Doubling Time Research Articles

Comparative demography of two wild cladoceran species, Alona quadrangularis and Scapholeberis mucronata, collected in western Washington state and reared under laboratory conditions

AbstractPopulations of two cladoceran species, Alona quadrangularis and Scapholeberis mucronata, were collected from a pond in Puyallup, Washington, and reared under controlled laboratory conditions. Life tables were developed for each species under the same environmental conditions and feeding regimen to develop basic demographic data. We also compared the major demographic parameters of these two wild species with those of several cladoceran species that are commonly used in laboratory research, Daphnia pulex, D. magna, and Ceriodaphnia dubia. Compared to A. quadrangularis, S. mucronata had a much higher net reproductive rate (R0), a longer generation time (T), but a similar intrinsic rate of increase (rm), similar finite rate of increase, similar doubling time (DT), and a lower birth rate (b). Both wild species had lower R0, shorter T, and higher b than in D. pulex, D. magna, and C. dubia. Results of this study showed that demographic rates differed between A. quadrangularis and S. mucronata, and differed from those reported for the other three laboratory species. These results suggest that data developed for commonly used cladoceran species in the laboratory should not be used to make generalizations about effects on wild species.

Biological performance of Bollgard II® Bt-resistant vs susceptible population of pink bollworm, Pectinophora gossypiella (Saunders) on non-toxic diet

BackgroundThe pink bollworm, Pectinophora gossypiella (Saunders), is a devastating global pest of cotton that has caused substantial economic damage to Bt Bollgard-II® cotton plants in recent years due to the evolution of Bt resistance. The associated fitness cost is assumed to be one of the factors delaying the development of resistance against Bt transgenic crops. Hence, the present study was undertaken to assess the biological performance of pink bollworms by comparing the life history and demographic parameters of a resistant (Field-R) and susceptible (Lab-S) population.ResultsProlonged larval duration (23.40 days in Field-R vs 18.80 days in Lab-S population), total life cycle (male = 50.00 vs 42.80 days; female = 53.60 vs 46.20 days), reduced fecundity (100.60 vs 154.20 eggs/female) and fertility (88.00 vs 138.00 fertile eggs/female) was observed. The demographic parameters indicated a significant reduction in the net reproductive rate (184.27 vs 276.72), innate capacity for increase in number (0.11 vs 0.15), finite rate of increase in number (1.12 vs 1.16 female progenies produced/female/day), weekly multiplication rate (2.16 vs 2.86), potential fecundity (545.06 vs 634.11 eggs), number of hypothetical F2 females (33 955.65 vs 76 572.41), but longer mean length of generation (47.54 vs 37.74 days) and population doubling time (6.30 vs 4.62 days) in Field-R compared with Lab-S population. A stage-specific life table demonstrated the differences in survival rates between susceptible and resistant populations at various life stages, with the resistant population having higher generation mortality (0.22 vs 0.19).ConclusionsThe study confirms the involvement of fitness costs associated with Bt resistance in P. gossypiella. Despite reduced reproductive fitness, the resistant population tried prolonging the larval stage as a compensatory mechanism to repair the damaged host tissues due to Bt intoxication and for accumulation of enough nutrient reserves for normal pupation and adult emergence. Presence of a high proportion of double Bt-resistant larvae in the field coupled with continued noncompliance with refug planting certainly favours the flaring up of this monophagous pest despite the observed fitness costs. The resistance cannot be effectively reversed unless suitable alternative management strategies are deployed.

