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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
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
A review of radiation hazards with special reference to diagnostic radiology

Ang AH

Med J Malaysia, 1973 Dec;28(2):75-9.
PMID: 4276302
Matched MeSH terms: Longevity
Fulltext A systematic review and meta-analysis of the effects of temperature on the development and survival of the Aedes mosquito

Nik Abdull Halim NMH, Che Dom N, Dapari R, Salim H, Precha N

Front Public Health, 2022;10:1074028.
PMID: 36600940 DOI: 10.3389/fpubh.2022.1074028

INTRODUCTION: The Aedes mosquito species, which are the vectors for the transmission of the dengue virus (DENV) to humans, are becoming increasingly susceptible to the formidable effects of influential factors, especially temperature. However, there are still very few studies that have systematically reviewed the existing literature. Hence, in the present study, a systematic literature review and meta-analysis was conducted into the effects of temperature on dengue vectors.
METHOD: Several research methodologies were incorporated into the current study, and a review was carried out using PRISMA as a guide. The publications for this study were chosen from two prominent databases, Scopus and Web of Science. All of the studies were assessed, reviewed, and evaluated independently by two reviewers. The meta-analysis tool, Review Manager (RevMan Copenhagen Version 5.4.1), was used to record the extracted data for the meta-analysis. Moran's I 2 and a funnel plot were utilized to measure heterogeneity, and publication bias was investigated. A 95% confidence interval (CI) and overall risk difference (RD) were estimated using a random-effects model.
RESULT AND DISCUSSION: As a consequence of the search efforts, a total of 46 articles were selected for inclusion in the systematic review and meta-analysis. This review was divided into five major themes, based on a thematic analysis: (i) hatching rate, (ii) development time, (iii) longevity, (iv) survival rate, and (v) wing morphology. In addition, the development time, survival rate, and wing morphology revealed significantly higher risk differences between the maximum and minimum temperatures (RD: 0.26, 95% CI: 0.16, 0.36; p = < 0.00001; RD: 0.10, 95% CI: 0.05, 0.14; p < 0.0001; and RD: 0.07, 95% CI: 0.02, 0.12; p = 0.006, respectively). This study makes several substantial contributions to the body of knowledge and to practical applications. Finally, a number of recommendations are made at the conclusion of this research for the future reference of researchers.

Matched MeSH terms: Longevity
Fulltext An Energy-Efficient Mobile Sink-Based Unequal Clustering Mechanism for WSNs

Gharaei N, Abu Bakar K, Mohd Hashim SZ, Hosseingholi Pourasl A, Siraj M, Darwish T

Sensors (Basel), 2017 Aug 11;17(8).
PMID: 28800121 DOI: 10.3390/s17081858

Network lifetime and energy efficiency are crucial performance metrics used to evaluate wireless sensor networks (WSNs). Decreasing and balancing the energy consumption of nodes can be employed to increase network lifetime. In cluster-based WSNs, one objective of applying clustering is to decrease the energy consumption of the network. In fact, the clustering technique will be considered effective if the energy consumed by sensor nodes decreases after applying clustering, however, this aim will not be achieved if the cluster size is not properly chosen. Therefore, in this paper, the energy consumption of nodes, before clustering, is considered to determine the optimal cluster size. A two-stage Genetic Algorithm (GA) is employed to determine the optimal interval of cluster size and derive the exact value from the interval. Furthermore, the energy hole is an inherent problem which leads to a remarkable decrease in the network's lifespan. This problem stems from the asynchronous energy depletion of nodes located in different layers of the network. For this reason, we propose Circular Motion of Mobile-Sink with Varied Velocity Algorithm (CM2SV2) to balance the energy consumption ratio of cluster heads (CH). According to the results, these strategies could largely increase the network's lifetime by decreasing the energy consumption of sensors and balancing the energy consumption among CHs.

Matched MeSH terms: Longevity
Analysis of Mortality Improvement on the Pension Cost Due to Aging Population

Rose Irnawaty Ibrahim, Norazmir Mohd Nordin

MATEMATIKA, 2020;36(3):209-216.
MyJurnal

Aging is a good indicator in demographic and health areas as the lifespan
of the elderly population increases. Based on the government’s Economic Outlook 2019,
it was found that an aging population would increase the government pension payments
as the pensioners and their beneficiaries have longer life expectancy. Due to mortality
rates decreasing over time, the life expectancy tends to increase in the future. The
aims of this study are to forecast the mortality rates in the years 2020 and 2025 using
the Heligman-Pollard model and then analyse the effect of mortality improvement on
the pension cost (annuity factor) for the Malaysian population. However, this study
only focuses on estimating the annuity factor using life annuities through the forecasted
mortality rates. The findings indicated that the pension cost is expected to increase if
the life expectancy of the Malaysian population increases due to the aging population
the near future. Thus, to reduce pension costs and help the pensioners from insufficient
financial income, the government needs to consider an extension of the retirement age in
future.

