Nine adult tree shrews, Tupaia glis, recently imported from West Malaysia were visually examined for ectoparasites while under general anesthesia. Three shrews were infested by the sucking louse, Sathrax durus , and six shrews had louse ova belonging to this species; two shrews had neither lice nor ova. A total of 20 adult female, 10 adult male, and three third instar nymphal lice was collected. Lice were located on the head, flanks, and dorsal body of shrews while ova were recorded mainly from the anterior flanks but also from some adjacent host sites. The tree shrews appeared to tolerate the lice well although louse vector capacity was not assessed. The last date that lice were recorded from shrews was 22 days after colony set-up, and the last date on which seemingly viable ova were recorded was 64 days after set-up showing that the infestations were ultimately lost.
In forensic entomology, larval rearing usually includes the presence of biological contaminants including scuttle flies (Diptera: Phoridae). Scuttle flies are recognized as forensically important insects and have been reported causing nuisance and contamination in laboratory environments. This paper reports for the first time the finding of multiple scuttle fly species affecting colonies of third instar larvae of the Oriental latrine blowfly, Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae), reared indoors at the Forensic Science Simulation Site, Universiti Kebangsaan Malaysia. Adult scuttle flies were discovered inside a rearing container after the emergence of adult C. megacephala., The scuttle fly species are Megaselia scalaris (Loew), M. spiracularis Schmitz and Puliciphora borinquenensis (Wheeler). Notes on the life history and biology of these species are discussed herein.
Two separate observations from recent electrophoretic studies of the systematics and population genetics of laboratory-reared populations which had a long history of colonization in various laboratories, were found to be inconsistent with the present study which used wild-caught populations from East Malaysia. Reanalysis of the two data sets generally indicated a low amount of genetic variation in laboratory colonies. The latter is characterized by higher frequency of monomorphic loci, low average heterozygosity values and, in one extreme case, no variability at two loci. However, natural populations of An. balabacensis and An. leucosphyrus showed more protein variability by the use of polyacrylamide gel electrophoresis. Since laboratory-maintained mosquitoes are genetically and phenotypically different from those in the field, results of laboratory studies on the systematics and population genetics of Anopheles species complexes may be biased.
Matched MeSH terms: Animals, Laboratory/genetics; Animals, Laboratory/growth & development
Animal research plays an important role in the pre-clinical phase of clinical trials. In animal studies, the power analysis approach to sample size calculation is recommended. Whenever it is not possible to assume the standard deviation and the effect size, an alternative to the power analysis approach is the 'resource equation' approach, which sets the acceptable range of the error degrees of freedom (DF) in an analysis of variance (ANOVA). The aim of this article is to guide researchers in calculating the minimum and maximum numbers of animals required in animal research by reformulating the error DF formulas.
Randomly selected samples from different animal colonies from two laboratory animal houses and from the wild-caught monkeys were tested for the presence of anti-rotavirus antibodies to estimate the rates of infection with group A rotavirus. Antibodies to the common group A rotaviral antigen were detected by a competitive enzyme-linked immunosorbent assay (ELISA) using reagents of WHO ELISA rotavirus detection kit. The results of the study showed that white mice, albino rats, and guinea pigs from long-established breeding colonies and resident house rats and house shrews from the animal house had no serological evidence of rotaviral infection. In contrast, one mousedeer from a colony of 19 animals and most of the rabbits from two separate breeding colonies at the same animal house were serologically positive for the infection. Also a significant number of the same species of monkey kept in captivity were found to acquire the infection. Leaf monkeys had no serological evidence of rotaviral infection. The infection rate in wild cynomolgus monkeys did not seem to be influenced by the different ecological environments of their respective habitats. The rate of infection in adults and juveniles was similar.
Nonhuman primates can be used as models for the study of immune-complex-associated diseases. Recognizing that very little is known about the levels of circulating immune complexes (CICs) in normal monkeys, we have used three assays to measure the levels in serum collected from 313 adult and 106 juvenile cynomolgus macaques (Macaca fascicularis). The prevalence was higher than expected. There was a strong statistical association between CIC levels and country of origin. Monkeys from Indonesia were more likely to have elevated CICs than those from Malaya or the Philippines. This relationship was observed with all three assays. Furthermore, juvenile macaques tended to have lower levels than did adults. This study indicates that it may be important to consider genetic factors, the country of origin, or both when selecting cynomolgus macaques for research on immune-complex-associated diseases.