Fitness Costs in Diamondback Moth Plutella xylostella (L.) (Lepidoptera: Plutellidae) Resistant to Lufenuron, A Chitin-Synthesis Inhibitor Insecticide

The diamondback moth (DBM), Plutella xylostella, is the main pest of Brassicas crops worldwide, and its recorded resistance to 101 active ingredients indicates it is difficult to control. The purpose of this study was to investigate the hypothesis that P. xylostella has fitness costs associated with its resistance to lufenuron, a chitin-synthesis inhibitor insecticide. Thus, concentration–mortality bioassays were performed for susceptible (REC-S), resistant (BZR-R) populations, their progenies F1 and F1′, and one established population without selection pressure (BZR-Rns) after four generations. A fertility life table was used to assess the biological performance of the REC-S and BZR-R. BZR-Rns of P. xylostella. The larval stage, longevity, and survival differed between populations. The reproductive rate (R0) was significantly lower in the F1 (♀R × ♂S) (28.19) and F1′ (♀S × ♂R) (34.06) progenies compared with their parents, but not with the relaxed BZR-Rns (39.39). The mean generation time (T), intrinsic rate of population growth (rm), and doubling time (DT) differed between REC-S and progenies, with fitness of 0.52 and 0.64 for F1 and F1′, respectively. Overall, the results suggest that the resistance of P. xylostella to lufenuron is stable and that low fitness costs appear to be associated with resistance to lufenuron, although heterozygotes showed lower fitness than their parents. Strategies such as preserving refuge areas, rotation of modes of action, etc., are essential for resistance management and prolonging the efficacy of control agents; this highlights the importance of integrated insecticide resistance management.

Mixed-mode oscillations and chaos in a complex chemical reaction network involving heterogeneous catalysis.

The nonlinear dynamical behavior in a complex isothermal reaction network involving heterogeneous catalysis is studied. The method first determines the multiple steady states in the reaction network. This is followed by an analysis of bifurcation continuations to identify several kinds of bifurcations, including limit point, Bogdanov-Takens, generalized Hopf, period doubling, and generalized period doubling. Numerical simulations are performed around the period doubling and generalized period doubling bifurcations. Rich nonlinear behaviors are observed, including simple sustained oscillations, mixed-mode oscillations, non-mixed-mode chaotic oscillations, and mixed-mode chaotic oscillations. Concentration-time plots, 2D phase portraits, Poincaré maps, maximum Lyapunov exponents, frequency spectra, and cascade of bifurcations are reported. Period-doubling and period-adding routes leading to chaos are observed. Maximum Lyapunov exponents are positive for all the chaotic cases, but they are also positive for some non-chaotic orbits. This result diminishes the reliability of using maximum Lyapunov exponents as a tool for determining chaos in the network under study.

The Correlation Between the Natural Course, Pathologic Properties With Ki-67 Expression in Lung Adenocarcinoma Presenting as Ground-Glass Nodules.

With the increasing use of lung cancer screening, the detection of ground glass nodules (GGNs) has risen. However, the natural course of GGNs and their relationship to pathologic features remains unclear. Differentiating between invasive and pre-invasive lesions based on GGN growth may improve clinical intervention timing. Ki-67, a proliferation marker, holds value in assessing tumor malignancy. This study analyzes the association between GGN growth, pathology, and Ki-67 expression to provide new insights into early-stage lung cancer management. We retrospectively evaluated 183 GGNs with at least two preoperative CT scans. Nodule location, type, natural course, and volume doubling time (VDT) were compared between invasive adenocarcinoma (IAC) and pre-IAC groups. We also assessed differences in Ki-67 expression and correlated VDT with Ki-67 levels. A total of 183 nodules were finally included; gender, nodule location, smoking history, and duration of follow-up did not differ between the IAC group and the pre-IAC group, whereas age was statistically different between the two groups. Of the 183 nodules, 52 showed growth and the predominant pathologic type was IAC, these IACs showed more PSN in nodule type, while the IAC group showed more significant differences in nodule type, nodules growth, and VDT than the pre-IAC group. There were also differences in pathologic type and VDT between different Ki-67 expression groups, and Ki-67 expression gradually increased as VDT decreased. Lung adenocarcinoma (LUAD) presenting as GGNs exhibit distinct natural courses among pathologic subtypes. VDT effectively distinguishes these growth characteristics, with IACs showing shorter VDT. The significant correlation between VDT and Ki-67 expression suggests that combining these parameters may provide valuable insights into the biological behavior and invasiveness of LUAD.