Matched MeSH terms: Longevity
Anti-ageing effects of FDA-approved medicines: a focused review

Thanapairoje K, Junsiritrakhoon S, Wichaiyo S, Osman MA, Supharattanasitthi W

J Basic Clin Physiol Pharmacol, 2023 May 01;34(3):277-289.
PMID: 36631934 DOI: 10.1515/jbcpp-2022-0242

Ageing is the process generated by senescent cells, free radicals, inflammation and other relevant factors. Ageing contributes to age-related diseases that affect the quality of life. People are interested in anti-ageing intervention and many scientists attempt to search for anti-ageing medicines. This review focused on describing in vivo anti-ageing activity of US-FDA-approved drugs and found that alogliptin, canagliflozin and metformin might produce anti-ageing activity via AMPK activation. Rapamycin and canagliflozin are capable to inhibit mTOR to promote lifespan. Atracurium, carnitine and statins act as DAF-16 activators, which potentially contribute to anti-ageing activity. Hydralazine, lisinopril, rosiglitazone and zidovudine may help stabilize genomic integrity to prolong life expectancy. Other indirect mechanisms, including insulin-lowering effect by acarbose and calcium channel blocking activity by verapamil may also promote longevity. Interestingly, some drugs (i.e., canagliflozin, metformin, rapamycin and acarbose) are likely to demonstrate a lifespan-promoting effect predominantly in male animals. These pre-clinical data might provide mechanistic and phenotypic perspectives to better understand the targets of anti-ageing interventions.

Matched MeSH terms: Longevity/genetics
Fulltext Are the Poor Dying Younger in Malaysia? An Examination of the Socioeconomic Gradient in Mortality

Mariapun J, Hairi NN, Ng CW

PLoS One, 2016;11(6):e0158685.
PMID: 27362581 DOI: 10.1371/journal.pone.0158685

INTRODUCTION: Socioeconomic inequalities in health represent unfairness in the health distribution of a population. Efforts to produce information on mortality distributions in many low and middle income countries (LMICs) are mostly hampered by lack of data disaggregated by socioeconomic groups. In this paper we describe how mortality statistics obtained from multiple data sources were combined to provide an evaluation of the socioeconomic distribution of mortality in Malaysia, a LMIC located in the Asia Pacific region.
METHODS: This study has an ecological design. As a measure of socioeconomic status, we used principal component analysis to construct a socioeconomic index using census data. Districts were ranked according to the standardised median index of households and assigned to each individual in the 5-year mortality data. The mortality indicators of interest were potential years of life lost (PYLL), standardised mortality ratio (SMR), infant mortality rate (IMR) and under-5 mortality rate (U5MR). Both socioeconomic status and mortality outcomes were used compute the concentration index which provided the summary measure of the magnitude of inequality.
RESULTS: Socially disadvantaged districts were found to have worse mortality outcomes compared to more advantaged districts. The values of the concentration index for the overall population of the Peninsula are C = -0.1334 (95% CI: -0.1605 to -0.1063) for the PYLL, C = -0.0685 (95% CI: -0.0928 to -0.0441) for the SMR, C = -0.0997 (95% CI: -0.1343 to -0.0652) for the IMR and C = -0.1207 (95% CI: -0.1523 to -0.0891) for the U5MR. Mortality outcomes within ethnic groups were also found to be less favourable among the poor.
CONCLUSION: The findings of this study suggest that socioeconomic inequalities disfavouring the poor exist in Malaysia.

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
Fulltext Assessment of clinical and radiographic status of crowned teeth

Nurul Farahah Bahari, Nur Iffah Izzaty Jamal, John, Jacob

Ann Dent, 2019;26(1):8-14.
MyJurnal

This cross sectional study investigated the clinical and radiographic status of crowned teeth with and without root canal treatment. The study used secondary data from records of patients who received crown treatment at the Faculty of Dentistry, University of Malaya before 2015 and walk-in patients attending the primary care clinic between July - December 2016. The inclusion criterion was crown fitted for more than 12 months. Once identified, the patients were assessed for clinical and radiographic status. Data were entered into and analysed using SPSS Version 20 software. A total of 66 crowns [35 root canal treated (RCT) and 31 non-root canal treated (n-RCT)] were identified. Chi-square test was carried out to determine the health of crowned teeth and for its longevity in the oral cavity. There were 43 crowns (46.5% RCT; 53.5% n-RCT) with plaque accumulation, 15 (66.7% RCT; 33.3% n-RCT) with gingival swelling/recession, 17 (46.5% RCT; 53.5% n-RCT) with widening of the periodontal ligament, 13 (53.8% RCT; 46.2% n-RCT) with bone loss and 5 (60% RCT; 40% n-RCT) crowns with periapical lesion. There was no statistically significant difference except for poorer alveolar bone condition for crowns that have been in the mouth for >10 years. Based on the study, no significant adverse pulpal involvement between crown with RCT and crown without RCT was observed.

