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Fulltext Life-history constraints, short adult life span and reproductive strategies in coral reef gobies of the genus Trimma

Goldsworthy NC, Srinivasan M, Smallhorn-West P, Cheah LC, Munday PL, Jones GP

J Fish Biol, 2022 Oct;101(4):996-1007.
PMID: 35818109 DOI: 10.1111/jfb.15161

Body size influences many life-history traits, with small-bodied animals tending to have short life spans, high mortality and greater reproductive effort early in life. In this study, the authors investigated the life-history traits and reproductive strategies of three small-bodied coral reef gobies of the genus Trimma: Trimma benjamini, Trimma capostriatum and Trimma yanoi. The authors found all Trimma species studied attained a small body size of <25 mm, had a short life span of <140 days and experienced high estimated daily mortality of 3.0%-6.7%. Furthermore, the pelagic larval phase accounted for 25.3%-28.5% of the maximum life span, and maturation occurred between 74.1 and 82.1 days at 15.2-15.8 mm, leaving only 35%-43% of the total life span as a reproductively viable adult. All mature individuals had gonad structures consistent with bidirectional sex change, with bisexual gonads including both ovarian and testicular portions separated by a thin wall of connective tissue. In the female and male phases, only ovaries or testes were mature, whereas gonadal tissue of the non-active sex remained. One T. benjamini individual and one T. yanoi individual had ovarian and testicular tissue active simultaneously. The results of this study highlight the life-history challenges small CRFs face on their path to reproduction and reproductive strategies that could be beneficial in fishes with high and unpredictable mortality and short reproductive life spans.

Matched MeSH terms: Longevity
Fulltext The Importance of the Expendable: Toxin-Antitoxin Genes in Plasmids and Chromosomes

Díaz-Orejas R, Espinosa M, Yeo CC

Front Microbiol, 2017;8:1479.
PMID: 28824602 DOI: 10.3389/fmicb.2017.01479

Toxin-antitoxin (TA) genes were first reported in plasmids and were considered expendable genetic cassettes involved in the stable maintenance of the plasmid replicon by interfering with growth and/or viability of bacteria in which the plasmid was lost. TAs were later found in bacterial chromosomes and also in integrated mobile genetic elements; they were proposed to be involved in the bacterial response to stressful situations. At present, 100s of TAs have been identified and classified in up to six families (I to VI), with those belonging to the type II (constituted by two protein components) being the most studied. Based on well-characterized examples of several type II TAs, we discuss in this review that irrespective of their locations in plasmids or chromosomes, TAs functionally overlap as indicated by: (i) in both locations they can mediate the maintenance of genetic elements to which they are physical linked, and (ii) they can induce persistence or virulence in response to stress situations. Examples of functional confluences in homologous TA systems with different locations are also given. We also consider whether the physiological role of TAs is due to their genetic organization as operons or to their inherent properties, like the short lifespan of the antitoxin component.

Matched MeSH terms: Longevity
Fulltext A Multitasking Electrical Impedance Tomography System Using Titanium Alloy Electrode

Salama A, Malekmohammadi A, Mohanna S, Rajkumar R

Int J Biomed Imaging, 2017;2017:3589324.
PMID: 29225613 DOI: 10.1155/2017/3589324

This paper presents a multitasking electrical impedance tomography (EIT) system designed to improve the flexibility and durability of an existing EIT system. The ability of the present EIT system to detect, locate, and reshape objects was evaluated by four different experiments. The results of the study show that the system can detect and locate an object with a diameter as small as 1.5 mm in a testing tank with a diameter of 134 mm. Moreover, the results demonstrate the ability of the current system to reconstruct an image of several dielectric object shapes. Based on the results of the experiments, the programmable EIT system can adapt the EIT system for different applications without the need to implement a new EIT system, which may help to save time and cost. The setup for all the experiments consisted of a testing tank with an attached 16-electrode array made of titanium alloy grade 2. The titanium alloy electrode was used to enhance EIT system's durability and lifespan.

