population doubling
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Author(s):  
Thokchom Shitarjit Singh ◽  
O.R. Sathyamoorthy ◽  
Soundian Eswari ◽  
Sabiha Hayath Basha ◽  
M. Parthiban

Background: Mesenchymal stem cells are well known for their self-renewal capacity and ability to differentiate into multiple cell lineages. The aim of the study was to develop a simple technique for isolation of mesenchymal stem cells from porcine adipose tissue and to study the morphometric characteristics of porcine mesenchymal stem cells. Methods: Porcine adipose derived mesenchymal stem cells were isolated in vitro by using collagenase type II enzyme. Cell yield and viability of the cells were calculated by using trypan blue exclusion method using Neubauer’s chamber. Characterization of MSCs were done by using specific cell markers. The morphological changes, morphometry were analysed in culture using Leishman’s stain. The cell doubling (CD) and Population doubling time (PDT) were also calculated. Result: The isolated adherent cells start forming colony and demonstrated an elongated, round and spindle like fibroblastic morphology by day 1. Almost 80-90 per cent confluency was attained on day 8-9 after the initial seeding and was reduced to day 3-4 in the subsequent passages. RT-PCR reactions revealed positive expression of mesenchymal stem cell markers CD44, CD73 and negative expression of CD34, a hematopoietic cell surface marker. Immunocytochemistry also revealed positive expression for CD44 and negative for CD34. In morphometric studies, the cell length, nucleus length, cell width and nucleus width were increased between 24 and 48 hours in both P2 and P3.


2022 ◽  
Vol 25 ◽  
pp. 69-76
Author(s):  
Leyla Anari ◽  
Davood Mehrabani ◽  
Mahboobeh Nasiri ◽  
Shahrokh Zare ◽  
Iman Jamhiri ◽  
...  

Purpose: Among abused substances, methamphetamine is a psychostimulant drug widely used recreationally with public health importance. This study investigated the effect of methamphetamine on proliferation, differentiation, and apoptosis of human adipose tissue stem cells (AdSCs). Methods: AdSCs were isolated from human abdominal adipose tissue and were characterized for mesenchymal properties and growth kinetics. MTT assay was undertaken to assess methamphetamine toxicity on proliferation and differentiation properties and apoptosis of hAdSCs. Results: Isolated cells were shown to have mesenchymal properties and a population doubling time (PDT) of 40.1 h. Following methamphetamine treatment, expressions of KI-67 and TPX2 as proliferation genes and Col1A1 and PPARg as differentiation genes decreased. Methamphetamine administration increased the expression of Bax and decreased Bcl-2 genes responsible for apoptosis. Conclusions: Our data suggested when AdSCs were exposed to methamphetamine, it decreased proliferation and differentiation properties of stem cells together with an increase in apoptosis. These findings can be added to the literature, especially when methamphetamine is used recreationally for weight loss purposes.


2022 ◽  
Author(s):  
Joo Youn Lee ◽  
Min Hee Kang ◽  
Ji Eun Jang ◽  
Jeong Eon Lee ◽  
Yuyeong Yang ◽  
...  

Abstract Stem cells are attractive candidates for the regeneration of tissue and organ. Mesenchymal stem cells (MSCs) have been extensively investigated for their potential applications in regenerative medicine and cell therapy. For developing effective stem cell therapy, the mass production of consistent quality cells is required. The cell culture medium is the most critical aspect of the mass production of qualified stem cells. Classically, fetal bovine serum (FBS) has been used as a culture supplement for MSCs. Due to the undefined and heterologous composition of animal origin components in FBS, efforts to replace animal-derived components with non-animal-derived substances led to safe serum free media (SFM). Adipose derived mesenchymal stem cells (ADSCs) cultivated in SFM provided a more stable population doubling time (PDT) to later passage and more cells in a shorter time compared to FBS containing media. ADSCs cultivated in SFM had lower cellular senescence, lower immunogenicity, and higher genetic stability than ADSCs cultivated in FBS containing media. Differential expression analysis of mRNAs and proteins showed that the expression of genes related with apoptosis, immune response, and inflammatory response were significantly up-regulated in ADSCs cultivated in FBS containing media. ADSCs cultivated in SFM showed similar therapeutic efficacy in an acute pancreatitis mouse model to ADSCs cultivated in FBS containing media. Consideration of clinical trials, not only pre-clinical trial, suggests that cultivation of MSCs using SFM might offer more safe cell therapeutics as well as repeated administration due to low immunogenicity.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shinichiro Chuma ◽  
Mito Kanatsu-Shinohara ◽  
Ami Katanaya ◽  
Mihoko Hosokawa ◽  
Takashi Shinohara