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
Biological aspects of Myopopone castanea on it's prey Oryctes rhinoceros larvae

Widihastuty, Tobing MC, Marheni, Kuswardani RA, Fudholi A

J Insect Physiol, 2020 07 17;125:104089.
PMID: 32687849 DOI: 10.1016/j.jinsphys.2020.104089

Ants are social insects with some significant roles in the ecosystem, including acting as predators for various insect pests. Myopopone castanea ants is a predatorfor the larvae of Oryctes rhinoceros pest. The existence of a similar niche of life between M. castanea ants and O. rhinoceros larvae opens an excellent opportunity to utilize these ants as biological agents. The research was conducted to study some aspects biology of M. castanea so that later it can be applied to mass rearing of natural enemies in the laboratory. The study was conducted by maintaining 50 eggs of M. castanea ant. Then, the eggs placed on two pieces of decayed palm oil stem together with twenty individual worker ants and ten individual end instar larvae. It needs five replications for the experiment. The results showed that egg stadia length was 13.8 days. It found five instars within M. castanea ant larvae with varying lengths of each stage. It takes 17.2 days for worker ant pupae to go through stadia pupa and 17.9 days for female ant pupae. The survival rate of M. castanea ant life from eggs until imago is 56.4%, which means that from several groups of eggs laid by queen ants, only about half have succeeded in becoming ant imago.

Matched MeSH terms: Longevity
Fulltext Caries preventive interventions in community-dwelling elders: a systematic review

Eleena Mohd Yusof, Mei, May Lei, Walls, Angus

Compendium of Oral Science, 2018;5(1):1-17.
MyJurnal

Objective: To conduct a systematic review of identifying the clinical efficacy of caries preventive interventions in community-dwelling elders. Background: As the human lifespan increases, the elders are known to retain their teeth for longer. Therefore, the need to uncover effective ways of preventing caries among this age group is relevant. Methods: A search was conducted using four databases: Cochrane, MEDLINE, EMBASE and Web of Science using the keywords (caries OR demineralization) AND prevention AND (adult OR aged). The titles and abstracts were initially screened for the use of caries prevention interventions. Studies were excluded based on the predetermined criteria. The full texts of the remaining studies were then evaluated. Results: Of 6952 articles identified from the search, fifty full texts were evaluated. Finally, ten studies were analyzed. One study found rinsing with 0.05% of NaF twice daily resulted in lower coronal caries increment. Another study reported the use of 1,100 ppm of NaF dentifrice twice daily showed lower percentage of coronal and root caries. A reduction of root caries was observed from using 5,000 ppm fluoridated toothpaste twice daily, annual professional 38% SDF solution application, six-monthly professional cleaning and APF gel application. The use of 0.12% CHX rinse and xylitol chewing gum did not show reduction of caries incidence. Conclusion: Toothbrushing with 5,000 ppm of NaF dentifrice, rinsing with 0.05% NaF, professional application of 38% SDF solution and APF gel may be effective at preventing caries among the elders.

Matched MeSH terms: Longevity
Fulltext Changes in white matter fiber density and morphology across the adult lifespan: A cross-sectional fixel-based analysis

Choy SW, Bagarinao E, Watanabe H, Ho ETW, Maesawa S, Mori D, et al.

Hum Brain Mapp, 2020 08 15;41(12):3198-3211.
PMID: 32304267 DOI: 10.1002/hbm.25008