Preoperative Tumor Growth Rate Does Not Predict Overall or Progression-free Survival in Patients With Glioblastoma.

Presurgical tumor volume progression in glioblastoma (GBM) may be a predictor of survival. This study aims to evaluate the potential impact of preoperative tumor growth and other clinical as well as laboratory parameters on overall survival (OS) of GBM patients. We retrospectively analyzed 98 adult patients with GBM who received two magnetic resonance imaging (MRI) scans between 2013 and 2023, before primary surgery and concurrent Stupp chemoradiotherapy. Tumor growth rates were calculated to classify GBM into slower and faster growing categories. Statistical analyses, including Kaplan-Meier and multivariable Cox regression survival analyses, were performed to evaluate the impact of various clinical and treatment-related factors on OS and progression-free survival (PFS). Slower growing tumors had a significantly longer doubling time than faster growing lesions. Univariable analysis showed no significant differences in OS (p=0.12) or PFS (p=0.4) when analyzed according to tumor growth. When stratified by O6-methylguanin-DNA-methyltransferase (MGMT) status, there were still no differences in OS (p=0.14), but in PFS (p=0.009). In the multivariable Cox regression analysis, radiation dose (p=0.02) and the number of adjuvant cycles of temozolomide (TMZ) (p=0.002) were significantly associated with OS. MGMT status (p=0.02) and the number of adjuvant TMZ cycles (p<0.001) were significantly associated with prolonged PFS. Specific volume growth rate (SVGR), patient age, baseline tumor volume, Karnofsky performance status, extent of resection, and total radiation dose were not significantly associated with PFS. SVGR was not significantly associated with OS or PFS. In contrast, MGMT status, radiation dose, and number of adjuvant TMZ cycles were identified as predictors of treatment outcomes. These factors can guide physicians when designing personalized treatment concepts for patients with GBM.

Identification of CD141+vasculogenic precursor cells from human bone marrow and their endothelial engagement in the arteriogenesis by co-transplantation with mesenchymal stem cells

BackgroundCritical limb ischemia (CLI) is a condition characterized by insufficient blood flow to the lower limbs, resulting in severe ischemia and potentially leading to amputation. This study aims to identify novel vasculogenic precursor cells (VPCs) in human bone marrow and evaluate their efficacy in combination with bone marrow-derived mesenchymal stem cells (BM-MSCs) for the treatment of CLI.MethodsEx vivo cultured VPCs and BM-MSCs from bone marrow were characterized and their effects on neovascularization and long-term tissue regeneration were tested in a mouse CLI model.ResultsVPCs, expressing high levels of hepatocyte growth factor and c-MET, were identified from human bone marrow aspirates. These cells exhibited strong vasculogenic capacity in vitro but possessed a cellular phenotype distinct from those of previously reported endothelial precursor cells in circulation or cord blood. They also expressed most surface markers of BM-MSCs and demonstrated multipotent differentiation ability. Screening of 376 surface markers revealed that VPCs uniquely display CD141 (thrombomodulin). CD141+VPCs are present in BM aspirates as a rare population and can be expanded ex vivo with a population doubling time of approximately 20 h, generating an elaborate vascular network even under angiogenic factor-deficient conditions and recruiting BM-MSCs to the network as pericyte-like cells. Intramuscular transplantation of a combination of human CD141+VPCs and BM-MSCs at a ratio of 2:1 resulted in limb salvage, blood flow recovery, and regeneration of large vessels in the femoral artery-removed CLI model, with an efficacy superior to that of singular transplantation. Importantly, large arteries and arterioles in dual cell transplantation expressed human CD31 in the intima and human α-smooth muscle actin in media layer at 4 and 12 weeks, likely indicating their lineage commitment to endothelial cells and vascular smooth muscle, respectively, in vivo.ConclusionDual-cell therapy using BM-derived CD141+ VPCs and BM-MSCs holds potential for further development in clinical trials to treat peripheral artery disease and diabetic ulcers.

