The author describes changes in the size and characteristics of multiple-household compounds in Kelantan, Malaysia, during the period 1971-1991. It is found that "in Malay villages, multihouseholdcompounds were in earlier times...based on a bilateral residence rule in which one or more children, either male or female, would stay in the compound of their parents....A recent trend has been for more females to remain in the parental compound than males, reflecting the orientation toward independence among the males." (SUMMARY IN ENG)
A new nematode, Elaeolenchus parthenonema n. g., n. sp., is described from the palm-pollinating weevil Elaeidobius kamerunicus Faust. The new genus is placed in the Anandranematidae n. fam., which, together with the genus Anandranema Poinar et al., 1993, is characterised by nematodes having only a single autotokous generation in the insect host. This is the first report of a member of this superfamily reproducing only parthenogenetically. The development of E. parthenonema and its effect on the weevil host is discussed, along with a phylogenetic synopsis of the families of the Sphaerularioidea Lubbock 1861. The Beddingiidae n. fam. is proposed for Beddingia Blinova & Korenchenko, 1986, comprising the original Deladenus parasites of Hymenoptera that possess both free-living and parasitic amphimictic generations in their life-cycles. This family is considered to have the most primitive type of development in the superfamily.
Malaria remains a global problem in the light of chloroquine-resistant strains of Plasmodium falciparum. New compounds are needed for the development of novel antimalarial drugs. Seed, leaf, and fruit skin extracts of Lansium domesticum, a common fruit tree in South-East Asia, are used by indigenous tribes in Sabah, Malaysia for treating malaria. The skin and aqueous leaf extracts of the tree were found to reduce parasite populations of the drug sensitive strain (3D7) and the chloroquine-resistant strain (T9) of P. falciparum equally well. The skin extracts were also found to interrupt the lifecycle of the parasite. The data reported here indicate that extracts of L. domesticum are a potential source for compounds with activity towards chloroquine-resistant strains of P. falciparum.
Matched MeSH terms: Life Cycle Stages/drug effects
The objective of this study was to characterize the polypeptides associated with cysts of Blastocystis hominis. This form is believed to be infective and plays a role in parasite resistance to anti-B. hominis drugs currently used for treatment of Blastocystis associated diarrhea. Cysts were induced through in vitro culture of the parasite in complete medium supplemented with bacterial extract with trypticase, metronidazole or doxycycline. SDS-PAGE analysis showed almost similar polypeptide patterns of parasite extracts obtained from in vitro cultured parasites before and after exposure with the three supplements. Polypeptide bands at 76, 58.5, 48, 45, 40, 38, 32, 25 and 22 kDa were constantly seen in all antigenic preparations and no specific cyst-associated polypeptide was present. However, on immunoblot analysis, 3 out of 16 blastocystosis human sera identified a cyst-associated polypeptide at 60 kDa in all parasite extracts prepared from cultures with the three supplements. In addition, there were associated morphological changes detected in these parasites stained with acridine orange and observed under fluorescence microscopy. Metronidazole induced cyst forms (reddish cells) as early as 12 hours post-exposure; more cyst production (with stronger immunoblot bands) occurred after 24 hours exposure. However, cysts rupture with release and destruction of B. hominis daughters cells occurred after 48 hours exposure. Doxycycline induced less cyst-like forms at 24 hours (weaker 60 kDa band) and less destruction of the cysts (60 kDa band still present at 72 hours post exposure). Bacterial extract and trypticase also induced cysts at 12 hours with increasing numbers up to 72 hours exposure (corresponding increase in intensity of 60 kDa band from samples harvested at 12 to 72 hours post exposure) without any sign of deleterious effect on the parasite.
The ultrastructure of the odontoblast reflects the certain phases that the cell undergoes in their lifecycle. Ultrastructure studies of the odontoblasts have often been carried out using young teeth. In this study, teeth from an older individual have been used to study the odontoblasts from the crown and root area. The odontoblasts from the crown area retain their columnar shape while odontoblasts from the root area appeared to be flattened. The organelles present in the odontoblasts either from the crown or root area was observed to be reduced.
The incubation period of Spodoptera exigua (Hübner) was not influenced by the host plant, whereas larval development time and pupal period were affected. Larval development time was longest on shallot and lady's finger, followed by cabbage and long bean. Larvae did not develop beyond the first instar when fed on chilli. The pupal period was longer on lady's finger than on cabbage, shallot and long bean. Overall, adult longevity was not influenced by the host plant but there was a difference between female and male longevity among the host plants. Survival of S. exigua was affected by the host plant at the larval stage. The number of larval instars varied between 5 and 8 within and between the studied host plants. Long bean was found to be the most suitable host plant and provide the best food quality for S. exigua compared to the other host plants, as it allowed faster development, fewer larval instars and a higher survival rate.