Matched MeSH terms: Longevity
Fulltext Semi-direct composite restorations- a clinical report

Berhanuddin Muhamad Asyraf, Tong, Wah Lim

Malaysian Dental Journal, 2016;2016(2):0-0.
MyJurnal

In nowadays world, aesthetic dentistry has becoming a trend with the improvement of dental technology and materials. Composite resin becomes the material of choice as it offers good aesthetics, longevity and allow for minimally intervention approach. There are various ways of composite restorative techniques recommended to make out the best restorative outcome. Direct restorative technique promise acceptable cost, appointment time and color matching but it is a challenge for the clinician especially for extensive cavities. Indirect technique is good for extended cavity and providing less operator error, however, it requires multiple appointments, higher cost and laboratory involvement. Computer-aided design/ computer-aided manufacturing (CAD/CAM) technology might reduce the number of appointments, however, it will cause more financial burden to the patient and the clinician. Therefore, semi-direct technique was introduced, it combines the benefits of direct and indirect technique and this technique can be done without the use of any advanced technology and give out a good treatment outcome.

Matched MeSH terms: Longevity
Methodology approaches and challenges in population-based longitudinal study of a neuroprotective model for healthy longevity

Lau H, Shahar S, Hussin N, Kamarudin MZ, Hamid TA, Mukari SZ, et al.

Geriatr Gerontol Int, 2019 Mar;19(3):233-239.
PMID: 30618211 DOI: 10.1111/ggi.13598

AIM: The 36-month Long-Term Research Grant Scheme project: Towards Usual Aging - Neuroprotective Model for Healthy Longevity among Malaysian Elderly was designed to address multidimensional aspects including psychosocial, biophysical health, nutrition and dietary pattern, and auditory and visual function to highlight the magnitude of these associations in a single study.
METHODS: A total of 2322 respondents aged ≥60 years were recruited at baseline using the multistage sampling method, followed up at 18 months and 36 months.
RESULTS: Response rates at baseline, 18 months and 36 months were 87.8%, 77.3% and 67.1%, respectively. At baseline, the prevalence of successful aging, usual aging and mild cognitive impairment was 11%, 73% and 16%, respectively. The prevalence of single and multimorbidity at baseline were 25.9% and 50.3%, respectively. The incidence rates of mild cognitive impairment at 18 months and 36 months were 6.5 and 5.6 per 100 person-years. The incidence rates of multimorbidity at 18 months and 36 months were 23.7 and 21.5 per 100 person-years, respectively.
CONCLUSIONS: The Long-Term Research Grant Scheme project: Towards Usual Aging study provides an opportunity to investigate the interactions between wide ranges of aspects of the older population in a nationally representative sample of the older population. Geriatr Gerontol Int 2019; 19: 233-239.

Matched MeSH terms: Longevity
Fulltext Optimization of Micro and Nano Palm Oil Fuel Ash to Determine the Carbonation Resistance of the Concrete in Accelerated Condition

Tang WL, Lee HS, Vimonsatit V, Htut T, Singh JK, Wan Hassan WNF, et al.

Materials (Basel), 2019 Jan 03;12(1).
PMID: 30609786 DOI: 10.3390/ma12010130

The carbonation rate of reinforced concrete is influenced by three parameters, namely temperature, relative humidity, and concentration of carbon dioxide (CO₂) in the surroundings. As knowledge of the service lifespan of reinforced concrete is crucial in terms of corrosion, the carbonation process is important to study, and high-performance durable reinforced concretes can be produced to prolong the effects of corrosion. To examine carbonation resistance, accelerated carbonation testing was conducted in accordance with the standards of BS 1881-210:2013. In this study, 10⁻30% of micro palm oil fuel ash (mPOFA) and 0.5⁻1.5% of nano-POFA (nPOFA) were incorporated into concrete mixtures to determine the optimum amount for achieving the highest carbonation resistance after 28 days water curing and accelerated CO₂ conditions up to 70 days of exposure. The effect of carbonation on concrete specimens with the inclusion of mPOFA and nPOFA was investigated. The carbonation depth was identified by phenolphthalein solution. The highest carbonation resistance of concrete was found after the inclusion of 10% mPOFA and 0.5% nPOFA, while the lowest carbonation resistance was found after the inclusion of 30% mPOFA and 1.5% nPOFA.

Matched MeSH terms: Longevity
Fecundity, fertility and survival of red palm weevil (Rhynchophorus ferrugineus) larvae reared on sago palm

Wahizatul Afzan Azmi, Yong Kah Wai, Aisyah Abu Bakar

Sains Malaysiana, 2015;44:1371-1375.

