, representing 10% of all patients with tuberculosis. Their mean age was 39 (+/- SD) 14 years old (range 14-81). The largest age group was 25-34 years, while 78.5% were less than 50 years of age. The subjects were mainly female (50.3%), Malay (49.2%), married (61.5%), resided in Kuala Lumpur (51.0%), and were unemployed (50.3%). Regarding risk factors, they were smokers and/or alcohol users (21.0%), and injecting drug users (IDUs) (5.1%); they also had history of tuberculosis (3.6%) and contact with TB patients (9.2%). Lymphadenopathy was the most common sign (45.6%) shown in the medical records. 42% of x-ray findings (chest, spine, and hip) showed signs consistent with tuberculosis, while histopathology was the most useful diagnostic tool (52.3%) and lymph node was the most frequent specimen used (35.0%) in this study. The three main sites of involvement were lymph nodes (42.6%), miliary and disseminated (19.5%), and pleura (12.8%). The outcome of this study showed 72.8% of these patients had completed treatment for at least 6 months, whilst, only 4.6% of patients were still undergoing treatment, and unfortunately, 22.6% of them showed non-adherence to anti-tubercular therapy at a duration of less than 6 months. However, no MDR-TB or death cases were reported or registered in this study.
Over a period of ten years (1983-1992), 134 malaria cases admitted to University Hospital, Kuala Lumpur (UHKL) were analysed. Malays constituted 27.6%, Chinese 29.8%, Indians 9.7%, Indonesians 16.4% and other foreigners 16.4%. Therefore, of the total number of cases, foreigners constituted 32.8% (44) of all the malaria cases admitted to UHKL. Fifteen of these foreigners had chloroquine-resistant strains of malarial parasites. Three species of malaria were reported of which Plasmodium falciparum constituted the most (46.3%) (80% of these developed resistance to chloroquine). Plasmodium vivax was confirmed in 44.8% (10% of these developed resistance to chloroquine) and there was only one case of Plasmodium malarie infection.
Acanthamoeba sp. is a free-living amoeba known to cause chronic central nervous system infection or eye infection in humans. Many cases remain undetected for want of a good detection system. We report for the first time a rapid staining method to facilitate the identification of Acanthamoeba sp. using the modified Field's staining technique. A. castellanii, which was used in the present experiment, is maintained in our laboratory in mycological peptone medium (Gibco). The cultures were pooled together and smears were made on glass slides for staining purposes. Different types of stains such as Field's stain, modified Field's stain, Wright's stain, Giemsa stain, Ziehl-Neelsen stain, and trichrome stain were used to determine the best stain for the identification of this amoeba. The concentration of various stains and the duration of staining were varied to provide the best color and contrast for each stain. Acanthamoeba was also obtained from the brain of experimentally infected mice and was stained with various stains as mentioned above to determine the best stain for use in identifying the presence of this parasite in experimentally infected animals. The modified Field's stain gives a very good color contrast as compared with other stains. Furthermore, it takes only 20 s to be carried out using the least number of reagents, making it suitable for both laboratory and field use.
BACKGROUND: The larva of Toxocara spp., a common animal roundworm, may infect non-compatible hosts, causing a profound immunological reaction with marked eosinophil and IgE responses, not unlike in atopy. In this study, we determined the seroprevalence of Toxocara exposure in 66 asthmatic and 58 non-asthmatic children.
METHODS: Exposure to Toxocara was determined by examining the serum samples of the children for specific IgG antibodies to L2 Toxocara larvae, using a commercially available diagnostic kit.
RESULTS: There was no significant difference in the mean age, sex, social class, residence type and presence of domestic pets at home between the two children groups. Children with bronchial asthma were observed to have higher Toxocara seropositivity than that of the non-asthmatic controls (21.2 vs 8.6%, P=0.047).
CONCLUSION: The observed relationship between exposure to Toxocara infection and bronchial asthma in Malaysian children warrants further evaluation. An understanding of any possible contribution to the pathogenesis of childhood asthma provides a potential avenue for prevention.