Side effects of insecticides used for management of Tuta absoluta Meyrick (Lepidoptera: Gelechidae) on the biocontrol agent Trichogramma brassicae Bezdenko (Hymenoptera: Trichogrammatidae)

Trichogramma brassicae is one of the most important egg parasitoids of many pests including South American tomato pinworm, Tuta absoluta (Lepidoptera: Gelechiidae). In agrosystems, the function of parasitoids can be affected by the application of insecticides. To use biological control agents and pesticides simultaneously in pest management, it is necessary to know the potential effect of pesticides on biological control agents. In this study, the lethal and sublethal effects of four insecticides (flubendiamide, emamectin benzoate + lufenuron, thiocyclam, and spinosad) frequently used to control T. absoluta, were investigated on its parasitoid Trichogramma Brassicae Bezdenko (Hymenoptera: Trichogrammatidae), under controlled laboratory conditions. The results showed that spinosad with an LC50 value of 0.73 mg a.i./ L was highly toxic against adults of T. brassicae in comparison to flubendiamide (4.09 mg a.i./ L), emamectin benzoate + lufenuron (4.17 mg a.i./ L), and thiocyclam (9.59 mg a.i./ L). Furthermore, key demographic parameters such as net reproductive rate (R0), intrinsic rate of increase (rm), mean generation time (T), and doubling time (DT) were significantly decreased after exposure of T. brassicae to the LC30s of spinosad, thiocyclam, flubendiamide, and emamectin benzoate + lufenuron compared to the control. In the light of our results, the four insecticides should be used cautiously in T. absoluta integrated management programs. While the thiocyclam can be combined with the T. brassicae, the flubendiamide and emamectin benzoate + lufenuron are not recommended in the presence of this parasitoid. The use of spinosad should be avoided concomitantly with the release of T. brassicae.

Cross-chiral exponential amplification of an RNA enzyme.

An RNA ligase ribozyme that catalyzes the joining of RNA molecules of the opposite chiral handedness was optimized for the ability to synthesize its own enantiomer from two component fragments. The mirror-image D- and L-ligases operate in concert to provide a system for cross-chiral replication, whereby they catalyze each other's synthesis and undergo mutual amplification at constant temperature, with apparent exponential growth and a doubling time of about 1 h. Neither the D- nor the L-RNA components alone can achieve autocatalytic self-replication. Cross-chiral exponential amplification can be continued indefinitely through a serial-transfer process that provides an ongoing supply of the component D- and L-substrates. Unlike the familiar paradigm of semiconservative nucleic acid replication that relies on Watson-Crick pairing between complementary strands, cross-chiral replication relies on tertiary interactions between structured nucleic acids "across the mirror." There are few examples, outside of biology, of autocatalytic self-replication systems that undergo exponential amplification and there are no prior examples, in either biological or chemical systems, of cross-chiral replication enabling exponential amplification.

Enhanced Performance of Fluidic Phononic Crystal Sensors Using Different Quasi-Periodic Crystals

In this paper, we introduce a comprehensive theoretical study to obtain an optimal highly sensitive fluidic sensor based on the one-dimensional phononic crystal (PnC). The mainstay of this study strongly depends on the high impedance mismatching due to the irregularity of the considered quasi-periodic structure, which in turn can provide better performance compared to the periodic PnC designs. In this regard, we performed the detection and monitoring of the different concentrations of lead nitrate (Pb(NO3)2) and identified it as being a dangerous aqueous solution. Here, a defect layer was introduced through the designed structure to be filled with the Pb(NO3)2 solution. Therefore, a resonant mode was formed within the transmittance spectrum of the considered structure, which in turn shifted due to the changes in the concentration of the detected analyte. The numerical findings demonstrate the role of the different sequences such as Fibonacci, Octonacci, Thue–Morse, and double period on the performance of the designed PhC detector. Meanwhile, the findings of this study show that the double-period quasi-periodic sequence provides the best performance with a sensitivity of 502.6 Hz/ppm, a damping rate of , a maximum quality factor of 8463.5, and a detection limit of 2.45.