Larvae and adults of Culex quinquefasciatus were used for the test undertaken for malathion resistant strain (F61 - F65) and permethrin resistant strain (F54 - F58). The results showed that the LC50 for both malathion (F61 - F65) and permethrin (F54 - F58) resistant Cx. quinquefasciatus increased steadily throughout the subsequent five generations, indicating a marked development of resistance. The adult female malathion resistant strain have developed a high resistance level to malathion diagnostic dosage with a resistance ratio of 9.3 to 17.9 folds of resistance compared with the susceptible Cx. quinquefasciatus. Permethrin resistance ratio remained as 1.0 folds of resistance at every generation. It was obvious that malathion resistance developed at a higher rate in adult females compared to permethrin. Enzyme-based metabolic mechanisms of insecticide resistance were investigated based on the biochemical assay principle. From the results obtained obviously shows that there is a significant difference (p < 0.05) in esterase level in both malathion and permethrin selected strains. Female malathion selected strain has the higher level of esterase activity compared to the female permethrin selected strain at (0.8 to 1.04) alpha-Na micromol/min/mg protein versus (0.15 to 0.24) alpha-Na micromol/min/mg protein respectively. This indicated increased level of non-specific esterase is playing an important role in resistance mechanism in female malathion selected strain. Permethrin selected strain exhibited non-specific esterase activity at a very low level throughout the different life stages compared to malathion selected strain. This study suggests that life stages play a predominant role in conferring malathion and permethrin resistance in Cx. quinquefasciatus.
Larvae of the Synthesiomyia nudiseta (Wulp) were collected from a decomposed human corpse at the Department of Forensic Medicine, Penang Hospital. A colony of this species was established and the eggs were collected for rearing. The developmental times, rearing temperatures, and relative humidity were recorded twice daily from the time the eggs collected until adult emergence. An average of 5 larvae were randomly collected from the rearings twice daily, warm-water killed and preserved in Kahle's solution. The larval instar stages were determined by observing the number of posterior spiracular slits and the length of the preserved larvae were measured. When the larval life cycle was completed, the accumulated developmental times were calculated. A total of 8 replicates were carried out. The temperature of the rearing room was 28.5+/-1.5 degrees Celcius while the relative humidity was within 67-85%. The total developmental time for S. nudiseta was 322+/-19 hours (13.4+/-0.8 days).
A forensic entomological study was conducted using monkey carcasses (Macaca fascicularis Raffles) that were placed in either an outdoor or indoor environment at a coastal area in Tanjung Sepat, Selangor, Malaysia during May until August 2008. We collected pupae of Chrysomya rufifacies (Marquart) from the carcasses and kept them individually. The emergence of 13 parasitic microhymenopteran, from one of the pupae occurring within a week were identified as Exoristobia philippinensis Ashmead (Hymenoptera: Encyrtidae). Another observation was made whereby a pupa of C. rufifacies was predated by a muscid larva, Ophyra spinigera (Stein). The larva squeezed into the pupa and consumed the contents. This paper report C. rufifacies as a new host record for E. philippinensis in Malaysia and highlighted the predatory behavior of O. spinigera larva in natural environment.
Even though a lot of new advanced materials have been developed nowadays, steel remains a major material in construction, automobiles, appliances, industrial machinery as well as in the nuclear industry. Due to steel easily corroded, a proper surface protection is required to avoid any failures and extended the life cycle of the components. Surface coating is an efficient and economical method to obtain desirable material surfaces properties. Hot dip aluminizing technique was utilized in this study. Experiments have been conducted on the mild steel substrates with 12mm diameter. Prior to hot dipping process, observation on grain growth at three different temperatures had also been conducted to understand the behaviour of steel under application of heat. The substrates were heated at 700ºC, 800ºC and 900ºC for 1 hour and the microstructure was analyzed. The temperature of 800C was chosen for hot dipping. The substrates were dipped into the molten aluminum maintained at temperature 800ºC for 2,4,6,8,10,15 and 20 minutes. Optical microscopy and energy dispersive X-ray spectroscopy were used in this investigation. From the microstructure observation, it showed the appearance of intermetallic layer covered by the top layer of Al on the mild steel substrate increased with the increase in dipping time ranging from 36 to 282μm. The result of EDX analysis revealed the existence of Fe and Al in form of Fe2Al5 phase for all the dipping time.