AbstractGermline mutations underlie genetic diversity and species evolution. Previous studies have assessed the theoretical mutation rates and spectra in germ cells mostly by analyzing genetic markers and reporter genes in populations and pedigrees. This study reported the direct measurement of germline mutations by whole-genome sequencing of cultured spermatogonial stem cells in mice, namely germline stem (GS) cells, together with multipotent GS (mGS) cells that spontaneously dedifferentiated from GS cells. GS cells produce functional sperm that can generate offspring by transplantation into seminiferous tubules, whereas mGS cells contribute to germline chimeras by microinjection into blastocysts in a manner similar to embryonic stem cells. The estimated mutation rate of GS and mGS cells was approximately 0.22 × 10−9 and 1.0 × 10−9 per base per cell population doubling, respectively, indicating that GS cells have a lower mutation rate compared to mGS cells. GS and mGS cells also showed distinct mutation patterns, with C-to-T transition as the most frequent in GS cells and C-to-A transversion as the most predominant in mGS cells. By karyotype analysis, GS cells showed recurrent trisomy of chromosomes 15 and 16, whereas mGS cells frequently exhibited chromosomes 1, 6, 8, and 11 amplifications, suggesting that distinct chromosomal abnormalities confer a selective growth advantage for each cell type in vitro. These data provide the basis for studying germline mutations and a foundation for the future utilization of GS cells for reproductive technology and clinical applications.


2021 ◽  
Vol 16 (12) ◽  
pp. 24-29
Author(s):  
Vinutha Eshwara Swamy ◽  
Nikhil Shetty ◽  
Jayaprakasha Shetty ◽  
Veena Shetty ◽  
Tonita Noronha ◽  
...  

Human dermal stem cells (DSCs) have generated significant interest in the field of regenerative medicine due to their prospects of autologous transplantation. The present study evaluated the growth kinetics and phenotypic markers expression in human DSCs. The primary cultures of DSCs (n=3) were established by explant culture and characterization of the cells was carried out by assessing morphology, viability, proliferation rate, population doubling time (PDT), cell cycle status and the expression of cell surface markers such as CD29, CD73, CD90 and CD166. The cells released from tissue explants showed spindleshaped fibroblast morphology with the mean percentage viability varying between 93.43% and 100% from passages 1 to 4. DSCs displayed a strong and steady proliferative potential with an average PDT of 42.55 hrs. Cell cycle profile of DSCs demonstrated the majority of cells (59.80% to 76.29%) at G0/G1 phase. Further, the phenotypic profile of markers confirmed the stromal origin of DSCs by exhibiting positivity for CD29, CD73, CD90 and CD166. In conclusion, the growth kinetics and expression of phenotypic markers are consistent with the notion that skin dermis contains a population of stem cells and can serve as a potential autologous source for therapeutic applications.


2021 ◽  
Author(s):  
Mahnaz Tashakori ◽  
Fatemeh Asadi ◽  
Faezeh-Sadat Khorram ◽  
Azita Manshoori ◽  
Ali Hosseini-Chegeni ◽  
...  

Abstract BackgroundMesenchymal stem cells (MSCs), derived from various tissues, have served as a promising source of cells in clinic and regenerative medicine. Umbilical cord-Wharton’s jelly (WJ-MSCs)-derived MSCs exhibit advantages over those from adult tissues, such as no ethical concerns, shorter population doubling time, broad differentiation potential, readily available non-invasive source, prolonged maintenance of stemness properties. Material and methodsThe aim of this study was to evaluate the effect of MRI (1.5 T, 10 min) on stemness gene expression patterns (OCT-4, SOX-2, NANOG) of WJ-MSCs. In addition, we assessed cell viability, growth kinetics and apoptosis of WJ-MSCs after MRI treatment. ResultsThe quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) data showed that transcript levels of SOX-2, NANOG in MRI-treated WJ-MSCs were increased 32- and 213-fold, respectively. MTT assay was performed at 24, 48, and 72 hours post-treatment and the viability was not significantly difference between two groups. The doubling time of MRI group was markedly higher than control group. In addition, the colony formation ability of WJ-MSCs after MRI treatment significantly increased. Furthermore, no change in apoptosis was seen before or after MRI treatment. ConclusionsOur results suggest the use of MRI can improve quality of MSCs and may enhance the efficacy of mesenchymal stem cell-based therapies.


Author(s):  
Suqin Shang ◽  
Yun Chang ◽  
Wei-Zhen Li ◽  
Wang Chang-Qing ◽  
Nie Peng-Cheng

AbstractThe present study was conducted to evaluate sublethal effects of B-azolemiteacrylic on the two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae). Female adults of T. urticae were exposed to LC10 and LC30 of the acaricide, and the effects on treated females and their offspring were evaluated. The results showed that the fecundity of F0 female adults treated with LC10 and LC30 of B-azolemiteacrylic was reduced by 30.9 and 39.2%, respectively. Longevity and oviposition period of the females were significantly reduced as well. The developmental duration of egg and deutonymph stage of the F1 generation were not significantly different from that of the control. The protonymph stage after LC30 treatment lasted significantly longer, whereas the larva, deutonymph and female stage were significantly shorter than the control. The oviposition period of the F1 generation was significantly shortened, the fecundity of each female decreased significantly, and the ratio of female-to-male was reduced too. Moreover, the average generation period of T. urticae after LC10 and LC30 treatments was shorter than that of the control, and the net production rate (R0), intrinsic rate of increase (rm) and finite rate of increase (λ) were all reduced by 33.3, 7.5 and 1.9% (LC10 treatment) and by 51.3, 14.8 and 3.6% (LC30 treatment), respectively. The population doubling time was prolonged by 7.5 and 14.8% after LC10 and LC30 treatments, respectively, compared with the control. These results indicate that B-azolemiteacrylic may effectively inhibit the development rate of the F0 and F1 populations of T. urticae, which will help design integrated strategies for the comprehensive control of T. urticae and rational use of pesticides in the field.