Rabbit strains find immense application in biomedical research with every strain having their discrete advantage in specific research endeavor. Acceptability of rabbit strains as laboratory animals owes to their breeding ease, availability, cost-effectiveness, ethical conveniences, larger size, compared to rats and mice, and responsiveness. With respect to different life phases, the article displays that one human year is equivalent to: (1) in developmental phase, 56.77 days for New Zealand White (NZW) and New Zealand Red (NZR) rabbits, 71.01 days for Dutch belted and Polish rabbits, and 85.28 days for Californian rabbits; (2) in the prepubertal phase, 13.04 days for NZW and Dutch belted, 15.65 days for NZR and Californian, and 10.43 days for Polish rabbits; (3) in the adult phase, 18.25 days for NZW and Californian rabbits, 22.75 days for NZR, and 12 days for Dutch Belted and Polish rabbits; (4) during reproductive senescence, 42.94 days for NZW, NZR and Californian rabbits, 28.62 days for Dutch belted, and 25.05 days for Polish rabbits; (5) in the post-senescence phase, 50.34 days for NZW, 25.17 days for NZR, Dutch Belted and Californian and 31.46 days for Polish rabbits. The laboratory rabbit strains differ in various physiological, developmental and genetic make-ups, which also reflect upon the correlation of their age at different life stages with that of a human. The present article aids selection of laboratory rabbit strain of accurate age as per experimental need, by precisely relating the same with age of human considering different life stages.
Soy sauce, a dark-colored seasoning, is added to enhance the sensory properties of foods. Soy sauce can be consumed as a condiment or added during the preparation of food. There are 3 types of soy sauce: fermented, acid-hydrolyzed vegetable protein (acid- HVP), and mixtures of these. 3-Chloropropane-1,2-diol (3-MCPD) is a heat-produced contaminants formed during the preparation of soy sauce and was found to be a by-product of acid-HVP-produced soy sauce in 1978. 3-MCPD has been reported to be carcinogenic, nephrotoxic, and reproductively toxic in laboratory animal testing and has been registered as a chemosterilant for rodent control. 3-MCPD is classified as a possible carcinogenic compound, and the maximum tolerated limit in food has been established at both national and international levels. The purpose of this review is to provide an overview on the detection of 3-MCPD in soy sauce, its toxic effects, and the potential methods to reduce its concentration, especially during the production of acid-HVP soy sauce. The methods of quantification are also critically reviewed with a focus on efficiency, suitability, and challenges encountered in analysis.
Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) in which activated immune cells attack the CNS and cause inflammation and demyelination. While the etiology of MS is still largely unknown, the interaction between hormones and the immune system plays a role in disease progression, but the mechanisms by which this occurs are incompletely understood. Several in vitro and in vivo experimental, but also clinical studies, have addressed the possible role of the endocrine system in susceptibility and severity of autoimmune diseases. Although there are several demyelinating models, experimental autoimmune encephalomyelitis (EAE) is the oldest and most commonly used model for MS in laboratory animals which enables researchers to translate their findings from EAE into human. Evidences imply that there is great heterogeneity in the susceptibility to the induction, the method of induction, and the response to various immunological or pharmacological interventions, which led to conflicting results on the role of specific hormones in the EAE model. In this review, we address the role of endocrine system in EAE model to provide a comprehensive view and a better understanding of the interactions between the endocrine and the immune systems in various models of EAE, to open up a ground for further detailed studies in this field by considering and comparing the results and models used in previous studies.
Objective: to review the field of epigenetics, and present basic and recent material that may be of interest to clinical psychiatrists. We include basic molecular mechanism, a consideration of findings related to mental disorders, evidence of sustained effects, and the evidence for and implications of transgenerational epigenetic modifications. Method: we examined all the available papers for the last five years identified by PubMed using the words ‘epigenetics’ and ‘epigenetics psychiatry’, and the available leading specialized textbooks. Results: we report on molecular mechanisms including DNA and histone modifications, and non-coding RNAs. While some modifications are short-lived, others are life-long. Depression, suicide, schizophrenia, PTSD, borderline personality disorder and drug addiction are among the conditions for which epigenetic involvement has been proposed. Transgenerational epigenetics enables the environmental experience of one generation to be non-genetically inherited by subsequent generations. This has been molecularly demonstrated in laboratory animals and epidemically suggested in humans. Conclusions: epigenetics provides a new way of understanding human behavior and points to potential therapies for mental disorders. Should it transpire that transgenerational epigenetic modifications apply with force in humans as they do to laboratory animals, this will emphasize the need for cultural shift, safe societies with ample opportunities.
One of the compounds present in Pluchea indica extracts is antioxidant which plays an important role in inhibiting free radicals and thus protects humans against infections and degenerative diseases, such as cancer, arthritis, and ageing process. The main objective of this study was to investigate and determine the total phenolic compounds of Pluchea indica in different concentrations of ethanolic extracts. This species was chosen because of its high phytonutrient compounds with potential medicinal properties. There was a significant difference (P ≤ 0.05) in the total phenolic among the different parts of the tested plant. 50% of the ethanolic extract produced the highest total phenolic compounds (1775.00±86.00 to 658.95±5.00 µmol/g), followed by water extract (759.79±1.53 µmol/g) and 100% ethanol extract (352.72±22.30 to 249.29±5.37 µmol/g), respectively. In terms of the plant parts, the leaves contained the highest phenolic compounds (1775.00±86.00 µmol/g in 50% ethanol extract, 759.79±1.53 µmol/g in 100% aqueous extract and 352.72±22.30 µmol/g in 100% ethanol extract), followed by the stems (990.22±24.00 µmol/g in 50% ethanol extract, 990.22±24.59 µmol/g in 100% aqueous extract and 293.48±0.00 µmol/g in 100% ethanol extract). Meanwhile, lower total phenolic compounds were detected in the flowers (727.71±11.00 µmol/g in 50% ethanol extract, 603.81±8.46 µmol/g in 100% aqueous extract and 249.29±5.37 µmol/g in 100% ethanol extract) and roots (658.95±5.00 µmol/g in 50% ethanol extract, 450.00±10.76 µmol/g in 100% aqueous extract and 272.28±0.53 µmol/g in 100% ethanol extract). Based on these findings, Pluchea indica has potential medicinal properties that can be further developed to produce neutraceutical products, diet supplements or cosmetic products. However, further research should first be conducted on the effects of these compounds on laboratory animals.