Study site: Paediatric Asthma clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia
A total of 290 HIV/AIDS patients were recruited into this retrospective study, which was carried out at the National Tuberculosis Center (NTBC), Kuala Lumpur. The age range was 18 to 75 years with a mean age of 36.10 (SD +/- 7.44) years. Males outnumbered females by a ratio of 31:1. In this study, the majority of patients were male (96.9%), Malay (47.2%), single (66.9%), unemployed (81%), and smoked (61.4%). The main risk marker identified was injecting drug use (74.5%). The most common clinical manifestations were cough, fever, sputum, lymphadenopathy, and chest infiltrations. More than half of the patients (85.9%) were diagnosed with localized tuberculosis (pulmonary) and the others (14.1%) had extra-pulmonary or disseminated tuberculosis. At the time of this study, the majority of the patients (16.9%) had CD4 cell counts of less than 200 cell/mm3, with a median of 221 cell/mm3. Clinical outcomes demonstrated that among those who survived, 11.0% and 20.7% of the patients had completed treatment either > or = 6 or > or = 9 months, respectively, whereas 54.8% of patients were lost to follow-up, including 0.7% for MDR-TB. Diagnostic criteria for tuberculosis in this study were mainly clinical symptoms/signs and chest x-ray findings (31.0%).
Stool examination, height and weight measurements were undertaken on 249 early primary school children at two schools in North-eastern Peninsular Malaysia. Helminth infected children were treated and follow-up anthropometric measurements and stool examination undertaken on all (n = 100) children at one of the schools 16 months later; to observe the relationship between acquisition of infection and growth. Baseline Ascaris prevalence rates at the two schools were 16.0% (23/144) and 47.6% (50/105) respectively whilst Trichuris rates were 33.3% (48/144) and 52.4% (55/105). Hookworm infection was uncommon. There was no difference in weight or height for age between infected and uninfected children at any time. Acquisition of worm infection over the initial 16 month follow-up period was not associated with significant decreases in growth rates. However the small subsets of children with heavy Ascaris infection were consistently lighter and shorter at all evaluation times. They also gained significantly less weight and tended to have reduced linear growth rates between measurements. Further interventional studies are required to determine if this association is one of cause and effect or largely incidental.
Sera from fifty subjects with different presentations of Brugian filariasis and from common soil-transmitted helminth infections were tested for specific anti-filarial IgG and its subclasses. Anti-filarial IgG, IgG1 and IgG3 showed cross-reactivities with soil-transmitted helminthic infections and no significant differences in optical densities among the various groups of filarial patients. In comparison with other groups of subjects, IgG4-ELISA of sera from microfilaraemic patients and some previously microfilaraemic patients showed a significant increase in optical density readings, while IgG2-ELISA showed elevated optical density readings in sera of patients with chronic elephantiasis. Therefore IgG2-ELISA is potentially useful in the diagnosis of brugian chronic elephantiasis while IgG4-ELISA may be beneficial for follow-up diagnosis of treated microfilaraemic patients.
Intestinal permeability of 246 early primary schoolchildren at 2 schools (106 of whom were infected with intestinal helminths) was assessed by using the lactulose/mannitol differential absorption test. The ratio of the urinary recoveries of lactulose and mannitol was determined after oral administration of a standard solution of the 2 sugars. Assessment of intestinal permeability was repeated on 100 infected children after treatment and on a cohort of 68 uninfected children. Infected and uninfected groups were compared with respect to baseline lactulose/mannitol ratio (L/M1) and change in lactulose/mannitol ratio between assessments (delta L/M). The correlations between baseline intensity of infection and L/M1, and between fall in intensity and delta L/M, were evaluated. Based on a crude index of socioeconomic status, each child was assigned to one of 3 socioeconomic groups; all but 3 children belonged to either groups 2 or 3. Trichuris trichiura and Ascaris lumbricoides were the 2 predominant infections; the hookworm infection rate was relatively low. The results suggested that helminthiasis exerted only a marginal effect on intestinal permeability, the impact of which in children from lower socioeconomic backgrounds was negligible in comparison with the cumulative effects of other factors.
Stool examination of 249 early primary schoolchildren at 2 schools in north-eastern peninsular Malaysia revealed that 73 were infected with Ascaris lumbricoides, 103 with Trichuris trichiura, and 18 with hookworms. Infected children were treated with a single dose of 400 mg of albendazole. The school attendance records during a 60 d period before treatment and 2 consecutive 60 d periods after treatment were examined. The absenteeism rate did not improve more among infected children after treatment than it did among the uninfected control children. The correlation between worm intensity and the number of lost school-days was poor. There was no evidence that intestinal helminthiasis caused school absenteeism among this group of children.