White matter (WM) fiber bundles change dynamically with age. These changes could be driven by alterations in axonal diameter, axonal density, and myelin content. In this study, we applied a novel fixel-based analysis (FBA) framework to examine these changes throughout the adult lifespan. Using diffusion-weighted images from a cohort of 293 healthy volunteers (89 males/204 females) from ages 21 to 86 years old, we performed FBA to analyze age-related changes in microscopic fiber density (FD) and macroscopic fiber morphology (fiber cross section [FC]). Our results showed significant and widespread age-related alterations in FD and FC across the whole brain. Interestingly, some fiber bundles such as the anterior thalamic radiation, corpus callosum, and superior longitudinal fasciculus only showed significant negative relationship with age in FD values, but not in FC. On the other hand, some segments of the cerebello-thalamo-cortical pathway only showed significant negative relationship with age in FC, but not in FD. Analysis at the tract-level also showed that major fiber tract groups predominantly distributed in the frontal lobe (cingulum, forceps minor) exhibited greater vulnerability to the aging process than the others. Differences in FC and the combined measure of FD and cross section values observed between sexes were mostly driven by differences in brain sizes although male participants tended to exhibit steeper negative linear relationship with age in FD as compared to female participants. Overall, these findings provide further insights into the structural changes the brain's WM undergoes due to the aging process.

Matched MeSH terms: Longevity
Child survivorship estimation: methods and data analysis

Feeney G

Asian Pac Popul Forum, 1991;5(2-3):51-5, 76-87.
PMID: 12343438

"The past 20 years have seen extensive elaboration, refinement, and application of the original Brass method for estimating infant and child mortality from child survivorship data. This experience has confirmed the overall usefulness of the methods beyond question, but it has also shown that...estimates must be analyzed in relation to other relevant information before useful conclusions about the level and trend of mortality can be drawn.... This article aims to illustrate the importance of data analysis through a series of examples, including data for the Eastern Malaysian state of Sarawak, Mexico, Thailand, and Indonesia. Specific maneuvers include plotting completed parity distributions and 'time-plotting' mean numbers of children ever born from successive censuses. A substantive conclusion of general interest is that data for older women are not so widely defective as generally supposed."

Matched MeSH terms: Longevity
Fulltext Clinical nutrition in East Asia and the Pacific

Darnton-Hill I, Cavalli-Sforza LT, Volmanen PV

Asia Pac J Clin Nutr, 1992 Mar;1(1):27-36.
PMID: 24323002

Identifying the nutrition problems of Asia and the Pacific is made difficult by the enormous geographic, socioeconomic and cultural diversity that exists in these areas. With increasing longevity and reduced infant mortality, the more chronic diseases are becoming increasingly important. For almost 90% of the countries that keep such data in the Western Pacific Region of WHO, at least three of the five leading causes of death are noncommunicable diseases. Nevertheless undernutrition is still the most important nutritional problem in the Region. Even though there have been some encouraging declines in the proportion of malnourished under 5-year-olds, increasing populations have meant the actual numbers have not declined. Vitamin A deficiency, iodine deficiency disorders and iron deficiency anaemia remain major public health problems in many countries. There is evidence that vitamin A deficiency is appearing in countries in which it has not previously been a problem. New challenges are occurring, such as childhood obesity, the susceptibility of undernourished populations to the human immunodeficiency virus and the increase in noncommunicable diseases. The three arms of clinical nutrition: therapeutic, research and public health will need to work closely to meet the considerable and continuing threat posed by the nutrition-related diseases.

Matched MeSH terms: Longevity
Comparative toxicity of nine metals to two Malaysian aquatic dipterian larvae with reference to temperature variation

Vedamanikam VJ, Shazilli NA

Bull Environ Contam Toxicol, 2008 Jun;80(6):516-20.
PMID: 18414763 DOI: 10.1007/s00128-008-9413-x

A study was conducted to determine the suitability of using selected aquatic dipterian larvae for biomonitoring bioassays. The organisms included a member of the biting midge family that was identified as Culicoides furens and a member of the non-biting midge family, identified as Chironomus plumosus. Median lethal toxicity tests were conducted to observe the variation between metal sensitivities between the two larval forms and how variations in temperature could affect the experimental setup. Nine heavy metals were used in the study. It was observed that the 96 h LC(50) (in mg/L) for the different metals was found to be Zn-16.21 (18.55 +/- 13.87); Cr-0.96 (1.08 +/- 0.84); Ag-4.22 (6.87 +/- 1.57); Ni-0.42 (0.59 +/- 0.25); Hg-0.42 (0.59 +/- 0.25); Pb-16.21 (18.31 +/- 14.11); Cu-42.24 (45.18 +/- 39.30); Mn-4.22 (7.19 +/- 1.25); Cd-0.42 (0.59 +/- 0.25) for the Chironomus plumosus and Zn-4.22 (6.56 +/- 1.88); Cr-0.42 (0.54 +/- 0.30); Ag-0.42 (0.54 +/- 0.30); Ni-0.42 (0.54 +/- 0.30); Hg-0.04 (0.07 +/- 0.01); Pb-0.42 (0.54 +/- 0.30); Cu-42.24 (45.18 +/- 39.30); Mn-4.22 (6.56 +/- 1.88); Cd-0.42 (0.54 +/- 0.30) in the case of the Culicoides furens. With temperature as a variable the LC(50) values were observed to increase from 2.51 mg/L at 10 degrees C to 4.22 ppm at 30 degrees C and to reduce slightly to 3.72 mg/L at 35 degrees C as seen in the case of Zn. It was also observed that at 40 degrees C thermal toxicity and chemical toxicity overlapped as 100% mortality was observed in the controls. This trend was observed in all metals for both C. plumosus and C. furens. Thus indicating temperature played an important role in determining LC(50) values of toxicants.