Integrated Imaging Probe and Bispecific Antibody Development Enables In Vivo Targeting of Glypican-3–Expressing Hepatocellular Carcinoma

Abstract Glypican-3 (GPC3) is a proteoglycan with high sensitivity and specificity for hepatocellular carcinoma (HCC). We describe the integrated development and validation of a GPC3-targeting optical imaging probe and T cell–redirecting antibody (TRAB) as a theranostic strategy for the detection and treatment of HCC. A novel TRAB targeting GPC3 on HCC tumor cells and the CD3 T-cell receptor as well as a distinct GPC3-specific optical imaging probe were developed from a short peptide. The efficacy of GPC3/CD3 TRAB was evaluated in vitro using IFNγ release and calcein-AM assays. Patient-derived xenografts were used to assess the in vivo efficacy of GPC3/CD3 TRAB and the GPC3 imaging probe for the detection of GPC3+ HCC. GPC3/CD3 TRAB caused a dose-dependent escalation in IFNγ release from inactive peripheral blood T cells (P = 0.001) and higher tumor-cell lysis (P = 0.01) compared with controls in vitro. Intratumorally injected GPC3/CD3 TRAB resulted in significant prolongation of tumor doubling time in the GPC3+ tumors, with an associated reduction of tumor fluorescent signal from the HiLyte 488–conjugated GPC3-specific peptide on optical imaging. These data demonstrate that HCC cell targeting using a GPC3/CD3 TRAB derived from a small peptide enabled effective T-cell activation and induction of a cytotoxic response toward GPC3+ HCC tumor cells both in vitro and in vivo. GPC3-specific optical imaging enabled the detection of the GPC3+ HCC cells and noninvasive monitoring of tumor response to adoptive immunotherapy. The integrated development of a targeted therapeutic and molecular imaging probe provides a promising paradigm for the development of cancer theranostics.

Enhancing bevacizumab efficacy in a colorectal tumor mice model using dextran-coated albumin nanoparticles.

Bevacizumab is a monoclonal antibody (mAb) that prevents the growth of new blood vessels and is currently employed in the treatment of colorectal cancer (CRC). However, like other mAb, bevacizumab shows a limited penetration in the tumors, hampering their effectiveness and inducing adverse reactions. The aim of this work was to design and evaluate albumin-based nanoparticles, coated with dextran, as carriers for bevacizumab in order to promote its accumulation in the tumor and, thus, improve its antiangiogenic activity. These nanoparticles (B-NP-DEX50) displayed a mean size of about 250nm and a payload of about 110µg/mg. In a CRC mice model, these nanoparticles significantly reduced tumor growth and increased tumor doubling time, tumor necrosis and apoptosis more effectively than free bevacizumab. At the end of study, bevacizumab plasma levels were higher in the free drug group, while tumor levels were higher in the B-NP-DEX50 group (2.5-time higher). In line with this, the biodistribution study revealed that nanoparticles accumulated in the tumor core, potentially improving therapeutic efficacy while reducing systemic exposure. In summary, B-NP-DEX can be an adequate alternative to improve the therapeutic efficiency of biologically active molecules, offering a more specific biodistribution to the site of action.

Nodal radiotherapy for prostate adenocarcinoma recurrence: predictive factors for efficacy