Plasmodium knowlesi is a malaria parasite of Old World monkeys and is infectious to humans. In this study Macaca fascicularis was used as a model to understand the host response to P. knowlesi using parasitological and haematological parameters. Three M. fascicularis of either sex were experimentally infected with P. knowlesi erythrocytic parasites from humans. The pre-patent period for P. knowlesi infection in M. fascicularis ranged from seven to 14 days. The parasitemia observed was 13,686-24,202 parasites per microL of blood for asexual stage and 88-264 parasites per microL of blood for sexual stage. Periodicity analysis adopted from microfilaria periodicity technique of asexual stage showed that the parasitemia peak at 17:39h while the sexual stage peaked at 02:36 h. Mathematical analysis of the data indicates that P. knowlesi gametocytes tend to display periodicity with a peak (24:00-06:00) that coincides with the peak biting activity (19:00-06:00) of the local vector, Anopheles latens. The morphology of P. knowlesi resembled P. falciparum in early trophozoite and P. malariae in late trophozoite. However, it may be distinguishable by observing the appliqué appearance of the cytoplasm and the chromatin lying inside the ring. Haematological analysis on macaques with knowlesi malaria showed clinical manifestations of hypoglycaemia, anaemia and hyperbilirubinemia. Gross examination of spleen and liver showed malaria pigments deposition in both organs.
This study examined the effects of different life stages (first, second, third, fourth, and five instars; adult females and adult males) and feeding regimes (starved and blood fed) on the active movement activity of the tropical bed bug, Cimex hemipterus (F.), under mixed-stage conditions. We used an extended arena made from Tygon tube coils and observed the movement frequency and movement distance at selected time intervals up to 120 h. The fifth instars and adult males and females showed significantly (P < 0.01) greater movement frequency compared with the other stages. The first and second instars showed limited movement (< 8 m) over the experimental period. Starved bed bugs showed greater movement frequency compared with blood-fed bed bugs, with the exception of adult females. Blood-fed adult females exhibited significantly (P < 0.01) greater movement frequency and distance compared with starved females. Blood-fed females moved up to 42.3 m over 120 h. Regression analysis between movement distance of the fifth instars and adults and the time intervals revealed a positive relationship (r2 = 0.6583; P < 0.01), suggesting that delays in bed bug control efforts will increase the risk of the greater infestation. During bed bug inspection, the presence of only late instars and adults in premises would indicate a new infestation, whereas an established infestation likely would consist of mixed stages.
Five formulated insecticides (lambda-cyhalothrin at 10 mg m⁻², bifenthrin at 50 mg m⁻², fipronil at 10 mg m⁻², fenitrothion at 50 mg m⁻², imidacloprid at 5 mg m⁻²) and one active ingredient (DDT at 500 mg m⁻²) were evaluated using a surface contact method against early and late instars and adults of two strains of the tropical bed bug, Cimex hemipterus (F.). Synergism of lambda-cyhalothrin and fipronil using piperonyl butoxide (PBO) was also assessed.
Matched MeSH terms: Life Cycle Stages/drug effects*
Seven stains were studied to determine the best color and contrast for staining the developmental stages of free living pathogenic Acanthamoeba and Naegleria species. The acid-fast bacilli stain (AFB) produced a blue color without contrast; trichrome-eosin and modified Field's showed various color contrasts; Giemsa, iron-hematoxylin, modified AFB and Gram produced only one color which distinguished the nucleus, nucleolus, cytoplasm, food- and water-vacuoles. The motile organs (acanthopodia, pseudopodia, lobopodia and flagella) were also clearly differentiated but produced a similar color as the cytoplasm. These motile organelles were first induced by incubating at 37 degrees C for at least 15 minutes and then fixing with methanol in order to preserve the protruding morphology prior to staining. The trichrome-eosin and iron-hematoxylin stains showed good color contrast for detecting all three stages, the trophozoite, cyst and flagellate; Giemsa and Gram stained the trophozoite and flagellate stages; the modified Field's and modified AFB stains stained only the trophozoite stage. Depending on the purpose, all these stains (except the AFB stain) can be used to identify the developmental stages of Acanthamoeba and Naegleria for clinical, epidemiological or public health use.