In the present study, a 50% ethanolic extract of Orthosiphon stamineus was tested for its α-glucosidase inhibitory activity. In vivo assays of the extract (containing 1.02%, 3.76%, and 3.03% of 3'hydroxy-5,6,7,4'-tetramethoxyflavone, sinensetin, and eupatorin, resp.) showed that it possessed an inhibitory activity against α-glucosidase in normal rats loaded with starch and sucrose. The results showed that 1000 mg/kg of the 50% ethanolic extract of O. stamineus significantly (P < 0.05) decreased the plasma glucose levels of the experimental animals in a manner resembling the effect of acarbose. In streptozotocin-induced diabetic rats, only the group treated with 1000 mg/kg of the extract showed significantly (P < 0.05) lower plasma glucose levels after starch loading. Hence, α-glucosidase inhibition might be one of the mechanisms by which O. stamineus extract exerts its antidiabetic effect. Furthermore, our findings indicated that the 50% ethanolic extract of O. stamineus can be considered as a potential agent for the management of diabetes mellitus.
The present study was designed to investigate the total carbohydrate, total protein, and glycogen levels in the liver and to measure functional liver markers such as aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in streptozotocin-(STZ-) induced diabetic rats after treatment with methanolic extract of Rhinacanthus nasutus (R. nasutus). The methanolic extract of R. nasutus was orally administered at 200 mg/kg/day while glibenclamide was administered at 50 mg/kg/day. All animals were treated for 30 days before being sacrificed. The amounts of carbohydrate, glycogen, proteins, and liver markers (AST and ALT) were measured in the liver tissue of the experimental animals. The levels of carbohydrate, glycogen, and proteins were significantly reduced in the diabetic rats but were augmented considerably after 30 days of R. nasutus treatment. The elevated AST and ALT levels in diabetic rats showed a significant decline after treatment with R. nasutus for 30 days. These results show that the administration of R. nasutus ameliorates the altered levels of carbohydrate, glycogen, proteins, and AST and ALT observed in diabetic rats and indicate that R. nasutus restores overall metabolism and liver function in experimental diabetic rats. In conclusion, the outcomes of the present study support the traditional belief that R. nasutus could ameliorate the diabetic state.
Human pluripotent stem cells (hPSCs) derived from either blastocyst stage embryos (hESCs) or reprogrammed somatic cells (iPSCs) can provide an abundant source of human neuronal lineages that were previously sourced from human cadavers, abortuses, and discarded surgical waste. In addition to the well-known potential therapeutic application of these cells in regenerative medicine, these are also various promising nontherapeutic applications in toxicological and pharmacological screening of neuroactive compounds, as well as for in vitro modeling of neurodegenerative and neurodevelopmental disorders. Compared to alternative research models based on laboratory animals and immortalized cancer-derived human neural cell lines, neuronal cells differentiated from hPSCs possess the advantages of species specificity together with genetic and physiological normality, which could more closely recapitulate in vivo conditions within the human central nervous system. This review critically examines the various potential nontherapeutic applications of hPSC-derived neuronal lineages and gives a brief overview of differentiation protocols utilized to generate these cells from hESCs and iPSCs.
An epizootic of measles occurred in a group of 31 silvered leaf-monkeys (Presbytis cristatus) that had been in captivity for 4-12 months. Twenty-four of the monkeys exhibited a maculopapular rash that persisted for 6-9 days. A serous to mucopurulent nasal discharge and conjunctivitis were seen in some animals. Eight monkeys died during the epizootic; however, their deaths could not be directly attributed to measles. Serum samples from the surviving monkeys collected 1-2 months prior to, and 5 weeks after, the epizootic were examined by the complement-fixation and hemagglutination-inhibition tests for antibodies to measles virus. The preepizootic complement-fixation titers were all less than 1:4 and hemagglutination-inhibition titers, less than 1:10. The postepizootic complement-fixation titers in 21 of 23 surviving monkeys ranged from 1:8 to 1:128, and hemagglutination-inhibition titers in 22 of 23 monkeys ranged from 1:40 to 1:80 or greater.