Matched MeSH terms: Longevity/drug effects
Comparison of protein-free defined media, and effect of L-cysteine and ascorbic acid supplementation on viability of axenic Entamoeba histolytica

Wong WK, Tan ZN, Lim BH, Mohamed Z, Olivos-Garcia A, Noordin R

Parasitol Res, 2011 Feb;108(2):425-30.
PMID: 20922423 DOI: 10.1007/s00436-010-2083-8

Entamoeba histolytica is the etiologic agent for amoebiasis. The excretory-secretory (ES) products of the trophozoites contain virulence factors and antigens useful for diagnostic applications. Contaminants from serum supplements and dead trophozoites impede analysis of ES. Therefore, a protein-free medium that can sustain maximum viability of E. histolytica trophozoites for the longest time duration will enable collection of contaminant-free and higher yield of ES products. In the present study, we compared the efficacy of four types of media in maintaining ≥ 95% trophozoite viability namely Roswell Memorial Park Institute (RPMI-1640), Dulbecco's Modified Eagle Medium (DMEM), phosphate-buffered saline for amoeba (PBS-A), and Hank's balanced salt solution (HBSS). Concurrently, the effect of adding L: -cysteine and ascorbic acid (C&A) to each medium on the parasite viability was also compared. DMEM and RPMI 1640 showed higher viabilities as compared to PBS-A and HBSS. Only RPMI 1640 showed no statistical difference with the control medium for the first 4 h, however the ≥ 95% viability was only maintained for the first 2 h. The other protein-free media showed differences from the serum- and vitamin-free TYI-S-33 control media even after 1 h of incubation. When supplemented with C&A, all media were found to sustain higher trophozoite viabilities than those without the supplements. HBSS-C&A, DMEM-C&A, and RPMI 1640-C&A demonstrated no difference (P>0.05) in parasite viabilities when compared with the control medium throughout the 8-h incubation period. DMEM-C&A showed an eightfold increment in time duration of sustaining ≥ 95% parasite viability, i.e. 8 h, as compared to DMEM alone. Both RPMI 1640-C&A and HBSS-C&A revealed fourfold and threefold increments (i.e., 8 and 6 h, respectively), whereas PBS-A-C&A showed only one fold improvement (i.e., 2 h) as compared to the respective media without C&A. Thus, C&A-supplemented DMEM or RPMI are recommended for collection of ES products.

Matched MeSH terms: Longevity/drug effects
Could hypertension possibly be adaptive?

Prakash ES, Fink GD

Clin Exp Pharmacol Physiol, 2010 Feb;37(2):e99-e106.
PMID: 19719749 DOI: 10.1111/j.1440-1681.2009.05284.x

1. We believe that the ultimate goal of cardiovascular regulatory mechanisms is not the regulation of arterial blood pressure (BP), but the maintenance of tissue blood flows commensurate with metabolic requirements. Thus, elevated BP can potentially contribute to optimizing tissue blood flows under select circumstances; for example, when there are primary defects in autoregulation of tissue blood flows. 2. The hypothesis that a primary defect in autoregulation of tissue blood flows may be responsible for the development of hypertension is presented. It is argued that, in this context, at least part of the rise in BP may be reflexly driven by a 'metaboreflex', a homeostatic mechanism acting to regulate tissue blood flows. 3. We argue that in the context of primary defects in autoregulation of tissue blood flows, the ability to generate and sustain a hypertensive phenotype increases the lifespan of species (i.e. if it were not for this adaptive hypertensive phenotype, death due to circulatory failure would occur much earlier). 4. Experimental and clinical evidence that indirectly supports the hypothesis is reviewed briefly and a means for testing this hypothesis is suggested.

Matched MeSH terms: Longevity/physiology*
Fulltext Crocodiles and alligators: physicians' answer to cancer?

Khan NA, Soopramanien M, Siddiqui R

Curr Oncol, 2019 06;26(3):186.
PMID: 31285664 DOI: 10.3747/co.26.4855
Matched MeSH terms: Longevity

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