AISYAH ABU BAKARRed palm weevil (RPW), Rhynchophorus ferrugineus has been reported as a serious pest of coconut, sago palm and date palm in many parts of the world. In Malaysia, RPW is a lethal pest of coconut in Terengganu and sago palm in Sarawak. However, very limited information about the reproductive performance of RPW is available, specifically in Malaysia. In the present study, the reproductive performance of RPW reared on sago palm (Metroxylon sagu) were studied using nine pairs of virgin RPW under laboratory conditions. The number of eggs laid and eggs viability were recorded daily until females could not produce eggs. The total number of eggs laid were 3081 and the average number of eggs deposited by a female was 342.3+0.97 eggs (ranged from 270 to 396). The percentage of hatchability was 52.4% and out of the total 1614 hatched eggs, only 118 individuals (7.3%) were survived until late instar. However, no significant differences in fecundity, hatchability and total survived larvae in different RPW pairs were observed. Females longevity was found to be strongly influenced by the number of eggs laid; the higher number of eggs laid, the shorter is the life span of the female. This study is important to understand the biological aspects of RPW, as a first step to develop effective control strategy of the pest.

Matched MeSH terms: Longevity
Supported liquid membrane extraction of nickel using stable composite SPEEK/PVDF support impregnated with a sustainable liquid membrane

Sulaiman RNR, Jusoh N, Othman N, Noah NFM, Rosly MB, Rahman HA

J Hazard Mater, 2019 12 15;380:120895.
PMID: 31351388 DOI: 10.1016/j.jhazmat.2019.120895

A sustainable and stable supported liquid membrane (SLM) extraction of nickel was developed via impregnation of sustainable liquid membrane in the composite membrane support consisting of polyvinylidene fluoride (PVDF) and sulfonated poly (ether ether ketone) (SPEEK). Bis-2-ethylhexyl phosphate (D2EHPA), 1-octanol, refined palm oil and sulfuric acid were employed as extractant, synergist extractant, diluent and strippant, respectively. Variables studied including effect of refined palm oil compositions as well as the configurations and thicknesses of SPEEK. Lifespan of SLM was evaluated by recycling the composite membrane support. Results revealed that upon using 100% refined palm oil, about 100% of nickel was extracted and recovered in 10 and 14 h, respectively. Composite SPEEK/PVDF stabilized SLM by reducing liquid membrane loss from 47 to 23% upon applying SPEEK at the feed side of PVDF support. High permeability and flux values were obtained at 9.26 x 10-4 cms-1 and 6.48 x 10-7 molcm-2s-1 when increasing SPEEK thickness from 0.025 to 0.055 mm, respectively. The lifespan of SLM was extended up to ninth cycles with low weight loss percentage of the impregnated composite membrane (8%). In conclusion, the SPEEK/PVDF impregnated with refined palm oil has improved the stability of SLM extraction of nickel ions from industrial wastewater.

Matched MeSH terms: Longevity
Linking size-dependent growth and mortality with architectural traits across 145 co-occurring tropical tree species

Iida Y, Poorter L, Sterck F, Kassim AR, Potts MD, Kubo T, et al.

Ecology, 2014 Feb;95(2):353-63.
PMID: 24669729

Tree architecture, growth, and mortality change with increasing tree size and associated light conditions. To date, few studies have quantified how size-dependent changes in growth and mortality rates co-vary with architectural traits, and how such size-dependent changes differ across species and possible light capture strategies. We applied a hierarchical Bayesian model to quantify size-dependent changes in demographic rates and correlated demographic rates and architectural traits for 145 co-occurring Malaysian rain-forest tree species covering a wide range of tree sizes. Demographic rates were estimated using relative growth rate in stem diameter (RGR) and mortality rate as a function of stem diameter. Architectural traits examined were adult stature measured as the 95-percentile of the maximum stem diameter (upper diameter), wood density, and three tree architectural variables: tree height, foliage height, and crown width. Correlations between demographic rates and architectural traits were examined for stem diameters ranging from 1 to 47 cm. As a result, RGR and mortality varied significantly with increasing stem diameter across species. At smaller stem diameters, RGR was higher for tall trees with wide crowns, large upper diameter, and low wood density. Increased mortality was associated with low wood density at small diameters, and associated with small upper diameter and wide crowns over a wide range of stem diameters. Positive correlations between RGR and mortality were found over the whole range of stem diameters, but they were significant only at small stem diameters. Associations between architectural traits and demographic rates were strongest at small stem diameters. In the dark understory of tropical rain forests, the limiting amount of light is likely to make the interspecific difference in the effects of functional traits on demography more clear. Demographic performance is therefore tightly linked with architectural traits such as adult stature, wood density, and capacity for horizontal crown expansion. The enhancement of a demographic trade-off due to interspecific variation in functional traits in the understory helps to explain species coexistence in diverse rain forests.