Monstrilloid copepods are protelean parasites of different groups of marine benthic invertebrates. Only their first naupliar, preadult, and adult phases are planktonic. Monstrilloids are currently represented by more than 115 nominal species contained in four genera. Its taxonomic knowledge has been hampered by nomenclatural and descriptive problems derived from their peculiar ontogeny and poor definitions of taxa. One of the most important difficulties is that of matching males to females. The only reliable methods to link the sexes of a species are the confirmation of particular apomorphies shared by both sexes, finding both sexes in the same host or as a pre-copulatory male-female pair in the plankton, or by the use of molecular markers. A general overview of the morphology of the group and its life cycle is provided herein. Recently, upgraded descriptive standards have been established and the relevance of redescribing taxa based on type and museum specimens has been demonstrated. The rate of species description per decade has had several peaks between 1840 and 2010: (1971-1980, 1991-2000, 2001-2010), each related to the activity of a few researchers. An analysis of the world distribution of published records of the Monstrilloida revealed that the Northeast Atlantic is the best studied region (45% of all records), followed by the Northwestern Atlantic (17%); the least surveyed areas include regions of the southern hemisphere (less than 3%). The Northeast Atlantic region harbors the highest number of known species (32 nominal species), followed by the Caribbean Sea/Gulf of Mexico (24), the Mediterranean/Black Sea (19), Indonesia-Malaysia-Philippines region (17), Japanese waters (17), and the Brazil-Argentina area (16). Other than these generalized patterns, little can be concluded concerning the biogeography of the group. Many species records are doubtful or improbable, and purportedly cosmopolitan nominal species are being revealed as species complexes yet to be studied.
The life history characteristics of the rove beetle Paederus fuscipes Curtis were studied under laboratory conditions using three field strains from Malaysia: Desa Wawasan (DW), Sri Pinang (SP), and Ampang Jajar (AJ). The total development time of immature stages differed significantly among the three strains, especially between DW (17.43 +/- 0.16 d), SP (18.60 +/- 0.19 d), and AJ (18.68 +/- 0.22 d). Adult females and males from DW also exhibited a shorter life span, although the difference among strains was not significant. In terms of fecundity, the numbers of eggs laid per female for DW, SP, and AJ were 121.28 +/- 15.98, 127.30 +/- 18.01, and 147.45 +/- 17.12, respectively. Additionally, because of the shorter life span in DW strain, two apparent peaks in age-stage specific fecundity were detected. The beetles compensated for their shorter life span by increasing their reproductive activity to sustain the progeny in the population. The intrinsic rates of increase (r) of P. fuscipes from DW, SP, and AJ were 0.0773 +/- 0.0046 d(-1), 0.0788 +/- 0.0051 d(-1), and 0.0873 +/- 0.0054 d(-1), respectively; and the net reproduction rates (R0) were 40.09 +/- 7.39 offspring, 45.29 +/- 8.74 offspring, and 42.34 +/- 8.25 offspring, respectively. The mean generation time of P. fuscipes from AJ was 43.08 +/- 1.07 d, which was significantly higher than that from DW (47.95 +/- 1.36 d) and SP (48.57 +/- 1.43 d). The total immature development time of P. fuscipes in this study was shorter than values reported in previous studies.
Malaria remains a global health problem affecting more than 515 million people all over the world including Malaysia. It is on the rise, even within unknown regions that previous to this were free of malaria. Although malaria eradication programs carried out by vector control programs are still effective, anti-malarial drugs are also used extensively for curtailing this disease. But resistance to the use of anti-malarial drugs is also increasing on a daily basis. With an increased understanding of mechanisms that cause growth, differentiation and development of malarial parasites in rodents and humans, new avenues of therapeutic approaches for controlling the growth, synchronization and development of malarial parasites are essential. Within this context, the recent discoveries related to IP3 interconnected signalling pathways, the release of Ca2+ from intracellular stores of Plasmodium, ubiquitin protease systems as a signalling pathway, and melatonin influencing the growth and differentiation of malarial parasites by its effects on these signalling pathways have opened new therapeutic avenues for arresting the growth and differentiation of malarial parasites. Indeed, the use of melatonin antagonist, luzindole, has inhibited the melatonin's effect on these signalling pathways and thereby has effectively reduced the growth and differentiation of malarial parasites. As Plasmodium has effective sensors which detect the nocturnal plasma melatonin concentrations, suppression of plasma melatonin levels with the use of bright light during the night or by anti-melatonergic drugs and by using anti-kinase drugs will help in eradicating malaria on a global level. A number of patients have been admitted with regards to the control and management of malarial growth. Patents related to the discovery of serpentine receptors on Plasmodium, essential for modulating intra parasitic melatonin levels, procedures for effective delivery of bright light to suppress plasma melatonin levels and thereby arresting the growth and elimination of malarial parasites from the blood of the host are all cited in the paper. The purpose of the paper is to highlight the importance of melatonin acting as a cue for Plasmodium faciparum growth and to discuss the ways of curbing the effects of melatonin on Plasmodium growth and for arresting its life cycle, as a method of eliminating the parasite from the host.
Matched MeSH terms: Life Cycle Stages/drug effects*