2021 ◽  
Vol 66 (5) ◽  
pp. 85-90
Author(s):  
P. Okatenko ◽  
E. Fomin ◽  
E. Denisova ◽  
I. Kuznetsova ◽  
M. Sokolnikov ◽  
...  

Purpose: The analysis of the structure of malignant neoplasms (MN) incidence among the population in the city Ozyorsk, located near Mayak Production Association, based on the information from the territorial cancer registry. Materials and methods: There were 14681 first diagnosed cases of malignant neoplasms at the period from 1948 to 2016 in the territorial cancer registry of Ozyorsk. The diagnoses were verified by all available medical documents. The structure of MN incidence, vital status of diseased people, age in a year of diagnostics, rank distribution of the basic localizations were studied. Results: For 70 years period of follow-up there were 7676 cases from 14681 of MN incidence cases during the last 17 years (from 2000 to 2017) – as much as for the previous 51 years of follow-up from 1948 to 1999 (7005 cases). In the MN structure solid cancer constitutes 94.5 %, hemoblastoses – 5.5 %. As at December 31, 2016 23.3 % of the diseased people were alive, 75.2 % died from all causes, 1.5 % lost to follow-up. The cause of 80,6 % deaths was MN. Age in the year of diagnostics constitutes 61,7 years. 75.8 % diagnoses have morphological confirmation. During the entire period of follow-up first three places belong to lung cancer, gastric cancer and prostate cancer for males; breast cancer, gastric cancer and colon cancer for females in the MN structure. Conclusions: During the period from 1948 to 2016 the growth of the first diagnosed MN cases among the population of Ozyorsk was a result of the population doubling and a fourfold increase of the citizens over the age of 50. Developed and supported cancer registry allows to analyze and partially control oncological situation in the closed cities of Rosatom.


Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2643
Author(s):  
Lily R. Zehfus ◽  
Zoe E. Gillespie ◽  
Carla Almendáriz-Palacios ◽  
Nicholas H. Low ◽  
Christopher H. Eskiw

It is generally accepted that dietary phenolics from fruits are of significant importance to human health. Unfortunately, there is minimal published data on how differences in phenolic structure(s) impact biological pathways at cellular and molecular levels. We observed that haskap berry extracts isolated with ethanol:formic acid:water or phenolic subclass fractions separated using different concentrations of ethanol (40% and 100%) impacted cell growth in a positive manner. All fractions and extracts significantly increased population doubling times. All extracts and fractions reduced intracellular free radicals; however, there were differences in these effects, indicating different abilities to scavenge free radicals. The extracts and fractions also exhibited differing impacts on transcripts encoding the antioxidant enzymes (CAT, SOD1, GPX1, GSS and HMOX1) and the phosphorylation state of nuclear factor-κB (NF-κB). We further observed that extracts and fractions containing different phenolic structures had divergent impacts on the mammalian target of rapamycin (mTOR) and sirtuin 1 (SIRT1). siRNA-mediated knockdown of SIRT1 transcripts demonstrated that this enzyme is key to eliciting haskap phenolic(s) impact on cells. We postulate that phenolic synergism is of significant importance when evaluating their dietary impact.


2021 ◽  
Author(s):  
Søren Vedel ◽  
Andrej Košmrlj ◽  
Harry Nunns ◽  
Ala Trusina

Abstract By diversifying, cells in a clonal population can together overcome the limits of individuals. Diversity in single-cell growth rates allows the population to survive environmental stresses, such as antibiotics, and grow faster than undiversified population. These functional cell-cell variations can arise stochastically, from noise in biochemical reactions, or deterministically, by asymmetrically distributing damaged components. While each of the mechanism is well understood, the effect of the combined mechanisms is unclear. To evaluate the contribution of the deterministic component we mapped the growing population to the Ising model. Model results, confirmed by simulations and experimental data, show that cell-cell variations increase near-linearly with stress. As a consequence, we predict that the entropic gain — the gain in population doubling time compared to an “average” cell — is primarily stochastic at low stress but crosses over to deterministic at higher stresses. Furthermore, we find that while the deterministic component minimizes population damage, stochastic variations antagonize this effect. Together our results may help identifying stress-tolerant pathogenic cells and thus inspire novel antibiotic strategies.


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