Matched MeSH terms: Longevity
Fulltext Improving Performance of Electrospun Nylon 6,6 Nanofiber Membrane for Produced Water Filtration via Solvent Vapor Treatment

Abd Halim NS, Wirzal MDH, Bilad MR, Md Nordin NAH, Adi Putra Z, Sambudi NS, et al.

Polymers (Basel), 2019 Dec 17;11(12).
PMID: 31861059 DOI: 10.3390/polym11122117

Electrospun nanofiber membrane (NFM) has a high potential to be applied as a filter for produced water treatment due to its highly porous structure and great permeability. However, it faces fouling issues and has low mechanical properties, which reduces the performance and lifespan of the membrane. NFM has a low integrity and the fine mat easily detaches from the sheet. In this study, nylon 6,6 was selected as the polymer since it offers great hydrophilicity. In order to increase mechanical strength and separation performance of NFM, solvent vapor treatment was implemented where the vapor induces the fusion of fibers. The fabricated nylon 6,6 NFMs were treated with different exposure times of formic acid vapor. Results show that solvent vapor treatment helps to induce the fusion of overlapping fibers. The optimum exposure time for solvent vapor is 5 h to offer full retention of dispersed oil (100% of oil rejection), has 62% higher in tensile strength (1950 MPa) compared to untreated nylon 6,6 NFM (738 MPa), and has the final permeability closest to the untreated nylon 6,6 NFM (733 L/m2.h.bar). It also took more time to get fouled (220 min) compared to untreated NFM (160 min).

Matched MeSH terms: Longevity
Fulltext Wolbachia's Deleterious Impact on Aedes aegypti Egg Development: The Potential Role of Nutritional Parasitism

Allman MJ, Fraser JE, Ritchie SA, Joubert DA, Simmons CP, Flores HA

Insects, 2020 Oct 27;11(11).
PMID: 33120915 DOI: 10.3390/insects11110735

The artificial introduction of the endosymbiotic bacterium, Wolbachia pipientis, into Aedes (Ae.) aegypti mosquitoes reduces the ability of mosquitoes to transmit human pathogenic viruses and is now being developed as a biocontrol tool. Successful introgression of Wolbachia-carrying Ae. aegypti into native mosquito populations at field sites in Australia, Indonesia and Malaysia has been associated with reduced disease prevalence in the treated community. In separate field programs, Wolbachia is also being used as a mosquito population suppression tool, where the release of male only Wolbachia-infected Ae. aegypti prevents the native mosquito population from producing viable eggs, subsequently suppressing the wild population. While these technologies show great promise, they require mass rearing of mosquitoes for implementation on a scale that has not previously been done. In addition, Wolbachia induces some negative fitness effects on Ae. aegypti. While these fitness effects differ depending on the Wolbachia strain present, one of the most consistent and significant impacts is the shortened longevity and viability of eggs. This review examines the body of evidence behind Wolbachia's negative effect on eggs, assesses nutritional parasitism as a key cause and considers how these impacts could be overcome to achieve efficient large-scale rearing of these mosquitoes.

Matched MeSH terms: Longevity
Genomic Instability and Cellular Senescence: Lessons From the Budding Yeast

Lee JW, Ong EBB

Front Cell Dev Biol, 2020;8:619126.
PMID: 33511130 DOI: 10.3389/fcell.2020.619126

Aging is a complex biological process that occurs in all living organisms. Aging is initiated by the gradual accumulation of biomolecular damage in cells leading to the loss of cellular function and ultimately death. Cellular senescence is one such pathway that leads to aging. The accumulation of nucleic acid damage and genetic alterations that activate permanent cell-cycle arrest triggers the process of senescence. Cellular senescence can result from telomere erosion and ribosomal DNA instability. In this review, we summarize the molecular mechanisms of telomere length homeostasis and ribosomal DNA stability, and describe how these mechanisms are linked to cellular senescence and longevity through lessons learned from budding yeast.