BackgroundNodes are the second site for prostate cancer recurrence. Whole-pelvic radiotherapy (WPRT) has shown superiority over nodal stereotactic body radiotherapy (SBRT) in two retrospective cohorts. We aimed to compare both modalities and assess factors associated with treatment outcomes.Materials and methodsThis retrospective multicentric cohort study included patients from five institutions spanning from 2010 to 2022. Patients had a history of prostatic adenocarcinoma classified as N0 M0 at diagnosis with a first nodal-only pelvic castration-sensitive recurrence. Failure-free survival (FFS) was defined as the time from the end of RT to the first failure event–biochemical or imaging recurrence, or death.ResultsA total of 147 patients (pts) were analyzed, mainly treated for a recurrence after initial prostatectomy (87%), with 64 (43.5%) undergoing SBRT and 83 (56.5%) undergoing WPRT. SBRT was chosen mainly for dosimetric constraints (67%) and was associated with a lower rate of concomitant androgen deprivation therapy (ADT) prescription. With a median follow-up of 68 months [inter-quartile range (IQR) = 51], FFS was significantly lower in the SBRT group (p &amp;lt; 0.0001). In multivariable analysis, WPRT and ADT were associated with a longer FFS. Factors associated with a longer FFS after SBRT included associated ADT, lower prostate-specific antigen (PSA) levels, a PSA doubling time &amp;gt;6 months, and a Gleason score &amp;lt;8. SBRT was associated with a lower rate of genitourinary and gastrointestinal grade ≥2 complications.DiscussionFor an isolated pelvic nodal prostate cancer recurrence, SBRT is associated with a shorter FFS compared to WPRT. SBRT is often more convenient for patients and leaves further pelvic salvage options available, so it can be explored as an option for well-informed patients.

Biological and population parameters of Telenomus remus and Trichogramma atopovirilia as biological control agents for Spodopterafrugiperda

Maize production faces a significant threat from Spodoptera frugiperda (J. E. Smith) worldwide; historically, Trichogramma pretiosum Riley has served as the primary augmentative egg parasitoid for its biological control. However, since 2004, Telenomus remus Nixon has emerged as a viable global alternative. On a regional scale, in Mexico, Trichogramma atopovirilia (Oatman & Platner) was theorized to outperform T. pretiosum, proving superior in both laboratory and field conditions in 2020. To further the field efficacy of the augmentative use of parasitoids as biological agents of S. frugiperda, we conducted comparisons of biological and population parameters under laboratory-controlled conditions to determine whether T. remus would be more effective than T. atopovirilia, the best Trichogramma parasitoid in Mexico for S. frugiperda. We found that the former parasitoid had statistically significant longer female and male longevity, as well as a higher proportion of female offspring, and greater numerical values in net reproduction rate, intrinsic rate of increase, and finite rate of increase, but no differences were found in the number of days required for both parasitoids to develop from egg to female or egg to male, as well as in the mean generation time and doubling time. Under the conditions of these trials, T. remus had a 47.02% greater intrinsic rate of increase (rm) and may thus be a more effective biological control agent for S. frugiperda than T. atopovirilia. However, these biological and population parameter comparisons are the first execution worldwide; further studies are needed to validate these promising T. remus results.

Virulome and phylogenomic profiling of a novel Burkholderia pseudomallei strain from an Indian clinical isolate.

Highly pathogenic Burkholderia pseudomallei is the causative agent of melioidosis, a neglected tropical disease endemic in Southeast Asian tropical region. This bacterium encompasses diverse virulence factors which further undergo dynamic gene-expression flux as it transits through distinct environmental niches within the host which may lead to manifestation of differential clinical symptoms. B. pseudomallei, is classified as a Tier 1 select agent in the United States and regarded as a risk group 3 organism in India with the potential to be used as bioweapon. Considering these facts, it is vital to uncover both physiological and genetic heterogeneity of B. pseudomallei, particularly to identify any novel virulence factors that may contribute to pathogenicity. B. pseudomallei strain CM000113 was isolated from a clinical case in India, characterized it for its physiological, biochemical, and prominently genetic traits through WGS. It has a type 2 morphotype with faster doubling time and high biofilm producing capacity as compared to Pseudomonas aeruginosa. The genome size is 7.3 Mbp and it is phylogenetically close to B. pseudomallei strain Mahidol 1106a and Burkholderia mallei Turkey 2. We observed genetic heterogeneity, as key virulence factors that were identified shows sequence dissimilarity with reference strains. Additionally, presence of genomic islands, harbouring two virulence factors, GmhA and GmhB2, associated with pathogenesis indicates possibility of horizontal gene transfer. These results emphasize the need for an extensive study focusing the genome of B. pseudomallei and its associated heterogeneity, to identify molecular biomarkers aiding to develop point-of-care diagnostic kits for early diagnosis of melioidosis.