Matched MeSH terms: Longevity
Fulltext Barriers to health promotion for indigenous communities: lessons for Malaysia

Aniza, I, Norhayati, M

Malaysian Journal of Public Health Medicine, 2016;16(1):6-14.
MyJurnal

Globally, the health of the indigenous people is lagging behind as compared to the mainstream population in countries in which they live. Despite improved overall prosperity and population longevity, social and health inequalities seem to persist in this underprivileged community. Failure in delivering effective health promotion toward the indigenous community is determined by a range of factors. This includes the absence of culturally sensitive awareness among the healthcare workers, ineffective communication of the healthcare providers, poor access to health service, lack of culturally specific health promotional materials, lack of involvement by indigenous healthcare workers, lack of community based programs and inefficiency of indigenous health data collection. Effective interventions for indigenous health require a trans-disciplinary and holistic approach that incorporates indigenous health beliefs and engages with the social and cultural drivers of health.Such culturally congruent health promotion strategies are hoped to narrow down the existing wide gap of health outcomes that contribute to inequalities between indigenous communities and the mainstream population.

Matched MeSH terms: Longevity
Fulltext The effect of mating on the eggs’ fertility and fecundity of Helopeltis antonii (Heteroptera: Miridae)

Siswanto, Rita Muhamad, Dzolkhifli Omar, Elna Karmawati

Trop Life Sci Res, 2009;20(1):-.
MyJurnal

Helopeltis antonii is the major pest affecting cashew plants in Indonesia and causes potential damage to the plant. The development of the population was influenced by the fecundity and fertility of their eggs. The effect of mating on the eggs’ fecundity and the fertility of H. antonii was studied. Laboratory studies at Wonogiri Estate Service in Ngadirojo District, Wonogiri, Indonesia investigated the sexual maturity, the influence of female to male sex ratio on the females’ fecundity and longevity, and the influence of mating frequency to fecundity and the eggs hatchability of H. antonii. The study reveals that H. antonii females and males are ready to mate when they are two days old. The number of eggs laid and the longevity of the females’ lives were not significantly affected by the sex ratio; however, female to male sex ratios of 2:1 and 1:2 tended to produce a greater number of eggs. The fecundity of the female was not significantly influenced by the number of times the female mated. Unmated females laid fewer eggs than females paired with a mature male. The study shows that females need to mate to produce fertile eggs.

Matched MeSH terms: Longevity
Fulltext Introducing a technique in sustaining adult worker bees of Heterotrigona itama (Cockerell, 1918) in laboratory to facilitate future health research on Kelulut honey

Syazana Jumaan, Jahangir Kamaldin, Rosliza Jajuli, Izfa Riza Hazmi

Malaysian Journal of Medicine and Health Sciences, 2020;16(102):22-30.
MyJurnal

Introduction: The study is introducing a laboratory technique to sustain the longevity of Heterotrigona itama sting- less bees collected from the farm in order to facilitate future health research on Kelulut honey. Methods: The worker bees were held in laboratory at 26 ± 2 oC, 57 ± 8 % relative humidity (RH) and 12:12 hours (light:dark period) in a cup covered with meshed cloth and installed with an inverted-wick system consists of a drinking straw with the bottom end loosely plugged with cotton wool. The artificial diet was pipetted into the straw to wet the cotton wool. The bees were divided into five diet groups, namely a) unfed - control, b) distilled water, c) purified tap water, d) non-carbonated isotonic drink or e) 5% honey solution. Feeding activity and survival of worker bees were observed daily. Results: The worker bees are seen to frequent and lick the cotton wool wetted with artificial diets. Comparison between the artificial diets, Kaplan-Meier statistical analysis showed that the 5% honey solution and non-carbonated isotonic drink have significantly (P < 0.05) extended the longevity of the worker bees with 50% survival probability at least 8 days. When the similar holding and feeding technique used for the bees from commercial farms, the 50% survival probability was extended to 14 days. Conclusion: The inverted-wick system with the use of 5% honey solu- tion or isotonic drink as the artificial diet is capable to hold the H. itama worker bees at least for a week with survival above 50% for laboratory experiments.

Matched MeSH terms: Longevity
Fulltext Population analysis of Aedes albopictus (Skuse) (Diptera:Culicidae) under uncontrolled laboratory conditions

Nur Aida H, Abu Hassan A, Nurita AT, Che Salmah MR, Norasmah B

Trop Biomed, 2008 Aug;25(2):117-25.
PMID: 18948882

A semi laboratory experiment using 3 cohorts of Aedes albopictus adults was performed to obtain age-specific mortality and fecundity information and to derive statistical estimates of some population growth parameters. Life expectancy was calculated for both males and females. The following population parameters were estimated: intrinsic rate of increase (rm= 0.21), net reproductive (replacement) rate (Ro= 68.70), age at mean cohort reproduction (To=10.55 days), birth rate (B=0.23), death rate (D=0.02) and generation time (G=20.14 days). The high rm/B (0.91) and B/D (11.50) ratios indicated the high colonizing ability of Ae. albopictus in nature.

Matched MeSH terms: Longevity
Artemisia argyi extract exerts antioxidant properties and extends the lifespan of Drosophila melanogaster

Yang Y, Cao Y, Zhang J, Fan L, Huang Y, Tan TC, et al.

J Sci Food Agric, 2024 May;104(7):3926-3935.
PMID: 38252625 DOI: 10.1002/jsfa.13273

BACKGROUND: Chinese mugwort (Artemisia argyi) possesses extensive pharmacological activities associated with anti-tumour, antioxidative and anti-inflammatory effects. The present study aimed to investigate the antioxidant and anti-ageing effects of A. argyi extract (AAE) on the fruit fly (Drosophila melanogaster) ageing model by detecting antioxidant enzyme activities and the mRNA level of antioxidant genes.
RESULTS: AAE could significantly lengthen the mean lifespan, 50% survival days, and maximum lifespan of D. melanogaster, especially when the amount of AAE added reached 6.68 mg mL-1, the mean lifespan of both female and male flies increased by 23.74% and 22.30%, respectively, indicating the effective life extension effect of AAE. At the same time, AAE could improve the climbing ability and tolerance to hydrogen peroxide in D. melanogaster. In addition, the addition of AAE effectively increased the activities of copper-zinc-containing superoxide dismutase, manganese-containing superoxide dismutase and catalase in D. melanogaster and reduced the contents of malondialdehyde. Moreover, when reared with diets containing AAE, the expression of antioxidant-related genes SOD1, SOD2 and CAT was up-regulated in D. melanogaster and down-regulated for MTH genes.
CONCLUSION: The study indicates that AAE effectively enhances the antioxidant capacity of D. melanogaster and has potential applications as an antioxidant and anti-ageing agent in the nutraceutical industry. © 2024 Society of Chemical Industry.

Matched MeSH terms: Longevity
A Laboratory Maintenance Regime for a Fungus-Growing Termite Macrotermes gilvus (Blattodea: Termitidae)

Lee CC, Lee CY

J Econ Entomol, 2015 Jun;108(3):1243-50.
PMID: 26470252 DOI: 10.1093/jee/tov112

The optimum maintenance conditions of the fungus-growing termite, Macrotermes gilvus (Hagen) (Blattodea: Termitidae), in the laboratory were studied. Termites were kept on a matrix of moist sand and with fungus comb as food. The survival of groups of termites was measured when maintained at different population densities by changing group size and container volume. Larger groups (≥0.6 g) were more vigorous and had significant higher survival rates than smaller groups (≤0.3 g). The population density for optimal survival of M. gilvus is 0.0025 g per container volume (ml) or 0.0169 g per matrix volume (cm(3)), i.e., 1.2 g of termites kept in a 480-ml container filled with 71 cm3 of sand. In termite groups of smaller size (i.e., 0.3 g) or groups maintained in smaller container (i.e., 100 ml) the fungus comb was overgrown with Xylaria spp., and subsequently all termites died within the study period. The insufficient number of workers for regulating the growth of unwanted fungi other than Termitomyces spp. in the fungus comb is the most likely reason. Unlike some other mound-building termite species, M. gilvus showed satisfactory survival when maintained in non-nutritious matrix (i.e., sand). There was no significant difference in the survival rate between different colonies of M. gilvus (n=5), with survival in the range of 78.5-84.4% after 4 wk. Advances in the maintenance of Macrotermes will enable researchers to study with more biological relevance many aspects of the biology, behavior, and management of this species.