Chemical Profiling and Pharmaceutical and Biological Activities of Methanolic Extract of Citrullus colocynthis L. Seeds Collected from the Arid Zone of Qassim, Saudi Arabia against Aphis craccivora

Background: Citrullus colocynthis L. (C. colocynthis) is a medicinal plant with a long history of traditional usage in Saudi Arabia, particularly for the treatment of digestive issues such as indigestion and stomach pain.Methods: C. colocynthis seeds were examined using qualitative and quantitative phytochemical methods. Antioxidant testing was conducted using DPPH assay and the reducing power test. Antibacterial properties were evaluated using the well-diffusion test, minimum inhibitory concentration (MIC) test, and minimum bactericidal concentration (MBC) test. The effectiveness of the extract against Aphis craccivora (A. craccivora) was assessed using a leaf-dip bioassay, measuring generation time (GT), net reproduction rate (R0), intrinsic rate of increase (rm), doubling time (DT), and finite rate of growth (λ).Results: The methanolic extract of C. colocynthis seeds included diverse bioactive compounds, a good quantity of phenolic content (60.45 mg GAE/g) and flavonoid content (46.66 mg/g). The antibacterial tests showed that the extract was effective only against Staphylococcus aureus and Proteus mirabilis. The extract recorded inhibition zones of 14.5 ± 0.7 mm and 10.5 ± 0.5 mm for Staphylococcus aureus and Proteus mirabilis, respectively. Staphylococcus aureus showed the greatest sensitivity, with MIC of 6.25 mg/mL and MBC of 25.0 mg/mL. The extract was found to have a fatal concentration (LC50) of 9.02% and a lethal concentration (LC95) of 20.50% against A. craccivora aphid.Conclusions: The current vitro study on C. colocynthis reported that the seeds are effective as antioxidants, antibacterial agents (only against Gram-positive bacteria), and aphicidal agents against aphids. More investigations are recommended to examine the possible toxicity and biochemical interactions in vivo.Keywords: Plants; Biological activity; In vitro study; Citrullus colocynthis; Aphis craccivora; Aphicidal

Transduction of Human Fetal Liver Hematopoietic CD34+ Stem and Progenitor Cells into a Cell Line by Enhancing Telomerase Activity

Background: Human fetal liver hematopoietic stem cells have proven potential as therapeutics but lack extensive research due to their limited supply. Even in vitro expanded fetal liver hematopoietic stem cells enter senescence or lose their self-renewal capacity after a few days in culture. The present study aimed to obtain a homogeneous and persistent supply of hematopoietic stem cells from the fetal liver by establishing a cell line through immortalization of cells by enhancing telomerase activity. Materials and Methods: Human fetal liver hematopoietic CD34+ stem and progenitor cells were transformed and immortalized using retroviruses carrying the human telomerase (hTERT) gene. Following transduction, telomerase activity was assessed using the TRAP assay and telomere length was examined by Southern blotting in transduced cells. Their characterization was conducted using flowcytometry to analyze the CD34+ population of hematopoietic stem cells and their colony forming potential using colony forming unit (CFU) assay. Results: After transduction with hTERT, the life span of human fetal liver hematopoietic CD34+ stem and progenitor cells were extended to 80 population doublings, without any change in cell morphology or population doubling times. Constitutive hTERT expression enhanced the replicative capacity and prevented terminal differentiation of CD34+ fetal liver hematopoietic stem and progenitor cells (FLHSPCs). Moreover, hTERT-transduced stem cells maintained their telomere length and telomerase activity. Conclusion: By introducing telomerase activity into hematopoietic stem and progenitor cells, their lifespan can be extended while maintaining stemness. These modified cells hold promise for in vitro research focused on studying hematopoietic stem cells derived from fetal liver.

Chicken Embryo Fibroblast Viability and Trans-Differentiation Potential for Cultured Meat Production Across Passages.

This study was conducted to analyze the viability of primary chicken embryo fibroblasts and the efficiency of adipogenic trans-differentiation for cultured meat production. In isolating chicken embryo fibroblasts (CEFs) from a heterogeneous cell pool containing chicken satellite cells (CSCs), over 90% of CEFs expressed CD29 and vimentin. The analysis of the proliferative capabilities of CEFs revealed no significant differences in EdU-positive cells (%), cumulative cell number, doubling time, and growth rate from passage 1 to passage 9 (p > 0.05). This indicates that CEFs can be isolated by 2 h of pre-plating and survive stably up to passage 9, and that primary fibroblasts can serve as a valuable cell source for the cultured meat industry. Adipogenic trans-differentiation was induced up to passage 9 of CEFs. As passages increased, lipid accumulation and adipocyte size significantly decreased (p < 0.05). The reduced differentiation rate of primary CEFs with increasing passages poses a major challenge to the cost and efficiency of cultured meat production. Thus, effective cell management and the maintenance of cellular characteristics for a long time are crucial for ensuring stable and efficient cultured fat production in the cultured meat industry.

Optimal timing for initiating androgen receptor signaling inhibitor therapy in patients with nonmetastatic castration-resistant prostate cancer: a multicenter collaborative study.

We determined the optimal timing for initiating androgen receptor signaling inhibitor (ARSI) therapy in patients with nonmetastatic castration-resistant prostate cancer (nmCRPC) and assessed its impact on oncological outcomes. This retrospective study included 145 nmCRPC patients who received enzalutamide, apalutamide or darolutamide at the Jikei University Hospital or its affiliated institutions between May 2014 and November 2022. Patients were stratified based on prostate-specific antigen (PSA) doubling time (PSADT) at CRPC diagnosis and PSA levels at ARSI initiation. Oncological outcomes, including progression-free survival (PFS), metastasis-free survival (MFS), cancer-specific survival and overall survival, were assessed using the Kaplan-Meier curve and Cox regression analysis. The median age of the patients was 73 (interquartile range [IQR]: 52-88) years, and the median follow-up duration was 36 (IQR: 2-104) months. The median PSA level at ARSI initiation was 5.4 (IQR: 2.2-48) ng/ml, and 44.8% of patients had a PSADT <3months. Multivariate analysis revealed that PSADT and PSA levels at ARSI initiation were independent MFS predictors. Patients with a PSADT ≤3months and a PSA level≥5.4ng/ml experienced significantly reduced PFS and MFS. Notably, ARSI initiation at a PSA level ≥5.4ng/ml was associated with worse outcomes, suggesting the potential benefit of earlier intervention. Patients with rapid PSADT are at increased risk of early disease progression, suggesting that immediate treatment may be warranted. In addition, initiating therapy at a PSA level <5.4ng/ml may be associated with improved patient outcomes in patients with low PSADT.

Maternal and neonatal factors’ effects on wharton's jelly mesenchymal stem cell yield

As Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) are easily accessible, easy to isolate, and ethically acceptable, they represent a promising source of MSCs for use in regenerative medicine. Considering decisions on WJ-MSCs collection requires extensive knowledge of the factors that impact their yield. This study's aim was to evaluate the influence of parameters related to mothers and newborns on the WJ-MSCs yield. The WJ-MSCs were isolated and expanded after being isolated from 79 umbilical cord (UC) samples. Population doubling time and cell proliferation were assessed. By flow cytometry analysis, WJ-MSCs were identified by positivity of CD105, CD90, and CD73 and negativity of CD45 and CD34. There was a statistically significant negative correlation between UC width and P1 doubling time. Maternal age and WJ-MSC yield were shown to be negatively correlated. Birth weight and gestational age showed a significant positive correlation between WJ-MSCs yield and neonatal variables. No significant correlations were detected between the WJ-MSCs and the mother parity, nor the neonatal sex, fetal presentation, or head circumference. The WJ-MSCs yield increases with younger maternal age, higher gestational age, and increased neonatal birth weight. Hence, consideration should be given to these factors when selecting the ideal donors.