Matched MeSH terms: Longevity
Effects of simulated microgravity on gene expression and biological phenotypes of a single generation Caenorhabditis elegans cultured on 2 different media

Tee LF, Neoh HM, Then SM, Murad NA, Asillam MF, Hashim MH, et al.

Life Sci Space Res (Amst), 2017 Nov;15:11-17.
PMID: 29198309 DOI: 10.1016/j.lssr.2017.06.002

Studies of multigenerational Caenorhabditis elegans exposed to long-term spaceflight have revealed expression changes of genes involved in longevity, DNA repair, and locomotion. However, results from spaceflight experiments are difficult to reproduce as space missions are costly and opportunities are rather limited for researchers. In addition, multigenerational cultures of C. elegans used in previous studies contribute to mixture of gene expression profiles from both larvae and adult worms, which were recently reported to be different. Usage of different culture media during microgravity simulation experiments might also give rise to differences in the gene expression and biological phenotypes of the worms. In this study, we investigated the effects of simulated microgravity on the gene expression and biological phenotype profiles of a single generation of C. elegans worms cultured on 2 different culture media. A desktop Random Positioning Machine (RPM) was used to simulate microgravity on the worms for approximately 52 to 54 h. Gene expression profile was analysed using the Affymetrix GeneChip® C. elegans 1.0 ST Array. Only one gene (R01H2.2) was found to be downregulated in nematode growth medium (NGM)-cultured worms exposed to simulated microgravity. On the other hand, eight genes were differentially expressed for C. elegans Maintenance Medium (CeMM)-cultured worms in microgravity; six were upregulated, while two were downregulated. Five of the upregulated genes (C07E3.15, C34H3.21, C32D5.16, F35H8.9 and C34F11.17) encode non-coding RNAs. In terms of biological phenotype, we observed that microgravity-simulated worms experienced minimal changes in terms of lifespan, locomotion and reproductive capabilities in comparison with the ground controls. Taking it all together, simulated microgravity on a single generation of C. elegans did not confer major changes to their gene expression and biological phenotype. Nevertheless, exposure of the worms to microgravity lead to higher expression of non-coding RNA genes, which may play an epigenetic role in the worms during longer terms of microgravity exposure.

Matched MeSH terms: Longevity/drug effects
Fulltext IL35 modulation altered survival, cytokine environment and histopathological consequences during malaria infection in mice

Bello RO, Abdullah MA, Abd Majid R, Chin VK, Abd Rachman Isnadi MF, Ibraheem ZO, et al.

Malar J, 2019 Dec 19;18(1):434.
PMID: 31856836 DOI: 10.1186/s12936-019-3070-x

BACKGROUND: The immune modulating potential of IL-35 in multiple human disorders has been reported. Consequent upon the recognition of inflammatory cytokine activation and its preponderance for mediating pathology during malaria infection, the study aimed to characterize the expression and functional contribution(s) of IL-35 in Plasmodium berghei (strain ANKA) infected mice.
METHODS: Plasmodium berghei infection in male ICR mice was used as the rodent model of choice. The time course of IL-35 expression in the systemic circulation and tissues of P. berghei infected mice as well as their healthy control counterparts was assessed by enzyme linked immunosorbent assay and immunohistochemistry respectively. The effect of modulating IL-35 by recombinant IL-35 protein or neutralizing anti-Epstein-Barr virus-induced gene 3 antibody on the cytokine environment during P. berghei infection was assessed by flow cytometry. Furthermore, the influence of modulating IL-35 on histopathological hallmarks of malaria and disease progression was evaluated.
RESULTS: Interleukin-35 was significantly up regulated in serum and tissues of P. berghei infected mice and correlated with parasitaemia. Neutralization of IL-35 significantly enhanced the release of IFN-γ, decreased the expression of IL-6 and decreased parasitaemia patency. Neutralization of IL-35 was also associated with a tendency towards increased survival as well as the absence of pathological features associated with malaria infection unlike recombinant IL-35 protein administration which sustained a normal course of infection and unfavourable malaria associated histological outcomes in P. berghei infected mice.
CONCLUSION: These results indicate the involvement of IL-35 in P. berghei induced malaria infection. IL-35 neutralization strategies may represent viable therapeutic modalities beneficial for the resolution of malaria infection.

Matched MeSH terms: Longevity/drug effects

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